FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Lattanzi, V Walters, A Drouin, BJ Pearson, JC AF Lattanzi, Valerio Walters, Adam Drouin, Brian J. Pearson, John C. TI Submillimeter spectrum of formic acid SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE catalogs; ISM : molecules; methods : laboratory; molecular data; solar system : formation ID EXCITED VIBRATIONAL-STATES; CIS-HCOOH; ROTATIONAL SPECTRUM; MOLECULAR-STRUCTURE; MICROWAVE-SPECTRUM; GROUND-STATE; CHEMISTRY; DCOOH; SPECTROSCOPY; PROTOSTARS AB We have measured new submillimeter-wave data around 600 GHz and around 1.1 THz for the C-13 isotopologue of formic acid and for the two deuterium isotopomers; in each case for both the trans and cis rotamer. For cis-DCOOH and cis-HCOOD in particular only data up to 50 GHz was previously available. For all species the quality and quantity of molecular parameters has been increased, providing new measured frequencies and more precise and reliable frequencies in the range of existing and near-future submillimeter and far-infrared astronomical spectroscopy instruments such as Herschel, SOFIA, and ALMA. C1 [Lattanzi, Valerio] Univ Roma La Sapienza, Dept Phys, Rome, Italy. [Lattanzi, Valerio; Walters, Adam] Univ Toulouse 3, CNRS, Ctr Etud Spatiale Rayonnements, F-31028 Toulouse 4, France. [Drouin, Brian J.; Pearson, John C.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Lattanzi, V (reprint author), Univ Roma La Sapienza, Dept Phys, Ple Aldo Moro 2, Rome, Italy. EM valerio.lattanzi@cesr.fr NR 41 TC 11 Z9 11 U1 3 U2 8 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD JUN PY 2008 VL 176 IS 2 BP 536 EP 542 DI 10.1086/529521 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 326PU UT WOS:000257672200013 ER PT J AU Rickards, CA Cohen, KD Bergeron, LL Burton, L Khatri, PJ Lee, CT Ryan, KL Cooke, WH Doerr, DF Lurie, KG Convertino, VA AF Rickards, Caroline A. Cohen, Kenneth D. Bergeron, Lindsey L. Burton, Lubrina Khatri, Prateek J. Lee, Christopher T. Ryan, Kathy L. Cooke, William H. Doerr, Don F. Lurie, Keith G. Convertino, Victor A. TI Inspiratory resistance, cerebral blood flow velocity, and symptoms of acute hypotension SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article DE impedance threshold device; hemodynamic oscillations; cerebral blood flow regulation; squat-stand test; hypotension ID INTRATHORACIC PRESSURE REGULATION; HEART-RATE-VARIABILITY; ORTHOSTATIC HYPOTENSION; HEMODYNAMIC-RESPONSES; CENTRAL HYPOVOLEMIA; CARDIAC-ARREST; IMPEDANCE; HUMANS; AUTOREGULATION; STRESS AB Introduction: Symptoms of orthostatic intolerance, e.g., following prolonged bed rest and microgravity exposure, are associated with reductions in cerebral blood flow. We tested the hypothesis that spontaneously breathing through an impedance threshold device (ITD) would attenuate the fall in cerebral blood flow velocity (CBFV) during a hypotensive orthostatic challenge and reduce the severity of reported symptoms. Methods: While breathing through either an active ITD (-7 cm H(2)O inspiratory impedance) or a sham ITD (no impedance), 19 subjects performed a squat stand test (SST). Symptoms upon stand were recorded on a 5-point scale (1 = normal; 5 = faint) of subject-perceived rating (SPR). To address our hypothesis, only data from symptomatic subjects (SPR > 1 during the sham trial) were analyzed (N = 9). Mean arterial blood pressure (MAP) and mean CBFV were measured continuously throughout the SST and analyzed in time and frequency domains. Results: Breathing with the active ITD during the SST reduced the severity of orthostatic symptoms in eight of the nine symptomatic subjects (sham ITD SPR 1.9 +/- 0.1; active ITD SPR, 1.1 +/- 0.1), but there was no statistically distinguishable difference in the reduction of mean CBFV between the two trials (sham ITD, -39 +/- 3% vs. active ITD, -44 +/- 3%). High frequency oscillations in mean CBFV, however, were greater during the active ITD trial (7.8 +/- 2.6 cm . s(-2)) compared with the sham ITD trial (2.5 +/- 0.9 cm . s(-2)). Conclusions: Higher oscillations in CBFV while breathing with the active ITD may account for the reduction in symptom severity during orthostatic hypotension despite the same fall in absolute CBFV. C1 [Rickards, Caroline A.; Ryan, Kathy L.; Convertino, Victor A.] USA, Inst Surg Res, Ft Sam Houston, TX 78234 USA. [Cohen, Kenneth D.] Bionet Corp, Kennedy Space Ctr, Kennedy Space Ctr, FL USA. [Bergeron, Lindsey L.; Burton, Lubrina; Khatri, Prateek J.; Lee, Christopher T.] NASA, Space Flight & Life Sci Training Program, Kennedy Space Ctr, Kennedy Space Ctr, FL USA. [Cooke, William H.] Univ Texas San Antonio, Dept Hlth & Kinesiol, San Antonio, TX USA. [Lurie, Keith G.] Adv Circulatory Syst Inc, Minneapolis, MN USA. [Lurie, Keith G.] Univ Minnesota, Dept Emergency Med, Minneapolis, MN 55455 USA. [Lurie, Keith G.] Hennepin Cty Med Ctr, Minneapolis Med Res Fdn, Minneapolis, MN 55415 USA. RP Rickards, CA (reprint author), USA, Inst Surg Res, 3400 Rawley E Chambers Ave, Ft Sam Houston, TX 78234 USA. EM caroline.rickards@us.army.mil NR 34 TC 11 Z9 11 U1 0 U2 5 PU AEROSPACE MEDICAL ASSOC PI ALEXANDRIA PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 USA SN 0095-6562 J9 AVIAT SPACE ENVIR MD JI Aviat. Space Environ. Med. PD JUN PY 2008 VL 79 IS 6 BP 557 EP 564 DI 10.3357/ASEM.2149.2008 PG 8 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 306TA UT WOS:000256269500001 PM 18581938 ER PT J AU Fishman, J Bowman, KW Burrows, JP Richter, A Chance, KV Edwards, DP Martin, RV Morris, GA Pierce, RB Ziemke, JR Al-Saadi, JA Creilson, JK Schaack, TK Thompson, AM AF Fishman, Jack Bowman, Kevin W. Burrows, John P. Richter, Andreas Chance, Kelly V. Edwards, David P. Martin, Randall V. Morris, Gary A. Pierce, R. Bradley Ziemke, Jerald R. Al-Saadi, Jassim A. Creilson, John K. Schaack, Todd K. Thompson, Anne M. TI Remote sensing of tropospheric pollution from space SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID CARBON-MONOXIDE; SATELLITE MEASUREMENTS; ATMOSPHERIC CO; TROPICAL ATLANTIC; GOME MEASUREMENTS; NITROGEN-DIOXIDE; AIR-POLLUTION; OZONE BUDGET; EMISSIONS; NO2 AB Geostationary satellite observations of chemically reactive trace gases will provide unique insight into the evolution and extent of air pollution with the temporal resolution necessary to address air quality on a daily basis. C1 [Fishman, Jack; Al-Saadi, Jassim A.; Creilson, John K.] NASA, Langley Res Ctr, Hampton, VA 23681 USA. [Bowman, Kevin W.] CALTECH, Jet Prop Lab, Pasadena, CA USA. [Burrows, John P.; Richter, Andreas] Univ Bremen, Bremen, Germany. [Chance, Kelly V.] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. [Edwards, David P.] Natl Ctr Atmospher Res, Boulder, CO 80307 USA. [Martin, Randall V.] Dalhousie Univ, Halifax, NS, Canada. [Martin, Randall V.] Harvard Univ, Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. [Morris, Gary A.] Valparaiso Univ, Valparaiso, IN 46383 USA. [Pierce, R. Bradley] NOAA, NESDIS, STAR, Madison, WI USA. [Ziemke, Jerald R.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Schaack, Todd K.] Univ Wisconsin, Madison, WI USA. [Thompson, Anne M.] Penn State Univ, University Pk, PA 16802 USA. RP Fishman, J (reprint author), NASA, Langley Res Ctr, Mail Stop 401A, Hampton, VA 23681 USA. EM jack.fishman@nasa.gov RI Richter, Andreas/C-4971-2008; Pierce, Robert Bradley/F-5609-2010; Martin, Randall/C-1205-2014; Burrows, John/B-6199-2014; Thompson, Anne /C-3649-2014; OI Richter, Andreas/0000-0003-3339-212X; Pierce, Robert Bradley/0000-0002-2767-1643; Martin, Randall/0000-0003-2632-8402; Burrows, John/0000-0002-6821-5580; Thompson, Anne /0000-0002-7829-0920; Chance, Kelly/0000-0002-7339-7577 NR 85 TC 54 Z9 58 U1 2 U2 27 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0003-0007 EI 1520-0477 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD JUN PY 2008 VL 89 IS 6 BP 805 EP 821 DI 10.1175/2008BAMS2526.1 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 323RZ UT WOS:000257467400014 ER PT J AU Rind, D AF Rind, D. TI The consequences of not knowing low-and high-latitude climate sensitivity SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID DOUBLED CO2 CLIMATE; LAST GLACIAL MAXIMUM; SEA-ICE; POLAR AMPLIFICATION; TEMPERATURE-GRADIENTS; STRATOSPHERIC OZONE; MODEL SENSITIVITY; MIDDLE ATMOSPHERE; RADIATION BUDGET; STORM TRACKS AB We still can't predict future climate responses at low and high latitudes, which constrains our ability to forecast changes in atmospheric dynamics and regional climate. C1 NASA, Goddard Space Flight Ctr, Inst Space Studies, New York, NY 10025 USA. RP Rind, D (reprint author), NASA, Goddard Space Flight Ctr, Inst Space Studies, New York, NY 10025 USA. EM drind@giss.nasa.gov NR 68 TC 14 Z9 14 U1 0 U2 6 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0003-0007 EI 1520-0477 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD JUN PY 2008 VL 89 IS 6 BP 855 EP 864 DI 10.1175/2007BAMS2520.1 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 323RZ UT WOS:000257467400018 ER PT J AU Marshall, ST Cooke, ML Owen, SE AF Marshall, Scott T. Cooke, Michele L. Owen, Susan E. TI Effects of nonplanar fault topology and mechanical interaction on fault-slip distributions in the Ventura basin, California SO BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA LA English DT Article ID SAN-CAYETANO FAULT; LOS-ANGELES BASIN; 1994 NORTHRIDGE EARTHQUAKES; WESTERN TRANSVERSE RANGES; OAK-RIDGE FAULT; SOUTHERN-CALIFORNIA; STRAIN ACCUMULATION; SEISMIC-REFLECTION; ACTIVE FAULTS; THRUST SYSTEM AB To assess the control of fault geometry and mechanical interactions on fault-slip distributions in a complex natural system, we present results from three-dimensional mechanical models incorporating both nonplanar and rectangular planar representations of active faults within the Ventura basin region of southern California. We find that the incorporation of geologically constrained nonplanar fault surfaces into numerical models of active deformation results in a better match to available geologic slip-rate data than models utilizing rectangular planar fault surfaces. The model results demonstrate that nonplanar fault geometry and mechanical interactions exert a strong control on resultant slip distributions. Additionally, we find that slip rates at most locations along the surface trace of Ventura faults are not likely to represent average values for the entire fault surface. We propose that results from three-dimensional mechanical models using realistic (i.e., nonplanar) fault geometry can be used to both predict slip rates at specific locations and determine whether existing site-specific slip-rate estimates are representative of average fault-slip rates. Although geometric irregularities along-fault surfaces should resist slip, planar faults can have lesser slip than nonplanar faults due to the differing mechanical interactions among nearby faults in the two representations. This suggests that models using simplified or planar fault geometry are likely to inaccurately simulate regional deformation. We assert that detailed knowledge of three-dimensional fault shape as well as the geometry and configuration of deep fault intersections is essential for accurate seismic hazard characterization of regions of complex faulting such as the Ventura basin of southern California. C1 [Marshall, Scott T.; Cooke, Michele L.] Univ Massachusetts, Dept Geosci, Amherst, MA 01003 USA. [Owen, Susan E.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Marshall, ST (reprint author), Univ Massachusetts, Dept Geosci, 611 N Pleasant St, Amherst, MA 01003 USA. NR 75 TC 26 Z9 26 U1 0 U2 9 PU SEISMOLOGICAL SOC AMER PI ALBANY PA 400 EVELYN AVE, SUITE 201, ALBANY, CA 94706-1375 USA SN 0037-1106 EI 1943-3573 J9 B SEISMOL SOC AM JI Bull. Seismol. Soc. Amer. PD JUN 1 PY 2008 VL 98 IS 3 BP 1113 EP 1127 DI 10.1785/0120070159 PG 15 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 307GH UT WOS:000256306900004 ER PT J AU Stoner, AW Ryer, CH Parker, SJ Auster, PJ Wakefield, WW AF Stoner, Allan W. Ryer, Clifford H. Parker, Steven J. Auster, Peter J. Wakefield, W. Waldo TI Evaluating the role of fish behavior in surveys conducted with underwater vehicles SO CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES LA English DT Article ID DEEP-WATER FISH; COD GADUS-MORHUA; HABITAT ASSOCIATIONS; SEBASTOLOBUS SPP.; ROCKFISH SEBASTES; ARTIFICIAL-LIGHT; BRITISH-COLUMBIA; TRAWLING VESSEL; REEF FISHES; PISCES-IV AB It is often assumed that visual survey data provide more accurate fish counts than conventional extractive gear. As a result, use of underwater vehicles to assess the abundance and distribution of fishes has increased rapidly over recent years. However, a review of observations reported for 48 demersal marine fish taxa showed that almost all respond in some way to underwater vehicles. Whether or not movements or changes in behavior affect survey bias is more difficult to assess. A simple conceptual model is presented to evaluate relationships between stimulus intensity, distances from the vehicle where reactions occur, and survey bias. Largest bias is caused by attraction or avoidance that occurs outside the field of cameras or observers. While light level and vehicle speed have been explored experimentally in a few cases, much remains to be learned about how bias varies among species, age groups, different vehicles, and operating conditions. Given poor understanding of survey bias, we recommend that surveys be conducted with minimum possible variation in operations and that vehicle time is devoted to experimental evaluation of methods. There is no good substitute for direct observations on fish behavior, distribution, and abundance; and survey design can be improved through experimentation. C1 [Stoner, Allan W.; Ryer, Clifford H.] NOAA, Alaska Fisheries Sci Ctr, Natl Marine Fisheries Serv, Fisheries Behav Ecol Program, Newport, OR 97365 USA. [Parker, Steven J.] Oregon Dept Fish & Wildlife, Newport, OR 97365 USA. [Auster, Peter J.] Univ Connecticut, Natl Undersea Res Ctr, Groton, CT 06340 USA. [Auster, Peter J.] Univ Connecticut, Dept Marine Sci, Groton, CT 06340 USA. [Wakefield, W. Waldo] NOAA, Natl Marine Fisheries Serv, NW Fisheries Sci Ctr, Newport, OR 97365 USA. RP Stoner, AW (reprint author), NOAA, Alaska Fisheries Sci Ctr, Natl Marine Fisheries Serv, Fisheries Behav Ecol Program, 2030 SE Marine Sci Dr, Newport, OR 97365 USA. EM al.stoner@noaa.gov NR 66 TC 67 Z9 68 U1 0 U2 21 PU NATL RESEARCH COUNCIL CANADA-N R C RESEARCH PRESS PI OTTAWA PA BUILDING M 55, OTTAWA, ON K1A 0R6, CANADA SN 0706-652X J9 CAN J FISH AQUAT SCI JI Can. J. Fish. Aquat. Sci. PD JUN PY 2008 VL 65 IS 6 BP 1230 EP 1243 DI 10.1139/F08-032 PG 14 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA 322ER UT WOS:000257358500019 ER PT J AU Ghose, S Watson, KA Working, DC Connell, JW Smith, JG Sun, YP AF Ghose, S. Watson, K. A. Working, D. C. Connell, J. W. Smith, J. G., Jr. Sun, Y. P. TI Thermal conductivity of ethylene vinyl acetate copolymer/nanofiller blends SO COMPOSITES SCIENCE AND TECHNOLOGY LA English DT Article DE Elvax (TM); thermal properties; extrusion; nanostructures; polymer-matrix composites ID CARBON-NANOTUBE COMPOSITES; IN-SITU POLYMERIZATION; GRAPHITE NANOCOMPOSITES; MATRIX COMPOSITES; HEAT-FLOW; FABRICATION; POLYETHYLENE; ENHANCEMENT; SUSPENSIONS; TRANSPORT AB To reduce weight and increase mobility, comfort, and performance of future spacesuits, flexible, thermally conductive fabrics and plastic tubes are needed for the Liquid Cooling and Ventilation Garment. As an approach to raise thermal conductivity (TC) of an ethylene vinyl acetate copolymer (Elvax (TM) 260), it was compounded with carbon based nanofillers: multi-walled carbon nanotubes (MWCNTs), vapor grown carbon nanofibers (CNFs), and expanded graphite (EG) as well as metallized CNFs, nickel nanostrands, boron nitride, and powdered aluminum. Ribbons and tubing of the nanocomposites, in which the nanofillers were aligned in the direction of flow, were extruded. Compression molding was used to fabricate nanocomposites in which the nanofillers were randomly oriented. TC of the samples was measured in the direction of, and perpendicular to, the alignment direction and significant improvement in TC (up to 24-fold) was observed when measurements were made in the direction of alignment. Published by Elsevier Ltd. C1 [Ghose, S.; Watson, K. A.] Natl Inst Aerosp, Hampton, VA 23666 USA. [Working, D. C.; Connell, J. W.; Smith, J. G., Jr.] NASA, Langley Res Ctr, Hampton, VA 23681 USA. [Sun, Y. P.] Clemson Univ, Dept Chem, Clemson, SC 29634 USA. RP Ghose, S (reprint author), Natl Inst Aerosp, Hampton, VA 23666 USA. EM Sayata.Ghose-1@nasa.gov NR 43 TC 59 Z9 60 U1 3 U2 53 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0266-3538 J9 COMPOS SCI TECHNOL JI Compos. Sci. Technol. PD JUN PY 2008 VL 68 IS 7-8 BP 1843 EP 1853 DI 10.1016/j.compscitech.2008.01.016 PG 11 WC Materials Science, Composites SC Materials Science GA 304US UT WOS:000256135200033 ER PT J AU Zypman, FR Ferrante, J AF Zypman, Fredy R. Ferrante, John TI Analytical algorithm for Equivalent Crystal Theory SO COMPUTATIONAL MATERIALS SCIENCE LA English DT Article DE equivalent crystal theory; Lambert function; computational speed optimization; semi-empirical methods ID METALS; ENERGY; ENERGETICS; SURFACES AB Equivalent crystal theory (ECT) is a semi-empirical technique used for the calculation of defect energetics in metals and semiconductors. The implementation of the method involves the solution of transcendental equations. Although this is not a problem for simple defects, for complex defects, Monte Carlo and molecular dynamics calculations in large systems, it could be the speed-determining limitation in a calculation. In this paper we propose a procedure for bypassing this step and obtaining the desired result directly. The form of the particular transcendental equations suggest a different approach, namely, the equation can be cast in the form of the Lambert function that can be readily evaluated from standard routines. We test this scheme by evaluating the surface energies for a variety of metallic elements and by standard numerical approaches, and demonstrate that they agree to within a few ppm. (C) 2007 Elsevier B.V. All rights reserved. C1 [Zypman, Fredy R.] Yeshiva Univ, Dept Phys, New York, NY 10033 USA. [Ferrante, John] NASA Glenn, Cleveland, OH 44135 USA. RP Zypman, FR (reprint author), Yeshiva Univ, Dept Phys, New York, NY 10033 USA. EM zypman@yu.edu NR 14 TC 3 Z9 3 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0927-0256 J9 COMP MATER SCI JI Comput. Mater. Sci. PD JUN PY 2008 VL 42 IS 4 BP 659 EP 663 DI 10.1016/j.commatsci.2007.09.017 PG 5 WC Materials Science, Multidisciplinary SC Materials Science GA 313ZA UT WOS:000256777300017 ER PT J AU Kiris, CC Kwak, D Chan, W Housman, JA AF Kiris, Cetin C. Kwak, Dochan Chan, William Housman, Jeffrey A. TI High-fidelity simulations of unsteady flow through turbopumps and flowliners SO COMPUTERS & FLUIDS LA English DT Article AB High-fidelity computations were carried out to analyze the orbiter liquid hydrogen (LH2) feedline flowliner and the low-pressure-fuel-turbopump (LPFTP). Computations were performed on the Columbia platform which is a 10,240-processor supercluster consisting of 20 Altix nodes with 512 processors each. Various computational models were used to characterize the unsteady flow features in the turbopump, including the orbiter LPFTP inducer, the orbiter manifold and an experimental test article used to represent the manifold. Unsteady flow originating from the orbiter LPFTP inducer is one of the major contributors to the high-frequency cyclic loading that results in high cycle fatigue damage to the gimbal flowliners just upstream of the LPFTP. The flowfields for the orbiter manifold and representative test article are computed and analyzed for similarities and differences. An incompressible Navier-Stokes flow solver INS3D, based on the artificial compressibility method, was used to compute the flow of liquid hydrogen in each test article. Published by Elsevier Ltd. C1 [Kiris, Cetin C.; Kwak, Dochan; Chan, William] NASA, Ames Res Ctr, NAS Div, Moffett Field, CA 94035 USA. [Housman, Jeffrey A.] UC Davis, Grad Grp Appl Math, Davis, CA USA. RP Kiris, CC (reprint author), NASA, Ames Res Ctr, NAS Div, Moffett Field, CA 94035 USA. EM ckiris@mail.arc.nasa.gov NR 8 TC 11 Z9 15 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0045-7930 J9 COMPUT FLUIDS JI Comput. Fluids PD JUN PY 2008 VL 37 IS 5 BP 536 EP 546 DI 10.1016/j.compfluid.2007.07.010 PG 11 WC Computer Science, Interdisciplinary Applications; Mechanics SC Computer Science; Mechanics GA 293GF UT WOS:000255322700007 ER PT J AU Yee, HC Sjogreen, B AF Yee, H. C. Sjoegreen, B. TI Adaptive filtering and limiting in compact high order methods for multiscale gas dynamics and MHD systems SO COMPUTERS & FLUIDS LA English DT Article ID HYPERBOLIC CONSERVATION-LAWS; FINITE-DIFFERENCE SCHEME; NAVIER-STOKES EQUATIONS; WAVELET TRANSFORMS; EULER EQUATIONS; FLOWS; MAGNETOHYDRODYNAMICS; INSTABILITY; INTERFACE AB The adaptive multistep linear and nonlinear filters for multiscale shock/turbulence gas dynamics and magnetohydrodynamics (MHD) flows of the authors are extended to include compact high order central differencing as the spatial base scheme. The adaptive mechanism makes used of multiresolution wavelet decomposition of the computed flow data as sensors for numerical dissipative control. The objective is to expand the work initiated in [Yee HC, Sjogreen B. Nonlinear filtering in compact high order schemes. In: Proceedings of the 19th ICNSP and 7th APPTC conference; 2005; J Plasma Phys 2006;72:833-36] and compare the performance of adaptive multistep filtering in compact high order schemes with adaptive filtering in standard central (non-compact) schemes for multiscale problems containing shock waves. Published by Elsevier Ltd. C1 [Yee, H. C.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. [Sjoegreen, B.] KTH, NADA, Stockholm, Sweden. RP Yee, HC (reprint author), NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. EM yee@nas.nasa.gov; bjorns@nada.kth.se NR 49 TC 12 Z9 13 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0045-7930 J9 COMPUT FLUIDS JI Comput. Fluids PD JUN PY 2008 VL 37 IS 5 BP 593 EP 619 DI 10.1016/j.compfluid.2007.07.015 PG 27 WC Computer Science, Interdisciplinary Applications; Mechanics SC Computer Science; Mechanics GA 293GF UT WOS:000255322700011 ER PT J AU Moser, DE Cooke, WJ AF Moser, Danielle E. Cooke, William J. TI Updates to the MSFC meteoroid stream model SO EARTH MOON AND PLANETS LA English DT Article; Proceedings Paper CT Meteoroids Conference 2007 CY JUN 11-15, 2007 CL CosmoCaixa Sci Museum, Barcelona, SPAIN SP Inst Space Sci, Inst Estudies Espacials Catalunya HO CosmoCaixa Sci Museum DE aurigids; comet ejection; draconids; leonids; meteor shower; meteoroids; model predictions; numerical integration; perseids; stream model ID COMET P/SWIFT-TUTTLE; P/GIACOBINI-ZINNER; GIACOBINI-ZINNER; DUST; NUCLEUS; SHOWER; JAPAN AB The Marshall Space Flight Center (MSFC) Meteoroid Stream Model simulates particle ejection and subsequent evolution from comets in order to provide meteor shower forecasts to spacecraft operators for hazard mitigation and planning purposes. The model, previously detailed in Moser and Cooke (Earth Moon Planets 95, 141 (2004)), has recently been updated; the changes include the implementation of the RADAU integrator, an improved planetary treatment, and the inclusion of general relativistic effects in the force function. The results of these updates are investigated with respect to various meteoroid streams and the outcome presented. C1 [Moser, Danielle E.; Cooke, William J.] NASA, UNITeS Stanley Associates, Meteoroid Environm Off, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Moser, DE (reprint author), NASA, UNITeS Stanley Associates, Meteoroid Environm Off, George C Marshall Space Flight Ctr, Bldg 4487-EV13, Huntsville, AL 35812 USA. EM danielle.e.moser@nasa.gov NR 26 TC 2 Z9 2 U1 0 U2 2 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0167-9295 EI 1573-0794 J9 EARTH MOON PLANETS JI Earth Moon Planets PD JUN PY 2008 VL 102 IS 1-4 BP 285 EP 291 DI 10.1007/s11038-007-9159-1 PG 7 WC Astronomy & Astrophysics; Geosciences, Multidisciplinary SC Astronomy & Astrophysics; Geology GA 278BQ UT WOS:000254258900040 ER PT J AU Suggs, RM Cooke, WJ Suggs, RJ Swift, WR Hollon, N AF Suggs, Robert M. Cooke, William J. Suggs, Ronnie J. Swift, Wesley R. Hollon, Nicholas TI The NASA lunar impact monitoring program SO EARTH MOON AND PLANETS LA English DT Article; Proceedings Paper CT Meteoroids Conference 2007 CY JUN 11-15, 2007 CL CosmoCaixa Sci Museum, Barcelona, SPAIN SP Inst Space Sci, Inst Estudies Espacials Catalunya HO CosmoCaixa Sci Museum DE meteoroids; lunar impacts; space environments; hypervelocity impact testing AB NASA's Meteoroid Environment Office has implemented a program to monitor the Moon for meteoroid impacts from the Marshall Space Flight Center. Using off-the-shelf telescopes and video equipment, the Moon is monitored for as many as 10 nights per month, depending on weather. Custom software automatically detects flashes which are confirmed by a second telescope, photometrically calibrated using background stars, and published on a website for correlation with other observations. Hypervelocity impact tests at the Ames Vertical Gun Range facility have begun to determine the luminous efficiency and ejecta characteristics. The purpose of this research is to define the impact ejecta environment for use by lunar spacecraft designers of the Constellation manned lunar program. The observational techniques and preliminary results will be discussed. C1 [Suggs, Robert M.] NASA, George C Marshall Space Flight Ctr, Space Environm Team, EV13, Huntsville, AL 35812 USA. [Cooke, William J.; Suggs, Ronnie J.] NASA, George C Marshall Space Flight Ctr, Meteoroid Environm Off, EV13, Huntsville, AL 35812 USA. [Swift, Wesley R.] NASA, George C Marshall Space Flight Ctr, Raytheon MSFC Grp, Space Environm Team,EV13, Huntsville, AL 35812 USA. [Hollon, Nicholas] NASA, George C Marshall Space Flight Ctr, Jacobs Technol MSFC Grp, Space Environm Team,EV13, Huntsville, AL 35812 USA. [Hollon, Nicholas] Villanova Univ, Villanova, PA 19085 USA. RP Suggs, RM (reprint author), NASA, George C Marshall Space Flight Ctr, Space Environm Team, EV13, Huntsville, AL 35812 USA. EM rob.suggs@nasa.gov NR 10 TC 17 Z9 18 U1 0 U2 4 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0167-9295 EI 1573-0794 J9 EARTH MOON PLANETS JI Earth Moon Planets PD JUN PY 2008 VL 102 IS 1-4 BP 293 EP 298 DI 10.1007/s11038-007-9184-0 PG 6 WC Astronomy & Astrophysics; Geosciences, Multidisciplinary SC Astronomy & Astrophysics; Geology GA 278BQ UT WOS:000254258900041 ER PT J AU Swift, W Suggs, R Cooke, B AF Swift, Wesley Suggs, Robert Cooke, Bill TI Algorithms for lunar flash video search, measurement, and archiving SO EARTH MOON AND PLANETS LA English DT Article; Proceedings Paper CT Meteoroids Conference 2007 CY JUN 11-15, 2007 CL CosmoCaixa Sci Museum, Barcelona, SPAIN SP Inst Space Sci, Inst Estudies Espacials Catalunya HO CosmoCaixa Sci Museum DE moon; lunar flash; TLP; transient lunar phenomenon; video analysis; flash measurement ID HYPERVELOCITY IMPACTS; LUMINOUS EFFICIENCY; MOON AB Lunar meteoroid impact flashes provide a method to estimate the flux of the large meteoroid flux and thus their hazard to spacecraft. Although meteoroid impacts on the Moon have been detected using video methods for over a decade, the difficulty of manually searching hours of video for the rare, extremely brief impact flashes has discouraged the technique's systematic implementation. A prototype has been developed for the purpose of automatically searching lunar video records for impact flashes, eliminating false detections, editing the returned possible flashes, and archiving and documenting the results. Several utilities for measurement, analysis, and location of the flashes on the moon included in the program are demonstrated. Application of the program to a year's worth of lunar observations is discussed along with examples of impact flashes. C1 [Swift, Wesley] NASA, George C Marshall Space Flight Ctr, MSFC ED44, Raytheon, Huntsville, AL 35812 USA. [Suggs, Robert; Cooke, Bill] NASA, George C Marshall Space Flight Ctr, EV13, Huntsville, AL 35812 USA. RP Swift, W (reprint author), NASA, George C Marshall Space Flight Ctr, MSFC ED44, Raytheon, Bldg 4487 C-151, Huntsville, AL 35812 USA. EM Wesley.r.swift@nasa.gov NR 18 TC 2 Z9 2 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0167-9295 EI 1573-0794 J9 EARTH MOON PLANETS JI Earth Moon Planets PD JUN PY 2008 VL 102 IS 1-4 BP 299 EP 303 DI 10.1007/s11038-007-9226-7 PG 5 WC Astronomy & Astrophysics; Geosciences, Multidisciplinary SC Astronomy & Astrophysics; Geology GA 278BQ UT WOS:000254258900042 ER PT J AU Nuth, JA AF Nuth, Joseph A., III TI What was the volatile composition of the planetesimals that formed the Earth? SO EARTH MOON AND PLANETS LA English DT Article; Proceedings Paper CT Meteoroids Conference 2007 CY JUN 11-15, 2007 CL CosmoCaixa Sci Museum, Barcelona, SPAIN SP Inst Space Sci, Inst Estudies Espacials Catalunya HO CosmoCaixa Sci Museum DE accretion; Earth; planetesimals; water; organics; oceans; volatiles ID LATE HEAVY BOMBARDMENT; TERRESTRIAL PLANETS; SOLAR NEBULA; PRIMITIVE CHONDRITES; ORIGIN; METEORITE; SYSTEM; WATER; MOON; ABUNDANCES AB Is there an asteroid type or meteorite class that best exemplifies the materials that went into the Earth? Carbonaceous chondrites were once the objects of choice, and in the minds of many this choice is still valid. However, the origin of primitive chondritic meteorites is unclear. At the extremes they could either be fragments of very small parent bodies that never became hot enough to undergo geochemical modification other than mild lithification, or remnants of the uppermost layers of a body that had undergone a significant degree of internal differentiation, while the top layers remained cool due to radiative heat loss or loss of volatiles to space. This latter case is problematic if one considers these objects as precursors to the Earth since the timescale for the evolution of such a small body could be longer than the timescale for the accretion of the Earth. Large-scale circulation of materials in the primitive solar nebula could greatly increase the diversity of materials near 1 AU while also making the entire inner solar system both more homogeneous and much wetter than previously expected. The total mass of the nebula is an important, but poorly constrained factor controlling the growth of planetesimals. There is also a selection effect that dominates our sampling of the planetesimals that may have existed 4.5 billion years ago; namely, small fragile bodies are more likely to be lost from the system or ground down by collisions between small bodies, yet these are precisely those that may have dominated the population from which the Earth accreted. The composition of these aggregates could have played a very important role in the early chemical evolution of the Earth. In particular, the Earth may have been much wetter and richer in hydrocarbons and other reducing materials than previously suspected. C1 NASA, Goddard Space Flight Ctr, Astrochem Lab, Greenbelt, MD 20771 USA. RP Nuth, JA (reprint author), NASA, Goddard Space Flight Ctr, Astrochem Lab, Code 691, Greenbelt, MD 20771 USA. EM Joseph.A.Nuth@nasa.gov RI Nuth, Joseph/E-7085-2012 NR 55 TC 5 Z9 5 U1 0 U2 5 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0167-9295 J9 EARTH MOON PLANETS JI Earth Moon Planets PD JUN PY 2008 VL 102 IS 1-4 BP 435 EP 445 DI 10.1007/s11038-007-9208-9 PG 11 WC Astronomy & Astrophysics; Geosciences, Multidisciplinary SC Astronomy & Astrophysics; Geology GA 278BQ UT WOS:000254258900060 ER PT J AU Nuth, JA Lowrance, JL Carruthers, GR AF Nuth, Joseph A., III Lowrance, John L. Carruthers, George R. TI NEOCAM: The Near Earth Object Chemical Analysis Mission SO EARTH MOON AND PLANETS LA English DT Article; Proceedings Paper CT Meteoroids Conference 2007 CY JUN 11-15, 2007 CL CosmoCaixa Sci Museum, Barcelona, SPAIN SP Inst Space Sci, Inst Estudies Espacials Catalunya HO CosmoCaixa Sci Museum DE meteor; spectra; ultraviolet; meteor shower; space observations ID COSMIC SPHERULES; PRIMITIVE EARTH; METEOR SPECTRA; LEONID METEOR; 860 NM; ORBITS AB The prime measurement objective of the Near Earth Object Chemical Analysis Mission (NEOCAM) is to obtain the ultraviolet spectra of meteors entering the terrestrial atmosphere from similar to 125 to 300 nm in meteor showers. All of the spectra will be collected using a slitless ultraviolet spectrometer in Earth orbit. Analysis of these spectra will reveal the degree of chemical diversity in the meteors, as observed in a single meteor shower. Such meteors are traceable to a specific parent body and we know exactly when the meteoroids in a particular shower were released from that parent body (Asher, in: Arlt (ed.) Proc. International Meteor Conference, 2000; Lyytinen and van Flandern, Earth Moon Planets 82-83:149-166, 2000). By observing multiple apparitions of meteor showers we can therefore obtain quasi-stratigraphic information on an individual comet or asteroid. We might also be able to measure systematic effects of chemical weathering in meteoroids from specific parent bodies by looking for correlations in the depletions of the more volatile elements as a function of space exposure (Borovicka et al., Icarus 174:15-30, 2005). By observing the relation between meteor entry characteristics (such as the rate of deceleration or breakup) and chemistry we can determine if our meteorite collection is deficient in the most volatile-rich samples. Finally, we can obtain a direct measurement of metal deposition into the terrestrial stratosphere that may act to catalyze atmospheric chemical reactions. C1 [Nuth, Joseph A., III] NASA, Goddard Space Flight Ctr, Astrochem Lab, Greenbelt, MD 20771 USA. [Lowrance, John L.] Princeton Sci Instruments Inc, Monmouth Jct, NJ 08852 USA. [Carruthers, George R.] USN, Res Lab, Div Space Sci, Ultraviolet Measurements Sect, Washington, DC 20375 USA. RP Nuth, JA (reprint author), NASA, Goddard Space Flight Ctr, Astrochem Lab, Code 691, Greenbelt, MD 20771 USA. EM Joseph.A.Nuth@NASA.gov RI Nuth, Joseph/E-7085-2012 NR 38 TC 0 Z9 0 U1 1 U2 5 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0167-9295 J9 EARTH MOON PLANETS JI Earth Moon Planets PD JUN PY 2008 VL 102 IS 1-4 BP 495 EP 504 DI 10.1007/s11038-007-9178-y PG 10 WC Astronomy & Astrophysics; Geosciences, Multidisciplinary SC Astronomy & Astrophysics; Geology GA 278BQ UT WOS:000254258900065 ER PT J AU Edwards, DL Cooke, W Moser, DE Swift, W AF Edwards, David L. Cooke, William Moser, Danielle E. Swift, Wesley TI Measurement of ejecta from normal incident hypervelocity impact on lunar regolith simulant SO EARTH MOON AND PLANETS LA English DT Article; Proceedings Paper CT Meteoroids Conference 2007 CY JUN 11-15, 2007 CL CosmoCaixa Sci Museum, Barcelona, SPAIN SP Inst Space Sci, Inst Estudies Espacials Catalunya HO CosmoCaixa Sci Museum DE lunar; meteoroid impact; ejecta distribution; impact testing AB The National Aeronautics and Space Administration (NASA) continues to make progress toward long-term lunar habitation. Critical to the design of a lunar habitat is an understanding of the lunar surface environment. A subject for further definition is the lunar impact ejecta environment. The document NASA SP-8013 was developed for the Apollo program and is the latest definition of the ejecta environment. There is concern that NASA SP-8013 may over-estimate the lunar ejecta environment. NASA's Meteoroid Environment Office (MEO) has initiated several tasks to improve the accuracy of our understanding of the lunar surface ejecta environment. This paper reports the results of experiments on projectile impact into powered pumice targets, simulating unconsolidated lunar regolith. The Ames Vertical Gun Range (AVGR) was used to accelerate spherical Pyrex projectiles of 0.29g to velocities ranging between 2.5 and 5.18 km/s. Impact on the pumice target occurred at normal incidence. The ejected particles were detected by thin aluminum foil targets placed around the pumice target in a 0.5 Torr vacuum. A simplistic technique to characterize the ejected particles was formulated. Improvements to this technique will be discussed for implementation in future tests. C1 [Edwards, David L.; Cooke, William] NASA, George C Marshall Space Flight Ctr, Natl Environm Branch, Huntsville, AL 35812 USA. [Moser, Danielle E.] Morgan A Stanley Co, MSFC, Huntsville, AL 35812 USA. [Swift, Wesley] Raytheon Co, MSFC, Huntsville, AL 35812 USA. RP Edwards, DL (reprint author), NASA, George C Marshall Space Flight Ctr, Natl Environm Branch, EV13 MSFC, Huntsville, AL 35812 USA. EM David.L.Edwards@nasa.gov; William.Cooke@nasa.gov; Danielle.E.Moser@nasa.gov; Wesley.Swift@nasa.gov NR 3 TC 2 Z9 2 U1 0 U2 2 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0167-9295 J9 EARTH MOON PLANETS JI Earth Moon Planets PD JUN PY 2008 VL 102 IS 1-4 BP 549 EP 553 DI 10.1007/s11038-007-9198-7 PG 5 WC Astronomy & Astrophysics; Geosciences, Multidisciplinary SC Astronomy & Astrophysics; Geology GA 278BQ UT WOS:000254258900071 ER PT J AU Agogino, A Tumer, K AF Agogino, A. Tumer, K. TI Efficient evaluation functions for evolving coordination SO EVOLUTIONARY COMPUTATION LA English DT Article DE evolution strategies; distributed control; fitness evaluation ID BEHAVIORS AB This paper presents fitness evaluation functions that efficiently evolve coordination in large multi-component systems. In particular, we focus on evolving distributed control policies that are applicable to dynamic and stochastic environments. While it is appealing to evolve such policies directly for an entire system, the search space is prohibitively large in most cases to allow such an approach to provide satisfactory results. Instead, we present an approach based on evolving system components individually where each component aims to maximize its own fitness function. Though this approach sidesteps the exploding state space concern, it introduces two new issues: (1) how to create component evaluation functions that are aligned with the global evaluation function; and (2) how to create component evaluation functions that are sensitive to the fitness changes of that component, while remaining relatively insensitive to the fitness changes of other components in the system. If the first issue is not addressed, the resulting system becomes uncoordinated; if the second issue is not addressed, the evolutionary process becomes either slow to converge or worse, incapable of converging to good solutions. This paper shows how to construct evaluation functions that promote coordination by satisfying these two properties. We apply these evaluation functions to the distributed control problem of coordinating multiple rovers to maximize aggregate information collected. We focus on environments that are highly dynamic (changing points of interest), noisy (sensor and actuator faults), and communication limited (both for observation of other rovers and points of interest) forcing the rovers to evolve generalized solutions. On this difficult coordination problem, the control policy evolved using aligned and component-sensitive evaluation functions outperforms global evaluation functions by up to 400%. More notably, the performance improvements increase when the problems become more difficult (larger, noisier, less communication). In addition we provide an analysis of the results by quantifying the two characteristics (alignment and sensitivity discussed above) leading to a systematic study of the presented fitness functions. C1 [Agogino, A.] NASA, UCSC, Ames Res Ctr, Moffett Field, CA 94035 USA. [Tumer, K.] Oregon State Univ, Corvallis, OR 97331 USA. RP Agogino, A (reprint author), NASA, UCSC, Ames Res Ctr, Mailstop 269-3, Moffett Field, CA 94035 USA. EM Adrian.K.Agogino@nasa.gov; kagan.tumer@oregonstate.edu NR 38 TC 32 Z9 32 U1 1 U2 2 PU MIT PRESS PI CAMBRIDGE PA ONE ROGERS ST, CAMBRIDGE, MA 02142-1209 USA SN 1063-6560 EI 1530-9304 J9 EVOL COMPUT JI Evol. Comput. PD SUM PY 2008 VL 16 IS 2 BP 257 EP 288 DI 10.1162/evco.2008.16.2.257 PG 32 WC Computer Science, Artificial Intelligence; Computer Science, Theory & Methods SC Computer Science GA 316NV UT WOS:000256957800004 PM 18554102 ER PT J AU Giannakopoulou, D Pasareanu, CS AF Giannakopoulou, Dimitra Pasareanu, Corina S. TI Special issue on learning techniques for compositional reasoning SO FORMAL METHODS IN SYSTEM DESIGN LA English DT Editorial Material ID VERIFICATION; ASSUMPTIONS C1 [Giannakopoulou, Dimitra; Pasareanu, Corina S.] NASA, Ames Res Ctr, Mountain View, CA 94035 USA. RP Pasareanu, CS (reprint author), NASA, Ames Res Ctr, Mountain View, CA 94035 USA. EM Dimitra.Giannakopoulou@nasa.gov; Corina.S.Pasareanu@nasa.gov NR 5 TC 4 Z9 5 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0925-9856 J9 FORM METHOD SYST DES JI Form. Methods Syst. Des. PD JUN PY 2008 VL 32 IS 3 BP 173 EP 174 DI 10.1007/s10703-008-0054-9 PG 2 WC Computer Science, Theory & Methods SC Computer Science GA 304DG UT WOS:000256089600001 ER PT J AU Pasareanu, CS Giannakopoulou, D Bobaru, MG Cobleigh, JM Barringer, H AF Pasareanu, Corina S. Giannakopoulou, Dimitra Bobaru, Mihaela Gheorghiu Cobleigh, Jamieson M. Barringer, Howard TI Learning to divide and conquer: applying the L* algorithm to automate assume-guarantee reasoning SO FORMAL METHODS IN SYSTEM DESIGN LA English DT Article DE assume-guarantee reasoning; model checking; labeled transition systems; learning; proof rules; compositional verification; safety properties ID COMPOSITIONAL VERIFICATION; ASSUMPTIONS; CHECKING AB Assume-guarantee reasoning enables a "divide-and-conquer" approach to the verification of large systems that checks system components separately while using assumptions about each component's environment. Developing appropriate assumptions used to be a difficult and manual process. Over the past five years, we have developed a framework for performing assume-guarantee verification of systems in an incremental and fully automated fashion. The framework uses an off-the-shelf learning algorithm to compute the assumptions. The assumptions are initially approximate and become more precise by means of counterexamples obtained by model checking components separately. The framework supports different assume-guarantee rules, both symmetric and asymmetric. Moreover, we have recently introduced alphabet refinement, which extends the assumption learning process to also infer assumption alphabets. This refinement technique starts with assumption alphabets that are a subset of the minimal interface between a component and its environment, and adds actions to it as necessary until a given property is shown to hold or to be violated in the system. We have applied the learning framework to a number of case studies that show that compositional verification by learning assumptions can be significantly more scalable than non-compositional verification. C1 [Pasareanu, Corina S.; Giannakopoulou, Dimitra] NASA, Ames Res Ctr, RIACS, Moffett Field, CA 94035 USA. [Bobaru, Mihaela Gheorghiu] Univ Toronto, Dept Comp Sci, Toronto, ON M5S 3G4, Canada. [Cobleigh, Jamieson M.] Univ Massachusetts, Dept Comp Sci, Amherst, MA 01003 USA. [Barringer, Howard] Univ Manchester, Sch Comp Sci, Manchester M13 9PL, Lancs, England. RP Pasareanu, CS (reprint author), NASA, Ames Res Ctr, RIACS, N269-230, Moffett Field, CA 94035 USA. EM Corina.S.Pasareanu@nasa.gov; Dimitra.Giannakopoulou@nasa.gov; mg@cs.toronto.edu; jcobleig@cs.umass.edu; howard.barringer@manchester.ac.uk NR 31 TC 35 Z9 36 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0925-9856 EI 1572-8102 J9 FORM METHOD SYST DES JI Form. Methods Syst. Des. PD JUN PY 2008 VL 32 IS 3 BP 175 EP 205 DI 10.1007/s10703-008-0049-6 PG 31 WC Computer Science, Theory & Methods SC Computer Science GA 304DG UT WOS:000256089600002 ER PT J AU Peslier, AH Woodland, AB Wolff, JA AF Peslier, Anne H. Woodland, Alan B. Wolff, John A. TI Fast kimberlite ascent rates estimated from hydrogen diffusion profiles in xenolithic mantle olivines from southern Africa SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID NOMINALLY ANHYDROUS MINERALS; OXYGEN-ISOTOPE COMPOSITION; SPINEL-PERIDOTITES; WATER DIFFUSION; ORTHO-PYROXENE; HIGH-PRESSURE; MAGMA; BENEATH; DISSOLUTION; INCLUSIONS AB Fourier transform infrared spectrometry (FTIR) analyses of olivines from peridotite xenoliths found in southern African kimberlites indicate 0 to 80 ppm H2O concentrations. OH absorbance profiles across olivine grains show homogeneous H contents from core to edge for most samples. In one sample the olivines are H-free, while another has olivines characterized by lower H contents at the grain edges compared to the cores, indicating H loss during transport of the xenolith to the surface. Flat or near-flat H profiles place severe constraints on the duration of H loss from olivine grains, with implications for kimberlite magma ascent rates. Diffusion equations were used to estimate times of H loss of about 4 h for the sample with heterogeneous olivine H contents. Resulting kimberlite ascent rates are calculated to be 5-37 m s(-1) minimum, although these estimates are highly dependent on volatile contents and degassing behavior of the host kimberlite magma. Xenolithic olivines from alkali basalts generally have lower H contents and more pronounced H diffusion profiles than do those from kimberlites. This difference is likely caused by higher magma temperatures and lower ascent rates of alkali basalts compared to kimberlites. (C) 2008 Elsevier Ltd. All rights reserved. C1 [Peslier, Anne H.] Jacobs Technol, ESCG, Houston, TX 77058 USA. [Peslier, Anne H.] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. [Woodland, Alan B.] Goethe Univ Frankfurt, D-6000 Frankfurt, Germany. [Wolff, John A.] Washington State Univ, Sch Earth & Environm Sci, Pullman, WA 99164 USA. RP Peslier, AH (reprint author), Jacobs Technol, ESCG, Mail Code JE23,2224 Bay Area Blvd, Houston, TX 77058 USA. EM anne.h.peslier@nasa.gov; woodland@em.uni-frankfurt.de; jawolff@mail.wsu.edu RI Peslier, Anne/F-3956-2010 NR 71 TC 74 Z9 82 U1 4 U2 23 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0016-7037 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD JUN 1 PY 2008 VL 72 IS 11 BP 2711 EP 2722 DI 10.1016/j.gca.2008.03.019 PG 12 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 309MK UT WOS:000256464400010 ER PT J AU Canuto, VM Dubovikov, MS AF Canuto, V. M. Dubovikov, M. S. TI Reply to the comment by T. J. McDougall, P. R. Gent and S. Drijfhout SO GEOPHYSICAL AND ASTROPHYSICAL FLUID DYNAMICS LA English DT Article DE TRM; diapycnal flux; adiabatic approximation ID MESOSCALE EDDIES; DYNAMICAL MODEL; TRACER EQUATION; OCEAN; PARAMETERIZATION; OGCMS C1 [Canuto, V. M.] NASA, Goddard Inst Space Studies, Greenbelt, MD 20771 USA. [Canuto, V. M.] Columbia Univ, Dept Appl Phys & Math, New York, NY 10027 USA. [Dubovikov, M. S.] Columbia Univ, Ctr Climate Syst Res, New York, NY 10027 USA. RP Canuto, VM (reprint author), NASA, Goddard Inst Space Studies, Greenbelt, MD 20771 USA. EM vcanuto@giss.nasa.gov NR 12 TC 0 Z9 0 U1 0 U2 1 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0309-1929 J9 GEOPHYS ASTRO FLUID JI Geophys. Astrophys. Fluid Dyn. PD JUN PY 2008 VL 102 IS 3 BP 257 EP 264 DI 10.1080/03091920801996433 PG 8 WC Astronomy & Astrophysics; Geochemistry & Geophysics; Mechanics SC Astronomy & Astrophysics; Geochemistry & Geophysics; Mechanics GA 348EX UT WOS:000259194900002 ER PT J AU Occhipinti, G Kherani, EA Lognonne, P AF Occhipinti, Giovanni Kherani, E. Alam Lognonne, Philippe TI Geomagnetic dependence of ionospheric disturbances induced by tsunamigenic internal gravity waves SO GEOPHYSICAL JOURNAL INTERNATIONAL LA English DT Article DE numerical solutions; acoustic-gravity waves; non-linear electromagnetics; ionosphere/atmosphere interactions; tsunamis; early warning ID SUMATRA-ANDAMAN EARTHQUAKE; ELECTRON-CONTENT; REALISTIC ATMOSPHERE; DENALI EARTHQUAKE; SURFACE-WAVES; GPS DETECTION; MODEL; IRREGULARITIES; OSCILLATIONS; PROPAGATION AB A series of ionospheric anomalies following the Sumatra tsunami has been recently reported in the literature. These anomalies show the signature in the ionosphere of tsunami-generated internal gravity waves (IGW) propagating in the neutral atmosphere over the ocean. All these anomalies, observed in the total electron content (TEC) measured by GPS or altimeters, show geographical heterogeneity in the perturbed TEC amplitude and suggest a dependence on geomagnetic latitude. This latitudinal dependence has been taken into account in the previous 3-D modelling used for the interpretation of the TEC Topex and Jason data. Here we present an accurate description of the ocean-atmosphere-ionosphere coupling method, and focus on the properties of the propagation of tsunamigenic IGW in the neutral atmosphere and their interaction with the ionospheric plasma. The analytical dependence on the geomagnetic field in the neutral-plasma coupling discussed in detail and quantitative modelling is used to describe the propagation of a simple tsunami wave at the global scale. What emphasize the role of geomagnetic field within the neutral-plasma coupling at the equatorial and mid-latitude regions. The results, presented here in terms of electron density and TEC variations, show a strong geometric dependance involving the magnetic field inclination and the propagative direction of the tsunami. If the strongest electron density and TEC perturbations are located around -15 degrees and 15 degrees North, the structure and amplitude of the modelled perturbation changes in the two studied cases-south-north and north-south tsunami propagation. C1 [Occhipinti, Giovanni; Kherani, E. Alam; Lognonne, Philippe] Inst Phys Globe Paris, UMR7154, Paris, France. [Occhipinti, Giovanni] NASA, Jet Prop Lab, Washington, DC 20546 USA. RP Occhipinti, G (reprint author), Inst Phys Globe Paris, UMR7154, Paris, France. EM ninto@ipgp.jussieu.fr RI Occhipinti, Giovanni/A-2850-2011; Lognonne, Philippe/F-8846-2010; Kherani, Esfhan/N-9292-2013 OI Occhipinti, Giovanni/0000-0001-9323-3185; NR 58 TC 55 Z9 56 U1 2 U2 9 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0956-540X EI 1365-246X J9 GEOPHYS J INT JI Geophys. J. Int. PD JUN PY 2008 VL 173 IS 3 BP 753 EP 765 DI 10.1111/j.1365-246X.2008.03760.x PG 13 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 298ST UT WOS:000255708100001 ER PT J AU Wong, S AF Wong, Sharon TI Diversity - Making space for everyone at NASA/Goddard space flight center using dialogue to break through barriers SO HUMAN RESOURCE MANAGEMENT LA English DT Article AB Diversity is perhaps one of the most important concepts in today's business environment. Organizations have expended significant resources in this area in an effort to improve the bottom line, to become an employer of choice, to avoid lawsuits, and to "do the right thing." Diversity is also one of the most difficult initiatives to implement in organizations because there are such diverse views on what diversity is and how deeply it should be woven into an organization's culture. Diversity can be difficult also because the dimensions of diversity are closely tied to an individual's personal beliefs, perceptions, and life experiences. These personal beliefs often present barriers to full inclusion and participation in the workforce. At NASA/Goddard, we are using dialogue and other initiatives to break through these barriers to create and sustain an equitable and inclusive workplace. Our Diversity Dialogue Project has been key in helping us to identify and address the diversity issues and concerns at the Center and in helping us to move confidently toward the future. This article describes the diversity journey at NASA/Goddard thus far and provides insight into the challenges and opportunities of such a journey. C1 NASA, Goddard Space Flight Ctr, Off Director, Greenbelt, MD 20771 USA. RP Wong, S (reprint author), NASA, Goddard Space Flight Ctr, Off Director, Code 100, Greenbelt, MD 20771 USA. EM Sharon.M.Wong@nasa.gov NR 2 TC 6 Z9 6 U1 0 U2 3 PU JOHN WILEY & SONS INC PI HOBOKEN PA 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0090-4848 J9 HUM RESOUR MANAGE JI Hum. Resour. Manage. PD SUM PY 2008 VL 47 IS 2 BP 389 EP 399 DI 10.1002/hrm.20218 PG 11 WC Psychology, Applied; Management SC Psychology; Business & Economics GA 305JK UT WOS:000256174200012 ER PT J AU Marti-Cardona, B Steissberg, TE Schladow, SG Hook, SJ AF Marti-Cardona, B. Steissberg, T. E. Schladow, S. G. Hook, S. J. TI Relating fish kills to upwellings and wind patterns in the Salton Sea SO HYDROBIOLOGIA LA English DT Article; Proceedings Paper CT Salton Sea Centennial Symposium/Symposium on Century of Symbiosis among Agriculture, Wildlife and People CY MAR, 2005 CL San Diego, CA DE infrared; remote sensing; MODIS ID SURFACE SHEAR-STRESS; LAKE TAHOE; CALIFORNIA; ASTER; MODIS; USA AB In recent years, the extreme eutrophication of the Salton Sea has been associated with massive fish kills and associated bird kills. Analysis of the magnitude and direction of high wind events indicates that major fish kills are preceded by strong and persistent wind events, with a 24-h accumulated wind magnitude above a critical threshold of approximately 90 m/s. Twelve of the 14 cases of reported fish kills analyzed were found to be preceded by such wind conditions. The winds could potentially produce upwellings of hypolimnetic water at the upwind end of the Sea, resulting in the entire water column being low in dissolved oxygen and high in concentrations of hydrogen sulfide and ammonium. Remotely sensed thermal infrared data from the MODIS instrument on the Terra satellite was available for 5 of the 14 fish kills analyzed. Evaluation of satellite-derived surface temperature maps for these 5 fish kills shows that upwellings did take place after the wind events, affecting a large fraction of the Sea's area. The location of the upwelling and the fish kills coincided in all cases, confirming the relationship among wind patterns, upwellings, and fish kills in the Salton Sea. The importance of physically mediated processes, such as upwellings, need to be considered in evaluating future remediation strategies for the Salton Sea. C1 [Schladow, S. G.] Univ Calif Davis, Tahoe Environm Res Ctr, Davis, CA 95616 USA. [Marti-Cardona, B.; Steissberg, T. E.; Schladow, S. G.] Univ Calif Davis, Dept Civil & Environm Engn, Davis, CA 95616 USA. [Hook, S. J.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Schladow, SG (reprint author), Univ Calif Davis, Tahoe Environm Res Ctr, Davis, CA 95616 USA. EM gschladow@ucdavis.edu NR 23 TC 15 Z9 15 U1 2 U2 13 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0018-8158 J9 HYDROBIOLOGIA JI Hydrobiologia PD JUN PY 2008 VL 604 BP 85 EP 95 DI 10.1007/s10750-008-9315-2 PG 11 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 275RJ UT WOS:000254089000008 ER PT J AU Anderson, RC Dohm, JM Haldermann, AFC Pounders, E Golombek, M Castano, A AF Anderson, R. C. Dohm, J. M. Haldermann, A. F. C. Pounders, E. Golombek, M. Castano, A. TI Centers of tectonic activity in the eastern hemisphere of Mars SO ICARUS LA English DT Article DE tectonics ID THARSIS REGION; ORIENTATION DATA; BASIN; DEFORMATION; HISTORIES; PROVINCE; ORIGIN AB We compiled a paleotectonic map for the eastern hemisphere of Mars to determine if extensional tectonic features (graben) are radial or compressional tectonic features (wrinkle ridges) are concentric to centers of tectonic activity defined by axisymmetric stress fields. Using a vector analysis technique all latitude and longitude points (P bins) are tested to see if they lie on great circle extensions of extensional structures (the plane defined by the maximum and intermediate principal stresses) or great circle perpendiculars to compressional structures (the plane defined by the maximum and minimum compressional stresses). Centers of tectonic activity are defined as 5 degrees areas whose concentrations of great circle extensions of tectonic features are statistically significant (e.g., 3 sigma or 7.4 sigma for large populations) and therefore are not the result of random noise. Our paleotectonic investigation has identified four statistically significant centers of tectonic activity within the eastern hemisphere: Elysium, Hadriaca/Tyrrhena-Hellas, Isidis-Syrtis, and Arabia Terra. Two of these centers (Hadriaca/Tyrrhena and Isidis-Syrtis) meet the 7.4 sigma statistical criteria and thus represent primary centers of tectonic activity with axisymmetric stress fields. The remaining two meet the 3 sigma statistical criteria and thus are defined as secondary centers of tectonic activity. Because the structures that define the centers extend over 80 degrees of the planet the defined centers of tectonic activity are regional in character and related to modified impact basins or volcanic centers (all are more limited in extent than the Tharsis stress system that extends over the entire western hemisphere). The observation that statistically significant centers of tectonic activity are quantifiably and statistically identified argues that the crust and lithosphere of the eastern hemisphere at a regional scale is not dominated by regional inhomogeneities and anisotropies. (C) 2008 Elsevier Inc. All rights reserved. C1 [Anderson, R. C.; Haldermann, A. F. C.; Pounders, E.; Golombek, M.; Castano, A.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Dohm, J. M.] Univ Arizona, Dept Hydrol & Water Resources, Tucson, AZ 85721 USA. [Haldermann, A. F. C.] European Space Agcy, European Space Res & Technol Ctr, HME ME, NL-2200 AG Noordwijk, Netherlands. RP Anderson, RC (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,MS 264-421, Pasadena, CA 91109 USA. EM robert.c.anderson@jpl.nasa.gov RI Dohm, James/A-3831-2014 NR 35 TC 9 Z9 9 U1 0 U2 7 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD JUN PY 2008 VL 195 IS 2 BP 537 EP 546 DI 10.1016/j.icarus.2007.12.027 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 304SD UT WOS:000256128500003 ER PT J AU Kahre, MA Hollingsworth, JL Haberle, RM Murphy, JR AF Kahre, Melinda A. Hollingsworth, Jeffery L. Haberle, Robert M. Murphy, James R. TI Investigations of the variability of dust particle sizes in the martian atmosphere using the NASA Ames General Circulation Model SO ICARUS LA English DT Article DE Mars, atmosphere; atmospheres, structure ID THERMAL EMISSION SPECTROMETER; NUMERICAL SIMULATIONS; MAPPER OBSERVATIONS; MARS PATHFINDER; POLAR-REGIONS; VIKING LANDER; STORMS; CYCLE; INERTIA AB We present a Mars General Circulation Model (GCM) numerical investigation of the physical processes (i.e., wind stress and dust devil dust lifting and atmospheric transport) responsible for temporal and spatial variability of suspended dust particle sizes. Measurements of spatial and temporal variations in airborne dust particles sizes in the martian atmosphere have been derived from Mars Global Surveyor (MGS) Thermal Emission Spectrometer (TES) spectral and emission phase function data [Wolff, M.J., Clancy, R.T., 2003. J. Geophys. Res. (Planets) 108 (E9), doi:10.1029/2003JE002057. 1-1; Clancy, R.T., Wolff, M.J., Christensen, P.R., 2003. J. Geophys. Res. (Planets) 108 (E9), doi:10.1029/2003JE002058. 2-1]. The range of dust particle sizes simulated by the NASA Ames GCM is qualitatively consistent with TES-derived observations of effective dust particle size variability. Model results suggest that the wind stress dust lifting scheme (which produces regionally confined dust lifting) is the process responsible for the majority of the dust particle size variability in the martian atmosphere. Additionally, model results suggest that atmospheric transport processes play an important role in the evolution of atmospheric dust particles sizes during substantial dust storms on Mars. Finally, we show that including the radiative effects of a spatially variable particle size distribution significantly influences thermal and dynamical fields during the dissipation phase of the simulated global dust storm. (C) 2008 Elsevier Inc. All rights reserved. C1 [Kahre, Melinda A.; Hollingsworth, Jeffery L.; Haberle, Robert M.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. [Murphy, James R.] New Mexico State Univ, Dept Astron, Las Cruces, NM 88003 USA. RP Kahre, MA (reprint author), NASA, Ames Res Ctr, MSC 245-3, Moffett Field, CA 94035 USA. EM kahrema@mintz.are.nasa.gov NR 41 TC 32 Z9 32 U1 2 U2 11 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 EI 1090-2643 J9 ICARUS JI Icarus PD JUN PY 2008 VL 195 IS 2 BP 576 EP 597 DI 10.1016/j.icarus.2008.01.023 PG 22 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 304SD UT WOS:000256128500006 ER PT J AU Busch, MW Benner, LAM Ostro, SJ Giorgini, JD Jurgens, RF Rose, R Daniel, JSC Magri, C Margot, JL Nolan, MC Hine, AA AF Busch, Michael W. Benner, Lance A. M. Ostro, Steven J. Giorgini, Jon D. Jurgens, Raymond F. Rose, Randy Scheeres, Daniel J. Magri, Christopher Margot, Jean-Luc Nolan, Michael C. Hine, Alice A. TI Physical properties of near-Earth Asteroid (33342) 1998 WT24 SO ICARUS LA English DT Article DE asteroids, composition; asteroids, dynamics ID EROS; YARKOVSKY; EVOLUTION; YORP AB During its close Earth approach in 2001, the E-class near-Earth Asteroid (33342) 1998 WT24 was the focus of extensive radar, optical, and thermal infrared observations. We present a physical model of this object, estimated from Arecibo and Goldstone radar images that cover multiple rotations and span over 100 degrees of sky motion. The asteroid has an equivalent diameter of 415 +/- 40 m and a diffuse radar scattering law that is identical in both senses of circular polarization, implying a surface that is extremely rough on centimeter-to-decimeter scales. The shape is dominated by three large basins, which may be impact craters or a relic of past dynamical disruption of the object. Analysis of YORP perturbations on WT24's spin state predicts that the asteroid's spin rate is decreasing, at a rate of 2 x 10(-7) deg s(-1) yr(-1). Simply extrapolating this rate suggests that the asteroid will despin over the next 150 kyr and was spinning at its surface disruption rate 75 kyr ago, but the rotational evolution of WT24 depends on the surface's thermal properties and probably is more complex than a simple spin-down. (C) 2008 Elsevier Inc. All rights reserved. C1 [Busch, Michael W.] CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA. [Benner, Lance A. M.; Ostro, Steven J.; Giorgini, Jon D.; Jurgens, Raymond F.; Rose, Randy] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Scheeres, Daniel J.] Univ Michigan, Dept Aerosp Engn, Ann Arbor, MI 48109 USA. [Magri, Christopher] Univ Maine Farmington, Farmington, ME 04938 USA. [Margot, Jean-Luc] Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. [Nolan, Michael C.; Hine, Alice A.] Natl Astron & Ionosphere Ctr, Arecibo Observ, Arecibo, PR 00613 USA. RP Busch, MW (reprint author), CALTECH, Div Geol & Planetary Sci, MC 150-21, Pasadena, CA 91125 USA. EM busch@caltech.edu RI Margot, Jean-Luc/A-6154-2012; Nolan, Michael/H-4980-2012 OI Margot, Jean-Luc/0000-0001-9798-1797; Nolan, Michael/0000-0001-8316-0680 NR 26 TC 12 Z9 13 U1 0 U2 0 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD JUN PY 2008 VL 195 IS 2 BP 614 EP 621 DI 10.1016/j.icarus.2008.01.020 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 304SD UT WOS:000256128500008 ER PT J AU Mitri, G Showman, AP AF Mitri, Giuseppe Showman, Adam P. TI A model for the temperature-dependence of tidal dissipation in convective plumes on icy satellites: Implications for Europa and Enceladus SO ICARUS LA English DT Article DE Enceladus; Europa; geophysics; ices; interiors; Jupiter, satellites; Saturn, satellites ID HEAT-FLUX; SHELL; ORIGIN; OCEAN; STATE; WATER AB To explain the formation of surface features on Europa, Enceladus, and other satellites, many authors have postulated the spatial localization of tidal heating within convective plumes. However, the concept that enhanced tidal heating can occur within a convective plume has not been rigorously tested. Most models of this phenomenon adopt a tidal heating with a temperature-dependence derived for an incompressible, homogeneous (zero-dimensional) Maxwell material, but it is unclear whether this formulation is relevant to the heterogeneous situation of a warm plume surrounded by cold ice. To determine whether concentrated dissipation can occur in convective plumes, we develop a two-dimensional model to compute the volumetric dissipation rate for an idealized, vertically oriented, isolated convective plume obeying a Maxwellian viscoelastic compressible rheology. We apply the model to the Europa and Enceladus ice shells, and we investigate the consequences for partial melting and resurfacing processes on these bodies. We find that the tidal heating is strongly temperature dependent in a convective ice plume and could produce elevated temperatures and local partial melting in the ice shells of Europa and Enceladus. Our calculation provides the first quantitative verification of the hypothesis by Sotin et al. [Sotin, C., Head, J.W., Tobie, G., 2002. Geophys. Res. Lett. 29. 74-1] and others that the tidal dissipation rate is a strong function of temperature inside a convective plume. On Europa, such localized heating could help allow the formation of domes and chaos terrains by convection. On Enceladus, localized tidal heating in a thermal plume could explain the concentrated activity at the south pole and its associated heat transport of 2-7 GW. (C) 2008 Elsevier Inc. All rights reserved. C1 [Mitri, Giuseppe] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Showman, Adam P.] Univ Arizona, Dept Planetary Sci, Tucson, AZ 85721 USA. [Showman, Adam P.] Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. RP Mitri, G (reprint author), CALTECH, Jet Prop Lab, M-S 183-501,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM giuseppe.mitri@jpl.nasa.gov NR 31 TC 24 Z9 24 U1 0 U2 8 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD JUN PY 2008 VL 195 IS 2 BP 758 EP 764 DI 10.1016/j.icarus.2008.01.010 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 304SD UT WOS:000256128500019 ER PT J AU Cooper, NJ Murray, CD Evans, MW Beurle, K Jacobson, RA Porco, CC AF Cooper, N. J. Murray, C. D. Evans, M. W. Beurle, K. Jacobson, R. A. Porco, C. C. TI Astrometry and dynamics of Anthe (S/2007 S 4), a new satellite of Saturn SO ICARUS LA English DT Article DE satellites, dynamics; Saturn, satellites; resonances, orbital ID ADDITIONAL SMALL SATELLITES; EXISTENCE; ORBITS; FIELD AB We describe the astrometry and dynamics of Anthe (S/2007 S 4), a new satellite of Saturn discovered in images obtained using the Imaging Science Subsystem (ISS) of the Cassini spacecraft. Included are details of 63 observations, of which 28 were obtained with Cassini's narrow-angle camera (NAC) and 35 using its wide-angle camera (WAC), covering an observation time-span of approximately 3 years. We estimate the diameter of Anthe to be similar to 1.8 km. Orbit modeling based on a numerical integration of the full equations of motion fitted to the observations show that Anthe is in a first-order 11: 10 mean motion resonance with Mimas. Two resonant arguments are librating: phi(1) = 11 lambda' - 10 lambda - pi and phi(2) = 11 lambda' - 10 lambda - pi' - Omega' + Omega, where lambda, pi and Omega refer to the mean longitude, longitude of pericenter and longitude of ascending node of Mimas and Anthe, with the primed quantities corresponding to Anthe. These resonances cause periodic variations in the orbital elements. The semi-major axis varies by 26 km over a 913-day period. Anthe is also close to a second-order eccentricity-type mean motion resonant relationship of the form 77:75 with Methone. Since Methone is also in a first-order resonance with Mimas [Spitale, J.N., Jacobson, R.A., Porco, C.C., Owen, W.M., 2006. Astron. J. 132, 692-710], an additional indirect perturbation exists between Methone and Anthe via Mimas. Neither effect is detectable in the orbit fitting and the short-term dynamical evolution of Anthe is dominated by the Mimas-Anthe resonances alone. The expected modulation effect from the Mimas-Tethys 4:2 inclination resonance is also insignificant over this time period. By including Cassini ISS observations of Mimas in the numerical integration fit, we estimate the GM of Mimas to be 2.509 +/- 0.004 km(3) s(-2), consistent with Jacobson et at. [Jacobson, R.A., Spitale, J., Porco, C.C., Owen, W.M., 2006. Astron. J. 132, 711-713]. (C) 2008 Elsevier Inc. All rights reserved. C1 [Cooper, N. J.; Murray, C. D.; Evans, M. W.; Beurle, K.] Queen Mary Univ London, Sch Math Sci, Astron Unit, London E1 4NS, England. [Jacobson, R. A.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Porco, C. C.] Space Sci Inst, CICLOPS, Boulder, CO 80301 USA. RP Cooper, NJ (reprint author), Queen Mary Univ London, Sch Math Sci, Astron Unit, Mile End Rd, London E1 4NS, England. EM n.cooper@qmul.ac.uk NR 24 TC 12 Z9 12 U1 0 U2 3 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD JUN PY 2008 VL 195 IS 2 BP 765 EP 777 DI 10.1016/j.icarus.2008.01.006 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 304SD UT WOS:000256128500020 ER PT J AU Nixon, CA Achterberg, RK Vinatier, S Bezard, B Coustenis, A Irwin, PGJ Teanby, NA de Kok, R Romani, PN Jennings, DE Bjoraker, GL Flasar, FM AF Nixon, C. A. Achterberg, R. K. Vinatier, S. Bezard, B. Coustenis, A. Irwin, P. G. J. Teanby, N. A. de Kok, R. Romani, P. N. Jennings, D. E. Bjoraker, G. L. Flasar, F. M. TI The C-12/C-13 isotopic ratio in Titan hydrocarbons from Cassini/CIRS infrared spectra SO ICARUS LA English DT Article DE Titan; abundances, atmospheres; atmospheres, composition; infrared observations; spectroscopy ID HETERODYNE OBSERVATIONS; SPECTROSCOPIC DATABASE; LATITUDINAL VARIATIONS; JUPITERS ATMOSPHERE; MASS-SPECTROMETER; HCN; STRATOSPHERE; CIRS; HC3N; TEMPERATURE AB We have analyzed infrared spectra of Titan recorded by the Cassini Composite Infrared Spectrometer (CIRS) to measure the isotopic ratio C-12/C-13 in each of three chemical species in Titan's stratosphere: CH4, C2H2 and C2H6. This is the first measurement of C-12/C-13 in any C-2 molecule on Titan, and the first measurement of (CH4)-C-12/(CH4)-C-13 (non-deuterated) on Titan by remote sensing. Our spectra cover five widely-spaced latitudes, 65 degrees S to 71 degrees N and we have searched for both latitude variability of C-12/C-13 within a given species, and also for differences between the C-12/C-13 in the three gases. For CH4 alone, we find C-12/C-13 = 76.6 +/- 2.7 (1-sigma), essentially in agreement with the (CH4)-C-12/(CH4)-C-13 measured by the Huygens Gas Chromatograph/Mass Spectrometer instrument (GCMS) [Niemann, H.B., and 17 colleagues, 2005. Nature 438, 779-784]: 82.3 +/- 1.0, and also with measured values in (HCN)-C-13 and (CH3D)-C-13 by CIRS at lower precision [Bezard, B., Nixon, C., Kleiner, I., Jennings, D., 2007. Icarus 191, 397-400; Vinatier, S., Bezard, B., Nixon, C., 2007. Icarus 191, 712-721]. For the C-2 species, we find C-12/C-13 = 84.8 +/- 3.2 in C2H2 and 89.8 +/- 7.3 in C2H6, a possible trend of increasingly value with molecular mass, although these values are both compatible with the Huygens GCMS value to within error bars. There are no convincing trends in latitude. Combining all fifteen measurements, we obtain a value of C-12/C-13 = 80.8 +/- 2.0, also compatible with GCMS. Therefore, the evidence is mounting that C-12/C-13 is some 8% lower on Titan than on the Earth (88.9, inorganic standard), and lower than typical for the outer planets (88 +/- 7 [Sada, P.V., McCabe, G.H., Bjoraker, G.L., Jennings, D.E., Reuter, D.C., 1996. Astrophys. J. 472, 903-907]). There is no current model for this enrichment, and we discuss several mechanisms that may be at work. (C) 2008 Elsevier Inc. All rights reserved. C1 [Nixon, C. A.] NASA, Goddard Space Flight Ctr, Solar Syst Explorat Div, Planetary Syst Lab, Greenbelt, MD 20771 USA. [Vinatier, S.; Bezard, B.; Coustenis, A.] Observ Paris, LESIA, F-92195 Meudon, France. [Irwin, P. G. J.; Teanby, N. A.; de Kok, R.] Univ Oxford, Clarendon Lab, Atmospher Ocean & Planetary Phys, Oxford OX1 3PU, England. [Nixon, C. A.; Achterberg, R. K.] Univ Maryland, Dept Astron, College Pk, MD 20742 USA. RP Nixon, CA (reprint author), NASA, Goddard Space Flight Ctr, Solar Syst Explorat Div, Planetary Syst Lab, Code 693, Greenbelt, MD 20771 USA. EM conor.a.nixon@nasa.gov RI Nixon, Conor/A-8531-2009; Flasar, F Michael/C-8509-2012; Romani, Paul/D-2729-2012; Bjoraker, Gordon/D-5032-2012; Jennings, Donald/D-7978-2012; OI Nixon, Conor/0000-0001-9540-9121; Teanby, Nicholas/0000-0003-3108-5775; Irwin, Patrick/0000-0002-6772-384X NR 42 TC 29 Z9 29 U1 0 U2 1 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD JUN PY 2008 VL 195 IS 2 BP 778 EP 791 DI 10.1016/j.icarus.2008.01.012 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 304SD UT WOS:000256128500021 ER PT J AU Curtis, DB Hatch, CD Hasenkopf, CA Toon, OB Tolbert, MA McKay, CP Khare, BN AF Curtis, Daniel B. Hatch, Courtney D. Hasenkopf, Christa A. Toon, Owen B. Tolbert, Margaret A. McKay, Christopher P. Khare, Bishun N. TI Laboratory studies of methane and ethane adsorption and nucleation onto organic particles: Application to Titan's clouds SO ICARUS LA English DT Article DE Titan; atmospheres, chemistry; ices, IR spectroscopy; organic chemistry ID POLAR STRATOSPHERIC CLOUDS; OPTICAL-CONSTANTS; CIRRUS CLOUDS; NITRIC-ACID; ATMOSPHERE; HAZE; CONDENSATION; TEMPERATURES; GRAPHITE; SURFACE AB Titan, Saturn's largest moon, has a thick nitrogen/methane atmosphere. The temperature and pressure conditions in Titan's atmosphere are such that the methane vapor should condense near the tropopause to form clouds. Several ground-based measurements have observed sparse cloud-like features in Titan's atmosphere, while the Cassini mission to Saturn has provided large scale images of the clouds. However, Titan's cloud formation conditions remain poorly constrained. Heterogeneous nucleation (from the vapor phase onto a solid or liquid aerosol surface) greatly enhances cloud formation relative to homogeneous nucleation. In order to elucidate the cloud formation mechanism near the tropopause, we have performed laboratory measurements of the adsorption of methane and ethane onto solid organic particles (tholins) representative of Titan's photochemical haze. We find that monolayers of methane adsorb onto tholin particles at saturation ratios less than unity. We also find that solid methane nucleates onto the adsorbed methane at a saturation ratio of S = 1.07 +/- 0.008. This implies that Titan's methane clouds should form easily. This is consistent with recent measurements of the column of methane ruling out excessive methane supersaturation. In addition, we find ethane adsorbs onto tholin particles in a metastable phase prior to nucleation. However, ethane nucleation onto the adsorbed ethane occurs at a relatively high saturation ratio of S = 1.36 +/- 0.08. These findings are consistent with the recent report of polar ethane clouds in Titan's lower stratosphere. (C) 2008 Elsevier Inc. All rights reserved. C1 [Curtis, Daniel B.; Hatch, Courtney D.; Hasenkopf, Christa A.; Tolbert, Margaret A.] Univ Colorado, CIRES, Boulder, CO 80309 USA. [Curtis, Daniel B.; Hatch, Courtney D.; Tolbert, Margaret A.] Univ Colorado, Dept Chem & Biochem, Boulder, CO 80309 USA. [Hasenkopf, Christa A.; Toon, Owen B.] Univ Colorado, Dept Atmospher & Ocean Sci, Boulder, CO 80309 USA. [Toon, Owen B.] Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80309 USA. [McKay, Christopher P.; Khare, Bishun N.] NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. RP Tolbert, MA (reprint author), Univ Colorado, CIRES, Campus Box 216,CIRES Bldg,Rm 318, Boulder, CO 80309 USA. EM tolbert@cires.colorado.edu NR 34 TC 22 Z9 22 U1 0 U2 15 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD JUN PY 2008 VL 195 IS 2 BP 792 EP 801 DI 10.1016/j.icarus.2008.02.003 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 304SD UT WOS:000256128500022 ER PT J AU Lorenz, RD West, RD Johnson, WTK AF Lorenz, R. D. West, R. D. Johnson, W. T. K. TI Cassini RADAR constraint on Titan's winter polar precipitation SO ICARUS LA English DT Article DE Titan; Radar observations; meteorology ID CLOUDS; RAIN AB The Cassini RADAR instrument made a dedicated cloud backscatter observation near Titan's north pole, presently in winter darkness, to constrain the precipitation of material onto the surface. The detection limit is similar to 5 orders of magnitude above that expected in methane rainstorms, and rules out 'drizzle' of more than similar to 10 cm/yr, placing constraints on the winter accumulation of material on Titan's surface during polar winter. (C) 2008 Elsevier Inc. All rights reserved. C1 [Lorenz, R. D.] Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. [West, R. D.; Johnson, W. T. K.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Lorenz, RD (reprint author), Johns Hopkins Univ, Appl Phys Lab, 11100 Johns Hopkins Rd, Laurel, MD 20723 USA. EM ralph.lorenz@jhuapl.edu RI Lorenz, Ralph/B-8759-2016 OI Lorenz, Ralph/0000-0001-8528-4644 NR 23 TC 10 Z9 10 U1 0 U2 1 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD JUN PY 2008 VL 195 IS 2 BP 812 EP 816 DI 10.1016/j.icarus.2007.12.025 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 304SD UT WOS:000256128500024 ER PT J AU Colwell, JE Sture, S Cintala, M Durda, D Hendrix, A Goudie, T Curtis, D Ashcom, DJ Kanter, M Keohane, T Lemos, A Lupton, M Route, M AF Colwell, Joshua E. Sture, Stein Cintala, Mark Durda, Dan Hendrix, Amanda Goudie, Tyler Curtis, Darren Ashcom, Daniel J. Kanter, Matthew Keohane, Thomas Lemos, Andreas Lupton, Michael Route, Matthew TI Ejecta from impacts at 0.2-2.3 m/s in low gravity SO ICARUS LA English DT Article DE impact processes; collisional physics; planetesimals ID SATURNS F-RING; SOLAR NEBULA; PLANETESIMALS; DUST; MICROGRAVITY; COLLISIONS; ACCRETION; GROWTH; MODEL AB Collisions between planetary ring particles and in some protoplanetary disk environments occur at speeds below 10 m/s. The particles involved in these low-velocity collisions have negligible gravity and may be made of or coated with smaller dust grains and aggregates. We undertook microgravity impact experiments to better understand the dissipation of energy and production of ejecta in these collisions. Here we report the results of impact experiments of solid projectiles into beds of granular material at impact velocities from 0.2 to 2.3 m/s performed under near-weightless conditions on the NASA KC-135 Weightless Wonder V. Impactors of various densities and radii of I and 2 cm were launched into targets of quartz sand, JSC-1 lunar regolith simulant, and JSC-Mars-1 martian regolith simulant. Most impacts were at normal or near-normal incidence angles, though some impacts were at oblique angles. Oblique impacts led to much higher ejection velocities and ejecta masses than normal impacts. For normal incidence impacts, characteristic ejecta. velocities increase with impactor kinetic energy, KE, as approximately KE0.5. Ejecta masses could not be measured accurately due to the nature of the experiment, but qualitatively also increased with impactor kinetic energy. Some experiments were near the threshold velocity of 0.2 m/s identified in previous microgravity impact experiments as the minimum velocity needed-to produce ejecta [Colwell, J.E., 2003. Icarus 164, 188-196], and the experimental scatter is large at these low speeds in the airplane experiment. A more precise exploration of the transition from low-ejecta-mass impacts to high-ejecta-mass impacts requires a longer and smoother period of reduced gravity. Coefficient of restitution measurements are not possible due to the varying acceleration of the airplane throughout the experiment. (C) 2008 Elsevier Inc. All rights reserved. C1 [Colwell, Joshua E.] Univ Cent Florida, Dept Phys, Orlando, FL 32816 USA. [Sture, Stein] Univ Colorado, Dept Civil Environm & Architectural Engn, Boulder, CO 80309 USA. [Cintala, Mark] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. [Durda, Dan] SW Res Inst, Boulder, CO 80302 USA. [Hendrix, Amanda] Jet Prop Lab, Pasadena, CA 91109 USA. [Goudie, Tyler; Curtis, Darren; Ashcom, Daniel J.; Kanter, Matthew; Keohane, Thomas; Lemos, Andreas; Lupton, Michael; Route, Matthew] Univ Colorado, LASP, Boulder, CO 80309 USA. RP Colwell, JE (reprint author), Univ Cent Florida, Dept Phys, 4000 Cent Florida Blvd, Orlando, FL 32816 USA. EM jcolwell@physics.ucf.edu NR 28 TC 13 Z9 13 U1 0 U2 7 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD JUN PY 2008 VL 195 IS 2 BP 908 EP 917 DI 10.1016/j.icarus.2007.12.019 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 304SD UT WOS:000256128500033 ER PT J AU Chapin, E Chen, CW AF Chapin, Elaine Chen, Curtis W. TI Along-track interferometry for ground moving target indication SO IEEE AEROSPACE AND ELECTRONIC SYSTEMS MAGAZINE LA English DT Article AB Synthetic aperture radar (SAR) along-track interferometry (ATI) has been used extensively to measure ocean surface currents. Given its ability to measure small velocities (similar to 10 cm/s) of relatively radar-dark water surfaces, there is great potential that this technique can be adapted for ground moving target indication (GMTI) applications, particularly as a method for detecting very slow targets with small radar cross-sections. Herein, we describe preliminary results from an ATI GMTI experiment. The SAR data described were collected by the dual-frequency NASA/JPL airborne radar in its standard dual-baseline ATI mode. The radar system imaged a variety of control targets including a pickup truck, sport utility vehicles, passenger cars, a bicycle, and pedestrians over multiple flight passes. The control targets had horizontal velocities of less than 5 m/s. The cross-sections of the targets were not purposely enhanced, although the targets' reflectivities may have been affected by the existence of the GPS equipment used to record the targets' positions. Single-look and multiple-look interferograms processed to the full azimuth resolution were analyzed. In the data processed to date, all of the targets were observed by visual inspection in at least one of the four combinations of dual-frequency, dual-baseline interferometric data. This extremely promising result demonstrates the potential of ATI for GMTI applications. C1 [Chapin, Elaine; Chen, Curtis W.] CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA. RP Chapin, E (reprint author), CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA. NR 6 TC 15 Z9 19 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0885-8985 J9 IEEE AERO EL SYS MAG JI IEEE Aerosp. Electron. Syst. Mag. PD JUN PY 2008 VL 23 IS 6 BP 19 EP 24 DI 10.1109/MAES.2008.4558004 PG 6 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA 319WP UT WOS:000257196000004 ER PT J AU Fung, AK Gaier, T Samoska, L Deal, WR Radisic, V Mei, XB Yoshida, W Liu, PS Uyeda, J Barsky, M Lai, R AF Fung, A. K. Gaier, T. Samoska, L. Deal, W. R. Radisic, V. Mei, X. B. Yoshida, W. Liu, P. S. Uyeda, J. Barsky, M. Lai, R. TI First on-wafer power characterization of MMIC amplifiers at sub-millimeter wave frequencies SO IEEE MICROWAVE AND WIRELESS COMPONENTS LETTERS LA English DT Article DE amplifier; monolithic microwave integrated circuit (MMIC); MM-wave; power measurement ID 35-NM; TECHNOLOGY AB We present on-wafer power measurements of 35 nm gate length InP HEMT amplifiers at 330 GHz. Various amplifiers are examined. The maximum output power of 1.78 mW is measured from a three stage amplifier. Additional output power may be possible but limited by our input power source level to saturate amplifiers. This result is the highest frequency on-wafer power measurement we are aware of reported to date, and demonstrates the technique we utilize to be a fast method of evaluating power performance of submillimeter wave amplifiers without the need to package devices. C1 [Fung, A. K.; Gaier, T.; Samoska, L.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Deal, W. R.; Radisic, V.; Mei, X. B.; Yoshida, W.; Liu, P. S.; Uyeda, J.; Barsky, M.; Lai, R.] Northrop Grumman Corp, Redondo Beach, CA 90278 USA. RP Fung, AK (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM andy.k.fung@jpl.nasa.gov NR 7 TC 4 Z9 4 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 1531-1309 J9 IEEE MICROW WIREL CO JI IEEE Microw. Wirel. Compon. Lett. PD JUN PY 2008 VL 18 IS 6 BP 419 EP 421 DI 10.1109/LMWC.2008.922713 PG 3 WC Engineering, Electrical & Electronic SC Engineering GA 311UD UT WOS:000256625000015 ER PT J AU Goebel, K Yan, WZ AF Goebel, Kai Yan, Weizhong TI Correcting Sensor Drift and Intermittency Faults With Data Fusion and Automated Learning SO IEEE SYSTEMS JOURNAL LA English DT Article DE Data fusion; drift fault; fuzzy fusion; intermittency; intermittent fault; sensor validation; soft fault AB Many fault detection algorithms deal with fault signatures that manifest themselves as step changes. While detection of these step changes can be difficult due to noise and other complicating factors, detecting slowly developing faults is usually even more complicated. Tradeoffs between early detection and false positive avoidance are more difficult to establish. Often times, slow drift faults go completely undetected because the monitoring systems assume that they are ordinary system changes and some monitoring schemes may adapt to the changes. Where redundant sensors are used, a drifting sensor may cause the logic to latch on to the "bad" sensor. Another problem may be intermittent sensors faults where the detection logic is too sluggish to recognize a problem before the sensor has returned to seemingly normal behavior. To address these classes of problems, we introduce here a set of algorithms that learns to avoid the bad sensor, thus indirectly recognizing the aberrant sensor. We combine advanced sensor validation techniques with learning. The sensor validation is inspired by fuzzy principles. The parameters of this algorithm are learned using competing optimization approaches. We compare the results from a particle swarm optimization approach with those obtained from genetic algorithms. Results are shown for an application in the transportation industry. C1 [Goebel, Kai] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. [Yan, Weizhong] GE Global Res, Niskayuna, NY 12309 USA. [Yan, Weizhong] GE Global Res Ctr, Ind Artificial Intelligence Lab, Niskayuna, NY USA. RP Goebel, K (reprint author), NASA, Ames Res Ctr, MS 269-4, Moffett Field, CA 94035 USA. EM kai.goebel@nasa.gov; yan@research.ge.com NR 32 TC 14 Z9 15 U1 0 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1932-8184 J9 IEEE SYST J JI IEEE Syst. J. PD JUN PY 2008 VL 2 IS 2 BP 189 EP 197 DI 10.1109/JSYST.2008.925262 PG 9 WC Computer Science, Information Systems; Engineering, Electrical & Electronic; Operations Research & Management Science; Telecommunications SC Computer Science; Engineering; Operations Research & Management Science; Telecommunications GA V10ND UT WOS:000207469800003 ER PT J AU Marshall, WS Rey, CM Dietz, AJ Audette, WE Hilderbrand, JK Winter, DS Petro, AJ AF Marshall, W. Scott Rey, Christopher M. Dietz, Anthony J. Audette, William E. Hilderbrand, Joshua K. Winter, D. Scott Petro, Andrew J. TI Design, fabrication and testing of an HTS magnet and flow cooling system for space-based applications SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 20th International Conference on Magnet Technology CY AUG 27-31, 2007 CL Philadelphia, PA SP IEEE Council Appl Superconductiv DE BSCCO; flow cooling; HTS; superconducting magnet AB A team comprised of the Tai-Yang Research Company, Creare, Inc., and the Advanced Space Propulsion Laboratory at NASA has designed, fabricated and tested a high-temperature superconducting magnet and flow cooling system for a space propulsion application. The magnet bore is 16 cm dia., 5.5 cm long, and generates 0.5 T, with a design operating current of 126 A. The magnet is wound with brass laminated 1 G BSCCO conductor, epoxy impregnated, then thermally connected to a flow cooling loop with a compressor, recuperator and GM cryocooler. Flow conditions are selected to simulate operation with a space proven turbo-Brayton cryocooler. This test demonstrates that design and integration of an HTS magnet with flow cooling is feasible, and offers the advantages of compactness, low weight, high efficiency and high reliability. Design details of the magnet and cooling system and results of successful system qualification tests are reported. C1 [Marshall, W. Scott; Rey, Christopher M.] Tai Yang Res Co, Knoxville, TN 37922 USA. [Dietz, Anthony J.; Audette, William E.; Hilderbrand, Joshua K.] Creare Res & Dev Inc, Hanover, NH 03755 USA. [Winter, D. Scott; Petro, Andrew J.] Adv Space Propuls Lab, Houston, TX USA. [Winter, D. Scott; Petro, Andrew J.] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Marshall, WS (reprint author), Tai Yang Res Co, Knoxville, TN 37922 USA. EM wsmarshall@tai-yang.com NR 3 TC 1 Z9 1 U1 1 U2 6 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD JUN PY 2008 VL 18 IS 2 BP 969 EP 971 DI 10.1109/TASC.2008.922531 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 311UK UT WOS:000256625700213 ER PT J AU Ghaffarian, R AF Ghaffarian, Reza TI Thermal cycle reliability and failure mechanisms of CCGA and PBGA assemblies with and without corner staking SO IEEE TRANSACTIONS ON COMPONENTS AND PACKAGING TECHNOLOGIES LA English DT Article DE ball grid array (BGA); ceramic column grid array (CCGA); column grid array (CGA); inspection; plastic ball grid array (PBGA); solder joint; stake; thermal cycle AB Area array packages (AAPs) with 1.27 mm pitch have been the packages of choice for commercial applications; they are now starting to be implemented for use in military and aerospace applications. Thermal cycling characteristics of plastic ball grid array (PBGA) and chip scale package assemblies, because of their wide usage for commercial applications, have been extensively reported on in literature. Thermal cycling represents the on-off environmental condition for most electronic products and therefore is a key factor that defines reliability. However, very limited data is available for thermal cycling behavior of ceramic packages commonly used for the aerospace applications. For high reliability applications, numerous AAPs are available with an identical design pattern both in ceramic and plastic packages. This paper compares assembly reliability of ceramic and plastic packages with the identical inputs/outputs (I/Os) and pattern. The ceramic package was in the form of ceramic column grid array (CCGA) with 560 I/Os peripheral array with the identical pad design as its plastic counterpart. The effects of the following key parameters on reliability of both CCGA and PBGA assemblies were investigated: 1) thermal cycle ranges, -50 degrees C/75 degrees C, -55 degrees C/100 degrees C, and -55 degrees C/125 degrees C; 2) corner staking on failure mechanisms for two thermal cycle profiles, -55 degrees C/125 degrees C and -50 degrees C/75 degrees C; 3) package interchangeability, i.e., using PBGA package on CCGA pad design with a larger pad. Packages were assembled on polyimide boards and their daisy chains were continuously monitored. Optical photomicrographs were taken at various thermal cycle intervals to document damage progress and behavior. Representative samples along with their cross-sectional photomicrographs at higher magnification, taken by scanning electron microscopy and analyzed by energy dispersive X-ray, are also presented. The inspection documents were used to determine crack propagation and failure analyses for packages with and without corner staking. In assemblies with corner staking adhesive, a transition in failure from corner columns to center columns was observed when maximum temperature in thermal cycling profiles changed. This is a new failure mechanism not reported on in literature. Finite element analysis (FEA) was used to predict such global failure mode changes. FEA findings are also presented. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Ghaffarian, R (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM reza.ghaffrian@jpl.nasa.gov NR 18 TC 8 Z9 9 U1 3 U2 11 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 1521-3331 J9 IEEE T COMPON PACK T JI IEEE Trans. Compon. Packaging Technol. PD JUN PY 2008 VL 31 IS 2 BP 285 EP 296 DI 10.1109/TCAPT.2008.921626 PG 12 WC Engineering, Manufacturing; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 311EX UT WOS:000256584600007 ER PT J AU Lasne, Y Paillou, P Freeman, A Farr, T McDonald, KC Ruffie, G Malezieux, JM Chapman, B Demontoux, F AF Lasne, Yannick Paillou, Philippe Freeman, Anthony Farr, Tom McDonald, Kyle C. Ruffie, Gilles Malezieux, Jean-Marie Chapman, Bruce Demontoux, Francois TI Effect of salinity on the dielectric properties of geological materials: Implication for soil moisture detection by means of radar remote sensing SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE dielectric mixing model; evaporites; integral equation model (IEM); polarimetry; radar backscattering; salinity; soil moisture; synthetic aperture radar (SAR) ID WET SUBSURFACE STRUCTURES; POLARIMETRIC L-BAND; MICROWAVE-FREQUENCIES; MULTIPLE-SCATTERING; SURFACE-ROUGHNESS; PHASE SIGNATURE; BARE SOIL; IEM MODEL; SAR; BACKSCATTERING AB We consider the exploitation of dielectric properties of saline deposits for the detection and mapping of moisture in and regions on both Earth and Mars. We present simulated and experimental study in order to assess the effect of salinity on the complex permittivity of geological materials and, therefore, on the radar backscattering coefficient in the [1-7 GHz] frequency range. Laboratory measurements are performed on sand/sodium chloride aqueous mixtures using a vectorial network analyzer coupled to an open-ended coaxial dielectric probe. We aim at calibrating and validating semiempirical dielectric mixing models. In particular, we evaluated the dependence of the real and imaginary parts of complex permittivity on the microwave frequency, water content, and salinity. Our results confirm that if the real part is mainly affected by the moisture content, the imaginary part is more sensitive to salinity. In addition to the classic formulas of mixing models, the ionic-conductivity losses, which are due to mobile ions in the saline solution, are taken into account in order to better assess the effect of salinity on the dielectric properties of mixtures. Dielectric mixing models are then used as input parameters for the simulation of the radar backscattering coefficients by means of an analytical model: the integral equation model. Simulation results show that salinity should have a significant impact on the radar backscattering recorded in synthetic aperture radar data in terms of the magnitude of the backscattering coefficient. Moreover, our results suggest that VV polarization provides a greater sensitivity to salinity than HH polarization. C1 [Lasne, Yannick; Paillou, Philippe] Observ Aquitain Sci Univers, F-33270 Floirac, France. [Freeman, Anthony; Farr, Tom; McDonald, Kyle C.; Chapman, Bruce] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Ruffie, Gilles; Demontoux, Francois] Ecole Natl Super Chim Phys Bordeaux, IMS, UMR5218, F-33607 Pessac, France. [Malezieux, Jean-Marie] EGIG Bordeaux Inst 3, F-33607 Pessac, France. RP Lasne, Y (reprint author), Observ Aquitain Sci Univers, F-33270 Floirac, France. EM lasne@enscpb.fr; paillou@obs.u-bordeaux1.fr; tony.freeman@jpl.nasa.gov; tom.farr@jpl.nasa.gov; kyle.mcdonald@jpl.nasa.gov; g.ruffie@enscpb.fr; jmmalez@egid.u-bordeaux.fr; bruce.chapman@jpl.nasa.gov OI Farr, Thomas/0000-0001-5406-2096 NR 50 TC 31 Z9 35 U1 4 U2 15 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD JUN PY 2008 VL 46 IS 6 BP 1674 EP 1688 DI 10.1109/TGRS.2008.916220 PG 15 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 303QR UT WOS:000256056100011 ER PT J AU Jedlovec, GJ Haines, SL LaFontaine, FJ AF Jedlovec, Gary J. Haines, Stephanie L. LaFontaine, Frank J. TI Spatial and temporal varying thresholds for cloud detection in GOES imagery SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE atmospheric measurements; clouds; meteorology; remote sensing ID GOES SOUNDER DATA; RETRIEVAL ALGORITHM; GOES SCENES; GOES-VAS; SATELLITE; TEMPERATURE; MODIS; COVER; TRENDS; ISCCP AB A new cloud detection technique has been developed and applied to GOES-12 Imager data. The bispectral composite threshold (BCT) technique uses only the 11- and 3.9-mu m channels, and composite imagery generated from these channels, in a four-step cloud detection procedure to produce a binary cloud mask at single-pixel resolution. An innovative aspect of this algorithm is the use of 20-day composites of the 11- and the 11-3.9-mu m channel difference imagery to represent spatially and temporally varying clear-sky thresholds for the bispectral cloud tests. The BCT cloud detection technique has been validated against a "truth" data set generated by the manual determination of the sky conditions from available satellite imagery for four seasons during 2003-2004. The day-and-night algorithm has been shown to determine the correct sky conditions 87.6% of the time (on average) over the eastern two-thirds of the U.S. and surroundings oceans. The incorrectly determined conditions arose from missing clouds 8.9% of the time or from overdetermining clouds 3.5% of the time. Nearly 82% of the misses came in the presence of low clouds. Only small variations in algorithm performance occurred between day-night, land-ocean, and between seasons. The algorithm performed best in the warmer seasons (90.9% correct during the summer versus 81.8% correct in the winter season) and during the day, when the solar illumination provides enhanced surface atmospheric cloud contrast in the infrared channels, and least well during the winter season. The algorithm was found to slightly underdetermine clouds at night and during times of low sun angle and tends to be cloud conservative during the day, particularly in the summertime. C1 [Jedlovec, Gary J.] NASA, Marshall Space Flight Ctr, Natl Space Sci & Technol Ctr, Earth Sci Off, Huntsville, AL 35805 USA. [Haines, Stephanie L.] Univ Alabama, Ctr Earth Syst Sci, Huntsville, AL 35805 USA. [LaFontaine, Frank J.] Raytheon Co, Natl Space Sci & Technol Ctr, Huntsville, AL 35805 USA. RP Jedlovec, GJ (reprint author), NASA, Marshall Space Flight Ctr, Natl Space Sci & Technol Ctr, Earth Sci Off, Huntsville, AL 35805 USA. EM gary.jedlovec@nasa.gov NR 36 TC 26 Z9 29 U1 0 U2 11 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD JUN PY 2008 VL 46 IS 6 BP 1705 EP 1717 DI 10.1109/TGRS.2008.916208 PG 13 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 303QR UT WOS:000256056100014 ER PT J AU Durand, M Kim, EJ Margulis, SA AF Durand, Michael Kim, Edward J. Margulis, Steven A. TI Quantifying uncertainty in modeling snow microwave radiance for a mountain snowpack at the point-scale, including stratigraphic effects SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE hydrology; microwave radiometry; remote sensing; snow ID GROUND-BASED OBSERVATIONS; WETTING FRONT ADVANCE; LAND-SURFACE MODEL; WATER EQUIVALENT; EMISSION MODEL; BRIGHTNESS TEMPERATURES; LAYERED SNOWPACKS; DATA ASSIMILATION; WESTERN CANADA; GRAIN-SIZE AB Merging microwave radiances and modeled estimates of snowpack states in a data assimilation scheme is a potential method for snowpack characterization. A radiance assimilation scheme for snow requires a land surface model (LSM) coupled to a radiative transfer model (RTM). In this paper, we explore the degree of model fidelity required in order for radiance assimilation to yield benefits for snowpack characterization. Specifically, we characterize the uncertainty of Microwave Emission Model for Layered Snowpacks (MEMLS) radiance predictions by quantifying model accuracy and sensitivity to the following: 1) the LSM snowpack layering scheme and 2) the properties of the snow layers, including melt-refreeze ice layers. MEMLS was consistent with the measured brightness temperatures at 18.7 and 36.5 GHz with a bias (mean absolute error) of -0.1 K (3.1 K) for the vertical polarization and 3.4 K (9.3 K) for the horizontal polarization. An error in the predictions at horizontal polarization is due to uncertainty in ice-layer properties. It was found that in order for predicted brightness temperatures from the coupled LSM and RTM to be adequate for radiance assimilation purposes, the following must be satisfied: 1) the LSM snowpack layering scheme must accurately represent the stratigraphic snowpack layers; 2) dynamics of melt-refreeze ice layers must be modeled explicitly, and the predicted density of melt-refreeze layers must be accurate within +/- 40 kg center dot m(-3); and 3) the MEMLS correlation length must be predicted within +/- 0.016 mm, or effective optical grain diameter must be predicted within +/- 0.045 mm. Recommendations for future field measurements are made. C1 [Durand, Michael] Ohio State Univ, Byrd Polar Res Ctr, Columbus, OH 43210 USA. [Kim, Edward J.] NASA, Goddard Space Flight Ctr, Hydrospher & Biospher Sci Lab, Greenbelt, MD 20771 USA. [Margulis, Steven A.] Univ Calif Los Angeles, Dept Civil & Environm Engn, Los Angeles, CA 90095 USA. RP Durand, M (reprint author), Ohio State Univ, Byrd Polar Res Ctr, Columbus, OH 43210 USA. EM durand.8@osu.edu; ed.kim@nasa.gov; margulis@seas.ucla.edu RI Durand, Michael/D-2885-2013 NR 64 TC 66 Z9 66 U1 0 U2 11 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD JUN PY 2008 VL 46 IS 6 BP 1753 EP 1767 DI 10.1109/TGRS.2008.916221 PG 15 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 303QR UT WOS:000256056100019 ER PT J AU Xiong, XX Chiang, KF Wu, AS Barnes, WL Guenther, B Salomonson, VV AF Xiong, Xiaoxiong Chiang, Kwo-Fu Wu, Aisheng Barnes, William L. Guenther, Bruce Salomonson, Vincent V. TI Multiyear on-orbit calibration and performance of Terra MODIS thermal emissive bands SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE blackbody (BB); calibration; Moderate Resolution Imaging Spectroradiometer (MODIS); radiometer; Terra; thermal emissive bands (TEBs) ID RESOLUTION IMAGING SPECTRORADIOMETER; REFLECTIVE SOLAR BANDS; RADIOMETRIC CALIBRATION; TEMPERATURE; VALIDATION; ALGORITHM; WATER; AQUA AB Since its launch in December 1999, Terra MODIS has been making continuous Earth observations for more than seven years. It has produced a broad range of land, ocean, and atmospheric science data products for improvements in studies of global climate and environmental change. Among its 36 spectral bands, there are 20 reflective solar bands and 16 thermal emissive bands (TEBs). MODIS TEBs cover the mid-wave infrared and long-wave infrared spectral regions with wavelengths from 3.7 to 14.4 mu m. They are calibrated on-orbit using an onboard black-body (BB) with its temperature measured by a set of thermistors on a scan-by-scan basis. This paper will provide a brief overview of MODIS TEB calibration and characterization methodologies and illustrate onboard BB functions and TEB performance over more than seven years of on-orbit operation and calibration. Discussions will be focused on TEB detector short-term stability and noise characterization and changes in long-term response (or system gain). Results show that Terra MODIS BB operation has been extremely stable since launch. When operated at its nominal controlled temperature of 290 K, the BB temperature variation is typically less than +/- 0.30 mK on a scan-by-scan basis, and there has been no time-dependent temperature drift. In addition to excellent short-term stability, most TEB detectors continue to meet or exceed their specified noise characterization requirements, thus enabling calibration accuracy and science data product quality to be maintained. Excluding the noisy detectors identified prelaunch and those that occurred postlaunch, the changes in TEB responses have been less than 0.7% on an annual basis. The optical leak corrections applied to bands 32-36 have been effective and stable over the entire mission. C1 [Xiong, Xiaoxiong] NASA, Goddard Space Flight Ctr, Sci & Explorat Directorate, Greenbelt, MD 20771 USA. [Chiang, Kwo-Fu; Wu, Aisheng] Sci Syst & Applicat Inc, Lanham, MD 20706 USA. [Barnes, William L.; Guenther, Bruce] Univ Maryland Baltimore Cty, Baltimore, MD 21250 USA. [Salomonson, Vincent V.] Univ Utah, Dept Meteorol, Salt Lake City, UT 84112 USA. [Salomonson, Vincent V.] Univ Utah, Dept Geog, Salt Lake City, UT 84112 USA. [Salomonson, Vincent V.] NASA, Goddard Space Flight Ctr, Div Earth Sci, Greenbelt, MD 20771 USA. RP Xiong, XX (reprint author), NASA, Goddard Space Flight Ctr, Sci & Explorat Directorate, Greenbelt, MD 20771 USA. NR 27 TC 60 Z9 60 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD JUN PY 2008 VL 46 IS 6 BP 1790 EP 1803 DI 10.1109/TGRS.2008.916217 PG 14 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 303QR UT WOS:000256056100023 ER PT J AU Fung, A Samoska, L Chattopadhyay, G Gaier, T Kangaslahti, P Pukala, D Oleson, C Denning, A Lau, YN AF Fung, Andy Samoska, Lorene Chattopadhyay, Goutam Gaier, Todd Kangaslahti, Pekka Pukala, David Oleson, Charles Denning, Anthony Lau, Yuenie TI Two-port vector network analyzer measurements up to 508 GHz SO IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT LA English DT Article DE measurement; millimeter-wave measurements; monolithic microwave integrated circuit (MMIC) amplifiers; MMICs; scattering parameter measurement; submillimeter-wave amplifiers; submillimeter-wave circuits; submillimeter-wave measurements; submillimeter-wave technology; submillimeter-wave transistors; submillimeter-wave waveguides ID MMIC AMPLIFIER; TECHNOLOGY; 35-NM AB We present new results for a two-port vector network analyzer swept-frequency test set for the 325-508 GHz frequency band. The calibrated dynamic range performance in the full frequency band is discussed. Using a line-reflect-line calibration procedure, the dynamic ranges for return and insertion losses of better than -20 and -35 dB, respectively, are achieved. We examine the performance of the calibrated test set for the first time by measuring S-parameters of passive waveguide components and comparing data with electromagnetic simulations. C1 [Fung, Andy; Samoska, Lorene; Chattopadhyay, Goutam; Gaier, Todd; Kangaslahti, Pekka; Pukala, David] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Oleson, Charles; Denning, Anthony; Lau, Yuenie] Oleson Microwave Labs Inc, Morgan Hill, CA 95037 USA. RP Fung, A (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM andy.k.fung@jpl.nasa.gov NR 13 TC 6 Z9 6 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9456 J9 IEEE T INSTRUM MEAS JI IEEE Trans. Instrum. Meas. PD JUN PY 2008 VL 57 IS 6 BP 1166 EP 1170 DI 10.1109/TIM.2007.915125 PG 5 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 324TF UT WOS:000257541600011 ER PT J AU Samoska, L Deal, WR Chattopadhyay, G Pukala, D Fung, A Gaier, T Soria, M Radisic, V Mei, XB Lai, R AF Samoska, Lorene Deal, William R. Chattopadhyay, Goutam Pukala, David Fung, Andy Gaier, Todd Soria, Mary Radisic, Vesna Mei, Xiaobing Lai, Richard TI A submillimeter-wave HEMT amplifier module with integrated waveguide transitions operating above 300 GHz SO IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES LA English DT Article DE amplifier; HEMT; millimeter wave; monolithic millimeter-wave integrated circuit (MMIC); sub-millimeter wave ID MMIC AMPLIFIER; TECHNOLOGY; 35-NM; RECEIVER; GAIN; BAND AB In this paper, we report on the first demonstration of monolithically integrated waveguide transitions in a submillimeter-wave monolithic integrated circuit (S-MMIC) amplifier module. We designed the module for a targeted frequency range of 300-350 GHz, using WR2.2 for the input and output waveguides. The waveguide module utilizes radial E-plane transitions from S-MMIC to waveguide. We designed back-to-back radial probe transitions separated by thru transmission lines to characterize the module, and have incorporated the radial E-plane transitions with an S-MMIC amplifier, fabricated monolithically as a single chip. The chip makes use of an S-MMIC process and amplifier design from the Northrop Grumman Corporation, Redondo Beach, CA, using 35-nm gate-length InP transistors. The integrated module design eliminates the need for wire bonds in the RF signal path, and enables a drop-in approach for minimal assembly. The waveguide module includes a channel design, which optimizes the E-plane probe bandwidth to compensate for an S-MMIC width, which is larger than the waveguide b dimension, and is compatible with S-MMIC fabrication and design rules. This paper demonstrates for the first time that waveguide-based S-MMIC amplifier modules with integrated waveguide transitions can be successfully operated at submillimeter-wave frequencies. C1 [Samoska, Lorene; Chattopadhyay, Goutam; Pukala, David; Fung, Andy; Gaier, Todd; Soria, Mary] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Deal, William R.; Radisic, Vesna; Mei, Xiaobing; Lai, Richard] Northrop Grumman Corp, Redondo Beach, CA 92078 USA. RP Samoska, L (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM lorene.samoska@jpl.nasa.gov; william.r.deal@ngc.com; goutam.chattopadhyay@jpl.nasa.gov; david.pukala@jpl.nasa.gov; andy.k.fung@jpl.nasa.gov; todd.c.gaier@jpl.nasa.gov; mmwells@jpl.nasa.gov; vesna.radisic@ngc.com; Gerry.Mei@ngc.com; Richard.Lai@ngc.com NR 23 TC 26 Z9 26 U1 2 U2 6 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9480 J9 IEEE T MICROW THEORY JI IEEE Trans. Microw. Theory Tech. PD JUN PY 2008 VL 56 IS 6 BP 1380 EP 1388 DI 10.1109/TMTT.2008.923353 PG 9 WC Engineering, Electrical & Electronic SC Engineering GA 314HO UT WOS:000256800700009 ER PT J AU Montes, EJ Reed, RA Pellish, JA Alles, ML Schrimpf, RD Weller, RA Varadharajaperumal, M Niu, GF Sutton, AK Diestelhorst, R Espinel, G Krithivasan, R Comeau, JP Cressler, JD Marshall, PW Vizkelethy, G AF Montes, Enrique J. Reed, Robert A. Pellish, Jonathan A. Alles, Michael L. Schrimpf, Ronald D. Weller, Robert A. Varadharajaperumal, Muthubalan Niu, Guofu Sutton, Akil K. Diestelhorst, Ryan Espinel, Gustavo Krithivasan, Ramkumar Comeau, Jonathan P. Cressler, John D. Marshall, Paul. W. Vizkelethy, Gyorgy TI Single event upset mechanisms for low-energy-deposition events in SiGeHBTs SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 15th International Workshop on Room-Temperature Semiconductor X- and Gamma-Ray Detectors CY OCT 29-NOV 04, 2006 CL San Diego, CA DE deep trench isolation (DTI); HBT; IBICC; silicon germanium (SiGe); single event upset (SEU); TCAD ID INDUCED CHARGE COLLECTION; CROSS-SECTION; DIGITAL LOGIC; SEU; CIRCUIT; RATES; BEAM AB Microbeam measurements and TCAD simulations are used to examine the effects of ion angle of incidence on the charge collected from events occurring in a Silicon Germanium (SiGe) Heterojunction Bipolar Transistor (HBT). The results identify the geometrically driven charge-collection mechanisms that dominate the low LET broad beam SEU response. The deep trench isolation that surrounds the transistor significantly modulates the charge transport and, therefore, the charge collected by the collector. A new way of estimating critical charge, Q-it for upset in SiGe HBT circuits is proposed based on TCAD simulation results and measured broadbeam data. C1 [Montes, Enrique J.; Reed, Robert A.; Pellish, Jonathan A.; Alles, Michael L.; Schrimpf, Ronald D.; Weller, Robert A.] Vanderbilt Univ, Dept Elect Engn & Comp Sci, Nashville, TN 37235 USA. [Varadharajaperumal, Muthubalan; Niu, Guofu] Auburn Univ, Auburn, AL 36849 USA. [Sutton, Akil K.; Diestelhorst, Ryan; Espinel, Gustavo; Krithivasan, Ramkumar; Comeau, Jonathan P.] Georgia Inst Technol, Atlanta, GA 30332 USA. [Marshall, Paul. W.] NASA GSFC, Brookneal, VA 24528 USA. [Vizkelethy, Gyorgy] Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Montes, EJ (reprint author), Vanderbilt Univ, Dept Elect Engn & Comp Sci, 221 Kirkland Hall, Nashville, TN 37235 USA. EM enrique.j.montes@vanderbilt.edu RI Pellish, Jonathan/A-8591-2008; Krithivasan, Ramkumar/D-3549-2011; Schrimpf, Ronald/L-5549-2013 OI Schrimpf, Ronald/0000-0001-7419-2701 NR 17 TC 10 Z9 10 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD JUN PY 2008 VL 55 IS 3 BP 1581 EP 1586 DI 10.1109/TNS.2007.893920 PN 3 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 316RR UT WOS:000256967900003 ER PT J AU De Geronimo, G Chen, W Fried, J Li, Z Pinelli, DA Rehak, P Vernon, E Gaskin, JA Ramsey, BD Anelli, G AF De Geronimo, Gianluigi Chen, Wei Fried, Jack Li, Zheng Pinelli, Donald A. Rehak, Pavel Vernon, Emerson Gaskin, Jessica A. Ramsey, Brian D. Anelli, Giovanni TI Front-end ASIC for high resolution X-ray spectrometers SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 15th International Workshop on Room-Temperature Semiconductor X- and Gamma-Ray Detectors CY OCT 29-NOV 04, 2006 CL San Diego, CA DE ASIC; SDD; X-ray spectrometer ID SILICON DRIFT DETECTORS; CHARGE-SENSITIVE PREAMPLIFIER; CONTINUOUS RESET; READOUT CIRCUIT; JFET; CHAMBER AB We present an application specific integrated circuit (ASIC) for high-resolution X-ray spectrometers. The ASIC is designed to read out signals from a pixelated silicon drift detector (SDD). Each hexagonal pixel has an area of 15 mm(2) and an anode capacitance of less than 100 fF. There is no integrated Field Effect transistor (FET) in the pixel, rather, the readout is done by wire-bonding the anodes to the inputs of the ASIC. The ASIC provides 14 channels of low-noise charge amplification, high-order shaping with baseline stabilization, and peak detection with analog memory. The readout is sparse and based on low voltage differential signaling. An interposer provides all the interconnections required to bias and operate the system. The channel dissipates 1.6 mW. The complete 14-pixel unit covers an area of 210 mm(2), dissipates 12 mW cm(-2), and can be tiled to cover an arbitrarily large detection area. We measured a preliminary resolution of 172 eV at -35 degrees C on the 6 keV peak of a Fe-55 source. C1 [De Geronimo, Gianluigi; Chen, Wei; Fried, Jack; Li, Zheng; Pinelli, Donald A.; Rehak, Pavel; Vernon, Emerson] Brookhaven Natl Lab, Instrumentat Div, Upton, NY 11973 USA. [Gaskin, Jessica A.; Ramsey, Brian D.] NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. [Anelli, Giovanni] CERN, Geneva, Switzerland. RP De Geronimo, G (reprint author), Brookhaven Natl Lab, Instrumentat Div, Upton, NY 11973 USA. EM degeronimo@bnl.gov NR 29 TC 15 Z9 15 U1 1 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD JUN PY 2008 VL 55 IS 3 BP 1604 EP 1609 DI 10.1109/TNS.2008.922218 PN 3 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 316RR UT WOS:000256967900006 ER PT J AU Jin, HQ Chapman, B Huang, L Mey, DA Reichstein, T AF Jin, Haoqiang Chapman, Barbara Huang, Lei Mey, Dieter an Reichstein, Thomas TI Performance evaluation of a multi-zone application in different OpenMP approaches SO INTERNATIONAL JOURNAL OF PARALLEL PROGRAMMING LA English DT Article; Proceedings Paper CT 3rd International Workshop on OpenMP (IWOMP) CY JUN 03-07, 2007 CL Beijing, PEOPLES R CHINA DE multi-level parallelism; OpenMP extensions; performance evaluation AB We describe a performance study of a multi-zone application benchmark implemented in several OpenMP approaches that exploit multi-level parallelism and deal with unbalanced workload. The multi-zone application was derived from the well-known NAS Parallel Benchmarks (NPB) suite that involves flow solvers on collections of loosely coupled discretization meshes. Parallel versions of this application have been developed using the Subteam concept and Workqueuing model as extensions to the current OpenMP. We examine the performance impact of these extensions to OpenMP and compare with hybrid and nested OpenMP approaches on several large parallel systems. C1 [Jin, Haoqiang] NASA, Ames Res Ctr, NAS Div, Moffett Field, CA 94035 USA. [Chapman, Barbara; Huang, Lei] Univ Houston, Dept Comp Sci, Houston, TX 77004 USA. [Mey, Dieter an; Reichstein, Thomas] Rhein Westfal TH Aachen, Comp & Commun Ctr, Aachen, Germany. RP Jin, HQ (reprint author), NASA, Ames Res Ctr, NAS Div, M-S 258-1, Moffett Field, CA 94035 USA. EM hjin@nas.nasa.gov; chapman@cs.uh.edu; leihuang@cs.uh.edu; anmey@rz.rwth-aachen.de; reichstein@rz.rwth-aachen.de NR 12 TC 1 Z9 3 U1 0 U2 0 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0885-7458 J9 INT J PARALLEL PROG JI Int. J. Parallel Program. PD JUN PY 2008 VL 36 IS 3 BP 312 EP 325 DI 10.1007/s10766-008-0074-5 PG 14 WC Computer Science, Theory & Methods SC Computer Science GA 301EG UT WOS:000255878600003 ER PT J AU Grecu, M Olson, WS AF Grecu, Mircea Olson, William S. TI Precipitating snow retrievals from combined airborne cloud radar and millimeter-wave radiometer observations SO JOURNAL OF APPLIED METEOROLOGY AND CLIMATOLOGY LA English DT Article ID PASSIVE MICROWAVE OBSERVATIONS; PROFILING ALGORITHM; BAYESIAN-ESTIMATION; SIZE DISTRIBUTIONS; SIMULATION; MODEL; PARAMETERIZATION; VERIFICATION; TEMPERATURE; SYSTEM AB An algorithm for retrieving snow over oceans from combined cloud radar and millimeter-wave radiometer observations is developed. The algorithm involves the use of physical models to simulate cloud radar and millimeter-wave radiometer observations from basic atmospheric variables such as hydrometeor content, temperature, and relative humidity profiles and is based on an optimal estimation technique to retrieve these variables from actual observations. A high-resolution simulation of a lake-effect snowstorm by a cloud-resolving model is used to test the algorithm. That is, synthetic observations are generated from the output of the cloud numerical model, and the retrieval algorithm is applied to the synthetic data. The algorithm performance is assessed by comparing the retrievals with the reference variables used in synthesizing the observations. The synthetic observation experiment indicates good performance of the retrieval algorithm. The algorithm is also applied to real observations from the Wakasa Bay field experiment that took place over the Sea of Japan in January and February 2003. The application of the retrieval algorithm to data from the field experiment yields snow estimates that are consistent with both the cloud radar and radiometer observations. C1 [Grecu, Mircea; Olson, William S.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Grecu, Mircea] Univ Maryland, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21201 USA. [Olson, William S.] Univ Maryland, Joint Ctr Earth Syst Technol, Baltimore, MD 21201 USA. RP Grecu, M (reprint author), NASA, Goddard Space Flight Ctr, Code 613-1, Greenbelt, MD 20771 USA. EM grecu@agnes.gsfc.nasa.gov NR 35 TC 26 Z9 26 U1 0 U2 4 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 1558-8424 J9 J APPL METEOROL CLIM JI J. Appl. Meteorol. Climatol. PD JUN PY 2008 VL 47 IS 6 BP 1634 EP 1650 DI 10.1175/2007JAMC1728.1 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 327GS UT WOS:000257718200006 ER PT J AU Davis, MW Stephenson, J Noga, EJ AF Davis, Michael W. Stephenson, Jeana Noga, Edward J. TI The effect of tricaine on use of the fluorescein test for detecting skin and corneal ulcers in fish SO JOURNAL OF AQUATIC ANIMAL HEALTH LA English DT Article ID ULCERATION RESPONSE AUR; STRIPED BASS; BROOK TROUT; MORTALITY; ACID; CELL; PH; ANESTHETICS; LIDOCAINE; ALUMINUM AB Fluorescein has been used for rapid and sensitive detection of fish skin and corneal ulceration. Effective use of the fluorescein test requires knowledge of conditions that might cause misleading interpretations or otherwise interfere with test reliability. Examination of fish health and the clinical workup often require tricaine as one of the most commonly used anesthetics. However, tricaine may interfere with correct interpretation of the fluorescein test and might also cause significant fish injury. The effects of tricaine exposure sequence on the fidelity of the fluorescein test was studied in Pacific halibut Hippoglossus stenolepis, walleye pollock Theragra chalcogramma, and northern rock soles Lepidopsetta polyxystra by examining the fluorescence of experimentally induced epidermal wounding. Tricaine can quench fluorescence that is emitted by fluorescein retained in skin ulcers, causing a false-negative reaction. Thus, for the fluorescein test to work properly, it is important to avoid the exposure of fluorescein-treated and rinsed ulcers to tricaine. The effects of exposure to buffered versus unbuffered tricaine on epidermal and corneal integrity were studied in Nile tilapia Oreochromis niloticus and channel catfish Ictalurus punctatus subjected to the fluorescein test and histological examination. Fluorescein could detect not only ulcers but also areas with only a partial loss of epithelium (i.e., erosion). The use of unbuffered tricaine to anesthetize these fish caused serious epidermal and corneal damage. If fish are euthanized with unbuffered tricaine for clinical workup, this severe epidermal or corneal damage could be misinterpreted as an antemortem lesion, leading to misdiagnosis. Even in water with alkalinity exceeding 50 mg/L as CaCO3, it would seem prudent to always buffer tricaine with sodium bicarbonate to prevent a pH change that might lead to iatrogenic effects from unbuffered tricaine. Thus, current general recommendations suggesting that tricaine does not need to be buffered in waters with alkalinity greater than 50 mg/L might need to be modified. C1 [Stephenson, Jeana; Noga, Edward J.] N Carolina State Univ, Coll Vet Med, Dept Clin Sci, Raleigh, NC 27607 USA. [Davis, Michael W.] Hatfield Marine Sci Ctr, Alaska Fisheries Sci Ctr, Natl Marine Fisheries Serv, Natl Ocean & Atmospher Adm, Newport, OR 97365 USA. RP Noga, EJ (reprint author), N Carolina State Univ, Coll Vet Med, Dept Clin Sci, 4700 Hillsborough St, Raleigh, NC 27607 USA. EM ed_noga@ncsu.edu NR 22 TC 5 Z9 6 U1 0 U2 9 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 USA SN 0899-7659 J9 J AQUAT ANIM HEALTH JI J. Aquat. Anim. Health PD JUN PY 2008 VL 20 IS 2 BP 86 EP 95 DI 10.1577/H07-023.1 PG 10 WC Fisheries; Veterinary Sciences SC Fisheries; Veterinary Sciences GA 333PW UT WOS:000258165600002 PM 18783129 ER PT J AU Wang, H Pinker, RT Minnis, P Khaiyer, MM AF Wang, H. Pinker, R. T. Minnis, P. Khaiyer, M. M. TI Experiments with cloud properties: Impact on surface radiative fluxes SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID GENERAL-CIRCULATION MODEL; SOLAR IRRADIANCE; ATMOSPHERIC HYDROLOGY; BUDGET; CLIMATE; ALGORITHMS; AEROSOL; COLUMN; SCALE; MODIS AB Solar radiation reaching the earth's surface provides the primary forcing of the climate system, and thus, information on this parameter is needed at a global scale. Several satellite-based estimates of surface radiative fluxes are available, but they differ from each other in many aspects. The focus of this study is to highlight one aspect of such differences, namely, the way satellite-observed radiances are used to derive information on cloud optical properties and the impact this has on derived parameters such as surface radiative fluxes. Frequently, satellite visible radiance in a single channel is used to infer cloud transmission; at times, several spectral channels are utilized to derive cloud optical properties and use these to infer cloud transmission. In this study, an evaluation of these two approaches will be performed in terms of impact on the accuracy in surface radiative fluxes. The University of Maryland Satellite Radiation Budget (UMD/SRB) model is used as a tool to perform such an evaluation over the central United States. The estimated shortwave fluxes are evaluated against ground observations at the Atmospheric Radiation Measurement Program (ARM) Central Facility and at four ARM extended sites. It is shown that the largest differences between these two approaches occur during the winter season when snow is on the ground. C1 [Wang, H.; Pinker, R. T.] Univ Maryland, Dept Atmospher & Ocean Sci, College Pk, MD 20742 USA. [Minnis, P.] NASA, Langley Res Ctr, Hampton, VA 23665 USA. [Khaiyer, M. M.] Sci Syst & Applicat Inc, Hampton, VA USA. RP Pinker, RT (reprint author), Univ Maryland, Dept Atmospher & Ocean Sci, Coll Pk, College Pk, MD 20742 USA. EM pinker@atmos.umd.edu RI Pinker, Rachel/F-6565-2010; Minnis, Patrick/G-1902-2010 OI Minnis, Patrick/0000-0002-4733-6148 NR 33 TC 0 Z9 0 U1 0 U2 3 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0739-0572 J9 J ATMOS OCEAN TECH JI J. Atmos. Ocean. Technol. PD JUN PY 2008 VL 25 IS 6 BP 1034 EP 1040 DI 10.1175/2007JTECHO546.1 PG 7 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA 309NV UT WOS:000256468400014 ER PT J AU Chen, JY Del Genio, AD Carlson, BE Bosilovich, MG AF Chen, Junye Del Genio, Anthony D. Carlson, Barbara E. Bosilovich, Michael G. TI The spatiotemporal structure of twentieth-century climate variations in observations and reanalyses. Part I: Long-term trend SO JOURNAL OF CLIMATE LA English DT Article ID SEA-SURFACE TEMPERATURE; NINO-SOUTHERN-OSCILLATION; EL-NINO; AIR-TEMPERATURE; ATMOSPHERIC BRIDGE; INTERDECADAL VARIABILITY; EXTENDED RECONSTRUCTION; TROPICAL PACIFIC; SULFATE AEROSOLS; GLOBAL ANALYSES AB The dominant interannual El Nino-Southern Oscillation (ENSO) phenomenon and the short length of climate observation records make it difficult to study long-term climate variations in the spatiotemporal domain. Based on the fact that the ENSO signal spreads to remote regions and induces delayed climate variation through atmospheric teleconnections, an ENSO-removal method is developed through which the ENSO signal can be approximately removed at the grid box level from the spatiotemporal field of a climate parameter. After this signal is removed, long-term climate variations are isolated at mid-and low latitudes in the climate parameter fields from observed and reanalysis datasets. This paper addresses the long-term global warming trend (GW); a companion paper concentrates on Pacific pan-decadal variability (PDV). The warming that occurs in the Pacific basin (approximately 0.4 K in the twentieth century) is much weaker than in surrounding regions and the other two ocean basins (approximately 0.8 K). The modest warming in the Pacific basin is likely due to its dynamic nature on the interannual and decadal time scales and/ or the leakage of upper ocean water through the Indonesian Throughflow. Based on the National Centers for Environmental Prediction-National Center for Atmospheric Research (NCEP-NCAR) and the 40-yr European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis (ERA-40), a comprehensive atmospheric structure associated with the GW trend is given. Significant discrepancies exist between the two datasets, especially in the tightly coupled dynamics and water vapor fields. The dynamics fields based on NCEP-NCAR, which show a change in the Walker Circulation, are consistent with the GW change in the surface temperature field. However, intensification in the Hadley Circulation is associated with GW trend in ERA-40 instead. C1 [Chen, Junye; Bosilovich, Michael G.] NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Greenbelt, MD 20771 USA. [Chen, Junye] Univ Maryland, Earth Syst Sci Interdisciplinary Ctr, College Pk, MD 20742 USA. [Del Genio, Anthony D.; Carlson, Barbara E.] NASA, Goddard Inst Space Studies, New York, NY 10025 USA. RP Chen, JY (reprint author), NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Code 610-1, Greenbelt, MD 20771 USA. EM jchen@essic.umd.edu RI Chen, Junye/G-4301-2011; Del Genio, Anthony/D-4663-2012; Carlson, Barbara/D-8319-2012; Bosilovich, Michael/F-8175-2012 OI Del Genio, Anthony/0000-0001-7450-1359; NR 87 TC 37 Z9 41 U1 0 U2 10 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 EI 1520-0442 J9 J CLIMATE JI J. Clim. PD JUN PY 2008 VL 21 IS 11 BP 2611 EP 2633 DI 10.1175/2007JCLI2011.1 PG 23 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 311TL UT WOS:000256623200017 ER PT J AU Chen, JY Del Genio, AD Carlson, BE Bosilovich, MG AF Chen, Junye Del Genio, Anthony D. Carlson, Barbara E. Bosilovich, Michael G. TI The spatiotemporal structure of twentieth-century climate variations in observations and reanalyses. Part II: Pacific pan-decadal variability SO JOURNAL OF CLIMATE LA English DT Article ID SEA-SURFACE TEMPERATURES; NORTH PACIFIC; SOUTHERN-HEMISPHERE; INTERDECADAL VARIABILITY; EXTENDED RECONSTRUCTION; OCEAN; CIRCULATION; DYNAMICS; BASIN; ENSO AB The spatiotemporal structure of Pacific pan-decadal variability (PDV) is isolated in global long-term surface temperature (ST) datasets and reanalysis atmospheric parameter fields from which El Nino Southern Oscillation (ENSO) effects have been removed. Empirical orthogonal function (EOF) and combined EOF analysis of the resulting time series identify PDV as one of two primary modes of long-term variability, the other being a global warming (GW) trend, which is addressed in a companion paper (Part I). In this study, it is shown that one of several PDV interdecadal regime shifts occurred during the 1990s. This significant change in the Pacific basin is comparable but antiphase to the well-known 1976 climate regime shift and is consistent with the observed changes in biosystems and ocean circulation. A comprehensive picture of PDV as manifested in the troposphere and at the surface is described. In general, the PDV spatial patterns in different parameter fields share some similarities with the patterns associated with ENSO, but important differences exist. First, the PDV circulation pattern is shifted westward by about 20 and is less zonally extended than that for ENSO. The westward shift of the PDV wave train produces a different North American teleconnection pattern that is more west-east oriented. The lack of a strong PDV surface temperature (ST) signal in the west equatorial Pacific and the relatively strong ST signal in the subtropical regions are consistent with an atmospheric overturning circulation response that differs from the one associated with ENSO. The analysis also suggests that PDV is a combination of decadal and/or interdecadal oscillations interacting through teleconnections. C1 [Chen, Junye; Bosilovich, Michael G.] NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Greenbelt, MD 20771 USA. [Chen, Junye] Univ Maryland, Earth Syst Sci Interdisciplinary Ctr, College Pk, MD 20742 USA. [Del Genio, Anthony D.; Carlson, Barbara E.] NASA, Goddard Inst Space Studies, New York, NY 10025 USA. RP Chen, JY (reprint author), NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Code 610-1, Greenbelt, MD 20771 USA. EM jchen@essic.umd.edu RI Chen, Junye/G-4301-2011; Del Genio, Anthony/D-4663-2012; Carlson, Barbara/D-8319-2012; Bosilovich, Michael/F-8175-2012 OI Del Genio, Anthony/0000-0001-7450-1359; NR 47 TC 35 Z9 36 U1 1 U2 6 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 EI 1520-0442 J9 J CLIMATE JI J. Clim. PD JUN PY 2008 VL 21 IS 11 BP 2634 EP 2650 DI 10.1175/2007JCLI2012.1 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 311TL UT WOS:000256623200018 ER PT J AU Jiang, XN Lau, NC AF Jiang, Xianan Lau, Ngar-Cheung TI Intraseasonal teleconnection between North American and western North Pacific monsoons with 20-day time scale SO JOURNAL OF CLIMATE LA English DT Article ID OUTGOING LONGWAVE RADIATION; GULF-OF-CALIFORNIA; INTERANNUAL VARIABILITY; UNITED-STATES; SUMMER PRECIPITATION; MEXICAN MONSOON; EAST-ASIA; SURGES; OSCILLATION; CIRCULATION AB Based on a recently released, high-resolution reanalysis dataset for the North American region, the intraseasonal variability (ISV; with a time scale of about 20 days) of the North American monsoon (NAM) is examined. The rainfall signals associated with this phenomenon first emerge near the Gulf of Mexico and eastern Pacific at about 20 degrees N. They subsequently migrate to the southwestern United States along the slope of the Sierra Madre Occidental. The rainfall quickly dissipates upon arrival at the desert region of Arizona and New Mexico (AZNM). The enhanced rainfall over AZNM is accompanied by strong southeasterly low-level flow along the Gulf of California. This pattern bears strong resemblance to the circulation related to "gulf surge" events, as documented by many studies. The southeasterly flow is associated with an anomalous low vortex over the subtropical eastern Pacific Ocean off California, and a midlatitude anticyclone over the central United States in the lower troposphere. This flow pattern is in broad agreement with that favoring the "wet surges" over the southwestern United States. It is further demonstrated that the aforementioned low-level circulations associated with ISV of the NAM are part of a prominent trans-Pacific wave train extending from the western North Pacific (WNP) to the Eastern Pacific/North America along a "great circle" path. The circulation anomalies along the axis of this wave train exhibit a barotropic vertical structure over most regions outside of the WNP, and a baroclinic structure over the WNP, thus suggesting the important role of convective activities over the WNP in sustaining this wave train. This inference is further substantiated by an analysis of the pattern of waveactivity -flux vectors. Variations in the WNP convection are correlated with the ISV of the monsoons in both North American and East Asian (EA)/WNP sectors. These relationships lead to notable teleconnections between NAM and the EA/WNP monsoon on 20-day time scales. C1 [Jiang, Xianan] Princeton Univ, Atmospher & Ocean Sci Program, Princeton, NJ 08544 USA. [Lau, Ngar-Cheung] Princeton Univ, NOAA, Geophys Fluid Dynam Lab, Princeton, NJ 08544 USA. RP Jiang, XN (reprint author), CALTECH, Jet Prop Lab, MS 183-501,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM xianan@caltech.edu RI Jiang, Xianan/A-2283-2012 NR 45 TC 24 Z9 27 U1 1 U2 7 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 EI 1520-0442 J9 J CLIMATE JI J. Clim. PD JUN PY 2008 VL 21 IS 11 BP 2664 EP 2679 DI 10.1175/2007JCLI2024.1 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 311TL UT WOS:000256623200020 ER PT J AU Zaitchik, BF Rodell, M Reichle, RH AF Zaitchik, Benjamin F. Rodell, Matthew Reichle, Rolf H. TI Assimilation of GRACE terrestrial water storage data into a Land Surface Model: Results for the Mississippi River basin SO JOURNAL OF HYDROMETEOROLOGY LA English DT Article ID ENSEMBLE KALMAN FILTER; SOIL-MOISTURE; SNOW COVER; PRECIPITATION; SYSTEM; SIMULATION; SMOOTHER; RECOVERY; PHYSICS; FIELDS AB Assimilation of data from the Gravity Recovery and Climate Experiment (GRACE) system of satellites yielded improved simulation of water storage and fluxes in the Mississippi River basin, as evaluated against independent measurements. The authors assimilated GRACE-derived monthly terrestrial water storage (TWS) anomalies for each of the four major subbasins of the Mississippi into the Catchment Land Surface Model (CLSM) using an ensemble Kalman smoother from January 2003 to May 2006. Compared with the open-loop CLSM simulation, assimilation estimates of groundwater variability exhibited enhanced skill with respect to measured groundwater in all four subbasins. Assimilation also significantly increased the correlation between simulated TWS and gauged river flow for all four subbasins and for the Mississippi River itself. In addition, model performance was evaluated for eight smaller watersheds within the Mississippi basin, all of which are smaller than the scale of GRACE observations. In seven of eight cases, GRACE assimilation led to increased correlation between TWS estimates and gauged river flow, indicating that data assimilation has considerable potential to downscale GRACE data for hydrological applications. C1 [Zaitchik, Benjamin F.; Rodell, Matthew] NASA, Goddard Space Flight Ctr, Hydrol Sci Branch, Greenbelt, MD 20771 USA. [Zaitchik, Benjamin F.] Univ Maryland, Earth System Sci Interdisciplinary Ctr, College Pk, MD 20742 USA. [Reichle, Rolf H.] Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD USA. [Reichle, Rolf H.] NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Greenbelt, MD 20771 USA. RP Zaitchik, BF (reprint author), NASA, Goddard Space Flight Ctr, Hydrol Sci Branch, Code 614-3, Greenbelt, MD 20771 USA. EM ben.zaitchik@nasa.gov RI Reichle, Rolf/E-1419-2012; Rodell, Matthew/E-4946-2012; Zaitchik, Benjamin/B-9461-2013 OI Rodell, Matthew/0000-0003-0106-7437; NR 46 TC 107 Z9 111 U1 4 U2 35 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 1525-755X EI 1525-7541 J9 J HYDROMETEOROL JI J. Hydrometeorol. PD JUN PY 2008 VL 9 IS 3 BP 535 EP 548 DI 10.1175/2007JHM951.1 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 316QY UT WOS:000256966000014 ER PT J AU Hossain, F Huffman, GJ AF Hossain, Faisal Huffman, George J. TI Investigating error metrics for satellite rainfall data at hydrologically relevant scales SO JOURNAL OF HYDROMETEOROLOGY LA English DT Article ID GLOBAL PRECIPITATION; UNCERTAINTY; RESOLUTION; BIASES; TRMM AB This paper addresses the following open question: What set of error metrics for satellite rainfall data can advance the hydrologic application of new-generation, high-resolution rainfall products over land? The authors' primary aim is to initiate a framework for building metrics that are mutually interpretable by hydrologists (users) and algorithm developers (data producers) and to provide more insightful information on the quality of the satellite estimates. In addition, hydrologists can use the framework to develop a space-time error model for simulating stochastic realizations of satellite estimates for quantification of the implication on hydrologic simulation uncertainty. First, the authors conceptualize the error metrics in three general dimensions: 1) spatial (how does the error vary in space?); 2) retrieval (how "off" is each rainfall estimate from the true value over rainy areas?); and 3) temporal (how does the error vary in time?). They suggest formulations for error metrics specific to each dimension, in addition to ones that are already widely used by the community. They then investigate the behavior of these metrics as a function of spatial scale ranging from 0.04 degrees to 1.0 degrees for the Precipitation Estimation from Remotely Sensed Information Using Artificial Neural Networks (PERSIANN) geostationary infrared-based algorithm. It is observed that moving to finer space-time scales for satellite rainfall estimation requires explicitly probabilistic measures that are mathematically amenable to space-time stochastic simulation of satellite rainfall data. The probability of detection of rain as a function of ground validation rainfall magnitude is found to be most sensitive to scale followed by the correlation length for detection of rain. Conventional metrics such as the correlation coefficient, frequency bias, false alarm ratio, and equitable threat score are found to be modestly sensitive to scales smaller than 0.24 latitude/longitude. Error metrics that account for an algorithm's ability to capture rainfall intermittency as a function of space appear useful in identifying the useful spatial scales of application for the hydrologist. It is shown that metrics evolving from the proposed conceptual framework can identify seasonal and regional differences in reliability of four global satellite rainfall products over the United States more clearly than conventional metrics. The proposed framework for building such error metrics can lay a foundation for better interaction between the data-producing community and hydrologists in shaping the new generation of satellite-based, high-resolution rainfall products, including those being developed for the planned Global Precipitation Measurement (GPM) mission. C1 [Hossain, Faisal] Tennessee Technol Univ, Dept Civil & Environm Engn, Cookeville, TN 38505 USA. [Huffman, George J.] NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. [Huffman, George J.] Sci Syst & Applicat Inc, Greenbelt, MD USA. RP Hossain, F (reprint author), Tennessee Technol Univ, Dept Civil & Environm Engn, 1020 Stadium Dr, Cookeville, TN 38505 USA. EM fhossain@tntech.edu RI Huffman, George/F-4494-2014 OI Huffman, George/0000-0003-3858-8308 NR 35 TC 72 Z9 75 U1 2 U2 19 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 1525-755X EI 1525-7541 J9 J HYDROMETEOROL JI J. Hydrometeorol. PD JUN PY 2008 VL 9 IS 3 BP 563 EP 575 DI 10.1175/2007JHM925.1 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 316QY UT WOS:000256966000016 ER PT J AU Baty, RS Farassat, F Tucker, DH AF Baty, Roy S. Farassat, F. Tucker, Don H. TI Nonstandard analysis and jump conditions for converging shock waves SO JOURNAL OF MATHEMATICAL PHYSICS LA English DT Article ID DISTRIBUTIONS; MULTIPLICATIONS; AMBIGUITIES AB Nonstandard analysis is an area of modern mathematics that studies abstract number systems containing both infinitesimal and infinite numbers. This article applies nonstandard analysis to derive jump conditions for one-dimensional, converging shock waves in a compressible, inviscid, perfect gas. It is assumed that the shock thickness occurs on an infinitesimal interval and the jump functions in the thermodynamic and fluid dynamic parameters occur smoothly across this interval. Predistributions of the Heaviside function and the Dirac delta measure are introduced to model the flow parameters across a shock wave. The equations of motion expressed in nonconservative form are then applied to derive unambiguous relationships between the jump functions for the flow parameters. (c) 2008 American Institute of Physics. C1 [Baty, Roy S.] Los Alamos Natl Lab, Los Alamos, NM 87545 USA. [Farassat, F.] NASA Langley Res Ctr, Hampton, VA 23681 USA. [Tucker, Don H.] Univ Utah, Salt Lake City, UT 84112 USA. RP Baty, RS (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 27 TC 5 Z9 5 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0022-2488 J9 J MATH PHYS JI J. Math. Phys. PD JUN PY 2008 VL 49 IS 6 AR 063101 DI 10.1063/1.2939482 PG 18 WC Physics, Mathematical SC Physics GA 321DH UT WOS:000257284400017 ER PT J AU Cohrs, RJ Mehta, SK Schmid, DS Gilden, DH Pierson, DL AF Cohrs, Randall J. Mehta, Satish K. Schmid, D. Scott Gilden, Donald H. Pierson, Duane L. TI Asymptomatic reactivation and shed of infectious varicella zoster virus in astronauts SO JOURNAL OF MEDICAL VIROLOGY LA English DT Article DE varicella zoster virus (VZV); human; histochemistry; sub-clinical; reactivation ID HERPES-SIMPLEX-VIRUS; POLYMERASE-CHAIN-REACTION; EPSTEIN-BARR-VIRUS; GENITAL HERPES; SPACE-FLIGHT; HSV-1 DNA; SPACEFLIGHT; TYPE-1; SALIVA; GANGLIA AB Varicella zoster virus (VZV) causes varicella (chickenpox), after which virus becomes latent in ganglia along the entire neuraxis. Virus reactivation produces zoster (shingles). Infectious VZV is found in vesicles of patients with zoster and varicella, but virus shed in the absence of disease has not been documented. VZV DNA was previously detected in saliva of astronauts during and after spaceflight, a uniquely stressful environment in which cell mediated immunity (CMI) is temporally dampened. The decline in CMI to VZV associated with zoster led to the hypothesis that infectious VZV would also be present in the saliva of astronauts subjected to stress of spaceflight. Herein, not only was the detection of salivary VZV DNA associated with spaceflight validated, but also infectious virus was detected in saliva from 2 of 3 astronauts. This is the first demonstration of shed of infectious VZV in the absence of disease. C1 [Cohrs, Randall J.; Gilden, Donald H.] Univ Colorado, Sch Med, Dept Neurol, Denver, CO 80262 USA. [Mehta, Satish K.] Enterprise Advisory Serv Inc, Houston, TX USA. [Schmid, D. Scott] CDC, Natl VZV Lab, Atlanta, GA 30333 USA. [Gilden, Donald H.] Univ Colorado, Sch Med, Dept Microbiol, Denver, CO 80262 USA. [Pierson, Duane L.] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Cohrs, RJ (reprint author), Univ Colorado, Sch Med, Dept Neurol, Mail Stop B182,4200 E 9th Ave,SOM 3657, Denver, CO 80262 USA. EM randall.cohrs@uchsc.edu FU NIA NIH HHS [AG06127, R01 AG006127, R37 AG006127, R37 AG006127-16]; NINDS NIH HHS [P01 NS032623, NS32623, P01 NS032623-18] NR 30 TC 63 Z9 67 U1 0 U2 6 PU WILEY-LISS PI HOBOKEN PA DIV JOHN WILEY & SONS INC, 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0146-6615 J9 J MED VIROL JI J. Med. Virol. PD JUN PY 2008 VL 80 IS 6 BP 1116 EP 1122 DI 10.1002/jmv.21173 PG 7 WC Virology SC Virology GA 293AP UT WOS:000255307500028 PM 18428120 ER PT J AU Garg, RK Kim, SS Hash, DB Gore, JP Fisher, IS AF Garg, R. K. Kim, S. S. Hash, D. B. Gore, J. P. Fisher, I. S. TI Effects of feed gas composition and catalyst thickness on carbon nanotube and nanofiber synthesis by plasma enhanced chemical vapor deposition SO JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY LA English DT Article DE carbon nanotubes; carbon nanofibers; plasma enhanced chemical vapor deposition; reaction mechanisms ID FIELD-EMISSION DISPLAY; GROWTH; DECOMPOSITION; ACETYLENE; DENSITY; REACTOR; TEMPERATURE; FABRICATION; CHEMISTRY; BIOSENSOR AB Many engineering applications require carbon nanotubes with specific characteristics such as wall structure, chirality and alignment. However, precise control of nanotube properties grown to application specifications remains a significant challenge. Plasma-enhanced chemical vapor deposition (PECVD) offers a variety of advantages in the synthesis of carbon nanotubes in that several important synthesis parameters can be controlled independently. This paper reports an experimental study of the effects of reacting gas composition (percentage methane in hydrogen) and catalyst film thickness on carbon nanotube (CNT) growth and a computational study of gas-phase composition for the inlet conditions of experimentally observed carbon nanotube growth using different chemical reaction mechanisms. The simulations seek to explain the observed effects of reacting gas composition and to identify the precursors for CNT formation. The experimental results indicate that gas-phase composition significantly affects the synthesized material, which is shown to be randomly aligned nanotube and nanofiber mats for relatively methane-rich inlet gas mixtures and non-tubular carbon for methane-lean incoming mixtures. The simulation results suggest that inlet methane-hydrogen mixture coverts to an acetylene-methane-hydrogen mixture with minor amounts of ethylene, hydrogen atom, and methyl radical. Acetylene appears to be the indicator species for solid carbon formation. The simulations also show that inlet methane-hydrogen mixture does not produce enough gas-phase precursors needed to form quality CNTs below 5% CH4 concentrations in the inlet stream. C1 [Garg, R. K.; Kim, S. S.; Gore, J. P.; Fisher, I. S.] Purdue Univ, Sch Mech Engn, W Lafayette, IN 47907 USA. [Garg, R. K.; Kim, S. S.; Gore, J. P.; Fisher, I. S.] Purdue Univ, Birck Nanotechnol Ctr, W Lafayette, IN 47907 USA. [Hash, D. B.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Fisher, IS (reprint author), Purdue Univ, Sch Mech Engn, W Lafayette, IN 47907 USA. NR 40 TC 13 Z9 13 U1 2 U2 13 PU AMER SCIENTIFIC PUBLISHERS PI VALENCIA PA 26650 THE OLD RD, STE 208, VALENCIA, CA 91381-0751 USA SN 1533-4880 J9 J NANOSCI NANOTECHNO JI J. Nanosci. Nanotechnol. PD JUN PY 2008 VL 8 IS 6 BP 3068 EP 3076 DI 10.1166/jnn.2008.082 PG 9 WC Chemistry, Multidisciplinary; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 320YR UT WOS:000257271600038 PM 18681048 ER PT J AU Moisan, TA Swift, RN Campbell, BA Yungel, JK Linkswiler, MA Nolan, JK AF Moisan, Tiffany A. Swift, Robert N. Campbell, Brian A. Yungel, James K. Linkswiler, Matthew A. Nolan, Jessica K. TI A Practical Application of Ocean Color Methodology to an Undergraduate Curriculum SO JOURNAL OF SCIENCE EDUCATION AND TECHNOLOGY LA English DT Article DE Radiometer; Oceanography; Remote sensing; Satellites; Science education technology AB Recently there have been newly launched ocean color satellites which target the coastlines at unprecedented scales. Science education curricula can benefit from the provision of small low-cost spectroradiometers and curriculum supplemental materials that can be incorporated in a "hands on'' teaching approach to explain and demonstrate remote sensing reflectance principles. A lesson in which a progressive set of spectral measurements of familiar and unfamiliar objects and natural waters acquired by students using a small fiberoptic probe and spectroradiometer is presented. This lesson has a dual purpose. The first is to serve as a teaching supplement to high school science curricula while paralleling the National Science Education Standards (NSES) for NASA ocean color products, as well as other satellite ocean products such as GLI and MERIS. The second is to focus on the scientific goals of the graduate-school bound undergraduate student by providing a fundamental understanding of the principles of passive ocean color remote sensing that will perhaps nurture the interest of some students toward research involving utilization of NASA's Earth science data products. We intend to have these spectroradiometers readily available for use by teachers in the Earth sciences through a publicly available technology library. C1 [Campbell, Brian A.] NASA, Goddard Space Flight Ctr, SAIC, Greenbelt, MD 20771 USA. [Moisan, Tiffany A.] NASA, Goddard Space Flight Ctr, Hydrospher & Biospher Sci Lab, Wallops Isl, VA 23337 USA. [Swift, Robert N.; Yungel, James K.; Linkswiler, Matthew A.] NASA, Wallops Flight Facil, EG&G Tech Serv, Wallops Isl, VA 23337 USA. [Nolan, Jessica K.] York Coll Penn, Dept Biol, York, PA 17405 USA. RP Campbell, BA (reprint author), NASA, Goddard Space Flight Ctr, SAIC, Greenbelt, MD 20771 USA. EM Brian.A.Campbell@nasa.gov NR 14 TC 0 Z9 0 U1 0 U2 4 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1059-0145 J9 J SCI EDUC TECHNOL JI J. Sci. Educ. Technol. PD JUN PY 2008 VL 17 IS 3 BP 252 EP 261 DI 10.1007/s10956-008-9095-5 PG 10 WC Education & Educational Research; Education, Scientific Disciplines SC Education & Educational Research GA 498KP UT WOS:000270139200007 ER PT J AU Miranda, FA Mueller, CH Van Keuls, FW Romanofsky, RR AF Miranda, Felix A. Mueller, Carl H. Van Keuls, Frederick W. Romanofsky, Robert R. TI Ba(x)Sr(1-x)TiO(3) thin film ferroelectric-coupled microstripline phase shifters with reduced device hysteresis SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID FREQUENCY-AGILE; VARACTORS; SYSTEMS AB In this work, we present experimental results on the performance of coupled microstriptine phase shifters (CMPS) fabricated using Ba(x)Sr(1-x)TiO(3) (BST) ferroelectric thin films. The CMPS were fabricated using commercially available pulsed laser deposition BST films with Ba:Sr ratios of 30:70 and 20:80. Microwave characterization of these CMPS was performed at upper Ku-band frequencies, particularly at frequencies near 16 and 18 GHz. The quality of performance of the CMPS was studied based on their relative phase shift (Delta phi = phi(n)v-phi(0)v, where n = 0-400 V DC) and insertion loss within the DC bias range of 0-400 V (i.e., E-field ranges within 0-53 V/mu m). The performance of the CMPS was tested as a function of temperature to investigate their operation in the paraelectric as well as in the ferroelectric state (i.e., above and below the Curie temperature, respectively). It was observed that for the CMPS fabricated with the BST films, with Ba:Sr ratio of 30:70, the performance was very good with A(p up to 400 degrees and nominal insertion losses of similar to 3 dB. In addition, these devices were hysteresis-free in the paraelectric state and only showed A(p hysteresis while performing in the ferroelectric state. In contrast, while the CMPS made with Ba:Sr ratios of 20:80 exhibited very good values of A(p, they exhibited a mild hysteresis both in the paraelectric and ferroelectric states. X-ray diffraction studies indicate that the 30:70 films exhibit almost a 1:1 ratio between the in-plane and out-of-plane lattice parameters, suggesting that their cubic structure creates strain-free films conducive to CMPS devices with reduced hysteresis in the paraelectric state. Elimination of A(p hysteresis is essential because many practical microwave applications such as voltage-controlled oscillators and beam steerable devices, particularly electronically steerable phased array antennas, rely on accurate phase shift versus tuning voltage profiles required for reliable device operation. Accordingly, the optimization of the interplay between film microstructure, Ba content, and dielectric constant is critical for reliable CMPS devices. C1 [Miranda, Felix A.; Romanofsky, Robert R.] NASA Glenn Res Ctr, Cleveland, OH 44135 USA. [Mueller, Carl H.] Analex Corp, Brookpark, OH 44142 USA. [Van Keuls, Frederick W.] Ohio Aerosp Inst, Brookpark, OH 44142 USA. RP Miranda, FA (reprint author), NASA Glenn Res Ctr, Cleveland, OH 44135 USA. EM Felix.A.Miranda@nasa.gov NR 13 TC 11 Z9 11 U1 1 U2 5 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD JUN PY 2008 VL 91 IS 6 BP 1864 EP 1868 DI 10.1111/j.1551-2916.2007.02235.x PG 5 WC Materials Science, Ceramics SC Materials Science GA 308SQ UT WOS:000256410700018 ER PT J AU Shi, T Yu, B Clothiaux, EE Braverman, AJ AF Shi, Tao Yu, Bin Clothiaux, Eugene E. Braverman, Amy J. TI Daytime Arctic cloud detection based on multi-angle satellite data with case studies SO JOURNAL OF THE AMERICAN STATISTICAL ASSOCIATION LA English DT Article DE classification; clustering; feature selection; Multiangle Imaging SpectroRadiometer; quadratic discriminate analysis; remote sensing ID MISR AB Global climate models predict that the strongest dependences of surface air temperatures on increasing atmospheric carbon dioxide levels will occur in the Arctic. A systematic study of these dependences requires accurate Arctic-wide measurements, especially of cloud coverage. Thus cloud detection in the Arctic is extremely important, but it is also challenging because of the similar remote sensing characteristics of clouds and ice- and snow-covered surfaces. This article proposes two new operational Arctic cloud detection algorithms using Multiangle Imaging SpectroRadiometer (MISR) imagery. The key idea is to identify cloud-free surface pixels in the imagery instead of cloudy pixels as in the existing MISR operational algorithms. Through extensive exploratory data analysis and using domain knowledge, three physically useful features to differentiate surface pixels from cloudy pixels have been identified. The first algorithm, enhanced linear correlation matching (ELCM), thresholds the features with either fixed or data-adaptive cutoff values. Probability labels are obtained by using ELCM labels as training data for Fisher's quadratic discriminant analysis (QDA), leading to the second (ELCM-QDA) algorithm. Both algorithms are automated and computationally efficient for operational processing of the massive MISR data set. Based on 5 million expert-labeled pixels, ELCM results are significantly in terms of both accuracy (92%) and coverage (100%) compared with two MISR operational algorithms, one with an accuracy of 80% and coverage of 27% and the other with an accuracy of 83% and a coverage of 70%. The ELCM-QDA probability prediction is also consistent with the expert labels and is more informative. In conclusion, ELCM and ELCM-QDA provide the best performance to date among all available operational algorithms using MISR data. C1 [Shi, Tao] Ohio State Univ, Dept Stat, Columbus, OH 43210 USA. [Yu, Bin] Univ Calif Berkeley, Dept Stat, Berkeley, CA 94720 USA. [Clothiaux, Eugene E.] Penn State Univ, Dept Meteorol, University Pk, PA 16802 USA. [Braverman, Amy J.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Shi, T (reprint author), Ohio State Univ, Dept Stat, Columbus, OH 43210 USA. EM taoshi@stat.osu.edu; binyu@stat.berkeley.edu; cloth@essc.psu.edu; Amy.Braverman@jpl.nasa.gov NR 21 TC 3 Z9 3 U1 0 U2 3 PU AMER STATISTICAL ASSOC PI ALEXANDRIA PA 732 N WASHINGTON ST, ALEXANDRIA, VA 22314-1943 USA SN 0162-1459 EI 1537-274X J9 J AM STAT ASSOC JI J. Am. Stat. Assoc. PD JUN PY 2008 VL 103 IS 482 BP 584 EP 593 DI 10.1198/016214507000001283 PG 10 WC Statistics & Probability SC Mathematics GA 329VA UT WOS:000257897500016 ER PT J AU Eitzen, ZA Xu, KM AF Eitzen, Zachary A. Xu, Kuan-Man TI Sensitivity of a large ensemble of tropical convective systems to changes in the thermodynamic and dynamic forcings SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID SEA-SURFACE TEMPERATURE; CLOUD OBJECT DATA; NONHYDROSTATIC ATMOSPHERIC SIMULATION; 1998 EL-NINO; STATISTICAL-ANALYSES; RESOLVING MODEL; PART I; EQUILIBRIUM STATES; FEEDBACK PROCESSES; RADIATION BUDGET AB A two-dimensional cloud-resolving model ( CRM) is used to perform five sets of simulations of 68 deep convective cloud objects identified with Clouds and the Earth's Radiant Energy System (CERES) data to examine their sensitivity to changes in thermodynamic and dynamic forcings. The control set of simulations uses observed sea surface temperatures (SSTs) and is forced by advective cooling and moistening tendencies derived from a large-scale model analysis matched to the time and location of each cloud object. Cloud properties, such as albedo, effective cloud height, cloud ice and snow path, and cloud radiative forcing (CRF), are analyzed in terms of their frequency distributions rather than their mean values. Two sets of simulations, F + 50% and F + 50%, use advective tendencies that are 50% greater and 50% smaller than the control tendencies, respectively. The increased cooling and moistening tendencies cause more widespread convection in the F + 50% set of simulations, resulting in clouds that are optically thicker and higher than those produced by the control and F + 50% sets of simulations. The magnitudes of both longwave and shortwave CRF are skewed toward higher values with the increase in advective forcing. These significant changes in overall cloud properties are associated with a substantial increase in deep convective cloud fraction ( from 0.13 for the F - 50% simulations to 0.34 for the F + 50% simulations) and changes in the properties of non - deep convective clouds, rather than with changes in the properties of deep convective clouds. Two other sets of simulations, SST + 2K and SST + 2K, use SSTs that are 2 K higher and 2 K lower than those observed, respectively. The updrafts in the SST + 2K simulations tend to be slightly stronger than those of the control and SST - 2K simulations, which may cause the SST + 2K cloud tops to be higher. The changes in cloud properties, though smaller than those due to changes in the dynamic forcings, occur in both deep convective and non - deep convective cloud categories. The overall changes in some cloud properties are moderately significant when the SST is changed by 4 K. The changes in the domain-averaged shortwave and longwave CRFs are larger in the dynamic forcing sensitivity sets than in the SST sensitivity sets. The cloud feedback effects estimated from the SST - 2K and SST + 2K sets are comparable to prior studies. C1 [Eitzen, Zachary A.; Xu, Kuan-Man] NASA, Langley Res Ctr, Climate Sci Branch, Hampton, VA 23681 USA. [Eitzen, Zachary A.] Sci Syst & Applicat Inc, Hampton, VA USA. RP Eitzen, ZA (reprint author), NASA, Langley Res Ctr, Climate Sci Branch, Mail Stop 420, Hampton, VA 23681 USA. EM zachary.a.eitzen@nasa.gov RI Xu, Kuan-Man/B-7557-2013 OI Xu, Kuan-Man/0000-0001-7851-2629 NR 50 TC 5 Z9 5 U1 0 U2 2 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-4928 J9 J ATMOS SCI JI J. Atmos. Sci. PD JUN PY 2008 VL 65 IS 6 BP 1773 EP 1794 DI 10.1175/2007JAS2446.1 PG 22 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 310OX UT WOS:000256540000003 ER PT J AU Xian, P Miller, RL AF Xian, Peng Miller, Ron L. TI Abrupt seasonal migration of the ITCZ into the summer hemisphere SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID HADLEY CIRCULATION; GAUGE OBSERVATIONS; DATA SETS; ATMOSPHERE; MODEL; REANALYSIS; SURFACE; EQUILIBRIUM; TRANSPORTS; DYNAMICS AB Although the maximum of solar radiation at the top of the atmosphere moves gradually from one hemisphere to the other as part of the seasonal cycle, the intertropical convergence zone (ITCZ) moves abruptly into the summer hemisphere. An axisymmetric circulation model is developed to study this rapid transition. The model consists of an upper and lower layer of the Hadley circulation (HC), with the surface layer attached to a slab ocean and the lower layer connected to the upper layer by a constant lapse rate. The model is forced by solar heating, and the ITCZ is prescribed to coincide with the warmest sea surface temperature (SST). The collocation of tropical rainfall with warm SST allows the model ITCZ migration to be understood in terms of the relative influence of solar heating and atmospheric dynamics upon ocean temperature. Atmospheric dynamics allow the ITCZ to move off the equator by flattening the meridional temperature gradient that would exist in radiative - convective equilibrium. For the present-day tropical oceanic mixed layer depth and ITCZ width, the model exhibits an abrupt seasonal transition of the ITCZ across the equator. It is found that there are two determinative factors on the abrupt transition of the ITCZ: the nonlinear meridional advection of angular momentum by the circulation and ocean thermal inertia. As a result of nonlinear dynamics, angular momentum is well mixed, resulting in minimum atmospheric temperature at the equator and a similar equatorial minimum in SST. This inhibits convection over the equator while favoring a rapid seasonal transition of the ITCZ between the warmer surface water on either side of this latitude. C1 [Xian, Peng] Columbia Univ, Dept Earth & Environm Sci, New York, NY 10025 USA. [Xian, Peng; Miller, Ron L.] NASA, Goddard Inst Space Studies, New York, NY 10025 USA. [Miller, Ron L.] Columbia Univ, Dept Appl Phys & Appl Math, New York, NY 10025 USA. RP Xian, P (reprint author), Columbia Univ, Dept Earth & Environm Sci, New York, NY 10025 USA. EM px2001@columbia.edu RI Miller, Ron/E-1902-2012 NR 38 TC 9 Z9 9 U1 0 U2 2 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-4928 EI 1520-0469 J9 J ATMOS SCI JI J. Atmos. Sci. PD JUN PY 2008 VL 65 IS 6 BP 1878 EP 1895 DI 10.1175/2007JAS2367.1 PG 18 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 310OX UT WOS:000256540000008 ER PT J AU Conway, EM AF Conway, Erik M. TI The Humboldt current: Nineteenth-century exploration and the roots of American environmentalism SO JOURNAL OF THE HISTORY OF BIOLOGY LA English DT Book Review C1 [Conway, Erik M.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Conway, EM (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0022-5010 J9 J HIST BIOL JI J. Hist. Biol. PD SUM PY 2008 VL 41 IS 2 BP 398 EP 400 PG 3 WC Biology; History & Philosophy Of Science SC Life Sciences & Biomedicine - Other Topics; History & Philosophy of Science GA 302GM UT WOS:000255956800010 ER PT J AU Piredda, G Smith, DD Wendling, B Boyd, RW AF Piredda, Giovanni Smith, David D. Wendling, Bettina Boyd, Robert W. TI Nonlinear optical properties of a gold-silica composite with high gold fill fraction and the sign change of its nonlinear absorption coefficient SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID PERCOLATION-THRESHOLD; SUSCEPTIBILITY; CONDUCTIVITY; FEMTOSECOND; COLLOIDS; MEDIA; FIELD AB We study the intensity-dependent absorption coefficient of gold-silica composites as a function of fill fraction at frequencies near the plasmon resonance. The samples we have studied act as saturable absorbers at all wavelengths and all fill fractions, whereas pure gold is an optical limiter. We provide an explanation based on the intensity-dependent damping of the surface plasmon for this reversal of the sign of the nonlinear absorption. (C) 2008 Optical Society of America. C1 [Piredda, Giovanni; Boyd, Robert W.] Univ Rochester, Inst Opt, Rochester, NY 14627 USA. [Smith, David D.] NASA, George C Marshall Space Flight Ctr, Spacecraft Vehicle Syst Dept, Huntsville, AL 35812 USA. [Wendling, Bettina] Robert Bosch GmbH, Gasoline Syst Sensors & Ignit Business Unit, Exhaust Gas Sensors Engn GS SI ENX4, D-70442 Stuttgart, Germany. RP Piredda, G (reprint author), Univ Rochester, Inst Opt, Rochester, NY 14627 USA. EM piredda@optics.rochester.edu NR 24 TC 32 Z9 32 U1 0 U2 4 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0740-3224 J9 J OPT SOC AM B JI J. Opt. Soc. Am. B-Opt. Phys. PD JUN PY 2008 VL 25 IS 6 BP 945 EP 950 DI 10.1364/JOSAB.25.000945 PG 6 WC Optics SC Optics GA 319QM UT WOS:000257178800025 ER PT J AU Vieitez, P Gomez, O Uceda, ER Vera, ME Molina-Holgado, E AF Vieitez, Paula Gomez, Oscar Uceda, Esther R. Vera, Maria Eugenia Molina-Holgado, Eduardo TI Systemic and local effects of angiotensin II blockade in experimental diabetic nephropathy SO JOURNAL OF THE RENIN-ANGIOTENSIN-ALDOSTERONE SYSTEM LA English DT Article DE anglotensin receptor blockers; diabetic nephiropathy; goomerull; growth factors; remin-anglotensin system ID ENDOTHELIAL GROWTH-FACTOR; NECROSIS-FACTOR-ALPHA; FACTOR GENE-EXPRESSION; FACTOR-BETA; RAT GLOMERULI; MESANGIAL CELLS; INDUCTION; KIDNEY; ALBUMINURIA; RETINOPATHY AB Introduction. Our objective was to evaluate the effect of blocking the renin-angiotensin system (RAS) on the expression of transforming growth factor-beta 1 (TGF-beta 1), platelet derived growth factor-B (PDGF-B), tumour necrosis factor-alpha (TNF-alpha) and vascular endothelial growth factor (VEGF) in diabetic kidney glomeruli. Materials and Method. 1) Uninephrectomised streptozotocin induced diabetic rats were treated during eight months with vehicle (CD) or irbesartan (ID). Uninephrectomised non-diabetic rats were used as control group (ND). Protein urinary excretion and morphological renal damage were analysed. Glomerular expression of TGF-beta 1, PDGF-B, VEGF and TNF-alpha were evaluated by Western blot and Immunchistochemistry. 2) Isolated glomeruli of diabetic rats were incubated 24-hours in the presence of different doses of irbesartan. Glomerular expression of TGF-beta 1, PDGF-B, TNF-alpha and VEGF were determined by Western blot. Results. ND and ID presented lower renal injury and proteinuria than CD (p < 0.05). Glomerular expression of TGF-beta 1, PDGF-B, TNF-alpha and VEGF were similar in ND and ID, but lower than in CD (p < 0.05). In addition, in isolated diabetic rat glomeruli, irbesartan reduced the content of all these factors. Conclusion. Systemic and local administration of irbesartan lowers glomerular expression of TGF-beta 1, PDGF-B, VEGF and TNF-alpha. These data suggest that part of the effect of lowering the expression of these growth factors and cytokines is due to a direct blockade of glomerular RAS. C1 [Gomez, Oscar; Molina-Holgado, Eduardo] Parapleg Natl Hosp, Dept Expt Neurol, Lab Neuroinflammat, Toledo, Spain. [Vieitez, Paula; Vera, Maria Eugenia] CSIC, Inst Ramon Y Cajal, Dept Endocrinol, Madrid, Spain. [Uceda, Esther R.] NASA, Ames Res Ctr, Div Life Sci, Moffett Field, CA 94035 USA. RP Gomez, O (reprint author), Parapleg Natl Hosp, Dept Expt Neurol, Lab Neuroinflammat, Toledo, Spain. EM vieitezp@yahoo.com; ogomezt@sescam.jccm.es RI Molina-Holgado, Eduardo/C-2714-2008; Gomez, Oscar/F-7114-2016 OI Molina-Holgado, Eduardo/0000-0001-6693-1682; Gomez, Oscar/0000-0001-5492-3343 NR 42 TC 23 Z9 28 U1 0 U2 0 PU J R A A S LTD PI BIRMINGHAM PA EDGBASTON HOUSE, 3 DUCHESS PLACE, EDGBASTON, BIRMINGHAM B16 8NH, ENGLAND SN 1470-3203 J9 J RENIN-ANGIO-ALDO S JI J. Renin-Angiotensin-Aldosterone Syst. PD JUN PY 2008 VL 9 IS 2 BP 96 EP 102 DI 10.3317/jraas.2008.018 PG 7 WC Peripheral Vascular Disease SC Cardiovascular System & Cardiology GA 320HF UT WOS:000257223600006 PM 18584585 ER PT J AU Chaloupka, M Work, TM Balazs, GH Murakawa, SKK Morris, R AF Chaloupka, Milani Work, Thierry M. Balazs, George H. Murakawa, Shawn K. K. Morris, Robert TI Cause-specific temporal and spatial trends in green sea turtle strandings in the Hawaiian Archipelago (1982-2003) SO MARINE BIOLOGY LA English DT Article ID SOMATIC GROWTH DYNAMICS; GULF-OF-MEXICO; CHELONIA-MYDAS; MARINE DEBRIS; FIBROPAPILLOMATOSIS; MORTALITY; PATTERNS; RESIDENT; RECOVERY; ISLANDS AB We investigated cause-specific temporal and spatial trends in sea turtle strandings in the Hawaiian Archipelago. Five species of sea turtle were recorded in 3,861 strandings over a 22-year period (1982-2003). Green turtles comprised 97% of these strandings with size and gender composition reflecting the demographic structure of the resident green turtle population and relative green turtle abundance in Hawaiian waters. The cause of strandings was determined by necropsy based on a complete gross external and internal examination. Totally 75% of the 3,732 green turtle strandings were from Oahu where strandings occur year-round. The most common known cause of the green turtle strandings was the tumour-forming disease, fibropapillomatosis (28%) followed by hook-and-line fishing gear-induced trauma (7%), gillnet fishing gear-induced trauma (5%), boat strike (2.5%), and shark attack (2.7%). Miscellaneous causes comprised 5.4% of strandings whereas 49% of green turtle strandings could not be attributed to any known cause. Green turtle strandings attributable to boat strike were more likely from Kauai and Oahu while fibropapilloma strandings were more likely from Oahu and Maui. Hook-and-line gear strandings were more likely from Oahu due to higher per capita inshore fishing effort. The specific mortality rate (conditional probability) for fibropapillomatosis was 88%, 69% for gillnet gear and 52% for hook-and-line gear. The probability of a dead green turtle stranding increased from 1982 but levelled off by the mid-1990s. The declining mortality risk was because the prevalence and severity of fibropapillomatosis has decreased recently and so has the mortality risk attributable to gillnet gear. Despite exposure to disease and inshore fishing gears, the Hawaiian green turtle stock continues to recover following protection since the late 1970s. Nevertheless, measures to reduce incidental capture of sea turtles in coastal Hawaiian fisheries would be prudent, especially since strandings attributable to hook-and-line fishing gear have increased steadily since 1982. C1 [Chaloupka, Milani] Univ Queensland, Ecol Modelling Serv Pty Ltd, St Lucia, Qld 4067, Australia. [Work, Thierry M.] USGS Natl Wildlife Hlth Ctr, Honolulu Field Stn, Honolulu, HI 96850 USA. [Balazs, George H.; Murakawa, Shawn K. K.] NOAA, Natl Marine Fisheries Serv, Pacific Isl Fisheries Sci Ctr, Honolulu, HI 96822 USA. RP Chaloupka, M (reprint author), Univ Queensland, Ecol Modelling Serv Pty Ltd, POB 6150, St Lucia, Qld 4067, Australia. EM m.chaloupka@uq.edu.au RI Work, Thierry/F-1550-2015 OI Work, Thierry/0000-0002-4426-9090 NR 41 TC 45 Z9 48 U1 3 U2 34 PU SPRINGER HEIDELBERG PI HEIDELBERG PA TIERGARTENSTRASSE 17, D-69121 HEIDELBERG, GERMANY SN 0025-3162 EI 1432-1793 J9 MAR BIOL JI Mar. Biol. PD JUN PY 2008 VL 154 IS 5 BP 887 EP 898 DI 10.1007/s00227-008-0981-4 PG 12 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 307TC UT WOS:000256340200013 ER PT J AU Kohout, T Kletetschka, G Elbra, T Adachi, T Mikula, V Pesonen, LJ Schnabl, P Slechta, S AF Kohout, T. Kletetschka, G. Elbra, T. Adachi, T. Mikula, V. Pesonen, L. J. Schnabl, P. Slechta, S. TI Physical properties of meteorites-Applications in space missions to asteroids SO METEORITICS & PLANETARY SCIENCE LA English DT Article ID MAGNETIC CLASSIFICATION; ORDINARY CHONDRITES; STONY METEORITES; POROSITY; DENSITY AB Based on reflectance spectroscopy and chemical/mineralogical remote sensing methods, it is generally assumed that asteroids are parent bodies for most meteorites reaching the Earth. However, more detailed observations indicate that differences exist in composition between asteroids and meteorites resulting in difficulties when searching for meteorite-asteroid match. We show that among other physical parameters the magnetic susceptibility of an asteroid can be determined remotely from the magnetic induction by solar wind using an orbiting spacecraft or directly using the AC coil on the lander, or it can be measured in samples returned to the laboratory. The shape corrected value of the true magnetic susceptibility of an asteroid can be compared to those of meteorites in the existing database, allowing closer match between asteroids and meteorites. The database of physical properties contains over 700 samples and was recently enlarged with measurements of meteorites in European museums using mobile laboratory facility. C1 [Kohout, T.; Elbra, T.; Pesonen, L. J.] Univ Helsinki, Dept Phys, FIN-00014 Helsinki, Finland. [Kohout, T.; Schnabl, P.; Slechta, S.] Charles Univ Prague, Dept Appl Phys, Prague, Czech Republic. [Kohout, T.; Kletetschka, G.; Schnabl, P.; Slechta, S.] Acad Sci Czech Republic, Inst Geol, Prague, Czech Republic. [Adachi, T.; Mikula, V.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Kletetschka, G.; Adachi, T.; Mikula, V.] Catholic Univ Amer, Dept Phys, Washington, DC 20064 USA. RP Kohout, T (reprint author), Univ Helsinki, Dept Phys, FIN-00014 Helsinki, Finland. EM tomas.kohout@helsinki.fi RI Kohout, Tomas/C-1394-2008; Kletetschka, Gunther/C-9996-2011 OI Kohout, Tomas/0000-0003-4458-3650; Kletetschka, Gunther/0000-0002-0645-9037 FU Academy of Finland; Sohlberg Delegation [NSF EAR-0609609]; Vaisalan Foundation; Institutional Research Plan of the GLI AS CR [CEZ AV0Z30130516] FX This work was financially supported by Academy of Finland project, Sohlberg Delegation research grant, NSF EAR-0609609, Vaisalan Foundation travel grant, and the Institutional Research Plan of the GLI AS CR, v.v.i. no. CEZ AV0Z30130516. We would like to thank V. Kohout for his help with the meteorite measurements, M. Acuna for his consultations, and M. Lehtinen (Geological Museum, University of Helsinki, Finland), H. Parnaste (Geological Survey of Estonia, Tallinn), J. Plado (Tartu University, Estonia), B. Poshkiene (Geology and Mineralogy Museum, Vilnius, Lithuania), E. Rudnickaite and G. Motuza (Vilnius University, Lithuania), J. Biala and J. Szubiakowski (Planetarium and Observatory Olsztyn, Poland), O. Kikay-Szabo (Geological Institute of Hungary, Budapest, Hungary), T. Weiszburg (Eotvos L. University, Budapest, Hungary), A. Embey-Isztin (Museum of Natural History, Budapest, Hungary), M. Bukovanska (National Museum, Prague, Czech Republic), A. Martaus and B. Kratochvil (Chemical University, Prague, Czech Republic), A. Greshake (Humboldt University of Berlin, Germany), A. Bischoff (University of Munster, Germany), G. Raade (University of Oslo, Norway), J. O. Nystrom (Swedish Museum of Natural History, Stockholm, Sweden) for their cooperation and help in providing access to the meteorite collections. NR 20 TC 12 Z9 12 U1 0 U2 8 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 1086-9379 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD JUN PY 2008 VL 43 IS 6 BP 1009 EP 1020 PG 12 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 361RY UT WOS:000260146000003 ER PT J AU Weissman, PR Lowry, SC AF Weissman, Paul R. Lowry, Stephen C. TI Structure and density of cometary nuclei SO METEORITICS & PLANETARY SCIENCE LA English DT Article ID LONG-PERIOD COMETS; DEEP IMPACT; COLLISIONAL EVOLUTION; TIDAL DISRUPTION; CRATER CHAINS; TIME SCALES; KUIPER-BELT; OORT CLOUD; MODEL; SHOEMAKER-LEVY-9 AB Understanding the nature of the cometary nucleus remains one of the major problems in solar system science. Whipple's (1950) icy conglomerate model has been very successful at explaining a range of cometary phenomena, including the source of cometary activity and the nongravitational orbital motion of the nuclei. However, the internal structure of the nuclei is still largely unknown. We review herein the evidence for cometary nuclei as fluffy aggregates or primordial rubble piles, as first proposed by Donn et al. (1985) and Weissman (1986). These models assume that cometary nuclei are weakly bonded aggregations of smaller, icy-conglomerate planetesimals, possibly held together only by self-gravity. Evidence for this model comes from studies of the accretion and subsequent evolution of material in the solar nebula, from observations of disrupted comets, and in particular comet Shoemaker-Levy 9, from measurements of the ensemble rotational properties of observed cometary nuclei, and from recent spacecraft missions to comets. Although the evidence for rubble pile nuclei is growing, the eventual answer to this question will likely not come until we can place a spacecraft in orbit around a cometary nucleus and study it in detail over many months to years. ESA's Rosetta mission, now en route to comet 67P/Churyumov-Gerasimenko, will provide that opportunity. C1 [Weissman, Paul R.] CALTECH, Jet Prop Lab, Div Sci, Pasadena, CA 91109 USA. [Lowry, Stephen C.] Queens Univ Belfast, Dept Phys & Astron, Belfast BT7 1NN, Antrim, North Ireland. RP Weissman, PR (reprint author), CALTECH, Jet Prop Lab, Div Sci, 4800 Oak Grove Dr,Mail Stop 183-301, Pasadena, CA 91109 USA. EM paul.r.weissman@jpl.nasa.gov FU NASA Planetary Astronomy Program; Jet Propulsion Laboratory; NASA; The Leverhulme Trust FX We thank the referee, Casey Lisse, for very useful comments and discussion on an earlier draft of this paper. This work was supported in part by the NASA Planetary Astronomy Program and was performed in part at the Jet Propulsion Laboratory under a contract with NASA. The Leverhulme Trust also provided support. NR 69 TC 13 Z9 13 U1 0 U2 4 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 1086-9379 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD JUN PY 2008 VL 43 IS 6 BP 1033 EP 1047 PG 15 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 361RY UT WOS:000260146000005 ER PT J AU Gaskell, RW Barnouin-Jha, OS Scheeres, DJ Konopliv, AS Mukai, T Abe, S Saito, J Ishiguro, M Kubota, T Hashimoto, T Kawaguchi, J Yoshikawa, M Shirakawa, K Kominato, T Hirata, N Demura, H AF Gaskell, R. W. Barnouin-Jha, O. S. Scheeres, D. J. Konopliv, A. S. Mukai, T. Abe, S. Saito, J. Ishiguro, M. Kubota, T. Hashimoto, T. Kawaguchi, J. Yoshikawa, M. Shirakawa, K. Kominato, T. Hirata, N. Demura, H. TI Characterizing and navigating small bodies with imaging data SO METEORITICS & PLANETARY SCIENCE LA English DT Article AB Recent advances in the characterization of small body surfaces with stereophotoclinometry are discussed. The principal data output is an ensemble of landmark maps (L-maps), high-resolution topography/albedo maps of varying resolution that tile the surface of tile body. Because they can have a resolution comparable to the best images, and can be located on a global reference frame to high accuracy, L-maps provide a significant improvement in discriminatory power for studies of small bodies, ranging from regolith processes to interior structure. These techniques are now being used to map larger bodies such as the Moon and Mercury. L-maps are combined to produce a standard global topography model (GTM) with about 1.57 million vectors and having a wide variety of applications. They call also be combined to produce high-resolution topography maps that describe local areas with much greater detail than the GTM. When combined with nominal predictions from other data sources and available data from other instruments such as LIDAR or RADAR, solutions for the spacecraft position and camera pointing are the most accurate available. Examples are drawn from studies of Phobos, Eros, and Itokawa, including surface characterization, gravity analysis, spacecraft navigation, and incorporation of LIDAR or RADAR data. This work has important implications for potential future missions such as Deep Interior and the level of navigation and science that can be achieved. C1 [Gaskell, R. W.] Planetary Sci Inst, Tucson, AZ 85712 USA. [Barnouin-Jha, O. S.] Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. [Scheeres, D. J.] Univ Colorado, Colorado Ctr Astrodynam Res, Dept Aerosp Engn Sci, Boulder, CO 80309 USA. [Konopliv, A. S.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Mukai, T.] Kobe Univ, Grad Sch Sci & Technol, Kobe, Hyogo 6578501, Japan. [Ishiguro, M.; Kubota, T.; Hashimoto, T.; Kawaguchi, J.; Yoshikawa, M.] Japan Aerosp Explorat Agcy, Inst Space & Astronaut Sci, Dept Spacecraft Engn, Kanagawa 2298510, Japan. [Shirakawa, K.; Kominato, T.] NEC Aerosp Syst, Tokyo 1838551, Japan. [Hirata, N.; Demura, H.] Univ Aizu, Sch Engn & Comp Sci, Aizu Wakamatsu, Fukushima 9658580, Japan. [Saito, J.] PASCO Corp, Ctr Res & Dev, Tokyo 1530043, Japan. [Abe, S.] Natl Cent Univ, Grad Inst Astron, Jhongli 320, Taoyuan County, Taiwan. RP Gaskell, RW (reprint author), Planetary Sci Inst, 1700 E Ft Lowell Rd,Suite 106, Tucson, AZ 85712 USA. EM rgaskell@psi.edu RI Barnouin, Olivier/I-7475-2015 OI Barnouin, Olivier/0000-0002-3578-7750 NR 18 TC 64 Z9 64 U1 1 U2 7 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 1086-9379 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD JUN PY 2008 VL 43 IS 6 BP 1049 EP 1061 PG 13 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 361RY UT WOS:000260146000006 ER PT J AU Yang, Y Gupta, MC Zalameda, JN Winfree, WP AF Yang, Y. Gupta, M. C. Zalameda, J. N. Winfree, W. P. TI Dispersion behaviour, thermal and electrical conductivities of carbon nanotube-polystyrene nanocomposites SO MICRO & NANO LETTERS LA English DT Article ID POLYMER COMPOSITES; MECHANICAL-PROPERTIES; EPOXY COMPOSITES; MORPHOLOGY AB The dispersion behaviour, thermal and electrical conductivities of carbon nanotube-polystyrene nanocomposites were investigated. The dispersion of carbon nanotubes ( CNTs) in the nanocomposites was characterised by scanning electron microscope; it was observed that CNTs were homogeneously dispersed and embedded within the polystyrene matrix. The thermal conductivity of the nanocomposites were measured with a through transmission thermal inspection system at room temperature. The results showed that the thermal conductivity increased with an increase in CNT content, and the nanocomposite loaded 5 wt% CNTs exhibited a 120% enhancement in thermal conductivity. The correlation between the dispersion behaviour and thermal and electrical conductivities was discussed. In addition, it was demonstrated that CNT-polymer nanocomposites give larger increases in thermal and electrical conductivities for the same loading of carbon nanofibres, graphite powders and silver nanoparticles. C1 [Yang, Y.; Gupta, M. C.] Univ Virginia, Charles L Brown Dept Elect & Comp Engn, Charlottesville, VA 22904 USA. [Zalameda, J. N.] USA, Res Lab, NASA Langley Res Ctr, Nondestruct Evaluat Sci Branch, Hampton, VA 23681 USA. [Winfree, W. P.] NASA, Langley Res Ctr, Nondestruct Evaluat Sci Branch, Hampton, VA 23681 USA. RP Yang, Y (reprint author), Univ Virginia, Charles L Brown Dept Elect & Comp Engn, Charlottesville, VA 22904 USA. EM yonglaiyang@hotmail.com NR 25 TC 26 Z9 27 U1 1 U2 25 PU INST ENGINEERING TECHNOLOGY-IET PI HERTFORD PA MICHAEL FARADAY HOUSE SIX HILLS WAY STEVENAGE, HERTFORD SG1 2AY, ENGLAND SN 1750-0443 J9 MICRO NANO LETT JI Micro Nano Lett. PD JUN PY 2008 VL 3 IS 2 BP 35 EP 40 DI 10.1049/mnl:20070073 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary SC Science & Technology - Other Topics; Materials Science GA 320PX UT WOS:000257248600001 ER PT J AU Sharma, CS Sarkar, S Periyakaruppan, A Ravichandran, P Sadanandan, B Ramesh, V Thomas, R Hall, JC Wilson, BL Ramesh, GT AF Sharma, Chidananda S. Sarkar, Shubhashish Periyakaruppan, Adaikkappan Ravichandran, Prabakaran Sadanandan, Bindu Ramesh, Vani Thomas, Renard Hall, Joseph C. Wilson, Bobby L. Ramesh, Govindarajan T. TI Simulated microgravity activates apoptosis and NF-kappa B in mice testis SO MOLECULAR AND CELLULAR BIOCHEMISTRY LA English DT Article DE microgravity; apoptosis; caspase; NF-kappa B; testosterone ID ARF TUMOR-SUPPRESSOR; GERM-CELL APOPTOSIS; TESTOSTERONE WITHDRAWAL; SIGNALING PATHWAYS; HORMONE TREATMENT; SPACE-FLIGHT; ADULT-RAT; IN-VITRO; MODEL; SPERMATOGENESIS AB Microgravity is known to have significant effect on all aspects of reproductive function in animal models. Recent studies have also shown that microgravity induces changes at the cellular level, including apoptosis. Our effort here was to study the effect of simulated microgravity on caspase-8 and the caspase-3 activities, the effectors of the apoptotic pathway and on the transcription factor NF-kappa B a signaling molecule in mouse testis. Morey-Holton hind limb suspension model was used to simulate microgravity. Caspase-8 and 3 fluorometric assays were carried out and HLS mice testis exhibited a 51% increase in caspase-8 and caspase-3 compared to the controls. A sandwich ELISA-based immunoassay was carried out for detection of NF-kappa B which again significantly increased in the test mice. Testosterone levels were measured using an ELISA kit and in HLS mice the decrease was significant. There was also a significant decrease in testis weight in the test mice. Simulated microgravity activates caspase 8, 3 and NF-kappa B necessary to stimulate the apoptotic pathway in mice testis. This may account for the drop in testis weight and testosterone level further affecting testicular physiology and function. C1 [Sharma, Chidananda S.; Ravichandran, Prabakaran; Ramesh, Vani; Hall, Joseph C.; Ramesh, Govindarajan T.] Norfolk State Univ, Dept Biol, Mol Toxicol Lab, Ctr Biotechnol & Biomed Sci, Norfolk, VA 23504 USA. [Sarkar, Shubhashish; Periyakaruppan, Adaikkappan; Sadanandan, Bindu; Thomas, Renard; Wilson, Bobby L.; Ramesh, Govindarajan T.] Texas So Univ, NASA, Univ Res Ctr, Houston, TX 77004 USA. RP Ramesh, GT (reprint author), Norfolk State Univ, Dept Biol, Mol Toxicol Lab, Ctr Biotechnol & Biomed Sci, Norfolk, VA 23504 USA. EM gtramesh@nsu.edu RI Periyakaruppan, Adaikkappan/B-7398-2013 OI Periyakaruppan, Adaikkappan/0000-0002-0395-6564 FU NIMHD NIH HHS [P20 MD001822, 1P20MD001822-1, P20 MD001822-04] NR 45 TC 16 Z9 20 U1 1 U2 4 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0300-8177 J9 MOL CELL BIOCHEM JI Mol. Cell. Biochem. PD JUN PY 2008 VL 313 IS 1-2 BP 71 EP 78 DI 10.1007/s11010-008-9743-3 PG 8 WC Cell Biology SC Cell Biology GA 304DU UT WOS:000256091000009 PM 18385949 ER PT J AU Kopp, A Barmina, O Hamilton, AM Higgins, L McIntyre, LM Jones, CD AF Kopp, Artyom Barmina, Olga Hamilton, Andrew M. Higgins, Laura McIntyre, Lauren M. Jones, Corbin D. TI Evolution of gene expression in the Drosophila olfactory system SO MOLECULAR BIOLOGY AND EVOLUTION LA English DT Article DE olfactory receptors; Drosophila sechellia; gene expression; microarrays; regulatory evolution; host plant preferences ID MELANOGASTER SPECIES SUBGROUP; ODORANT-BINDING PROTEINS; FALSE DISCOVERY RATE; RECEPTOR GENES; HOST-PLANT; ECOLOGICAL SPECIALIZATION; REPRODUCTIVE ISOLATION; OVIPOSITION BEHAVIOR; TASTE RECEPTORS; PHEROMONE AB Host plant shifts by phytophagous insects play a key role in insect evolution and plant ecology. Such shifts often involve major behavioral changes as the insects must acquire an attraction and/or lose the repulsion to the new host plant's odor and taste. The evolution of chemotactic behavior may be due, in part, to gene expression changes in the peripheral sensory system. To test this hypothesis, we compared gene expression in the olfactory organs of Drosophila sechellia, a narrow ecological specialist that feeds on the fruit of Morinda citrifolia, with its close relatives Drosophila simulans and Drosophila melanogaster, which feed on a wide variety of decaying plant matter. Using whole-genome microarrays and quantitative polymerase chain reaction, we surveyed the entire repertoire of Drosophila odorant receptors (ORs) and odorant-binding proteins (OBPs) expressed in the antennae. We found that the evolution of OR and OBP expression was accelerated in D. sechellia compared both with the genome average in that species and with the rate of OR and OBP evolution in the other species. However, some of the gene expression changes that correlate with D. sechellia's increased sensitivity to Morinda odorants may predate its divergence from D. simulans. Interspecific divergence of olfactory gene expression cannot be fully explained by changes in the relative abundance of different sensilla as some ORs and OBPs have evolved independently of other genes expressed in the same sensilla. A number of OR and OBP genes are upregulated in D. sechellia compared with its generalist relatives. These genes include Or22a, which likely responds to a key odorant of M. citrifolia, and several genes that are yet to be characterized in detail. Increased expression of these genes in D. sechellia may have contributed to the evolution of its unique chemotactic behavior. C1 [Kopp, Artyom; Barmina, Olga; Hamilton, Andrew M.] Univ Calif Davis, Sect Evolut & Ecol, Davis, CA 95616 USA. [Higgins, Laura] Indiana Univ, Dept Biol, Bloomington, IN 47405 USA. [Higgins, Laura] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. [McIntyre, Lauren M.] Univ Florida, Genet Inst, Gainesville, FL 32611 USA. [McIntyre, Lauren M.] Univ Florida, Dept Mol Genet & Microbiol, Gainesville, FL 32611 USA. [Jones, Corbin D.] Univ N Carolina, Dept Biol, Chapel Hill, NC USA. [Jones, Corbin D.] Univ N Carolina, Carolina Ctr Genome Sci, Chapel Hill, NC USA. RP Kopp, A (reprint author), Univ Calif Davis, Sect Evolut & Ecol, Davis, CA 95616 USA. EM akopp@ucdavis.edu RI McIntyre, Lauren/J-8414-2012 OI McIntyre, Lauren/0000-0002-0077-3359 FU NIDDK NIH HHS [DK35747, P30 DK035747]; NIGMS NIH HHS [1R01GM077618-01A1, 1R24GM065513-01, R01 GM077618, R24 GM065513] NR 65 TC 35 Z9 36 U1 6 U2 28 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0737-4038 J9 MOL BIOL EVOL JI Mol. Biol. Evol. PD JUN PY 2008 VL 25 IS 6 BP 1081 EP 1092 DI 10.1093/molbev/msn055 PG 12 WC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity GA 299LX UT WOS:000255758200008 PM 18296696 ER PT J AU Damineli, A Hillier, DJ Corcoran, MF Stahl, O Groh, JH Arias, J Teodoro, M Morrell, N Gamen, R Gonzalez, F Leister, NV Levato, H Levenhagen, RS Grosso, M Colombo, JFA Wallerstein, G AF Damineli, A. Hillier, D. J. Corcoran, M. F. Stahl, O. Groh, J. H. Arias, J. Teodoro, M. Morrell, N. Gamen, R. Gonzalez, F. Leister, N. V. Levato, H. Levenhagen, R. S. Grosso, M. Colombo, J. F. Albacete Wallerstein, G. TI A multispectral view of the periodic events in eta Carinae SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE stars : general; stars : individual : eta Carinae ID SPECTROSCOPIC EVENT; HOMUNCULUS NEBULA; EMISSION-LINES; 2003.5 MINIMUM; WEIGELT BLOBS; BINARY; STAR; CAR; VARIABILITY; LAMBDA-4686 AB A full description of the 5.5-yr low excitation events in. Carinae is presented. We show that they are not as simple and brief as previously thought, but a combination of two components. The first, the slow variation component, is revealed by slow changes in the ionization level of circumstellar matter across the whole cycle and is caused by gradual changes in the wind wind collision shock-cone orientation, angular opening and gaseous content. The second, the collapse component, is restricted to around the minimum, and is due to a temporary global collapse of the wind-wind collision shock. High-energy photons (E > 16 eV) from the companion star are strongly shielded, leaving the Weigelt objects at low-ionization state for more than six months. High-energy phenomena are sensitive only to the collapse, low energy only to the slow variation and intermediate energies to both components. Simple eclipses and mechanisms effective only near periastron (e. g. shell ejection or accretion on to the secondary star) cannot account for the whole 5.5-yr cycle. We find anti-correlated changes in the intensity and the radial velocity of P Cygni absorption profiles in Fe II lambda 6455 and He I lambda 7065 lines, indicating that the former is associated to the primary and the latter to the secondary star. We present a set of light curves representative of the whole spectrum, useful for monitoring the next event (2009 January 11). C1 [Damineli, A.; Groh, J. H.; Teodoro, M.; Leister, N. V.; Levenhagen, R. S.] Univ Sao Paulo, Inst Astron Geofis & Ciencias Atomsfericas, BR-05508900 Sao Paulo, Brazil. [Hillier, D. J.] Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. [Corcoran, M. F.] NASA, GSFC, CRESST & Xray Astrophys Lab, Greenbelt, MD 20771 USA. [Corcoran, M. F.] Univ Space Res Assoc, Columbia, MD 21044 USA. [Stahl, O.] Heidelberg Univ, ZAH, D-69117 Heidelberg, Germany. [Colombo, J. F. Albacete] Fac Ciencias Astron & Geogis La Plata, Buenos Aires, DF, Argentina. [Gamen, R.; Gonzalez, F.; Levato, H.; Grosso, M.] Complejo Astron El Leoncito, San Juan, Argentina. [Arias, J.] Univ La Serena, Dept Fis, La Serena, Chile. [Morrell, N.] Carnegie Observ, Las Campanas Observ, La Serena, Chile. [Wallerstein, G.] Univ Washington, Dept Astron, Seattle, WA 98195 USA. RP Damineli, A (reprint author), Univ Sao Paulo, Inst Astron Geofis & Ciencias Atomsfericas, Rua Matao 1226,Cidade Univ, BR-05508900 Sao Paulo, Brazil. EM damineli@astro.iag.usp.br RI Damineli, Augusto/D-8210-2012; Levenhagen, Ronaldo/A-1043-2008; Teodoro, Mairan/H-9123-2013; Gamen, Roberto/A-1728-2015 OI Damineli, Augusto/0000-0002-7978-2994; Levenhagen, Ronaldo/0000-0003-2499-9325; NR 56 TC 44 Z9 44 U1 0 U2 4 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0035-8711 EI 1365-2966 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD JUN 1 PY 2008 VL 386 IS 4 BP 2330 EP 2344 DI 10.1111/j.1365-2966.2008.13214.x PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 302BR UT WOS:000255944100057 ER PT J AU Koster, RD Bell, TL Reichle, RH Suarez, MJ Schubert, SD AF Koster, Randal D. Bell, Thomas L. Reichle, Rolf H. Suarez, Max J. Schubert, Siegfried D. TI Using observed spatial correlation structures to increase the skill of subseasonal forecasts SO MONTHLY WEATHER REVIEW LA English DT Article ID ATMOSPHERE COUPLING EXPERIMENT; SEA-SURFACE TEMPERATURE; SOIL-MOISTURE; UNITED-STATES; JULY 1993; PART I; LAND; SIMULATIONS; PRECIPITATION; VARIABILITY AB Model deficiencies limit a subseasonal or seasonal forecast system's ability to produce accurate predictions. In this paper, an approach for transforming the output of a forecast system into a revised forecast is presented; it is designed to correct for some of the deficiencies in the system (particularly those associated with the spatial correlation structures of the forecasted fields) and thereby increase forecast skill. The approach, based on the joint consideration of the correlation structures present in the observational record and the inherent potential predictability of the model, is tested on a preexisting subseasonal forecast experiment. It is shown to produce modest but significant increases in the accuracy of forecasted precipitation and near-surface air temperature at monthly time scales. C1 [Koster, Randal D.; Reichle, Rolf H.; Suarez, Max J.; Schubert, Siegfried D.] NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Greenbelt, MD 20771 USA. [Bell, Thomas L.] NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Climate & Radiat Branch,Atmospher Sci Div, Greenbelt, MD 20771 USA. [Reichle, Rolf H.] Univ Maryland, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21201 USA. RP Koster, RD (reprint author), NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Code 610-1, Greenbelt, MD 20771 USA. EM randal.d.koster@nasa.gov RI Reichle, Rolf/E-1419-2012; Koster, Randal/F-5881-2012; Bell, Thomas/G-5425-2012 OI Koster, Randal/0000-0001-6418-6383; NR 36 TC 3 Z9 3 U1 0 U2 2 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PD JUN PY 2008 VL 136 IS 6 BP 1923 EP 1939 DI 10.1175/2007MWR2255.1 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 320MN UT WOS:000257239300006 ER PT J AU Jiang, XA Waliser, DE Wheeler, MC Jones, C Lee, MI Schuert, SD AF Jiang, Xianan Waliser, Duane E. Wheeler, Matthew C. Jones, Charles Lee, Myong-In Schuert, Siegfried D. TI Assessing the skill of an all-season statistical forecast model for the Madden-Julian oscillation SO MONTHLY WEATHER REVIEW LA English DT Article ID EXTENDED-RANGE PREDICTION; INTRASEASONAL OSCILLATIONS; 60-DAY OSCILLATION; PATTERN-ANALYSIS; SUMMER MONSOON; TIME SCALES; PREDICTABILITY; VARIABILITY; INDEX; ENSO AB Motivated by an attempt to augment dynamical models in predicting the Madden-Julian oscillation (MJO), and to provide a realistic benchmark to those models, the predictive skill of a multivariate lag-regression statistical model has been comprehensively explored in the present study. The predictors of the benchmark model are the projection time series of the leading pair of EOFs of the combined fields of equatorially averaged outgoing longwave radiation (OLR) and zonal winds at 850 and 200 hPa, derived using the approach of Wheeler and Hendon. These multivariate EOFs serve as an effective filter for the MJO without the need for bandpass filtering, making the statistical forecast scheme feasible for the real-time use. Another advantage of this empirical approach ties in the consideration of the seasonal dependence of the regression parameters, making it applicable for forecasts all year-round. The forecast model exhibits useful extended-range skill for a real-time MJO forecast. Predictions with a correlation skill of greater than 0.3 (0.5) between predicted and observed unfiltered (EOF filtered) fields still can be detected over some regions at a lead time of 15 days, especially for boreal winter forecasts. This predictive skill is increased significantly when there are strong MJO signals at the initial forecast time. The analysis also shows that predictive skill for the upper-tropospheric winds is relatively higher than for the low-level winds and convection signals. Finally, the capability of this empirical model in predicting the MJO is further demonstrated by a case study of a real-time "hindcast" during the 2003/04 winter. Predictive skill demonstrated in this study provides an estimate of the predictability of the MJO and a benchmark for the dynamical extended-range models. C1 [Jiang, Xianan; Waliser, Duane E.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Wheeler, Matthew C.] Bur Meteorol Res Ctr, Melbourne, Australia. [Jones, Charles] Univ Calif Santa Barbara, Inst Computat Earth Syst Sci, Santa Barbara, CA 93106 USA. [Lee, Myong-In; Schuert, Siegfried D.] NASA, Goddard Space Flight Ctr, Global Model & Assimilat Off, Greenbelt, MD 20771 USA. RP Jiang, XA (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,MS 183-501, Pasadena, CA 91109 USA. EM xianan.jiang@jpl.nasa.gov RI Jiang, Xianan/A-2283-2012; Wheeler, Matthew/C-9038-2011; Jones, Charles/I-4574-2012; OI Wheeler, Matthew/0000-0002-9769-1973; Jones, Charles/0000-0003-4808-6977; Lee, Myong-In/0000-0001-8983-8624 NR 46 TC 49 Z9 57 U1 0 U2 6 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 EI 1520-0493 J9 MON WEATHER REV JI Mon. Weather Rev. PD JUN PY 2008 VL 136 IS 6 BP 1940 EP 1956 DI 10.1175/2007MWR2305.1 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 320MN UT WOS:000257239300007 ER PT J AU Ehlmann, BL Mustard, JF Fassett, CI Schon, SC Head, JW Marais, DJD Grant, JA Murchie, SL AF Ehlmann, Bethany L. Mustard, John F. Fassett, Caleb I. Schon, Samuel C. Head, James W., III Marais, David J. Des Grant, John A. Murchie, Scott L. TI Clay minerals in delta deposits and organic preservation potential on Mars SO NATURE GEOSCIENCE LA English DT Article ID OLIVINE; MONTMORILLONITE; PHYLLOSILICATES; DIVERSITY; LIFE AB Clay-rich sedimentary deposits are often sites of organic matter preservation(1,2), and have therefore been sought in Mars exploration(3). However, regional deposits of hydrous minerals, including phyllosilicates and sulphates(4,5), are not typically associated with valley networks and layered sediments that provide geomorphic evidence of surface water transport on early Mars(6-8). The Compact Reconnaissance Imaging Spectrometer for Mars (CRISM)(9) has recently identified phyllosilicates(10) within three lake basins with fans or deltas that indicate sustained sediment deposition: Eberswalde crater(7,11,12), Holden crater(12,13) and Jezero crater(14). Here we use high-resolution data from the Mars Reconnaissance Orbiter (MRO) to identify clay-rich fluvial-lacustrine sediments within Jezero crater, which has a diameter of 45 km. The crater is an open lake basin on Mars with sedimentary deposits of hydrous minerals sourced from a smectite-rich catchment in the Nili Fossae region. We find that the two deltas and the lowest observed stratigraphic layer within the crater host iron-magnesium smectite clay. Jezero crater holds sediments that record multiple episodes of aqueous activity on early Mars. We suggest that this depositional setting and the smectite mineralogy make these deltaic deposits well suited for the sequestration and preservation of organic material. C1 [Ehlmann, Bethany L.; Mustard, John F.; Fassett, Caleb I.; Schon, Samuel C.; Head, James W., III] Brown Univ, Dept Geol Sci, Providence, RI 02912 USA. [Marais, David J. Des] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. [Grant, John A.] Smithsonian Inst, Natl Air & Space Museum, Ctr Earth & Planetary Studies, Washington, DC 20013 USA. [Murchie, Scott L.] Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. RP Ehlmann, BL (reprint author), Brown Univ, Dept Geol Sci, Providence, RI 02912 USA. EM bethany_ehlmann@brown.edu RI Murchie, Scott/E-8030-2015; OI Murchie, Scott/0000-0002-1616-8751; Fassett, Caleb/0000-0001-9155-3804 NR 30 TC 123 Z9 126 U1 10 U2 41 PU NATURE PUBLISHING GROUP PI NEW YORK PA 75 VARICK STREET, 9TH FLOOR, NEW YORK, NY 10013-1917 USA SN 1752-0894 J9 NAT GEOSCI JI Nat. Geosci. PD JUN PY 2008 VL 1 IS 6 BP 355 EP 358 DI 10.1038/ngeo207 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 309BC UT WOS:000256433700010 ER PT J AU Durante, M Cucinotta, FA AF Durante, Marco Cucinotta, Francis A. TI Heavy ion carcinogenesis and human space exploration SO NATURE REVIEWS CANCER LA English DT Review ID DOUBLE-STRAND BREAK; ATOMIC-BOMB SURVIVORS; HIGH-LET RADIATION; HZE-PARTICLE RADIATION; GALACTIC COSMIC-RAYS; ENERGY IRON IONS; GENOMIC INSTABILITY; IONIZING-RADIATION; CANCER-RISKS; CHROMOSOMAL INSTABILITY AB Before the human exploration of Mars or long-duration missions on the earth's moon, the risk of cancer and other diseases from space radiation must be accurately estimated and mitigated. space radiation, comprised of energetic protons and heavy nuclei, has been shown to produce distinct biological damage compared with radiation on earth, leading to large uncertainties in the projection of cancer and other health risks, and obscuring evaluation of the effectiveness of possible countermeasures. Here, we describe how research in cancer radiobiology can support human missions to Mars and other planets. C1 GSI Darmstadt, Biophys Grp, D-64291 Darmstadt, Germany. [Durante, Marco] Univ Naples Federico 2, I-80126 Naples, Italy. [Cucinotta, Francis A.] NASA, Lyndon B Johnson Space Ctr, Space Radiat Program, Houston, TX 77056 USA. RP Durante, M (reprint author), GSI Darmstadt, Biophys Grp, Planckstr 1, D-64291 Darmstadt, Germany. EM M.Durante@gsi.de; Francis.A.Cucinotta@nasa.gov RI Durante, Marco/K-1315-2014; OI Durante, Marco/0000-0002-4615-553X NR 118 TC 230 Z9 235 U1 6 U2 34 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 1474-175X J9 NAT REV CANCER JI Nat. Rev. Cancer PD JUN PY 2008 VL 8 IS 6 BP 465 EP 472 DI 10.1038/nrc2391 PG 9 WC Oncology SC Oncology GA 304KQ UT WOS:000256108800017 PM 18451812 ER PT J AU Jacobson, NS Smialek, JL Eldridge, JI Humphrey, DL AF Jacobson, N. S. Smialek, J. L. Eldridge, J. I. Humphrey, D. L. TI Oxidation of FeCrAlY fibers at low oxygen potentials SO OXIDATION OF METALS LA English DT Article DE oxidation; FeCrAlY; fibers; alloy depletion; transient oxidation; alumina; chromia ID FE-CR-AL; GROWTH-KINETICS; ALLOYS; SCALE; OXIDE; CHROMIUM; ALUMINA; MICROSTRUCTURE; ADHESION AB The oxidation of Fe-15Cr-5Al-0.3Y (wt.%) coupons and 22-mu m-diameter fibers has been studied in a helium atmosphere containing similar to 150 ppm oxygen at temperatures of 750-950 degrees C. Thermogravimetric analysis was used to follow kinetics, and oxide scales were analyzed with scanning-electron microscopy, electron-microprobe analysis, and photostimulated luminescence. The observed kinetics behavior of the coupons and fibers is attributed to effects of both transitional aluminas and aluminum depletion in the alloy. Distinct differences are observed with the fibers as compared to the coupons at 900 and 950 degrees C, but similar behavior is observed at 850 degrees C. Pre-oxidation treatments of the fibers at 1,100 degrees C in air formed a thin layer of alpha-Al2O3 and slowed oxidation dramatically at 850 degrees C. The fibers showed aluminum depletion and formed mixed alumina-chromia scales, which appeared adherent and protective. C1 [Jacobson, N. S.; Smialek, J. L.; Eldridge, J. I.] NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. [Humphrey, D. L.] NASA, Glenn Grp, ASRC Aerosp, Cleveland, OH 44135 USA. RP Jacobson, NS (reprint author), NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. EM nathan.sjacobson@nasa.gov RI Jacobson, Nathan/A-9411-2009 NR 21 TC 2 Z9 2 U1 0 U2 2 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0030-770X J9 OXID MET JI Oxid. Met. PD JUN PY 2008 VL 69 IS 5-6 BP 343 EP 358 DI 10.1007/s11085-008-9101-6 PG 16 WC Metallurgy & Metallurgical Engineering SC Metallurgy & Metallurgical Engineering GA 305CJ UT WOS:000256155100005 ER PT J AU Young, JA Gribakin, GF Lee, CMR Surko, CM AF Young, J. A. Gribakin, G. F. Lee, C. M. R. Surko, C. M. TI Role of combination vibrations in resonant positron annihilation SO PHYSICAL REVIEW A LA English DT Article ID LARGE MOLECULES; THRESHOLD; SPECTRA; STATES; GASES AB Positrons can attach to molecules via vibrational Feshbach resonances, leading to very large annihilation rates. The predictions of a recent theory for this process are validated for deuterated methyl halides where all modes are dipole coupled to the incident positron. Data and analysis are presented for methanol and ethylene, demonstrating the importance of combination and overtone resonances and the ability of the theory to account for these features. The mechanism for these resonances and criteria for their occurrence as well as outstanding questions are discussed. C1 [Young, J. A.; Surko, C. M.] Univ Calif San Diego, Dept Phys, San Diego, CA 92093 USA. [Gribakin, G. F.; Lee, C. M. R.] Queens Univ Belfast, Dept Appl Math & Theoret Phys, Belfast BT7 1NN, Antrim, North Ireland. RP Young, JA (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 18 TC 13 Z9 13 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9926 EI 2469-9934 J9 PHYS REV A JI Phys. Rev. A PD JUN PY 2008 VL 77 IS 6 AR 060702 DI 10.1103/PhysRevA.77.060702 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 321EZ UT WOS:000257288800013 ER PT J AU Boykin, TB Kharche, N Klimeck, G AF Boykin, Timothy B. Kharche, Neerav Klimeck, Gerhard TI Valley splitting in finite barrier quantum wells SO PHYSICAL REVIEW B LA English DT Article ID INVERSION-LAYERS; MAGNETIC-FIELD; SILICON; HETEROSTRUCTURES; SURFACES; STATES; MODEL AB The valley splitting (VS) in a silicon quantum well is calculated as a function of barrier height with both the multiband sp(3)d(5)s(*) model and a simple two-band model. Both models show a strong dependence of the VS on barrier height. For example, in both models some quantum wells exhibit a sharp minimum in the valley-splitting amplitude as the barrier height is changed. From the simple two-band model we obtain analytic approximations for the phases of the bulk states involved in the valley-split doublet, and from these we show that such sharp minima correspond to parity changes in the ground state as the barrier height is increased. The two-band analytic results show a complicated dependence of the valley splitting on barrier height, with the phases essentially being determined by a competition among effective quantum wells of differing length. These analytic results help explain the VS in realistic structures where different finite barrier heights are possible depending on the confining heterojunctions used. C1 [Boykin, Timothy B.] Univ Alabama, Dept Elect & Comp Engn, Huntsville, AL 35899 USA. [Kharche, Neerav; Klimeck, Gerhard] Purdue Univ, Sch Elect & Comp Engn, Network Computat Nanotechnol, W Lafayette, IN 47907 USA. [Klimeck, Gerhard] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Boykin, TB (reprint author), Univ Alabama, Dept Elect & Comp Engn, Huntsville, AL 35899 USA. RI Klimeck, Gerhard/A-1414-2012; Kharche, Neerav/F-4331-2015 OI Klimeck, Gerhard/0000-0001-7128-773X; Kharche, Neerav/0000-0003-1014-6022 NR 32 TC 13 Z9 13 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD JUN PY 2008 VL 77 IS 24 AR 245320 DI 10.1103/PhysRevB.77.245320 PG 8 WC Physics, Condensed Matter SC Physics GA 321FI UT WOS:000257289700079 ER PT J AU Yunes, N Berti, E AF Yunes, Nicolas Berti, Emanuele TI Accuracy of the post-Newtonian approximation: Optimal asymptotic expansion for quasicircular, extreme-mass ratio inspirals SO PHYSICAL REVIEW D LA English DT Article ID SCHWARZSCHILD BLACK-HOLE; GRAVITATIONAL-RADIATION; TEUKOLSKY EQUATION; ANALYTIC SOLUTIONS; COMPACT BINARIES; PARTICLE; ORBIT; WAVES; PERTURBATION; SYSTEMS AB We study the accuracy of the post-Newtonian (PN) approximation and its formal region of validity, by investigating its optimal asymptotic expansion for the quasicircular, adiabatic inspiral of a point particle into a Schwarzschild black hole. By comparing the PN expansion of the energy flux to numerical calculations in the perturbative Teukolsky formalism, we show that (i) the inclusion of higher multipoles is necessary to establish the accuracy of high-order PN terms, and (ii) the region of validity of PN theory is largest at relative O(1/c(6)) (3PN order). The latter result suggests that the series diverges beyond 3PN order, at least in the extreme-mass-ratio limit, probably due to the appearance of logarithmic terms in the energy flux. The study presented here is a first formal attempt to determine the region of validity of the PN approximation using asymptotic analysis. Therefore, it should serve as a template to perform similar studies on other systems, such as comparable-mass quasicircular inspirals computed by high-accuracy numerical relativistic simulations. C1 [Yunes, Nicolas] Penn State Univ, Dept Phys, Inst Gravitat Phys & Geometry, University Pk, PA 16802 USA. [Yunes, Nicolas] Penn State Univ, Dept Phys, Ctr Gravitat Wave Phys, University Pk, PA 16802 USA. [Berti, Emanuele] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Yunes, N (reprint author), Penn State Univ, Dept Phys, Inst Gravitat Phys & Geometry, 104 Davey Lab, University Pk, PA 16802 USA. RI Berti, Emanuele/C-9331-2016 OI Berti, Emanuele/0000-0003-0751-5130 NR 46 TC 35 Z9 35 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD JUN PY 2008 VL 77 IS 12 AR 124006 DI 10.1103/PhysRevD.77.124006 PG 16 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 321FR UT WOS:000257290600066 ER PT J AU Duggento, A Luchinsky, DG Smelyanskiy, VN Khovanov, I McClintock, PVE AF Duggento, Andrea Luchinsky, Dmitri G. Smelyanskiy, Vadim N. Khovanov, Igor McClintock, Peter V. E. TI Inferential framework for nonstationary dynamics. II. Application to a model of physiological signaling SO PHYSICAL REVIEW E LA English DT Article ID CARDIOVASCULAR-SYSTEM; NERVE; BIFURCATION; INTERFACES; EQUATIONS; COMPUTER AB The problem of how to reconstruct the parameters of a stochastic nonlinear dynamical system when they are time-varying is considered in the context of online decoding of physiological information from neuron signaling activity. To model the spiking of neurons, a set of FitzHugh-Nagumo (FHN) oscillators is used. It is assumed that only a fast dynamical variable can be detected for each neuron, and that the monitored signals are mixed by an unknown measurement matrix. The Bayesian framework introduced in paper I (immediately preceding this paper) is applied both for reconstruction of the model parameters and elements of the measurement matrix, and for inference of the time-varying parameters in the nonstationary system. It is shown that the proposed approach is able to reconstruct unmeasured (hidden) slow variables of the FHN oscillators, to learn to model each individual neuron, and to track continuous, random, and stepwise variations of the control parameter for each neuron in real time. C1 [Duggento, Andrea; Luchinsky, Dmitri G.; Khovanov, Igor; McClintock, Peter V. E.] Univ Lancaster, Dept Phys, Lancaster LA1 4YB, England. [Luchinsky, Dmitri G.; Smelyanskiy, Vadim N.] NASA, Ames Res Ctr, Moffett Field, Moffett Field, CA 94035 USA. [Luchinsky, Dmitri G.] Mission Crit Technol Inc, El Segundo, CA 90245 USA. RP Duggento, A (reprint author), Univ Lancaster, Dept Phys, Lancaster LA1 4YB, England. RI Duggento, Andrea/D-2738-2013; Luchinsky, Dmitry/N-4177-2014 OI Duggento, Andrea/0000-0001-6030-5269; NR 22 TC 15 Z9 15 U1 0 U2 6 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1539-3755 J9 PHYS REV E JI Phys. Rev. E PD JUN PY 2008 VL 77 IS 6 AR 061106 DI 10.1103/PhysRevE.77.061106 PN 1 PG 10 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 321EM UT WOS:000257287500016 PM 18643216 ER PT J AU Luchinsky, DG Smelyanskiy, VN Duggento, A McClintock, PVE AF Luchinsky, Dmitri G. Smelyanskiy, Vadim N. Duggento, Andrea McClintock, Peter V. E. TI Inferential framework for nonstationary dynamics. I. Theory SO PHYSICAL REVIEW E LA English DT Article ID MODELS; RECONSTRUCTION; SYSTEMS; EQUATIONS; NOISE AB A general Bayesian framework is introduced for the inference of time-varying parameters in nonstationary, nonlinear, stochastic dynamical systems. Its convergence is discussed. The performance of the method is analyzed in the context of detecting signaling in a system of neurons modeled as FitzHugh-Nagumo (FHN) oscillators. It is assumed that only fast action potentials for each oscillator mixed by an unknown measurement matrix can be detected. It is shown that the proposed approach is able to reconstruct unmeasured (hidden) variables of the FHN oscillators, to determine the model parameters, to detect stepwise changes of control parameters for each oscillator, and to follow continuous evolution of the control parameters in the adiabatic limit. C1 [Luchinsky, Dmitri G.; Smelyanskiy, Vadim N.] NASA, Ames Res Ctr, Moffett Field, Moffett Field, CA 94035 USA. [Luchinsky, Dmitri G.; Duggento, Andrea; McClintock, Peter V. E.] Univ Lancaster, Dept Phys, Lancaster LA1 4YB, England. RP Luchinsky, DG (reprint author), NASA, Ames Res Ctr, Moffett Field, Mail Stop 269-2, Moffett Field, CA 94035 USA. RI Duggento, Andrea/D-2738-2013; Luchinsky, Dmitry/N-4177-2014 OI Duggento, Andrea/0000-0001-6030-5269; NR 35 TC 13 Z9 13 U1 0 U2 5 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1539-3755 J9 PHYS REV E JI Phys. Rev. E PD JUN PY 2008 VL 77 IS 6 AR 061105 DI 10.1103/PhysRevE.77.061105 PN 1 PG 8 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 321EM UT WOS:000257287500015 PM 18643215 ER PT J AU Lorenz, RD Lopes, RM Paganelli, F Lunine, JI Kirk, RL Mitchell, KL Soderblom, LA Stofan, ER Ori, G Myers, M Miyamoto, H Radebaugh, J Stiles, B Wall, SD Wood, CA AF Lorenz, Ralph D. Lopes, Rosaly M. Paganelli, Flora Lunine, Jonathan I. Kirk, Randolph L. Mitchell, Karl L. Soderblom, Lawrence A. Stofan, Ellen R. Ori, Gian Myers, Melissa Miyamoto, Hideyaki Radebaugh, Jani Stiles, Bryan Wall, Stephen D. Wood, C. A. CA Cassini RADAR Team TI Fluvial channels on Titan: Initial Cassini RADAR observations SO PLANETARY AND SPACE SCIENCE LA English DT Article DE Titan; meteorology; fluvial networks; radar ID RIVER INCISION; HUYGENS PROBE; CLOUDS; SURFACE; ATMOSPHERE; SEDIMENT; DYNAMICS; BEDROCK; RAIN; MARS AB Cassini radar images show a variety of fluvial channels on Titan's surface, often several hundreds of kilometers in length. Some (predominantly at low- and mid-latitude) are radar-bright and braided, resembling desert washes where fines have been removed by energetic surface liquid flow, presumably from methane rainstorms. Others (predominantly at high latitudes) are radar-dark and meandering and drain into or connect polar lakes, suggesting slower-moving flow depositing fine-grained sediments. A third type, seen predominantly at mid- and high latitudes, have radar brightness patterns indicating topographic incision, with valley widths of up to 3 km across and depth of several hundred meters. These observations show that fluvial activity occurs at least occasionally at all latitudes, not only at the Huygens landing site, and can produce channels much larger in scale than those observed there. The areas in which channels are prominent so far amount to about 1% of Titan's surface, of which only a fraction is actually occupied by channels. The corresponding global sediment volume inferred is not enough to account for the extensive sand seas. Channels observed so far have a consistent large-scale flow pattern, tending to flow polewards and eastwards. (C) 2008 Published by Elsevier Ltd. C1 [Lorenz, Ralph D.; Lunine, Jonathan I.; Myers, Melissa] Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. [Lopes, Rosaly M.; Paganelli, Flora; Mitchell, Karl L.; Stiles, Bryan; Wall, Stephen D.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Kirk, Randolph L.; Soderblom, Lawrence A.] US Geol Survey, Flagstaff, AZ 86001 USA. [Stofan, Ellen R.] Proxemy Res, Rectortown, VA 20140 USA. [Ori, Gian] Univ Annunzio, Int Res Sch Planetary Sci, I-65127 Pescara, Italy. [Miyamoto, Hideyaki] Univ Tokyo, Dept Geosyst Engn, Tokyo, Japan. [Radebaugh, Jani] Brigham Young Univ, Dept Geol Sci, Provo, UT 84602 USA. [Wood, C. A.] Planetary Sci Inst, Tucson, AZ 85719 USA. [Wood, C. A.] Wheeling Jesuit Coll, Wheeling, WV 26003 USA. RP Lorenz, RD (reprint author), Johns Hopkins Univ, Appl Phys Lab, Dept Space, Johns Hopkins Rd, Laurel, MD 20723 USA. EM ralph.lorenz@jhuapl.edu RI Miyamoto, Hideaki/B-9666-2008; Miyamoto, Hideaki/E-3381-2012; Lorenz, Ralph/B-8759-2016; Lopes, Rosaly/D-1608-2016; OI Lorenz, Ralph/0000-0001-8528-4644; Lopes, Rosaly/0000-0002-7928-3167; ORI, Gian Gabriele/0000-0002-6460-1476 NR 60 TC 80 Z9 81 U1 1 U2 9 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0032-0633 J9 PLANET SPACE SCI JI Planet Space Sci. PD JUN PY 2008 VL 56 IS 8 BP 1132 EP 1144 DI 10.1016/j.pss.2008.02.009 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 325ZM UT WOS:000257627700006 ER PT J AU Kota, AK Kerzner, R Bigio, DI Bruck, HA Powell, D AF Kota, Arun K. Kerzner, Rachel Bigio, David I. Bruck, Hugh A. Powell, Dan TI Characterization of processing effects in HIPS-CNF composites using thermogravi metric analysis SO POLYMER ENGINEERING AND SCIENCE LA English DT Article ID CARBON NANOTUBES; NANOCOMPOSITES; NANOPARTICLES; FABRICATION; EPOXY AB To completely establish the processing-structure-property relationships of polymer composites such as Carbon Nanofibers (CNFs) in high-impact polystyrene, it is necessary to understand the effects of different processes and processing conditions on the properties of the composites. In this work, using thermogravimetric analysis, the effects of solvent processing and twin-screw extrusion on the weight loss rates and the corresponding temperatures were studied. While there were only marginal effects of the CNF concentration, the type of processing significantly affected the thermo-oxidative behavior. Extrusion resulted in composites that had better thermal stability compared to the solvent processed ones. Furthermore, higher shear rates in extrusion also led to composites with higher thermal stability. This has important implications in choosing the appropriate process and processing conditions for producing polymer-CNF composites. It was also demonstrated that thermogravimetric analysis can provide a means of characterizing the degree of dispersion resulting from the processing of the composites that complements conventional microscopy techniques. C1 [Kota, Arun K.; Kerzner, Rachel; Bigio, David I.; Bruck, Hugh A.] Univ Maryland, Dept Mech Engn, College Pk, MD 20742 USA. [Powell, Dan] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Bruck, HA (reprint author), Univ Maryland, Dept Mech Engn, College Pk, MD 20742 USA. EM bruck@umd.edu NR 19 TC 1 Z9 1 U1 1 U2 2 PU JOHN WILEY & SONS INC PI HOBOKEN PA 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0032-3888 J9 POLYM ENG SCI JI Polym. Eng. Sci. PD JUN PY 2008 VL 48 IS 6 BP 1120 EP 1125 DI 10.1002/pen.21059 PG 6 WC Engineering, Chemical; Polymer Science SC Engineering; Polymer Science GA 307KD UT WOS:000256316900010 ER PT J AU Bandstra, ER Pecaut, MJ Anderson, ER Willey, JS De Carlo, F Stock, SR Gridley, DS Nelson, GA Levine, HG Bateman, TA AF Bandstra, Eric R. Pecaut, Michael J. Anderson, Erica R. Willey, Jeffrey S. De Carlo, Francesco Stock, Stuart R. Gridley, Daila S. Nelson, Gregory A. Levine, Howard G. Bateman, Ted A. TI Long-term dose response of trabecular bone in mice to proton radiation SO RADIATION RESEARCH LA English DT Article ID MICROCOMPUTED TOMOGRAPHY; SYNCHROTRON-RADIATION; DURATION SPACEFLIGHT; GAMMA-IRRADIATION; CARBON ION; CANCER; MOUSE; CELLS; MODEL; ARCHITECTURE AB Astronauts on exploratory missions will experience a complex environment, including microgravity and radiation. While the deleterious effects of unloading on bone are well established, fewer studies have focused on the effects of radiation. We previously demonstrated that 2 Gy of ionizing radiation has deleterious effects on trabecular bone in mice 4 months after exposure. The present study investigated the skeletal response after total doses of proton radiation that astronauts may be exposed to during a solar particle event. We exposed mice to 0.5, 1 or 2 Gy of whole-body proton radiation and killed them humanely 117 days later. Tibiae and femora were analyzed using microcomputed tomography, mechanical testing, mineral composition and quantitative histomorphometry. Relative to control mice, mice exposed to 2 Gy had significant differences in trabecular bone volume fraction (-20%), trabecular separation (+11%), and trabecular volumetric bone mineral density (-19%). Exposure to 1 Gy radiation induced a nonsignificant trend in trabecular bone volume fraction (-13%), while exposure to 0.5 Gy resulted in no differences. No response was detected in cortical bone. Further analysis of the 1-Gy mice using synchrotron microCT revealed a significantly lower trabecular bone volume fraction (-13%) than in control mice. Trabecular bone loss 4 months after exposure to 1 Gy highlights the importance of further examination of how space radiation affects bone. (C) 2008 by Radiation Research Society C1 [Bandstra, Eric R.; Anderson, Erica R.; Willey, Jeffrey S.; Bateman, Ted A.] Clemson Univ, Rhodes Res Ctr 501, Dept Bioengn, Clemson, SC 29631 USA. [Pecaut, Michael J.; Gridley, Daila S.; Nelson, Gregory A.] Loma Linda Univ, Radiat Dept, Loma Linda, CA 92350 USA. [Pecaut, Michael J.; Gridley, Daila S.; Nelson, Gregory A.] Loma Linda Univ, Med Ctr, Loma Linda, CA USA. [De Carlo, Francesco] Argonne Natl Lab, Adv Photon Source, XOR, Argonne, IL 60439 USA. [Stock, Stuart R.] Northwestern Univ, Feinberg Sch Med, Dept Biol Chem & Mol Pharmacol, Chicago, IL 60611 USA. [Levine, Howard G.] NASA, Sustainable Syst Div, Kennedy Space Ctr, FL USA. RP Bateman, TA (reprint author), Clemson Univ, Rhodes Res Ctr 501, Dept Bioengn, Clemson, SC 29631 USA. EM bateman@clemson.edu RI Pecaut, Michael/P-6481-2015; Gridley, Daila/P-7711-2015 OI Pecaut, Michael/0000-0002-2915-9686; FU NIAMS NIH HHS [R21 AR054889] NR 40 TC 24 Z9 25 U1 0 U2 1 PU RADIATION RESEARCH SOC PI LAWRENCE PA 810 E TENTH STREET, LAWRENCE, KS 66044 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD JUN PY 2008 VL 169 IS 6 BP 607 EP 614 DI 10.1667/RR1310.1 PG 8 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA 305LJ UT WOS:000256179600001 PM 18494551 ER PT J AU Mosca, HO Bozzolo, G Garces, JE AF Mosca, H. O. Bozzolo, G. Garces, J. E. TI Site preference, size effects and segregation in RuAlB alloys SO SCRIPTA MATERIALIA LA English DT Article DE modeling; intermetallic compounds; lattice defects; segregation; site preference AB The atomistic modeling of site preference, size effects and segregation behavior of boron additions to RuAl is performed using a quantum approximate method based on first-principles parameterization. The energetics of the site preference behzavior are linked to the explanation of the observed size effects. The dependence of the equilibrium lattice parameter and bulk modulus on B concentration is also shown. (c) 2008 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. C1 [Bozzolo, G.] Ohio Aerosp Inst, Cleveland, OH 44142 USA. [Mosca, H. O.] UA Fis, Comis Nacl Energia Atom, San Martin, Argentina. [Bozzolo, G.] NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. [Garces, J. E.] Comis Nacl Energia Atom, Ctr Atom Bariloche, RA-8400 San Carlos De Bariloche, Rio Negro, Argentina. RP Bozzolo, G (reprint author), Ohio Aerosp Inst, 22800 Cedar Point Rd, Cleveland, OH 44142 USA. EM GuillermoBozzolo@oai.org NR 7 TC 5 Z9 6 U1 1 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6462 J9 SCRIPTA MATER JI Scr. Mater. PD JUN PY 2008 VL 58 IS 11 BP 1025 EP 1028 DI 10.1016/j.scriptamat.2008.01.034 PG 4 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 297FD UT WOS:000255601600024 ER PT J AU Kandula, M Freeman, R AF Kandula, M. Freeman, R. TI On the interaction and coalescence of spherical blast waves SO SHOCK WAVES LA English DT Article DE spherical blast waves; blast wave interaction; measurements on interacting blast waves ID SIMILARITY AB The scaling and similarity laws concerning the propagation of isolated spherical blast waves are briefly reviewed. Both point source explosions and high pressure gas explosions are considered. Test data on blast overpressure from the interaction and coalescence of spherical blast waves emanating from explosives in the form of shaped charges of different strength placed in the vicinity of a solid propellant stack are presented. These data are discussed with regard to the scaling laws concerning the decay of blast overpressure. The results point out the possibility of detecting source explosions from far-field pressure measurements. C1 [Kandula, M.] ASRC Aerosp, Subject Matter Expert, Kennedy Space Ctr, Merritt Isl, FL 32899 USA. NASA, Launch Serv Program, Merritt Isl, FL 32899 USA. RP Kandula, M (reprint author), ASRC Aerosp, Subject Matter Expert, Kennedy Space Ctr, Mail Stop ASRC 5211, Merritt Isl, FL 32899 USA. EM max.kandula-1@ksc.nasa.gov NR 44 TC 4 Z9 5 U1 2 U2 6 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0938-1287 EI 1432-2153 J9 SHOCK WAVES JI Shock Waves PD JUN PY 2008 VL 18 IS 1 BP 21 EP 33 DI 10.1007/s00193-008-0134-1 PG 13 WC Mechanics SC Mechanics GA 312IJ UT WOS:000256662600003 ER PT J AU Rabenhorst, MC Ming, DW Morris, RV Golden, DC AF Rabenhorst, Martin C. Ming, Douglas W. Morris, Richard V. Golden, D. C. TI Synthesized iron oxides used as a tool for documenting reducing conditions in soils SO SOIL SCIENCE LA English DT Article DE wetlands; hydric soils; redox; goethite; ferrihydrite ID REDUCTION; INDICATOR; IRIS AB Recently, a new technology known as indicator of reduction in soils (IRIS) has emerged for documenting reducing conditions in soils. An iron (Fe) oxide paint is applied to polyvinyl chloride tubing that is subsequently placed within the soil. Under reducing conditions, the Fe oxides gain electrons, become soluble, and are stripped from the tubing. This study was initiated to address two questions that have emerged regarding the manufacture and use of IRIS tubes: (i) Why is a mixture of goethite (Gt) and ferrihydrite (minimum 30%-40% Gt) required for the Fe oxide paint to adhere and remain durable when applied to polyvinyl chloride tubing? and (ii) What is represented by the development of pale yellow areas that sometimes are observed on the IRIS tubes? To address these questions, Fe oxide coatings were examined using X-ray diffraction and Mossbauer techniques, by differential chemical extractions, and using scanning electron microscopy. Based on X-ray diffraction and scanning electron microscopy, we conclude that the transformation of ferrihydrite to Gt during paint synthesis results in large Gt crystals with an elongated lath-shaped habit that appear to produce an interlocking network of particles that enhances the durability of the paint. Differential extractions and Mossbauer data indicate that the development of pale yellow zones on the IRIS tubes represents a preferential dissolution of ferrihydrite over Gt, which is consistent with thermodynamic predictions of the relative stability of these two minerals in wetland soil environments. C1 [Rabenhorst, Martin C.] Univ Maryland, College Pk, MD 20742 USA. [Ming, Douglas W.; Morris, Richard V.; Golden, D. C.] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Rabenhorst, MC (reprint author), Univ Maryland, College Pk, MD 20742 USA. EM mrabenho@umd.edu NR 9 TC 3 Z9 3 U1 0 U2 13 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0038-075X J9 SOIL SCI JI Soil Sci. PD JUN PY 2008 VL 173 IS 6 BP 417 EP 423 DI 10.1097/SS.0b013e31817751b17 PG 7 WC Soil Science SC Agriculture GA 315RM UT WOS:000256897100007 ER PT J AU Tsuneta, S Ichimoto, K Katsukawa, Y Nagata, S Otsubo, M Shimizu, T Suematsu, Y Nakagiri, M Noguchi, M Tarbell, T Title, A Shine, R Rosenberg, W Hoffmann, C Jurcevich, B Kushner, G Levay, M Lites, B Elmore, D Matsushita, T Kawaguchi, N Saito, H Mikami, I Hill, LD Owens, JK AF Tsuneta, S. Ichimoto, K. Katsukawa, Y. Nagata, S. Otsubo, M. Shimizu, T. Suematsu, Y. Nakagiri, M. Noguchi, M. Tarbell, T. Title, A. Shine, R. Rosenberg, W. Hoffmann, C. Jurcevich, B. Kushner, G. Levay, M. Lites, B. Elmore, D. Matsushita, T. Kawaguchi, N. Saito, H. Mikami, I. Hill, L. D. Owens, J. K. TI The Solar Optical Telescope for the Hinode mission: An overview SO SOLAR PHYSICS LA English DT Article DE Solar-B; Hinode; Sun : magnetic fields; Sun : photosphere; Sun : chromosphere; Sun : MHD ID MAGNETIC-STRUCTURE; CORONA; HELIOSEISMOLOGY; CHROMOSPHERE; OSCILLATIONS; SIMULATIONS; PHOTOSPHERE; RESOLUTION; SPICULES; DYNAMICS AB The Solar Optical Telescope (SOT) aboard the Hinode satellite (formerly called Solar-B) consists of the Optical Telescope Assembly (OTA) and the Focal Plane Package (FPP). The OTA is a 50-cm diffraction-limited Gregorian telescope, and the FPP includes the narrowband filtergraph (NFI) and the broadband filtergraph (BFI), plus the Stokes Spectro-Polarimeter (SP). The SOT provides unprecedented high-resolution photometric and vector magnetic images of the photosphere and chromosphere with a very stable point spread function and is equipped with an image-stabilization system with performance better than 0.01 arcsec rms. Together with the other two instruments on Hinode (the X-Ray Telescope (XRT) and the EUV Imaging Spectrometer (EIS)), the SOT is poised to address many fundamental questions about solar magnetohydrodynamics. This paper provides an overview; the details of the instrument are presented in a series of companion papers. C1 [Tsuneta, S.; Ichimoto, K.; Katsukawa, Y.; Nagata, S.; Otsubo, M.; Shimizu, T.; Suematsu, Y.; Nakagiri, M.; Noguchi, M.] Natl Astron Observ Japan, Tokyo 1818588, Japan. [Tarbell, T.; Title, A.; Shine, R.; Rosenberg, W.; Hoffmann, C.; Jurcevich, B.; Kushner, G.; Levay, M.] Lockheed Martin Solar & Astrophys Lab, Palo Alto, CA 94304 USA. [Lites, B.; Elmore, D.] Natl Ctr Atmospher Res, High Altitude Observ, Boulder, CO 80307 USA. [Matsushita, T.; Kawaguchi, N.; Saito, H.; Mikami, I.] Mitsubishi Electr Corp, Commun Syst Ctr, Amagasaki, Hyogo 6618661, Japan. [Hill, L. D.; Owens, J. K.] NASA, George C Marshall Space Flight Ctr, Space Sci Off, VP62, Huntsville, AL 35812 USA. RP Tsuneta, S (reprint author), Natl Astron Observ Japan, Tokyo 1818588, Japan. EM saku.tsuneta@nao.ac.jp NR 45 TC 725 Z9 729 U1 2 U2 34 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-0938 J9 SOL PHYS JI Sol. Phys. PD JUN PY 2008 VL 249 IS 2 BP 167 EP 196 DI 10.1007/s11207-008-9174-z PG 30 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 304AV UT WOS:000256083300002 ER PT J AU Reiner, MJ Klein, KL Karlicky, M Jiricka, K Klassen, A Kaiser, ML Bougeret, JL AF Reiner, M. J. Klein, K. -L. Karlicky, M. Jiricka, K. Klassen, A. Kaiser, M. L. Bougeret, J. -L. TI Solar origin of the radio attributes of a complex type III burst observed on 11 April 2001 SO SOLAR PHYSICS LA English DT Article DE solar radio emissions; solar activity; coronal mass ejections ID CORONAL MASS EJECTIONS; ELECTRON EVENTS; PLASMA EJECTION; RAY EVENT; FLARES; SIGNATURES; EMISSION; MHZ; RECONNECTION; CONTINUUM AB We report here on the solar origin of distinctive radiation characteristics observed for a decametric type III solar radio burst that was associated with a major solar flare and CME on 11 April 2001. The associated decimeter (Ondrejov) and meter (Potsdam) wavelength emissions, as well as the GOES soft X-ray lightcurve, suggest that there were two successive events of energy release and electron acceleration associated with this solar eruption. The Nancay radioheliograph images and additional evidence of plasmoid propagation suggest that the second event of electron acceleration resulted from coronal reconfigurations, likely caused by the erupting CME. These observational analyses provide new insights into the physical origin of the distinguishing characteristics of complex type III-like radio emissions that are typically observed at decameter wavelengths during major solar eruptive events. C1 [Reiner, M. J.] Catholic Univ Amer, Greenbelt, MD USA. [Kaiser, M. L.] NASA, Goddard Space Flight Ctr, Space Weather Lab, Greenbelt, MD 20771 USA. [Klein, K. -L.; Bougeret, J. -L.] Observ Paris, CNRS, LESIA, UMR8109, F-92195 Meudon, France. [Karlicky, M.; Jiricka, K.] Acad Sci Czech Republic, Inst Astron, CS-25165 Ondrejov, Czech Republic. [Klassen, A.] Univ Kiel, IEAP, Kiel, Germany. RP Reiner, MJ (reprint author), Catholic Univ Amer, Code 674, Greenbelt, MD USA. EM michael.reiner@nasa.gov RI Karlicky, Marian/G-9023-2014 NR 43 TC 8 Z9 8 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-0938 J9 SOL PHYS JI Sol. Phys. PD JUN PY 2008 VL 249 IS 2 BP 337 EP 354 DI 10.1007/s11207-008-9189-5 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 304AV UT WOS:000256083300011 ER PT J AU Zarka, P Farrell, W Fischer, G Konovalenko, A AF Zarka, P. Farrell, W. Fischer, G. Konovalenko, A. TI Ground-based and space-based radio observations of planetary lightning SO SPACE SCIENCE REVIEWS LA English DT Review DE planetary lightning; planetary atmospheres; atmospheric electricity; planetary ionospheres; radioastronomy; radio emission; radio wave propagation ID SATURN ELECTROSTATIC DISCHARGES; MARTIAN DUST STORMS; VENUS; MARS; IONOSPHERE; ATMOSPHERE; EMISSION; SIGNALS; WAVES; TITAN AB We review radio detection of planetary lightning performed by Voyager, Galileo (including in-situ probe measurements), Cassini, and other spacecraft, and compare the information on the underlying physics derived from these observations-especially the discharge duration, at Jupiter and Saturn-with our knowledge of terrestrial lightning. The controversial evidence at Venus is discussed, as well as the prospects for lightning-like discharges in Martian dust-storms (and studies on terrestrial analogues). In addition, lightning sources provide radio beacons that allow us to probe planetary ionospheres. Ground-based observations of Saturn's lightning have been attempted several times in the past and have been recently successful. They will be the subject of observations by the new generation of giant radio arrays. We review past results and future studies, focussing on the detection challenges and on the interest of ground-based radio monitoring, in conjunction with spacecraft observations or in standalone mode. C1 [Zarka, P.] Univ Paris Diderot, CNRS, Observ Paris, UPMC, F-92190 Meudon, France. [Farrell, W.] NASA Goddard Space Flight Ctr, Sci Explorat Directorate, Greenbelt, MD USA. [Fischer, G.] Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA. [Konovalenko, A.] Natl Acad Sci Ukraine, Inst Radio Astron, UA-61002 Kharkov, SU, Ukraine. RP Zarka, P (reprint author), Univ Paris Diderot, CNRS, Observ Paris, UPMC, 5 Pl Jules Janssen, F-92190 Meudon, France. EM philippe.zarka@obspm.fr RI Farrell, William/I-4865-2013 NR 54 TC 19 Z9 19 U1 0 U2 6 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 J9 SPACE SCI REV JI Space Sci. Rev. PD JUN PY 2008 VL 137 IS 1-4 BP 257 EP 269 DI 10.1007/s11214-008-9366-8 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 338ZD UT WOS:000258547000016 ER PT J AU Fischer, G Gurnett, DA Kurth, WS Akalin, F Zarka, P Dyudina, UA Farrell, WM Kaiser, ML AF Fischer, Georg Gurnett, Donald A. Kurth, William S. Akalin, Ferzan Zarka, Philippe Dyudina, Ulyana A. Farrell, William M. Kaiser, Michael L. TI Atmospheric electricity at Saturn SO SPACE SCIENCE REVIEWS LA English DT Review DE Saturn; lightning; Saturn; atmosphere ID CASSINI IMAGING SCIENCE; RADIO ASTRONOMY OBSERVATIONS; ELECTROSTATIC DISCHARGES; GALILEO IMAGES; SOLAR-SYSTEM; WATER CLOUD; JUPITER; MODEL; IONOSPHERE; THUNDERCLOUD AB The Cassini mission provides a great opportunity to enlarge our knowledge of atmospheric electricity at the gas giant Saturn. Following Voyager studies, the RPWS (Radio and Plasma Wave Science) instrument has measured again the so-called SEDs (Saturn Electrostatic Discharges) which are the radio signature of lightning flashes. Observations by Cassini/ISS (Imaging Science Subsystem) have shown cloud features in Saturn's atmosphere whose occurrence, longitudinal drift rate, and brightness were strongly related to the SEDs. In this paper we will review the main physical parameters of the SEDs. Lightning does not only give us clues about the dynamics of the atmosphere, but also serves as a natural tool to investigate properties of Saturn's ionosphere. We will also discuss other lightning related phenomena and compare Saturn lightning with terrestrial and Jovian lightning. C1 [Fischer, Georg; Gurnett, Donald A.; Kurth, William S.; Akalin, Ferzan] Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA. [Zarka, Philippe] Observ Paris, Meudon, France. [Dyudina, Ulyana A.] CALTECH, Pasadena, CA 91125 USA. [Farrell, William M.; Kaiser, Michael L.] NASA Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Fischer, G (reprint author), Univ Iowa, Dept Phys & Astron, 203 Van Allen Hall, Iowa City, IA 52242 USA. EM georg-fischer@uiowa.edu RI Farrell, William/I-4865-2013; OI Kurth, William/0000-0002-5471-6202 NR 60 TC 25 Z9 25 U1 3 U2 7 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-6308 J9 SPACE SCI REV JI Space Sci. Rev. PD JUN PY 2008 VL 137 IS 1-4 BP 271 EP 285 DI 10.1007/s11214-008-9370-z PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 338ZD UT WOS:000258547000017 ER PT J AU Su, H Jiang, JH Gu, Y Neelin, JD Kahn, BH Feldman, D Yung, YL Waters, JW Livesey, NJ Santee, ML Read, WG AF Su, Hui Jiang, Jonathan H. Gu, Yu Neelin, J. David Kahn, Brian H. Feldman, Daniel Yung, Yuk L. Waters, Joe W. Livesey, Nathaniel J. Santee, Michelle L. Read, William G. TI Variations of tropical upper tropospheric clouds with sea surface temperature and implications for radiative effects SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ADAPTIVE INFRARED IRIS; DEEP CONVECTION; CIRRUS CLOUDS; NO EVIDENCE; ENVIRONMENTAL-CONDITIONS; CLIMATE FEEDBACK; ENERGY-BALANCE; EOS MLS; SATELLITE; EARTH AB The variations of tropical upper tropospheric (UT) clouds with sea surface temperature (SST) are analyzed using effective cloud fraction from the Atmospheric Infrared Sounder (AIRS) on Aqua and ice water content (IWC) from the Microwave Limb Sounder (MLS) on Aura. The analyses are limited to UT clouds above 300 hPa. Our analyses do not suggest a negative correlation of tropical-mean UT cloud fraction with the cloud-weighted SST (CWT). Instead, both tropical-mean UT cloud fraction and IWC are found to increase with CWT, although their correlations with CWT are rather weak. The rate of increase of UT cloud fraction with CWT is comparable to that of precipitation, while the UT IWC and ice water path (IWP) increase more strongly with CWT. The radiative effect of UT clouds is investigated, and they are shown to provide a net warming at the top of the atmosphere. An increase of IWP with SST yields an increase of net warming that corresponds to a positive feedback, until the UT IWP exceeds a value about 50% greater than presently observed by MLS. Further increases of the UT IWP would favor the shortwave cooling effect, causing a negative feedback. Sensitivities of UT cloud forcing to the uncertainties in UT CFR and IWC measurements are discussed. C1 [Su, Hui; Jiang, Jonathan H.; Kahn, Brian H.; Waters, Joe W.; Livesey, Nathaniel J.; Santee, Michelle L.; Read, William G.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Feldman, Daniel; Yung, Yuk L.] CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA. [Gu, Yu; Neelin, J. David] Univ Calif Los Angeles, Dept Atmospher & Ocean Sci, Los Angeles, CA 90095 USA. RP Su, H (reprint author), CALTECH, Jet Prop Lab, M-S 183-701,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM hui.su@jpl.nasa.gov RI Neelin, J. David/H-4337-2011; Feldman, Daniel/N-8703-2013 OI Feldman, Daniel/0000-0003-3365-5233 NR 67 TC 12 Z9 12 U1 2 U2 8 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 31 PY 2008 VL 113 IS D10 AR D10211 DI 10.1029/2007JD009624 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 307ZW UT WOS:000256359100006 ER PT J AU Ader, M Chaudhuri, S Coates, JD Coleman, M AF Ader, Magali Chaudhuri, Swades Coates, John D. Coleman, Max TI Microbial perchlorate reduction: A precise laboratory determination of the chlorine isotope fractionation and its possible biochemical basis SO EARTH AND PLANETARY SCIENCE LETTERS LA English DT Article DE perchlorate; perchlorate reduction; isotope fractionation mechanism; Azospira suillum; chlorine stable isotopes ID SULFATE-REDUCING BACTERIA; (PER)CHLORATE-REDUCING BACTERIA; NATURAL PERCHLORATE; STABLE-ISOTOPES; OXYGEN; CHLORATE; SULFUR; BIODEGRADATION; PURIFICATION; MECHANISM AB Perchlorate-reducing bacteria fractionate chlorine stable isotopes giving a powerful approach to monitor the extent of microbial consumption of perchlorate in contaminated sites undergoing remediation or natural perchlorate containing sites. This study reports the full experimental data and methodology used to re-evaluate the chlorine isotope fractionation of perchlorate reduction in duplicate culture experiments of Azospira suillum strain PS at 37 degrees C (Delta Cl-37(Cr)--ClO4-) previously reported, without a supporting data set by Coleman et al. [Coleman, M.L., Ader, M., Chaudhuri, S., Coates,J.D., 2003. Microbial Isotopic Fractionation of Perchlorate Chlorine. Appl. Environ. Microbiol. 69, 4997-5000] in a reconnaissance study, with the goal of increasing the accuracy and precision of the isotopic fractionation determination. The method fully described here for the first time, allows the determination of a higher precision Delta Cl-37(Cl)--ClO4- value, either from accumulated chloride content and isotopic composition or from the residual perchlorate content and isotopic composition. The result sets agree perfectly, within error, giving average Delta Cl-37(Cl)--ClO4- = -14.94 +/- 0.15%omicron. Complementary use of chloride and perchlorate data allowed the identification and rejection of poor quality data by applying mass and isotopic balance checks. This precise Delta Cl-37(Cl)--ClO4-, value can serve as a reference point for comparison with future in situ or microcosm studies but we also note its similarity to the theoretical equilibrium isotopic fractionation between a hypothetical chlorine species of redox state +6 and perchlorate at 37 degrees C and suggest that the first electron transfer during perchlorate reduction may occur at isotopic equilibrium between art enzyme-bound chlorine and perchlorate. (C) 2008 Elsevier B.V. All rights reserved. C1 [Coleman, Max] Jet Prop Lab, Caltech, CA USA. [Ader, Magali] Univ Paris 07, F-75221 Paris 05, France. [Ader, Magali] Inst Phys Globe, Paris, France. [Ader, Magali; Coleman, Max] Univ Reading, Sch Human & Environm Sci, Reading, Berks, England. [Chaudhuri, Swades] Texas A&M Univ, Dept Chem Engn, College Stn, TX 77843 USA. [Chaudhuri, Swades; Coates, John D.] Univ Calif Berkeley, Dept Plant & Microbial Biol, Berkeley, CA 94720 USA. RP Coleman, M (reprint author), Jet Prop Lab, Caltech, CA USA. EM max.coleman@jpl.nasa.gov RI Coleman, Max/A-1303-2007; ader, magali/A-5613-2011 OI Coleman, Max/0000-0002-5514-1826; ader, magali/0000-0002-9239-1509 NR 54 TC 4 Z9 6 U1 2 U2 19 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0012-821X J9 EARTH PLANET SC LETT JI Earth Planet. Sci. Lett. PD MAY 30 PY 2008 VL 269 IS 3-4 BP 604 EP 612 DI 10.1016/j.epsl.2008.03.023 PG 9 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 312YX UT WOS:000256709400030 ER PT J AU Chandler, MO Avanov, LA Craven, PD Mozer, FS Moore, TE AF Chandler, Michael O. Avanov, Levon A. Craven, Paul D. Mozer, F. S. Moore, T. E. TI Observations of the ion signatures of double merging and the formation of newly closed field lines SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID INTERPLANETARY MAGNETIC-FIELD; LATITUDE BOUNDARY-LAYER; RECONNECTION; MAGNETOPAUSE; MODEL; CUSP; MAGNETOSPHERE; SIMULATION; FLOW AB Observations from the Thermal Ion Dynamics Experiment (TIDE) on the Polar spacecraft, taken during a period of northward interplanetary magnetic field (IMF) show magnetosheath ions within the magnetosphere with velocity distributions resulting from two widely separated (similar to 30 R(E)) merging sites along the same field lines. These results are consistent with the hypothesis that double merging can produce closed field lines populated by solar wind plasma under northward IMF. While the merging sites cannot be unambiguously located, the directions of the flowing magnetosheath populations and the convection of merged field lines are consistent with locations of two merging sites northward of the spacecraft and the analyses favor one site poleward of the northern cusp and a second site at lower latitudes equatorward of the northern cusp. C1 [Chandler, Michael O.; Craven, Paul D.] NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35805 USA. [Avanov, Levon A.] Univ Alabama, Huntsville, AL 35805 USA. [Moore, T. E.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Mozer, F. S.] Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. RP Chandler, MO (reprint author), NASA, George C Marshall Space Flight Ctr, 320 Sparkman Dr, Huntsville, AL 35805 USA. EM michael.o.chandler@nasa.gov RI Moore, Thomas/D-4675-2012 OI Moore, Thomas/0000-0002-3150-1137 NR 28 TC 3 Z9 3 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAY 30 PY 2008 VL 35 IS 10 AR L10107 DI 10.1029/2008GL033910 PG 6 WC Geosciences, Multidisciplinary SC Geology GA 307ZJ UT WOS:000256357800004 ER PT J AU Kirk, BS Carey, GF AF Kirk, Benjamin S. Carey, Graham F. TI Development and validation of a SUPG finite element scheme for the compressible Navier-Stokes equations using a modified inviscid flux discretization SO INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS LA English DT Article DE SUPG; finite element; compressible flows; shock capturing; inviscid flux discretization; validation ID ADVECTIVE-DIFFUSIVE SYSTEMS; EULER EQUATIONS; FORMULATION; DYNAMICS; ALGORITHM; OPERATOR; FLOWS AB This paper considers the streamline-upwind Petrov-Galerkin (SUPG) method applied to the unsteady compressible Navier-Stokes equations in conservation-variable form. The spatial discretization, including a modified approach for interpolating the inviscid flux terms in the SUPG finite element formulation, and the second-order accurate time discretization are presented. The numerical method is discussed in detail. The performance of the algorithm is then investigated by considering inviscid flow past a circular cylinder. Validation of the finite element formulation via comparisons with experimental data for high-Mach number perfect gas laminar flows is presented, with a specific focus on comparisons with experimentally measured skin friction and convective heat transfer on a 15 degrees compression ramp. Copyright (C) 2007 John Wiley & Sons, Ltd. C1 [Kirk, Benjamin S.; Carey, Graham F.] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. [Kirk, Benjamin S.; Carey, Graham F.] Univ Texas Austin, Austin, TX 78712 USA. RP Kirk, BS (reprint author), NASA, Lyndon B Johnson Space Ctr, Mail Code EG3,2101 NASA Pkwy, Houston, TX 77058 USA. EM benjamin.kirk@nasa.gov NR 46 TC 8 Z9 10 U1 0 U2 5 PU JOHN WILEY & SONS LTD PI CHICHESTER PA THE ATRIUM, SOUTHERN GATE, CHICHESTER PO19 8SQ, W SUSSEX, ENGLAND SN 0271-2091 J9 INT J NUMER METH FL JI Int. J. Numer. Methods Fluids PD MAY 30 PY 2008 VL 57 IS 3 BP 265 EP 293 DI 10.1002/fld.1635 PG 29 WC Computer Science, Interdisciplinary Applications; Mathematics, Interdisciplinary Applications; Mechanics; Physics, Fluids & Plasmas SC Computer Science; Mathematics; Mechanics; Physics GA 299BX UT WOS:000255731900002 ER PT J AU Echer, E Gonzalez, WD Tsurutani, BT Gonzalez, ALC AF Echer, E. Gonzalez, W. D. Tsurutani, B. T. Gonzalez, A. L. C. TI Interplanetary conditions causing intense geomagnetic storms (Dst <=-100 nT) during solar cycle 23 (1996-2006) SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID SOLAR-WIND; MAGNETIC STORMS; INTERACTION REGIONS; BOUNDARY-LAYER; JANUARY 1997; ORIGIN; CYCLE; FIELD; SUBSTORM; CLOUD AB [1] The interplanetary causes of intense geomagnetic storms and their solar dependence occurring during solar cycle 23 (1996-2006) are identified. During this solar cycle, all intense (Dst <= -100 nT) geomagnetic storms are found to occur when the interplanetary magnetic field was southwardly directed (in GSM coordinates) for long durations of time. This implies that the most likely cause of the geomagnetic storms was magnetic reconnection between the southward IMF and magnetopause fields. Out of 90 storm events, none of them occurred during purely northward IMF, purely intense IMF By fields or during purely high speed streams. We have found that the most important interplanetary structures leading to intense southward Bz ( and intense magnetic storms) are magnetic clouds which drove fast shocks (sMC) causing 24% of the storms, sheath fields (Sh) also causing 24% of the storms, combined sheath and MC fields (Sh+MC) causing 16% of the storms, and corotating interaction regions ( CIRs), causing 13% of the storms. These four interplanetary structures are responsible for three quarters of the intense magnetic storms studied. The other interplanetary structures causing geomagnetic storms were: magnetic clouds that did not drive a shock (nsMC), non magnetic clouds ICMEs, complex structures resulting from the interaction of ICMEs, and structures resulting from the interaction of shocks, heliospheric current sheets and high speed stream Alfven waves. During the rising phase of the solar cycle, sMC and sheaths are the dominant structure driving intense storms. At solar maximum, sheath fields, followed by Sh+MCs and then by sMC were responsible for most of the storms. During the declining phase, sMC, Sh and CIR fields are the main interplanetary structures leading to intense storms. We have also observed that around 70% of the storms follow the interplanetary criteria of Ey >= 5 mV/m for at least 3 h. Around 90% of the storms used in the study followed a less stringent set of criteria: Ey >= 3 mV/m for at least 3 h. Finally, we obtain the approximate rate of intense magnetic storms per solar cycle phases: minimum/rising phase 3 storms. year(-1), maximum phase 8.5 storms. year(-1), and declining/minimum phases 6.5 storms. year(-1). C1 [Echer, E.; Gonzalez, W. D.; Gonzalez, A. L. C.] Inst Nacl Pesquisas Espaciais, BR-12227010 Sao Paulo, Brazil. [Tsurutani, B. T.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Echer, E (reprint author), Inst Nacl Pesquisas Espaciais, POB 515,Sao Jose Campos, BR-12227010 Sao Paulo, Brazil. EM eecher@dge.inpe.br NR 44 TC 104 Z9 108 U1 0 U2 9 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAY 30 PY 2008 VL 113 IS A5 AR A05221 DI 10.1029/2007JA012744 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 308AY UT WOS:000256361900001 ER PT J AU Tang, CL Lu, L McKenna-Lawlor, S Barabash, S Liu, ZX Fok, MC Li, ZY AF Tang, C. L. Lu, L. McKenna-Lawlor, S. Barabash, S. Liu, Z. X. Fok, M. -C. Li, Z. Y. TI A comparison of Neutral Atom Detector Unit neutral atom image inversion with a comprehensive ring current model SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID MAGNETIC-FIELD; PLASMA SHEET; DISTRIBUTIONS; SIMULATION; SUBSTORMS; ENA AB We present energetic neutral atom (ENA) images in the energy range 45 to 50 keV for H and 92 to 138 keV for O measured by the Neutral Atom Detector Unit (NUADU) onboard Double Star TC-2 during a geomagnetic storm on 8 May 2005. We compare the ion fluxes deduced from inversion of the NUADU image with those calculated using the Comprehensive Ring Current Model (CRCM). This comparison shows that the two approaches are consistent when used to derive the configuration of the corresponding global ion distribution and the peak ion fluxes. The deduced peak ion flux is located in the premidnight sector at 1540 UT, while the deduced ion peak flux is located in the midnight sector at 1610 UT. There are strong ion fluxes in the region between L = 2 and L = 4 which form a closed loop configuration. The ion peak flux is about 2.2 x 10(6)/cm(2)/sr/keV/s. The deduced ion distribution agrees well with the NUADU measurement. The agreement between the inverted ion distributions and the CRCM results give us confidence in applying our ENA imaging and modeling techniques to the study of the evolution of the inner magnetosphere plasma distribution and the global dynamics of the ring current during magnetic storms. C1 [Tang, C. L.; Li, Z. Y.] Univ Sci & Technol China, Sch Earth & Space Sci, Hefei 230026, Peoples R China. [Lu, L.; Liu, Z. X.] Chinese Acad Sci, Ctr Space Sci & Appl Res, Beijing 100081, Peoples R China. [McKenna-Lawlor, S.] Natl Univ Ireland, Maynooth, Kildare, Ireland. [Barabash, S.] Swedish Inst Space Phys, SE-98128 Kiruna, Sweden. [Fok, M. -C.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Tang, CL (reprint author), Univ Sci & Technol China, Sch Earth & Space Sci, Hefei 230026, Peoples R China. EM tcl@mail.ustc.edu.cn RI Fok, Mei-Ching/D-1626-2012 NR 17 TC 1 Z9 2 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAY 30 PY 2008 VL 113 IS A7 AR A07S32 DI 10.1029/2007JA012680 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 308BC UT WOS:000256362300001 ER PT J AU Phillips, RJ Zuber, MT Smrekar, SE Mellon, MT Head, JW Tanaka, KL Putzig, NE Milkovich, SM Campbell, BA Plaut, JJ Safaeinili, A Seu, R Biccari, D Carter, LM Picardi, G Orosei, R Mohit, PS Heggy, E Zurek, RW Egan, AF Giacomoni, E Russo, F Cutigni, M Pettinelli, E Holt, JW Leuschen, CJ Marinangeli, L AF Phillips, Roger J. Zuber, Maria T. Smrekar, Suzanne E. Mellon, Michael T. Head, James W. Tanaka, Kenneth L. Putzig, Nathaniel E. Milkovich, Sarah M. Campbell, Bruce A. Plaut, Jeffrey J. Safaeinili, Ali Seu, Roberto Biccari, Daniela Carter, Lynn M. Picardi, Giovanni Orosei, Roberto Mohit, P. Surdas Heggy, Essam Zurek, Richard W. Egan, Anthony F. Giacomoni, Emanuele Russo, Federica Cutigni, Marco Pettinelli, Elena Holt, John W. Leuschen, Carl J. Marinangeli, Lucia TI Mars north polar deposits: Stratigraphy, age, and geodynamical response SO SCIENCE LA English DT Article ID LAYERED DEPOSITS; EVOLUTION; REGION; CAP; SUBSURFACE; RHEOLOGY; HISTORY; CRUSTAL; MANTLE AB The Shallow Radar ( SHARAD) on the Mars Reconnaissance Orbiter has imaged the internal stratigraphy of the north polar layered deposits of Mars. Radar reflections within the deposits reveal a laterally continuous deposition of layers, which typically consist of four packets of finely spaced reflectors separated by homogeneous interpacket regions of nearly pure ice. The packet/ interpacket structure can be explained by approximately million- year periodicities in Mars' obliquity or orbital eccentricity. The observed similar to 100- meter maximum deflection of the underlying substrate in response to the ice load implies that the present- day thickness of an equilibrium elastic lithosphere is greater than 300 kilometers. Alternatively, the response to the load may be in a transient state controlled by mantle viscosity. Both scenarios probably require that Mars has a subchondritic abundance of heat- producing elements. C1 [Phillips, Roger J.; Putzig, Nathaniel E.; Egan, Anthony F.] SW Res Inst, Boulder, CO 80302 USA. [Phillips, Roger J.] Washington Univ, St Louis, MO 63130 USA. [Zuber, Maria T.] MIT, Cambridge, MA 02139 USA. [Smrekar, Suzanne E.; Milkovich, Sarah M.; Plaut, Jeffrey J.; Safaeinili, Ali; Zurek, Richard W.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Mellon, Michael T.] Univ Colorado, Boulder, CO 80309 USA. [Head, James W.] Brown Univ, Providence, RI 02912 USA. [Tanaka, Kenneth L.] US Geol Survey, Flagstaff, AZ 86001 USA. [Campbell, Bruce A.; Carter, Lynn M.] Smithsonian Inst, Washington, DC 20013 USA. [Seu, Roberto; Biccari, Daniela; Picardi, Giovanni; Giacomoni, Emanuele; Russo, Federica; Cutigni, Marco] Univ Roma La Sapienza, Dipartimento InfoCom, I-00184 Rome, Italy. [Orosei, Roberto] Ist Nazl Astrofis, I-00133 Rome, Italy. [Mohit, P. Surdas] Univ Calif San Diego, Scripps Inst Oceanog, La Jolla, CA 92093 USA. [Mohit, P. Surdas] Univ British Columbia, Vancouver, BC V6T 1Z4, Canada. [Heggy, Essam] Lunar & Planetary Inst, Houston, TX 77058 USA. [Heggy, Essam] Inst Phys Globe, Paris, France. [Pettinelli, Elena] Univ Roma Tre, I-00146 Rome, Italy. [Holt, John W.] Univ Texas Austin, Jackson Sch Geosci, Austin, TX 78712 USA. [Leuschen, Carl J.] Univ Kansas, Lawrence, KS 66045 USA. [Marinangeli, Lucia] Univ Annunzio, I-65127 Pescara, Italy. RP Phillips, RJ (reprint author), SW Res Inst, Boulder, CO 80302 USA. EM roger@boulder.swri.edu RI Holt, John/C-4896-2009; Carter, Lynn/D-2937-2012; Heggy, Essam/E-8250-2013; Mellon, Michael/C-3456-2016; OI Heggy, Essam/0000-0001-7476-2735; PETTINELLI, Elena/0000-0002-7066-6516 NR 34 TC 140 Z9 140 U1 4 U2 26 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD MAY 30 PY 2008 VL 320 IS 5880 BP 1182 EP 1185 DI 10.1126/science.1157546 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 306FF UT WOS:000256233000029 PM 18483402 ER PT J AU Peters-Lidard, CD Mocko, DM Garcia, M Santanello, JA Tischler, MA Moran, MS Wu, YH AF Peters-Lidard, Christa D. Mocko, David M. Garcia, Matthew Santanello, Joseph A., Jr. Tischler, Michael A. Moran, M. Susan Wu, Yihua TI Role of precipitation uncertainty in the estimation of hydrologic soil properties using remotely sensed soil moisture in a semiarid environment SO WATER RESOURCES RESEARCH LA English DT Article ID LAND-SURFACE MODEL; BOUNDARY-LAYER; PEDOTRANSFER FUNCTIONS; HYDRAULIC-PROPERTIES; DATA ASSIMILATION; MONSOON 90; ETA-MODEL; WATER; SIMULATION; PARAMETERIZATION AB The focus of this study is on the role of precipitation uncertainty in the estimation of soil texture and soil hydraulic properties for application to land-atmosphere modeling systems. This work extends a recent study by Santanello et al. (2007) in which it was shown that soil texture and related physical parameters may be estimated using a combination of multitemporal microwave remote sensing, land surface modeling, and parameter estimation methods. As in the previous study, the NASA-GSFC Land Information System modeling framework, including the community Noah land surface model constrained with pedotransfer functions (PTF) for use with the Parameter Estimation Tool, is applied to several sites in the Walnut Gulch Experimental Watershed (WGEW) in southeastern Arizona during the Monsoon '90 experiment period. It is demonstrated that the application of PTF constraints in the estimation process for hydraulic parameters provides accuracy similar to direct hydrologic parameter estimation, with the additional benefit of simultaneously estimated soil texture. Precipitation uncertainty is then represented with systematically varying sources, from the high-density precipitation gauge network in WGEW to lower quality sources, including spatially averaged precipitation, single gauges in and near the watershed, and results from the continental-scale North American Regional Reanalysis data set. It is demonstrated that the quality of the input precipitation data set, and particularly the accuracy of the data set, in both detection of convective ( heavy) rainfall events and reproduction of the observed rainfall rate probabilities, is a critical determinant in the use of successive remote sensing results in order to establish and refine estimates of soil texture and hydraulic properties. C1 [Peters-Lidard, Christa D.; Mocko, David M.; Garcia, Matthew; Santanello, Joseph A., Jr.; Wu, Yihua] NASA, Goddard Space Flight Ctr, Hydrol Sci Branch, Greenbelt, MD 20771 USA. [Mocko, David M.] NASA, Goddard Space Flight Ctr, Climate & Radiat Branch, Greenbelt, MD 20771 USA. [Mocko, David M.] Sci Applicat Int Corp, Beltsville, MD USA. [Garcia, Matthew; Wu, Yihua] Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. [Santanello, Joseph A., Jr.] Univ Maryland, Earth Syst Sci Interdisciplinary Ctr, College Pk, MD 20742 USA. [Tischler, Michael A.] USA, Corps Engineers, Ctr Res Dev & Engn, Topograph Engn Ctr, Alexandria, VA 22315 USA. [Moran, M. Susan] USDA ARS, SW Watershed Res Ctr, Tucson, AZ 85719 USA. RP Wu, YH (reprint author), NASA, Goddard Space Flight Ctr, Hydrol Sci Branch, Code 6143, Greenbelt, MD 20771 USA. EM christa.peters@nasa.gov; david.mocko@nasa.gov; matthew.garcia@nasa.gov; joseph.santanello@nasa.gov; michael.a.tischler@erdc.usace.army.mil; smoran@tucson.ars.ag.gov; yihua.wu@noaa.gov RI Santanello, Joseph/D-4438-2012; Garcia, Matthew/K-9286-2013; Peters-Lidard, Christa/E-1429-2012 OI Santanello, Joseph/0000-0002-0807-6590; Garcia, Matthew/0000-0002-9637-4204; Peters-Lidard, Christa/0000-0003-1255-2876 NR 63 TC 19 Z9 21 U1 1 U2 8 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD MAY 30 PY 2008 VL 44 IS 5 AR W05S18 DI 10.1029/2007WR005884 PG 22 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 308BS UT WOS:000256363900001 ER PT J AU Bucsela, EJ Perring, AE Cohen, RC Boersma, KF Celarier, EA Gleason, JF Wenig, MO Bertram, TH Wooldridge, PJ Dirksen, R Veefkind, JP AF Bucsela, E. J. Perring, A. E. Cohen, R. C. Boersma, K. F. Celarier, E. A. Gleason, J. F. Wenig, M. O. Bertram, T. H. Wooldridge, P. J. Dirksen, R. Veefkind, J. P. TI Comparison of tropospheric NO2 from in situ aircraft measurements with near-real-time and standard product data from OMI SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID INDUCED FLUORESCENCE DETECTION; OZONE MONITORING INSTRUMENT; SURFACE REFLECTIVITY; ATMOSPHERIC NO2; NITROGEN; GOME; RETRIEVALS; MODEL; DISTRIBUTIONS; COLUMNS AB We present an analysis of in situ NO2 measurements from aircraft experiments between summer 2004 and spring 2006. The data are from the INTEX-A, PAVE, and INTEX-B campaigns and constitute the most comprehensive set of tropospheric NO2 profiles to date. Profile shapes from INTEX-A and PAVE are found to be qualitatively similar to annual mean profiles from the GEOS-Chem model. Using profiles from the INTEX-B campaign, we perform error-weighted linear regressions to compare the Ozone Monitoring Instrument (OMI) tropospheric NO2 columns from the near-real-time product (NRT) and standard product (SP) with the integrated in situ columns. Results indicate that the OMI SP algorithm yields NO2 amounts lower than the in situ columns by a factor of 0.86 (+/- 0.2) and that NO2 amounts from the NRT algorithm are higher than the in situ data by a factor of 1.68 (+/- 0.6). The correlation between the satellite and in situ data is good (r = 0.83) for both algorithms. Using averaging kernels, the influence of the algorithm's a priori profiles on the satellite retrieval is explored. Results imply that air mass factors from the a priori profiles are on average slightly larger (similar to 10%) than those from the measured profiles, but the differences are not significant. C1 [Bucsela, E. J.] SRI Int, Menlo Pk, CA 94025 USA. [Celarier, E. A.] SGT Inc, Greenbelt, MD 20770 USA. [Wenig, M. O.] City Univ Hong Kong, Dept Phys & Mat Sci, Kowloon, Hong Kong, Peoples R China. [Bucsela, E. J.; Celarier, E. A.; Gleason, J. F.; Wenig, M. O.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Boersma, K. F.; Dirksen, R.; Veefkind, J. P.] Royal Netherlands Meteorol Inst, NL-3730 AE De Bilt, Netherlands. [Perring, A. E.; Cohen, R. C.; Bertram, T. H.; Wooldridge, P. J.] Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. [Bucsela, E. J.; Wenig, M. O.] Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21201 USA. RP Bucsela, EJ (reprint author), SRI Int, 333 Ravenswood Ave, Menlo Pk, CA 94025 USA. EM bucsela@ix.netcom.com RI Cohen, Ronald/A-8842-2011; Gleason, James/E-1421-2012; Boersma, Klaas/H-4559-2012; Wenig, Mark/K-7279-2012; Perring, Anne/G-4597-2013; Chem, GEOS/C-5595-2014 OI Cohen, Ronald/0000-0001-6617-7691; Boersma, Klaas/0000-0002-4591-7635; Perring, Anne/0000-0003-2231-7503; NR 39 TC 60 Z9 63 U1 0 U2 17 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 29 PY 2008 VL 113 IS D16 AR D16S31 DI 10.1029/2007JD008838 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 307ZY UT WOS:000256359300002 ER PT J AU Considine, DB Natarajan, M Fairlie, TD Lingenfelser, GS Pierce, RB Froidevaux, L Lambert, A AF Considine, D. B. Natarajan, M. Fairlie, T. D. Lingenfelser, G. S. Pierce, R. B. Froidevaux, L. Lambert, A. TI Noncoincident validation of Aura MLS observations using the Langley Research Center Lagrangian chemistry and transport model SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID HALOGEN OCCULTATION EXPERIMENT; STRATOSPHERE; PROFILES; UARS; HCL; HF AB We evaluate Aura Microwave Limb Sounder version 2.2 measurements of O-3, HCl, and H2O with version 19 HALOE observations using a model-assisted, noncoincident intercomparison technique. Air parcels in the Langley Research Center Lagrangian chemistry and transport model (LCTM) are initialized from HALOE observations made during three different 3-week periods in 2004 and early 2005. The LCTM tracks the dynamical and photochemical evolution of the ensemble of air parcels following initialization. We show that the LCTM predictions agree closely with subsequent HALOE measurements not used to initialize the model, demonstrating the model's capability to accurately propagate information from the HALOE observations. HALOE-initialized LCTM O-3 predictions agree very well in the stratosphere with MLS measurements, with coincident zonal mean differences generally less than 10%. We find low biases in HCl of 10 -30% relative to the MLS observations. We also find low biases with respect to MLS H2O of up to 15% in the upper and middle stratosphere and similar to 30% low biases in the lower stratosphere/upper troposphere midlatitudes. We note some nonphysical vertical oscillations of MLS H2O in the tropical and midlatitude lower stratosphere that are not present in the HALOE-initialized LCTM output. The oscillations are smaller in version 2.2 than in previous versions. These results are generally consistent with published HALOE/ MLS intercomparisons of these species using a traditional coincident validation technique. This consistency suggests that the traditional coincident validation results are applicable on daily temporal and zonal spatial scales. C1 [Considine, D. B.; Natarajan, M.; Fairlie, T. D.; Pierce, R. B.] NASA, Langley Res Ctr, Hampton, VA 23681 USA. [Lingenfelser, G. S.] Sci Syst & Applicat Int Inc, Hampton, VA 23681 USA. [Froidevaux, L.; Lambert, A.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Considine, DB (reprint author), NASA, Langley Res Ctr, Hampton, VA 23681 USA. EM david.b.considine@nasa.gov RI Pierce, Robert Bradley/F-5609-2010 OI Pierce, Robert Bradley/0000-0002-2767-1643 NR 23 TC 4 Z9 4 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 29 PY 2008 VL 113 IS D16 AR D16S33 DI 10.1029/2007JD008770 PG 19 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 307ZY UT WOS:000256359300001 ER PT J AU Dong, XQ Wielicki, BA Xi, BK Hu, Y Mace, GG Benson, S Rose, F Kato, S Charlock, T Minnis, P AF Dong, Xiquan Wielicki, Bruce A. Xi, Baike Hu, Yongxiang Mace, Gerald G. Benson, Sally Rose, Fred Kato, Seiji Charlock, Thomas Minnis, Patrick TI Using observations of deep convective systems to constrain atmospheric column absorption of solar radiation in the optically thick limit SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SHORTWAVE EXPERIMENT ARESE; ANGULAR-DISTRIBUTION MODELS; MEASURING MISSION SATELLITE; CLOUD PROPERTIES; AIRCRAFT MEASUREMENTS; FLUX ESTIMATION; SURFACE; MODIS; CERES; REFLECTANCE AB Atmospheric column absorption of solar radiation (A(col)) is a fundamental part of the Earth's energy cycle but is an extremely difficult quantity to measure directly. To investigate Acol, we have collocated satellite-surface observations for the optically thick Deep Convective Systems (DCS) at the Department of Energy Atmosphere Radiation Measurement (ARM) Tropical Western Pacific (TWP) and Southern Great Plains (SGP) sites during the period of March 2000-December 2004. The surface data were averaged over a 2-h interval centered at the time of the satellite overpass, and the satellite data were averaged within a 1 degrees x 1 degrees area centered on the ARM sites. In the DCS, cloud particle size is important for top-of-atmosphere (TOA) albedo and Acol although the surface absorption is independent of cloud particle size. In this study, we find that the Acol in the tropics is similar to 0.011 more than that in the middle latitudes. This difference, however, disappears, i.e., the Acol values at both regions converge to the same value (similar to 0.27 of the total incoming solar radiation) in the optically thick limit (tau > 80). Comparing the observations with the NASA Langley modified Fu_Liou 2-stream radiative transfer model for optically thick cases, the difference between observed and model-calculated surface absorption, on average, is less than 0.01, but the model-calculated TOA albedo and Acol differ by 0.01 to 0.04, depending primarily on the cloud particle size observation used. The model versus observation discrepancies found are smaller than many previous studies and are just within the estimated error bounds. We did not find evidence for a large cloud absorption anomaly for the optically thick limit of extensive ice cloud layers. A more modest cloud absorption difference of 0.01 to 0.04 cannot yet be ruled out. The remaining uncertainty could be reduced with additional cases, and by reducing the current uncertainty in cloud particle size. C1 [Dong, Xiquan; Xi, Baike] Univ N Dakota, Dept Atmospher Sci, Grand Forks, ND 58202 USA. [Wielicki, Bruce A.; Hu, Yongxiang; Kato, Seiji; Charlock, Thomas; Minnis, Patrick] NASA, Langley Res Ctr, Hampton, VA 23681 USA. [Mace, Gerald G.; Benson, Sally] Univ Utah, Dept Meteorol, Salt Lake City, UT 84112 USA. [Rose, Fred] SSAI, Hampton, VA 23666 USA. RP Dong, XQ (reprint author), Univ N Dakota, Dept Atmospher Sci, 4149 Univ Dt Stop 9006, Grand Forks, ND 58202 USA. EM dong@aero.und.edu RI Hu, Yongxiang/K-4426-2012; Minnis, Patrick/G-1902-2010; OI Rose, Fred G/0000-0003-0769-0772; Minnis, Patrick/0000-0002-4733-6148; Dong, Xiquan/0000-0002-3359-6117 NR 47 TC 11 Z9 11 U1 1 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 29 PY 2008 VL 113 IS D10 AR D10206 DI 10.1029/2007JD009769 PG 18 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 307ZU UT WOS:000256358900005 ER PT J AU Stajner, I Wargan, K Pawson, S Hayashi, H Chang, LP Hudman, RC Froidevaux, L Livesey, N Levelt, PF Thompson, AM Tarasick, DW Stubi, R Andersen, SB Yela, M Konig-Langlo, G Schmidlin, FJ Witte, JC AF Stajner, Ivanka Wargan, Krzysztof Pawson, Steven Hayashi, Hiroo Chang, Lang-Ping Hudman, Rynda C. Froidevaux, Lucien Livesey, Nathaniel Levelt, Pieternel F. Thompson, Anne M. Tarasick, David W. Stuebi, Rene Andersen, Signe Bech Yela, Margarita Koenig-Langlo, Gert Schmidlin, F. J. Witte, Jacquelyn C. TI Assimilated ozone from EOS-Aura: Evaluation of the tropopause region and tropospheric columns SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID MOZAIC AIRBORNE PROGRAM; SATELLITE-OBSERVATIONS; MONITORING INSTRUMENT; TRANSPORT MODEL; TROPICAL OZONE; SYSTEM; CHEMISTRY; MLS; VARIABILITY; O-3 AB Retrievals from the Microwave Limb Sounder (MLS) and the Ozone Monitoring Instrument (OMI) on EOS-Aura were included in the Goddard Earth Observing System version 4 (GEOS-4) ozone data assimilation system. The distribution and daily to seasonal evolution of ozone in the stratosphere and troposphere during 2005 are investigated. In the lower stratosphere, where dynamical processes dominate, comparisons with independent ozonesonde and Measurement of Ozone and Water Vapour by Airbus In-Service Aircraft (MOZAIC) data indicate mean agreement within 10%. In the troposphere, OMI and MLS provide constraints on the ozone column, but the ozone profile shape results from the parameterized ozone chemistry and the resolved and parameterized transport. Assimilation of OMI and MLS data improves tropospheric column estimates in the Atlantic region but leads to an overestimation in the tropical Pacific and an underestimation in the northern high and middle latitudes in winter and spring. Transport and data biases are considered in order to understand these discrepancies. Comparisons of assimilated tropospheric ozone columns with ozonesonde data reveal root-mean-square (RMS) differences of 2.9-7.2 Dobson units (DU), which are smaller than the model-sonde RMS differences of 3.2-8.7 DU. Four different definitions of the tropopause using temperature lapse rate, potential vorticity (PV), and isentropic surfaces or ozone isosurfaces are compared with respect to their global impact on the estimated tropospheric ozone column. The largest sensitivity in the tropospheric ozone column is found near the subtropical jet, where the ozone-or PV-determined tropopause typically lies below the lapse rate tropopause. C1 [Yela, Margarita] Inst Nacl Techn Aerospacial, E-28850 Madrid, Spain. [Witte, Jacquelyn C.] Sci Syst & Applicat Inc, Lanham, MD 20706 USA. [Thompson, Anne M.] Penn State Univ, Dept Meteorol, University Pk, PA 16802 USA. [Tarasick, David W.] Environm Canada, Air Qual Res Div, Downsview, ON M3H 5T4, Canada. [Stuebi, Rene] MeteoSwiss, Aerol Stn Payerne, CH-1530 Payerne, Switzerland. [Schmidlin, F. J.] NASA, Goddard Space Flight Ctr, Wallops Flight Facil, Wallops Isl, VA 23337 USA. [Stajner, Ivanka; Wargan, Krzysztof; Pawson, Steven; Hayashi, Hiroo; Chang, Lang-Ping] NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Greenbelt, MD 20771 USA. [Levelt, Pieternel F.] Royal Dutch Meteorol Inst, NL-3730 AE De Bilt, Netherlands. [Koenig-Langlo, Gert] Alfred Wegener Inst Polar & Marine Res, D-27515 Bremerhaven, Germany. [Hudman, Rynda C.] Harvard Univ, Atmospher Chem Modeling Grp, Cambridge, MA 02138 USA. [Hayashi, Hiroo] Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. [Froidevaux, Lucien; Livesey, Nathaniel] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Stajner, Ivanka; Wargan, Krzysztof; Chang, Lang-Ping] Sci Applicat Int Corp, Beltsville, MD 20705 USA. [Andersen, Signe Bech] Danish Meteorol Inst, DK-2100 Copenhagen, Denmark. RP Stajner, I (reprint author), Noblis Inc, 3150 Fairview Pk Dr S,MS F540, Falls Church, VA 22042 USA. EM ivanka.stajner@noblis.org RI Hudman, Rynda/C-6118-2009; andersen, signe/C-4809-2013; Stajner, Ivanka/B-5228-2009; Konig-Langlo, Gert/K-5048-2012; Yela, Margarita/J-7346-2016; Pawson, Steven/I-1865-2014; Thompson, Anne /C-3649-2014; OI andersen, signe/0000-0002-8216-0141; Wargan, Krzysztof/0000-0002-3795-2983; Stajner, Ivanka/0000-0001-6103-3939; Konig-Langlo, Gert/0000-0002-6100-4107; Yela, Margarita/0000-0003-3775-3156; Pawson, Steven/0000-0003-0200-717X; Thompson, Anne /0000-0002-7829-0920; Tarasick, David/0000-0001-9869-0692 NR 61 TC 45 Z9 46 U1 1 U2 12 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 29 PY 2008 VL 113 IS D16 AR D16S32 DI 10.1029/2007JD008863 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 307ZY UT WOS:000256359300003 ER PT J AU McSween, HY Ruff, SW Morris, RV Gellert, R Klingelhofer, G Christensen, PR Mccoy, TJ Ghosh, A Moersch, JM Cohen, BA Rogers, AD Schroder, C Squyres, SW Crisp, J Yen, A AF McSween, H. Y. Ruff, S. W. Morris, R. V. Gellert, R. Klingelhoefer, G. Christensen, P. R. McCoy, T. J. Ghosh, A. Moersch, J. M. Cohen, B. A. Rogers, A. D. Schroeder, C. Squyres, S. W. Crisp, J. Yen, A. TI Mineralogy of volcanic rocks in Gusev Crater, Mars: Reconciling Mossbauer, Alpha Particle X-ray Spectrometer, and Miniature Thermal Emission Spectrometer spectra SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID MERIDIANI-PLANUM; SPIRIT ROVER; SURFACE; PATHFINDER; CHEMISTRY; ORIGIN; DUST; SITE AB Complete sets of mineral abundances for relatively unaltered volcanic or volcaniclastic rocks in Gusev Crater have been determined by modeling Mossbauer subspectral areas as mineral weight percentages, and combining those percentages with the proportions of iron-free minerals not detected by Mossbauer (normative plagioclase, apatite, and chromite, as calculated from Alpha Particle X-Ray Spectrometer (APXS) chemical analyses). Comparisons of synthetic thermal emission spectra calculated for these mineral modes with measured Miniature Thermal Emission Spectrometer (Mini-TES) spectra for the same rock classes show either good agreements or discrepancies that we attribute to sodic plagioclase compositions or unmodeled sulfate, glass, or pigeonite. The normative compositions of olivine, pyroxene, and feldspar calculated from APXS data are consistent with spectroscopic constraints on mineral compositions. Systematic variations between olivine abundances in APXS norms ( which sample tens of micrometers depth) and olivine proportions measured by Mossbauer ( which sample hundreds of micrometers depth) support the hypothesis that dissolution of olivine by acidic fluids has occurred on weathered rock surfaces. C1 [McSween, H. Y.; Ghosh, A.; Moersch, J. M.] Univ Tennessee, Dept Earth & Planetary Sci, Knoxville, TN 37996 USA. [Ruff, S. W.; Christensen, P. R.] Arizona State Univ, Dept Geol Sci, Tempe, AZ 85287 USA. [Cohen, B. A.] NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. [Crisp, J.; Yen, A.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Gellert, R.] Univ Guelph, Dept Phys, Guelph, ON N1G 2W1, Canada. [Klingelhoefer, G.; Schroeder, C.] Johannes Gutenberg Univ Mainz, Inst Anorgan & Analyt Chem, D-55128 Mainz, Germany. [McCoy, T. J.] Natl Museum Nat Hist, Smithsonian Inst, Washington, DC 20560 USA. [Morris, R. V.] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. [Rogers, A. D.] CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA. [Squyres, S. W.] Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. RP McSween, HY (reprint author), Univ Tennessee, Dept Earth & Planetary Sci, 306 Geol Sci Bldg, Knoxville, TN 37996 USA. EM mcsween@utk.edu RI Schroder, Christian/B-3870-2009; Moersch, Jeffrey/F-7189-2010; Crisp, Joy/H-8287-2016; Rogers, Deanne/I-9737-2016 OI Schroder, Christian/0000-0002-7935-6039; Crisp, Joy/0000-0002-3202-4416; Rogers, Deanne/0000-0002-4671-2551 NR 37 TC 54 Z9 54 U1 0 U2 11 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9097 EI 2169-9100 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD MAY 29 PY 2008 VL 113 IS E6 AR E06S04 DI 10.1029/2007JE002970 PG 14 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 308AO UT WOS:000256360900001 ER PT J AU Seo, BJ Kim, S Fetterman, H Steier, W Jin, D Dinu, R AF Seo, Byoung-Joon Kim, Seongku Fetterman, Harold Steier, William Jin, Dan Dinu, Raluca TI Design of ring resonators using electro-optic polymer waveguides SO JOURNAL OF PHYSICAL CHEMISTRY C LA English DT Article ID MODULATORS; FILTERS AB New developments in optical nonlinear polymers have now enabled the implementation of novel new devices. The most important element of these new devices is usually a coupled ring resonator system that can be tuned with an electric field. In this study we have analyzed the design considerations, for these rings, and show how to determine and optimize all of the critical parameters. In addition, we demonstrate how to make the key characterization tests that confirm the component's performance. All of this is structured so that it can be extended to the newer and higher electro-optic coefficient materials that are currently being fabricated. Future devices using this technology are expected to play a major role in the rapidly expanding field of optical signal processing. C1 [Steier, William] Univ So Calif, Dept Elect Engn, Los Angeles, CA 90089 USA. [Jin, Dan; Dinu, Raluca] Lumera Corp, Bothell, WA 98011 USA. [Seo, Byoung-Joon; Kim, Seongku; Fetterman, Harold] Univ Calif Los Angeles, Dept Elect Engn, Los Angeles, CA 90095 USA. RP Seo, BJ (reprint author), Jet Prop Lab, Pasadena, CA 91109 USA. NR 19 TC 17 Z9 17 U1 2 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1932-7447 J9 J PHYS CHEM C JI J. Phys. Chem. C PD MAY 29 PY 2008 VL 112 IS 21 BP 7953 EP 7958 DI 10.1021/jp711914a PG 6 WC Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary SC Chemistry; Science & Technology - Other Topics; Materials Science GA 304HF UT WOS:000256099900024 ER PT J AU Wachter, S Ramirez-Ruiz, E Dwarkadas, VV Kouveliotou, C Granot, J Patel, SK Figer, D AF Wachter, S. Ramirez-Ruiz, E. Dwarkadas, V. V. Kouveliotou, C. Granot, J. Patel, S. K. Figer, D. TI An infrared ring around the magnetar SGR 1900+14 SO NATURE LA English DT Article ID GAMMA-RAY BURSTS; SGR 1900+14; STARS; DISCOVERY; PULSAR; DUST; SGR-1806-20; CLUSTER AB Magnetars(1,2) are a special class of slowly rotating ( period similar to 5 - 12 s) neutron stars with extremely strong magnetic fields (>10(14) G) - at least an order of magnitude larger than those of the 'normal' radio pulsars. The potential evolutionary links and differences between these two types of object are still unknown; recent studies, however, have provided circumstantial evidence connecting magnetars with very massive progenitor stars(3-5). Here we report the discovery of an infrared elliptical ring or shell surrounding the magnetar SGR 1900+14. The appearance and energetics of the ring are difficult to interpret within the framework of the progenitor's stellar mass loss or the subsequent evolution of the supernova remnant. We suggest instead that a dust- free cavity was produced in the magnetar environment by the giant flare emitted by the source in August 1998. Considering the total energy released in the flare, the theoretical dust- destruction radius matches well with the observed dimensions of the ring. We conclude that SGR 1900+14 is unambiguously associated with a cluster of massive stars, thereby solidifying the link between magnetars and massive stars. C1 [Wachter, S.] CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA. [Dwarkadas, V. V.] Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. [Kouveliotou, C.] NASA, George C Marshall Space Flight Ctr, NSSTC, Huntsville, AL 35805 USA. [Granot, J.] Univ Hertfordshire, Ctr Astrophys Res, Hatfield AL10 9AB, Herts, England. [Patel, S. K.] Opt Sci Corp, Huntsville, AL 35806 USA. [Figer, D.] Rochester Inst Technol, Chester F Carlson Ctr Imaging Sci, Rochester, NY 14623 USA. RP Wachter, S (reprint author), CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA. EM wachter@ipac.caltech.edu NR 30 TC 11 Z9 11 U1 1 U2 2 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 EI 1476-4687 J9 NATURE JI Nature PD MAY 29 PY 2008 VL 453 IS 7195 BP 626 EP 628 DI 10.1038/nature06987 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 305NN UT WOS:000256185200037 PM 18509437 ER PT J AU Chen, WT Kahn, RA Nelson, D Yau, K Seinfeld, JH AF Chen, Wei-Ting Kahn, Ralph A. Nelson, David Yau, Kevin Seinfeld, John H. TI Sensitivity of multiangle imaging to the optical and microphysical properties of biomass burning aerosols SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SINGLE-SCATTERING ALBEDO; BLACK CARBON CONTENT; SOUTHERN AFRICA; SAFARI 2000; PHYSICAL-PROPERTIES; LIGHT-ABSORPTION; SIZE DISTRIBUTIONS; SMOKE PARTICLES; SUN PHOTOMETERS; SKY RADIANCE AB The treatment of biomass burning (BB) carbonaceous particles in the Multiangle Imaging SpectroRadiometer (MISR) Standard Aerosol Retrieval Algorithm is assessed, and algorithm refinements are suggested, based on a theoretical sensitivity analysis and comparisons with near-coincident AERONET measurements at representative BB sites. Over the natural ranges of BB aerosol microphysical and optical properties observed in past field campaigns, patterns of retrieved Aerosol Optical Depth (AOD), particle size, and single scattering albedo (SSA) are evaluated. On the basis of the theoretical analysis, assuming total column AOD of 0.2, over a dark, uniform surface, MISR can distinguish two to three groups in each of size and SSA, except when the assumed atmospheric particles are significantly absorbing (mid-visible SSA similar to 0.84), or of medium sizes ( mean radius similar to 0.13 mu m); sensitivity to absorbing, medium-large size particles increases considerably when the assumed column AOD is raised to 0.5. MISR Research Aerosol Retrievals confirm the theoretical results, based on coincident AERONET inversions under BB-dominated conditions. When BB is externally mixed with dust in the atmosphere, dust optical model and surface reflection uncertainties, along with spatial variability, contribute to differences between the Research Retrievals and AERONET. These results suggest specific refinements to the MISR Standard Aerosol Algorithm complement of component particles and mixtures. They also highlight the importance for satellite aerosol retrievals of surface reflectance characterization, with accuracies that can be difficult to achieve with coupled surface-aerosol algorithms in some higher AOD situations. C1 [Chen, Wei-Ting] CALTECH, Dept Environm Sci & Engn, Pasadena, CA 91125 USA. [Kahn, Ralph A.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Nelson, David; Yau, Kevin] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Seinfeld, John H.] CALTECH, Dept Chem Engn, Pasadena, CA 91125 USA. RP Chen, WT (reprint author), CALTECH, Dept Environm Sci & Engn, 1200 E Calif Blvd,Mail Code 210-41, Pasadena, CA 91125 USA. EM seinfield@caltech.edu RI Kahn, Ralph/D-5371-2012; Chen, Wei-Ting/A-4476-2012 OI Kahn, Ralph/0000-0002-5234-6359; Chen, Wei-Ting/0000-0002-9292-0933 NR 66 TC 33 Z9 33 U1 0 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 28 PY 2008 VL 113 IS D10 AR D10203 DI 10.1029/2007JD009414 PG 22 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 307ZS UT WOS:000256358700007 ER PT J AU Wichansky, PS Steyaert, LT Walko, RL Weaver, CP AF Wichansky, Paul S. Steyaert, Louis T. Walko, Robert L. Weaver, Christopher P. TI Evaluating the effects of historical land cover change on summertime weather and climate in New Jersey: Land cover and surface energy budget changes SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Review ID URBAN HEAT-ISLAND; SCALE ATMOSPHERIC PROCESSES; CONTERMINOUS UNITED-STATES; CONVECTIVE BOUNDARY-LAYER; GENERAL-CIRCULATION MODEL; DIURNAL TEMPERATURE-RANGE; SOUTHERN GREAT-PLAINS; MESOSCALE CIRCULATIONS; AGRICULTURAL LAND; GLOBAL CLIMATE AB The 19th-century agrarian landscape of New Jersey (NJ) and the surrounding region has been extensively transformed to the present-day land cover by urbanization, reforestation, and localized areas of deforestation. This study used a mesoscale atmospheric numerical model to investigate the sensitivity of the warm season climate of NJ to these land cover changes. Reconstructed 1880s-era and present-day land cover data sets were used as surface boundary conditions for a set of simulations performed with the Regional Atmospheric Modeling System (RAMS). Three-member ensembles with historical and present-day land cover were compared to examine the sensitivity of surface air and dew point temperatures, rainfall, and the individual components of the surface energy budget to these land cover changes. Mean temperatures for the present-day landscape were 0.3-0.6 degrees C warmer than for the historical landscape over a considerable portion of NJ and the surrounding region, with daily maximum temperatures at least 1.0 degrees C warmer over some of the highly urbanized locations. Reforested regions, however, were slightly cooler. Dew point temperatures decreased by 0.3-0.6 degrees C, suggesting drier, less humid near-surface air for the present-day landscape. Surface warming was generally associated with repartitioning of net radiation from latent to sensible heat flux, and conversely for cooling. While urbanization was accompanied by strong surface albedo decreases and increases in net shortwave radiation, reforestation and potential changes in forest composition have generally increased albedos and also enhanced landscape heterogeneity. The increased deciduousness of forests may have further reduced net downward longwave radiation. C1 [Wichansky, Paul S.; Weaver, Christopher P.] Rutgers State Univ, Ctr Environm Predict, New Brunswick, NJ 08901 USA. [Wichansky, Paul S.; Weaver, Christopher P.] Rutgers State Univ, Dept Environm Sci, New Brunswick, NJ 08901 USA. [Steyaert, Louis T.] NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Greenbelt, MD 20771 USA. [Steyaert, Louis T.] US Geol Survey, Ctr Earth Resources Observat & Sci, Greenbelt, MD 20771 USA. [Walko, Robert L.] Duke Univ, Dept Civil & Environm Engn, Durham, NC 27706 USA. RP Wichansky, PS (reprint author), Rutgers State Univ, Ctr Environm Predict, New Brunswick, NJ 08901 USA. EM pstuart@cep.rutgers.edu RI Weaver, Christopher/G-3714-2010 OI Weaver, Christopher/0000-0003-4016-5451 NR 130 TC 8 Z9 8 U1 1 U2 18 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 28 PY 2008 VL 113 IS D10 AR D10107 DI 10.1029/2007JD008514 PG 25 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 307ZS UT WOS:000256358700001 ER PT J AU Shreiber, D Gupta, M Cravey, R AF Shreiber, D. Gupta, M. Cravey, R. TI Microwave nondestructive evaluation of dielectric materials with a metamaterial lens SO SENSORS AND ACTUATORS A-PHYSICAL LA English DT Article DE negative index of refraction; metamaterial lens; sub-wavelength focusing; microwave NDE; near field imaging ID REFRACTION; INDEX AB A novel microwave nondestructive evaluation (NDE) sensor was developed in an attempt to increase the sensitivity of the microwave NDE method for detection of defects small relative to a wavelength. The sensor was designed on the basis of a negative index material (NIM) lens. Characterization of the lens was performed to determine its resonant frequency, index of refraction, focus spot size, and optimal focusing length (for proper sample location). A sub-wavelength spot size (3 dB) of 0.48 lambda was obtained. The proof of concept for the sensor was achieved when a fiberglass sample with a 3 mm diameter through hole (perpendicular to the propagation direction of the wave) was tested. The hole was successfully detected with an 8.2 cm wavelength electromagnetic wave. This method is able to detect a defect that is 0.037 lambda. This method has certain advantages over other far field and near field microwave NDE methods currently in use. (C) 2008 Elsevier B.V. All rights reserved. C1 [Shreiber, D.; Gupta, M.] Univ Virginia, Dept Elect & Comp Engn, Charlottesville, VA 22904 USA. [Cravey, R.] NASA, Langley Res Ctr, Electromagnet & Sensors Branch, Hampton, VA 23681 USA. RP Gupta, M (reprint author), Univ Virginia, Dept Elect & Comp Engn, Charlottesville, VA 22904 USA. EM mgupta@virginia.edu OI Shreiber, David/0000-0001-8248-419X NR 13 TC 8 Z9 8 U1 1 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0924-4247 J9 SENSOR ACTUAT A-PHYS JI Sens. Actuator A-Phys. PD MAY 28 PY 2008 VL 144 IS 1 BP 48 EP 55 DI 10.1016/j.sna.2007.12.031 PG 8 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 302TU UT WOS:000255993200007 ER PT J AU Brown, SR Toberer, ES Ikeda, T Cox, CA Gascoin, F Kauzlarich, SM Snyder, GJ AF Brown, Shawna R. Toberer, Eric S. Ikeda, Teruyuki Cox, Catherine A. Gascoin, Franck Kauzlarich, Susan M. Snyder, G. Jeffrey TI Improved thermoelectric performance in Yb14Mn1-xZnxSb11 by the reduction of spin-disorder scattering SO CHEMISTRY OF MATERIALS LA English DT Article ID ZINTL COMPOUNDS; RARE-EARTH; YB14MNSB11; ANTIMONIDES; YB14ZNSB11; YB AB Rare-earth transition metal compounds Yb14Mn1-xZnxSb11, isostructural with Ca14AlSb11, have been prepared using a metal flux growth technique for thermoelectric property measurements (with x = 0.0, 0.2, 0.3, 0.4, 0.7, 0.9, and 1.0). Single-crystal X-ray diffraction and electron microprobe analysis data indicate the successful synthesis of a solid-solution for the Yb14Mn1-xZnxSb11 structure type for 0 < x < 0.4. Hot-pressed polycrystalline samples showed that the product from the flux reaction was a pure phase from x = 0 through x = 0.4 with the presence of a minor secondary phase for compositions x > 0.4. High-temperature (298 K-1275 K) measurements of the Seebeck coefficient, resistivity, and thermal conductivity were performed on hot-pressed, polycrystalline samples. As the concentration of Zn increases in Yb14Mn1-xZnxSb11, the Seebeck coefficient remains unchanged for 0 <= x <= 0.7 indicating that the free carrier concentration has remained unchanged. However, as the nonmagnetic Zn2+ ions replace the magnetic Mn2+ ions, the spin disorder scattering is reduced, lowering the resistivity. Replacing the magnetic Mn2+ with non magnetic Zn2+ provides an independent means to lower resistivity without deleterious effects to the Seebeck values or thermal conduction. Alloying the Mn site with Zn reduces the lattice thermal conductivity at low temperatures but has negligible impact at high temperatures. The reduction of spin disorder scattering leads to an similar to 10% improvement over Yb14MnSb11, revealing a maximum thermoelectric figure of merit (zT) of similar to 1.1 at 1275 K for Yb14Mn0.6Zn0.4Sb11. C1 [Brown, Shawna R.; Cox, Catherine A.; Kauzlarich, Susan M.] Univ Calif Davis, Dept Chem, Davis, CA 95616 USA. [Toberer, Eric S.; Ikeda, Teruyuki; Gascoin, Franck; Snyder, G. Jeffrey] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Gascoin, Franck; Snyder, G. Jeffrey] CALTECH, Pasadena, CA 91125 USA. RP Kauzlarich, SM (reprint author), Univ Calif Davis, Dept Chem, 1 Shields Ave, Davis, CA 95616 USA. EM smkauzlarich@ucdavis.edu; jsnyder@caltech.edu RI Kauzlarich, Susan/H-1439-2011; Snyder, G. Jeffrey/E-4453-2011; Ikeda, Teruyuki/J-6176-2014; Snyder, G/I-2263-2015 OI Snyder, G. Jeffrey/0000-0003-1414-8682; Ikeda, Teruyuki/0000-0001-7076-6958; NR 30 TC 76 Z9 76 U1 4 U2 28 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0897-4756 J9 CHEM MATER JI Chem. Mat. PD MAY 27 PY 2008 VL 20 IS 10 BP 3412 EP 3419 DI 10.1021/cm703616q PG 8 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 303QW UT WOS:000256056600024 ER PT J AU Aragao, LEOC Malhi, Y Barbier, N Lima, A Shimabukuro, Y Anderson, L Saatchi, S AF Aragao, Luiz Eduardo O. C. Malhi, Yadvinder Barbier, Nicolas Lima, Andre Shimabukuro, Yosio Anderson, Liana Saatchi, Sassan TI Interactions between rainfall, deforestation and fires during recent years in the Brazilian Amazonia SO PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES LA English DT Article DE Amazonia; fire; deforestation; drought; land use; climate change ID TROPICAL FORESTS; CLIMATE-CHANGE; POSITIVE FEEDBACKS; EASTERN AMAZON; VARIABILITY; BASIN; SCALE; SUSCEPTIBILITY; PRECIPITATION; RESPONSES AB Understanding the interplay between climate and land-use dynamics is a fundamental concern for assessing the vulnerability of Amazonia to climate change. In this study, we analyse satellite-derived monthly and annual time series of rainfall, fires and deforestation to explicitly quantify the seasonal patterns and relationships between these three variables, with a particular focus on the Amazonian drought of 2005. Our results demonstrate a marked seasonality with one peak per year for all variables analysed, except deforestation. For the annual cycle, we found correlations above 90% with a time lag between variables. Deforestation and fires reach the highest values three and six months, respectively, after the peak of the rainy season. The cumulative number of hot pixels was linearly related to the size of the area deforested annually from 1998 to 2004 (r(2)=0.84, p=0.004). During the 2005 drought, the number of hot pixels increased 43% in relation to the expected value for a similar deforested area (approx. 19 000 km(2)). We demonstrated that anthropogenic forcing, such as land-use change, is decisive in determining the seasonality and annual patterns of fire occurrence. Moreover, droughts can significantly increase the number of fires in the region even with decreased deforestation rates. We may expect that the ongoing deforestation, currently based on slash and burn procedures, and the use of fires for land management in Amazonia will intensify the impact of droughts associated with natural climate variability or human-induced climate change and, therefore, a large area of forest edge will be under increased risk of fires. C1 [Aragao, Luiz Eduardo O. C.; Malhi, Yadvinder; Barbier, Nicolas; Anderson, Liana] Univ Oxford, Environm Change Inst, Ctr Environm, Oxford OX1 3QY, England. [Barbier, Nicolas] Univ Libre Brussels, Serv Botan Systemat & Phytophysiol, B-1050 Brussels, Belgium. [Lima, Andre; Shimabukuro, Yosio] Brazilian Inst Space Res, BR-12227 Sao Paulo, Brazil. [Saatchi, Sassan] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Aragao, LEOC (reprint author), Univ Oxford, Environm Change Inst, Ctr Environm, Oxford OX1 3QY, England. EM leocaragao@gmail.com RI Barbier, Nicolas/A-5489-2010; aragao, luiz/G-8387-2012; Anderson, Liana/G-8389-2012 OI Barbier, Nicolas/0000-0002-5323-3866; aragao, luiz/0000-0002-4134-6708; Anderson, Liana/0000-0001-9545-5136 NR 43 TC 119 Z9 121 U1 2 U2 38 PU ROYAL SOC PI LONDON PA 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 0962-8436 EI 1471-2970 J9 PHILOS T R SOC B JI Philos. Trans. R. Soc. B-Biol. Sci. PD MAY 27 PY 2008 VL 363 IS 1498 BP 1779 EP 1785 DI 10.1098/rstb.2007.0026 PG 7 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 282OQ UT WOS:000254577500009 PM 18267907 ER PT J AU Bush, MB Silman, MR McMichael, C Saatchi, S AF Bush, M. B. Silman, M. R. McMichael, C. Saatchi, S. TI Fire, climate change and biodiversity in Amazonia: a Late-Holocene perspective SO PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES LA English DT Article DE neotropical; charcoal; fire; migration; solar minimum; warming ID ARCHAEOLOGICAL EVIDENCE; BRAZILIAN AMAZONIA; ATLANTIC CLIMATE; SOIL CHARCOAL; RAIN-FORESTS; HISTORY; TREE; CONSERVATION; OSCILLATION; CALIBRATION AB Fire is an important and arguably unnatural component of many wet Amazonian and Andean forest systems. Soil charcoal has been used to infer widespread human use of landscapes prior to European Conquest. An analysis of Amazonian soil carbon records reveals that the records have distinct spatial and temporal patterns, suggesting that either fires were only set in moderately seasonal areas of Amazonia or that strongly seasonal and aseasonal areas are undersampled. Synthesizing data from 300 charcoal records, an age-frequency diagram reveals peaks of fire apparently coinciding with some periods of very strong El Nino activity. However, the El Nino record does not always provide an accurate prediction of fire timing, and a better match is found in the record of insolation minima. After the time of European contact, fires became much scarcer within Amazonia. In both the Amazonia and the Andes, modern fire pattern is strongly allied to human activity. On the flank of the Andes, forests that have never burned are being eroded by fire spreading downslope from grasslands. Species of these same forests are being forced to migrate upslope due to warming and will encounter a firm artificial fire boundary of human activity. C1 [Bush, M. B.; McMichael, C.] Florida Inst Technol, Dept Biol Sci, Melbourne, FL 32901 USA. [Silman, M. R.] Wake Forest Univ, Dept Biol, Winston Salem, NC 27104 USA. [Saatchi, S.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Bush, MB (reprint author), Florida Inst Technol, Dept Biol Sci, 150 W Univ Blvd, Melbourne, FL 32901 USA. EM mbush@fit.edu RI Silman, Miles/H-1280-2011 NR 58 TC 62 Z9 64 U1 3 U2 28 PU ROYAL SOC PI LONDON PA 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 0962-8436 J9 PHILOS T R SOC B JI Philos. Trans. R. Soc. B-Biol. Sci. PD MAY 27 PY 2008 VL 363 IS 1498 BP 1795 EP 1802 DI 10.1098/rstb.2007.0014 PG 8 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 282OQ UT WOS:000254577500011 PM 18267914 ER PT J AU Gao, J Daal, M Martinis, JM Vayonakis, A Zmuidzinas, J Sadoulet, B Mazin, BA Day, PK Leduc, HG AF Gao, Jiansong Daal, Miguel Martinis, John M. Vayonakis, Anastasios Zmuidzinas, Jonas Sadoulet, Bernard Mazin, Benjamin A. Day, Peter K. Leduc, Henry G. TI A semiempirical model for two-level system noise in superconducting microresonators SO APPLIED PHYSICS LETTERS LA English DT Article ID KINETIC INDUCTANCE DETECTORS AB We present measurements of the low-temperature excess frequency noise of four niobium superconducting coplanar waveguide microresonators, with center strip widths s(r) ranging from 3 to 20 mu m. For a fixed internal power, we find that the frequency noise decreases rapidly with increasing center strip width, scaling as 1/s(r)(1.6). We show that this geometrical scaling is readily explained by a simple semiempirical model which assumes a surface distribution of independent two-level system fluctuators. These results allow the resonator geometry to be optimized for minimum noise. (c) 2008 American Institute of Physics. C1 [Gao, Jiansong; Vayonakis, Anastasios; Zmuidzinas, Jonas] CALTECH, Div Phys Math & Astron, Pasadena, CA 91125 USA. [Daal, Miguel; Sadoulet, Bernard] Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. [Martinis, John M.] Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA. [Mazin, Benjamin A.; Day, Peter K.; Leduc, Henry G.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Gao, J (reprint author), CALTECH, Div Phys Math & Astron, Pasadena, CA 91125 USA. EM jiansong@caltech.edu RI Mazin, Ben/B-8704-2011 OI Mazin, Ben/0000-0003-0526-1114 NR 13 TC 67 Z9 67 U1 1 U2 14 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD MAY 26 PY 2008 VL 92 IS 21 AR 212504 DI 10.1063/1.2937855 PG 3 WC Physics, Applied SC Physics GA 307FI UT WOS:000256303500046 ER PT J AU Corti, T Luo, BP de Reus, M Brunner, D Cairo, F Mahoney, MJ Martucci, G Matthey, R Mitev, V dos Santos, FH Schiller, C Shur, G Sitnikov, NM Spelten, N Vossing, HJ Borrmann, S Peter, T AF Corti, T. Luo, B. P. de Reus, M. Brunner, D. Cairo, F. Mahoney, M. J. Martucci, G. Matthey, R. Mitev, V. dos Santos, F. H. Schiller, C. Shur, G. Sitnikov, N. M. Spelten, N. Voessing, H. J. Borrmann, S. Peter, T. TI Unprecedented evidence for deep convection hydrating the tropical stratosphere SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID WATER-VAPOR; TRANSPORT; MODEL; TROPOPAUSE; INSTRUMENT; IMPACT; OZONE AB We report on in situ and remote sensing measurements of ice particles in the tropical stratosphere found during the Geophysica campaigns TROCCINOX and SCOUT-O3. We show that the deep convective systems penetrated the stratosphere and deposited ice particles at altitudes reaching 420 K potential temperature. These convective events had a hydrating effect on the lower tropical stratosphere due to evaporation of the ice particles. In contrast, there were no signs of convectively induced dehydration in the stratosphere. C1 [Corti, T.; Luo, B. P.; Peter, T.] ETH, Inst Atmospher & Climate Sci, CH-8092 Zurich, Switzerland. [dos Santos, F. H.; Schiller, C.; Spelten, N.] Forschungszentrum Julich, Inst Stratospher Res, D-52425 Julich, Germany. [Mahoney, M. J.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Martucci, G.] PST VEGA Venezia, Consorzio Venezia Ric, I-30175 Venice, Italy. [Matthey, R.; Mitev, V.] Ctr Suisse Elect & Microtech SA, CH-2000 Neuchatel, Switzerland. [Shur, G.; Sitnikov, N. M.] Cent Aerol Observ, Dolgoprudnyi Moscow 141700, Russia. [de Reus, M.; Voessing, H. J.; Borrmann, S.] Johannes Gutenberg Univ Mainz, Inst Atmospher Phys, D-55099 Mainz, Germany. [Brunner, D.] EMPA, Lab Air Pollut & Environm Technol, CH-8600 Dubendorf, Switzerland. [Cairo, F.] CNR, Ist Sci Atmosfera & Clima, I-00133 Rome, Italy. RP Corti, T (reprint author), ETH, Inst Atmospher & Climate Sci, CH-8092 Zurich, Switzerland. EM tcorti@env.ethz.ch RI Corti, Thierry/C-6332-2008; Brunner, Dominik/A-1255-2009; Borrmann, Stephan/E-3868-2010; Schiller, Cornelius/B-1004-2013; cairo, francesco/C-7460-2015 OI Brunner, Dominik/0000-0002-4007-6902; cairo, francesco/0000-0002-2886-2601 NR 23 TC 89 Z9 89 U1 2 U2 16 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 EI 1944-8007 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAY 24 PY 2008 VL 35 IS 10 AR L10810 DI 10.1029/2008GL033641 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 304VT UT WOS:000256137900004 ER PT J AU Pickett, HM Drouin, BJ Canty, T Salawitch, RJ Fuller, RA Perun, VS Livesey, NJ Waters, JW Stachnik, RA Sander, SP Traub, WA Jucks, KW Minschwaner, K AF Pickett, H. M. Drouin, B. J. Canty, T. Salawitch, R. J. Fuller, R. A. Perun, V. S. Livesey, N. J. Waters, J. W. Stachnik, R. A. Sander, S. P. Traub, W. A. Jucks, K. W. Minschwaner, K. TI Validation of Aura Microwave Limb Sounder OH and HO2 measurements SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID EOS MLS; SATELLITE; RADICALS; OZONE; H2O; O-3 AB The Microwave Limb Sounder (MLS) instrument on the Aura satellite obtains global measurements of both OH and HO2 radicals. This paper describes the precision and systematic errors of the MLS version v2.2 of the retrieval software. Estimated systematic errors are less than 8% for OH over 32-0.003 hPa and HO2 over 6.8-0.21 hPa. Comparison of measurements from MLS OH and HO2 profiles and three balloon-based instruments show good agreement among themselves and with a photochemical model using standard chemistry (i.e., recommended rate constants). Similarly, good agreement is seen between column OH found by integrating satellite profiles and ground-based measurements of column OH. The agreement between measured and modeled OH and HO2 is improved following perturbations to the rate constants O+OH and OH+HO2 that are within the recommended uncertainties. Measurements of OH obtained a decade ago by the Middle Atmosphere High-Resolution Spectrograph Investigation (MAHRSI) are smaller than MLS measurements by 20% at 70 km, are similar to MLS data near 50 km, and are 50% larger than MLS observations near 42 km. The MLS and MAHRSI measurements of OH overlap at the limit of their respective 2-sigma uncertainties. Most importantly, we find the shape of the OH profile measured by MLS is simulated well using standard chemistry. C1 [Pickett, H. M.; Drouin, B. J.; Canty, T.; Salawitch, R. J.; Fuller, R. A.; Perun, V. S.; Livesey, N. J.; Waters, J. W.; Stachnik, R. A.; Sander, S. P.; Traub, W. A.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Jucks, K. W.] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. [Minschwaner, K.] New Mexico Inst Min & Technol, Socorro, NM 87801 USA. RP Pickett, HM (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM herbert.m.pickett@jpl.nasa.gov RI Salawitch, Ross/B-4605-2009; Canty, Timothy/F-2631-2010 OI Salawitch, Ross/0000-0001-8597-5832; Canty, Timothy/0000-0003-0618-056X NR 25 TC 26 Z9 26 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 24 PY 2008 VL 113 IS D16 AR D16S30 DI 10.1029/2007JD008775 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 304WG UT WOS:000256139200001 ER PT J AU Kroon, M Veefkind, JP Sneep, M McPeters, RD Bhartia, PK Levelt, PF AF Kroon, M. Veefkind, J. P. Sneep, M. McPeters, R. D. Bhartia, P. K. Levelt, P. F. TI Comparing OMI-TOMS and OMI-DOAS total ozone column data SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID MONITORING INSTRUMENT AB The Ozone Monitoring Instrument (OMI) project team uses two total ozone retrieval algorithms in order to maintain the long-term record established with Total Ozone Mapping Spectrometer (TOMS) data as well as to improve the ozone column estimate using the hyperspectral capability of OMI. The purpose of this study is to assess where the algorithms produce comparable results and where the differences are significant. Starting with the same set of Earth reflectance data, the total ozone data used in this study have been derived using OMI-TOMS and OMI-Differential Optical Absorption Spectroscopy (DOAS) algorithms. OMI-TOMS is based on the TOMS version 8 algorithm that has been used to process TOMS data taken since November 1978. The OMI-DOAS retrieval algorithm was developed specifically for OMI. It takes advantage of the hyperspectral feature of the OMI instrument to reduce errors due to aerosols, clouds, surface, and sulfur dioxide from volcanic eruptions. The OMI-DOAS algorithm also has improved correction for cloud height. The mean differences in the ozone column derived from the two algorithms vary from 0 to 9 DU (0-3%), and their correlation coefficients vary between 0.89 and 0.99 with latitude and season. The largest differences occur in the polar regions and over clouds. Some of the differences are due to stray light, dark current, and other instrumental errors that have been corrected in the new version of the OMI radiance/irradiance data set (collection 3). Other differences are algorithmic. OMI-DOAS algorithmic errors identified through this analysis are also being corrected in collection 3 reprocessing. However, for consistency with the long-term TOMS record, OMI-TOMS collection 3 data will still be based on the TOMS V8 algorithm. Preliminary analysis shows much better agreement in the two total ozone data sets after reprocessing. Reprocessed collection 3 data from both algorithms will be available before the end of 2007. Continuing the TOMS total ozone column data record that dates back to November 1978 is the primary OMI mission goal that is achievable with either OMI total ozone column data product. C1 [Kroon, M.; Veefkind, J. P.; Sneep, M.; Levelt, P. F.] Royal Netherlands Meteorol Inst, NL-3730 AE De Bilt, Netherlands. [McPeters, R. D.; Bhartia, P. K.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Kroon, M (reprint author), Royal Netherlands Meteorol Inst, POB 201, NL-3730 AE De Bilt, Netherlands. EM mark.kroon@knmi.nl RI McPeters, Richard/G-4955-2013; Bhartia, Pawan/A-4209-2016 OI McPeters, Richard/0000-0002-8926-8462; Bhartia, Pawan/0000-0001-8307-9137 NR 13 TC 37 Z9 39 U1 0 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 23 PY 2008 VL 113 IS D16 AR D16S28 DI 10.1029/2007JD008798 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 304WF UT WOS:000256139100001 ER PT J AU Reeves, JM Wilson, JC Brock, CA Bui, TP AF Reeves, J. M. Wilson, J. C. Brock, C. A. Bui, T. P. TI Comparison of aerosol extinction coefficients, surface area density, and volume density from SAGE II and in situ aircraft measurements SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID STRATOSPHERIC AEROSOL; SULFURIC-ACID; NORTHERN MIDLATITUDES; NASA ER-2; POAM II; VALIDATION; TROPOSPHERE; HYGROMETER; ALGORITHM; INVERSION AB Aerosol size distributions measured in the lower stratosphere by the University of Denver's focused cavity aerosol size spectrometer (FCAS) were used to calculate aerosol extinction coefficients, surface area densities, and volume densities for comparison with the Stratospheric Aerosol and Gas Experiment (SAGE) II version 6.20 data products. Profiles from ten high-altitude aircraft flights, ranging approximately 8.5 to 20.5 km altitude, are compared with nearby SAGE II occultation events. Nine of the flights date from late 1995 through 1997, and one is from early 2004. Extinctions are found to agree within instrumental uncertainties except at 386 nm below 17 km, where the SAGE II values are systematically low despite their large errors. Above 12 km, where the comparisons are statistically significant, the SAGE II volume density is about 35% lower than the FCAS measurements, though just within combined uncertainties, while the SAGE II surface area density is low compared to FCAS by a factor of 1.5 to 3. The limitations of principal component analysis may account for up to two thirds of the discrepancy in surface area density. C1 [Reeves, J. M.; Wilson, J. C.] Univ Denver, Dept Engn, Denver, CO 80208 USA. NOAA, Boulder, CO USA. [Bui, T. P.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Reeves, JM (reprint author), Univ Denver, Dept Engn, 2390 S York St,Room 200, Denver, CO 80208 USA. EM jreeves@du.edu RI Brock, Charles/G-3406-2011; Manager, CSD Publications/B-2789-2015 OI Brock, Charles/0000-0002-4033-4668; NR 29 TC 5 Z9 7 U1 1 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 23 PY 2008 VL 113 IS D10 AR D10202 DI 10.1029/2007JD009357 PG 8 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 304VZ UT WOS:000256138500001 ER PT J AU Richards, NAD Osterman, GB Browell, EV Hair, JW Avery, M Li, QB AF Richards, Nigel A. D. Osterman, Gregory B. Browell, Edward V. Hair, Johnathan W. Avery, Melody Li, Qinbin TI Validation of Tropospheric Emission Spectrometer ozone profiles with aircraft observations during the intercontinental chemical transport experiment-B SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID AIR-MASS CHARACTERISTICS; AEROSOL DISTRIBUTIONS; TES AB The Tropospheric Emission Spectrometer (TES) is an infrared instrument that was launched on board NASA's Aura satellite in 2004. TES is the first instrument to provide vertical information on tropospheric ozone while simultaneously measuring CO on a global basis. Before they may be used for scientific study, TES profiles must first be validated to determine if there are any systematic biases present. In this study we present a validation of TES tropospheric ozone using airborne differential absorption lidar (DIAL) profiles obtained during the Intercontinental Chemical Transport Experiment-B (INTEX-B) campaign, which took place during March-May 2006. During INTEX-B the NASA DC-8 aircraft conducted several flights, which allowed the DIAL instrument to obtain ozone profile measurements that were spatially coincident with TES special observations in three different geographical regions. Here we present comparisons of TES and DIAL tropospheric ozone profiles that show that, on average, TES exhibits a small positive bias in the troposphere of 5-15%. We also examine the use of in situ profile observations for the validation of TES tropospheric ozone, and we find these to be of most use in clean regions where the background ozone field is homogeneous. C1 [Richards, Nigel A. D.; Osterman, Gregory B.; Li, Qinbin] CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA. [Browell, Edward V.; Hair, Johnathan W.; Avery, Melody] NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Richards, NAD (reprint author), Univ Leeds, Sch Earth & Environm, Inst Atmospher Sci, Leeds LS2 9JT, W Yorkshire, England. EM n.richards@see.leeds.ac.uk NR 21 TC 45 Z9 45 U1 0 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 23 PY 2008 VL 113 IS D16 AR D16S29 DI 10.1029/2007JD008815 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 304WF UT WOS:000256139100002 ER PT J AU Smith, WO Comiso, JC AF Smith, Walker O., Jr. Comiso, Josefino C. TI Influence of sea ice on primary production in the Southern Ocean: A satellite perspective SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID PHYTOPLANKTON ASSEMBLAGE COMPOSITION; LIGHT-SATURATED PHOTOSYNTHESIS; ROSS SEA; SURFACE CHLOROPHYLL; BELLINGSHAUSEN SEA; SPATIAL PATTERNS; PACIFIC SECTOR; ANNULAR MODE; SCOTIA SEA; EDGE ZONE AB Sea ice in the Southern Ocean is a major controlling factor on phytoplankton productivity, but the relationship is modified by regional differences in atmospheric and oceanographic conditions. We used the phytoplankton biomass, photosynthetically active radiation (PAR), and cloud cover data from Sea-viewing Wide Field of View Sensor (SeaWiFS), ice concentrations data from Special Sensor Microwave Imager (SSM/I) and Advanced Microwave Scanning Radiometer-EOS (AMSR-E), sea-surface temperature data from advanced very high resolution radiometer (AVHRR), and a vertically integrated model to estimate primary productivity south of 60 degrees S. We also selected six areas within the Southern Ocean and analyzed the variability of the primary productivity and trends through time. We found substantial interannual variability in productivity from 1997 to 2005 in all regions of the Southern Ocean, and this variability appeared to be driven in large part by ice dynamics. The most productive regions of Antarctic waters were the continental shelves, and no sustained blooms occurred in waters of greater depth (> 1000 m). We suggest that this is due to the slightly greater mixed layer depths found in waters off the continental shelf, and that the interactive effects of iron and irradiance result in the limitation of phytoplankton biomass over large regions of the Southern Ocean. Annual productivity of the Southern Ocean averaged 23.65 g C m(-2) a(-1), but yearly means for the years between 1998 and 2004 ranged from 22.10 to 25.49 g C m(-2) d(-1), respectively. Annual primary productivity over the entire Southern Ocean appears to have increased significantly since 1998, and much of this increase was confined to the months of January and February. Causes for this trend are presently unclear. C1 [Smith, Walker O., Jr.] Virginia Inst Marine Sci, Coll William & Mary, Gloucester Point, VA 23062 USA. [Comiso, Josefino C.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Smith, WO (reprint author), Virginia Inst Marine Sci, Coll William & Mary, Gloucester Point, VA 23062 USA. EM wos@vims.edu NR 63 TC 63 Z9 63 U1 1 U2 16 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD MAY 23 PY 2008 VL 113 IS C5 AR C05S93 DI 10.1029/2007JC004251 PG 19 WC Oceanography SC Oceanography GA 304WR UT WOS:000256140300003 ER PT J AU Worby, AP Markus, T Steer, AD Lytle, VI Massom, RA AF Worby, Anthony P. Markus, Thorsten Steer, Adam D. Lytle, Victoria I. Massom, Robert A. TI Evaluation of AMSR-E snow depth product over East Antarctic sea ice using in situ measurements and aerial photography SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID MICROWAVE SIGNATURES; WEDDELL SEA; SEGMENTATION; VARIABILITY; WINTER; COVER AB The Antarctic Remote Ice Sensing Experiment (ARISE) was conducted in the East Antarctic sea ice zone during September-October 2003. A key objective of this program was the acquisition of in situ measurements suitable for evaluating the EOS Aqua Advanced Microwave Scanning Radiometer (AMSR-E) snow depth product. A strategy is presented for comparing snow thickness measurements over spatial scales ranging from point measurements to satellite pixels. In situ measurements of snow thickness were taken across eight Lagrangian grid cells defined and tracked using an array of drifting buoys. These data are coupled with ice-type analyses from digital aerial photographs to calculate area-averaged snow thicknesses that are compared with the AMSR-E derived snow thickness product. The results show considerable underestimates of the AMSR-E snow depths for rough sea ice by a factor of 2.3. We investigate the impact of underlying sea ice roughness on snow depth retrievals and conclude that in situ measurements of snow thickness underrepresent snow depth over rough ice, which is then not adequately accounted for in the development of the algorithm coefficients. C1 [Worby, Anthony P.; Steer, Adam D.; Massom, Robert A.] Univ Tasmania, Australian Antarctic Div, Hobart, Tas 7001, Australia. [Worby, Anthony P.; Steer, Adam D.; Massom, Robert A.] Univ Tasmania, Cooperat Res Ctr Antartic Climate & Ecosyst, Hobart, Tas 7001, Australia. [Markus, Thorsten] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Lytle, Victoria I.] Norwegian Polar Res Inst, CliC Int Project Off, N-9296 Tromso, Norway. RP Worby, AP (reprint author), Univ Tasmania, Australian Antarctic Div, Private Bag 80, Hobart, Tas 7001, Australia. EM a.worby@utas.edu.au RI Worby, Anthony/A-2373-2012; Markus, Thorsten/D-5365-2012; OI Steer, Adam/0000-0003-0046-7236 NR 27 TC 35 Z9 35 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9275 EI 2169-9291 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD MAY 23 PY 2008 VL 113 IS C5 AR C05S94 DI 10.1029/2007JC004181 PG 13 WC Oceanography SC Oceanography GA 304WR UT WOS:000256140300001 ER PT J AU McAdoo, DC Farrell, SL Laxon, SW Zwally, HJ Yi, DH Ridout, AL AF McAdoo, David C. Farrell, Sinead Louise Laxon, Seymour W. Zwally, H. Jay Yi, Donghui Ridout, Andy L. TI Arctic Ocean gravity field derived from ICESat and ERS-2 altimetry: Tectonic implications SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article ID SATELLITE ALTIMETRY; CONTINENTAL-MARGIN; ANOMALIES; RIDGE; GEOSAT; BASIN AB A new, detailed marine gravity field for the persistently ice-covered Arctic Ocean, derived entirely from satellite data, reveals important new tectonic features in both the Amerasian and Eurasian basins. Reprocessed Geoscience Laser Altimeter System (GLAS) data collected by NASA's Ice Cloud and land Elevation Satellite (ICESat) between 2003 and 2005 have been combined with 8 years worth of retracked radar altimeter data from ESA's ERS-2 satellite to produce the highest available resolution gravity mapping of the entire Arctic Ocean complete to 86 degrees N. This ARCtic Satellite-only (ARCS) marine gravity field uniformly and confidently resolves marine gravity to wavelengths as short as 35 km. ARCS relies on a Gravity Recovery and Climate Experiment (GRACE)-only satellite gravity model at long (> 580 km) wavelengths and plainly shows tectonic fabric and numerous details imprinted in the Arctic seafloor, in particular, in the enigmatic Amerasian Basin (AB). For example, in the Makarov Basin portion of the AB, two north-south trending lineations are likely clues to the highly uncertain seafloor spreading history which formed the AB. C1 [McAdoo, David C.] NOAA, Lab Satellite Altimetry, Silver Spring, MD 20910 USA. [Farrell, Sinead Louise; Laxon, Seymour W.; Ridout, Andy L.] UCL, Ctr Polar Observat & Modelling, London WC1E 6BT, England. [Yi, Donghui] NASA, Goddard Space Flight Ctr, SGT Inc, Greenbelt, MD 20771 USA. [Zwally, H. Jay] NASA, Goddard Space Flight Ctr, Cryospher Sci Branch, Greenbelt, MD 20771 USA. RP McAdoo, DC (reprint author), NOAA, Lab Satellite Altimetry, 1335 EW Highway, Silver Spring, MD 20910 USA. EM dave.mcadoo@noaa.gov; slf@cpom.ucl.ac.uk; swl@cpom.ucl.ac.uk; zwally@icesat2.gsfc.nasa.gov; doughui@icesat2.gsfc.nasa.gov; alr@cpom.ucl.ac.uk RI Laxon, Seymour/C-1644-2008; Farrell, Sinead/F-5586-2010; McAdoo, Dave/F-5612-2010 OI Farrell, Sinead/0000-0003-3222-2751; McAdoo, Dave/0000-0002-7533-5564 NR 42 TC 16 Z9 18 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9313 EI 2169-9356 J9 J GEOPHYS RES-SOL EA JI J. Geophys. Res.-Solid Earth PD MAY 23 PY 2008 VL 113 IS B5 AR B05408 DI 10.1029/2007JB005217 PG 12 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 304XD UT WOS:000256141500002 ER PT J AU Woodcock, CE Allen, R Anderson, M Belward, A Bindschadler, R Cohen, W Gao, F Goward, SN Helder, D Helmer, E Nemani, R Oreopoulos, L Schott, J Thenkabail, PS Vermote, EF Vogelmann, J Wulder, MA Wynne, R AF Woodcock, Curtis E. Allen, Richard Anderson, Martha Belward, Alan Bindschadler, Robert Cohen, Warren Gao, Feng Goward, Samuel N. Helder, Dennis Helmer, Eileen Nemani, Rama Oreopoulos, Lazaros Schott, John Thenkabail, Prasad S. Vermote, Eric F. Vogelmann, James Wulder, Michael A. Wynne, Randolph CA Landsat Sci Team TI Free access to Landsat imagery SO SCIENCE LA English DT Letter C1 [Woodcock, Curtis E.] Boston Univ, Dept Geog & Environm, Boston, MA 02215 USA. [Allen, Richard] Univ Idaho, Res & Extens Ctr, Kimberly, ID 83341 USA. [Anderson, Martha] USDA ARS, Hydrol & Remote Sensing Lab, Beltsville, MD 20705 USA. [Belward, Alan] Commiss European Communities, Joint Res Ctr, Inst Environm & Sustainabil, Global Environm Monitoring Unit, I-21020 Ispra, Italy. [Bindschadler, Robert; Gao, Feng; Oreopoulos, Lazaros] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Cohen, Warren] USDA, Forest Serv, Corvallis, OR 97331 USA. [Goward, Samuel N.] Univ Maryland, Dept Geog, College Pk, MD 20742 USA. [Helder, Dennis] S Dakota State Univ, Dept Elect Engn & Comp Sci, Brookings, SD 57007 USA. [Helmer, Eileen] US Forest Serv, Rocky Mt Forest & Range Expt Stn, Int Inst Trop Forestry, Ft Collins, CO 80526 USA. [Nemani, Rama] NASA, Ames Res Ctr, Ecosyst Sci & Technol Branch, Moffett Field, CA 94035 USA. [Schott, John] Rochester Inst Technol, Chester F Carlson Ctr Imaging Sci, Rochester, NY 14623 USA. [Vermote, Eric F.] IWMI, Colombo, Sri Lanka. [Vogelmann, James] USGS EROS, SAIC, Sioux Falls, SD 57198 USA. [Wulder, Michael A.] Canadian Forest Serv, Pacific Forestry Ctr, Victoria, BC V8Z 1M5, Canada. [Wynne, Randolph] Virginia Tech, Dept Forestry, Blacksburg, VA 24061 USA. RP Woodcock, CE (reprint author), Boston Univ, Dept Geog & Environm, Boston, MA 02215 USA. EM curtis@bu.edu RI Oreopoulos, Lazaros/E-5868-2012; Vermote, Eric/K-3733-2012; Wulder, Michael/J-5597-2016; OI Oreopoulos, Lazaros/0000-0001-6061-6905; Wulder, Michael/0000-0002-6942-1896; Vogelmann, James/0000-0002-0804-5823; Anderson, Martha/0000-0003-0748-5525 NR 0 TC 199 Z9 206 U1 6 U2 43 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD MAY 23 PY 2008 VL 320 IS 5879 BP 1011 EP 1011 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 303RY UT WOS:000256059800013 PM 18497274 ER PT J AU Squyres, SW Arvidson, RE Ruff, S Gellert, R Morris, RV Ming, DW Crumpler, L Farmer, JD Des Marais, DJ Yen, A McLennan, SM Calvin, W Bell, JF Clark, BC Wang, A Mccoy, TJ Schmidt, ME de Souza, PA AF Squyres, S. W. Arvidson, R. E. Ruff, S. Gellert, R. Morris, R. V. Ming, D. W. Crumpler, L. Farmer, J. D. Des Marais, D. J. Yen, A. McLennan, S. M. Calvin, W. Bell, J. F., III Clark, B. C. Wang, A. McCoy, T. J. Schmidt, M. E. de Souza, P. A., Jr. TI Detection of silica-rich deposits on Mars SO SCIENCE LA English DT Article ID GEOTHERMAL FIELDS; GUSEV CRATER; HOT-SPRINGS; NEW-ZEALAND; PRECIPITATION; SPECTROSCOPY; MINERALOGY; POWDERS; TES AB Mineral deposits on the martian surface can elucidate ancient environmental conditions on the planet. Opaline silica deposits ( as much as 91 weight percent SiO2) have been found in association with volcanic materials by the Mars rover Spirit. The deposits are present both as light- toned soils and as bedrock. We interpret these materials to have formed under hydrothermal conditions and therefore to be strong indicators of a former aqueous environment. This discovery is important for understanding the past habitability of Mars because hydrothermal environments on Earth support thriving microbial ecosystems. C1 [Squyres, S. W.; Bell, J. F., III] Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. [Arvidson, R. E.; Wang, A.] Washington Univ, Dept Earth & Planetary Sci, St Louis, MO 63130 USA. [Ruff, S.; Farmer, J. D.] Arizona State Univ, Sch Earth & Space Explorat, Tempe, AZ 85287 USA. [Gellert, R.] Univ Guelph, Dept Phys, Guelph, ON N1G 2W1, Canada. [Morris, R. V.; Ming, D. W.] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. [Crumpler, L.] New Mexico Museum Nat Hist & Sci, Albuquerque, NM 87104 USA. [Des Marais, D. J.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. [Yen, A.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [McLennan, S. M.] SUNY Stony Brook, Dept Geosci, Stony Brook, NY 11794 USA. [Calvin, W.] Univ Nevada, Dept Geol Sci, Reno, NV 89557 USA. [Clark, B. C.] Lockheed Martin Corp, Littleton, CO 80127 USA. [McCoy, T. J.; Schmidt, M. E.] Smithsonian Inst, Natl Museum Nat Hist, Dept Mineral Sci, Washington, DC 20560 USA. [de Souza, P. A., Jr.] CSIRO, Tasmanian Informat & Commun Technol Ctr, Hobart, Tas 7000, Australia. RP Squyres, SW (reprint author), Cornell Univ, Dept Astron, Space Sci Bldg, Ithaca, NY 14853 USA. EM squyres@astro.cornell.edu RI de Souza, Paulo/B-8961-2008; Centre, TasICT/D-1212-2011 OI de Souza, Paulo/0000-0002-0091-8925; NR 34 TC 169 Z9 171 U1 5 U2 37 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 EI 1095-9203 J9 SCIENCE JI Science PD MAY 23 PY 2008 VL 320 IS 5879 BP 1063 EP 1067 DI 10.1126/science.1155429 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 303RY UT WOS:000256059800042 PM 18497295 ER PT J AU Mohammed, PN Knuble, JJ Piepmeier, JR AF Mohammed, P. N. Knuble, J. J. Piepmeier, J. R. TI Analogue kurtosis detector for radio-frequency interference in microwave radiometers SO ELECTRONICS LETTERS LA English DT Article ID MITIGATION; LAND AB An analogue system has been developed for radio frequency interference (RFI) detection in microwave radiometers. The detector measures the higher order moments of the signal and the kurtosis measurement is used to determine the presence of RFI. The hardware comprises a square-law detector and a high-speed analogue multiplier. Because the circuit uses only analogue components at radio and/or intermediate frequencies, it can easily augment conventional radiometer architectures used in both airborne and spaceborne instruments. C1 [Mohammed, P. N.; Knuble, J. J.; Piepmeier, J. R.] NASA, Goddard Space Flight Ctr, Microwave Instruments & Technol Branch, Greenbelt, MD 20771 USA. [Mohammed, P. N.] Univ Maryland, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21250 USA. RP Mohammed, PN (reprint author), NASA, Goddard Space Flight Ctr, Microwave Instruments & Technol Branch, Greenbelt, MD 20771 USA. EM priscilla.n.mohammed@nasa.gov NR 6 TC 0 Z9 0 U1 0 U2 0 PU INST ENGINEERING TECHNOLOGY-IET PI HERTFORD PA MICHAEL FARADAY HOUSE SIX HILLS WAY STEVENAGE, HERTFORD SG1 2AY, ENGLAND SN 0013-5194 J9 ELECTRON LETT JI Electron. Lett. PD MAY 22 PY 2008 VL 44 IS 11 BP 683 EP U35 DI 10.1049/el:20080113 PG 2 WC Engineering, Electrical & Electronic SC Engineering GA 309CE UT WOS:000256437500019 ER PT J AU Soderberg, AM Berger, E Page, KL Schady, P Parrent, J Pooley, D Wang, XY Ofek, EO Cucchiara, A Rau, A Waxman, E Simon, JD Bock, DCJ Milne, PA Page, MJ Barentine, JC Barthelmy, SD Beardmore, AP Bietenholz, MF Brown, P Burrows, A Burrows, DN Byrngelson, G Cenko, SB Chandra, P Cummings, JR Fox, DB Gal-Yam, A Gehrels, N Immler, S Kasliwal, M Kong, AKH Krimm, HA Kulkarni, SR Maccarone, TJ Meszaros, P Nakar, E O'Brien, PT Overzier, RA de Pasquale, M Racusin, J Rea, N York, DG AF Soderberg, A. M. Berger, E. Page, K. L. Schady, P. Parrent, J. Pooley, D. Wang, X. -Y. Ofek, E. O. Cucchiara, A. Rau, A. Waxman, E. Simon, J. D. Bock, D. C. -J. Milne, P. A. Page, M. J. Barentine, J. C. Barthelmy, S. D. Beardmore, A. P. Bietenholz, M. F. Brown, P. Burrows, A. Burrows, D. N. Byrngelson, G. Cenko, S. B. Chandra, P. Cummings, J. R. Fox, D. B. Gal-Yam, A. Gehrels, N. Immler, S. Kasliwal, M. Kong, A. K. H. Krimm, H. A. Kulkarni, S. R. Maccarone, T. J. Meszaros, P. Nakar, E. O'Brien, P. T. Overzier, R. A. de Pasquale, M. Racusin, J. Rea, N. York, D. G. TI An extremely luminous X-ray outburst at the birth of a supernova SO NATURE LA English DT Article ID SHOCK BREAKOUT; RADIO; BURST; AFTERGLOWS; GRB-980425; GRB-060218; EVOLUTION; EMISSION; NOVAE; STARS AB Massive stars end their short lives in spectacular explosions-supernovae-that synthesize new elements and drive galaxy evolution. Historically, supernovae were discovered mainly through their 'delayed' optical light (some days after the burst of neutrinos that marks the actual event), preventing observations in the first moments following the explosion. As a result, the progenitors of some supernovae and the events leading up to their violent demise remain intensely debated. Here we report the serendipitous discovery of a supernova at the time of the explosion, marked by an extremely luminous X-ray outburst. We attribute the outburst to the 'break-out' of the supernova shock wave from the progenitor star, and show that the inferred rate of such events agrees with that of all core-collapse supernovae. We predict that future wide-field X-ray surveys will catch each year hundreds of supernovae in the act of exploding. C1 [Soderberg, A. M.; Berger, E.; Burrows, A.] Princeton Univ, Dept Astrophys Sci, Princeton, NJ 08544 USA. [Soderberg, A. M.; Berger, E.] Carnegie Inst Washington Observ, Pasadena, CA 91101 USA. [Page, K. L.; Beardmore, A. P.; O'Brien, P. T.] Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. [Schady, P.; Page, M. J.; de Pasquale, M.] UCL, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England. [Parrent, J.] Dartmouth Coll, Dept Phys & Astron, Hanover, NH 03755 USA. [Pooley, D.] Univ Wisconsin, Dept Astron, Madison, WI 53706 USA. [Wang, X. -Y.] Nanjing Univ, Dept Astron, Nanjing 210093, Peoples R China. [Ofek, E. O.; Rau, A.; Simon, J. D.; Kasliwal, M.; Kulkarni, S. R.] CALTECH, Dept Astron, Pasadena, CA 91125 USA. [Cucchiara, A.; Brown, P.; Burrows, D. N.; Fox, D. B.; Meszaros, P.; Racusin, J.] Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. [Waxman, E.; Gal-Yam, A.] Weizmann Inst Sci, Fac Phys, IL-76100 Rehovot, Israel. [Bock, D. C. -J.] Univ Calif Berkeley, Radio Astron Lab, Berkeley, CA 94720 USA. [Milne, P. A.] Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. [Barentine, J. C.] Univ Texas Austin, Dept Astron, Austin, TX 78712 USA. [Barthelmy, S. D.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Bietenholz, M. F.] York Univ, Dept Phys & Astron, N York, ON M3J 1P3, Canada. [Bietenholz, M. F.] Hartebeestehoek Radio Observ, ZA-1740 Krugersdorp, South Africa. [Byrngelson, G.] Clemson Univ, Dept Phys & Astron, Clemson, SC 29634 USA. [Cenko, S. B.; Nakar, E.] CALTECH, Space Radiat Lab, Pasadena, CA 91125 USA. [Chandra, P.] Univ Virginia, Dept Astron, Charlottesville, VA 22904 USA. [Cummings, J. R.; Gehrels, N.; Immler, S.; Krimm, H. A.] CRESST, Greenbelt, MD 20771 USA. [Cummings, J. R.; Gehrels, N.; Immler, S.; Krimm, H. A.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Kong, A. K. H.] Natl Tsing Hua Univ, Inst Astron, Hsinchu, Taiwan. [Kong, A. K. H.] Natl Tsing Hua Univ, Dept Phys, Hsinchu, Taiwan. [Krimm, H. A.] Univ Space Res Assoc, Columbia, MD 21044 USA. [Maccarone, T. J.] Univ Southampton, Sch Phys & Astron, Southampton SO17 1BJ, Hants, England. [Overzier, R. A.] Max Planck Inst Astrophys, D-85748 Garching, Germany. [Rea, N.] Univ Amsterdam, Astron Inst Anton Pannekoek, NL-1098 SJ Amsterdam, Netherlands. [York, D. G.] Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. RP Soderberg, AM (reprint author), Princeton Univ, Dept Astrophys Sci, Ivy Lane, Princeton, NJ 08544 USA. EM alicia@astro.princeton.edu RI Racusin, Judith/D-2935-2012; Barthelmy, Scott/D-2943-2012; Gehrels, Neil/D-2971-2012; WAXMAN, ELI/K-1557-2012; Rea, Nanda/I-2853-2015 OI Rea, Nanda/0000-0003-2177-6388 NR 44 TC 266 Z9 270 U1 1 U2 24 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 EI 1476-4687 J9 NATURE JI Nature PD MAY 22 PY 2008 VL 453 IS 7194 BP 469 EP 474 DI 10.1038/nature06997 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 303EL UT WOS:000256023700032 PM 18497815 ER PT J AU Pogorzelski, RJ AF Pogorzelski, Ronald J. TI Generalization of the linearized discrete model of coupled oscillator arrays to account for coupling delay SO RADIO SCIENCE LA English DT Article ID LOCKING PHENOMENA AB Arrays of mutually injection locked oscillators have been proposed as a means of providing properly phased excitations for the elements of a phased array antenna. Analysis of such oscillator arrays has typically made use of Van der Pol's oscillator model and Adler's theory of injection locking resulting in a system of nonlinear differential equations for the phases of the oscillators. The solution resulting from a linearization of this formulation is noncausal because it does not account for time delay in the interoscillator coupling. The present analysis extends the linearlized formulation to account for coupling delay and thus yields a causal solution. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Pogorzelski, RJ (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM ronald.j.pogorzelski@jpl.nasa.gov NR 8 TC 3 Z9 3 U1 1 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0048-6604 J9 RADIO SCI JI Radio Sci. PD MAY 22 PY 2008 VL 43 IS 4 AR RS4070 DI 10.1029/2007RS003727 PG 8 WC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications SC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications GA 304XR UT WOS:000256142900001 ER PT J AU Pogorzelski, RJ AF Pogorzelski, Ronald J. TI Continuum modeling of coupled oscillator arrays with coupling delay SO RADIO SCIENCE LA English DT Article AB The previously published linearized continuum model of a linear (one-dimensional) array of mutually injection locked oscillators is generalized to include the effects of time delay in the interoscillator coupling. This generalization is motivated by a desire for causal solutions describing the dynamics of the phase distribution in the aperture of a phase array antenna driven by such an array of oscillators. The solutions for the phase dynamics will, in general, be noncausal unless the coupling delay is taken into account. In the present formulation the coupling delay is represented by an exponential factor introduced in the Laplace transform of the partial differential equation arising in the continuum model. As a result of this, the transform of the phase distribution exhibits an infinite set of branch points in the complex frequency plane and the inverse transform is computed as the sum of the integrals around the branch cuts. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Pogorzelski, RJ (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM ronald.j.pogorzelski@jpl.nasa.gov NR 3 TC 3 Z9 3 U1 2 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0048-6604 J9 RADIO SCI JI Radio Sci. PD MAY 22 PY 2008 VL 43 IS 4 AR RS4S04 DI 10.1029/2007RS003741 PG 12 WC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications SC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications GA 304XR UT WOS:000256142900002 ER PT J AU Goetz, W Leer, K Gunnlaugsson, HP Bartlett, P Basso, B Bell, J Bertelsen, P Binau, CS Chu, PC Gorevan, S Hansen, MF Hviid, SF Kinch, KM Klingelhofer, G Kusack, A Madsen, MB Ming, DW Morris, RV Mumm, E Myrick, T Olsen, M Squyres, SW Wilson, J Yen, A AF Goetz, Walter Leer, Kristoffer Gunnlaugsson, Haraldur P. Bartlett, Paul Basso, Brandon Bell, Jim Bertelsen, Preben Binau, Charlotte S. Chu, Phillip C. Gorevan, S. Hansen, Mikkel F. Hviid, Stubbe F. Kinch, Kjartan M. Klingelhoefer, Goeastar Kusack, Alastair Madsen, Morten B. Ming, Douglas W. Morris, Richard V. Mumm, Erik Myrick, Tom Olsen, Malte Squyres, Steven W. Wilson, Jack Yen, Albert TI Search for magnetic minerals in Martian rocks: Overview of the Rock Abrasion Tool (RAT) magnet investigation on Spirit and Opportunity SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID EXPLORATION ROVER MISSION; MERIDIANI-PLANUM; MOSSBAUER SPECTROMETER; SNC METEORITES; GUSEV CRATER; MARS; CHEMISTRY; HEMATITE; SOILS; HYSTERESIS AB The Rock Abrasion Tool (RAT) on board the Mars Exploration Rovers (MER) is a grinding tool designed to remove dust coatings and/or weathering rinds from rocks and expose fresh rock material. Four magnets of different strengths that are built into the structure of the RAT have been attracting substantial amounts of magnetic material during RAT activities from rocks throughout both rover missions. The RAT magnet experiment as performed on Spirit demonstrates the presence of a strongly ferrimagnetic phase in Gusev crater rocks, which based on Mossbauer and visible/near-infrared reflectance spectra is interpreted as magnetite. The amount of abraded rock material adhering to the magnets varied strongly during the mission and is correlated in a consistent way to the amount of magnetite inferred from Mossbauer spectra for the corresponding rock. The RAT magnet experiment as performed on Opportunity also indicates the presence of a strongly ferrimagnetic phase in outcrops, such as magnetite or an altered version of magnetite. However, the evidence is weaker than in the case of Spirit. According to data from the a particle X-ray spectrometer (APXS) and the Mossbauer spectrometer (MB), the Eagle crater outcrops should not contain magnetite and their magnetization should not exceed 0.03 A m(2) kg(-1). However, this assertion seems to be in contradiction with the results of the RAT magnet experiment. The evidence for a strongly ferrimagnetic phase at low abundance in the Meridiani outcrops is discussed. C1 [Goetz, Walter; Hviid, Stubbe F.] Max Planck Inst Sonnensyst Forsch, D-37191 Katlenburg Lindau, Germany. [Goetz, Walter; Leer, Kristoffer; Bertelsen, Preben; Binau, Charlotte S.] Univ Copenhagen, Niels Bohr Inst, DK-2100 Copenhagen, Denmark. [Gunnlaugsson, Haraldur P.] Aarhus Univ, Inst Phys & Astron, DK-8000 Aarhus, Denmark. [Bartlett, Paul; Basso, Brandon; Chu, Phillip C.; Gorevan, S.; Kusack, Alastair; Mumm, Erik; Myrick, Tom; Wilson, Jack] Honeybee Robot, New York, NY 10001 USA. [Bell, Jim; Kinch, Kjartan M.; Squyres, Steven W.] Cornell Univ, Dept Astron, New York, NY 14853 USA. [Hansen, Mikkel F.] Danish Techn Univ, Dept Micro & Nanotechnol, DK-2800 Lyngby, Denmark. [Klingelhoefer, Goeastar] Johannes Gutenberg Univ Mainz, Inst Inorgan & Analyt Chem, D-55128 Mainz, Germany. [Ming, Douglas W.; Morris, Richard V.] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. [Yen, Albert] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Goetz, W (reprint author), Max Planck Inst Sonnensyst Forsch, D-37191 Katlenburg Lindau, Germany. EM goetz@mps.mpg.de RI Hansen, Mikkel/A-3024-2012; Madsen, Morten/D-2082-2011; Kinch, Kjartan/C-5742-2015 OI Hansen, Mikkel/0000-0003-3333-2856; Madsen, Morten/0000-0001-8909-5111; Kinch, Kjartan/0000-0002-4629-8880 NR 38 TC 5 Z9 5 U1 0 U2 14 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9097 EI 2169-9100 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD MAY 21 PY 2008 VL 113 IS E5 AR E05S90 DI 10.1029/2006JE002819 PG 27 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 304WT UT WOS:000256140500001 ER PT J AU Skinner, GK AF Skinner, Gerald K. TI Sensitivity of coded mask telescopes SO APPLIED OPTICS LA English DT Article ID X-RAY TELESCOPE; UNIFORMLY REDUNDANT ARRAYS; GAMMA-RAY; BINARY ARRAYS; APERTURE ARRAYS; PERFORMANCE; ASTRONOMY; CAMERAS; IMAGES; MONITOR AB Simple formulas are often used to estimate the sensitivity of coded mask x-ray or gamma-ray telescopes, but these are strictly applicable only if a number of basic assumptions are met. Complications arise, for example, if a grid structure is used to support the mask elements, if the detector spatial resolution is not good enough to completely resolve all the detail in the shadow of the mask, or if any of a number of other simplifying conditions are not fulfilled. We derive more general expressions for the Poisson-noise-limited sensitivity of astronomical telescopes using the coded mask technique, noting explicitly in what circumstances they are applicable. The emphasis is on using nomenclature and techniques that result in simple and revealing results. Where no convenient expression is available a procedure is given that allows the calculation of the sensitivity. We consider certain aspects of the optimization of the design of a coded mask telescope and show that when the detector spatial resolution and the mask to detector separation are fixed, the best source location accuracy is obtained when the mask elements are equal in size to the detector pixels. (c) 2008 Optical Society of America. C1 [Skinner, Gerald K.] Univ Maryland, College Pk, MD 20742 USA. [Skinner, Gerald K.] Ctr Res & Explorat Space Sci Technol, Greenbelt, MD 20771 USA. [Skinner, Gerald K.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Skinner, GK (reprint author), Univ Maryland, College Pk, MD 20742 USA. EM skinner@milkyway.gsfc.nasa.gov NR 54 TC 14 Z9 14 U1 0 U2 5 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD MAY 20 PY 2008 VL 47 IS 15 BP 2739 EP 2749 DI 10.1364/AO.47.002739 PG 11 WC Optics SC Optics GA 312SQ UT WOS:000256691500001 PM 18493279 ER PT J AU Galliano, F Madden, SC Tielens, AGGM Peeters, E Jones, AP AF Galliano, Frederic Madden, Suzanne C. Tielens, Alexander G. G. M. Peeters, Els Jones, Anthony P. TI Variations of the mid-IR aromatic features inside and among galaxies SO ASTROPHYSICAL JOURNAL LA English DT Review DE galaxies : dwarf; galaxies : starburst; HII regions; infrared : general; ISM : structure ID SPITZER-SPACE-TELESCOPE; UNIDENTIFIED INFRARED-EMISSION; LOW-METALLICITY ENVIRONMENTS; SPECTRAL ENERGY-DISTRIBUTION; INTERSTELLAR DUST MODELS; SMALL-MAGELLANIC-CLOUD; H-II REGIONS; HYDROCARBON EMISSION; SPIRAL GALAXIES; MU-M AB We present the results of a systematic study of mid-IR spectra of Galactic regions, Magellanic H II regions, and galaxies of various types (dwarf, spiral, starburst), observed by the satellites ISO and Spitzer. We study the relative variations of the 6.2, 7.7, 8.6, and 11.3 mu m features inside spatially resolved objects (such as M82, M51, 30 Doradus, M17, and the Orion Bar), as well as among 90 integrated spectra of 50 objects. Our main results are that the 6.2, 7.7, and 8.6 mu m bands are essentially tied together, while the ratios between these bands and the 11.3 mu m band vary by 1 order of magnitude. This implies that the properties of the PAHs are remarkably universal throughout our sample and that the relative variations of the band ratios are mainly controlled by the fraction of ionized PAHs. In particular, we show that we can rule out both the modification of the PAH size distribution and the mid-IR extinction as an explanation of these variations. Using a few well-studied Galactic regions (including the spectral image of the Orion Bar), we give an empirical relation between the I-6.2/I-11.3 ratio and the ionization/recombination ratio G(0)/n(e)T(gas)(1/2), therefore providing a useful quantitative diagnostic tool of the physical conditions in the regions where the PAH emission originates. Finally, we discuss the physical interpretation of the I-6.2/I-11.3 ratio, on galactic size scales. C1 [Galliano, Frederic] NASA, Goddard Space Flight Ctr, Observ Cosmol Lab, Greenbelt, MD 20910 USA. [Madden, Suzanne C.] CEA Saclay, Serv Astrophys, F-91191 Gif Sur Yvette, France. [Tielens, Alexander G. G. M.; Peeters, Els] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. [Peeters, Els] SETI Inst, Mountain View, CA 94043 USA. [Peeters, Els] Univ Western Ontario, Dept Phys & Astron, London, ON N6A 3K7, Canada. [Jones, Anthony P.] Univ Paris 11, Inst Astrophys Spatiale, F-91405 Orsay, France. RP Galliano, F (reprint author), NASA, Goddard Space Flight Ctr, Observ Cosmol Lab, Greenbelt, MD 20910 USA. EM galliano@astro.umd.edu OI Jones, Anthony/0000-0003-0577-6425 NR 118 TC 139 Z9 139 U1 0 U2 7 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD MAY 20 PY 2008 VL 679 IS 1 BP 310 EP 345 DI 10.1086/587051 PG 36 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 300IX UT WOS:000255818600024 ER PT J AU Sakamoto, T Hullinger, D Sato, G Yamazaki, R Barbier, L Barthelmy, SD Cummings, JR Fenimore, EE Gehrels, N Krimm, HA Lamb, DQ Markwardt, CB Osborne, JP Palmer, DM Parsons, AM Stamatikos, M Tueller, J AF Sakamoto, T. Hullinger, D. Sato, G. Yamazaki, R. Barbier, L. Barthelmy, S. D. Cummings, J. R. Fenimore, E. E. Gehrels, N. Krimm, H. A. Lamb, D. Q. Markwardt, C. B. Osborne, J. P. Palmer, D. M. Parsons, A. M. Stamatikos, M. Tueller, J. TI Global properties of X-ray flashes and X-ray-rich gamma-ray bursts observed by Swift SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; X-rays : bursts ID AFTERGLOW LIGHT CURVES; SPECTRAL CHARACTERISTICS; THEORETICAL IMPLICATIONS; MODEL; FLARES; TELESCOPE; EMISSION; BEPPOSAX; CATALOG; LONG AB We describe and discuss the spectral and temporal characteristics of the prompt emission and X-ray afterglow emission of X-ray flashes (XRFs) and X-ray-rich gamma-ray bursts (XRRs) detected and observed by Swift between 2004 December and 2006 September. We compare these characteristics to a sample of conventional classical gamma-ray bursts (C-GRBs) observed during the same period. We confirm the correlation between E-peak(obs) and fluence noted by others and find further evidence that XRFs, XRRs, and C-GRBs form a continuum. We also confirm that our known redshift sample is consistent with the correlation between the peak energy in the GRB rest frame (E-peak(src)) and the isotropic radiated energy (E-iso), the so-called E-peak(src)-E-iso relation. The spectral properties of X-ray afterglows of XRFs and C-GRBs are similar, but the temporal properties of XRFs and C-GRBs are quite different. We found that the light curves of C-GRB afterglows show a break to steeper indices (shallow-to-steep break) at much earlier times than do XRF afterglows. Moreover, the overall luminosity of XRF X-ray afterglows is systematically smaller by a factor of 2 or more compared to that of C-GRBs. These distinct differences between the X-ray afterglows of XRFs and C-GRBs may be the key to understanding not only the mysterious shallow-to-steep break in X-ray afterglow light curves, but also the unique nature of XRFs. C1 [Sakamoto, T.; Sato, G.; Barbier, L.; Barthelmy, S. D.; Cummings, J. R.; Gehrels, N.; Krimm, H. A.; Markwardt, C. B.; Parsons, A. M.; Stamatikos, M.; Tueller, J.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Sakamoto, T.; Stamatikos, M.] Oak Ridge Associated Univ, Oak Ridge, TN 37831 USA. [Hullinger, D.] Moxtek Inc, Orem, UT 84057 USA. [Sato, G.] JAXA, Inst Space & Astronaut Sci, Kanagawa 2298510, Japan. [Yamazaki, R.] Hiroshima Univ, Dept Phys, Higashihiroshima 7398526, Japan. [Cummings, J. R.] Univ Maryland, Joint Ctr Astrophys, Baltimore, MD 21250 USA. [Fenimore, E. E.; Palmer, D. M.] Los Alamos Natl Lab, Los Alamos, NM 87545 USA. [Krimm, H. A.] Univ Space Res Assoc, Columbia, MD 21044 USA. [Lamb, D. Q.] Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. [Markwardt, C. B.] Univ Maryland, Dept Phys, College Pk, MD 20742 USA. [Osborne, J. P.] Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. RP Sakamoto, T (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RI Barthelmy, Scott/D-2943-2012; Gehrels, Neil/D-2971-2012; Tueller, Jack/D-5334-2012; Parsons, Ann/I-6604-2012 NR 76 TC 49 Z9 49 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD MAY 20 PY 2008 VL 679 IS 1 BP 570 EP 586 DI 10.1086/586884 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 300IX UT WOS:000255818600041 ER PT J AU Hurkett, CP Vaughan, S Osborne, JP O'Brien, PT Page, KL Beardmore, A Godet, O Burrows, DN Capalbi, M Evans, P Gehrels, N Goad, MR Hill, JE Kennea, J Mineo, T Perri, M Starling, R AF Hurkett, C. P. Vaughan, S. Osborne, J. P. O'Brien, P. T. Page, K. L. Beardmore, A. Godet, O. Burrows, D. N. Capalbi, M. Evans, P. Gehrels, N. Goad, M. R. Hill, J. E. Kennea, J. Mineo, T. Perri, M. Starling, R. TI Line searches in Swift X-ray spectra SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; gamma rays : observations; line : identification; methods : data analysis; methods : statistical ID EMISSION-LINES; BURST AFTERGLOWS; ALPHA EMISSION; XMM-NEWTON; SUPERNOVA; MODEL; ABSORPTION; GRB-011211; DISCOVERY; SPECTROSCOPY AB Prior to the launch of the Swift mission several X-ray line detections were reported in gamma-ray burst afterglow spectra. To date, these pre-Swift era results have not been conclusively confirmed. The most contentious issue in this area is the choice of statistical method used to evaluate the significance of these features. In this paper we compare three different methods already extant in the literature for assessing the significance of possible line features and discuss their relative advantages and disadvantages. The methods are demonstrated by application to observations of 40 bursts from the archive of Swift XRT at early times ( cd 10(-1) (periods P < 2.4 hr). This limit is nearly 2 orders of magnitude below recent predictions for early- type WR stars based on strange-mode pulsation simulations, with expected periods in the range 10-30 minutes. Simultaneous spectroscopic observations of WR 111 reveal a normal level of stochastic clumps propagating in the wind, which possibly manifest themselves in the slow 1/f rise in the MOST power spectrum below f similar to 10 cd(-1). Time-frequency analysis of the MOST data shows no obvious short-lived frequencies above the 1 mmag level, in stark contrast to the highly variable cool WR stars WR 123 (WN8) and WR 103 (WC9d), monitored previously by MOST. Radiation pressure therefore appears to be the main, if not sole, driver of WR 111's strong wind. C1 [Moffat, A. F. J.; Muntean, V.] Univ Montreal, Dept Phys, Montreal, PQ H3C 3J7, Canada. [Marchenko, S. V.] Western Kentucky Univ, Dept Phys & Astron, Bowling Green, KY 42101 USA. [Zhilyaev, B. E.] Natl Acad Sci Ukraine, Main Astron Observ, UA-03680 Kiev, Ukraine. [Rowe, J. F.] NASA Ames Res Pk, Moffett Field, CA 94035 USA. [Chene, A. -N.] Herzberg Inst Astrophys, Canadian Gemini Off, Victoria, BC V9E 2E7, Canada. [Matthews, J. M.] Univ British Columbia, Dept Phys & Astron, Vancouver, BC V6T 1Z1, Canada. [Kuschnig, R.; Weiss, W. W.] Univ Vienna, Inst Astron, A-1180 Vienna, Austria. [Guenther, D. B.] St Marys Univ, Dept Phys & Astron, Halifax, NS B3H 3C3, Canada. [Rucinski, S. M.] Univ Toronto, Dept Astron & Astrophys, David Dunlap Observ, Richmond Hill, ON L4C 4Y6, Canada. [Sasselov, D.] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Moffat, AFJ (reprint author), Univ Montreal, Dept Phys, CP 6128,Succ Ctr Ville, Montreal, PQ H3C 3J7, Canada. EM moffat@astro.umontreal.ca; sergey.vm@gmail.com; zhilyaev@mao.kiev.ua; jasonfrowe@gmail.com; muntean@astro.umontreal.ca; andre-nicolas.chene@nrc-cnrc.gc.ca; matthews@astro.ubc.ca; rainer.kuschnig@univie.ac.at; guenther@ap.stmarys.ca; rucinski@astro.utoronto.ca; sasselov@cfa.harvard.edu; gordonwa@uvic.ca; weiss@astro.univie.ac.at NR 26 TC 6 Z9 6 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 2041-8205 J9 ASTROPHYS J LETT JI Astrophys. J. Lett. PD MAY 20 PY 2008 VL 679 IS 1 BP L45 EP L48 DI 10.1086/589237 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 313DR UT WOS:000256721800012 ER PT J AU Vaillancourt, JE Dowell, CD Hildebrand, RH Kirby, L Krejny, MM Li, HB Novak, G Houde, M Shinnaga, H Attard, M AF Vaillancourt, John E. Dowell, C. Darren Hildebrand, Roger H. Kirby, Larry Krejny, Megan M. Li, Hua-Bai Novak, Giles Houde, Martin Shinnaga, Hiroko Attard, Michael TI New results on the submillimeter polarization spectrum of the Orion Molecular Cloud SO ASTROPHYSICAL JOURNAL LETTERS LA English DT Article DE dust, extinction; ISM : clouds; ISM : individual (OMC-1); polarization; submillimeter ID FAR-INFRARED POLARIMETRY; MAGNETIC-FIELDS; GRAIN ALIGNMENT; LINEAR-POLARIZATION; INTERSTELLAR DUST; STAR-FORMATION; CONSTRAINTS; FILAMENT; CAMERA; OMC-1 AB We have used the SHARP polarimeter at the Caltech Submillimeter Observatory to map the polarization at wavelengths of 350 and 450 mu m in a similar to 2 ' x 3 ' region of the Orion Molecular Cloud. The map covers the brightest mm region of the OMC-1 ridge including the Kleinmann-Low (KL) nebula and the submillimeter source Orion-south. The ratio of 450 to 350 mu m polarization is similar to 1.3 +/- 0.3 in the outer parts of the cloud and drops by more than mm a factor of 2 toward KL. The outer cloud ratio is consistent with measurements in other clouds at similar wavelengths and confirms previous measurements placing the minimum of the polarization ratio in dusty molecular clouds at lambda similar to 350 mu m. C1 [Vaillancourt, John E.; Dowell, C. Darren] CALTECH, Div Phys Math & Astron, Pasadena, CA 91125 USA. [Dowell, C. Darren] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Hildebrand, Roger H.; Kirby, Larry] Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. [Hildebrand, Roger H.; Kirby, Larry] Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. [Krejny, Megan M.; Novak, Giles] Northwestern Univ, Dept Phys & Astron, Evanston, IL 60208 USA. [Li, Hua-Bai] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. [Houde, Martin; Attard, Michael] Univ Western Ontario, Dept Phys & Astron, London, ON N6A 3K7, Canada. [Shinnaga, Hiroko] Caltech Submillimeter Observ, Hilo, HI 96720 USA. RP Vaillancourt, JE (reprint author), CALTECH, Div Phys Math & Astron, MS 320-47,1200 E Calif Blvd, Pasadena, CA 91125 USA. EM johnv@submm.caltech.edu; cdd@submm.caltech.edu; roger@oddjob.uchicago.edu; lkirby@oddjob.uchicago.edu; m-krejny@northwestern.edu; hli@cfa.harvard.edu; g-novak@northwestern.edu; houde@astro.uwo.ca; shinnaga@submm.caltech.edu; mattard@uwo.ca NR 39 TC 34 Z9 34 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA J9 ASTROPHYS J LETT JI Astrophys. J. Lett. PD MAY 20 PY 2008 VL 679 IS 1 BP L25 EP L28 DI 10.1086/589152 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 313DR UT WOS:000256721800007 ER PT J AU Ahn, C Torres, O Bhartia, PK AF Ahn, Changwoo Torres, Omar Bhartia, Pawan K. TI Comparison of ozone monitoring instrument UV aerosol products with Aqua/Moderate Resolution Imaging Spectroradiometer and Multiangle Imaging Spectroradiometer observations in 2006 SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article AB [1] An assessment of the consistency of the Ozone Monitoring Instrument (OMI) aerosol products with the results from other satellite aerosol sensors is performed in this paper. The OMI aerosol products include the UltraViolet Aerosol Index (UVAI), Aerosol Absorption Optical Depth (AAOD), and Aerosol Extinction Optical Depth (AOD). The OMI AOD is compared with that from Aqua/Moderate Resolution Imaging Spectroradiometer (MODIS) and Terra/Multiangle Imaging Spectroradiometer (MISR). OMI-retrieved AOD values are generally biased high with respect to MODIS measurements, likely as a result of a calibration offset. Subpixel cloud contamination is the second most important source of error. Other sources of error may contribute to the noise in the retrieval but not necessarily to the systematic bias. In spite of the bias, OMI retrievals show a high degree of correlation with MODIS observations. The analyses of daily cloud-free collocated AOD data between OMI and MODIS show about 0.15 root mean square error on average relative to the linear fit. OMI also shows a reasonable agreement with MODIS and MISR observations in seasonal annual cycles of aerosols over most of the major emission sources of carbonaceous aerosols from biomass burning and mineral dust from deserts. The AAOD is less sensitive to cloud contamination than the AOD. In addition, the information content in the UVAI is well expressed as AAOD with higher correlation than AOD. However, subpixel cloud contamination of OMI footprint (13 x 24 km(2) at nadir) is unavoidable, and retrieved AOD values tend to be overestimated with varying degrees of sensitivity as a function of viewing geometry and aerosol types selected. C1 [Ahn, Changwoo] Sci Syst & Applicat Inc, Lanham, MD 20706 USA. [Torres, Omar; Bhartia, Pawan K.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Torres, Omar] Univ Maryland, Greenbelt, MD USA. RP Ahn, C (reprint author), Sci Syst & Applicat Inc, 10210 Greenbelt Rd,Suite 600, Lanham, MD 20706 USA. EM changwoo_ahn@ssaihq.com RI Torres, Omar/G-4929-2013; Bhartia, Pawan/A-4209-2016 OI Bhartia, Pawan/0000-0001-8307-9137 NR 21 TC 42 Z9 44 U1 1 U2 10 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 20 PY 2008 VL 113 IS D16 AR D16S27 DI 10.1029/2007JD008832 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 304WD UT WOS:000256138900002 ER PT J AU Fried, A Walega, JG Olson, JR Crawford, JH Chen, G Weibring, P Richter, D Roller, C Tittel, FK Heikes, BG Snow, JA Shen, HW O'Sullivan, DW Porter, M Fuelberg, H Halland, J Millet, DB AF Fried, Alan Walega, James G. Olson, Jennifer R. Crawford, Jim H. Chen, Gao Weibring, Petter Richter, Dirk Roller, Chad Tittel, Frank K. Heikes, Brian G. Snow, Julie A. Shen, Haiwei O'Sullivan, Daniel W. Porter, Michael Fuelberg, Henry Halland, Jeremy Millet, Dylan B. TI Formaldehyde over North America and the North Atlantic during the summer 2004 INTEX campaign: Methods, observed distributions, and measurement-model comparisons SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID TUNABLE DIODE-LASER; AMBIENT FORMALDEHYDE; ISOPRENE EMISSIONS; CARBONYL-COMPOUNDS; NASHVILLE; PHOTOCHEMISTRY; HYDROPEROXIDES; PERFORMANCE; ATMOSPHERE; CHEMISTRY AB A tunable diode laser absorption spectrometer (TDLAS) was operated on the NASA DC-8 aircraft during the summer INTEX-NA study to acquire ambient formaldehyde (CH2O) measurements over North America and the North Atlantic Ocean from similar to 0.2 km to similar to 12.5 km altitude spanning 17 science flights. Measurements of CH2O in the boundary layer and upper troposphere over the southeastern United States were anomalously low compared to studies in other years, and this was attributed to the record low temperatures over this region during the summer of 2004. Formaldehyde is primarily formed over the southeast from isoprene, and isoprene emissions are strongly temperature-dependent. Despite this effect, the median upper tropospheric (UT) CH2O mixing ratio of 159 pptv from the TDLAS over continental North America is about a factor of 4 times higher than the median UT value of 40 pptv observed over remote regions during TRACE-P. These observations together with the higher variability observed in this study all point to the fact that continental CH2O levels in the upper troposphere were significantly perturbed during the summer of 2004 relative to more typical background levels in the upper troposphere over more remote regions. The TDLAS measurements discussed in this paper are employed together with box model results in the companion paper by Fried et al. to further examine enhanced CH2O distributions in the upper troposphere due to convection. Measurements of CH2O on the DC-8 were also acquired by a coil enzyme fluorometric system and compared with measurements from the TDLAS system. C1 [Fried, Alan; Walega, James G.; Weibring, Petter; Richter, Dirk; Roller, Chad] Natl Ctr Atmospher Res, Earth Observing Lab, Boulder, CO 80301 USA. [Olson, Jennifer R.; Crawford, Jim H.; Chen, Gao] NASA, Langley Res Ctr, Hampton, VA 23681 USA. [Roller, Chad] Ekips Technol Inc, Norman, OK 73069 USA. [Tittel, Frank K.] Rice Univ, Dept Elect & Comp Engn, Houston, TX 77005 USA. [Heikes, Brian G.; Shen, Haiwei] Univ Rhode Isl, Grad Sch Oceanog, Ctr Atmospher Chem Studies, Narragansett, RI 02882 USA. [Snow, Julie A.] Slippery Rock Univ, Dept Geog Geol & Environm, Slippery Rock, PA 16057 USA. [O'Sullivan, Daniel W.] USN Acad, Dept Chem, Annapolis, MD 21402 USA. [Porter, Michael; Fuelberg, Henry; Halland, Jeremy] Florida State Univ, Dept Meteorol, Tallahassee, FL 32306 USA. [Millet, Dylan B.] Harvard Univ, Dept Earth & Planetary Sci, Cambridge, MA 02138 USA. RP Fried, A (reprint author), Natl Ctr Atmospher Res, Earth Observing Lab, 3450 Mitchell Lane, Boulder, CO 80301 USA. RI Millet, Dylan/G-5832-2012; Crawford, James/L-6632-2013; OI Crawford, James/0000-0002-6982-0934; O'Sullivan, Daniel/0000-0001-9104-5703 NR 33 TC 26 Z9 26 U1 3 U2 19 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 20 PY 2008 VL 113 IS D10 AR D10302 DI 10.1029/2007JD009185 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 304VV UT WOS:000256138100004 ER PT J AU Remer, LA Tanre, D Nakajima, T AF Remer, Lorraine A. Tanre, Didier Nakajima, Teryuki TI Preface to special section on Yoram J. Kaufman symposium on aerosols, clouds, and climate SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Editorial Material ID SKY BRIGHTNESS MEASUREMENTS; SCAR-B EXPERIMENT; SIZE DISTRIBUTION; OPTICAL-PROPERTIES; EOS-MODIS; ATMOSPHERIC CORRECTION; SPECTRAL RADIANCES; POLLUTION AEROSOL; SATELLITE IMAGERY; SMOKE PARTICLES C1 [Remer, Lorraine A.] NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. [Tanre, Didier] Univ Sci & Tech Lille Flandres Artois, Opt Atmospher Lab, Villeneuve Dascq, France. [Nakajima, Teryuki] Univ Tokyo, Ctr Climate Syst Res, Tokyo, Japan. RP Remer, LA (reprint author), NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. NR 75 TC 0 Z9 0 U1 0 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 20 PY 2008 VL 113 IS D14 AR D14S01 DI 10.1029/2008JD009977 PG 4 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 304WC UT WOS:000256138800001 ER PT J AU Das, NN Mohanty, BP Njoku, EG AF Das, N. N. Mohanty, B. P. Njoku, E. G. TI A Markov chain Monte Carlo algorithm for upscaled soil-vegetation-atmosphere-transfer modeling to evaluate satellite-based soil moisture measurements SO WATER RESOURCES RESEARCH LA English DT Article ID SATURATED HYDRAULIC CONDUCTIVITY; SPATIAL VARIABILITY; AMSR-E; MICROWAVE EMISSION; SURFACE-ROUGHNESS; UNSATURATED FLOW; WATER RETENTION; SCALE; PARAMETERS; IMAGES AB A Markov chain Monte Carlo (MCMC) based algorithm was developed to derive upscaled land surface parameters for a soil-vegetation-atmosphere-transfer (SVAT) model using time series data of satellite-measured atmospheric forcings (e. g., precipitation), and land surface states (e. g., soil moisture and vegetation). This study focuses especially on the evaluation of soil moisture measurements of the Aqua satellite based Advanced Microwave Scanning Radiometer (AMSR-E) instrument using the new MCMC-based scaling algorithm. Soil moisture evolution was modeled at a spatial scale comparable to the AMSR-E soil moisture product, with the hypothesis that the characterization of soil microwave emissions and their variations with space and time on soil surface within the AMSR-E footprint can be represented by an ensemble of upscaled soil hydraulic parameters. We demonstrated the features of the MCMC-based parameter upscaling algorithm (from field to satellite footprint scale) within a SVAT model framework to evaluate the satellite-based brightness temperature/soil moisture measurements for different hydroclimatic regions, and identified the temporal effects of vegetation (leaf area index) and other environmental factors on AMSR-E based remotely sensed soil moisture data. The SVAT modeling applied for different hydroclimatic regions revealed the limitation of AMSR-E measurements in high-vegetation regions. The study also suggests that inclusion of soil moisture evolution from the proposed upscaled SVAT model with AMSR-E measurements in data assimilation routine will improve the quality of soil moisture assessment in a footprint scale. The technique also has the potential to derive upscaled parameters of other geophysical properties used in remote sensing of land surface states. The developed MCMC algorithm with SVAT model can be very useful for land-atmosphere interaction studies and further understanding of the physical controls responsible for soil moisture dynamics at different scales. C1 [Das, N. N.; Mohanty, B. P.] Texas A&M Univ, Dept Biol & Agr Engn, College Stn, TX 77843 USA. [Njoku, E. G.] CALTECH, Jet Prop Lab, Water & Carbon Cycles Grp, Pasadena, CA 91109 USA. RP Das, NN (reprint author), Texas A&M Univ, Dept Biol & Agr Engn, 301 C Scoates Hall, College Stn, TX 77843 USA. EM bmohanty@tamu.edu RI Xie, Xingmei/G-7311-2011 NR 65 TC 9 Z9 9 U1 0 U2 12 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD MAY 20 PY 2008 VL 44 IS 5 AR W05416 DI 10.1029/2007WR006472 PG 16 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 304XW UT WOS:000256143400004 ER PT J AU Cabrol, NA Herkenhoff, KE Greeley, R Grin, EA Schroder, C d'Uston, C Weitz, C Yingst, RA Cohen, BA Moore, J Knudson, A Franklin, B Anderson, RC Li, R AF Cabrol, Nathalie A. Herkenhoff, Kenneth E. Greeley, Ronald Grin, Edmond A. Schroeder, Christian d'Uston, Claude Weitz, Catherine Yingst, R. Aileen Cohen, Barbara A. Moore, Jeffrey Knudson, Amy Franklin, Brenda Anderson, Robert C. Li, Ron TI Soil sedimentology at Gusev Crater from Columbia Memorial Station to Winter Haven SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID SPIRIT ROVER; MERIDIANI-PLANUM; LANDING SITE; ROCKS; MARS; SPECTROMETER; SHAPE AB A total of 3140 individual particles were examined in 31 soils along Spirit's traverse. Their size, shape, and texture were quantified and classified. They represent a unique record of 3 years of sedimentologic exploration from landing to sol 1085 covering the Plains Unit to Winter Haven where Spirit spent the Martian winter of 2006. Samples in the Plains Unit and Columbia Hills appear as reflecting contrasting textural domains. One is heterogeneous, with a continuum of angular-to-round particles of fine sand to pebble sizes that are generally dust covered and locally cemented in place. The second shows the effect of a dominant and ongoing dynamic aeolian process that redistributes a uniform population of medium-size sand. The texture of particles observed in the samples at Gusev Crater results from volcanic, aeolian, impact, and water-related processes. C1 [Cabrol, Nathalie A.; Grin, Edmond A.; Moore, Jeffrey] NASA, Ames Res Ctr, Space Sci & Astrobiol Div, Moffett Field, CA 94035 USA. [Cabrol, Nathalie A.; Grin, Edmond A.] SETI Inst Carl Sagan Ctr, Mountain View, CA USA. [Herkenhoff, Kenneth E.] US Geol Survey, Flagstaff, AZ 86001 USA. [Greeley, Ronald; Knudson, Amy] Arizona State Univ, Dept Geol Sci, Tempe, AZ USA. [Schroeder, Christian] Johannes Gutenberg Univ Mainz, Inst Inorgan & Analyt Chem, Mainz, Germany. [d'Uston, Claude] Ctr Etud Spatiale Rayonnements 9, Toulouse, France. [Weitz, Catherine] Planetary Sci Inst, Tucson, AZ USA. [Yingst, R. Aileen] Univ Wisconsin, Nat & Appl Sci, Green Bay, WI 54302 USA. [Cohen, Barbara A.] Univ New Mexico, Dept Earth & Planetary Sci, Albuquerque, NM 87131 USA. [Franklin, Brenda; Anderson, Robert C.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Anderson, Robert C.; Li, Ron] Ohio State Univ, Ctr Mapping, CEEGS, Columbus, OH 43210 USA. RP Anderson, RC (reprint author), CALTECH, Jet Prop Lab, M-S 264-422,4800 Oak Grove Dr, Pasadena, CA 91109 USA. RI Schroder, Christian/B-3870-2009 OI Schroder, Christian/0000-0002-7935-6039 NR 38 TC 17 Z9 17 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9097 EI 2169-9100 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD MAY 17 PY 2008 VL 113 IS E6 AR E06S05 DI 10.1029/2007JE002953 PG 11 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 303TA UT WOS:000256062600001 ER PT J AU Zhang, ZF Hagfors, T Nielsen, E Picardi, G Mesdea, A Plaut, JJ AF Zhang, Zhenfei Hagfors, Tor Nielsen, Erling Picardi, Giovanni Mesdea, Arturo Plaut, Jeffrey J. TI Dielectric properties of the Martian south polar layered deposits: MARSIS data inversion using Bayesian inference and genetic algorithm SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID RADAR; SUBSURFACE; IONOSPHERE; SCATTERING; CAP; ORBITER; SURFACE AB Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS) has offered abundant data, which have been used to estimate dielectric properties of the south polar layered deposits (SPLD) of Mars. This paper presents a new way to invert the data to estimate the dielectric properties of the SPLD. A total of 4364 measurements were analyzed. The received radar signals are controlled by the physical properties of the SPLD and its basal layer and in addition by a number of factors including the transmitted wave properties, the satellite height, and the atmosphere/ionosphere environments. The received signals may also be influenced by surface clutter. Most of these factors are variable. This complexity causes the inversion to be difficult. To carry out the inversion, it is therefore essential to define a reasonably simple model for the physics of the surface/subsurface layers where the radar signal is reflected. The top and bottom interfaces of the SPLD are observed by MARSIS as two reflection peaks of the radar signals. The intensity ratio between the two reflection peaks is observed to be a function of the time difference separating the two peaks. By modeling this dependency, the influences of the satellite position and the atmosphere/ionosphere environments are canceled. This is a major step toward carrying out the inversion. Nevertheless, the inverse problem remains ill-posed and highly nonlinear. Bayesian inference is employed to deal with the ill-posed aspect of the inversion, and genetic algorithm is introduced to deal with the nonlinearity. It is concluded that the most probable value of the relative dielectric constant of the SPLD lies in 3.0-5.0, conductivity 1.0-2.0 x 10(-6) S/m, and the relative dielectric constant of the basal layer is 7.5-8.5 (The basal layer conductivity is assumed to be 1.0 x 10(-7) S/m.) These results support a suggestion that the SPLD are water ice/dust mixtures with dust content varying from 0 to more than 75%. C1 [Zhang, Zhenfei; Hagfors, Tor; Nielsen, Erling] Max Planck Inst Solar Syst Res, D-37191 Katlenburg Lindau, Germany. [Zhang, Zhenfei] China Univ Geosci, Dept Resources, Wuhan 430074, Peoples R China. [Zhang, Zhenfei] China Univ Geosci, Ctr Space Sci, Wuhan 430074, Peoples R China. [Picardi, Giovanni; Mesdea, Arturo] Univ Roma La Sapienza, Infocom Dept, I-00184 Rome, Italy. [Plaut, Jeffrey J.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Zhang, ZF (reprint author), Max Planck Inst Solar Syst Res, D-37191 Katlenburg Lindau, Germany. NR 32 TC 19 Z9 20 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD MAY 17 PY 2008 VL 113 IS E5 AR E05004 DI 10.1029/2007JE002941 PG 15 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 303SZ UT WOS:000256062500001 ER PT J AU Tsurutani, BT Verkhoglyadova, OP Mannucci, AJ Saito, A Araki, T Yumoto, K Tsuda, T Abdu, MA Sobral, JHA Gonzalez, WD McCreadie, H Lakhina, GS Vasyliunas, VM AF Tsurutani, B. T. Verkhoglyadova, O. P. Mannucci, A. J. Saito, A. Araki, T. Yumoto, K. Tsuda, T. Abdu, M. A. Sobral, J. H. A. Gonzalez, W. D. McCreadie, H. Lakhina, G. S. Vasyliunas, V. M. TI Prompt penetration electric fields (PPEFs) and their ionospheric effects during the great magnetic storm of 30-31 October 2003 SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID LOW-LATITUDE IONOSPHERE; EQUATORIAL IONOSPHERE; SUDDEN COMMENCEMENT; DISTURBANCE DYNAMO; GEOMAGNETIC STORM; SOLAR-WIND; JULY 15; MODEL; DENSITY; SYSTEM AB We explore the ionospheric effects of prompt penetration electric fields (PPEFs) for a variety of interplanetary magnetic field directions. We use the great magnetic storm of 30-31 October as an example of PPEF effects. For intense southward interplanetary magnetic fields (IMFs), inward plasma sheet convection occurs with the result of magnetospheric ring current formation and an intense magnetic storm. Concurrent with the above, positive phase ionospheric storms occur in the dayside, and negative phase ionospheric storms occur on the nightside, the topics of this paper. The dayside ionospheric storms due to PPEFs are characterized by transport of near-equatorial plasma to higher altitudes and latitudes, forming a giant plasma fountain. These features are part of what is called the dayside ionospheric superfountain (DIS). For these southward IMFs, dusk and dawn plasma are predicted to be transported toward the dayside. For northward IMFs, negative phase ionospheric storms are expected on the dayside if the PPEFs indeed reach that region of space. IMF By components are expected to have weak or neglible ionospheric effects. On the basis of PPEF arguments, intervals of IMF By should not be related to geomagnetic storms (they are not). IMF By intervals should, however, cause a shearing of the magnetotail, a feature that has been previously reported in the literature. C1 [Tsurutani, B. T.; Mannucci, A. J.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Tsurutani, B. T.; Verkhoglyadova, O. P.; Tsuda, T.] Kyoto Univ, RISH, Kyoto 6110011, Japan. [Verkhoglyadova, O. P.] Univ Calif Riverside, Inst Geophys & Planetary Phys, Riverside, CA 92521 USA. [Saito, A.; Araki, T.] Kyoto Univ, KUGI, Kyoto 6068502, Japan. [Yumoto, K.] Kyushu Univ, SERC, Fukuoka 8128581, Japan. [Abdu, M. A.; Sobral, J. H. A.; Gonzalez, W. D.] INPE, BR-12201970 Sao Paulo, Brazil. [McCreadie, H.] Univ Munich, Dept Earth & Environm Sci, D-80333 Munich, Germany. [Lakhina, G. S.] Indian Inst Geomagnetism, Bombay 400005, Maharashtra, India. [Vasyliunas, V. M.] Max Planck Inst Solar Syst Res, D-37191 Katlenburg Lindau, Germany. RP Tsurutani, BT (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM bruce.t.tsurutani@jpl.nasa.gov RI McCreadie, Heather/A-6446-2012; Lakhina, Gurbax /C-9295-2012; tsuda, toshitaka/A-3035-2015; U-ID, Kyushu/C-5291-2016; OI McCreadie, Heather/0000-0002-6433-0848; Lakhina, Gurbax /0000-0002-8956-486X; Verkhoglyadova, Olga/0000-0002-9295-9539 NR 62 TC 72 Z9 72 U1 1 U2 11 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAY 17 PY 2008 VL 113 IS A5 AR A05311 DI 10.1029/2007JA012879 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 303TH UT WOS:000256063300005 ER PT J AU Froidevaux, L Jiang, YB Lambert, A Livesey, NJ Read, WG Waters, JW Fuller, RA Marcy, TP Popp, PJ Gao, RS Fahey, DW Jucks, KW Stachnik, RA Toon, GC Christensen, LE Webster, CR Bernath, PF Boone, CD Walker, KA Pumphrey, HC Harwood, RS Manney, GL Schwartz, MJ Daffer, WH Drouin, BJ Cofield, RE Cuddy, DT Jarnot, RF Knosp, BW Perun, VS Snyder, WV Stek, PC Thurstans, RP Wagner, PA AF Froidevaux, L. Jiang, Y. B. Lambert, A. Livesey, N. J. Read, W. G. Waters, J. W. Fuller, R. A. Marcy, T. P. Popp, P. J. Gao, R. S. Fahey, D. W. Jucks, K. W. Stachnik, R. A. Toon, G. C. Christensen, L. E. Webster, C. R. Bernath, P. F. Boone, C. D. Walker, K. A. Pumphrey, H. C. Harwood, R. S. Manney, G. L. Schwartz, M. J. Daffer, W. H. Drouin, B. J. Cofield, R. E. Cuddy, D. T. Jarnot, R. F. Knosp, B. W. Perun, V. S. Snyder, W. V. Stek, P. C. Thurstans, R. P. Wagner, P. A. TI Validation of Aura Microwave Limb Sounder HCl measurements SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID HALOGEN OCCULTATION EXPERIMENT; IN-SITU MEASUREMENTS; EOS MLS; LOWER STRATOSPHERE; CHLORINE; MODEL; SPECTROMETER; RETRIEVAL; SATELLITE; PROFILES AB The Earth Observing System (EOS) Microwave Limb Sounder (MLS) aboard the Aura satellite has provided daily global HCl profiles since August 2004. We provide a characterization of the resolution, random and systematic uncertainties, and known issues for the version 2.2 MLS HCl data. The MLS sampling allows for comparisons with many (similar to 1500 to more than 3000) closely matched profiles from the Halogen Occultation Experiment (HALOE) and Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS). These data sets provide HCl latitudinal distributions that are, overall, very similar to those from (coincident) MLS profiles, although there are some discrepancies in the upper stratosphere between the MLS and HALOE gradients. As found in previous work, MLS and ACE HCl profiles agree very well (within similar to 5%, on average), but the MLS HCl abundances are generally larger (by 10-20%) than HALOE HCl. The bias versus HALOE is unlikely to arise mostly from MLS, as a similar systematic bias (of order 15%) is not observed between average MLS and balloon-borne measurements of HCl, obtained over Fort Sumner, New Mexico, in 2004 and 2005. At the largest pressure (147 hPa) for MLS HCl, a high bias (similar to 0.2 ppbv) is apparent in analyses of low to midlatitude data versus in situ aircraft chemical ionization mass spectrometry (CIMS) HCl measurements from the Aura Validation Experiment (AVE) campaigns in 2004, 2005, and 2006; this bias is also observed in comparisons of MLS and aircraft HCl/O-3 correlations. Good agreement between MLS and CIMS HCl is obtained at 100 to 68 hPa. The recommended pressure range for MLS HCl is from 100 to 0.15 hPa. C1 [Froidevaux, L.; Jiang, Y. B.; Lambert, A.; Livesey, N. J.; Read, W. G.; Waters, J. W.; Fuller, R. A.; Stachnik, R. A.; Toon, G. C.; Christensen, L. E.; Webster, C. R.; Manney, G. L.; Schwartz, M. J.; Daffer, W. H.; Drouin, B. J.; Cofield, R. E.; Cuddy, D. T.; Jarnot, R. F.; Knosp, B. W.; Perun, V. S.; Snyder, W. V.; Stek, P. C.; Thurstans, R. P.; Wagner, P. A.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Marcy, T. P.; Popp, P. J.; Gao, R. S.; Fahey, D. W.] NOAA, Earth Syst Res Lab, Boulder, CO 80305 USA. [Marcy, T. P.; Popp, P. J.] Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. [Jucks, K. W.] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. [Bernath, P. F.] Univ York, Dept Chem, York YO10 5DD, N Yorkshire, England. [Boone, C. D.; Walker, K. A.] Univ Waterloo, Dept Chem, Waterloo, ON N2L 3G1, Canada. [Walker, K. A.] Univ Toronto, Dept Phys, Toronto, ON, Canada. [Pumphrey, H. C.; Harwood, R. S.] Univ Edinburgh, Sch Geosci, Edinburgh EH9 3JW, Midlothian, Scotland. [Manney, G. L.] New Mexico Inst Min & Technol, Socorro, NM 87801 USA. RP Froidevaux, L (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM lucien.froidevaux@jpl.nasa.gov RI Manager, CSD Publications/B-2789-2015; Bernath, Peter/B-6567-2012; Gao, Ru-Shan/H-7455-2013; Schwartz, Michael/F-5172-2016; Fahey, David/G-4499-2013 OI Bernath, Peter/0000-0002-1255-396X; Schwartz, Michael/0000-0001-6169-5094; Fahey, David/0000-0003-1720-0634 NR 46 TC 28 Z9 29 U1 1 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 16 PY 2008 VL 113 IS D15 AR D15S25 DI 10.1029/2007JD009025 PG 23 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 303SQ UT WOS:000256061600002 ER PT J AU Shephard, MW Herman, RL Fisher, BM Cady-Pereira, KE Clough, SA Payne, VH Whiteman, DN Comer, JP Vomel, H Miloshevich, LM Forno, R Adam, M Osterman, GB Eldering, A Worden, JR Brown, LR Worden, HM Kulawik, SS Rider, DM Goldman, A Beer, R Bowman, KW Rodgers, CD Luo, M Rinsland, CP Lampel, M Gunson, MR AF Shephard, Mark W. Herman, Robert L. Fisher, Brendan M. Cady-Pereira, Karen E. Clough, Shepard A. Payne, Vivienne H. Whiteman, David N. Comer, Joseph P. Vomel, Holger Miloshevich, Larry M. Forno, Ricardo Adam, Mariana Osterman, Gregory B. Eldering, Annmarie Worden, John R. Brown, Linda R. Worden, Helen M. Kulawik, Susan S. Rider, David M. Goldman, Aaron Beer, Reinhard Bowman, Kevin W. Rodgers, Clive D. Luo, Mingzhao Rinsland, Curtis P. Lampel, Michael Gunson, Michael R. TI Comparison of Tropospheric Emission Spectrometer nadir water vapor retrievals with in situ measurements SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID AURA MISSION; DRY BIAS; TES AB Comparisons of Tropospheric Emission Spectrometer (TES) water vapor retrievals with in situ measurements are presented. Global comparisons of TES water vapor retrievals with nighttime National Centers for Environmental Prediction RS90/RS92 radiosondes show a small (<5%) moist bias in TES retrievals in the lower troposphere (standard deviation of similar to 20%), increasing to a maximum of similar to 15% bias (with standard deviation reaching similar to 40%) in the upper troposphere. This moist bias with respect to the sonde bias increases to a maximum of similar to 15% in the upper troposphere between similar to 300-200 hPa. The standard deviation in this region reaches values of similar to 40%. It is important to note that the TES reported water vapor comparison statistics are not weighted by the water vapor layer amounts. Global TES/radiosonde results are comparable with the Atmospheric Infrared Sounder reported unweighted mean of 25% and root-mean-square of similar to 55%. While such global comparisons help to identify general issues, inherent sampling errors and radiosonde measurement accuracy can limit the degree to which the radiosonde profiles alone can be used to validate satellite retrievals. In order to characterize the agreement of TES with in situ measurements in detail, radiance closure studies were performed using data from the Water Vapor Validation Experiment - Satellites/Sondes campaign from July 2006. Results indicate that estimated systematic errors from the forward model, TES measurements, in situ observations, retrieved temperature profiles, and clouds are likely not large enough to account for radiance differences between TES observations and forward model calculations using in situ profiles as input. Therefore, accurate validation of TES water vapor retrievals requires further campaigns with a larger variety of water vapor measurements that better characterize the atmospheric state within the TES field of view. C1 [Shephard, Mark W.; Cady-Pereira, Karen E.; Clough, Shepard A.; Payne, Vivienne H.] Atmospher & Environm Res Inc, Lexington, MA 02421 USA. [Herman, Robert L.; Fisher, Brendan M.; Osterman, Gregory B.; Eldering, Annmarie; Brown, Linda R.; Worden, Helen M.; Kulawik, Susan S.; Rider, David M.; Beer, Reinhard; Bowman, Kevin W.; Luo, Mingzhao; Gunson, Michael R.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Whiteman, David N.; Comer, Joseph P.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20740 USA. [Vomel, Holger] Natl Oceanog & Atmospher Adm, Boulder, CO 80305 USA. [Miloshevich, Larry M.] Natl Ctr Atmospher Res, Boulder, CO 80305 USA. [Forno, Ricardo] Univ Mayor de San Andres, La Paz 3165, Bolivia. [Adam, Mariana] Howard Univ, Washington, DC 20059 USA. [Goldman, Aaron] Univ Denver, Denver, CO 80208 USA. [Rodgers, Clive D.] Univ Oxford, Clarendon Lab, Oxford OX1 3PU, England. [Rinsland, Curtis P.] NASA, Langley Res Ctr, Hampton, VA 23681 USA. [Lampel, Michael] Raytheon Tech Serv Co, Pasadena, CA 91101 USA. RP Shephard, MW (reprint author), Atmospher & Environm Res Inc, 131 Hartwell Ave, Lexington, MA 02421 USA. EM mshephar@aer.com RI Payne, Vivienne/D-9713-2012; Herman, Robert/H-9389-2012; Adam, Mariana/C-5661-2013 OI Herman, Robert/0000-0001-7063-6424; NR 32 TC 26 Z9 26 U1 1 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 16 PY 2008 VL 113 IS D15 AR D15S24 DI 10.1029/2007JD008822 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 303SQ UT WOS:000256061600001 ER PT J AU Huete, AR Restrepo-Coupe, N Ratana, P Didan, K Saleska, SR Ichii, K Panuthai, S Gamo, M AF Huete, A. R. Restrepo-Coupe, N. Ratana, P. Didan, K. Saleska, S. R. Ichii, K. Panuthai, S. Gamo, M. TI Multiple site tower flux and remote sensing comparisons of tropical forest dynamics in Monsoon Asia SO AGRICULTURAL AND FOREST METEOROLOGY LA English DT Article DE AsiaFlux; remote sensing; MODIS E-VI; tropical forests; phenology ID DIFFERENCE VEGETATION INDEX; GROSS PRIMARY PRODUCTION; AMAZONIAN RAIN-FOREST; LIGHT-USE EFFICIENCY; EVERGREEN FOREST; DECIDUOUS FOREST; EASTERN AMAZONIA; LEAF PHENOLOGY; SATELLITE DATA; SOUTH-AMERICA AB The spatial and temporal dynamics of tropical forest functioning are poorly understood, partly attributed to a weak seasonality and high tree species diversity at the landscape scale. Recent neotropical rainforest studies with local tower flux measurements have revealed strong seasonal carbon fluxes that follow the availability of sunlight in intact forests, while in areas of forest disturbance, carbon fluxes more closely tracked seasonal water availability. These studies also showed a strong seasonal correspondence of satellite measures of greenness, using the Enhanced Vegetation index (E-VI) with ecosystem carbon fluxes in both intact and disturbed forests, which may enable larger scale extension of tower flux measurements. In this study, we investigated the seasonal patterns and relationships of local site tower flux measures of gross primary productivity (P-g) with independent Moderate Resolution Imaging Spectroradiometer (MODIS) satellite greenness measures across three Monsoon Asia tropical forest types, encompassing drought-deciduous, dry evergreen, and humid evergreen secondary tropical forests. In contrast to neotropical forests, the tropical forests of Monsoon Asia are more extensively degraded and heterogeneous due to intense land use pressures, and therefore, may exhibit unique seasonal patterns of ecosystem fluxes that are more likely water-limited and drought-susceptible. Our results show significant phenologic variability and response to moisture and light controls across the three tropical forest sites and at the regional scale. The drier tropical forests were primarily water-limited, while the wet evergreen secondary forest showed a slight positive trend with light availability. Satellite E-VI greenness observations were generally synchronized and linearly related with seasonal and inter-annual tower flux P-g measurements at the multiple sites and provided better opportunities for tower extension of carbon fluxes than other satellite products, such as the MODIS P-g product. Satellite E-VI-derived P-g images revealed strong seasonal variations in photosynthetic activity throughout the Monsoon Asia tropical region. (C) 2008 Elsevier B.V. All rights reserved. C1 [Huete, A. R.; Didan, K.] Univ Arizona, Dept Soil Water & Environm Sci, Tucson, AZ 85721 USA. [Restrepo-Coupe, N.; Saleska, S. R.] Univ Arizona, Dept Ecol & Evolutionary Biol, Tucson, AZ 85721 USA. [Huete, A. R.; Saleska, S. R.] Univ Arizona, Inst Study Planet Earth, Tucson, AZ 85721 USA. [Ratana, P.] Khon Kaen Univ, Dept Geotechnol, Khon Kaen, Thailand. [Ichii, K.] NASA, Ames Res Ctr, Ecosyst Sci & Technol Branch, Moffett Field, CA 94035 USA. [Ichii, K.] San Jose State Univ, Moffett Field, CA 94035 USA. [Panuthai, S.] Natl Pk, Wildlife & Plant Conservat Dept, Bangkok 10900, Thailand. [Gamo, M.] Natl Inst Adv industrial Sci & Technol, Tsukuba, Ibaraki 3058569, Japan. RP Huete, AR (reprint author), Univ Arizona, Dept Soil Water & Environm Sci, Tucson, AZ 85721 USA. EM ahuete@ag.arizona.edu RI Ichii, Kazuhito/D-2392-2010; Restrepo-Coupe, Natalia/C-3507-2015; Huete, Alfredo/C-1294-2008; OI Ichii, Kazuhito/0000-0002-8696-8084; Restrepo-Coupe, Natalia/0000-0003-3921-1772; Huete, Alfredo/0000-0003-2809-2376; Ratana, Piyachat/0000-0002-1853-2860 NR 66 TC 50 Z9 51 U1 6 U2 32 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-1923 EI 1873-2240 J9 AGR FOREST METEOROL JI Agric. For. Meteorol. PD MAY 15 PY 2008 VL 148 IS 5 BP 748 EP 760 DI 10.1016/j.agrformet.2008.01.012 PG 13 WC Agronomy; Forestry; Meteorology & Atmospheric Sciences SC Agriculture; Forestry; Meteorology & Atmospheric Sciences GA 312SS UT WOS:000256691700006 ER PT J AU Debaille, V Yin, QZ Brandon, AD Jacobsen, B AF Debaille, V. Yin, Q. -Z. Brandon, A. D. Jacobsen, B. TI Martian mantle mineralogy investigated by the Lu-176-Hf-176 and Sm-147-Nd-143 systematics of shergottites SO EARTH AND PLANETARY SCIENCE LETTERS LA English DT Article DE shergottites; Martian mantle; magma ocean; Hf isotopes ID ND ISOTOPIC SYSTEMATICS; TERRESTRIAL MAGMA OCEAN; LU-HF; HAFNIUM ISOTOPE; SM-ND; SNC METEORITES; CORE FORMATION; FRACTIONAL CRYSTALLIZATION; EARLY DIFFERENTIATION; CHEMICAL EVOLUTION AB Chemical heterogeneities in the Martian mantle are believed to result from the crystallization of a magma ocean in the first 100 million years of its history. Shergottite meteorites from Mars are thought to retain a compositional record of such early differentiation and the resulting mineralogy at different depths. The coupled Lu-176-Hf-176 and Sm-147-Nd-143 isotope systematics in 9 shergottites are used here to investigate these issues. Three compositional groups in the shergottites display distinct isotope systematics. One group, commonly termed as depleted, is characterized by positive epsilon Hf-176(i) from +46.2 to +50.4 and epsilon Nd-143(i) from +36.2 to +39.1. Another, termed as enriched, has negative epsilon Hf-176(i) = -16.5 to -13.2 and epsilon Nd-143(i)=-7.0 to -6.5. The third group is intermediate between the depleted and enriched groups with positive epsilon Hf-176(i)=+30.0 to +33.4 and epsilon Nd-143(i)=+16.9. Together, they describe mixing curves between Hf-176/Hf-177, Nd-143/Nd-144, Lu/Hf, and Sm/Nd, implying that they sample two distinct sources in the Martian mantle. All shergottites are characterized by (Sm/Nd)(source)<(Sm/Nd)(sample), but (Lu/Hf)(source)>(Lu/Hf)(sample). This decoupling can be explained by two successive partial melting episodes in the depleted shergottite source and localized in the Martian upper mantle. The genesis of shergottites can be modeled using non-modal equilibrium partial melting in a source initially composed of 60% olivine, 21% clinopyroxene, 9% orthopyroxene, and 10% garnet, with degrees of partial melting of 8.8% and 3.9%, respectively, for the two successive events. The enriched end-member of the shergottite mixing curve is best modeled by late-stage quenched residual melt resulting from the crystallization of a magma ocean. The depleted shergottite source may be modeled as a mixture of cumulates and residual melt, as convection in the Martian magma ocean is expected to reduce the incompatible trace element heterogeneity in the final solidified layers. Consequently, equilibrium crystallization is preferred to model the crystallization of the Martian magma ocean. The models that best explain the shergottite data are those where the magma ocean is at a depth of at least 1350 km in Mars. (C) 2008 Elsevier B.V. All rights reserved. C1 [Debaille, V.] Lunar & Planetary Inst, Houston, TX 77058 USA. [Yin, Q. -Z.; Jacobsen, B.] Univ Calif Davis, Dept Geol, Davis, CA 95616 USA. [Brandon, A. D.] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Debaille, V (reprint author), Free Univ Brussels, Dept Sci Terre Environm, CP 160-02,50 Av FD Roosevelt, B-1050 Brussels, Belgium. EM vinciane.debaille@ulb.ac.be RI Yin, Qing-Zhu/B-8198-2009 OI Yin, Qing-Zhu/0000-0002-4445-5096 NR 67 TC 49 Z9 49 U1 6 U2 18 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0012-821X EI 1385-013X J9 EARTH PLANET SC LETT JI Earth Planet. Sci. Lett. PD MAY 15 PY 2008 VL 269 IS 1-2 BP 186 EP 199 DI 10.1016/j.epsl.2008.02.008 PG 14 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 312XI UT WOS:000256705300017 ER PT J AU Jiang, X Waliser, DE AF Jiang, Xianan Waliser, Duane E. TI Northward propagation of the subseasonal variability over the eastern Pacific warm pool SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID SUMMER INTRASEASONAL OSCILLATION; MADDEN-JULIAN OSCILLATION; SOUTH ASIAN MONSOON; BOREAL SUMMER; MODEL; MECHANISMS; CONVECTION; SATELLITE; MJO AB Previous studies suggest that easterly vertical shear of summer mean flow could be a key factor in the northward propagation of the subseasonal variability (SSV) over the Asian monsoon region (e. g., Jiang et al., 2004). Analysis indicates that this same mechanism may also be dictating propagation features over the eastern Pacific (EPAC). Consistent with the presence of local easterly vertical wind shear, northward propagation of the SSV is also evident over the EPAC with a phase speed of about 0.6 deg day(-1). Moreover, similar to its counterpart in the Indian Ocean, the northward propagating SSV over this region is also characterized by positive anomalies of equivalent barotropic vorticity and lower-tropospheric specific humidity, and planetary boundary layer (PBL) convergence, to the north of the convection center. Thus, the present study provides another independent example of the essential role that easterly vertical wind shear may be playing in regulating the meridional migration of the SSV. C1 [Jiang, Xianan; Waliser, Duane E.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Jiang, X (reprint author), CALTECH, Jet Prop Lab, MS-183-501, Pasadena, CA 91109 USA. EM xianan@caltech.edu RI Jiang, Xianan/A-2283-2012 NR 31 TC 28 Z9 30 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 EI 1944-8007 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAY 15 PY 2008 VL 35 IS 9 AR L09814 DI 10.1029/2008GL033723 PG 6 WC Geosciences, Multidisciplinary SC Geology GA 303SD UT WOS:000256060300006 ER PT J AU Pritchard, ME Fielding, EJ AF Pritchard, M. E. Fielding, E. J. TI A study of the 2006 and 2007 earthquake sequence of Pisco, Peru, with InSAR and teleseismic data SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID NAZCA PLATE; SUBDUCTION; ZONE AB We combine interferometric synthetic aperture radar (InSAR) and teleseismic body waves to study the largest earthquake (M(w) 8.1) in a sequence of events on the subduction megathrust near Pisco, Peru. Our analysis includes some of the first InSAR data from the ALOS satellite and wide swath data from the Envisat satellite. The teleseismic data indicate the slip maximum occurred 60 90 seconds after the mainshock started. The InSAR data constrain the main slip patch to be about 70 km from the hypocenter, suggesting an extremely low rupture velocity (<1.5 km/s) or long slip rise time. No large earthquake has occurred in the 2007 rupture area since at least 1746 and possibly 1687, suggesting significant aseismic deformation in the area. The slip deficit apparently cannot be filled with rapid after-slip. In addition, the area where the Nazca Ridge is subducting appears to be either a seismic gap or a persistent area of aseismic slip. C1 [Pritchard, M. E.] Cornell Univ, Dept Earth & Atmospher Sci, Ithaca, NY 14853 USA. [Fielding, E. J.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Pritchard, ME (reprint author), Cornell Univ, Dept Earth & Atmospher Sci, Snee Hall, Ithaca, NY 14853 USA. EM pritchard@cornell.edu; eric.j.fielding@jpl.nasa.gov RI Pritchard, Matthew/L-5892-2015; Fielding, Eric/A-1288-2007 OI Pritchard, Matthew/0000-0003-3616-3373; Fielding, Eric/0000-0002-6648-8067 NR 21 TC 19 Z9 20 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAY 15 PY 2008 VL 35 IS 9 AR L09308 DI 10.1029/2008GL033374 PG 6 WC Geosciences, Multidisciplinary SC Geology GA 303SD UT WOS:000256060300002 ER PT J AU Park, Y King, GC Choi, SH AF Park, Yeonjoon King, Glen C. Choi, Sang H. TI Rhombohedral epitaxy of cubic SiGe on trigonal c-plane sapphire SO JOURNAL OF CRYSTAL GROWTH LA English DT Article DE crystal structure; single-crystal growth; polycrystalline deposition; semiconducting materials ID SILICON-ON-SAPPHIRE; MOLECULAR-BEAM EPITAXY; GROWTH-QUALITY; LAYERS; SUPERLATTICES; MOBILITY; PFETS; FILMS AB Highly [1 1 1]-oriented rhombohedral hetero-structure epitaxy of cubic SiGe semiconductor on trigonal c-plane sapphire was achieved and characterized with two new advanced X-ray diffraction methods to control the formation of primary-twin crystals. The formation of twin crystals on (1 1 1) plane was controlled with growth parameters such that the volume percentage of primary-twin crystal was reduced from 40% to 0.3% compared to the majority single crystal. The control of stacking faults can yield single-crystalline semiconductors without defects or improved thermoelectric materials with twinned crystals for phonon scattering while maintaining electrical integrity. In this study, about 94% of all epitaxial layers were fabricated in a single-crystalline phase. We propose the temperature-dependent alignment model of energetically favored majority single-crystalline SiGe layer on c-plane sapphire. This study shows that nearly single-crystalline cubic semiconductors can be grown in the [1 1 1] orientation on the basal (0 0 0 1) planes of selected trigonal crystal substrates. (C) 2008 Elsevier B.V. All rights reserved. C1 [Park, Yeonjoon] Natl Inst Aerosp, Hampton, VA 23666 USA. [King, Glen C.; Choi, Sang H.] NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Park, Y (reprint author), Natl Inst Aerosp, Hampton, VA 23666 USA. EM yeonjoon.park-1@nasa.gov NR 24 TC 10 Z9 10 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD MAY 15 PY 2008 VL 310 IS 11 BP 2724 EP 2731 DI 10.1016/j.jcrysgro.2008.02.010 PG 8 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 310BO UT WOS:000256504100007 ER PT J AU Cao, CY Xiong, XX Wu, AH Wu, XQ AF Cao, Changyong Xiong, Xiaoxiong Wu, Aisheng Wu, Xiangqian TI Assessing the consistency of AVHRR and MODIS L1B reflectance for generating fundamental climate data records SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SOLAR SPECTRAL IRRADIANCE; SOLSPEC SPECTROMETER; INFRARED CHANNELS; CALIBRATION; ATLAS; NM AB Satellite detection of the global climate change signals as small as a few percent per decade in albedo critically depends on consistent and accurately calibrated Level 1B (L1B) data or Fundamental Climate Data Records (FCDRs). Detecting small changes in signal over decades is a major challenge not only to the retrieval of geophysical parameters from satellite observations, but more importantly to the current state-of-the-art calibration, since such small changes can easily be obscured by erroneous variations in the calibration, especially for instruments with no onboard calibration, such as the Advanced Very High Resolution Radiometer (AVHRR). Without dependable FCDRs, its derivative Thematic Climate Data Records (TCDRs) are bound to produce false trends with questionable scientific value. This has been increasingly recognized by more and more remote sensing scientists. In this study we analyzed the consistency of calibrated reflectance from the operational L1B data between AVHRR on NOAA-16 and -17 and between NOAA-16/AVHRR and Aqua/MODIS, based on Simultaneous Nadir Overpass (SNO) observation time series. Analyses suggest that the NOAA-16 and -17/AVHRR operationally calibrated reflectance became consistent two years after the launch of NOAA-17, although they still differ by 9% from the MODIS reflectance for the 0.63 mm band. This study also suggests that the SNO method has reached a high level of relative accuracy (similar to 1.5%) for estimating the consistency for both the 0.63 and 0.84 mm bands between AVHRRs, and a 0.9% relative accuracy between AVHRR and MODIS for the 0.63 mm band. It is believed that the methodology is applicable to all historical AVHRR data for improving the calibration consistency, and work is in progress generating FCDRs from the nearly 30 years of AVHRR data using the SNO and other complimentary methods. A more consistent historical AVHRR L1B data set will be produced for a variety of geophysical products including aerosol, vegetation, cloud, and surface albedo to support global climate change detection studies. C1 [Cao, Changyong; Wu, Xiangqian] Off Res & Applicat, NOAA, NESDIS, Camp Springs, MD 20746 USA. [Wu, Aisheng] Sci Syst & Applicat Inc, Lanham, MD 20706 USA. [Xiong, Xiaoxiong] NASA, Goddard Space Flight Ctr, Sci Explorat Directorate Code 614 4, Greenbelt, MD 20771 USA. RP Cao, CY (reprint author), Off Res & Applicat, NOAA, NESDIS, E RA1,Room 810,WWB,5200 Auth Rd, Camp Springs, MD 20746 USA. EM changyong.cao@noaa.gov RI Cao, Changyong/F-5578-2010; Wu, Xiangqian/F-5634-2010 OI Wu, Xiangqian/0000-0002-7804-5650 NR 19 TC 45 Z9 47 U1 1 U2 8 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 15 PY 2008 VL 113 IS D9 AR D09114 DI 10.1029/2007JD009363 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 303SL UT WOS:000256061100004 ER PT J AU Rosenzweig, C Karoly, D Vicarelli, M Neofotis, P Wu, QG Casassa, G Menzel, A Root, TL Estrella, N Seguin, B Tryjanowski, P Liu, CZ Rawlins, S Imeson, A AF Rosenzweig, Cynthia Karoly, David Vicarelli, Marta Neofotis, Peter Wu, Qigang Casassa, Gino Menzel, Annette Root, Terry L. Estrella, Nicole Seguin, Bernard Tryjanowski, Piotr Liu, Chunzhen Rawlins, Samuel Imeson, Anton TI Attributing physical and biological impacts to anthropogenic climate change SO NATURE LA English DT Article ID LONG-TERM CHANGES; DISCONTINUOUS PERMAFROST; SURFACE CLIMATE; VARIABILITY; PHENOLOGY; PATTERN; RETREAT; TRENDS AB Significant changes in physical and biological systems are occurring on all continents and in most oceans, with a concentration of available data in Europe and North America. Most of these changes are in the direction expected with warming temperature. Here we show that these changes in natural systems since at least 1970 are occurring in regions of observed temperature increases, and that these temperature increases at continental scales cannot be explained by natural climate variations alone. Given the conclusions from the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report that most of the observed increase in global average temperatures since the mid-twentieth century is very likely to be due to the observed increase in anthropogenic greenhouse gas concentrations, and furthermore that it is likely that there has been significant anthropogenic warming over the past 50 years averaged over each continent except Antarctica, we conclude that anthropogenic climate change is having a significant impact on physical and biological systems globally and in some continents. C1 [Rosenzweig, Cynthia; Vicarelli, Marta; Neofotis, Peter] NASA, Goddard Inst Space Studies, New York, NY 10025 USA. [Rosenzweig, Cynthia; Vicarelli, Marta; Neofotis, Peter] Columbia Ctr Climate Syst Res, New York, NY 10025 USA. [Karoly, David] Univ Melbourne, Sch Earth Sci, Melbourne, Vic 3010, Australia. [Wu, Qigang] Univ Oklahoma, Sch Meteorol, Norman, OK 73019 USA. [Casassa, Gino] Ctr Estudios Cient, Valdivia, Chile. [Menzel, Annette; Estrella, Nicole] Tech Univ Munich, Ctr Life & Food Sci Weihenstephan, D-85354 Freising Weihenstephan, Germany. [Root, Terry L.] Stanford Univ, Ctr Environm Sci & Policy, Stanford, CA 94305 USA. [Seguin, Bernard] INRA Unite Agroclim, F-84914 Avignon 9, France. [Tryjanowski, Piotr] Adam Mickiewicz Univ, Dept Behav Ecol, Inst Environm Biol, PL-61614 Poznan, Poland. [Liu, Chunzhen] China Water Informat Ctr, Beijing 100761, Peoples R China. [Rawlins, Samuel] Caribbean Epidemiol Ctr, Port Of Spain, Trinid & Tobago. [Imeson, Anton] 3D Environm Change, NL-1851 AM Heiloo, Netherlands. RP Rosenzweig, C (reprint author), NASA, Goddard Inst Space Studies, 2800 Broadway, New York, NY 10025 USA. EM crosenzweig@giss.nasa.gov RI Tryjanowski, Piotr/C-1367-2009; Karoly, David/C-8262-2011; Menzel, Annette/B-1105-2013 OI Karoly, David/0000-0002-8671-2994; NR 39 TC 544 Z9 567 U1 34 U2 422 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 EI 1476-4687 J9 NATURE JI Nature PD MAY 15 PY 2008 VL 453 IS 7193 BP 353 EP U20 DI 10.1038/nature06937 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 301AI UT WOS:000255868400043 PM 18480817 ER PT J AU Saatchi, S Buermann, W Ter Steege, H Mori, S Smith, TB AF Saatchi, Sassan Buermann, Wolfgang Ter Steege, Hans Mori, Scott Smith, Thomas B. TI Modeling distribution of Amazonian tree species and diversity using remote sensing measurements SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE species distribution; remote sensing data; Maxent; Amazon basin; tree diversity ID VEGETATION LEAF-AREA; RANGE SIZE; VIROLA-SURINAMENSIS; GEOGRAPHIC RANGE; MODIS DATA; CONSERVATION; BIODIVERSITY; RICHNESS; PATTERNS; FORESTS AB The availability of a wide range of satellite measurements of environmental variables at different spatial and temporal resolutions, together with an increasing number of digitized and georeferenced species occurrences, has created the opportunity to model and monitor species geographic distribution and richness at regional to continental scales. In this paper, we examine the application of recently developed global data products from satellite observations in modeling the potential distribution of tree species and diversity in the Amazon basin. We use data from satellite sensors, including MODIS, QSCAT, SRTM, and TRMM, to develop different environmental variables related to vegetation, landscape, and climate. These variables are used in a maximum entropy method (Maxent) to model the geographical distribution of five commercial trees and to classify the patterns of tree alpha-diversity in the Amazon basin. Maxent simulations are analyzed using binomial tests of omission rates and the area under the receiver operating characteristics (ROC) curves to examine the model performance, the accuracy of geographic distributions, and the significance of environmental variables for discriminating suitable habitats. To evaluate the importance of satellite data, we used the Maxent jackknife test to quantify the training gains from data layers and to compare the results with model simulations using climate-only data. For all species and tree alpha-diversity, modeled distributions are in agreement with historical data and field observations. The results compare with climate-derived patterns, but provide better spatial resolution and detailed information on the habitat characteristics. Among satellite data products, QSCAT backscatter, representing canopy moisture and roughness, and MODIS leaf area index (LAI) are the most important variables in almost all cases. Model simulations suggest that climate and remote sensing results are complementary and that the best distribution patterns can be achieved when the two data sets are combined. (C) 2008 Elsevier Inc. All rights reserved. C1 [Saatchi, Sassan] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Buermann, Wolfgang] Univ Calif Los Angeles, Ctr Trop Res, Inst Environm, Los Angeles, CA 90095 USA. [Ter Steege, Hans] Univ Utrecht, Inst Environm Biol, Sect Plant Ecol & Biodivers, NL-3584 CA Utrecht, Netherlands. [Mori, Scott] New York Bot Garden, Bronx, NY 10458 USA. [Smith, Thomas B.] Univ Calif Los Angeles, Ctr Trop Res, Inst Environm, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, Dept Ecol & Evolutionary Biol, Los Angeles, CA 90095 USA. RP Saatchi, S (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM saatchi@congo.jpl.nasa.gov RI ter Steege, Amaz/B-5866-2011 OI ter Steege, Amaz/0000-0002-8738-2659 NR 61 TC 78 Z9 90 U1 9 U2 64 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0034-4257 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD MAY 15 PY 2008 VL 112 IS 5 BP 2000 EP 2017 DI 10.1016/j.rse.2008.01.008 PG 18 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 293YG UT WOS:000255370700008 ER PT J AU Chopping, M Moisen, GG Su, LH Laliberte, A Rango, A Martonchik, JV Peters, DPC AF Chopping, Mark Moisen, Gretchen G. Su, Lihong Laliberte, Andrea Rango, Albert Martonchik, John V. Peters, Debra P. C. TI Large area mapping of southwestern forest crown cover, canopy height, and biomass using the NASA Multiangle Imaging Spectro-Radiometer SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE forest; biomass; carbon; canopy; structure; BRDF; multiangle; geometric-optical; model ID REMOTE-SENSING DATA; BIDIRECTIONAL REFLECTANCE; MODEL; MISR; SURFACES AB A rapid canopy reflectance model inversion experiment was performed using multi-angle reflectance data from the NASA Multi-angle Imaging Spectro-Radiometer (MISR) on the Earth Observing System Terra satellite, with the goal of obtaining measures of forest fractional crown cover, mean canopy height, and aboveground woody biomass for large parts of south-eastern Arizona and southern New Mexico (>200,000 km(2)). MISR red band bidirectional reflectance estimates in nine views mapped to a 250 in grid were used to adjust the Simple Geometric-optical Model (SGM). The soil-understory background signal was partly decoupled a priori by developing regression relationships with the nadir camera blue, green, and near-infrared reflectance data and the isotropic, geometric, and volume scattering kernel weights of the LiSparse-RossThin kernel-driven bidirectional reflectance distribution function (BRDF) model adjusted against MISR red band data. The SGM's mean crown radius and crown shape parameters were adjusted using the Praxis optimization algorithm, allowing retrieval of fractional crown cover and mean canopy height, and estimation of aboveground woody biomass by linear rescaling of the dot product of cover and height. Retrieved distributions of crown cover, mean canopy height, and aboveground woody biomass for forested areas showed good matches with maps from the United States Department of Agriculture (USDA) Forest Service, with R-2 values of 0.78, 0.69, and 0.81, and absolute mean errors of 0.10, 2.2 m, and 4.5 tons acre(-1) (10.1 Mg ha(-1)), respectively, after filtering for high root mean square error (RMSE) on model fitting, the effects of topographic shading, and the removal of a small number of outliers. This is the first use of data from the MISR instrument to produce maps of crown cover, canopy height, and woody biomass over a large area by seeking to exploit the structural effects of canopies reflected in the observed anisotropy patterns in these explicitly multiangle data. (C) 2008 Elsevier Inc. All rights reserved. C1 [Chopping, Mark; Su, Lihong] Montclair State Univ, Dept Earth & Environm Studies, Montclair, NJ 07043 USA. [Moisen, Gretchen G.] US Forest Serv, USDA, Rocky Mt Res Stn, Ogden, UT 84401 USA. [Laliberte, Andrea; Rango, Albert; Peters, Debra P. C.] USDA ARS, Las Cruces, NM 88003 USA. [Martonchik, John V.] NASA, Jet Prop Lab, Pasadena, CA 91109 USA. RP Chopping, M (reprint author), Montclair State Univ, Dept Earth & Environm Studies, Montclair, NJ 07043 USA. EM chopping@pegasus.montelair.edu NR 28 TC 67 Z9 70 U1 3 U2 23 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0034-4257 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD MAY 15 PY 2008 VL 112 IS 5 BP 2051 EP 2063 DI 10.1016/j.rse.2007.07.024 PG 13 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 293YG UT WOS:000255370700011 ER PT J AU Simard, M Rivera-Monroy, VH Mancera-Pineda, JE Castaneda-Moya, E Twilley, RR AF Simard, Marc Rivera-Monroy, Victor H. Mancera-Pineda, Jose Ernesto Castaneda-Moya, Edward Twilley, Robert R. TI A systematic method for 3D mapping of mangrove forests based on Shuttle Radar Topography Mission elevation data, ICEsat/GLAS waveforms and field data: Application to Cienaga Grande de Santa Marta, Colombia SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE radar; SRTM; lidar; ICEsat; GLAS; mangroves; mangrove; wetlands; forest; height; waveforms ID TROPICAL ESTUARINE LAGOON; LARGE-FOOTPRINT LIDAR; CARIBBEAN COAST; POPULATION-DYNAMICS; BIOMASS; CANOPY; HEIGHT; RESTORATION; ECOSYSTEMS; IKONOS AB Mangrove forests are found within the intertropical zone and are one of the most biodiverse and productive wetlands on Earth. We focus oil the Cienaga Grande de Santa Marta (CGSM) in Colombia, the largest coastal lagoon-delta ecosystem in the Caribbean area with an extension of 1280 kin 2, where one of the largest mangrove rehabilitation projects in Latin America is currently underway. Extensive man-made hydrological modifications in the region caused hypersaline soil (>90 g kg(-1)) conditions since the 1960s triggering a large dieback of mangrove wetlands (similar to 247 km(2)). In this paper, we describe a new systematic methodology to measure mangrove height and aboveground biomass by remote sensing. The method is based on SRTM (Shuttle Radar Topography Mission) elevation data, ICEsat/GLAS waveforms (Ice, Cloud, and Land Elevation Satellite/Geoscience Laser Altimeter System) and field data. Since the locations of the ICEsat and field datasets do not coincide, they are used independently to calibrate SRTM elevation and produce a map of mangrove canopy height. We compared height estimation methods based on waveform centroids and the canopy height profile (CHP). Linear relationships between ICEsat height estimates and SRTM elevation were derived. We found the centroid of the canopy waveform contribution (CWC) to be the best height estimator. The field data was used to estimate a SRTM canopy height bias (-1.3 m) and estimation error (rms = 1.9 m). The relationship was applied to the SRTM elevation data to produce a mangrove canopy height map. Finally, we used field data and published allometric equations to derive an empirical relationship between canopy height and biomass. This relationship was used to scale the mangrove height map and estimate aboveground biomass distribution for the entire CGSM. The mean mangrove canopy height in CGSM is 7.7 m and most of the biomass is concentrated in forests around 9 m in height. Our biomass maps will enable estimation of regeneration rates of mangrove forests under hydrological rehabilitation at large spatial scales over the next decades. They will also be used to assess how highly disturbed mangrove forests respond to increasing sea level rise under current global climate change scenarios. (C) 2008 Elsevier Inc. All rights reserved. C1 [Simard, Marc] Jet Prop Lab, Pasadena, CA 91109 USA. [Rivera-Monroy, Victor H.; Castaneda-Moya, Edward; Twilley, Robert R.] Louisiana State Univ, Wetland Biogeochem Inst, Baton Rouge, LA 70803 USA. [Mancera-Pineda, Jose Ernesto] Univ Nacl Colombia, San Andres, Colombia. RP Simard, M (reprint author), Jet Prop Lab, MS 300-319D, Pasadena, CA 91109 USA. EM marc.simard@jpl.nasa.gov; vhrivera@lsu.edu; jemancerap@unal.edu.co RI Rivera-Monroy, Victor/G-7329-2011; Simard, Marc/H-3516-2013 OI Simard, Marc/0000-0002-9442-4562 NR 53 TC 61 Z9 72 U1 5 U2 53 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0034-4257 EI 1879-0704 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD MAY 15 PY 2008 VL 112 IS 5 BP 2131 EP 2144 DI 10.1016/j.rse.2007.10.012 PG 14 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 293YG UT WOS:000255370700017 ER PT J AU Brown, ME de Beurs, KM AF Brown, Molly E. de Beurs, Kirsten M. TI Evaluation of multi-sensor semi-arid crop season parameters based on NDVI and rainfall SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE start of season; semi-arid ecosystem; land surface phenology; MODIS; SPOT; GIMMS AVHRR; relative humidity ID VEGETATION INDEXES; REANALYSIS; PHENOLOGY; MODIS; CLASSIFICATION; LATITUDE; IMAGERY; AFRICA; MODEL AB Metrics that estimate the beginning of the growing season in semi-arid monsoonal ecosystems have become a central part of both crop models that are used to monitor crop production using satellite remote sensing and early warning indicators of possible future reductions in yield due to growing season length. This paper presents a new phenological model which is tuned to the semi-arid, monsoonal ecosystem of the West African Sahel and that uses humidity instead of calendar dates to identify the beginning of the season. We implement this model on vegetation index data from AVHRR, SPOT-Vegetation and MODIS data, and evaluate the results along with a rainfall-based start of season estimate for the region. Contributions of the paper include evaluating existing methods using ground observations of sowing date, comparing the same metric across multiple sensors and to rainfall-based SOS, and the development of a metric based on NDVI and relative humidity. (C) 2007 Elsevier Inc, All rights reserved. C1 [Brown, Molly E.] NASA, Goddard Space Flight Ctr, SSAI, Biospher Sci Branch, Greenbelt, MD 20771 USA. [de Beurs, Kirsten M.] Virginia Polytech Inst & State Univ, Dept Geog, Blacksburg, VA 24061 USA. RP Brown, ME (reprint author), NASA, Goddard Space Flight Ctr, SSAI, Biospher Sci Branch, Greenbelt, MD 20771 USA. EM molly.brown@nasa.gov; kdebeurs@vt.edu RI Brown, Molly/E-2724-2010; Brown, Molly/M-5146-2013 OI Brown, Molly/0000-0001-7384-3314; Brown, Molly/0000-0001-7384-3314 NR 38 TC 63 Z9 64 U1 2 U2 33 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0034-4257 EI 1879-0704 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD MAY 15 PY 2008 VL 112 IS 5 BP 2261 EP 2271 DI 10.1016/j.rse.2007.10.008 PG 11 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 293YG UT WOS:000255370700027 ER PT J AU Gordon, HR Franz, BA AF Gordon, Howard R. Franz, Bryan A. TI Remote sensing of ocean color: Assessment of the water-leaving radiance bidirectional effects on the atmospheric diffuse transmittance for SeaWiFS and MODIS intercomparisons SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE ocean color; diffuse transmittance; bidirectionality; SeaWIFS; MODIS ID REFLECTANCE; SCANNER; SYSTEM AB The portion of the radiance exiting the ocean and transmitted to the top of the atmosphere (TOA) in a particular direction depends on the angular distribution of the exiting radiance, not just the radiance exiting in the direction of interest. The diffuse transmittance t relates the water component of the TOA radiance to that exiting the water in the same direction. As such t is a property of the ocean-atmosphere system and not just the atmosphere. Its computation requires not only the properties of the atmosphere but the angular distribution of the exiting radiance as well. The latter is not known until a determination of the water properties can be made (which is the point of measuring the radiance in the first place). Because of this, it has been customary to assume an angular distribution (uniform upward radiance beneath the water surface) in the computation of t, which is referred to as t*. However, it is known that replacing t with t* can result in an error of several percent in the retrieved water-leaving radiance. Since the error depends on sun-viewing direction, this error could be particularly important when water-leaving radiance from two or more sensors in different orbits are compared. Even given an estimate of the angular distribution of the water-leaving radiance, computation of t using full radiative transfer theory in an image processing environment is not practical. Thus, we developed a first-order correction to t for bidirectional effects in the water-leaving radiance that captures much of the variability of t with viewing direction. The correction computed across a SeaWiFS scan line shows that a t*-induced error of as much as 5-6% could occur near the edges of the scan; however, limiting the scan to polar viewing angles (0) < 60 degrees reduces the error to similar to 1%. Direct application to SeaWTFS and MODIS (AQUA) suggests that the bidirectionally-induced error in the diffuse transmittance will result in an error less than about 1% in the comparison of their normalized water-leaving radiances, as long as theta is less than about 60 degrees. We conclude that, given this constraint, the nonnalized water-leaving retrievals from these two sensors at a given location can be merged without regard for the bidirectionally-induced error in the diffuse transmittance, as the resulting uncertainty is well below that from other sources. It is important to note that this result is likely to apply to any other polar-orbiting sensor with equatorial crossing times (similar to SeaWiFS and MODIS) between 1030 and 1330 h (local time). (C) 2008 Elsevier Inc. All rights reserved. C1 [Gordon, Howard R.] Univ Miami, Dept Phys, Coral Gables, FL 33124 USA. [Franz, Bryan A.] NASA, SAIC, Ocean Biol Proc Grp, GSFC, Greenbelt, MD 20771 USA. RP Gordon, HR (reprint author), Univ Miami, Dept Phys, Coral Gables, FL 33124 USA. EM gordon@physics.miami.edu RI Franz, Bryan/D-6284-2012 OI Franz, Bryan/0000-0003-0293-2082 NR 14 TC 10 Z9 10 U1 0 U2 7 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0034-4257 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD MAY 15 PY 2008 VL 112 IS 5 BP 2677 EP 2685 DI 10.1016/j.rse.2007.12.010 PG 9 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 293YG UT WOS:000255370700058 ER PT J AU Schroeder, W Prins, E Giglio, L Csiszar, I Schmidt, C Morisette, J Morton, D AF Schroeder, Wilfrid Prins, Elaine Giglio, Louis Csiszar, Ivan Schmidt, Christopher Morisette, Jeffrey Morton, Douglas TI Validation of GOES and MODIS active fire detection products using ASTER and ETM plus data SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE vegetation fires; Amazonia; MODIS; GOES; ASTER; ETM ID VEGETATION FIRE; SOUTHERN AFRICA; EMISSIONS; ALGORITHM; AMAZONIA; AMERICA; FORESTS; TRENDS; BRAZIL; 1ST AB In this study we implemented a comprehensive analysis to validate the MODIS and GOES satellite active fire detection products (MOD 14 and WFABBA, respectively) and characterize their major sources of omission and commission errors which have important implications for a large community of fire data users. Our analyses were primarily based on the use of 30 m resolution ASTER and ETM+ imagery as our validation data. We found that at the 50% true positive detection probability mark, WFABBA requires four times more active fire area than is necessary for MOD14 to achieve the same probability of detection, despite the 16x factor separating the nominal spatial resolutions of the two products. Approximately 75% and 95% of all fires sampled were omitted by the MOD14 and WFABBA instantaneous products, respectively; whereas an omission error of 38% was obtained for WFABBA when considering the 30-minute interval of the GOES data. Commission errors for MOD] 4 and WFABBA were found to be similar and highly dependent on the vegetation conditions of the areas imaged, with the larger commission errors (approximately 35%) estimated over regions of active deforestation. Nonetheless, the vast majority (>80%) of the commission errors were indeed associated with recent burning activity where scars could be visually confirmed in the higher resolution data. Differences in thermal dynamics of vegetated and non-vegetated areas were found to produce a reduction of approximately 50% in the commission errors estimated towards the hours of maximum fire activity (i.e., early-afternoon hours) which coincided with the MODIS/Aqua overpass. Lastly, we demonstrate the potential use of temporal metrics applied to the mid-infrared bands of MODIS and GOES data to reduce the commission errors found with the validation analyses. (C) 2008 Elsevier Inc. All rights reserved. C1 [Schroeder, Wilfrid; Csiszar, Ivan; Morton, Douglas] Univ Maryland, Dept Geog, College Pk, MD 20742 USA. [Prins, Elaine; Schmidt, Christopher] Univ Wisconsin, Cooperat Inst Meteorol Satellite Studies, Madison, WI 53706 USA. [Giglio, Louis] Sci Syst & Applicat Inc, Lanham, MD 20706 USA. [Morisette, Jeffrey] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Schroeder, W (reprint author), Univ Maryland, Dept Geog, 2181 LeFrak Hall, College Pk, MD 20742 USA. EM schroeder@hermes.geog.umd.edu RI Csiszar, Ivan/D-2396-2010; Schroeder, Wilfrid/F-6738-2010; Morton, Douglas/D-5044-2012 NR 39 TC 109 Z9 112 U1 2 U2 30 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0034-4257 EI 1879-0704 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD MAY 15 PY 2008 VL 112 IS 5 BP 2711 EP 2726 DI 10.1016/j.rse.2008.01.005 PG 16 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 293YG UT WOS:000255370700061 ER PT J AU Hayes, A Aharonson, O Callahan, P Elachi, C Gim, Y Kirk, R Lewis, K Lopes, R Lorenz, R Lunine, J Mitchell, K Mitri, G Stofan, E Wall, S AF Hayes, A. Aharonson, O. Callahan, P. Elachi, C. Gim, Y. Kirk, R. Lewis, K. Lopes, R. Lorenz, R. Lunine, J. Mitchell, K. Mitri, G. Stofan, E. Wall, S. TI Hydrocarbon lakes on Titan: Distribution and interaction with a porous regolith SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID SURFACE AB Synthetic Aperture Radar (SAR) images of Titan's north polar region reveal quasi-circular to complex features which are interpreted to be liquid hydrocarbon lakes. We investigate methane transport in Titan's hydrologic cycle using the global distribution of lake features. As of May 2007, the SAR data set covers similar to 22% of the surface and indicates multiple lake morphologies which are correlated across the polar region. Lakes are limited to latitudes above 55 degrees N and vary from < 10 to more than 100,000 km(2). The size and location of lakes provide constraints on parameters associated with subsurface transport. Using porous media properties inferred from Huygens probe observations, timescales for flow into and out of observed lakes are shown to be in the tens of years, similar to seasonal cycles. Derived timescales are compared to the time between collocated SAR observations in order to consider the role of subsurface transport in Titan's hydrologic cycle. C1 [Hayes, A.; Aharonson, O.; Lewis, K.] CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA. [Callahan, P.; Elachi, C.; Gim, Y.; Lopes, R.; Mitchell, K.; Mitri, G.; Wall, S.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Lorenz, R.] Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. [Kirk, R.] US Geol Survey, Flagstaff, AZ 86001 USA. [Lunine, J.] Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. [Stofan, E.] Proxemy Res, Laytonville, MD 20882 USA. RP Hayes, A (reprint author), CALTECH, Div Geol & Planetary Sci, MC 150-21, Pasadena, CA 91125 USA. EM hayes@gps.caltech.edu RI Lewis, Kevin/E-5557-2012; Hayes, Alexander/P-2024-2014; Lorenz, Ralph/B-8759-2016; Lopes, Rosaly/D-1608-2016 OI Hayes, Alexander/0000-0001-6397-2630; Lorenz, Ralph/0000-0001-8528-4644; Lopes, Rosaly/0000-0002-7928-3167 NR 9 TC 122 Z9 123 U1 2 U2 14 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAY 14 PY 2008 VL 35 IS 9 AR L09204 DI 10.1029/2008GL033409 PG 6 WC Geosciences, Multidisciplinary SC Geology GA 303SC UT WOS:000256060200001 ER PT J AU Santee, ML Lambert, A Read, WG Livesey, NJ Manney, GL Cofield, RE Cuddy, DT Daffer, WH Drouin, BJ Froidevaux, L Fuller, RA Jarnot, RF Knosp, BW Perun, VS Snyder, WV Stek, PC Thurstans, RP Wagner, PA Waters, JW Connor, B Urban, J Murtagh, D Ricaud, P Barret, B Kleinbohl, A Kuttippurath, J Kullmann, H von Hobe, M Toon, GC Stachnik, RA AF Santee, M. L. Lambert, A. Read, W. G. Livesey, N. J. Manney, G. L. Cofield, R. E. Cuddy, D. T. Daffer, W. H. Drouin, B. J. Froidevaux, L. Fuller, R. A. Jarnot, R. F. Knosp, B. W. Perun, V. S. Snyder, W. V. Stek, P. C. Thurstans, R. P. Wagner, P. A. Waters, J. W. Connor, B. Urban, J. Murtagh, D. Ricaud, P. Barret, B. Kleinboehl, A. Kuttippurath, J. Kuellmann, H. von Hobe, M. Toon, G. C. Stachnik, R. A. TI Validation of the Aura Microwave Limb Sounder ClO measurements SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID STRATOSPHERE; OZONE; MLS; ANTARCTICA; SATELLITE; MISSION; MODEL AB We assess the quality of the version 2.2 (v2.2) ClO measurements from the Microwave Limb Sounder (MLS) on the Earth Observing System Aura satellite. The MLS v2.2 ClO data are scientifically useful over the range 100 to 1 hPa, with a single- profile precision of similar to 0.1 ppbv throughout most of the vertical domain. Vertical resolution is similar to 3-4 km. Comparisons with climatology and correlative measurements from a variety of different platforms indicate that both the amplitude and the altitude of the peak in the ClO profile in the upper stratosphere are well determined by MLS. The latitudinal and seasonal variations in the ClO distribution in the lower stratosphere are also well determined, but a substantial negative bias is present in both daytime and nighttime mixing ratios at retrieval levels below (i. e., pressures larger than) 22 hPa. Outside of the winter polar vortices, this negative bias can be eliminated by subtracting gridded or zonal mean nighttime values from the individual daytime measurements. In studies for which knowledge of lower stratospheric ClO mixing ratios inside the winter polar vortices to better than a few tenths of a ppbv is needed, however, day - night differences are not recommended and the negative bias must be corrected for by subtracting the estimated value of the bias from the individual measurements at each affected retrieval level. C1 [Santee, M. L.; Lambert, A.; Read, W. G.; Livesey, N. J.; Manney, G. L.; Cofield, R. E.; Cuddy, D. T.; Daffer, W. H.; Drouin, B. J.; Froidevaux, L.; Fuller, R. A.; Jarnot, R. F.; Knosp, B. W.; Perun, V. S.; Snyder, W. V.; Stek, P. C.; Thurstans, R. P.; Wagner, P. A.; Waters, J. W.; Kleinboehl, A.; Toon, G. C.; Stachnik, R. A.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Ricaud, P.; Barret, B.] CNRS, Observ Midi Pyrenees, Lab Aerol, F-31400 Toulouse, France. [Connor, B.] Natl Inst Water & Atmospher Res, Omakau, Central Otago, New Zealand. [Kuellmann, H.] Univ Bremen, Inst Environm Phys, Bremen, Germany. [Manney, G. L.] New Mexico Inst Min & Technol, Dept Phys, Socorro, NM 87801 USA. [Urban, J.; Murtagh, D.] Chalmers, Dept Radio & Space Sci, SE-41296 Gothenburg, Sweden. [von Hobe, M.] Forschungszentrum Julich, Inst Chem & Dynam Geosphare Stratosphare 1, D-52425 Julich, Germany. RP Santee, ML (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM mls@mls.jpl.nasa.gov RI Barret, Brice/I-9350-2012; von Hobe, Marc/A-7969-2013; Urban, Jo/F-9172-2010; Murtagh, Donal/F-8694-2011; OI Barret, Brice/0000-0002-1784-4758; Urban, Jo/0000-0001-7026-793X; Murtagh, Donal/0000-0003-1539-3559; Kuttippurath, Jayanarayanan/0000-0003-4073-8918 NR 38 TC 39 Z9 39 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 14 PY 2008 VL 113 IS D15 AR D15S22 DI 10.1029/2007JD008762 PG 20 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 303SP UT WOS:000256061500002 ER PT J AU Sneep, M de Haan, JF Stammes, P Wang, P Vanbauce, C Joiner, J Vasilkov, AP Levelt, PF AF Sneep, M. de Haan, J. F. Stammes, P. Wang, P. Vanbauce, C. Joiner, J. Vasilkov, A. P. Levelt, P. F. TI Three-way comparison between OMI and PARASOL cloud pressure products SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ROTATIONAL RAMAN-SCATTERING; OZONE-MONITORING INSTRUMENT; BACKSCATTER ULTRAVIOLET MEASUREMENTS; ABSORPTION CROSS-SECTIONS; SURFACE REFLECTIVITY; OXYGEN; POLDER; RETRIEVAL; NM; CALIBRATION AB The cloud pressures determined by three different algorithms, operating on reflectances measured by two spaceborne instruments in the "A'' train, are compared with each other. The retrieval algorithms are based on absorption in the oxygen A-band near 765 nm, absorption by a collision induced absorption in oxygen near 477 nm, and the filling in of Fraunhofer lines by rotational Raman scattering near 350 nm. A Lambertian reflector as cloud model is assumed in the retrievals. The first algorithm operates on data collected by the POLDER instrument on board PARASOL, while the latter two operate on data from the OMI instrument on board EOS-Aura. The satellites sample the same air mass within about 15 min. We compare the retrieval algorithms using synthetic spectra to give the comparison realistic baseline expectations. It appears that these cloud pressures are not the pressure of the cloud top, but of a level inside the cloud. This is corroborated by comparisons with MODIS and CloudSat data: while the top of the cloud is seen by MODIS using emitted IR radiation, both OMI and PARASOL algorithms retrieve a pressure near the midlevel of the cloud. The three cloud pressure products are compared using 1 month of data. The cloud pressures are found to show a similar behavior, with correlation coefficients larger than 0.85 between the data sets for high effective cloud fractions. The average differences in the cloud pressure are small, between 2 and 45 hPa, for the whole data set, with an RMS difference of 65 to 93 hPa. This falls within the science requirement for the OMI cloud pressure to have an accuracy of 100 hPa. For small to medium effective cloud fractions, the cloud pressure distribution found by PARASOL is very similar to that found by OMI using the O-2-O-2 absorption. Somewhat larger differences are found for very high effective cloud fractions. C1 [Sneep, M.; de Haan, J. F.; Stammes, P.; Wang, P.; Levelt, P. F.] Royal Netherlands Meteorol Inst, Climate Res & Seismol Dept, NL-3730 AE De Bilt, Netherlands. [Joiner, J.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Vanbauce, C.] Univ Sci & Technol Lille, Opt Atmospher Lab, F-59655 Villeneuve Dascq, France. [Vasilkov, A. P.] Sci Syst & Applicat Inc, Lanham, MD 20706 USA. RP Sneep, M (reprint author), Royal Netherlands Meteorol Inst, Climate Res & Seismol Dept, POB 201, NL-3730 AE De Bilt, Netherlands. EM maarten.sneep@knmi.nl; stammes@knmi.nl; claudine.vanbauce@loa.univ-lille1.fr; joanna.joiner@nasa.gov RI Joiner, Joanna/D-6264-2012 NR 41 TC 53 Z9 53 U1 2 U2 11 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 14 PY 2008 VL 113 IS D15 AR D15S23 DI 10.1029/2007JD008694 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 303SP UT WOS:000256061500001 ER PT J AU Malone, CP Johnson, PV McConkey, JW Ajello, JM Kanik, I AF Malone, C. P. Johnson, P. V. McConkey, J. W. Ajello, J. M. Kanik, I. TI Dissociative excitation of N2O by electron impact SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Article ID EMISSION CROSS-SECTION; EXTREME-ULTRAVIOLET EMISSION; VACUUM-ULTRAVIOLET; MOLECULAR-HYDROGEN; MEDIUM-RESOLUTION; ATOMIC OXYGEN; IONIZATION; N-2; STATE; NM AB Vacuum ultraviolet emissions following electron impact dissociative excitation of N2O have been studied over the wavelength range 80-180 nm and for electron energies from threshold up to 300 eV. Calibrated spectral data are presented at 100 eV incident energy. The dominant NI (2p(34)S degrees-3s P-4) multiplet at 120.0 nm has a measured maximum cross section of (2.2 +/- 0.4) x 10(-18) cm(2) at 100 eV, which in turn was used to normalize 100 eV cross sections for all observed spectral features. In addition, excitation functions corresponding to the dominant emission features have been analysed in detail with particular emphasis on the near-threshold region. Possible dissociation channels are discussed. C1 [Malone, C. P.; Johnson, P. V.; McConkey, J. W.; Ajello, J. M.; Kanik, I.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [McConkey, J. W.] Univ Windsor, Dept Phys, Windsor, ON N9B 3P4, Canada. RP Malone, CP (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. RI Malone, Charles/A-6294-2010; Johnson, Paul/D-4001-2009 OI Malone, Charles/0000-0001-8418-1539; Johnson, Paul/0000-0002-0186-8456 NR 41 TC 7 Z9 7 U1 0 U2 6 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0953-4075 EI 1361-6455 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD MAY 14 PY 2008 VL 41 IS 9 AR 095201 DI 10.1088/0953-4075/41/9/095201 PG 9 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 298BI UT WOS:000255660800006 ER PT J AU Hui, WJ Cook, BI Ravi, S Fuentes, JD D'Odorico, P AF Hui, Wanching Jacquie Cook, Benjamin I. Ravi, Sujith Fuentes, Jose D. D'Odorico, Paolo TI Dust-rainfall feedbacks in the West African sahel SO WATER RESOURCES RESEARCH LA English DT Article ID OPTICAL-THICKNESS; AEROSOL; CLIMATE; SPECTROMETER AB Dust aerosols can suppress rainfall by increasing the number of cloud condensation nuclei in warm clouds and affecting the surface radiation budget and boundary layer instability. The extent to which atmospheric dust may affect precipitation yields and the hydrologic cycle in semiarid regions remains poorly understood. We investigate the relationship between dust aerosols and rainfall in the West African Sahel where the dust-rainfall feedback has been speculated to contribute to sustained droughts. We find that the amount of dust loadings is negatively correlated with rainfall values, suggesting that dust entrained in the atmosphere can significantly inhibit rainfall in this region. C1 [Hui, Wanching Jacquie; Ravi, Sujith; Fuentes, Jose D.; D'Odorico, Paolo] Univ Virginia, Dept Environm Sci, Charlottesville, VA 22903 USA. [Cook, Benjamin I.] NASA, Goddard Inst Space Studies, New York, NY 10025 USA. RP Hui, WJ (reprint author), Univ Virginia, Dept Environm Sci, Box 400123, Charlottesville, VA 22903 USA. EM paolo@virginia.edu RI Ravi, Sujith/C-3586-2008; Cook, Benjamin/H-2265-2012; D'Odorico, Paolo/A-5836-2008 OI Ravi, Sujith/0000-0002-0425-9373; NR 28 TC 25 Z9 26 U1 0 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0043-1397 EI 1944-7973 J9 WATER RESOUR RES JI Water Resour. Res. PD MAY 14 PY 2008 VL 44 IS 5 AR W05202 DI 10.1029/2008WR006885 PG 6 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 303TR UT WOS:000256064300002 ER PT J AU Tchoul, MN Ford, WT Ha, MLP Chavez-Sumarriva, I Grady, BP Lolli, GL Resasco, DE Arepalli, S AF Tchoul, Maxim N. Ford, Warren T. Ha, Mai L. P. Chavez-Sumarriva, Israel Grady, Brian P. Lolli, Giulio Resasco, Daniel E. Arepalli, Sivaram TI Composites of single-walled carbon nanotubes and polystyrene: Preparation and electrical conductivity SO CHEMISTRY OF MATERIALS LA English DT Article ID PERCOLATION-THRESHOLD; MECHANICAL-PROPERTIES; NANOCOMPOSITES; DISPERSION; STABILITY; POLYMERS; CATALYST; ROPES; PMMA AB Composites of single-walled carbon nanotubes (SWNT) and polystyrene have been prepared using three different types of SWNT: HiPco, CoMoCat, and pulsed laser vaporization (PLV). Nanotubes were incorporated into the polystyrene matrix by two methods: (1) evaporation of chloroform solutions of SWNT noncovalently functionalized with poly [(m-phenylenevinylene)-co-(2,5 -dioctoxy-p-phenylenevinylene)] (PmPV) and polystyrene; (2) coagulation in water of DMF solutions containing polystyrene and nitric acid oxidized SWNT. From measurements of the electrical conductivities of the composites over a range of concentration from 0.1 to 6 wt % SWNT, the percolation threshold of conductivity was 0.17 - 0.3% SWNT for the PmPV-coated materials and 0.4 - 0.5% for those made by coagulation. Of the three types of SWNT, composites made with HiPco tubes had the highest conductivity. C1 [Tchoul, Maxim N.; Ford, Warren T.] Oklahoma State Univ, Dept Chem, Stillwater, OK 74078 USA. [Ha, Mai L. P.; Chavez-Sumarriva, Israel; Grady, Brian P.; Lolli, Giulio] Univ Oklahoma, Sch Chem Biol & Mat Engn, Norman, OK 73019 USA. [Arepalli, Sivaram] NASA, Johnson Space Ctr, ERC Inc, Houston, TX 77058 USA. RP Ford, WT (reprint author), Oklahoma State Univ, Dept Chem, 107 Phys Sci I, Stillwater, OK 74078 USA. EM warren.ford@okstate.edu RI Arepalli, Sivaram/A-5372-2010 NR 36 TC 60 Z9 61 U1 6 U2 41 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0897-4756 EI 1520-5002 J9 CHEM MATER JI Chem. Mat. PD MAY 13 PY 2008 VL 20 IS 9 BP 3120 EP 3126 DI 10.1021/cm703625w PG 7 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 297NM UT WOS:000255623400047 ER PT J AU Wilson, GW Austermann, JE Perera, TA Scott, KS Ade, PAR Bock, JJ Glenn, J Golwala, SR Kim, S Kang, Y Lydon, D Mauskopf, PD Predmore, CR Roberts, CM Souccar, K Yun, MS AF Wilson, G. W. Austermann, J. E. Perera, T. A. Scott, K. S. Ade, P. A. R. Bock, J. J. Glenn, J. Golwala, S. R. Kim, S. Kang, Y. Lydon, D. Mauskopf, P. D. Predmore, C. R. Roberts, C. M. Souccar, K. Yun, M. S. TI The AzTEC mm-wavelength camera SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE instrumentation : detectors; galaxies : high redshift; galaxies : starburst; submillimetre ID BOLOMETER ARRAY; BOLOCAM; OPTIMIZATION; TELESCOPE AB AzTEC is a mm-wavelength bolometric camera utilizing 144 silicon nitride micromesh detectors. Here, we describe the AzTEC instrument architecture and its use as an astronomical instrument. We report on several performance metrics measured during a three-month observing campaign at the James Clerk Maxwell Telescope and conclude with our plans for AzTEC as a facility instrument on the Large Millimetre Telescope. C1 [Wilson, G. W.; Austermann, J. E.; Perera, T. A.; Lydon, D.; Roberts, C. M.; Souccar, K.; Yun, M. S.] Univ Massachusetts, Dept Astron, Amherst, MA 01003 USA. [Ade, P. A. R.; Mauskopf, P. D.] Cardiff Univ, Cardiff CF24 3YB, Wales. [Bock, J. J.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Glenn, J.] Univ Colorado, Ctr Astrophys & Space Astron, Boulder, CO 80309 USA. [Golwala, S. R.] CALTECH, Pasadena, CA 91125 USA. [Kim, S.; Kang, Y.] Sejong Univ, Dept Astron & Space Sci, Seoul 143747, South Korea. [Predmore, C. R.] Predmore Assoc, S Deerfield, MA 01373 USA. RP Wilson, GW (reprint author), Univ Massachusetts, Dept Astron, Amherst, MA 01003 USA. EM wilson@astro.umass.edu NR 18 TC 119 Z9 119 U1 1 U2 3 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD MAY 11 PY 2008 VL 386 IS 2 BP 807 EP 818 DI 10.1111/j.1365-2966.2008.12980.x PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 292ST UT WOS:000255287100015 ER PT J AU Engelbracht, CW Rieke, GH Gordon, KD Smith, JDT Werner, MW Moustakas, J Willmer, CNA Vanzi, L AF Engelbracht, C. W. Rieke, G. H. Gordon, K. D. Smith, J. -D. T. Werner, M. W. Moustakas, J. Willmer, C. N. A. Vanzi, L. TI Metallicity effects on dust properties in starbursting galaxies SO ASTROPHYSICAL JOURNAL LA English DT Review DE galaxies : ISM; infrared : galaxies ID COMPACT DWARF GALAXIES; MULTIBAND IMAGING PHOTOMETER; LUMINOUS INFRARED GALAXIES; SPITZER-SPACE-TELESCOPE; DIGITAL SKY SURVEY; SPECTRAL ENERGY-DISTRIBUTION; PRIMORDIAL HELIUM ABUNDANCE; EMISSION-LINE GALAXIES; MASSIVE STAR-FORMATION; WOLF-RAYET GALAXIES AB We present infrared observations of 66 starburst galaxies over the full range of oxygen abundances observed in local star-forming galaxies, from 12 + log(O/H) = 7.1 to 8.9. The data include imaging and spectroscopy from the Spitzer Space Telescope, supplemented by ground-based near-infrared imaging. We confirm a strong correlation of aromatic emission with metallicity, with a threshold at 12 + log(O/H) similar to 8. We show that the far-infrared color temperature of the large dust grains increases toward lower metallicity, peaking at a metallicity of 8 before turning over. We compute dust masses and compare them to H I masses from the literature to derive the ratio of atomic gas to dust, which increases by nearly 3 orders of magnitude between solar metallicity and a metallicity of 8, below which it flattens out. The abrupt change in aromatic emission at mid-infrared wavelengths thus appears to be reflected in the far-infrared properties, indicating that metallicity changes affect the composition of the full range of dust grain sizes that dominate the infrared emission. Although the great majority of galaxies show similar patterns of behavior as described above, there are three exceptions, SBS 0335-052E, Haro 11, and SHOC 391. Their infrared SEDs are dominated energetically by the mid-IR near 24 mu m rather than by the 60-200 mu m region. In addition, they have very weak near-infrared outputs and their SEDs are dominated by emission by dust at wavelengths as short as 1.8 mu m. The latter behavior indicates that the dominant star-forming episodes in them are extremely young. The component of the ISM responsible for the usual far-infrared emission appears to be either missing or inefficiently heated in these three galaxies. C1 [Engelbracht, C. W.; Rieke, G. H.; Gordon, K. D.; Smith, J. -D. T.; Willmer, C. N. A.] Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. [Werner, M. W.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Moustakas, J.] NYU, Dept Phys, New York, NY 10003 USA. [Vanzi, L.] European So Observ, Santiago 19, Chile. [Vanzi, L.] Pontificia Univ Catolica Chile, Dept Elect Engn, Santiago, Chile. RP Engelbracht, CW (reprint author), Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. RI Vanzi, Leonardo/D-1381-2014 NR 149 TC 176 Z9 176 U1 0 U2 7 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD MAY 10 PY 2008 VL 678 IS 2 BP 804 EP 827 DI 10.1086/529513 PG 24 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 294XE UT WOS:000255438800024 ER PT J AU Boogert, ACA Pontoppidan, KM Knez, C Lahuis, F Kessler-Silacci, J van Dishoeck, EF Blake, GA Augereau, JC Bisschop, SE Bottinelli, S Brooke, TY Brown, J Crapsi, A Evans, NJ Fraser, HJ Geers, V Huard, TL Jorgensen, JK Oberg, KI Allen, LE Harvey, PM Koerner, DW Mundy, LG Padgett, DL Sargent, AI Stapelfeldt, KR AF Boogert, A. C. A. Pontoppidan, K. M. Knez, C. Lahuis, F. Kessler-Silacci, J. van Dishoeck, E. F. Blake, G. A. Augereau, J. -C. Bisschop, S. E. Bottinelli, S. Brooke, T. Y. Brown, J. Crapsi, A. Evans, N. J., II Fraser, H. J. Geers, V. Huard, T. L. Jorgensen, J. K. Oberg, K. I. Allen, L. E. Harvey, P. M. Koerner, D. W. Mundy, L. G. Padgett, D. L. Sargent, A. I. Stapelfeldt, K. R. TI The c2d Spitzer spectroscopic survey of ices around low-mass young stellar objects. I. H2O and the 5-8 mu m bands SO ASTROPHYSICAL JOURNAL LA English DT Article DE astrochemistry; infrared : ISM; infrared : stars; ISM : abundances; ISM : molecules; stars : formation ID INFRARED SPECTROGRAPH IRS; ISO-SWS OBSERVATIONS; MU-M SPECTRUM; INTERSTELLAR ICE; SPACE-TELESCOPE; EMBEDDED PROTOSTARS; ABSORPTION FEATURES; SOLID METHANOL; MICRON SPECTRA; GRAIN MANTLES AB To study the physical and chemical evolution of ices in solar-mass systems, a spectral survey is conducted of a sample of 41 low-luminosity YSOs (L similar to 0.1-10 L-circle dot) using 3-38 mu m Spitzer and ground-based spectra. The sample is complemented with previously published Spitzer spectra of background stars and with ISO spectra of well-studied massive YSOs (L similar to 10(5) L-circle dot). The long-known 6.0 and 6.85 mu m bands are detected toward all sources, with the Class 0-type YSOs showing the deepest bands ever observed. The 6.0 mu m band is often deeper than expected from the bending mode of pure solid H2O. The additional 5-7 mu m absorption consists of five independent components, which, by comparison to laboratory studies, must be from at least eight different carriers. Much of this absorption is due to simple species likely formed by grain surface chemistry, at abundances of 1%-30% for CH3OH, 3%-8% for NH3, 1%-5% for HCOOH, similar to 6% for H2CO, and similar to 0.3% for HCOO- relative to solid H2O. The 6.85 mu m band has one or two carriers, of which one may be less volatile than H2O. Its carrier(s) formed early in the molecular cloud evolution and do not survive in the diffuse ISM. If an NH4+- containing salt is the carrier, its abundance relative to solid H2O is similar to 7%, demonstrating the efficiency of low-temperature acid-base chemistry or cosmic-ray-induced reactions. Possible origins are discussed for enigmatic, very broad absorption between 5 and 8 mu m. Finally, the same ices are observed toward massive and low-mass YSOs, indicating that processing by internal UV radiation fields is a minor factor in their early chemical evolution. C1 [Boogert, A. C. A.; Brown, J.; Sargent, A. I.] CALTECH, Div PMA, Pasadena, CA 91125 USA. [Boogert, A. C. A.] Gemini Sci Ctr, AURA NOAO S, La Serena, Chile. [Pontoppidan, K. M.; Blake, G. A.] CALTECH, Div GPS, Pasadena, CA 91125 USA. [Knez, C.; Mundy, L. G.] Univ Maryland, Dept Astron, College Pk, MD 20742 USA. [Lahuis, F.; van Dishoeck, E. F.; Bisschop, S. E.; Bottinelli, S.; Crapsi, A.; Geers, V.; Oberg, K. I.] Leiden Univ, Leiden Observ, NL-2300 RA Leiden, Netherlands. [Lahuis, F.] Univ Groningen, SRON, NL-9700 AV Groningen, Netherlands. [Kessler-Silacci, J.; Evans, N. J., II; Harvey, P. M.] Univ Texas Austin, Dept Astron, Austin, TX 78712 USA. [Augereau, J. -C.] Univ Grenoble 1, CNRS, Lab Astrophys Grenoble, UMR 5571, Grenoble, France. [Brooke, T. Y.; Padgett, D. L.] CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA. [Fraser, H. J.] Univ Strathclyde, Scottish Univ Phys Alliance, Dept Phys, Glasgow G4 ONG, Lanark, Scotland. [Huard, T. L.; Jorgensen, J. K.; Allen, L. E.] Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. [Koerner, D. W.] No Arizona Univ, Dept Phys & Astron, Flagstaff, AZ 86011 USA. [Stapelfeldt, K. R.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Boogert, ACA (reprint author), CALTECH, NASA Herschel Sci Ctr, IPAC, Pasadena, CA 91125 USA. EM aboogert@ipac.caltech.edu RI Stapelfeldt, Karl/D-2721-2012; Jorgensen, Jes Kristian/L-7936-2014 OI Jorgensen, Jes Kristian/0000-0001-9133-8047 NR 82 TC 203 Z9 203 U1 1 U2 14 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 10 PY 2008 VL 678 IS 2 BP 985 EP 1004 DI 10.1086/533425 PG 20 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 294XE UT WOS:000255438800036 ER PT J AU Sitko, ML Carpenter, WJ Kimes, RL Wilde, JL Lynch, DK Russell, RW Rudy, RJ Mazuk, SM Venturini, CC Puetter, RC Grady, CA Polomski, EF Wisnewski, JP Brafford, SM Hammel, HB Perry, RB AF Sitko, Michael L. Carpenter, William J. Kimes, Robin L. Wilde, J. Leon Lynch, David K. Russell, Ray W. Rudy, Richard J. Mazuk, Stephan M. Venturini, Catherine C. Puetter, Richard C. Grady, Carol A. Polomski, Elisha F. Wisnewski, John P. Brafford, Suellen M. Hammel, H. B. Perry, R. Brad TI Variability of disk emission in pre-main-sequence and related stars. I. HD 31648 and HD 163296: Isolated Herbig Ae stars driving Herbig-Haro flows SO ASTROPHYSICAL JOURNAL LA English DT Article DE circumstellar matter; infrared : stars; planetary systems : protoplanetary disks stars : formation; stars : individual (HD 31648, HD 163296); stars : pre-main-sequence ID 2-DIMENSIONAL RADIATIVE-TRANSFER; T-TAURI STARS; SPECTRAL IRRADIANCE CALIBRATION; WEAKLY MAGNETIZED DISKS; LOCAL SHEAR INSTABILITY; YOUNG STELLAR OBJECTS; AE/BE STARS; CIRCUMSTELLAR DUST; PROTOSTELLAR ENVELOPES; PROTOPLANETARY DISKS AB Infrared photometry and spectroscopy covering a time span of a quarter-century are presented for HD 31648 (MWC 480) and HD 163296 (MWC 275). Both are isolated Herbig Ae stars that exhibit signs of active accretion, including driving bipolar flows with embedded Herbig-Haro (HH) objects. HD 163296 was found to be relatively quiescent photometrically in its inner disk region, with the exception of a major increase in emitted flux in a broad wavelength region centered near 3 mu m in 2002. In contrast, HD 31648 has exhibited sporadic changes in the entire 3 13 mu m region throughout this span of time. In both stars, the changes in the 1-5 mu m flux indicate structural changes in the region of the disk near the dust sublimation zone, possibly causing its distance from the star to vary with time. Repeated thermal cycling through this region will result in the preferential survival of large grains, and an increase in the degree of crystallinity. The variability observed in these objects has important consequences for the interpretation of other types of observations. For example, source variability will compromise models based on interferometry measurements unless the interferometry observations are accompanied by nearly simultaneous photometric data. C1 [Sitko, Michael L.; Carpenter, William J.; Kimes, Robin L.; Wilde, J. Leon] Univ Cincinnati, Dept Phys, Cincinnati, OH 45221 USA. [Sitko, Michael L.; Hammel, H. B.] Space Sci Inst, Boulder, CO 80301 USA. [Lynch, David K.; Russell, Ray W.; Rudy, Richard J.; Mazuk, Stephan M.; Venturini, Catherine C.] Aerosp Corp, Los Angeles, CA 90009 USA. [Puetter, Richard C.] Univ Calif San Diego, Ctr Astrophys & Space Sci, La Jolla, CA 92093 USA. [Grady, Carol A.; Wisnewski, John P.] NASA, Goddard Space Flight Ctr, Exoplanets & Stellar Astrophys Lab, Greenbelt, MD 20771 USA. [Grady, Carol A.] Eureka Sci Inc, Oakland, CA 94602 USA. [Polomski, Elisha F.] Univ Minnesota, Dept Astron, Minneapolis, MN 55455 USA. [Perry, R. Brad] NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Sitko, ML (reprint author), Univ Cincinnati, Dept Phys, Cincinnati, OH 45221 USA. EM michael.sitko@uc.edu; carpenwj@physics.uc.edu; kimesrl@email.uc.edu; jlwilde@bgnet.bgsu.edu; David.K.Lynch@aero.org; Ray.W.Russell@aero.org; Richard.J.Rudy@aero.org; Stephan.M.Mazuk@aero.org; Catherine.C.Venturini@aero.org; rpuetter@ucsd.edu; cgrady@milkyway.gsfc.nasa.gov; Elisha.Polomski@uwsp.edu; jwisnie@miklyway.gsfc.nasa.gov; SMBlawyer@fuse.net; hbh@alum.mit.edu; Perry@NASA.gov NR 90 TC 51 Z9 51 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 10 PY 2008 VL 678 IS 2 BP 1070 EP 1087 DI 10.1086/529003 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 294XE UT WOS:000255438800041 ER PT J AU Kasliwal, MM Cenko, SB Kulkarni, SR Cameron, PB Nakar, E Ofek, EO Rau, A Soderberg, AM Campana, S Bloom, JS Perley, DA Pollack, LK Barthelmy, S Cummings, J Gehrels, N Krimm, HA Markwardt, CB Sato, G Chandra, P Frail, D Fox, DB Price, PA Berger, E Grebenev, SA Krivonos, RA Sunyaev, RA AF Kasliwal, M. M. Cenko, S. B. Kulkarni, S. R. Cameron, P. B. Nakar, E. Ofek, E. O. Rau, A. Soderberg, A. M. Campana, S. Bloom, J. S. Perley, D. A. Pollack, L. K. Barthelmy, S. Cummings, J. Gehrels, N. Krimm, H. A. Markwardt, C. B. Sato, G. Chandra, P. Frail, D. Fox, D. B. Price, P. A. Berger, E. Grebenev, S. A. Krivonos, R. A. Sunyaev, R. A. TI GRB 070610: A curious galactic transient SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; stars : flare; X-rays : binaries; X-rays : bursts; X-rays : individual (Swift J195509.6+261406) ID GAMMA-RAY BURSTS; ALL-SKY SURVEY; V4641 SAGITTARII; LIGHT CURVES; BLACK-HOLE; GRO J1744-28; CYGNUS X-1; SWIFT; TELESCOPE; OUTBURST AB GRB 070610 is a typical high-energy event with a duration of 5 s. Yet within the burst localization we detect a highly unusual X-ray and optical transient, Swift J195509.6+261406. We see high-amplitude X-ray and optical variability on very short timescales even at late times. Using near-infrared imaging assisted by a laser guide star and adaptive optics, we identified the counterpart of Swift J195509.6+261406. Late-time optical and near-infrared imaging constrain the spectral type of the counterpart to be fainter than a K-dwarf, assuming it is of Galactic origin. It is possible that GRB 070610 and Swift J195509.6+261406 are unrelated sources. However, the absence of a typical X-ray afterglow from GRB 070610 in conjunction with the spatial and temporal coincidence of the two motivate us to suggest that the sources are related. The closest (imperfect) analog to Swift J195509.6+261406 is V4641 Sgr, an unusual black hole binary. We suggest that Swift J195509.6+261406 along with V4641 Sgr define a subclass of stellar black hole binaries-the fast X-ray novae. We further suggest that fast X-ray novae are associated with bursts of gamma rays. If so, GRB 070610 defines a new class of celestial gamma-ray bursts and these bursts dominate the long-duration GRB demographics. C1 [Kasliwal, M. M.; Kulkarni, S. R.; Cameron, P. B.; Nakar, E.; Ofek, E. O.; Rau, A.; Soderberg, A. M.] CALTECH, Div Phys Math & Astron, Pasadena, CA 91125 USA. [Cenko, S. B.] CALTECH, Space Radiat Lab, Pasadena, CA 91125 USA. [Campana, S.] Osservatorio Astron Breva, I-23807 Merate, LC, Italy. [Bloom, J. S.; Perley, D. A.] Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. [Pollack, L. K.] Univ Calif Santa Cruz, Dept Astron & Astrophys, Santa Cruz, CA 95064 USA. [Barthelmy, S.; Cummings, J.; Gehrels, N.; Sato, G.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Krimm, H. A.; Markwardt, C. B.] NASA, Goddard Space Flight Ctr, Astroparticle Phys Lab, Greenbelt, MD 20771 USA. [Krimm, H. A.; Markwardt, C. B.] CRESST, Greenbelt, MD 20771 USA. [Krimm, H. A.] Univ Space Res Assoc, Columbia, MD 21044 USA. [Markwardt, C. B.] Univ Maryland, Dept Astron, College Pk, MD 20742 USA. [Chandra, P.] Univ Virginia, Charlottesville, VA 22903 USA. [Frail, D.] Natl Radio Astron Observ, Socorro, NM 87801 USA. [Fox, D. B.] Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. [Price, P. A.] Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA. [Berger, E.] Observ Carnegie Inst Washington, Pasadena, CA 91101 USA. [Berger, E.] Princeton Univ Observ, Princeton, NJ 08544 USA. [Grebenev, S. A.; Krivonos, R. A.; Sunyaev, R. A.] Space Res Inst, Moscow 117997, Russia. [Krivonos, R. A.] Max Planck Inst Astrophys, D-85741 Garching, Germany. RP Kasliwal, MM (reprint author), CALTECH, Div Phys Math & Astron, MS 105-24, Pasadena, CA 91125 USA. RI Barthelmy, Scott/D-2943-2012; Gehrels, Neil/D-2971-2012 NR 71 TC 25 Z9 25 U1 0 U2 6 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD MAY 10 PY 2008 VL 678 IS 2 BP 1127 EP 1135 DI 10.1086/526407 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 294XE UT WOS:000255438800046 ER PT J AU Titarchuk, L Shaposhnikov, N AF Titarchuk, Lev Shaposhnikov, Nikolai TI On the nature of the variability power decay toward soft spectral states in X-ray binaries: Case study in Cygnus X-1 SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; black hole physics; radiation mechanisms : nonthermal; stars : individual (Cygnus X-1) ID QUASI-PERIODIC OSCILLATIONS; BLACK-HOLE BINARIES; NEUTRON-STAR; FREQUENCY CORRELATION; X-1; INDEX; MASS; PROPAGATION; NOISE AB A characteristic feature of the Fourier power density spectrum (PDS) observed from black hole X-ray binaries in low/hard and intermediate spectral states is a broadband-limited noise characterized by a constant below some frequency (a "break'' frequency) and a power law above this frequency. It has been shown that the variability of this type can be produced by the inward diffusion of the local driving perturbations in a bounded configuration (accretion disk or corona). In the framework of this model, the perturbation diffusion time t(0) is related to the phenomenological break frequency, while the PDS power-law slope above the "break'' is determined by the viscosity distribution over the configuration. The perturbation diffusion scenario explains the decay of the power of X-ray variability observed in a number of compact sources (containing black holes and neutron stars) during an evolution of these sources from low/hard to high/soft states. We compare the model predictions with the subset of data from Cyg X-1 collected by the Rossi X-Ray Time Explorer (RXTE). Our extensive analysis of the Cyg X-1 PDSs demonstrates that the observed integrated power P(x) decreases approximately as the square root of the characteristic frequency of the driving oscillations V(dr). The RXTE observations of Cyg X-1 allow us to infer P(dr) and t(0) as a function of V(dr). Using the inferred dependences of the integrated power of the driving oscillations P(dr) and t(0) on V(dr) we demonstrate that the power predicted by the model also decays as P(x,diff) alpha V(dr)(-0.5), which is similar to the observed Px behavior. We also apply the basic parameters of observed PDSs, power-law indices, and low-frequency quasi-periodic oscillations to infer the Reynolds number (Re) from the observations using the method developed in our previous paper. Our analysis shows that Re increases from values of about 10 in low/hard state to about 70 during the high/soft state. C1 [Titarchuk, Lev] George Mason Univ, Ctr Earth Observing & Space Res, Fairfax, VA 22030 USA. [Titarchuk, Lev] USN, Res Lab, Washington, DC 20375 USA. [Titarchuk, Lev] Univ Ferrara, Dipartmento Fis, I-44100 Ferrara, Italy. [Shaposhnikov, Nikolai] NASA, Goddard Space Flight Ctr, Univ Space Res Assoc, Greenbelt, MD 20771 USA. RP Titarchuk, L (reprint author), George Mason Univ, Ctr Earth Observing & Space Res, Fairfax, VA 22030 USA. EM ltitarchuk@ssd5.nrl.navy.mil; nikolai@milkyway.gsfc.nasa.gov NR 24 TC 8 Z9 8 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 10 PY 2008 VL 678 IS 2 BP 1230 EP 1236 DI 10.1086/587124 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 294XE UT WOS:000255438800055 ER PT J AU Cushing, MC Marley, MS Saumon, D Kelly, BC Vacca, WD Rayner, JT Freedman, RS Lodders, K Roellig, TL AF Cushing, Michael C. Marley, Mark S. Saumon, D. Kelly, Brandon C. Vacca, William D. Rayner, John T. Freedman, Richard S. Lodders, Katharina Roellig, Thomas L. TI Atmospheric parameters of field L and T dwarfs SO ASTROPHYSICAL JOURNAL LA English DT Article DE infrared : stars; radiative transfer; stars : fundamental parameters; stars : low-mass; brown dwarfs ID ALL-SKY SURVEY; EXTRASOLAR GIANT PLANETS; SPITZER-SPACE-TELESCOPE; NEAR-INFRARED SPECTRA; STAR ADAPTIVE OPTICS; DIRTY DUST GRAINS; BROWN DWARFS; ULTRACOOL DWARFS; L/T TRANSITION; MODEL ATMOSPHERES AB We present an analysis of the 0.95-14.5 mu m spectral energy distributions of nine field ultracool dwarfs with spectral types ranging from L1 to T4.5. Effective temperatures, gravities, and condensate cloud sedimentation efficiencies are derived by comparing the data to synthetic spectra computed from atmospheric models that self-consistently include the formation of condensate clouds. Overall, the model spectra fit the data well, although the agreement at some wavelengths remains poor due to remaining inadequacies in the models. Derived effective temperatures decrease steadily through the L1-T4.5 spectral types, and we confirm that the effective temperatures of ultracool dwarfs at the L/T transition are nearly constant, decreasing by only similar to 200 K from spectral types L7.5 to T4.5. The condensate cloud properties vary significantly among the L dwarfs in our sample, ranging from very thick clouds to relatively thin clouds with no particular trend with spectral type. The two objects in our sample with very red J - K(s) colors are, however, best fitted with synthetic spectra that have thick clouds, which hints at a possible correlation between the near-infrared colors of L dwarfs and the condensate cloud properties. The fits to the two T dwarfs in our sample (T2 and T4.5) also suggest that the clouds become thinner in this spectral class, in agreement with previous studies. Restricting the fits to narrower wavelength ranges (i.e., individual photometric bands) almost always yields excellent agreement between the data and models. Limitations in our knowledge of the opacities of key absorbers such as FeH, VO, and CH(4) at certain wavelengths remain obvious, however. The effective temperatures obtained by fitting the narrower wavelength ranges can show a large scatter compared to the values derived by fitting the full spectral energy distributions; deviations are typically similar to 200 K and, in the worst cases, up to 700 K. C1 [Cushing, Michael C.; Rayner, John T.] Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA. [Cushing, Michael C.; Kelly, Brandon C.] Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. [Saumon, D.] Los Alamos Natl Lab, Div Appl Phys, Los Alamos, NM 87545 USA. [Vacca, William D.] NASA, Ames Res Ctr, SOFIA USRA, Moffett Field, CA 94035 USA. [Freedman, Richard S.] NASA, Ames Res Ctr, SETI Inst, Moffett Field, CA 94035 USA. [Lodders, Katharina] Washington Univ, Dept Earth & Planetary Sci, Planetary Chem Lab, St Louis, MO 63130 USA. RP Cushing, MC (reprint author), Univ Hawaii, Inst Astron, 2680 Woodlawn Dr, Honolulu, HI 96822 USA. EM mcushing@ifa.hawaii.edu; mark.s.marley@nasa.gov; dsaumon@lanl.gov; bkelly@as.arizona.edu; wvacca@mail.arc.nasa.gov; rayner@ifa.hawaii.edu; freedman@darkstar.arc.nasa.gov; lodders@levee.wustl.edu; thomas.l.roellig@nasa.gov RI Marley, Mark/I-4704-2013 NR 100 TC 156 Z9 156 U1 1 U2 7 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 10 PY 2008 VL 678 IS 2 BP 1372 EP 1395 DI 10.1086/526489 PG 24 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 294XE UT WOS:000255438800069 ER PT J AU Fortney, JJ Lodders, K Marley, MS Freedman, RS AF Fortney, J. J. Lodders, K. Marley, M. S. Freedman, R. S. TI A unified theory for the atmospheres of the hot and very hot jupiters: Two classes of irradiated atmospheres SO ASTROPHYSICAL JOURNAL LA English DT Review DE planetary systems; radiative transfer ID EXTRASOLAR GIANT PLANETS; MASS DWARF STARS; SPECTRAL TYPE-L; HD 209458B; BROWN DWARFS; LIGHT CURVES; SECONDARY ECLIPSE; TRANSITING PLANET; THERMAL EMISSION; CHEMICAL-EQUILIBRIUM AB We highlight the importance of gaseous TiO and VO opacity on the highly irradiated close-in giant planets. The day-side atmospheres of these planets naturally fall into two classes that are somewhat analogous to the M- and L-type dwarfs. Those that are warm enough to have appreciable opacity due to TiO and VO gases we term "pM class'' planets, and those that are cooler we term "pL class'' planets. We calculate model atmospheres for these planets, including pressure-temperature profiles, spectra, and characteristic radiative time constants. We show that pM class planets have temperature inversions (hot stratospheres), appear "anomalously'' bright in the mid-infrared secondary eclipse, and feature molecular bands in emission rather than absorption. From simple physical arguments, we show that they will have large day/night temperature contrasts and negligible phase shifts between orbital phase and thermal emission light curves, because radiative timescales are much shorter than possible dynamical timescales. The pL class planets absorb incident flux deeper in the atmosphere where atmospheric dynamics will more readily redistribute absorbed energy. This will lead to cooler day sides, warmer night sides, and larger phase shifts in thermal emission light curves. The boundary between these classes (similar to 0.04-0.05 AU from a Sun-like primary for solar composition) is particularly dependent on the incident flux from the parent star, and less so on other factors. We apply these results to several planets and note that the eccentric transiting planets HD 147506b and HD 17156b alternate between the classes. Thermal emission in the optical from pM class planets is significant redward of 400 nm, making these planets attractive targets for optical detection. The difference in the observed day/night contrast between v And b (pM class) and HD 189733b (pL class) is naturally explained in this scenario. C1 [Fortney, J. J.; Marley, M. S.; Freedman, R. S.] NASA, Ames Res Ctr, Space Sci & Astrobiol Div, Moffett Field, CA 94035 USA. [Lodders, K.] Washington Univ, Dept Earth & Planetary Sci, Planetary Chem Lab, St Louis, MO 63130 USA. RP Fortney, JJ (reprint author), SETI Inst, Carl Sagan Ctr, 515 N Whisman Rd, Mountain View, CA 94043 USA. EM jfortney@ucolick.org RI Marley, Mark/I-4704-2013; OI Fortney, Jonathan/0000-0002-9843-4354 NR 103 TC 349 Z9 350 U1 6 U2 25 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 10 PY 2008 VL 678 IS 2 BP 1419 EP 1435 DI 10.1086/528370 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 294XE UT WOS:000255438800072 ER PT J AU Tan, LC Reames, DV Ng, CK AF Tan, Lun C. Reames, Donald V. Ng, Chee K. TI Ion anisotropy and high-energy variability of large solar particle events: A comparative study SO ASTROPHYSICAL JOURNAL LA English DT Article DE acceleration of particles; interplanetary medium; shock waves; Sun : coronal mass ejections (CMEs); Sun : particle emission ID HYDROMAGNETIC WAVE EXCITATION; CORONAL MASS EJECTION; INTERPLANETARY SHOCKS; HEAVY-IONS; ANGULAR-DISTRIBUTIONS; WIND SPACECRAFT; ALFVEN WAVES; 1 AU; TRANSPORT; ACCELERATION AB We have made comparative studies of ion anisotropy and high-energy variability of solar energetic particle (SEP) events previously examined by the Solar, Heliospheric, and Interplanetary Environment (SHINE) Workshop campaign. We have found distinctly different characteristics of SEPs in two large "gradual'' events having very similar solar progenitors (the 2002 April 21 and August 24 events). Since the scattering centers of SEPs are approximately frozen in the solar wind, we emphasize work in the solar-wind frame, where SEPs tend to be isotropized and small anisotropies are easier to detect. While in the August event no streaming reversal occurred, in the April event the field-aligned anisotropy of all heavy ions showed signs of streaming reversal. The difference in streaming reversal was consistent with the difference in the presence of the outer reflecting boundary. In the April event the magnetic mirror, which was located behind the interplanetary shock driven by the preceding coronal mass ejection (CME), could block the stream of SEPs, while in the August event SEPs escaped freely in the absence of any nearby boundary. The magnetic mirror was formed at the bottleneck of magnetic field lines draped around a flank of the preceding CME. In previous SHINE event analysis, the contrasting event durations and Fe/O ratios of the both events were explained as the interplay between shock geometry and seed population. Our new findings, however, indicate that event duration and time, as well as spectral variation, are also affected by the presence of a nearby reflecting boundary. C1 [Tan, Lun C.; Reames, Donald V.; Ng, Chee K.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Tan, LC (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM ltan@mail630.gsfc.nasa.gov NR 28 TC 11 Z9 11 U1 1 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 10 PY 2008 VL 678 IS 2 BP 1471 EP 1479 DI 10.1086/533490 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 294XE UT WOS:000255438800075 ER PT J AU Blake, CH Charbonneau, D White, RJ Torres, G Marley, MS Saumon, D AF Blake, Cullen H. Charbonneau, David White, Russel J. Torres, Guillermo Marley, Mark S. Saumon, Didier TI A spectroscopic binary at the M/L transition SO ASTROPHYSICAL JOURNAL LETTERS LA English DT Article DE stars : low-mass; brown dwarfs; techniques : radial velocities ID LOW-MASS STARS; BROWN DWARFS; ULTRACOOL DWARFS; VELOCITIES; ALGORITHM; DISCOVERY; ELEMENTS; PLANETS; CLOUDS; SYSTEM AB We report the discovery of a single-lined spectroscopic binary with an ultracool dwarf (UCD) primary with a spectral type between M8 and L0.5. This system was discovered during the course of an ongoing survey to monitor L dwarfs for radial velocity variations and is the first known small-separation (a < 1 AU) spectroscopic binary among dwarfs at the M/L transition. Based on radial velocity measurements with a typical precision of 300 m s(-1), we estimate the orbital parameters of this system to be P = 246.73 +/- 0.49 days, a(1) sin i = 0.159 +/- 0.003 AU, and M-2 sin i = 0.2062(M-1 + M-2)(2/3) +/- 0.0034 M-circle dot. Assuming a primary mass of M-1 = 0.08M(circle dot) (based on spectral type), we estimate the secondary minimum mass to be M-2 sin i = 0.054 M-circle dot. With future photometric, spectroscopic, and interferometric observations it may be possible to determine the dynamical masses of both components directly, making this system one of the best-characterized UCD binaries known. C1 [Blake, Cullen H.; Charbonneau, David; Torres, Guillermo] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. [White, Russel J.] Univ Alabama, Dept Phys, Huntsville, AL 35899 USA. [Marley, Mark S.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. [Saumon, Didier] Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Blake, CH (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM cblake@cfa.harvard.edu RI Marley, Mark/I-4704-2013; OI Charbonneau, David/0000-0002-9003-484X NR 33 TC 31 Z9 31 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA J9 ASTROPHYS J LETT JI Astrophys. J. Lett. PD MAY 10 PY 2008 VL 678 IS 2 BP L125 EP L128 DI 10.1086/588754 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 292AP UT WOS:000255239100013 ER PT J AU Woo, R Druckmullerova, H AF Woo, Richard Druckmullerova, Hana TI Solar eclipse images and the solar wind SO ASTROPHYSICAL JOURNAL LETTERS LA English DT Article DE Sun : corona ID POLAR CORONAL HOLE; MAGNETIC-FIELDS; FILAMENTARY STRUCTURES; STREAMERS; ULYSSES; ORIGIN; SUN; EVOLUTION; MINIMUM; SLOW AB Over the past decade, diverse observations of the Sun, corona, and heliosphere during solar minimum have repeatedly shown that the solar wind expands radially from the entire Sun. These results are, however, at odds with the conventional view of superradial expansion from polar coronal holes. The purpose of this Letter is to reconcile this conflict by taking a closer look at solar eclipse pictures on which the conventional view is based. The latter are referred to as processed solar eclipse pictures because they are obtained with a radially graded density filter or by the merging of images taken at different exposures and subsequent numerical image processing. We illustrate the importance of quantitative studies in understanding imaging by comparing numerically processed images and isophotes from the 2006 solar eclipse. Familiar large-scale structures traditionally interpreted in terms of density as diverging polar coronal holes and converging coronal streamers are in fact features of differenced density. This mistaking of differenced density for density when interpreting processed pictures misguided our notions of solar wind expansion, and hindered progress in connecting observations between the Sun and solar wind for three decades. C1 [Woo, Richard] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Druckmullerova, Hana] Brno Univ Technol, Fac Mech Engn, Inst Math, CZ-61669 Brno, Czech Republic. RP Woo, R (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,MS 238-725, Pasadena, CA 91109 USA. EM richard.woo@jpl.nasa.gov; hanadruck@seznam.cz NR 43 TC 5 Z9 5 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA J9 ASTROPHYS J LETT JI Astrophys. J. Lett. PD MAY 10 PY 2008 VL 678 IS 2 BP L149 EP L152 DI 10.1086/588729 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 292AP UT WOS:000255239100019 ER PT J AU Huang, XL Yang, WZ Loeb, NG Ramaswamy, V AF Huang, Xianglei Yang, Wenze Loeb, Norman G. Ramaswamy, V. TI Spectrally resolved fluxes derived from collocated AIRS and CERES measurements and their application in model evaluation: Clear sky over the tropical oceans SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID EARTH RADIATION BUDGET; ENERGY SYSTEM INSTRUMENT; ATMOSPHERIC INFRARED SOUNDER; OUTGOING LONGWAVE RADIATION; ANGULAR-DISTRIBUTION MODELS; MOLECULAR SPECTROSCOPIC DATABASE; COOLING RATES; WATER-VAPOR; TERRA SATELLITE; CLIMATE MODELS AB Spectrally resolved outgoing thermal-IR flux, the integrand of the outgoing longwave radiation (OLR), has a unique value in evaluating model simulations. Here we describe an algorithm for deriving such clear-sky outgoing spectral flux through the entire thermal-IR spectrum from the collocated Atmospheric Infrared Sounder (AIRS) and the Clouds and the Earth's Radiant Energy System (CERES) measurements over the tropical oceans. On the basis of the predefined scene types in the CERES Single Satellite Footprint (SSF) data set, spectrally dependent ADMs are developed and used to estimate the spectral flux each AIRS channel. A multivariate linear prediction scheme is then used to estimate spectral fluxes at frequencies not covered by the AIRS instrument. The whole algorithm is validated using synthetic spectra as well as the CERES OLR measurements. Using the GFDL AM2 model simulation as a case study, applications of the derived clear-sky outgoing spectral fluxes in model evaluation are illustrated. By comparing the observed spectral fluxes and simulated ones for the year of 2004, compensating errors in the simulated OLR from different absorption bands are revealed, along with the errors from frequencies within a given absorption band. Discrepancies between the simulated and observed spatial distributions and seasonal evolutions of the spectral fluxes are further discussed. The methodology described in this study can be applied to other surface types as well as cloudy-sky observations and also to corresponding model evaluations. C1 [Huang, Xianglei; Yang, Wenze] Univ Michigan, Dept Atmospher Ocean & Space Sci, Ann Arbor, MI 48109 USA. [Loeb, Norman G.] NASA, Langley Res Ctr, Radiat & Climate Branch, Hampton, VA 23681 USA. [Ramaswamy, V.] Princeton Univ, NOAA, Geophys Fluid Dynam Lab, Princeton, NJ 08542 USA. RP Huang, XL (reprint author), Univ Michigan, Dept Atmospher Ocean & Space Sci, 2455 Hayward St, Ann Arbor, MI 48109 USA. RI Huang, Xianglei/G-6127-2011; Yang, Wenze/B-8356-2012 OI Huang, Xianglei/0000-0002-7129-614X; Yang, Wenze/0000-0001-8514-2742 NR 59 TC 18 Z9 18 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 10 PY 2008 VL 113 IS D9 AR D09110 DI 10.1029/2007JD009219 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 300MH UT WOS:000255827400002 ER PT J AU Migliorini, S Brugge, R O'Neill, A Dobber, M Fioletov, V Levelt, P McPeters, R AF Migliorini, S. Brugge, R. O'Neill, A. Dobber, M. Fioletov, V. Levelt, P. McPeters, R. TI Evaluation of ozone total column measurements by the Ozone Monitoring Instrument using a data assimilation system SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID AURA SATELLITE; EOS MLS; CALIBRATION; PROFILES AB On 15 July 2004, the Ozone Monitoring Instrument (OMI) on board the EOS Aura mission was launched. One of OMI's priorities is to continue the record of high spatial resolution ozone total column measurements provided by the various Total Ozone Mapping Spectrometer (TOMS) instruments since 1978. To this end, it is essential to estimate the errors affecting OMI ozone total column measurements and to see whether the actual accuracy is consistent with estimated values before launch. In this paper, data assimilation techniques are used to create a large comparison data set composed of ozone analyses resulting from assimilation of standard meteorological observations and ozone retrievals (independent of OMI measurements) into a numerical weather prediction model. This data set provides excellent global coverage and temporal resolution, not limited by the spatial and temporal distribution of other satellite or ground based information. The accuracy of the analyses is evaluated against ozone total column retrievals from Brewer measurements, while the assimilated ozone data set is compared to ozone predictions made using the ECMWF model, to check for the presence of bias. The OMI ozone column measurements considered here are obtained with the TOMS-V8 total ozone algorithm and denoted as OMTO3 columns. They are compared with simulated OMI ozone columns, i.e., the quantities that the TOMS-V8 algorithm would retrieve in the case when the atmospheric ozone profile at a specific location and time is equal to the one prescribed by the analysis. In this way, the comparison is statistically robust even when data acquired during a relatively short temporal interval or over a relatively small geographical area only is considered. A discussion of relevant error sources (including systematic components), vertical resolution, and contributions from prior information is provided. Special attention is given to determining the importance of representativeness errors. Our results show a solar zenith angle (SZA) dependence of the bias between measured and simulated OMI columns. This is believed to be due to moderate nonlinearity of the observation forward model and its effects on our definition of simulated OMI columns at high SZA. In view of these findings the final results of the intercomparison methodology used in this paper are obtained from OMI ozone columns retrieved using the basic implementation of the TOMS-V8 algorithm applied to measurements taken at SZA not exceeding 70 degrees. Intercomparison results between measured and simulated OMI ozone columns at SZA less than 70 degrees show a relative bias of -3.2 +/- 3.1% and a root-mean-square error of 4.5 +/- 1.5%. The resulting bias is consistent with available estimates of the bias of OMTO3 columns with respect to SBUV/2 between 60 degrees S and 60 degrees N, as well as with respect to global Dobson data and Brewer measurements between 30 degrees N and 60 degrees N. C1 [Migliorini, S.; Brugge, R.; O'Neill, A.] Univ Reading, Data Assimilat Res Ctr, Reading RG6 6BB, Berks, England. [Dobber, M.; Levelt, P.] Royal Netherlands Meteorol Inst, KNMI, NL-3730 AE De Bilt, Netherlands. [McPeters, R.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Fioletov, V.] Environm Canada, Toronto, ON M3H 5T4, Canada. RP Migliorini, S (reprint author), Univ Reading, Data Assimilat Res Ctr, POB 243, Reading RG6 6BB, Berks, England. EM s.migliorini@reading.ac.uk RI Migliorini, Stefano/J-5211-2012; McPeters, Richard/G-4955-2013 OI Migliorini, Stefano/0000-0002-9489-9867; McPeters, Richard/0000-0002-8926-8462 NR 29 TC 3 Z9 4 U1 1 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 10 PY 2008 VL 113 IS D15 AR D15S21 DI 10.1029/2007JD008779 PG 19 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 300MM UT WOS:000255827900001 ER PT J AU Baloga, SM Glaze, LS AF Baloga, S. M. Glaze, L. S. TI A self-replication model for long channelized lava flows on the Mars plains SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID WIDTH BEHAVIOR; VOLCANO; RHEOLOGY; PAHOEHOE; DYNAMICS; HAWAII; EMPLACEMENT; TOPOGRAPHY; BASALT; MONS AB A model is presented for channelized lava flows emplaced by a self-replicating, levee-building process over long distances on the plains of Mars. Such flows may exhibit morphologic evidence of stagnation, overspills, and upstream breakouts. However, these processes do not inhibit the formation and persistence of a prominent central channel that can often be traced for more than 100 km. The two central assumptions of the self-replication model are (1) the flow advances at the average upstream velocity of the molten core and (2) the fraction of the lava that travels faster than the average upstream velocity forms stationary margins in the advancing distal zone to preserve the self-replication process. For an exemplary 300 km long flow north of Pavonis Mons, the model indicates that similar to 8 m of crust must have formed during emplacement, as determined from the channel and levee dimensions. When combined with independent thermal dynamic estimates for the crustal growth rate, relatively narrow constraints are obtained for the flow rate (2250 m(3) s(-1)), emplacement duration (600 d), and the lava viscosity of the molten interior (10(6) Pa s). Minor, transient overspills and breakouts increase the emplacement time by only a factor of 2. The primary difference between the prodigious channelized Martian flows and their smaller terrestrial counterparts is that high volumetric flow rates must have persisted for many hundreds of days on Mars, in contrast to a few hours or days on Earth. C1 [Baloga, S. M.] Proxemy Res, Gaithersburg, MD 20882 USA. [Glaze, L. S.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Baloga, SM (reprint author), Proxemy Res, 20528 Farcroft Lane, Gaithersburg, MD 20882 USA. EM steve@proxemy.com RI Glaze, Lori/D-1314-2012 NR 41 TC 14 Z9 14 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9097 EI 2169-9100 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD MAY 10 PY 2008 VL 113 IS E5 AR E05003 DI 10.1029/2007JE002954 PG 15 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 300NC UT WOS:000255829600001 ER PT J AU Nakano, S Ueno, G Ebihara, Y Fok, MC Ohtani, S Brandt, PC Mitchell, DG Keika, K Higuchi, T AF Nakano, S. Ueno, G. Ebihara, Y. Fok, M. -C. Ohtani, S. Brandt, P. C. Mitchell, D. G. Keika, K. Higuchi, T. TI A method for estimating the ring current structure and the electric potential distribution using energetic neutral atom data assimilation SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID AMPTE/CCE-CHEM MEASUREMENTS; PLASMA SHEET; MODEL; IMAGE; SUBSTORMS; TRANSPORT; IONS AB We present a technique for estimating ring current ion distributions and electric potential in the inner magnetosphere by incorporating data from the High-Energy Neutral Atom (HENA) imager on the IMAGE satellite into a kinetic ring current model in the context of data assimilation. Data assimilation is an approach which adjusts a physics-based model according to differences with observations. We perform the data assimilation using the particle filter (PF) which is applicable to high-dimensional systems and observations with relatively low computational cost. In the present technique, the magnetospheric electric potential distribution is represented by the sum of a Volland-Stern field and a deviation, and the deviation is improved in the assimilation process. The ring current ion distribution is then determined from the electric potential distribution. The method is tested by assimilating artificial data generated by another simulation. The results demonstrate that the ring current ion distribution is successfully reconstructed by the proposed algorithm and that the distorted structures of the electric potential distribution are also well reproduced. An example to illustrate how the present technique could be applied for assimilating a real IMAGE/HENA data set is also demonstrated. This technique provides a useful tool for investigating the global dynamic structure of ring current and electric potential. C1 [Nakano, S.; Ueno, G.; Higuchi, T.] Inst Stat Math, Res Org Informat & Syst, Minato Ku, Tokyo 1068569, Japan. [Ohtani, S.; Brandt, P. C.; Mitchell, D. G.] Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. [Ebihara, Y.] Nagoya Univ, Inst Adv Res, Chikusa Ku, Nagoya, Aichi 4648601, Japan. [Fok, M. -C.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Keika, K.] Austrian Acad Sci, Space Res Inst, A-8042 Graz, Austria. RP Nakano, S (reprint author), Inst Stat Math, Res Org Informat & Syst, Minato Ku, 4-6-7 Minami Azabu, Tokyo 1068569, Japan. EM shiny@ism.ac.jp; gen@ism.ac.jp; ebihara@stelab.nagoya-u.ac.jp; mei-ching.h.fok@nasa.gov; shin.ohtani@jhuapl.edu; pontus.brandt@jhuapl.edu; don.mitchell@jhuapl.edu; kunihiro.keika@oeaw.ac.at; higuchi@ism.ac.jp RI Fok, Mei-Ching/D-1626-2012; Ebihara, Yusuke/D-1638-2013; Ohtani, Shinichi/E-3914-2016; Brandt, Pontus/N-1218-2016; OI Ebihara, Yusuke/0000-0002-2293-1557; Ohtani, Shinichi/0000-0002-9565-6840; Brandt, Pontus/0000-0002-4644-0306; Nakano, Shin'ya/0000-0003-0772-4610 NR 37 TC 10 Z9 10 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9380 EI 2169-9402 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAY 10 PY 2008 VL 113 IS A5 AR A05208 DI 10.1029/2006JA011853 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 300NK UT WOS:000255830500001 ER PT J AU Alexander, MJ Gille, J Cavanaugh, C Coffey, M Craig, C Eden, T Francis, G Halvorson, C Hannigan, J Khosravi, R Kinnison, D Lee, H Massie, S Nardi, B Barnett, J Hepplewhite, C Lambert, A Dean, V AF Alexander, M. J. Gille, J. Cavanaugh, C. Coffey, M. Craig, C. Eden, T. Francis, G. Halvorson, C. Hannigan, J. Khosravi, R. Kinnison, D. Lee, H. Massie, S. Nardi, B. Barnett, J. Hepplewhite, C. Lambert, A. Dean, V. TI Global estimates of gravity wave momentum flux from High Resolution Dynamics Limb Sounder observations SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID STRATOSPHERIC MOUNTAIN WAVES; SATELLITE-OBSERVATIONS; LATITUDINAL VARIATIONS; UARS MLS; VARIANCE; SPECTRUM; ATMOSPHERE; PARAMETERIZATION; TEMPERATURES; WAVELENGTH AB High Resolution Dynamics Limb Sounder (HIRDLS) temperature profiles are analyzed to derive global properties of gravity waves. We describe a wavelet analysis technique that determines covarying wave temperature amplitude in adjacent temperature profile pairs, the wave vertical wavelength as a function of height, and the horizontal wave number along the line joining each profile pair. The analysis allows a local estimate of the magnitude of gravity wave momentum flux as a function of geographic location and height on a daily basis. We examine global distributions of these gravity wave properties in the monthly mean and on an individual day, and we also show sample instantaneous wave events observed by HIRDLS. The results are discussed in terms of previous satellite and radiosonde observational analyses and middle atmosphere general circulation model studies that parameterize gravity wave effects on the mean flow. The high vertical and horizontal resolution afforded by the HIRDLS measurements allows the analysis of a wider range of wave vertical and horizontal wavelengths than previous studies and begins to show individual wave events associated with mountains and convection in high detail. Mountain wave observations show clear propagation to altitudes in the mesosphere. C1 [Alexander, M. J.] NWRA, Colorado Res Associates Div, Boulder, CO 80301 USA. [Gille, J.; Dean, V.] Univ Colorado, Ctr Limb Atmospher Sounding, Boulder, CO 80309 USA. [Cavanaugh, C.; Coffey, M.; Craig, C.; Eden, T.; Francis, G.; Halvorson, C.; Hannigan, J.; Khosravi, R.; Kinnison, D.; Massie, S.; Nardi, B.] Natl Ctr Atmospher Res, Boulder, CO 80307 USA. [Barnett, J.; Hepplewhite, C.] Univ Oxford, Clarendon Lab, Oxford OX1 3PU, England. [Lambert, A.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Alexander, MJ (reprint author), NWRA, Colorado Res Associates Div, 3380 Mitchell Lane, Boulder, CO 80301 USA. EM alexand@cora.nwra.com NR 35 TC 112 Z9 114 U1 5 U2 17 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 9 PY 2008 VL 113 IS D15 AR D15S18 DI 10.1029/2007JD008807 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 300ML UT WOS:000255827800003 ER PT J AU Froidevaux, L Jiang, YB Lambert, A Livesey, NJ Read, WG Waters, JW Browell, EV Hair, JW Avery, MA Mcgee, TJ Twigg, LW Sumnicht, GK Jucks, KW Margitan, JJ Sen, B Stachnik, RA Toon, GC Bernath, PF Boone, CD Walker, KA Filipiak, MJ Harwood, RS Fuller, RA Manney, GL Schwartz, MJ Daffer, WH Drouin, BJ Cofield, RE Cuddy, DT Jarnot, RF Knosp, BW Perun, VS Snyder, WV Stek, PC Thurstans, RP Wagner, PA AF Froidevaux, L. Jiang, Y. B. Lambert, A. Livesey, N. J. Read, W. G. Waters, J. W. Browell, E. V. Hair, J. W. Avery, M. A. Mcgee, T. J. Twigg, L. W. Sumnicht, G. K. Jucks, K. W. Margitan, J. J. Sen, B. Stachnik, R. A. Toon, G. C. Bernath, P. F. Boone, C. D. Walker, K. A. Filipiak, M. J. Harwood, R. S. Fuller, R. A. Manney, G. L. Schwartz, M. J. Daffer, W. H. Drouin, B. J. Cofield, R. E. Cuddy, D. T. Jarnot, R. F. Knosp, B. W. Perun, V. S. Snyder, W. V. Stek, P. C. Thurstans, R. P. Wagner, P. A. TI Validation of Aura Microwave Limb Sounder stratospheric ozone measurements SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID HALOGEN OCCULTATION EXPERIMENT; EOS MLS; REMOTE MEASUREMENTS; SATELLITE; PROFILES; SYSTEM; SPECTROMETER; RETRIEVAL; QUALITY; MODEL AB The Earth Observing System (EOS) Microwave Limb Sounder (MLS) aboard the Aura satellite has provided essentially daily global measurements of ozone (O-3) profiles from the upper troposphere to the upper mesosphere since August of 2004. This paper focuses on validation of the MLS stratospheric standard ozone product and its uncertainties, as obtained from the 240 GHz radiometer measurements, with a few results concerning mesospheric ozone. We compare average differences and scatter from matched MLS version 2.2 profiles and coincident ozone profiles from other satellite instruments, as well as from aircraft lidar measurements taken during Aura Validation Experiment (AVE) campaigns. Ozone comparisons are also made between MLS and balloon-borne remote and in situ sensors. We provide a detailed characterization of random and systematic uncertainties for MLS ozone. We typically find better agreement in the comparisons using MLS version 2.2 ozone than the version 1.5 data. The agreement and the MLS uncertainty estimates in the stratosphere are often of the order of 5%, with values closer to 10% (and occasionally 20%) at the lowest stratospheric altitudes, where small positive MLS biases can be found. There is very good agreement in the latitudinal distributions obtained from MLS and from coincident profiles from other satellite instruments, as well as from aircraft lidar data along the MLS track. C1 [Froidevaux, L.; Jiang, Y. B.; Lambert, A.; Livesey, N. J.; Read, W. G.; Waters, J. W.; Margitan, J. J.; Sen, B.; Stachnik, R. A.; Toon, G. C.; Fuller, R. A.; Manney, G. L.; Schwartz, M. J.; Daffer, W. H.; Drouin, B. J.; Cofield, R. E.; Cuddy, D. T.; Jarnot, R. F.; Knosp, B. W.; Perun, V. S.; Snyder, W. V.; Stek, P. C.; Thurstans, R. P.; Wagner, P. A.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Browell, E. V.; Hair, J. W.; Avery, M. A.] NASA, Langley Res Ctr, Hampton, VA 23681 USA. [Mcgee, T. J.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Twigg, L. W.; Sumnicht, G. K.] Sci Syst Applicat Inc, Lanham, MD 20706 USA. [Jucks, K. W.] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. [Bernath, P. F.] Univ York, York YO10 5DD, N Yorkshire, England. [Boone, C. D.; Walker, K. A.] Univ Waterloo, Waterloo, ON N2L 3G1, Canada. [Bernath, P. F.; Boone, C. D.; Walker, K. A.] Univ Toronto, Toronto, ON, Canada. [Filipiak, M. J.; Harwood, R. S.] Univ Edinburgh, Old Coll, Edinburgh EH8 9YL, Midlothian, Scotland. [Manney, G. L.] New Mexico Inst Min & Technol, Socorro, NM 87801 USA. RP Froidevaux, L (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM lucien.froidevaux@jpl.nasa.gov RI Bernath, Peter/B-6567-2012; McGee, Thomas/G-4951-2013; Schwartz, Michael/F-5172-2016 OI Bernath, Peter/0000-0002-1255-396X; Schwartz, Michael/0000-0001-6169-5094 NR 56 TC 147 Z9 148 U1 1 U2 14 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 9 PY 2008 VL 113 IS D15 AR D15S20 DI 10.1029/2007JD008771 PG 24 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 300ML UT WOS:000255827800002 ER PT J AU Vasilkov, A Joiner, J Spurr, R Bhartia, PK Levelt, P Stephens, G AF Vasilkov, Alexander Joiner, Joanna Spurr, Robert Bhartia, Pawan K. Levelt, Pieternel Stephens, Graeme TI Evaluation of the OMI cloud pressures derived from rotational Raman scattering by comparisons with other satellite data and radiative transfer simulations SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID BACKSCATTER ULTRAVIOLET MEASUREMENTS; UV MEASUREMENTS; TRANSFER MODEL; OZONE; ATMOSPHERE; RETRIEVAL; PARAMETERS AB In this paper we examine differences between cloud pressures retrieved from the Ozone Monitoring Instrument (OMI) using the ultraviolet rotational Raman scattering (RRS) algorithm and those from the thermal infrared (IR) Aqua/MODIS. Several cloud data sets are currently being used in OMI trace gas retrieval algorithms including climatologies based on IR measurements and simultaneous cloud parameters derived from OMI. From a validation perspective, it is important to understand the OMI retrieved cloud parameters and how they differ with those derived from the IR. To this end, we perform radiative transfer calculations to simulate the effects of different geophysical conditions on the OMI RRS cloud pressure retrievals. We also quantify errors related to the use of the Mixed Lambert-Equivalent Reflectivity (MLER) concept as currently implemented of the OMI algorithms. Using properties from the Cloudsat radar and MODIS, we show that radiative transfer calculations support the following: (1) The MLER model is adequate for single-layer optically thick, geometrically thin clouds, but can produce significant errors in estimated cloud pressure for optically thin clouds. (2) In a two-layer cloud, the RRS algorithm may retrieve a cloud pressure that is either between the two cloud decks or even beneath the top of the lower cloud deck because of scattering between the cloud layers; the retrieved pressure depends upon the viewing geometry and the optical depth of the upper cloud deck. (3) Absorbing aerosol in and above a cloud can produce significant errors in the retrieved cloud pressure. (4) The retrieved RRS effective pressure for a deep convective cloud will be significantly higher than the physical cloud top pressure derived with thermal IR. C1 [Vasilkov, Alexander] Sci Syst & Applicat Inc, Lanham, MD 20706 USA. [Joiner, Joanna; Bhartia, Pawan K.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Spurr, Robert] RT Solut Inc, Cambridge, MA 02138 USA. [Levelt, Pieternel] Royal Netherlands Meteorol Inst, KNMI, NL-3730 AE De Bilt, Netherlands. [Stephens, Graeme] Colorado State Univ, Ft Collins, CO 80523 USA. RP Vasilkov, A (reprint author), Sci Syst & Applicat Inc, Lanham, MD 20706 USA. EM alexander_vassilkov@ssaihq.com RI Joiner, Joanna/D-6264-2012 NR 29 TC 46 Z9 46 U1 0 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 9 PY 2008 VL 113 IS D15 AR D15S19 DI 10.1029/2007JD008689 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 300ML UT WOS:000255827800001 ER PT J AU Knoll, AH Jolliff, BL Farrand, WH Bell, JF Clark, BC Gellert, R Golombek, MP Grotzinger, JP Herkenhoff, KE Johnson, JR McLennan, SM Morris, R Squyres, SW Sullivan, R Tosca, NJ Yen, A Learner, Z AF Knoll, Andrew H. Jolliff, Brad L. Farrand, William H. Bell, James F., III Clark, Benton C. Gellert, Ralf Golombek, M. P. Grotzinger, John P. Herkenhoff, Kenneth E. Johnson, Jeffrey R. McLennan, Scott M. Morris, Richard Squyres, Steven W. Sullivan, Robert Tosca, Nicholas J. Yen, Albert Learner, Zoe TI Veneers, rinds, and fracture fills: Relatively late alteration of sedimentary rocks at Meridiani Planum, Mars SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID OPPORTUNITY ROVER; BURNS FORMATION; WATER; MINERALOGY; CHEMISTRY; OUTCROPS; ORIGIN; CRATER; DUST; SOIL AB Veneers and thicker rinds that coat outcrop surfaces and partially cemented fracture fills formed perpendicular to bedding document relatively late stage alteration of ancient sedimentary rocks at Meridiani Planum, Mars. The chemistry of submillimeter thick, buff-colored veneers reflects multiple processes at work since the establishment of the current plains surface. Veneer composition is dominated by the mixing of silicate-rich dust and sulfate-rich outcrop surface, but it has also been influenced by mineral precipitation, including NaCl, and possibly by limited physical or chemical weathering of sulfate minerals. Competing processes of chemical alteration (perhaps mediated by thin films of water or water vapor beneath blanketing soils) and sandblasting of exposed outcrop surfaces determine the current distribution of veneers. Dark-toned rinds several millimeters thick reflect more extensive surface alteration but also indicate combined dust admixture, halite precipitation, and possible minor sulfate removal. Cemented fracture fills that are differentially resistant to erosion occur along the margins of linear fracture systems possibly related to impact. These appear to reflect limited groundwater activity along the margins of fractures, cementing mechanically introduced fill derived principally from outcrop rocks. The limited thickness and spatial distribution of these three features suggest that aqueous activity has been rare and transient or has operated at exceedingly low rates during the protracted interval since outcropping Meridiani strata were exposed on the plains surface. C1 [Knoll, Andrew H.; Tosca, Nicholas J.] Harvard Univ, Dept Organism & Evolut Biol, Cambridge, MA 02138 USA. [Jolliff, Brad L.] Washington Univ, Dept Earth & Planetary Sci, St Louis, MO 63130 USA. [Farrand, William H.] Space Sci Inst, Boulder, CO 80301 USA. [Bell, James F., III; Squyres, Steven W.; Sullivan, Robert; Learner, Zoe] Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. [Clark, Benton C.] Lockheed Martin Corp, Littleton, CO USA. [Gellert, Ralf] Max Planck Inst Chem, D-55128 Mainz, Germany. [Gellert, Ralf] Univ Guelph, Dept Phys, Guelph, ON N1G 2W1, Canada. [Golombek, M. P.; Yen, Albert] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Grotzinger, John P.] CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA. [Herkenhoff, Kenneth E.; Johnson, Jeffrey R.] US Geol Survey, Astrogeol Team, Flagstaff, AZ 86001 USA. [McLennan, Scott M.; Tosca, Nicholas J.] SUNY Stony Brook, Dept Geosci, Stony Brook, NY 11794 USA. [Morris, Richard] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Knoll, AH (reprint author), Harvard Univ, Dept Organism & Evolut Biol, 26 Oxford St, Cambridge, MA 02138 USA. RI Johnson, Jeffrey/F-3972-2015 NR 46 TC 29 Z9 29 U1 0 U2 8 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9097 EI 2169-9100 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD MAY 8 PY 2008 VL 113 IS E6 AR E06S16 DI 10.1029/2007JE002949 PG 27 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 300NE UT WOS:000255829800001 ER PT J AU Kjaergaard, HG Garden, AL Chaban, GM Gerber, RB Matthews, DA Stanton, JF AF Kjaergaard, Henrik G. Garden, Anna L. Chaban, Galina M. Gerber, R. Benny Matthews, Devin A. Stanton, John F. TI Calculation of vibrational transition frequencies and intensities in water dimer: Comparison of different vibrational approaches SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID SELF-CONSISTENT-FIELD; AB-INITIO CALCULATIONS; GAUSSIAN-BASIS SETS; SIZE-SELECTED WATER; OVERTONE SPECTRA; INFRARED-SPECTROSCOPY; BAND INTENSITIES; ATMOSPHERIC CHEMISTRY; PERTURBATION-THEORY; SOLAR-RADIATION AB We have calculated frequencies and intensities of fundamental and overtone vibrational transitions in water and water dimer with use of different vibrational methods. We have compared results obtained with correlation-corrected vibrational self-consistent-field theory and vibrational second-order perturbation theory both using normal modes and finally with a harmonically coupled anharmonic oscillator local mode model including CH-stretching and HOH-bending local modes. The coupled cluster with singles, doubles, and perturbative triples ab initio method with augmented correlation-consistent triple-zeta Dunning and atomic natural orbital basis sets has been used to obtain the necessary potential energy and dipole moment surfaces. We identify the strengths and weaknesses of these different vibrational approaches and compare our results to the available experimental results. C1 [Kjaergaard, Henrik G.; Garden, Anna L.] Univ Otago, Dept Chem, Dunedin 9054, New Zealand. [Kjaergaard, Henrik G.; Garden, Anna L.] Aarhus Univ, Dept Chem, Ctr Theoret Chem, Lundbeck Fdn, DK-8000 Aarhus, Denmark. [Chaban, Galina M.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. [Gerber, R. Benny] Univ Calif Irvine, Dept Chem, Irvine, CA 92697 USA. [Gerber, R. Benny] Hebrew Univ Jerusalem, Dept Phys Chem, IL-91904 Jerusalem, Israel. [Gerber, R. Benny] Hebrew Univ Jerusalem, Fritz Haber Res Ctr, IL-91904 Jerusalem, Israel. [Matthews, Devin A.; Stanton, John F.] Univ Texas Austin, Ctr Theoret Chem, Dept Chem, Austin, TX 78712 USA. [Matthews, Devin A.; Stanton, John F.] Univ Texas Austin, Ctr Theoret Chem, Dept Biochem, Austin, TX 78712 USA. RP Kjaergaard, HG (reprint author), Univ Otago, Dept Chem, POB 56, Dunedin 9054, New Zealand. EM henrik@chemistry.otago.ac.nz RI Kjaergaard, Henrik /H-4333-2014 OI Kjaergaard, Henrik /0000-0002-7275-8297 NR 87 TC 107 Z9 110 U1 1 U2 80 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD MAY 8 PY 2008 VL 112 IS 18 BP 4324 EP 4335 DI 10.1021/jp710066f PG 12 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 295PM UT WOS:000255486400021 PM 18407701 ER PT J AU Orton, GS Yanamandra-Fisher, PA Fisher, BM Friedson, AJ Parrish, PD Nelson, JF Bauermeister, AS Fletcher, L Gezari, DY Varosi, F Tokunaga, AT Caldwell, J Baines, KH Hora, JL Ressler, ME Fujiyoshi, T Fuse, T Hagopian, H Martin, TZ Bergstralh, JT Howett, C Hoffmann, WF Deutsch, LK Van Cleve, JE Noe, E Adams, JD Kassis, M Tollestrup, E AF Orton, Glenn S. Yanamandra-Fisher, Padma A. Fisher, Brendan M. Friedson, A. James Parrish, Paul D. Nelson, Jesse F. Bauermeister, Amber Swenson Fletcher, Leigh Gezari, Daniel Y. Varosi, Frank Tokunaga, Alan T. Caldwell, John Baines, Kevin H. Hora, Joseph L. Ressler, Michael E. Fujiyoshi, Takuya Fuse, Tetsuharu Hagopian, Hagop Martin, Terry Z. Bergstralh, Jay T. Howett, Carly Hoffmann, William F. Deutsch, Lynne K. Van Cleve, Jeffrey E. Noe, Eldar Adams, Joseph D. Kassis, Marc Tollestrup, Eric TI Semi-annual oscillations in Saturn's low-latitude stratospheric temperatures SO NATURE LA English DT Article ID JUPITERS STRATOSPHERE AB Observations of oscillations of temperature and wind in planetary atmospheres provide a means of generalizing models for atmospheric dynamics in a diverse set of planets in the Solar System and elsewhere. An equatorial oscillation similar to one in the Earth's atmosphere(1,2) has been discovered in Jupiter(3-6). Here we report the existence of similar oscillations in Saturn's atmosphere, from an analysis of over two decades of spatially resolved observations of its 7.8-mu m methane and 12.2-mu m ethane stratospheric emissions, where we compare zonal- mean stratospheric brightness temperatures at planetographic latitudes of 3.6 degrees and 15.5 degrees in both the northern and the southern hemispheres. These results support the interpretation of vertical and meridional variability of temperatures in Saturn's stratosphere(7) as a manifestation of a wave phenomenon similar to that on the Earth and in Jupiter. The period of this oscillation is 14.8+/-1.2 terrestrial years, roughly half of Saturn's year, suggesting the influence of seasonal forcing, as is the case with the Earth's semi- annual oscillation(1). C1 [Orton, Glenn S.; Yanamandra-Fisher, Padma A.; Fisher, Brendan M.; Friedson, A. James; Fletcher, Leigh; Baines, Kevin H.; Ressler, Michael E.; Martin, Terry Z.; Noe, Eldar] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Parrish, Paul D.] Univ Edinburgh, Sch Geosci, Edinburgh EH9 3JN, Midlothian, Scotland. [Nelson, Jesse F.] Univ Maine, Dept Phys & Astron, Orono, ME 04469 USA. [Bauermeister, Amber Swenson] Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. [Gezari, Daniel Y.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Varosi, Frank] Univ Florida, Dept Astron, Bryant Space Sci Ctr 211, Gainesville, FL 32611 USA. [Tokunaga, Alan T.] Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA. [Caldwell, John] York Univ, Dept Phys & Astron, Toronto, ON M3J 1P3, Canada. [Hora, Joseph L.] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. [Fujiyoshi, Takuya; Fuse, Tetsuharu] Natl Inst Nat Sci, Natl Astron Observ Japan, Subaru Telescope, Hilo, HI 96720 USA. [Hagopian, Hagop] Univ Calif Los Angeles, Dept Comp Sci, Los Angeles, CA 90095 USA. [Bergstralh, Jay T.] Langley Res Ctr, Hampton, VA 23681 USA. [Howett, Carly] Univ Oxford, Clarendon Lab, Oxford OX1 3PU, England. [Hoffmann, William F.] Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. [Van Cleve, Jeffrey E.] Ball Aerosp & Technol Corp, Civil Space Syst, Boulder, CO 80306 USA. [Adams, Joseph D.] Dept Radiophys & Space Res, Ithaca, NY 14853 USA. [Kassis, Marc] WM Keck Observ, Kamuela, HI 96743 USA. [Tollestrup, Eric] NASA, Infrared Telescope Facil, Inst Astron, Hilo, HI 96822 USA. RP Orton, GS (reprint author), CALTECH, Jet Prop Lab, MS 169-237,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM glenn.orton@jpl.nasa.gov RI Fletcher, Leigh/D-6093-2011; OI Fletcher, Leigh/0000-0001-5834-9588; Hora, Joseph/0000-0002-5599-4650 NR 12 TC 44 Z9 44 U1 0 U2 6 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD MAY 8 PY 2008 VL 453 IS 7192 BP 196 EP 199 DI 10.1038/nature06897 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 297BP UT WOS:000255592400033 PM 18464736 ER PT J AU Fouchet, T Guerlet, S Strobel, DF Simon-Miller, AA Bezard, B Flasar, FM AF Fouchet, T. Guerlet, S. Strobel, D. F. Simon-Miller, A. A. Bezard, B. Flasar, F. M. TI An equatorial oscillation in Saturn's middle atmosphere SO NATURE LA English DT Article ID QUASI-BIENNIAL OSCILLATION; JUPITERS STRATOSPHERE; MODEL; TEMPERATURES; TROPOSPHERE; PLANETS; SYSTEM; WINDS; TIME AB The middle atmospheres of planets are driven by a combination of radiative heating and cooling, mean meridional motions, and vertically propagating waves ( which originate in the deep troposphere). It is very difficult to model these effects and, therefore, observations are essential to advancing our understanding of atmospheres. The equatorial stratospheres of Earth and Jupiter oscillate quasi- periodically on timescales of about two and four years, respectively, driven by wave- induced momentum transport(1-5). On Venus and Titan, waves originating from surface atmosphere interaction and inertial instability are thought to drive the atmosphere to rotate more rapidly than the surface ( superrotation). However, the relevant wave modes have not yet been precisely identified. Here we report infrared observations showing that Saturn has an equatorial oscillation like those found on Earth and Jupiter, as well as a mid- latitude subsidence that may be associated with the equatorial motion. The latitudinal extent of Saturn's oscillation shows that it obeys the same basic physics as do those on Earth and Jupiter. Future highly resolved observations of the temperature profile together with modelling of these three different atmospheres will allow us determine the wave mode, the wavelength and the wave amplitude that lead to middle atmosphere oscillation. C1 [Fouchet, T.; Guerlet, S.; Bezard, B.] Univ Paris 06, Observ Paris, CNRS, LESIA, F-92195 Meudon, France. [Strobel, D. F.] Johns Hopkins Univ, Dept Earth & Planetary Sci, Baltimore, MD 21218 USA. [Strobel, D. F.] Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. [Simon-Miller, A. A.; Flasar, F. M.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Fouchet, T (reprint author), Univ Paris 06, Observ Paris, CNRS, LESIA, F-92195 Meudon, France. EM thierry.fouchet@obspm.fr RI Simon, Amy/C-8020-2012; Flasar, F Michael/C-8509-2012; Fouchet, Thierry/C-6374-2017 OI Simon, Amy/0000-0003-4641-6186; Fouchet, Thierry/0000-0001-9040-8285 NR 23 TC 48 Z9 48 U1 0 U2 7 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 EI 1476-4687 J9 NATURE JI Nature PD MAY 8 PY 2008 VL 453 IS 7192 BP 200 EP 202 DI 10.1038/nature06912 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 297BP UT WOS:000255592400034 PM 18464737 ER PT J AU Baggio, L Bignotto, M Bonaldi, M Cerdonio, M De Rosa, M Falferi, P Fattori, S Fortini, P Giusfredi, G Inguscio, M Liguori, N Longo, S Marin, F Mezzena, R Mion, A Ortolan, A Poggi, S Prodi, GA Re, V Salemi, F Soranzo, G Taffarello, L Vedovato, G Vinante, A Vitale, S Zendri, JP Abbott, B Abbott, R Adhikari, R Agresti, J Ajith, P Allen, B Amin, R Anderson, SB Anderson, WG Arain, M Araya, M Armandula, H Ashley, M Aston, S Aufmuth, P Aulbert, C Babak, S Ballmer, S Bantilan, H Barish, BC Barker, C Barker, D Barr, B Barriga, P Barton, MA Bayer, K Belczynski, K Betzwieser, J Beyersdorf, PT Bhawal, B Bilenko, IA Billingsley, G Biswas, R Black, E Blackburn, K Blackburn, L Blair, D Bland, B Bogenstahl, J Bogue, L Bork, R Boschi, V Bose, S Brady, PR Braginsky, VB Brau, JE Brinkmann, M Brooks, A Brown, DA Bullington, A Bunkowski, A Buonanno, A Burmeister, O Busby, D Butler, WE Byer, RL Cadonati, L Cagnoli, G Camp, JB Cannizzo, J Cannon, K Cantley, CA Cao, J Cardenas, L Carter, K Casey, MM Castaldi, G Cepeda, C Chalkley, E Charlton, P Chatterji, S Chelkowski, S Chen, Y Chiadini, F Chin, D Chin, E Chow, J Christensen, N Clark, J Cochrane, P Cokelaer, T Colacino, CN Coldwell, R Conte, R Cook, D Corbitt, T Coward, D Coyne, D Creighton, JDE Creighton, TD Croce, RP Crooks, DRM Cruise, AM Cumming, A Dalrymple, J D'Ambrosio, E Danzmann, K Davies, G DeBbra, D Degallaix, J Degree, M Demma, T Dergachev, V Desai, S DeSalvo, R Dhurandhar, S Diaz, M Dickson, J Di Credico, A Diederichs, G Dietz, A Doomes, EE Drever, RWP Dumas, JC Dupuis, RJ Dwyer, JG Ehrens, P Espinoza, E Etzel, T Evans, M Evans, T Fairhurst, S Fan, Y Fazi, D Fejer, MM Finn, LS Fiumara, V Fotopoulos, N Franzen, A Franzen, KY Freise, A Frey, R Fricke, T Fritschel, P Frolov, VV Fyffe, M Galdi, V Ganezer, KS Garofoli, J Gholami, I Giaime, JA Giampanis, S Giardina, KD Goda, K Goetz, E Goggin, LM Gonzalez, G Gossler, S Grant, A Gras, S Gray, C Gray, M Greenhalgh, J Gretarsson, AM Grosso, R Grote, H Grunewald, S Guenther, M Gustafson, R Hage, B Hammer, D Hanna, C Hanson, J Harms, J Harry, G Harstad, E Hayler, T Heefner, J Heng, IS Heptonstall, A Heurs, M Hewitson, M Hild, S Hirose, E Hoak, D Hosken, D Hough, J Howell, E Hoyland, D Huttner, SH Ingram, D Innerhofer, E Ito, M Itoh, Y Ivanov, A Jackrel, D Johnson, B Johnson, WW Jones, DI Jones, G Jones, R Ju, L Kalmus, P Kalogera, V Kasprzyk, D Katsavounidis, E Kawabe, K Kawamura, S Kawazoe, F Kells, W Keppel, DG Khalili, FY Kim, C King, P Kissel, JS Klimenko, S Kokeyama, K Kondrashov, V Kopparapu, RK Kozak, D Krishnan, B Kwee, P Lam, PK Landry, M Lantz, B Lazzarini, A Lee, B Lei, M Leiner, J Leonhardt, V Leonor, I Libbrecht, K Lindquist, P Lockerbie, NA Longo, M Lormand, M Lubinski, M Luck, H Machenschalk, B MacInnis, M Mageswaran, M Mailand, K Malec, M Mandic, V Marano, S Marka, S Markowitz, J Maros, E Martin, I Marx, JN Mason, K Matone, L Matta, V Mavalvala, N McCarthy, R McClelland, DE McGuire, SC McHugh, M McKenzie, K McNabb, JWC McWilliams, S Meier, T Melissinos, A Mendell, G Mercer, RA Meshkov, S Messenger, CJ Meyers, D Mikhailov, E Mitra, S Mitrofanov, VP Mitselmakher, G Mittleman, R Miyakawa, O Mohanty, S Moreno, G Mossavi, K MowLowry, C Moylan, A Mudge, D Mueller, G Mukherjee, S Muller-Ebhardt, H Munch, J Murray, P Myers, E Myers, J Nash, T Newton, G Nishizawa, A Nocera, F Numata, K O'Reilly, B O'Shaughnessy, R Ottaway, DJ Overmier, H Owen, BJ Pan, Y Papa, MA Parameshwaraiah, V Parameswariah, C Patel, P Pedraza, M Penn, S Pierro, V Pinto, IM Pitkin, M Pletsch, H Plissi, MV Postiglione, F Prix, R Quetschke, V Raab, F Rabeling, D Radkins, H Rahkola, R Rainer, N Rakhmanov, M Ramsunder, M Rawlins, K Ray-Majumder, S Regimbau, T Rehbein, H Reid, S Reitze, DH Ribichini, L Riesen, R Riles, K Rivera, B Robertson, NA Robinson, C Robinson, EL Roddy, S Rodriguez, A Rogan, AM Rollins, J Romano, JD Romie, J Route, R Rowan, S Rudiger, A Ruet, L Russell, P Ryan, K Sakata, S Samidi, M de la Jordana, LS Sandberg, V Sanders, GH Sannibale, V Saraf, S Sarin, P Sathyaprakash, BS Sato, S Saulson, P Savage, R Savov, P Sazonov, A Schediwy, S Schilling, R Schnabel, R Schofield, R Schutz, BF Schwinberg, P Scott, SM Searle, AC Sears, B Seifert, F Sellers, D Sengupta, AS Shawhan, P Shoemaker, DH Sibley, A Siemens, X Sigg, D Sinha, S Sintes, AM Slagmolen, BJJ Slutsky, J Smith, JR Smith, MR Somiya, K Strain, KA Strom, DM Stuver, A Summerscales, TZ Sun, KX Sung, M Sutton, PJ Takahashi, H Tanner, DB Tarallo, M Taylor, R Taylor, R Thacker, J Thorne, KA Thorne, KS Thuring, A Tinto, M Tokmakov, KV Torres, C Torrie, C Traylor, G Trias, M Tyler, W Ugolini, D Ungarelli, C Urbanek, K Vahlbruch, H Vallisneri, M Van den Broeck, C van Putten, M Varvella, M Vass, S Vecchio, A Veitch, J Veitch, P Villar, A Vorvick, C Vyachanin, SP Waldman, SJ Wallace, L Ward, H Ward, R Watts, K Webber, D Weidner, A Weinert, M Weinstein, A Weiss, R Wen, S Wette, K Whelan, JT Whitbeck, DM Whitcomb, SE Whiting, BF Wiley, S Wilkinson, C Willems, PA Williams, L Willke, B Wilmut, I Winkler, W Wipf, CC Wise, S Wiseman, AG Woan, G Woods, D Wooley, R Worden, J Wu, W Yakushin, I Yamamoto, H Yan, Z Yoshida, S Yunes, N Zanolin, M Zhang, J Zhang, L Zhao, C Zotov, N Zucker, M zur Muhlen, H Zweizig, J AF Baggio, L. Bignotto, M. Bonaldi, M. Cerdonio, M. De Rosa, M. Falferi, P. Fattori, S. Fortini, P. Giusfredi, G. Inguscio, M. Liguori, N. Longo, S. Marin, F. Mezzena, R. Mion, A. Ortolan, A. Poggi, S. Prodi, G. A. Re, V. Salemi, F. Soranzo, G. Taffarello, L. Vedovato, G. Vinante, A. Vitale, S. Zendri, J. P. Abbott, B. Abbott, R. Adhikari, R. Agresti, J. Ajith, P. Allen, B. Amin, R. Anderson, S. B. Anderson, W. G. Arain, M. Araya, M. Armandula, H. Ashley, M. Aston, S. Aufmuth, P. Aulbert, C. Babak, S. Ballmer, S. Bantilan, H. Barish, B. C. Barker, C. Barker, D. Barr, B. Barriga, P. Barton, M. A. Bayer, K. Belczynski, K. Betzwieser, J. Beyersdorf, P. T. Bhawal, B. Bilenko, I. A. Billingsley, G. Biswas, R. Black, E. Blackburn, K. Blackburn, L. Blair, D. Bland, B. Bogenstahl, J. Bogue, L. Bork, R. Boschi, V. Bose, S. Brady, P. R. Braginsky, V. B. Brau, J. E. Brinkmann, M. Brooks, A. Brown, D. A. Bullington, A. Bunkowski, A. Buonanno, A. Burmeister, O. Busby, D. Butler, W. E. Byer, R. L. Cadonati, L. Cagnoli, G. Camp, J. B. Cannizzo, J. Cannon, K. Cantley, C. A. Cao, J. Cardenas, L. Carter, K. Casey, M. M. Castaldi, G. Cepeda, C. Chalkley, E. Charlton, P. Chatterji, S. Chelkowski, S. Chen, Y. Chiadini, F. Chin, D. Chin, E. Chow, J. Christensen, N. Clark, J. Cochrane, P. Cokelaer, T. Colacino, C. N. Coldwell, R. Conte, R. Cook, D. Corbitt, T. Coward, D. Coyne, D. Creighton, J. D. E. Creighton, T. D. Croce, R. P. Crooks, D. R. M. Cruise, A. M. Cumming, A. Dalrymple, J. D'Ambrosio, E. Danzmann, K. Davies, G. DeBbra, D. Degallaix, J. Degree, M. Demma, T. Dergachev, V. Desai, S. DeSalvo, R. Dhurandhar, S. Diaz, M. Dickson, J. Di Credico, A. Diederichs, G. Dietz, A. Doomes, E. E. Drever, R. W. P. Dumas, J-C Dupuis, R. J. Dwyer, J. G. Ehrens, P. Espinoza, E. Etzel, T. Evans, M. Evans, T. Fairhurst, S. Fan, Y. Fazi, D. Fejer, M. M. Finn, L. S. Fiumara, V. Fotopoulos, N. Franzen, A. Franzen, K. Y. Freise, A. Frey, R. Fricke, T. Fritschel, P. Frolov, V. V. Fyffe, M. Galdi, V. Ganezer, K. S. Garofoli, J. Gholami, I. Giaime, J. A. Giampanis, S. Giardina, K. D. Goda, K. Goetz, E. Goggin, L. M. Gonzalez, G. Gossler, S. Grant, A. Gras, S. Gray, C. Gray, M. Greenhalgh, J. Gretarsson, A. M. Grosso, R. Grote, H. Grunewald, S. Guenther, M. Gustafson, R. Hage, B. Hammer, D. Hanna, C. Hanson, J. Harms, J. Harry, G. Harstad, E. Hayler, T. Heefner, J. Heng, I. S. Heptonstall, A. Heurs, M. Hewitson, M. Hild, S. Hirose, E. Hoak, D. Hosken, D. Hough, J. Howell, E. Hoyland, D. Huttner, S. H. Ingram, D. Innerhofer, E. Ito, M. Itoh, Y. Ivanov, A. Jackrel, D. Johnson, B. Johnson, W. W. Jones, D. I. Jones, G. Jones, R. Ju, L. Kalmus, P. Kalogera, V. Kasprzyk, D. Katsavounidis, E. Kawabe, K. Kawamura, S. Kawazoe, F. Kells, W. Keppel, D. G. Khalili, F. Ya Kim, C. King, P. Kissel, J. S. Klimenko, S. Kokeyama, K. Kondrashov, V. Kopparapu, R. K. Kozak, D. Krishnan, B. Kwee, P. Lam, P. K. Landry, M. Lantz, B. Lazzarini, A. Lee, B. Lei, M. Leiner, J. Leonhardt, V. Leonor, I. Libbrecht, K. Lindquist, P. Lockerbie, N. A. Longo, M. Lormand, M. Lubinski, M. Lueck, H. Machenschalk, B. MacInnis, M. Mageswaran, M. Mailand, K. Malec, M. Mandic, V. Marano, S. Marka, S. Markowitz, J. Maros, E. Martin, I. Marx, J. N. Mason, K. Matone, L. Matta, V. Mavalvala, N. McCarthy, R. McClelland, D. E. McGuire, S. C. McHugh, M. McKenzie, K. McNabb, J. W. C. McWilliams, S. Meier, T. Melissinos, A. Mendell, G. Mercer, R. A. Meshkov, S. Messenger, C. J. Meyers, D. Mikhailov, E. Mitra, S. Mitrofanov, V. P. Mitselmakher, G. Mittleman, R. Miyakawa, O. Mohanty, S. Moreno, G. Mossavi, K. MowLowry, C. Moylan, A. Mudge, D. Mueller, G. Mukherjee, S. Mueller-Ebhardt, H. Munch, J. Murray, P. Myers, E. Myers, J. Nash, T. Newton, G. Nishizawa, A. Nocera, F. Numata, K. O'Reilly, B. O'Shaughnessy, R. Ottaway, D. J. Overmier, H. Owen, B. J. Pan, Y. Papa, M. A. Parameshwaraiah, V. Parameswariah, C. Patel, P. Pedraza, M. Penn, S. Pierro, V. Pinto, I. M. Pitkin, M. Pletsch, H. Plissi, M. V. Postiglione, F. Prix, R. Quetschke, V. Raab, F. Rabeling, D. Radkins, H. Rahkola, R. Rainer, N. Rakhmanov, M. Ramsunder, M. Rawlins, K. Ray-Majumder, S. Regimbau, T. Rehbein, H. Reid, S. Reitze, D. H. Ribichini, L. Riesen, R. Riles, K. Rivera, B. Robertson, N. A. Robinson, C. Robinson, E. L. Roddy, S. Rodriguez, A. Rogan, A. M. Rollins, J. Romano, J. D. Romie, J. Route, R. Rowan, S. Ruediger, A. Ruet, L. Russell, P. Ryan, K. Sakata, S. Samidi, M. de la Jordana, L. Sancho Sandberg, V. Sanders, G. H. Sannibale, V. Saraf, S. Sarin, P. Sathyaprakash, B. S. Sato, S. Saulson, Pr Savage, R. Savov, P. Sazonov, A. Schediwy, S. Schilling, R. Schnabel, R. Schofield, R. Schutz, B. F. Schwinberg, P. Scott, S. M. Searle, A. C. Sears, B. Seifert, F. Sellers, D. Sengupta, A. S. Shawhan, P. Shoemaker, D. H. Sibley, A. Siemens, X. Sigg, D. Sinha, S. Sintes, A. M. Slagmolen, B. J. J. Slutsky, J. Smith, J. R. Smith, M. R. Somiya, K. Strain, K. A. Strom, D. M. Stuver, A. Summerscales, T. Z. Sun, K-X Sung, M. Sutton, P. J. Takahashi, H. Tanner, D. B. Tarallo, M. Taylor, R. Taylor, R. Thacker, J. Thorne, K. A. Thorne, K. S. Thuering, A. Tinto, M. Tokmakov, K. V. Torres, C. Torrie, C. Traylor, G. Trias, M. Tyler, W. Ugolini, D. Ungarelli, C. Urbanek, K. Vahlbruch, H. Vallisneri, M. Van den Broeck, C. van Putten, M. Varvella, M. Vass, S. Vecchio, A. Veitch, J. Veitch, P. Villar, A. Vorvick, C. Vyachanin, S. P. Waldman, S. J. Wallace, L. Ward, H. Ward, R. Watts, K. Webber, D. Weidner, A. Weinert, M. Weinstein, A. Weiss, R. Wen, S. Wette, K. Whelan, J. T. Whitbeck, D. M. Whitcomb, S. E. Whiting, B. F. Wiley, S. Wilkinson, C. Willems, P. A. Williams, L. Willke, B. Wilmut, I. Winkler, W. Wipf, C. C. Wise, S. Wiseman, A. G. Woan, G. Woods, D. Wooley, R. Worden, J. Wu, W. Yakushin, I. Yamamoto, H. Yan, Z. Yoshida, S. Yunes, N. Zanolin, M. Zhang, J. Zhang, L. Zhao, C. Zotov, N. Zucker, M. zur Muehlen, H. Zweizig, J. CA AURIGA Collaboration LIGO Sci Collaboration TI A joint search for gravitational wave bursts with AURIGA and LIGO SO CLASSICAL AND QUANTUM GRAVITY LA English DT Article ID BLACK-HOLE COALESCENCES; SCIENCE RUN AB The first simultaneous operation of the AURIGA detector(63) and the LIGO observatory(64) was an opportunity to explore real data, joint analysis methods between two very different types of gravitational wave detectors: resonant bars and interferometers. This paper describes a coincident gravitational wave burst search, where data from the LIGO interferometers are cross-correlated at the time of AURIGA candidate events to identify coincident transients. The analysis pipeline is tuned with two thresholds, on the signal-to-noise ratio of AURIGA candidate events and on the significance of the cross-correlation test in LIGO. The false alarm rate is estimated by introducing time shifts between data sets and the network detection efficiency is measured by adding simulated gravitational wave signals to the detector output. The simulated waveforms have a significant fraction of power in the narrower AURIGA band. In the absence of a detection, we discuss how to set an upper limit on the rate of gravitational waves and to interpret it according to different source models. Due to the short amount of analyzed data and to the high rate of non-Gaussian transients in the detectors' noise at the time, the relevance of this study is methodological: this was the first joint search for gravitational wave bursts among detectors with such different spectral sensitivity and the first opportunity for the resonant and interferometric communities to unify languages and techniques in the pursuit of their common goal. C1 [Baggio, L.; Mezzena, R.; Mion, A.; Prodi, G. A.; Re, V.; Salemi, F.; Vitale, S.] Univ Trent, Dept Phys, I-38050 Trento, Italy. [Baggio, L.; Bonaldi, M.; Falferi, P.; Mezzena, R.; Mion, A.; Prodi, G. A.; Re, V.; Salemi, F.; Vinante, A.; Vitale, S.] Ist Nazl Fis Nucl, Grp Coll Trento, Padova Sect, I-38050 Trento, Italy. [Bignotto, M.; Cerdonio, M.; Fattori, S.; Liguori, N.] Univ Padua, Dept Phys, I-35131 Padua, Italy. [Bignotto, M.; Cerdonio, M.; Fattori, S.; Liguori, N.] Univ Padua, Ist Nazl Fis Nucl, Padova Sect, I-35131 Padua, Italy. [Bonaldi, M.; Falferi, P.; Vinante, A.] Univ Trent, Ist Foton & Nanotecnol, CNR, Fdn Bruno Kessler, I-38050 Trento, Italy. [De Rosa, M.; Inguscio, M.; Marin, F.] Ist Nazl Fis Nucl, Firenze Sect, I-50121 Florence, Italy. [De Rosa, M.] INOA, I-80078 Naples, Italy. [Fortini, P.] Univ Ferrara, Dept Phys, I-44100 Ferrara, Italy. [Fortini, P.] Ist Nazl Fis Nucl, Ferrara Sect, I-44100 Ferrara, Italy. [Giusfredi, G.] CNR, INOA, I-50125 Florence, Italy. [Inguscio, M.; Marin, F.] Univ Florence, Dept Phys, I-50121 Florence, Italy. [Inguscio, M.; Marin, F.] Univ Florence, LENS, I-50121 Florence, Italy. [Longo, S.; Ortolan, A.] Ist Nazl Fis Nucl, Lab Nazl Legnaro, I-35020 Legnaro, Padova, Italy. [Poggi, S.] Consorzio Criospazio Ric, I-38050 Trento, Italy. [Soranzo, G.; Taffarello, L.; Vedovato, G.; Zendri, J. P.] Ist Nazl Fis Nucl, Padova Sect, I-35100 Padua, Italy. [Abbott, B.; Abbott, R.; Adhikari, R.; Agresti, J.; Anderson, S. B.; Araya, M.; Armandula, H.; Ballmer, S.; Barish, B. C.; Bhawal, B.; Billingsley, G.; Black, E.; Blackburn, K.; Bork, R.; Boschi, V.; Brown, D. A.; Busby, D.; Cardenas, L.; Cepeda, C.; Chatterji, S.; Coyne, D.; Creighton, T. D.; D'Ambrosio, E.; DeSalvo, R.; Dietz, A.; Dupuis, R. J.; Ehrens, P.; Espinoza, E.; Etzel, T.; Evans, M.; Fairhurst, S.; Fazi, D.; Goggin, L. M.; Heefner, J.; Ivanov, A.; Kells, W.; Keppel, D. G.; King, P.; Kondrashov, V.; Kozak, D.; Lazzarini, A.; Lei, M.; Lindquist, P.; Mageswaran, M.; Mailand, K.; Mandic, V.; Maros, E.; Marx, J. N.; Meshkov, S.; Meyers, D.; Miyakawa, O.; Nocera, F.; Robertson, N. A.; Russell, P.; Samidi, M.; Sanders, G. H.; Sannibale, V.; Sears, B.; Sutton, P. J.; Taylor, R.; Tinto, M.; Tyler, W.; Varvella, M.; Vass, S.; Villar, A.; Waldman, S. J.; Wallace, L.; Ward, R.; Webber, D.; Weinstein, A.; Whitcomb, S. E.; Willems, P. A.; Yamamoto, H.; Zhang, L.; Zweizig, J.] CALTECH, LIGO, Pasadena, CA 91125 USA. [Ajith, P.; Allen, B.; Brinkmann, M.; Bunkowski, A.; Burmeister, O.; Cochrane, P.; Danzmann, K.; Harms, J.; Hewitson, M.; Lueck, H.; Somiya, K.; Weinert, M.; Willke, B.; Winkler, W.] Max Planck Inst Gravitat Phys, Albert Einstein Inst, D-30167 Hannover, Germany. [Allen, B.; Anderson, W. G.; Biswas, R.; Cannon, K.; Fotopoulos, N.; Hammer, D.; Itoh, Y.; Papa, M. A.; Ray-Majumder, S.; Wiseman, A. G.; Woods, D.] Univ Wisconsin, Milwaukee, WI 53201 USA. [Amin, R.; Hanna, C.; Kissel, J. S.; Rodriguez, A.; Wen, S.] Louisiana State Univ, Baton Rouge, LA 70803 USA. [Klimenko, S.; Mercer, R. A.; Mitselmakher, G.; Mueller, G.; Reitze, D. H.; Tanner, D. B.; Whiting, B. F.] Univ Florida, Gainesville, FL 32611 USA. [Ashley, M.; Dickson, J.; Gossler, S.; Gray, M.; McClelland, D. E.; McKenzie, K.; Moylan, A.; Rabeling, D.; Scott, S. M.; Searle, A. C.; Slagmolen, B. J. J.; Wette, K.] Australian Natl Univ, Canberra, ACT 0200, Australia. [Aston, S.; Cruise, A. M.; Freise, A.; Hoyland, D.; Kasprzyk, D.; Ungarelli, C.] Univ Birmingham, Birmingham B15 2TT, W Midlands, England. [Aufmuth, P.; Danzmann, K.; Franzen, A.; Hild, S.; Meier, T.; Vahlbruch, H.; Willke, B.] Leibnitz Univ Hannover, D-30167 Hannover, Germany. [Aulbert, C.; Babak, S.; Whelan, J. T.] Max Planck Inst Gravitat Phys, Albert Einstein Inst, D-14476 Golm, Germany. [Bantilan, H.; Christensen, N.] Carleton Coll, Northfield, MN 55057 USA. [Barker, C.; Barker, D.; Cook, D.; Garofoli, J.; Guenther, M.; Kawabe, K.; McCarthy, R.; Myers, E.; Myers, J.; Radkins, H.; Rivera, B.; Ryan, K.; Sandberg, V.; Schwinberg, P.; Sigg, D.; Vorvick, C.; Wilkinson, C.] LIGO Hanford Observ, Richland, WA 99352 USA. [Barr, B.; Bogenstahl, J.; Cantley, C. A.; Casey, M. M.; Chalkley, E.; Clark, J.; Cumming, A.; Grant, A.; Heng, I. S.; Heptonstall, A.; Huttner, S. H.; Jones, R.; Martin, I.; Murray, P.; Plissi, M. V.; Strain, K. A.; Taylor, R.; Tokmakov, K. V.; Torrie, C.; Ward, H.; Woan, G.] Univ Glasgow, Glasgow G12 8QQ, Lanark, Scotland. [Barriga, P.; Blair, D.; Coward, D.; Fan, Y.; Lee, B.; Schediwy, S.; Yan, Z.] Univ Western Australia, Crawley, WA 6009, Australia. [Bayer, K.; Betzwieser, J.; Corbitt, T.; Fritschel, P.; Katsavounidis, E.; MacInnis, M.; Mavalvala, N.; Ottaway, D. J.; Shoemaker, D. H.; van Putten, M.; Weiss, R.; Wipf, C. C.; Zanolin, M.] MIT, LIGO, Cambridge, MA 02139 USA. [Belczynski, K.; Kalogera, V.; Kim, C.; O'Shaughnessy, R.] Northwestern Univ, Evanston, IL 60208 USA. [Beyersdorf, P. T.] San Jose State Univ, San Jose, CA 95192 USA. [Bilenko, I. A.; Khalili, F. Ya; Mitrofanov, V. P.; Vyachanin, S. P.] Moscow MV Lomonosov State Univ, Moscow 119992, Russia. [Bogue, L.; Giaime, J. A.; Giardina, K. D.; Hanson, J.; Lormand, M.; Parameswariah, C.; Roddy, S.; Sibley, A.; Yakushin, I.] LIGO Livingston Observ, Livingston, LA 70754 USA. [Bose, S.; Leiner, J.] Washington State Univ, Pullman, WA 99164 USA. [Brau, J. E.; Ito, M.; Rahkola, R.] Univ Oregon, Eugene, OR 97403 USA. [Brooks, A.; Mudge, D.; Munch, J.] Univ Adelaide, Adelaide, SA 5005, Australia. [Savov, P.; Siemens, X.; Thorne, K. S.; Vallisneri, M.] CALTECH, CaRT, Pasadena, CA 91125 USA. [Bullington, A.; Degree, M.; Fejer, M. M.; Lantz, B.; Route, R.; Sinha, S.; Sun, K-X; Urbanek, K.] Stanford Univ, Stanford, CA 94305 USA. [Shawhan, P.] Univ Maryland, College Pk, MD 20742 USA. [Butler, W. E.; Fricke, T.; Giampanis, S.; Melissinos, A.] Univ Rochester, Rochester, NY 14627 USA. [Camp, J. B.; Cannizzo, J.; McWilliams, S.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Demma, T.] Univ Sannio Benevento, I-82100 Benevento, Italy. [Charlton, P.; O'Reilly, B.] Charles Sturt Univ, Wagga Wagga, NSW 2678, Australia. [Chiadini, F.; Fiumara, V.; Longo, M.; Postiglione, F.] Univ Salerno, I-84084 Salerno, Italy. [Chin, D.; Dergachev, V.; Gustafson, R.; Riles, K.] Univ Michigan, Ann Arbor, MI 48109 USA. [Davies, G.; Van den Broeck, C.] Cardiff Univ, Cardiff CF24 3AA, Wales. [Dalrymple, J.] Syracuse Univ, Syracuse, NY 13244 USA. [Desai, S.; Rakhmanov, M.; Ramsunder, M.; Whitbeck, D. M.] Penn State Univ, University Pk, PA 16802 USA. [Dhurandhar, S.; Mitra, S.] Inter Univ, Ctr Astron & Astrophys, Pune 411007, Maharashtra, India. [Diaz, M.; Mohanty, S.] Univ Texas Brownsville & Texas Southmost Coll, Brownsville, TX 78520 USA. [Doomes, E. E.; McGuire, S. C.] Southern Univ, Baton Rouge, LA 70813 USA. [Doomes, E. E.; McGuire, S. C.] A&M Coll, Baton Rouge, LA 70813 USA. [Marka, S.] Columbia Univ, New York, NY 10027 USA. [Ganezer, K. S.; Wiley, S.] Calif State Univ Dominguez Hills, Carson, CA 90747 USA. [Greenhalgh, J.; Hayler, T.; Wilmut, I.] Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. [Gretarsson, A. M.] Embry Riddle Aeronaut Univ, Prescott, AZ 86301 USA. [Jones, D. I.] Univ Southampton, Southampton SO17 1BJ, Hants, England. [Kawazoe, F.; Kokeyama, K.; Leonhardt, V.; Sakata, S.] Natl Inst Nat Sci, Natl Astron Observ Japan, Mitaka, Tokyo 1818588, Japan. [Lockerbie, N. A.] Univ Strathclyde, Glasgow G1 1XQ, Lanark, Scotland. [McHugh, M.] Loyola Univ, New Orleans, LA 70118 USA. [de la Jordana, L. Sancho; Sintes, A. M.] Univ Illes Balears, E-07122 Palma de Mallorca, Spain. [Saraf, S.] Rochester Inst Technol, Rochester, NY 14623 USA. [Summerscales, T. Z.] Andrews Univ, Berrien Springs, MI 49104 USA. [Ugolini, D.] Trinity Univ, San Antonio, TX 78212 USA. [Yoshida, S.] SE Louisiana Univ, Hammond, LA 70402 USA. [Zotov, N.] Louisiana Tech Univ, Ruston, LA 71272 USA. Hobart & William Smith Coll, Geneva, NY 14456 USA. RP Baggio, L (reprint author), Univ Trent, Dept Phys, I-38050 Trento, Italy. RI Vitale, Stefano/C-2312-2012; Ottaway, David/J-5908-2015; Mezzena, Renato/K-1802-2015; Postiglione, Fabio/O-4744-2015; Howell, Eric/H-5072-2014; Biswas, Rahul/H-7474-2016; Tarallo, Marco/B-2096-2012; Sigg, Daniel/I-4308-2015; Pinto, Innocenzo/L-3520-2016; Harms, Jan/J-4359-2012; Chow, Jong/A-3183-2008; Frey, Raymond/E-2830-2016; Ju, Li/C-2623-2013; Re, Virginia /F-6403-2013; Pitkin, Matthew/I-3802-2013; Giusfredi, Giovanni/I-6961-2013; Marin, Francesco/I-7492-2013; Vyatchanin, Sergey/J-2238-2012; van Putten, Maurice/F-5237-2011; Salemi, Francesco/F-6988-2014; Khalili, Farit/D-8113-2012; Chiadini, Francesco/E-1812-2015; Falferi, Paolo/C-3439-2015; Vecchio, Alberto/F-8310-2015; Mow-Lowry, Conor/F-8843-2015; Kawazoe, Fumiko/F-7700-2011; Freise, Andreas/F-8892-2011; Kawabe, Keita/G-9840-2011; prodi, giovanni/B-4398-2010; Finn, Lee Samuel/A-3452-2009; Agresti, Juri/G-8168-2012; De Rosa, Maurizio/C-5069-2009; Mitrofanov, Valery/D-8501-2012; Bilenko, Igor/D-5172-2012; Allen, Bruce/K-2327-2012; Chen, Yanbei/A-2604-2013; Barker, David/A-5671-2013; Zhao, Chunnong/C-2403-2013; Ward, Robert/I-8032-2014; Schutz, Bernard/B-1504-2010; Casey, Morag/C-9703-2010; Rowan, Sheila/E-3032-2010; Strain, Kenneth/D-5236-2011; Raab, Frederick/E-2222-2011; Lueck, Harald/F-7100-2011; Lam, Ping Koy/A-5276-2008; Galdi, Vincenzo/B-1670-2008; Bonaldi, Michele/C-5127-2008; Vinante, Andrea/A-1562-2009; McClelland, David/E-6765-2010; Martin, Iain/A-2445-2010; Hild, Stefan/A-3864-2010 OI Vitale, Stefano/0000-0002-2427-8918; Mezzena, Renato/0000-0001-9891-0472; Postiglione, Fabio/0000-0003-0628-3796; Howell, Eric/0000-0001-7891-2817; Biswas, Rahul/0000-0002-0774-8906; Tarallo, Marco/0000-0001-5169-4987; Sigg, Daniel/0000-0003-4606-6526; Chow, Jong/0000-0002-2414-5402; Frey, Raymond/0000-0003-0341-2636; Pitkin, Matthew/0000-0003-4548-526X; Marin, Francesco/0000-0001-8227-124X; Chiadini, Francesco/0000-0002-9339-8622; Falferi, Paolo/0000-0002-1929-4710; Vecchio, Alberto/0000-0002-6254-1617; prodi, giovanni/0000-0001-5256-915X; Finn, Lee Samuel/0000-0002-3937-0688; Agresti, Juri/0000-0001-6119-2470; De Rosa, Maurizio/0000-0002-5542-6733; Allen, Bruce/0000-0003-4285-6256; Zhao, Chunnong/0000-0001-5825-2401; Pinto, Innocenzo M./0000-0002-2679-4457; Pierro, Vincenzo/0000-0002-6020-5521; Nishizawa, Atsushi/0000-0003-3562-0990; Zweizig, John/0000-0002-1521-3397; O'Shaughnessy, Richard/0000-0001-5832-8517; Ward, Robert/0000-0001-5503-5241; Whelan, John/0000-0001-5710-6576; Vedovato, Gabriele/0000-0001-7226-1320; LONGO, Maurizio/0000-0001-8325-4003; Fairhurst, Stephen/0000-0001-8480-1961; Boschi, Valerio/0000-0001-8665-2293; Aulbert, Carsten/0000-0002-1481-8319; Freise, Andreas/0000-0001-6586-9901; MATTA, VINCENZO/0000-0002-2046-4027; MARANO, Stefano/0000-0002-5307-0980; Whiting, Bernard F/0000-0002-8501-8669; Veitch, John/0000-0002-6508-0713; Papa, M.Alessandra/0000-0002-1007-5298; Strain, Kenneth/0000-0002-2066-5355; Lueck, Harald/0000-0001-9350-4846; Lam, Ping Koy/0000-0002-4421-601X; Galdi, Vincenzo/0000-0002-4796-3600; Bonaldi, Michele/0000-0001-7996-3544; Vinante, Andrea/0000-0002-9385-2127; McClelland, David/0000-0001-6210-5842; NR 27 TC 14 Z9 14 U1 2 U2 15 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0264-9381 J9 CLASSICAL QUANT GRAV JI Class. Quantum Gravity PD MAY 7 PY 2008 VL 25 IS 9 AR 095004 DI 10.1088/0264-9381/25/9/095004 PG 16 WC Astronomy & Astrophysics; Physics, Multidisciplinary; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 301LF UT WOS:000255897000005 ER PT J AU Mazarico, E Zuber, MT Lemoine, FG Smith, DE AF Mazarico, E. Zuber, M. T. Lemoine, F. G. Smith, D. E. TI Observation of atmospheric tides in the Martian exosphere using Mars Reconnaissance Orbiter radio tracking data SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID TERRESTRIAL PLANET THERMOSPHERES; SOLAR-CYCLE VARIATION; GLOBAL SURVEYOR; MGS ACCELEROMETER; THERMAL TIDES; DENSITY AB Based on the perturbations of the trajectory of the Mars Reconnaissance Orbiter due to atmospheric drag, we estimate, using Precision Orbit Determination, the density of the Martian exosphere near 250 km altitude with much better temporal (and therefore spatial) resolution than previously possible with this method. Small longitudinal density variations are observed to be consistent over long time periods. Although they appear fixed with respect to the planet, we interpret them as non-migrating tides because of the Sun-synchronous spacecraft orbit. Similar tides were observed previously by MGS at much lower altitude (similar to 125 km), and our results agree to first order with the MGS findings. C1 [Mazarico, E.; Zuber, M. T.] MIT, Dept Earth Atmospher & Planetary Sci, Cambridge, MA 02139 USA. [Zuber, M. T.; Lemoine, F. G.; Smith, D. E.] NASA, Goddard Space Flight Ctr, Solar Syst Explorat Div, Greenbelt, MD 20771 USA. RP Mazarico, E (reprint author), MIT, Dept Earth Atmospher & Planetary Sci, 77 Massachusetts Ave, Cambridge, MA 02139 USA. EM mazarico@alum.mit.edu RI Lemoine, Frank/D-1215-2013; Mazarico, Erwan/N-6034-2014 OI Mazarico, Erwan/0000-0003-3456-427X NR 19 TC 7 Z9 7 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 EI 1944-8007 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAY 7 PY 2008 VL 35 IS 9 AR L09202 DI 10.1029/2008GL033388 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 300LI UT WOS:000255824900002 ER PT J AU Sibeck, DG Kuznetsova, M Angelopoulos, V Glassmeier, KH McFadden, JP AF Sibeck, D. G. Kuznetsova, M. Angelopoulos, V. Glassmeier, K. -H. McFadden, J. P. TI Crater FTEs: Simulation results and THEMIS observations SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID FLUX-TRANSFER EVENTS; DAYSIDE MAGNETOPAUSE; RECONNECTION; WAVES AB The BATS-R-US magnetohydrodynamic (MHD) model predicts flux transfer events (FTEs) with strong core magnetic fields embedded within a broadened current layer of weak magnetic field strengths on the equatorial dayside magnetopause during intervals of southward and duskward interplanetary magnetic field (IMF) orientation. Multipoint THEMIS observations at 2202 UT on June 20, 2007 of a southward-moving FTE on the post-noon magnetopause confirm the predictions of the model. THEMIS-E and -A with large impact parameters simply observe enhanced magnetic field strengths in draped magnetosheath magnetic field lines, THEMIS-B and -C with moderate impact parameters pass through the broadened current layer to observe crater FTEs with deep troughs bounding a strong core field, while THEMIS-D with a very low impact parameter observes the core magnetic field strength enhancement embedded in the current layer. C1 [Sibeck, D. G.; Kuznetsova, M.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Angelopoulos, V.] Univ Calif Los Angeles, IGPP, Los Angeles, CA 90095 USA. [McFadden, J. P.] UCB, SSL, Berkeley, CA 94720 USA. [Glassmeier, K. -H.] Tech Univ Carolo Wilhelmina Braunschweig, D-38106 Braunschweig, Germany. RP Sibeck, DG (reprint author), NASA, Goddard Space Flight Ctr, Code 674, Greenbelt, MD 20771 USA. EM david.g.sibeck@nasa.gov RI Sibeck, David/D-4424-2012; Kuznetsova, Maria/F-6840-2012 NR 13 TC 25 Z9 25 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAY 7 PY 2008 VL 35 IS 17 AR L17S06 DI 10.1029/2008GL033568 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 300LR UT WOS:000255825800002 ER PT J AU Celarier, EA Brinksma, EJ Gleason, JF Veefkind, JP Cede, A Herman, JR Ionov, D Goutail, F Pommereau, JP Lambert, JC van Roozendael, M Pinardi, G Wittrock, F Schonhardt, A Richter, A Ibrahim, OW Wagner, T Bojkov, B Mount, G Spinei, E Chen, CM Pongetti, TJ Sander, SP Bucsela, EJ Wenig, MO Swart, DPJ Volten, H Kroon, M Levelt, PF AF Celarier, E. A. Brinksma, E. J. Gleason, J. F. Veefkind, J. P. Cede, A. Herman, J. R. Ionov, D. Goutail, F. Pommereau, J. -P. Lambert, J. -C. van Roozendael, M. Pinardi, G. Wittrock, F. Schoenhardt, A. Richter, A. Ibrahim, O. W. Wagner, T. Bojkov, B. Mount, G. Spinei, E. Chen, C. M. Pongetti, T. J. Sander, S. P. Bucsela, E. J. Wenig, M. O. Swart, D. P. J. Volten, H. Kroon, M. Levelt, P. F. TI Validation of ozone monitoring instrument nitrogen dioxide columns SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID INDUCED FLUORESCENCE DETECTION; ABSORPTION CROSS-SECTIONS; RADIATIVE-TRANSFER; ATMOSPHERIC NO2; GOME; NM; RETRIEVAL; MODEL; SPECTROSCOPY; TEMPERATURE AB We review the standard nitrogen dioxide (NO2) data product (Version 1.0.), which is based on measurements made in the spectral region 415-465 nm by the Ozone Monitoring Instrument (OMI) on the NASA Earth Observing System-Aura satellite. A number of ground- and aircraft-based measurements have been used to validate the data product's three principal quantities: stratospheric, tropospheric, and total NO2 column densities under nearly or completely cloud-free conditions. The validation of OMI NO2 is complicated by a number of factors, the greatest of which is that the OMI observations effectively average the NO2 over its field of view (minimum 340 km 2), while a ground- based instrument samples at a single point. The tropospheric NO2 field is often very inhomogeneous, varying significantly over tens to hundreds of meters, and ranges from <10(15) cm(-2) over remote, rural areas to >10(16) cm(-2) over urban and industrial areas. Because of OMI's areal averaging, when validation measurements are made near NO2 sources the OMI measurements are expected to underestimate the ground- based, and this is indeed seen. Further, we use several different instruments, both new and mature, which might give inconsistent NO2 amounts; the correlations between nearby instruments is 0.8-0.9. Finally, many of the validation data sets are quite small and span a very short length of time; this limits the statistical conclusions that can be drawn from them. Despite these factors, good agreement is generally seen between the OMI and ground- based measurements, with OMI stratospheric NO2 underestimated by about 14% and total and tropospheric columns underestimated by 15-30%. Typical correlations between OMI NO2 and ground- based measurements are generally >0.6. C1 [Celarier, E. A.] SGT Inc, Greenbelt, MD 20770 USA. [Brinksma, E. J.; Veefkind, J. P.; Volten, H.; Kroon, M.; Levelt, P. F.] Royal Netherlands Meteorol Inst, NL-3730 AE De Bilt, Netherlands. [Gleason, J. F.; Herman, J. R.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Cede, A.; Bojkov, B.; Bucsela, E. J.; Wenig, M. O.] Univ Maryland Baltimore Cty, GEST Program, Baltimore, MD 21250 USA. [Ionov, D.] St Petersburg State Univ, Phys Res Inst, Dept Atmospher Phys, St Petersburg 198904, Russia. [Ionov, D.; Goutail, F.; Pommereau, J. -P.] CNRS, F-91370 Verrieres Le Buisson, France. [Lambert, J. -C.; van Roozendael, M.; Pinardi, G.] Belgian Inst Space Aeron, B-1180 Brussels, Belgium. [Wittrock, F.; Schoenhardt, A.; Richter, A.] Univ Bremen, Inst Environm Phys, D-28334 Bremen, Germany. [Ibrahim, O. W.] Heidelberg Univ, Inst Environm Phys, D-69120 Heidelberg, Germany. [Wagner, T.] Max Planck Inst Chem, D-55128 Mainz, Germany. [Mount, G.; Spinei, E.] Washington State Univ, Dept Civil & Environm Engn, Lab Atmospher Res, Pullman, WA 99164 USA. [Chen, C. M.; Pongetti, T. J.; Sander, S. P.] CALTECH, Jet Prop Lab, NASA, Div Sci, Pasadena, CA 91109 USA. [Swart, D. P. J.; Volten, H.] Natl Inst Publ Hlth & Environm, NL-3720 BA Bilthoven, Netherlands. RP Celarier, EA (reprint author), SGT Inc, 7701 Greenbelt Rd, Greenbelt, MD 20770 USA. RI Wittrock, Folkard/B-6959-2008; Richter, Andreas/C-4971-2008; Gleason, James/E-1421-2012; Wenig, Mark/K-7279-2012; Ionov, Dmitry/J-4461-2013; OI Wittrock, Folkard/0000-0002-3024-0211; Richter, Andreas/0000-0003-3339-212X; Ionov, Dmitry/0000-0002-4844-5397; Herman, Jay/0000-0002-9146-1632 NR 46 TC 96 Z9 97 U1 3 U2 20 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 7 PY 2008 VL 113 IS D15 AR D15S15 DI 10.1029/2007JD008908 PG 23 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 300MI UT WOS:000255827500003 ER PT J AU Kim, MJ Weinman, JA Olson, WS Chang, DE Skofronick-Jackson, G Wang, JR AF Kim, Min-Jeong Weinman, J. A. Olson, W. S. Chang, D. -E. Skofronick-Jackson, G. Wang, J. R. TI A physical model to estimate snowfall over land using AMSU-B observations SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID MICROPHYSICAL PROPERTY RETRIEVALS; MICROWAVE SOUNDING UNIT; RADIATIVE-TRANSFER; PRECIPITATION RETRIEVAL; MILLIMETER WAVELENGTHS; SIZE DISTRIBUTIONS; SURFACE EMISSIVITY; POLARIMETRIC RADAR; SINGLE-SCATTERING; ICE PARTICLE AB In this study, we present a physical model to retrieve snowfall rate over land using brightness temperature observations from NOAA's Advanced Microwave Sounder Unit-B (AMSU-B) at 89 GHz, 150 GHz, 183.3 +/- 1 GHz, 183.3 +/- 3 GHz, and 183.3 +/- 7 GHz. The retrieval model is applied to the New England blizzard of 5 March 2001 which deposited about 75 cm of snow over much of Vermont, New Hampshire, and northern New York. In this physical model, prior retrieval assumptions about snowflake shape, particle size distributions, environmental conditions, and optimization methodology have been updated. Here, single scattering parameters for snow particles are calculated with the discrete-dipole approximation (DDA) method instead of assuming spherical shapes. Five different snow particle models are considered. Snow particle size distributions are assumed to vary with air temperature and to follow aircraft measurements described by previous studies. Brightness temperatures at AMSU-B frequencies for the New England blizzard are calculated using these DDA calculated single scattering parameters and particle size distributions. The vertical profiles of pressure, temperature, relative humidity and hydrometeors are provided by MM5 model simulations. These profiles are treated as the a priori database in the Bayesian retrieval algorithm. In algorithm applications to the blizzard data, calculated brightness temperatures associated with selected database profiles agree with AMSU-B observations to within about +/- 5 K at all five frequencies. Retrieved snowfall rates compare favorably with the near-concurrent National Weather Service (NWS) radar reflectivity measurements. The relationships between the NWS radar measured reflectivities Z(e) and retrieved snowfall rate R for a given snow particle model are derived by a histogram matching technique. All of these Z(e)-R relationships fall in the range of previously established Z(e)-R relationships for snowfall. This suggests that the current physical model developed in this study can reliably estimate the snowfall rate over land using the AMSU-B measured brightness temperatures. C1 [Kim, Min-Jeong] NOAA, NESDIS, Ctr Satellite Applicat & Res, Camp Springs, MD 20746 USA. [Kim, Min-Jeong] Colorado State Univ, Cooperat Inst Res Atmospher Sci, Ft Collins, CO 80523 USA. [Weinman, J. A.] Univ Washington, Dept Atmospher Sci, Seattle, WA 98195 USA. [Olson, W. S.] Univ Maryland Baltimore Cty, Joint Ctr Earth Syst Technol, Baltimore, MD 21228 USA. [Olson, W. S.; Skofronick-Jackson, G.; Wang, J. R.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Chang, D. -E.] Meteorol Res Inst, Forecast Res Lab, Seoul 156720, South Korea. RP Kim, MJ (reprint author), NOAA, NESDIS, Ctr Satellite Applicat & Res, Room 712,5200 Auth Rd, Camp Springs, MD 20746 USA. EM min-jeong.kim@noaa.gov RI Skofronick-Jackson, Gail/D-5354-2012 NR 51 TC 23 Z9 24 U1 0 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 7 PY 2008 VL 113 IS D9 AR D09201 DI 10.1029/2007JD008589 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 300MD UT WOS:000255827000001 ER PT J AU Nassar, R Logan, JA Worden, HM Megretskaia, IA Bowman, KW Osterman, GB Thompson, AM Tarasick, DW Austin, S Claude, H Dubey, MK Hocking, WK Johnson, BJ Joseph, E Merrill, J Morris, GA Newchurch, M Oltmans, SJ Posny, F Schmidlin, FJ Vomel, H Whiteman, DN Witte, JC AF Nassar, Ray Logan, Jennifer A. Worden, Helen M. Megretskaia, Inna A. Bowman, Kevin W. Osterman, Gregory B. Thompson, Anne M. Tarasick, David W. Austin, Shermane Claude, Hans Dubey, Manvendra K. Hocking, Wayne K. Johnson, Bryan J. Joseph, Everette Merrill, John Morris, Gary A. Newchurch, Mike Oltmans, Samuel J. Posny, Francoise Schmidlin, F. J. Voemel, Holger Whiteman, David N. Witte, Jacquelyn C. TI Validation of Tropospheric Emission Spectrometer (TES) nadir ozone profiles using ozonesonde measurements SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID MAPPING SPECTROMETER; CLIMATOLOGY; VARIABILITY; SATELLITE; MODEL; TOMS AB We compare Tropospheric Emission Spectrometer (TES) version 2 (V002) nadir ozone profiles with ozonesonde profiles from the Intercontinental Chemical Transport Experiment Ozonesonde Network Study, the World Ozone and Ultraviolet Data Center, the Global Monitoring Division of the Earth System Research Laboratory, and the Southern Hemisphere Additional Ozonesonde archives. Approximately 1600 coincidences spanning 72.5 degrees S - 80.3 degrees N from October 2004 to October 2006 are found. The TES averaging kernel and constraint are applied to the ozonesonde data to account for the TES measurement sensitivity and vertical resolution. TES sonde differences are examined in six latitude zones after excluding profiles with thick high clouds. Values for the bias and standard deviation are determined using correlations of mean values of TES ozone and sonde ozone in the upper troposphere (UT) and lower troposphere (LT). The UT biases range from 2.9 to 10.6 ppbv, and the LT biases range from 3.7 to 9.2 ppbv, excluding the Arctic and Antarctic LT where TES sensitivity is low. A similar approach is used to assess seasonal differences in the northern midlatitudes where the density and frequency of sonde measurements are greatest. These results are briefly compared to TES V001 ozone validation work which also used ozonesondes but was carried out prior to improvements in the radiometric calibration and ozone retrieval in V002. Overall, the large number of TES and sonde comparisons indicate a positive bias of approximately 3 - 10 ppbv for the TES V002 nadir ozone data set and have helped to identify areas of potential improvement for future retrieval versions. C1 [Nassar, Ray; Logan, Jennifer A.; Megretskaia, Inna A.] Harvard Univ, Sch Engn & Appl Sci, Cambridge, MA 02138 USA. [Austin, Shermane] CUNY Medgar Evers Coll, Brooklyn, NY 11225 USA. [Bowman, Kevin W.; Osterman, Gregory B.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Claude, Hans] Deutsch Wetterdienst Meteorol Observ, D-82383 Hohenpeissenberg, Germany. [Dubey, Manvendra K.] Los Alamos Natl Lab, Los Alamos, NM 87545 USA. [Hocking, Wayne K.] Univ Western Ontario, Dept Phys & Astron, London, ON N6A 3K7, Canada. [Johnson, Bryan J.; Oltmans, Samuel J.] NOAA, Earth Syst Res Lab, Boulder, CO 80305 USA. [Tarasick, David W.] Environm Canada, Expt Studies, Air Qual Res Div, Downsview, ON, Canada. [Thompson, Anne M.] Penn State Univ, Dept Meteorol, University Pk, PA 16802 USA. [Worden, Helen M.] Natl Ctr Atmospher Res, Div Atmospher Chem, Boulder, CO 80305 USA. RP Nassar, R (reprint author), Harvard Univ, Sch Engn & Appl Sci, Pierce Hall,29 Oxford St, Cambridge, MA 02138 USA. EM ray@io.as.harvard.edu; jal@io.harvard.edu; hmw@ucar.edu; iam@io.harvard.edu; kevin.bowman@jpl.nasa.gov; gregory.b.osterman@jpl.nasa.gov; anne@met.psu.edu; david.n.whiteman@nasa.gov; saustin@mec.cuny.edu; hans.claude@dwd.de; dubey@lanl.gov; whocking@uwo.ca; bryan.johnson@noaa.gov; ejoseph@howard.edu; jmerrill@gso.uri.edu; gary.morris@valpo.edu; mike@nsstc.uah.edu; samuel.j.oltmans@noaa.gov; francoise.posny@univ-reunion.fr; fjs@osb1.wff.nasa.gov; holger.voemel@colorado.edu; david.tarasick@ec.gc.ca; witte@gavial.gsfc.nasa.gov RI Dubey, Manvendra/E-3949-2010; Thompson, Anne /C-3649-2014; OI Dubey, Manvendra/0000-0002-3492-790X; Thompson, Anne /0000-0002-7829-0920; Nassar, Ray/0000-0001-6282-1611; Tarasick, David/0000-0001-9869-0692 NR 37 TC 107 Z9 108 U1 3 U2 15 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 7 PY 2008 VL 113 IS D15 AR D15S17 DI 10.1029/2007JD008819 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 300MI UT WOS:000255827500002 ER PT J AU Osterman, GB Kulawik, SS Worden, HM Richards, NAD Fisher, BM Eldering, A Shephard, MW Froidevaux, L Labow, G Luo, M Herman, RL Bowman, KW Thompson, AM AF Osterman, G. B. Kulawik, S. S. Worden, H. M. Richards, N. A. D. Fisher, B. M. Eldering, A. Shephard, M. W. Froidevaux, L. Labow, G. Luo, M. Herman, R. L. Bowman, K. W. Thompson, A. M. TI Validation of Tropospheric Emission Spectrometer (TES) measurements of the total, stratospheric, and tropospheric column abundance of ozone SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID MONITORING INSTRUMENT; AURA SATELLITE; OBJECTIVES AB The Tropospheric Emission Spectrometer (TES) is an infrared, high-resolution Fourier transform spectrometer which was launched onboard NASA's Aura satellite in 2004 and is providing global, vertically resolved measurements of ozone in the troposphere. TES version 2 (V002) data profiles have been validated in the troposphere and lower stratosphere by way of comparison to ozonesondes and aircraft measurements. TES measurements also have sensitivity throughout the stratosphere, and therefore TES ozone profiles can be integrated to determine the total and stratospheric column in addition to the tropospheric column ozone values. In this work we compare the ozone in the stratosphere measured by TES to observations from the Microwave Limb Sounder (MLS) instrument in order to show the quality of the TES measurements in the stratosphere. We also compare the determination of a total column value for ozone based on the TES profiles to the column measured by the Ozone Monitoring Instrument (OMI). The TES tropospheric ozone column value is also calculated from the TES profiles and compared with column values determined from ozonesonde data. Column measurements are useful because the errors are markedly reduced from errors at the profile levels and can be used to assess both biases and quality of the TES ozone retrievals. TES observations of total or partial column ozone compare well with the other instruments but tend toward higher values than the other measurements. Specifically, TES is higher than OMI by similar to 10 Dobson units (DU) for the total ozone column. TES measures higher values in the stratosphere (above 100 hPa) by similar to 3 DU and measures higher ozone column values (similar to 4 DU) in the troposphere than ozonesondes. While the strength of the TES nadir ozone product is the vertical resolution it provides in the troposphere, a tropospheric column value derived from TES have utility in analyses using or validating tropospheric ozone residual products. C1 [Osterman, G. B.; Kulawik, S. S.; Worden, H. M.; Richards, N. A. D.; Fisher, B. M.; Eldering, A.; Froidevaux, L.; Luo, M.; Herman, R. L.; Bowman, K. W.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Labow, G.] NASA, Goddard Space Flight Ctr, Raytheon Tech Serv Co, Greenbelt, MD 20771 USA. [Shephard, M. W.] Atmospher & Environm Res Inc, Lexington, MA 02421 USA. [Thompson, A. M.] Penn State Univ, Dept Meteorol, University Pk, PA 16802 USA. RP Osterman, GB (reprint author), CALTECH, Jet Prop Lab, MS 183-601,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM gregory.osterman@jpl.nasa.gov RI Herman, Robert/H-9389-2012; Thompson, Anne /C-3649-2014 OI Herman, Robert/0000-0001-7063-6424; Thompson, Anne /0000-0002-7829-0920 NR 29 TC 46 Z9 46 U1 0 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 7 PY 2008 VL 113 IS D15 AR D15S16 DI 10.1029/2007JD008801 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 300MI UT WOS:000255827500001 ER PT J AU Ribaya, BP Leung, J Brown, P Rahman, M Nguyen, CV AF Ribaya, Bryan P. Leung, Joseph Brown, Philip Rahman, Mahmud Nguyen, Cattien V. TI A study on the mechanical and electrical reliability of individual carbon nanotube field emission cathodes SO NANOTECHNOLOGY LA English DT Article ID SCANNING PROBE MICROSCOPY; FABRICATION; BEAM; TIPS; MICROCATHODES; EMITTER AB Individual carbon nanotube (CNT) field emission characteristics present a number of advantages for potential applications in electron microscopy and electron beam lithography. Mechanical and electrical reliability of individual CNT cathodes, however, remains a challenge and thus device integration of these cathodes has been limited. In this work, we present an investigation into the reliability issues concerning individual CNT field emission cathodes. We also introduce and analyze the reliability of a novel individual CNT cathode. The cathode structure is composed of a multi-walled carbon nanotube (MWNT) attached by Joule heating to a nickel-coated Si microstructure. The junction of the CNT and the Si microstructure is mechanically and electrically robust to withstand the strong electric field conditions that are typical for field emission devices. An optimal Ni film coating of 25 nm on the Si microstructure is required for mechanical and electrical stability. Experimental current-voltage data for the new cathode structure definitively demonstrates carbon nanotube field emission. Additionally, we demonstrate that our new nanofabrication method is capable of producing sophisticated cathode structures that were previously not realizable, such as one consisting of two parallel MWNTs, with highly controlled CNT lengths with 40 nm accuracy and nanotube-to-nanotube separations of less than 10 mu m. C1 [Ribaya, Bryan P.; Leung, Joseph; Brown, Philip; Nguyen, Cattien V.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. [Ribaya, Bryan P.; Rahman, Mahmud; Nguyen, Cattien V.] Santa Clara Univ, Elect Dev Lab, Santa Clara, CA 95053 USA. RP Nguyen, CV (reprint author), NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. EM V.Nguyen@nasa.gov NR 41 TC 20 Z9 20 U1 1 U2 10 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0957-4484 J9 NANOTECHNOLOGY JI Nanotechnology PD MAY 7 PY 2008 VL 19 IS 18 AR 185201 DI 10.1088/0957-4484/19/18/185201 PG 8 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied SC Science & Technology - Other Topics; Materials Science; Physics GA 290BM UT WOS:000255097700003 PM 21825685 ER PT J AU Bell, TL Rosenfeld, D AF Bell, Thomas L. Rosenfeld, Daniel TI Comment on "Weekly precipitation cycles? Lack of evidence from United States surface stations'' by D. M. Schultz et al. SO GEOPHYSICAL RESEARCH LETTERS LA English DT Editorial Material AB Schultz et al. (2007) (hereinafter referred to as S07) recently published the results of their search for a weekly cycle in U. S. rain-gauge measurements, claiming that their null results contradict those of a study (unpublished at the time) by Bell et al. (2008) (hereinafter referred to as B08) of satellite and rain-gauge data. S07 failed to note 1) that the satellite results described by B08 were for the years 1998 and after, whereas their data ended in 1992, and 2) that the analysis by B08 of rain- gauge data for the years studied by S07 were consistent with their conclusions. B08 in fact show that the weekly cycle in rainfall over the SE U. S. becomes detectable after about 1990. We discuss the methods used by S07. We suggest that a more focused approach-if guided by physical theory-can extract far more useful information from a dataset than generic statistical searches such as described by S07. C1 [Bell, Thomas L.] NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. [Rosenfeld, Daniel] Hebrew Univ Jerusalem, Inst Earth Sci, IL-91904 Jerusalem, Israel. RP Bell, TL (reprint author), NASA, Goddard Space Flight Ctr, Atmospheres Lab, Mail Code 613-2, Greenbelt, MD 20771 USA. EM thomas.l.bell@nasa.gov; daniel@vms.huji.ac.il RI Bell, Thomas/G-5425-2012; Rosenfeld, Daniel/F-6077-2016 OI Rosenfeld, Daniel/0000-0002-0784-7656 NR 9 TC 16 Z9 16 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAY 6 PY 2008 VL 35 IS 9 AR L09803 DI 10.1029/2007GL033046 PG 3 WC Geosciences, Multidisciplinary SC Geology GA 300LG UT WOS:000255824700001 ER PT J AU Li, ZJ Chao, Y McWilliams, JC Ide, K AF Li, Zhijin Chao, Yi McWilliams, James C. Ide, Kayo TI A three-dimensional variational data assimilation scheme for the Regional Ocean Modeling System: Implementation and basic experiments SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID COORDINATE; INTERPOLATION; SURFACE AB A three-dimensional variational data assimilation scheme for the Regional Ocean Modeling System (ROMS), named ROMS3DVAR, has been described in the work of Li et al. (2008). In this paper, ROMS3DVAR is applied to the central California coastal region, an area characterized by inhomogeneity and anisotropy, as well as by dynamically unbalanced flows. A method for estimating the model error variances from limited observations is presented, and the construction of the inhomogeneous and anisotropic error correlations based on the Kronecker product is demonstrated. A set of single observation experiments illustrates the inhomogeneous and anisotropic error correlations and weak dynamic constraints used. Results are presented from the assimilation of data gathered during the Autonomous Ocean Sampling Network (AOSN) experiment during August 2003. The results show that ROMS3DVAR is capable of reproducing complex flows associated with upwelling and relaxation, as well as the rapid transitions between them. Some difficulties encountered during the experiment are also discussed. C1 [Li, Zhijin; Chao, Yi] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [McWilliams, James C.; Ide, Kayo] Univ Calif Los Angeles, Dept Atmospher & Ocean Sci, Los Angeles, CA 90095 USA. [McWilliams, James C.; Ide, Kayo] Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90095 USA. RP Li, ZJ (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM zhijin.li@jpl.nasa.gov RI Ide, Kayo/F-8443-2010 NR 33 TC 39 Z9 40 U1 0 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD MAY 3 PY 2008 VL 113 IS C5 AR C05002 DI 10.1029/2006JC004042 PG 19 WC Oceanography SC Oceanography GA 297CT UT WOS:000255595400001 ER PT J AU Kroon, M Petropavlovskikh, I Shetter, R Hall, S Ullmann, K Veefkind, JP McPeters, RD Browell, EV Levelt, PF AF Kroon, M. Petropavlovskikh, I. Shetter, R. Hall, S. Ullmann, K. Veefkind, J. P. McPeters, R. D. Browell, E. V. Levelt, P. F. TI OMI total ozone column validation with Aura-AVE CAFS observations SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID MONITORING INSTRUMENT AB In this paper we present validation results of the total ozone column data products of the Ozone Monitoring Instrument (OMI) by using airborne observations by the CCD Actinic Flux Spectrometer (CAFS) instrument. CAFS was flown during Aura Validation Experiment (AVE) campaigns organized by NASA in support of the validation of EOS-Aura satellite data products. The accuracy of individual CAFS total ozone column estimates of 2.0% on average is sufficient to meet the OMI validation requirements of 3.0%. A climatology was used to estimate the ozone column below the aircraft altitude. AVE validation results show that the OMI-TOMS total ozone column data product is of overall high quality as CAFS and OMI-TOMS agree to within less than 1% with a standard deviation of 8 DU (2-3%) with no significant dependence on total ozone column, latitude, cloud fraction, or solar zenith angle. The primary shortcoming in OMI-DOAS collection 2 total ozone column data is the air mass factor reflected in the dependence on solar zenith angle of the CAFS and OMI-DOAS total ozone column difference. Fortunately, the CAFS aircraft data collected during AVE provided useful insights that could not be obtained in any other way into where OMI satellite data retrieval improvements were needed. For OMI-DOAS collection 3 the air mass factor issue has been solved by calibration optimization and retrieval algorithm improvements, bringing airborne CAFS and OMI-DOAS satellite data to agreement within less than 1.5% with a standard deviation of 9 DU (2-3%), in compliance with the OMI validation requirements. C1 [Kroon, M.; Veefkind, J. P.; Levelt, P. F.] Royal Netherlands Meteorol Inst, NL-3730 AE De Bilt, Netherlands. [Browell, E. V.] NASA, Langley Res Ctr, Hampton, VA 23681 USA. [Shetter, R.; Hall, S.; Ullmann, K.] Natl Ctr Atmospher Res, Boulder, CO 80305 USA. [McPeters, R. D.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Petropavlovskikh, I.] NOAA, Earth Syst Res Lab, Boulder, CO 80305 USA. RP Kroon, M (reprint author), Royal Netherlands Meteorol Inst, POB 201, NL-3730 AE De Bilt, Netherlands. EM mark.kroon@knmi.nl RI McPeters, Richard/G-4955-2013 OI McPeters, Richard/0000-0002-8926-8462 NR 23 TC 21 Z9 21 U1 1 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 2 PY 2008 VL 113 IS D15 AR D15S13 DI 10.1029/2007JD008795 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 297CJ UT WOS:000255594400002 ER PT J AU Marshak, A Wen, G Coakley, JA Remer, LA Loeb, NG Cahalan, RF AF Marshak, Alexander Wen, Guoyong Coakley, James A., Jr. Remer, Lorraine A. Loeb, Norman G. Cahalan, Robert F. TI A simple model for the cloud adjacency effect and the apparent bluing of aerosols near clouds SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID POLLUTION AEROSOL; BROKEN CLOUDS; PART I; SATELLITE; OCEAN; VALIDATION; PRODUCTS; SYSTEM; TERRA; SMOKE AB In determining aerosol-cloud interactions, the properties of aerosols must be characterized in the vicinity of clouds. Numerous studies based on satellite observations have reported that aerosol optical depths increase with increasing cloud cover. Part of the increase comes from the humidification and consequent growth of aerosol particles in the moist cloud environment, but part comes from 3-D cloud-radiative transfer effects on the retrieved aerosol properties. Often, discerning whether the observed increases in aerosol optical depths are artifacts or real proves difficult. The paper only addresses the cloud-clear sky radiative transfer interaction part. It provides a simple model that quantifies the enhanced illumination of cloud-free columns in the vicinity of clouds that are used in the aerosol retrievals. This model is based on the assumption that the enhancement in the cloud-free column radiance comes from enhanced Rayleigh scattering that results from the presence of the nearby clouds. This assumption leads to a larger increase of AOT for shorter wavelengths, or to a ``bluing'' of aerosols near clouds. The assumption that contribution from molecular scattering dominates over aerosol scattering and surface reflection is justified for the case of shorter wavelengths, dark surfaces, and an aerosol layer below the cloud tops. The enhancement in Rayleigh scattering is estimated using a stochastic cloud model to obtain the radiative flux reflected by broken clouds and comparing this flux with that obtained with the molecules in the atmosphere causing extinction, but no scattering. C1 [Marshak, Alexander; Remer, Lorraine A.; Cahalan, Robert F.] NASA, Goddard Space Flight Ctr, Climate & Radiat Branch, Greenbelt, MD 20771 USA. [Wen, Guoyong] Univ Maryland, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21250 USA. [Coakley, James A., Jr.] Oregon State Univ, Coll Ocean & Atmospher Sci, Corvallis, OR 97331 USA. [Loeb, Norman G.] NASA, Langley Res Ctr, Climate Sci Branch, Hampton, VA 23681 USA. RP Marshak, A (reprint author), NASA, Goddard Space Flight Ctr, Climate & Radiat Branch, Greenbelt, MD 20771 USA. EM alexander.marshak@nasa.gov RI Marshak, Alexander/D-5671-2012; Cahalan, Robert/E-3462-2012 OI Cahalan, Robert/0000-0001-9724-1270 NR 26 TC 79 Z9 80 U1 1 U2 12 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 2 PY 2008 VL 113 IS D14 AR D14S17 DI 10.1029/2007JD009196 PG 7 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 297CG UT WOS:000255594100001 ER PT J AU McPeters, R Kroon, M Labow, G Brinksma, E Balis, D Petropavlovskikh, I Veefkind, JP Bhartia, PK Levelt, PF AF McPeters, R. Kroon, M. Labow, G. Brinksma, E. Balis, D. Petropavlovskikh, I. Veefkind, J. P. Bhartia, P. K. Levelt, P. F. TI Validation of the Aura Ozone Monitoring Instrument total column ozone product SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID STANDARD AB This paper is an overview of the validation of the total column ozone data products from the Ozone Monitoring Instrument (OMI) on board the NASA EOS- Aura satellite. OMI is an imaging UV/visible spectrometer that maps global ozone on a daily basis. There are two ozone products from OMI, one derived using the traditional TOMS retrieval algorithm and another derived using a Differential Optical Absorption Spectroscopy algorithm that is being developed to take advantage of the hyperspectral capabilities of OMI. Validation is primarily performed through comparison with a network of Dobson and Brewer ground stations and secondarily through campaigns conducted specifically to validate Aura. Comparison with an ensemble of 76 Northern Hemisphere ground stations shows that OMI-TOMS total column ozone averages 0.4% higher than the station average, with station-to-station standard deviation of +/- 0.6%. The comparison shows that the OMI-TOMS ozone was stable over the 2-year period with no evidence of drift relative to the ground network. The OMI-DOAS product is also stable but with a 1.1% offset and a seasonal variation of +/- 2%. During four aircraft validation campaigns using the NASA DC-8 and WB-57 aircraft, ozone above the aircraft was measured using an actinic flux instrument and compared with OMI ozone. These comparisons showed agreement within 2% over a broad range of latitude and viewing conditions. Only during the high-latitude flights did the OMI-DOAS ozone show the effects of a solar zenith angle dependent error. C1 [McPeters, R.; Bhartia, P. K.] NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. [Balis, D.] Aristotle Univ Thessaloniki, GR-54124 Thessaloniki, Greece. [Kroon, M.; Brinksma, E.; Veefkind, J. P.; Levelt, P. F.] Royal Netherlands Meteorol Inst, NL-3730 AE De Bilt, Netherlands. [Labow, G.] Sci Syst & Applicat Inc, Lanham, MD 20706 USA. [Petropavlovskikh, I.] NOAA, ESRL, Boulder, CO 80305 USA. RP McPeters, R (reprint author), NASA, Goddard Space Flight Ctr, Atmospheres Lab, Code 613-3, Greenbelt, MD 20771 USA. RI McPeters, Richard/G-4955-2013 OI McPeters, Richard/0000-0002-8926-8462 NR 18 TC 88 Z9 90 U1 0 U2 8 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 2 PY 2008 VL 113 IS D15 AR D15S14 DI 10.1029/2007JD008802 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 297CJ UT WOS:000255594400003 ER PT J AU Schwartz, MJ Lambert, A Manney, GL Read, WG Livesey, NJ Froidevaux, L Ao, CO Bernath, PF Boone, CD Cofield, RE Daffer, WH Drouin, BJ Fetzer, EJ Fuller, RA Jarnot, RF Jiang, JH Jiang, YB Knosp, BW Kruger, K Li, JLF Mlynczak, MG Pawson, S Russell, JM Santee, ML Snyder, WV Stek, PC Thurstans, RP Tompkins, AM Wagner, PA Walker, KA Waters, JW Wu, DL AF Schwartz, M. J. Lambert, A. Manney, G. L. Read, W. G. Livesey, N. J. Froidevaux, L. Ao, C. O. Bernath, P. F. Boone, C. D. Cofield, R. E. Daffer, W. H. Drouin, B. J. Fetzer, E. J. Fuller, R. A. Jarnot, R. F. Jiang, J. H. Jiang, Y. B. Knosp, B. W. Krueger, K. Li, J. -L. F. Mlynczak, M. G. Pawson, S. Russell, J. M., III Santee, M. L. Snyder, W. V. Stek, P. C. Thurstans, R. P. Tompkins, A. M. Wagner, P. A. Walker, K. A. Waters, J. W. Wu, D. L. TI Validation of the aura microwave limb sounder temperature and geopotential height measurements SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID RADIO OCCULTATION; EOS MLS; ATMOSPHERIC PROFILES; RETRIEVAL; CALIBRATION; SATELLITE; MISSION; SYSTEM; MODEL; AIRS AB Global satellite observations of temperature and geopotential height (GPH) from the Microwave Limb Sounder (MLS) on the EOS Aura spacecraft are discussed. The precision, resolution, and accuracy of the data produced by the MLS version 2.2 processing algorithms are quantified, and recommendations for data screening are made. Temperature precision is 1 K or better from 316 hPa to 3.16 hPa, degrading to similar to 3 K at 0.001 hPa. The vertical resolution is 3 km at 31.6 hPa, degrading to 6 km at 316 hPa and to similar to 13 km at 0.001 hPa. Comparisons with analyses (Goddard Earth Observing System version 5.0.1 (GEOS-5), European Centre for Medium-range Weather Forecasts (ECMWF), Met Office (MetO)) and other observations (CHAllenging Minisatellite Payload (CHAMP), Atmospheric Infrared Sounder/Advanced Microwave Sounder Unit (AIRS/AMSU), Sounding of the Atmosphere using Broadband Radiometry (SABER), Halogen Occultation Experiment (HALOE), Atmospheric Chemistry Experiment (ACE), radiosondes) indicate that MLS temperature has persistent, pressure-dependent biases which are between -2.5 K and +1 K between 316 hPa and 10 hPa. The 100-hPa MLS v2.2 GPH surface has a bias of similar to 150 m relative to the GEOS-5 values. These biases are compared to modeled systematic uncertainties. GPH biases relative to correlative measurements generally increase with height owing to an overall cold bias in MLS temperature relative to correlative temperature measurements in the upper stratosphere and mesosphere. C1 [Schwartz, M. J.; Lambert, A.; Manney, G. L.; Read, W. G.; Livesey, N. J.; Froidevaux, L.; Ao, C. O.; Cofield, R. E.; Daffer, W. H.; Drouin, B. J.; Fetzer, E. J.; Fuller, R. A.; Jarnot, R. F.; Jiang, J. H.; Jiang, Y. B.; Knosp, B. W.; Li, J. -L. F.; Santee, M. L.; Snyder, W. V.; Stek, P. C.; Thurstans, R. P.; Wagner, P. A.; Waters, J. W.; Wu, D. L.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Boone, C. D.] Univ Waterloo, Dept Chem, Waterloo, ON N2L 3G1, Canada. [Krueger, K.] Univ Kiel, IFM GEOMAR, Leibniz Inst Marine Sci, D-24148 Kiel, Germany. [Mlynczak, M. G.] NASA, Langley Res Ctr, Hampton, VA 23681 USA. [Pawson, S.] NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Greenbelt, MD 20771 USA. [Russell, J. M., III] Hampton Univ, Hampton, VA 23668 USA. [Tompkins, A. M.] European Ctr Medium Range Weather Forecasts, Reading RG1 1NT, Berks, England. [Manney, G. L.] New Mexico Inst Min & Technol, Dept Phys, Socorro, NM 87801 USA. RP Schwartz, MJ (reprint author), CALTECH, Jet Prop Lab, Mail Stop 183-701,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM michael.j.schwartz@jpl.nasa.gov RI Bernath, Peter/B-6567-2012; Mlynczak, Martin/K-3396-2012; Tompkins, Adrian/N-6472-2013; Schwartz, Michael/F-5172-2016; Wu, Dong/D-5375-2012; Pawson, Steven/I-1865-2014 OI Bernath, Peter/0000-0002-1255-396X; Tompkins, Adrian/0000-0003-0975-6691; Schwartz, Michael/0000-0001-6169-5094; Pawson, Steven/0000-0003-0200-717X NR 45 TC 193 Z9 196 U1 3 U2 11 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 2 PY 2008 VL 113 IS D15 AR D15S11 DI 10.1029/2007JD008783 PG 23 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 297CJ UT WOS:000255594400001 ER PT J AU Brown, ME Funk, CC Verdin, J Eilerts, G AF Brown, Molly E. Funk, Christopher C. Verdin, James Eilerts, Gary TI Ensuring food security - Response SO SCIENCE LA English DT Letter C1 [Brown, Molly E.] NASA, SSAI, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Funk, Christopher C.] Univ Calif Santa Barbara, Dept Geog, Santa Barbara, CA 93106 USA. [Verdin, James] US Geol Survey, Sioux Falls, SD 57198 USA. [Eilerts, Gary] US Agcy Int Dev, Washington, DC 20523 USA. RP Brown, ME (reprint author), NASA, SSAI, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RI Brown, Molly/E-2724-2010; Brown, Molly/M-5146-2013 OI Brown, Molly/0000-0001-7384-3314; Brown, Molly/0000-0001-7384-3314 NR 4 TC 0 Z9 0 U1 1 U2 4 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 EI 1095-9203 J9 SCIENCE JI Science PD MAY 2 PY 2008 VL 320 IS 5876 BP 611 EP 612 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 295DD UT WOS:000255454300017 ER PT J AU Sperber, KR Slingo, JM Waliser, DE Inness, PM AF Sperber, Kenneth R. Slingo, Julia M. Waliser, Duane E. Inness, Peter M. TI Coarse-resolution models only partly cloudy SO SCIENCE LA English DT Letter ID MADDEN-JULIAN OSCILLATION; GENERAL-CIRCULATION MODEL; INTRASEASONAL OSCILLATIONS; SIMULATION C1 [Sperber, Kenneth R.] Lawrence Livermore Natl Lab, Program Climate Model Diag & Intercomparison, Livermore, CA 94551 USA. [Slingo, Julia M.; Inness, Peter M.] Univ Reading, Natl Ctr Atmospher Res, Reading RG6 6BB, Berks, England. [Slingo, Julia M.; Inness, Peter M.] Univ Reading, Walker Inst, Reading RG6 6BB, Berks, England. [Waliser, Duane E.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Sperber, KR (reprint author), Lawrence Livermore Natl Lab, Program Climate Model Diag & Intercomparison, POB 808,L-103, Livermore, CA 94551 USA. EM sperber1@llnl.gov RI Sperber, Kenneth/H-2333-2012 NR 9 TC 8 Z9 8 U1 0 U2 2 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD MAY 2 PY 2008 VL 320 IS 5876 BP 612 EP 612 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 295DD UT WOS:000255454300018 PM 18451284 ER PT J AU Sobieszczanski-Sobieski, J AF Sobieszczanski-Sobieski, Jaroslaw TI Integrated system-of-systems synthesis SO AIAA JOURNAL LA English DT Article; Proceedings Paper CT AIAA/ISSMO 11th Multidisciplinary Analysis and Optimization Conference CY SEP 06-08, 2006 CL Portsmouth, VA SP Amer Inst Aeronaut & Astronaut, ISSMO ID OPTIMIZATION AB This paper defines a system of systems as an assemblage of components organized in three levels, each level featuring both analysis and optimization. The choice of only three levels is deliberate, based on examination of the nature of a system of systems, a sample of references, and the range of potential applications. The solution methodology introduced in the paper derives as an extension of an existing bilevel integrated system synthesis method for which an application and implementation experience, as well as rigorous proof of correctness, are available. The new method, called trilevel integrated system synthesis, addresses the engineering practice requirements discussed in the paper. It builds on the formal representation of the system-of-systems coupling data known as the data dependency matrix, on the use of surrogate models, and on a recursive similarity of the data coupling among the systems in a system of systems and among the components within the system. The paper defines three variants of trilevel integrated system synthesis and identifies one of the three for implementation by the criteria of computational cost and engineering practicality. The closing discussion points out that because of extraordinary cost development and doubtful utility of simplified test cases, a system-of-systems optimization method ought to be developed in conjunction with a real, full-scale, application. C1 NASA Langley Res Ctr, Res & Technol Directorate, Hampton, VA USA. RP Sobieszczanski-Sobieski, J (reprint author), NASA Langley Res Ctr, Res & Technol Directorate, Mail Stop 188E, Hampton, VA USA. EM Jaroslaw.Sobieski-1@nasa.gov NR 22 TC 11 Z9 12 U1 0 U2 3 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0001-1452 J9 AIAA J JI AIAA J. PD MAY PY 2008 VL 46 IS 5 BP 1072 EP 1080 DI 10.2514/1.27953 PG 9 WC Engineering, Aerospace SC Engineering GA 295SJ UT WOS:000255493900006 ER PT J AU Lane, MD Bishop, JL Dyar, MD King, PL Parente, M Hyde, BC AF Lane, Melissa D. Bishop, Janice L. Dyar, M. Darby King, Penelope L. Parente, Mario Hyde, Brendt C. TI Mineralogy of the Paso Robles soils on Mars SO AMERICAN MINERALOGIST LA English DT Article DE Mars; spectroscopy; sulfate; phosphate; mineralogy; spectra; Paso Robles; acid ID SULFATE MINERALS; IRON SULFATE; SPECTROSCOPY; REFLECTANCE; ASSEMBLAGES; MOSSBAUER; CHEMISTRY AB Visible, near-infrared, thermal, and Mossbauer spectroscopic data from the exposed, bright track soil at the "Paso Robles" site within Gusev crater, Mars, indicate the presence of Fe3+-sulfates and possibly Fe3+-phosphates admixed with the host soil. When the spectroscopic analyses are combined with constraints imposed by chemical data, the determined dominant Fe3+-sulfate component is hydrous, and all of the spectroscopic methods suggest that it is probably ferricopiapite or some closely related, structurally similar species, possibly mixed with other Fe3+ sulfates such as butlerite or parabutlerite, or perhaps (para)coquimbite, fibroferrite, or metahohmanite. Such an assemblage is consistent with formation in a highly oxidized, relatively dehydrated environment with the bulk-sulfate assemblage having OH/(OH + 2SO(4)) of < similar to 0.4. Some Fe3+ is likely to be associated with phosphates in the soil in the form of ferristrunzite or strengite. C1 [Lane, Melissa D.] Planetary Sci Inst, Tucson, AZ 85719 USA. [Bishop, Janice L.] NASA, SETI Inst, Ames Res Ctr, Mountain View, CA 94043 USA. [Dyar, M. Darby] Mt Holyoke Coll, S Hadley, MA 01075 USA. [King, Penelope L.; Hyde, Brendt C.] Univ Western Ontario, London, ON N6A 5B7, Canada. [Parente, Mario] Stanford Univ, Stanford, CA 94305 USA. RP Lane, MD (reprint author), Planetary Sci Inst, Tucson, AZ 85719 USA. EM lane@psi.edu RI King, Penelope/A-1791-2011 OI King, Penelope/0000-0002-8364-9168 NR 46 TC 57 Z9 57 U1 1 U2 16 PU MINERALOGICAL SOC AMER PI CHANTILLY PA 3635 CONCORDE PKWY STE 500, CHANTILLY, VA 20151-1125 USA SN 0003-004X EI 1945-3027 J9 AM MINERAL JI Am. Miner. PD MAY-JUN PY 2008 VL 93 IS 5-6 BP 728 EP 739 DI 10.2138/am.2008.2757 PG 12 WC Geochemistry & Geophysics; Mineralogy SC Geochemistry & Geophysics; Mineralogy GA 304UB UT WOS:000256133500002 ER PT J AU Ross, KW Morris, DK Johannsen, CJ AF Ross, K. W. Morris, D. K. Johannsen, C. J. TI A review of intra-field yield estimation from yield monitor data SO APPLIED ENGINEERING IN AGRICULTURE LA English DT Article DE yield monitor; yield map; precision agriculture; mixing flow models; non-mixing flow models; remote sensing ID GRAIN FLOW MODEL; COMBINE HARVESTER; PRECISION AGRICULTURE; TIME; ACCURACY; SYSTEM; MAPS AB In this review, the process of estimating crop yield from yield monitor data is traced from the instant of harvest, through combine processes and sensing, to post-harvest processing, yield estimation and mapping. Unified notation is applied for easy comparison. Models for various components contributing to mapped yield estimates are detailed. These include approaches to determining basic properties such as combine position, gathering width and area swept out as a function of time. Special attention is given to comparison of the commonly-used deterministic flow model with several probabalistic alternatives that have been offered. Though there has been little success in using flow models to mitigate mixing effects, the results have been better for determining transport delay. Post processing is discussed, including yield data screening as well as mapping. The recent integration of remote sensing with yield monitor data is described. In the proper context, this integration of remote sensing shows potential to increase the accuracy and spatial resolution of yield mapping. C1 [Ross, K. W.] Sci Syst & Applicat Inc, John C Stennis Space Ctr, Stennis Space Ctr, MS 39529 USA. [Morris, D. K.] Louisiana State Univ, AgCtr, Dept Biol & Agr Engn, Baton Rouge, LA 70803 USA. [Johannsen, C. J.] Purdue Univ, Dept Agron, Applicat Remote Sensing Lab, W Lafayette, IN 47907 USA. RP Ross, KW (reprint author), Sci Syst & Applicat Inc, John C Stennis Space Ctr, Bldg 1105, Stennis Space Ctr, MS 39529 USA. EM W.Ross@nasa.gov OI Ross, Kenton/0000-0002-6381-5894 NR 41 TC 4 Z9 4 U1 2 U2 5 PU AMER SOC AGRICULTURAL & BIOLOGICAL ENGINEERS PI ST JOSEPH PA 2950 NILES RD, ST JOSEPH, MI 49085-9659 USA SN 0883-8542 J9 APPL ENG AGRIC JI Appl. Eng. Agric. PD MAY PY 2008 VL 24 IS 3 BP 309 EP 317 PG 9 WC Agricultural Engineering SC Agriculture GA 310TL UT WOS:000256553200006 ER PT J AU Kotchenova, SY Vermote, EF Levy, R Lyapustin, A AF Kotchenova, Svetlana Y. Vermote, Eric F. Levy, Robert Lyapustin, Alexei TI Radiative transfer codes for atmospheric correction and aerosol retrieval: intercomparison study SO APPLIED OPTICS LA English DT Article ID MULTIPLE-SCATTERING; POLARIZATION; REFLECTANCE; MODTRAN4; UPGRADES; ERRORS; MEDIA; CLOUD; MODEL AB Results are summarized for a scientific project devoted to the comparison of four atmospheric radiative transfer codes incorporated into different satellite data processing algorithms, namely, 6SV1.1 (second simulation of a satellite signal in the solar spectrum, vector, version 1.1), RT3 (radiative transfer), MODTRAN (moderate resolution atmospheric transmittance and radiance code), and SHARM (spherical harmonics). The performance of the codes is tested against well-known benchmarks, such as Coulson's tabulated values and a Monte Carlo code. The influence of revealed differences on aerosol optical thickness and surface reflectance retrieval is estimated theoretically by using a simple mathematical approach. All information about the project can be found at http://rtcodes.ltdri.org. (C) 2008 Optical Society of America. C1 [Kotchenova, Svetlana Y.; Vermote, Eric F.] Univ Maryland, Dept Geog, College Pk, MD 20740 USA. [Levy, Robert] Sci Syst & Applicat Inc, Lanham, MD 20706 USA. [Levy, Robert] NASA, Goddard Space Flight Ctr, Climate & Radiat Branch, Greenbelt, MD 20771 USA. [Lyapustin, Alexei] Univ Maryland Baltimore Cty, Goddard Earth Sci Technol Ctr, Greenbelt, MD 20771 USA. RP Kotchenova, SY (reprint author), Univ Maryland, Dept Geog, 4321 Hartwick Rd,Suite 209, College Pk, MD 20740 USA. EM skotchen@ltdri.org RI Vermote, Eric/K-3733-2012; Levy, Robert/M-7764-2013; Lyapustin, Alexei/H-9924-2014 OI Levy, Robert/0000-0002-8933-5303; Lyapustin, Alexei/0000-0003-1105-5739 NR 34 TC 43 Z9 43 U1 3 U2 10 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD MAY 1 PY 2008 VL 47 IS 13 BP 2215 EP 2226 DI 10.1364/AO.47.002215 PG 12 WC Optics SC Optics GA 308CD UT WOS:000256365000057 PM 18449285 ER PT J AU Mengshoel, OJ AF Mengshoel, Ole J. TI Understanding the role of noise in stochastic local search: Analysis and experiments SO ARTIFICIAL INTELLIGENCE LA English DT Article DE stochastic local search; noise; Markov chain models; expected hitting times; rational functions; noise response curves; probabilistic reasoning; Bayesian networks; most probable explanation; systematic experiments; polynomial approximation; convexity ID BELIEF NETWORKS; NP-HARD; ALGORITHMS; SAT; COMPLEXITY; MAPS AB Stochastic local search (SLS) algorithms have recently been proven to be among the best approaches to solving computationally hard problems. SLS algorithms typically have a number of parameters, optimized empirically, that characterize and determine their performance. In this article, we focus on the noise parameter. The theoretical foundation of SLS, including an understanding of how to the optimal noise varies with problem difficulty, is lagging compared to the strong empirical results obtained using these algorithms. A purely empirical approach to understanding and optimizing SLS noise, as problem instances vary, can be very computationally intensive. To complement existing experimental results, we formulate and analyze several Markov chain models of SLS in this article. In particular, we compute expected hitting times and show that they are rational functions for individual problem instances as well as their mixtures. Expected hitting time curves are analytical counterparts to noise response curves reported in the experimental literature. Hitting time analysis using polynomials and convex functions is also discussed. In addition, we present examples and experimental results illustrating the impact of varying noise probability on SLS run time. In experiments, where most probable explanations in Bayesian networks are computed, we use synthetic problem instances as well as problem instances from applications. We believe that our results provide an improved theoretical understanding of the role of noise in stochastic local search, thereby providing a foundation for further progress in this area. (C) 2008 Elsevier B.V. All rights reserved. C1 NASA, Ames Res Ctr, RIACS, Moffett Field, CA 94035 USA. RP Mengshoel, OJ (reprint author), NASA, Ames Res Ctr, RIACS, Mail Stop 269-3, Moffett Field, CA 94035 USA. EM omengshoel@riacs.edu NR 51 TC 11 Z9 11 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0004-3702 EI 1872-7921 J9 ARTIF INTELL JI Artif. Intell. PD MAY PY 2008 VL 172 IS 8-9 BP 955 EP 990 DI 10.1016/j.artint.2007.09.010 PG 36 WC Computer Science, Artificial Intelligence SC Computer Science GA 295DM UT WOS:000255455200003 ER PT J AU Teixeira, J Kim, YJ AF Teixeira, Joao Kim, Young-Joon TI On a simple parameterization of convective cloud fraction SO ASIA-PACIFIC JOURNAL OF ATMOSPHERIC SCIENCES LA English DT Article DE convective cloud fraction; parameterization; global forecast model; NOGAPS ID BOUNDARY-LAYER CLOUDS; LARGE-SCALE MODELS; CUMULUS CONVECTION; PREDICTION SYSTEM; SCHEME; WATER; REPRESENTATION; LIQUID; COVER AB A simple system of prognostic equations for cloud fraction and cloud water due to moist convection is discussed. In this parameterization there is a convective detrainment source term and a sink term due to turbulent erosion. Assuming that there is a balance between the two terms leads to simple steady-state solutions. This approach is tested against results from a cloud resolving model for two deep convection cases and is implemented and evaluated in the Navy Operational Global Atmospheric Prediction System (NOGAPS). Despite its simplicity, this parameterization produces realistic values of cloud fraction and improves the quality of total and high cloud cover, and outgoing longwave radiation in the tropics. C1 [Teixeira, Joao] UCAR VSP, Naval Res Lab, Monterey, CA USA. [Teixeira, Joao] NATO Undersea Res Ctr, La Spezia, Italy. RP Teixeira, J (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,MS 169-237, Pasadena, CA 91109 USA. EM teixeira@jpl.nasa.gov NR 31 TC 0 Z9 0 U1 0 U2 0 PU KOREAN METEOROLOGICAL SOC PI SEOUL PA SHINKIL-DONG 508, SIWON BLDG 704, YONGDUNGPO-GU, SEOUL, 150-050, SOUTH KOREA SN 1976-7633 J9 ASIA-PAC J ATMOS SCI JI Asia-Pac. J. Atmos. Sci. PD MAY PY 2008 VL 44 IS 2 BP 191 EP 199 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 334PZ UT WOS:000258235000007 ER PT J AU Stiles, BW Kirk, RL Lorenz, RD Hensley, S Lee, E Ostro, SJ Allison, MD Callahan, PS Gim, YY Iess, L Del Marmo, PP Hamilton, G Johnson, WTK West, RD AF Stiles, Bryan W. Kirk, Randolph L. Lorenz, Ralph D. Hensley, Scott Lee, Ella Ostro, Steven J. Allison, Michael D. Callahan, Philip S. Gim, Yonggyu Iess, Luciano Del Marmo, Paolo Perci Hamilton, Gary Johnson, William T. K. West, Richard D. CA Cassini RADAR Team TI Determining Titan's spin state from Cassini RADAR images SO ASTRONOMICAL JOURNAL LA English DT Article DE celestial mechanics; methods : numerical; planets and satellites : individual (Titan); techniques : image processing; techniques : radar astronomy AB For some 19 areas of Titan's surface, the Cassini RADAR instrument has obtained synthetic aperture radar (SAR) images during two different flybys. The time interval between flybys varies from several weeks to two years. We have used the apparent misregistration (by 10-30 km) of features between separate flybys to construct a refined model of Titan's spin state, estimating six parameters: north pole right ascension and declination, spin rate, and these quantities' first time derivatives We determine a pole location with right ascension of 39.48 degrees and declination of 83.43 degrees corresponding to a 0.3 degree obliquity. We determine the spin rate to be 22.5781 deg day(-1) or 0.001 deg day(-1) faster than the synchronous spin rate. Our estimated corrections to the pole and spin rate exceed their corresponding standard errors by factors of 80 and 8, respectively. We also found that the rate of change in the pole right ascension is -30 deg century(-1), ten times faster than right ascension rate of change for the orbit normal. The spin rate is increasing at a rate of 0.05 deg day(-1) per century. We observed no significant change in pole declination over the period for which we have data. Applying our pole correction reduces the feature misregistration from tens of km to 3 km. Applying the spin rate and derivative corrections further reduces the misregistration to 1.2 km. C1 [Stiles, Bryan W.; Hensley, Scott; Ostro, Steven J.; Callahan, Philip S.; Gim, Yonggyu; Hamilton, Gary; Johnson, William T. K.; West, Richard D.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Kirk, Randolph L.; Lee, Ella] US Geol Survey, Flagstaff, AZ 86001 USA. [Lorenz, Ralph D.] Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. [Allison, Michael D.] NASA, Goddard Inst Space Studies, New York, NY 10025 USA. [Iess, Luciano; Del Marmo, Paolo Perci] Univ Rome, Dept Aerosp Engn & Astronaut, Rome, Italy. RP Stiles, BW (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. RI IESS, Luciano/F-4902-2011; Lorenz, Ralph/B-8759-2016 OI IESS, Luciano/0000-0002-6230-5825; Lorenz, Ralph/0000-0001-8528-4644 NR 9 TC 54 Z9 54 U1 1 U2 8 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0004-6256 J9 ASTRON J JI Astron. J. PD MAY PY 2008 VL 135 IS 5 BP 1669 EP 1680 DI 10.1088/0004-6256/135/5/1669 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 294LO UT WOS:000255407700002 ER PT J AU Croft, S Van Breugel, W Brown, MJI de Vries, W Dey, A Eisenhardt, P Jannuzi, B Rottgering, HR Stanford, SA Stern, D Willner, SP AF Croft, Steve Van Breugel, Wil Brown, Michael J. I. de Vries, Wim Dey, Arjun Eisenhardt, Peter Jannuzi, Buell Rottgering, Huub R. Stanford, S. A. Stern, Daniel Willner, S. P. TI Radio-loud high-redshift protogalaxy candidates in Bootes SO ASTRONOMICAL JOURNAL LA English DT Article DE galaxies : active; galaxies : high-redshift; galaxies : starburst; infrared : galaxies ID IRAC SHALLOW SURVEY; RAY SOURCE CATALOG; ARRAY CAMERA IRAC; WIDE-FIELD SURVEY; PHOTOMETRIC REDSHIFTS; ELLIPTIC GALAXIES; 1.4 GHZ; LUMINOSITY; TELESCOPE; XBOOTES AB We used the Near Infrared Camera on Keck I to obtain K-s-band images of four candidate high-redshift radio lgalaxies selected using optical and radio data in the NOAO Deep Wide-Field Survey in Bootes. Our targets have 1.4 GHz radio flux densities greater than 1 mJy, but are undetected in the optical to greater than or similar to 24 Vega mag. Spectral energy distribution fitting suggests that three of these objects are at z > 3, with radio luminosities near the FR-I/FR-II break. The other has photometric redshift z(phot) = 1.2, but may in fact be at higher redshift. Two of the four objects exhibit diffuse morphologies in K-s-band, suggesting that they are still in the process of forming. C1 [Croft, Steve; Van Breugel, Wil; de Vries, Wim; Stanford, S. A.] Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. [Croft, Steve; Van Breugel, Wil] Univ Calif Merced, Merced, CA 95344 USA. [Croft, Steve; de Vries, Wim; Stanford, S. A.] Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. [Croft, Steve] Univ Calif Berkeley, Berkeley, CA 94720 USA. [Brown, Michael J. I.] Monash Univ, Sch Phys, Clayton, Vic 3168, Australia. [Dey, Arjun; Jannuzi, Buell] Natl Opt Astron Observ, Tucson, AZ 85719 USA. [Eisenhardt, Peter; Stern, Daniel] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Rottgering, Huub R.] Leiden Observ, NL-2333 CA Leiden, Netherlands. [Willner, S. P.] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Croft, S (reprint author), Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, L-413,7000 East Ave, Livermore, CA 94550 USA. RI Brown, Michael/B-1181-2015; OI Brown, Michael/0000-0002-1207-9137; Croft, Steve/0000-0003-4823-129X NR 39 TC 5 Z9 5 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0004-6256 J9 ASTRON J JI Astron. J. PD MAY PY 2008 VL 135 IS 5 BP 1793 EP 1802 DI 10.1088/0004-6256/135/5/1793 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 294LO UT WOS:000255407700014 ER PT J AU Turner, TJ Reeves, JN Kraemer, SB Miller, L AF Turner, T. J. Reeves, J. N. Kraemer, S. B. Miller, L. TI Tracing a disk wind in NGC 3516 SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE X-rays : galaxies; black hole physics; galaxies : Seyfert ID ACTIVE GALACTIC NUCLEI; NARROW-LINE REGION; BLACK-HOLE MASS; SEYFERT-GALAXIES; ALPHA PROFILE; IRON LINE; EMISSION; ABSORPTION; SPECTROSCOPY; VARIABILITY AB Context. X-ray spectra of AGN often contain signatures indicative of absorption in multiple layers of gas whose ionization-state and covering fraction may vary with time. It has been unclear to date how much of the observed X-ray spectral and timing behavior in AGN can be attributed to variations in absorption, versus variations in the strengths of emission or reflection components. Diagnostics of the inner regions of AGN cannot be reliably performed until the origin of observed effects is understood. Aims. We investigate the role of the X-ray absorbers in the Seyfert 1 galaxy NGC 3516. Methods. Time-averaged and flux-selected spectroscopy is used to examine the behavior of NGC 3516 observed in Chandra HETG and XMM data from Oct. 2006. Results. New H-like and He-like emission and absorption features discovered in the Fe K regime reveal a previously unknown zone of circumnuclear gas in NGC 3516 with log xi similar to 4.3 and column density similar to 10(23) cm(-2). A lower-ionization layer with log xi similar to 2 and of similar column density is confirmed from previous observations, this layer has a covering fraction around 50%, and changes in covering provide a simple explanation of a deep dip in the light curve that we interpret as an eclipse of the continuum due to passage of a cloud across the sight line within half a day. These inner zones of absorbing gas are detected to have outflow velocities in the range 1000-2000 km s(-1), this, and constraints on radial location are consistent with an origin as part of a disk wind in NGC 3516. C1 [Turner, T. J.] Univ Maryland Baltimore Cty, Dept Phys, Baltimore, MD 21250 USA. [Turner, T. J.] NASA, Goddard Space Flight Ctr, Explorat Universe Div, Greenbelt, MD 20771 USA. [Reeves, J. N.] Univ Keele, Sch Phys & Geog Sci, Astrophys Grp, Keele ST5 5BG, Staffs, England. [Kraemer, S. B.] Catholic Univ Amer, Dept Phys, Washington, DC 20064 USA. [Miller, L.] Univ Oxford, Dept Phys, Oxford OX1 3RH, England. RP Turner, TJ (reprint author), Univ Maryland Baltimore Cty, Dept Phys, 1000 Hilltop Circle, Baltimore, MD 21250 USA. EM turner@milkyway.gsfc.nasa.gov NR 29 TC 70 Z9 70 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAY PY 2008 VL 483 IS 1 BP 161 EP 169 DI 10.1051/0004-6361:20078808 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 294NR UT WOS:000255413300020 ER PT J AU Miller, L Turner, TJ Reeves, JN AF Miller, L. Turner, T. J. Reeves, J. N. TI An absorption origin for the X-ray spectral variability of MCG-6-30-15 SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE accretion, accretion disks; galaxies : active; galaxies : individual : MCG-6-30-15; galaxies : Seyfert ID ACTIVE GALACTIC NUCLEI; K-ALPHA LINE; SEYFERT-GALAXY MCG-6-30-15; XMM-NEWTON OBSERVATION; ACCRETING BLACK-HOLES; DUSTY WARM ABSORBER; IRON-LINE; GRATING SPECTROMETER; COLD MATTER; LONG HARD AB Context. The Seyfert I galaxy MCG-6-30-15 shows one of the best examples of a broad "red wing" of emission in its X-ray spectrum at energies 2 < E < 6.4 keV, commonly interpreted as being caused by relativistically-blurred reflection close to the event horizon of the black hole. Aims. We aim to test an alternative model in which absorption creates the observed spectral shape, explains the puzzling lack of variability of the red wing and reduces the high reflection albedo, substantially greater than unity, that is otherwise inferred at energies E > 20 keV. Methods. We compiled all the available long-exposure, high-quality data for MCG-6-30-15: 522 ks of Chandra HETGS, 282 ks of XMM-Newton PN/RGS and 253 ks of Suzaku XIS/PIN data. This is the first analysis of this full dataset. We investigated the spectral variability on timescales > 20 ks using principal components analysis and fitted spectral models to "flux state" and mean spectra over the energy range 0.5-45 keV ( depending on detector). The absorber model was based on the zones previously identified in the high-resolution grating data. Joint fits were carried out to any data that were simultaneous. Results. Multiple absorbing zones covering a wide range of ionisation are required by the grating data, including a highly ionised outflowing zone. A variable partial-covering zone plus absorbed low-ionisation reflection, distant from the source, provides a complete description of the variable X-ray spectrum. A single model fits all the data. We conclude that these zones are responsible for the red wing, its apparent lack of variability, the absorption structure around the FeK alpha line, the soft-band "excess" and the high flux seen in the hard X-ray band. A relativistically-blurred Fe line is not required in this model. We suggest the partial covering zone is a clumpy wind from the accretion disk. C1 [Miller, L.] Univ Oxford, Dept Phys, Oxford OX1 3RH, England. [Turner, T. J.] Univ Maryland Baltimore Cty, Dept Phys, Baltimore, MD 21250 USA. [Turner, T. J.] NASA, Goddard Space Flight Ctr, Astrophys Sci Div, Greenbelt, MD 20771 USA. [Reeves, J. N.] Univ Keele, Sch Phys & Geog Sci, Astrophys Grp, Keele ST5 5BG, Staffs, England. RP Miller, L (reprint author), Univ Oxford, Dept Phys, Denys Wilkinson Bldg,Keble Rd, Oxford OX1 3RH, England. EM lam@astro.ox.ac.uk RI XRAY, SUZAKU/A-1808-2009 NR 80 TC 124 Z9 124 U1 2 U2 2 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 1432-0746 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAY PY 2008 VL 483 IS 2 BP 437 EP 452 DI 10.1051/0004-6361:200809590 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 299EB UT WOS:000255737500010 ER PT J AU Fludra, A Ireland, J AF Fludra, A. Ireland, J. TI Radiative and magnetic properties of solar active regions SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE Sun : UV radiation; Sun : magnetic fields; Sun : corona; Sun : transition region ID CORONAL HEATING MODELS; LONG-TERM EVOLUTION; SOFT-X-RAY; ULTRAVIOLET; LOOPS; FIELD; PARAMETERS; EMISSION; AR-7978; STARS AB Context. The relationships between the photospheric magnetic flux and either the X-ray or extreme ultraviolet emission from the solar atmosphere have been studied by several authors. Power-law relations have been found between the total magnetic flux and X-ray flux or intensities of the chromospheric, transition region, and coronal emission lines in solar active regions. These relations were then used to infer the mechanism of the coronal heating. Aims. We derive accurate power laws between EUV line intensities and the total magnetic flux in solar active regions and discuss their applications. We examine whether these global power laws are capable of providing the diagnostics of the coronal heating mechanism. Methods. This analysis is based on EUV lines recorded by the Coronal Diagnostic Spectrometer (CDS) on SOHO for 48 solar active regions, as they crossed the central meridian in years 1996-1998. Four spectral lines are used: He I 584.3 angstrom (3 x 10(4) K), OV 629.7 angstrom (2.2 x 10(5) K), Mg IX 368.06 angstrom (9.5 x 10(5) K), and Fe XVI 360.76 angstrom (2.0 x 10(6) K). In particular, the Fe XVI 360.76 angstrom line, seen only in areas of enhanced heating in active regions or bright points, has not been used before for this analysis. Results. Empirical power laws are established between the total active region intensity in the lines listed above and the total magnetic flux. We demonstrate the usefulness of some spatially integrated EUV line intensities, I-T, as a proxy for the total magnetic flux, Phi, in active regions. We point out the approximate, empirical nature of the I-T - Phi relationships and discuss the interpretation of the global power index. Different power index values for transition region and coronal lines are explained by their different dependence on pressure under the assumption of hydrostatic loop models. However, the global power laws are dominated by the size of the active regions, and we demonstrate for the first time the difficulties in uniquely relating the power index in the global I-T - Phi relationship to the power index for individual loops and comment on results obtained by other authors. We caution against using global power laws to infer the coronal heating mechanism without a detailed knowledge of the distributions of the magnetic flux densities and instrumental response as a function of temperature. Despite these uncertainties, we show that the intensities of the transition region lines in individual loops depend on the photospheric magnetic flux density, phi, through I-tr proportional to phi(delta t), delta(t) < 1, and the coronal line Fe XVI, I-Fe proportional to phi(delta c), delta(c) > 1, and under the assumption of hydrostatic loops we can place a constraint on the coronal heating models, obtaining the volumetric heating rate, E-H (erg cm(-3) s(-1)), E-H proportional to phi(gamma), where 0.6 < gamma < 1.1. C1 [Fludra, A.] Space Sci & Technol Dept, Rutherford Appleton Lab, STFC, Didcot OX11 0QX, Oxon, England. [Ireland, J.] NASA, Goddard Space Flight Ctr, ADNET, Greenbelt, MD 20771 USA. RP Fludra, A (reprint author), Space Sci & Technol Dept, Rutherford Appleton Lab, STFC, Didcot OX11 0QX, Oxon, England. EM A.Fludra@rl.ac.uk; Jack.Ireland@nasa.gov NR 31 TC 15 Z9 15 U1 0 U2 2 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 1432-0746 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAY PY 2008 VL 483 IS 2 BP 609 EP 621 DI 10.1051/0004-6361:20078183 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 299EB UT WOS:000255737500028 ER PT J AU Richard, DT Davis, SS AF Richard, D. T. Davis, S. S. TI Lunar dust characterization by polarimetric signature SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE moon; scattering; polarization ID SURFACE IMAGING POLARIMETRY; NEGATIVE POLARIZATION; SCATTERING; GRAINS; LIGHT; PARTICLES; SIZE AB Context. In support of NASA's exploration program and the return to the Moon, the polarimetric signature of dispersed individual Lunar regolith dust grains is studied to enable the characterization of the dust exopsheric environment by remote, in-situ, and standooff sensing. Aims. We explore the value of the negative polarization branch (NPB) as a signature for characterizing individual grains to determine if it can be used in the same way as for surfaces of planets and atmosphereless bodies. Methods. The linear polarization phase curve for single spheres of silicate and for aggregates of spherical silicate grains of different porosity are computed using the discrete dipole approximation (DDA) for a range of grain sizes. Features in these curves are identified and their evolution explored as a function of grain size and aggregate porosity. We focus particularly on the so-called negative polarization branch that has been historically used to characterize planetary surfaces. Results. Calculations show that polarization phase curves for spherical grains exhibit a sharp transition over a narrow range of size parameter between two distinct regimes, one typical of Rayleigh scattering and another dominated by a large NPB. The linear polarimetric signature observed for aggregates is a composite of a) the polarization induced by individual grains composing the aggregate and b) the polarization due to the aggregate as a whole dust grain. The weight of each component varies depending on the porosity of the aggregate. An NPB similar to the one observed for atmosphereless astronomical bodies is present for different ranges of the size parameter depending on the value of the porosity. It appears as a remnant of the negative branch exhibited by the single spherical grains. The sharper, narrow negative branch that is measured for some granular surfaces in the laboratory or seen in astronomical observations is not observed here. Conclusions. These results suggest that the wide negative branch is due to the scattering by individual grains and single aggregates, while the narrow negative branch is more likely due to coherent backscattering or shadowing effects in bulk material. The shape and evolution of the NPB could be used to characterize spherical grains and to differentiate between aggregates with the same porosity but different sizes, but does not appear to be a practical candidate for univocally differentiating between aggregates of different porosity. C1 [Richard, D. T.; Davis, S. S.] NASA, Ames Res Ctr, Space Sci & Astrobiol Div, Lunar Dust Lab, Moffett Field, CA 94035 USA. [Richard, D. T.] San Jose State Univ, Res Fdn, San Jose, CA 95112 USA. RP Richard, DT (reprint author), NASA, Ames Res Ctr, Space Sci & Astrobiol Div, Lunar Dust Lab, MS 245-3, Moffett Field, CA 94035 USA. EM Denis.T.Richard@nasa.gov; Sanford.S.Davis@nasa.gov NR 32 TC 4 Z9 4 U1 0 U2 2 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAY PY 2008 VL 483 IS 2 BP 643 EP 649 DI 10.1051/0004-6361:20079108 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 299EB UT WOS:000255737500031 ER PT J AU Pitman, KM Hofmeister, AM Corman, AB Speck, AK AF Pitman, K. M. Hofmeister, A. M. Corman, A. B. Speck, A. K. TI Optical properties of silicon carbide for astrophysical applications - I. New laboratory infrared reflectance spectra and optical constants SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE methods : laboratory; stars : carbon; stars : circumstellar matter; ISM : dust; extinction ID CIRCUMSTELLAR DUST SHELLS; CARBON STARS; SIC POLYTYPES; C-STARS; MAGELLANIC-CLOUD; AGB STARS; CONDENSATION SEQUENCE; INTERSTELLAR-MEDIUM; PLANETARY-NEBULAE; SIZE DISTRIBUTION AB Aims. The SiC optical constants are fundamental inputs for radiative transfer (RT) models of astrophysical dust environments. However, previously published values contain errors and do not adequately represent the bulk physical properties of the cubic (beta) SiC polytype usually found around carbon stars. We provide new, uncompromised optical constants for beta- and alpha-SiC derived from single-crystal reflectance spectra and investigate quantitatively (i) whether there is any difference between alpha- and beta-SiC that can be seen in infrared (IR) spectra and optical functions and (ii) whether weak features from lambda similar to 12.5-13.0 mu m need to be fitted. Methods. We measured mid- and far-IR reflectance spectra for two samples of 3C (beta-) SiC and four samples of 6H (alpha-) SiC. For the latter group, we acquired polarized data (E perpendicular to c, E parallel to c orientations). We calculated the real and imaginary parts of the complex refractive index (n(lambda) + ik(lambda)) and the ideal absorption coefficients via classical dispersion fits to our reflectance spectra. Results. We find that beta-SiC and E perpendicular to c alpha-SiC have almost identical optical functions but that n(lambda) and k(lambda) for E parallel to c alpha-SiC are shifted to lower frequency. Peak positions determined for both 3C (beta-) and 6H (alpha-) SiC polytypes agree with Raman measurements and show that a systematic error of 4 cm(-1) exists in previously published IR analyses, attributable to inadequate resolution of older instruments for the steep, sharp modes of SiC. Weak modes are present for samples with impurities. Our calculated absorption coefficients are much higher than laboratory measurements. Whereas astrophysical dust grain sizes remain fairly unconstrained, SiC grains larger than about 1 mu m in diameter will be opaque at frequencies near the peak center. Conclusions. Previous optical constants for SiC do not reflect the true bulk properties, and they are only valid for a narrow grain size range. The new optical constants presented here will allow narrow constraints to be placed on the grain size and shape distribution that dominate in astrophysical environments. C1 [Pitman, K. M.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Pitman, K. M.; Hofmeister, A. M.] Washington Univ, Dept Earth & Planetary Sci, St Louis, MO 63130 USA. [Corman, A. B.; Speck, A. K.] Univ Missouri, Dept Phys & Astron, Columbia, MO 65211 USA. RP Pitman, KM (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Karly.M.Pitman@jpl.nasa.gov; hofmeist@levee.wustl.edu; abcp68@mizzou.edu; speckan@missouri.edu NR 95 TC 38 Z9 38 U1 1 U2 16 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAY PY 2008 VL 483 IS 2 BP 661 EP 672 DI 10.1051/0004-6361:20078468 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 299EB UT WOS:000255737500033 ER PT J AU Nordon, R Behar, E AF Nordon, R. Behar, E. TI Abundance variations and first ionization potential trends during large stellar flares SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE stars : activity; stars : coronae; stars : flare; stars : abundances; X-rays : stars ID X-RAY FLARE; LOW-MASS STARS; CORONAL ABUNDANCES; XMM-NEWTON; CHROMOSPHERIC EVAPORATION; EXTREME-ULTRAVIOLET; PROXIMA-CENTAURI; PHOTOSPHERIC ABUNDANCES; ELEMENTAL ABUNDANCES; RATE COEFFICIENTS AB Context. In the solar corona, elements of low first ionization potential (FIP less than or similar to 10 eV) are enriched relative to their abundances in the photosphere, while high-FIP abundances remain unchanged. This was labeled as the Solar FIP effect. High-resolution X-ray spectroscopy has revealed that active stellar coronae show an opposite effect, which was labeled the inverse-FIP (IFIP) effect. The correlation found between coronal activity and the FIP/IFIP bias suggests that flaring activity is involved in switching from FIP to IFIP. Aims. This work aims at a more systematic understanding of the FIP trends during stellar flares and complements an earlier study based on Chandra alone. Methods. The eight brightest X-ray flares observed with XMM-Newton are analyzed and compared with their respective quiescence states. Together with six previous flares observed with Chandra, this establishes the best currently available sample of flares. We look for abundance variations during the flare and their correlation with FIP. For that purpose, we define a new FIP bias measure. Results. A trend is found where coronae that are IFIP-biased in quiescence, show a FIP bias during flares relative to their quiescence composition. This effect is reversed for coronae that are FIP-biased in quiescence. The observed trend is thus consistent with chromospheric evaporation rather than with a FIP mechanism operating during flares. It also suggests that the quiescent IFIP bias is real and that the large flares are not the direct cause of the IFIP effect in stellar coronae. C1 [Nordon, R.; Behar, E.] Technion Israel Inst Technol, Dept Phys, IL-32000 Haifa, Israel. [Behar, E.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Nordon, R (reprint author), Technion Israel Inst Technol, Dept Phys, IL-32000 Haifa, Israel. EM nordon@physics.technion.ac.il; behar@physics.technion.ac.il NR 58 TC 15 Z9 15 U1 0 U2 1 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAY PY 2008 VL 482 IS 2 BP 639 EP 651 DI 10.1051/0004-6361:20078848 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 290XE UT WOS:000255156100026 ER PT J AU Walker, GAH Croll, B Matthews, JM Kuschnig, R Huber, D Weiss, WW Shkolnik, E Rucinski, SM Guenther, DB Moffat, AFJ Sasselov, D AF Walker, G. A. H. Croll, B. Matthews, J. M. Kuschnig, R. Huber, D. Weiss, W. W. Shkolnik, E. Rucinski, S. M. Guenther, D. B. Moffat, A. F. J. Sasselov, D. TI MOST detects variability on tau Bootis A possibly induced by its planetary companion SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE stars : activity; stars : individual : tau Boo; stars : early-type; stars : starspots; stars : rotation; stars : planetary systems ID EXTRASOLAR GIANT PLANETS; SUN-LIKE STARS; CHROMOSPHERIC ACTIVITY; HOT JUPITERS; 51 PEGASI; PHOTOMETRY; HD-192263; SPECTRUM; SPACE AB Context. There is considerable interest in the possible interaction between parent stars and giant planetary companions in 51 Peg-type systems. Aims. We shall demonstrate from MOST satellite photometry and Ca II K line emission that there has been a persistent, variable region on the surface of tau Boo A, which tracked its giant planetary companion for some 440 planetary revolutions and lies similar to 68 degrees. (phi = 0.8) in advance of the sub-planetary point. Methods. The light curves are folded on a range of periods centered on the planetary orbital period, and phase-dependent variability is quantified by Fourier methods and by the mean absolute deviation (MAD) of the folded data for both the photometry and the Ca II K line reversals. Results. The region varies in brightness on the time scale of a rotation by similar to 1 mmag. In 2004 it resembled a dark spot of variable depth, while in 2005 it varied between bright and dark. The 2004 light curve gives a spot rotation period of 3.5 +/- 0.7 d compared to the known planetary orbital period of 3.3125 d. The amplitude spectrum of the 2005 light curve shows no marked peak at the orbital period but the mean absolute deviation (MAD) of the light curve has a well-defined maximum (half width similar to 0.15 d) centered on the orbital frequency. Over the 123 planetary orbits spanned by the photometry, the variable region detected in 2004 and in 2005 are synchronized to the planetary orbital period within 0.0015 d. The Ca II K line in 2001, 2002, and 2003 also shows enhanced K-line variability centered on phi = 0.8, extending coverage to some 440 planetary revolutions. Conclusions. The apparently constant rotation period of the variable region and its rapid variation make an explanation in terms of conventional star spots unlikely. The lack of complementary variability at phi = 0.3 and the detection of the variable region so far in advance of the sub-planetary point excludes tidal excitation, but the combined photometric and Ca II K line reversal results make a good case for an active region induced magnetically on the surface of tau Boo A by its planetary companion. C1 [Croll, B.] Univ Toronto, Dept Astron & Astrophys, Toronto, ON M5S 3H4, Canada. [Matthews, J. M.] Univ British Columbia, Dept Phys & Astron, Vancouver, BC V6T 1Z1, Canada. [Kuschnig, R.; Huber, D.; Weiss, W. W.] Univ Vienna, Inst Astron, A-1180 Vienna, Austria. [Shkolnik, E.] Univ Hawaii, NASA, Astrobiol Inst, Manoa, HI USA. [Rucinski, S. M.] Univ Toronto, David Dunlap Observ, Dept Astron & Astrophys, Richmond Hill, ON L4C 4Y6, Canada. [Guenther, D. B.] St Marys Univ, Dept Phys & Astron, Halifax, NS B3H 3C3, Canada. [Moffat, A. F. J.] Univ Montreal, Dept Phys, Montreal, PQ H3C 3J7, Canada. [Moffat, A. F. J.] Obs Mont Megant, Montreal, PQ, Canada. [Sasselov, D.] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Walker, GAH (reprint author), 1234 Hewlett Pl, Victoria, BC V8S 4P7, Canada. EM gordonwa@uvic.ca NR 29 TC 51 Z9 51 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAY PY 2008 VL 482 IS 2 BP 691 EP 697 DI 10.1051/0004-6361:20078952 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 290XE UT WOS:000255156100032 ER PT J AU Ofman, L Wang, TJ AF Ofman, L. Wang, T. J. TI Hinode observations of transverse waves with flows in coronal loops SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE sun : flares; sun : corona; sun : magnetic fields; sun : oscillations; waves ID MODE KINK OSCILLATIONS; ALFVEN WAVES; VERTICAL OSCILLATIONS; NUMERICAL SIMULATIONS; MAGNETIC-FIELD; TRACE; SEISMOLOGY; REGION; SUMER AB Aims. We report the first evidence for transverse waves in coronal multithreaded loops with cool plasma ejected from the chromosphere flowing along the threads. These observations are good candidates for coronal seismology. Methods. We analyzed observations made with Solar Optical Telescope ( SOT) on board the Hinode satellite in the Ca II H line filter. Results. The oscillations are visible for about 3 periods, with a period lasting about 2 min, with weak damping. We see the oscillations in thin threads (similar to 0.5 '') of cool plasma flowing in the coronal loops with speeds in the range 74-123 km s(-1). Conclusions. Observations indicate that the waves exhibit different properties in the various threads. In some threads, the waves are nearly standing fundamental kink modes with a phase speed of about 1250 km s(-1), whereas the dynamics of other threads is consistent with propagating fast magnetosonic waves. Based on the observed wave and loop properties and the assumed active region loop density in the range ( 1-5) x 10(9) cm(-3), the estimated energy flux is sufficient to heat the loops to coronal temperatures, and the average magnetic field in the threads is estimated as 20 +/- 7 G. C1 Catholic Univ Amer, Dept Phys, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Ofman, L (reprint author), Catholic Univ Amer, Dept Phys, Code 671, Greenbelt, MD 20771 USA. EM ofman@waves.gsfc.nasa.gov NR 33 TC 91 Z9 91 U1 0 U2 1 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAY PY 2008 VL 482 IS 2 BP L9 EP L12 DI 10.1051/0004-6361:20079340 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 290XE UT WOS:000255156100003 ER PT J AU Hamilton, TS Casertano, S Turnshek, DA AF Hamilton, Timothy S. Casertano, Stefano Turnshek, David A. TI The fundamental plane of QSOs and the relationship between host and nucleus SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; galaxies : fundamental parameters; quasars : general ID BLACK-HOLE MASS; BAND ENERGY-DISTRIBUTION; ACTIVE GALACTIC NUCLEI; ROSAT DETECTED QUASARS; RADIO-LOUD QUASARS; ELLIPTIC GALAXIES; BULGE MASS; VELOCITY DISPERSION; STELLAR OBJECTS; COMPLETE SAMPLE AB We present results from an archival study of 70 medium- redshift QSOs observed with HST's WFPC2. The QSOs have magnitudes M-V <= - 23 ( total nuclear plus host light) and redshifts 0: 06 <= z <= 0: 46. The aim of the present study is to investigate the connections between the nuclear and host properties of QSOs, using high- resolution images and removing the central point source to reveal the host structure. We confirm that more luminous QSO nuclei are found in more luminous host galaxies. Using central black hole masses from the literature, we find that nuclear luminosity also generally increases with black hole mass, but it is not tightly correlated. Nuclear luminosities range from 2.3% to 200% of the Eddington limit. Those in elliptical hosts cover the range fairly evenly, while those in spirals are clustered near the Eddington limit. Using a principal components analysis, we find a kind of fundamental plane relating the nuclear luminosity to the size and effective surface magnitude of the bulge. Using optical nuclear luminosity, this relationship explains 96.1% of the variance in the overall sample, while another version of the relationship uses X- ray nuclear luminosity and explains 95.2% of the variance. The form of this QSO fundamental plane shows similarities to the well-studied fundamental plane of elliptical galaxies, and we examine the possible relationship between them, as well as the difficulties involved in establishing this connection. C1 [Hamilton, Timothy S.; Turnshek, David A.] Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. [Hamilton, Timothy S.; Casertano, Stefano] Space Telescope Sci Inst, Baltimore, MD 21218 USA. [Hamilton, Timothy S.] NASA, GSFC, Natl Res Council Assoc, Washington, DC USA. RP Hamilton, TS (reprint author), Shawnee State Univ, Dept Nat Sci, Portsmouth, OH 45662 USA. EM thamilton@shawnee.edu; stefano@stsci.edu; turnshek@pitt.edu OI Hamilton, Timothy/0000-0002-9753-1769 NR 67 TC 13 Z9 13 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 1 PY 2008 VL 678 IS 1 BP 22 EP 40 DI 10.1086/524182 PG 19 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 294BE UT WOS:000255378300003 ER PT J AU Gliozzi, M Papadakis, IE Sambruna, RM AF Gliozzi, M. Papadakis, I. E. Sambruna, R. M. TI Long-term X-ray monitoring of NGC 6251: Evidence for a jet-dominated radio galaxy SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; galaxies : jets; galaxies : nuclei; X-rays : galaxies ID ACTIVE GALACTIC NUCLEI; PROPORTIONAL COUNTER ARRAY; BL LACERTAE OBJECT; TIMING-EXPLORER; FR-I; BLAZAR MARKARIAN-421; SEYFERT-1 GALAXIES; SPECTRAL EVOLUTION; TEV VARIABILITY; EMISSION AB We present the first X- ray monitoring observations of the X- ray-bright FR I radio galaxy NGC 6251 observed with RXTE for 1 yr. The primary goal of this study is to shed light on the origin of the X- rays by investigating the spectral variability with model- independent methods coupled with time- resolved and flux- selected spectroscopy. The main results can be summarized as follows: ( 1) Throughout the monitoring campaign, NGC 6251 was in relatively high- flux state with an average 2-10 keV absorbed flux of the order of 4: 5; 10(-12) erg cm(-2) s(-1) and a corresponding intrinsic luminosity of 6; 10(42) erg s(-1). ( 2) The flux persistently changed with fluctuations of the order of similar to 2 on timescales of 20-30 days. ( 3) When the hardness ratio is plotted against the average count rate, there is evidence for a spectral hardening as the source brightens; this finding is confirmed by a flux- selected spectral analysis. ( 4) The fractional variability appears to be more pronounced in the hard energy band ( 5-12 keV) than in the soft one ( 2.5-5 keV). ( 5) Two month averaged and flux- limited energy spectra are adequately fitted by a power law. A Fe K alpha line is never statistically required, although the presence of a strong iron line cannot be ruled out, due to the high upper limits on the line equivalent width. The inconsistency of the spectral variability behavior of NGC 6251 with the typical trend observed in Seyfert galaxies and the similarity with blazars lend support to a jet- dominated scenario during the RXTE monitoring campaign. However, a possible contribution from a disk- corona system cannot be ruled out. C1 [Gliozzi, M.] George Mason Univ, Fairfax, VA 22030 USA. [Papadakis, I. E.] Univ Crete, Dept Phys, Iraklion 71003, Crete, Greece. [Sambruna, R. M.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Gliozzi, M (reprint author), George Mason Univ, 4400 Univ Dr, Fairfax, VA 22030 USA. RI Papadakis, Iossif/C-3235-2011 NR 49 TC 3 Z9 3 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 1 PY 2008 VL 678 IS 1 BP 78 EP 86 DI 10.1086/529540 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 294BE UT WOS:000255378300006 ER PT J AU Katsuda, S Mori, K Tsunemi, H Park, S Hwang, U Burrows, DN Hughes, JP Slane, PO AF Katsuda, S. Mori, K. Tsunemi, H. Park, S. Hwang, U. Burrows, D. N. Hughes, J. P. Slane, P. O. TI Discovery of fast-moving X-ray-emitting ejecta knots in the oxygen-rich supernova remnant Puppis A SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : abundances; ISM : individual (Puppis A); supernova remnants; X-rays : ISM ID NEUTRON-STAR KICKS; CASSIOPEIA-A; NOVA REMNANT; NUCLEOSYNTHESIS; INHOMOGENEITIES; SPECTROSCOPY; ABUNDANCES; EMISSION AB We report on the discovery of fast- moving X- ray-emitting ejecta knots in the Galactic oxygen- rich supernova remnant Puppis A from XMM- Newton observations. We find an X- ray knotty feature positionally coincident with an O- rich fast- moving optical filament with blueshifted line emission located in the northeast of Puppis A. We extract spectra from northern and southern regions of the feature. Applying a one- component nonequilibrium ionization model for the two spectra, we find high metal abundances relative to the solar values in both spectra. This fact clearly shows that the feature originates from metal- rich ejecta. In addition, we find that line emission in the two regions is blueshifted. The Doppler velocities derived in the two regions are different with each other, suggesting that the knotty feature consists of two knots that are close to each other along the line of sight. Since fast- moving O- rich optical knots/ filaments are believed to be recoiled metal- rich ejecta, expelled to the opposite direction against the high- velocity central compact object, we propose that the ejecta knots disclosed here are also part of the recoiled material. C1 [Katsuda, S.; Tsunemi, H.] Osaka Univ, Dept Earth & Space Sci, Grad Sch Sci, Osaka 600043, Japan. [Mori, K.] Miyazaki Univ, Fac Engn, Dept Appl Phys, Miyazaki 8892192, Japan. [Park, S.; Burrows, D. N.] Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. [Hwang, U.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Hwang, U.] Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. [Hughes, J. P.] Rutgers State Univ, Dept Phys & Astron, Piscataway, NJ 08854 USA. [Slane, P. O.] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Katsuda, S (reprint author), Osaka Univ, Dept Earth & Space Sci, Grad Sch Sci, 1-1 Machikaneyama, Osaka 600043, Japan. EM katsuda@ess.sci.osaka-u.ac.jp NR 36 TC 17 Z9 17 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 1 PY 2008 VL 678 IS 1 BP 297 EP 302 DI 10.1086/586891 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 294BE UT WOS:000255378300025 ER PT J AU Bauschlicher, CW Peeters, E Allamandola, LJ AF Bauschlicher, Charles W. Peeters, Els Allamandola, Louis J. TI The infrared spectra of very large, compact, highly symmetric, polycyclic aromatic hydrocarbons (PAHs) SO ASTROPHYSICAL JOURNAL LA English DT Article DE astrochemistry; infrared : ISM; ISM : lines and bands; ISM : molecules; line : identification; molecular data; techniques : spectroscopic ID MIDINFRARED SPECTRA; REFLECTION NEBULAE; EMISSION-SPECTRA; INTERSTELLAR DUST; LARGE MOLECULES; HII-REGIONS; MODEL; SPECTROSCOPY; BANDS; EXCITATION AB The mid-infrared spectra of large PAHs ranging from C54H18 to C130H28 are determined computationally using density functional theory. Trends in the band positions and intensities as a function of PAH size, charge, and geometry are discussed. Regarding the 3.3, 6.3, and 11.2 mu m bands similar conclusions hold as with small PAHs. This does not hold for the other features. The larger PAH cations and anions produce bands at 7.8 mu m and, as PAH sizes increases, a band near 8.5 mu m becomes prominent and shifts slightly to the red. In addition, the average anion peak falls slightly to the red of the average cation peak. The similarity in behavior of the 7.8 and 8.6 mu m bands with the astronomical observations suggests that they arise from large, cationic and anionic PAHs, with the specific peak position and profile reflecting the PAH cation to anion concentration ratio and relative intensities of PAH size. Hence, the broad astronomical 7.7 mu m band is produced by a mixture of small and large PAH cations and anions, with small and large PAHs contributing more to the 7.6 and 7.8 mu m components, respectively. For the CH out-of-plane vibrations, the duo hydrogens couple with the solo vibrations and produce bands that fall at wavelengths slightly different than their counterparts in smaller PAHs. As a consequence, previously deduced PAH structures are altered in favor of more compact and symmetric forms. In addition, the overlap between the duo and trio bands may reproduce the blue-shaded 12.8 mu m profile. C1 [Bauschlicher, Charles W.] NASA, Ames Res Ctr, Space Technol Div, Moffett Field, CA 94035 USA. [Peeters, Els] Univ Western Ontario, Dept Phys & Astron, London, ON N6A 3K7, Canada. [Peeters, Els] SETI Inst, Mountain View, CA 94043 USA. [Peeters, Els; Allamandola, Louis J.] NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. RP Bauschlicher, CW (reprint author), NASA, Ames Res Ctr, Space Technol Div, Mail Stop 230-3, Moffett Field, CA 94035 USA. EM charles.w.bauschlicher@nasa.gov; epeeters@uwo.ca; louis.j.allamandola@nasa.gov NR 47 TC 87 Z9 87 U1 1 U2 24 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 1 PY 2008 VL 678 IS 1 BP 316 EP 327 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 294BE UT WOS:000255378300028 ER PT J AU Reimer, TW Welsh, WF Mukai, K Ringwald, FA AF Reimer, Tamara W. Welsh, William F. Mukai, Koji Ringwald, F. A. TI The intermediate polar EI UMa: A prepolar cataclysmic variable SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; novae, cataclysmic variables; stars : dwarf novae; stars : individual (EI UMa) ID SECONDARY PHOTOMETRIC STANDARDS; RAY OBSERVATIONS; YY DRACONIS; DWARF NOVAE; OUTBURST; OBJECTS; STARS; INSTABILITIES; EVOLUTION; BINARIES AB We present optical and X-ray time series photometry of EI UMa that reveal modulation at 746 and 770 s, which we interpret as the white dwarf spin and spin-orbit sidebands. These detections, combined with previous X-ray studies, establish EI UMa as an intermediate polar. We estimate the mass accretion rate to be similar to 3.6 x 10(17) g s(-1), which is close to, and likely greater than, the critical rate above which dwarf nova instabilities are suppressed. We also estimate the white dwarf to have a large magnetic moment mu > (3.4 +/- 0.2); 10(33) G cm(3). The high mass accretion rate and magnetic moment imply the existence of an accretion ring rather than a disk, and along with the relatively long orbital period, these suggest that EI UMa is a rare example of a prepolar cataclysmic variable. C1 [Reimer, Tamara W.; Welsh, William F.] San Diego State Univ, Dept Astron, San Diego, CA 92182 USA. [Mukai, Koji] Univ Maryland, Astrophys Sci Div, Baltimore, MD 21201 USA. [Mukai, Koji] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Ringwald, F. A.] Calif State Univ Fresno, Dept Phys, Fresno, CA 93740 USA. RP Reimer, TW (reprint author), San Diego State Univ, Dept Astron, 5500 Campanile Dr, San Diego, CA 92182 USA. EM tamara.reimer@gmail.com; wfw@sciences.sdsu.edu; mukai@milkyway.gsfc.nasa.gov; ringwald@csufresno.edu NR 44 TC 8 Z9 8 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 1 PY 2008 VL 678 IS 1 BP 376 EP 384 DI 10.1086/587043 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 294BE UT WOS:000255378300034 ER PT J AU Drake, JJ Ercolano, B Swartz, DA AF Drake, Jeremy J. Ercolano, Barbara Swartz, Douglas A. TI X-ray-fluorescent FeK alpha lines from stellar photospheres SO ASTROPHYSICAL JOURNAL LA English DT Article DE radiation mechanisms : nonthermal; stars : coronae; Sun : corona; Sun : X-rays, gamma rays; techniques : spectroscopic; X-rays : stars ID PHOTOIONIZATION CROSS-SECTIONS; SOLAR-FLARE; IRON-LINE; EMISSION-LINES; BLACK-HOLE; CHANDRA OBSERVATION; STRONG GRAVITY; COLD MATTER; SPECTRA; OBJECTS AB X-ray spectra from stellar coronae are reprocessed by the underlying photosphere through scattering and photoionization events. While reprocessed X-ray spectra reaching a distant observer are at a flux level of only a few percent of that of the corona itself, characteristic lines formed by inner shell photoionization of some abundant elements can be significantly stronger. The emergent photospheric spectra are sensitive to the distance and location of the fluorescing radiation and can provide diagnostics of coronal geometry and abundance. Here we present Monte Carlo simulations of the photospheric K-alpha 1,(alpha 2) doublet arising from quasi-neutral Fe irradiated by a coronal X-ray source. Fluorescent line strengths have been computed as a function of the height of the radiation source, the temperature of the ionizing X-ray spectrum, and the viewing angle. We also illustrate how the fluorescence efficiencies scale with the photospheric metallicity and the Fe abundance. Based on the results we make three comments: (1) fluorescent Fe lines seen from pre-main-sequence stars mostly suggest flared disk geometries and/or supersolar disk Fe abundances; (2) the extreme approximate to 1400 m angstrom line observed from a flare on V1486 Ori could be explained entirely by X-ray fluorescence if the flare itself were partially eclipsed by the limb of the star; and (3) the fluorescent Fe line detected by Swift during a large flare on II Peg is consistent with X-ray excitation and does not require a collisional ionization contribution. There is no convincing evidence supporting the energetically challenging explanation of electron impact excitation for observed stellar FeK alpha lines. C1 [Drake, Jeremy J.; Ercolano, Barbara] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. [Swartz, Douglas A.] NASA, George C Marshall Space Flight Ctr, Univ Space Res Assoc, Huntsville, AL 35812 USA. RP Drake, JJ (reprint author), Harvard Smithsonian Ctr Astrophys, MS-3,60 Garden St, Cambridge, MA 02138 USA. NR 58 TC 17 Z9 17 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD MAY 1 PY 2008 VL 678 IS 1 BP 385 EP 393 DI 10.1086/524976 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 294BE UT WOS:000255378300035 ER PT J AU Bowen, DV Jenkins, EB Tripp, TM Sembach, KR Savage, BD Moos, HW Oegerle, WR Friedman, SD Gry, C Kruk, JW Murphy, E Sankrit, R Shull, JM Sonneborn, G York, DG AF Bowen, David V. Jenkins, Edward B. Tripp, Todd M. Sembach, Kenneth R. Savage, Blair D. Moos, H. Warren Oegerle, William R. Friedman, Scott D. Gry, Cecile Kruk, Jeffrey W. Murphy, Edward Sankrit, Ravi Shull, J. Michael Sonneborn, George York, Donald G. TI The Far Ultraviolet Spectroscopic Explorer survey of OVI absorption in the disk of the milky way SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Review DE Galaxy : disk; ISM : clouds; ISM : kinematics and dynamics; ISM : structure; ultraviolet : ISM ID HIGHLY IONIZED-GAS; X-RAY-EMISSION; VELA SUPERNOVA REMNANT; EARLY-TYPE STARS; LOCAL INTERSTELLAR-MEDIUM; O-VI ABSORPTION; ALL-SKY SURVEY; TELESCOPE IMAGING SPECTROGRAPH; INTER-STELLAR MEDIUM; B-TYPE STARS AB To probe the distribution and physical characteristics of interstellar gas at temperatures T approximate to 3 x 10(5) K in the disk of the MilkyWay, we have used the Far Ultraviolet Spectroscopic Explorer (FUSE) to observe absorption lines of O vi lambda 1032 toward 148 early-type stars situated at distances > 1 kpc. After subtracting off a mild excess of O VI arising from the Local Bubble, combining our new results with earlier surveys of O VI, and eliminating stars that show conspicuous localized X-ray emission, we find an average O VI midplane density n(0) 1.3 x 10(-8) cm(-3). The density decreases away from the plane of the Galaxy in a way that is consistent with an exponential scale height of 3.2 kpc at negative latitudes or 4.6 kpc at positive latitudes. Average volume densities of O VI along different sight lines exhibit a dispersion of about 0.26 dex, irrespective of the distances to the target stars. This indicates that O VI does not arise in randomly situated clouds of a fixed size and density, but instead is distributed in regions that have a very broad range of column densities, with the more strongly absorbing clouds having a lower space density. Line widths and centroid velocities are much larger than those expected from differential Galactic rotation, but they are nevertheless correlated with distance and N(O VI), which reinforces our picture of a diverse population of hot plasma regions that are ubiquitous over the entire Galactic disk. The velocity extremes of the O VI profiles show a loose correlation with those of very strong lines of less ionized species, supporting a picture of a turbulent, multiphase medium churned by shock-heated gas from multiple supernova explosions. C1 [Bowen, David V.; Jenkins, Edward B.; Tripp, Todd M.] Princeton Univ Observ, Princeton, NJ 08544 USA. [Tripp, Todd M.] Univ Massachusetts, Dept Astron, Amherst, MA 01003 USA. [Sembach, Kenneth R.; Friedman, Scott D.] Space Telescope Sci Inst, Baltimore, MD 21218 USA. [Savage, Blair D.] Univ Wisconsin, Dept Astron, Madison, WI 53706 USA. [Moos, H. Warren; Kruk, Jeffrey W.] Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. [Oegerle, William R.; Sonneborn, George] NASA, Goddard Space Flight Ctr, Astrophys Sci Div, Greenbelt, MD 20771 USA. [Savage, Blair D.] Lab Astrophys Marseille, F-13376 Marseille, France. [Murphy, Edward] Univ Virginia, Dept Astron, Charlottesville, VA 22904 USA. [Sankrit, Ravi] Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94270 USA. [Shull, J. Michael] Univ Colorado, Dept Astrophys & Planetary Sci, Boulder, CO 80309 USA. [York, Donald G.] Univ Chicago, Enrico Fermi Inst, Dept Astron & Astrophys, Chicago, IL 60637 USA. RP Bowen, DV (reprint author), Princeton Univ Observ, Peyton Hall,Ivy Lane, Princeton, NJ 08544 USA. RI Oegerle, William/C-9070-2012; Sonneborn, George/D-5255-2012; Kruk, Jeffrey/G-4047-2012; Jenkins, Edward/P-5684-2014; OI Jenkins, Edward/0000-0003-1892-4423; Murphy, Edward/0000-0003-2925-738X NR 312 TC 64 Z9 64 U1 0 U2 7 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0067-0049 EI 1538-4365 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD MAY PY 2008 VL 176 IS 1 BP 59 EP 163 DI 10.1086/524773 PG 105 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 326PT UT WOS:000257672100004 ER PT J AU van Belle, GT van Belle, G Creech-Eakman, MJ Coyne, J Boden, AF Akeson, RL Ciardi, DR Rykoski, KM Thompson, RR Lane, BF AF van Belle, G. T. van Belle, G. Creech-Eakman, M. J. Coyne, J. Boden, A. F. Akeson, R. L. Ciardi, D. R. Rykoski, K. M. Thompson, R. R. Lane, B. F. CA PTI Collaboration TI The Palomar Testbed Interferometer calibrator catalog SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Review DE binaries : general; catalogs; infrared : stars; instrumentation : high angular resolution instrumentation : interferometers; stars : fundamental parameters; stars : imaging; techniques : high angular resolution; techniques : interferometric ID H-BETA-PHOTOMETRY; NORTH-GALACTIC POLE; F-TYPE STARS; A-TYPE STARS; ICCD SPECKLE OBSERVATIONS; PROPER-MOTION STARS; METAL-POOR STARS; LATITUDE MOLECULAR CLOUDS; RADIAL-VELOCITY SURVEY; LARGE MAGELLANIC CLOUD AB The Palomar Testbed Interferometer (PTI) archive of observations between 1998 and 2005 is examined for objects appropriate for calibration of optical long-baseline interferometer observations -stars that are predictably pointlike and single. Approximately 1400 nights of data on 1800 objects were examined for this investigation. We compare those observations to an intensively studied object that is a suitable calibrator, HD 217014, and statistically compare each candidate calibrator to that object by computing both a Mahalanobis distance and a principal component analysis. Our hypothesis is that the frequency distribution of visibility data associated with calibrator stars differs from noncalibrator stars such as binary stars. Spectroscopic binaries resolved by PTI, objects known to be unsuitable for calibrator use, are similarly tested to establish detection limits of this approach. From this investigation, we find more than 350 observed stars suitable for use as calibrators (with an additional approximate to 140 being rejected), corresponding to k95% sky coverage for PTI. This approach is noteworthy in that it rigorously establishes calibration sources through a traceable, empirical methodology, leveraging the predictions of spectral energy distribution modeling but also verifying it with the rich body of PTI's on-sky observations. C1 [van Belle, G. T.; Boden, A. F.; Akeson, R. L.; Ciardi, D. R.; Rykoski, K. M.; Thompson, R. R.; PTI Collaboration] CALTECH, Michelson Sci Ctr, Pasadena, CA 91125 USA. [van Belle, G.] Univ Washington, Dept Biostat, Seattle, WA 98195 USA. [Creech-Eakman, M. J.] New Mexico Inst Min & Technol, Socorro, NM 87801 USA. [Coyne, J.] Univ Cambridge, Cambridge, England. [Lane, B. F.] MIT, Cambridge, MA 02139 USA. [PTI Collaboration] Jet Prop Lab, Pasadena, CA USA. RP van Belle, GT (reprint author), CALTECH, Michelson Sci Ctr, Pasadena, CA 91125 USA. EM gerard@ipac.caltech.edu; vanbelle@u.washington.edu; mce@kestrel.nmt.edu; jc466@cam.ac.uk; bode@ipac.caltech.edu; akeson@ipac.caltech.edu; ciardi@ipac.caltech.edu; kmr@ipac.caltech.edu; thompson@ipac.caltech.edu; blane@mit.edu OI Ciardi, David/0000-0002-5741-3047 NR 360 TC 42 Z9 42 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD MAY PY 2008 VL 176 IS 1 BP 276 EP 292 DI 10.1086/526548 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 326PT UT WOS:000257672100010 ER PT J AU Streets, DG Yu, C Wu, Y Chin, M Zhao, Z Hayasaka, T Shi, G AF Streets, David G. Yu, Carolyne Wu, Ye Chin, Mian Zhao, Zongci Hayasaka, Tadahiro Shi, Guangyu TI Aerosol trends over China, 1980-2000 SO ATMOSPHERIC RESEARCH LA English DT Article DE aerosols; China; solar radiation; climate change ID EMISSIONS; ASIA; TEMPERATURE; POLLUTION; DIOXIDE; MODEL; SO2; NOX AB Annual emission trends of sulfur dioxide, black carbon, and organic carbon are presented for East Asia for the period 1980-2000. Emissions of sulfur dioxide peaked in about 1996, and emissions of the carbonaceous aerosols peaked in about 1994-1995, due to a variety of economic, environmental, and social forces. These emissions are converted to their contributions to aerosol optical depth (AOD) over East Asia, using regional results from the GOCART global chemical transport model. We calculate that, on average, AOD over China rose from a value of 0.25 in 1980, peaked at a value of about 0.305 in 1995-1996, and then decreased to about 0.29 in 2000. This trend is consistent with surface shortwave irradiance measurements at 52 weather stations in China, as well as with other radiation-related trends. It may also be consistent with a rise in mean surface temperatures in China starting about the middle of the 1990s. (c) 2007 Elsevier B.V. All rights reserved. C1 [Streets, David G.; Yu, Carolyne] Argonne Natl Lab, Dept Informat & Decis Sci, Argonne, IL 60439 USA. [Wu, Ye] Argonne Natl Lab, Div Energy Syst, Argonne, IL 60439 USA. [Chin, Mian] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Zhao, Zongci] China Meteorolog Adm, Natl Climate Ctr, Beijing 100871, Peoples R China. [Hayasaka, Tadahiro] Natl Inst Humanities, Res Inst Humanity & Nat, Kita Ku, Kyoto 6038047, Japan. [Shi, Guangyu] Chinese Acad Sci, Inst Atmospher Phys, Beijing 100029, Peoples R China. RP Streets, DG (reprint author), Argonne Natl Lab, Dept Informat & Decis Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. EM dstreets@anl.gov RI Chin, Mian/J-8354-2012; Wu, Ye/O-9779-2015; OI Streets, David/0000-0002-0223-1350 NR 41 TC 94 Z9 110 U1 4 U2 37 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0169-8095 EI 1873-2895 J9 ATMOS RES JI Atmos. Res. PD MAY PY 2008 VL 88 IS 2 BP 174 EP 182 DI 10.1016/j.atmosres.2007.10.016 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 300CH UT WOS:000255801400008 ER PT J AU Bhowmick, R Clemens, BM Cruden, BA AF Bhowmick, Ranadeep Clemens, Bruce M. Cruden, Brett A. TI Parametric analysis of chirality families and diameter distributions in single-wall carbon nanotube production by the floating catalyst method SO CARBON LA English DT Article ID RAMAN-SPECTROSCOPY; PURITY EVALUATION; GROWTH; HYDROCARBONS; TEMPERATURE; STRANDS AB we report a detailed parametric analysis of the production of single-wall carbon nanotubes (SWCNTs) by the floating catalyst method in a vertical furnace using an alcohol precursor. From a combined study of Raman and absorption spectroscopies and transmission electron microscopy, we have developed a semi-quantitative way of estimating the diameter and chiral family distribution of the SWCNTs produced. This approach shows that increased residence times and higher concentrations of metal catalyst in the precursor solution (i.e. ferrocene in ethanol) increase the diameter of the tubes produced. Increasing growth temperatures result in the formation of both larger and small diameter SWCNTs, in contrast to previous reports of increasing diameter with temperature. Varying these parameters could be effective in tailoring the size distribution of the SWCNTs to meet the needs of specific applications. Also evidence is presented to show the absence of red shifting of the Raman radial breathing modes, expected due to bundling, of the metallic tubes. (C) 2008 Elsevier Ltd. All rights reserved. C1 [Cruden, Brett A.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. [Bhowmick, Ranadeep; Clemens, Bruce M.] Stanford Univ, Stanford, CA 94305 USA. RP Cruden, BA (reprint author), NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. EM Brett.A.Cruden@nasa.gov NR 36 TC 22 Z9 22 U1 0 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0008-6223 EI 1873-3891 J9 CARBON JI Carbon PD MAY PY 2008 VL 46 IS 6 BP 907 EP 922 DI 10.1016/j.carbon.2008.02.020 PG 16 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 304VU UT WOS:000256138000011 ER PT J AU Dufey, J Lemaitre, A Rambaux, N AF Dufey, Julien Lemaitre, Anne Rambaux, Nicolas TI Planetary perturbations on Mercury's libration in longitude SO CELESTIAL MECHANICS & DYNAMICAL ASTRONOMY LA English DT Article DE Mercury's libration; Mercury rotation; planetary perturbations ID HAMILTONIAN MODEL; ROTATION; MOTION; PERIOD AB Two space missions dedicated to Mercury (MESSENGER and BepiColombo) aim at understanding its rotation and confirming the existence of a liquid core. This double challenge requires much more accurate models for the spin-orbit resonant rotation of Mercury. The purpose of this paper is to introduce planetary perturbations on Mercury's rotation using an analytical method and to analyse the influence of the perturbations on the libration in longitude. Applying a perturbation theory based on the Lie triangle, we were able to re-introduce short periodic terms into the averaged Hamiltonian and to compute the evolution of the rotational variables. The perturbations on Mercury's forced libration in longitude mainly come from the orbital motion of Mercury (with an amplitude around 41 arcsec that depends on the momenta of inertia). It is completed by various effects from Jupiter (11.86 and 5.93 year-periods), Venus (with a 5.66 year-period), Saturn (14.73 year-period), and the Earth (6.58 year-period). The amplitudes of the oscillations due to Jupiter and Venus are approximately 33% and 10% of those from the orbital motion of Mercury and the amplitudes of the oscillations due to Saturn and the Earth are approximately 3% and 2%. We compare the analytical results with the solution obtained from the spin-orbit numerical model SONYR. C1 [Dufey, Julien; Lemaitre, Anne; Rambaux, Nicolas] Univ Namur, Dept Math, B-5000 Namur, Belgium. [Rambaux, Nicolas] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Dufey, J (reprint author), Univ Namur, Dept Math, Rempart de la Vierge 8, B-5000 Namur, Belgium. EM julien.dufey@fundp.ac.be NR 21 TC 13 Z9 13 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0923-2958 J9 CELEST MECH DYN ASTR JI Celest. Mech. Dyn. Astron. PD MAY PY 2008 VL 101 IS 1-2 BP 141 EP 157 DI 10.1007/s10569-008-9143-8 PG 17 WC Astronomy & Astrophysics; Mathematics, Interdisciplinary Applications SC Astronomy & Astrophysics; Mathematics GA 308YO UT WOS:000256427000008 ER PT J AU Little, SA Hastings, LJ AF Little, Sally Ann Hastings, Leon J. TI 2007 Space Cryogenics Workshop SO CRYOGENICS LA English DT Editorial Material C1 [Little, Sally Ann; Hastings, Leon J.] Marshall Space Flight Ctr, Alpha Technol Inc, Huntsville, AL USA. RP Little, SA (reprint author), Marshall Space Flight Ctr, Alpha Technol Inc, Huntsville, AL USA. EM leon.j.hastings@nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0011-2275 J9 CRYOGENICS JI Cryogenics PD MAY-JUN PY 2008 VL 48 IS 5-6 BP 173 EP 173 DI 10.1016/j.cryogenics.2008.03.005 PG 1 WC Thermodynamics; Physics, Applied SC Thermodynamics; Physics GA 322LV UT WOS:000257377500001 ER PT J AU Chato, DJ AF Chato, David J. TI Cryogenic fluid transfer for exploration SO CRYOGENICS LA English DT Article; Proceedings Paper CT 22nd Space Cryogenics Workshop CY JUL 12-13, 2007 CL Huntsville, AL SP NASA Marshall Space Flight Ctr DE hydrogen; oxygen; fluid acquisition; space cryogenics AB This paper discusses current plans and issues for exploration that involve the use of cryogenic transfer. The benefits of cryogenic transfer to exploration missions are examined. The current state of the art of transfer technology is reviewed. Mission concepts of operation for exploration are presented, and used to qualitatively discuss the performance benefits of transfer. The paper looks at the challenges faced to implement a cryogenic transfer system and suggest approaches to address them with advanced development research. Transfer rates required for exploration are shown to have already been achieved in ground test. Cost effective approaches to the required on-orbit demonstration are suggested. Published by Elsevier Ltd. C1 NASA Glenn, Res Ctr, Cleveland, OH 44135 USA. RP Chato, DJ (reprint author), NASA Glenn, Res Ctr, 21000 Brook Pk Rd,Mail Stop 86-2, Cleveland, OH 44135 USA. EM David.J.Chato@nasa.gov RI Chato, David/B-2698-2013 OI Chato, David/0000-0003-2990-0646 NR 31 TC 4 Z9 5 U1 0 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0011-2275 J9 CRYOGENICS JI Cryogenics PD MAY-JUN PY 2008 VL 48 IS 5-6 BP 206 EP 209 DI 10.1016/j.cryogenics.2008.03.013 PG 4 WC Thermodynamics; Physics, Applied SC Thermodynamics; Physics GA 322LV UT WOS:000257377500006 ER PT J AU Notardonato, WU AF Notardonato, W. U. TI Recovery of lunar surface access module residual and reserve propellants SO CRYOGENICS LA English DT Article; Proceedings Paper CT 22nd Space Cryogenics Workshop CY JUL 12-13, 2007 CL Huntsville, AL SP NASA Marshall Space Flight Ctr DE cryogenic; operations; residual propellants; lunar surface cryogenics AB The vision for space exploration calls for human exploration of the lunar surface in the 2020 timeframe. Sustained human exploration of the lunar surface will require supply, storage, and distribution of consumables for a variety of mission elements. These elements include propulsion systems for ascent and descent stages, life support for habitats and extra-vehicular activity, and reactants for power systems. NASA KSC has been tasked to develop technologies and strategies for consumables transfer for lunar exploration as part of the exploration technology development program. This paper will investigate details of operational concepts to scavenge residual propellants from the lunar descent propulsion system, Predictions on the mass of residuals and reserves are made. Estimates of heat transfer and boil-off rates are calculated and transient tank thermodynamic issues post-engine cutoff are modeled. Recovery and storage options, including cryogenic liquid, vapor and water are discussed, and possible reuse of LSAM assets is presented. Published by Elsevier Ltd. C1 NASA, Cryogen Test Lab, Kennedy Space Ctr, FL 32899 USA. RP Notardonato, WU (reprint author), NASA, Cryogen Test Lab, Kennedy Space Ctr, FL 32899 USA. EM bill.notardonato@nasa.gov NR 10 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0011-2275 J9 CRYOGENICS JI Cryogenics PD MAY-JUN PY 2008 VL 48 IS 5-6 BP 210 EP 216 DI 10.1016/j.cryogenics.2008.03.015 PG 7 WC Thermodynamics; Physics, Applied SC Thermodynamics; Physics GA 322LV UT WOS:000257377500007 ER PT J AU Flachbart, RH Hastings, LJ Hedayat, A Nelson, SL Tucker, SP AF Flachbart, R. H. Hastings, L. J. Hedayat, A. Nelson, S. L. Tucker, S. P. TI Thermodynamic vent system performance testing with subcooled liquid methane and gaseous helium pressurant SO CRYOGENICS LA English DT Article; Proceedings Paper CT 22nd Space Cryogenics Workshop CY JUL 12-13, 2007 CL Huntsville, AL SP NASA Marshall Space Flight Ctr DE cryogenic test; thermodynamic; vent; methane; helium AB LCH4 testing was conducted at the Marshall Space Flight Center using the multipurpose hydrogen test bed (MHTB) to evaluate the performance of a spray-bar thermodynamic vent system (TVS) with sub-cooled LCH4 and gaseous helium (GHe) pressurant. Thirteen days of testing were performed in November 2006, with total tank heat leak conditions of about 715 W and 420 W at a fill level of approximately 90%. A total of 23 TVS cycles were completed. The TVS successfully controlled the ullage pressure within a prescribed control band but did not maintain a stable liquid saturation pressure. This was likely due to a TVS design not optimized for this particular propellant and test conditions, and possibly due to a large artificially induced heat input directly into the liquid. (C) 2008 Elsevier Ltd. All rights reserved. C1 [Flachbart, R. H.; Hedayat, A.; Nelson, S. L.; Tucker, S. P.] NASA, Marshall Space Flight Ctr, Engn Directorate, Huntsville, AL 35812 USA. [Hastings, L. J.] Alpha Technol Inc, Huntsville, AL 35812 USA. RP Flachbart, RH (reprint author), NASA, Marshall Space Flight Ctr, Engn Directorate, Huntsville, AL 35812 USA. EM robin.h.flachbart@nasa.gov NR 5 TC 2 Z9 4 U1 0 U2 1 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0011-2275 J9 CRYOGENICS JI Cryogenics PD MAY-JUN PY 2008 VL 48 IS 5-6 BP 217 EP 222 DI 10.1016/j.cryogenics.2008.03.011 PG 6 WC Thermodynamics; Physics, Applied SC Thermodynamics; Physics GA 322LV UT WOS:000257377500008 ER PT J AU Fesmire, JE Sass, JP AF Fesmire, J. E. Sass, J. P. TI Aerogel insulation applications for liquid hydrogen launch vehicle tanks SO CRYOGENICS LA English DT Article; Proceedings Paper CT 22nd Space Cryogenics Workshop CY JUL 12-13, 2007 CL Huntsville, AL SP NASA Marshall Space Flight Ctr DE adsorbents; hydrogen; liquid helium; thermal conductivity; temperature sensors AB Solutions to thermal insulation problems using aerogel beads were demonstrated for space launch vehicles using a model of the space shuttle external tank's liquid hydrogen (LH2) intertank. Test results using liquid helium show that with aerogel, the nitrogen mass inside the intertank is greatly reduced and free liquid nitrogen is eliminated. Physisorption within the aerogel was also investigated, showing that the sorption ratio (liquid nitrogen to aerogel beads) is about 62%. The insulating effectiveness of the aerogel shows that cryopumping is driven by thermal communication between warm and cold surfaces. This technology can solve heat transfer problems and augment existing thermal protection systems on launch vehicles. Published by Elsevier Ltd. C1 [Fesmire, J. E.; Sass, J. P.] NASA, Cryogen Test Lab, Kennedy Space Ctr, FL 32899 USA. RP Fesmire, JE (reprint author), NASA, Cryogen Test Lab, Mail Code KT-E, Kennedy Space Ctr, FL 32899 USA. EM james.e.fesmire@nasa.gov NR 6 TC 19 Z9 24 U1 0 U2 18 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0011-2275 J9 CRYOGENICS JI Cryogenics PD MAY-JUN PY 2008 VL 48 IS 5-6 BP 223 EP 231 DI 10.1016/j.cryogenics.2008.03.014 PG 9 WC Thermodynamics; Physics, Applied SC Thermodynamics; Physics GA 322LV UT WOS:000257377500009 ER PT J AU Bolshinskiy, LG Hastings, LJ Statham, G AF Bolshinskiy, L. G. Hastings, L. J. Statham, G. TI Cryogenic capillary screen heat entrapment SO CRYOGENICS LA English DT Article; Proceedings Paper CT 22nd Space Cryogenics Workshop CY JUL 12-13, 2007 CL Huntsville, AL SP NASA Marshall Space Flight Ctr DE nitrogen; heat transfer; fluid acquisition; space cryogenics AB Cryogenic liquid acquisition devices (LADs) for space-based propulsion interface directly with the feed system, which can be a significant heat leak source. Further, the accumulation of thermal energy within LAD channels can lead to the loss of subcooled propellant conditions and result in feed system cavitation during propellant outflow. Therefore, the fundamental question addressed by this program was: "To what degree is natural convection in a cryogenic liquid constrained by the capillary screen meshes envisioned for LADs?" Testing was first conducted with water as the test fluid, followed by liquid nitrogen (LN2) tests. In either case, the basic experimental approach was to heat the bottom of a cylindrical column of test fluid to establish stratification patterns measured by temperature sensors located above and below a horizontal screen barrier position. Experimentation was performed without barriers, with screens, and with a solid barrier. The two screen meshes tested were those typically used by LAD designers, 200 x 1400 and 325 x 2300, both with Twill Dutch Weave. Upon consideration of both the water and LN2 data, it was concluded that heat transfer across the screen meshes was dependent upon barrier thermal conductivity and that the capillary screen meshes were impervious to natural convection currents. (C) 2008 Published by Elsevier Ltd. C1 [Hastings, L. J.] Alpha Technology Inc, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. [Bolshinskiy, L. G.] Univ Alabama, Huntsville Jacobs Engn MSFC Grp, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. [Statham, G.] ERC Inc, Jacobs Engn MSFC Grp, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Hastings, LJ (reprint author), Alpha Technology Inc, George C Marshall Space Flight Ctr, MSFC Mail Code ER23, Huntsville, AL 35812 USA. EM leon.j.hastings@nasa.gov NR 2 TC 2 Z9 2 U1 1 U2 1 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0011-2275 J9 CRYOGENICS JI Cryogenics PD MAY-JUN PY 2008 VL 48 IS 5-6 BP 232 EP 237 DI 10.1016/j.cryogenics.2008.03.019 PG 6 WC Thermodynamics; Physics, Applied SC Thermodynamics; Physics GA 322LV UT WOS:000257377500010 ER PT J AU Tuttle, J Pourrahimi, S Canavan, E DiPirro, M Shirron, P AF Tuttle, James Pourrahimi, Shahin Canavan, Edgar DiPirro, Michael Shirron, Peter TI Development of a lightweight low-current 10 K 4 T magnet for space-flight ADRs SO CRYOGENICS LA English DT Article; Proceedings Paper CT 22nd Space Cryogenics Workshop CY JUL 12-13, 2007 CL Huntsville, AL SP NASA Marshall Space Flight Ctr DE adiabatic demagnetization; superconducting magnets AB Future space missions will include detectors and other components cooled to cryogenic temperatures by adiabatic demagnetization refrigerators (ADRs) coupled with mechanical cryocoolers. in such systems the ADRs require lightweight, low-current superconducting magnets. At least one of an ADR's magnets must operate at the cryocooler's coldest stage temperature. This temperature should be as high as possible in order to improve operating efficiency and design flexibility. We previously reported the development of a lightweight (1 kg) low-current (8 A) Nb3Sn magnet which produces a 3 T central field at 10 K. We now report our progress in developing a new 10 K magnet of similar size made with smaller diameter Nb3Sn wire which will produce a 4 T central field with approximately 5 A. (C) 2008 Elsevier Ltd. All rights reserved. C1 [Tuttle, James; Canavan, Edgar; DiPirro, Michael; Shirron, Peter] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Pourrahimi, Shahin] Superconducting Syst Inc, Waltham, MA USA. RP Tuttle, J (reprint author), NASA, Goddard Space Flight Ctr, Code 552, Greenbelt, MD 20771 USA. EM jim.tuttle@nasa.gov NR 5 TC 1 Z9 1 U1 0 U2 4 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0011-2275 J9 CRYOGENICS JI Cryogenics PD MAY-JUN PY 2008 VL 48 IS 5-6 BP 248 EP 252 DI 10.1016/j.cryogenics.2008.03.002 PG 5 WC Thermodynamics; Physics, Applied SC Thermodynamics; Physics GA 322LV UT WOS:000257377500012 ER PT J AU Pourrahimi, S Williams, J Punchard, W Tuttle, J DiPirroc, M Canavan, E Shirron, P AF Pourrahimi, Shahin Williams, John Punchard, William Tuttle, James DiPirroc, Michael Canavan, Edgar Shirron, Peter TI Comparison of approaches to shielding of ADR magnets SO CRYOGENICS LA English DT Article; Proceedings Paper CT 22nd Space Cryogenics Workshop CY JUL 12-13, 2007 CL Huntsville, AL SP NASA Marshall Space Flight Ctr DE superconducting magnets; magnetic shielding; adiabatic demagnetization ID 10 K AB An important consideration in the use of magnets in adiabatic demagnetization refrigeration (ADR) applications is shielding of the other instruments in the vicinity of the superconducting magnets. Shielding without proper optimization can add unnecessary weight to the magnet system that can amount to a few times the weight of the superconducting magnet itself. This article reports on examination of various approaches to shielding of ADR magnets, and measurements conducted on both passive and active shielding of a sample Nb3Sn solenoidal magnet. Shielded ADR solenoidal magnets are also compared with self-shielding toroidal magnets in terms of overall weight, volume, and cooling capacity. (C) 2008 Published by Elsevier Ltd. C1 [Pourrahimi, Shahin; Williams, John] Superconducting Syst Inc, Waltham, MA 02453 USA. [Punchard, William] Stern Magnet LLC, Waltham, MA USA. [Tuttle, James; DiPirroc, Michael; Canavan, Edgar; Shirron, Peter] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Pourrahimi, S (reprint author), Superconducting Syst Inc, 90 Rumford Ave, Waltham, MA 02453 USA. EM pourrahimi@superconductingsytems.com NR 5 TC 3 Z9 3 U1 1 U2 4 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0011-2275 J9 CRYOGENICS JI Cryogenics PD MAY-JUN PY 2008 VL 48 IS 5-6 BP 253 EP 257 DI 10.1016/j.cryogenics.2008.03.017 PG 5 WC Thermodynamics; Physics, Applied SC Thermodynamics; Physics GA 322LV UT WOS:000257377500013 ER PT J AU Piryatinska, A Glazman, RE Weichman, PB AF Piryatinska, Alexandra Glazman, Roman E. Weichman, Peter B. TI Near-zonal wavefronts and related features of equatorial dynamics derived from satellite altimeter data SO DYNAMICS OF ATMOSPHERES AND OCEANS LA English DT Article DE Rossby waves; satellite altimetry; statistical inhomogeneity; equatorial ocean dynamics; wavefronts ID ROSSBY WAVES; PACIFIC-OCEAN; NORTH PACIFIC; TOPEX/POSEIDON; MODEL; PROPAGATION; VARIABILITY; DISPERSION; DRIVEN AB A new statistical approach to analyzing large-scale oceanic motions characterized by strong statistical inhomogeneity in the meridional direction is developed and applied to a 9-year series of satellite altimeter observations in the Tropical Pacific between 20 degrees S and 20 degrees N. A special treatment of meridional variations permits quantitative characterization of latitudinally alternating, zonally elongated features of the sea surface height field. Their frequency and length scales demonstrate that these features pertain to baroclinic large-scale wave motions, such as highly irregular Rossby waves. Since the sea surface height field at each latitude is generally found to be dominated by a few strong spectral peaks (semi-annual, annual, near-tetra-annual) for both westward and eastward propagating motions, a dominant wavevector may be associated with each such selected range of temporal and zonal scales. The meridional component of the wavevector is derived from the phase shift of the cross-spectrum between two neighboring latitudes 1 degrees apart. The latitude dependence of these wavevectors may be instructively represented as a set of wavefronts that provide a global picture of the dominant flows. (C) 2007 Elsevier B.V. All rights reserved. C1 [Weichman, Peter B.] BAE Syst, Adv Informat Technol, Burlington, MA 01803 USA. [Piryatinska, Alexandra] San Francisco State Univ, Dept Math, San Francisco, CA 94132 USA. [Glazman, Roman E.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Weichman, PB (reprint author), BAE Syst, Adv Informat Technol, 6 New England Execut Pl, Burlington, MA 01803 USA. EM peter.weichman@baesystems.com NR 26 TC 0 Z9 0 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0377-0265 J9 DYNAM ATMOS OCEANS JI Dyn. Atmos. Oceans PD MAY PY 2008 VL 45 IS 1-2 BP 26 EP 45 DI 10.1016/j.dynatmoce.2007.11.002 PG 20 WC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Oceanography SC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Oceanography GA 311DT UT WOS:000256581300002 ER PT J AU Brewer, R AF Brewer, Ron TI Radiated susceptibility SO EE-EVALUATION ENGINEERING LA English DT Article C1 NASA Kennedy Space Ctr, Kennedy Space Ctr, FL 32899 USA. RP Brewer, R (reprint author), NASA Kennedy Space Ctr, Kennedy Space Ctr, FL 32899 USA. EM ronbrewer@ieee.org NR 0 TC 0 Z9 0 U1 0 U2 0 PU NELSON PUBLISHING PI NOKOMIS PA 2500 NORTH TAMIAMI TRAIL, NOKOMIS, FL 34275-3482 USA SN 0149-0370 J9 EE-EVAL ENG JI EE-Eval. Eng. PD MAY PY 2008 VL 47 IS 5 BP 62 EP + PG 7 WC Engineering, Electrical & Electronic SC Engineering GA 294VM UT WOS:000255434400008 ER PT J AU Salinas, KA Hemmer, MJ Harris, PS Walker, CC AF Salinas, Kimberly A. Hemmer, Michael J. Harris, Peggy S. Walker, Calvin C. TI A simple and rapid matrix-assisted laser desorption/ionization time of flight mass spectrometry method to screen fish plasma samples for estrogen-responsive biomarkers SO ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY LA English DT Article DE endocrine-disrupting compounds; protein profiling; matrix-assisted laser desorption/ionization; sheepshead minnow; estrogen ID PROTEIN EXPRESSION SIGNATURES; FATHEAD MINNOW VITELLOGENIN; RAINBOW-TROUT; PROSTATE-CANCER; ZONA RADIATA; ENVIRONMENTAL ESTROGENS; CYPRINODON-VARIEGATUS; LIQUID-CHROMATOGRAPHY; EGGSHELL PROTEIN; OVARIAN-CANCER AB In the present study, we describe and evaluate the performance of a simple and rapid mass spectral method for screening fish plasma for estrogen-responsive biomarkers using matrix-assisted laser desorption/ionization (MALDI) time of flight mass spectrometry coupled with a short-term fish assay. Adult male sheepshead minnows (Cyprinodon variegatus) were placed into aquaria consisting of vehicle control and the following estrogen agonist treatments: 17 beta-estradiol (0.00625, 0.0125, 0.025, 0.05, 0.1, 0.2, 0.5, and 1.0 mu g/L, 4-tert-pentylphenol (100 mu g/L), methoxychlor (6 and 12 mu g/L), and bisphenol A (100 and 1,000 mu g/L). Treatments with chlorpyrifos (80 mu g/L) and endosulfan (0.6 mu g/L) served as nonestrogenic negative controls. Test concentrations were maintained using an intermittent flow-through dosing apparatus. Plasma was obtained from individuals, diluted and applied to an inert surface, and analyzed by MALDI. Multiple protein peaks, ranging from 2.9 to 12.9 kDa, were identified as markers of estrogenic effects when comparing estrogen-treated and control fish using interpercentile reference values. A binary classification tree model was constructed from plasma protein profiles of the vehicle control and the 0.2 mu g/L of 17 beta-estradiol treatments and then used to evaluate all samples. Treatments with the estrogen agonists 17 beta-estradiol, 4-tert-pentyl phenol, methoxychlor, and bisphenol-A generated reproducible diagnostic biomarkers based on the presence of specific estrogen-responsive plasma proteins. The controls and nonestrogenic compounds chlorpyrifos and endosulfan did not produce this estrogen-responsive protein profile. A no-observed-effect level for 17 beta-estradiol at 0.025 mu g/L was estimated from concentration-response exposures. The MALDI method described here provides a straightforward, sensitive, and specific tool to screen chemicals for estrogenic activity. C1 [Salinas, Kimberly A.; Hemmer, Michael J.; Harris, Peggy S.] US EPA, Natl Hlth & Environm Effects Res Lab, Gulf Ecol Div, Gulf Breeze, FL USA. [Walker, Calvin C.] Natl Ocean & Atmospher Adm, Natl Marine Fisheries Serv, Pascagoula, MS USA. RP Salinas, KA (reprint author), US EPA, Natl Hlth & Environm Effects Res Lab, Gulf Ecol Div, Gulf Breeze, FL USA. EM salinas.kimberly@epa.gov NR 31 TC 4 Z9 4 U1 0 U2 6 PU SOC ENVIRONMENTAL TOXICOLOGY & CHEMISTRY-SETAC PI PENSACOLA PA 1010 N 12TH AVE, PENSACOLA, FL 32501-3367 USA SN 0730-7268 J9 ENVIRON TOXICOL CHEM JI Environ. Toxicol. Chem. PD MAY PY 2008 VL 27 IS 5 BP 1175 EP 1183 DI 10.1897/07-226.1 PG 9 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA 289OL UT WOS:000255063700022 PM 18419181 ER PT J AU Maestrini, A Ward, J Chattopadhyay, G Schlecht, E Mehdi, I AF Maestrini, Alain Ward, John Chattopadhyay, Goutam Schlecht, Erich Mehdi, Imran TI Terahertz sources based on frequency multiplication and their applications SO FREQUENZ LA English DT Article DE THz technology; frequency multipliers; sources; Schottky diode; waveguide; GaAs membrane ID QUANTUM-CASCADE LASERS; POWER-AMPLIFIERS; GHZ; THZ; TECHNOLOGY; TRIPLER; PERFORMANCE; DOUBLER; CHAIN AB Compact. robust and broadband sources in the terahertz range are extremely important in diverse applications such as spectroscopy. imaging, communication, and radar. A review of the current state-of-the-art is presented with emphasis on Schottky diode based frequency multiplier technology. Frequency multiplier circuit chips fabricated on few micrometer thick GaAs membranes and packaged in low-loss waveguide circuits have demonstrated tens of microwatts Of Output power up to 1.9 THz. This breakthrough has enabled sensitive heterodyne receivers in the terahertz range that will be flown on an upcoming ESA mission to answer fundamental questions about our universe. C1 [Maestrini, Alain] Observ Paris, LERMA, F-75014 Paris, France. [Ward, John; Chattopadhyay, Goutam; Schlecht, Erich; Mehdi, Imran] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Maestrini, A (reprint author), Observ Paris, LERMA, 61 Ave Observ, F-75014 Paris, France. EM alain.maestrini@obspm.fr; john.ward@jpl.nasa.gov; goutam.chattopadhyay@jpl.nasa.gov; erich.schlecht@jpl.nasa.gov; Imran.mehdi@jpl.nasa.gov FU Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA; Observatoire de Paris, Laboratoire d'Etude du Rayonnement et de la Matiere en Astrophysique, France FX This work was supported by the Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA and the Observatoire de Paris, Laboratoire d'Etude du Rayonnement et de la Matiere en Astrophysique, France.; We are greatly indebted to the JPL machine shop for the exceptionally high precision of the waveguide blocks as well as to our colleagues who fabricated the integrated circuits, assembled the frequency multipliers, and tested them in the laboratory. NR 33 TC 22 Z9 22 U1 2 U2 11 PU FACHVERLAG SCHIELE SCHON PI BERLIN PA MARKGRAFENSTRASSE 11, D-10969 BERLIN, GERMANY SN 0016-1136 J9 FREQUENZ JI Frequenz PD MAY-JUN PY 2008 VL 62 IS 5-6 BP 118 EP 122 DI 10.1515/FREQ.2008.62.5-6.118 PG 5 WC Engineering, Electrical & Electronic SC Engineering GA 346WJ UT WOS:000259100000004 ER PT J AU Maleki, L AF Maleki, L. TI Space tests of relativistic gravity with precision clocks and atom interferometers SO GENERAL RELATIVITY AND GRAVITATION LA English DT Article DE space tests of gravity; experimental relativity; atomic clocks; atom interferometers; variation of constants; spin gravity; fundamental tests AB Precision clocks and interferometers in space can test relativistic gravity with extremely high sensitivity. Yet, only a single such test has been performed, namely the celebrated flight of a hydrogen maser in a sub-orbital trajectory in 1976 (GP-A mission). This paper suggests some of the obstacles to space flight of precision instruments, and describes how the emergence of new technology might offer a pathway for removing those obstacles. A brief review of emerging technologies is made, and new mission concepts based on them are described. Some of the technologies that can impact more tests of relativistic gravity in space at a more distant future are also described. C1 [Maleki, L.] OEwaves Inc, Pasadena, CA 91106 USA. [Maleki, L.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Maleki, L (reprint author), OEwaves Inc, 1010 E Union St, Pasadena, CA 91106 USA. EM Lute@OEwaves.com NR 21 TC 0 Z9 0 U1 1 U2 7 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0001-7701 J9 GEN RELAT GRAVIT JI Gen. Relativ. Gravit. PD MAY PY 2008 VL 40 IS 5 BP 895 EP 905 DI 10.1007/s10714-007-0581-5 PG 11 WC Astronomy & Astrophysics; Physics, Multidisciplinary; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 289ZC UT WOS:000255091400002 ER PT J AU Benedix, GK Ketcham, RA Wilson, L Mccoy, TJ Bogard, DD Garrison, DH Herzog, GF Xue, S Klein, J Middleton, R AF Benedix, G. K. Ketcham, R. A. Wilson, L. McCoy, T. J. Bogard, D. D. Garrison, D. H. Herzog, G. F. Xue, S. Klein, J. Middleton, R. TI The formation and chronology of the PAT 91501 impact-melt L chondrite with vesicle-metal-sulfide assemblages SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID ACCELERATOR-MASS-SPECTROMETRY; PARENT BODY; COSMOGENIC NUCLIDES; EXPOSURE AGES; METEORITIC SAMPLE; PRODUCTION-RATES; PORTALES VALLEY; IRON-METEORITES; THERMAL HISTORY; H-CHONDRITES AB The L chondrite Patuxent Range (PAT) 91501 is an 8.5-kg unshocked, homogeneous, igneous-textured impact melt that cooled slowly compared to other meteoritic impact melts in a crater floor melt sheet or sub-crater dike [Mittlefehldt D. W. and Lindstrom M. M. (200 1) Petrology and geochemistry of Patuxent Range 91501 and Lewis Cliff 88663. Meteoritics Planet. Sci. 36, 439 - 457]. We conducted mineralogical and tomographic studies of previously unstudied mm- to cm-sized rnetal-sulfide-vesicle assemblages and chronologic studies of the silicate host. Metal-sulfide clasts constitute about 1 vol.%, comprise zoned taenite, troilite, and pentlandite, and exhibit a consistent orientation between metal and Sulfide and of metal-sulfide contacts. Vesicles make up similar to 2 vol.% and exhibit a similar orientation of long axes. Ar-39 - Ar-40 measurements probably date the time of impact at 4.461 +/- 0.008 Gyr B.P. Cosmogenic noble gases and Be-10 and Al-26 activities suggest a pre-atmospheric radius of 40 - 60 cm and a cosmic ray exposure age of 25 - 29 Myr, similar to ages of a cluster of L chondrites. PAT 91501 dates the oldest known impact on the L chondrite parent body. The dominant vesicle-forming gas was S-2 (similar to 15 - 20 ppm), which formed in equilibrium with impact-inelted sulfides. The meteorite formed in an impact melt dike beneath a crater, as did other impact melted L chondrites, such as Chico. Cooling and solidification occurred over similar to 2 h. During this time, similar to 90% of metal and sulfide segregated from the local melt. Remaining metal and sulfide grains oriented themselves in the local gravitational field, a feature nearly unique among meteorites. Many of these metal-sulfide grains adhered to vesicles to form aggregates that may have been close to neutrally buoyant. These aggregates would have been carried upward with the residual melt, inhibiting further buoyancy-driven segregation. Although similar processes operated individually in other chondritic impact melts, their interaction produced the unique assemblage observed in PAT 91501. (c) 2008 Elsevier Ltd. All rights reserved. C1 [Benedix, G. K.] Nat Hist Museum, Dept Mineral, IARC, London SW7 5BD, England. [Ketcham, R. A.] Univ Texas Austin, Jackson Sch Geosci, Dept Geol Sci, Austin, TX 78712 USA. [Wilson, L.] Univ Lancaster, Dept Environm Sci, Lancaster LA1 4YQ, England. [McCoy, T. J.] Smithsonian Inst, Natl Museum Nat Hist, Dept Mineral Sci, Washington, DC 20560 USA. [Bogard, D. D.] NASA, Lyndon B Johnson Space Ctr, ARES, Houston, TX 77058 USA. [Garrison, D. H.] ESCG Barrios Technol, Houston, TX 77058 USA. [Herzog, G. F.; Xue, S.] Rutgers State Univ, Piscataway, NJ 08854 USA. [Klein, J.; Middleton, R.] Univ Penn, Philadelphia, PA 19104 USA. RP Benedix, GK (reprint author), Nat Hist Museum, Dept Mineral, IARC, Cromwell Rd, London SW7 5BD, England. EM g.benedix@nhm.ac.uk RI Ketcham, Richard/B-5431-2011; Klein, Jeffrey/E-3295-2013; OI Ketcham, Richard/0000-0002-2748-0409; Benedix, Gretchen/0000-0003-0990-8878 NR 58 TC 20 Z9 20 U1 0 U2 7 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0016-7037 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD MAY 1 PY 2008 VL 72 IS 9 BP 2417 EP 2428 DI 10.1016/j.gca.2008.02.010 PG 12 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 297GL UT WOS:000255605000012 ER PT J AU Beer, R Shephard, MW Kulawik, SS Clough, SA Eldering, A Bowman, KW Sander, SP Fisher, BM Payne, VH Luo, MZ Osterman, GB Worden, JR AF Beer, Reinhard Shephard, Mark W. Kulawik, Susan S. Clough, Shepard A. Eldering, Annmarie Bowman, Kevin W. Sander, Stanley P. Fisher, Brendan M. Payne, Vivienne H. Luo, Mingzhao Osterman, Gregory B. Worden, John R. TI First satellite observations of lower tropospheric ammonia and methanol SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID EMISSION SPECTROMETER; ATMOSPHERIC AMMONIA; SPACE; INSTRUMENT; RETRIEVAL; MODEL; AREA AB [1] The Tropospheric Emission Spectrometer (TES) on the EOS Aura satellite makes global measurements of infrared radiances which are used to derive profiles of species such as O(3), CO, H(2)O, HDO and CH(4) as routine standard products. In addition, TES has a variety of special modes that provide denser spatial mapping over a limited geographical area. A continuous-coverage mode ( called "transect'', about 460 km long) has now been used to detect additional molecules indicative of regional air pollution. On 10 July 2007 at about 05: 37 UTC (13: 24 LMST) TES conducted such a transect observation over the Beijing area in northeast China. Examination of the residual spectral radiances following the retrieval of the TES standard products revealed surprisingly strong features attributable to enhanced concentrations of ammonia (NH(3)) and methanol (CH(3)OH), well above the normal background levels. This is the first time that these molecules have been detected in space-based nadir viewing measurements that penetrate into the lower atmosphere. C1 [Beer, Reinhard; Kulawik, Susan S.; Eldering, Annmarie; Bowman, Kevin W.; Sander, Stanley P.; Fisher, Brendan M.; Luo, Mingzhao; Osterman, Gregory B.; Worden, John R.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Clough, Shepard A.] Clough Radiat Associates LLC, Lexington, MA 02420 USA. [Shephard, Mark W.; Payne, Vivienne H.] Atmospher & Environm Res Inc, Lexington, MA 02421 USA. RP Beer, R (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM reinhard.beer@jpl.nasa.gov RI Payne, Vivienne/D-9713-2012 NR 23 TC 45 Z9 46 U1 3 U2 12 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAY 1 PY 2008 VL 35 IS 9 AR L09801 DI 10.1029/2008GL033642 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 297BX UT WOS:000255593200002 ER PT J AU Lissauer, JJ Chambers, JE AF Lissauer, Jack J. Chambers, John E. TI Solar and planetary destabilization of the Earth-Moon triangular Lagrangian points SO ICARUS LA English DT Article DE trojan asteroids; near-Earth objects; Moon; Earth; satellites, dynamics ID SYMPLECTIC INTEGRATOR; SYSTEMS; NEPTUNE; TROJANS AB In the restricted circular three-body problem, two massive bodies travel on circular orbits about their mutual center of mass and gravitationally perturb the motion of a massless particle. The triangular Lagrange points, L-4 and L-5, form equilateral triangles with the two massive bodies and lie in their orbital plane. Provided the primary is at least 27 times as massive as the secondary, orbits near L-4 and L-5 can remain close to these locations indefinitely. More than 2200 cataloged asteroids librate about the L-4 and L-5 points of the Sun-Jupiter system, and five bodies have been discovered around the L-4 point of the Sun-Neptune system. Small satellites have also been found librating about the L4 and L-5 points of two of Saturn's moons. However, no objects have been discovered around the Earth-Moon L-4 and L-5 points. Using numerical integrations, we show that orbits near the Earth-Moon L-4 and L-5 points can survive for over a billion years even when solar perturbations are included, but the further addition of the far smaller perturbations from other planets destabilize these orbits within several million years. Thus, the lack of observed objects in these regions cannot be used as a constraint on Solar System formation, nor on the tidal evolution of the Moon's orbit. (C) 2008 Elsevier Inc. All rights reserved. C1 [Lissauer, Jack J.] NASA, Ames Res Ctr, Space Sci Astrobiol Div, Moffett Field, CA 94035 USA. [Chambers, John E.] Carnegie Inst Washington, Dept Terr Magnetism, Washington, DC 20015 USA. RP Lissauer, JJ (reprint author), NASA, Ames Res Ctr, Space Sci Astrobiol Div, Moffett Field, CA 94035 USA. EM jackj.lissauer@nasa.gov NR 13 TC 3 Z9 3 U1 0 U2 2 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD MAY PY 2008 VL 195 IS 1 BP 16 EP 27 DI 10.1016/j.icarus.2007.12.024 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 295HR UT WOS:000255466100002 ER PT J AU Villanueva, GL Mumma, MJ Novak, RE Hewagama, T AF Villanueva, Geronimo L. Mumma, Michael. J. Novak, Robert E. Hewagama, Tilak TI Identification of a new band system of isotopic CO2 near 3.3 mu m: Implications for remote sensing of biomarker gases on Mars SO ICARUS LA English DT Article DE infrared observations; spectroscopy; Mars, atmosphere; astrobiology ID THERMAL EMISSION SPECTROMETER; CARBON-DIOXIDE; ECHELLE SPECTROGRAPH; ENERGY-LEVELS; ATMOSPHERE; TEMPERATURE; INTENSITIES; METHANE; REGION; WATER AB We present the discovery of a new vibrational band system of isotopic CO2 (carbon dioxide) near 3.3 mu m, with multiple strong P, Q and R lines in the prime spectral region used to search for Mars CH4 (methane). The band system was discovered on Mars using high-resolution spectrometers (lambda/delta lambda > 40,000, CSHELL and NIRSPEC) at telescopes (NASA-IRTF and Keck-2) atop Mauna Kea, HI. The observed line intensities and frequencies agree very well with values predicted by a vibrational band model that. we developed using known parameters for the molecular levels involved. Using this model, we synthesized spectra for different observing conditions (from Space and ground-based telescopes) and for different spectral resolving powers (5000 to 40,000). Although the total atmospheric burden on Mars is more than 150 times smaller than on Earth, the greater mixing ratio of CO2 ensures that its column abundance on Mars is almost 20 times greater than on Earth. Thus, weak telluric CO2 band systems appear much stronger on Mars. Many molecules of possible biological and geothermal interest have strong signatures at these wavelengths, in particular hydrocarbons owing to their strong ro-vibrational C-H stretching modes. For example, the new isotopic CO2 band-system encompasses lines of CH4, C2H6 (ethane), CH3OH (methanol) and H2O (water). Implications for previous and future searches of biomarker gases are presented. (C) 2007 Elsevier Inc. All rights reserved. C1 [Villanueva, Geronimo L.; Mumma, Michael. J.; Hewagama, Tilak] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Novak, Robert E.] Iona Coll, Dept Phys, New Rochelle, NY 10801 USA. [Hewagama, Tilak] Univ Maryland, Dept Astron, College Pk, MD 20742 USA. RP Villanueva, GL (reprint author), NASA, Goddard Space Flight Ctr, Mailstop 693, Greenbelt, MD 20771 USA. EM geronimo.villanueva@nasa.gov RI Hewagama, T/C-8488-2012; mumma, michael/I-2764-2013 NR 26 TC 36 Z9 36 U1 0 U2 10 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD MAY PY 2008 VL 195 IS 1 BP 34 EP 44 DI 10.1016/j.icarus.2007.11.014 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 295HR UT WOS:000255466100004 ER PT J AU Poulet, F Arvidson, RE Gomez, C Morris, RV Bibring, JP Langevin, Y Gondet, B Griffes, J AF Poulet, F. Arvidson, R. E. Gomez, C. Morris, R. V. Bibring, J. -P. Langevin, Y. Gondet, B. Griffes, J. TI Mineralogy of Terra Meridiani and western Arabia Terra from OMEGA/MEx and implications for their formation SO ICARUS LA English DT Article DE Mars, surface; mineralogy; spectroscopy ID REFLECTANCE SPECTROSCOPY; EARLY MARS; SEDIMENTARY-ROCKS; CRATERED TERRAIN; HEMATITE; PLANUM; SURFACE; ENVIRONMENT; IRON; EXPRESS AB Analyses of Mars Express OMEGA hyperspectral data (0.4-2.7 mu m) for Terra Meridiani and western Arabia Terra show that the northern mantled cratered terrains are covered by dust that is spectrally dominated by nanophase ferric oxides. Dark aeolian dunes inside craters and dark streaks extending from the dunes into the intercrater areas in mantled cratered terrains in western Arabia Terra have similar pyroxene-rich signatures demonstrating that the dunes supply dark basaltic material to create dark streaks. The dissected cratered terrains to the south of the mantled terrains are dominated spectrally by both low-calcium and high-calcium pyroxenes with abundances of 20-30% each retrieved from nonlinear radiative transfer modeling. Spectra over the hematite-bearing plains in Meridiani Planum are characterized by very weak but unique spectral features attributed to a mixture of a dark and featureless component (possibly gray hematite) and minor olivine in some locations. Hydrated minerals (likely hydrous ferric sulfates and/or hydrous hydroxides) associated with poorly ferric crystalline phases are found in the etched terrains to the north and east of the hematite-bearing plains where erosion has exposed similar to 1 km of section of layered outcrops with high thermal inertias. These materials are also found in numerous craters in the northern Terra Meridiani and may represent outliers of the etched terrain materials. A few localized spots within the etched terrain also exhibit the spectral signature of Fe-rich phyllosilicates. The ensemble of observations show that the evidence for aqueous processes detected by the Opportunity Rover in Meridiani Planum is widespread and confirms the extended presence of surface or near-surface water over this large region of Mars. The scenarios of formation of Terra Meridiani ("dirty" acidic evaporite, impact surge or weathering of volcanic ash) cannot satisfactorily explain the mineralogy derived from the OMEGA observations. The formation of the etched terrains is consistent with leaching of iron sulfides and formation of sulfates and hydrated iron oxides, either in-place or via transport and evaporation of aqueous fluids and under aqueous conditions less acidic than inferred from rocks examined by Opportunity. (C) 2007 Elsevier Inc. All rights reserved. C1 [Poulet, F.; Gomez, C.; Bibring, J. -P.; Langevin, Y.; Gondet, B.] Univ Paris 11, Inst Astrophys Spatiale, F-91405 Orsay, France. [Arvidson, R. E.; Griffes, J.] Washington Univ, Dept Earth & Planetary Sci, St Louis, MO 63130 USA. [Morris, R. V.] NASA, Johnson Space Ctr, Houston, TX 77058 USA. [Griffes, J.] Smithsonian Inst, Natl Air & Space Museum, Ctr Earth Planetary Studies, Washington, DC 20013 USA. RP Poulet, F (reprint author), Univ Paris 11, Inst Astrophys Spatiale, F-91405 Orsay, France. EM francois.poulet@ias.u-psud.fr RI Gomez, Cecile/B-8473-2012 OI Gomez, Cecile/0000-0002-2986-430X NR 80 TC 57 Z9 57 U1 0 U2 4 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 EI 1090-2643 J9 ICARUS JI Icarus PD MAY PY 2008 VL 195 IS 1 BP 106 EP 130 DI 10.1016/j.icarus.2007.11.031 PG 25 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 295HR UT WOS:000255466100008 ER PT J AU Gilmore, MS Bornstein, B Merrill, MD Castano, R Greenwood, JP AF Gilmore, Martha S. Bornstein, Benjamin Merrill, Matthew D. Castano, Rebecca Greenwood, James P. TI Generation and performance of automated jarosite mineral detectors for visible/near-infrared spectrometers at Mars SO ICARUS LA English DT Article DE Mars, surface; spectroscopy; instrumentation; mineralogy ID MERIDIANI-PLANUM; REFLECTANCE SPECTROSCOPY; SPECTRA; PATHFINDER; SURFACE; DUST; CARBONATES; SMECTITES; HEMATITE; ALUNITE AB We have developed two automated detectors that can recognize the sulfate mineral jarosite in unknown visible to near-infrared spectra (3502500 nm). The two detectors are optimized for use within the terrestrial and martian atmospheres. The detectors are built from Support Vector Machines trained using a generative model to create linear mixtures of library mineral spectra. Both detectors performed with an average similar to 90% accuracy on laboratory spectra of single minerals and the laboratory and field spectra of rocks collected in a hydrothermal environment. This type of algorithm will contribute to the efficiency of onboard data analysis of landed and orbital visible/near-infrared spectrometers at Mars. (C) 2007 Elsevier Inc. All rights reserved. C1 [Gilmore, Martha S.; Merrill, Matthew D.; Greenwood, James P.] Wesleyan Univ, Dept Earth & Environm Sci, Middletown, CT 06459 USA. [Bornstein, Benjamin; Castano, Rebecca] Jet Propuls Lab, Pasadena, CA 91109 USA. RP Gilmore, MS (reprint author), Wesleyan Univ, Dept Earth & Environm Sci, 265 Church St, Middletown, CT 06459 USA. EM mgilmore@wesleyan.edu RI Gilmore, Martha/G-5856-2011 NR 59 TC 5 Z9 5 U1 1 U2 6 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD MAY PY 2008 VL 195 IS 1 BP 169 EP 183 DI 10.1016/j.icarus.2007.11.025 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 295HR UT WOS:000255466100011 ER PT J AU Shepard, MK Clark, BE Nolan, MC Howell, ES Magri, C Giorgini, JD Benner, LAM Ostro, SJ Harris, AW Warner, B Pray, D Pravec, P Fauerbach, M Bennett, T Klotz, A Behrend, R Correia, H Coloma, J Casulli, S Rivkin, A AF Shepard, Michael K. Clark, Beth Ellen Nolan, Michael C. Howell, Ellen S. Magri, Christopher Giorgini, Jon D. Benner, Lance A. M. Ostro, Steven J. Harris, Alan W. Warner, Brian Pray, Donald Pravec, Petr Fauerbach, Michael Bennett, Thomas Klotz, Alain Behrend, Raoul Correia, Horacio Coloma, Josep Casulli, Silvano Rivkin, Andrew TI A radar survey of M- and X-class asteroids SO ICARUS LA English DT Article DE asteroids; asteroids; composition; surfaces, asteroids ID MAIN-BELT ASTEROIDS; LIGHTCURVE OBSERVATIONS; ROTATIONAL PROPERTIES; PHOTOMETRIC DATA; OBJECTS; DENSITY; CHONDRITES; TAXONOMY; ARECIBO; ORIGIN AB We observed ten M- and X-class main-belt asteroids with the Arecibo Observatory's S-band (12.6 cm) radar. The X-class asteroids were targeted based on their albedos or other properties which suggested they might be M-class. This work brings the total number of main-belt M-class asteroids observed with radar to 14. We find that three of these asteroids have rotation rates significantly different from what was previously reported. Based on their high radar albedo, we find that only four of the fourteen-16 Psyche, 216 Kleopatra, 758 Mancunia, and 785 Zwetana-are almost certainly metallic. 129 Antigone has a moderately high radar albedo and we suggest it may be a CH/CB/Bencubbinite parent body. Three other asteroids, 97 Klotho, 224 Oceana, and 796 Sarita have radar albedos significantly higher than the average main belt asteroid and we cannot rule out a significant metal content for them. Five of our target asteroids, 16 Psyche, 129 Antigone, 135 Hertha, 758 Mancunia, and 785 Zwetana, show variations in their radar albedo with rotation. We can rule out shape and composition in most cases, leaving variations in thickness, porosity, or surface toughness of the regolith to be the most likely causes. With the exception of 129 Antigone, we find no hydrated M-class asteroids (W-class; Rivkin, A.S., Howell, E.S., Lebofsky, L.A., Clark, B.E., Britt, D.T., 2000. Icarus 145, 351-368) to have high radar albedos. (C) 2008 Elsevier Inc. All rights reserved. C1 [Shepard, Michael K.] Bloomsburg Univ Penn, Dep Geog & Geosci, Bloomsburg, PA 17815 USA. [Clark, Beth Ellen] Ithaca Coll, Ithaca, NY 14853 USA. [Nolan, Michael C.; Howell, Ellen S.] NAIC, Arecibo Observ, Arecibo, PR 00612 USA. [Magri, Christopher] Univ Maine, Farmington, ME 04938 USA. [Giorgini, Jon D.] Jet Propuls Lab, Pasadena, CA 91109 USA. [Harris, Alan W.] Space Sci Inst, La Canada Flintridge, CA 91011 USA. [Warner, Brian] Space Sci Inst, Palmer Divide Observ, Colorado Springs, CO USA. [Pray, Donald] Carbuncle Hill Observ, Greene, RI USA. [Pravec, Petr] Acad Sci Czech Republic, Astron Inst, CZ-25165 Ondrejov, Czech Republic. [Fauerbach, Michael] Florida Gulf Coast Univ, Ft Myers, FL 33965 USA. [Klotz, Alain] Observ Haute Provence, TAROT, St Micheal Lobservatorie, St Michel, France. [Behrend, Raoul] Ctr Astron, TAROT, St Micheal Lobservatorie, St Michel, France. [Coloma, Josep] Agrupac Astron Sabadell, Barcelona, Spain. [Casulli, Silvano] Observ Astron Vallemare Borbona, Rome, Italy. [Rivkin, Andrew] Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. RP Shepard, MK (reprint author), Bloomsburg Univ Penn, Dep Geog & Geosci, 400 E 2nd St, Bloomsburg, PA 17815 USA. EM mshepard@bloomu.edu RI Nolan, Michael/H-4980-2012; Pravec, Petr/G-9037-2014; Rivkin, Andrew/B-7744-2016 OI Nolan, Michael/0000-0001-8316-0680; Rivkin, Andrew/0000-0002-9939-9976 NR 68 TC 41 Z9 42 U1 1 U2 6 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 EI 1090-2643 J9 ICARUS JI Icarus PD MAY PY 2008 VL 195 IS 1 BP 184 EP 205 DI 10.1016/j.icarus.2007.11.032 PG 22 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 295HR UT WOS:000255466100012 ER PT J AU Shepard, MK Kressler, KM Clark, BE Ockert-Bell, ME Nolan, MC Howell, ES Magri, C Giorgini, JD Benner, LAM Ostro, SJ AF Shepard, Michael K. Kressler, Karelyn M. Clark, Beth Ellen Ockert-Bell, Maureen E. Nolan, Michael C. Howell, Ellen S. Magri, Christopher Giorgini, Jon D. Benner, Lance A. M. Ostro, Steven J. TI Radar observations of E-class asteroids 44 Nysa and 434 Hungaria SO ICARUS LA English DT Article DE asteroids; asteroids, composition; asteroids, surfaces; radar observations ID REGOLITH PROPERTIES; ARECIBO AB We observed the E-class main-belt Asteroids (MBAs) 44 Nysa and 434 Hungaria with Arecibo Observatory's S-band (12.6 cm) radar. Both asteroids exhibit polarization ratios higher than those measured for any other MBA: Nysa, mu(c) = 0.50 +/- 0.02 and Hungaria, mu(c) = 0.8 +/- 0.1. This is consistent with the high polarization ratios measured for every E-class near-Earth asteroid (NEA) observed by Benner et al. [Benner, L.A.M., and 10 collegues, 2008. Icarus, submitted for publication] and suggests a common cause. Our estimates of radar albedo are 0.19 +/- 0.06 for Nysa and 0.22 +/- 0.06 for Hungaria. These values are higher than those of most MBAs and, when combined with their high polarization ratios, suggest that the surface bulk density of both asteroids is high. We model Nysa as an ellipsoid of dimension 113 x 67 x 65 km (+/- 15%) giving an effective diameter D-eff = 79 +/- 10 km, consistent with previous estimates. The echo waveforms are not consistent with a contact binary as suggested by Kaasalainen et al. [Kaasalainen, M., Torppa, J., Piironen, J., 2002. Astron. Astrophys. 383, L19-L22]. We place a constraint on Hungaria's maximum diameter, D-max >= 11 km consistent with previous size estimates. (C) 2008 Elsevier Inc. All rights reserved. C1 [Shepard, Michael K.] Bloomsburg Univ Penn, Dept Geog & Geosci, Bloomsburg, PA 17815 USA. [Kressler, Karelyn M.] Earlham Coll, Dept Phys & Astron, Richmond, IN 47374 USA. [Clark, Beth Ellen; Ockert-Bell, Maureen E.] Ithaca Coll, Dept Phys, Ctr Nat Sci, Ithaca, NY 14850 USA. [Nolan, Michael C.; Howell, Ellen S.] Natl Astron & Ionosphere Ctr, Arecibo Observ, Arecibo, PR 00612 USA. [Magri, Christopher] Univ Marine Farmington, Farmington, ME 04938 USA. [Giorgini, Jon D.; Benner, Lance A. M.; Ostro, Steven J.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Shepard, MK (reprint author), Bloomsburg Univ Penn, Dept Geog & Geosci, 400 E 2nd St, Bloomsburg, PA 17815 USA. EM mshepard@bloomu.edu RI Nolan, Michael/H-4980-2012 OI Nolan, Michael/0000-0001-8316-0680 NR 24 TC 9 Z9 9 U1 0 U2 0 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD MAY PY 2008 VL 195 IS 1 BP 220 EP 225 DI 10.1016/j.icarus.2007.12.018 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 295HR UT WOS:000255466100014 ER PT J AU Beer, E Prialnik, D Podolak, A AF Beer, E. Prialnik, D. Podolak, A. TI The contribution of grains to the activity of comets - II. The brightness of the coma SO ICARUS LA English DT Article DE comets coma; comets dust; comets composition ID ICY GRAINS; MODEL; DUST; ATMOSPHERES; EVOLUTION; NUCLEUS; GAS AB We use the model of grain behavior in the coma developed by Beer et al. [Beer, E.H., Podolak, M., Prialnik, P., 2006. Icarus 180, 473-486] to compute the contribution of ice grains to the brightness of the coma. The motion of an ice grain along the comet-Sun axis is computed, taking into account gas drag, the gravity of the nucleus, and radiation pressure of sunlight. The sublimation of the grains is also included. We assume that the maximum distance that a grain travels along this axis is indicative of the size of the coma, and we compute the resultant brightness as a function of heliocentric distance. The results are then compared to observations. (C) 2007 Elsevier Inc. All rights reserved. C1 [Prialnik, D.; Podolak, A.] Tel Aviv Univ, Raymond & Beverly Sackler Fac Exact Sci, Dept Geophys & Planetary Sci, IL-69978 Tel Aviv, Israel. [Beer, E.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Podolak, A (reprint author), Tel Aviv Univ, Raymond & Beverly Sackler Fac Exact Sci, Dept Geophys & Planetary Sci, IL-69978 Tel Aviv, Israel. EM morris@post.tau.ac.il NR 31 TC 2 Z9 2 U1 0 U2 2 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD MAY PY 2008 VL 195 IS 1 BP 340 EP 347 DI 10.1016/j.icarus.2007.12.004 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 295HR UT WOS:000255466100019 ER PT J AU Barnes, JW Brown, RH Soderblom, L Sotin, C Le Mouelic, S Rodriguez, S Jaumann, R Beyer, RA Buratti, BJ Pitman, K Baines, KH Clark, R Nicholson, P AF Barnes, Jason W. Brown, Robert H. Soderblom, Laurence Sotin, Christophe Le Mouelic, Stephane Rodriguez, Sebastien Jaumann, Ralf Beyer, Ross A. Buratti, Bonnie J. Pitman, Karly Baines, Kevin H. Clark, Roger Nicholson, Phil TI Spectroscopy, morphometry, and photoclinometry of Titan's dunefields from Cassini/VIMS SO ICARUS LA English DT Article DE Titan; geological processes; satellites; atmospheres; spectroscopy ID LONGITUDINAL DUNES; LANDING SITE; SURFACE; VIMS; RADAR; DIVERSITY; MARS AB Fine-resolution (500 m/pixel) Cassini Visual and Infrared Mapping Spectrometer (VIMS) T20 observations of Titan resolve that moon's sand dunes. The spectral variability in some dune regions shows that there are sand-free interdune areas, wherein VIMS spectra reveal the exposed dune substrate. The interdunes from T20 are, variously, materials that correspond to the equatorial bright, 5-mu m-bright, and dark blue spectral units. Our observations show that an enigmatic "dark red" spectral unit seen in T5 in fact represents a macroscopic mixture with 5-mu m-bright material and dunes as its spectral endmembers. Looking more broadly, similar mixtures of varying amounts of dune and interdune units of varying composition can explain the spectral and albedo variability within the dark brown dune global spectral unit that is associated with dunes. The presence of interdunes indicates that Titan's dumefields are both mature and recently active. The spectrum of the dune endmember reveals the sand to be composed of less water ice than the rest of Titan; various organics are consistent with the dunes' measured reflectivity. We measure a mean dune spacing of 2.1 km, and find that the dunes are oriented on the average in an east-west direction, but angling up to 10 degrees from parallel to the equator in specific cases. Where no interdumes are present, we determine the height of one set of dunes photoclinometrically to be between 30 and 70 m. These results pave the way for future exploration and interpretation of Titan's sand dunes. (C) 2007 Elsevier Inc. All rights reserved. C1 [Barnes, Jason W.; Beyer, Ross A.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. [Brown, Robert H.] Univ Arizona, Dept Planetary Sci, Tucson, AZ 85721 USA. [Soderblom, Laurence] US Geol Survey, Flagstaff, AZ 85001 USA. [Sotin, Christophe; Buratti, Bonnie J.; Pitman, Karly; Baines, Kevin H.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Le Mouelic, Stephane] Univ Nantes, Lab Planetol & Geodynam, F-44322 Nantes 03, France. [Rodriguez, Sebastien] Ctr Orme Merisiers, DAPNIA Sap, Ctr Etud Saclay, Lab AIM, F-91191 Gif Sur Yvette, France. [Jaumann, Ralf] Inst Planetary Res, DLR, D-12489 Berlin, Germany. [Clark, Roger] US Geol Survey, Denver, CO 80225 USA. [Nicholson, Phil] Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. RP Barnes, JW (reprint author), NASA, Ames Res Ctr, M-S 244-30, Moffett Field, CA 94035 USA. EM jason@barnesos.net RI Barnes, Jason/B-1284-2009; Rodriguez, Sebastien/H-5902-2016; OI Barnes, Jason/0000-0002-7755-3530; Rodriguez, Sebastien/0000-0003-1219-0641; Beyer, Ross/0000-0003-4503-3335 NR 34 TC 68 Z9 68 U1 5 U2 8 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD MAY PY 2008 VL 195 IS 1 BP 400 EP 414 DI 10.1016/j.icarus.2007.12.006 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 295HR UT WOS:000255466100024 ER PT J AU Lunine, JI Elachi, C Wall, SD Janssen, MA Allison, MD Anderson, Y Boehmer, R Callahan, P Encrenaz, P Flamini, E Franceschetti, G Gim, Y Hamilton, G Hensley, S Johnson, WTK Kelleher, K Kirk, RL Lopes, RM Lorenz, R Muhleman, DO Orosei, R Ostro, SJ Paganelli, F Paillou, P Picardi, G Posa, F Radebaugh, J Roth, LE Seu, R Shaffer, S Soderblom, LA Stiles, B Stofan, ER Vetrella, S West, R Wood, CA Wye, L Zebker, H Alberti, G Karkoschka, E Rizk, B McFarlane, E See, C Kazeminejad, B AF Lunine, J. I. Elachi, C. Wall, S. D. Janssen, M. A. Allison, M. D. Anderson, Y. Boehmer, R. Callahan, P. Encrenaz, P. Flamini, E. Franceschetti, G. Gim, Y. Hamilton, G. Hensley, S. Johnson, W. T. K. Kelleher, K. Kirk, R. L. Lopes, R. M. Lorenz, R. Muhleman, D. O. Orosei, R. Ostro, S. J. Paganelli, F. Paillou, P. Picardi, G. Posa, F. Radebaugh, J. Roth, L. E. Seu, R. Shaffer, S. Soderblom, L. A. Stiles, B. Stofan, E. R. Vetrella, S. West, R. Wood, C. A. Wye, L. Zebker, H. Alberti, G. Karkoschka, E. Rizk, B. McFarlane, E. See, C. Kazeminejad, B. TI Titan's diverse landscapes as evidenced by Cassini RADAR's third and fourth looks at Titan SO ICARUS LA English DT Article DE Titan; radar observations; satellites; surfaces; geological processes; geophysics ID SURFACE; ORIGIN; MAPPER; WINDS; LAKES AB Cassini's third and fourth radar flybys, T7 and T8, covered diverse terrains in the high southern and equatorial latitudes, respectively. The T7 synthetic aperture radar (SAR) swath is somewhat more straightforward to understand in terms of a progressive poleward descent from a high, dissected, and partly hilly terrain down to a low flat plain with embayments and deposits suggestive of the past or even current presence of hydrocarbon liquids. The T8 swath is dominated by dunes likely made of organic solids, but also contain somewhat enigmatic, probably tectonic, features that may be partly buried or degraded by erosion or relaxation in a thin crust. The dark areas in T7 show no dume morphology, unlike the dark areas in T8, but are radiometrically warm like the dunes. The Huygens landing site lies on the edge of the T8 swath; correlation of the radar and Huygens DISR images allows accurate determination of its coordinates, and indicates that to the north of the landing site sit two large longitudinal dunes. Indeed, had the Huygens probe trajectory been just 10 km north of where it actually was, images of large sand dunes would have been returned in place of the fluvially dissected terrain actually seen-illustrating the strong diversity of Titan's landscapes even at local scales. (C) 2008 Elsevier Inc. All rights reserved. C1 [Lunine, J. I.; Lorenz, R.; Karkoschka, E.; Rizk, B.; McFarlane, E.] Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. [Lunine, J. I.] INAF IFSI, I-00133 Rome, Italy. [Lunine, J. I.; Elachi, C.; Wall, S. D.; Janssen, M. A.; Anderson, Y.; Boehmer, R.; Callahan, P.; Hamilton, G.; Hensley, S.; Johnson, W. T. K.; Kelleher, K.; Lopes, R. M.; Ostro, S. J.; Paganelli, F.; Roth, L. E.; West, R.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Allison, M. D.] NASA, Goddard Inst Space Studies, New York, NY 10025 USA. [Encrenaz, P.] Observ Paris, F-92195 Meudon, France. [Flamini, E.] Agenzia Spaziale Italiana, I-00131 Rome, Italy. [Franceschetti, G.] Fac Ingn, I-80125 Naples, Italy. [Kirk, R. L.] US Geol Survey, Flagstaff, AZ 86001 USA. [Muhleman, D. O.] CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA. [Orosei, R.] CNR, IASF, I-00133 Rome, Italy. [Paillou, P.] Observ Aquitain Sci Univers, UMR 5804, F-33270 Floirac, France. [Picardi, G.] Univ Roma La Sapienza, I-00184 Rome, Italy. [Posa, F.] Politecn Bari, Dip Interateneo Fis, I-70126 Bari, Italy. [Posa, F.] Politecn Bari, INFM, I-70126 Bari, Italy. [Radebaugh, J.] Brigham Young Univ, Dept Geol Sci, Provo, UT 84602 USA. [Stofan, E. R.] Proxemy Res, Rectortown, VA 20140 USA. [Wood, C. A.] Planetary Sci Inst, Tucson, AZ 85719 USA. [Wye, L.; Zebker, H.] Stanford Univ, Stanford, CA 94305 USA. [Alberti, G.] CORISTA, I-80125 Naples, Italy. [Kazeminejad, B.] German Space Operat Ctr, DLR, D-82234 Wessling, Germany. RP Lunine, JI (reprint author), Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. EM jlunine@lpl.arizona.edu RI Lorenz, Ralph/B-8759-2016; Lopes, Rosaly/D-1608-2016 OI Lorenz, Ralph/0000-0001-8528-4644; Lopes, Rosaly/0000-0002-7928-3167 NR 36 TC 36 Z9 36 U1 0 U2 2 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 EI 1090-2643 J9 ICARUS JI Icarus PD MAY PY 2008 VL 195 IS 1 BP 415 EP 433 DI 10.1016/j.icarus.2007.12.022 PG 19 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 295HR UT WOS:000255466100025 ER PT J AU Rietmeijer, FJM Pun, A Kimura, Y Nuth, JA AF Rietmeijer, Frans J. M. Pun, Aurora Kimura, Yuki Nuth, Joseph A., III TI A refractory Ca-SiO-H(2)-O(2) vapor condensation experiment with implications for calciosilica dust transforming to silicate and carbonate minerals SO ICARUS LA English DT Article DE Comets; dust; Disks; Mineralogy; Experimental techniques ID METASTABLE EUTECTIC CONDENSATION; SOLAR NEBULA; MAGNESIUM SILICATES; CIRCUMSTELLAR DUST; SOLID CONDENSATION; ALLENDE METEORITE; COMET 81P/WILD-2; RICH INCLUSIONS; DEEP IMPACT; GRAINS AB Condensates produced in a laboratory condensation experiment of a refractory Ca-SiO-H(2)-O(2) vapor define four specific and predictable deep metastable eutectic calciosilica compositions. The condensed nanograins are amorphous solids, including those with the stoichiometric CaSiO(3) pyroxene composition. In evolving dust-condensing astronomical environments they will be highly suitable precursors for thermally supported, dust-aging reactions whereby the condensates form more complex refractory silicates, e.g., diopside and wollastonite, and calcite and dolomite carbonates. This kinetically controlled condensation experiment shows how the aging of amorphous refractory. condensates could produce the same minerals that are thought to require high-temperature equilibrium condensation. We submit that evidence for this thermal annealing of dust will be the astronomical detection of silica (amorphous or crystalline) that is the common, predicted, by-product of most of these reactions. (C) 2007 Elsevier Inc. All rights reserved. C1 [Rietmeijer, Frans J. M.; Pun, Aurora] Univ New Mexico, Dept Earth & Planetary Sci, Albuquerque, NM 87131 USA. [Kimura, Yuki] Ritsumeikan Univ, Dept Phys, Lab Nano Stuct Sci, Kusatsu, Shiga 5258577, Japan. [Nuth, Joseph A., III] NASA, Goddard Space Flight Ctr, Solar Syst Explorat Div, Astrochem Lab, Greenbelt, MD 20771 USA. RP Rietmeijer, FJM (reprint author), Univ New Mexico, Dept Earth & Planetary Sci, MSC03-2040, Albuquerque, NM 87131 USA. EM fransjmr@unm.edu RI Nuth, Joseph/E-7085-2012; Kimura, Yuki/J-9635-2014 OI Kimura, Yuki/0000-0002-9218-7663 NR 75 TC 13 Z9 13 U1 0 U2 2 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0019-1035 J9 ICARUS JI Icarus PD MAY PY 2008 VL 195 IS 1 BP 493 EP 503 DI 10.1016/j.icarus.2007.11.022 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 295HR UT WOS:000255466100030 ER PT J AU Neudeck, PG Spry, DJ Chen, LY Beheim, GM Okojie, RS Chang, CW Meredith, RD Ferrier, TL Evans, LJ Krasowski, MJ Prokop, NF AF Neudeck, Philip G. Spry, David J. Chen, Liang-Yu Beheim, Glenn M. Okojie, Robert S. Chang, Carl W. Meredith, Roger D. Ferrier, Terry L. Evans, Laura J. Krasowski, Michael J. Prokop, Norman F. TI Stable electrical operation of 6H-SiC JFETs and ICs for thousands of hours at 500 degrees C SO IEEE ELECTRON DEVICE LETTERS LA English DT Article DE high-temperature techniques; integrated circuit (IC) reliability; JFET ICs; junction field-effect transistors (JFETs); silicon compounds AB The fabrication and testing of the first semiconductor transistors and small-scale integrated circuits (ICs) to achieve up to 3000 It of stable electrical operation at 500 degrees C in air ambient is reported. These devices are based on an epitaxial 6H-SiC junction field-effect transistor process that successfully integrated high-temperature ohmic contacts, dielectric passivation, and ceramic packaging. Important device and circuit parameters exhibited less than 10% of change over the course of the 500 degrees C operational testing. These results establish a new technology foundation for realizing durable 500 degrees C ICs for combustion-engine sensing and control, deep-well drilling, and other harsh-environment applications. C1 [Neudeck, Philip G.; Spry, David J.; Chen, Liang-Yu] NASA, Glenn Res Ctr, Ohio Aerosp Inst, Cleveland, OH 44135 USA. [Chang, Carl W.] ASRC Aerosp Corp, Cleveland, OH 44135 USA. RP Neudeck, PG (reprint author), NASA, Glenn Res Ctr, Ohio Aerosp Inst, Cleveland, OH 44135 USA. EM Neudeck@nasa.gov NR 12 TC 50 Z9 51 U1 1 U2 7 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0741-3106 J9 IEEE ELECTR DEVICE L JI IEEE Electron Device Lett. PD MAY PY 2008 VL 29 IS 5 BP 456 EP 459 DI 10.1109/LED.2008.919787 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA 293EG UT WOS:000255317400012 ER PT J AU Fox, BP Schneider, ZV Simmons-Potter, K Thomes, WJ Meister, DC Bambha, RP Kliner, DAV AF Fox, Brian P. Schneider, Zachary V. Simmons-Potter, Kelly Thomes, William. J., Jr. Meister, Dorothy C. Bambha, Ray P. Kliner, Dahv A. V. TI Spectrally resolved transmission loss in gamma irradiated Yb-doped optical fibers SO IEEE JOURNAL OF QUANTUM ELECTRONICS LA English DT Article DE gamma irradiation; photodarkening; radiation effects; radiation-induced absorption; rare-earth doped fibers; Yb-doped fibers ID POWER; LASER; GENERATION; AMPLIFIERS; DEFECTS; GLASSES AB Yb(3+)-doped silicate fibers are commonly employed in optical systems utilizing fiber lasers and amplifiers. Deployment of such materials and systems in space-based and other adverse radiation environments requires knowledge of their response to fluxes of ionizing radiation. This paper reports the results of gamma radiation exposures on a suite of passive, modern, highly Yb(3+)-doped aluminosilicate fibers. Of interest are the effects of total dose,and dose rate as well as the development of radiation-induced absorption across a broad spectral window (1.0-1.7 mu m). Results indicate that these fibers exhibit reasonable radiation resistance to gamma exposures typical of a five-year low-Earth-orbit environment. Maximum transmittance losses of less than 10% in the 1.0-1.7 mu m spectral region for total gamma exposures of 2-5 krad (Si) were observed. In addition, it was found that the dependence of transmittance on radiation dose generally followed a power law that was dependent on,dose rate. C1 [Fox, Brian P.; Schneider, Zachary V.; Simmons-Potter, Kelly] Univ Arizona, Tucson, AZ USA. [Thomes, William. J., Jr.] Sandia Natl Labs, Albuquerque, NM 87185 USA. [Thomes, William. J., Jr.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Meister, Dorothy C.] Sandia Natl Labs, Albuquerque, NM 87123 USA. [Bambha, Ray P.; Kliner, Dahv A. V.] Sandia Natl Labs, Livermore, CA 94550 USA. RP Fox, BP (reprint author), Univ Arizona, Tucson, AZ USA. EM bpf@e-mail.arizona.edu; zvs@e-mail.arizona.edu; kspotter@ece.arizona.edu; joe.thomes@nasa.gov; demeist@sandia.gov NR 23 TC 13 Z9 14 U1 0 U2 12 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0018-9197 J9 IEEE J QUANTUM ELECT JI IEEE J. Quantum Electron. PD MAY-JUN PY 2008 VL 44 IS 5-6 BP 581 EP 586 DI 10.1109/JQE.2008.919873 PG 6 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 312VW UT WOS:000256701500024 ER PT J AU Moision, B Farr, W AF Moision, Bruce Farr, William TI Communication limits due to photon detector jitter SO IEEE PHOTONICS TECHNOLOGY LETTERS LA English DT Article DE capacity; jitter; optical communication; single photon detector AB Detector jitter, the random delay from the time a photon is incident on a single-photon-counting detector (SPD) to the time an electrical pulse is produced in response to that photon, is characterized for a number of SPDs. The jitter is modeled as a weighted sum of Gaussians. The performance in detector jitter is measured by determining the capacity of a communications channel utilizing a given detector. It is observed that the loss, measured as the ratio of the signal power required to achieve a specified capacity in the presence of jitter to that in the absence of jitter, goes as the square of the normalized jitter standard deviation (the standard deviation of the jitter in slotwidths). The loss is small when the normalized jitter is less than one, and becomes significant beyond that point. This loss must be taken into account when evaluating detectors for very high throughput channels. C1 [Moision, Bruce; Farr, William] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Moision, B (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Bruce.E.Moision@jpl.nasa.gov; William.H.Farr@jpl.nasa.gov NR 5 TC 12 Z9 12 U1 1 U2 8 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 1041-1135 J9 IEEE PHOTONIC TECH L JI IEEE Photonics Technol. Lett. PD MAY-JUN PY 2008 VL 20 IS 9-12 BP 715 EP 717 DI 10.1109/LPT.2008.919451 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 316QZ UT WOS:000256966100017 ER PT J AU Bell, LD Tripathi, N Grandusky, JR Jindal, V Shahedipour-Sandvik, FS AF Bell, L. Douglas Tripathi, Neeraj Grandusky, J. R. Jindal, Vibhu Shahedipour-Sandvik, F. Shadi TI III-nitride heterostructure layered tunnel barriers for a tunable hyperspectral detector SO IEEE SENSORS JOURNAL LA English DT Article DE dielectric films; transducers; tunneling; ultraviolet detectors ID LIGHT-EMITTING-DIODES; INTERNAL PHOTOEMISSION; IMAGING SPECTROMETER; SPECTROSCOPY; GAN AB We report on the fabrication and characterization of III-nitride layered tunnel barriers with applications for a new type of tunable hyperspectral imaging detector with intrinsically hyperspectral pixels. This would enable each pixel to be individually tunable in real-time through a range of wavelengths, with the number and width of spectral channels being dynamically adjustable. Shape-engineered electron barriers fabricated from III-nitride heterostructures allow barrier height to be varied by application of a voltage. A spectroscopy of photon wavelength is enabled via the collection of photoexcited electrons across this barrier. The device is envisioned for tunable detection of ultraviolet through infrared wavelengths. C1 [Bell, L. Douglas] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Tripathi, Neeraj; Grandusky, J. R.; Jindal, Vibhu; Shahedipour-Sandvik, F. Shadi] SUNY Albany, Coll Nanoscale Sci & Engn, Albany, NY 12203 USA. RP Bell, LD (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM lbell@mail.jpl.nasa.gov; ntripathi@uamail.albany.edu; jgrandusky@uamail.albany.edu; vjindal@uamail.albany.edu; sshahedipour@uamail.albany.edu FU Jet Propulsion Laboratory, California Institute of Technology FX Manuscript received January 7, 2008; revised February 22, 2008; accepted February 26, 2008. This work was supported in part by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with National Aeronautics and Space Administration. The associate editor coordinating the review of this paper and approving it for publication was Dr. Janet Jensen. NR 20 TC 3 Z9 3 U1 0 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 1530-437X J9 IEEE SENS J JI IEEE Sens. J. PD MAY-JUN PY 2008 VL 8 IS 5-6 BP 724 EP 729 DI 10.1109/JSEN.2008.923180 PG 6 WC Engineering, Electrical & Electronic; Instruments & Instrumentation; Physics, Applied SC Engineering; Instruments & Instrumentation; Physics GA 342CW UT WOS:000258763200043 ER PT J AU Mueller, CH Lee, RQ Romanofsky, RR Kory, CL Lambert, KM Van Keuls, FW Miranda, FA AF Mueller, Carl H. Lee, Richard Q. Romanofsky, Robert R. Kory, Carol L. Lambert, Kevin M. Van Keuls, Frederick W. Miranda, Felix A. TI Small-size X-band active integrated antenna with feedback loop SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION LA English DT Article DE active integrated antenna (AIA); oscillator; phase noise; microstrip ID LOCKED OSCILLATOR ARRAYS; MICROSTRIP ANTENNAS; PATCH ANTENNA AB A small-sized active integrated antenna (AIA), consisting of a transmission feedback oscillator loaded with a microstrip antenna is presented in this paper. The oscillator antenna, which consists of a NEC super low noise high frequency field effect transistor (HF FET) integrated into the center of a segmented patch antenna, was designed for X-band at 8.50 GHz, and occupies a 5 x 6 mm(2) area. The active integrated antenna demonstrates stable oscillations and excellent radiation patterns at X-band design frequencies. When biased using a single 1.5 volt battery connected between the source and drain and with the gate terminal open, the antenna effective isotropic radiated power (EIRP) and direct current (DC)-to-radiated radio frequency (RF) conversion efficiency are +11.2 dBm and 10.5%, respectively. The radiated power level and directivity are +4.5 dBm and 6.7 dBi, respectively. The phase noise at 100 kHz offset from the carrier is -87.5 dBc/Hz, which is a notable improvement over existing AIA designs. The AIA features compact size and simple geometry, yet provides radiated power levels and radiation efficiencies that are comparable to values typically obtained using circuits that occupy larger areas, and use thicker substrates with much lower dielectric constant values. C1 [Mueller, Carl H.; Kory, Carol L.; Lambert, Kevin M.] QinetiQ N America Operat, Miss Solut Grp, Cleveland, OH 44135 USA. [Lee, Richard Q.; Romanofsky, Robert R.; Miranda, Felix A.] NASA, Glenn Res Ctr, Commun Div, Antenna Microwave & Opt Syst Branch, Cleveland, OH 44135 USA. [Van Keuls, Frederick W.] Ohio Aerosp Inst, Cleveland, OH USA. RP Mueller, CH (reprint author), QinetiQ N America Operat, Miss Solut Grp, Cleveland, OH 44135 USA. EM Felix.A.Miranda@nasa.gov NR 20 TC 12 Z9 12 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0018-926X J9 IEEE T ANTENN PROPAG JI IEEE Trans. Antennas Propag. PD MAY PY 2008 VL 56 IS 5 BP 1236 EP 1241 DI 10.1109/TAP.2008.922628 PG 6 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 302QW UT WOS:000255985400004 ER PT J AU Llombart, N Neto, A Gerini, G Bonnedal, M De Maagt, P AF Llombart, Nuria Neto, Andrea Gerini, Giampiero Bonnedal, Magnus De Maagt, Peter TI Leaky wave enhanced feed arrays for the improvement of the edge of coverage gain in multibeam reflector antennas SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION LA English DT Article DE leaky wave antennas; leaky waves; reflector antenna feeds; reflector antennas AB The performance of multibeam focal plane arrays feeding a single aperture is usually reduced due to conflicting requirements on the feed elements. Dense packing is usually required to minimize the beam separation, while typically large feed apertures are needed to provide the high feed directivity to reduce spillover losses from the reflector. In this paper the use of dielectric super-layers to shape the radiation pattern of each feed is demonstrated. The shaping is obtained by exciting, according to design, a pair of TE/TM leaky waves. The spillover from the reflector is reduced without physically increasing the dimensions of each single element aperture. A prototype of a feed array composed of 19 waveguides arranged in a hexagonal lattice was designed, manufactured and tested. The measured embedded patterns provided an increase of the edge of coverage gain, with respect to the free space case, of at least 0.6 dB in an operating bandwidth (BW) of approximate to 12%. Moreover when reactive loading of adjacent feeds is adopted the increase in the edge of coverage with respect to the free space case was demonstrated to be larger than 1.6 dB over a 3% BW. C1 [Llombart, Nuria; Neto, Andrea; Gerini, Giampiero] Netherlands Org Appl Sci Res TNO, NL-2597 AK The Hague, Netherlands. [Bonnedal, Magnus] Saab Ericsson Space, Gothenburg, Sweden. [De Maagt, Peter] European Space Agcy, Div Electomagnet, NL-2200 AG Noordwijk, Netherlands. RP Llombart, N (reprint author), CALTECH, Jet Prop Lab, SWAT Grp, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM nuria.llombartjuan@tno.nl; andrea.neto@tno.nl; giampiero.gerini@tno.nl; magnus.bonnedal@space.se; Peter.de.Maagt@esa.int NR 19 TC 26 Z9 26 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-926X J9 IEEE T ANTENN PROPAG JI IEEE Trans. Antennas Propag. PD MAY PY 2008 VL 56 IS 5 BP 1280 EP 1291 DI 10.1109/TAP.2008.922680 PG 12 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 302QW UT WOS:000255985400009 ER PT J AU Li, JJ Ouellette, AL Giovangrandi, L Cooper, DE Ricco, AJ Kovacs, GTA AF Li, Janice J. Ouellette, Amy L. Giovangrandi, Laurent Cooper, David E. Ricco, Antonio J. Kovacs, Gregory T. A. TI Optical scanner for immunoassays with up-converting phosphorescent labels SO IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING LA English DT Article DE cytokine; immunoassay; lateral flow; microfluidics; optical scanner; up-converting phosphor (UCP) ID ACUTE CORONARY SYNDROMES; CARDIAC TROPONIN-T; C-REACTIVE PROTEIN; NATRIURETIC PEPTIDE; TNF-ALPHA; AUTOMATED IMMUNOASSAY; HELICOBACTER-PYLORI; PARATHYROID-HORMONE; LATERAL-FLOW; ASSAY AB A 2-D optical scanner was developed for the imaging and quantification of up-converting phosphor (UCP) labels in immunoassays. With resolution better than 500 mu m, a scan rate of 0.4 mm/s, and a 1-2% coefficient of variation for repeatability, this scanner achieved a detection limit of fewer than 100 UCP particles in an 8.8 x 10(4) mu m(2) area and a dynamic range that covered more than three orders of magnitude. Utilizing this scanner, a microfluidic chip immunoassay for the cytokine interferon-gamma (IFN-gamma) was developed: concentrations as low as 3 pM (50 pg/mL) were detected from 100 mu L samples with a total assay time of under an hour, including the 8 min readout. For this UCP-based assay, 2-D images of the capture antibody lines were scanned, image processing techniques were employed to extract the UCP emission signals, a response curve that spanned 3-600 pM IFN-gamma was generated, and a five-parameter logistic mathematical model was fitted to the data for determination of unknown IFN-gamma concentrations. Relative to common single-point or 1-D scanning optical measurements, our results suggest that a simple 2-D imaging system can speed assay development, reduce errors, and improve accuracy by characterizing the spatial distribution and uniformity of surface-captured optical labels as a function of assay conditions and device parameters. C1 [Ouellette, Amy L.; Giovangrandi, Laurent; Kovacs, Gregory T. A.] Stanford Univ, Dept Elect Engn, Stanford, CA 94305 USA. [Ricco, Antonio J.] NASA, Ames Res Ctr, Small Spacecraft Div, Moffett Field, CA 94035 USA. [Cooper, David E.] SRI Int, Menlo Pk, CA 94025 USA. RP Kovacs, GTA (reprint author), Stanford Univ, Dept Elect Engn, Stanford, CA 94305 USA. EM kovacs@cis.stanford.edu RI Ricco, Antonio/A-5273-2010; OI Ricco, Antonio/0000-0002-2355-4984 NR 61 TC 24 Z9 25 U1 1 U2 8 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9294 J9 IEEE T BIO-MED ENG JI IEEE Trans. Biomed. Eng. PD MAY PY 2008 VL 55 IS 5 BP 1560 EP 1571 DI 10.1109/TBME.2007.914674 PG 12 WC Engineering, Biomedical SC Engineering GA 290US UT WOS:000255148600011 PM 18440902 ER PT J AU Liao, L Meneghini, R Tian, L Heymsfield, GA AF Liao, Liang Meneghini, Robert Tian, Lin Heymsfield, Gerald A. TI Retrieval of snow and rain from combined X- and W-band airborne radar measurements SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE airborne radar; attenuation; particle size distribution; radar retrieval; rain; snow ID DUAL-WAVELENGTH RADAR; PRECIPITATION; PARAMETERS AB Two independent airborne dual-wavelength techniques, based on nadir measurements of radar reflectivity factors and Doppler velocities, respectively, are investigated with respect to their capability of estimating microphysical properties of Hydrometeors. The data used to investigate the methods are taken from the ER-2 Doppler radar (X-band) and Cloud Radar System (W-band) airborne Doppler radars during the Cirrus Regional Study of Tropical Anvils and Cirrus Layers-Florida Area Cirrus Experiment campaign in 2002. Validity is assessed by the degree to which the methods produce consistent retrievals of the microphysics. For deriving snow parameters, the reflectivity-based technique has a clear advantage over the Doppler-velocity-based approach because of the large dynamic range in the dual-frequency ratio (DFR) with respect to the median diameter Do and the fact that the difference in mean Doppler velocity at the two frequencies, i.e., the differential Doppler velocity (DDV), in snow is small relative to the measurement errors and is often not uniquely related to Do. The DFR and DDV can also be used to independently derive Do in rain. At W-band, the DFR-based algorithms are highly sensitive to attenuation from rain, cloud water, and water vapor. Thus, the retrieval algorithms depend on various assumptions regarding these components, whereas the DDV-based approach is unaffected by attenuation. In view of the difficulties and ambiguities associated with the attenuation correction at W-band, the DDV approach in rain is more straightforward and potentially more accurate than the DFR method. C1 [Liao, Liang; Tian, Lin] Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Catonsville, MD 21250 USA. [Meneghini, Robert] NASA, Goddard Space Flight Ctr, Instrument Sci Branch, Greenbelt, MD 20771 USA. [Heymsfield, Gerald A.] NASA, Goddard Space Flight Ctr, Mesoscale Atmospher Proc Branch, Greenbelt, MD 20771 USA. RP Liao, L (reprint author), Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Catonsville, MD 21250 USA. EM Liang.Liao-1@nasa.gov NR 23 TC 14 Z9 15 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0196-2892 EI 1558-0644 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD MAY PY 2008 VL 46 IS 5 BP 1514 EP 1524 DI 10.1109/TGRS.2008.916079 PG 11 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 291UQ UT WOS:000255222800021 ER PT J AU Glasgow, JM Thomas, G Pudenz, E Cabrol, N Wettergreen, D Coppin, P AF Glasgow, Justin M. Thomas, Geb Pudenz, Erin Cabrol, Nathalie Wettergreen, David Coppin, Peter TI Optimizing information value: Improving rover sensor data collection SO IEEE TRANSACTIONS ON SYSTEMS MAN AND CYBERNETICS PART A-SYSTEMS AND HUMANS LA English DT Article DE human computer interaction; images; robot; search ID SITUATION AWARENESS; SEARCH STRATEGY; OPTIMUM SPEED; VISUAL-SEARCH; ROBOT; INTERFACES; DESIGN AB Robotic exploration is an excellent method for obtaining information about sites too dangerous for people to explore. The operator's understanding of the environment depends on the rover returning useful information. Robotic mission bandwidth is frequently constrained, limiting the amount of information the rover can return. This paper explores the tradeoff between information and bandwidth based on two years of observations during a robotic astrobiology field study. The developed theory begins by analyzing the search task conducted by robot operators. This analysis leads to an information optimization model. Important parameters in the model include the value associated with detecting a target, the probability of locating a target, and the bandwidth required to collect the information from the environment. Optimizing the information return between regions creates an image and provides the necessary information while reducing bandwidth. Application of the model to the analyzed field study results in an optimized image that requires 48.3 % less bandwidth to collect. The model also predicts several data collection patterns that could serve as the basis of data collection templates for improving mission effectiveness. The developed optimization model reduces the bandwidth necessary to collect information, thus aiding missions in collecting more information from the environment. C1 [Glasgow, Justin M.; Thomas, Geb; Pudenz, Erin] Univ Iowa, Dept Mech & Ind Engn, Iowa City, IA 52242 USA. [Cabrol, Nathalie] SETI Inst, Mountain View, CA 94043 USA. [Cabrol, Nathalie] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. [Wettergreen, David; Coppin, Peter] Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. RP Glasgow, JM (reprint author), Univ Iowa, Dept Mech & Ind Engn, Iowa City, IA 52242 USA. EM geb-thomas@uiowa.edu; ncabrol@mail.arc.nasa.gov NR 43 TC 7 Z9 7 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1083-4427 EI 1558-2426 J9 IEEE T SYST MAN CY A JI IEEE Trans. Syst. Man Cybern. Paart A-Syst. Hum. PD MAY PY 2008 VL 38 IS 3 BP 593 EP 604 DI 10.1109/TSMCA.2008.918614 PG 12 WC Computer Science, Cybernetics; Computer Science, Theory & Methods SC Computer Science GA 333VZ UT WOS:000258183000009 ER PT J AU Bozz, G Mosca, HO del Grosso, MF AF Bozz, Guillermo Mosca, Hugo O. del Grosso, Mariela F. TI Energy of formation, lattice parameter and bulk modulus of (Ni,X)Ti alloys with X = Fe, Pd, Pt, Au, Al, Cu, Zr, Hf SO INTERMETALLICS LA English DT Article DE ternary alloy systems; alloy design; site occupancy; simulations, atomistic; shape memory alloy applications ID SHAPE-MEMORY ALLOYS; HIGH-TEMPERATURE APPLICATIONS; TI-NI-PD; MARTENSITIC-TRANSFORMATION; THIN-FILMS; SPUTTER-DEPOSITION; SITE PREFERENCE; ATOM LOCATION; 3RD ELEMENT; PHASE AB An analysis of the ternary 'bridge' Ni50-yXyTi50 alloys with X = Fe, Pd, Pt, Au, Al, Cu, Zr, and Hf was performed using the BFS method for alloys. The lattice parameter, bulk modulus and energy of formation were determined for all the intermediate states in the (B2) transition NiTi to XTi. (C) 2008 Elsevier Ltd. All rights reserved. C1 [Bozz, Guillermo] Ohio Aerosp Inst, Cleveland, OH 44142 USA. [Bozz, Guillermo] NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. [Mosca, Hugo O.; del Grosso, Mariela F.] Comis Nacl Energia Atom, San Martin, Argentina. [Mosca, Hugo O.; del Grosso, Mariela F.] FRG Pacheco, UTN, GCMM, Gral Pacheco, Argentina. RP Bozz, G (reprint author), Ohio Aerosp Inst, 22800 Cedar Point Rd, Cleveland, OH 44142 USA. EM guillermobozzolo@oai.org NR 49 TC 13 Z9 14 U1 5 U2 21 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0966-9795 EI 1879-0216 J9 INTERMETALLICS JI Intermetallics PD MAY PY 2008 VL 16 IS 5 BP 668 EP 675 DI 10.1016/j.intermet.2008.02.003 PG 8 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 302XZ UT WOS:000256004700011 ER PT J AU Wu, LG Wang, B Braun, SA AF Wu, Liguang Bin Wang Braun, Scott A. TI Implications of tropical cyclone power dissipation index SO INTERNATIONAL JOURNAL OF CLIMATOLOGY LA English DT Article DE tropical cyclone; power dissipation index; average intensity; climate change ID WESTERN NORTH PACIFIC; HURRICANE INTENSITIES; CLIMATE; INCREASE; TRENDS; PRECIPITATION; IMPACT; MODEL AB Upward trends in the power dissipation index (PDI) in the North Atlantic (NA) and western North Pacific (WNP) basins and increases in the number and proportion of intense hurricanes (categories 4 and 5) in all tropical cyclone basins have been reported in recent studies. These changes have been arguably viewed as evidence of the responses of tropical cyclone intensity to the increasing tropical sea surface temperature (SST) over the past 30 years. Using the historical best-track datasets from 1975 to 2004, how the annual frequency, lifetime and intensity of tropical cyclones contribute to the changes in the annual accumulated PDI is examined. As the SST warmed in the NA, WNP and eastern North Pacific (ENP) basins over the past 30 years, the annual accumulated PDI trended upward significantly only in the NA basin, where the decreased vertical wind shear and warming ocean surface may have allowed more storms to form and to form earlier or dissipate later, increasing the lifetime and annual frequency of tropical cyclones. The moderate increase in the annual accumulated PDI in the WNP basin was primarily due to the significant increase in the average intensity. There are no significant trends in the accumulated PDI, average intensity, average lifetime, and annual frequency in the ENP basin. Copyright (c) 2007 Royal Meteorological Society. C1 [Wu, Liguang; Braun, Scott A.] NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20071 USA. [Bin Wang] Univ Hawaii, Dept Meteorol, Honolulu, HI 96822 USA. [Wu, Liguang] Univ Maryland Baltimore Cty, Goddard Earth & Technol Ctr, Baltimore, MD 21228 USA. RP Wu, LG (reprint author), NASA, Goddard Space Flight Ctr, Atmospheres Lab, Code 613-1, Greenbelt, MD 20071 USA. NR 21 TC 31 Z9 36 U1 1 U2 12 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0899-8418 J9 INT J CLIMATOL JI Int. J. Climatol. PD MAY PY 2008 VL 28 IS 6 BP 727 EP 731 DI 10.1002/joc.1573 PG 5 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 308AQ UT WOS:000256361100002 ER PT J AU Callegan, RP Nobre, MF McTernan, PM Battista, JR Navarro-Gonzalez, R Mckay, CP da Costa, MS Rainey, FA AF Callegan, Ryan P. Nobre, M. Fernanda McTernan, Patrick M. Battista, John R. Navarro-Gonzalez, Rafael Mckay, Christopher P. da Costa, Milton S. Rainey, Fred A. TI Description of four novel psychrophilic, ionizing radiation-sensitive Deinococcus species from alpine environments SO INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY LA English DT Article ID SP-NOV.; DEOXYRIBONUCLEIC-ACID; RESISTANT BACTERIA; FAM-NOV; DESERT; TEMPERATURE; PROPOSAL; THERMUS AB Five psychrophilic bacterial strains were isolated from soil samples collected above the treeline of alpine environments. Phylogenetic analysis based on 16S rRNA gene sequences indicated that these organisms represent four novel species of the genus Deinococcus; levels of sequence similarity to the type strains of recognized Deinococcus species were in the range 89.3-94.7%. Strains PO-04-20-132(T), PO-04-20-144, PO-04-19-125(T), ME-04-01-32(T) and ME-04-04-52(T) grew aerobically, with optimum growth at 10 degrees C and at pH 6-9. The major respiratory menaquinone was MK-8. The fatty acid profiles of strains PO-04-20-132(T), PO-04-20-144, PO-04-19-125(T) and ME-04-01-32(T) were dominated by 16:1 omega 7c, 17:0 iso and 15:1 omega 6c, whereas 16:1 omega 7c, 17:0 cyclo and 16:0 predominated in strain ME-04-04-52(T). The DNA G + C contents of strains PO-04-20-132(T), PO-04-19-125(T), ME-04-01-32(T) and ME-04-04-52(T) were 63.2, 63.1, 65.9 and 62.6 mol%, respectively. Strains PO-04-20-132(T), PO-04-19-125(T), ME-04-01-32(T) and ME-04-04-52(T) had gamma radiation D-10 (dose required to reduce the bacterial population by 10-fold) values of <= 4 kGy. These four strains showed sensitivity to UV radiation and extended desiccation as compared with Deinococcus radiodurans. On the basis of the phylogenetic analyses, and chemotaxonomic and phenotypic data, it is proposed that strains PO-04-20-132(T) (=LMG 24019(T) =NRRL B-41950(T) Deinococcus radiomollis sp. nov.), PO-04-19-125(T) (=LMG 24282(T) =NRRL B-41949(T) Deinococcus claudionis sp. nov.), ME-04-01-32(T) (=LMG 24022(T) =NRRL B-41947(T) Deinococcus altitudinis sp. nov.) and ME-04-04-52(T) (=LMG 24283(T) =NRRL B-41948(T) Deinococcus alpinitundrae sp. nov.) represent the type strains of four novel species of the genus Deinococcus. C1 [Callegan, Ryan P.; McTernan, Patrick M.; Battista, John R.; Rainey, Fred A.] Louisiana State Univ, Dept Biol Sci, Baton Rouge, LA 70803 USA. [Nobre, M. Fernanda] Univ Coimbra, Dept Zool, P-3004517 Coimbra, Portugal. [Navarro-Gonzalez, Rafael] Univ Nacl Autonoma Mexico, Inst Ciencias Nucl, Lab Quim Plasmas & Estudios Planetarios, Mexico City 04510, DF, Mexico. [Mckay, Christopher P.] NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. [da Costa, Milton S.] Univ Coimbra, Dept Bioquim, P-3004517 Coimbra, Portugal. [da Costa, Milton S.] Univ Coimbra, Ctr Neurociencias & Biol Celular, P-3004517 Coimbra, Portugal. RP Rainey, FA (reprint author), Louisiana State Univ, Dept Biol Sci, Baton Rouge, LA 70803 USA. EM frainey@lsu.edu RI Gonzalez, Rafael/D-1748-2009; Rainey, Fred/C-8767-2013; OI Rainey, Fred/0000-0001-9129-6844; da Costa, Milton/0000-0003-4027-4412 NR 22 TC 47 Z9 47 U1 0 U2 10 PU SOC GENERAL MICROBIOLOGY PI READING PA MARLBOROUGH HOUSE, BASINGSTOKE RD, SPENCERS WOODS, READING RG7 1AG, BERKS, ENGLAND SN 1466-5026 J9 INT J SYST EVOL MICR JI Int. J. Syst. Evol. Microbiol. PD MAY PY 2008 VL 58 BP 1252 EP 1258 DI 10.1099/ijs.0.65405-0 PN 5 PG 7 WC Microbiology SC Microbiology GA 304SN UT WOS:000256129500036 PM 18450723 ER PT J AU Green, SJ Blackford, C Bucki, P Jahnke, LL Prufert-Bebout, L AF Green, Stefan J. Blackford, Cameron Bucki, Patricia Jahnke, Linda L. Prufert-Bebout, Lee TI A salinity and sulfate manipulation of hypersaline microbial mats reveals stasis in the cyanobacterial community structure SO ISME JOURNAL LA English DT Article DE cyanobacteria; Microcoleus chthonoplastes; Oscillatoriales; salinity; sulfate ID 16S RIBOSOMAL-RNA; MICROCOLEUS-CHTHONOPLASTES; BACTERIAL DIVERSITY; PETROLEUM COMPOUNDS; ATMOSPHERIC OXYGEN; PHOTOSYNTHESIS; REDUCTION; GRADIENT; GENES; MICROELECTRODE AB The cyanobacterial community structure and composition of hypersaline mats were characterized in an experiment in which native salinity and sulfate levels were modified. Over the course of approximately 1 year, microbial mats collected from Guerrero Negro (Baja, California Sur, Mexico) were equilibrated to lowered salinity (to 35 p.p.t.) and lowered sulfate (below 1 mM) conditions. The structure and composition of the cyanobacterial community in the top 5 mm of these mats were examined using a multifaceted cultivation-independent molecular approach. Overall, the relative abundance of cyanobacteria-roughly 20% of the total bacterial community, as assayed with a PCR-based methodology-was not significantly affected by these manipulations. Furthermore, the mat cyanobacterial community was only modestly influenced by the dramatic changes in sulfate and salinity, and the dominant cyanobacteria were unaffected. Community composition analyses confirmed the dominant presence of the cosmopolitan cyanobacterium Microcoleus chthonoplastes, but also revealed the dominance of another Oscillatorian cyanobacterial group, also detected in other hypersaline microbial mats. Cyanobacterial populations increasing in relative abundance under the modified salinity and sulfate conditions were found to be most closely related to other hypersaline microbial mat organisms, suggesting that the development of these mats under native conditions precludes the development of organisms better suited to the less restrictive experimental conditions. These results also indicate that within a significant range of salinity and sulfate concentrations, the cyanobacterial community is remarkably stable. C1 [Green, Stefan J.; Blackford, Cameron; Jahnke, Linda L.; Prufert-Bebout, Lee] NASA, Ames Res Ctr, Exobiol Branch, Moffett Field, CA 94035 USA. [Green, Stefan J.] SETI Inst, Mountain View, CA USA. [Bucki, Patricia] Agr Res Org, Volcani Ctr, IL-50250 Bet Dagan, Israel. RP Prufert-Bebout, L (reprint author), NASA, Ames Res Ctr, Exobiol Branch, MS 239-4, Moffett Field, CA 94035 USA. EM Leslie.E.Bebout@nasa.gov RI Green, Stefan/C-8980-2011; OI Green, Stefan/0000-0003-2781-359X NR 63 TC 28 Z9 29 U1 0 U2 9 PU NATURE PUBLISHING GROUP PI NEW YORK PA 75 VARICK STREET, 9TH FLOOR, NEW YORK, NY 10013-1917 USA SN 1751-7362 J9 ISME J JI ISME J. PD MAY PY 2008 VL 2 IS 5 BP 457 EP 470 DI 10.1038/ismej.2008.6 PG 14 WC Ecology; Microbiology SC Environmental Sciences & Ecology; Microbiology GA 302NG UT WOS:000255974500002 PM 18288215 ER PT J AU Osman, S La Duc, MT Dekas, A Newcombe, D Venkateswaran, K AF Osman, Shariff La Duc, Myron T. Dekas, Anne Newcombe, David Venkateswaran, Kasthuri TI Microbial burden and diversity of commercial airline cabin air during short and long durations of travel SO ISME JOURNAL LA English DT Article DE airline; cabin air; rapid detection; 16S rDNA; bioburden; diversity ID INTERCONTINENTAL FLIGHTS; AIRCRAFT; POPULATIONS; SYMPTOMS; ENVIRONMENTS; TUBERCULOSIS; SPACECRAFT; QUALITY; UNIFRAC; NASAL AB Total microbial burden and diversity associated with commercial airliner cabin air was assessed by molecular methods in 125 air samples from the business-class sections of 16 domestic and international flights. Viable microbial burden within these cabin air parcels constituted only 1-10% of the total microbial population and ranged from below detection limits to 1.2 x 10(4) cells m(-3) as determined with a validated ATP-based technology. Cultivable bacterial diversity was almost entirely limited to Gram-positive bacteria such as Staphylococcus and Bacillus. In contrast, cloning and sequencing 16S rRNA gene directly from the samples without cultivation indicated a significantly broader diversity, as sequences representing more than 100 species, and encompassing 12 classes of bacteria, were retrieved in varying abundance. Sequences of proteobacterial and Gram-positive lineage were retrieved most frequently (58% and 31% of all clone sequences, respectively), with Gram-positive and gamma-proteobacterial sequences dominating international flight samples and beta- and gamma-proteobacterial sequences comprising the largest portion of those retrieved from domestic flights. Significant differences in bacterial load and diversity were noted between samples obtained on domestic and international flights. The disparities observed in microbial abundance and diversity further underscore the immense value of state-of-the art molecular assays in augmenting traditional culture-based techniques. C1 [Venkateswaran, Kasthuri] CALTECH, Jet Prop Lab, Biotechnol & Planetary Protect Grp, Pasadena, CA 91109 USA. RP Venkateswaran, K (reprint author), CALTECH, Jet Prop Lab, Biotechnol & Planetary Protect Grp, M-S 89,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM kjvenkat@jpl.nasa.gov NR 48 TC 23 Z9 24 U1 4 U2 7 PU NATURE PUBLISHING GROUP PI NEW YORK PA 75 VARICK STREET, 9TH FLOOR, NEW YORK, NY 10013-1917 USA SN 1751-7362 J9 ISME J JI ISME J. PD MAY PY 2008 VL 2 IS 5 BP 482 EP 497 DI 10.1038/ismej.2008.11 PG 16 WC Ecology; Microbiology SC Environmental Sciences & Ecology; Microbiology GA 302NG UT WOS:000255974500004 PM 18256704 ER PT J AU Qi, C Chen, DR Greenberg, P AF Qi, Chaolong Chen, Da-Ren Greenberg, Paul TI Performance study of a unipolar aerosol mini-charger for a personal nanoparticle sizer SO JOURNAL OF AEROSOL SCIENCE LA English DT Article DE unipolar aerosol mini-charger; corona discharge; nanoparticles ID ULTRAFINE PARTICLES; RANGE AB We designed and constructed a corona-discharge-based unipolar mini-charger and experimentally evaluated its performance. The simple design and compact size make the prototype mini-charger well suited for use with portable aerosol sizing instruments based on particle electrical mobility techniques. In this work, we optimized the extrinsic charging efficiency of the prototype mini-charger for two different aerosol flow rates (i.e., 0.3 and 1.51pm). The optimal settings for the prototype operation are: (i) a corona current of 1 mu A and an ion driving voltage of 40V for the 0.31pm flow rate, and (ii) 2 mu A and 120V for the 1.51pm flowrate. Both intrinsic and extrinsic charging efficiencies of the prototype mini-charger at the optimal operational conditions were then evaluated for particles in diameters ranging from 10 to 200 nm. The intrinsic charging efficiency of the prototype reaches 100% at 20 nm for the 0.31pm flow rate, and 45 nm for the 1.51pm flow rate. The higher intrinsic charging efficiency at the low flowrate is due to the longer residence time of particles in the device. The extrinsic charging efficiency, however, is higher for the 1.51pm flow rate than for the 0.31pm flow rate due to charged particle loss in the prototype. Charge distributions of test monodisperse particles of different sizes were also measured by the Tandem-DMA technique. (C) 2008 Elsevier Ltd. All rights reserved. C1 [Qi, Chaolong; Chen, Da-Ren] Washington Univ, Dept Energy Environm & Chem Engn, St Louis, MO 63130 USA. [Greenberg, Paul] NASA, Glenn Res Ctr, Micrograv Combust & Reacting Syst Branch, Cleveland, OH 44135 USA. RP Chen, DR (reprint author), Washington Univ, Dept Energy Environm & Chem Engn, Campus Box 1180,1 Brookings Dr, St Louis, MO 63130 USA. EM chen@me.wustl.edu NR 19 TC 26 Z9 26 U1 0 U2 11 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0021-8502 J9 J AEROSOL SCI JI J. Aerosol. Sci. PD MAY PY 2008 VL 39 IS 5 BP 450 EP 459 DI 10.1016/j.jaerosci.2008.01.003 PG 10 WC Engineering, Chemical; Engineering, Mechanical; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 304LT UT WOS:000256111700007 ER PT J AU Sclafani, AJ Vassberg, JC Harrison, NA Rumsey, CL Rivers, SM Morrison, JH AF Sclafani, Anthony J. Vassberg, John C. Harrison, Neal A. Rumsey, Christopher L. Rivers, S. Melissa Morrison, Joseph H. TI CFL3D/OVERFLOW results for DLR-F6 wing/body and drag prediction workshop wing SO JOURNAL OF AIRCRAFT LA English DT Article; Proceedings Paper CT AIAA 45th Aerospace Sciences Meeting and Exhibit CY JAN 08-11, 2007 CL Reno, NV SP Amer Inst Aeronaut & Astronaut (AIAA) AB A series of overset grids was generated in response to the Third AIAA CFD Drag Prediction Workshop (DPW-III) which preceded the 25th Applied Aerodynamics Conference in June 2006. DPW-III focused on accurate drag prediction for wing/body and wing-alone configurations. The grid series built for each configuration consists of a coarse, medium, fine, and extra-fine mesh. The medium mesh is first constructed using the current state of best practices for overset grid generation. The medium mesh is then coarsened and enhanced by applying a factor of 1.5 to each (I, J, K) dimension. The resulting set of parametrically equivalent grids increase in size by a factor of roughly 3.5 from one level to the next denser level. Computational fluid dynamics simulations were performed on the overset grids using two different Reynolds-averaged Navier-Stokes flow solvers: CFL3D and OVERFLOW. The results were postprocessed using Richardson extrapolation to approximate grid-converged values of lift, drag, pitching moment, and angle of attack at the design condition. This technique appears to work well if the solution does not contain large regions of separated flow (similar to that seen in the DLR-F6 results) and appropriate grid densities are selected. The extra-fine grid data helped to establish asymptotic grid convergence for both the OVERFLOW FX2B wing/body results and the OVERFLOW DPW-W1/W2 wing-alone results. More CFL3D data are needed to establish grid convergence trends. The medium grid was used beyond the grid convergence study by running each configuration at several angles of attack so drag polars and lift/pitching moment curves could he evaluated. The alpha sweep results are used to compare data across configurations as well as across flow solvers. With the exception of the wing/body drag polar, the two codes compare well qualitatively showing consistent incremental trends and similar wing pressure comparisons. C1 Boeing Co, Phantom Works, Huntington Beach, CA 92647 USA. Boeing Co, Phantom Works, Huntington Beach, CA 92647 USA. NASA, Langley Res Ctr, Comp Aerosci Branch, Hampton, VA 23681 USA. NASA, Langley Res Ctr, Configurat Aerodynam Branch, Hampton, VA 23681 USA. Boeing Co, Phantom Works, Huntington Beach, CA 92647 USA. RP Sclafani, AJ (reprint author), Boeing Co, Phantom Works, Huntington Beach, CA 92647 USA. NR 22 TC 5 Z9 5 U1 1 U2 3 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0021-8669 J9 J AIRCRAFT JI J. Aircr. PD MAY-JUN PY 2008 VL 45 IS 3 BP 762 EP 780 DI 10.2514/1.30571 PG 19 WC Engineering, Aerospace SC Engineering GA 312RN UT WOS:000256688600004 ER PT J AU Vassberg, JC Tinoco, EN Mani, M Brodersen, OP Eisfeld, B Wahls, RA Morrison, JH Zickuhr, T Laflin, KR Mavriplis, DJ AF Vassberg, John C. Tinoco, Edward N. Mani, Mori Brodersen, Olaf P. Eisfeld, Bernhard Wahls, Richard A. Morrison, Joseph H. Zickuhr, Tom Laflin, Kelly R. Mavriplis, Dimitri J. TI Abridged summary of the third AIAA computational fluid dynamics drag prediction workshop SO JOURNAL OF AIRCRAFT LA English DT Article; Proceedings Paper CT AIAA 45th Aerospace Sciences Meeting and Exhibit CY JAN 08-11, 2007 CL Reno, NV SP Amer Inst Aeronaut & Astronaut AB Results from the Third AIAA Drag Prediction Workshop (DPW-III) are summarized. The workshop focused on the prediction of both absolute and differential drag levels for wing-body and wing-alone configurations that are representative of transonic transport aircraft. The baseline DLR-F6 wing-body geometry, previously used in DPW-II, is also augmented with a side-of-body fairing to help reduce the complexity of the flow physics in the wing-body juncture region. In addition, two new wing-alone geometries have been developed for DPW-III. Numerical calculations are performed using industry-relevant test cases that include lift-specific and fixed-alpha flight conditions, as well as full drag polars. Drag, lift, and pitching-moment predictions from numerous Reynolds-averaged Navier-Stokes computational fluid dynamics methods are presented, focused on fully turbulent flows. Solutions are performed on structured, unstructured, and hybrid grid systems. The structured grid sets include point-matched multiblock meshes and overset grid systems. The unstructured and hybrid grid sets are composed of tetrahedral, pyramid, and prismatic elements. Effort was made to provide a high-quality and parametrically consistent family of grids for each grid type about each configuration under study. The wing-body families are composed of a coarse, medium, and fine grid, whereas the wing-alone families also include an extra-fine mesh. These mesh sequences are used to help determine how the provided flow solutions fare with respect to asymptotic grid convergence, and are used to estimate an absolute drag for each configuration. C1 Boeing Co, Chicago, IL 60606 USA. DLR Inst Aerodynam & Flow Technol, D-38108 Braunschweig, Germany. NASA, Langley Res Ctr, Configurat Aerodynam Branch, Hampton, VA 23681 USA. Cessna Aircraft Co, Wichita, KS 67218 USA. Univ Wyoming, Laramie, WY 82071 USA. RP Vassberg, JC (reprint author), Boeing Co, Chicago, IL 60606 USA. NR 43 TC 19 Z9 23 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0021-8669 J9 J AIRCRAFT JI J. Aircr. PD MAY-JUN PY 2008 VL 45 IS 3 BP 781 EP 798 DI 10.2514/1.30572 PG 18 WC Engineering, Aerospace SC Engineering GA 312RN UT WOS:000256688600005 ER PT J AU Edwards, JW Wieseman, CD AF Edwards, John W. Wieseman, Carol D. TI Flutter and divergence analysis using the generalized aeroelastic analysis method SO JOURNAL OF AIRCRAFT LA English DT Article; Proceedings Paper CT AIAA/ASME/ASCE/AHS/ASC 44th Structures, Structural Dynamics and Materials Conference CY APR 07-10, 2003 CL Norfolk, VA SP AIAA, ASME, ASCE, AHS, ASC ID ARBITRARY MOTIONS; EQUATION; MODELS AB The generalized aeroelastic analysis method is applied to the analysis of three well-studied check cases: restrained and unrestrained airfoil models and a wing model. An eigenvalue iteration procedure is used for converging upon roots of the complex stability matrix. For the airfoil models, exact root loci are given, which clearly illustrate the nature of the flutter and divergence instabilities. The singularities involved are enumerated, including an additional pole at the origin for the unrestrained airfoil case and the emergence of an additional pole on the positive real axis at the divergence speed for the restrained airfoil case. Inconsistencies and differences among published aeroelastic root loci and the new, exact results are discussed and resolved. The generalization of a doublet lattice method computer code is described, and the code is applied to the calculation of root loci for the wing model for incompressible and for subsonic flow conditions. The error introduced in the reduction of the singular integral equation underlying the unsteady lifting surface theory to a linear algebraic equation is discussed. Acknowledging this inherent error, the solutions of the algebraic equation by generalized aeroelastic analysis method are termed "exact." The singularities of the problem are discussed, and exponential series approximations used in the evaluation of the kernel function are shown to introduce a dense collection of poles and zeroes on the negative real axis. Again, inconsistencies and differences among published aeroelastic root loci and the new, "exact" results are discussed and resolved. In all cases, aeroelastic flutter and divergence speeds and frequencies are in good agreement with published results. The generalized aeroelastic analysis method solution procedure allows complete control over Mach number, velocity, density, and complex frequency. Thus, all points on the computed root loci can be matched-point, consistent solutions without recourse to complex mode tracking logic or dataset interpolation, as in the k, p-k, and g-solution methods. C1 [Edwards, John W.; Wieseman, Carol D.] NASA, Langley Res Ctr, Aeroelastic Branch, Hampton, VA 23681 USA. RP Edwards, JW (reprint author), NASA, Langley Res Ctr, Aeroelastic Branch, Hampton, VA 23681 USA. NR 34 TC 14 Z9 16 U1 0 U2 5 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0021-8669 J9 J AIRCRAFT JI J. Aircr. PD MAY-JUN PY 2008 VL 45 IS 3 BP 906 EP 915 DI 10.2514/1.30078 PG 10 WC Engineering, Aerospace SC Engineering GA 312RN UT WOS:000256688600014 ER PT J AU Lan, CE Bianchi, S Brandon, JM AF Lan, C. Edward Bianchi, Silvia Brandon, Jay M. TI Estimation of nonlinear aerodynamic roll models for identification of uncommanded rolling motions SO JOURNAL OF AIRCRAFT LA English DT Article; Proceedings Paper CT AIAA Atmospheric Flight Mechanics Conference CY AUG 21-24, 2006 CL Keystone, CO SP AIAA ID ABRUPT WING STALL; ROCK; F/A-18E AB Detailed analysis of wind-tunnel data in free-to-roll testing of one aircraft model, the preproduction F/A-18E, in a transonic tunnel is presented. The main purpose is to identify possible uncommanded rolling motions of the full-scale aircraft by examining the roll dynamic characteristics of the model in the tunnel. To improve the tunnel balance data, the bearing-friction effect on the balance rolling-moment coefficient was removed. The corrected rolling-moment coefficients are then modeled through a fuzzy-logic algorithm. The resulting aerodynamic models are employed in calculating all roll derivatives by a central-difference scheme. The proposed wing-drop theory relies on the values of the relative aerodynamic stiffness in the rolling equation of motion, which is assumed to be composed of two terms: derivatives with respect to the roll angle alone and second-order derivatives of the rolling-moment coefficient with respect to the roll angle and angle of attack. Wing drop is predicted if the relative aerodynamic stiffness changes sign from that of the overall motion and if the contributions to the rolling-moment coefficient from both the first-order and second-order derivatives are of the same sign and are small in value. This is equivalent to the vanishing of a frequency with damping in the vibration theory. It is found that at a low angle of attack and a transonic Mach number, the dynamic motion is wing rock. As the angle of attack is increased, the wing-drop condition is initially exhibited with a single event, then with multiple occurrences of wing drop at a higher angle of attack, with the magnitude of roll-off angles changing with time. It is also found that wing-rock motion in the tunnel on a free-to-roll test rig is mostly caused by the unstable effect of time rate of sideslip angle, not by the traditional roll damping due to roll rate. C1 [Lan, C. Edward; Bianchi, Silvia] Univ Kansas, Dept Aerosp Engn, Lawrence, KS 66045 USA. [Brandon, Jay M.] NASA, Langley Res Ctr, Flight Dynam Branch, Hampton, VA 23681 USA. RP Lan, CE (reprint author), Univ Kansas, Dept Aerosp Engn, Lawrence, KS 66045 USA. NR 20 TC 9 Z9 9 U1 1 U2 3 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0021-8669 J9 J AIRCRAFT JI J. Aircr. PD MAY-JUN PY 2008 VL 45 IS 3 BP 916 EP 922 DI 10.2514/1.30388 PG 7 WC Engineering, Aerospace SC Engineering GA 312RN UT WOS:000256688600015 ER PT J AU Lim, JW Strawn, RC AF Lim, Joon W. Strawn, Roger C. TI Computational modeling of HART II blade-vortex interaction loading and wake system SO JOURNAL OF AIRCRAFT LA English DT Article; Proceedings Paper CT AIAA 45th Aerospace Sciences Meeting and Exhibit CY JAN 08-11, 2007 CL Reno, NV SP Amer Inst Aeronaut & Astronaut ID INTERACTION AIRLOADS; PREDICTION AB Correlations using a loosely coupled trim methodology of the computational fluid dynamics (OVERFLOW-2) and computational structural dynamics (CAMRAD-II) codes are presented to calculate the helicopter rotor blade-vortex interaction airloads and wake system for the higher-harmonic aeroacoustic rotor test (HART 11) rotor at an advance ratio of 0.15. Five different grid models are studied to quantify the effects of 1 rid refinement on rotor-wake resolution. The fine grid model has a total of 113 million grid points and it improves airload predictions compared with the standard grid model for three HART 11 test cases: baseline, minimum noise, and minimum vibration. The rotor-wake positions are well predicted by this fine grid model. The computed vorticity field for a young vortex using the fine grid model is compared with the measured particle image velocimetry data and the results are good. The fine grid model underpredicts the experimental value for the maximum vorticity by 61%. The predicted vortex core radius is 15% in chord for the fine grid while the measured data show about 5% chord length. The predicted swirl velocity is, however, higher than the measured data for this vortex. The results in this paper provide the first quantitative comparisons between the measured and computational fluid dynamics/computational structural dynamics computed flowfield for a helicopter rotor-wake system. C1 [Lim, Joon W.; Strawn, Roger C.] USA, Ames Res Ctr, Aeroflightdynam Directorate AMRDEC, Moffett Field, CA USA. RP Lim, JW (reprint author), USA, Ames Res Ctr, Aeroflightdynam Directorate AMRDEC, M-S 215-1, Moffett Field, CA USA. NR 24 TC 9 Z9 9 U1 0 U2 1 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0021-8669 J9 J AIRCRAFT JI J. Aircr. PD MAY-JUN PY 2008 VL 45 IS 3 BP 923 EP 933 DI 10.2514/1.31081 PG 11 WC Engineering, Aerospace SC Engineering GA 312RN UT WOS:000256688600016 ER PT J AU Albertani, R Stanford, B DeLoach, R Hubner, JP Ifju, P AF Albertani, R. Stanford, B. DeLoach, R. Hubner, J. P. Ifju, P. TI Wind-tunnel testing and modeling of a micro air vehicle with flexible wings SO JOURNAL OF AIRCRAFT LA English DT Article ID AERODYNAMICS; DEFORMATION AB The field of micro air vehicles is relatively immature; consequently, high-fidelity simulations do not yet exist for a generic aircraft. The fidelity of flight dynamic simulations is closely correlated to the reliability of models representing the vehicle's aerodynamic and propulsion characteristics in the entire flight envelope, including the nonlinear region. This paper discusses wind-tunnel experiments performed to investigate the aerodynamic and mechanical characteristics of micro air vehicles with flexible wings in different conditions of propeller type, motor power, and elevator deflections. Visual image correlation was used to measure the deformation of the flexible wings to quantify general features such as variations in aerodynamic and geometric twist angle. Aerodynamic and propulsion results were used to formulate empirical models of the relevant coefficients in the form of multiple linear regressions and to estimate the effectors' functional dependencies and interactions. High-order nonlinear interactions were confirmed between the coefficients of lift, drag, and pitching moment with the independent variables. The rates of the dependencies with elevator deflections and angle of attack were found, to some extent, to be motor voltage and dynamic pressure dependent, evincing a strong coupling with the propeller speed. C1 [Albertani, R.; Stanford, B.; Ifju, P.] Univ Florida, Gainesville, FL 32611 USA. [DeLoach, R.] NASA, Langley Res Ctr, Hampton, VA 23681 USA. [Hubner, J. P.] Univ Alabama, Tuscaloosa, AL 35487 USA. RP Albertani, R (reprint author), Res & Engn Educ Facil, Shalimar, FL 32579 USA. NR 16 TC 7 Z9 7 U1 0 U2 6 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0021-8669 J9 J AIRCRAFT JI J. Aircr. PD MAY-JUN PY 2008 VL 45 IS 3 BP 1025 EP 1032 DI 10.2514/1.33338 PG 8 WC Engineering, Aerospace SC Engineering GA 312RN UT WOS:000256688600026 ER PT J AU Radek, KA Baer, LA Eckhardt, J DiPietro, LA Wade, CE AF Radek, Katherine A. Baer, Lisa A. Eckhardt, Jennifer DiPietro, Luisa A. Wade, Charles E. TI Mechanical unloading impairs keratinocyte migration and angiogenesis during cutaneous wound healing SO JOURNAL OF APPLIED PHYSIOLOGY LA English DT Article DE tissue repair; rat; skin ID ENDOTHELIAL GROWTH-FACTOR; BED REST; SIMULATED MICROGRAVITY; MAMMALIAN-CELLS; RESPONSES; RAT; INACTIVITY; LIGAMENT; REPAIR; TISSUE AB Although initially thought to improve an individual's ability to heal, mechanical unloading promoted by extended periods of bed rest has emerged as a contributing factor to delayed or aberrant tissue repair. Using a rat hindlimb unloading (HLU) model of hypogravity, we mimicked some aspects of physical inactivity by removing weight-bearing loads from the hindlimbs and producing a systemic cephalic fluid shift. This model simulates bed rest in that the animal undergoes physiological adaptations, resulting in a reduction in exercise capability, increased frequency of orthostatic intolerance, and a reduction in plasma volume. To investigate whether changes associated with prior prolonged bed rest correlate with impaired cutaneous wound healing, we examined wound closure, angiogenesis, and collagen content in day 2 to day 21 wounds from rats exposed to HLU 2 wk before excisional wounding. Wound closure was delayed in day 2 wounds from HLU rats compared with ambulatory controls. Although the levels of proangiogenic growth factors, fibroblast growth factor-2 (FGF-2), and vascular endothelial growth factor (VEGF) were similar between the two groups, wound vascularity was significantly reduced in day 7 wounds from HLU animals. To further examine this disparity, total collagen content was assessed but found to be similar between the two groups. Taken together, these results suggest that keratinocyte and endothelial cell function may be impaired during the wound healing process under periods of prolonged inactivity or bed rest. C1 [Baer, Lisa A.; Wade, Charles E.] USA, Inst Surg Res, Ft Sam Houston, TX 78234 USA. [Radek, Katherine A.] Univ Calif San Diego, Dept Med, San Diego, CA 92103 USA. [Radek, Katherine A.; Baer, Lisa A.; Eckhardt, Jennifer; Wade, Charles E.] NASA, Ames Res Ctr, Div Life Sci, Moffett Field, CA 94035 USA. [DiPietro, Luisa A.] Univ Illinois, Coll Dent, Ctr Wound Healing & Tissue Regenerat, Chicago, IL USA. RP Wade, CE (reprint author), USA, Inst Surg Res, 3400 Rawley E Chambers Ave, Ft Sam Houston, TX 78234 USA. EM charles.wade@amedd.army.mil NR 63 TC 11 Z9 12 U1 0 U2 3 PU AMER PHYSIOLOGICAL SOC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 8750-7587 J9 J APPL PHYSIOL JI J. Appl. Physiol. PD MAY PY 2008 VL 104 IS 5 BP 1295 EP 1303 DI 10.1152/japplphysiol.00977.2007 PG 9 WC Physiology; Sport Sciences SC Physiology; Sport Sciences GA 295VB UT WOS:000255500900010 PM 18292299 ER PT J AU Campbell, JR Sassen, K Welton, EJ AF Campbell, James R. Sassen, Kenneth Welton, Ellsworth J. TI Elevated cloud and aerosol layer retrievals from Micropulse Lidar Signal Profiles SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID ENTRAINMENT ZONE THICKNESS; BOUNDARY-LAYER; BACKSCATTER PROFILES; RADIATION; MISSION; HEIGHT; TOP AB A threshold-based detection algorithm for cloud and aerosol layer heights in elevated micropulse lidar data (0.523 mu m) is described. Thresholds for differentiating cloud and aerosol signals from that of the molecular atmosphere are based on the signal uncertainties of the level 1.0 Micropulse Lidar Network (MPLNET) data product. To illustrate the algorithm, data from 1 to 10 June 2003 collected by an MPLNET instrument at the South Pole are discussed for polar stratospheric cloud-height retrievals. Additional tests are run for algorithm sensitivity relative to variable solar background scenes. The algorithm is run at multiple temporal resolutions. Results derived at a base resolution are used to screen attenuation-limited profiles from longer time averages to improve performance. A signal normalization step using a theoretical molecular scattering profile limits the application of the technique in the lower atmosphere for a ground-based instrument. This would not be the case for some nadir-viewing lidars, and the application of the algorithm to airborne and satellite datasets is speculated. C1 [Campbell, James R.; Sassen, Kenneth] Univ Alaska Fairbanks, Inst Geophys, Atmospher Sci Program, Fairbanks, AK 99775 USA. [Welton, Ellsworth J.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Campbell, JR (reprint author), Sci Syst & Applicat Inc, 10210 Greenbelt Rd,Suite 600, Lanham, MD 20706 USA. EM James_Campbell@ssaihq.com RI Welton, Ellsworth/A-8362-2012; Campbell, James/C-4884-2012 OI Campbell, James/0000-0003-0251-4550 NR 30 TC 30 Z9 30 U1 5 U2 20 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0739-0572 J9 J ATMOS OCEAN TECH JI J. Atmos. Ocean. Technol. PD MAY PY 2008 VL 25 IS 5 BP 685 EP 700 DI 10.1175/2007JTECHA1034.1 PG 16 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA 303VM UT WOS:000256069000004 ER PT J AU Ottaviani, M Stamnes, K Koskulics, J Eide, H Long, SR Su, W Wiscombe, W AF Ottaviani, Matteo Stamnes, Knut Koskulics, Jeff Eide, Hans Long, Steven R. Su, Wenying Wiscombe, Warren TI Light reflection from water waves: Suitable setup for a polarimetric investigation under controlled laboratory conditions SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID OF-AMPLITUDE PHOTOPOLARIMETER; EMPIRICAL MODE DECOMPOSITION; HILBERT SPECTRUM; BEAM-SPLITTERS; CALIBRATION AB The reflection of sunlight from a wavy water surface, often referred to as sun glint, is a well-known phenomenon that presents challenges but also hitherto untapped opportunities in remote sensing based on satellite imagery. Despite being extensively investigated in the open ocean, sun glint lacks a fundamental characterization obtained under controlled laboratory conditions. A novel apparatus is presented, which is suitable for highly time-resolved measurements of light reflection from different computer-controlled wave states, with special emphasis on the detection of the polarization components. Such a system can help establish a link between the evanescent "atomic glints" from a single wave facet and the familiar sunglint pattern obtained by time averaging over a surface area containing many facets. C1 [Ottaviani, Matteo; Stamnes, Knut; Koskulics, Jeff] Stevens Inst Technol, Light & Life Lab, Dept Phys & Engn Phys, Hoboken, NJ 07030 USA. [Eide, Hans] Univ Oslo, USIT, Oslo, Norway. [Long, Steven R.] NASA, Goddard Space Flight Ctr, Wallops Isl, VA USA. [Su, Wenying] Sci Syst & Applicat Inc, Hampton, VA USA. RP Ottaviani, M (reprint author), Stevens Inst Technol, Light & Life Lab, Dept Phys & Engn Phys, Hoboken, NJ 07030 USA. EM mottavia@stevens.edu RI Wiscombe, Warren/D-4665-2012 OI Wiscombe, Warren/0000-0001-6844-9849 NR 23 TC 6 Z9 6 U1 1 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0739-0572 EI 1520-0426 J9 J ATMOS OCEAN TECH JI J. Atmos. Ocean. Technol. PD MAY PY 2008 VL 25 IS 5 BP 715 EP 728 DI 10.1175/2007JTECHA1049.1 PG 14 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA 303VM UT WOS:000256069000006 ER PT J AU Cazes-Boezio, G Menemenlis, D Mechoso, CR AF Cazes-Boezio, Gabriel Menemenlis, Dimitris Mechoso, Carlos R. TI Impact of ECCO ocean-state estimates on the initialization of seasonal climate forecasts SO JOURNAL OF CLIMATE LA English DT Article ID GENERAL-CIRCULATION MODEL; DATA ASSIMILATION SYSTEM; COUPLED MODEL; TROPICAL PACIFIC; ENSO PREDICTION; BOUNDARY; ENSEMBLE; ADJOINT; VARIABILITY; CYCLE AB The impact of ocean-state estimates generated by the consortium for Estimating the Circulation and Climate of the Ocean (ECCO) on the initialization of a coupled general circulation model (CGCM) for seasonal climate forecasts is examined. The CGCM consists of the University of California, Los Angeles, Atmospheric GCM (UCLA AGCM) and an ECCO ocean configuration of the Massachusetts Institute of Technology GCM (MITgcm). The forecasts correspond to ensemble seasonal hindcasts for the period 1993-2001. For the forecasts, the ocean component of the CGCM is initialized in either early March or in early June using ocean states provided either by an unconstrained forward ocean integration of the MITgcm (the "baseline" hindcasts) or by data-constrained ECCO results (the "ECCO" hindcasts). Forecast skill for both the baseline and the ECCO hindcasts is significantly higher than persistence and compares well with the skill of other state-of-the art CGCM forecast systems. For March initial conditions, the standard errors of sea surface temperature (SST) anomalies in ECCO hindcasts (relative to observed anomalies) are up to 1 C smaller than in the baseline hindcasts over the central and eastern equatorial Pacific (150 degrees-120 degrees W). For June initial conditions, the errors of ECCO hindcasts are up to 0.5 degrees C smaller than in the baseline hindcasts. The smaller standard error of the ECCO hindcasts is, in part, due to a more realistic equatorial thermocline structure of the ECCO initial conditions. This study confirms the value of physically consistent ocean-state estimation for the initialization of seasonal climate forecasts. C1 [Cazes-Boezio, Gabriel] Univ Uruguay, Sch Engn, IMFIA, Inst Fluid Mechan & Environm Engn, Montevideo 11300, Uruguay. [Cazes-Boezio, Gabriel; Mechoso, Carlos R.] Univ Calif Los Angeles, Dept Atmospher & Ocean Sci, Los Angeles, CA USA. [Menemenlis, Dimitris] CALTECH, Jet Propuls Lab, Pasadena, CA 91125 USA. RP Cazes-Boezio, G (reprint author), Univ Uruguay, Sch Engn, IMFIA, Inst Fluid Mechan & Environm Engn, Julio Herrera & Reissig 565, Montevideo 11300, Uruguay. EM agcm@fing.edu.uy NR 56 TC 13 Z9 14 U1 0 U2 5 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 EI 1520-0442 J9 J CLIMATE JI J. Clim. PD MAY PY 2008 VL 21 IS 9 BP 1929 EP 1947 DI 10.1175/007JCLI1574.1 PG 19 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 294LT UT WOS:000255408200007 ER PT J AU Chang, CH Liou, MS AF Chang, Chih-Hao Liou, Meng-Sing TI A robust and accurate approach to computing compressible multiphase flow: Stratified flow model and AUSM(+)-up scheme (vol 225, pg 840, 2007) SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Correction C1 [Chang, Chih-Hao] Univ Calif Santa Barbara, Ctr Risk Studies & Safety, Goleta, CA 93117 USA. [Liou, Meng-Sing] NASA, Glenn Res Ctr, Aeropropul Div, Cleveland, OH 44135 USA. RP Chang, CH (reprint author), Univ Calif Santa Barbara, Ctr Risk Studies & Safety, 6740 Cortona Dr, Goleta, CA 93117 USA. EM chchang@engineering.ucsb.edu; meng-sing.liou@grc.nasa.gov NR 1 TC 0 Z9 0 U1 2 U2 9 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD MAY 1 PY 2008 VL 227 IS 10 BP 5360 EP 5360 DI 10.1016/j.jcp.2008.01.041 PG 1 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 295AI UT WOS:000255447000028 ER PT J AU Paletz, SBF Peng, KP AF Paletz, Susannah B. F. Peng, Kaiping TI Implicit theories of creativity across cultures - Novelty and appropriateness in two product domains SO JOURNAL OF CROSS-CULTURAL PSYCHOLOGY LA English DT Article; Proceedings Paper CT 6th Annual Meeting of the Society-for-Personality-and-Social-Psychology CY 2005 CL New Orleans, LA SP Soc Personal & Social Psychol DE implicit theories; creativity; culture; novelty; appropriateness ID HONG-KONG; COGNITION; CHINESE; INTELLIGENCE; PERSONALITY; PSYCHOLOGY; PERCEPTION; WEST; EAST AB One potential problem for creativity theory is whether both novelty and appropriateness are equally valid dimensions across cultures. Taking an implicit theory approach, the authors surveyed more than 400 students from Japan, China, and the United States. Using repeated measures scenarios of cooking and textbook products, novelty was found to be important across the three countries for evaluations of creativity. However, the Chinese were more swayed than were the Americans by the novelty manipulation in terms of how much they desired the products. Appropriateness was more important for Americans and Japanese for evaluations of creativity and desire for products. Both novelty and appropriateness had large effects. Rather than relying on assumed country variations, the authors argue that cross-cultural research be used to understand the nature of creativity. C1 [Paletz, Susannah B. F.; Peng, Kaiping] Univ Calif Berkeley, Berkeley, CA 94720 USA. RP Paletz, SBF (reprint author), NASA, Ames Res Ctr, Mail Stop 262-4, Moffett Field, CA 94035 USA. EM sbfpaletz@gmail.com NR 52 TC 34 Z9 34 U1 2 U2 12 PU SAGE PUBLICATIONS INC PI THOUSAND OAKS PA 2455 TELLER RD, THOUSAND OAKS, CA 91320 USA SN 0022-0221 EI 1552-5422 J9 J CROSS CULT PSYCHOL JI J. Cross-Cult. Psychol. PD MAY PY 2008 VL 39 IS 3 BP 286 EP 302 DI 10.1177/0022022108315112 PG 17 WC Psychology, Social SC Psychology GA 292TR UT WOS:000255289500004 ER PT J AU Speer, KM Neudeck, PG Spry, DJ Trunek, AJ Pirouz, P AF Speer, Kevin M. Neudeck, Philip G. Spry, David J. Trunek, Andrew J. Pirouz, Pirouz TI Cross-sectional TEM and KOH-etch studies of extended defects in 3C-SiC p(+)n junction diodes grown on 4H-SiC mesas SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article DE 3C-SiC; stacking fault; double positioning boundary; heteroepitaxy; transmission electron microscopy; defect-preferential etching ID SILICON-CARBIDE; DEVICES; BIAS AB This article presents cross-sectional transmission electron microscopy and molten-potassium hydroxide etching studies of (111) 3C-SiC diodes which we previously reported to be free of forward-voltage drift despite abundant electroluminescent linear features presumed to be defects. Our results show that the majority of linear features are stacking faults lying in inclined {111} planes. Additionally, high densities of isolated etch pits (10(6)-10(8) cm(-2)) are observed in 3C films grown on stepped 4H mesas, while 3C films nucleated on step-free 4H mesas exhibited orders of magnitude fewer etch pits and stacking faults. Defect formation mechanisms whose impetuses are steps on the 4H-SiC pregrowth mesa are discussed. C1 [Speer, Kevin M.] Case Western Reserve Univ, Dept Comp Sci & Elect Engn, Cleveland, OH 44106 USA. [Neudeck, Philip G.; Spry, David J.; Trunek, Andrew J.] NASA, Glenn Res Ctr, Ohio Aerosp Inst, Cleveland, OH 44135 USA. [Pirouz, Pirouz] Case Western Reserve Univ, Dept Mat Sci & Engn, Cleveland, OH 44106 USA. RP Speer, KM (reprint author), Case Western Reserve Univ, Dept Comp Sci & Elect Engn, Cleveland, OH 44106 USA. EM kevin.m.speer@ieee.org NR 22 TC 8 Z9 8 U1 0 U2 8 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD MAY PY 2008 VL 37 IS 5 BP 672 EP 680 DI 10.1007/s11664-007-0297-z PG 9 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA 289CU UT WOS:000255033400025 ER PT J AU Picard, YN Twigg, ME Caldwell, JD Eddy, CR Neudeck, PG Trunek, AJ Powell, JA AF Picard, Yoosuf N. Twigg, Mark E. Caldwell, Joshua D. Eddy, Charles R., Jr. Neudeck, Philip G. Trunek, Andrew J. Powell, J. Anthony TI Epitaxial SiC growth morphology and extended defects investigated by electron backscatter diffraction and electron channeling contrast imaging SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article DE Electron channeling; backscatter diffraction; 4H-SiC; dislocations; extended defects; atomic steps; polytype ID MICROSCOPE; MESAS; SURFACES AB Electron backscatter diffraction (EBSD) and electron channeling contrast imaging (ECCI) were employed to investigate epitaxial SiC growth on 4H-SiC mesa structures. SiC polytypes were identified by indexing Kikuchi maps recorded from various points on the mesa surfaces. Orientation contrast was observed between different polytype surfaces using ECCI by forescattered electron detection. Extended defects in 3C-SiC were imaged directly by ECCI. Additionally, the ECCI technique was utilized to correlate dislocations with atomic step morphologies for various mesa surfaces. Evidence of vertical growth enhancement in the form of additional faceting was attributed to the presence of threading screw dislocations at mesa surfaces. Atomic steps were observed very near the edges of some mesa surfaces free of dislocations. C1 [Picard, Yoosuf N.; Twigg, Mark E.; Caldwell, Joshua D.; Eddy, Charles R., Jr.] USN, Res Lab, Div Elect Sci & Technol, Washington, DC 20375 USA. [Neudeck, Philip G.] NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. [Trunek, Andrew J.] OAI, Cleveland, OH 44135 USA. [Powell, J. Anthony] Sest Inc, Cleveland, OH 44135 USA. RP Picard, YN (reprint author), USN, Res Lab, Div Elect Sci & Technol, Washington, DC 20375 USA. EM yoosuf.picard@nrl.navy.mil RI Caldwell, Joshua/B-3253-2008; OI Caldwell, Joshua/0000-0003-0374-2168; Picard, Yoosuf/0000-0002-2853-5213 NR 20 TC 10 Z9 10 U1 0 U2 5 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD MAY PY 2008 VL 37 IS 5 BP 691 EP 698 DI 10.1007/s11664-007-0308-0 PG 8 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA 289CU UT WOS:000255033400028 ER PT J AU Lee, JSF Berejikian, BA AF Lee, J. S. F. Berejikian, B. A. TI Effects of the rearing environment on average behaviour and behavioural variation in steelhead SO JOURNAL OF FISH BIOLOGY LA English DT Article DE conservation hatchery; environmental enrichment; exploratory behaviour ID JUVENILE STEELHEAD; REINTRODUCTION PROGRAMS; BRACHYRAPHIS-EPISCOPI; PREDATOR RECOGNITION; ONCORHYNCHUS-MYKISS; WILD POPULATIONS; HATCHERY TANKS; HABITAT USE; FISH; BOLDNESS AB In the context of conservation hatcheries that seek to bolster wild populations by releasing captively-reared fishes into the wild, steelhead Oncorhynchus mykiss were used to test the hypothesis that naturalistic rearing environments promote adaptive behaviour that might otherwise not develop in typical hatchery environments. When comparisons were made among fish reared in barren, structured or structurally variable environments (i.e. the location of the structure was repositioned every 2-3 days), structure in the rearing environment increased future exploratory behaviour, but only if the structure was stable. Under conditions of high perceived predation risk, the fish no longer exhibited increased exploratory behaviour, suggesting that it is expressed in an adaptive, context-dependant manner. Another concern with hatcheries is that relaxed selection over multiple generations in captivity can increase maladaptive behavioural variation. Compared to rearing in hatchery-typical barren environments, rearing in structured-stable environments decreased behavioural variation. This effect, which occurred during development and did not involve selection, demonstrates a different mechanism for change in behavioural variation in captivity. These experiments show that effects of structure and structural stability occur at the level of both average behaviour and behavioural variation, and suggest that these effects should be considered when fishes are reared in hatcheries for later release into the wild. C1 [Lee, J. S. F.; Berejikian, B. A.] Manchester Res Stn, Resource Enhancement & Utilizat Technol Div, NW Fisheries Sci Ctr, Natl Marine Fisheries Serv, Manchester, WA 98353 USA. RP Lee, JSF (reprint author), Manchester Res Stn, Resource Enhancement & Utilizat Technol Div, NW Fisheries Sci Ctr, Natl Marine Fisheries Serv, POB 130, Manchester, WA 98353 USA. EM jon.lee@noaa.gov NR 47 TC 23 Z9 23 U1 3 U2 26 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0022-1112 J9 J FISH BIOL JI J. Fish Biol. PD MAY PY 2008 VL 72 IS 7 BP 1736 EP 1749 DI 10.1111/j.1095-8649.2008.01848.x PG 14 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA 289FQ UT WOS:000255040800012 ER PT J AU Nguyen, N Krishnakumar, K Kaneshige, J Nespeca, P AF Nguyen, Nhan Krishnakumar, Kalmanje Kaneshige, John Nespeca, Pascal TI Flight dynamics and hybrid adaptive control of damaged aircraft SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS LA English DT Article; Proceedings Paper CT AIAA/AAS Astrodynamics Specialist Conference CY AUG 21-24, 2006 CL Keystone, CO SP AIAA, AAS ID SAFETY AB This paper presents a recent study to investigate flight dynamics and adaptive control methods for stability and control recovery of a damaged generic transport aircraft. Aerodynamic modeling of damage effects is performed using an aerodynamic code to assess changes in the stability and control derivatives of the damaged aircraft. Flight dynamics for a general aircraft are developed to account for changes in aerodynamics, mass properties, and the center of gravity that can compromise the stability of the damaged aircraft. An iterative trim analysis is developed to compute incremental trim states. A neural network hybrid direct-indirect adaptive flight control is developed for the stability augmentation control of the damaged aircraft. The proposed method performs an online estimation of damaged plant dynamics to improve the command tracking performance in conjunction with a direct adaptive controller. The plant estimation is based on two approaches: 1) an indirect adaptive law derived from the Lyapunov stability theory to ensure that the tracking error is bounded, and 2) a recursive least-squares method that minimizes the modeling error. Simulations show that the hybrid adaptive controller can provide a significant improvement in the tracking performance over a direct adaptive controller working alone. C1 [Nguyen, Nhan; Krishnakumar, Kalmanje; Kaneshige, John] NASA, Ames Res Ctr, Intelligent Syst Div, Moffett Field, CA 94035 USA. [Nespeca, Pascal] Univ Calif Davis, Mech Aerosp Engn Dept, Davis, CA 95616 USA. RP Nguyen, N (reprint author), NASA, Ames Res Ctr, Intelligent Syst Div, Mail Stop 269-1, Moffett Field, CA 94035 USA. NR 29 TC 40 Z9 45 U1 0 U2 5 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0731-5090 J9 J GUID CONTROL DYNAM JI J. Guid. Control Dyn. PD MAY-JUN PY 2008 VL 31 IS 3 BP 751 EP 764 DI 10.2514/1.28142 PG 14 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 298OY UT WOS:000255698200027 ER PT J AU Markley, FL AF Markley, F. L. TI Optimal attitude matrix from two vector measurements SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS LA English DT Article ID SATELLITE C1 NASA, Goddard Space Flight Ctr, Guidance Navigat & Control Syst Engn Branch, Greenbelt, MD 20771 USA. RP Markley, FL (reprint author), NASA, Goddard Space Flight Ctr, Guidance Navigat & Control Syst Engn Branch, Code 591, Greenbelt, MD 20771 USA. NR 21 TC 15 Z9 16 U1 0 U2 2 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0731-5090 J9 J GUID CONTROL DYNAM JI J. Guid. Control Dyn. PD MAY-JUN PY 2008 VL 31 IS 3 BP 765 EP 768 DI 10.2514/1.35597 PG 4 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 298OY UT WOS:000255698200028 ER PT J AU Kraft-Bermuth, S Arnaboldi, C Ferri, E Kilbourne, C Margesin, B McCammon, D Monfardini, A Nucciotti, A Pessina, G Previtali, E Schaeffer, D Sisti, M AF Kraft-Bermuth, S. Arnaboldi, C. Ferri, E. Kilbourne, C. Margesin, B. McCammon, D. Monfardini, A. Nucciotti, A. Pessina, G. Previtali, E. Schaeffer, D. Sisti, M. TI Development and characterization of microcalorimeters for a next generation Re-187 beta-decay experiment SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article DE neutrino mass; single beta-decay; microcalorimeters ID NEUTRINO MASS EXPERIMENT; ARRAYS AB It has been demonstrated in the past that observing the beta-decay spectrum of Re-187 with microbolometers provides a suitable method to determine the mass of the electron anti-neutrino from beta-endpoint measurements. In a first step, with the experiment MIBETA a sensitivity of m (nu e) <= 15 eV/c(2) was achieved. To compete with the sensitivity of m (nu e) <= 2.2 eV/c(2) established by the Mainz/Troitsk tritium beta-decay experiment and the limit of m (nu e) <= 0.2 eV/c(2) aimed at with KATRIN, a new experiment MARE has been initiated. As a first stage (MARE-1), 300 detectors consisting of silicon implanted thermistors, produced by NASA/GSFC, and absorbers of AgReO4 crystals will be mounted. To optimize the experimental setup, a test array was equipped with 10 AgReO4 crystals of various size and shape. The influence of the crystal quality as well as of different types of resin on rise time and energy resolution was investigated. C1 [Kraft-Bermuth, S.; Arnaboldi, C.; Ferri, E.; Nucciotti, A.; Pessina, G.; Previtali, E.; Schaeffer, D.; Sisti, M.] Univ Milano Bicocca, Dept Phys, Milan, Italy. [Kraft-Bermuth, S.; Arnaboldi, C.; Ferri, E.; Nucciotti, A.; Pessina, G.; Previtali, E.; Schaeffer, D.; Sisti, M.] Ist Nazl Fis Nucl, I-20133 Milan, Italy. [Kilbourne, C.] NASA, Goddard Space Flight Ctr, Greenbelt, MD USA. [Margesin, B.] ITC irst, Trento, Italy. [Margesin, B.] Ist Nazl Fis Nucl, Padua, Italy. [McCammon, D.] Univ Wisconsin, Madison, WI USA. [Monfardini, A.] Inst Louis Neel, Grenoble, France. RP Kraft-Bermuth, S (reprint author), Univ Milano Bicocca, Dept Phys, Milan, Italy. EM saskia.kraft@mib.infn.it RI Kraft-Bermuth, Saskia/G-4007-2012; Nucciotti, Angelo/I-8888-2012; Ferri, Elena/L-8531-2014; Margesin, Benno/K-5826-2015; Sisti, Monica/B-7550-2013; OI Kraft-Bermuth, Saskia/0000-0002-0864-7912; Nucciotti, Angelo/0000-0002-8458-1556; Ferri, Elena/0000-0003-1425-3669; Margesin, Benno/0000-0002-1120-3968; Sisti, Monica/0000-0003-2517-1909; Pessina, Gianluigi Ezio/0000-0003-3700-9757 NR 4 TC 3 Z9 3 U1 0 U2 1 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD MAY PY 2008 VL 151 IS 3-4 BP 619 EP 622 DI 10.1007/s10909-008-9715-8 PG 4 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 277HB UT WOS:000254202200005 ER PT J AU Schaeffer, D Arnaboldi, C Ceruti, G Ferri, E Kilbourne, C Kraft-Bermuth, S Margesin, B McCammon, D Monfardini, A Nucciotti, A Pessina, G Previtali, E Sisti, M AF Schaeffer, D. Arnaboldi, C. Ceruti, G. Ferri, E. Kilbourne, C. Kraft-Bermuth, S. Margesin, B. McCammon, D. Monfardini, A. Nucciotti, A. Pessina, G. Previtali, E. Sisti, M. TI Cryogenic design of the setup for MARE-1 in milan SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article AB A large worldwide collaboration is growing around the project of Micro-calorimeter Arrays for a Rhenium Experiment (MARE) for a direct calorimetric measurement of the neutrino mass. To validate the use of cryogenic detectors by checking the presence of unexpected systematic errors, two first experiments are planned using the available techniques composed of arrays of 300 detectors to measure 10(10) events in a reasonable time of 3 years (step MARE-1) to reach a sensitivity on the neutrino mass of similar to 2 eV/c(2). Our experiment in Milan is based on compensated doped silicon implanted thermistor arrays made in NASA/GSFC and on AgReO4 crystals. We present here the design of the cryogenic system that integrates all the requirements for such experiment (electronics for high impedances, low parasitic capacitances, low micro-phonic noise). C1 [Schaeffer, D.; Arnaboldi, C.; Ceruti, G.; Ferri, E.; Kraft-Bermuth, S.; Nucciotti, A.; Pessina, G.; Previtali, E.; Sisti, M.] Univ Milano Bicocca, Dept Phys, Milan, Italy. [Schaeffer, D.; Arnaboldi, C.; Ceruti, G.; Ferri, E.; Kraft-Bermuth, S.; Nucciotti, A.; Pessina, G.; Previtali, E.; Sisti, M.] Ist Nazl Fis Nucl, I-20133 Milan, Italy. [Margesin, B.; Monfardini, A.] NASA, Goddard Space Flight Ctr, Greenbelt, MA USA. [Margesin, B.; Monfardini, A.] ITC irst, Trento, Italy. [Margesin, B.; Monfardini, A.] Ist Nazl Fis Nucl, Padua, Italy. [McCammon, D.] Univ Wisconsin, Madison, WI USA. RP Schaeffer, D (reprint author), Univ Milano Bicocca, Dept Phys, Milan, Italy. EM david.schaeffer@mib.infn.it RI Kraft-Bermuth, Saskia/G-4007-2012; Nucciotti, Angelo/I-8888-2012; Ferri, Elena/L-8531-2014; Margesin, Benno/K-5826-2015; Sisti, Monica/B-7550-2013; OI Kraft-Bermuth, Saskia/0000-0002-0864-7912; Nucciotti, Angelo/0000-0002-8458-1556; Ferri, Elena/0000-0003-1425-3669; Margesin, Benno/0000-0002-1120-3968; Sisti, Monica/0000-0003-2517-1909; Pessina, Gianluigi Ezio/0000-0003-3700-9757 NR 2 TC 5 Z9 5 U1 0 U2 1 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD MAY PY 2008 VL 151 IS 3-4 BP 623 EP 628 DI 10.1007/s10909-008-9719-4 PG 6 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 277HB UT WOS:000254202200006 ER PT J AU Schlaerth, J Vayonakis, A Day, P Glenn, J Gao, J Golwala, S Kumar, S Leduc, H Mazin, B Vaillancourt, J Zmuidzinas, J AF Schlaerth, J. Vayonakis, A. Day, P. Glenn, J. Gao, J. Golwala, S. Kumar, S. LeDuc, H. Mazin, B. Vaillancourt, J. Zmuidzinas, J. TI A millimeter and submillimeter kinetic inductance detector camera SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article DE radio telescopes and instrumentation; heterodyne receivers; superconducting infrared; submillimeter and millimeter wave detectors ID ARRAYS AB We present results from a demonstration camera using Microwave Kinetic Inductance Detectors (MKIDs) (Day et al. in Nature 425, 817-821, [2003]) at the Caltech Submillimeter Observatory. The focal plane consists of 16 two-color (240 and 350 GHz) pixels. Each pixel is a phased-array of slot dipole antenna whose output power is coupled to MKIDs via in-line color-defining bandpass filters. A prototype software-defined radio system was used to read out up to four MKIDs simultaneously. We obtained maps of Jupiter, Saturn, and G34.3 and demonstrated sensitivities of approximately 1 Jy s(1/2) and 10 Jy s(1/2) in the two bands, respectively, limited by detector noise due to a low-efficiency optical train. We anticipate that a second engineering run in 2008 with a 36-element, 4-color array and an optimized optical train will be background limited at 240, 270, 350, and 400 GHz. We are undertaking the construction of a full-size MKID camera with 576 four-color spatial pixels and using 2304 MKIDs readout by an expanded software-defined radio system. C1 [Schlaerth, J.; Glenn, J.] Univ Colorado, Ctr Astrophys & Space Astron, Boulder, CO USA. [Vayonakis, A.; Gao, J.; Golwala, S.; Kumar, S.; Vaillancourt, J.; Zmuidzinas, J.] CALTECH, Pasadena, CA 91125 USA. [Day, P.; LeDuc, H.; Mazin, B.] NASA, Jet Prop Lab, Pasadena, CA 91109 USA. RP Schlaerth, J (reprint author), Univ Colorado, Ctr Astrophys & Space Astron, 593 UCB, Boulder, CO USA. EM James.Schlaerth@Colorado.edu RI Mazin, Ben/B-8704-2011 OI Mazin, Ben/0000-0003-0526-1114 NR 4 TC 25 Z9 26 U1 0 U2 1 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD MAY PY 2008 VL 151 IS 3-4 BP 684 EP 689 DI 10.1007/s10909-008-9728-3 PG 6 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 277HB UT WOS:000254202200016 ER PT J AU Niemack, MD Zhao, Y Wollack, E Thornton, R Switzer, ER Swetz, DS Staggs, ST Page, L Stryzak, O Moseley, H Marriage, TA Limon, M Lau, JM Klein, J Kaul, M Jarosik, N Irwin, KD Hincks, AD Hilton, GC Halpern, M Fowler, JW Fisher, RP Dunner, R Doriese, WB Dicker, SR Devlin, MJ Chervenak, J Burger, B Battistelli, ES Appel, J Amiri, M Allen, C Aboobaker, AM AF Niemack, M. D. Zhao, Y. Wollack, E. Thornton, R. Switzer, E. R. Swetz, D. S. Staggs, S. T. Page, L. Stryzak, O. Moseley, H. Marriage, T. A. Limon, M. Lau, J. M. Klein, J. Kaul, M. Jarosik, N. Irwin, K. D. Hincks, A. D. Hilton, G. C. Halpern, M. Fowler, J. W. Fisher, R. P. Duenner, R. Doriese, W. B. Dicker, S. R. Devlin, M. J. Chervenak, J. Burger, B. Battistelli, E. S. Appel, J. Amiri, M. Allen, C. Aboobaker, A. M. TI A kilopixel array of TES bolometers for ACT: Development, testing, and first light SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article DE TES; bolometer; detector array; astrophysics; cosmology AB The Millimeter Bolometer Array Camera (MBAC) will be installed on the 6-meter Atacama Cosmology Telescope (ACT) in late 2007. For the first season of observations, MBAC will comprise a 145 GHz diffraction-limited, 1024-pixel, focal plane array of Transition Edge Sensor (TES) Bolometers. This will be the largest array of pop-up-detector bolometers ever fielded as well as one of the largest arrays of TES bolometers. We discuss the design specifications for the array and pre-assembly testing procedures for the cryogenic components. We present dark measurements of the TES bolometer properties of numerous 32-pixel columns that have been assembled into the first kilopixel array for ACT, as well as optical measurements made with our 256-pixel prototype array, including first light measurements on ACT. C1 [Niemack, M. D.; Zhao, Y.; Switzer, E. R.; Staggs, S. T.; Page, L.; Stryzak, O.; Marriage, T. A.; Lau, J. M.; Jarosik, N.; Hincks, A. D.; Fowler, J. W.; Fisher, R. P.; Appel, J.] Princeton Univ, Dept Phys, Princeton, NJ 08544 USA. [Wollack, E.; Moseley, H.; Chervenak, J.; Allen, C.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Thornton, R.; Swetz, D. S.; Limon, M.; Klein, J.; Kaul, M.; Dicker, S. R.; Devlin, M. J.] Univ Penn, Dept Phys, Philadelphia, PA 19104 USA. [Halpern, M.; Burger, B.; Battistelli, E. S.; Amiri, M.] Univ British Columbia, Dept Phys & Astron, Vancouver, BC V6T 1Z1, Canada. [Irwin, K. D.; Hilton, G. C.; Doriese, W. B.] Natl Inst Stand & Technol, Boulder, CO 80305 USA. [Duenner, R.] Univ Catolica, Santiago, Chile. [Aboobaker, A. M.] Univ Minnesota, Sch Phys & Astron, Minneapolis, MN 55455 USA. RP Niemack, MD (reprint author), Princeton Univ, Dept Phys, Princeton, NJ 08544 USA. EM mniemack@princeton.edu RI Moseley, Harvey/D-5069-2012; Klein, Jeffrey/E-3295-2013; Wollack, Edward/D-4467-2012; OI Wollack, Edward/0000-0002-7567-4451; Limon, Michele/0000-0002-5900-2698 NR 11 TC 26 Z9 26 U1 0 U2 5 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD MAY PY 2008 VL 151 IS 3-4 BP 690 EP 696 DI 10.1007/s10909-008-9729-2 PG 7 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 277HB UT WOS:000254202200017 ER PT J AU Mitsuda, K Kelley, R McCammon, D den Herder, JW Ohashi, T AF Mitsuda, Kazuhisa Kelley, Richard McCammon, Dan den Herder, Jan-Willem Ohashi, Takaya TI Microcalorimeter instruments for the Spectrum-R(X)G and NeXT missions SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article DE high resolution X-ray spectroscopy; microcaloriemter array; X-ray astronomy; space cryogenics ID SUZAKU AB X-ray spectrometers utilizing a microcalorimeter array are presently under study for the Russian Spectrum R-G (or Spectrum-X-Gamma) mission, which is to be launched in 2011, and for the Japanese NeXT (New X-ray Telescope or Non-thermal energy eXploration Telescope) mission, whose launch is expected to be in 2012 to 2015. The primary instrument of Spectrum R-G is eROSITA, which will make an all sky survey in the 0.1-10 keV range using an array of seven telescopes and X-ray CCD cameras. The mission also carries smaller instruments, a wide-field monitor (Lobster) and a hard X-ray telescope (ART). We are proposing SXC-the Spectrum-X Calorimeter-to obtain spatially-resolved precision spectra of a number of nearby massive clusters of galaxies during an initial 6-month pointed phase, and to obtain a detailed spectral map of the soft X-ray diffuse background during the 4-year survey phase. The NeXT mission is a combination of wide band X-ray spectroscopy provided by multi-layer coating, focusing X-ray mirrors and pixel detectors, and high resolution soft X-ray spectroscopy by microcalorimeter instrument, SXS-the Soft X-ray Spectrometer. The effective area of the SXS is about 20 times larger than that of SXC at the iron K line energy (6.7 keV) while the solid angle of the field of view is by a factor of 15 smaller. One of the major scientific objectives of SXS is to determine turbulent and/or macroscopic velocities in the hot gas of distant clusters of galaxies. Both of the instruments will use 6x6 microcalorimeter array similar to the one launched on Suzaku, while both will adopt a He-3 Joule Thomson cooler and two-stage Stirling cycle in the cryogenic systems. The He-3 Joule Thomson cooler provides a thermal guard to liquid He but it can also work as a 1.8 K heat bath for the adiabatic demagnetization refrigerator. C1 [Mitsuda, Kazuhisa] ISAS JAXA, Sagamihara, Kanagawa, Japan. [Kelley, Richard] NASA, Greenbelt, MD USA. [McCammon, Dan] Univ Wisconsin, Madison, WI USA. [den Herder, Jan-Willem] SRON, Utrecht, Netherlands. [Ohashi, Takaya] Tokyo Metropolitan Univ, Hachioji, Tokyo, Japan. RP Mitsuda, K (reprint author), ISAS JAXA, Sagamihara, Kanagawa, Japan. EM mitsuda@astro.isas.jaxa.jp RI Mitsuda, Kazuhisa/C-2649-2008; Kelley, Richard/K-4474-2012; XRAY, SUZAKU/A-1808-2009 NR 9 TC 2 Z9 3 U1 0 U2 2 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2291 EI 1573-7357 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD MAY PY 2008 VL 151 IS 3-4 BP 703 EP 708 DI 10.1007/s10909-008-9737-2 PG 6 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 277HB UT WOS:000254202200019 ER PT J AU Staguhn, J Allen, C Benford, D Sharp, E Ames, T Arendt, R Chuss, D Dwek, E Kovacs, A Maher, S Marx, C Miller, T Moseley, SH Navarro, S Sievers, A Voellmer, G Wollack, E AF Staguhn, Johannes Allen, Christine Benford, Dominic Sharp, Elmer Ames, Troy Arendt, Rick Chuss, David Dwek, Eli Kovacs, Attila Maher, Stephen Marx, Catherine Miller, Tim Moseley, S. Harvey Navarro, Santiago Sievers, Albrecht Voellmer, George Wollack, Edward TI GISMO, a 2 mm bolometer camera optimized for the study of high redshift galaxies SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article DE millimeter astronomy; bolometer array; dust emission; galaxies ID MULTIPLEXER; TELESCOPE AB The 2 mm spectral range provides a unique terrestrial window enabling ground based observations of the earliest active dusty galaxies in the universe and thereby allowing a better constraint on the star formation rate in these objects. We have built GISMO (the Goddard-IRAM Superconducting 2-Millimeter Observer), a 2 mm, 128 element superconducting Transition Edge Sensor (TES) based bolometer camera for the IRAM 30 m telescope in Spain. The camera uses an 8x16 planar array of multiplexed TES bolometers, which incorporates our recently designed Backshort Under Grid (BUG) architecture, described elsewhere. The optical design incorporates a 100 mm (4 inches) diameter silicon lens cooled to 4 K, which provides the required fast beam of 0.9 lambda/D. With this spatial sampling, GISMO will be very efficient at detecting sources serendipitously in large sky surveys, while the capability for diffraction-limited observations is preserved. With the background limited performance of the detectors, the camera provides significantly greater imaging sensitivity and mapping speed at this wavelength than has previously been possible. The major scientific driver for the instrument is to provide the IRAM 30 m telescope with the capability to rapidly observe galactic and extragalactic dust emission, in particular from high-z Ultra Luminous Infrared Galaxies (ULIRGs) and quasars, even in the summer season. The instrument will fill in the SEDs of high redshift galaxies at the Rayleigh-Jeans part of the dust emission spectrum, even at the highest redshifts. Our source count models predict that GISMO will serendipitously detect one galaxy every four hours on the blank sky, and that one quarter of these galaxies will be at a redshift of z 6.5. We expect to install GISMO at the 30 m telescope in the second half of 2007. C1 [Staguhn, Johannes; Allen, Christine; Benford, Dominic; Sharp, Elmer; Ames, Troy; Arendt, Rick; Chuss, David; Dwek, Eli; Maher, Stephen; Marx, Catherine; Miller, Tim; Moseley, S. Harvey; Voellmer, George; Wollack, Edward] NASA, GSFC, Goddard, MA USA. [Staguhn, Johannes] Univ Maryland, College Pk, MD 20742 USA. [Kovacs, Attila] MPIfR, Bonn, Germany. [Navarro, Santiago; Sievers, Albrecht] IRAM, E-18012 Granada, Spain. RP Staguhn, J (reprint author), NASA, GSFC, Goddard, MA USA. EM staguhn@milkyway.gsfc.nasa.gov RI Dwek, Eli/C-3995-2012; Benford, Dominic/D-4760-2012; Moseley, Harvey/D-5069-2012; Chuss, David/D-8281-2012; Kovacs, Attila/C-1171-2010; Wollack, Edward/D-4467-2012; OI Benford, Dominic/0000-0002-9884-4206; Kovacs, Attila/0000-0001-8991-9088; Wollack, Edward/0000-0002-7567-4451; Arendt, Richard/0000-0001-8403-8548 NR 7 TC 16 Z9 16 U1 1 U2 2 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD MAY PY 2008 VL 151 IS 3-4 BP 709 EP 714 DI 10.1007/s10909-008-9733-6 PG 6 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 277HB UT WOS:000254202200020 ER PT J AU McCammon, D Barger, K Brandl, DE Brekosky, RP Crowder, SG Gygax, JD Kelley, RL Kilbourne, CA Lindeman, MA Porter, FS Rocks, LE Szymkowiak, AE AF McCammon, D. Barger, K. Brandl, D. E. Brekosky, R. P. Crowder, S. G. Gygax, J. D. Kelley, R. L. Kilbourne, C. A. Lindeman, M. A. Porter, F. S. Rocks, L. E. Szymkowiak, A. E. TI The X-ray quantum calorimeter sounding rocket experiment: Improvements for the next flight SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article DE microcalorimeters; X-ray astronomy; X-ray instrumentation AB We have developed a new calorimeter array to increase our collecting area by a factor of four. The 6x6 pixel device has a total area of 144 mm(2), making it one of the largest X-ray microcalorimeter arrays yet constructed. A relatively thin high-z absorber consisting of a 0.7 mu m HgTe layer supported on 15 mu m high-purity silicon provides good efficiency up to photon energies of 1.5 keV. The heat capacity of this composite is low enough to obtain an energy resolution of similar to 6 eV FWHM on the 2 mmx2 mm pixels when operated at a base temperature of 50 mK. The infrared blocking filters have also been improved. Room temperature radiation must be attenuated by about 9 orders of magnitude between 2 mu m and 2 cm to avoid having photon shot noise dominate the detectornoise. Accomplishing this while maintaining a high transmission for very soft X-rays that can penetrate only a few mu m(-2) is a problem common to all soft X-ray calorimeters that observe external targets. We are constructing monolithic silicon two-layer support meshes with a 350 mu m pitch front layer on a 5 mm pitch backing layer. These are 98% open and have > 95% effective transmission over a 60 degrees field of view, while providing robust support for 38 mm diameter filters consisting of 20 nm of aluminum on 50 nm of polyimide. Five of these filters in series provide the necessary infrared attenuation. Integral deicing heaters are ion implanted in the fine mesh to remove contamination when necessary. C1 [McCammon, D.; Barger, K.; Brandl, D. E.; Crowder, S. G.; Lindeman, M. A.; Rocks, L. E.] Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. [Brekosky, R. P.; Gygax, J. D.; Kelley, R. L.; Kilbourne, C. A.; Porter, F. S.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Szymkowiak, A. E.] Yale Univ, New Haven, CT 06511 USA. RP McCammon, D (reprint author), Univ Wisconsin, Dept Phys, 1150 Univ Ave, Madison, WI 53706 USA. EM mccammon@wisp.physics.wisc.edu RI Porter, Frederick/D-3501-2012; Kelley, Richard/K-4474-2012 OI Porter, Frederick/0000-0002-6374-1119; NR 7 TC 12 Z9 12 U1 0 U2 1 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD MAY PY 2008 VL 151 IS 3-4 BP 715 EP 720 DI 10.1007/s10909-008-9734-5 PG 6 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 277HB UT WOS:000254202200021 ER PT J AU Figueroa-Feliciano, E Bandler, SR Bautz, M Brown, G Deiker, S Doriese, WB Flanagan, K Galeazzi, M Hilton, GC Hwang, U Irwin, KD Kallman, T Kelley, RL Kilbourne, CA Kissel, S Levine, A Loewenstein, M Martinez-Galarce, D McCammon, D Mushotzky, R Petre, R Porter, FS Reistema, CD Saab, T Serlemitsos, P Schulz, N Smith, R Ullom, JN AF Figueroa-Feliciano, E. Bandler, S. R. Bautz, M. Brown, G. Deiker, S. Doriese, W. B. Flanagan, K. Galeazzi, M. Hilton, G. C. Hwang, U. Irwin, K. D. Kallman, T. Kelley, R. L. Kilbourne, C. A. Kissel, S. Levine, A. Loewenstein, M. Martinez-Galarce, D. McCammon, D. Mushotzky, R. Petre, R. Porter, F. S. Reistema, C. D. Saab, T. Serlemitsos, P. Schulz, N. Smith, R. Ullom, J. N. TI Micro-X: Mission overview and science goals SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article DE TES; microcalorimeter; micro-X; supernova remnants; rocket AB Micro-X, the High-Resolution Microcalorimeter X-ray Imaging Rocket, is a sounding rocket space telescope that will combine a transition-edge-sensor (TES) X-ray microcalorimeter array with a conical imaging mirror to obtain high spectral resolution images of extended and point X-ray sources. Microcalorimeters measure the energy of an absorbed photon by sensing the increase in temperature of the sensor from the thermalization of the absorbed photon's energy. The advantages and scientific promise of this technology have fueled active development for the past 20 years. We will leverage this development and take the next step by producing a flight-qualified system that will serve as a pathfinder for future missions. Our scientific program will initially focus on extended sources, for which our high-spectral-resolution observations have distinct advantages over other technologies. For our initial flight, we will observe the bright eastern knot in the Puppis A remnant, a site of complex cloud-shock interactions and ejecta enrichment. A Micro-X observation of the bright eastern knot of Puppis A will obtain a line-dominated spectrum with 90,000 counts collected in 300 seconds at 2 eV resolution across the 0.3-2.5 keV band. C1 [Figueroa-Feliciano, E.] MIT, Dept Phys, Cambridge, MA 02139 USA. [Figueroa-Feliciano, E.; Bautz, M.; Kissel, S.; Levine, A.; Schulz, N.] MIT, Kavli Inst Astrophys & Space Res, Cambridge, MA 02139 USA. [Flanagan, K.] Space Telescope Sci Inst, Baltimore, MD 21218 USA. [Bandler, S. R.; Hwang, U.; Kallman, T.; Kelley, R. L.; Kilbourne, C. A.; Loewenstein, M.; Mushotzky, R.; Petre, R.; Porter, F. S.; Serlemitsos, P.; Smith, R.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20770 USA. [Bandler, S. R.; Loewenstein, M.] Univ Maryland, Dept Astron, College Pk, MD 20742 USA. [Brown, G.] Lawrence Livermore Natl Lab, High Energy Dens Phys & Astrophys Div, Livermore, CA USA. [Deiker, S.; Martinez-Galarce, D.] Lockheed Martin Solar & Astrophys Lab, Palo Alto, CA 94304 USA. [Doriese, W. B.; Hilton, G. C.; Irwin, K. D.; Reistema, C. D.; Ullom, J. N.] Natl Inst Stand & Technol, Boulder, CO 80305 USA. [Galeazzi, M.] Univ Miami, Dept Phys, Coral Gables, FL 33146 USA. [McCammon, D.] Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. [Saab, T.] Univ Florida, Dept Phys, Gainesville, FL 32611 USA. RP Figueroa-Feliciano, E (reprint author), MIT, Dept Phys, Cambridge, MA 02139 USA. EM enectali@mit.edu RI Bandler, Simon/A-6258-2010; Porter, Frederick/D-3501-2012; Kelley, Richard/K-4474-2012 OI Bandler, Simon/0000-0002-5112-8106; Porter, Frederick/0000-0002-6374-1119; NR 2 TC 5 Z9 5 U1 0 U2 3 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD MAY PY 2008 VL 151 IS 3-4 BP 740 EP 745 DI 10.1007/s10909-008-9732-7 PG 6 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 277HB UT WOS:000254202200025 ER PT J AU Doriese, WB Ullom, JN Beall, JA Duncan, WD Ferreira, L Hilton, GC Horansky, RD Irwin, KD Mates, JAB Reintsema, CD Schmidt, DR Vale, LR Xu, Y Zink, BL Bacrania, MK Hoover, AS Rudy, CR Rabin, MW Kilbourne, CA Boyce, KR Brown, LE King, JM Porter, FS AF Doriese, W. B. Ullom, J. N. Beall, J. A. Duncan, W. D. Ferreira, L. Hilton, G. C. Horansky, R. D. Irwin, K. D. Mates, J. A. B. Reintsema, C. D. Schmidt, D. R. Vale, L. R. Xu, Y. Zink, B. L. Bacrania, M. K. Hoover, A. S. Rudy, C. R. Rabin, M. W. Kilbourne, C. A. Boyce, K. R. Brown, L. E. King, J. M. Porter, F. S. TI Toward a 256-pixel array of gamma-ray microcalorimeters for nuclear-materials analysis SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article DE gamma-ray spectrometer; microcalorimeter; transition-edge sensor ID TRANSITION-EDGE SENSORS; EV ENERGY RESOLUTION; MULTIPLEXER; SYSTEM AB We are developing a gamma-ray spectrometer for the analysis of nuclear materials based on an array of superconducting transition-edge-sensor microcalorimeters. The instrument will include eight columns of time-division-SQUID multiplexing circuitry capable of reading out 256 sensors. Our most recent sensors are bulk (1.5 mm square x 0.25 mm thick) superconducting Sn absorbers glued to Mo/Cu bilayer thermometers. When fully populated, the active area of the spectrometer will be 5.76 cm(2), and the maximum count rate of the array will approach 20 kHz. Thus, our spectrometer will be comparable to the state-of-the-art 100 keV high-purity-Ge detector in count rate and collecting area, but with an order of magnitude better energy resolution. Half the detectors will be optimized for operation up to 100 keV, and the other half for operation up to 200 keV. A version of the spectrometer with a partially populated detector array was delivered to Los Alamos National Laboratory in June, 2007. We describe the present status of that instrument. In addition, we review results from a prototype array of 14 detectors that achieved 47 eV average energy resolution (full width at half maximum at 103 keV) and 25 eV resolution in the best detector. An important application of this technology is determining the total Pu content in spent reactor fuel without detailed knowledge of the reactor's operating history. C1 [Doriese, W. B.; Ullom, J. N.; Beall, J. A.; Duncan, W. D.; Ferreira, L.; Hilton, G. C.; Horansky, R. D.; Irwin, K. D.; Mates, J. A. B.; Reintsema, C. D.; Schmidt, D. R.; Vale, L. R.; Xu, Y.; Zink, B. L.] Natl Inst Stand & Technol, Boulder, CO 80303 USA. [Bacrania, M. K.; Hoover, A. S.; Rudy, C. R.; Rabin, M. W.] Los Alamos Natl Lab, Los Alamos, NM 87545 USA. [Kilbourne, C. A.; Boyce, K. R.; Brown, L. E.; King, J. M.; Porter, F. S.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Doriese, WB (reprint author), Natl Inst Stand & Technol, 325 Broadway, Boulder, CO 80303 USA. EM doriese@boulder.nist.gov RI Porter, Frederick/D-3501-2012; OI Porter, Frederick/0000-0002-6374-1119; Zink, Barry/0000-0001-7732-532X NR 12 TC 6 Z9 6 U1 0 U2 1 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD MAY PY 2008 VL 151 IS 3-4 BP 754 EP 759 DI 10.1007/s10909-008-9750-5 PG 6 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 277HB UT WOS:000254202200027 ER PT J AU Duncan, WD Schwall, RE Irwin, KD Beall, JA Reintsema, CD Doriese, W Cho, HM Estey, B Chattopadhyay, G Ade, P Tucker, C AF Duncan, W. D. Schwall, R. E. Irwin, K. D. Beall, J. A. Reintsema, C. D. Doriese, William Cho, Hsiao-Mei Estey, Brian Chattopadhyay, Goutam Ade, Peter Tucker, Carole TI An optical system for body imaging from a distance using near-TeraHertz frequencies SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article DE THz; stand-off imaging; IED; passive; TES; microwave readout; SQUID's AB We present the outline of the optical design of a TeraHertz (THz) imager for the detection of shrapnel-loaded improvised explosive devices (IED) devices at "stand-off" distances of 14-26 meters. The system will use 4 antenna-coupled TES detector arrays of 16 by 16 pixels cooled in a cryogen-free system with microwave readout to see beneath clothing at non-lethal detonation distances. A spatial resolution of similar to 10 mm and close to video frame rates is anticipated. C1 [Duncan, W. D.; Schwall, R. E.; Irwin, K. D.; Beall, J. A.; Reintsema, C. D.; Doriese, William; Cho, Hsiao-Mei; Estey, Brian] NIST, Quantum Sensors Project, Boulder, CO 80305 USA. [Chattopadhyay, Goutam] Jet Propuls Lab, Pasadena, CA 91109 USA. [Ade, Peter; Tucker, Carole] Cardiff Univ, Sch Phys & Astron, Cardiff CF24 3AA, S Glam, Wales. RP Duncan, WD (reprint author), NIST, Quantum Sensors Project, Mailcode 817-03,325 Broadway, Boulder, CO 80305 USA. EM wduncan@boulder.nist.gov NR 8 TC 4 Z9 7 U1 1 U2 4 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD MAY PY 2008 VL 151 IS 3-4 BP 777 EP 783 DI 10.1007/s10909-008-9746-1 PG 7 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 277HB UT WOS:000254202200031 ER PT J AU Hahn, I Day, P Bumble, B Leduc, HG AF Hahn, I. Day, P. Bumble, B. LeDuc, H. G. TI Recent results of a new microwave SQUID multiplexer SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article DE SQUID multiplexer; TES bolometer ID ARRAYS; SENSORS AB We present recent results of a prototype microwave SQUID multiplexer containing four SQUIDs coupled to GHz frequency resonant circuits and fed with a single microwave readout line. The system is operating at a readout frequency range of 8-10 GHz. All four SQUIDs share a common DC bias and modulation lines. A new modulation scheme is tested to eliminate the need for individual flux biasing of the SQUIDs, which extends the dynamic range of the readout. In this scheme a common modulation signal is imposed on each SQUID and the received signal is demodulated at one and two times the modulation frequency to maintain sensitivity at any flux state. We also demonstrated a microwave RF bias scheme eliminating the necessity of the DC current bias to the SQUID. Our preliminary performance tests at 4.2 K show that the input noise of the device is similar to 5 pA/root Hz. C1 [Hahn, I.; Day, P.; Bumble, B.; LeDuc, H. G.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Hahn, I (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Inseob.Hahn@jpl.nasa.gov NR 7 TC 6 Z9 6 U1 2 U2 3 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD MAY PY 2008 VL 151 IS 3-4 BP 934 EP 939 DI 10.1007/s10909-008-9773-y PG 6 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 277HB UT WOS:000254202200056 ER PT J AU Oh, L Allen, C Kelley, R AF Oh, L. Allen, C. Kelley, R. TI Fabrication of a thermally isolated and pre-amplified transistor module with polyimide micro-wires for cryogenic detectors SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article DE JFET; bolometer; microcalorimeter; thermal isolation; suspension; DRIE; heaters; polyimide AB We report a pre-amplifying junction field effect transistor (JFET) module on a chip for cryogenic applications such as bolometer and X-ray microcalorimeter. In order to maintain the optimum performance of the JFETs at 130 K, the module has built-in aluminum micro-heaters while the JFETs are thermally isolated from a heat sink. The thermal isolation is achieved by suspending a micromachined silicon support platform (6 mu m thick) with polyimide wires. A layer of aluminum electrodes is patterned on top of the polyimide wires for electrical contacts and on top of the silicon platform for the heaters. This process involves reactive-ion-etching (RIE) of silicon and polyimide, patterning of aluminum electrodes over the polyimide, back side deep-reactive-ion-etching (DRIE) of silicon, and releasing of the modules. In this paper, we describe a micromachining process of the JFET modules on silicon-on-insulator (SOI) wafers. C1 [Oh, L.; Allen, C.; Kelley, R.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Oh, L.] MEI Technol Inc, Seabrook, MD 20706 USA. RP Oh, L (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM loh@pop500.gsfc.nasa.gov RI Kelley, Richard/K-4474-2012 NR 2 TC 1 Z9 1 U1 0 U2 2 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD MAY PY 2008 VL 151 IS 3-4 BP 1003 EP 1008 DI 10.1007/s10909-008-9778-6 PG 6 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 277HB UT WOS:000254202200067 ER PT J AU Smith, SJ Bandler, SR Brown, AD Chervenak, JA Figueroa-Feliciano, E Finkbeiner, F Iyomoto, N Kelley, RL Kilbourne, CA Porter, FS AF Smith, S. J. Bandler, S. R. Brown, A. -D. Chervenak, J. A. Figueroa-Feliciano, E. Finkbeiner, F. Iyomoto, N. Kelley, R. L. Kilbourne, C. A. Porter, F. S. TI Optimizing arrays of position-sensitive TESs SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article DE position-sensitive detector; optimal filter; signal processing ID TRANSITION-EDGE SENSORS; RESOLUTION AB We are developing position-sensitive transition-edge sensors (PoSTs) for future X-ray astronomy missions such as NASAs Constellation-X. The PoST consists of 1 or more transitions-edge sensors (TESs) thermally connected to a large X-ray absorber, which through heat diffusion, gives rise to position dependence. The development of PoSTs is motivated by the desire to achieve the largest focal-plane coverage with the fewest number of readout channels. In this paper, we investigate optimized signal processing algorithms for single channel PoSTs or 'Hydras' (consisting of 4-absorbers connected to 1 TES). Using simulated data, we investigate the impact different parameters such as the thermal conductances and the inductance of the bias circuit have on device performance. C1 [Figueroa-Feliciano, E.] MIT, Kavli Inst Space Res, Cambridge, MA 02139 USA. [Smith, S. J.; Bandler, S. R.; Brown, A. -D.; Chervenak, J. A.; Finkbeiner, F.; Iyomoto, N.; Kelley, R. L.; Kilbourne, C. A.; Porter, F. S.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Smith, SJ (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM sjs@milkyway.gsfc.nasa.gov RI Brown, Ari/B-1693-2008; Bandler, Simon/A-6258-2010; Smith, Stephen/B-1256-2008; Porter, Frederick/D-3501-2012; Kelley, Richard/K-4474-2012 OI Bandler, Simon/0000-0002-5112-8106; Smith, Stephen/0000-0003-4096-4675; Porter, Frederick/0000-0002-6374-1119; NR 7 TC 3 Z9 3 U1 0 U2 2 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD MAY PY 2008 VL 151 IS 3-4 BP 1009 EP 1014 DI 10.1007/s10909-008-9779-5 PG 6 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 277HB UT WOS:000254202200068 ER PT J AU Benford, DJ Staguhn, JG Allen, CA Maher, SF Sharp, EH AF Benford, D. J. Staguhn, J. G. Allen, C. A. Maher, S. F. Sharp, E. H. TI Norton-corrected measurement of complex impedances of a large format bolometer array SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article DE superconducting bolometer; transition edge sensor; complex impedance; bolometer array AB We report on our efforts to measure simultaneously a well-calibrated complex impedance of a large number of detectors in a long wavelength bolometer array. The array is described in other presentations. A method for correcting the complex impedance measurements of bolometers and calorimeters has been presented by Lindeman et al. (Rev. Sci. Instrum. 78:043105, [2007]) using a Thevenin equivalent circuit to represent the bias network. We have built on this method for superconducting bolometers with a Norton equivalent circuit and have used it to improve our impedance data. We further describe our method for extracting a Norton-corrected complex impedance as a function of frequency from a stream of multiplexed time-ordered data. This method is well-suited to producing simultaneous complex impedance measurements for a large number of detectors. C1 [Benford, D. J.; Staguhn, J. G.; Allen, C. A.; Maher, S. F.; Sharp, E. H.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Benford, DJ (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM dominic.benford@nasa.gov RI Benford, Dominic/D-4760-2012 OI Benford, Dominic/0000-0002-9884-4206 NR 5 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD MAY PY 2008 VL 151 IS 3-4 BP 1015 EP 1021 DI 10.1007/s10909-008-9775-9 PG 7 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 277HB UT WOS:000254202200069 ER PT J AU Andrianov, V Beckert, K Beller, P Bleile, A Egelhof, P Gumberidze, A Ilieva, S Kiselev, O Kilbourne, C Kluge, HJ Kraft-Bermuth, S McCammon, D Meier, JP Reuschl, R Stohlker, T Trassinelli, M AF Andrianov, V. Beckert, K. Beller, P. Bleile, A. Egelhof, P. Gumberidze, A. Ilieva, S. Kiselev, O. Kilbourne, C. Kluge, H. -J. Kraft-Bermuth, S. McCammon, D. Meier, J. P. Reuschl, R. Stoehlker, T. Trassinelli, M. TI First experiments aiming for precise Lamb shift measurements on hydrogen-like heavy ions with low temperature calorimeters SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article DE calorimetric low temperature detectors for X-rays; test of QED ID X-RAY SPECTROSCOPY; URANIUM; ESR AB The precise determination of the Lamb shift in hydrogen-like heavy ions provides a sensitive test of quantum electrodynamics in very strong Coulomb fields, not accessible otherwise. To increase the accuracy of the Lamb shift measurement on stored heavy ions at the ESR storage ring at GSI, a calorimetric low temperature detector for hard X-rays was developed. A prototype array consisting of 8 pixels with silicon thermistors and Sn or Pb absorbers was applied in first experiments with stored U-238(91)+ and Pb-207(81+) ions interacting with an internal gas-jet target. In both experiments the Lyman-alpha lines were, for the first time by using calorimetric low temperature detectors, clearly identified in clean, almost background-free spectra. A total detection efficiency of 1x10(-7) for the Lyman-alpha lines was reached and an energy resolution of 115 eV was obtained under the present experimental conditions, which corresponds to a considerable improvement of about half an order of magnitude if compared to conventional Ge semiconductor detectors. Finally preliminary results of the data analysis and future perspectives are discussed. C1 [Andrianov, V.; Bleile, A.; Egelhof, P.; Ilieva, S.; Kiselev, O.; Kraft-Bermuth, S.; Meier, J. P.] Johannes Gutenberg Univ Mainz, Inst Phys, D-6500 Mainz, Germany. [Andrianov, V.; Beckert, K.; Beller, P.; Bleile, A.; Egelhof, P.; Gumberidze, A.; Ilieva, S.; Kiselev, O.; Kluge, H. -J.; Kraft-Bermuth, S.; Meier, J. P.; Reuschl, R.; Stoehlker, T.; Trassinelli, M.] Gesell Schwerionenforsch mbH, D-6100 Darmstadt, Germany. [Kilbourne, C.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [McCammon, D.] Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. RP Egelhof, P (reprint author), Johannes Gutenberg Univ Mainz, Inst Phys, D-6500 Mainz, Germany. EM p.egelhof@gsi.de RI Kraft-Bermuth, Saskia/G-4007-2012; Andrianov, Victor/J-5031-2012; Trassinelli, Martino/M-5326-2016 OI Kraft-Bermuth, Saskia/0000-0002-0864-7912; Trassinelli, Martino/0000-0003-4414-1801 NR 10 TC 11 Z9 11 U1 0 U2 5 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD MAY PY 2008 VL 151 IS 3-4 BP 1049 EP 1054 DI 10.1007/s10909-008-9792-8 PG 6 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 277HB UT WOS:000254202200074 ER PT J AU Porter, FS Beiersdorfer, P Brown, GV Doriese, W Gygax, J Kelley, RL Kilbourne, CA King, J Irwin, K Reintsema, C Ullom, J AF Porter, F. S. Beiersdorfer, P. Brown, G. V. Doriese, W. Gygax, J. Kelley, R. L. Kilbourne, C. A. King, J. Irwin, K. Reintsema, C. Ullom, J. TI The EBIT calorimeter spectrometer: A new, permanent user facility at the LLNL EBIT SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article DE X-ray; detector; cryogenic; astrophysics ID ASTRO-E2; EMISSION; XRS AB The EBIT Calorimeter Spectrometer (ECS) is currently being completed and will be installed at the EBIT facility at the Lawrence Livermore National Laboratory in October 2007. The ECS will replace the smaller XRS/EBIT microcalorimeter spectrometer that has been in almost continuous operation since 2000. The XRS/EBIT was based on a spare laboratory cryostat and an engineering model detector system from the Suzaku/XRS observatory program. The new ECS spectrometer was built to be a low maintenance, high performance implanted silicon microcalorimeter spectrometer with 4 eV resolution at 6 keV, 32 detector channels, 10 mu s event timing, and capable of uninterrupted acquisition sessions of over 60 hours at 50 mK. The XRS/EBIT program has been very successful, producing many results on topics such as laboratory astrophysics, atomic physics, nuclear physics, and calibration of the spectrometers for the National Ignition Facility. The ECS spectrometer will continue this work into the future with improved spectral resolution, integration times, and ease-of-use. We designed the ECS instrument with TES detectors in mind by using the same highly successful magnetic shielding as our laboratory TES cryostats. This design will lead to a future TES instrument at the LLNL EBIT. Here we discuss the legacy of the XRS/EBIT program, the performance of the new ECS spectrometer, and plans for a future TES instrument. C1 [Porter, F. S.; Gygax, J.; Kelley, R. L.; Kilbourne, C. A.; King, J.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Beiersdorfer, P.; Brown, G. V.] Lawrence Livermore Natl Lab, Livermore, CA USA. [Doriese, W.; Irwin, K.; Reintsema, C.; Ullom, J.] Natl Inst Stand & Technol, Boulder, CO USA. RP Porter, FS (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM porter@milkyway.gsfc.nasa.gov RI Porter, Frederick/D-3501-2012; Kelley, Richard/K-4474-2012; XRAY, SUZAKU/A-1808-2009 OI Porter, Frederick/0000-0002-6374-1119; NR 9 TC 12 Z9 12 U1 0 U2 2 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD MAY PY 2008 VL 151 IS 3-4 BP 1061 EP 1066 DI 10.1007/s10909-008-9788-4 PG 6 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 277HB UT WOS:000254202200076 ER PT J AU Lin, RQ Kuang, WJ AF Lin, Ray-Qing Kuang, Weijia TI Modeling nonlinear roll damping with a self-consistent, strongly nonlinear ship motion model SO JOURNAL OF MARINE SCIENCE AND TECHNOLOGY LA English DT Article DE roll motion; damping; numerical model ID WAVE-BODY INTERACTIONS; PART 1 AB Appropriate modeling of roll damping is one of the key issues in accurately predicting ship roll motion. The difficulties in modeling roll damping arise from the nonlinear nature of the phenomena. In this study, we report a new effort in modeling the bilge keel roll damping effect based on the blocking mechanisms of an object in the potential flow. This effect can be implemented as a component of appropriate ship motion models. We used our digital, self-consistent, ship experimental laboratory (DiSSEL) ship motion model to test its effectiveness in predicting ship roll motion. Our numerical experiment demonstrated clearly that the implementation of this roll damping component improves significantly the accuracy of numerical model results (the results were compared with ship experiment data from the Naval Surface Warfare Center, Carderock Division, Maneuvering and Seakeeping Facility). C1 [Lin, Ray-Qing] USN, Ctr Surface Warfare, Carderock Div, David Taylor Model Basin, Bethesda, MD 20817 USA. [Kuang, Weijia] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Lin, RQ (reprint author), USN, Ctr Surface Warfare, Carderock Div, David Taylor Model Basin, 9500 McArthur Blvd, Bethesda, MD 20817 USA. EM Ray.Lin@navy.mil RI Kuang, Weijia/K-5141-2012 OI Kuang, Weijia/0000-0001-7786-6425 NR 40 TC 9 Z9 10 U1 0 U2 9 PU SPRINGER TOKYO PI TOKYO PA 1-11-11 KUDAN-KITA, CHIYODA-KU, TOKYO, 102-0073, JAPAN SN 0948-4280 J9 J MAR SCI TECH-JAPAN JI J. Mar. Sci. Technol. PD MAY PY 2008 VL 13 IS 2 BP 127 EP 137 DI 10.1007/s00773-007-0262-9 PG 11 WC Engineering, Marine; Engineering, Civil SC Engineering GA 307MN UT WOS:000256323100004 ER PT J AU Kurtoglu, T Tumer, IY AF Kurtoglu, Tolga Tumer, Irem Y. TI A graph-based fault identification and propagation framework for functional design of complex systems SO JOURNAL OF MECHANICAL DESIGN LA English DT Article DE failure prevention; reliability engineering; risk based design; functional modeling; failure analysis; concept generation; configuration flow graph; simulation based design; model based design ID MULTIPLE FAULTS; DIAGNOSIS; ALGORITHMS AB In this paper, the functional-failure identification and propagation (FFIP) framework is introduced as a novel approach for,evaluating and assessing functional-failure risk of physical systems during conceptual design. The task of FFIP is to estimate potential faults and their propagation paths under critical event scenarios. The framework is based on combining hierarchical system models of functionality and configuration, with behavioral simulation and qualitative reasoning. The main advantage of the method is that it allows the analysis of functional failures and fault propagation at a highly abstract system concept level before any potentially high-cost design commitments are made. As a result, it provides the designers and system engineers with a means of designing out functional failures where possible and designing in the capability to detect and mitigate failures early on in the design process. Application of the presented method to a fluidic system example demonstrates these capabilities. C1 [Tumer, Irem Y.] Oregon State Univ, Sch Mech Ind & Mfg Engn, Corvallis, OR 97331 USA. [Kurtoglu, Tolga] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Tumer, IY (reprint author), Oregon State Univ, Sch Mech Ind & Mfg Engn, 204 Rogers Hall, Corvallis, OR 97331 USA. NR 50 TC 42 Z9 43 U1 3 U2 14 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 1050-0472 J9 J MECH DESIGN JI J. Mech. Des. PD MAY PY 2008 VL 130 IS 5 AR 051401 DI 10.1115/1.2885181 PG 8 WC Engineering, Mechanical SC Engineering GA 297VD UT WOS:000255644600003 ER PT J AU Shinoda, T Roundy, PE Kiladis, GN AF Shinoda, Toshiaki Roundy, Paul E. Kiladis, George N. TI Variability of intraseasonal Kelvin waves in the equatorial Pacific Ocean SO JOURNAL OF PHYSICAL OCEANOGRAPHY LA English DT Article ID MADDEN-JULIAN OSCILLATION; TROPICAL WESTERN PACIFIC; INDIAN OCEANS; EL-NINO; SURFACE FLUXES; MODEL; TEMPERATURE; DYNAMICS; IMPACT; CYCLE AB Previous observational work has demonstrated that the phase speed of oceanic equatorial Kelvin waves forced by the Madden - Julian oscillation (MJO) appears to vary substantially. Processes that are responsible for systematic changes in the phase speed of these waves are examined using an ocean general circulation model. The model was integrated for 26 yr with daily wind stress derived from the NCEP - NCAR reanalysis. The model is able to reproduce observed systematic changes of Kelvin wave phase speed reasonably well, providing a tool for the analysis of their dynamics. The relative importance of the upper ocean background state and atmospheric forcing for phase speed changes is determined based on a series of model experiments with various surface forcings. Systematic changes in phase speed are evident in all model experiments that have different slowly varying basic states, showing that variations of the upper ocean background state are not the primary cause of the changes. The model experiments that include and exclude intraseasonal components of wind stress in the eastern Pacific demonstrate that wind stress changes to the east of the date line can significantly alter the speed of Kelvin waves initially generated over the western Pacific, which often results in a phase propagation faster than the free wave speed. These faster waves contribute to the systematic changes of phase speed evident in observations. Similar results are also obtained using a linear stratified model, eliminating nonlinearity as a possible cause of the phase speed changes. C1 [Shinoda, Toshiaki; Kiladis, George N.] NOAA, Earth Syst Res Lab, Boulder, CO USA. [Shinoda, Toshiaki; Kiladis, George N.] CIRES, Climate Diagnost Ctr, Boulder, CO USA. [Roundy, Paul E.] SUNY Albany, Dept Earth & Atmospher Sci, Albany, NY 12222 USA. RP Shinoda, T (reprint author), USN, Res Lab, Stennis Space Ctr, Stennis Space Ctr, MS 39529 USA. EM toshiaki.shinoda@nrlssc.navy.mil RI Shinoda, Toshiaki/J-3745-2016 OI Shinoda, Toshiaki/0000-0003-1416-2206 NR 56 TC 27 Z9 27 U1 2 U2 7 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-3670 J9 J PHYS OCEANOGR JI J. Phys. Oceanogr. PD MAY PY 2008 VL 38 IS 5 BP 921 EP 944 DI 10.1175/2007JPO3815.1 PG 24 WC Oceanography SC Oceanography GA 302FR UT WOS:000255954700001 ER PT J AU Han, WQ Webster, PJ Lin, JL Liu, WT Fu, R Yuan, DL Hu, AX AF Han, Weiqing Webster, Peter J. Lin, Jia-Lin Liu, W. T. Fu, Rong Yuan, Dongliang Hu, Aixue TI Dynamics of intraseasonal sea level and thermocline variability in the equatorial Atlantic during 2002-03 SO JOURNAL OF PHYSICAL OCEANOGRAPHY LA English DT Article ID TROPICAL INSTABILITY WAVES; WEST-AFRICAN MONSOON; INDIAN-OCEAN; LONG WAVES; NUMERICAL-MODEL; PACIFIC-OCEAN; KELVIN WAVES; CURRENT OSCILLATIONS; SURFACE TEMPERATURE; ROSSBY WAVES AB Satellite and in situ observations in the equatorial Atlantic Ocean during 2002-03 show dominant spectral peaks at 40-60 days and secondary peaks at 10-40 days in sea level and thermocline within the intraseasonal period band (10-80 days). A detailed investigation of the dynamics of the intraseasonal variations is carried out using an ocean general circulation model, namely, the Hybrid Coordinate Ocean Model (HYCOM). Two parallel experiments are performed in the tropical Atlantic Ocean basin for the period 2000-03: one is forced by daily scatterometer winds from the Quick Scatterometer (QuikSCAT) satellite together with other forcing fields, and the other is forced by the low-passed 80-day version of the above fields. To help in understanding the role played by the wind-driven equatorial waves, a linear continuously stratified ocean model is also used. Within 3 degrees S-3 degrees N of the equatorial region, the strong 40-60-day sea surface height anomaly (SSHA) and thermocline variability result mainly from the first and second baroclinic modes equatorial Kelvin waves that are forced by intraseasonal zonal winds, with the second baroclinic mode playing a more important role. Sharp 40-50-day peaks of zonal and meridional winds appear in both the QuikSCAT and Pilot Research Moored Array in the Tropical Atlantic (PIRATA) data for the period 2002-03, and they are especially strong in 2002. Zonal wind anomaly in the central-western equatorial basin for the period 2000-06 is significantly correlated with SSHA across the equatorial basin, with simultaneous/ lag correlation ranging from-0.62 to 0.74 above 95% significance. Away from the equator (3 degrees-5 degrees N), however, sea level and thermocline variations in the 40-60-day band are caused largely by tropical instability waves (TIWs). On 10-40-day time scales and west of 10 degrees W, the spectral power of sea level and thermocline appears to be dominated by TIWs within 5 degrees S-5 degrees N of the equatorial region. The wind-driven circulation, however, also provides a significant contribution. Interestingly, east of 10 W, SSHA and thermocline variations at 10 40- day periods result almost entirely from wind-driven equatorial waves. During the boreal spring of 2002 when TIWs are weak, Kelvin waves dominate the SSHA across the equatorial basin (2 degrees S-2 degrees N). The observed quasi-biweekly Yanai waves are excited mainly by the quasi-biweekly meridional winds, and they contribute significantly to the SSHA and thermocline variations in 1 degrees-5 degrees N and 1 degrees-5 degrees S regions. C1 [Han, Weiqing] Univ Colorado, Dept Atmospher & Ocean Sci, Boulder, CO 80309 USA. [Webster, Peter J.; Liu, W. T.] Georgia Inst Technol, Sch Earth & Atmospher Sci, Atlanta, GA 30332 USA. [Lin, Jia-Lin] Ohio State Univ, Dept Geog, Columbus, OH 43210 USA. [Liu, W. T.] CALTECH, Jet Propuls Lab, Pasadena, CA 91125 USA. [Yuan, Dongliang] Chinese Acad Sci, Inst Oceanol, Qingdao, Peoples R China. [Hu, Aixue] Natl Ctr Atmospher Res, Boulder, CO 80307 USA. RP Han, WQ (reprint author), Univ Colorado, Dept Atmospher & Ocean Sci, Boulder, CO 80309 USA. EM whan@enso.colorado.edu RI Fu, Rong/B-4922-2011; Hu, Aixue/E-1063-2013 OI Hu, Aixue/0000-0002-1337-287X NR 88 TC 30 Z9 30 U1 0 U2 13 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-3670 EI 1520-0485 J9 J PHYS OCEANOGR JI J. Phys. Oceanogr. PD MAY PY 2008 VL 38 IS 5 BP 945 EP 967 DI 10.1175/2008JPO3854.1 PG 23 WC Oceanography SC Oceanography GA 302FR UT WOS:000255954700002 ER PT J AU Mulenburg, G AF Mulenburg, Gerald TI Project sponsorship: Achieving management commitment for project success SO JOURNAL OF PRODUCT INNOVATION MANAGEMENT LA English DT Book Review C1 [Mulenburg, Gerald] NASA, Washington, DC 20546 USA. RP Mulenburg, G (reprint author), NASA, Washington, DC 20546 USA. NR 2 TC 0 Z9 0 U1 0 U2 2 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0737-6782 J9 J PROD INNOVAT MANAG JI J. Prod. Innov. Manage. PD MAY PY 2008 VL 25 IS 3 BP 308 EP 310 DI 10.1111/j.1540-5885.2008.00302_3.x PG 4 WC Business; Engineering, Industrial; Management SC Business & Economics; Engineering GA 278HR UT WOS:000254276300012 ER PT J AU Holladay, JD Brooks, KP Humble, P Hu, J Simon, TM AF Holladay, J. D. Brooks, K. P. Humble, P. Hu, J. Simon, T. M. TI Compact reverse water-gas-shift reactor for extraterrestrial in situ resource utilization SO JOURNAL OF PROPULSION AND POWER LA English DT Article AB A compact reverse water-gas-shift reactor suitable for extraterrestrial use as part of the in situ propellant production system is reported. The reactor is less than 15 cm(3) in volume and weighs less than 50 g. With an Ru/ZrO2-CeO catalyst it produces over 150 g H2O/h operating at 800 degrees C. This is near equilibrium conversion at about half-scale of a Mars sample-return mission. Even at these high processing rates, the pressure drop remains low (from 1.6 to 7.6 kPa). C1 [Holladay, J. D.; Brooks, K. P.; Humble, P.; Hu, J.] Pacific NW Natl Lab, Richland, WA 99352 USA. [Simon, T. M.] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Holladay, JD (reprint author), Pacific NW Natl Lab, POB 999 MSIN K6-28, Richland, WA 99352 USA. RI Humble, Paul/K-1961-2012; Humble, Paul/E-4766-2015 OI Humble, Paul/0000-0002-2632-6557; NR 24 TC 3 Z9 3 U1 0 U2 7 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD MAY-JUN PY 2008 VL 24 IS 3 BP 578 EP 582 DI 10.2514/1.28589 PG 5 WC Engineering, Aerospace SC Engineering GA 300HN UT WOS:000255815000024 ER PT J AU Barrett, MJ Johnsont, PK AF Barrett, Michael J. Johnsont, Paul K. TI Expectations of closed-brayton-cycle heat exchangers in space power systems SO JOURNAL OF PROPULSION AND POWER LA English DT Article; Proceedings Paper CT 2nd International Energy Conversion Engineering Conference CY AUG 16-19, 2004 CL Providence, RI SP AIAA C1 [Johnsont, Paul K.] Analex Corp, Mech Syst Branch, Cleveland, OH 44135 USA. [Barrett, Michael J.] NASA, John H Glenn Res Ctr Lewis Field, Thermal Energy Convers Branch, Cleveland, OH 44135 USA. RP Barrett, MJ (reprint author), NASA, John H Glenn Res Ctr Lewis Field, Thermal Energy Convers Branch, 21000 Brookpk Rd,Mail Stop 301-2, Cleveland, OH 44135 USA. NR 15 TC 1 Z9 1 U1 0 U2 1 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD MAY-JUN PY 2008 VL 24 IS 3 BP 609 EP 613 DI 10.2514/1.26756 PG 5 WC Engineering, Aerospace SC Engineering GA 300HN UT WOS:000255815000028 ER PT J AU Zhao, TXP Yu, HB Laszlo, I Chin, M Conant, WC AF Zhao, Tom X. -P. Yu, Hongbin Laszlo, Istvan Chin, Mian Conant, William C. TI Derivation of component aerosol direct radiative forcing at the top of atmosphere for clear-sky oceans SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article DE aerosol direct radiative forcing; aerosol optical thickness ID ENERGY SYSTEM INSTRUMENT; TROPICAL INDIAN-OCEAN; GLOBAL-MODEL GOCART; ACE-ASIA; OPTICAL-PROPERTIES; SULFATE AEROSOLS; SATELLITE; CERES; CLOUDS; MODIS AB A two-step approach is proposed to derive component aerosol direct radiative forcing (ADRF) at the top of atmosphere (TOA) over global oceans from 60 degrees S to 60 degrees N for clear-sky condition by combining Terra CERES/MODIS-SSF shortwave (SW) flux and aerosol optical thickness (AOT) observations with the fractions of component AOTs from the GSFC/GOCART model. The derived global annual mean component ADRF is +0.08 +/- 0.17 W/m(2) for black carbon, -0.52 +/- 0.24 W/m(2) for organic carbon, -1.10 +/- 0.42 W/m(2) for sulfate, -0.99 +/- 0.37 W/m(2) for dust, -2.44 +/- 0.84 W/m(2) for sea salt, and -4.98 +/- 1.67 W/m(2) for total aerosols. The total ADRF has also been partitioned into anthropogenic and natural components with a value of -1.25 +/- 0.43 and -3.73 +/- 1.27 W/m(2), respectively. The major sources of error in the estimates have also been discussed. The analysis adds an alternative technique to narrow the large difference between current model-based and observation-based global estimates of component ADRF by combining the satellite measurement with the model simulation. (c) 2007 Elsevier Ltd. All rights reserved. C1 [Zhao, Tom X. -P.; Laszlo, Istvan] NOAA, NESDIS, STAR, E RA1,RM7121,WWBG,Ctr Satellite Applicat & Res, Camp Springs, MD 20746 USA. [Zhao, Tom X. -P.] UMCP, Coorporate Inst Climate Study, Earth Syst Sci Interdisciplinary Ctr, College Pk, MD 20742 USA. [Yu, Hongbin; Chin, Mian] NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. [Yu, Hongbin] UMBC, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21250 USA. [Conant, William C.] Univ Arizona, Dept Atmospher Sci, Tucson, AZ 85721 USA. RP Zhao, TXP (reprint author), NOAA, NESDIS, STAR, E RA1,RM7121,WWBG,Ctr Satellite Applicat & Res, 5200 Auth Rd, Camp Springs, MD 20746 USA. EM Xuepeng.Zhao@noaa.gov RI Yu, Hongbin/C-6485-2008; Laszlo, Istvan/F-5603-2010; Chin, Mian/J-8354-2012 OI Yu, Hongbin/0000-0003-4706-1575; Laszlo, Istvan/0000-0002-5747-9708; NR 68 TC 14 Z9 14 U1 2 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-4073 EI 1879-1352 J9 J QUANT SPECTROSC RA JI J. Quant. Spectrosc. Radiat. Transf. PD MAY PY 2008 VL 109 IS 7 BP 1162 EP 1186 DI 10.1016/j.jqsrt.2007.10.006 PG 25 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 297FY UT WOS:000255603700002 ER PT J AU Mishchenko, MI Videen, G Menguc, MP AF Mishchenko, Michael I. Videen, Gorden Menguec, M. Pinar TI The Tenth Electromagnetic and Light Scattering Conference - Preface SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Editorial Material ID NONSPHERICAL PARTICLES; SPECIAL-ISSUE; RADIATIVE-TRANSFER; INTERNATIONAL-SYMPOSIUM C1 [Mishchenko, Michael I.] NASA, Goddard Inst Space Studies, New York, NY 10025 USA. [Videen, Gorden] USA, Res Lab, AMSRD ARL CI EM, Adelphi, MD 20783 USA. [Menguec, M. Pinar] Univ Kentucky, Dept Mech Engn, Lexington, KY 40506 USA. RP Mishchenko, MI (reprint author), NASA, Goddard Inst Space Studies, 2880 Broadway, New York, NY 10025 USA. EM crmim@giss.nasa.gov RI Menguc, Pinar/O-3114-2013; Mishchenko, Michael/D-4426-2012 NR 12 TC 8 Z9 8 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-4073 J9 J QUANT SPECTROSC RA JI J. Quant. Spectrosc. Radiat. Transf. PD MAY PY 2008 VL 109 IS 8 BP 1335 EP 1337 DI 10.1016/j.jqsrt.2008.01.015 PG 3 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 296TZ UT WOS:000255570000001 ER PT J AU Mishchenko, MI Videen, G Khlebtsov, NG Wriedt, T Zakharova, NT AF Mishchenko, Michael I. Videen, Gorden Khlebtsov, Nikolai G. Wriedt, Thomas Zakharova, Nadia T. TI Comprehensive T-matrix reference database: A 2006-07 update SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article; Proceedings Paper CT 10th International Conference on Electromagnetic and Light Scattering by Non-Spherical Particles CY JUN 17-23, 2007 CL Bodrum, TURKEY DE electromagnetic scattering; T-matrix method ID ANOMALOUS DIFFRACTION APPROXIMATION; SCATTERING CROSS-SECTION; RANDOM PARTICULATE MEDIA; LIGHT-SCATTERING; NONSPHERICAL PARTICLES; MULTIPLE-SCATTERING; SATELLITE-OBSERVATIONS; RADIATIVE PROPERTIES; OPTICAL-PROPERTIES; COHERENT BACKSCATTERING AB This paper presents an update to the comprehensive database of T-matrix publications authored by us previously and mostly includes the publications that appeared since 2005. It also lists several earlier publications not included in the original database. (C) 2008 Elsevier Ltd. All rights reserved. C1 [Mishchenko, Michael I.; Zakharova, Nadia T.] NASA, Goddard Inst Space Studies, New York, NY 10025 USA. [Videen, Gorden] USA, Res Lab, AMSRL IS EE, Adelphi, MD 20783 USA. [Khlebtsov, Nikolai G.] Russian Acad Sci, Inst Biochem & Physiol Plants & Microorganisms, Saratov 410015, Russia. [Wriedt, Thomas] Inst Werkstofftech, D-28359 Bremen, Germany. RP Mishchenko, MI (reprint author), NASA, Goddard Inst Space Studies, 2880 Broadway, New York, NY 10025 USA. EM crmim@giss.nasa.gov RI Mishchenko, Michael/D-4426-2012; Khlebtsov, Nikolai/D-6199-2017; Pylaev, Timofey/A-8401-2016; OI Pylaev, Timofey/0000-0002-2701-3333; Khlebtsov, Nikolai/0000-0002-2055-7784 NR 127 TC 36 Z9 38 U1 0 U2 13 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-4073 EI 1879-1352 J9 J QUANT SPECTROSC RA JI J. Quant. Spectrosc. Radiat. Transf. PD MAY PY 2008 VL 109 IS 8 BP 1447 EP 1460 DI 10.1016/j.jqsrt.2008.01.001 PG 14 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 296TZ UT WOS:000255570000012 ER PT J AU Hada, M Georgakilas, AG AF Hada, Megumi Georgakilas, Alexandros G. TI Formation of clustered DNA damage after high-LET irradiation: A review SO JOURNAL OF RADIATION RESEARCH LA English DT Review DE clustered DNA damage; high-LET radiations ID DOUBLE-STRAND BREAKS; BASE-EXCISION-REPAIR; HUMAN APURINIC/APYRIMIDINIC ENDONUCLEASE; BISTRANDED ABASIC SITES; AVERAGE LENGTH ANALYSIS; MONTE-CARLO-SIMULATION; HEAT-LABILE SITES; IONIZING-RADIATION; ESCHERICHIA-COLI; MAMMALIAN-CELLS AB Radiation can cause as well as cure cancer. The risk of developing radiation-induced cancer has traditionally been estimated from cancer incidence among survivors of the atomic bombs in Hiroshima and Nagasaki.(1)) These data provide the best estimate of human cancer risk over the dose range for low linear energy transfer (LET) radiations, such as X- or gamma-rays. The situation of estimating the real biological effects becomes even more difficult in the case of high LET particles encountered in space or as the result of domestic exposure to alpha-particles from radon gas emitters or other radioactive emitters like uranium-238. Complex DNA damage, i.e., the signature of high-LET radiations comprises of closely spaced DNA lesions forming a cluster of DNA damage. The two basic groups of complex DNA damage are double strand breaks (DSBs) and non-DSB oxidative clustered DNA lesions (OCDL). Theoretical analysis and experimental evidence suggest an increased complexity and severity of complex DNA damage with increasing LET (linear energy transfer) and a high mutagenic or carcinogenic potential. Data available on the formation of clustered DNA damage (DSBs and OCDL) by high-LET radiations are often controversial suggesting a variable response to dose and type of radiation. The chemical nature and cellular repair mechanisms of complex DNA damage have been much less characterized than those of isolated DNA lesions like an oxidized base or a single strand break especially in the case of high-LET radiation. This review will focus on the induction of clustered DNA damage by high-LET radiations presenting the earlier and recent relative data. C1 [Georgakilas, Alexandros G.] E Carolina Univ, Thomas Harriot Coll Arts & Sci, Dept Biol, Greenville, NC 27858 USA. [Hada, Megumi] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. [Hada, Megumi] Univ Space Res Assoc, Houston, TX 77058 USA. RP Georgakilas, AG (reprint author), E Carolina Univ, Thomas Harriot Coll Arts & Sci, Dept Biol, Greenville, NC 27858 USA. EM georgakilasa@ecu.edu NR 79 TC 186 Z9 195 U1 7 U2 39 PU JAPAN RADIATION RESEARCH SOC PI CHIBA PA C/O NAT INST RADIOLOGICAL SCI 9-1 ANAGAWA-4-CHOME INAGE-KU, CHIBA, 263, JAPAN SN 0449-3060 J9 J RADIAT RES JI J. Radiat. Res. PD MAY PY 2008 VL 49 IS 3 BP 203 EP 210 DI 10.1269/jrr.07123 PG 8 WC Biology; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Radiology, Nuclear Medicine & Medical Imaging GA 330FG UT WOS:000257924600001 PM 18413977 ER PT J AU Hollis, BR Collier, AS AF Hollis, Brian R. Collier, Arnold S. TI Turbulent aeroheating testing of Mars Science Laboratory entry vehicle SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article; Proceedings Paper CT AIAA 45th Aerospace Sciences Meeting and Exhibit CY JAN 08-11, 2007 CL Reno, NV SP Amer Inst Aeronaut & Astronaut ID CAVITIES; SCHEMES AB An experimental investigation of turbulent aeroheating on the Mars Science Laboratory entry vehicle heat shield has been conducted in the Arnold Engineering Development Center Hypervelocity Wind Tunnel No. 9. Testing was performed on a 6 in. (0.1524 m) diameter Mars Science Laboratory model in perfect-gas N-2 in the tunnel's Mach 8 and Mach 10 nozzles at freestream Reynolds numbers of 4.1 x 10(6)-49 X 10(6) ft (1.3 x 10(7)-16 x 10(7) m) and 1.2 x 10(6)-19 X 10(6) ft (0.39 x 10(7)-62 x 10(7) m), respectively. These conditions were sufficient to span the regime of boundary-layer flow from completely laminar to fully developed turbulent flow over the entire forebody. A supporting aeroheating test was also conducted in the Langley Research Center 20 Inch Mach 6 Air Tunnel at freestream Reynolds numbers of 1 x 10(6)-7 x 10(6) ft (0.36 x 10(7)-2.2 x 10(7) m) to help corroborate the Tunnel 9 results. A complementary computational fluid dynamics study was conducted in parallel to the wind-tunnel testing. Laminar and turbulent predictions were generated for the wind-tunnel test conditions and comparisons were performed with the data for the purpose of helping to define uncertainty margins on predictions for aeroheating environments during entry into the Martian atmosphere. Data from both wind-tunnel tests and comparisons with the predictions are presented herein. It was concluded from these comparisons that for perfect-gas conditions, the computational tools could predict fully laminar or fully turbulent heating conditions to within +/- 12% or better of the experimental data. C1 [Hollis, Brian R.] NASA, Langley Res Ctr, Aerothermodynam Branch, Hampton, VA 23681 USA. [Collier, Arnold S.] Arnold Engn Dev Ctr, Silver Spring, MD 20901 USA. RP Hollis, BR (reprint author), NASA, Langley Res Ctr, Aerothermodynam Branch, Hampton, VA 23681 USA. NR 19 TC 9 Z9 9 U1 1 U2 1 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0022-4650 J9 J SPACECRAFT ROCKETS JI J. Spacecr. Rockets PD MAY-JUN PY 2008 VL 45 IS 3 BP 417 EP 427 DI 10.2514/1.31798 PG 11 WC Engineering, Aerospace SC Engineering GA 312SG UT WOS:000256690500001 ER PT J AU Davis, MC White, JT AF Davis, Mark C. White, J. Terry TI X-43A flight-test-determined aerodynamic force and moment characteristics at Mach 7.0 SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article; Proceedings Paper CT AIAA/AHI 14th International Space Planes and Hypersonic Systems and Technologies Conference CY NOV 06-09, 2006 CL Canberra, AUSTRALIA SP Amer Inst Aeronaut & Astronaut, AHI ID SPACE-SHUTTLE ORBITER AB The second flight of the Hyper-X program afforded a unique opportunity to determine the aerodynamic force and moment characteristics of an airframe-integrated scramjet-powered aircraft in hypersonic flight. These data were gathered via a repeated series of pitch, yaw, and roll doublets, frequency sweeps, and pushover-pullup maneuvers performed throughout the X-43A cowl-closed descent. Maneuvers were conducted at Mach numbers of 6.80-0.95 and at altitudes from 92,000 ft mean sea level to sea level. The dynamic pressure varied from 1300 to 400 psf with the angle of attack ranging from 0 to 14 deg. The flight-extracted aerodynamics were compared with preflight predictions based on wind-tunnel test data. The X-43A flight-derived axial force was found to be 10-15% higher than prediction. Underpredictions of similar magnitude were observed for the normal force. For Mach numbers above 4.0, the flight-derived stability and control characteristics resulted in larger-than-predicted static margins, with the largest discrepancy approximately 5 in. forward along the x-axis center of gravity at Mach 6.0. This condition would result in less static margin in pitch. The predicted lateral-directional stability and control characteristics matched well with flight data when allowance was made for the high uncertainty in angle of sideslip. C1 [Davis, Mark C.; White, J. Terry] NASA, Dryden Flight Res Ctr, Edwards AFB, CA 93523 USA. RP Davis, MC (reprint author), NASA, Dryden Flight Res Ctr, POB 273,Mail Stop 2228, Edwards AFB, CA 93523 USA. NR 12 TC 4 Z9 7 U1 1 U2 9 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0022-4650 J9 J SPACECRAFT ROCKETS JI J. Spacecr. Rockets PD MAY-JUN PY 2008 VL 45 IS 3 BP 472 EP 484 DI 10.2514/1.30413 PG 13 WC Engineering, Aerospace SC Engineering GA 312SG UT WOS:000256690500007 ER PT J AU Lightsey, EG Mogensen, AE Burkhart, PD Ely, TA Duncan, C AF Lightsey, E. Glenn Mogensen, Andreas E. Burkhart, P. Daniel Ely, Todd A. Duncan, Courtney TI Real-time navigation for Mars missions using the Mars Network SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article ID EXPLORATION; FILTER AB A NASA Mars technology program task is developing a prototype, embedded, real-time navigation system for Mars final approach and entry, descent, and landing using the Mars Network's Electra ultrahigh frequency transceiver. The Mars Network is ideally situated to provide spacecraft-to-spacecraft navigation via the Electra ultrahigh frequency transceiver, which is a versatile telecommunications payload that is capable of providing autonomous on-orbit, real-time trajectory determination using two-way Doppler measurements between a Mars approach vehicle and a Mars Network orbiter. A set of analyses based on the 2010 encounter at Mars between the Mars Science Laboratory and the Mars Reconnaissance Orbiter demonstrate that the navigation system is capable of achieving a 300 m or better atmosphere entry knowledge error and that the resulting technology is a key component to enabling pinpoint landing. The development approach, software design, and test results from an engineering development unit are presented. C1 [Lightsey, E. Glenn; Mogensen, Andreas E.] Univ Texas Austin, Dept Aerosp Engn & Engn Mech, Austin, TX 78712 USA. [Burkhart, P. Daniel; Ely, Todd A.; Duncan, Courtney] CALTECH, Jet Prop Lab, Guidance Navigat & Control Sect, Pasadena, CA 91109 USA. RP Lightsey, EG (reprint author), Univ Texas Austin, Dept Aerosp Engn & Engn Mech, 1 Univ Stn,C0600, Austin, TX 78712 USA. NR 21 TC 20 Z9 24 U1 1 U2 6 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0022-4650 J9 J SPACECRAFT ROCKETS JI J. Spacecr. Rockets PD MAY-JUN PY 2008 VL 45 IS 3 BP 519 EP 533 DI 10.2514/1.30974 PG 15 WC Engineering, Aerospace SC Engineering GA 312SG UT WOS:000256690500012 ER PT J AU Kornfeld, RP Garcia, MD Craig, LE Butman, S Signori, GM AF Kornfeld, Richard P. Garcia, Mark D. Craig, Lynn E. Butman, Stan Signori, Gina M. TI Entry, descent, and landing communications for the 2007 Phoenix Mars Lander SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article AB This paper addresses NASA's requirement on the 2007 Phoenix Mars Lander to provide spacecraft communications during entry, descent, and landing on Mars to allow the identification of probable root cause should any mission failure occur. The Phoenix mission launched on 4 August 2007 and will land on 25 May 2008 on the northern plains of Mars to conduct a three-month study of the Martian environment. The paper discusses the architectural trades in designing a communications link and surveys the entry, descent, and landing communications approaches taken by previous missions. It then discusses the Phoenix-specific constraints and degrees of freedoms and presents a novel and robust implementation approach to entry, descent, and landing communications. The overall methodology and conclusions described herein can serve as a pathfinder for the entry, descent, and landing communications architecture and implementation of future Mars landed missions. C1 [Kornfeld, Richard P.] CALTECH, Jet Prop Lab, Syst Engn Sect, Pasadena, CA 91109 USA. [Garcia, Mark D.; Craig, Lynn E.] CALTECH, Jet Prop Lab, Guidance Nav & Control Sect, Pasadena, CA 91109 USA. [Butman, Stan] CALTECH, Jet Prop Lab, Flight Commun Syst Sect, Pasadena, CA 91109 USA. [Signori, Gina M.] Deep Space Commun, Denver, CO 80210 USA. RP Kornfeld, RP (reprint author), CALTECH, Jet Prop Lab, Syst Engn Sect, Mail Stop 264-623,4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 8 TC 5 Z9 8 U1 0 U2 1 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0022-4650 J9 J SPACECRAFT ROCKETS JI J. Spacecr. Rockets PD MAY-JUN PY 2008 VL 45 IS 3 BP 534 EP 547 DI 10.2514/1.33789 PG 14 WC Engineering, Aerospace SC Engineering GA 312SG UT WOS:000256690500013 ER PT J AU Gasch, M Johnson, S Marschall, J AF Gasch, Matthew Johnson, Sylvia Marschall, Jochen TI Thermal conductivity characterization of hafnium diboride-based ultra-high-temperature ceramics SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article; Proceedings Paper CT Workshop on Ultra-High-Temperature Ceramic Materials CY JUL 23-25, 2007 CL Menlo Pk, CA SP AFOSR ID TRANSITION METAL CARBIDES; SOLID-STATE PROPERTIES; ZIRCONIUM DIBORIDE; GRAIN-BOUNDARIES; TITANIUM CARBIDE; RESISTANCE; MONOCRYSTALLINE; MICROSTRUCTURE; MICROCRACKING; DIFFUSIVITY AB We evaluated the thermal conductivity of HfB2-based ultra-high-temperature ceramics from laser flash diffusivity measurements in the 25 degrees-600 degrees C temperature range. Commercially available powders were used to prepare HfB2 composites containing 20 vol% SiC, some including TaSi2 (5 vol%) and Ir (0.5 or 2 vol%) additions. Samples were consolidated via conventional hot pressing or spark plasma sintering. Processing differences were shown to lead to differences in magnitude and temperature dependence of effective thermal conductivity. We compared results with measured values from heritage materials and analyzed trends using a network model of effective thermal conductivity, incorporating the effects of porosity, grain size, Kapitza resistance, and individual constituent thermal conductivities. C1 [Marschall, Jochen] SRI Int, Mol Phys Lab, Menlo Pk, CA 94025 USA. [Gasch, Matthew; Johnson, Sylvia] NASA, Ames Res Ctr, Thermal Protect Mat & Syst Branch, Moffett Field, CA 94035 USA. RP Marschall, J (reprint author), SRI Int, Mol Phys Lab, 333 Ravenswood Ave, Menlo Pk, CA 94025 USA. EM jochen.marschall@sri.com NR 58 TC 25 Z9 25 U1 2 U2 22 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD MAY PY 2008 VL 91 IS 5 BP 1423 EP 1432 DI 10.1111/j.1551-2916.2008.02364.x PG 10 WC Materials Science, Ceramics SC Materials Science GA 297ZR UT WOS:000255656400007 ER PT J AU Eldridge, JI Spuckler, CM AF Eldridge, Jeffrey I. Spuckler, Charles M. TI Determination of scattering and absorption coefficients for plasma-sprayed yttria-stabilized zirconia thermal barrier coatings SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID REFRACTIVE-INDEX; CUBIC ZIRCONIA; RADIATIVE BEHAVIOR; HIGH-TEMPERATURES; WAVELENGTH; EMITTANCE; LAYER AB Prediction of radiative transport through translucent thermal barrier coatings (TBCs) can only be performed if the scattering and absorption coefficients and index of refraction of the TBC are known. To date, very limited information on these coefficients, which depend on both the coating composition and the microstructure, has been available for the very commonly utilized plasma-sprayed 8 wt% yttria-stabilized zirconia (8YSZ) TBCs. In this work, the scattering and absorption coefficients of freestanding plasma-sprayed 8YSZ coatings were determined from room-temperature normal-incidence directional-hemispherical reflectance and transmittance spectra over the wavelength range from 0.8 to 7.5 mu m. Spectra were collected over a wide range of coating thickness from 60 to almost 900 mu m. From the reflectance and transmittance spectra, the scattering and absorption coefficients as a function of wavelength were obtained by fitting the reflectance and transmittance values predicted by a four flux model to the experimentally measured values at all measured 8YSZ thicknesses. While the combined effects of absorption and scattering were shown in general to exhibit a nonexponential dependence of transmittance on specimen thickness, it was shown that for sufficiently high absorption and optical thickness, an exponential dependence becomes a good approximation. In addition, the implications of the wavelength dependence of the plasma-sprayed 8YSZ scattering and absorption coefficients on (1) obtaining accurate surface-temperature pyrometer measurements and on (2) applying mid-infrared reflectance to monitor TBC delamination are discussed. C1 [Eldridge, Jeffrey I.; Spuckler, Charles M.] NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Eldridge, JI (reprint author), NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. EM jeffrey.i.eldridge@nasa.gov NR 27 TC 38 Z9 39 U1 1 U2 22 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD MAY PY 2008 VL 91 IS 5 BP 1603 EP 1611 DI 10.1111/j.1551-2916.2008.02349.x PG 9 WC Materials Science, Ceramics SC Materials Science GA 297ZR UT WOS:000255656400034 ER PT J AU Mortley, DG Bonsi, CK Hill, WA Morris, CE Williams, CS Davis, CF Williams, JW Levine, LH Petersen, BV Wheeler, RM AF Mortley, Desmond G. Bonsi, Conrad K. Hill, Walter A. Morris, Carlton E. Williams, Carol S. Davis, Ceyla F. Williams, John W. Levine, Lanfang H. Petersen, Barbara V. Wheeler, Raymond M. TI Influence of microgravity environment on root growth, soluble sugars, and starch concentration of sweetpotato stem cuttings SO JOURNAL OF THE AMERICAN SOCIETY FOR HORTICULTURAL SCIENCE LA English DT Article DE hypoxia; Ipomea batata; Phytagel; carbohydrate metabolism; bioregenerative life support ID ELECTRON MICROSCOPY; BRASSICA-RAPA; LEAF EPINASTY; METABOLISM; WEIGHTLESSNESS; CARBOHYDRATE; SPACEFLIGHT; ETHYLENE; SHOOTS; LEAVES AB Because sweetpotato [Ipomoea batatas (L.) Lam.] stem cuttings regenerate very easily and quickly, a study of their early growth and development in microgravity could be useful to an understanding of morphological changes that might occur under such conditions for crops that are propagated vegetatively. An experiment was conducted aboard a U.S. Space Shuttle to investigate the impact of microgravity on root growth, distribution of amyloplasts in the root cells, and on the concentration of soluble sugars and starch in the stems of sweetpotatoes. Twelve stem cuttings of 'Whatley/Loretan' sweetpotato (5 cm long) with three to four nodes were grown in each of two plant growth units filled with a nutrient agarose medium impregnated with a half-strength Hoagland solution. One plant growth unit was flown on Space Shuttle Colombia for 5 days, whereas the other remained on the ground as a control. The cuttings were received within 2 h postflight and, along with ground controls, processed in approximate to 45 min. Adventitious roots were counted, measured, and fixed for electron microscopy and stems frozen for starch and sugar assays. Air samples were collected from the headspace of each plant growth unit for postflight determination of carbon dioxide, oxygen, and ethylene levels. All stem cuttings produced adventitious roots and growth was quite vigorous in both ground-based and flight samples and, except for a slight browning of some root tips in the flight samples, all stem cuttings appeared normal. The roots on the flight cuttings tended to grow in random directions. Also, stem cuttings grown in microgravity had more roots and greater total root length than ground-based controls. Amyloplasts in root cap cells of ground-based controls were evenly sedimented toward one end compared with a more random distribution in the flight samples. The concentration of soluble sugars, glucose, fructose, and sucrose and total starch concentration were all substantially greater in the stems of flight samples than those found in the ground-based samples. Carbon dioxide levels were 50% greater and oxygen marginally lower in the flight plants, whereas ethylene levels were similar and averaged less than 10 nL.L-1. Despite the greater accumulation of carbohydrates in the stems, and greater root growth in the flight cuttings, overall results showed minimal differences in cell development between space flight and ground-based tissues. This suggests that the space flight environment did not adversely impact sweetpotato metabolism and that vegetative cuttings should be an acceptable approach for propagating sweetpotato plants for space applications. C1 [Mortley, Desmond G.; Bonsi, Conrad K.; Hill, Walter A.; Morris, Carlton E.] Tuskegee Univ, Ctr Food & Environm Syst Human Explorat Space, Tuskegee, AL 36088 USA. [Mortley, Desmond G.; Bonsi, Conrad K.; Hill, Walter A.; Morris, Carlton E.] Tuskegee Univ, GW Carver Agr Expt Stn, Tuskegee, AL 36088 USA. [Williams, Carol S.; Davis, Ceyla F.; Williams, John W.] Tuskegee Univ, Biomed Res Ctr, RCMI, Tuskegee, AL 36088 USA. [Levine, Lanfang H.] Dynam Corp, Kennedy Space Ctr, FL 32899 USA. [Petersen, Barbara V.] ASRC Aerosp, Kennedy Space Ctr, FL 32899 USA. [Wheeler, Raymond M.] NASA, Bio Sci Off, Kennedy Space Ctr, FL 32899 USA. RP Mortley, DG (reprint author), Tuskegee Univ, Ctr Food & Environm Syst Human Explorat Space, 214 Milbank Hall, Tuskegee, AL 36088 USA. EM mortleyd@tuskegee.edu FU NCRR NIH HHS [G12 RR003059-20S1, G12 RR003059] NR 37 TC 9 Z9 11 U1 0 U2 6 PU AMER SOC HORTICULTURAL SCIENCE PI ALEXANDRIA PA 113 S WEST ST, STE 200, ALEXANDRIA, VA 22314-2851 USA SN 0003-1062 J9 J AM SOC HORTIC SCI JI J. Am. Soc. Hortic. Sci. PD MAY PY 2008 VL 133 IS 3 BP 327 EP 332 PG 6 WC Horticulture SC Agriculture GA 306HR UT WOS:000256239400003 PM 20186286 ER PT J AU Oye, MM Bank, SR Ptak, AJ Reedy, RC Goorsky, MS Holmes, AL AF Oye, Michael M. Bank, Seth R. Ptak, Aaron J. Reedy, Robert C. Goorsky, Mark S. Holmes, Archie L., Jr. TI Role of ion damage on unintentional Ca incorporation during the plasma-assisted molecular-beam epitaxy growth of dilute nitrides using N(2)/Ar source gas mixtures SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article ID RETARDING-FIELD ANALYZER; DEPLETION-WIDTH GAINNAS; RF PLASMA; SOLAR-CELLS; ENERGY; TEMPERATURE; QUALITY; GAASN; INGAASN; GANAS AB Unintentional Ca incorporation caused by Ca-contaminated substrate surfaces on as-purchased GaAs wafers are known to limit the efficiency of solar cells based on dilute nitride materials. This article focuses on further understanding the conditions and mechanisms by which these Ca impurities incorporate. Plasma-assisted molecular-beam epitaxy utilizing a 1% N(2) in Ar precursor gas mixture was used to grow GaAs at 400 and 580 degrees C, and GaN(0.01)As(0.99) at 400 degrees C. Two plasma operating combinations of rf power and gas flow rate were used to generate different amounts and energies of both ions and other plasma species, while keeping nitrogen incorporation constant. The ions were characterized with a dual-grid, retarding-field ion energy analyzer, and the corresponding ion energy distributions are presented to correlate ions with Ca incorporation. When appropriate, dc-biased deflector plates were used to remove ions during growth. Secondary ion mass spectrometry was used to measure Ca in GaAs and GaN(0.01)As(0.99). Ca incorporation was observed in the dilute nitride samples, but the effects of ions did not exceed other Ca incorporation mechanisms associated with defects due to both low temperature growth and nitrogen incorporation; however, different neutral active nitrogen species (atomic N and metastable N(2)(*)) may be a factor. Ca incorporation measured in GaAs grown at 400 degrees C with a pure Ar plasma is predominantly due to defects associated with low temperature growth, as opposed to plasma damage caused by the ions. GaAs growths at 580 degrees C without a plasma did not exhibit Ca incorporation, but growth at 580 degrees C with ions from a pure Ar plasma caused Ca incorporation. (C) 2008 American Vacuum Society. C1 [Oye, Michael M.; Goorsky, Mark S.] Univ Calif Los Angeles, Dept Mat Sci & Engn, Los Angeles, CA 90095 USA. [Bank, Seth R.] Univ Texas Austin, Dept Elect & Comp Engn, Austin, TX 78712 USA. [Ptak, Aaron J.; Reedy, Robert C.] Natl Renewable Energy Lab, Golden, CO 80401 USA. [Holmes, Archie L., Jr.] Univ Virginia, Dept Elect & Comp Engn, Charlottesville, VA 22904 USA. RP Oye, MM (reprint author), NASA, Ames Res Ctr, M-S 229-1 Moffett Field, Moffett Field, CA 94035 USA. EM moye@arc.nasa.gov NR 37 TC 2 Z9 2 U1 2 U2 6 PU A V S AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD MAY PY 2008 VL 26 IS 3 BP 1058 EP 1063 DI 10.1116/1.2924329 PG 6 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 307FO UT WOS:000256304600030 ER PT J AU Brown, ME Pinzon, JE Prince, SD AF Brown, Molly E. Pinzon, Jorge E. Prince, Stephen D. TI Using satellite remote sensing data in a spatially explicit price model: Vegetation dynamics and millet prices SO LAND ECONOMICS LA English DT Article ID WEST AFRICAN SAHEL; CROP PRODUCTION; HILBERT SPECTRUM; SOIL-MANAGEMENT; TIME-SERIES; NOAA-AVHRR; CLIMATE; INDEX; DEVALUATION; SENEGAL AB Famine early warning organizations use data from multiple disciplines to assess food insecurity of communities and regions in less-developed parts of the world. Here we present a model that integrates information on the suitability of the growing season and millet prices in the dry central and northern areas of West Africa. The model is used to create spatially continuous maps of millet prices. By coupling the model with remote sensing vegetation data estimated one to four months into the future, we create a leading indicator of potential price movements for early warning of food crises. C1 [Brown, Molly E.; Pinzon, Jorge E.] SSAI NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Prince, Stephen D.] Univ Maryland, Dept Geog, College Pk, MD 20742 USA. RP Brown, ME (reprint author), SSAI NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RI Brown, Molly/E-2724-2010 OI Brown, Molly/0000-0001-7384-3314 NR 58 TC 6 Z9 6 U1 1 U2 6 PU UNIV WISCONSIN PI MADISON PA SOCIAL SCIENCE BLDG, MADISON, WI 53706 USA SN 0023-7639 J9 LAND ECON JI Land Econ. PD MAY PY 2008 VL 84 IS 2 BP 340 EP 357 PG 18 WC Economics; Environmental Studies SC Business & Economics; Environmental Sciences & Ecology GA 303NU UT WOS:000256048000010 ER PT J AU Kuhn, SD Sridharan, K Hao, Z Muir, P Suresh, M Singh, A Raj, SV AF Kuhn, S. D. Sridharan, K. Hao, Z. Muir, P. Suresh, M. Singh, A. Raj, S. V. TI Biocompatibility of uncoated and diamond-like carbon coated Ti-20%Hf alloy SO MATERIALS SCIENCE AND TECHNOLOGY LA English DT Article DE biocompatibility; diamond like carbon; flow cytometer; orthopaedic; Ti-Hf ID COBALT-CHROMIUM-ALLOY; IN-VITRO; COATINGS; TITANIUM; TOXICITY AB Biocompatibilities of uncoated and diamond like carbon (DLC) coated Ti-20%Hf alloy have been investigated by means of 3T3 mouse fibroblast cell viability quantification using flow cytometry. For comparison, similar tests were performed for pure Ti, Hf, and V as well as a commercial orthopaedic alloy, Ti-6Al-4V. Under the test conditions used, the biocompatibilities of uncoated and DLC coated Ti-20% Hf alloy, pure Hf, and Ti-6Al-4V alloy were comparable to that of pure Ti, a metal known for its superior biocompatibility, while pure V clearly exhibited the lowest biocompatibility of all the materials that were evaluated. The addition of Hf to Ti resulted in significant solid solution strengthening and at 20% Hf concentration the hardness of this alloy was comparable to that of the Ti-6Al-4V alloy. Ti-Hf alloys and wear resistant, low friction DLC coatings may either be used in conjunction with or may independently hold promise for orthopaedic implants and possibly other biomedical applications. C1 [Kuhn, S. D.; Sridharan, K.] Univ Wisconsin, Coll Engn, Madison, WI 53706 USA. [Hao, Z.; Muir, P.] Univ Wisconsin, Sch Vet Med, Comparat Orthopaed Res Lab, Madison, WI 53706 USA. [Raj, S. V.] NASA, Cleveland, OH USA. RP Sridharan, K (reprint author), Univ Wisconsin, Coll Engn, Madison, WI 53706 USA. EM kumar@engr.wisc.edu NR 21 TC 0 Z9 1 U1 2 U2 10 PU MANEY PUBLISHING PI LEEDS PA STE 1C, JOSEPHS WELL, HANOVER WALK, LEEDS LS3 1AB, W YORKS, ENGLAND SN 0267-0836 J9 MATER SCI TECH-LOND JI Mater. Sci. Technol. PD MAY PY 2008 VL 24 IS 5 BP 575 EP 578 DI 10.1179/174328408X281903 PG 4 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 319CF UT WOS:000257140000009 ER PT J AU Diaz, FJ Macias, MH Hagan, DR Najera, M Montano, JG Guerrero, H Tovar, A Sanchez, M Moreno, A Moreno, MF Garcia, MR Melchor, MT AF Diaz, Francisco J. Macias, Maciste H. Hagan, Donald R. Najera, Magdalena Montano, Jose G. Guerrero, Humberto Tovar, Antonio Sanchez, Marco Moreno, Agustin Moreno, Maria F. Garcia, Maria R. Melchor, Maria T. TI Metabolic and fitness alterations in subjects with Down's Syndrome SO MEDICINE AND SCIENCE IN SPORTS AND EXERCISE LA English DT Meeting Abstract C1 [Diaz, Francisco J.; Macias, Maciste H.; Najera, Magdalena; Montano, Jose G.; Guerrero, Humberto; Tovar, Antonio; Sanchez, Marco; Moreno, Agustin; Moreno, Maria F.; Garcia, Maria R.; Melchor, Maria T.] Univ Guanajuato, Leon, Mexico. [Hagan, Donald R.] NASA, Houston, TX USA. EM msanchez@webtelmex.net.mx NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0195-9131 J9 MED SCI SPORT EXER JI Med. Sci. Sports Exerc. PD MAY PY 2008 VL 40 IS 5 SU S BP S291 EP S291 PG 1 WC Sport Sciences SC Sport Sciences GA V19KI UT WOS:000208070902490 ER PT J AU Everett, ME DeWitt, J Lee, S Laughlin, M Wilson, C Loehr, J AF Everett, Meghan E. DeWitt, John Lee, Stuart Laughlin, Mitzi Wilson, Cassie Loehr, Jim TI Joint Angles at Heel Strike and Toe Off during Motorized and Non-Motorized Treadmill Locomotion SO MEDICINE AND SCIENCE IN SPORTS AND EXERCISE LA English DT Meeting Abstract C1 [Everett, Meghan E.; DeWitt, John; Lee, Stuart; Laughlin, Mitzi; Wilson, Cassie; Loehr, Jim] NASA JSC, Houston, TX USA. EM meghan.e.everett@nasa.gov NR 0 TC 0 Z9 0 U1 1 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0195-9131 J9 MED SCI SPORT EXER JI Med. Sci. Sports Exerc. PD MAY PY 2008 VL 40 IS 5 SU S BP S302 EP S303 DI 10.1249/01.mss.0000323635.31107.b3 PG 2 WC Sport Sciences SC Sport Sciences GA V19KI UT WOS:000208070902535 ER PT J AU Lee, SMC Loehr, JA English, KL Sibonga, J Maddocks, MJ Smith, SA Hagan, RD AF Lee, Stuart M. C. Loehr, James A. English, Kirk L. Sibonga, Jean Maddocks, Mary Jane Smith, Scott A. Hagan, R. Donald TI Bone Mineral Density Adaptations of the Hip and Spine to Training with the Advanced Resistive Exercise Device and with Free Weights in Ambulatory Subjects SO MEDICINE AND SCIENCE IN SPORTS AND EXERCISE LA English DT Meeting Abstract C1 [Lee, Stuart M. C.; Loehr, James A.; Maddocks, Mary Jane; Smith, Scott A.] Wyle Labs, Houston, TX USA. [English, Kirk L.] JES Tech, Houston, TX USA. [Sibonga, Jean] Univ Space Res Associates, Houston, TX USA. [Hagan, R. Donald] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. EM stuart.lee-1@nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0195-9131 J9 MED SCI SPORT EXER JI Med. Sci. Sports Exerc. PD MAY PY 2008 VL 40 IS 5 SU S BP S303 EP S303 DI 10.1249/01.mss.0000323636.08236.de PG 1 WC Sport Sciences SC Sport Sciences GA V19KI UT WOS:000208070902536 ER PT J AU Lewis, KM Liang, MTC Spalding, TW Bassin, SL Tawney, JD Arnaud, SB AF Lewis, Kevin M. Liang, Michael T. C. Spalding, Thomas W. Bassin, Stan L. Tawney, James D. Arnaud, Sara B. TI Bone Bending Stiffness And Mineral Density In Endurance Cyclists, Runners And Untrained Men SO MEDICINE AND SCIENCE IN SPORTS AND EXERCISE LA English DT Meeting Abstract C1 [Lewis, Kevin M.; Liang, Michael T. C.; Spalding, Thomas W.; Tawney, James D.] Calif State Polytech Univ Pomona, Pomona, CA 91768 USA. [Bassin, Stan L.] Univ Calif Irvine, Irvine, CA USA. [Arnaud, Sara B.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0195-9131 J9 MED SCI SPORT EXER JI Med. Sci. Sports Exerc. PD MAY PY 2008 VL 40 IS 5 SU S BP S40 EP S40 DI 10.1249/01.mss.0000321619.18532.da PG 1 WC Sport Sciences SC Sport Sciences GA V19KI UT WOS:000208070901153 ER PT J AU Moore, AD Lee, SMC Wilson, CA Stenger, MB Platts, SH AF Moore, Alan D., Jr. Lee, Stuart M. C. Wilson, Cassie A. Stenger, Michael B. Platts, Steven H. TI Artificial Gravity Prevents Loss of Peak Oxygen Uptake During 21 Days of Bed Rest SO MEDICINE AND SCIENCE IN SPORTS AND EXERCISE LA English DT Meeting Abstract C1 [Moore, Alan D., Jr.; Lee, Stuart M. C.; Stenger, Michael B.] NASA JSC, Wyle Labs, Houston, TX USA. [Wilson, Cassie A.] NASA JSC, JES Tech, Houston, TX USA. EM alan.d.moore@nasa.gov NR 0 TC 1 Z9 1 U1 1 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0195-9131 J9 MED SCI SPORT EXER JI Med. Sci. Sports Exerc. PD MAY PY 2008 VL 40 IS 5 SU S BP S302 EP S302 DI 10.1249/01.mss.0000323633.23483.b0 PG 1 WC Sport Sciences SC Sport Sciences GA V19KI UT WOS:000208070902533 ER PT J AU Wier, LT Suminski, RR Poston, WS Randles, AM Arenare, B Jackson, AS AF Wier, Larry T. Suminski, Richard R. Poston, Walker S. Randles, Anthony M. Arenare, Brian Jackson, Andrew S. TI The Effect of Habitual Smoking on VO2max SO MEDICINE AND SCIENCE IN SPORTS AND EXERCISE LA English DT Meeting Abstract C1 [Wier, Larry T.] NASA JSC, Wyle Labs, Houston, TX USA. [Suminski, Richard R.] Kansas City Univ Med & Biosci, Kansas City, MO USA. [Poston, Walker S.; Randles, Anthony M.] Univ Missouri, Kansas City Sch Med, Kansas City, MO 64110 USA. [Arenare, Brian] Kelsey Seybold, Houston, TX USA. [Jackson, Andrew S.] Univ Houston, Houston, TX USA. EM larry.t.wier@nasa.gov NR 0 TC 0 Z9 0 U1 1 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0195-9131 J9 MED SCI SPORT EXER JI Med. Sci. Sports Exerc. PD MAY PY 2008 VL 40 IS 5 SU S BP S197 EP S197 DI 10.1249/01.mss.0000322310.86814.95 PG 1 WC Sport Sciences SC Sport Sciences GA V19KI UT WOS:000208070902113 ER PT J AU Tou, JC Foley, A Yuan, YV Arnaud, S Wade, CE Brown, M AF Tou, Janet C. Foley, Andrea Yuan, Yvonne V. Arnaud, Sara Wade, Charles E. Brown, Marybeth TI The effect of ovariectomy combined with hindlimb unloading and reloading on the long bones of mature Sprague-Dawley rats SO MENOPAUSE-THE JOURNAL OF THE NORTH AMERICAN MENOPAUSE SOCIETY LA English DT Article DE estrogen; mechanical unloading; tibia; femur; bone biomechanics ID FEMALE RATS; PHYSICAL-ACTIVITY; BED REST; POSTMENOPAUSAL WOMEN; CANCELLOUS BONE; BODY-WEIGHT; EXERCISE; SUSPENSION; MODEL; MASS AB Objective: To determine the effect of loss of ovarian function and mechanical loading (ie, inactivity) alone or in combination on bone mass and strength. Design: Mature (aged 6 mo) rats were ovariectomized to induce loss of ovarian function and bone. Hindlimb unloading (HLU) was used to determine the effect of mechanical unloading and reloading on bone mass and strength. Bone mass of the femur and tibia was determined using dual-energy x-ray absorptiometry. Femoral and tibial bone strength was determined by a three-point bending test and by a torsion test. Results: Ovariectomy (OVX) alone decreased total bone mineral density (BMD) in the femur (-5.5%, P = 0.03) and tibia (-7.3%, P = 0.01) compared with that for sham-operated animals. HLU alone for 4 weeks had no significant effect on bone. Together OVX/HLU accentuated BMD loss in the femur (-10. 5%, P < 0.0 1) compared with that for sham-operated animals. The femur was more sensitive than the tibia to the combination of OVX/HLU, indicated by the reduction (-5.3%, P < 0.05) of total BMD below that achieved by OVX alone. Torsion tests showed that OVX/HLU but not OVX or HLU alone reduced bone strength. There was a correlation between lower femoral total BMD (r(2) = 0.65, P < 0.001) and reduced torque strength. Bone loss did not continue during the 2 weeks of reloading. Conclusions: OVX accompanied by mechanical unloading results in more rapid and severe bone loss than either OVX or unloading alone and therefore is associated with a greater likelihood of osteoporosis. C1 [Tou, Janet C.] W Virginia Univ, Div Anim & Nutr Sci, Morgantown, WV 26506 USA. [Brown, Marybeth] Univ Missouri, Dept Phys Therapy, Columbia, MO USA. [Brown, Marybeth] Univ Missouri, Ctr Gender Physiol, Columbia, MO USA. [Yuan, Yvonne V.] Ryerson Univ, Sch Nutr, Toronto, ON, Canada. [Arnaud, Sara] NASA, Ames Res Ctr, Div Life Sci, Moffett Field, CA 94035 USA. [Wade, Charles E.] USA, Inst Surg Res, Houston, TX USA. RP Tou, JC (reprint author), W Virginia Univ, Div Anim & Nutr Sci, Morgantown, WV 26506 USA. EM janet.tou@mail.wvu.edu FU NIA NIH HHS [AG15796] NR 36 TC 13 Z9 15 U1 0 U2 2 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 1072-3714 J9 MENOPAUSE JI Menopause-J. N. Am. Menopause Soc. PD MAY-JUN PY 2008 VL 15 IS 3 BP 494 EP 502 DI 10.1097/gme.0b013e318148bbad PG 9 WC Obstetrics & Gynecology SC Obstetrics & Gynecology GA 298MU UT WOS:000255692600017 PM 18030174 ER PT J AU Weissman, PR Hicks, MD Abell, PA Choi, YJ Lowry, SC AF Weissman, Paul R. Hicks, Michael D. Abell, Paul A. Choi, Young-Jun Lowry, Stephen C. TI Rosetta target asteroid 2867 Steins: An unusual E-type asteroid SO METEORITICS & PLANETARY SCIENCE LA English DT Article ID NEAR-EARTH ASTEROIDS; SPECTROSCOPIC SURVEY; 2867-STEINS; METEORITES; TELESCOPE; HUNGARIA; MISSION; OBJECTS; IRON AB ESA's Rosetta spacecraft will fly by main-belt asteroid 2867 Steins on September 5, 2008. We obtained new visible wavelength spectra of 2867 Steins on December 19, 2006 (UT), using the Palomar 5 in telescope and the facility Double Spectrograph. Two sets of spectra, taken similar to 3 h apart, one half of the rotation period for 2867 Steins, show It to be an E-type asteroid. The asteroid displays a 0.50 mu m feature that is considered diagnostic of the E(II) sub-class, but is deeper than any previously observed E-type. This feature Is most likely due to the presence of oldhamite (CaS) on the asteroid's surface. Also, the observed Steins spectra are far redder than any other known E-types. There is potential evidence for heterogeneity on hemispheric scales, one side of the asteroid appearing to be significantly redder than the other. No known recovered meteorite sample matches the Unusual spectra of 2867 Steins, but the closest analog would be similar to an enstatite achondrite (aubrite). C1 [Weissman, Paul R.; Hicks, Michael D.; Choi, Young-Jun] CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA. [Abell, Paul A.] Planetary Sci Inst, Tucson, AZ 85719 USA. [Abell, Paul A.] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. [Lowry, Stephen C.] Queens Univ Belfast, Astrophys Res Ctr, Dept Phys & Astron, Belfast BT7 1NN, Antrim, North Ireland. RP Weissman, PR (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,Mail Stop 183-301, Pasadena, CA 91125 USA. EM paul.r.weissman@jpl.nasa.gov FU NASA; Leverhulme Trust FX This work was supported in part by the NASA Planetary Astronomy Program. It was performed in part at the Jet Propulsion Laboratory under a contract with NASA. YJC thanks the NASA Post-doctoral Program for support. SCL thanks the Leverhulme Trust for support. We thank the staff at Palomar Observatory for their help in conducting these observations. We thank Rick Binzel for providing the spreadsheet for performing the principal component analysis and the PCA values from Bus and Binzel (2002a). We thank the referees, Torn Burbine and Beth Clark, for helpful comments on an earlier draft of this paper. NR 38 TC 9 Z9 9 U1 0 U2 1 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 1086-9379 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD MAY PY 2008 VL 43 IS 5 BP 905 EP 914 PG 10 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 357QH UT WOS:000259860700006 ER PT J AU Carballido, A Stone, JM Turner, NJ AF Carballido, Augusto Stone, James M. Turner, Neal J. TI Kinematics of solid particles in a turbulent protoplanetary disc SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE accretion, accretion discs; MHD; turbulence; Solar system : formation; planetary systems : protoplanetary discs ID T-TAURI DISKS; STREAMING INSTABILITY; SOLAR NEBULA; ACCRETION; EVOLUTION; BODIES; GAS; VELOCITIES; REGIONS; DRIVEN AB We perform numerical simulations of solid particle motion in a shearing box model of a protoplanetary disc. The accretion flow is turbulent due to the action of the magnetorotational instability. Aerodynamic drag on the particles is modelled using the Epstein law with the gas velocity interpolated to the particle position. The effect of the magnetohydrodynamic turbulence on particle velocity dispersions is quantified for solids of different stopping times t(s), or equivalently, different sizes. The anisotropy of the turbulence is reflected upon the dispersions of the particle velocity components, with the radial component larger than both the azimuthal and vertical components for particles larger than similar to 10 cm (assuming minimum-mass solar nebula conditions at 5 au). The dispersion of the particle velocity magnitude, as well as that of the radial and azimuthal components, as functions of stopping time, agrees with previous analytical results for isotropic turbulence. The relative speed between pairs of particles with the same value of t(s) decays faster with decreasing separation than in the case of solids with different stopping time. Correlations in the particle number density introduce a non-uniform spatial distribution of solids in the 10 to 100 cm size range. Any clump of particles is disrupted by the turbulence in less than one tenth of an orbital period, and the maximally concentrated clumps are stable against self-gravitational collapse. C1 [Carballido, Augusto; Turner, Neal J.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Stone, James M.] Princeton Univ, Dept Astrophys Sci, Princeton, NJ 08544 USA. RP Carballido, A (reprint author), CALTECH, Jet Prop Lab, MS 169-506, Pasadena, CA 91109 USA. EM augusto@jpl.nasa.gov; jstone@astro.princeton.edu; neal.turner@jpl.nasa.gov OI Turner, Neal/0000-0001-8292-1943 NR 30 TC 18 Z9 18 U1 0 U2 1 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD MAY 1 PY 2008 VL 386 IS 1 BP 145 EP 154 DI 10.1111/j.1365-2966.2008.13014.x PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 290SM UT WOS:000255142500034 ER PT J AU Ghosh, KK Mapelli, M AF Ghosh, Kajal K. Mapelli, Michela TI UGC 7069: the largest ring galaxy SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE methods : N-body simulations; galaxies : individual : UGC 7069; galaxies : interactions; galaxies : nuclei; galaxies : peculiar; galaxies : starburst ID DWARF SEYFERT NUCLEI; STAR-FORMATION RATES; RADIO-SOURCES; SKY SURVEY; EMISSION; SEARCH; MODELS AB We find that UGC 7069 is the largest ring galaxy known to date. In this Letter, we present a multiwavelength study of this galaxy ( combining radio, Two- Micron All-Sky Survey, optical and ultraviolet data). The ring of UGC 7069, whose diameter measures similar to 115 kpc, is also warped at its edges. The nucleus appears double-peaked and hosts a possible LINER. The ultraviolet data indicate a strong blue colour and suggest that UGC 7069 is a starburst galaxy. We also present N-body simulation results, which indicate that galaxy collisions can produce such huge rings. Large inclination angles between the target and the intruder galaxy may account for the formation of warped rings. Multiwavelength observations are highly essential to constrain our simulation results, which will address the formation and evolution of such a rare galaxy. C1 [Ghosh, Kajal K.] USRA, NASA, NSSTC, MSFC, Huntsville, AL 35805 USA. [Mapelli, Michela] Univ Zurich, Inst Theoret Phys, CH-8057 Zurich, Switzerland. RP Ghosh, KK (reprint author), USRA, NASA, NSSTC, MSFC, 320 Sparkman Dr, Huntsville, AL 35805 USA. EM kajal.k.ghosh@nasa.gov; mapelli@physik.unizh.ch OI Mapelli, Michela/0000-0001-8799-2548 NR 35 TC 8 Z9 9 U1 0 U2 0 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD MAY 1 PY 2008 VL 386 IS 1 BP L38 EP L42 DI 10.1111/j.1745-3933.2008.00456.x PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 290SM UT WOS:000255142500009 ER PT J AU Smith, RJ Marzke, RO Hornschemeier, AE Bridges, TJ Hudson, MJ Miller, NA Lucey, JR Vazquez, GA Carter, D AF Smith, Russell J. Marzke, Ronald O. Hornschemeier, Ann E. Bridges, Terry J. Hudson, Michael J. Miller, Neal A. Lucey, John R. Vazquez, Gerardo A. Carter, David TI Large population of recently quenched red-sequence dwarf galaxies in the outskirts of the Coma cluster SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE galaxies : clusters : individual : Coma; galaxies : dwarf ID ENVIRONMENTAL DEPENDENCE; STELLAR POPULATIONS; STAR-FORMATION AB We analyse the stellar populations of 75 red- sequence dwarf galaxies in the Coma cluster, based on high signal- to- noise ratio spectroscopy from the 6.5- m MMT. The sample covers a luminosity range 3 - 4 mag below M*, in the cluster core and in a field centred 1 degrees to the south-west. We find a strong dependence of the absorption-line strengths with location in the cluster. Galaxies further from the cluster centre have stronger Balmer lines than inner-field galaxies of the same luminosity. The magnesium lines are weaker at large radius, while the iron lines are not correlated with radius. Converting the line strengths into estimates of stellar age, metallicity and abundance ratios, we find the gradients are driven by variations in age (> 6 sigma significance) and in the iron abundance Fe/ H (similar to 2.7 sigma significance). The light element ( Mg, C, N, Ca) abundances are almost independent of radius. At radius of 0 degrees.4 - 1 degrees.3 (similar to 0.3 - 1.0 times the virial radius), dwarf galaxies have ages similar to 3.8 Gyr on average, compared to similar to 6 Gyr near the cluster centre. The outer dwarfs are also similar to 50 per cent more iron-enriched, at given luminosity. Our results confirm earlier indications that the ages of red- sequence galaxies depend on location within clusters, and in Coma in particular. The very strong trends found here suggest that dwarf galaxies are especially susceptible to environmental 'quenching', and/or that the south-west part of Coma is particularly a clear example of recent quenching in an infalling subcluster. C1 [Smith, Russell J.; Lucey, John R.] Univ Durham, Dept Phys, Durham DH1 3LE, England. [Marzke, Ronald O.] San Francisco State Univ, Dept Phys & Astron, San Francisco, CA 94132 USA. [Hornschemeier, Ann E.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Bridges, Terry J.] Queens Univ, Dept Phys, Kingston, ON K7L 3N6, Canada. [Hudson, Michael J.] Univ Waterloo, Dept Phys & Astron, Waterloo, ON N2L 3G1, Canada. [Miller, Neal A.; Vazquez, Gerardo A.] Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. [Vazquez, Gerardo A.] Salisbury Univ, Dept Phys, Salisbury, MD 21801 USA. [Carter, David] Liverpool John Moores Univ, Astrophys Res Inst, Birkenhead CH41 1LD, Merseyside, England. RP Smith, RJ (reprint author), Univ Durham, Dept Phys, Durham DH1 3LE, England. EM russell.smith@durham.ac.uk RI Hudson, Michael/H-3238-2012 OI Hudson, Michael/0000-0002-1437-3786 NR 15 TC 35 Z9 35 U1 0 U2 0 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD MAY 1 PY 2008 VL 386 IS 1 BP L96 EP L100 DI 10.1111/j.1745-3933.2008.00469.x PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 290SM UT WOS:000255142500021 ER PT J AU Tokay, A Bashor, PG Habib, E Kasparis, T AF Tokay, Ali Bashor, Paul G. Habib, Emad Kasparis, Takis TI Raindrop size distribution measurements in tropical cyclones SO MONTHLY WEATHER REVIEW LA English DT Article ID RAINFALL MEASUREMENTS; DROP; WSR-88D; DISDROMETER; STRATIFORM; MESOSCALE; SPECTRA; CLOUDS; RADARS; FLOOD AB Characteristics of the raindrop size distribution in seven tropical cyclones have been studied through impact-type disdrometer measurements at three different sites during the 2004-06 Atlantic hurricane seasons. One of the cyclones has been observed at two different sites. High concentrations of small and/or midsize drops were observed in the presence or absence of large drops. Even in the presence of large drops, the maximum drop diameter rarely exceeded 4 mm. These characteristics of raindrop size distribution were observed in all stages of tropical cyclones, unless the storm was in the extratropical stage where the tropical cyclone and a midlatitude frontal system had merged. The presence of relatively high concentrations of large drops in extratropical cyclones resembled the size distribution in continental thunderstorms. The integral rain parameters of drop concentration, liquid water content, and rain rate at fixed reflectivity were therefore lower in extratropical cyclones than in tropical cyclones. In tropical cyclones, at a disdrometer-calculated reflectivity of 40 dBZ, the number concentration was 700 +/- 100 drops m(-3), while the liquid water content and rain rate were 0.90 +/- 0.05 g m(-3) and 18.5 +/- 0.5 mm h(-1), respectively. The mean mass diameter, on the other hand, was 1.67 +/- 0.3 mm. The comparison of raindrop size distributions between Atlantic tropical cyclones and storms that occurred in the central tropical Pacific island of Roi-Namur revealed that the number density is slightly shifted toward smaller drops, resulting in higher-integral rain parameters and lower mean mass and maximum drop diameters at the latter site. Considering parameterization of the raindrop size distribution in tropical cyclones, characteristics of the normalized gamma distribution parameters were examined with respect to reflectivity. The mean mass diameter increased rapidly with reflectivity, while the normalized intercept parameter had an increasing trend with reflectivity. The shape parameter, on the other hand, decreased in a reflectivity range from 10 to 20 dBZ and remained steady at higher reflectivities. Considering the repeatability of the characteristics of the raindrop size distribution, a second impact disdrometer that was located 5.3 km away from the primary site in Wallops Island, Virginia, had similar size spectra in selected tropical cyclones. C1 [Tokay, Ali] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Tokay, Ali] Univ Maryland Baltimore Cty, Joint Ctr Earth Syst Technol, Baltimore, MD 21228 USA. [Bashor, Paul G.] NASA, Wallops Flight Facil, Comp Sci Corp, Wallops Isl, VA USA. [Habib, Emad] Univ Louisiana Lafayette, Dept Civil Engn, Lafayette, LA 70504 USA. [Habib, Emad] Univ Louisiana Lafayette, Ctr Louisiana Water Studies, Lafayette, LA 70504 USA. [Kasparis, Takis] Univ Cent Florida, Sch Elect Engn & Comp Sci, Orlando, FL 32816 USA. RP Tokay, A (reprint author), NASA, Goddard Space Flight Ctr, Code 613-1, Greenbelt, MD 20771 USA. EM tokay@radar.gsfc.nasa.gov NR 32 TC 32 Z9 36 U1 1 U2 4 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PD MAY PY 2008 VL 136 IS 5 BP 1669 EP 1685 DI 10.1175/2007MWR2122.1 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 302NI UT WOS:000255974700007 ER PT J AU Worden, HM Bowman, KW Worden, JR Eldering, A Beer, R AF Worden, Helen M. Bowman, Kevin W. Worden, John R. Eldering, Annmarie Beer, Reinhard TI Satellite measurements of the clear-sky greenhouse effect from tropospheric ozone SO NATURE GEOSCIENCE LA English DT Article ID EMISSION SPECTROMETER; LOWER STRATOSPHERE; AURA MISSION; RETRIEVALS; SYSTEM; MODEL; TES AB Radiative forcing from anthropogenic ozone in the troposphere is an important factor in climate change(1), with an average value of 0.35 W m(-2) according to the Intergovernmental Panel for Climate Change(1) (IPCC). IPCC model results range from 0.25 to 0.65 W m(-2), owing to uncertainties in the estimates of pre-industrial concentrations of tropospheric ozone(1-3), and in the present spatial and temporal distributions of tropospheric ozone(4-8), which are much more variable than those of longer-lived greenhouse gases such as carbon dioxide. Here, we analyse spectrally resolved measurements of infrared radiance from the Tropospheric Emission Spectrometer(9) on board the NASA Aura satellite, as well as corresponding estimates of atmospheric ozone and water vapour, to obtain the reduction in clear-sky outgoing long-wave radiation due to ozone in the upper troposphere over the oceans. Accounting for sea surface temperature, we calculate an average reduction in clear-sky outgoing long-wave radiation for the year 2006 of 0.48 +/- 0.14 W m(-2) between 45 degrees S and 45 degrees N. This estimate of the clear-sky greenhouse effect from tropospheric ozone provides a critical observational constraint for ozone radiative forcing used in climate model predictions. C1 [Worden, Helen M.; Bowman, Kevin W.; Worden, John R.; Eldering, Annmarie; Beer, Reinhard] CALTECH, Jet Prop Lab, Div Sci, Pasadena, CA 91109 USA. RP Worden, HM (reprint author), Natl Ctr Atmospher Res, Div Atmospher Chem, POB 3000, Boulder, CO 80307 USA. EM hmw@ucar.edu; Kevin.Bowman@jpl.nasa.gov NR 30 TC 36 Z9 36 U1 1 U2 8 PU NATURE PUBLISHING GROUP PI NEW YORK PA 75 VARICK ST, 9TH FLR, NEW YORK, NY 10013-1917 USA SN 1752-0894 EI 1752-0908 J9 NAT GEOSCI JI Nat. Geosci. PD MAY PY 2008 VL 1 IS 5 BP 305 EP 308 DI 10.1038/ngeo182 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 309BB UT WOS:000256433600012 ER PT J AU Righter, K Humayun, M Danielson, L AF Righter, K. Humayun, M. Danielson, L. TI Partitioning of palladium at high pressures and temperatures during core formation SO NATURE GEOSCIENCE LA English DT Article ID SIDEROPHILE ELEMENTS; SILICATE MELTS; OXYGEN FUGACITY; UPPER-MANTLE; EARTH; CONSTRAINTS; SOLUBILITY; PLATINUM; NICKEL; DIFFERENTIATION AB An early equilibration of the Earth's mantle with the metals that later formed the core may explain the concentrations of iron-loving (siderophile) elements in the mantle. However, a subset of these elements, the highly siderophile elements including palladium, are present in greater concentrations than expected. Moreover, their relative ratios are similar to those found in chondrites, that is, primitive solar-system materials(1-4). On the basis of very high partition coefficients for these elements derived from experiments at low pressures and temperatures (for example, a coefficient for palladium > 10(4)), it has been argued that the high mantle concentrations of the highly siderophile elements and also of volatile elements originated from the addition of chondritic material after core formation as a 'late veneer'(1-4). Here we present experiments at higher pressures and temperatures that approximate the conditions of early Earth, and find much lower partition coefficients for palladium, about 480, consistent with an equilibration scenario. This obviates the need for a late veneer to explain the terrestrial-mantle palladium content, and calls into question traditional explanations for the origin of the Earth's volatile elements. C1 [Righter, K.; Danielson, L.] NASA, Lyndon B Johnson Space Ctr, Mailcode KT, Houston, TX 77058 USA. [Humayun, M.] Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32310 USA. [Humayun, M.] Florida State Univ, Dept Geol Sci, Tallahassee, FL 32310 USA. RP Righter, K (reprint author), NASA, Lyndon B Johnson Space Ctr, Mailcode KT, 2101 NASA Pkwy, Houston, TX 77058 USA. EM kevin.righter-1@nasa.gov OI Humayun, Munir/0000-0001-8516-9435 NR 25 TC 50 Z9 51 U1 0 U2 18 PU NATURE PUBLISHING GROUP PI NEW YORK PA 75 VARICK STREET, 9TH FLOOR, NEW YORK, NY 10013-1917 USA SN 1752-0894 J9 NAT GEOSCI JI Nat. Geosci. PD MAY PY 2008 VL 1 IS 5 BP 321 EP 323 DI 10.1038/ngeo180 PG 3 WC Geosciences, Multidisciplinary SC Geology GA 309BB UT WOS:000256433600016 ER PT J AU Jassemnejad, B Bohannan, A Lekki, J Weiland, K AF Jassemnejad, Baha Bohannan, April Lekki, John Weiland, Ken TI Mode sorter and detector based on photon orbital angular momentum SO OPTICAL ENGINEERING LA English DT Article DE mode sorter; orbital angular momentum; photon; Laguerre-Gaussian modes ID GAUSSIAN LASER MODES; LIGHT AB Photons were generated possessing orbital angular momentum (OAM) in the form of Laguerre- Gaussian (LG) laser modes. Three Mach-Zehnder interferometer systems, with the use of Dove prisms, were constructed to sort and detect the LG modes based on their OAM state. Successful generating, sorting, and detecting of LG modes is the first step towards information encoding and decoding via lasers. It is possible to generate many LG modes, which can be orthogonally decoded. With many modes to encode information with it is possible to transfer more than one bit of information with a single photon using LG encoding. An experimental test of this concept was performed by demonstrating the generation and sorting of LG modes with attenuated intensities averaging below one photon passing through the system at a time. In summary, generating, sorting, and low-power detecting of specific LG modes were all demonstrated. (c) 2008 Society of Photo-Optical Instrumentation Engineers. C1 [Jassemnejad, Baha; Bohannan, April] Univ Cent Oklahoma, Dept Engn & Phys, Edmond, OK 73034 USA. [Lekki, John; Weiland, Ken] NASA Glenn Res Ctr, Instrumentat & Controls Div, Cleveland, OH 44135 USA. RP Jassemnejad, B (reprint author), Univ Cent Oklahoma, Dept Engn & Phys, 100 N Univ Dr, Edmond, OK 73034 USA. NR 11 TC 3 Z9 3 U1 0 U2 3 PU SPIE-SOC PHOTO-OPTICAL INSTRUMENTATION ENGINEERS PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98225 USA SN 0091-3286 J9 OPT ENG JI Opt. Eng. PD MAY PY 2008 VL 47 IS 5 AR 053001 DI 10.1117/1.2931686 PG 5 WC Optics SC Optics GA 320IO UT WOS:000257227100005 ER PT J AU Bhatia, AK AF Bhatia, A. K. TI Applications of the hybrid theory to the scattering of electrons from He(+) and Li(2+) and resonances in these systems SO PHYSICAL REVIEW A LA English DT Article ID ACCURATE CALCULATION; ATOMIC HYDROGEN; PHASE-SHIFTS; AUTOIONIZATION; COLLISIONS; IONS AB The hybrid theory of electron-hydrogen elastic scattering [Phys. Rev. A 75, 032713 (2007)] is applied to the S-wave scattering of electrons from He(+) and Li(2+). In this method, both short-range and long-range correlations are included in the Schrodinger equation at the same time. Phase shifts obtained in this calculation have rigorous lower bounds to the exact phase shifts and they are compared with those obtained using the Feshbach projection operator formalism [Phys. Rev. A 66, 064702 (2002)], the close-coupling approach [J. Phys. B 2, 44 (1969)], and the Harris-Nesbet method [J. Phys. B 35, 4475 (2002); J. Phys. B 36, 2291 (2003)]. The agreement among all the calculations is very good. These systems have doubly excited or Feshbach resonances embedded in the continuum. The resonance parameters for the lowest (1)S resonances in He and Li(+) are calculated and they are compared with the results obtained using the Feshbach projection operator formalism [Phys. Rev. A 11, 2018 (1975); Phys. Rev. A 15, 131 (1977)]. It is concluded that accurate resonance parameters can be obtained by the present method, which has the advantage of including corrections due to neighboring resonances and the continuum in which these resonances are embedded. C1 NASA, Goddard Space Flight Ctr, Heliophys Sci Div, Greenbelt, MD 20771 USA. RP Bhatia, AK (reprint author), NASA, Goddard Space Flight Ctr, Heliophys Sci Div, Greenbelt, MD 20771 USA. NR 15 TC 2 Z9 2 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 2008 VL 77 IS 5 AR 052707 DI 10.1103/PhysRevA.77.052707 PN A PG 5 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 317MI UT WOS:000257023900084 ER PT J AU Lee, GW Gangopadhyay, AK Hyers, RW Rathz, TJ Rogers, JR Robinson, DS Goldman, AI Kelton, KF AF Lee, G. W. Gangopadhyay, A. K. Hyers, R. W. Rathz, T. J. Rogers, J. R. Robinson, D. S. Goldman, A. I. Kelton, K. F. TI Local structure of equilibrium and supercooled Ti-Zr-Ni liquids SO PHYSICAL REVIEW B LA English DT Article ID SHORT-RANGE ORDER; LENNARD-JONES CLUSTERS; MOLECULAR-DYNAMICS; NEUTRON-SCATTERING; UNDERCOOLED MELTS; METALLIC GLASSES; X-RAY; TRANSITION; EVOLUTION; MAGNETISM AB Recently, we reported the results of experimental in situ high-energy x-ray diffraction studies of electrostatically levitated equilibrium and supercooled metallic elements and alloy liquids, showing evidence for icosahedral short-range ordering (ISRO). In this paper, these studies are extended to binary Ti-Zr and ternary Ti-Zr-Ni alloys. From a cluster-based analysis of the x-ray structure factors, it is concluded that ISRO in the binary alloys becomes progressively more dominant, and the coherence length of the order becomes longer, with the addition of Ni, especially near the concentration of 21 at. % Ni. The effect of chemical interactions among Ti/Zr-Ni and the atomic size on the stabilization of the ISRO is discussed. C1 [Lee, G. W.; Gangopadhyay, A. K.; Kelton, K. F.] Washington Univ, Dept Phys, St Louis, MO 63130 USA. [Lee, G. W.] Korea Res Inst Stand & Sci, Taejon 305340, Choongnam, South Korea. [Hyers, R. W.] Univ Massachusetts, Amherst, MA 01003 USA. [Rathz, T. J.] Univ Alabama, Huntsville, AL 35801 USA. [Rogers, J. R.] NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. [Robinson, D. S.; Goldman, A. I.] US DOE, Ames Lab, Ames, IA 50011 USA. [Robinson, D. S.; Goldman, A. I.] Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP Lee, GW (reprint author), Washington Univ, Dept Phys, St Louis, MO 63130 USA. RI Hyers, Robert/G-3755-2010 NR 53 TC 33 Z9 33 U1 2 U2 21 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAY PY 2008 VL 77 IS 18 AR 184102 DI 10.1103/PhysRevB.77.184102 PG 8 WC Physics, Condensed Matter SC Physics GA 315MY UT WOS:000256885300027 ER PT J AU McEnery, J Ritz, S Gehrels, N AF McEnery, Julie Ritz, Steve Gehrels, Nell TI GLAST goes for blast-off SO PHYSICS WORLD LA English DT Article C1 [McEnery, Julie; Ritz, Steve; Gehrels, Nell] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP McEnery, J (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM julie.mcenery@nasa.gov RI Gehrels, Neil/D-2971-2012; McEnery, Julie/D-6612-2012 NR 0 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0953-8585 J9 PHYS WORLD JI Phys. World PD MAY PY 2008 VL 21 IS 5 BP 31 EP 33 PG 3 WC Physics, Multidisciplinary SC Physics GA 297MY UT WOS:000255622000033 ER PT J AU Mouginot, J Kofman, W Safaeinilli, A Herique, A AF Mouginot, J. Kofman, W. Safaeinilli, A. Herique, A. TI Correction of the ionospheric distortion on the MARSIS surface sounding echoes SO PLANETARY AND SPACE SCIENCE LA English DT Article DE mars; ionosphere; MARSIS; ionospheric dispersion compensation; total electron content ID ELECTRON-DENSITY PROFILES; RADIO SCIENCE; GLOBAL SURVEYOR; NEUTRAL ATMOSPHERE; MARTIAN IONOSPHERE; RADAR SOUNDINGS AB Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) on the Mars Express (MEX) spacecraft has made numerous measurements of the Martian surface and subsurface. However, all of these measurements are distorted by the ionosphere and must be compensated before any analysis. We have developed a technique to compensate for the ionospheric distortions. This technique provides a powerful tool to derive the total electron content (TEC) and other higher-order terms of the limited expansion of the plasma dispersion function that are related to overall shape of the electron column profile. The derived parameters are fitted by using a Chapman model to derive ionospheric parameters like no, electron density primary peak (maximum for solar zenith angle (SZA) equal 0), and the neutral height scale H. Our estimated ionospheric parameters are in good agreement with Mars Global Surveyor (MGS) radio-occultation data. However, since MARSIS does not have the observation geometry limitations of the radio occultation measurements, our derived parameters extend over a large range of SZA for each MEX orbit. The first results from our technique have been discussed by Safacinili et al. C1 [Mouginot, J.; Kofman, W.; Herique, A.] CNRS UJF, Lab Planetol Grenoble, F-38041 Grenoble, France. [Safaeinilli, A.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Mouginot, J (reprint author), CNRS UJF, Lab Planetol Grenoble, F-38041 Grenoble, France. EM jeremie.mouginot@obs.ujf-grenoble.fr RI Kofman, Wlodek/C-4556-2008; Mouginot, Jeremie/G-7045-2015; Herique, Alain/E-7210-2017 OI Herique, Alain/0000-0003-3699-883X NR 23 TC 27 Z9 27 U1 0 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0032-0633 J9 PLANET SPACE SCI JI Planet Space Sci. PD MAY PY 2008 VL 56 IS 7 BP 917 EP 926 DI 10.1016/j.pss.2008.01.010 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 314RS UT WOS:000256827100006 ER PT J AU Dohm, JM Anderson, RC Barlow, NG Miyamoto, H Davies, AG Taylor, GJ Baker, VR Boynton, WV Keller, J Kerry, K Janes, D Fairen, AG Schulze-Makuch, D Glamoclija, M Marinangeli, L Ori, GG Strom, RG Williams, JP Ferris, JC Rodriguez, JAP de Pablo, MA Karunatillake, S AF Dohm, James M. Anderson, Robert C. Barlow, Nadine G. Miyamoto, Hirdy Davies, Ashley G. Taylor, G. Jeffrey Baker, Victor R. Boynton, William V. Keller, John Kerry, Kris Janes, Daniel Fairen, Alberto G. Schulze-Makuch, Dirk Glamoclija, Mihaela Marinangeli, Lucia Ori, Gian G. Strom, Robert G. Williams, Jean-Pierre Ferris, Justin C. Rodriguez, J. A. P. de Pablo, Miguel A. Karunatillake, Suniti TI Recent geological and hydrological activity on Mars: The Tharsis/Elysiurn corridor SO PLANETARY AND SPACE SCIENCE LA English DT Review DE Mars; magmatism; tectonism; hydrothermal activity; present Mars; life ID PATHFINDER LANDING SITE; MARTIAN NORTHERN PLAINS; MERIDIANI-PLANUM; THARSIS REGION; MAGMATIC EVOLUTION; OMEGA/MARS EXPRESS; THERMAL EVOLUTION; CERBERUS FOSSAE; CHEMICAL-COMPOSITION; TERRESTRIAL PLANETS AB The paradigm of an ancient warm, wet, and dynamically active Mars, which transitioned into a cold, dry, and internally dead planet, has persisted up until recently despite published Viking-based geologic maps that indicate geologic and hydrologic activity extending into the Late Amazonian epoch. This paradigm is shifting to a water-enriched planet, which may still exhibit internal activity, based on a collection of geologic, hydrologic, topographic, chemical, and elemental evidences obtained by the Viking, Mars Global Surveyor (MGS), Mars Odyssey (MO), Mars Exploration Rovers (MER), and Mars Express (MEx) missions. The evidence includes: (1) strati graphically young rock materials such as pristine lava flows with few, if any, superposed impact craters; (2) tectonic features that cut stratigraphically young materials; (3) features with possible aqueous origin such as structurally controlled channels that dissect stratigraphically young materials and anastomosing-patterned slope streaks on hillslopes; (4) spatially varying elemental abundances for such elements as hydrogen (H) and chlorine (Cl) recorded in rock materials up to 0.33 m depth; and (5) regions of elevated atmospheric methane. This evidence is pronounced in parts of Tharsis, Elysium, and the region that straddles the two volcanic provinces, collectively referred to here as the Tharsis/Elysium corridor. Based in part on field investigations of Solfatara Crater, Italy, recommended as a suitable terrestrial analog, the Tharsis/Elysium corridor should be considered a prime target for Mars Reconnaissance Orbiter (MRO) investigations and future science-driven exploration to investigate whether Mars is internally and hydrologically active at the present time, and whether the persistence of this activity has resulted in biologic activity. (c) 2008 Elsevier Ltd. All rights reserved. C1 [Dohm, James M.; Baker, Victor R.] Univ Arizona, Dept Hydrol & Water Resources, Tucson, AZ 85721 USA. [Dohm, James M.; Baker, Victor R.; Boynton, William V.; Keller, John; Kerry, Kris; Janes, Daniel; Strom, Robert G.] Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. [Williams, Jean-Pierre] CALTECH, Jet Prop Lab, Div Geol & Planetary Sci, Pasadena, CA 91109 USA. [Barlow, Nadine G.] No Arizona Univ, Dept Phys & Astron, Flagstaff, AZ 86011 USA. [Miyamoto, Hirdy] Univ Tokyo, Dept Geosyst Engn, Tokyo 1138654, Japan. [Taylor, G. Jeffrey] Univ Hawaii, Hawaii Inst Geophys & Planetol, Honolulu, HI 96822 USA. [Fairen, Alberto G.] Univ Autonoma Madrid, Ctr Biol Mol, CSIC, E-28049 Madrid, Spain. [Fairen, Alberto G.] NASA, Ames Res Ctr, Sapce Sci & Astrobiol Div, Moffett Field, CA 94035 USA. [Schulze-Makuch, Dirk] Washington State Univ, Sch Earth & Environm Sci, Pullman, WA 99164 USA. [Glamoclija, Mihaela; Marinangeli, Lucia; Ori, Gian G.] Univ G DAnnunzio, IRSPS, Pescara, Italy. [Ferris, Justin C.] NOAA, W Coast & Alaska Tsunami Warning Ctr, Palmer, AK 99645 USA. [Rodriguez, J. A. P.] Univ Tokyo, Dept Earth & Planetary Sci, Bunkyo Ku, Tokyo 1130033, Japan. [de Pablo, Miguel A.] Univ Alcala de Henares, Dept Geol, Madrid, Spain. [Karunatillake, Suniti] Cornell Univ, Ctr Radiophys & Space Res, Ithaca, NY 14853 USA. RP Dohm, JM (reprint author), Univ Arizona, Dept Hydrol & Water Resources, Tucson, AZ 85721 USA. RI Karunatillake, Suniti/A-5934-2009; Miyamoto, Hideaki/B-9666-2008; Miyamoto, Hideaki/E-3381-2012; Williams, Jean-Pierre/C-3531-2009; Dohm, James/A-3831-2014; de Pablo, Miguel Angel/J-6442-2014; OI Karunatillake, Suniti/0000-0001-9891-1432; Williams, Jean-Pierre/0000-0003-4163-2760; de Pablo, Miguel Angel/0000-0002-4496-2741; ORI, Gian Gabriele/0000-0002-6460-1476 NR 210 TC 33 Z9 33 U1 4 U2 20 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0032-0633 J9 PLANET SPACE SCI JI Planet Space Sci. PD MAY PY 2008 VL 56 IS 7 BP 985 EP 1013 DI 10.1016/j.pss.2008.01.001 PG 29 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 314RS UT WOS:000256827100012 ER PT J AU Polovina, JJ Chai, F Howell, EA Kobayashi, DR Shi, L Chao, Y AF Polovina, Jeffrey J. Chai, Fei Howell, Evan A. Kobayashi, Donald R. Shi, Lei Chao, Yi TI Ecosystem dynamics at a productivity gradient: A study of the lower trophic dynamics around the northern atolls in the Hawaiian Archipelago SO PROGRESS IN OCEANOGRAPHY LA English DT Article; Proceedings Paper CT Symposium on Climater Variability and Ecosystem Impacts on the North Pacific - A Basin-Scale Synthesis CY APR 19-21, 2006 CL Honolulu, HI SP PICES, GLOBEC Int ID PHYSICAL-BIOLOGICAL MODEL; PACIFIC UPWELLING SYSTEM; ZONE CHLOROPHYLL FRONT; OCEANIC MODEL; SURFACE; COORDINATE; CYCLE AB Application of a lower trophic ecosystem model coupled with an ocean circulation model allows us to derive a time series of estimated plankton biomass for waters around Kure Atoll, Pearl & Hermes Atoll and Midway Islands, over the period 1964-2006. This time series shows considerable interannual and decadal variation in productivity, and changes in recent years that are coherent with observed changes at higher trophic levels. Further the model results show that the change in productivity can be viewed from the perspective that the atolls, at the northern edge of the subtropical gyre, are situated at a strong physical, chemical and biological gradient. The gradient moves north and south seasonally and interannually resulting in changes in lower trophic level productivity around the atolls fixed in position. Variation in biome boundaries or gradients may be a key factor in ecosystem dynamics in many ecosystems located near such boundaries. Published by Elsevier Ltd. C1 [Polovina, Jeffrey J.; Howell, Evan A.; Kobayashi, Donald R.] NOAA Fisheries, Pacific Isl Fisheries Sci Ctr, Honolulu, HI 96822 USA. [Chai, Fei; Shi, Lei] Univ Maine, Sch Marine Sci, Orono, ME 04469 USA. [Chao, Yi] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Polovina, JJ (reprint author), NOAA Fisheries, Pacific Isl Fisheries Sci Ctr, 2570 Dole St, Honolulu, HI 96822 USA. EM jeffrey.polovina@noaa.gov OI Howell, Evan/0000-0001-9904-4633 NR 21 TC 20 Z9 23 U1 0 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0079-6611 J9 PROG OCEANOGR JI Prog. Oceanogr. PD MAY-JUN PY 2008 VL 77 IS 2-3 BP 217 EP 224 DI 10.1016/j.pocean.2008.03.011 PG 8 WC Oceanography SC Oceanography GA 317KE UT WOS:000257018000011 ER PT J AU Delay, T Patterson, J Noorda, J Schneider, J AF DeLay, T. Patterson, J. Noorda, J. Schneider, J. TI Development of cryogenic composite over-wrapped pressure vessels (COPV's) SO SAMPE JOURNAL LA English DT Article AB To meet the design goals for the NASA's new launch vehicles, the use of new high strength to weight ratio composite systems are being explored. NASA's new ARES-1 vehicle concept will utilize an upper stage common bulkhead liquid oxygen (LOX)/liquid hydrogen (LH2) design which requires 31.4 MPa gaseous helium (GHe) pressure vessels to be located inside the LH2 tank. In addition to this application, similar needs are emerging for cryogenic fuel storage tanks for commercial launch business and for transportation of liquefied natural gas and LH2. In all of these applications it is important to know the performance of the candidate materials at cryogenic temperatures to realize weight savings and to ensure safety and reliability. This document summarizes the results of a multi-year collaborative effort to develop material selection guidelines and evaluate cryogenic performance of composite over-wrapped pressure vessels (COPVs). This effort involved the simultaneous development and evaluation of materials, test methods, and tank design. As part of this study, material tests of candidate fiber and resin systems have been used as the basis for the selection of the material combinations for evaluation in a COPV at cryogenic conditions. This comprehensive approach has also been expanded to address issues with impact damage tolerance and material degradation due to environmental factors. C1 [DeLay, T.] NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. [Patterson, J.; Noorda, J.] HyPerComp Engn Inc, Brigham City, UT USA. [Schneider, J.] Mississippi State Univ, Mississippi State, MS USA. RP Delay, T (reprint author), NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. NR 3 TC 0 Z9 0 U1 1 U2 4 PU SAMPE PUBLISHERS PI COVINA PA 1161 PARKVIEW DRIVE, COVINA, CA 91722 USA SN 0091-1062 J9 SAMPE J JI Sampe J. PD MAY-JUN PY 2008 VL 44 IS 3 BP 44 EP 51 PG 8 WC Engineering, Multidisciplinary; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 297WC UT WOS:000255647100003 ER PT J AU Chaban, GM Gerber, RB AF Chaban, Galina M. Gerber, R. Benny TI Anharmonic vibrational spectroscopy calculations with electronic structure potentials: comparison of MP2 and DFT for organic molecules SO THEORETICAL CHEMISTRY ACCOUNTS LA English DT Article; Proceedings Paper CT Meeting on Practicing Chemistry with Theoretical Tools CY JAN 15-18, 2007 CL Maui, HI DE ab initio calculations; density functional calculations; electronic structure; vibrational anharmonicity; vibrational spectroscopy; vibrational self-consistent field ID SELF-CONSISTENT-FIELD; DENSITY-FUNCTIONAL THEORY; AB-INITIO CALCULATION; POLYATOMIC-MOLECULES; MATRIX-ISOLATION; FORCE-FIELDS; ENERGY SURFACES; WAVE-FUNCTIONS; IMIDAZOLE; SPECTRA AB Density functional theory (DFT) technique is the most commonly used approach when it comes to computation of vibrational spectra of molecular species. In this study, we compare anharmonic spectra of several organic molecules such as allene, propyne, glycine, and imidazole, computed from ab initio MP2 potentials and DFT potentials based on commonly used BLYP and B3LYP functionals. Anharmonic spectra are obtained using the direct vibrational self-consistent field (VSCF) method and its correlation-corrected extension (CC-VSCF). The results of computations are compared with available experimental data. It is shown that the most accurate vibrational frequencies are obtained with the MP2 method, followed by the DFT/B3LYP method, while DFT/BLYP results are often unsatisfactory. C1 [Chaban, Galina M.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. [Gerber, R. Benny] Hebrew Univ Jerusalem, Dept Phys Chem, IL-91904 Jerusalem, Israel. [Gerber, R. Benny] Univ Calif Irvine, Dept Chem, Irvine, CA 92697 USA. RP Chaban, GM (reprint author), NASA, Ames Res Ctr, Mail Stop T27B-1, Moffett Field, CA 94035 USA. EM gchaban@mail.arc.nasa.gov NR 38 TC 38 Z9 38 U1 0 U2 15 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1432-881X J9 THEOR CHEM ACC JI Theor. Chem. Acc. PD MAY PY 2008 VL 120 IS 1-3 BP 273 EP 279 DI 10.1007/s00214-007-0299-1 PG 7 WC Chemistry, Physical SC Chemistry GA 307HA UT WOS:000256308800022 ER PT J AU Weitkamp, LA AF Weitkamp, Laurie A. TI Buoyancy regulation by hatchery and wild coho salmon during the transition from freshwater to marine environments SO TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY LA English DT Article ID PARR-SMOLT TRANSFORMATION; TROUT ONCORHYNCHUS-MYKISS; PASSIVE INTEGRATED TRANSPONDERS; GAS SUPERSATURATED WATER; JUVENILE ATLANTIC SALMON; COLUMBIA RIVER ESTUARY; CHINOOK SALMON; VERTICAL-DISTRIBUTION; BIOCHEMICAL CHANGES; SWIMBLADDER VOLUME AB One aspect of diadromy that has received little attention is buoyancy regulation in fish moving between freshwater and marine environments. Because of density differences between the two water types, fish must alter their whole-fish density (WFD) or they will become positively (float) or negatively (sink) buoyant as they change environments. This idea was first suggested over 80 year ago but has been largely overlooked by the scientific community. To explore how fish regulate buoyancy during this important transition, I measured WFD and lipid levels and estimated swim bladder volumes (SBVs) of juvenile coho salmon Oncorhynchus kisutch collected from freshwater and marine environments. These fish exhibited increased WFD with increasingly dense environments, suggesting active buoyancy regulation. Most of the WFD increase was attributable to decreases in SBV, although hatchery coho salmon also exhibited decreased lipid levels with increasing WFD. Hatchery coho salmon had significantly higher lipid levels than wild coho salmon in both freshwater and marine environments. These high lipid levels may impede the ability of hatchery fish to regulate buoyancy and may increase their vulnerability to surface predators. Furthermore, lipid levels that vary with both environmental water density and fish origin clearly complicate the interpretation of this variable during the important transition from freshwater to the ocean. C1 NW Fisheries Sci Ctr, Natl Marine Fisheries Serv, Newport Res Stn, Newport, OR 97365 USA. RP Weitkamp, LA (reprint author), NW Fisheries Sci Ctr, Natl Marine Fisheries Serv, Newport Res Stn, 2032 SE OSU Dr, Newport, OR 97365 USA. EM laurie.weitkamp@noaa.gov NR 70 TC 3 Z9 3 U1 2 U2 7 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 USA SN 0002-8487 J9 T AM FISH SOC JI Trans. Am. Fish. Soc. PD MAY PY 2008 VL 137 IS 3 BP 860 EP 868 DI 10.1577/T07-081.1 PG 9 WC Fisheries SC Fisheries GA 306ZU UT WOS:000256288000019 ER PT J AU Ene, NM Dimofte, F Keith, TG AF Ene, Nicoleta M. Dimofte, Florin Keith, Theo G., Jr. TI A stability analysis for a hydrodynamic three-wave journal bearing SO TRIBOLOGY INTERNATIONAL LA English DT Article DE bearing stability; wave bearing; oil inlet pressure ID BEHAVIOR AB The influence of the wave amplitude and oil supply pressure on the dynamic behavior of a hydrodynamic three-wave journal bearing is presented. Both, a transient and a small perturbation technique, were used to predict the threshold to fractional frequency whirl (FFW). In addition, the behavior of the rotor after FFW appeared was determined from the transient analysis. The turbulent effects were also included in the computations. Bearings having a diameter of 30 mm, a length of 27.5 mm, and a clearance of 35 pm were analyzed. Numerical results were compared to experimental results obtained at the NASA GRC. Numerical and experimental results showed that the above-mentioned wave bearing with a wave amplitude ratio of 0.305 operates stably at rotational speeds up to 60,000 rpm, regardless of the oil supply pressure. For smaller wave amplitude ratios, a threshold of stability was found. It was observed that the threshold of stability for lower wave amplitude strongly depends on the oil supply pressure and on the wave amplitude. When the FFW occurs, the journal center maintains its trajectory inside the bearing clearance and therefore the rotor can be run safely without damaging the bearing surfaces. (c) 2007 Elsevier Ltd. All rights reserved. C1 [Ene, Nicoleta M.; Keith, Theo G., Jr.] Univ Toledo, Dept Mech Engn, Toledo, OH 43606 USA. [Dimofte, Florin] Univ Toledo, NASA, Glenn Res Ctr, Cleveland, OH USA. RP Ene, NM (reprint author), Univ Toledo, Dept Mech Engn, 2801 W Bancroft Rd,MS 312, Toledo, OH 43606 USA. EM nene@eng.utoledo.edu; Forin.Dimofte@grc.nasa.gov; tkeith@eng.utoledo.edu NR 24 TC 16 Z9 21 U1 1 U2 9 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0301-679X EI 1879-2464 J9 TRIBOL INT JI Tribol. Int. PD MAY PY 2008 VL 41 IS 5 SI SI BP 434 EP 442 DI 10.1016/j.triboint.2007.10.002 PG 9 WC Engineering, Mechanical SC Engineering GA 268MM UT WOS:000253583900011 ER PT J AU Krzyscin, JW Jaroslawski, J Rajewska-Wiech, B Sobolewski, PS Froidevaux, L AF Krzyscin, J. W. Jaroslawski, J. Rajewska-Wiech, B. Sobolewski, P. S. Froidevaux, L. TI Comparison of ozone profiles by the Umkehr measurements taken at Belsk (52 degrees N, 21 degrees E) with the Aura Microwave Limb Sounder overpasses: 2004-2006 SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID EOS-MLS; SATELLITE AB A comparison of ozone profile measurements by the Umkehr observations taken at Belsk (52 degrees N, 21 degrees E) by the Dobson spectrophotometer and collocated Earth Observing System (EOS) Microwave Limb Sounder (MLS) aboard the Aura platform during 2004-2006 site overpasses is presented. The MLS ozone vertical profiles from 1.5 and 2.2 retrieval algorithms and various Umkehr retrievals are considered. There is a good agreement between the ozone content in Umkehr layers. The mean difference similar to +/- 5%, standard deviation of the relative differences < 10%, and the correlation coefficient > 0.5 are found in the midstratosphere (Umkehr layers 5-7) and in the upper stratosphere (combined layers 8, 9, and 10). In the lower stratosphere (combined layers 2 and 3 and layer 4) the mean difference and/or standard deviation are larger but the correlation coefficient is still high (similar to 0.8). Ozone content in Umkehr layers by integration of MLS version 1.5 and 2.2 ozone mixing ratio profiles behaves very similarly in the comparisons with the ground-based data. C1 [Krzyscin, J. W.; Jaroslawski, J.; Rajewska-Wiech, B.; Sobolewski, P. S.] Polish Acad Sci, Inst Geophys, PL-01452 Warsaw, Poland. [Froidevaux, L.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Krzyscin, JW (reprint author), Polish Acad Sci, Inst Geophys, 64 Ks Janusza St, PL-01452 Warsaw, Poland. EM jkrzys@igf.edu.pl NR 17 TC 5 Z9 5 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 30 PY 2008 VL 113 IS D15 AR D15S09 DI 10.1029/2007JD008586 PG 7 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 297CI UT WOS:000255594300001 ER PT J AU Song, CK Byun, DW Pierce, RB Alsaadi, JA Schaack, TK Vukovich, F AF Song, C. -K. Byun, D. W. Pierce, R. B. Alsaadi, J. A. Schaack, T. K. Vukovich, F. TI Downscale linkage of global model output for regional chemical transport modeling: Method and general performance SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID STRATOSPHERE-TROPOSPHERE EXCHANGE; OZONE OBSERVATIONS; CLIMATE-CHANGE; ART.; CHEMISTRY; QUALITY; SYSTEM; VALIDATION; POLLUTION; PROFILES AB The goal of this study is to assess the impact of the downscale linkage of global chemistry model output on the simulated regional scale O-3 concentration and its vertical and horizontal structure over the continental US. For the global chemistry model, the NASA LaRC-University of Wisconsin Real-time Air Quality Modeling System (RAQMS) with a global ozone assimilation framework was used. RAQMS simulation results were downscaled with a RAQMS-CMAQ linkage tool (RAQ2CMAQ) to provide dynamic lateral boundary conditions for regional air quality simulations with the EPA Models-3 Community Multiscale Air Quality (CMAQ) Model. We performed two sets of CMAQ simulations; (1) with the predefined lateral boundary condition profile representing relatively clean air conditions in the eastern-half of the United States, and (2) with the lateral boundary conditions generated from RAQMS 6 hourly analyses, for the 1999 Southern Oxidant Study (SOS-99) period (15 June-14 July 1999). When compared and evaluated with available ozone soundings and nation wide surface observations (AIRS/EPA) in U. S., CMAQ simulations with the lateral boundary condition from the predefined profile failed to simulate the so-called "chemical tropopause'' above which O-3 concentration rapidly increases with height. On the other hand, the simulations with the lateral boundary condition provided with the global RAQMS output not only improved diurnal variations and daily maxima of surface O-3 concentrations, but also produced better agreement with the vertical structure of O-3 measured in the middle and upper troposphere. The tracer mode CMAQ simulations showed that, at the upper troposphere, more than 85% of the O-3 concentration difference associated with the lateral BCs was caused by the transport and diffusion processes. C1 [Song, C. -K.; Byun, D. W.] Univ Houston, Dept Geosci, IMAQS, Houston, TX 77204 USA. [Alsaadi, J. A.] NASA, Langley Res Ctr, Hampton, VA 23665 USA. [Pierce, R. B.] STAR, NESDIS, NOAA, Madison, WI USA. [Schaack, T. K.] Univ Wisconsin, Ctr Space Sci & Engn, Madison, WI USA. [Vukovich, F.] Sci Applicat Int Corp, Raleigh, NC USA. RP Song, CK (reprint author), Univ Houston, Dept Geosci, IMAQS, Sci & Res Bldg 1,Rm 312,4800 Calhoun Rd, Houston, TX 77204 USA. EM daewon.byun@mail.uh.edu RI Pierce, Robert Bradley/F-5609-2010; Kwon, Yulee/B-8433-2009; Song, Chang-Keun/S-2255-2016 OI Pierce, Robert Bradley/0000-0002-2767-1643; Kwon, Yulee/0000-0002-6515-9181; Song, Chang-Keun/0000-0002-8811-2626 NR 35 TC 15 Z9 15 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 30 PY 2008 VL 113 IS D8 AR D08308 DI 10.1029/2007JD008951 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 297CE UT WOS:000255593900003 ER PT J AU Wu, DL Jiang, JH Read, WG Austin, RT Davis, CP Lambert, A Stephens, GL Vane, DG Waters, JW AF Wu, Dong L. Jiang, Jonathan H. Read, William G. Austin, Richard T. Davis, Cory P. Lambert, Alyn Stephens, Graeme L. Vane, Deborah G. Waters, Joe W. TI Validation of the Aura MLS cloud ice water content measurements SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID MICROWAVE LIMB SOUNDER; PARTICLE-SIZE DISTRIBUTIONS; RADIATIVE-TRANSFER MODEL; VISIBLE OPTICAL DEPTH; RADAR DATA; EOS MLS; RETRIEVAL ALGORITHMS; IMAGING RADIOMETER; TROPICAL CIRRUS; 183 GHZ AB Retrieval and validation of upper tropospheric ice water content (IWC) measurements with the Aura Microwave Limb Sounder (MLS) are described. The MLS version 2.2 (V2.2) IWC, derived from 240-GHz cloud-induced radiances (Tcir) at high tangent heights, is scientifically useful at 215-83 hPa. The V2.2 IWC represents a bulk cloud property averaged over a similar to 300 x 7 x 4 km(3) volume near the pointing tangent height. Precision, accuracy, and spatial resolution of the V2.2 IWC are determined through model simulations and comparisons with CloudSat observations. Comparisons of MLS V2.2 and CloudSat R03 IWCs are made for the months of January and July in terms of normalized probability density function (PDF). The differences between MLS and CloudSat IWC PDFs are generally less than 50% over the IWC range where the MLS technique is valid. At pressures < 177 hPa and extratropical latitudes, the MLS V2.2 IWC exhibits a slightly low bias compared to CloudSat, part of which can be attributed to systematic errors in the MLS retrieval. Cloud inhomogeneity and particle size distribution are the leading sources of uncertainties in the V2.2 IWC. C1 [Wu, Dong L.; Jiang, Jonathan H.; Read, William G.; Lambert, Alyn; Vane, Deborah G.; Waters, Joe W.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Austin, Richard T.; Stephens, Graeme L.] Colorado State Univ, Dept Atmospher Sci, Ft Collins, CO 80523 USA. [Davis, Cory P.] Meteorol Serv New Zealand Ltd, Wellington 6140, New Zealand. RP Wu, DL (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM dwu@mls.jpl.nasa.gov RI Wu, Dong/D-5375-2012 NR 56 TC 46 Z9 47 U1 0 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 30 PY 2008 VL 113 IS D15 AR D15S10 DI 10.1029/2007JD008931 PG 20 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 297CI UT WOS:000255594300002 ER PT J AU Ionov, DV Timofeyev, YM Sinyakov, VP Semenov, VK Goutail, F Pommereau, JP Bucsela, EJ Celarier, EA Kroon, M AF Ionov, D. V. Timofeyev, Y. M. Sinyakov, V. P. Semenov, V. K. Goutail, F. Pommereau, J. -P. Bucsela, E. J. Celarier, E. A. Kroon, M. TI Ground-based validation of EOS-Aura OMI NO2 vertical column data in the midlatitude mountain ranges of Tien Shan (Kyrgyzstan) and Alps (France) SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ZENITH-SKY SPECTROMETERS; AIR-MASS FACTORS; OZONE MONITORING INSTRUMENT; RADIATIVE-TRANSFER MODELS; STRATOSPHERIC GASES; TROPOSPHERIC CLOUDS; SATELLITE; GOME; OBJECTIVES; PARAMETERS AB Ground-based UV-visible instruments for NO2 vertical column measurements have been operating at Issyk-Kul station, in Kyrgyzstan, and Observatoire de Haute-Provence (OHP), in France, since 1983 and 1992, respectively. These measurements have already been used for validation of ERS-2 Global Ozone Monitoring Experiment (GOME) and Envisat Scanning Imaging Absorption Spectrometer for Atmospheric Cartography (SCIAMACHY) NO2 column data. Building upon the successful missions of GOME and SCIAMACHY, the Ozone Monitoring Experiment (OMI) was launched by NASA onboard the EOS Aura satellite in July 2004. Here we present the results of recent comparisons between OMI NO2 operational data (standard product) and correlative ground-based twilight measurements in midlatitudes, at Issyk-Kul and OHP, in 2004-2006. The stratospheric NO2 columns, observed by OMI and our ground-based instruments, have been corrected for NO2 diurnal change and normalized to local noon values using a photochemical box model. According to our comparison, OMI stratospheric NO2 columns underestimate ground-based measurements by (0.3 +/- 0.3) x 10(15) molecules/cm(2) and (0.7 +/- 0.6) x 10(15) molecules/cm(2) at Issyk-Kul and OHP, respectively. The effect of tropospheric pollution on the NO2 measurements in both regions of observations has been identified and discussed. C1 [Ionov, D. V.; Timofeyev, Y. M.] St Petersburg State Univ, Inst Phys Res, St Petersburg 198904, Russia. [Goutail, F.; Pommereau, J. -P.] CNRS, Serv Aeron, F-91371 Verrieres Le Buisson, France. [Sinyakov, V. P.; Semenov, V. K.] Kyrgyz Natl Univ, Bishkek 720033, Kyrgyzstan. [Bucsela, E. J.; Celarier, E. A.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Kroon, M.] Royal Netherlands Meteorol Inst, NL-3730 AE De Bilt, Netherlands. RP Ionov, DV (reprint author), St Petersburg State Univ, Inst Phys Res, Ulyanovskaya Str 1, St Petersburg 198904, Russia. EM ionov@troll.phys.spbu.ru RI Ionov, Dmitry/J-4461-2013; Timofeev, Yuriy/K-1618-2013 OI Ionov, Dmitry/0000-0002-4844-5397; Timofeev, Yuriy/0000-0003-2771-9931 NR 36 TC 21 Z9 21 U1 0 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 29 PY 2008 VL 113 IS D15 AR D15S08 DI 10.1029/2007JD008659 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 297CH UT WOS:000255594200001 ER PT J AU Diao, J Srivastava, D Menon, M AF Diao, Jiankuai Srivastava, Deepak Menon, Madhu TI Molecular dynamics simulations of carbon nanotube/silicon interfacial thermal conductance SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID CONDUCTIVITY; NANOTUBES; TEMPERATURE; FILMS AB Using molecular dynamics simulations with Tersoff reactive many-body potential for Si-Si, Si-C, and C-C interactions, we have calculated the thermal conductance at the interfaces between carbon nanotube (CNT) and silicon at different applied pressures. The interfaces are formed by axially compressing and indenting capped or uncapped CNTs against 2x1 reconstructed Si surfaces. The results show an increase in the interfacial thermal conductance with applied pressure for interfaces with both capped and uncapped CNTs. At low applied pressure, the thermal conductance at interface with uncapped CNTs is found to be much higher than that at interface with capped CNTs. Our results demonstrate that the contact area or the number of bonds formed between the CNT and Si substrate is key to the interfacial thermal conductance, which can be increased by either applying pressure or by opening the CNT caps that usually form in the synthesis process. The temperature and size dependences of interfacial thermal conductance are also simulated. These findings have important technological implications for the application of vertically aligned CNTs as thermal interface materials. (C) 2008 American Institute of Physics. C1 [Diao, Jiankuai; Srivastava, Deepak] Univ Calif Santa Cruz, Univ Affiliated Res Ctr, Santa Cruz, CA 94035 USA. [Diao, Jiankuai; Srivastava, Deepak] NASA, Ames Ctr Nanotechnol, Moffett Field, CA 94035 USA. [Menon, Madhu] Univ Kentucky, Dept Phys & Astron, Lexington, KY 40506 USA. [Menon, Madhu] Univ Kentucky, Ctr Computat Sci, Lexington, KY 40506 USA. RP Diao, J (reprint author), Univ Calif Santa Cruz, Univ Affiliated Res Ctr, Santa Cruz, CA 94035 USA. EM jkdiao@ucsc.edu; deepak@nas.nasa.gov; madhu@ccs.uky.edu NR 23 TC 47 Z9 47 U1 1 U2 21 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-9606 EI 1089-7690 J9 J CHEM PHYS JI J. Chem. Phys. PD APR 28 PY 2008 VL 128 IS 16 AR 164708 DI 10.1063/1.2905211 PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 295DX UT WOS:000255456300069 PM 18447480 ER PT J AU Perlwitz, J Pawson, S Fogt, RL Nielsen, JE Neff, WD AF Perlwitz, Judith Pawson, Steven Fogt, Ryan L. Nielsen, J. Eric Neff, William D. TI Impact of stratospheric ozone hole recovery on Antarctic climate SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID HEMISPHERE ATMOSPHERIC CIRCULATION; SOUTHERN ANNULAR MODE; TRENDS; TROPOSPHERE AB Model experiments have revealed that stratospheric polar ozone depletion and anthropogenic increase of greenhouse gases (GHG) have both contributed to the observed increase of summertime tropospheric westerlies in the Southern Hemisphere (SH) with the ozone influence dominating. As the stratospheric halogen loading decreases in the future, ozone is expected to return to higher values, with the disappearance of the Antarctic ozone hole. The impact of this ozone recovery on SH climate is investigated using 21st century simulations with a chemistry climate model (CCM). The model response to the ozone recovery by 2100 shows that tropospheric circulation changes during austral summer caused by ozone depletion between 1970 and 2000 almost reverse, despite increasing GHG concentrations. Comparison of the CCM results with multi-model scenario experiments from the Fourth Assessment Report (AR4) by the Intergovernmental Panel on Climate Change (IPCC) emphasize the importance of stratospheric ozone recovery for Antarctic climate. C1 [Perlwitz, Judith; Fogt, Ryan L.; Neff, William D.] NOAA, Div Phys Sci, Earth Syst Res Lab, Boulder, CO 80305 USA. [Pawson, Steven; Nielsen, J. Eric] NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Greenbelt, MD 20771 USA. [Perlwitz, Judith] Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO USA. RP Perlwitz, J (reprint author), NOAA, Div Phys Sci, Earth Syst Res Lab, 325 Broadway, Boulder, CO 80305 USA. EM judith.perlwitz@noaa.gov RI Perlwitz, Judith/B-7201-2008; Fogt, Ryan/B-6989-2008; Neff, William/E-2725-2010; Pawson, Steven/I-1865-2014 OI Perlwitz, Judith/0000-0003-4061-2442; Fogt, Ryan/0000-0002-5398-3990; Neff, William/0000-0003-4047-7076; Pawson, Steven/0000-0003-0200-717X NR 21 TC 134 Z9 134 U1 2 U2 15 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 EI 1944-8007 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR 26 PY 2008 VL 35 IS 8 AR L08714 DI 10.1029/2008GL033317 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 295EW UT WOS:000255458800002 ER PT J AU Schwartz, MJ Waliser, DE Tian, BJ Wu, DL Jiang, JH Read, WG AF Schwartz, Michael J. Waliser, Duane E. Tian, Baijun Wu, Dong L. Jiang, Jonathan H. Read, William G. TI Characterization of MJO-related upper tropospheric hydrological processes using MLS SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID MADDEN-JULIAN OSCILLATION; ASIAN SUMMER MONSOON; INTRASEASONAL VARIABILITY; VERTICAL STRUCTURE; WATER-VAPOR; MODELS; PRECIPITATION; SIMULATIONS; SYSTEM; BUDGET AB This study quantifies Madden-Julian Oscillation (MJO)-related hydrological variability in the upper troposphere/lower stratosphere (UT/LS) using Aura Microwave Limb Sounder (MLS) cloud ice water content (IWC) and water vapor (H2O). In a composite of six boreal-winter MJO events, the UT/LS IWC anomaly is strongly positively correlated with the convection (TRMM rainfall) anomaly. IWC anomalies range from +/- 2 mg/m(3) at 215 hPa to +/- 0.08 mg/m(3) at 100 hPa. The UT/LS H2O anomaly has an eastward-tilting structure similar to the previous-documented temperature structure, but the H2O maximum lags the temperature maximum by about a week. The H2O anomaly is positively correlated with the convection anomaly in the UT (261 hPa) and LS (68 hPa) but negatively correlated with the convection anomaly near the tropopause (100 hPa). This analysis provides a multi-parameter construct useful in validating and improving the parameterization of convection, clouds and cloud microphysics in MJO modeling. C1 [Schwartz, Michael J.; Waliser, Duane E.; Wu, Dong L.; Jiang, Jonathan H.; Read, William G.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Tian, Baijun] Univ Calif Los Angeles, Joint Inst Reg Earth Syst Sci & Engn, Los Angeles, CA 90024 USA. RP Schwartz, MJ (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM michael.j.schwartz@jpl.nasa.gov RI Tian, Baijun/A-1141-2007; Schwartz, Michael/F-5172-2016; Wu, Dong/D-5375-2012 OI Tian, Baijun/0000-0001-9369-2373; Schwartz, Michael/0000-0001-6169-5094; NR 35 TC 14 Z9 14 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 EI 1944-8007 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR 26 PY 2008 VL 35 IS 8 AR L08812 DI 10.1029/2008GL033675 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 295EW UT WOS:000255458800005 ER PT J AU Menon, S Del Genio, AD Kaufman, Y Bennartz, R Koch, D Loeb, N Orlikowski, D AF Menon, Surabi Del Genio, Anthony D. Kaufman, Yoram Bennartz, Ralf Koch, Dorothy Loeb, Norman Orlikowski, Daniel TI Analyzing signatures of aerosol-cloud interactions from satellite retrievals and the GISS GCM to constrain the aerosol indirect effect SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID STRATIFORM CLOUDS; CLIMATE MODELS; SENSITIVITY; PARAMETERIZATION; MICROPHYSICS; SIMULATIONS; CUMULUS AB Evidence of aerosol-cloud interactions is evaluated using satellite data from MODIS, CERES, and AMSR-E; reanalysis data from NCEP; and data from the NASA Goddard Institute for Space Studies climate model. We evaluate a series of model simulations: (1) Exp N, aerosol direct radiative effects; (2) Exp C, like Exp N but with aerosol effects on liquid-phase cumulus and stratus clouds; and (3) Exp CN, like Exp C but with model wind fields nudged to reanalysis data. Comparison between satellite-retrieved data and model simulations for June to August 2002 over the Atlantic Ocean indicate the following: a negative correlation between aerosol optical thickness (AOT) and cloud droplet effective radius (R-eff) for all cases and satellite data, except for Exp N, a weak but negative correlation between liquid water path (LWP) and AOT for MODIS and CERES, and a robust increase in cloud cover with AOT for both MODIS and CERES. In all simulations, there is a positive correlation between AOT and both cloud cover and LWP (except in the case of LWP-AOT for Exp CN). The largest slopes are obtained for Exp N, implying that meteorological variability may be an important factor. On the basis of NCEP data, warmer temperatures and increased subsidence were found for less clean cases (AOT > 0.06) that were not well captured by the model. Simulated cloud fields compared with an enhanced data product from MODIS and AMSR-E indicate that model cloud thickness is overpredicted and cloud droplet number is within retrieval uncertainties. Since LWP fields are comparable, this implies an underprediction of R-eff and thus an overprediction of the indirect effect. C1 [Menon, Surabi] Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. [Bennartz, Ralf] Univ Wisconsin, Dept Atmospher & Ocean Sci, Madison, WI USA. [Loeb, Norman] NASA, Langley Res Ctr, Hampton, VA USA. [Orlikowski, Daniel] Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. [Del Genio, Anthony D.; Koch, Dorothy] NASA, Goddard Inst Space Studies, New York, NY 10025 USA. [Kaufman, Yoram] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Koch, Dorothy] Columbia Univ, Ctr Climate Syst Res, New York, NY USA. RP Menon, S (reprint author), Lawrence Berkeley Natl Lab, 1 Cyclotron Road,MS90KR109, Berkeley, CA 94720 USA. EM smenon@lbl.gov RI Del Genio, Anthony/D-4663-2012; Bennartz, Ralf/F-3760-2010 OI Del Genio, Anthony/0000-0001-7450-1359; NR 38 TC 25 Z9 25 U1 1 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 26 PY 2008 VL 113 IS D14 AR D14S22 DI 10.1029/2007JD009442 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 295FG UT WOS:000255459800001 ER PT J AU Eastwood, JP Sibeck, DG Angelopoulos, V Phan, TD Bale, SD McFadden, JP Cully, CM Mende, SB Larson, D Frey, S Carlson, CW Glassmeier, KH Auster, HU Roux, A Le Contel, O AF Eastwood, J. P. Sibeck, D. G. Angelopoulos, V. Phan, T. D. Bale, S. D. McFadden, J. P. Cully, C. M. Mende, S. B. Larson, D. Frey, S. Carlson, C. W. Glassmeier, K. -H. Auster, H. U. Roux, A. Le Contel, O. TI THEMIS observations of a hot flow anomaly: Solar wind, magnetosheath, and ground-based measurements SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID EARTHS BOW SHOCK; MAGNETOSPHERIC RESPONSE; HYBRID SIMULATION; DISCONTINUITY AB The THEMIS spacecraft encountered a Hot Flow Anomaly ( HFA) on the dusk flank of the Earth's bow shock on 4 July 2007, observing it on both sides of the shock. Meanwhile, the THEMIS ground magnetometers traced the progress of the associated Magnetic Impulse Event along the dawn flank of the magnetosphere, providing a unique opportunity to study the transmission of the HFA through the shock and the subsequent downstream response. THEMIS-A, in the solar wind, observed classic HFA signatures. Isotropic electron distributions inside the upstream HFA are attributed to the action of the electron firehose instability. THEMIS-E, just downstream, observed a much more complex disturbance with the pressure perturbation decoupled from the underlying discontinuity. Simple calculations show that the pressure perturbation would be capable of significantly changing the magnetopause location, which is confirmed by the ground-based observations. C1 [Eastwood, J. P.; Phan, T. D.; Bale, S. D.; McFadden, J. P.; Mende, S. B.; Larson, D.; Frey, S.; Carlson, C. W.] Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. [Sibeck, D. G.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Angelopoulos, V.] Univ Calif Los Angeles, ESS, IGPP, Los Angeles, CA 90095 USA. [Bale, S. D.] Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. [Cully, C. M.] Univ Colorado, LASP, Boulder, CO 80309 USA. [Cully, C. M.] Swedish Inst Space Phys, SE-75121 Uppsala, Sweden. [Glassmeier, K. -H.; Auster, H. U.] Tech Univ Carolo Wilhelmina Braunschweig, IGEP, D-38106 Braunschweig, Germany. [Roux, A.; Le Contel, O.] IPSL, CETP, F-78140 Velizy Villacoublay, France. RP Eastwood, JP (reprint author), Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. EM eastwood@ssl.berkeley.edu RI Bale, Stuart/E-7533-2011; Sibeck, David/D-4424-2012; Cully, Christopher/P-2539-2016 OI Bale, Stuart/0000-0002-1989-3596; NR 22 TC 32 Z9 32 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR 25 PY 2008 VL 35 IS 17 AR L17S03 DI 10.1029/2008GL033475 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 295EY UT WOS:000255459000001 ER PT J AU Reale, O Susskind, J Rosenberg, R Brin, E Liu, E Riishojgaard, LP Terry, J Jusem, JC AF Reale, O. Susskind, J. Rosenberg, R. Brin, E. Liu, E. Riishojgaard, L. P. Terry, J. Jusem, J. C. TI Improving forecast skill by assimilation of quality-controlled AIRS temperature retrievals under partially cloudy conditions SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article AB The National Aeronautics and Space Administration (NASA) Atmospheric Infrared Sounder (AIRS) on board the Aqua satellite is now recognized as an important contributor towards the improvement of weather forecasts. At this time only a small fraction of the total data produced by AIRS is being used by operational weather systems. In fact, in addition to effects of thinning and quality control, the only AIRS data assimilated are radiance observations of channels unaffected by clouds. Observations in mid-lower tropospheric sounding AIRS channels are assimilated primarily under completely clear-sky conditions, thus imposing a very severe limitation on the horizontal distribution of the AIRS-derived information. In this work it is shown that the ability to derive accurate temperature profiles from AIRS observations in partially cloud-contaminated areas can be utilized to further improve the impact of AIRS observations in a global model and forecasting system. The analyses produced by assimilating AIRS temperature profiles obtained under partial cloud cover result in a substantially colder representation of the northern hemisphere lower midtroposphere at higher latitudes. This temperature difference has a strong impact, through hydrostatic adjustment, in the midtropospheric geopotential heights, which causes a different representation of the polar vortex especially over northeastern Siberia and Alaska. The AIRS-induced anomaly propagates through the model's dynamics producing improved 5-day forecasts. C1 [Reale, O.; Susskind, J.; Jusem, J. C.] NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. [Reale, O.; Riishojgaard, L. P.; Jusem, J. C.] Univ Maryland, Goddard Earth Sci & Technol Ctr, Baltimore, MD USA. [Rosenberg, R.; Brin, E.; Terry, J.] NASA, Goddard Space Flight Ctr, Software Integrat & Visualizat Off, Greenbelt, MD 20771 USA. [Rosenberg, R.; Brin, E.; Liu, E.; Terry, J.] Sci Applicat Int Corp, Beltsville, MD USA. [Liu, E.; Riishojgaard, L. P.] NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Greenbelt, MD 20771 USA. [Riishojgaard, L. P.] Joint Ctr Satellite Data Assimilat, Camp Springs, MD USA. RP Reale, O (reprint author), NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. NR 18 TC 32 Z9 32 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR 25 PY 2008 VL 35 IS 8 AR L08809 DI 10.1029/2007GL033002 PG 6 WC Geosciences, Multidisciplinary SC Geology GA 295EV UT WOS:000255458700003 ER PT J AU Carvalhais, N Reichstein, M Seixas, J Collatz, GJ Pereira, JS Berbigier, P Carrara, A Granier, A Montagnani, L Papale, D Rambal, S Sanz, MJ Valentini, R AF Carvalhais, Nuno Reichstein, Markus Seixas, Julia Collatz, G. James Pereira, Joao Santos Berbigier, Paul Carrara, Arnaud Granier, Andre Montagnani, Leonardo Papale, Dario Rambal, Serge Sanz, Maria Jose Valentini, Riccardo TI Implications of the carbon cycle steady state assumption for biogeochemical modeling performance and inverse parameter retrieval SO GLOBAL BIOGEOCHEMICAL CYCLES LA English DT Article ID NET ECOSYSTEM EXCHANGE; ORGANIC-MATTER DECOMPOSITION; GROSS PRIMARY PRODUCTION; SOIL RESPIRATION; MEDITERRANEAN ECOSYSTEMS; TEMPERATURE-DEPENDENCE; TERRESTRIAL BIOSPHERE; PRIMARY PRODUCTIVITY; GLOBAL SATELLITE; EUROPEAN FORESTS AB We analyze the impacts of the steady state assumption on inverse model parameter retrieval from biogeochemical models. An inverse model parameterization study using eddy covariance CO(2) flux data was performed with the Carnegie Ames Stanford Approach (CASA) model under conditions of strict and relaxed carbon cycle steady state assumption (CCSSA) in order to evaluate both the robustness of the model's structure for the simulation of net ecosystem carbon fluxes and the assessment of the CCSSA effects on simulations and parameter estimation. Net ecosystem production (NEP) measurements from several eddy covariance sites were compared with NEP estimates from the CASA model driven by local weather station climate inputs as well as by remotely sensed fraction of photosynthetically active radiation absorbed by vegetation and leaf area index. The parameters considered for optimization are directly related to aboveground and belowground modeled responses to temperature and water availability, as well as a parameter (eta) that relaxed the CCSSA in the model, allowing for site level simulations to be initialized either as net sinks or sources. A robust relationship was observed between NEP observations and predictions for most of the sites through the range of temporal scales considered (daily, weekly, biweekly, and monthly), supporting the conclusion that the model structure is able to capture the main processes explaining NEP variability. Overall, relaxing CCSSA increased model efficiency (21%) and decreased normalized average error (-92%). Intersite variability was a major source of variance in model performance differences between fixed (CCSSA(f)) and relaxed (CCSSA(r)) CCSSA conditions. These differences were correlated with mean annual NEP observations, where an average increase in modeling efficiency of 0.06 per 100 g C m(-2) a(-1) (where a is years) of NEP is observed (alpha < 0.003). The parameter eta was found to be a key parameter in the optimization exercise, generating significant model efficiency losses when removed from the initial parameter set and parameter uncertainties were significantly lower under CCSSA(r). Moreover, modeled soil carbon stocks were generally closer to observations once the steady state assumption was relaxed. Finally, we also show that estimates of individual parameters are affected by the steady state assumption. For example, estimates of radiation-use efficiency were strongly affected by the CCSSA(f) indicating compensation effects for the inadequate steady state assumption, leading to effective and thus biased parameters. Overall, the importance of model structural evaluation in data assimilation approaches is thus emphasized. C1 [Carvalhais, Nuno; Seixas, Julia] Univ Nova Lisboa, Fac Ciencias & Tecnol, P-2829516 Caparica, Portugal. [Carvalhais, Nuno; Reichstein, Markus] Max Planck Inst Biogeochem, D-07701 Jena, Germany. [Collatz, G. James] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Pereira, Joao Santos] Inst Super Agron Tapada Ajuda, Lisbon, Portugal. [Berbigier, Paul] Inst Natl Rech Agron, Ecol Fonct & Phys Environm, IR1263, Bordeaux, France. [Carrara, Arnaud; Sanz, Maria Jose] Estudios Ambientales Mediterraneo, Fund Ctr, Valencia, Spain. [Granier, Andre] Inst Natl Rech Agron, Ecol Ecophysiol Forestieres, Ctr Nancy, Champenoux, France. [Montagnani, Leonardo] Prov Autonoma Bolzano, Serv Forestali Agenzia Ambiente, Bolzano, Italy. [Papale, Dario; Valentini, Riccardo] Univ Tuscia, Dept Forest Environm & Resources, Viterbo, Italy. [Rambal, Serge] CNRS, Ctr Ecol Fonct & Evolut, DREAM Unit, F-34033 Montpellier, France. RP Carvalhais, N (reprint author), Univ Nova Lisboa, Fac Ciencias & Tecnol, P-2829516 Caparica, Portugal. EM ncarvalhais@fct.unl.pt; nmmc@fct.unl.pt RI Reichstein, Markus/A-7494-2011; Valentini, Riccardo/D-1226-2010; collatz, george/D-5381-2012; Seixas, Julia/K-9400-2013; Carrara, Arnaud/L-8144-2014; Sanz Sanchez, Maria Jose/A-6099-2016; Vuichard, Nicolas/A-6629-2011; Montagnani, Leonardo/F-1837-2016; OI rambal, serge/0000-0001-5869-8382; Papale, Dario/0000-0001-5170-8648; Reichstein, Markus/0000-0001-5736-1112; Valentini, Riccardo/0000-0002-6756-5634; Seixas, Julia/0000-0003-0355-0465; Sanz Sanchez, Maria Jose/0000-0003-0471-3094; Montagnani, Leonardo/0000-0003-2957-9071; Pereira, Joao/0000-0002-3658-5587; Carvalhais, Nuno/0000-0003-0465-1436 NR 81 TC 50 Z9 50 U1 2 U2 27 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0886-6236 J9 GLOBAL BIOGEOCHEM CY JI Glob. Biogeochem. Cycle PD APR 25 PY 2008 VL 22 IS 2 AR GB2007 DI 10.1029/2007GB003033 PG 16 WC Environmental Sciences; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Geology; Meteorology & Atmospheric Sciences GA 295FA UT WOS:000255459200002 ER PT J AU Feng, L Brugge, R Holm, EV Harwood, RS O'Neill, A Filipiak, MJ Froidevaux, L Livesey, N AF Feng, Liang Brugge, R. Holm, E. V. Harwood, R. S. O'Neill, A. Filipiak, M. J. Froidevaux, L. Livesey, N. TI Four-dimensional variational assimilation of ozone profiles from the Microwave Limb Sounder on the Aura satellite SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID GENERAL-CIRCULATION MODEL; EOS MLS; PHOTOCHEMISTRY PARAMETERIZATION; STRATOSPHERIC OZONE; TRANSPORT MODEL; SYSTEM; VALIDATION; IMPACT; WAVES AB Ozone profiles from the Microwave Limb Sounder (MLS) onboard the Aura satellite of the NASA's Earth Observing System (EOS) were experimentally added to the European Centre for Medium-range Weather Forecasts (ECMWF) four-dimensional variational (4D-var) data assimilation system of version CY30R1, in which total ozone columns from Scanning Imaging Absorption Spectrometer for Atmospheric CHartographY (SCIAMACHY) onboard the Envisat satellite and partial profiles from the Solar Backscatter Ultraviolet (SBUV/2) instrument onboard the NOAA-16 satellite have been operationally assimilated. As shown by results for the autumn of 2005, additional constraints from MLS data significantly improved the agreement of the analyzed ozone fields with independent observations throughout most of the stratosphere, owing to the daily near-global coverage and good vertical resolution of MLS observations. The largest impacts were seen in the middle and lower stratosphere, where model deficiencies could not be effectively corrected by the operational observations without the additional information on the ozone vertical distribution provided by MLS. Even in the upper stratosphere, where ozone concentrations are mainly determined by rapid chemical processes, dense and vertically resolved MLS data helped reduce the biases related to model deficiencies. These improvements resulted in a more realistic and consistent description of spatial and temporal variations in stratospheric ozone, as demonstrated by cases in the dynamically and chemically active regions. However, combined assimilation of the often discrepant ozone observations might lead to underestimation of tropospheric ozone. In addition, model deficiencies induced large biases in the upper stratosphere in the medium-range (5-day) ozone forecasts. C1 [Feng, Liang; Harwood, R. S.; Filipiak, M. J.] Univ Edinburgh, Inst Atmospher & Environm Sci, Edinburgh EH9 3JN, Midlothian, Scotland. [Brugge, R.; O'Neill, A.] Univ Reading, Data Assimilat Res Ctr, Reading RG6 6BB, Berks, England. [Holm, E. V.] European Ctr Medium Range Weather Forecasts, Reading RG2 9AX, Berks, England. [Froidevaux, L.; Livesey, N.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Feng, L (reprint author), Univ Edinburgh, Inst Atmospher & Environm Sci, Crew Bldg,Kings Bldgs, Edinburgh EH9 3JN, Midlothian, Scotland. EM liang@met.ed.ac.uk NR 45 TC 8 Z9 9 U1 1 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 25 PY 2008 VL 113 IS D15 AR D15S07 DI 10.1029/2007JD009121 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 295FI UT WOS:000255460000002 ER PT J AU Sui, CH Li, X Ho, CH Lau, KM AF Sui, C. -H. Li, X. Ho, C. -H. Lau, K. -M. TI Effects of radiative cooling on the tropical convective response to sea surface temperature: 2-D large domain cumulus ensemble simulations SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID EL-NINO; MESOSCALE PROCESSES; CIRRUS CLOUDS; EQUILIBRIUM; MODEL; GREENHOUSE; WATER; SENSITIVITY; COOLNESS; SYSTEMS AB The effects of radiative cooling on the tropical convective response to sea surface temperature (SST) are investigated using a series of two-dimensional large domain cloud-resolving simulations. The experiments are designed with an imposed warm-pool SST at 2.5 degrees C, 3.5 degrees C, and 4.5 degrees C higher than the cold-pool SST, which is specified at 26 degrees C. The area ratio of the model cold pool to the warm pool is set to 2.2. It is observed that the warm-pool convection intensifies when the SST difference between the warm and cold pools increases from 2.5 degrees C to 3.5 degrees C, whereas the warm-pool convection strength does not significantly change when the SST difference increases from 3.5 degrees C to 4.5 degrees C, which is qualitatively consistent with the observations. The analysis of the atmospheric heat budgets shows that the cap on the development of convection over the warm pool is due to a radiative cooling over the cold pool that has a small variability. The cloud-resolving model simulations indicate that the area of the radiatively driven subsidence expands to produce an enhanced mass exchange between the warm and cold pools in response to the enhanced SST difference between them. This acts against the tendency for increased clouds by the enhanced upward mass flux in response to the warmer SST over the warm pool; significantly stronger SST differences between the two pools (e.g., >= 3.5 degrees C in the cloud-resolving model) do not proportionally produce further intensive convection activities over the warm pool. C1 [Sui, C. -H.] Natl Cent Univ, Inst Hydrol & Ocean Sci, Jhongli 32001, Taoyuan Cty, Taiwan. [Sui, C. -H.] Natl Cent Univ, Dept Atmospher Sci, Jhongli 32001, Taoyuan Cty, Taiwan. [Li, X.] NOAA, NESDIS, Ctr Satellite Applicat & Res, Camp Springs, MD USA. [Ho, C. -H.] Seoul Natl Univ, Sch Earth & Environm Sci, Seoul, South Korea. [Lau, K. -M.] NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. RP Sui, CH (reprint author), Natl Cent Univ, Inst Hydrol & Ocean Sci, 300 Wu Chuan Li, Jhongli 32001, Taoyuan Cty, Taiwan. EM sui@ncu.edu.tw RI Li, Xiaofan/F-5605-2010; Li, Xiaofan/G-2094-2014; Ho, Chang-Hoi/H-8354-2015; Lau, William /E-1510-2012; OI Lau, William /0000-0002-3587-3691; SUI, CHUNG-HSIUNG/0000-0003-2842-5660 NR 35 TC 1 Z9 1 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 25 PY 2008 VL 113 IS D8 AR D08116 DI 10.1029/2007JD008557 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 295FE UT WOS:000255459600002 ER PT J AU Zheng, QN Lin, H Meng, JM Hu, XM Song, YT Zhang, YZ Li, CY AF Zheng, Quanan Lin, Hui Meng, Junmin Hu, Xiaomin Song, Y. Tony Zhang, Yuanzhi Li, Chunyan TI Sub-mesoscale ocean vortex trains in the Luzon Strait SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID SOUTH CHINA SEA; STREETS; WATER; IMAGE AB This study uses the Argos satellite-tracked surface drifter trajectory data and ENVISAT (European satellite) ASAR (advanced synthetic aperture radar) images to illustrate the ocean vortex trains (OVT) in the Luzon Strait. Two cases that occurred in the northwest of Babuyan Island are observed. The first train of three cyclonic vortices showed up on drifter trajectories from 20 degrees to 20.5 degrees N and from 120 degrees to 121 degrees E, and the second, consisting of five pairs of cyclonic-anticyclonic vortices, occurred on the upstream side of the first one from 19.5 degrees to 20.0 degrees N and from 121.0 degrees to 122.0 degrees E and showed up on the ASAR images acquired on 19 November 2006. The total length of the vortex train axis reaches about 250 km. All vortices propagate northwestward (similar to 315 degrees TN). The mean angular velocity is (2.07 +/- 0.18) x 10(-5) s(-1). Theoretical models of ocean vortex radar image derived from radar imaging theories are used to extract dynamical parameters from ASAR imagery signatures, which include the distance between two consecutive vortices and that between two rows of vortices of (22.6 +/- 1.9) km and (8.2 +/- 1.2) km, respectively, the maximum rotational velocity radius as 4.70 km, and the vortex rotational angular velocity 3 x 10(-5)s(-1). Dynamical analyses give the mean velocity of the current of 0.65 ms(-1), and the propagation velocity of the vortex 0.58 ms(-1). The vortex shedding rate is estimated as 2.57 x 10(-5) s(-1). The Reynolds number is estimated as 50 to 500. For the individual vortex and the vortex train, the Rossby numbers are O(0.4), and O(0.5), respectively, implying that both vortex and vortex train observed in the Luzon Strait have a sub-mesoscale nature. This study also reveals a strong current with an average surface current velocity of around 0.7 ms(-1) and the direction of around 315 degrees TN flowing directly from the Pacific to SCS passing through the southern Luzon Strait. The mean flow velocity can be calculated using methods developed in this study and OVT dynamical models. This information may provide more insight to the circulation systems in the area including the origin of Kuroshio. C1 [Zheng, Quanan] Univ Maryland, Dept Atmospher & Ocean Sci, College Pk, MD 20742 USA. [Hu, Xiaomin] State Ocean Adm, Inst Oceanog 1, Key Lab Marine Sci & Numer Modeling, Shandong 266061, Peoples R China. [Li, Chunyan] Louisiana State Univ, Dept Oceanog & Coastal Sci, Coastal Studies Inst, Baton Rouge, LA 70803 USA. [Lin, Hui; Meng, Junmin; Zhang, Yuanzhi] Chinese Univ Hong Kong, Chung Chi Coll, Inst Space & Earth Informat Sci, Sha Tin, Hong Kong, Peoples R China. [Song, Y. Tony] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Zheng, QN (reprint author), Univ Maryland, Dept Atmospher & Ocean Sci, 2423 Comp Space Sci Bldg, College Pk, MD 20742 USA. EM quanan@atmos.umd.edu RI Zheng, Quanan/F-9025-2010 NR 26 TC 15 Z9 17 U1 1 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD APR 25 PY 2008 VL 113 IS C4 AR C04032 DI 10.1029/2007JC004362 PG 12 WC Oceanography SC Oceanography GA 295FQ UT WOS:000255460800002 ER PT J AU Van Snyder, W AF Van Snyder, W. TI The benefits of posing application software as a language interpreter SO SOFTWARE-PRACTICE & EXPERIENCE LA English DT Article DE mathematical software; Fortran; scientific software; real-time systems; operating systems AB Complicated and comprehensive software that is meant to execute in a non-interactive or semi-interactive mode needs to be configured to carry out the desired tasks, needs to carry out those tasks efficiently, needs to be extensible to take on additional ambitions, and needs to be maintainable. To reduce costs, it is helpful if experts in the discipline to which the program applies can configure and operate the program without needing to become expert software engineers and without needing to become familiar with the internal details of the program, and if software engineers who develop and maintain the program need not become experts in its target discipline. Progress toward these goals can be advanced by posing the software as a language interpreter. We describe the application of this principle to ground-based data analysis software for the Microwave Limb Sounder instrument on the NASA Earth Observing System Aura satellite, but we believe the principle has substantially broader applicability. Copyright (C) 2007 John Wiley & Sons, Ltd. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Van Snyder, W (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,Mail Stop 183-701, Pasadena, CA 91109 USA. EM van.snyder@jpl.nasa.gov NR 5 TC 0 Z9 0 U1 0 U2 0 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0038-0644 J9 SOFTWARE PRACT EXPER JI Softw.-Pract. Exp. PD APR 25 PY 2008 VL 38 IS 5 BP 509 EP 522 DI 10.1002/spe.845 PG 14 WC Computer Science, Software Engineering SC Computer Science GA 289YR UT WOS:000255090300004 ER PT J AU Terada, Y Hayashi, T Ishida, M Mukai, K Dotani, T Okada, S Nakamura, R Naik, S Bamba, A Makishima, K AF Terada, Yukikatsu Hayashi, Takayuki Ishida, Manabu Mukai, Koji Dotani, Tadayasu Okada, Shunsaku Nakamura, Ryoko Naik, Sachindra Bamba, Aya Makishima, Kazuo TI Suzaku discovery of hard X-ray pulsations from a rotating magnetized white dwarf, AE Aquarii SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN LA English DT Article DE acceleration of particles; stars : white dwarfs; X-rays : individual (AE Aquarii) ID TEV GAMMA-RAYS; CATACLYSMIC VARIABLES; RADIO-EMISSION; BOARD SUZAKU; AM HERCULIS; PARTICLE-ACCELERATION; HOT PLASMA; DIAGNOSTICS; LUMINOSITY; PROPELLER AB A fast rotating magnetized white dwarf, AE Aquarii, was observed with Suzaku, in 2005 October-November and 2006 October with exposures of 53.1 and 42.4ks, respectively. In addition to clear spin modulation in the 0.5-10 keV band of the XIS data at the barycentric period of 33.0769 +/- 0.0001 s, the 10-30 keV HXD data in the second half of the 2005 observation also showed statistically significant periodic signals at a consistent period. On that occasion, the spin-folded HXD light curve exhibited two sharp spikes separated by similar to 0.2 cycles in phase, in contrast to approximately sinusoidal profiles observed at energies below similar to 4 keV. The folded 4-10 keV XIS light curves are understood to be a superposition of those two types of pulse profiles. The phase-averaged 1.5-10 keV spectra can be reproduced by two thermal components with temperatures of 2.0(-0.16)(+0.20) keV and 0.53(-0.13)(+0.14) keV but the 12-25 keV HXD data show a significant excess above the extrapolated model. This excess can be explained by either a power-law model with a photon index of 1.12(-0.62)(+0.63) or a third thermal component with a temperature of 54(-47)(+26) keV. At a distance of 102pc, the 4-30keV luminosities of the thermal and the additional components become 1.7(-0.6)(+1.3) and 5.3(-0.3)(+15.3) X 10(29) erg s(-1), respectively. The latter corresponds to 0.09% of the spin-down energy of the object. Possible emission mechanisms of the hard pulsations are discussed, including non-thermal ones, in particular. C1 [Terada, Yukikatsu] Saitama Univ, Dept Phys Sci, Saitama 3388570, Japan. [Hayashi, Takayuki] Tokyo Metroporitan Univ, Dept Phys, Tokyo 1920397, Japan. [Ishida, Manabu; Dotani, Tadayasu; Okada, Shunsaku; Nakamura, Ryoko; Bamba, Aya] Japan Aerosp Explorat Agcy, Inst Space & Astronaut Sci, Dept High Energy Astrophys, Sagamihara, Kanagawa 2298510, Japan. [Mukai, Koji] NASA, Goddard Space Flight Ctr, Explorat Universe Div, Greenbelt, MD 20771 USA. [Naik, Sachindra] Phys Res Lab, Ahmadabad 380009, Gujarat, India. [Makishima, Kazuo] RIKEN, Makishima Cosm Radiat Lab, Wako, Saitama 3510198, Japan. [Makishima, Kazuo] Univ Tokyo, Bunkyo Ku, Grad Sch Sci, Dept Phys, Tokyo 1130033, Japan. RP Terada, Y (reprint author), Saitama Univ, Dept Phys Sci, Saitama 3388570, Japan. EM terada@phy.saitama-u.ac.jp RI Terada, Yukikatsu/A-5879-2013; XRAY, SUZAKU/A-1808-2009 OI Terada, Yukikatsu/0000-0002-2359-1857; NR 50 TC 32 Z9 32 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0004-6264 EI 2053-051X J9 PUBL ASTRON SOC JPN JI Publ. Astron. Soc. Jpn. PD APR 25 PY 2008 VL 60 IS 2 BP 387 EP 397 DI 10.1093/pasj/60.2.387 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 300IV UT WOS:000255818400025 ER PT J AU Keszthelyi, L Jaeger, W McEwen, A Tornabene, L Beyer, RA Dundas, C Milazzo, M AF Keszthelyi, Laszlo Jaeger, Windy McEwen, Alfred Tornabene, Livio Beyer, Ross A. Dundas, Colin Milazzo, Moses TI High Resolution Imaging Science Experiment (HiRISE) images of volcanic terrains from the first 6 months of the Mars Reconnaissance Orbiter Primary Science Phase SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID KILAUEA VOLCANO; GROUND ICE; LAVA FLOWS; MORPHOLOGY; SURFACE; HAWAII; FIELD; EMPLACEMENT; AUSTRALIA; INFLATION AB In the first 6 months of the Mars Reconnaissance Orbiter's Primary Science Phase, the High Resolution Imaging Science Experiment (HiRISE) camera has returned images sampling the diversity of volcanic terrains on Mars. While many of these features were noted in earlier imaging, they are now seen with unprecedented clarity. We find that some volcanic vents produced predominantly effusive products while others generated mostly pyroclastics. Flood lavas were emplaced in both turbulent and gentle eruptions, producing roofed channels and inflation features. However, many areas on Mars are too heavily mantled to allow meter-scale volcanic features to be discerned. In particular, the major volcanic edifices are extensively mantled, though it is possible that some of the mantle is pyroclastic material rather than atmospheric dust. Support imaging by the Context Imager (CTX) and topographic information derived from stereo imaging are both invaluable in interpreting the HiRISE data. C1 [Keszthelyi, Laszlo; Jaeger, Windy; Milazzo, Moses] US Geol Survey, Flagstaff, AZ 86001 USA. [Beyer, Ross A.] SETI Inst, Carl Sagan CTr, Mountain View, CA 94305 USA. [McEwen, Alfred; Tornabene, Livio; Dundas, Colin] Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. [Beyer, Ross A.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Keszthelyi, L (reprint author), US Geol Survey, 2255 N Gemini Dr, Flagstaff, AZ 86001 USA. EM laz@usgs.gov OI Dundas, Colin/0000-0003-2343-7224; Beyer, Ross/0000-0003-4503-3335 NR 65 TC 47 Z9 47 U1 0 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9097 EI 2169-9100 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD APR 24 PY 2008 VL 113 IS E4 AR E04005 DI 10.1029/2007JE002968 PG 25 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 295FS UT WOS:000255461000002 ER PT J AU Voorhies, CV AF Voorhies, Coerte V. TI Thickness of the magnetic crust of Mars SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID SPHERICAL HARMONIC MODEL; POLE POSITIONS; FIELD; ANOMALIES; ATLANTIC; ALTITUDE; OCEAN; EARTH AB To estimate the thickness of the magnetic crust of Mars, six observational magnetic spectra are fitted with the theoretical spectrum expected from a novel, bimodal distribution of magnetic sources. Observational spectra differ, for each comes from a different map or model of variously selected and analyzed Mars Global Surveyor Magnetometer/Electron Reflectometer measurements of the vector magnetic field around Mars. The new theoretical spectrum represents fields from both compact sources and extended, laterally correlated sources on a spherical shell, so the estimated shell depth can now be doubled to obtain layer thickness. This typical magnetic crustal thickness is put at 47.8 +/- 8.4 km. The extensive sources are enormous, typically 650 km across, and account for over half the magnetic energy at low degrees. There is some indication that these sources are relatively shallow, but the typical area remains about 330,000 km(2). Granted such extended sources represent magnetization of Mars' ancient crust in a core source field dominated by a reversing, areocentric paleodipole, each one arguably formed during a single polarity chron. How did such vast regions of magnetic crust form? A survey of many eligible mechanisms suggests magnetization of cooling igneous rock at minimal rates of about 1 to 0.1 km(3)/a during superchrons of order 15 to 150 Ma long. C1 NASA, Goddard Space Flight Ctr, Planetary Geodynam Lab, Greenbelt, MD 20771 USA. RP Voorhies, CV (reprint author), NASA, Goddard Space Flight Ctr, Planetary Geodynam Lab, Mail Code 698,Bldg 33,Room F362, Greenbelt, MD 20771 USA. EM coerte.v.voorhies@nasa.gov RI Voorhies, Coerte/D-4672-2012 NR 50 TC 20 Z9 20 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD APR 24 PY 2008 VL 113 IS E4 AR E04004 DI 10.1029/2007JE002928 PG 17 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 295FS UT WOS:000255461000001 ER PT J AU Huang, FT Mayr, HG Russell, JM Mlynczak, MG Reber, CA AF Huang, Frank T. Mayr, Hans G. Russell, James M., III Mlynczak, Martin G. Reber, Carl A. TI Ozone diurnal variations and mean profiles in the mesosphere, lower thermosphere, and stratosphere, based on measurements from SABER on TIMED SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID WATER-VAPOR; TEMPERATURE CORRELATIONS; UARS; OSCILLATIONS; ATMOSPHERE; MODEL; MLS AB Ozone measurements from SABER on the TIMED satellite form a unique data set. They provide global information over the range of local solar times, from the lower stratosphere into the lower thermosphere, from the beginning of 2002, by one instrument. On the basis of zonal means of these data, we present new results from 20 to 100 km in altitude and from 48 degrees S to 48 degrees N in latitude, of ozone diurnal variations over 24 h in local solar time and over an annual cycle. While some of the results are new for the stratosphere, such comprehensive results for the mesosphere and lower thermosphere have not been available before. The diurnal variations generally become increasingly significant from the upper stratosphere into the lower thermosphere and provide information on the photochemistry of ozone and effects of transport over a diurnal cycle. Over most altitudes in the mesosphere and lower thermosphere (MLT), our estimates show the expected decrease in ozone after sunrise, with smaller variations during the day, and the increase near sunset. Outside of a small altitude near 80 km, the nighttime mixing ratios are generally larger than the daytime values. The diurnal variations themselves appear to exhibit variations over an annual cycle, including semiannual and annual variations. We compare the SABER results with data obtained about 10 years earlier by the MLS instrument on UARS, and with results by others based on data from HRDI on UARS, from the Solar Mesosphere Explorer (SME), from selected space shuttle experiments, and from ground-based measurements. From the middle mesosphere to higher altitudes, departures from local thermodynamic equilibrium (non-LTE) can be significant, and the uncertainties can be larger than those at lower altitudes. C1 [Huang, Frank T.] Creat Comp Solut Inc, Rockville, MD 20850 USA. [Mayr, Hans G.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Mlynczak, Martin G.] NASA, Langley Res Ctr, Hampton, VA 23681 USA. [Reber, Carl A.] Sci & Technol Corp, Hampton, VA 23666 USA. [Russell, James M., III] Hampton Univ, Ctr Atmospher Sci, Hampton, VA 23668 USA. RP Huang, FT (reprint author), Creat Comp Solut Inc, 1901 Res Blvd, Rockville, MD 20850 USA. EM fthuang@comcast.net RI Mlynczak, Martin/K-3396-2012 NR 32 TC 25 Z9 25 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD APR 24 PY 2008 VL 113 IS A4 AR A04307 DI 10.1029/2007JA012739 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 295GA UT WOS:000255461800002 ER PT J AU Meier, DL AF Meier, David L. TI Astrophysics - Exhaust inspection SO NATURE LA English DT Editorial Material ID JETS; OUTFLOWS C1 CALTECH, Jet Prop Lab, NASA, Pasadena, CA 91109 USA. RP Meier, DL (reprint author), CALTECH, Jet Prop Lab, NASA, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM dlm@sgra.jpl.nasa.gov NR 12 TC 1 Z9 1 U1 0 U2 0 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD APR 24 PY 2008 VL 452 IS 7190 BP 945 EP 946 DI 10.1038/452945b PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 291PF UT WOS:000255208600027 PM 18432234 ER PT J AU Johnston, DW McDonald, M Polovina, J Domokos, R Wiggins, S Hildebrand, J AF Johnston, D. W. McDonald, M. Polovina, J. Domokos, R. Wiggins, S. Hildebrand, J. TI Temporal patterns in the acoustic signals of beaked whales at Cross Seamount SO BIOLOGY LETTERS LA English DT Article DE beaked whales; passive acoustic monitoring; seamounts; Pacific Ocean; fisheries acoustics ID COBB SEAMOUNT; PACIFIC; YELLOWFIN; SEA AB Seamounts may influence the distribution of marine mammals through a combination of increased ocean mixing, enhanced local productivity and greater prey availability. To study the effects of seamounts on the presence and acoustic behaviour of cetaceans, we deployed a high-frequency acoustic recording package on the summit of Cross Seamount during April through October 2005. The most frequently detected cetacean vocalizations were echolocation sounds similar to those produced by ziphiid and mesoplodont beaked whales together with buzz-type signals consistent with prey-capture attempts. Beaked whale signals occurred almost entirely at night throughout the six-month deployment. Measurements of prey presence with a Simrad EK-60 fisheries acoustics echo sounder indicate that Cross Seamount may enhance local productivity in near-surface waters. Concentrations of micronekton were aggregated over the seamount in near-surface waters at night, and dense concentrations of nekton were detected across the surface of the summit. Our results suggest that seamounts may provide enhanced foraging opportunities for beaked whales during the night through a combination of increased productivity, vertical migrations by micronekton and local retention of prey. Furthermore, the summit of the seamount may act as a barrier against which whales concentrate prey. C1 [Johnston, D. W.] Univ Hawaii, Joint Inst Marine & Atmospher Res, Honolulu, HI 96822 USA. [McDonald, M.] Whale Acoust, Bellvue, CO 80512 USA. [Polovina, J.; Domokos, R.] Pacific Islands Fisheries Sci Ctr, Natl Marine Fisheries Serv, Honolulu, HI 96822 USA. [Wiggins, S.; Hildebrand, J.] Univ Calif San Diego, Scripps Inst Oceanog, Marine Phys Lab, La Jolla, CA 92093 USA. RP Johnston, DW (reprint author), Univ Hawaii, Joint Inst Marine & Atmospher Res, 1000 Pope Rd,Marine Sci Bldg 312, Honolulu, HI 96822 USA. EM dave.johnston@noaa.gov OI Domokos, Reka/0000-0003-3297-4793 NR 21 TC 31 Z9 32 U1 0 U2 9 PU ROYAL SOC PI LONDON PA 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 1744-9561 J9 BIOL LETTERS JI Biol. Lett. PD APR 23 PY 2008 VL 4 IS 2 BP 208 EP 211 DI 10.1098/rsbl.2007.0614 PG 4 WC Biology; Ecology; Evolutionary Biology SC Life Sciences & Biomedicine - Other Topics; Environmental Sciences & Ecology; Evolutionary Biology GA 279KD UT WOS:000254353200021 PM 18252660 ER PT J AU Fan, JW Zhang, RY Tao, WK Mohr, KI AF Fan, Jiwen Zhang, Renyi Tao, Wei-Kuo Mohr, Karen I. TI Effects of aerosol optical properties on deep convective clouds and radiative forcing SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ATMOSPHERIC AEROSOLS; MODEL SIMULATIONS; BOUNDARY-LAYER; ORGANIC-ACIDS; INDIAN-OCEAN; CLIMATE; URBAN; PARAMETERIZATION; MICROPHYSICS; POLLUTION AB The aerosol radiative effects (ARE) on the deep convective clouds are investigated by using a spectral-bin cloud-resolving model coupled with a radiation scheme and an explicit land surface model. The sensitivity of cloud properties and the associated radiative forcing to aerosol single-scattering albedo (SSA) are examined. The ARE on cloud properties is pronounced for mid-visible SSA of 0.85. Relative to the case without ARE, the cloud fraction and optical depth decrease by about 18% and 20%, respectively. Ice particle number concentrations, liquid water path, ice water path, and droplet size decrease by more than 15% when the ARE is introduced. The ARE causes a surface cooling of about 0.35 K and significantly high heating rates in the lower troposphere (about 0.6 K day(-1) higher at 2 km), both of which lead to a more stable atmosphere and hence weaker convection. The weaker convection explains the less cloudiness, lower cloud optical depth, less LWP and IWP, smaller droplet size, and less precipitation resulting from the ARE. The daytime-mean direct forcing induced by black carbon is about 2.2 W m(-2) at the top of atmosphere (TOA) and -17.4 W m(-2) at the surface for SSA of 0.85. The semi-direct forcing is positive, about 10 and 11.2 W m(-2) at the TOA and surface, respectively. Both the TOA and surface total radiative forcing values are strongly negative for the deep convective clouds, attributed mostly to aerosol indirect forcing. Aerosol direct and semi- direct effects are very sensitive to SSA when aerosol optical depth is high. Because the positive semi- direct forcing compensates the negative direct forcing at the surface, the surface temperature and heat fluxes decrease less significantly with the increase of aerosol absorption (decreasing SSA). The cloud fraction, optical depth, convective strength, and precipitation decrease with the increase of absorption, resulting from a more stable atmosphere due to enhanced surface cooling and atmospheric heating. C1 [Fan, Jiwen; Zhang, Renyi] Texas A&M Univ, Dept Atmospher Sci, College Stn, TX 77843 USA. [Tao, Wei-Kuo] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Mohr, Karen I.] SUNY Albany, Dept Earth & Atmospher Sci, Albany, NY 12222 USA. RP Fan, JW (reprint author), Pacific NW Natl Lab, POB 999,MSIN K9-24, Richland, WA 99352 USA. EM renyi-zhang@neo.tamu.edu RI Zhang, Renyi/A-2942-2011; Fan, Jiwen/E-9138-2011; Mohr, Karen/E-4331-2012 NR 64 TC 71 Z9 73 U1 5 U2 25 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 23 PY 2008 VL 113 IS D8 AR D08209 DI 10.1029/2007JD009257 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 295FC UT WOS:000255459400004 ER PT J AU Ewing, SA Macalady, JL Warren-Rhodes, K McKay, CP Amundson, R AF Ewing, S. A. Macalady, J. L. Warren-Rhodes, K. McKay, C. P. Amundson, R. TI Changes in the soil C cycle at the arid-hyperarid transition in the Atacama Desert SO JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES LA English DT Article ID EASTERN MOJAVE DESERT; CARBON-ISOTOPE RATIOS; NORTHERN CHILE; ORGANIC-MATTER; CLIMATE; VEGETATION; CALIFORNIA; FRACTIONATION; DELTA-C-13; DYNAMICS AB We examined soil organic C (OC) turnover and transport across the rainfall transition from a biotic, arid site to a largely abiotic, hyperarid site. With this transition, OC concentrations decrease, and C cycling slows precipitously, both in surface horizons and below ground. The concentration and isotopic character of soil OC across this transition reflect decreasing rates of inputs, decomposition, and downward transport. OC concentrations in the arid soil increase slightly with depth in the upper meter, but are generally low and variable (similar to 0.05%; total inventory of 1.82 kg m(-2)); OC-Delta(14)C values decrease from modern (+ 7 parts per thousand) to very (14)C-depleted (similar to 966 parts per thousand) with depth; and OC-delta(13)C values are variable (-23.7 parts per thousand to -14.1 parts per thousand). Using a transport model, we show that these trends reflect relatively rapid cycling in the upper few centimeters, and spatially variable preservation of belowground OC from root inputs, possibly during a previous, wetter climate supporting higher soil OC concentrations. In the driest soil, the OC inventory is the lowest among the sites (0.19 kg m(-2)), and radiocarbon values are (14)C-depleted (-365 parts per thousand to -696 parts per thousand) but show no trend with depth, indicating belowground OC inputs and long OC residence times throughout the upper meter (10(4) y). A distinct depth trend in delta(13) C values and OC/ON values within the upper 40 cm at the driest site may reflect photochemical alteration of organic matter at the soil surface, combined with limited subsurface decomposition and downward transport. We argue that while root inputs are preserved at the wetter sites, C cycling in the most hyperarid soil occurs through infrequent, rapid dissolved transport of highly photodegraded organic matter during rare rain events, each followed by a pulse of decomposition and subsequent prolonged drought. These belowground inputs are likely a primary control on the character, activity, and depth distribution of small microbial populations. While the lack of water is the dominant control on C cycling, very low C/N ratios of organic matter suggest that when rainfall occurs, hyperarid soils are effectively C limited. The preservation of fossil root fragments in the sediment beneath the driest soil indicates that wetter climate conditions preceded formation of this soil, and that vadose zone microbial activity has been extremely limited for the past 2 My. C1 [Ewing, S. A.; Amundson, R.] Univ Calif Berkeley, ESPM, Ecosyst Sci Div, Berkeley, CA 94720 USA. [Macalady, J. L.] Penn State Univ, Dept Geosci, University Pk, PA 16802 USA. [Warren-Rhodes, K.; McKay, C. P.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Ewing, SA (reprint author), US Geol Survey, 3215 Marine St,Suite E-127, Boulder, CO 80303 USA. EM saewing@usgs.gov RI Amundson, Ronald /E-2654-2015 NR 35 TC 14 Z9 14 U1 3 U2 18 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-BIOGEO JI J. Geophys. Res.-Biogeosci. PD APR 23 PY 2008 VL 113 IS G2 AR G02S90 DI 10.1029/2007JG000495 PG 16 WC Environmental Sciences; Geosciences, Multidisciplinary SC Environmental Sciences & Ecology; Geology GA 295FJ UT WOS:000255460100001 ER PT J AU Cook, BI Miller, RL Seager, R AF Cook, Benjamin I. Miller, Ron L. Seager, Richard TI Dust and sea surface temperature forcing of the 1930s "Dust Bowl" drought SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID PRECIPITATION; AEROSOLS; VARIABILITY; SIMULATIONS AB Droughts over the central United States (US) are modulated by sea surface temperature (SST) variations in the eastern tropical Pacific. Many models, however, are unable to reproduce the severity and spatial pattern of the "Dust Bowl'' drought of the 1930s with SST forcing alone. We force an atmosphere general circulation model with 1930s SSTs and model-generated dust emission from the Great Plains region. The SSTs alone force a drought over the US similar to observations, but with a weaker precipitation anomaly that is centered too far south. Inclusion of dust radiative forcing, centered over the area of observed wind erosion, increases the intensity of the drought and shifts its center northward. While our conclusions are tempered by limited quantitative observations of the dust aerosol load and soil erosion during this period, our study suggests that unprecedented atmospheric dust loading over the continental US exacerbated the "Dust Bowl'' drought. C1 [Cook, Benjamin I.; Miller, Ron L.] NASA, Goddard Inst Space Studies, New York, NY 10025 USA. [Seager, Richard] Lamont Doherty Earth Observ, Palisades, NY 10964 USA. RP Cook, BI (reprint author), NASA, Goddard Inst Space Studies, 2880 Broadway, New York, NY 10025 USA. EM bc9z@ldeo.columbia.edu RI Miller, Ron/E-1902-2012; Cook, Benjamin/H-2265-2012; Bindoff, Nathaniel/C-8050-2011 OI Bindoff, Nathaniel/0000-0001-5662-9519 NR 27 TC 27 Z9 27 U1 7 U2 26 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 EI 1944-8007 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR 22 PY 2008 VL 35 IS 8 AR L08710 DI 10.1029/2008GL033486 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 295ES UT WOS:000255458400006 ER PT J AU Alexandrov, MD Lacis, AA Carlson, BE Cairns, B AF Alexandrov, Mikhail D. Lacis, Andrew A. Carlson, Barbara E. Cairns, Brian TI Characterization of atmospheric aerosols using MFRSR measurements SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ROTATING SHADOWBAND RADIOMETER; SKY RADIANCE MEASUREMENTS; RADIATION MEASUREMENT; OPTICAL-PROPERTIES; NITROGEN-DIOXIDE; TROPOSPHERIC NO2; SUN PHOTOMETERS; TRACE GASES; NETWORK; INSTRUMENT AB [1] Measurements by multifilter rotating shadowband radiometers ( MFRSRs) constitute a valuable global data set with contributions from hundreds of instruments deployed worldwide. The geographical coverage of MFRSR networks is complementary to that of AERONET and often provides better spatial density of measurement sites, especially in the United States. We describe our recently updated analysis algorithm for MFRSR data that allows partitioning of the spectral aerosol optical depth ( AOD) into fine and coarse mode AOD and retrieval of the fine mode effective radius. Our recent sensitivity study demonstrated that for a typical measurement accuracy 0.01 of AOD, the trade-offs between the spectral aerosol extinction and NO2 absorption in the visible range effectively prevent unambiguous retrieval of NO2 column from MFRSR data and may also bias aerosol size distribution retrievals. This has prompted us to adopt a new retrieval approach, which utilizes climatological NO2 ( based on SCIAMACHY satellite retrievals) and uses column ozone from TOMS measurements. The performance of this new approach was evaluated using the long-term data set from the Southern Great Plains ( SGP) site operated by the U. S. Department of Energy Atmospheric Radiation Measurement ( ARM) Program. We present a detailed intercomparison of total, fine, and coarse mode AOD and fine mode effective radius between two MFRSRs located at the SGP's Central Facility and with the correlative AERONET Sun-sky inversion results ( Version 2) derived from a collocated CIMEL Sun photometer. The comparison between two MFRSRs demonstrated good consistency of both the measurements and the analysis. Agreement with AERONET inversions is remarkably good, in that differences in AOD components do not exceed the expected measurement accuracy of 0.01, while the retrieved values of fine mode effective radius show no relative bias and only 0.03 mu m random error ( standard deviation of the differences). We show that if only data with large enough AOD ( more than 0.06 at 870 nm) are selected, this error is reduced by a factor of two, becoming about 10% of a typical fine mode effective radius value. C1 [Alexandrov, Mikhail D.; Cairns, Brian] Columbia Univ, Dept Appl Phys & Appl Math, New York, NY 10027 USA. [Alexandrov, Mikhail D.; Lacis, Andrew A.; Carlson, Barbara E.; Cairns, Brian] NASA, Goddard Inst Space Studies, New York, NY 10025 USA. RP Alexandrov, MD (reprint author), Columbia Univ, Dept Appl Phys & Appl Math, New York, NY 10027 USA. RI Lacis, Andrew/D-4658-2012; Carlson, Barbara/D-8319-2012; OI Cairns, Brian/0000-0002-1980-1022 NR 43 TC 21 Z9 21 U1 0 U2 16 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 22 PY 2008 VL 113 IS D8 AR D08204 DI 10.1029/2007JD009388 PG 23 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 295FB UT WOS:000255459300009 ER PT J AU Shephard, MW Worden, HM Cady-Pereira, KE Lampel, M Luo, MZ Bowman, KW Sarkissian, E Beer, R Rider, DM Tobin, DC Revercomb, HE Fisher, BM Tremblay, D Clough, SA Osterman, GB Gunson, M AF Shephard, Mark W. Worden, Helen M. Cady-Pereira, Karen E. Lampel, Michael Luo, Mingzhao Bowman, Kevin W. Sarkissian, Edwin Beer, Reinhard Rider, David M. Tobin, David C. Revercomb, Henry E. Fisher, Brendan M. Tremblay, Denis Clough, Shepard A. Osterman, Gregory B. Gunson, Michael TI Tropospheric Emission Spectrometer nadir spectral radiance comparisons SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID AURA MISSION; INTERFEROMETER; CALIBRATION; OBJECTIVES; SATELLITE; SYSTEMS; DESIGN; TES AB The fundamental measurement of the Tropospheric Emission Spectrometer (TES) on board the Aura spacecraft is upwelling infrared spectral radiances. Accurate TES retrievals of surface and atmospheric parameters such as trace gas amounts critically depend on well-calibrated radiance spectra. On-orbit TES nadir observations were evaluated using carefully selected, nearly coincident spectral radiance measurements from Atmospheric Infrared Sounder (AIRS) on Aqua and special scanning high-resolution interferometer sounder (SHIS) underflights. Modifications to the L1B calibration algorithms for TES version 2 data resulted in significant improvements for the TES-AIRS comparisons. The comparison of TES with SHIS (adjusted for geometric differences) show mean and standard deviation differences of less than 0.3 K at warmer brightness temperatures of 290-295 K. The TES/SHIS differences are less than 0.4 K at brightness temperatures of 265-270 K. There are larger TES/SHIS comparison differences for higher-frequency TES 1A1 filter, which has less upwelling radiance signal. The TES/AIRS comparisons show mean differences of less than 0.3 K at 290-295 K and less than 0.5 K at 265-270 K with standard deviation less than 0.6 K for the majority of the spectral regions and brightness temperature range. A procedure to warm up the optical bench for better alignment in December 2005 gave a fourfold increase in the signal-to-noise ratio at higher frequency ranges. Recent results from a long-term comparison of TES sea surface temperature (SST) observations with the Reynolds optimally interpolated (ROI) SST product demonstrates TES radiometric stability. C1 [Shephard, Mark W.; Cady-Pereira, Karen E.; Clough, Shepard A.] Atmospher & Environm Res Inc, Lexington, MA 02421 USA. [Worden, Helen M.; Luo, Mingzhao; Bowman, Kevin W.; Sarkissian, Edwin; Beer, Reinhard; Rider, David M.; Fisher, Brendan M.; Osterman, Gregory B.; Gunson, Michael] Jet Prop Lab, Pasadena, CA 91109 USA. [Lampel, Michael; Tremblay, Denis] Raytheon Tech Serv Co, Pasadena, CA 91101 USA. [Tobin, David C.; Revercomb, Henry E.] Univ Wisconsin, Madison, WI 53706 USA. RP Shephard, MW (reprint author), Atmospher & Environm Res Inc, 131 Hartwell Ave, Lexington, MA 02421 USA. EM mshephar@aer.com NR 25 TC 21 Z9 21 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 22 PY 2008 VL 113 IS D15 AR D15S05 DI 10.1029/2007JD008856 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 295FH UT WOS:000255459900001 ER PT J AU Yu, HB Remer, LA Chin, M Bian, HS Kleidman, RG Diehl, T AF Yu, Hongbin Remer, Lorraine A. Chin, Mian Bian, Huisheng Kleidman, Richard G. Diehl, Thomas TI A satellite-based assessment of transpacific transport of pollution aerosol SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Review ID GLOBAL-MODEL GOCART; ART. NO. 4804; AIR-POLLUTION; ACE-ASIA; UNITED-STATES; NORTH-AMERICA; EAST-ASIA; ANTHROPOGENIC AEROSOLS; TROPOSPHERIC AEROSOL; CONTINENTAL OUTFLOW AB It has been well documented that pollution and dust from east Asia can be transported across the North Pacific basin, reaching North America and beyond. In this study, we assess the transpacific transport of "pollution aerosol'' (defined as a mixture of aerosols from urban/industrial pollution and biomass burning) by taking advantage of the much improved measurement accuracy and enhanced new capabilities of satellite sensors in recent years. A 4-year (2002 to 2005) climatology of optical depth for pollution aerosol was generated from Moderate Resolution Imaging Spectroradiometer (MODIS) observations of fine-and coarse-mode aerosol optical depths. The pollution aerosol mass loading and fluxes were then calculated using measurements of the dependence of aerosol mass extinction efficiency on relative humidity and of aerosol vertical distributions from field campaigns and available satellite observations in the region. We estimated that about 18 Tg/a pollution aerosol is exported from east Asia to the northwestern Pacific Ocean, of which about 25% reaches the west coast of North America. The imported flux of 4.4 Tg/a to North America is equivalent to about 15% of local emissions from the United States and Canada. The pollution fluxes are largest in spring and smallest in summer. For the period we have examined the strongest export and import of pollution particulates occurred in 2003, largely because of record intense Eurasia boreal forest fires in spring and summer. The overall uncertainty of pollution fluxes is estimated at a factor of 2. Simulations by the Goddard Chemistry Aerosol Radiation and Transport (GOCART) and Global Modeling Initiative (GMI) models agree quite well with the satellite-based estimates of annual and latitude-integrated fluxes, with larger model-satellite differences in latitudinal and seasonal variations of fluxes. C1 [Yu, Hongbin; Bian, Huisheng; Diehl, Thomas] Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. [Yu, Hongbin; Remer, Lorraine A.; Chin, Mian; Bian, Huisheng; Kleidman, Richard G.; Diehl, Thomas] NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. [Kleidman, Richard G.] Sci Syst & Applicat Inc, Lanham, MD USA. RP Yu, HB (reprint author), Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. EM hongbin.yu@nasa.gov RI Yu, Hongbin/C-6485-2008; Chin, Mian/J-8354-2012 OI Yu, Hongbin/0000-0003-4706-1575; NR 112 TC 62 Z9 62 U1 2 U2 29 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 22 PY 2008 VL 113 IS D14 AR D14S12 DI 10.1029/2007JD009349 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 295FF UT WOS:000255459700001 ER PT J AU Yen, AS Morris, RV Clark, BC Gellert, R Knudson, AT Squyres, S Mittlefehldt, DW Ming, DW Arvidson, R Mccoy, T Schmidt, M Hurowitz, J Li, R Johnson, JR AF Yen, A. S. Morris, R. V. Clark, B. C. Gellert, R. Knudson, A. T. Squyres, S. Mittlefehldt, D. W. Ming, D. W. Arvidson, R. McCoy, T. Schmidt, M. Hurowitz, J. Li, R. Johnson, J. R. TI Hydrothermal processes at Gusev Crater: An evaluation of Paso Robles class soils SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID MARS EXPLORATION ROVERS; MERIDIANI-PLANUM; MOSSBAUER SPECTROMETER; LANDING SITES; IRON MOUNTAIN; SULFATE SALTS; SPIRIT ROVER; MINERALOGY; VOLCANO; CALIFORNIA AB The Mars Exploration Rover Spirit analyzed multiple occurrences of sulfur-rich, light-toned soils along its traverse within Gusev Crater. These hydrated deposits are not readily apparent in images of undisturbed soil but are present at shallow depths and were exposed by the actions of the rover wheels. Referred to as "Paso Robles'' class soils, they are dominated by ferric iron sulfates, silica, and Mg-sulfates. Ca-sulfates, Ca-phosphates, and other minor phases are also indicated in certain specific samples. The chemical compositions are highly variable over both centimeter-scale distances and between the widely separated exposures, but they clearly reflect the elemental signatures of nearby rocks. The quantity of typical basaltic soil mixed into the light-toned materials prior to excavation by the rover wheels is minimal, suggesting negligible reworking of the deposits after their initial formation. The mineralogy, geochemistry, variability, association with local compositions, and geologic setting of the deposits suggest that Paso Robles class soils likely formed as hydrothermal and fumarolic condensates derived from magma degassing and/or oxidative alteration of crustal iron sulfide deposits. Their occurrence as unconsolidated, near-surface soils permits, though does not require, an age that is significantly younger than that of the surrounding rocks. C1 [Yen, A. S.; Hurowitz, J.] CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA. [Morris, R. V.; Mittlefehldt, D. W.; Ming, D. W.] NASA, Johnson Space Ctr, Houston, TX USA. [Clark, B. C.] Lockheed Martin Corp, Littleton, CO USA. [Gellert, R.] Univ Guelph, Dept Phys, Guelph, ON N1G 2W1, Canada. [Knudson, A. T.] Arizona State Univ, Dept Earth & Planetary Sci, Tempe, AZ USA. [Squyres, S.] Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. [Arvidson, R.] Washington Univ, Dept Earth & Planetary Sci, St Louis, MO 63130 USA. [McCoy, T.; Schmidt, M.] Smithsonian Inst, Natl Museum Nat History, Washington, DC USA. [Li, R.] Ohio State Univ, Ctr Mapping, Columbus, OH 43210 USA. [Johnson, J. R.] US Geol Survey, Flagstaff, AZ USA. RP Yen, AS (reprint author), CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA. RI Johnson, Jeffrey/F-3972-2015 NR 61 TC 76 Z9 76 U1 4 U2 17 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9097 EI 2169-9100 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD APR 22 PY 2008 VL 113 IS E6 AR E06S10 DI 10.1029/2007JE002978 PG 19 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 295FT UT WOS:000255461100001 ER PT J AU Scott, KS Austermann, JE Perera, TA Wilson, GW Aretxaga, I Bock, JJ Hughes, DH Kang, Y Kim, S Mauskopf, PD Sanders, DB Scoville, N Yun, MS AF Scott, K. S. Austermann, J. E. Perera, T. A. Wilson, G. W. Aretxaga, I. Bock, J. J. Hughes, D. H. Kang, Y. Kim, S. Mauskopf, P. D. Sanders, D. B. Scoville, N. Yun, M. S. TI AzTEC millimetre survey of the COSMOS field - I. Data reduction and source catalogue SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE galaxies : high-redshift; galaxies : starburst; submillimetre ID DEGREE EXTRAGALACTIC SURVEY; SCUBA SUPER-MAP; SUBMILLIMETER GALAXY POPULATION; NUMBER COUNTS; STAR-FORMATION; HIGH-REDSHIFT; LOCKMAN HOLE; TELESCOPE; EVOLUTION; BOLOCAM AB We present a 1.1 mm wavelength imaging survey covering 0.3 deg(2) in the COSMOS field. These data, obtained with the AzTEC continuum camera on the James Clerk Maxwell Telescope, were centred on a prominent large-scale structure overdensity which includes a rich X-ray cluster at z approximate to 0.73. A total of 50 mm-galaxy candidates, with a significance ranging from 3.5 to 8.5 sigma, are extracted from the central 0.15 deg(2) area which has a uniform sensitivity of similar to 1.3 mJy beam(-1). 16 sources are detected with S/N >= 4.5, where the expected false-detection rate is zero, of which a surprisingly large number (9) have intrinsic (deboosted) fluxes >= 5 mJy at 1.1 mm. Assuming the emission is dominated by radiation from dust, heated by a massive population of young, optically obscured stars, then these bright AzTEC sources have far-infrared luminosities > 6 x 10(12) L-circle dot and star formation rates > 1100 M-circle dot yr(-1). Two of these nine bright AzTEC sources are found towards the extreme peripheral region of the X-ray cluster, whilst the remainder are distributed across the larger scale overdensity. We describe the AzTEC data reduction pipeline, the source-extraction algorithm, and the characterization of the source catalogue, including the completeness, flux deboosting correction, false-detection rate and the source positional uncertainty, through an extensive set of Monte Carlo simulations. We conclude with a preliminary comparison, via a stacked analysis, of the overlapping MIPS 24-mu m data and radio data with this AzTEC map of the COSMOS field. C1 [Scott, K. S.; Austermann, J. E.; Perera, T. A.; Wilson, G. W.; Yun, M. S.] Univ Massachusetts, Dept Astron, Amherst, MA 01003 USA. [Aretxaga, I.; Hughes, D. H.] Inst Nacl Astrofis Opt & Electr, Puebla, Mexico. [Bock, J. J.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Kang, Y.; Kim, S.] Sejong Univ, Dept Astron & Space Sci, Seoul, South Korea. [Mauskopf, P. D.] Cardiff Univ, Cardiff, S Glam, Wales. [Sanders, D. B.] Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA. [Scoville, N.] CALTECH, Pasadena, CA 91125 USA. RP Scott, KS (reprint author), Univ Massachusetts, Dept Astron, Amherst, MA 01003 USA. EM kscott@astro.umass.edu NR 39 TC 133 Z9 133 U1 0 U2 2 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0035-8711 EI 1365-2966 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD APR 21 PY 2008 VL 385 IS 4 BP 2225 EP 2238 DI 10.1111/j.1365-2966.2008.12989.x PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 290SI UT WOS:000255142100048 ER PT J AU Bailey, SW Hooker, SB Antoine, D Franz, BA Werdell, PJ AF Bailey, Sean W. Hooker, Stanford B. Antoine, David Franz, Bryan A. Werdell, P. Jeremy TI Sources and assumptions for the vicarious calibration of ocean color satellite observations SO APPLIED OPTICS LA English DT Article ID WATER-LEAVING RADIANCE; ATMOSPHERIC CORRECTION; SPECTRAL REFLECTANCE; ABOVE-WATER; VALIDATION; SEAWIFS; ORBIT; WHITECAPS; ALGORITHM; SENSORS AB Spaceborne ocean color sensors require vicarious calibration to sea-truth data to achieve accurate water-leaving radiance retrievals. The assumed requirements of an in situ data set necessary to achieve accurate vicarious calibration were set forth in a series of papers and reports developed nearly a decade ago, which were embodied in the development and site location of the Marine Optical BuoY (MOBY). Since that time, NASA has successfully used data collected by MOBY as the sole source of sea-truth data for vicarious calibration of the Sea-viewing Wide field-of-view Sensor (SeaWiFS) and Moderate Resolution Imaging Spectroradiometer instruments. In this paper, we make use of the 10-year, global time series of SeaWiFS measurements to test the sensitivity of vicarious calibration to the assumptions inherent in the in situ requirements (e.g., very low chlorophyll waters, hyperspectral measurements). Our study utilized field measurements from a variety of sources with sufficient diversity in data collection methods and geophysical variability to challenge those in situ restrictions. We found that some requirements could be relaxed without compromising the ability to vicariously calibrate to the level required for accurate water-leaving radiance retrievals from satellite-based sensors. (C) 2008 Optical Society of America. C1 [Bailey, Sean W.; Franz, Bryan A.; Werdell, P. Jeremy] NASA, Goddard Space Flight Ctr, Ocean Biol Proc Grp 614 8, Greenbelt, MD 20771 USA. [Bailey, Sean W.] Futuretech Corp, Greenbelt, MD 20770 USA. [Antoine, David] OOV, LOV, F-06238 Villefranche Sur Mer, France. [Franz, Bryan A.] SAIC Inc, Beltsville, MD 20705 USA. [Werdell, P. Jeremy] Sci Syst & Applicat Inc, Lanham, MD 20706 USA. RP Bailey, SW (reprint author), NASA, Goddard Space Flight Ctr, Ocean Biol Proc Grp 614 8, Greenbelt, MD 20771 USA. EM Sean.W.Bailey@nasa.gov RI Franz, Bryan/D-6284-2012; Werdell, Jeremy/D-8265-2012; Hooker, Stanford/E-2162-2012; Antoine, David/C-3817-2013; Bailey, Sean/D-3077-2017 OI Franz, Bryan/0000-0003-0293-2082; Antoine, David/0000-0002-9082-2395; Bailey, Sean/0000-0001-8339-9763 NR 42 TC 27 Z9 27 U1 0 U2 6 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD APR 20 PY 2008 VL 47 IS 12 BP 2035 EP 2045 DI 10.1364/AO.47.002035 PG 11 WC Optics SC Optics GA 299NI UT WOS:000255761900011 PM 18425176 ER PT J AU Satyapal, S Vega, D Dudik, RP Abel, NP Heckman, T AF Satyapal, S. Vega, D. Dudik, R. P. Abel, N. P. Heckman, T. TI Spitzer uncovers active galactic nuclei missed by optical surveys in seven late-type galaxies SO ASTROPHYSICAL JOURNAL LA English DT Article DE black hole physics; dark matter; galaxies : active; galaxies : spiral; infrared : galaxies ID ULTRALUMINOUS INFRARED GALAXIES; RADIO-CONTINUUM EMISSION; SUPERMASSIVE BLACK-HOLES; NORMAL SPIRAL GALAXIES; SPACE-TELESCOPE; NEARBY GALAXIES; LINER GALAXIES; STAR-FORMATION; HOST GALAXIES; IONIZED-GAS AB We report the discovery using Spitzer's high-resolution spectrograph of seven active galactic nuclei (AGNs) in a sample of 32 late-type galaxies that show no definitive signatures of AGNs in their optical spectra. These observations suggest that the AGN detection rate in late-type galaxies is possibly 4 times larger than what optical spectroscopic observations alone suggest. We demonstrate using photoionization models with an input AGN and an extreme UV -bright starburst ionizing radiation field that the observed mid-infrared line spectrum, which includes the high-ionization [ Ne v] 14 mu m and/ or 24 mu m lines, cannot be replicated unless an AGN contribution, in some cases as little as 10% of the total galaxy luminosity, is included. These models show that when the fraction of the total luminosity due to the AGN is low, optical diagnostics are insensitive to the presence of the AGN. In this regime of parameter space, the mid-infrared diagnostics offer a powerful tool for uncovering AGNs missed by optical spectroscopy. The AGN bolometric luminosities in our sample range from similar to 3 x 10(41) to similar to 2 x 10(43) ergs s(-1), which, based on the Eddington limit, corresponds to a lower mass limit for the black hole that ranges from similar to 3 x 10(3) to as high as similar to 1.5 x 10(5) M-circle dot. These lower mass limits, however, do not put a strain on the well-known relationship between the black hole mass and the host galaxy's stellar velocity dispersion established in predominantly early-type galaxies. Our findings add to the growing evidence that black holes do form and grow in low-bulge environments and that they are significantly more common than optical studies indicate. C1 [Satyapal, S.; Vega, D.; Dudik, R. P.] George Mason Univ, Dept Phys & Astron, Fairfax, VA 22030 USA. [Dudik, R. P.] NASA, Goddard Space Flight Ctr, Observat Cosmol Lab, Greenbelt, MD 20711 USA. [Abel, N. P.] Univ Cincinnati, Dept Phys, Cincinnati, OH 45221 USA. [Heckman, T.] Johns Hopkins Univ, Ctr Astrophys Sci, Dept Phys & Astron, Baltimore, MD 21218 USA. RP Satyapal, S (reprint author), George Mason Univ, Dept Phys & Astron, 4400 Univ Dr,MS 3F3, Fairfax, VA 22030 USA. EM satyapal@physics.gmu.edu NR 85 TC 65 Z9 65 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 2008 VL 677 IS 2 BP 926 EP 942 DI 10.1086/529014 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 287DV UT WOS:000254898000010 ER PT J AU Dey, A Soifer, BT Desai, V Brand, K Le Floc'h, E Brown, MJI Jannuzi, BT Armus, L Bussmann, S Brodwin, M Bian, C Eisenhardt, P Higdon, SJ Weedman, D Willner, SP AF Dey, Arjun Soifer, B. T. Desai, Vandana Brand, Kate Le Floc'h, Emeric Brown, Michael J. I. Jannuzi, Buell T. Armus, Lee Bussmann, Shane Brodwin, Mark Bian, Chao Eisenhardt, Peter Higdon, Sarah J. Weedman, Daniel Willner, S. P. TI A significant population of very luminous dust-obscured galaxies at redshift z similar to 2 SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : formation; galaxies : high-redshift; galaxies : starburst ID SPITZER-SPACE-TELESCOPE; ULTRALUMINOUS INFRARED GALAXIES; DEEP-FIELD-SOUTH; POLYCYCLIC AROMATIC-HYDROCARBON; EXTRAGALACTIC SOURCE COUNTS; STAR-FORMING GALAXIES; KECK-II-TELESCOPE; ARRAY CAMERA IRAC; X-RAY SURVEY; SUBMILLIMETER GALAXIES AB The Spitzer Space Telescope has revealed a significant population of high-redshift (z similar to 2) dust-obscured galaxies with large mid-infrared to ultraviolet luminosity ratios. Due to their optical faintness, these galaxies have been previously missed in traditional optical studies of the distant universe. We present a simple method for selecting this high-redshift population based solely on the ratio of the observed mid-infrared 24 mu m to optical R-band flux density. We apply this method to observations of the approximate to 8.6 deg(2) NOAO Deep Wide-Field Survey Bootes field, and uncover approximate to 2600 dust-obscured galaxy candidates [i. e., 0.089 arcmin(-2)) with 24 mu m flux densities F-24 mu m >= 0.3 mJy and (R-[24]) >= 14 (i. e., F-v(24 mu m)/ F-v(R) >= 1000]. These galaxies have no counterparts in the local universe. They represent 7% +/-0: 6% of the 24 mu m source population at F-24 mu m >= 1 mJy but increase to approximate to 13% +/-1% of the population at approximate to 0.3 mJy. These galaxies exhibit evidence of both star formation and AGN activity, with the brighter 24 mu m sources being more AGN-dominated. We have measured spectroscopic redshifts for 86 of these galaxies, and find a broad redshift distribution centered at (z) over bar approximate to 1.99 +/-0.05. The space density of this population is Sigma(DOG) (F-24 mu m >= 0.3 mJy) (2.82 +/-0.05) x 10(-5)h(70)(3) Mpc(-3), similar to that of bright submillimeter-selected galaxies at comparable redshifts. These redshifts imply large luminosities, with median VLv(8 mu m) approximate to 4 x 10(11) L-circle dot. The infrared luminosity density contributed by this relatively rare dust-obscured galaxy population is log(IRLD) approximate to 8: 23(-0.30)(+0.18). This is approximate to 60(-15)(+40)% of that contributed by z similar to 2 ultraluminous infrared galaxies (ULIRGs, with L-IR > 10(12) L-circle dot); our simple selection thus identifies a significant fraction of z similar to 2 ULIRGs. This IRLD is approximate to 26% +/-14% of the total contributed by all z similar to 2 galaxies. We suggest that these dust-obscured galaxies are the progenitors of luminous (similar to 4L *) present-day galaxies, seen undergoing an extremely luminous, short-lived phase of both bulge and black hole growth. They may represent a brief evolutionary phase between submillimeter-selected galaxies and less obscured quasars or galaxies. C1 [Dey, Arjun; Jannuzi, Buell T.; Brodwin, Mark] Natl Opt Astron Observ, Tucson, AZ 85719 USA. [Soifer, B. T.; Desai, Vandana; Bian, Chao] CALTECH, Caltech Opt Observ, Pasadena, CA 91125 USA. [Soifer, B. T.; Armus, Lee] CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA. [Brand, Kate] Space Telescope Sci Inst, Baltimore, MD 21218 USA. [Le Floc'h, Emeric] Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA. [Brown, Michael J. I.] Monash Univ, Sch Phys, Clayton, Vic 3800, Australia. [Bussmann, Shane] Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. [Eisenhardt, Peter] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Higdon, Sarah J.] Georgia So Univ, Statesboro, GA 30460 USA. [Weedman, Daniel] Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. [Willner, S. P.] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Dey, A (reprint author), Natl Opt Astron Observ, 950 N Cherry Ave, Tucson, AZ 85719 USA. EM dey@noao.edu RI Brown, Michael/B-1181-2015 OI Brown, Michael/0000-0002-1207-9137 NR 76 TC 191 Z9 192 U1 0 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 2008 VL 677 IS 2 BP 943 EP 956 DI 10.1086/529516 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 287DV UT WOS:000254898000011 ER PT J AU Gavazzi, R Treu, T Koopmans, LVE Bolton, AS Moustakas, LA Burles, S Marshall, PJ AF Gavazzi, Raphael Treu, Tommaso Koopmans, Leon V. E. Bolton, Adam S. Moustakas, Leonidas A. Burles, Scott Marshall, Philip J. TI The sloan lens ACS survey. VI. Discovery and analysis of a double Einstein ring SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmological parameters; dark matter; galaxies : elliptical and lenticular; cD; galaxies : halos; galaxies : structure; gravitational lensing ID EARLY-TYPE GALAXIES; DIGITAL SKY SURVEY; DARK-MATTER HALOS; GRAVITATIONAL LENS; INTERNAL STRUCTURE; FUNDAMENTAL PLANE; STELLAR DYNAMICS; DENSITY PROFILE; MASS; IMAGES AB We report the discovery of two concentric Einstein rings around the gravitational lens SDSS J0946+ 1006. The main lens is at redshift z(l) = 0.222, while the inner ring ( 1) is at redshift z(s1) 0.609 (R-Ein1 = 1.43 '' +/- 0.01 ''). The wider image separation ( R-Ein2 = 2.07 '' +/- 0.02 '') of the outer ring (2) implies a higher redshift than that of ring 1; the detection of ring 2 in the F814WACS filter implies an upper limit of z(s2) less than or similar to 6.9. The main lens can be described by a power- law total mass density profile rho(tot) proportional to r(-gamma ') with gamma ' = 2.00 +/- 0.03 and velocity dispersion sigma(SIE) = 287 +/- 5 km s(-1) ( the stellar velocity dispersion is sigma(v,*) = 284 +/- 24 km s(-1)). The strong lensing configuration is inconsistent with light traces mass. Adopting a prior on the stellar mass- to- light ratio from previous SLACS work, we infer a 73% +/- 9% dark matter fraction within the cylinder of radius equal to the effective radius of the lens. We find that, for the case of SDSS J0946+ 1006, the geometry of the two rings does not place interesting constraints on cosmography because of the suboptimal redshifts of lens and sources. We then consider the perturbing effect of the mass associated with ring 1 building a compound lens model. This introduces minor changes to the mass of the main lens and provides an estimate of z(s2) = 3.1(-1.0)(+2.0) and of the mass of the source responsible for ring 1 (sigma(SIE,s1) = 94(-47)(+27) km s(-1)). We conclude by examining the prospects of doing cosmography with a sample of 50 double rings, expected from future space- based surveys. Accounting for uncertainties in the mass profile of the lens and the effects of the perturber, we find that such a sample would constrain Omega(m) and within 10%, assuming flatness. C1 [Gavazzi, Raphael; Treu, Tommaso; Marshall, Philip J.] Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA. [Koopmans, Leon V. E.] Univ Groningen, Kapteyn Astron Inst, NL-9700 AV Groningen, Netherlands. [Bolton, Adam S.] Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA. [Bolton, Adam S.] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. [Moustakas, Leonidas A.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Burles, Scott] MIT, Dept Phys, Cambridge, MA 02139 USA. [Burles, Scott] MIT, Kavli Inst Astrophys & Space Res, Cambridge, MA 02139 USA. RP Gavazzi, R (reprint author), Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA. NR 58 TC 75 Z9 75 U1 1 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 2008 VL 677 IS 2 BP 1046 EP 1059 DI 10.1086/529541 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 287DV UT WOS:000254898000019 ER PT J AU Mukai, K Orio, M Della Valle, M AF Mukai, K. Orio, M. Della Valle, M. TI Novae as a class of transient X-ray sources SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxy : center; novae; cataclysmic variables; X-rays : binaries ID XMM-NEWTON OBSERVATIONS; GALACTIC-CENTER; HERCULIS 1991; V382 VELORUM; CHANDRA OBSERVATIONS; RECURRENT NOVAE; RS-OPHIUCHI; EMISSION; OUTBURST; GALAXY AB Motivated by the recently discovered class of faint (10(34)-10(35) ergs s(-1)) X-ray transients in the Galactic center region, we investigate the 2-10 keV properties of classical and recurrent novae. Existing data are consistent with the idea that all classical novae are transient X-ray sources with durations of months to years and peak luminosities in the 10(34)-10(35) ergs s(-1) range. This makes classical novae a viable candidate class for the faint Galactic center transients. We estimate the rate of classical novae within a 150 radius region centered on the Galactic center ( roughly the field of view of XMM-Newton observations centered on Sgr A*) to be similar to 0.1 yr(-1). Therefore, it is plausible that some of the Galactic center transients that have been announced to date are unrecognized classical novae. The continuing monitoring of the Galactic center region carried out by Chandra and XMM-Newton may therefore provide a new method to detect classical novae in this crowded and obscured region, where optical surveys are not, and can never hope to be, effective. Therefore, X-raymonitoringmay provide the best means of testing the completeness of the current understanding of the nova populations. C1 [Mukai, K.] CRESST, Greenbelt, MD 20771 USA. [Mukai, K.] NASA, Goddard Space Flight Ctr, Xray Astrophys Lab, Greenbelt, MD 20771 USA. [Mukai, K.] Univ Maryland Baltimore Cty, Dept Phys, Baltimore, MD 21250 USA. [Orio, M.] Univ Wisconsin, Dept Astron, Madison, WI 53706 USA. [Orio, M.] Osserv Astron Padova, INAF, I-35122 Padua, Italy. [Orio, M.; Della Valle, M.] Univ Calif Santa Barbara, Kavli Inst Theoret Phys, Santa Barbara, CA 93106 USA. [Della Valle, M.] Osserv Astrofis Arcetri, INAF, I-50125 Florence, Italy. [Della Valle, M.] Int Ctr Relativist Astrophys Network, I-65122 Pescara, Italy. RP Mukai, K (reprint author), CRESST, Greenbelt, MD 20771 USA. EM mukai@milkyway.gsfc.nasa.gov; orio@astro.wisc.edu; massimo@arcetri.astro.it OI Della Valle, Massimo/0000-0003-3142-5020 NR 48 TC 17 Z9 17 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 2008 VL 677 IS 2 BP 1248 EP 1252 DI 10.1086/529362 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 287DV UT WOS:000254898000037 ER PT J AU Barry, RK Danchi, WC Traub, WA Sokoloski, JL Wisniewski, JP Serabyn, E Kuchner, MJ Akeson, R Appleby, E Bell, J Booth, A Brandenburg, H Colavita, M Crawford, S Creech-Eakman, M Dahl, W Felizardo, C Garcia, J Gathright, J Greenhouse, MA Herstein, J Hovland, E Hrynevych, M Koresko, C Ligon, R Mennesson, B Millan-Gabet, R Morrison, D Palmer, D Panteleeva, T Ragland, S Shao, M Smythe, R Summers, K Swain, M Tsubota, K Tyau, C Wetherell, E Wizinowich, P Woillez, J Vasisht, G AF Barry, R. K. Danchi, W. C. Traub, W. A. Sokoloski, J. L. Wisniewski, J. P. Serabyn, E. Kuchner, M. J. Akeson, R. Appleby, E. Bell, J. Booth, A. Brandenburg, H. Colavita, M. Crawford, S. Creech-Eakman, M. Dahl, W. Felizardo, C. Garcia, J. Gathright, J. Greenhouse, M. A. Herstein, J. Hovland, E. Hrynevych, M. Koresko, C. Ligon, R. Mennesson, B. Millan-Gabet, R. Morrison, D. Palmer, D. Panteleeva, T. Ragland, S. Shao, M. Smythe, R. Summers, K. Swain, M. Tsubota, K. Tyau, C. Wetherell, E. Wizinowich, P. Woillez, J. Vasisht, G. TI Milliarcsecond N-band observations of the nova RS Ophiuchi: First science with the Keck Interferometer Nuller SO ASTROPHYSICAL JOURNAL LA English DT Article DE novae, cataclysmic variables; stars : dwarf novae; stars : individual (HD 162214, RS Ophiuchi); techniques : interferometric; techniques : high angular resolution ID SYMBIOTIC STARS; 2006 OUTBURST; BINARY-SYSTEMS; CIRCUMSTELLAR ENVELOPES; ISO OBSERVATIONS; RECURRENT NOVAE; SHOCK-WAVE; SPECTROSCOPY; SUPERNOVAE; ACCRETION AB We report observations of the nova RS Ophiuchi (RS Oph) using the Keck Interferometer Nuller (KIN), approximately 3.8 days following the most recent outburst that occurred on 2006 February 12. These observations represent the first scientific results from the KIN, which operates in N band from 8 to 12.5 mu m in a nulling mode. The nulling technique is the sparse aperture equivalent of the conventional coronagraphic technique used in filled aperture telescopes. In this mode the stellar light itself is suppressed by a destructive fringe, effectively enhancing the contrast of the circumstellar material located near the star. By fitting the unique KIN data, we have obtained an angular size of the mid-infrared continuum emitting material of 6.2, 4.0, or 5.4 mas for a disk profile, Gaussian profile (FWHM), and shell profile, respectively. The data show evidence of enhanced neutral atomic hydrogen emission and atomic metals including silicon located in the inner spatial regime near the white dwarf (WD) relative to the outer regime. There are also nebular emission lines and evidence of hot silicate dust in the outer spatial region, centered at similar to 17 AU from the WD, that are not found in the inner regime. Our evidence suggests that these features have been excited by the nova flash in the outer spatial regime before the blast wave reached these regions. These identifications support a model in which the dust appears to be present between outbursts and is not created during the outburst event. We further discuss the present results in terms of a unifyingmodel of the system that includes an increase in density in the plane of the orbit of the two stars created by a spiral shock wave caused by the motion of the stars through the cool wind of the red giant star. C1 [Barry, R. K.; Danchi, W. C.; Wisniewski, J. P.; Kuchner, M. J.; Greenhouse, M. A.] NASA, Goddard Space Flight Ctr, Exoplanets & Stellar Astrophys Lab, Greenbelt, MD 20771 USA. [Barry, R. K.] Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. [Traub, W. A.; Serabyn, E.; Booth, A.; Colavita, M.; Crawford, S.; Creech-Eakman, M.; Garcia, J.; Hovland, E.; Koresko, C.; Ligon, R.; Mennesson, B.; Palmer, D.; Shao, M.; Smythe, R.; Swain, M.; Vasisht, G.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Sokoloski, J. L.] Columbia Univ, Dept Phys, New York, NY 10027 USA. [Akeson, R.; Brandenburg, H.; Felizardo, C.; Herstein, J.; Millan-Gabet, R.] Michelson Sci Ctr, Pasadena, CA 91125 USA. [Appleby, E.; Bell, J.; Dahl, W.; Gathright, J.; Hrynevych, M.; Morrison, D.; Panteleeva, T.; Ragland, S.; Summers, K.; Tsubota, K.; Tyau, C.; Wetherell, E.; Wizinowich, P.; Woillez, J.] Calif Assoc Res Astron, WM Keck Observatory, Kamuela, HI 96743 USA. RP Barry, RK (reprint author), NASA, Goddard Space Flight Ctr, Exoplanets & Stellar Astrophys Lab, Greenbelt, MD 20771 USA. RI Kuchner, Marc/E-2288-2012 NR 56 TC 24 Z9 24 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 2008 VL 677 IS 2 BP 1253 EP 1267 DI 10.1086/529422 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 287DV UT WOS:000254898000038 ER PT J AU Rappazzo, AF Velli, M Einaudi, G Dahlburg, RB AF Rappazzo, A. F. Velli, M. Einaudi, G. Dahlburg, R. B. TI Nonlinear dynamics of the parker scenario for coronal heating SO ASTROPHYSICAL JOURNAL LA English DT Article DE MHD; Sun : corona; Sun : magnetic fields; turbulence ID MEAN MAGNETIC-FIELD; MAGNETOHYDRODYNAMIC TURBULENCE; INCOMPRESSIBLE MAGNETOHYDRODYNAMICS; HYDROMAGNETIC TURBULENCE; ALFVENIC TURBULENCE; MHD TURBULENCE; ENERGY-RELEASE; CURRENT SHEETS; SOLAR CORONA; LOOPS AB The Parker or field line tangling model of coronal heating is studied comprehensively via long-time high-resolution simulations of the dynamics of a coronal loop in Cartesian geometry within the framework of reduced magnetohydrodynamics. Slow photospheric motions induce a Poynting flux which saturates by driving an anisotropic turbulent cascade dominated by magnetic energy. In physical space this corresponds to a magnetic topology where magnetic field lines are barely entangled; nevertheless, current sheets (corresponding to the original tangential discontinuities hypothesized by Parker) are continuously formed and dissipated. Current sheets are the result of the nonlinear cascade that transfers energy from the scale of convective motions (similar to 1000 km) down to the dissipative scales, where it is finally converted to heat and/or particle acceleration. Current sheets constitute the dissipative structure of the system, and the associated magnetic reconnection gives rise to impulsive "bursty'' heating events at the small scales. This picture is consistent with the slender loops observed by state-of-the-art (E) UV and X-ray imagers which, although apparently quiescent, shine brightly in these wavelengths with little evidence of entangled features. The different regimes of weak and strong magnetohydrodynamic turbulence that develop and their influence on coronal heating scalings are shown to depend on the loop parameters, and this dependence is quantitatively characterized: weak turbulence regimes and steeper spectra occur in stronger loop fields and lead to larger heating rates than in weak field regions. C1 [Rappazzo, A. F.; Velli, M.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Einaudi, G.] Univ Pisa, Dipartimento Fis E Fermi, I-56127 Pisa, Italy. [Dahlburg, R. B.] USN, Res Lab, Computat Phys & Fluid Dynam Lab, Washington, DC 20375 USA. [Velli, M.] Univ Florence, Dipartimento Astron & Sci Spazio, I-50125 Florence, Italy. RP Rappazzo, AF (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM rappazzo@jpl.nasa.gov; mvelli@jpl.nasa.gov; einaudi@df.unipi.it; rdahlbur@lcp.nrl.navy.mil NR 48 TC 109 Z9 109 U1 1 U2 5 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 2008 VL 677 IS 2 BP 1348 EP 1366 DI 10.1086/528786 PG 19 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 287DV UT WOS:000254898000045 ER PT J AU Hakkila, J Giblin, TW Norris, JP Fragile, PC Bonnell, JT AF Hakkila, Jon Giblin, Timothy W. Norris, Jay P. Fragile, P. Chris Bonnell, Jerry T. TI Correlations between lag, luminosity, and duration in gamma-ray burst pulses SO ASTROPHYSICAL JOURNAL LETTERS LA English DT Article DE gamma rays : bursts ID SPECTRAL LAGS; INTERNAL SHOCKS; QUIESCENT TIMES; BATSE; AFTERGLOW; CLASSIFICATION; SPECTROSCOPY; EVOLUTION; SWIFT AB We derive a new peak lag versus peak luminosity relation in gamma-ray burst (GRB) pulses. We demonstrate conclusively that GRB spectral lags are pulse rather than burst properties and show how the lag versus luminosity relation determined from CCF measurements of burst properties is essentially just a rough measure of this newly derived relation for individual pulses. We further show that most GRB pulses have correlated properties: short-lag pulses have shorter durations, are more luminous, and are harder within a burst than long-lag pulses. We also uncover a new pulse duration versus pulse peak luminosity relation, and indicate that long-lag pulses often precede short-lag pulses. Although most pulse behaviors are supportive of internal shocks (including long-lag pulses), we identify some pulse shapes that could result from external shocks. C1 [Hakkila, Jon; Fragile, P. Chris] Coll Charleston, Dept Phys & Astron, Charleston, SC 29424 USA. [Giblin, Timothy W.] Univ N Carolina, Dept Phys & Astron, Asheville, NC 28804 USA. [Norris, Jay P.] NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA USA. [Bonnell, Jerry T.] NASA, Goddard Space Flight Ctr, UMCP CRESST, Greenbelt, MD 20771 USA. RP Hakkila, J (reprint author), Coll Charleston, Dept Phys & Astron, Charleston, SC 29424 USA. EM hakkilaj@cofc.edu NR 28 TC 46 Z9 46 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA J9 ASTROPHYS J LETT JI Astrophys. J. Lett. PD APR 20 PY 2008 VL 677 IS 2 BP L81 EP L84 DI 10.1086/588094 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 292AC UT WOS:000255237700002 ER PT J AU McBreen, S Foley, S Watson, D Hanlon, L Malesani, D Fynbo, JPU Kann, DA Gehrels, N McGlynn, S Palmer, D AF McBreen, S. Foley, S. Watson, D. Hanlon, L. Malesani, D. Fynbo, J. P. U. Kann, D. A. Gehrels, N. McGlynn, S. Palmer, D. TI The spectral lag of GRB 060505: A likely member of the long-duration class SO ASTROPHYSICAL JOURNAL LETTERS LA English DT Article DE gamma rays : bursts ID GAMMA-RAY BURST; BRIGHT SUPERNOVA; ALERT TELESCOPE; HOST GALAXY; GRB; CONNECTION; LUMINOSITY; GRB-050709; AFTERGLOW; EMISSION AB Two long gamma-ray bursts, GRB 060505 and GRB 060614, occurred in nearby galaxies at redshifts of 0.089 and 0.125, respectively. Due to their proximity and durations, deep follow-up campaigns to search for supernovae (SNe) were initiated. However, none were found in either case, to limits more than 2 orders of magnitude fainter than the prototypical GRB-associated SN, 1998bw. It was suggested that the bursts, in spite of their durations (similar to 4 and 102s), belonged to the population of short GRBs which has been shown to be unrelated to SNe. In the case of GRB 060614 this argument was based on a number of indicators, including the negligible spectral lag, which is consistent with that of short bursts. GRB 060505 has a shorter duration, but no spectral lag was measured. We present the spectral lag measurements of GRB 060505 using Suzaku's Wide Area Monitor and the Swift Burst Alert Telescope. We find that the lag is 0.36 +/- 0.05 s, inconsistent with the lags of short bursts and consistent with the properties of long bursts and SN GRBs. These results support the association of GRB 060505 with other low-luminosity GRBs also found in star-forming galaxies and indicate that at least some massive stars may die without bright SNe. C1 [McBreen, S.] Max Planck Inst Extraterr Phys, D-85748 Garching, Germany. [Foley, S.; Hanlon, L.; McGlynn, S.] Univ Coll Dublin, Sch Phys, Dublin 4, Ireland. [Malesani, D.; Fynbo, J. P. U.] Univ Copenhagen, Dark Cosmol Ctr, Niels Bohr Inst, DK-2100 Copenhagen, Denmark. [Gehrels, N.] Thuringer Landessternwarte Tautenburg, D-07778 Tautenburg, Germany. [Gehrels, N.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Palmer, D.] Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP McBreen, S (reprint author), Max Planck Inst Extraterr Phys, D-85748 Garching, Germany. EM smcbreen@mpe.mpg.de; sfoley@bermuda.ucd.ie; darach@dark-cosmology.dk; lorraine.hanlon@ucd.ie; malesani@dark-cosmology.dk; jfynbo@dark-cosmology.dk; kann@tls-tautenburg.de; gehrels@milkyway.gsfc.nasa.gov; smcglynn@bermuda.ucd.ie; palmer@lanl.gov RI Gehrels, Neil/D-2971-2012; Fynbo, Johan/L-8496-2014; Watson, Darach/E-4521-2015; XRAY, SUZAKU/A-1808-2009 OI Fynbo, Johan/0000-0002-8149-8298; Watson, Darach/0000-0002-4465-8264; NR 56 TC 28 Z9 28 U1 0 U2 5 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 2041-8205 J9 ASTROPHYS J LETT JI Astrophys. J. Lett. PD APR 20 PY 2008 VL 677 IS 2 BP L85 EP L88 DI 10.1086/588189 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 292AC UT WOS:000255237700003 ER PT J AU Mishchenko, MI AF Mishchenko, Michael I. TI Multiple scattering, radiative transfer, and weak localization in discrete random media: Unified microphysical approach SO REVIEWS OF GEOPHYSICS LA English DT Review ID DYNAMIC LIGHT-SCATTERING; DROP-SIZE VARIABILITY; COHERENT BACKSCATTERING; BIDIRECTIONAL REFLECTANCE; PARTICULATE SURFACES; ELECTROMAGNETIC-WAVES; INHOMOGENEOUS CLOUDS; OPTICAL-PROPERTIES; NONERGODIC MEDIA; SPECTRAL ALBEDO AB The radiative transfer theory has been extensively used in geophysics, remote sensing, and astrophysics for more than a century, but its physical basis had remained uncertain until quite recently. This ambiguous situation has finally changed, and the theory of radiative transfer in random particulate media has become a legitimate branch of Maxwell's electromagnetics. This tutorial review is intended to provide an accessible outline of recent basic developments. It discusses elastic electromagnetic scattering by random many-particle groups and summarizes the unified microphysical approach to radiative transfer and the effect of weak localization of electromagnetic waves ( otherwise known as coherent backscattering). It explains the exact meaning of such fundamental concepts as single and multiple scattering, demonstrates how the theories of radiative transfer and weak localization originate in the Maxwell equations, and exposes and corrects certain misconceptions of the traditional phenomenological approach to radiative transfer. It also discusses the challenges facing the theories of multiple scattering, radiative transfer, and weak localization in the context of geophysical applications. C1 NASA, Goddard Inst Space Studies, New York, NY 10025 USA. RP Mishchenko, MI (reprint author), NASA, Goddard Inst Space Studies, 2880 Broadway, New York, NY 10025 USA. EM mmishchenko@giss.nasa.gov RI Mishchenko, Michael/D-4426-2012 NR 168 TC 58 Z9 58 U1 0 U2 14 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 8755-1209 EI 1944-9208 J9 REV GEOPHYS JI Rev. Geophys. PD APR 19 PY 2008 VL 46 IS 2 AR RG2003 DI 10.1029/2007RG000230 PG 33 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 291NX UT WOS:000255205200002 ER PT J AU Lary, DJ Aulov, O AF Lary, D. J. Aulov, O. TI Space-based measurements of HCl: Intercomparison and historical context SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID HALOGEN OCCULTATION EXPERIMENT; ADVECTION-DIFFUSION; AURA SATELLITE; ER-2 AIRCRAFT; POLAR VORTEX; TRACE GASES; EOS MLS; STRATOSPHERE; TRANSPORT; LATITUDE AB The peak in stratospheric HCl was reached in the late 1990s. Between 1998 and 2004 the stratospheric loading of HCl was relatively constant, with some month to month fluctuation; this was followed by a more pronounced decrease in HCl since 2004. We use probability distribution functions ( PDFs) and scatter diagrams for validation and bias characterization of Aura Microwave Limb Sounder ( MLS) HCl retrievals. Both these methods allow us to use large statistical samples and do not require correlative measurements to be colocated in space and time. The bias between the Halogen Occultation Experiment ( HALOE) and Aura MLS is greatest above the 525 K ( similar to 21 km) isentropic surface. The global average mean bias between Aura and the Atmospheric Chemistry Experiment ( ACE) for January 2005 was 2% and between Aura MLS and HALOE was 14%. The widths of the PDFs are a measure of the spatial variability and measurement precision. The Aura MLS HCl PDFs are consistently wider than those for ACE and HALOE, this reflects the retrieval uncertainties. The median observation uncertainty for Aura MLS v1.51 HCl is 12%, and the median ACE v2.2 uncertainty is 8%. We also connect Aura MLS HCl with the heritage of HALOE HCl by using neural networks to learn the interinstrument biases and provide a seamless HCl record from the launch of the Upper Atmosphere Research Satellite ( UARS) in 1991 to the present. C1 [Lary, D. J.; Aulov, O.] Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. [Lary, D. J.; Aulov, O.] NASA Goddard Space Flight Ctr, Atmospher Chem & Dynam Branch, Greenbelt, MD USA. RP Lary, DJ (reprint author), Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. EM david.lary@umbc.edu RI Lary, David/A-6163-2010 NR 32 TC 11 Z9 11 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 18 PY 2008 VL 113 IS D15 AR D15S04 DI 10.1029/2007JD008715 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 291ND UT WOS:000255203200001 ER PT J AU Schroeder, C Rodionov, DS McCoy, TJ Jolliff, BL Gellert, R Nittler, LR Farrand, WH Johnson, JR Ruff, SW Ashley, JW Mittlefehldt, DW Herkenhoff, KE Fleischer, I Haldemann, AFC Klingelhoefer, G Ming, DW Morris, RV de Souza, PA Squyres, SW Weitz, C Yen, AS Zipfel, J Economou, T AF Schroeder, C. Rodionov, D. S. McCoy, T. J. Jolliff, B. L. Gellert, R. Nittler, L. R. Farrand, W. H. Johnson, J. R. Ruff, S. W. Ashley, J. W. Mittlefehldt, D. W. Herkenhoff, K. E. Fleischer, I. Haldemann, A. F. C. Klingelhoefer, G. Ming, D. W. Morris, R. V. de Souza, P. A., Jr. Squyres, S. W. Weitz, C. Yen, A. S. Zipfel, J. Economou, T. TI Meteorites on Mars observed with the Mars Exploration Rovers SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Review ID IRON-METEORITES; CHEMICAL CLASSIFICATION; GE CONCENTRATIONS; MERIDIANI-PLANUM; GERMANIUM CONCENTRATIONS; OPPORTUNITY ROVER; TERRESTRIAL AGE; 1ST SHERGOTTITE; HIGH ABUNDANCE; BOUNCE ROCK AB Reduced weathering rates due to the lack of liquid water and significantly greater typical surface ages should result in a higher density of meteorites on the surface of Mars compared to Earth. Several meteorites were identified among the rocks investigated during Opportunity's traverse across the sandy Meridiani plains. Heat Shield Rock is a IAB iron meteorite and has been officially recognized as "Meridiani Planum." Barberton is olivine-rich and contains metallic Fe in the form of kamacite, suggesting a meteoritic origin. It is chemically most consistent with a mesosiderite silicate clast. Santa Catarina is a brecciated rock with a chemical and mineralogical composition similar to Barberton. Barberton, Santa Catarina, and cobbles adjacent to Santa Catarina may be part of a strewn field. Spirit observed two probable iron meteorites from its Winter Haven location in the Columbia Hills in Gusev Crater. Chondrites have not been identified to date, which may be a result of their lower strengths and probability to survive impact at current atmospheric pressures. Impact craters directly associated with Heat Shield Rock, Barberton, or Santa Catarina have not been observed, but such craters could have been erased by eolian-driven erosion. C1 [Schroeder, C.; Mittlefehldt, D. W.; Morris, R. V.] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. [Ruff, S. W.; Ashley, J. W.] Arizona State Univ, Mars Space Flight Facilit, Tempe, AZ 85287 USA. [de Souza, P. A., Jr.] V&M France, CEV, F-59620 Aulnoye Ayemeries, France. [Economou, T.] Univ Chicago, Enrico Fermi Inst, LASR, Chicago, IL 60637 USA. [Farrand, W. H.] Space Sci Inst, Boulder, CO 80301 USA. [Fleischer, I.; Klingelhoefer, G.] Johannes Gutenberg Univ Mainz, Inst Anorgan Chem & Analyt Chem, D-55099 Mainz, Germany. [Gellert, R.] Univ Guelph, Dept Phys, Guelph, ON N1G 2W1, Canada. [Haldemann, A. F. C.] European Space Agcy, European Space Res & Technol Ctr, HME ME, NL-2200 AG Noordwijk, Netherlands. [Johnson, J. R.; Herkenhoff, K. E.] US Geol Survey, Astrogeol Team, Flagstaff, AZ 86001 USA. [Jolliff, B. L.] Washington Univ, Dept Earth & Planetary Sci, St Louis, MO 63130 USA. [McCoy, T. J.] Smithsonian Inst, Natl Museum Nat Hist, Washington, DC 20560 USA. [Ming, D. W.] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. [Nittler, L. R.] Carnegie Inst Sci, Dept Terr Magnetism, Washington, DC 20015 USA. [Squyres, S. W.] Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. [Weitz, C.] Planetary Sci Inst, Tucson, AZ 85719 USA. [Yen, A. S.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Zipfel, J.] Forschunginst & Natmusuem Senckenberg, D-60325 Frankfurt, Germany. RP Schroeder, C (reprint author), NASA, Lyndon B Johnson Space Ctr, Mail Code KR,2101 NASA Pkwy, Houston, TX 77058 USA. EM christian.schroeder-1@nasa.gov RI de Souza, Paulo/B-8961-2008; Schroder, Christian/B-3870-2009; Centre, TasICT/D-1212-2011; Johnson, Jeffrey/F-3972-2015 OI de Souza, Paulo/0000-0002-0091-8925; Schroder, Christian/0000-0002-7935-6039; NR 101 TC 42 Z9 42 U1 0 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9097 EI 2169-9100 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD APR 18 PY 2008 VL 113 IS E6 AR E06S22 DI 10.1029/2007JE002990 PG 19 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 291NO UT WOS:000255204300001 ER PT J AU Fromm, M Torres, O Diner, D Lindsey, D Hull, BV Servranckx, R Shettle, EP Li, Z AF Fromm, M. Torres, O. Diner, D. Lindsey, D. Hull, B. Vant Servranckx, R. Shettle, E. P. Li, Z. TI Stratospheric impact of the Chisholm pyrocumulonimbus eruption: 1. Earth-viewing satellite perspective SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID IMAGING SPECTRORADIOMETER MISR; BIOMASS BURNING PARTICLES; AEROSOL OPTICAL DEPTH; FOREST-FIRE SMOKE; PART II; CLOUD; MODIS; RETRIEVAL; SIMULATION; CONVECTION AB The pyrocumulonimbus storm near Chisholm, Alberta, on 28 May 2001 has been studied in depth. However, the impact of this eruption on the lower stratosphere has not been characterized. Here and in a companion paper we explore this topic. This paper focuses on the "young" Chisholm smoke plume, from the age of similar to 3 h to 1 week, as observed by Earth-viewing satellite instruments. (The companion paper presents strictly profile data.) GOES visible and infrared image loops reveal the pyroconvective life cycle and initial transport of the smoke cloud. MISR stereographic heights are the first of their kind for a stratospheric cloud, showing smoke up to 5 km above the tropopause on 29 May. MODIS IR and visible images are analyzed to give constraints on plume height, thickness, and particle size. Infrared brightness temperature analyses reveal unique aspects of the "day-after" Chisholm plume. Particle sizes are 1/3 to 1/2 compared to normal cirrus crystals. The daytime 29 May plume is optically thick at tropopause temperatures yet smoky brown. A transition from deep anvil blow off to "dry" smoke is still occurring after similar to 1.5 d. TOMS aerosol index is used as a proxy for areas of particularly high smoke plume altitude. The Chisholm smoke in the upper troposphere and lower stratosphere is traced with AI for 1 week as the plume blows across North America to western Europe. First estimates are made of stratospheric smoke mass in relation to emissions during pyroconvection. The 29 May stratospheric Chisholm pyroCb plume contains a mass between similar to 1.39 x 10(4) and 1.09 x 10(5) t. This represents between similar to 10% and 121% of total particle mass emitted from the fire on 28 May, calling into question some frequently assumed values for smoke single scatter albedo and/or emission estimates. Strictly in terms of mass, the stratospheric Chisholm plume amounted to similar to 15% of background Northern Hemispheric stratospheric sulfate aerosol. Overall, the young pyroCb plume is seen to be a peculiar mixture of smoke aerosols and water-ice that confounds operational cloud/aerosol detection routines and exhibits extreme, and still mysterious, composition and life cycle features. C1 [Fromm, M.; Shettle, E. P.] USN, Res Lab, Washington, DC 20375 USA. [Torres, O.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Torres, O.] Univ Maryland Baltimore Cty, Joint Ctr Earth Syst Technol, Greenbelt, MD USA. [Diner, D.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Lindsey, D.] NOAA, Natl Environm Satellite Data & Informat Serv, Reg & Mesoscale Meteorol Branch, Ft Collins, CO 80523 USA. [Hull, B. Vant] CUNY City Coll, NOAA, Cooperat Remote Sensing Sci & Technol Ctr, New York, NY 10031 USA. [Servranckx, R.] Canadian Meteorol Ctr, Dorval, PQ H9P 1J3, Canada. [Li, Z.] Univ Maryland, Earth Syst Sci Interdisciplinary Ctr, College Pk, MD 20742 USA. RP Fromm, M (reprint author), USN, Res Lab, Washington, DC 20375 USA. EM mike.fromm@nrl.navy.mil RI Li, Zhanqing/F-4424-2010; Fromm, Michael/F-4639-2010; Torres, Omar/G-4929-2013; Lindsey, Dan/F-5607-2010 OI Li, Zhanqing/0000-0001-6737-382X; Lindsey, Dan/0000-0002-0967-5683 NR 55 TC 21 Z9 22 U1 2 U2 12 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 17 PY 2008 VL 113 IS D8 AR D08202 DI 10.1029/2007JD009153 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 291MW UT WOS:000255202500003 ER PT J AU Fromm, M Shettle, EP Fricke, KH Ritter, C Trickl, T Giehl, H Gerding, M Barnes, JE O'Neill, M Massie, ST Blum, U McDermid, IS Leblanc, T Deshler, T AF Fromm, M. Shettle, E. P. Fricke, K. H. Ritter, C. Trickl, T. Giehl, H. Gerding, M. Barnes, J. E. O'Neill, M. Massie, S. T. Blum, U. McDermid, I. S. Leblanc, T. Deshler, T. TI Stratospheric impact of the Chisholm pyrocumulonimbus eruption: 2. Vertical profile perspective SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID NORTHERN-HEMISPHERE WINTER; FOREST-FIRE SMOKE; POAM-III; SAGE-II; TROPOSPHERE EXCHANGE; LIDAR MEASUREMENTS; RAMAN LIDAR; AEROSOL; EXTINCTION; TRANSPORT AB Extreme pyrocumulonimbus (pyroCb) blowups that pollute the stratosphere have been documented on at least five occasions. However, the frequency of these events is still uncertain. One published pyroCb case study, the Chisholm Fire in May 2001, was restricted to the convective phase and its immediate aftermath. Here and in a companion paper we describe the stratospheric impact of the Chisholm pyroCb. The companion paper focuses on nadir satellite views of the plume. This paper synthesizes a broad array of space-, balloon-, and ground-based profile measurements. The Chisholm pyroCb, which we identify as the singular cause of stratospheric aerosol increase in northern spring/summer of 2001, created a doubling of the zonal average aerosol optical depth in the lowermost stratosphere. The meridional spread of the plume was from the tropics (20 degrees N) to the high Arctic (79 degrees N) within the first month. The stratospheric Chisholm smoke became a hemispheric phenomenon in midlatitudes and northern tropics and persisted for at least 3 months. A size-resolved particle concentration profile over Laramie, Wyoming, indicated a lower stratospheric aerosol with a twofold to threefold increase in volume of particles with radii between 0.3 and 0.6 mm. We also find evidence of localized warming in the air masses of four of the lidar-measured smoke layers. This work contains the first reported stratospheric smoke layers measured by lidar at Ny Alesund, Esrange, Kuhlungsborn, Garmisch-Partenkirchen, Boulder, and Mauna Loa. In addition, the first detection of smoke-enhanced aerosol extinction at near IR wavelengths by the Halogen Occultation Experiment (HALOE) is introduced. C1 [Fromm, M.; Shettle, E. P.] USN, Res Lab, Washington, DC 20375 USA. [Fricke, K. H.] Univ Bonn, Inst Phys, D-5300 Bonn, Germany. [Ritter, C.] Alfred Wegener Inst Polar & Marine Res, Potsdam, Germany. [Trickl, T.; Giehl, H.] Forschungszentrum Karlsruhe, IMK IFU, Garmisch Partenkirchen, Germany. [Gerding, M.] Leibniz Inst Atmospher Phys, Kuhlungsborn, Germany. [Barnes, J. E.; O'Neill, M.] NOAA, Global Monitoring Div, Boulder, CO USA. [Massie, S. T.] Natl Ctr Atmospher Res, Div Atmospher Chem, Boulder, CO 80307 USA. [Blum, U.] Forsvarets Forskningsinst, Kjeller, Norway. [McDermid, I. S.; Leblanc, T.] CALTECH, Jet Prop Lab, Table Mt Facil, Wrightwood, CA USA. [Deshler, T.] Univ Wyoming, Dept Atmospher Sci, Laramie, WY 82071 USA. RP Fromm, M (reprint author), USN, Res Lab, Washington, DC 20375 USA. EM mike.fromm@nrl.navy.mil RI Fromm, Michael/F-4639-2010; Trickl, Thomas/F-7331-2010; Garmisch-Pa, Ifu/H-9902-2014 NR 62 TC 19 Z9 20 U1 0 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 17 PY 2008 VL 113 IS D8 AR D08203 DI 10.1029/2007JD009147 PG 19 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 291MW UT WOS:000255202500002 ER PT J AU Holzer, M Hall, TM AF Holzer, Mark Hall, Timothy M. TI Tropospheric transport climate partitioned by surface origin and transit time SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID GENERAL-CIRCULATION MODEL; AIR-POLLUTION TRANSPORT; UNITED-STATES; ATMOSPHERIC TRANSPORT; PACIFIC TRANSPORT; ASIAN EMISSIONS; NORTH-AMERICA; ART.; DISTRIBUTIONS; OZONE AB We perform the first analysis of tropospheric transport using the global boundary propagator Green function, G, which partitions air at every point and time according to both the transit time since last surface contact and the location of that contact. We compute G for a 3-year period with the MATCH model driven by NCEP reanalyses. Last contact time is resolved in 3-d intervals, and last-contact location is resolved with a global tiling of 41 patches concentrated in the Northern Hemisphere. The transport climate is quantified for four midlatitude receptor regions in terms of the seasonal mean surface-origin and transit-time partitioning of the column burden, the surface flux of newly arriving air, and the distribution of air mass in transit from source to receptor surface. At long transit times a nearly receptor-independent pattern of last-contact location is governed by where air is injected into the upper troposphere by deep convection and the high terrain of Tibet. The receptor origin composition of the column burden changes only slowly after similar to 40 d for winter and fall, while the composition of the flux onto the receptor continues to change at similar to 60 d. European and SE Asian air contribute comparably to the flux onto eastern North America, in spite of SE Asian air having the dominant burden. The flux of European air onto SE Asia in winter and fall is larger than the flux of SE Asian air onto Europe. The surface-to-surface transport mass distribution, R, is used to identify transit-time-dependent source-receptor teleconnections. C1 [Holzer, Mark; Hall, Timothy M.] Columbia Univ, Dept Appl Phys & Appl Math, New York, NY 10027 USA. [Holzer, Mark] Univ British Columbia, Dept Earth & Ocean Sci, Atmospher Sci Program, Vancouver, BC V5Z 1M9, Canada. [Holzer, Mark] Langara Coll, Dept Phys, Vancouver, BC, Canada. [Holzer, Mark; Hall, Timothy M.] NASA, Goddard Inst Space Studies, New York, NY 10025 USA. RP Holzer, M (reprint author), Columbia Univ, Dept Appl Phys & Appl Math, New York, NY 10027 USA. EM hm2220@columbia.edu; thall@giss.nasa.gov NR 43 TC 6 Z9 6 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 17 PY 2008 VL 113 IS D8 AR D08104 DI 10.1029/2007JD009115 PG 20 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 291MW UT WOS:000255202500001 ER PT J AU Lui, ATY Sibeck, DG Phan, T Angelopoulos, V McFadden, J Carlson, C Larson, D Bonnell, J Glassmeier, KH Frey, S AF Lui, A. T. Y. Sibeck, D. G. Phan, T. Angelopoulos, V. McFadden, J. Carlson, C. Larson, D. Bonnell, J. Glassmeier, K. -H. Frey, S. TI Reconstruction of a magnetic flux rope from THEMIS observations SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID CLUSTER DATA; MAGNETOPAUSE; MAGNETOMETER AB We investigate a magnetic flux rope (MFR) observed by THEMIS near the duskside magnetopause on 20 May 2007 using the reconstruction technique based on solving the Grad-Shafranov equation. The MFR has characteristics distinct from the adjacent magnetosheath and magnetosphere regions. In spite of these differences, the reconstruction result shows that the MFR is connected simultaneously with both the magnetosheath and the magnetosphere in terms of the magnetic vector potential characteristics. This result provides strong evidence that the MFR represents the union of these two regions. It has a small spatial dimension of similar to 0.5 R-E, a strong core magnetic field of > 50 nT, and an intense axial current density of > 40 nA/m(2) with non-negligible current densities transverse to its axis. C1 [Lui, A. T. Y.] Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. [Angelopoulos, V.] Univ Calif Los Angeles, IGPP, Los Angeles, CA 90095 USA. [Glassmeier, K. -H.] Tech Univ Carolo Wilhelmina Braunschweig, IGEP, D-38106 Braunschweig, Germany. [Phan, T.; McFadden, J.; Carlson, C.; Larson, D.; Bonnell, J.; Frey, S.] Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. [Sibeck, D. G.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Lui, ATY (reprint author), Johns Hopkins Univ, Appl Phys Lab, Johns Hopkins Rd, Laurel, MD 20723 USA. EM tony.lui@jhuapl.edu RI Sibeck, David/D-4424-2012 NR 18 TC 19 Z9 19 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 EI 1944-8007 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR 16 PY 2008 VL 35 IS 17 AR L17S05 DI 10.1029/2007GL032933 PG 7 WC Geosciences, Multidisciplinary SC Geology GA 291MQ UT WOS:000255201900001 ER PT J AU Thornhill, KL Chen, G Dibb, J Jordan, CE Omar, A Winstead, EL Schuster, G Clarke, A McNaughton, C Scheuer, E Blake, D Sachse, G Huey, LG Singh, HB Anderson, BE AF Thornhill, K. Lee Chen, Gao Dibb, Jack Jordan, Carolyn E. Omar, Ali Winstead, Edward L. Schuster, Greg Clarke, Antony McNaughton, Cameron Scheuer, Eric Blake, Donald Sachse, Glen Huey, L. G. Singh, H. B. Anderson, Bruce E. TI The impact of local sources and long-range transport on aerosol properties over the northeast US region during INTEX-NA SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ASIAN CONTINENTAL OUTFLOW; PACIFIC TRACE-P; SUBSONIC ASSESSMENT OZONE; OXIDE EXPERIMENT SONEX; PEM-WEST-B; CHEMICAL-COMPOSITION; REACTIVE NITROGEN; LIGHT-ABSORPTION; UNITED-STATES; EVOLUTION AB We use data collected aboard the NASA DC-8 aircraft during the summer 2004, Intercontinental Transport and Chemical Evolution Experiment over North America (INTEX-NA) field campaign to examine the origin, composition, physical and optical properties of aerosols within air masses sampled over and downwind of the northeastern U. S. We note that aerosol concentrations within the region exhibited steep vertical gradients and significant variability in both time and space. An examination of air mass chemical signatures and backward trajectories indicates that transport from four, significantly different source regions contributed to the variability: the subtropical Atlantic Ocean (AO); the U. S. west coast and eastern Pacific (WCP); the U. S. east coast and Midwestern states (EC); and northwest Canada and Alaska (CA). AO air masses were typically confined to below 2 km altitude, exhibited low pollutant contents, contained enhanced levels of sea salt, and were typically observed when the Bermuda High strengthened. The most common air mass present in the upper troposphere, WCP air often contained weak dust and aged pollution enhances from convective input occurring over the central part of the continent. CA air exhibited enhancements in anthropogenic pollution tracers below 2 km and contained some black-carbon rich haze layers between 3 and 5 km that could be traced to forest fires burning in western Canada and Alaska. EC air was prevalent at lower elevations throughout the study area and exhibited enhanced scattering along with elevated levels of sulfate aerosols and combustion tracers. There is an overall balance between the observed cations and anions for all cases, except EC air mass below 4 km. C1 [Thornhill, K. Lee; Winstead, Edward L.] SSAI, Hampton, VA USA. [Chen, Gao; Omar, Ali; Schuster, Greg; Sachse, Glen; Anderson, Bruce E.] NASA, Langley Res Ctr, Hampton, VA 23665 USA. [Blake, Donald] Univ Calif Irvine, Dept Chem, Irvine, CA 92717 USA. [Clarke, Antony; McNaughton, Cameron] Univ Hawaii, Sch Ocean & Earth Sci & Technol, Honolulu, HI 96822 USA. [Dibb, Jack; Jordan, Carolyn E.; Scheuer, Eric] Univ New Hampshire, Inst Study Earth Oceans & Space, Durham, NH 03824 USA. [Huey, L. G.] Georgia Inst Technol, Sch Earth & Atmospher Sci, Atlanta, GA 30332 USA. [Singh, H. B.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Thornhill, KL (reprint author), SSAI, Hampton, VA USA. EM kenneth.l.thornhill@nasa.gov; jack.dibb@unh.edu; tclarke@soest.hawaii.edu; dblake@orion.oac.uci.edu; greg.huey@eas.gatch.edu; hanwant.b.singh@nasa.gov; bruce.e.anderson@nasa.gov RI Omar, Ali/D-7102-2017 OI Omar, Ali/0000-0003-1871-9235 NR 49 TC 13 Z9 13 U1 0 U2 14 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 16 PY 2008 VL 113 IS D8 AR D08201 DI 10.1029/2007JD008666 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 291MV UT WOS:000255202400003 ER PT J AU Otake, T Lasaga, AC Ohmoto, H AF Otake, Tsubasa Lasaga, Antonio C. Ohmoto, Hiroshi TI Ab initio calculations for equilibrium fractionations in multiple sulfur isotope systems SO CHEMICAL GEOLOGY LA English DT Article DE ab initio calculation; sulfur isotopes; equilibrium; mass-dependent fractionation; solvent model; anharmonicity ID PARTITION-FUNCTION RATIOS; MOLECULAR-ORBITAL THEORY; ANISOTROPIC DIELECTRICS; HYDROTHERMAL SYSTEMS; AQUEOUS-SOLUTION; IONIC-SOLUTIONS; BORIC ACIDS; SULFATE; GEOCHEMISTRY; HYDROGEN AB Ab initio calculations of vibrational frequencies (v), reduced partition function ratios (0) of various gaseous and aqueous sulfur-bearing compounds, and isotopic fractionation factors (a) between them were performed on the multiple isotope systems using the Hartree-Fock (HF) and the Becke three-parameter Lee-Yang-Parr (B3LYP) density functional methods. Based on the comparison of the geometry, vibrational frequencies, and fractionation factors with those determined experimentally, the HF/6-31G(d) was chosen as the optimal method for the sulfur isotope systems. The results of computation for multiple sulfur fractionation factors indicate that the mass-dependent relationships, i.e., ((33)alpha - 1)/((34)alpha - 1) and ((36)alpha - 1)/((34)alpha - 1) values, converge only at high temperature (e.g., T>500 degrees C) to 0.515 and 1.89, respectively, which are the values previously derived from the Bigeleisen-Mayer approximations. However, they significantly deviate from these values with decreasing temperature, and depending on the sulfur species pairs that are involved in equilibrium isotope exchange reactions. The ((33)alpha- 1)/((34)alpha - 1) values and the ((36)alpha - 1)/ ((34)alpha- 1) values range from 0.505 to 0.517 and from 1.88 to 1.96, respectively, at 0 degrees C. An isotopic crossover relationship, in which the fractionation factor changes from > 1.0 to < 1.0 (or from < 1.0 to > 1.0) about a specific temperature (i.e., crossover temperature), was observed in several species couples (e.g., S-2-H2S, S-8-H2S, CS2-H2S, SO3-SO4(aq)2-). Since the crossover temperatures vary among different isotope molecules, large changes in the ((33)alpha -1)/((34)alpha - 1) and ((36)alpha - 1)/((34)alpha - 1) values (e.g., > 1 to <0) also occur near the crossover temperatures. The effects of solvation on the fractionation factors were investigated using the PCM models. The dielectric constant (P) of solvent, which is the dominant solvent characteristic, affects the fractionation factors between gaseous and aqueous species (e.g., SO2(g) and SO2(aq)), but the effect levels out for epsilon > 20. Among the solvent models, the IEF-PCM model yields the greatest fractionation factors between gaseous and aqueous species. Overall, temperature, harmonic frequency, and mass of atoms bonded to sulfur (M are the three important parameters affecting the reduced partition function ratios, fractionation factors, and mass-dependent relationships. By decreasing temperature and increasing frequency and mass, the 1000((34)beta - 1) values increase and the ((33)beta - 1)/((34)beta - 1) values decrease (i.e., deviate from "expected" 0.515). The ((33)beta - 1)/((34)beta - 1) values converge to 0.516 only at higher temperature (e.g., T>600 degrees C), lower frequency (omega(e) <500 cm(-1)), and smaller mass (M<7 amu) and become as low as 0.503 at T=50 degrees C, omega(e) = 2500 cm(-1), and M=56 amu. (C) 2008 Elsevier B.V All rights reserved. C1 [Otake, Tsubasa; Ohmoto, Hiroshi] Penn State Univ, Dept Geosci, University Pk, PA 16802 USA. [Otake, Tsubasa; Ohmoto, Hiroshi] Penn State Univ, NASA, Astrobiol Inst, University Pk, PA 16802 USA. [Lasaga, Antonio C.] Geokinet, State Coll, PA 16803 USA. RP Otake, T (reprint author), Penn State Univ, Dept Geosci, 437 Deike Bldg, University Pk, PA 16802 USA. EM totake@geosc.psu.edu RI Otake, Tsubasa/D-6137-2012 NR 69 TC 44 Z9 46 U1 3 U2 42 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2541 EI 1878-5999 J9 CHEM GEOL JI Chem. Geol. PD APR 15 PY 2008 VL 249 IS 3-4 BP 357 EP 376 DI 10.1016/j.chemgeo.2008.01.020 PG 20 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 298XJ UT WOS:000255720100010 ER PT J AU Decyk, VK Gardner, HJ AF Decyk, Viktor K. Gardner, Henry J. TI Object-oriented design patterns in Fortran 90/95: mazev1, mazev2 and mazev3 SO COMPUTER PHYSICS COMMUNICATIONS LA English DT Article DE object-oriented; design patterns; Fortran AB This paper discusses the concept, application, and usefulness of software design patterns for scientific programming in Fortran 90/95. An example from the discipline of object-oriented design patterns, that of a game based on navigation through a maze, is used to describe how some important patterns can be implemented in Fortran 90/95 and how the progressive introduction of design patterns can usefully restructure Fortran software as it evolves. This example is complemented by a discussion of how design patterns have been used in a real-life simulation of Particle-in-Cell plasma physics. The following patterns are mentioned in this paper: Factory, Strategy, Template, Abstract Factory and Facade. Program summary Program title: mazev1, mazev2, mazev3 Catalogue identifier. AEAI_v1_0 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/AEAI-v1-0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 1958 No. of bytes in distributed program, including test data, etc.: 17 100 Distribution format: tar.gz Programming language: Fortran 95 Computer: PC/Mac Operating system: Unix/Linux/Mac (FreeBSD)/Windows (Cygwin) RAM: These are interactive programs with small (KB) memory requirements Classification: 6.5, 20 Nature of problem: A sequence of programs which demonstrate the use of object oriented design patterns for the restructuring of Fortran 90/95 software. The programs implement a simple maze game similar to that described in [1]. Solution method: Restructuring uses versions of the Template, Strategy and Factory design patterns. Running time: Interactive. C1 [Decyk, Viktor K.] Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. [Decyk, Viktor K.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Gardner, Henry J.] Australian Natl Univ, Coll Engn & Comp Sci, Dept Comp Sci, Canberra, ACT 0200, Australia. RP Decyk, VK (reprint author), Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. EM decyk@physics.ucla.edu; henry.gardner@anu.edu.au NR 12 TC 6 Z9 6 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0010-4655 J9 COMPUT PHYS COMMUN JI Comput. Phys. Commun. PD APR 15 PY 2008 VL 178 IS 8 BP 611 EP 620 DI 10.1016/j.cpc.2007.11.013 PG 10 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 295XC UT WOS:000255506500007 ER PT J AU Su, CH AF Su, Ching-Hua TI Energy band gap, intrinsic carrier concentration, and Fermi level of CdTe bulk crystal between 304 and 1067 K SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID PHYSICAL VAPOR TRANSPORT; TEMPERATURE-DEPENDENCE; CADMIUM TELLURIDE; PARTIAL PRESSURES; DEFECT STRUCTURE; ABSORPTION-EDGE; THERMAL-CONDUCTIVITY; SINGLE-CRYSTAL; GROWTH; ZNSE AB Optical transmission measurements were performed on CdTe bulk single crystals. It was found that when sliced and polished CdTe wafers were used, a white film started to develop on the sample surface and the wafer became opaque when it was heated above 530 K. Therefore, a bulk crystal of CdTe was first grown in the window area by physical vapor transport. The optical transmission was then measured between 304 and 1067 K and from which the energy band gap was derived. The band gaps of CdTe can fit well as a function of temperature by the Varshni expression. Using the band gap data, the high temperature electron-hole equilibrium was numerically calculated by assuming Kane's conduction band structure and a light-hole and a heavy-hole parabolic valence bands. The calculated intrinsic carrier concentrations agree well with the experimental data previously reported. The calculated intrinsic Fermi levels between 200 and 1200 K were also presented. C1 NASA, George C Marshall Space Flight Ctr, EM30 Mat & Proc Lab, Engn Directorate, Huntsville, AL 35812 USA. RP Su, CH (reprint author), NASA, George C Marshall Space Flight Ctr, EM30 Mat & Proc Lab, Engn Directorate, Huntsville, AL 35812 USA. EM ching.h.su@nasa.gov NR 45 TC 8 Z9 8 U1 1 U2 7 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-8979 EI 1089-7550 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 2008 VL 103 IS 8 AR 084903 DI 10.1063/1.2899087 PG 6 WC Physics, Applied SC Physics GA 295DW UT WOS:000255456200176 ER PT J AU Naud, CM Del Genio, A Mace, GG Benson, S Clothiaux, EE Kollias, P AF Naud, Catherine M. Del Genio, Anthony Mace, Gerald G. Benson, Sally Clothiaux, Eugene E. Kollias, Pavlos TI Impact of dynamics and atmospheric state on cloud vertical overlap SO JOURNAL OF CLIMATE LA English DT Article ID LAYER OVERLAP; RADAR; REANALYSIS; MODEL; SIMULATIONS AB The observation and representation in general circulation models (GCMs) of cloud vertical overlap are the objects of active research due to their impacts on the earth's radiative budget. Previous studies have found that vertically contiguous cloudy layers show a maximum overlap between layers up to several kilometers apart but tend toward a random overlap as separations increase. The decorrelation length scale that characterizes the progressive transition from maximum to random overlap changes from one location and season to another and thus may be influenced by large-scale vertical motion, wind shear, or convection. Observations from the U.S. Department of Energy Atmospheric Radiation Measurement program ground-based radars and lidars in midlatitude and tropical locations in combination with reanalysis meteorological fields are used to evaluate how dynamics and atmospheric state influence cloud overlap. For midlatitude winter months, strong synoptic-scale upward motion maintains conditions closer to maximum overlap at large separations. In the tropics, overlap becomes closer to maximum as convective stability decreases. In midlatitude subsidence and tropical convectively stable situations, where a smooth transition from maximum to random overlap is found on average, large wind shears sometimes favor minimum overlap. Precipitation periods are discarded from the analysis but, when included, maximum overlap occurs more often at large separations. The results suggest that a straightforward modification of the existing GCM mixed maximum-random overlap parameterization approach that accounts for environmental conditions can capture much of the important variability and is more realistic than approaches that are only based on an exponential decay transition from maximum to random overlap. C1 [Naud, Catherine M.; Del Genio, Anthony] NASA, Goddard Inst Space Studies, New York, NY 10025 USA. [Naud, Catherine M.] Columbia Univ, Dept Appl Phys & Appl Math, New York, NY USA. [Mace, Gerald G.; Benson, Sally] Univ Utah, Dept Meteorol, Salt Lake City, UT 84112 USA. [Clothiaux, Eugene E.] Penn State Univ, Dept Meteorol, University Pk, PA 16802 USA. [Kollias, Pavlos] McGill Univ, Dept Atmospher & Ocean Sci, Montreal, PQ, Canada. RP Naud, CM (reprint author), NASA, Goddard Inst Space Studies, 2800 Broadway, New York, NY 10025 USA. EM cnaud@giss.nasa.gov RI Del Genio, Anthony/D-4663-2012 OI Del Genio, Anthony/0000-0001-7450-1359 NR 22 TC 21 Z9 22 U1 1 U2 7 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 EI 1520-0442 J9 J CLIMATE JI J. Clim. PD APR 15 PY 2008 VL 21 IS 8 BP 1758 EP 1770 DI 10.1175/2007JCLI1828.1 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 291CG UT WOS:000255169300007 ER PT J AU Liu, ZY Omar, A Vaughan, M Hair, J Kittaka, C Hu, YX Powell, K Trepte, C Winker, D Hostetler, C Ferrare, R Pierce, R AF Liu, Zhaoyan Omar, Ali Vaughan, Mark Hair, Johnathan Kittaka, Chieko Hu, Yongxiang Powell, Kathleen Trepte, Charles Winker, David Hostetler, Chris Ferrare, Richard Pierce, Robert TI CALIPSO lidar observations of the optical properties of Saharan dust: A case study of long-range transport SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID TO-BACKSCATTER RATIO; RAMAN LIDAR; WATER CLOUDS; PUERTO-RICO; MULTIPLE-SCATTERING; AEROSOL EXTINCTION; PARTICLES; CIRRUS; PRIDE; DEPOLARIZATION AB An extensive dust storm originating on 17 August 2006 in North Africa was observed and tracked by the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) lidar. Over the next several days, the dust layer moved westward across the Atlantic Ocean and into the Gulf of Mexico. The initial stages of the event were examined using a sequence of CALIPSO measurements. The first of these was acquired very near the source on 18 August. Successive measurements were made over the Atlantic Ocean on 19 and 20 August, at respective locations approximately similar to 1300 km and similar to 2400 km from the source region. The later stages of the event were assessed using measurements acquired by the NASA Langley Research Center airborne HSRL over the Gulf of Mexico on 28 August. Within the free troposphere, the intrinsic optical properties of the dust remain relatively unchanged for the first 3 d of transport over the Atlantic Ocean. This is consistent with previous in situ measurements that have shown that there is little change in the size distribution of dust as it crosses the Atlantic. After the 10 d journey to the Gulf of Mexico, some changes are seen in the lidar ratios, the backscatter color ratio, and the optical depth ratio. The linear depolarization ratio appears to remain essentially constant (similar to 0.32) at all four locations mentioned above, demonstrating a notable consistency in the dust particle nonsphericity. The measured 532 nm lidar ratios are 41 +/- 3, 41 +/- 4, 41 +/- 6 and 45.8 +/- 0.8 sr, respectively, at locations near the source, over the Atlantic Ocean, and in the Gulf of Mexico. The corresponding 1064 nm lidar ratios are 52 +/- 5, 55 +/- 5, 54 +/- 13 and 44 +/- 8.3 sr. The 532 nm lidar ratios are consistent with previous measurements and with CALIPSO's prelaunch models. The lidar ratios retrieved at 1064 nm are somewhat larger than would be expected on the basis of existing modeling studies. The backscatter color ratios are 0.74 +/- 0.07, 0.75 +/- 0.08, 0.72 +/- 0.04 and 0.62 +/- 0.01, and the optical depth ratios are 0.97 +/- 0.02, 1.01 +/- 0.05, 0.93 +/- 0.17 and 0.62 +/- 0.13, respectively. C1 [Liu, Zhaoyan] Natl Inst Aerosp, Hampton, VA 23666 USA. [Omar, Ali; Hair, Johnathan; Hu, Yongxiang; Trepte, Charles; Winker, David; Hostetler, Chris; Ferrare, Richard; Pierce, Robert] NASA, Langley Res Ctr, Hampton, VA 23681 USA. [Vaughan, Mark; Kittaka, Chieko; Powell, Kathleen] Sci Syst & Applicat Inc, Hampton, VA 23681 USA. RP Liu, ZY (reprint author), Natl Inst Aerosp, 100 Explorat Way, Hampton, VA 23666 USA. EM zhaoyan.liu-1@nasa.gov RI Liu, Zhaoyan/A-9604-2009; Liu, Zhaoyan/B-1783-2010; Hu, Yongxiang/K-4426-2012; Omar, Ali/D-7102-2017 OI Liu, Zhaoyan/0000-0003-4996-5738; Omar, Ali/0000-0003-1871-9235 NR 66 TC 119 Z9 121 U1 3 U2 26 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 15 PY 2008 VL 113 IS D7 AR D07207 DI 10.1029/2007JD008878 PG 20 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 291MU UT WOS:000255202300001 ER PT J AU Matichuk, RI Colarco, PR Smith, JA Toon, OB AF Matichuk, R. I. Colarco, P. R. Smith, J. A. Toon, O. B. TI Modeling the transport and optical properties of smoke plumes from South American biomass burning SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID REMOTE-SENSING OBSERVATIONS; SAHARAN DUST TRANSPORT; IMAGING SPECTRORADIOMETER; WAVELENGTH DEPENDENCE; BOUNDARY-LAYER; IN-SITU; AEROSOL; FIRE; PARTICLES; SEASON AB This study investigates the transport and optical properties of smoke plumes from South American biomass burning by using an aerosol transport and microphysical model. In general, the model can reproduce the smoke aerosol optical properties observed by satellite and ground-based instruments during the Large-Scale Biosphere-Atmosphere Experiment in Amazonia - Smoke Aerosols, Clouds, Rainfall and Climate (LBA-SMOCC) campaign. The simulated spatial distribution of smoke aerosol loading over South America also compares well to satellite observations, suggesting that the transport processes in the model are adequate over this region. The results further suggest that the emissions provided by version 2 of the Global Fire Emissions Database are too low over South America. However, wet deposition may be too aggressive in the model. Since the model wet deposition does not include the feedback smoke may have on cloud formation and precipitation suppression, too many aerosols may be removed. Surprisingly, given the different vegetation types, the model simulations also suggest that similar initial particle size distributions and aerosol optical properties can be used to simulate smoke from both African savanna and South American forest fires. However, to reproduce the observed smoke aerosol optical properties over South America, humidification of smoke aerosols needs to be considered. Model results and observations both suggest that the typical single scattering albedo of smoke over South America and Africa differ because of relative humidity, not vegetation type. Overall, this work suggests strategies for improved treatment of South American smoke plumes in climate and microphysical models. C1 [Matichuk, R. I.] NOAA, Earth Syst Res Lab, Boulder, CO 80305 USA. [Colarco, P. R.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Matichuk, R. I.; Smith, J. A.; Toon, O. B.] Univ Colorado, Atmospher & Space Phys Lab, Dept Atmospher & Ocean Sci, Boulder, CO 80309 USA. [Matichuk, R. I.] Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. RP Matichuk, RI (reprint author), NOAA, Earth Syst Res Lab, Boulder, CO 80305 USA. EM rebecca.matichuk@noaa.gov RI Colarco, Peter/D-8637-2012 OI Colarco, Peter/0000-0003-3525-1662 NR 47 TC 12 Z9 12 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 15 PY 2008 VL 113 IS D7 AR D07208 DI 10.1029/2007JD009005 PG 18 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 291MU UT WOS:000255202300003 ER PT J AU Greeley, R Whelley, PL Neakrase, LDV Arvidson, RE Bridges, NT Cabrol, NA Christensen, PR Di, K Foley, DJ Golombek, MP Herkenhoff, K Knudson, A Kuzmin, RO Li, R Michaels, T Squyres, SW Sullivan, R Thompson, SD AF Greeley, Ronald Whelley, Patrick L. Neakrase, Lynn D. V. Arvidson, Raymond E. Bridges, Nathan T. Cabrol, Nathalie A. Christensen, Philip R. Di, Kaichang Foley, Daniel J. Golombek, Matthew P. Herkenhoff, Kenneth Knudson, Amy Kuzmin, Ruslan O. Li, Ron Michaels, Timothy Squyres, Steven W. Sullivan, Robert Thompson, Shane D. TI Columbia Hills, Mars: Aeolian features seen from the ground and orbit SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID PATHFINDER LANDING SITE; GUSEV CRATER; ROUGHNESS ELEMENTS; SPIRIT ROVER; PREDICTIONS; MISSION; SYSTEM; MODEL AB Abundant wind-related features occur along Spirit's traverse into the Columbia Hills over the basaltic plains of Gusev Crater. Most of the windblown sands are probably derived from weathering of rocks within the crater, and possibly from deposits associated with Ma'adim Vallis. Windblown particles act as agents of abrasion, forming ventifacts, and are organized in places into various bed forms. Wind-related features seen from orbit, results from atmospheric models, and considerations of topography suggest that the general wind patterns and transport pathways involve: ( 1) winter nighttime winds that carry sediments from the mouth of Ma'adim Vallis into the landing site area of Spirit, where they are mixed with locally derived sediments, and ( 2) winter daytime winds that transport the sediments from the landing site southeast toward Husband Hill; similar patterns occur in the summer but with weaker winds. Reversals of daytime flow out of Gusev Crater and nighttime wind flow into the crater can account for the symmetry of the bed forms and bimodal orientations of some ventifacts. C1 [Greeley, Ronald; Whelley, Patrick L.; Neakrase, Lynn D. V.; Christensen, Philip R.; Foley, Daniel J.] Arizona State Univ, Sch Earth & Space Explorat, Tempe, AZ 85287 USA. [Cabrol, Nathalie A.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. [Bridges, Nathan T.; Golombek, Matthew P.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Arvidson, Raymond E.; Knudson, Amy] Washington Univ, St Louis, MO 63130 USA. [Di, Kaichang; Li, Ron] Ohio State Univ, Dept Civil & Environm Engn & Geodet Sci, Columbus, OH 43210 USA. [Herkenhoff, Kenneth] US Geol Survey, Flagstaff, AZ 86001 USA. [Kuzmin, Ruslan O.] Russian Acad Sci, Vernadsky Inst, Moscow 117975, Russia. [Michaels, Timothy] SW Res Inst, Dept Space Studies, Boulder, CO 80302 USA. [Squyres, Steven W.; Sullivan, Robert] Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. [Thompson, Shane D.] Univ Nevada, Dept Geol Sci, Reno, NV 89557 USA. RP Greeley, R (reprint author), Arizona State Univ, Sch Earth & Space Explorat, Box 871404, Tempe, AZ 85287 USA. EM greeley@asu.edu; pwhelley@asu.edu; neakrase@asu.edu; arvidson@wunder.wust.edu; nathan.bridges@jpl.nasa.gov; ncabrol@mail.arc.nasa.gov; phil.christensen@asu.edu; di.2@asu.edu; danhy.foley@asu.edu; mgolombek@jpl.nasa.gov; kherkenhoff@usgs.gov; knudson@wunder.wustl.edu; rok@geokhi.ru; li.282@osu.edu; tmichael@boulder.swri.edu; squyres@astro.cornell.edu; rjs33@cornell.edu; thomp102@unr.nevada.edu RI Whelley, Patrick/B-9560-2012; Bridges, Nathan/D-6341-2016 OI Whelley, Patrick/0000-0003-3266-9772; NR 56 TC 23 Z9 23 U1 2 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9097 EI 2169-9100 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD APR 15 PY 2008 VL 113 IS E6 AR E06S06 DI 10.1029/2007JE002971 PG 17 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 291NN UT WOS:000255204200001 ER PT J AU Sentlinger, GI Hook, SJ Laval, B AF Sentlinger, Gabriel I. Hook, Simon J. Laval, Bernard TI Sub-pixel water temperature estimation from thermal-infrared imagery using vectorized lake features SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE thermal-infrared imagery; sub-pixel; water temperature; satellite; unmixing ID REFLECTION RADIOMETER ASTER; IN-FLIGHT VALIDATION; SURFACE TEMPERATURE; TAHOE; CALIFORNIA; RETRIEVAL; ALGORITHM; EMISSION; MODIS; SITE AB Water skin temperature derived from thermal infrared satellite data are used in a wide variety of studies. Many of these studies would benefit from frequent, high spatial resolution (100 m pixels) thermal imagery but currently, at any given location, such data are only available every few weeks from spaceborne sensors such as ASTER. Lower spatial resolution (1 km pixels) thermal imagery is available multiple times per day at any given location, from several sensors such as MODIS on board both the AQUA and TERRA satellite platforms. In order to fully exploit lower spatial resolution imagery, a sub-pixel unmixing technique has been developed and tested at Quesnel Lake, British Columbia, Canada. This approach produces accurate, frequent high spatial resolution water skin temperature maps by exploiting a priori knowledge of water boundaries derived from vectorized water features. The pixel water-fraction maps are then input to a gradient descent algorithm to solve the mixed pixel ground leaving radiance equation for sub-pixel water temperature. Ground-leaving radiance is estimated from standard temperature and emissivity data products for pure pixels and a simple regression technique to estimate atmospheric effects. In this test case, MODIS 1 km thermal imagery was used along with 1:50,000 water features to create a high-resolution (100 m) water skin temperature map. This map is compared to a concurrent ASTER temperature image and found to be within 1 degrees C of the ASTER skin temperature 99% of the time. This is a considerable improvement over the 2.55 degrees C difference between the original MODIS product and ASTER image due to land temperature contamination. The algorithm is simple, effective, and unlocks a largely untapped resource for limnological and hydrological studies. (c) 2007 Elsevier Inc. All rights reserved. C1 [Sentlinger, Gabriel I.; Laval, Bernard] Univ British Columbia, Dept Civil Engn, Vancouver, BC V6T 1Z4, Canada. [Hook, Simon J.] CALTECH, Jet Prop Lab, Pasadena, CA USA. RP Laval, B (reprint author), Univ British Columbia, Dept Civil Engn, 6250 Appl Sci Lane, Vancouver, BC V6T 1Z4, Canada. EM blaval@civil.ube.ca RI Laval, Bernard/J-9861-2012 NR 25 TC 18 Z9 20 U1 0 U2 7 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0034-4257 EI 1879-0704 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD APR 15 PY 2008 VL 112 IS 4 BP 1678 EP 1688 DI 10.1016/j.rse.2007.08.019 PG 11 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 288BP UT WOS:000254961500032 ER PT J AU Xie, XS Liu, WT Tang, BY AF Xie, Xiaosu Liu, W. Timothy Tang, Benyang TI Spacebased estimation of moisture transport in marine atmosphere using support vector regression SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE moisture transport; water cycle; support vector regression; remote sensing ID WATER-VAPOR TRANSPORT; FIELDS; OCEAN; VARIABILITY; MACHINES; TUTORIAL; FLUX AB An improved algorithm is developed based on support vector regression (SVR) to estimate horizonal water vapor transport integrated through the depth of the atmosphere (Theta) over the global ocean from observations of surface wind-stress vector by QuikSCAT, cloud drift wind vector derived from the Multi-angle Imaging SpectroRadiometer (MISR) and geostationary satellites, and precipitable water from the Special Sensor Microwave/Imager (SSM/I). The statistical relation is established between the input parameters (the surface wind stress, the 850 mb wind, the precipitable water, time and location) and the target data (Theta calculated from rawinsondes and reanalysis of numerical weather prediction model). The results are validated with independent daily rawinsonde observations, monthly mean reanalysis data, and through regional water balance. This study clearly demonstrates the improvement of Theta derived from satellite data using SVR over previous data sets based on linear regression and neural network. The SVR methodology reduces both mean bias and standard deviation compared with rawinsonde observations. It agrees better with observations from synoptic to seasonal time scales, and compare more favorably with the reanalysis data on seasonal variations. Only the SVR result can achieve the water balance over South America. The rationale of the advantage by SVR method and the impact of adding the upper level wind will also be discussed. (c) 2007 Elsevier Inc. All rights reserved. C1 [Xie, Xiaosu; Liu, W. Timothy; Tang, Benyang] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Xie, XS (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,M-S 300 323, Pasadena, CA 91109 USA. EM xiaosu@pacific.jpl.nasa.gov NR 36 TC 16 Z9 16 U1 1 U2 4 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0034-4257 EI 1879-0704 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD APR 15 PY 2008 VL 112 IS 4 BP 1846 EP 1855 DI 10.1016/j.rse.2007.09.003 PG 10 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 288BP UT WOS:000254961500044 ER PT J AU Anderson, JE Plourde, LC Martin, ME Braswell, BH Smith, ML Dubayah, RO Hofton, MA Blair, JB AF Anderson, Jeanne E. Plourde, Lucie C. Martin, Mary E. Braswell, Bobby H. Smith, Marie-Louise Dubayah, Ralph O. Hofton, Michelle A. Blair, J. Bryan TI Integrating waveform lidar with hyperspectral imagery for inventory of a northern temperate forest SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE waveform lidar; lidar; LVIS; laser altimetry; AVIRIS; high spectral resolution imagery; hyperspectral; biomass; basal area; quadratic mean stem diameter; forest structure; height; tree species distribution ID BIOPHYSICAL PROPERTIES; IMAGING SPECTROSCOPY; MULTISPECTRAL DATA; FOOTPRINT LIDAR; TREE HEIGHT; FUSION; LASER; ACCURACY; DENSITY; AVIRIS AB It has been suggested that attempts to use remote sensing to map the spatial and structural patterns of individual tree species abundances in heterogeneous forests, such as those found in northeastern North America, may benefit from the integration of hyperspectral or multi-spectral information with other active sensor data such as lidar. Towards this end, we describe the integrated and individual capabilities of waveform lidar and hyperspectral data to estimate three common forest measurements - basal area (BA), above-ground biomass (AGBM) and quadratic mean stem diameter (QMSD) - in a northern temperate mixed conifer and deciduous forest. The use of this data to discriminate distribution and abundance patterns of five common and often, dominant tree species was also explored. Waveform lidar imagery was acquired in July 2003 over the 1000 ha. Bartlett Experimental Forest (BEF) in central New Hampshire (USA) using NASA's airborne Laser Vegetation Imaging Sensor (LVIS). High spectral resolution imagery was likewise acquired in August 2003 using NASA's Airborne Visible/Infrared Imaging Spectrometer (AVIRIS). Field data (2001-2003) from over 400 US Forest Service Northern Research Station (USFS NRS) plots were used to determine actual site conditions. Results suggest that the integrated data sets of hyperspectral and waveform lidar provide improved outcomes over use of either data set alone in evaluating common forest metrics. Across all forest conditions, 8-9% more of the variation in AGBM, BA, and QMSD was explained by use of the integrated sensor data in comparison to either AVIRIS or LVIS metrics applied singly, with estimated error 5-8% lower for these variables. Notably, in an analysis using integrated data limited to unmanaged forest tracts, AGBM coefficients of determination improved by 25% or more, while corresponding error levels decreased by over 25%. When data were restricted based on the presence of individual tree species within plots, AVIRIS data alone best predicted species-specific patterns of abundance as determined by species fraction of biomass. Nonetheless, use of LVIS and AVIRIS data - in tandem - produced complementary maps of estimated abundance and structure for individual tree species, providing a promising adjunct to traditional forest inventory and conservation biology planning efforts. (c) 2007 Elsevier Inc. All rights reserved. C1 [Anderson, Jeanne E.; Plourde, Lucie C.; Martin, Mary E.; Braswell, Bobby H.] Univ New Hampshire, Complex Syst Res Ctr, Durham, NH 03824 USA. [Smith, Marie-Louise] USDA Forest Serv, Washington, DC USA. [Dubayah, Ralph O.; Hofton, Michelle A.] Univ Maryland, Dept Geog, College Pk, MD 20742 USA. [Blair, J. Bryan] NASA, Goddard Space Flight Ctr, Washington, DC USA. RP Anderson, JE (reprint author), Univ New Hampshire, Complex Syst Res Ctr, Durham, NH 03824 USA. EM jeanne.anderson@unh.edu RI Khachadourian, Diana/C-8513-2012; Blair, James/D-3881-2013; Beckley, Matthew/D-4547-2013; Braswell, Bobby/D-6411-2016; OI Braswell, Bobby/0000-0002-4061-9516; Lepine, Lucie/0000-0003-1028-2534 NR 40 TC 101 Z9 105 U1 2 U2 50 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0034-4257 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD APR 15 PY 2008 VL 112 IS 4 BP 1856 EP 1870 DI 10.1016/j.rse.2007.09.009 PG 15 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 288BP UT WOS:000254961500045 ER PT J AU Raynolds, MK Comiso, JC Walker, DA Verbyla, D AF Raynolds, Martha K. Comiso, Josefino C. Walker, Donald A. Verbyla, David TI Relationship between satellite-derived land surface temperatures, arctic vegetation types, and NDVI SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE normalized difference vegetation index (NDVI); summer warmth index (SWI); advanced very high resolution radiometer (AVHRR); climate change; circumpolar ID NORTHERN ALASKA; TUNDRA VEGETATION; CLIMATE; TRENDS; INDEX; HETEROGENEITY; ECOSYSTEMS; RESPONSES; PLANTS; AREA AB Arctic vegetation distribution is largely controlled by climate, particularly summer temperatures. Summer temperatures have been increasing in the Arctic and this trend is expected to continue. Arctic vegetation has been shown to change in response to increases in summer temperatures, which in turn affects arctic fauna, human communities and industries. An understanding of the relationship of existing plant communities to temperature is important in order to monitor change effectively. In addition, variation along existing climate gradients can help predict where and how vegetation changes may occur as climate warming continues. In this study we described the spatial relationship between satellite-derived land surface temperature (LST), circumpolar arctic vegetation, and normalized difference vegetation index (NDVI). LST, mapped as summer warmth index (SWI), accurately portrayed temperature gradients due to latitude, elevation and distance from the coast. The SWI maps also reflected NDVI patterns, though NDVI patterns were more complex due to the effects of lakes, different substrates and different-aged glacial surfaces. We found that for the whole Arctic, a 5 degrees C increase in SWI along the climate gradient corresponded to an increase in NDVI of approximately 0.07. This result supports and is of similar magnitude as temporal studies showing increases of arctic NDVI corresponding to increases in growing season temperatures over the length of the satellite record. The strongest positive relationship between NDVI and SWI occurred in partially vegetated and graminoid vegetation types. Recently deglaciated areas, areas with many water bodies, carbonate soil areas, and high mountains had lower NDVI values than predicted by SWI. Plant growth in these areas was limited by substrate factors as well as temperature, and thus is likely to respond less to climate warming than other areas. (c) 2007 Elsevier Inc. All rights reserved. C1 [Raynolds, Martha K.; Walker, Donald A.] Univ Alaska, Inst Arctic Biol, Fairbanks, AK 99775 USA. [Comiso, Josefino C.] NASA, Goddard Space Flight Ctr, Oceans & Ice Branch, Greenbelt, MD 20771 USA. [Verbyla, David] Univ Alaska Fairbanks, Dept Nat Resource Management, Fairbanks, AK 99775 USA. RP Raynolds, MK (reprint author), Univ Alaska, Inst Arctic Biol, 311 Irving POB 757000, Fairbanks, AK 99775 USA. EM fnmkr@uaf.edu; Josefino.C.Comiso.1@gsfc.nasa.gov; ffdaw@uaf.edu; D.Verbyla@uaf.edu NR 50 TC 68 Z9 78 U1 4 U2 50 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0034-4257 EI 1879-0704 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD APR 15 PY 2008 VL 112 IS 4 BP 1884 EP 1894 DI 10.1016/j.rse.2007.09.008 PG 11 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 288BP UT WOS:000254961500047 ER PT J AU Gao, JS Daal, M Vayonakis, A Kumar, S Zmuidzinas, J Sadoulet, B Mazin, BA Day, PK Leduc, HG AF Gao, Jiansong Daal, Miguel Vayonakis, Anastasios Kumar, Shwetank Zmuidzinas, Jonas Sadoulet, Bernard Mazin, Benjamin A. Day, Peter K. Leduc, Henry G. TI Experimental evidence for a surface distribution of two-level systems in superconducting lithographed microwave resonators SO APPLIED PHYSICS LETTERS LA English DT Article ID KINETIC INDUCTANCE DETECTORS; PHOTON AB We present measurements of the temperature-dependent frequency shift of five niobium superconducting coplanar waveguide microresonators with center strip widths ranging from 3 to 50 mu m, taken at temperatures in the range of 100-800 mK, far below the 9.2 K transition temperature of niobium. These data agree well with the two-level system (TLS) theory. Fits to this theory provide information on the number of TLSs that interact with each resonator geometry. The geometrical scaling indicates a surface distribution of TLSs and the data are consistent with a TLS surface layer thickness of the order of a few nanometers, as might be expected for a native oxide layer. (c) 2008 American Institute of Physics. C1 [Gao, Jiansong; Vayonakis, Anastasios; Kumar, Shwetank; Zmuidzinas, Jonas] CALTECH, Div Phys Math & Astron, Pasadena, CA 91125 USA. [Daal, Miguel; Sadoulet, Bernard] Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. [Mazin, Benjamin A.; Day, Peter K.; Leduc, Henry G.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Gao, JS (reprint author), CALTECH, Div Phys Math & Astron, Pasadena, CA 91125 USA. EM jiansong@caltech.edu RI Mazin, Ben/B-8704-2011 OI Mazin, Ben/0000-0003-0526-1114 NR 21 TC 134 Z9 134 U1 2 U2 14 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 14 PY 2008 VL 92 IS 15 AR 152505 DI 10.1063/1.2906373 PG 3 WC Physics, Applied SC Physics GA 290IS UT WOS:000255117100058 ER PT J AU Makeev, MA Srivastava, D AF Makeev, Maxim A. Srivastava, Deepak TI Hypersonic velocity impact on a-SiC target: A diagram of damage characteristics via molecular dynamics simulations SO APPLIED PHYSICS LETTERS LA English DT Article ID CLUSTER BOMBARDMENT; PENETRATION; SOLIDS; NANOPORES; SYSTEMS AB Dynamic damage response characteristics of an amorphous silicon carbide target due to hypersonic velocity impacts of diamond projectiles are investigated using molecular dynamics simulations. In a certain range of radii of the projectile, four distinct regimes of damage are uncovered and summarized in a penetration depth diagram. The regimes correspond to shallow crater formation, deep penetration into the target, deep penetration with local melting of the target, and complete disintegration of the projectile. In the third regime, a logarithmic dependence of the penetration depth as a function of the projectile velocity has been found and explained by an analytical model. (C) 2008 American Institute of Physics. C1 [Makeev, Maxim A.; Srivastava, Deepak] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Makeev, MA (reprint author), NASA, Ames Res Ctr, Mail Stop 229-1, Moffett Field, CA 94035 USA. EM mmakeev@mail.arc.nasa.gov NR 21 TC 3 Z9 3 U1 1 U2 11 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 14 PY 2008 VL 92 IS 15 AR 151909 DI 10.1063/1.2894188 PG 3 WC Physics, Applied SC Physics GA 290IS UT WOS:000255117100030 ER PT J AU Mou, S Petschke, A Lou, Q Chuang, SL Li, JV Hill, CJ AF Mou, Shin Petschke, Adam Lou, Qi Chuang, Shun Lien Li, Jian V. Hill, Cory J. TI Midinfrared InAs/GaSb type-II superlattice interband tunneling photodetectors SO APPLIED PHYSICS LETTERS LA English DT Article ID SHORT-PERIOD SUPERLATTICES; ROOM-TEMPERATURE; DETECTORS AB A photovoltaic InAs/GaSb superlattice photodetector based on electron transfer using quantum energy levels and interband tunneling is presented: an interband tunneling detector. The quantum efficiency is about 7%, which is improved by ten times compared to the previous published interband cascade detectors. The R(0)A product is 0.03 Omega cm(2) at 200 K and is comparable to that of state-of-the-art InAs/GaSb superlattice photodiodes. Since the interband tunneling detector works without an applied bias, it is promising for small-pixel focal plane array applications. (c) 2008 American Institute of Physics. C1 [Mou, Shin; Petschke, Adam; Lou, Qi; Chuang, Shun Lien] Univ Illinois, Dept Elect & Comp Engn, Urbana, IL 61801 USA. [Li, Jian V.; Hill, Cory J.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Mou, S (reprint author), Univ Illinois, Dept Elect & Comp Engn, 1406 W Green St, Urbana, IL 61801 USA. EM s-chuang@uiuc.edu RI Li, Jian/B-1627-2016 NR 10 TC 6 Z9 6 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 EI 1077-3118 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 14 PY 2008 VL 92 IS 15 AR 153505 DI 10.1063/1.2909538 PG 3 WC Physics, Applied SC Physics GA 290IS UT WOS:000255117100110 ER PT J AU Darve, E Rodriguez-Gomez, D Pohorille, A AF Darve, Eric Rodriguez-Gomez, David Pohorille, Andrew TI Adaptive biasing force method for scalar and vector free energy calculations SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID DENSITY-OF-STATES; MOLECULAR-DYNAMICS SIMULATIONS; HISTOGRAM ANALYSIS METHOD; MONTE-CARLO METHOD; ALANINE DIPEPTIDE; CONFORMATIONAL TRANSITIONS; POTENTIAL FUNCTIONS; REACTION COORDINATE; CANONICAL ENSEMBLE; RANDOM-WALK AB In free energy calculations based on thermodynamic integration, it is necessary to compute the derivatives of the free energy as a function of one (scalar case) or several (vector case) order parameters. We derive in a compact way a general formulation for evaluating these derivatives as the average of a mean force acting on the order parameters, which involves first derivatives with respect to both Cartesian coordinates and time. This is in contrast with the previously derived formulas, which require first and second derivatives of the order parameter with respect to Cartesian coordinates. As illustrated in a concrete example, the main advantage of this new formulation is the simplicity of its use, especially for complicated order parameters. It is also straightforward to implement in a molecular dynamics code, as can be seen from the pseudocode given at the end. We further discuss how the approach based on time derivatives can be combined with the adaptive biasing force method, an enhanced sampling technique that rapidly yields uniform sampling of the order parameters, and by doing so greatly improves the efficiency of free energy calculations. Using the backbone dihedral angles Phi and Psi in N-acetylalanyl-N'-methylamide as a numerical example, we present a technique to reconstruct the free energy from its derivatives, a calculation that presents some difficulties in the vector case because of the statistical errors affecting the derivatives. (c) 2008 American Institute of Physics. C1 [Darve, Eric] Stanford Univ, Dept Mech Engn, Stanford, CA 94305 USA. [Rodriguez-Gomez, David; Pohorille, Andrew] NASA, Ames Res Ctr, Exobiol Branch, Moffett Field, CA 94035 USA. [Pohorille, Andrew] Univ Calif San Francisco, Dept Pharmaceut Chem, San Francisco, CA 94143 USA. RP Darve, E (reprint author), Stanford Univ, Dept Mech Engn, Stanford, CA 94305 USA. EM darve@stanford.edu; pohorill@max.arc.nasa.gov NR 57 TC 222 Z9 224 U1 8 U2 91 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-9606 EI 1089-7690 J9 J CHEM PHYS JI J. Chem. Phys. PD APR 14 PY 2008 VL 128 IS 14 AR 144120 DI 10.1063/1.2829861 PG 13 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 295JH UT WOS:000255470300020 PM 18412436 ER PT J AU Gutsev, GL Johnson, E Mochena, MD Bauschlicher, CW AF Gutsev, G. L. Johnson, E. Mochena, M. D. Bauschlicher, C. W., Jr. TI The structure and energetics of (GaAS)(n), (GaAs)(n)(-), and (GaAs)(n)(+) (n=2-15) SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID SMALL GAAS CLUSTERS; CONSISTENT BASIS-SETS; CONVERGENT BASIS-SETS; LMTO MD METHOD; ELECTRONIC-STRUCTURE; RELATIVISTIC PSEUDOPOTENTIALS; SEMICONDUCTOR CLUSTERS; OPTICAL-PROPERTIES; STABLE STRUCTURES; BORON NITRIDES AB Electronic and geometrical structures of neutral, negatively, and positively charged (GaAs)(n) clusters are computed using density functional theory with generalized gradient approximation. All-electron computations are performed on (GaAS)(2)-(GaAs)(9) while effective core potentials (ECPs) are used for (GaAs)(9)-(GaAs)(15). Calibration calculations on GaAs and (GaAs)(9) species support the use of the ECP for the larger clusters. The ground-state geometries of (GaAs)(n)(-) and/or (GaAs)(n)(+) are different from the corresponding neutral ground-state geometry, except for n=7, 9, 12, 14, and 15, where the neutral and ions have similar structures. Beginning with n=6, all atoms are three coordinate, except for (GaAs)(10)(+) and (GaAs)(13)(+). For the larger species, there is a competition between fullerenes built from hexagons and rhombi and geometrical configurations where Ga-Ga and As-As bonds are formed, which results in the formation of pentagons. As expected, the static polarizability varies in the order of anion > neutral > cation, but the values are rather similar for all three charge states. The thermodynamic stability for the loss of GaAs is reported. (c) 2008 American Institute of Physics. C1 [Gutsev, G. L.; Johnson, E.] Florida A&M Univ, Inst Environm Sci, Tallahassee, FL 32307 USA. [Mochena, M. D.] Florida A&M Univ, Dept Phys, Tallahassee, FL 32307 USA. [Bauschlicher, C. W., Jr.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Gutsev, GL (reprint author), Florida A&M Univ, Inst Environm Sci, Tallahassee, FL 32307 USA. EM gennady.gutsev@famu.edu NR 62 TC 30 Z9 30 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD APR 14 PY 2008 VL 128 IS 14 AR 144707 DI 10.1063/1.2884860 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 295JH UT WOS:000255470300055 PM 18412471 ER PT J AU Le Mouelic, S Paillou, P Janssen, MA Barnes, JW Rodriguez, S Sotin, C Brown, RH Baines, KH Buratti, BJ Clark, RN Crapeau, M Encrenaz, PJ Jaumann, R Geudtner, D Paganelli, F Soderblom, L Tobie, G Wall, S AF Le Mouelic, Stephane Paillou, Philippe Janssen, Michael A. Barnes, Jason W. Rodriguez, Sebastien Sotin, Christophe Brown, Robert H. Baines, Kevin H. Buratti, Bonnie J. Clark, Roger N. Crapeau, Marc Encrenaz, Pierre J. Jaumann, Ralf Geudtner, Dirk Paganelli, Flora Soderblom, Laurence Tobie, Gabriel Wall, Steve TI Mapping and interpretation of Sinlap crater on Titan using Cassini VIMS and RADAR data SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID SPECTROMETER VIMS; SURFACE ORGANICS; EJECTA; ORIGIN; VIEWS; WINDS; MELT AB Only a few impact craters have been unambiguously detected on Titan by the Cassini-Huygens mission. Among these, Sinlap is the only one that has been observed both by the RADAR and VIMS instruments. This paper describes observations at centimeter and infrared wavelengths which provide complementary information about the composition, topography, and surface roughness. Several units appear in VIMS false color composites of band ratios in the Sinlap area, suggesting compositional heterogeneities. A bright pixel possibly related to a central peak does not show significant spectral variations, indicating either that the impact site was vertically homogeneous, or that this area has been recovered by homogeneous deposits. Both VIMS ratio images and dielectric constant measurements suggest the presence of an area enriched in water ice around the main ejecta blanket. Since the Ku-band SAR may see subsurface structures at the meter scale, the difference between infrared and SAR observations can be explained by the presence of a thin layer transparent to the radar. An analogy with terrestrial craters in Libya supports this interpretation. Finally, a tentative model describes the geological history of this area prior, during, and after the impact. It involves mainly the creation of ballistic ejecta and an expanding plume of vapor triggered by the impact, followed by the redeposition of icy spherules recondensed from this vapor plume blown downwind. Subsequent evolution is then driven by erosional processes and aeolian deposition. C1 [Le Mouelic, Stephane; Tobie, Gabriel] Univ Nantes, Lab Planetol & Geodynam, F-44322 Nantes 03, France. [Janssen, Michael A.; Sotin, Christophe; Baines, Kevin H.; Buratti, Bonnie J.; Paganelli, Flora; Wall, Steve] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Barnes, Jason W.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. [Brown, Robert H.] Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. [Clark, Roger N.] US Geol Survey, Lakewood, CO 80225 USA. [Paillou, Philippe; Crapeau, Marc] Observ Aquitain Sci Univ, UMR 5804, Floirac, France. [Encrenaz, Pierre J.] Univ Paris 06, Observ Paris, F-75014 Paris, France. [Jaumann, Ralf] DLR, Inst Planetary Res, Berlin, Germany. [Rodriguez, Sebastien] Univ Paris 07, Lab AIM, Ctr Etud Saclay, DAPNIA Sap,Ctr Orme Merisiers, F-75221 Paris 05, France. [Soderblom, Laurence] US Geol Survey, Flagstaff, AZ 86001 USA. [Le Mouelic, Stephane; Tobie, Gabriel] CNRS, UMR 6112, Nantes 03, France. RP Le Mouelic, S (reprint author), Univ Nantes, Lab Planetol & Geodynam, 2 Rue Houssiniere, F-44322 Nantes 03, France. EM stephane.lemouelic@univ-nantes.fr RI Barnes, Jason/B-1284-2009; Rodriguez, Sebastien/H-5902-2016 OI Barnes, Jason/0000-0002-7755-3530; Rodriguez, Sebastien/0000-0003-1219-0641 NR 38 TC 35 Z9 35 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD APR 12 PY 2008 VL 113 IS E4 AR E04003 DI 10.1029/2007JE002965 PG 15 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 289TV UT WOS:000255077700001 ER PT J AU Farrell, WM Clifford, SM Milkovich, SM Plaut, JJ Leuschen, CJ Picardi, G Gurnett, DA Watters, TR Safaeinili, A Ivanov, AB Phillips, RJ Stofan, ER Heggy, E Cummer, SA Espley, JR AF Farrell, W. M. Clifford, S. M. Milkovich, S. M. Plaut, J. J. Leuschen, C. J. Picardi, G. Gurnett, D. A. Watters, T. R. Safaeinili, A. Ivanov, A. B. Phillips, R. J. Stofan, E. R. Heggy, E. Cummer, S. A. Espley, J. R. TI MARSIS subsurface radar investigations of the South Polar reentrant Chasma Australe SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID ORBITER LASER ALTIMETER; LAYERED DEPOSITS; IONOSPHERE; SOUNDINGS; FEATURES; BOREALE; SURFACE; ORIGIN AB The Mars Express/Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) has conducted the first-ever subsurface probing of the south polar layered deposits (SPLD) revealing internal structure that is rich in detail. We report on subsurface features detected from a set of orbits that passed over the largest of the south polar reentrants, Chasma Australe, at the edge of the SPLD. We present selected MARSIS overflights to both document the unique observations and gain insight into the possible origin of this feature. We conclude that MARSIS observations clearly reveal new evidence of subsurface structure, such as (1) internal bands, (2) the continuation of the Prometheus basin floor beneath the SPLD to form a prominent basal interface, and (3) the presence of a possible ice-rich layer on the Prometheus basin floor extending to 500-m depth. There is no obvious indication of a present-day aquifer at the head of the chasma and identification of features associated with a past aquifer and water flow is ambiguous. While MARSIS observations may not uniquely solve the chasma origin debate, they do reveal the subsurface region beneath this very interesting feature for the first time. C1 [Farrell, W. M.; Espley, J. R.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Clifford, S. M.; Heggy, E.] Lunar & Planetary Inst, Houston, TX 77058 USA. [Gurnett, D. A.] Univ Iowa, Iowa City, IA 52242 USA. [Milkovich, S. M.; Plaut, J. J.; Safaeinili, A.; Ivanov, A. B.] NASA, Jet Propuls Lab, Pasadena, CA 91109 USA. [Leuschen, C. J.] Univ Kansas, Lawrence, KS 66045 USA. [Phillips, R. J.] Washington Univ, St Louis, MO 63130 USA. [Picardi, G.] Univ Rome, Infocom Dept, I-00184 Rome, Italy. [Watters, T. R.] Smithsonian Inst, NASM, CEPS, Washington, DC 20560 USA. RP Farrell, WM (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM william.farrell@gsfc.nasa.gov RI Espley, Jared/I-5118-2013; Farrell, William/I-4865-2013; Cummer, Steven/A-6118-2008; Ivanov, Anton/C-8944-2014 OI Espley, Jared/0000-0002-6371-9683; Cummer, Steven/0000-0002-0002-0613; Ivanov, Anton/0000-0001-8376-8581 NR 21 TC 8 Z9 8 U1 1 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD APR 11 PY 2008 VL 113 IS E4 AR E04002 DI 10.1029/2007JE002974 PG 11 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 289TS UT WOS:000255077400001 ER PT J AU Zheng, YH Brandt, PC Lui, ATY Fok, MC AF Zheng, Yihua Brandt, Pontus C. Lui, Anthony T. Y. Fok, Mei-Ching TI On ionospheric trough conductance and subauroral polarization streams: Simulation results SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID RING CURRENT; ION DRIFTS; PLASMA CONVECTION; MODEL; SUBSTORM AB Subauroral polarization streams (SAPS) are usually associated with geomagnetically disturbed times and considered a manifestation of magnetosphere and ionosphere coupling. Previous research results using radar and satellite measurements have revealed many features of the SAPS events. In this paper we focus on the effects of subauroral trough conductance on the attributes of SAPS and the evolution of the coupled magnetosphere and ionosphere system through the comprehensive ring current model, which includes the coupled electrodynamics of the inner magnetosphere and ionosphere with a self-consistent description of the electric field. Our numerical analysis indicates that low conductance at the subauroral latitudes (due to midlatitude trough) is critical to the large amplitude of SAPS. The model results are generally in good agreement with common characteristics of SAPS and are consistent with their existing generation mechanism. C1 [Zheng, Yihua; Brandt, Pontus C.; Lui, Anthony T. Y.] Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. [Fok, Mei-Ching] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Zheng, YH (reprint author), Johns Hopkins Univ, Appl Phys Lab, 11100 Johns Hopkins Rd, Laurel, MD 20723 USA. EM yihua.zheng@jhuapl.edu; pontus.brandt@jhuapl.edu; tony.lui@jhuapl.edu; mei-ching.h.fok@nasa.gov RI Zheng, Yihua/D-7368-2012; Fok, Mei-Ching/D-1626-2012 NR 28 TC 18 Z9 18 U1 1 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD APR 11 PY 2008 VL 113 IS A4 AR A04209 DI 10.1029/2007JA012532 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 289UJ UT WOS:000255079100001 ER PT J AU Donati, JF Moutou, C Fares, R Bohlender, D Catala, C Deleuil, M Shkolnik, E Cameron, AC Jardine, MM Walker, GAH AF Donati, J. -F. Moutou, C. Fares, R. Bohlender, D. Catala, C. Deleuil, M. Shkolnik, E. Cameron, A. C. Jardine, M. M. Walker, G. A. H. TI Magnetic cycles of the planet-hosting star tau Bootis SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE stars : activity; stars : imaging; stars : individual : tau Boo; stars : magnetic fields; techniques : polarimetric; planetary systems ID DIFFERENTIAL ROTATION; GIANT PLANETS; ACTIVE STARS; SPECTROPOLARIMETRIC OBSERVATIONS; CHROMOSPHERIC ACTIVITY; 51 PEGASI; FIELD AB We have obtained new spectropolarimetric observations of the planet-hosting star tau Bootis, using the ESPaDOnS and NARVAL spectropolarimeters at the Canada-France-Hawaii Telescope (CFHT) and Telescope Bernard Lyot (TBL). With this data set, we are able to confirm the presence of a magnetic field at the surface of tau Boo and map its large-scale structure over the whole star. The large-scale magnetic field is found to be fairly complex, with a strength of up to 10 G; it features a dominant poloidal field and a small toroidal component, the poloidal component being significantly more complex than a dipole. The overall polarity of the magnetic field has reversed with respect to our previous observation (obtained a year before), strongly suggesting that tau Boo is undergoing magnetic cycles similar to those of the Sun. This is the first time that a global magnetic polarity switch is observed in a star other than the Sun; given the infrequent occurrence of such events in the Sun, we speculate that the magnetic cycle period of tau Boo is much shorter than that of the Sun. Our new data also allow us to confirm the presence of differential rotation, both from the shape of the line profiles and the latitudinal shearing that the magnetic structure is undergoing. The differential rotation surface shear that tau Boo experiences is found to be 6 to 10 times larger than that of the Sun, in good agreement with recent claims that differential rotation is strongest in stars with shallow convective zones. We propose that the short-magnetic cycle period is due to the strong level of differential rotation. With a rotation period of 3.0 and 3.9 d at the equator and pole, respectively, tau Boo appears as the first planet-hosting star whose rotation (at intermediate latitudes) is synchronized with the orbital motion of its giant planet (period 3.3 d). Assuming that this synchronization is not coincidental, it suggests that the tidal effects induced by the giant planet can be strong enough to force the thin convective envelope (though not the whole star) into corotation. We also detect time-dependent activity fluctuations on tau Boo, but cannot unambiguously determine whether they are intrinsic to the star or induced by the planet; more observations of similar type are needed to determine the role of the close-in giant planet orbiting tau Boo on both the activity enhancements and the magnetic cycle of the host star. C1 [Donati, J. -F.; Fares, R.] CNRS, LATT UMR 5572, F-31400 Toulouse, France. [Donati, J. -F.; Fares, R.] Univ Toulouse 3, F-31400 Toulouse, France. [Moutou, C.; Deleuil, M.] CNRS, LAM UMR 6110, F-13376 Marseille, France. [Moutou, C.; Deleuil, M.] Univ Aix Marseille 1, F-13376 Marseille, France. [Bohlender, D.] HIA NRC, Victoria, BC V9E 2E7, Canada. [Catala, C.] CNRS, LESIA UMR 8109, F-92195 Meudon, France. [Catala, C.] Univ Paris 07, F-92195 Meudon, France. [Shkolnik, E.] Univ Hawaii Manoa, NASA, Astrobiol Inst, Honolulu, HI 96822 USA. [Cameron, A. C.; Jardine, M. M.] Univ St Andrews, Sch Phys & Astron, St Andrews KY16 9SS, Fife, Scotland. RP Donati, JF (reprint author), CNRS, LATT UMR 5572, 14 Av E Belin, F-31400 Toulouse, France. EM donati@ast.obs-mip.fr; claire.moutou@oamp.fr; rim.fares@ast.obs-mip.fr; david.bohlender@nrc-cnrc.gc.ca; claude.catala@obspm.fr; magali.deleuil@oamp.fr; shkol-nik@ifa.hawaii.edu; acc4@st-andrews.ac.uk; mmj@st-andrews.ac.uk; gordonwa@uvic.ca NR 21 TC 93 Z9 93 U1 0 U2 1 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD APR 11 PY 2008 VL 385 IS 3 BP 1179 EP 1185 DI 10.1111/j.1365-2966.2008.12946.x PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 282YW UT WOS:000254604600006 ER PT J AU Brookes, MH Best, PN Peacock, JA Rottgering, HJA Dunlop, JS AF Brookes, M. H. Best, P. N. Peacock, J. A. Rottgering, H. J. A. Dunlop, J. S. TI A Combined EIS-NVSS Survey Of Radio Sources (CENSORS) - III. Spectroscopic observations SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE surveys; galaxies : active; galaxies : luminosity function, mass function; radio continuum : galaxies ID ACTIVE GALACTIC NUCLEI; K-Z RELATION; PARKES SELECTED REGIONS; STAR-FORMING GALAXIES; 7C REDSHIFT SURVEY; DIGITAL SKY SURVEY; LUMINOSITY FUNCTION; SPACE DENSITY; INFRARED OBSERVATIONS; STELLAR POPULATIONS AB The Combined EIS-NVSS Survey Of Radio Sources (CENSORS) is a 1.4-GHz radio survey selected from the NRAO VLA Sky Survey (NVSS) and complete to a flux density of 7.2 mJy. It targets the ESO Imaging Survey (EIS) Patch D, which is a 3 x 2-deg(2) field centred on 09(h)51(m)36(s).0-21 degrees 00'00 '' (J2000). This paper presents the results of spectroscopic observations of 143 of the 150 CENSORS sources. The primary motivation for these observations is to achieve sufficient spectroscopic completeness so that the sample may be used to investigate the evolution of radio sources. The observations result in secure spectroscopic redshifts for 63 per cent of the sample and likely redshifts (based on a single emission line, for example) for a further 8 per cent. Following the identification of the quasars and star-forming galaxies in the CENSORS sample, estimated redshifts are calculated for the remainder of the sample via the K - z relation for radio galaxies. Comparison of the redshift distribution of the CENSORS radio sources to distributions predicted by the various radio luminosity function evolution models of Dunlop & Peacock, results in no good match. This demonstrates that this sample can be used to expand upon previous work in that field. C1 [Brookes, M. H.; Best, P. N.; Peacock, J. A.; Dunlop, J. S.] Univ Edinburgh, Inst Astron, SUPA, Edinburgh EH9 3HJ, Midlothian, Scotland. [Brookes, M. H.] Jet Prop Lab, Pasadena, CA 91101 USA. [Rottgering, H. J. A.] Sterrewacht Leiden, NL-2300 RA Leiden, Netherlands. RP Brookes, MH (reprint author), Univ Edinburgh, Inst Astron, SUPA, Edinburgh EH9 3HJ, Midlothian, Scotland. EM pnb@roe.ac.uk NR 42 TC 33 Z9 33 U1 0 U2 3 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD APR 11 PY 2008 VL 385 IS 3 BP 1297 EP 1326 DI 10.1111/j.1365-2966.2008.12786.x PG 30 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 282YW UT WOS:000254604600015 ER PT J AU Rogers, RB Lagerloef, KPD AF Rogers, Richard B. Lagerloef, K. Peter D. TI Crystallography of ordered colloids using optical microscopy. 2. Divergent-beam technique SO APPLIED OPTICS LA English DT Article ID PHOTONIC BAND-STRUCTURE; KOSSEL LINE ANALYSIS; CRYSTALS; SUSPENSIONS; CRYSTALLIZATION; DISPERSIONS; SPHERES; STATE AB A technique has been developed to extract quantitative crystallographic data from randomly oriented colloidal crystals using a divergent-beam approach. This technique was tested on a series of diverse experimental images of colloidal crystals formed from monodisperse suspensions of sterically stabilized poly-(methyl methacrylate) spheres suspended in organic index-matching solvents. Complete sets of reciprocal lattice basis vectors were extracted in all but one case. When data extraction was successful, result 3 appeared to be accurate to about 1% for lattice parameters and to within (similar to)2 degrees for orientation. This approach is easier to implement than a previously developed parallel-beam approach with the drawback that the divergent-beam approach is not as robust in certain situations with random hexagonal close-packed crystals. The two techniques are therefore complimentary to each other, and between them it should be possible to extract quantitative crystallographic data with a conventional optical microscope from any closely index-matched colloidal crystal whose lattice parameters are compatible with visible wavelengths. (c) 2008 Optical Society of America. C1 [Rogers, Richard B.; Lagerloef, K. Peter D.] Case Western Reserve Univ, Dept Mat Sci & Engn, Cleveland, OH 44106 USA. [Rogers, Richard B.] NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Rogers, RB (reprint author), Case Western Reserve Univ, Dept Mat Sci & Engn, 10900 Euclid Ave, Cleveland, OH 44106 USA. EM richard.b.rogers@nasa.gov NR 30 TC 3 Z9 3 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD APR 10 PY 2008 VL 47 IS 11 BP 1867 EP 1879 DI 10.1364/AO.47.001867 PG 13 WC Optics SC Optics GA 295RR UT WOS:000255492100022 PM 18404186 ER PT J AU Leeuw, LL Davidson, J Dowell, CD Matthews, HE AF Leeuw, Lerothodi L. Davidson, Jacqueline Dowell, C. Darren Matthews, Henry E. TI Spatially resolved imaging at 350 mu m of cold dust in nearby elliptical galaxies SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : elliptical and lenticular, cD; galaxies : ISM; galaxies : photometry; infrared : galaxies; radio continuum : galaxies; submillimeter ID MOLECULAR GAS; INTERSTELLAR MATTER; MERGER REMNANTS; CENTAURUS-A; LUMINOSITY; KINEMATICS; NGC-3656; TAILS; SHELL; DISKS AB Continuum observations at 350 mu m of seven nearby elliptical galaxies for which CO gas disks have recently been resolved with interferometry mapping are presented. These SHARC II mapping results provide the first clearly resolved far-infrared (FIR)-to-submillimeter continuum emission from cold dust (with temperatures 31 K greater than or similar to T greater than or similar to 23 K) of any elliptical galaxy at a distance >40 Mpc. The measured FIR excess shows that the most likely and dominant heating source of this dust is not dilute stellar radiation or cooling flows, but rather star formation that could have been triggered by an accretion or merger event and fueled by dust-rich material that has settled in a dense region cospatial with the central CO gas disks. The dust is detected even in two cluster ellipticals that are deficient in H I, showing that, unlike H I, cold dust and CO in ellipticals can survive in the presence of hot X-ray gas, even in galaxy clusters. No dust cooler than 20 K, either distributed outside the CO disks or cospatial with and heated by the entire dilute stellar optical galaxy ( or very extended H I), is currently evident. C1 [Leeuw, Lerothodi L.] Rhodes Univ, Dept Phys & Elect, ZA-6140 Grahamstown, South Africa. [Leeuw, Lerothodi L.] S Africa Sq Kilometre Array MeerKAT, ZA-7405 Pinelands, South Africa. [Leeuw, Lerothodi L.] NASA, Ames Res Ctr, Space Sci & Astrophys Branch, Moffett Field, CA 94035 USA. [Davidson, Jacqueline] NASA, Ames Res Ctr, USRA SOFIA, Moffett Field, CA 94035 USA. [Dowell, C. Darren] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Matthews, Henry E.] Natl Res Council Canada, Herzberg Inst Astrophys, Penticton, BC V2A 6J9, Canada. RP Leeuw, LL (reprint author), Rhodes Univ, Dept Phys & Elect, POB 94, ZA-6140 Grahamstown, South Africa. EM lerothodi@alum.mit.edu; jdavidson@sofia.usra.edu; charles.d.dowell@jpl.nasa.gov; henry.matthews@nrc-cnrc.gc.ca NR 36 TC 13 Z9 13 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 10 PY 2008 VL 677 IS 1 BP 249 EP 261 DI 10.1086/528838 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 285CG UT WOS:000254754300017 ER PT J AU Tam, CR Gavriil, FP Dib, R Kaspi, VM Woods, PM Bassa, C AF Tam, Cindy R. Gavriil, Fotis P. Dib, Rim Kaspi, Victoria M. Woods, Peter M. Bassa, Cees TI X-ray and near-IR variability of the anomalous X-ray pulsar 1E 1048.1-5937: From quiescence back to activity SO ASTROPHYSICAL JOURNAL LA English DT Article DE pulsars : general; pulsars : individual (1E 1048.1-5937); stars : neutron ID MAGNETIZED NEUTRON-STARS; SOFT GAMMA-REPEATERS; 1E 1048.1-5937; XTE J1810-197; GIANT FLARE; 1RXS J170849.0-400910; INFRARED COUNTERPART; CYCLOTRON-RESONANCE; TRANSIENT MAGNETAR; CROSS-SECTIONS AB We report on new and archival X-ray and near-IR observations of the anomalous X-ray pulsar 1E 1048.1-5937 performed between 2001 and 2007 with the Rossi X-Ray Telescope Explorer (RXTE), the Chandra X-Ray Observatory, the Swift Gamma-Ray Burst Explorer, the Hubble Space Telescope (HST), and the Very Large Telescope. Monitoring with RXTE revealed that following its similar to 2001-2004 active period, 1E 1048.1-5937 entered a phase of timing stability; at the same time, simultaneous observations with Chandra and HST in 2006 showed that its X-ray and near-IR radiative properties, all variable prior to 2005, stabilized. Specifically, the 2006 X-ray spectrum is consistent with a two-component blackbody plus power law, with an average kt = 0.52 keV and Gamma = 2.8, at a mean flux level of similar to 6.5 x 10(-12) erg cm(-2) s(-1) (2-10 keV). The near-IR counterpart in 2005-2006 was detected at H similar to 22.7 mag and K-s similar to 21.0 mag, considerably fainter than previously measured. In 2007 March, this newfound quiescence was interrupted by sudden X-ray flux, spectral, and pulse morphology changes, simultaneous with a large glitch and near-IR enhancement. Our RXTE observations revealed a factor of similar to 3 increase in pulsed flux (2-10 keV), while observations with Chandra and Swift saw the total X-ray flux increase much more than the pulsed flux, reaching a peak value of > 7 times the quiescent value (2-10 keV). We find a strong anticorrelation between X-ray flux and pulsed fraction, and a correlation between X-ray spectral hardness and flux. Simultaneously with the radiative and timing changes, we observed the X-ray pulse profile change significantly from nearly sinusoidal to having multiple peaks. We compare these remarkable events with other magnetar outbursts and discuss implications in the context of AXP emission models. C1 [Tam, Cindy R.; Dib, Rim; Kaspi, Victoria M.; Bassa, Cees] McGill Univ, Dept Phys, Montreal, PQ H3A 2T8, Canada. [Gavriil, Fotis P.] NASA, Goddard Space Flight Ctr, Astrophys Sci Div, Greenbelt, MD 20771 USA. [Gavriil, Fotis P.] Oak Ridge Associated Univ, Oak Ridge, TN 37830 USA. [Woods, Peter M.] Dynet Inc, Huntsville, AL 35806 USA. [Woods, Peter M.] NSSTC, Huntsville, AL 35805 USA. RP Tam, CR (reprint author), McGill Univ, Dept Phys, Rutherford Phys Bldg,3600 Univ St, Montreal, PQ H3A 2T8, Canada. NR 73 TC 35 Z9 35 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 10 PY 2008 VL 677 IS 1 BP 503 EP 514 DI 10.1086/528368 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 285CG UT WOS:000254754300040 ER PT J AU Linares, M Wijnands, R van der Klis, M Krimm, H Markwardt, CB Chakrabarty, D AF Linares, Manuel Wijnands, Rudy van der Klis, Michiel Krimm, Hans Markwardt, Craig B. Chakrabarty, Deepto TI Timing and spectral properties of the accreting millisecond pulsar SWIFT J1756.9-2508 SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : close; pulsars : individual (SWIFT J1756.9-2508); stars : neutron; X-rays : binaries ID X-RAY BINARIES; QUASI-PERIODIC OSCILLATIONS; NEUTRON-STARS; RADIO PULSARS; POWER SPECTRA; VARIABILITY; DISCOVERY; PULSATIONS; FREQUENCY; EMISSION AB SWIFT J1756.9-2508 is one of the few accreting millisecond pulsars (AMPs) discovered to date. We report here the results of our analysis of its aperiodic X-ray variability, as measured with the Rossi X-Ray Timing Explorer during the 2007 outburst of the source. We detect strong (similar to 35%) flat-topped broadband noise throughout the outburst with low characteristic frequencies (similar to 0.1 Hz). This makes SWIFT J1756.9-2508 similar to the rest of AMPs and to other low-luminosity accreting neutron stars when they are in their hard states, and enables us to classify this AMP as an atoll source in the extreme island state. We also find a hard tail in its energy spectrum extending up to 100 keV, fully consistent with such source and state classification. C1 [Linares, Manuel; Wijnands, Rudy; van der Klis, Michiel] Univ Amsterdam, Astron Inst Anton Pannekoek, NL-1098 SJ Amsterdam, Netherlands. [Linares, Manuel; Wijnands, Rudy; van der Klis, Michiel] Ctr High Energy Astrophys, NL-1098 SJ Amsterdam, Netherlands. [Krimm, Hans; Markwardt, Craig B.] CRESST, Greenbelt, MD 20771 USA. [Krimm, Hans; Markwardt, Craig B.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Krimm, Hans] Univ Space Res Assoc, Columbia, MD 21044 USA. [Markwardt, Craig B.] Univ Maryland, Dept Astron, College Pk, MD 20742 USA. [Chakrabarty, Deepto] MIT, Dept Phys, Cambridge, MA 02139 USA. [Chakrabarty, Deepto] MIT, Kavli Inst Astrophys & Space Res, Cambridge, MA 02139 USA. RP Linares, M (reprint author), Univ Amsterdam, Astron Inst Anton Pannekoek, Kruislaan 403, NL-1098 SJ Amsterdam, Netherlands. NR 40 TC 10 Z9 10 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 10 PY 2008 VL 677 IS 1 BP 515 EP 519 DI 10.1086/533498 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 285CG UT WOS:000254754300041 ER PT J AU Zenitani, S Hoshino, M AF Zenitani, S. Hoshino, M. TI The role of the guide field in relativistic pair plasma reconnection SO ASTROPHYSICAL JOURNAL LA English DT Article DE acceleration of particles; instabilities; magnetic fields; plasmas; relativity ID COLLISIONLESS MAGNETIC RECONNECTION; ACTIVE GALACTIC NUCLEI; THIN CURRENT SHEETS; PARTICLE-ACCELERATION; TEARING INSTABILITIES; RADIATIVE MECHANISM; GRB OUTFLOWS; PULSAR WIND; FLUX; DISSIPATION AB We study the role of the guide field in relativistic magnetic reconnection in a Harris current sheet of pair (e(+/-)) plasmas, using linear theories and particle-in-cell (PIC) simulations. Two-dimensional PIC simulations exhibit the guide field dependence to the linear instabilities; the tearing or reconnection modes are relatively insensitive, while the relativistic drift-kink instability (RDKI), the fastest mode in a relativistic current sheet, is stabilized by the guide field. Particle acceleration in the nonlinear stage is also investigated. A three-dimensional PIC simulation demonstrates that the current sheet is unstable to the RDKI, although a small reconnection occurs in the deformed current sheet. Another three-dimensional PIC simulation with a guide field demonstrates a completely different scenario. Secondary magnetic reconnection is triggered by nonlinear coupling of oblique instabilities, which we call the relativistic drift-sausage tearing instability. Therefore, particle acceleration by relativistic guide field reconnection occurs in three-dimensional configuration. Based on the plasma theories, we discuss an important role of the guide field: to enable nonthermal particle acceleration by magnetic reconnection. C1 [Zenitani, S.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Hoshino, M.] Univ Tokyo, Dept Earth & Planetary Sci, Bunkyo Ku, Tokyo 1130033, Japan. RP Zenitani, S (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM zenitani@lssp-mail.gsfc.nasa.gov RI Zenitani, Seiji/D-7988-2013 OI Zenitani, Seiji/0000-0002-0945-1815 NR 53 TC 55 Z9 55 U1 0 U2 5 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 10 PY 2008 VL 677 IS 1 BP 530 EP 544 DI 10.1086/528708 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 285CG UT WOS:000254754300043 ER PT J AU Hillenbrand, LA Carpenter, JM Kim, JS Meyer, MR Backman, DE Moro-Martin, A Hollenbach, DJ Hines, DC Pascucci, I Bouwman, J AF Hillenbrand, Lynne A. Carpenter, John M. Kim, Jinyoung Serena Meyer, Michael R. Backman, Dana E. Moro-Martin, Amaya Hollenbach, David J. Hines, Dean C. Pascucci, Ilaria Bouwman, Jeroen TI The complete census of 70 mu m-bright debris disks within "the formation and evolution of planetary systems'' Spitzer legacy survey of sun-like stars SO ASTROPHYSICAL JOURNAL LA English DT Article DE circumstellar matter; infrared : general; Kuiper Belt; planetary systems; stars : individual ID MAIN-SEQUENCE STARS; MULTIBAND IMAGING PHOTOMETER; SOLAR-TYPE STARS; T-TAURI STARS; SPECTRAL IRRADIANCE CALIBRATION; MILLIMETER-WAVE PROPERTIES; VEGA-LIKE SYSTEMS; KUIPER-BELT; CIRCUMSTELLAR DISKS; SIZE DISTRIBUTION AB We report detection of cool dust surrounding solar-type stars from observations performed as part of the Spitzer Legacy Science Program FEPS. From a sample of 328 stars having ages similar to 0.003-3 Gyr we have selected sources with 70 mu m flux densities indicating excess in their SEDs above expected photospheric emission. Six strong excess sources are likely primordial circumstellar disks, remnants of the star formation process. Another 25 sources having >= 3 sigma excesses are associated with dusty debris disks, generated by collisions within planetesimal belts that are possibly stirred by existing planets. Six additional sources with >= 2 sigma excesses require confirmation as debris disks. In our analysis, most (> 80%) 70 mu m excess sources have >= 3 sigma excesses at 33 mu m as well, while only a minority (< 40%) have >= 3 sigma excesses at 24 mu m. The rising SEDs toward (and perhaps beyond) 70 mu m imply dust temperatures <45-85 K for debris in equilibrium with the stellar radiation field. From fitted single-temperature blackbody models we infer bulk dust properties such as characteristic temperature, location, fractional luminosity, and mass. For > 1/3 of the debris sources we find that multiple temperature components are suggested, implying a dust distribution extending over many tens of AU. Because the disks are dominated by collisional processes, the parent body (planetesimal) belts may be extended as well. Preliminary assessment of the statistics of cold debris around Sun-like stars shows that similar to 10% of FEPS targets with masses between 0.6 and 1.8m(circle dot) and ages between 30 Myr and 3 Gyr exhibit excess 70 mu m emission. We find that fractional excess amplitudes appear higher for younger stars and that there may be a trend in 70 mu m excess frequency with stellar mass. C1 [Hillenbrand, Lynne A.; Carpenter, John M.] CALTECH, Pasadena, CA 91125 USA. [Kim, Jinyoung Serena; Meyer, Michael R.; Pascucci, Ilaria] Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. [Backman, Dana E.] SOFIA SETI Inst, Mountain View, CA 94043 USA. [Moro-Martin, Amaya] Princeton Univ, Princeton, NJ 08540 USA. [Hollenbach, David J.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. [Hines, Dean C.] Space Sci Inst, Boulder, CO 80301 USA. [Bouwman, Jeroen] Max Planck Inst Astron, D-69117 Heidelberg, Germany. RP Hillenbrand, LA (reprint author), CALTECH, Pasadena, CA 91125 USA. NR 92 TC 139 Z9 140 U1 1 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 10 PY 2008 VL 677 IS 1 BP 630 EP 656 DI 10.1086/529027 PG 27 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 285CG UT WOS:000254754300051 ER PT J AU Gaelzer, R Ziebell, LF Vinas, AF Yoon, PH Ryu, CM AF Gaelzer, R. Ziebell, L. F. Vinas, A. F. Yoon, P. H. Ryu, C. -M. TI Asymmetric solar wind electron superthermal distributions SO ASTROPHYSICAL JOURNAL LA English DT Article DE interplanetary medium; solar wind ID VELOCITY DISTRIBUTION-FUNCTIONS; HELIOS PLASMA-EXPERIMENT; III RADIO-BURSTS; DISPERSION FUNCTION; GLOBAL PROCESSES; STRAHL; SPACECRAFT; CORONA; WAVES; GENERATION AB Electron distributions with various degrees of asymmetry associated with the energetic tail population are commonly detected in the solar wind near 1 AU. By numerically solving one-dimensional electrostatic weak turbulence equations the present paper demonstrates that a wide variety of asymmetric energetic tail distributions may result. It is found that a wide variety of asymmetric tail formation becomes possible if one posits that the solar wind electrons are initially composed of thermal core plus field-aligned counterstreaming beams, instead of the customary thermal population plus a single beam. It is shown that the resulting nonlinear wave-wave and wave-particle interactions lead to asymmetric nonthermal tails. It is found that the delicate difference in the average beam speeds associated with the forward versus backward components is responsible for the generation of asymmetry in the energetic tail. C1 [Gaelzer, R.] Inst Fis & Matemat, BR-96010900 Pelotas, RS, Brazil. [Ziebell, L. F.] Univ Fed Rio Grande do Sul, Inst Fis, BR-91501970 Porto Alegre, RS, Brazil. [Vinas, A. F.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Yoon, P. H.] Univ Maryland, Inst Phys Sci & Technol, College Pk, MD 20742 USA. [Ryu, C. -M.] Pohang Univ Sci & Technol, Dept Phys, Pohang, South Korea. RP Gaelzer, R (reprint author), Inst Fis & Matemat, Caixa Postal 354,Campus UFPel, BR-96010900 Pelotas, RS, Brazil. EM rudi@ufpel.edu.br RI Yoon, Peter/E-2395-2013; Ziebell, Luiz/N-7334-2014; Gaelzer, Rudi/E-4437-2013 OI Gaelzer, Rudi/0000-0001-5851-7959 NR 35 TC 23 Z9 23 U1 0 U2 4 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 10 PY 2008 VL 677 IS 1 BP 676 EP 682 DI 10.1086/527430 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 285CG UT WOS:000254754300054 ER PT J AU Brosius, JW Rabin, DM Thomas, RJ Landi, E AF Brosius, Jeffrey W. Rabin, Douglas M. Thomas, Roger J. Landi, Enrico TI Analysis of a solar coronal bright point Extreme Ultraviolet Spectrum from the EUNIS sounding rocket instrument SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : corona; Sun : magnetic fields; Sun : transition region; Sun : UV radiation ID LOOP RADIATIVE HYDRODYNAMICS; OPTICALLY THIN PLASMAS; HIGH TIME RESOLUTION; 304 ANGSTROM LINE; EMISSION-LINES; ACTIVE-REGION; CHROMOSPHERIC EVAPORATION; ATOMIC DATABASE; MAGNETIC CANCELLATION; SUN AB We present a well-calibrated EUV spectrum of a solar coronal bright point observed with the Extreme Ultraviolet Normal Incidence Spectrograph (EUNIS) sounding rocket instrument on 2006 April 12. The coronal bright point brightened around 06:30 UT during a period of emerging magnetic flux and remained bright at least until the rocket flight around 18: 12 UT, while the magnetic flux merged and canceled. Density-sensitive line intensity ratios yield mutually consistent coronal electron densities (N-e in cm(-3)) of log N-e approximate to 9.4. The differential emission measure (DEM, in cm(-5) K-1) curve derived from the spectrum yields a peak of log DEM approximate to 20.70 at log T approximate to 6,15 and a local minimum of log DEM approximate to 20.15 at log T approximate to 5.35. Photospheric (not coronal) element abundances are required to achieve equality and consistency in the DEM derived from lines of Mg V, Mg VI, Mg VII, and Ca VII (with a low first ionization potential, or FIP) and lines from Ne IV and Ne V (with a high FIP) formed at transition region temperatures. The bright point's photospheric abundance is likely produced by reconnection-driven chromospheric evaporation, a process that is not only central to existing bright point models, but also consistent with measurements of relative Doppler velocities. C1 [Brosius, Jeffrey W.] NASA, Goddard Space Flight Ctr, Catholic Univ Amer, Solar Phys Lab, Greenbelt, MD 20771 USA. [Landi, Enrico] USN, Res Lab, Artep Inc, Washington, DC 20375 USA. RP Brosius, JW (reprint author), NASA, Goddard Space Flight Ctr, Catholic Univ Amer, Solar Phys Lab, Code 671, Greenbelt, MD 20771 USA. EM jeffery.w.brosius@nasa.gov; douglas.m.rabin@nasa.gov; roger.j.thomas@nasa.gov; enrico.landi@nrl.navy.mil RI Landi, Enrico/H-4493-2011 NR 52 TC 15 Z9 16 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 10 PY 2008 VL 677 IS 1 BP 781 EP 789 DI 10.1086/528930 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 285CG UT WOS:000254754300064 ER PT J AU Sivakoff, GR Kraft, RP Jordan, A Juett, AM Evans, DA Forman, WR Hardcastle, MJ Sarazin, CL Birkinshaw, M Brassington, NJ Croston, JH Harris, WE Jones, C Murray, SS Raychaudhury, S Woodley, KA Worrall, DM AF Sivakoff, G. R. Kraft, R. P. Jordan, A. Juett, A. M. Evans, D. A. Forman, W. R. Hardcastle, M. J. Sarazin, C. L. Birkinshaw, M. Brassington, N. J. Croston, J. H. Harris, W. E. Jones, C. Murray, S. S. Raychaudhury, S. Woodley, K. A. Worrall, D. M. TI A transient black hole low-mass X-ray binary candidate in Centaurus A SO ASTROPHYSICAL JOURNAL LETTERS LA English DT Article DE binaries : close; galaxies : elliptical and lenticular; cD galaxies : individual (Centaurus A, NGC 5128); X-rays : binaries ID EARLY-TYPE GALAXIES; NGC 5128 CENTAURUS; M31; POPULATION; DISTANCES; CATALOG AB We report the discovery of a bright transient X-ray source, CXOU J132518.2-430304, toward Centaurus A (Cen A) using six new Chandra X-Ray Observatory observations in 2007 March-May. Between 2003 and 2007, its flux has increased by a factor of > 770. The source is likely a low-mass X-ray binary in Cen A with unabsorbed 0.3-10 keV band luminosities of (2-3) x 10(39)ergs s(-1) and a transition from the steep-power-law state to the thermal state during our observations. CXOU J132518.2-430304 is the most luminous X-ray source in an early-type galaxy with extensive timing information that reveals transience and a spectral state transition. Combined with its luminosity, these properties make this source one of the strongest candidates to date for containing a stellar-mass black hole in an early-type galaxy. Unless this outburst lasts many years, the rate of luminous transients in Cen A is anomalously high compared to other early-type galaxies. C1 [Sivakoff, G. R.] Ohio State Univ, Dept Astron, McPherson Lab 4055, Columbus, OH 43210 USA. [Kraft, R. P.; Jordan, A.; Evans, D. A.; Forman, W. R.; Birkinshaw, M.; Brassington, N. J.; Jones, C.; Murray, S. S.; Raychaudhury, S.; Worrall, D. M.] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. [Juett, A. M.] NASA, Goddard Space Flight Ctr, Lab Xray Lab, Greenbelt, MD 20771 USA. [Hardcastle, M. J.; Croston, J. H.] Univ Hertfordshire, Sch Phys Astron & Math, Hatfield AL10 9AB, Herts, England. [Sarazin, C. L.] Univ Virginia, Dept Astron, Charlottesville, VA 22904 USA. [Birkinshaw, M.; Worrall, D. M.] Univ Bristol, Dept Phys, Bristol BS8 ITL, Avon, England. [Harris, W. E.; Woodley, K. A.] McMaster Univ, Dept Phys & Astron, Hamilton, ON L8S 4M1, Canada. [Raychaudhury, S.] Univ Birmingham, Sch Phys & Astron, Birmingham B15 2TT, W Midlands, England. RP Sivakoff, GR (reprint author), Ohio State Univ, Dept Astron, McPherson Lab 4055, 140 W 18Th Ave, Columbus, OH 43210 USA. EM sivakoff@astronomy.ohio-state.edu RI Hardcastle, Martin/E-2264-2012; Sivakoff, Gregory/G-9602-2011 OI Hardcastle, Martin/0000-0003-4223-1117; Sivakoff, Gregory/0000-0001-6682-916X NR 26 TC 15 Z9 15 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA J9 ASTROPHYS J LETT JI Astrophys. J. Lett. PD APR 10 PY 2008 VL 677 IS 1 BP L27 EP L30 DI 10.1086/587960 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 291ZZ UT WOS:000255237400008 ER PT J AU Wilson, RJ Lewis, SR Montabone, L Smith, MD AF Wilson, R. John Lewis, Stephen R. Montabone, Luca Smith, Michael D. TI Influence of water ice clouds on Martian tropical atmospheric temperatures SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID DATA ASSIMILATION; INTERANNUAL VARIABILITY; MARS; CLIMATE; MODEL AB The Reanalysis derived from the UK Mars general circulation model assimilation of Thermal Emission Spectrometer temperature and dust opacity retrievals at present provides the best estimate of the evolving state of the Martian atmosphere over the course of the Mars Global Surveyor mapping mission. A Control simulation has also been carried out using the same evolving dust distribution as the Reanalysis, but without the temperature assimilation. Differences in zonal mean temperatures between these two simulations reflect possible biases in the representation of dynamical and radiative forcing in the assimilating model. We have identified a cold bias in the Control simulation of tropical temperature which develops in the northern hemisphere summer solstice season. We attribute this bias to the absence of radiatively active water ice clouds in the model and show that clouds likely play a prominent role in shaping the vertical thermal structure of the tropical atmosphere during this season. C1 [Wilson, R. John] Geophys Fluid Dynam Lab, Princeton, NJ 08542 USA. [Lewis, Stephen R.; Montabone, Luca] Open Univ, Dept Phys & Astron, Milton Keynes MK7 6AA, Bucks, England. [Smith, Michael D.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Wilson, RJ (reprint author), Geophys Fluid Dynam Lab, POB 308, Princeton, NJ 08542 USA. EM john.wilson@noaa.go RI Smith, Michael/C-8875-2012; OI Lewis, Stephen/0000-0001-7237-6494 NR 12 TC 47 Z9 47 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR 10 PY 2008 VL 35 IS 7 AR L07202 DI 10.1029/2007GL032405 PG 7 WC Geosciences, Multidisciplinary SC Geology GA 289SX UT WOS:000255075300001 ER PT J AU Goldstein, ME Leib, SJ AF Goldstein, M. E. Leib, S. J. TI The aeroacoustics of slowly diverging supersonic jets SO JOURNAL OF FLUID MECHANICS LA English DT Article ID HIGH-SPEED; NOISE; TURBULENCE; SOUND AB This paper is concerned with utilizing the acoustic analogy approach to predict the sound from unheated supersonic jets. Previous attempts have been unsuccessful at making such predictions over the Mach number range of practical interest. The present paper, therefore, focuses on implementing the refinements needed to accomplish this objective. The important effects influencing peak supersonic noise are found to be source convection, mean flow refraction, mean flow amplification, and source non-compactness. It appears that the last two effects have not been adequately dealt with in the literature. For the first of these this is because the usual parallel flow models produce most of the amplification in the so-called critical layer where the solution becomes singular and, therefore, causes the predicted sound field to become infinite. We deal with this by introducing a new weakly non-parallel flow analysis that eliminates the critical layer singularity. This has a strong effect on the shape of the peak noise spectrum. The last effect places severe demands on the source models at the higher Mach numbers because the retarded-time variations significantly increase the sensitivity of the radiated sound to the source structure in this case. A highly refined (non-separable) source model is, therefore, introduced in this paper. C1 [Goldstein, M. E.] NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. [Leib, S. J.] Ohio Aerosp Inst, Brookpark, OH 44135 USA. RP Goldstein, ME (reprint author), NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. NR 44 TC 28 Z9 28 U1 0 U2 2 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 32 AVENUE OF THE AMERICAS, NEW YORK, NY 10013-2473 USA SN 0022-1120 J9 J FLUID MECH JI J. Fluid Mech. PD APR 10 PY 2008 VL 600 BP 291 EP 337 DI 10.1017/S0022112008000311 PG 47 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 291NA UT WOS:000255202900015 ER PT J AU Barnes, JE Kaplan, T Vomel, H Read, WG AF Barnes, John E. Kaplan, Trevor Voemel, Holger Read, William G. TI NASA/Aura/Microwave Limb Sounder water vapor validation at Mauna Loa Observatory by Raman lidar SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID RADIOSONDES; AEROSOL; SYSTEMS AB The NASA/Aura/Microwave Limb Sounder (MLS) instrument has been compared to the Mauna Loa Observatory Raman water vapor lidar. Calibration of the lidar used Vaisala RS80-H radiosondes launched from the observatory. The average standard deviation between the sondes and the lidar, in the range 6 km to 11.5 km, is 11.9%. The sondes indicate no overlap correction for the lidar at low altitudes is necessary. A comparison was made between the lidar total column water and a GPS total column water measurement as a check on the calibration, resulting in a correlation slope of 1.026 +/- 0.058 and R-2 = 0.84. The MLS measurements are significantly better in the stratosphere where the lidar has poor sensitivity. The MLS measurement in the troposphere has much lower altitude resolution than the lidar so the validation overlap altitudes are limited. A comparison is made with version 1.5 MLS data for 32 overpasses at the three MLS altitudes in the troposphere. The GPS total column water measurement was used to screen the overpasses by eliminating ones where the water varied by more than 50% during the lidar integration period. At 147 hPa the MLS data show a dry bias of 44.8% +/- 36%. At 215 hPa the MLS measurement also shows a dry bias of 22.3% +/- 22%, and at 316 hPa there is a dry bias of 19.9% +/- 46%. The dry bias seen is consistent with the cryogenic frost point hygrometer (CFH) measurements at many latitudes (23% +/- 37% at 215 hPa and 4% +/- 62% at 316 hPa). C1 [Barnes, John E.; Kaplan, Trevor] NOAA, Mauna Loa Observ, Global Monitoring Div, Earth Syst Res Lab, Hilo, HI 96720 USA. [Read, William G.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Voemel, Holger] Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. [Voemel, Holger] NOAA, Global Monitoring Div, Earth Syst Res Lab, Boulder, CO USA. RP Barnes, JE (reprint author), NOAA, Mauna Loa Observ, Global Monitoring Div, Earth Syst Res Lab, 1437 Kilauea Ave, Hilo, HI 96720 USA. EM john.e.barnes@noaa.gov NR 19 TC 11 Z9 11 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 10 PY 2008 VL 113 IS D15 AR D15S03 DI 10.1029/2007JD008842 PG 5 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 289TG UT WOS:000255076200001 ER PT J AU Liu, HQ Pinker, RT Chin, M Holben, B Remer, L AF Liu, Hongqing Pinker, R. T. Chin, M. Holben, B. Remer, L. TI Synthesis of information on aerosol optical properties SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SINGLE-SCATTERING ALBEDO; GLOBAL RADIATION BUDGET; IMAGING SPECTRORADIOMETER; ANTHROPOGENIC AEROSOLS; TROPOSPHERIC AEROSOLS; WAVELENGTH DEPENDENCE; RETRIEVAL ALGORITHM; ABSORBING AEROSOLS; SIZE DISTRIBUTION; SULFATE AEROSOLS AB In a previous study (Liu et al., 2005) obtained are global scale estimates of aerosol optical depth at 0.55 mu m based on spatial and temporal variation patterns from models and satellite observations, regulated by the Aerosol Robotic Network (AERONET) measurements. In this study an approach is developed to obtain information on global distribution of the single scattering albedo (omega(0)), the asymmetry parameter (g), and the normalized extinction coefficient over shortwave (SW) spectrum. Since space observations of omega(0) are in early stages of development and none are available for g, first an approach was developed to infer them from relevant information from the Global Ozone Chemistry Aerosol Radiation and Transport (GOCART) model, Moderate Resolution Imaging Spectroradiometer (MODIS) and AERONET retrievals. The single scattering albedo is generated by extending GOCART omega(0) at 0.55 mu m to the entire SW spectrum using spectral dependence derived from AERONET retrievals. The asymmetry parameter over the solar spectrum is derived from the MODIS angstrom ngstrom wavelength exponent, utilizing a relationship based on AERONET almucantar observations. The normalized extinction coefficient is estimated from the MODIS angstrom ngstrom wavelength exponent. The methodology was implemented as a "proof of concept'' with one year of data. The approach described here is a step in preparedness for utilizing information from new observing systems (e. g., MISR, A-Train constellation) when available. The impact of the newly derived information on the quality of satellite based estimates of surface radiative fluxes was evaluated and is presented by Liu and Pinker (2008). C1 [Liu, Hongqing; Pinker, R. T.] Univ Maryland, Dept Atmosphere & Ocean Sci, College Pk, MD 20742 USA. [Chin, M.; Remer, L.] NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. [Holben, B.] NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Greenbelt, MD 20771 USA. RP Liu, HQ (reprint author), Univ Maryland, Dept Atmosphere & Ocean Sci, College Pk, MD 20742 USA. EM pinker@atmos.umd.edu RI Pinker, Rachel/F-6565-2010; Chin, Mian/J-8354-2012; Liu, Hongqing/F-5608-2010 OI Liu, Hongqing/0000-0002-9246-5379 NR 95 TC 14 Z9 14 U1 0 U2 9 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 10 PY 2008 VL 113 IS D7 AR D07206 DI 10.1029/2007JD008735 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 289TE UT WOS:000255076000002 ER PT J AU Inamdar, AK French, A Hook, S Vaughan, G Luckett, W AF Inamdar, Anand K. French, Andrew Hook, Simon Vaughan, Greg Luckett, William TI Land surface temperature retrieval at high spatial and temporal resolutions over the southwestern United States SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID TRACK SCANNING RADIOMETER; SATELLITE DATA; EMISSIVITY; MODIS; SPACE; TRANSPIRATION; VEGETATION; ALGORITHM; RADIATION; CLOUDS AB Land surface temperature ( LST) and its diurnal variation are important when evaluating climate change, land-atmosphere energy exchange, and the global hydrological cycle. These characteristics are observable from satellites using thermal infrared measurements, but doing so at both high spatial and temporal resolutions has been difficult. Accurate temporal and spatial knowledge of LST is critical in global-scale hydrological assimilation to improve estimates of soil moisture and evapotranspiration. Historically, satellite retrieval of global LST at high spatial resolutions ( 1 km) has relied on NOAA polar-orbiting satellites recently augmented by Moderate Resolution Imaging Spectroradiometer ( MODIS) data on board the Earth Observing System ( EOS). Each satellite instrument in a polar orbit typically provides one to two observations per day. High temporal sampling of LST is achievable with geostationary satellites but at spatial resolutions is too coarse to distinguish different land surface types ( 4-5 km) and with lower accuracy. We describe an approach which employs MODIS data as a calibration source for Geostationary Environmental Satellite ( GOES) data, then uses both data sets to yield half-hourly LST values, at 1 km spatial resolution, and returns LST with an accuracy better than 2 degrees C. The approach requires good cloud clearing, atmospheric correction, and an underlying LST model to propagate values between observations. Retrieved LST against ground truth data indicate the approach is accurate to about 2 degrees C. C1 [Inamdar, Anand K.; French, Andrew; Luckett, William] USDA, Arid Land Agr Res Ctr, Maricopa, AZ 85238 USA. [Hook, Simon; Vaughan, Greg] CALTECH, Jet Propuls Lab, Pasadena, CA 91109 USA. RP Inamdar, AK (reprint author), USDA, Arid Land Agr Res Ctr, 21881 N Cardon Lane, Maricopa, AZ 85238 USA. EM anand.inamdar@ars.usda.gov NR 36 TC 44 Z9 46 U1 2 U2 11 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 9 PY 2008 VL 113 IS D7 AR D07107 DI 10.1029/2007JD009048 PG 18 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 289TD UT WOS:000255075900006 ER PT J AU Willett, JC Le Vine, DM Idone, VP AF Willett, J. C. Le Vine, D. M. Idone, V. P. TI Lightning return stroke current waveforms aloft from measured field change, current, and channel geometry SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID TRANSMISSION-LINE MODEL; MAGNETIC-FIELDS; DART LEADERS; ELECTROMAGNETIC-RADIATION; BASE CURRENT; DERIVATIVES; SIGNATURES; AIRPLANE; RISETIME; ALABAMA AB Three-dimensional reconstructions of six rocket-triggered lightning channels are derived from stereo photographs. These reconstructed channels are used to infer the behavior of the current in return strokes above the ground from current waveforms measured at the channel base and electric field change waveforms measured at a range of 5.2 km for 24 return strokes in these channels. Streak photographs of 14 of the same strokes are analyzed to determine the risetimes, propagation speeds, and amplitudes of relative light intensity for comparison with the electrical inferences. Results include the following: ( 1) The fine structure of the field change waveforms that were radiated by these subsequent return strokes can be explained, in large part, by channel geometry. ( 2) The average 10 - 90% risetime of the stroke current increased by about a factor of seven in our sample, from an observed 0.31 +/- 0.17 ms at the surface to an inferred 2.2 +/- 0.5 ms at 1 km path length above the surface. ( 3) The three-dimensional propagation speed of the current front averaged 1.80 +/- 0.24 x 10(8) m/ s over channel lengths typically greater than 1 km. ( 4) Assuming that the measured current was entirely due to the return stroke forced an unreasonably large and abrupt reduction in inferred current amplitude over the first few tens of meters above the surface, especially in cases when the leader was bright relative to its stroke. Therefore a significant fraction of the current at the surface was probably due to the leader in such cases. ( 5) Independent of the above, peak return stroke currents decreased by approximately 37 +/- 12% between 100 m and 1 km of path length above the surface. Because of uncertainty about how to partition the measured current between leader and return stroke, however, we are unable to infer the variation of current amplitude near the ground. C1 [Le Vine, D. M.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Idone, V. P.] SUNY Albany, Dept Earth & Atmospher Sci, Albany, NY 12222 USA. RP Willett, JC (reprint author), POB 41, Garrett Pk, MD 20896 USA. EM j.c.willett@comcast.net NR 71 TC 9 Z9 9 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 9 PY 2008 VL 113 IS D7 AR D07305 DI 10.1029/2006JD008116 PG 45 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 289TD UT WOS:000255075900001 ER PT J AU Wong, S Dessler, AE Mahowald, NM Colarco, PR da Silva, A AF Wong, Sun Dessler, Andrew E. Mahowald, Natalie M. Colarco, Peter R. da Silva, Arlindo TI Long-term variability in Saharan dust transport and its link to North Atlantic sea surface temperature SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID INTERANNUAL VARIABILITY; MODEL SIMULATION; AIR LAYER; INTENSITY; INCREASE; AEROSOL AB An understanding of the atmospheric distribution of Saharan dust is crucial for understanding many Earth-system processes. We demonstrate here a model simulation indicating that the August-September dust amount in the Tropical Atlantic is linked to the basin-wide North Atlantic sea surface temperature (SST). The increasing SSTs from 1979 to 2005 are associated with a strengthening cyclonic anomaly at 700 hPa in the tropical East Atlantic, reducing Saharan dust outflow into the Tropical Atlantic at latitudes between 10 degrees-20 degrees N. A decreasing dust amount over the same region is also observed by the Advanced Very High Resolution Radiometer. Given the previously observed anti-correlation between dust and tropical cyclone (TC) activity, the long-term variation of North Atlantic SST can then directly influence TC activity by changing a TC's maximum potential intensity and indirectly by modulating the transport of the dust-laden Saharan Air Layer. C1 [Wong, Sun; Dessler, Andrew E.] Texas A&M Univ, Dept Atmospher Sci, College Stn, TX 77843 USA. [Colarco, Peter R.; da Silva, Arlindo] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Mahowald, Natalie M.] Cornell Univ, Dept Earth & Atmospher Sci, Ithaca, NY 14850 USA. RP Wong, S (reprint author), Texas A&M Univ, Dept Atmospher Sci, College Stn, TX 77843 USA. EM swong@neo.tamu.edu RI da Silva, Arlindo/D-6301-2012; Mahowald, Natalie/D-8388-2013; Dessler, Andrew/G-8852-2012; Colarco, Peter/D-8637-2012 OI da Silva, Arlindo/0000-0002-3381-4030; Mahowald, Natalie/0000-0002-2873-997X; Dessler, Andrew/0000-0003-3939-4820; Colarco, Peter/0000-0003-3525-1662 NR 27 TC 18 Z9 18 U1 0 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 EI 1944-8007 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR 8 PY 2008 VL 35 IS 7 AR L07812 DI 10.1029/2007GL032297 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 289SV UT WOS:000255075100002 ER PT J AU Dingemans, TJ Mendes, E Hinkley, JJ Weiser, ES StClair, TL AF Dingemans, Theo J. Mendes, Eduardo Hinkley, Jeffrey J. Weiser, Erik S. StClair, Terry L. TI Poly(ether imide)s from diamines with para-, meta-, and ortho-arylene substitutions: Synthesis, characterization, and liquid crystalline properties SO MACROMOLECULES LA English DT Article ID CONVENIENT METHOD; POLYIMIDE; 1,3-BIS(4-AMINOPHENOXY)BENZENE; POLYMERS; BEHAVIOR AB We have synthesized homologous series of para-, meta-, and ortho-substituted aryl ether diamine monomers, with either 2, 3, or 4 ether linkages per monomer unit, and prepared their corresponding poly(ether imide)s with 3,3',4,4'-biphenyl dianhydride (BPDA) and 3,3',4,4'-oxydiphthalic dianhydride (ODPA). All polymers were obtained in high molecular weights and gave good quality films with expected mechanical and thermal properties. The ortho- and meta-substituted diamines gave fully amorphous polymers, whereas the para-based diamines resulted in semicrystalline polymers. The glass-transition temperatures (T-g) drop in the order of para > ortho > meta, and the T, drops considerably as a function of the aryl ether content and appears to level off at four ether linkages. The T, values of our polymers were contrasted with a simple quantitative model and found to be in good agreement with the experimental results (+/- 10 degrees C). BPDA in combination with an all para-substituted, aryl ether-based diamine (BPDA-P3) forms a thermotropic liquid crystalline phase. Optical microscopy experiments confirm the presence of a nematic melt. Highly aligned films could easily be obtained by stretching the films in the liquid crystal phase, and XRD analysis of quenched films confirmed the presence of a highly aligned smectic A phase (SmA) with an order parameter < P-2 > = 0.87, indicating a high degree of molecular alignment. To the best of our knowledge, this is the first example of an all-aromatic liquid crystalline poly(ether imide). Dynamic mechanical thermal analysis (DMTA) showed that the para-aryl ethers display broad beta-transitions (25-160 degrees C), whereas the meta- and ortho-series do not show beta-transitions. All PEIs with 3 or 4 aryl ether linkages become thermoplastic in nature. The purpose of this systematic study is to provided a basic set of design rules toward the design and synthesis of all-aromatic poly(ether imide) architectures. C1 [Dingemans, Theo J.] Delft Univ Technol, Fac Aerosp Engn, NL-2629 HS Delft, Netherlands. [Mendes, Eduardo] Delft Univ Technol, Sect Nanostructured Mat, NL-2628 BL Delft, Netherlands. [Hinkley, Jeffrey J.; Weiser, Erik S.; StClair, Terry L.] NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Dingemans, TJ (reprint author), Delft Univ Technol, Fac Aerosp Engn, Kluyverweg 1, NL-2629 HS Delft, Netherlands. EM t.j.dingemans@tudelft.nl RI Dingemans, Theo/E-3532-2017; OI Mendes, Eduardo /0000-0002-7519-0668 NR 34 TC 35 Z9 35 U1 3 U2 20 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD APR 8 PY 2008 VL 41 IS 7 BP 2474 EP 2483 DI 10.1021/ma8000324 PG 10 WC Polymer Science SC Polymer Science GA 283OG UT WOS:000254645200029 ER PT J AU Allen, MS AF Allen, Marc S. TI YCC 9-NASA science goals and planning processes SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA C1 [Allen, Marc S.] NASA, Sci Mission Directorate, Washington, DC 20546 USA. EM Marc.Allen@NASA.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 9-YCC PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519XJ UT WOS:000271802801129 ER PT J AU Amashukeli, X Douglas, S Fisher, AM Grunthaner, FJ AF Amashukeli, Xenia Douglas, Susanne Fisher, Anita M. Grunthaner, Frank J. TI GEOC 69-Mechanisms of biomarker preservation and extraction from Mars-Analog mineral matrixes SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Amashukeli, Xenia; Douglas, Susanne; Fisher, Anita M.; Grunthaner, Frank J.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. EM xamashuk@jpl.nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 69-GEOC PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775105210 ER PT J AU Bonaccorsi, R AF Bonaccorsi, Rosalba TI GEOC 70-Organics-bearing phyllosilicates in hematite-rich deposits (Rio Tinto, Spain): Novel model analog for phyllosilicates outcrops on Mars SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Bonaccorsi, Rosalba] NASA, Ames Res Ctr, NPP, Space Sci & Astrobiol Div, Moffett Field, CA 94035 USA. EM rbonaccorsi@mail.arc.nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 70-GEOC PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775105199 ER PT J AU Bose, M Balk, M Ertem, G Rogoff, DA Rothschild, LJ Freund, F AF Bose, Milton Balk, Melike Ertem, Goezen Rogoff, Dana A. Rothschild, Lynn J. Freund, Fniedemann TI GEOC 214-Formation of hydrogen peroxide at the rock-water interface SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Bose, Milton] SETI Inst, Carl Sagan Ctr, Mountain View, CA 94043 USA. [Balk, Melike] Wageningen Univ, Microbiol Lab, NL-6703 HB Wageningen, Netherlands. [Ertem, Goezen] NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. [Rogoff, Dana A.] NASA, Ames Res Ctr, Code SGE, SETI Inst, Moffett Field, CA 94035 USA. EM milton.bose@gmail.com; Melike.Balk@wur.nl; ffreund@mail.arc.nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 214-GEOC PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775105145 ER PT J AU Brown, TR Hylton, D Mintz, EA Baston, J Chuang, KC AF Brown, T. Renee Hylton, Donald Mintz, Eric A. Baston, Joel Chuang, Kathy C. TI POLY 147-Investigation of reaction progress via glass transition temperature of GRC-A loaded with zeolite L SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA C1 [Brown, T. Renee; Hylton, Donald; Mintz, Eric A.; Baston, Joel] Clark Atlanta Univ, Dept Chem, Atlanta, GA 30314 USA. [Brown, T. Renee; Hylton, Donald; Mintz, Eric A.; Baston, Joel] Clark Atlanta Univ, High Performance Polymers & Composites Ctr, Atlanta, GA 30314 USA. [Chuang, Kathy C.] NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. EM trbrown77@hotmail.com NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 147-POLY PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519XJ UT WOS:000271802800705 ER PT J AU Brown, TR Hylton, D Ingram, C James, C Mintz, EA Chuang, KC AF Brown, T. Renee Hylton, Donald Ingram, Conrad James, Candace Mintz, Eric A. Chuang, Kathy C. TI POLY 36-Investigation of the dynamic melt rheology of GRC-A loaded with zeolite L SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA C1 [Brown, T. Renee; Mintz, Eric A.] Clark Atlanta Univ, Dept Chem, Atlanta, GA 30314 USA. [Brown, T. Renee; Hylton, Donald; Ingram, Conrad; James, Candace; Mintz, Eric A.] Clark Atlanta Univ, High Performance Polymers & Composites Ctr, Atlanta, GA 30314 USA. [Chuang, Kathy C.] NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. EM trbrown77@hotmail.com NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 36-POLY PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519XJ UT WOS:000271802800667 ER PT J AU Bux, SK Blair, RG Huang, CK Gogna, P Kaner, RB Fleurial, JP AF Bux, Sabah K. Blair, Richard G. Huang, Chen-Kuo Gogna, Pawan Kaner, Richard B. Fleurial, Jean-Pierre TI INOR 362-Synthesis of bulk nanostructured silicon for thermoelectric power generation applications SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Bux, Sabah K.; Kaner, Richard B.] Univ Calif Los Angeles, Dept Chem & Biochem, Los Angeles, CA 90095 USA. [Bux, Sabah K.; Kaner, Richard B.] Univ Calif Los Angeles, Calif NanoSyst Inst, Los Angeles, CA 90095 USA. [Blair, Richard G.] Univ Cent Florida, Dept Chem, Orlando, FL 32816 USA. [Huang, Chen-Kuo; Gogna, Pawan; Fleurial, Jean-Pierre] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. EM sabahkb@chem.ucla.edu; kaner@chem.ucla.edu; jean-pierre.fleurial@jpl.nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 362-INOR PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775106063 ER PT J AU Capadona, JR van den Berg, O Capadona, LA Shanmuganathan, K Tyler, DJ Rowan, SJ Weder, C AF Capadona, Jeffrey R. van den Berg, Otto Capadona, Lynn A. Shanmuganathan, Kadhir Tyler, Dustin J. Rowan, Stuart J. Weder, Christoph TI POLY 345-Do it like the sea cucumber: Bioinspired chemo-mechanical polymer nanocomposites SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA C1 [Capadona, Jeffrey R.] L Stokes Cleveland VA Med Ctr, Cleveland, OH 44106 USA. [van den Berg, Otto; Shanmuganathan, Kadhir; Rowan, Stuart J.; Weder, Christoph] Case Western Reserve Univ, Dept Macromol Sci & Engn, Cleveland, OH 44106 USA. [Capadona, Lynn A.] NASA Glenn Res Ctr, Project Orion, Vehicle Integrat Off, Cleveland, OH 44135 USA. [Tyler, Dustin J.] Case Western Reserve Univ, Dept Biomed Engn, Cleveland, OH 44106 USA. EM capadona@fes.case.edu; lynn.a.capadona@nasa.gov; dustin.tyler@case.edu RI Capadona, Jeffrey /G-4772-2010; Tyler, Dustin/C-7995-2015 OI Tyler, Dustin/0000-0002-2298-8510 NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 345-POLY PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519XJ UT WOS:000271802800292 ER PT J AU Carbaugh, AD Tyson, DS Meador, MA AF Carbaugh, Ashley D. Tyson, Daniel S. Meador, Michael A. TI CHED 685-Synthesis and chemosensory characterization of substituted anthracene bisimide derivatives SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Carbaugh, Ashley D.] Washington & Jefferson Coll, Dept Chem, Washington, PA 15301 USA. [Tyson, Daniel S.] Ohio Aerosp Inst, Mat & Struct Div, Cleveland, OH 44135 USA. [Meador, Michael A.] NASA, Glenn Res Ctr, Mat & Struct Div, Cleveland, OH 44135 USA. EM carbaughad@washjeff.edu; daniel.s.tyson@nasa.gov; Michael.A.Meador@nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 685-CHED PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775101747 ER PT J AU Freund, F Mellon, J Malhotra, R AF Freund, Friedemann Mellon, Joshua Malhotra, Ripudaman TI GEOC 102-Assembly of organic protomolecules in the seemingly forbidding matrix of magmatic minerals SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Freund, Friedemann] NASA, SETI Inst, Ames Res Ctr, Moffett Field, CA 94035 USA. [Mellon, Joshua] Oregon State Univ, Dept Phys, Corvallis, OR 97331 USA. [Malhotra, Ripudaman] SRI Int, Chem Sci & Technol Lab, Menlo Pk, CA 94025 USA. EM ffreund@mail.arc.nasa.gov; mellonj@onid.orst.edu; ripudaman.malhotra@sri.com NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 102-GEOC PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775105144 ER PT J AU Freund, FT Mellon, J Malhotra, R AF Freund, Friedemann T. Mellon, Joshua Malhotra, Ripudaman TI GEOC 213-Assembly of organic protomolecules in the seemingly forbidding matrix of magmatic minerals SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Freund, Friedemann T.] NASA, Ames Res Ctr, SETI Inst, Carl Sagan Ctr, Mountain View, CA 94043 USA. [Mellon, Joshua] Oregon State Univ, Dept Phys, Corvallis, OR 97331 USA. [Malhotra, Ripudaman] SRI Int, Chem Sci & Technol Lab, Menlo Pk, CA 94025 USA. EM ffreund@mail.arc.nasa.gov; mellonj@onid.orst.edu; ripudaman.malhotra@sri.com NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 213-GEOC PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775105055 ER PT J AU Freund, FT AF Freund, Friedemann T. TI GEOC 86-Peroxy in minerals and their role in the formation of clays SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Freund, Friedemann T.] NASA, Ames Res Ctr, SETI Inst, Carl Sagan Ctr, Mountain View, CA 94043 USA. EM ffreund@mail.arc.nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 86-GEOC PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775105053 ER PT J AU Guo, HQ Scheiman, D Nguyen, BN Meador, MA AF Guo, Haiquan Scheiman, Daniel Nguyen, Baochau N. Meador, Mary Ann TI COLL 150-Bis[3-(Triethoxysilyl)propyldisulfide] derived silica aerogel SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Guo, Haiquan; Nguyen, Baochau N.] Ohio AeroSp Inst, Cleveland, OH 44135 USA. [Scheiman, Daniel] ASRC, Cleveland, OH 44135 USA. [Meador, Mary Ann] NASA Glenn Res Ctr, Cleveland, OH 44135 USA. EM HaiquanGuo@oai.org; daniel.a.scheiman@nasa.gov; baochau.n.nguyen@nasa.gov; maryann.meador@nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 150-COLL PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775103481 ER PT J AU Hazen, RM Snellinger-O'Brien, AM Ertem, MC Johnston, MV Dworkin, JP Ertem, G AF Hazen, R. M. Snellinger-O'Brien, A. M. Ertem, M. C. Johnston, M. V. Dworkin, J. P. Ertem, Goezen TI GEOC 105-Abiotic formation of RNA-like oligomers by montmorillonite catalysis: A model study SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Hazen, R. M.] Carnegie Inst Washington, Geophys Lab, Washington, DC 20015 USA. [Snellinger-O'Brien, A. M.; Johnston, M. V.] Univ Delaware, Dept Chem & Biochem, Newark, DE 19716 USA. [Ertem, M. C.] Univ Res Fdn, Maryland Adv Dev Lab, Greenbelt, MD 20770 USA. [Dworkin, J. P.] NASA, Goddard Space Flight Ctr, Astrochem Branch, Greenbelt, MD 20771 USA. [Ertem, Goezen] NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. EM gertem@mail.arc.nasa.gov RI Dworkin, Jason/C-9417-2012 OI Dworkin, Jason/0000-0002-3961-8997 NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 105-GEOC PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775105217 ER PT J AU Heald, R AF Heald, Randy TI YCC 7-Intellectual property (IP) policy and practice of the federal government SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA C1 [Heald, Randy] NASA, Kennedy Space Ctr, FL 32899 USA. EM Randall.M.Heald@NASA.gov NR 0 TC 0 Z9 0 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 7-YCC PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519XJ UT WOS:000271802801130 ER PT J AU King, DJ Bux, SK Gogna, P Kaner, RB Fleurial, JP AF King, Daniel J. Bux, Sabah K. Gogna, Pawan Kaner, Richard B. Fleurial, Jean-Pierre TI INOR 363-Bulk nanoskutterudite for thermoelectric power generation SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [King, Daniel J.; Bux, Sabah K.; Kaner, Richard B.] Univ Calif Los Angeles, Dept Chem & Biochem, Los Angeles, CA 90095 USA. [King, Daniel J.; Bux, Sabah K.; Kaner, Richard B.] Univ Calif Los Angeles, Calif NanoSyst Inst, Los Angeles, CA 90095 USA. [Gogna, Pawan; Fleurial, Jean-Pierre] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. EM sabahkb@chem.ucla.edu; kaner@chem.ucla.edu; jean-pierre.fleurial@jpl.nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 363-INOR PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775106428 ER PT J AU Komissarov, AV Sander, SP Friedl, RR AF Komissarov, Anatoly V. Sander, Stanley P. Friedl, Randall R. TI PHYS 20-Kinetics of CH2Br and CH2BrO2 radicals in reactions with NO and O-2 SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc, Div Cellulose & Renewble Mat C1 [Komissarov, Anatoly V.] CALTECH, Jet Prop Lab, Chem Kinet & Photochem Grp, Pasadena, CA 91109 USA. [Sander, Stanley P.] CALTECH, Jet Prop Lab, Div Earth & Space Sci, Pasadena, CA 91109 USA. EM Anatoly.Komissarov@jpl.nasa.gov; ssander@jpl.nasa.gov; randall.r.friedl@jpl.nasa.gov NR 0 TC 0 Z9 0 U1 1 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 20-PHYS PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775109694 ER PT J AU Lee, TJ Huang, XC Schwenke, DW Bowman, JM AF Lee, Timothy J. Huang, Xinchuan Schwenke, David W. Bowman, Joel M. TI PHYS 705-Calculation of highly accurate rovibrational spectra for molecules containing a large-amplitude motion: Ammonia SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Lee, Timothy J.; Huang, Xinchuan; Schwenke, David W.] NASA, Ames Res Ctr, Space Sci & Astrobiol Div, Moffett Field, CA 94035 USA. [Bowman, Joel M.] Emory Univ, Cherry L Emerson Ctr Sci Computat, Atlanta, GA 30322 USA. [Bowman, Joel M.] Emory Univ, Dept Chem, Atlanta, GA 30322 USA. EM Timothy.J.Lee@nasa.gov; xhuang@mail.arc.nasa.gov; David.W.Schwenke@nasa.gov; jmbowma@emory.edu RI HUANG, XINCHUAN/A-3266-2013; schwenke, david/I-3564-2013 NR 0 TC 0 Z9 0 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 705-PHYS PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775108897 ER PT J AU Li, Q Li, YW Xie, RC Page, MA Jinks, R Marinas, BJ Mintz, EA Economy, J Shang, JK AF Li, Qi Li, Yin Wai Xie, Rong-Cai Page, Martin A. Jinks, Ryan Marinas, Benito J. Mintz, Eric A. Economy, James Shang, Jian-Ku TI ENVR 164-Palladium-modification of nitrogen-doped titanium oxide for enhanced visible-light photocatalytic activity SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Li, Qi; Li, Yin Wai; Economy, James; Shang, Jian-Ku] Univ Illinois, Dept Mat Sci & Engn, Urbana, IL 61801 USA. [Page, Martin A.; Marinas, Benito J.] Univ Illinois, Dept Civil & Environm Engn, Urbana, IL 61801 USA. [Page, Martin A.; Marinas, Benito J.] Univ Illinois, Ctr Adv Mat Purificat Water Syst, Urbana, IL 61801 USA. [Jinks, Ryan; Mintz, Eric A.] Clark Atlanta Univ, Dept Chem, Atlanta, GA 30314 USA. [Jinks, Ryan] Clark Atlanta Univ, Ctr High Performance Polymers & Composites, NASA, Atlanta, GA 30314 USA. [Mintz, Eric A.] Clark Atlanta Univ, Ctr Nanoscale Funct Mat, Atlanta, GA 30314 USA. EM qili@uiuc.edu; jkshang@uiuc.edu; rcxie@imr.ac.cn; mapage@uiuc.edu; jinks76@gmail.com; marinas@uiuc.edu; emintz@cau.edu; jeconomy@staff.uiuc.edu; jkshang@uiuc.edu RI Li, Qi/G-5248-2013 OI Li, Qi/0000-0001-9312-6793 NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 164-ENVR PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775104302 ER PT J AU Li, ZR Dervishi, E Saini, V Xu, Y Biris, AR Lupu, D Trigwell, S Biris, AS AF Li, Zhongrui Dervishi, Enkeleda Saini, Viney Xu, Yang Biris, Alexandru R. Lupu, Dan Trigwell, Steve Biris, Alexandru S. TI PHYS 486-Influences of the active species dispersion and the Fe-Co interactions on the growth of carbon nanotubes SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Li, Zhongrui; Dervishi, Enkeleda; Saini, Viney; Xu, Yang; Biris, Alexandru S.] Univ Arkansas, Dept Appl Sci, Nanotechnol Ctr, Little Rock, AR 72204 USA. [Biris, Alexandru R.; Lupu, Dan] Natl Inst Res & Dev Isotop & Mol Technol, R-3400 Cluj Napoca, Romania. [Trigwell, Steve] NASA, Electrostat & Surface Phys Lab, Kennedy Space Ctr, FL 32899 USA. EM zxli3@ualr.edu; exdervishi@ualr.edu; vxsaini@ualr.edu; yxxu@ualr.edu; biris@oc1.itim-cj.ro; lupu@oc1.itim-cj.ro; asbiris@ualr.edu RI Lupu, Dan/C-3346-2009; Biris, Alexandru /C-4517-2011 NR 0 TC 0 Z9 0 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 486-PHYS PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775109512 ER PT J AU Lin, Y Watson, KA Ghose, S Smith, JG Connell, JW AF Lin, Yi Watson, Kent A. Ghose, Sayata Smith, Joseph G., Jr. Connell, John W. TI INOR 441-Synthesis of metal nanoparticle-decorated carbon nanotubes under ambient conditions SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Lin, Yi; Smith, Joseph G., Jr.; Connell, John W.] NASA, Adv Mat & Proc Branch, Langley Res Ctr, Hampton, VA 23681 USA. [Watson, Kent A.; Ghose, Sayata] Natl Inst Aerosp, Hampton, VA 23666 USA. EM yi.lin-1@nasa.gov; kent.a.waston@nasa.gov; sayata.ghose-1@nasa.gov; joseph.g.smith@nasa.gov; john.w.connell@nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 441-INOR PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775105622 ER PT J AU Meador, MAB Nguyen, BN Vivod, SL AF Meador, Mary Ann B. Nguyen, Baochau N. Vivod, Stephanie L. TI POLY 228-Recent advances in cross-linking silica aerogels with polymers SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA C1 [Meador, Mary Ann B.; Vivod, Stephanie L.] NASA, Glenn Res Ctr, Mat & Struct Div, Cleveland, OH 44135 USA. [Nguyen, Baochau N.] Ohio Aerosp Inst, Mat & Struct Div, Cleveland, OH 44135 USA. EM maryann.meador@nasa.gov; Baochau.N.Nguyen@grc.nasa.gov; Stephanie.L.Vivod@nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 228-POLY PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519XJ UT WOS:000271802800749 ER PT J AU Meador, MA Tyson, DS Carbaugh, AD AF Meador, Michael A. Tyson, Daniel S. Carbaugh, Ashley D. TI PMSE 81-Novel aromatic diimide fluorphores SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA ID DERIVATIVES C1 [Meador, Michael A.] NASA, Glenn Res Ctr, Mat & Struct Div, Cleveland, OH 44135 USA. [Tyson, Daniel S.] Ohio Aerosp Inst, Mat & Struct Div, Cleveland, OH 44135 USA. [Carbaugh, Ashley D.] Washington & Jefferson Coll, Dept Chem, Washington, PA 15301 USA. EM Michael.A.Meador@nasa.gov; daniel.s.tyson@nasa.gov; carbaughad@washjeff.edu NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 81-PMSE PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519XJ UT WOS:000271802800067 ER PT J AU Moore, VC Conyers, JL Huff, J AF Moore, Valerie C. Conyers, Jodie L. Huff, Janice TI INOR 495-Fullerenes protect against radiation induced cellular damage SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Moore, Valerie C.] Univ Texas Hlth Sci Ctr Houston, Dept Internal Med, Houston, TX 77030 USA. [Huff, Janice] Lyndon B Johnson Space Ctr, Human Adaptat & Countermeasures Off, Houston, TX 77096 USA. EM Valerie.Moore@uth.tmc.edu; Jodie.L.Conyers@uth.tmc.edu NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 495-INOR PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775106561 ER PT J AU Nguyen, BN Meador, MAB Tousley, ME Shonkwiler, B AF Nguyen, Baochau N. Meador, Mary Ann B. Tousley, Marissa E. Shonkwiler, Brian TI POLY 509-Improving flexibility of silica-based aerogels crosslinked with polystyrene SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA C1 [Nguyen, Baochau N.] Ohio Aerosp Inst, Mat & Struct Div, Cleveland, OH 44135 USA. [Meador, Mary Ann B.] NASA, Glenn Res Ctr, Mat & Struct Div, Cleveland, OH 44135 USA. [Tousley, Marissa E.] Alfred Univ, Dept Chem, Alfred, NY 14802 USA. [Shonkwiler, Brian] Clark Atlanta Univ, Atlanta, GA 30314 USA. EM Baochau.N.Nguyen@grc.nasa.gov; maryann.meador@nasa.gov; met2@alfred.edu; bshonk@mindspring.com NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 509-POLY PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519XJ UT WOS:000271802800153 ER PT J AU Noell, AC Alconcel, LS Robichaud, DJ Okumura, M Sander, SP AF Noell, Aaron C. Alconcel, Leah S. Robichaud, D. J. Okumura, Mitchio Sander, S. P. TI PHYS 17-Near-IR kinetic spectroscopy (IRKS) of the HO2 and C2H5O2 self and cross reactions SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc, Div Cellulose & Renewble Mat C1 [Noell, Aaron C.; Robichaud, D. J.; Okumura, Mitchio] CALTECH, Arthur Amos Noyes Lab Chem Phys, Div Chem & Chem Engn, Pasadena, CA 91125 USA. [Alconcel, Leah S.] Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2BW, England. [Sander, S. P.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. EM aaron@caltech.edu; mo@its.caltech.edu; Stanley.P.Sander@jpl.nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 17-PHYS PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775108617 ER PT J AU Nuth, JA Johnson, NM Manning, S AF Nuth, Joseph A. Johnson, Natasha M. Manning, Steven TI GEOC 67-A self-perpetuating "catalyst" for the production of complex organic molecules in protostellar nebulae SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Nuth, Joseph A.; Manning, Steven] NASA, Goddard Space Flight Ctr, Astrochem Lab, Greenbelt, MD 20771 USA. [Johnson, Natasha M.] NASA Headquarters, Planetary Sci Div, Washington, DC 20546 USA. EM Joseph.A.Nuth@NASA.gov RI Johnson, Natasha/E-3093-2012; Nuth, Joseph/E-7085-2012 NR 0 TC 0 Z9 0 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 67-GEOC PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775105012 ER PT J AU Obot, E Thomas, RL Ramesh, P Ravichandran, P Ramesh, G AF Obot, Edidiong Thomas, Renard L. Ramesh, Prathyush Ravichandran, Prabakaran Ramesh, Govindarajan TI CHED 302-Bioeffects of carbon nanotubes SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Obot, Edidiong] Texas So Univ, Dept Chem, Houston, TX 77004 USA. [Thomas, Renard L.] Texas So Univ, Dept Chem, NASA, Univ Res Ctr, Houston, TX 77004 USA. [Ravichandran, Prabakaran; Ramesh, Govindarajan] Texas So Univ, Moleular Neurotoxicol Lab, Houston, TX 77004 USA. EM e_chrys13@yahoo.com; thomas_rl@tsu.edu NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 302-CHED PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775101803 ER PT J AU Okumura, M Takematsu, K Sprague, MK Mollner, AK Sander, SP Stanton, JF AF Okumura, Mitchio Takematsu, Kana Sprague, Matthew K. Mollner, Andrew K. Sander, Stanley P. Stanton, John F. TI PHYS 306-Cavity ringdown spectroscopy of atmospheric free radicals SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Okumura, Mitchio; Takematsu, Kana; Sprague, Matthew K.; Mollner, Andrew K.] CALTECH, Arthur Amos Noyes Lab Chem Phys, Div Chem & Chem Engn, Pasadena, CA 91125 USA. [Sander, Stanley P.] CALTECH, Jet Prop Lab, Div Earth & Space Sci, Pasadena, CA 91109 USA. [Stanton, John F.] Univ Texas Austin, Austin, TX 78712 USA. EM mo@its.caltech.edu; kana@caltech.edu; sprague@caltech.edu; mollner@caltech.edu; ssander@jpl.nasa.gov; stanton@jfs1.cm.utexas.edu NR 0 TC 0 Z9 0 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 306-PHYS PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775109674 ER PT J AU Robichaud, D Hodges, JT Brown, LR Lisak, D Maslowski, P Yeung, LY Miller, CE Okumura, M AF Robichaud, David Hodges, Joseph T. Brown, Linda R. Lisak, Daniel Maslowski, Piotr Yeung, Laurence Y. Miller, Charles E. Okumura, Mitchio TI PHYS 108-Frequency-stabilized cavity ringdown spectroscopy of the oxygen A-band spectrum SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Robichaud, David; Yeung, Laurence Y.; Okumura, Mitchio] CALTECH, Arthur Amos Noyes Lab Chem Phys, Div Chem & Chem Engn, Pasadena, CA 91125 USA. [Hodges, Joseph T.] Natl Inst Stand, Proc Measurements Div, Gaithersburg, MD 20899 USA. [Brown, Linda R.; Miller, Charles E.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. [Lisak, Daniel; Maslowski, Piotr] Uniwesytet Mikolaja Kopernika, Intytut Fisyki, PL-87100 Torun, Poland. EM djr@caltech.edu; pima@fizyka.umk.pl; lyeung@caltech.edu; charles.e.miller@jpl.nasa.gov; mo@its.caltech.edu RI Lisak, Daniel/E-1470-2014; Maslowski, Piotr/H-4476-2014 OI Maslowski, Piotr/0000-0001-8882-7106 NR 0 TC 0 Z9 0 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 108-PHYS PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775109714 ER PT J AU Russell, M AF Russell, Michael TI CHED 758-Energy supplies for the origin of life SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Russell, Michael] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. EM Michael.J.Russell@jpl.nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 758-CHED PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775103200 ER PT J AU Scott, RL Tatum-Gibbs, K Phan, T Thomas, RL Wilson, BL AF Scott, Reba L. Tatum-Gibbs, Katoria Phan, Taun Thomas, Renard L. Wilson, Bobby L. TI CHED 1121-Preliminary characterization of environmental estrogens in wastewater effluents SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Tatum-Gibbs, Katoria] Texas So Univ, Dept Chem, Environm Toxicol PhD Program, Houston, TX 77004 USA. [Phan, Taun; Thomas, Renard L.; Wilson, Bobby L.] Texas So Univ, NASA, Dept Chem, Univ Res Ctr, Houston, TX 77004 USA. EM rlscott32@yahoo.com; thomas_rl@tsu.edu; wilson_bl@tsu.edu NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 1121-CHED PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775101869 ER PT J AU Smith, TM Williams, MK Fesmire, JE Sass, JP Weiser, ES AF Smith, Trent M. Williams, Martha K. Fesmire, James E. Sass, Jared P. Weiser, Erik S. TI PMSE 433-Fire and engineering properties of polyimide - aerogel hybrid foam composites for advanced applications SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Smith, Trent M.; Williams, Martha K.; Fesmire, James E.; Sass, Jared P.] NASA, John F Kennedy Space Ctr, Spaceport Technol Div, Kennedy Space Ctr, FL 32899 USA. [Weiser, Erik S.] NASA, Langley Res Ctr, Adv Mat & Proc Branch, Hampton, VA 23681 USA. EM Trent.M.Smith@nasa.gov; martha.k.williams@nasa.gov; James.E.Fesmire@nasa.gov; Jared.P.Sass@nasa.gov; Erik.S.Weiser@nasa.gov NR 0 TC 0 Z9 0 U1 1 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 433-PMSE PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775109277 ER PT J AU Tchoul, MN Ford, WT Sumarriva, IJC Grady, BP Resasco, DE Arepalli, S AF Tchoul, Maxim N. Ford, Warren T. Sumarriva, Israel J. Chavez Grady, Brian P. Resasco, Daniel E. Arepalli, Sivaram TI PMSE 346-Dispersion of single-walled carbon nanotubes in polystyrene with the aid of a semiconjugated polymer SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Tchoul, Maxim N.; Ford, Warren T.] Oklahoma State Univ, Dept Chem, Stillwater, OK 74078 USA. [Sumarriva, Israel J. Chavez; Grady, Brian P.; Resasco, Daniel E.] Univ Oklahoma, Sch Chem Biol & Mat Engn, Norman, OK 73019 USA. [Arepalli, Sivaram] NASA, ERC Inc, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. EM maxim.tchoul@okstate.edu; warren.ford@okstate.edu; bpgrady@ou.edu; resasco@ou.edu; sivaram.arepalli1@jsc.nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 346-PMSE PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775109079 ER PT J AU Tolbert, MA Trainer, MG Hasenkopf, CA Jimenez, JL Pavlov, AA McKay, CP Toon, OB AF Tolbert, Margaret A. Trainer, Melissa G. Hasenkopf, Christa A. Jimenez, Jose L. Pavlov, Alex A. McKay, Christopher P. Toon, Owen B. TI PHYS 195-A tale of two worlds: Organic aerosols in the atmospheres of Titan and early Earth SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Tolbert, Margaret A.; Trainer, Melissa G.; Jimenez, Jose L.] Univ Colorado, Dept Chem & Biochem, Boulder, CO 80309 USA. [Trainer, Melissa G.] Univ Colorado, CIRES, CIRES 318, UCB 216, Boulder, CO 80309 USA. [Hasenkopf, Christa A.; Toon, Owen B.] Univ Colorado, Dept Atmospher & Ocean Sci, Boulder, CO 80309 USA. [Toon, Owen B.] Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80309 USA. [Pavlov, Alex A.] Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. [McKay, Christopher P.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. EM tolbert@colorado.edu; melissa.trainer@colorado.edu RI Jimenez, Jose/A-5294-2008 OI Jimenez, Jose/0000-0001-6203-1847 NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 195-PHYS PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775108855 ER PT J AU Tolbert, MA Trainer, MG Gough, RV McKay, CP Toon, OB AF Tolbert, Margaret A. Trainer, Melissa G. Gough, Raina V. McKay, Christopher P. Toon, Owen B. TI COLL 321-Laboratory studies of interfacial processes on Mars: The methane mystery SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Tolbert, Margaret A.; Trainer, Melissa G.; Gough, Raina V.] Univ Colorado, Dept Chem & Biochem, Boulder, CO 80309 USA. [Tolbert, Margaret A.; Trainer, Melissa G.; Gough, Raina V.] Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. [McKay, Christopher P.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. [Toon, Owen B.] Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80309 USA. [Toon, Owen B.] Univ Colorado, Dept Atmospher & Ocean Sci, Boulder, CO 80309 USA. EM tolbert@colorado.edu; melissa.trainer@colorado.edu NR 0 TC 0 Z9 0 U1 1 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 321-COLL PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775103446 ER PT J AU Trainer, MG Jensen, EJ Toon, OB Tolbert, MA AF Trainer, Melissa G. Jensen, Eric J. Toon, Owen B. Tolbert, Margaret A. TI COLL 271-New measurements of high supersaturations to shape understanding of ice cloud nucleation SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Trainer, Melissa G.] Univ Colorado, LASP, Boulder, CO 80309 USA. [Trainer, Melissa G.] Univ Colorado, CIRES, Boulder, CO 80309 USA. [Jensen, Eric J.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. [Toon, Owen B.] Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80309 USA. [Toon, Owen B.] Univ Colorado, Dept Atmospher & Ocean Sci, Boulder, CO 80309 USA. [Tolbert, Margaret A.] Univ Colorado, Dept Chem & Biochem, Boulder, CO 80309 USA. EM trainer@lasp.colorado.edu; tolbert@spot.colorado.edu NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 271-COLL PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775103572 ER PT J AU Travis, SS Ferrante, RF Moore, MH AF Travis, Samuel S. Ferrante, Robert F. Moore, Marla H. TI PHYS 381-Low temperature spectroscopic studies of acetylene-water ices relevant to astrophysical environments SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Travis, Samuel S.; Ferrante, Robert F.] USN Acad, Dept Chem, Annapolis, MD 21402 USA. [Moore, Marla H.] NASA, Goddard Space Flight Ctr, Astrochem Branch, Greenbelt, MD 20771 USA. EM m086756@usna.edu; ferrante@usna.edu; Marla.H.Moore@nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 381-PHYS PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775108842 ER PT J AU Tyson, DS Aschenbener, JR Ilhan, F Meador, MA AF Tyson, Daniel S. Aschenbener, Justin R. Ilhan, Faysal Meador, Michael A. TI ORGN 185-1-Substituted 2,3-naphthalimides: Synthesis and optical properties SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Meador, Michael A.] NASA, Glenn Res Ctr, Mat & Struct Div, Cleveland, OH 44135 USA. [Tyson, Daniel S.] Ohio Aerosp Inst, Mat & Struct Div, Cleveland, OH 44135 USA. [Aschenbener, Justin R.] Univ Chicago, Chicago, IL 60637 USA. [Ilhan, Faysal] Abu Dhabi Univ, Dept Nat Sci & Chem, Abu Dhabi, U Arab Emirates. EM daniel.s.tyson@nasa.gov; aschenbener@UChicago.edu; ulvi.ilhan@abu.ac.ae; Michael.A.Meador@nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 185-ORGN PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775107488 ER PT J AU Van Wyngarden, AL Michelsen, RRH Iraci, LT AF Van Wyngarden, Annalise L. Michelsen, Rebecca R. H. Iraci, Laura T. TI PHYS 641-Changes in the chemical speciation of methylglyoxal in atmospheric aerosols during cloud cycling: Kinetic vs. equilibrium control SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Van Wyngarden, Annalise L.] NASA, Atmospher Sci Branch, Ames Res Ctr, Moffett Field, CA 94035 USA. [Michelsen, Rebecca R. H.] Randolph Macon Coll, Dept Chem, Ashland, VA 23005 USA. [Iraci, Laura T.] NASA, Div Earth Sci, Ames Res Ctr, Moffett Field, CA 94035 USA. EM avanwyngarden@arc.nasa.gov; rmichelsen@rmc.edu; laura.t.iraci@nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 641-PHYS PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775109358 ER PT J AU Vander Wal, RL Hunter, GW Berger, GM Xu, JC Evans, LJ AF Vander Wal, Randy L. Hunter, Gary W. Berger, Gordon M. Xu, Jennifer C. Evans, Laura J. TI INOR 68-Synthesis and integration of metal oxide nanostructures for combustion and environmental monitoring SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA SP Amer Chem Soc C1 [Vander Wal, Randy L.; Berger, Gordon M.] NASA Glen, Nanotechnol Lab, NCSER, Cleveland, OH 44135 USA. [Hunter, Gary W.; Evans, Laura J.] NASA Glenn Res Ctr, Sensors & Elect Branch, Cleveland, OH 44135 USA. EM randy@rvander.grc.nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 68-INOR PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519OA UT WOS:000271775106148 ER PT J AU Vivod, SL Meador, MAB Capadona, LA Sullivan, RM Ghosn, LJ Quade, DJ McCorkle, L Clark, N AF Vivod, Stephanie L. Meador, Mary Ann B. Capadona, Lynn A. Sullivan, Roy M. Ghosn, Louis J. Quade, Derek J. McCorkle, Linda Clark, Nicholas TI POLY 500-Carbon nanofiber incorporated silica based aerogels with di-isocyanate cross-linking SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract CT 235th American-Chemical-Society National Meeting CY APR 06-10, 2008 CL New Orleans, LA C1 [Vivod, Stephanie L.; Meador, Mary Ann B.; Sullivan, Roy M.; Ghosn, Louis J.; Quade, Derek J.; McCorkle, Linda; Clark, Nicholas] NASA, Glenn Res Ctr, Mat & Struct Div, Cleveland, OH 44135 USA. [Capadona, Lynn A.] NASA, Glenn Res Ctr, Vehicle Integrat Off, Project Orion, Cleveland, OH 44135 USA. EM Stephanie.L.Vivod@nasa.gov; maryann.meador@nasa.gov; lynn.a.capadona@nasa.gov; roy.m.sullivan@nasa.gov NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 6 PY 2008 VL 235 MA 500-POLY PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 519XJ UT WOS:000271802800149 ER PT J AU Oieroset, M Phan, TD Fairfield, DH Raeder, J Gosling, JT Drake, JF Lin, RP AF Oieroset, M. Phan, T. D. Fairfield, D. H. Raeder, J. Gosling, J. T. Drake, J. F. Lin, R. P. TI The existence and properties of the distant magnetotail during 32 hours of strongly northward interplanetary magnetic field SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID ELECTRON HEAT-FLUX; POLAR RAIN; ISEE-3; TAIL; LONG; MAGNETOSPHERE; IMF AB We report observations made by the Wind spacecraft in the distant magnetotail on 22-24 October 2003 when the interplanetary magnetic field ( IMF) was strongly northward for more than 32 h. A well-defined magnetotail was observed down to at least X(GSM) = - 125 RE even after 32 h of strongly northward IMF conditions. However, the observed tail properties were strikingly different from the typical magnetotail. Although the closed field line plasma sheet was observed throughout the northward IMF interval, the usual mantle/lobe disappeared one hour after the northward IMF front reached the frontside magnetopause. Instead, open field lines were observed populated by field-aligned solar wind strahl electrons as well as plasma sheet electrons predominantly at 90 degrees pitch angle. In essence, these observations provide evidence for reconnection between the IMF and a previously closed nightside cold dense plasma sheet during long periods of northward IMF, after poleward-of-the-cusp reconnection has depleted all open lobe field lines. C1 [Oieroset, M.; Phan, T. D.; Lin, R. P.] Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. [Fairfield, D. H.] NASA, Goddard Space Flight Ctr, Lab Solar & Space Phys, Greenbelt, MD 20771 USA. [Raeder, J.] Univ New Hampshire, Dept Phys & Space Sci Ctr, Durham, NH 03824 USA. [Gosling, J. T.] Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80303 USA. [Drake, J. F.] Univ Maryland, College Pk, MD 20742 USA. RP Oieroset, M (reprint author), Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. EM oieroset@ssl.berkeley.edu; phan@ssl.berkeley.edu; donald.fairfield@nasa.gov; j.raeder@unh.edu; jack.gosling@lasp.colorado.edu; drake@plasma.umd.edu; rlin@ssl.berkeley.edu NR 21 TC 6 Z9 7 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD APR 5 PY 2008 VL 113 IS A4 AR A04206 DI 10.1029/2007JA012679 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 284PQ UT WOS:000254718700001 ER PT J AU Namboothiri, SP Jiang, JH Kishore, P Igarashi, K Ao, CO Romans, LJ AF Namboothiri, S. P. Jiang, J. H. Kishore, P. Igarashi, K. Ao, C. O. Romans, L. J. TI CHAMP observations of global gravity wave fields in the troposphere and stratosphere SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID GPS RADIO OCCULTATION; MESOSCALE VARIABILITY; ATMOSPHERIC MOTIONS; SPECTRUM; MORPHOLOGY; CLIMATOLOGY; EXCITATION; SATELLITE; VARIANCE; GPS/MET AB This paper presents the analysis of 56 months of CHAMP (Challenging Minisatellite Payload) RO (radio occultation) temperature profiles to study the global gravity wave fields in the troposphere and lower stratosphere. The relatively new GPS (Global Positioning System) RO technique is suitable for global monitoring and provides high vertical resolution, long-term stability, and opportunity of all-weather viewing. The CHAMP data set analyzed in this paper is the largest RO data set used for the investigation of global structure of gravity waves. The analysis also makes use of the global radiosonde data provided by the British Atmospheric Data Centre (BADC). First, the global winter temperature pattern and temperature fluctuations in the troposphere and lower stratosphere are discussed. The global structure of gravity wave variances in the upper troposphere and lower stratosphere for the summer and winter seasons indicate the dominance in the tropical region. The analysis reveals that the maximum potential energy (E-p) is observed around the equator with considerable longitudinal variation. Comparison of the wave energy derived from the CHAMP and radiosonde data sets for the low-latitude region (20 degrees S-20 degrees N) shows good similarity. The observed vertical wave number power spectra were compared with a model spectrum. The low-latitude power spectra show considerable similarities with the model spectrum. However, the disparity increases in the midlatitude or high-latitude sectors; particularly, in the high latitudes the observed spectral power is much underestimated for longer wavelengths. The results demonstrate the usefulness of GPS RO data in determining the global gravity wave fields. C1 [Namboothiri, S. P.; Igarashi, K.] Natl Inst Informat & Commun Technol, Tokyo 1848795, Japan. [Jiang, J. H.; Ao, C. O.; Romans, L. J.] Jet Propuls Lab, Pasadena, CA 91109 USA. [Kishore, P.] Dalhousie Univ, Dept Phys & Atmospher Sci, Halifax, NS B3H 3J5, Canada. RP Namboothiri, SP (reprint author), Natl Inst Informat & Commun Technol, 4-2-1 Nukui Kita, Tokyo 1848795, Japan. EM nambooth@nict.go.jp NR 38 TC 9 Z9 9 U1 3 U2 10 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 4 PY 2008 VL 113 IS D7 AR D07102 DI 10.1029/2007JD008912 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 284OZ UT WOS:000254717000003 ER PT J AU Kessel, RL AF Kessel, R. L. TI Solar wind excitation of Pc5 fluctuations in the magnetosphere and on the ground SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID FIELD LINE RESONANCES; UPSTREAM PRESSURE VARIATIONS; PERIOD MAGNETIC PULSATIONS; CORONAL MASS EJECTIONS; WAVE-GUIDE MODES; ULF WAVES; EARTHS MAGNETOSPHERE; MAGNETOPAUSE; POWER; MAGNETOSHEATH AB The primary purpose of this paper is to show the importance of solar wind excitation as a source of magnetospheric and ground Pc5 fluctuations. In particular, we show that pressure fluctuations, a nearly ubiquitous feature of the solar wind, drive magnetospheric compressional Pc5, whose amplitude and power increase in direct proportion to the amplitude and power of the solar wind pressure fluctuations. Previous studies of compressional Pc5 have focused primarily on internally generated waves on the dusk flank; here we highlight the pressure fluctuations associated with geoeffective high-speed streams ( HSSs) and interplanetary coronal mass ejections ( ICMEs) during a time interval in March and April 2002, in the declining phase of the solar cycle, when there was a favorable alignment of satellites. Using three examples and a statistical survey, we show that for this time interval external forcing due to solar wind dynamic pressure fluctuations was dominant over internal forcing. Fluctuations driven by internal processes, occurring primarily at dusk and on the nightside, accounted for less than 20% of the total power. We also found that multiple external forcing processes were occurring during this interval, including evanescent propagation of compressional waves, field line resonance ( FLR), and global mode excitation. We need to enlarge our vision of the source of ULF waves to include excitation by solar wind pressure fluctuations as a significant factor. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Kessel, RL (reprint author), NASA, Goddard Space Flight Ctr, Code 661, Greenbelt, MD 20771 USA. EM mona.kessel@nasa.gov NR 47 TC 26 Z9 26 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD APR 3 PY 2008 VL 113 IS A4 AR A04202 DI 10.1029/2007JA012255 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 284PP UT WOS:000254718600001 ER PT J AU Grugel, RN Luz, P Smith, G Spivey, R Jeter, L Gillies, D Hua, F Anilkumar, AV AF Grugel, Richard N. Luz, Paul Smith, Guy Spivey, Reggie Jeter, Linda Gillies, Donald Hua, Fay Anilkumar, A. V. TI Materials research conducted aboard the International Space Station: Facilities overview, operational procedures, and experimental outcomes SO ACTA ASTRONAUTICA LA English DT Article ID DENDRITIC GROWTH AB The Microgravity Science Glovebox (MSG) and Maintenance Work Area (MWA) are facilities aboard the International Space Station (ISS) have been successfully used to conduct experiments in support of, respectively, the Pore Formation and Mobility Investigation (PFMI) and the In-Space Soldering Investigation (ISSI). The capabilities of these facilities are briefly discussed and then demonstrated by presenting "real-time" and subsequently down linked video-taped examples from the abovementioned experiments. Data interpretation, ISS telescience, some lessons learned, and the need of such facilities for conducting work in support of understanding materials' behavior, particularly fluid processing and transport scenarios, in low-gravity environments, is discussed. (c) 2008 Elsevier Ltd. All rights reserved. C1 [Grugel, Richard N.; Luz, Paul; Jeter, Linda; Gillies, Donald] NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. [Hua, Fay] Intel Corp, Santa Clara, CA 95051 USA. [Anilkumar, A. V.] Vanderbilt Univ, Nashville, TN 37203 USA. RP Grugel, RN (reprint author), NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. EM richard.n.grugel@nasa.gov; paul.luz@nasa.gov; gsmith@tecmasters.com; reggie.a.spivey@nasa.gov; linda.bjeter@nasa.gov; Donald.C.Gillies@nasa.gov; fay.hua@intel.com; anil@vuse.vanderbilt.edu NR 4 TC 1 Z9 1 U1 1 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0094-5765 J9 ACTA ASTRONAUT JI Acta Astronaut. PD APR-MAY PY 2008 VL 62 IS 8-9 BP 491 EP 498 DI 10.1016/j.actaastro.2008.01.013 PG 8 WC Engineering, Aerospace SC Engineering GA 294ZP UT WOS:000255445100004 ER PT J AU Dick, S AF Dick, Steven TI The postbiological universe SO ACTA ASTRONAUTICA LA English DT Article ID CIVILIZATIONS AB The Drake Equation for the number of radio communicative technological civilizations in the Galaxy encompasses three components of cosmic evolution: astronomical, biological and cultural. Of these three, cultural evolution totally dominates in terms of the rapidity of its effects. Yet, SETI scientists do not take cultural evolution into account, perhaps for understandable reasons, since cultural evolution is not well-understood even on Earth and is unpredictable in its outcome. Thus SETI programs typically assume the existence of flesh-and-blood intelligence considerably older than our civilization, a paradigm part of what I have termed the biological universe [S.J. Dick, The Biological Universe: The Twentieth Century Extraterrestrial Life Debate and the Limits of Science, Cambridge University Press, Cambridge, 1996]. Yet, the one certainty for technical civilizations billions, millions, or even thousands of years older than ours is that they will have undergone cultural evolution. Cultural evolution takes place in many directions, but in sorting priorities I adopt what I refer to as the Intelligence Principle: the maintenance, improvement and perpetuation of knowledge and intelligence is the central driving force of cultural evolution, and that to the extent intelligence can be improved, it will be improved. Applying this principle to life in the universe, extraterrestrials will have sought the best way to improve their intelligence, and may have long ago advanced beyond flesh-and-blood to artificial intelligence, constituting a postbiological universe. MacGowan and Ordway [Intelligence in the Universe, Prentice-Hall, Englewood Cliffs, NJ, 1966], Davies [Are We Alone? Philosophical Implications of the Discovery of Extraterrestrial Life, New York, Basic Books, 1995, pp. 51-55] and Shostak [Sharing the Universe: Perspectives on Extraterrestrial Life, Berkeley Hills, Berkeley, CA, 1998, pp. 103-109] have broached this subject, but it has not been given the attention it is due from its foundation in cultural evolution. Nor has the idea of a postbiological universe been carried to its logical conclusion, including a careful analysis of the implications for SETI. SETI scientists, social scientists, and experts in AI (such as Hans Moravec, who has spoken of a postbiological Earth in the next several generations) should consider the strengths and weaknesses of this new paradigm. (c) 2008 Published by Elsevier Ltd. C1 NASA Headquarters, Washington, DC 20546 USA. RP Dick, S (reprint author), NASA Headquarters, Washington, DC 20546 USA. EM Steven.j.Dick@nasa.gov NR 45 TC 6 Z9 6 U1 1 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0094-5765 J9 ACTA ASTRONAUT JI Acta Astronaut. PD APR-MAY PY 2008 VL 62 IS 8-9 BP 499 EP 504 DI 10.1016/j.actaastro.2008.01.025 PG 6 WC Engineering, Aerospace SC Engineering GA 294ZP UT WOS:000255445100005 ER PT J AU Palumbo, D AF Palumbo, Dan TI Deriving lifetime maps of coherent structures in the turbulent boundary layer SO AIAA JOURNAL LA English DT Article; Proceedings Paper CT AIAA/CEAS 12th Aeroacoustics Conference CY MAY 08-10, 2006 CL Cambridge, MA SP Amer Inst Aeronaut & Astronaut, CEAS ID WALL AB The lifetimes of coherent structures are derived from data correlated over a three-sensor array sampling streamwise sidewall pressure at high Reynolds number (>10(8)). The data were acquired at subsonic, transonic, and supersonic speeds aboard a Tupolev Tu-144. The lifetimes are computed from a variant of the correlation length termed the lifelength. Characteristic lifelengths are estimated by fitting a Gaussian distribution to the sensors' cross spectra and are shown to compare favorably with Efimtsov's prediction of correlation space scales. Lifelength distributions are computed in the time/frequency domain using an interval correlation technique on the continuous wavelet transform of the original time data. The median values of the lifelength distributions are found to be very close to the frequency-averaged result. The interval correlation technique is shown to allow the retrieval and inspection of the original time data of each event in the lifelength distributions, thus providing a means to locate and study the nature of the coherent structure in the turbulent boundary layer. The lifelength data are converted to lifetimes using the convection velocity. The lifetime of events in the time/frequency domain are displayed in lifetime maps. The primary purpose of the paper is to validate these new analysis techniques so that they can be used with confidence to further characterize the behavior of coherent structures in the turbulent boundary layer. C1 NASA, Langley Res Ctr, Struct Acoust Branch, Hampton, VA 23681 USA. RP Palumbo, D (reprint author), NASA, Langley Res Ctr, Struct Acoust Branch, Mail Stop 463, Hampton, VA 23681 USA. NR 14 TC 3 Z9 3 U1 0 U2 2 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0001-1452 J9 AIAA J JI AIAA J. PD APR PY 2008 VL 46 IS 4 BP 810 EP 823 DI 10.2514/1.30644 PG 14 WC Engineering, Aerospace SC Engineering GA 283TB UT WOS:000254658300002 ER PT J AU Helenbrook, BT Atkins, HL AF Helenbrook, Brian T. Atkins, H. L. TI Solving discontinuous Galerkin formulations of Poisson's equation using geometric and p multigrid SO AIAA JOURNAL LA English DT Article; Proceedings Paper CT AIAA 18th Computational Fluid Dynamics Conference CY JUN 25-28, 2007 CL Miami, FL SP Amer Inst Aeronaut & Astronaut ID FLOWS AB Methods for solving discontinuous Galerkin formulations of the Poisson equation by coupling p multigrid to geometric multigrid are investigated. The simple approach of performing iterative relaxation on solution approximations of decreasing polynomial degree p down to p = 0 and then applying geometric multigrid is ineffective. The transition from p = 1 top = 0 causes the performance of the entire iteration to degrade because the long wavelength eigenfunctions of the p = 1 discontinuous system are not represented well in the p = 0 space. A new approach is proposed that coarsens from the p = 1 discontinuous space to the p = 1 continuous space. This approach eliminates the problems caused by the p = 1 to p = 0 transition. Furthermore, the p = 1 continuous space is a standard finite element space for which geometric multigrid is well-defined. In addition, when the discontinuous Galerkin equations are restricted to a continuous space, one recovers the Galerkin formulation of continuous finite elements. Thus, applying geometric multigrid to this system is straightforward and effective. Numerical tests agree well with the analysis and confirm that the new approach gives rapid convergence rates that are grid-independent and only weakly sensitive to the polynomial order. C1 [Helenbrook, Brian T.] Clarkson Univ, Dept Mech & Aeronaut Engn, Potsdam, NY 13699 USA. [Atkins, H. L.] NASA, Langley Res Ctr, Computat Modeling & Simulat Branch, Hampton, VA 23681 USA. RP Helenbrook, BT (reprint author), Clarkson Univ, Dept Mech & Aeronaut Engn, Potsdam, NY 13699 USA. EM helenbrk@clarkson.edu; Harold.L.Atkins@nasa.gov NR 19 TC 5 Z9 5 U1 0 U2 1 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0001-1452 J9 AIAA J JI AIAA J. PD APR PY 2008 VL 46 IS 4 BP 894 EP 902 DI 10.2514/1.31163 PG 9 WC Engineering, Aerospace SC Engineering GA 283TB UT WOS:000254658300009 ER PT J AU Yang, HX Dembowski, RF Conrad, PG Downs, RT AF Yang, Hexiong Dembowski, Robert F. Conrad, Pamela G. Downs, Robert T. TI Crystal structure and Raman spectrum of hydroxyl-bastnasite-(Ce), CeCO3(OH) SO AMERICAN MINERALOGIST LA English DT Article DE bastnasite; hydroxyl-bastnasite-(Ce); single-crystal X-ray diffraction; crystal structure; Raman spectra ID RARE-EARTH; STRETCHING FREQUENCIES; PARISITE-(CE); SPECTROSCOPY; CARBONATES; BASTNASITE; (CE AB Hydroxyl-bstnasite-(Ce), ideally CeCO3(OH), had been regarded isostructurall with bdstnasite-(Ce), CeCO3F, the dominant member of the bastnasite family that produces -70% of the world's supply of rare-earth elements. Using single-crystal X-ray diffraction and Raman spectroscopy, our structural analysis on hydroxyl-bastnasite-(Ce) shows that the previous assumption is incorrect. The crystal structure of hydroxyl-bastnasite-(Ce) possesses P (6) over bar symmetry with unit-cell parameters a = 12.4112(2), c = 9.8511(3) angstrom, and V= 1314.2(1) angstrom(3), in contrast to the space group P (6) over bar 2c and a approximate to 7.10, c approximate to 9.76 angstrom, and V approximate to 430 angstrom(3) for bastnasite-(Ce). Moreover, there are 6, 3, and 5 symmetrically-distinct CO3 groups, Ce cations, and (OH/F) ions, respectively, in hydroxyl-bastnasite-(Ce), but 1, 1, and 2 in bastnasite-(Ce). The two structures, nevertheless, are similarly characterized by the layers Of CO3 groups alternating with the Ce-(OH/F) layers along the c direction. The Raman spectrum of hydroxyl-bastnasite-(Ce) is dominated by three strong bands at 1080, 1087, and 1098 cm(-1) in the CO3 symmetrical stretching region, along with at least four bands in the OH stretching region. Our study further suggests that natural hydroxyl-bastnasite-(Nd) is most likely isotypic with hydroxyl-bastnasite-(Ce), rather than with bastnasite-(Ce), as previously proposed. C1 [Yang, Hexiong; Dembowski, Robert F.; Downs, Robert T.] Univ Arizona, Dept Geosci, Tucson, AZ 85721 USA. [Conrad, Pamela G.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Yang, HX (reprint author), Univ Arizona, Dept Geosci, Tucson, AZ 85721 USA. EM hyang@u.arizona.edu NR 23 TC 5 Z9 5 U1 1 U2 21 PU MINERALOGICAL SOC AMER PI CHANTILLY PA 3635 CONCORDE PKWY STE 500, CHANTILLY, VA 20151-1125 USA SN 0003-004X J9 AM MINERAL JI Am. Miner. PD APR PY 2008 VL 93 IS 4 BP 698 EP 701 DI 10.2138/am.2008.2827 PG 4 WC Geochemistry & Geophysics; Mineralogy SC Geochemistry & Geophysics; Mineralogy GA 283SU UT WOS:000254657600024 ER PT J AU Tao, ZM McCormick, MP Wu, D Liu, ZY Vaughan, MA AF Tao, Zongming McCormick, M. Patrick Wu, Dong Liu, Zhaoyan Vaughan, Mark A. TI Measurements of cirrus cloud backscatter color ratio with a two-wavelength lidar SO APPLIED OPTICS LA English DT Article ID SPACEBORNE LIDAR; AEROSOL; CLIMATE AB We present observations of cirrus clouds from June 2006 to July 2007 performed by using a two-wavelength lidar located at Hampton University. For this time period, cirrus clouds were observed mostly in 7-13.5 km altitudes. Data analyses have been performed focusing on a color-ratio retrieval. In total, 86,369 samples from 1,689 profiles (1 min average and 15 m range resolution) containing cirrus clouds with attenuated backscatter ratio (ratio of attenuated total backscatter to the molecular backscatter) larger than 10 have been selected. The cirrus color ratio distribution shows a peak value at about 0.88 and a full width at half-maximum of 0.12. (C) 2008 Optical Society of America. C1 [Tao, Zongming; McCormick, M. Patrick; Wu, Dong] Hampton Univ, Ctr Atmospher Sci, Dept Atmospher & Planetary Sci, Hampton, VA 23668 USA. [Wu, Dong] Ocean Univ China, Minist Educ China, Key Lab Ocean Remote Sensing, Qingdao 266003, Peoples R China. [Liu, Zhaoyan] Natl Inst Aerosp, Hampton, VA 23666 USA. [Vaughan, Mark A.] NASA, Langley Res Ctr, SSAI, Hampton, VA 23681 USA. RP Liu, ZY (reprint author), Hampton Univ, Ctr Atmospher Sci, Dept Atmospher & Planetary Sci, Hampton, VA 23668 USA. EM Zhaoyan.Liu-1@nasa.gov RI Liu, Zhaoyan/A-9604-2009; Liu, Zhaoyan/B-1783-2010 OI Liu, Zhaoyan/0000-0003-4996-5738 NR 20 TC 28 Z9 33 U1 1 U2 6 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD APR 1 PY 2008 VL 47 IS 10 BP 1478 EP 1485 DI 10.1364/AO.47.001478 PG 8 WC Optics SC Optics GA 293OU UT WOS:000255345400034 PM 18382576 ER PT J AU Ottaviani, M Merck, C Long, S Koskulics, J Stamnes, K Su, W Wiscombe, W AF Ottaviani, M. Merck, C. Long, S. Koskulics, J. Stamnes, K. Su, W. Wiscombe, W. TI Time-resolved polarimetry over water waves: relating glints and surface statistics SO APPLIED OPTICS LA English DT Article ID EMPIRICAL MODE DECOMPOSITION; HILBERT SPECTRUM; OCEAN; ABSORPTION; VAPOR AB The phenomenon of sunglint, well known in satellite remote sensing, lacks a fundamental characterization under controlled laboratory conditions. Exploiting an apparatus specifically assembled for the purpose, we examine the signal collected by a photopolarimeter, pointed at a wavy water surface with measurable statistics and illuminated by a laser source. We also analyze the wave slope distributions, retrieved with an imaging system, and correlate them with the time series of glints. More particularly, we investigate the link between the occurrence of glints and that of the slopes from which they originate. In this context, the results obtained by applying the Hilbert-Huang transform technique to the slope time series are compared with those obtained through a traditional Fourier transform. This novel study first identifies the individual atomic glints as Fresnel reflection originating from a single wave facet. It then discusses the periodic character of a sequence of glints generated by a gravity wave state, as opposed to the erratic behavior of glints typical of capillary wave states. In mixed gravity-capillary conditions, it is shown that the glint properties are governed mainly by the capillary regime. (c) 2008 Optical Society of America. C1 [Ottaviani, M.; Merck, C.; Koskulics, J.; Stamnes, K.] Stevens Inst Technol, Dept Phys & Engn Phys, Hoboken, NJ 07030 USA. [Long, S.] NASA, Goddard Space Flight Ctr, WFF, Ocean Sci Branch, Wallops Isl, VA 23337 USA. [Su, W.] Sci Syst & Applicat Inc, Hampton, VA 23666 USA. [Wiscombe, W.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Ottaviani, M (reprint author), Stevens Inst Technol, Dept Phys & Engn Phys, Hoboken, NJ 07030 USA. EM mottavia@stevens.edu RI Wiscombe, Warren/D-4665-2012 OI Wiscombe, Warren/0000-0001-6844-9849 NR 24 TC 5 Z9 5 U1 1 U2 3 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD APR 1 PY 2008 VL 47 IS 10 BP 1638 EP 1648 DI 10.1364/AO.47.001638 PG 11 WC Optics SC Optics GA 293OU UT WOS:000255345400054 PM 18385775 ER PT J AU Bryce, D Kambhampati, S Smith, DE AF Bryce, Daniel Kambhampati, Subbarao Smith, David E. TI Sequential Monte Carlo in reachability heuristics for probabilistic planning SO ARTIFICIAL INTELLIGENCE LA English DT Article DE planning; heuristics ID SEARCH AB Some of the current best conformant probabilistic planners focus on finding a fixed length plan with maximal probability. While these approaches can find optimal solutions, they often do not scale for large problems or plan lengths. As has been shown in classical planning, heuristic search outperforms bounded length search (especially when an appropriate plan length is not given a priori). The problem with applying heuristic search in probabilistic planning is that effective heuristics are as yet lacking. In this work, we apply heuristic search to conformant probabilistic planning by adapting planning graph heuristics developed for non-deterministic planning. We evaluate a straight-forward application of these planning graph techniques, which amounts to exactly computing a distribution over many relaxed planning graphs (one planning graph for each joint outcome of uncertain actions at each time step). Computing this distribution is costly, so we apply Sequential Monte Carlo (SMC) to approximate it. One important issue that we explore in this work is how to automatically determine the number of samples required for effective heuristic computation. We empirically demonstrate on several domains how our efficient, but sometimes suboptimal, approach enables our planner to solve much larger problems than an existing optimal bounded length probabilistic planner and still find reasonable quality solutions. (c) 2007 Elsevier B.V All rights reserved. C1 [Bryce, Daniel] SRI Int, Ctr Artificial Intelligence, Menlo Pk, CA 94025 USA. [Kambhampati, Subbarao] Arizona State Univ, Dept Comp Sci & Engn, Tempe, AZ 85281 USA. [Smith, David E.] NASA, Ames Res Ctr, Intelligent Syst Div, Moffett Field, CA 94035 USA. RP Bryce, D (reprint author), SRI Int, Ctr Artificial Intelligence, 333 Ravenswood Ave, Menlo Pk, CA 94025 USA. EM bryce@ai.sri.com NR 49 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0004-3702 EI 1872-7921 J9 ARTIF INTELL JI Artif. Intell. PD APR PY 2008 VL 172 IS 6-7 BP 685 EP 715 DI 10.1016/j.artint.2007.10.018 PG 31 WC Computer Science, Artificial Intelligence SC Computer Science GA 268UI UT WOS:000253604800003 ER PT J AU Schulze-Makuch, D Turse, C Houtkooper, JM Mckay, CP AF Schulze-Makuch, Dirk Turse, Carol Houtkooper, Joop M. McKay, Christopher P. TI Testing the H2O2-H2O hypothesis for life on Mars with the TEGA instrument on the Phoenix lander SO ASTROBIOLOGY LA English DT Article DE hydrogen peroxide; Mars; life; biosignature; Phoenix water ID LACTIC-ACID BACTERIA; HYDROGEN-PEROXIDE; MARTIAN SOIL; OXYGEN; REACTIVITY; METABOLISM; STABILITY; CATALASE; MODEL AB In the time since the Viking life-detection experiments were conducted on Mars, many missions have enhanced our knowledge about the environmental conditions on the Red Planet. However, the martian surface chemistry and the Viking lander results remain puzzling. Non-biological explanations that favor a strong inorganic oxidant are currently favored ( e. g., Mancinelli, 1989; Plumb et al., 1989; Quinn and Zent, 1999; Klein, 1999; Yen et al., 2000), but problems remain regarding the lifetime, source, and abundance of that oxidant to account for the Viking observations ( Zent and McKay, 1994). Alternatively, a hypothesis that favors the biological origin of a strong oxidizer has recently been advanced (Houtkooper and Schulze-Makuch, 2007). Here, we report on laboratory experiments that simulate the experiments to be conducted by the Thermal and Evolved Gas Analyzer (TEGA) instrument of the Phoenix lander, which is to descend on Mars in May 2008. Our experiments provide a baseline for an unbiased test for chemical versus biological responses, which can be applied at the time the Phoenix lander transmits its first results from the martian surface. C1 [Schulze-Makuch, Dirk; Turse, Carol] Washington State Univ, Sch Earth & Environm Sci, Pullman, WA 99164 USA. [Houtkooper, Joop M.] Univ Giessen, Ctr Psychobiol & Behav Med, Giessen, Germany. [McKay, Christopher P.] NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. RP Schulze-Makuch, D (reprint author), Washington State Univ, Sch Earth & Environm Sci, Pullman, WA 99164 USA. EM dirksm@wsu.edu OI Schulze-Makuch, Dirk/0000-0002-1923-9746 NR 32 TC 4 Z9 5 U1 1 U2 11 PU MARY ANN LIEBERT INC PI NEW ROCHELLE PA 140 HUGUENOT STREET, 3RD FL, NEW ROCHELLE, NY 10801 USA SN 1531-1074 J9 ASTROBIOLOGY JI Astrobiology PD APR PY 2008 VL 8 IS 2 BP 205 EP 214 DI 10.1089/ast.2007.0216 PG 10 WC Astronomy & Astrophysics; Biology; Geosciences, Multidisciplinary SC Astronomy & Astrophysics; Life Sciences & Biomedicine - Other Topics; Geology GA 293QN UT WOS:000255349900001 PM 18393688 ER PT J AU Liu, DL Beegle, LW Kanik, I AF Liu, De-Ling Beegle, Luther W. Kanik, Isik TI Analysis of underivatized amino acids in geological samples using ion-pairing liquid chromatography and electrospray tandem mass spectrometry SO ASTROBIOLOGY LA English DT Article DE Mars; in situ life detection; organic molecules; amino acids ID CAPILLARY-ELECTROPHORESIS; MONO LAKE; MARS; IONIZATION; ENVIRONMENT; METABOLISM; CALIFORNIA; MERIDIANI; SOILS AB The capability of detecting biomarkers, such as amino acids, in chemically complex field samples is essential to establishing the knowledge required to search for chemical signatures of life in future planetary explorations. However, due to the complexities of in situ investigations, it is important to establish a new analytical scheme that utilizes a minimal amount of sample preparation. This paper reports the feasibility of a novel and sensitive technique, which has been established to quantitate amino acids in terrestrial crust samples directly without derivatization using volatile ion-pairing liquid chromatography and tandem mass spectrometry equipped with an electrospray ionization source. Adequate separation of 20 un-derivatized amino acids was achieved on a C-18 capillary column within 26 min with nonafluoropentanoic acid (NFPA) as ion-pairing reagent. Each amino acid was identified from its retention time as well as from its characteristic parent-to-daughter ion transition. Using tandem mass spectrometry as a detection technique allows co-elution of some amino acids, as it is more specific than traditional spectrophotometric methods. In the present study, terrestrial samples collected from 3 different locations were analyzed for their water-extractable free amino acid contents, following the removal of metal and organic interferences via ion exchange procedures. This is the first time that amino acids in geological samples were directly determined quantitatively without complicated derivatization steps. Depending on the amino acid, the detection limits varied from 0.02 to 5.7 pmol with the use of a 1 mu l sample injection loop. C1 [Liu, De-Ling; Beegle, Luther W.; Kanik, Isik] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Beegle, LW (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,MS 183-601, Pasadena, CA 91109 USA. EM Luther.Beegle@jpl.nasa.gov RI Beegle, Luther/A-6354-2010 NR 43 TC 13 Z9 13 U1 2 U2 12 PU MARY ANN LIEBERT INC PI NEW ROCHELLE PA 140 HUGUENOT STREET, 3RD FL, NEW ROCHELLE, NY 10801 USA SN 1531-1074 J9 ASTROBIOLOGY JI Astrobiology PD APR PY 2008 VL 8 IS 2 BP 229 EP 241 DI 10.1089/ast.2007.0176 PG 13 WC Astronomy & Astrophysics; Biology; Geosciences, Multidisciplinary SC Astronomy & Astrophysics; Life Sciences & Biomedicine - Other Topics; Geology GA 293QN UT WOS:000255349900003 PM 18393689 ER PT J AU Wang, R Wagg, J Carilli, CL Benford, DJ Dowell, CD Bertoldi, F Walter, F Menten, KM Omont, A Cox, P Strauss, MA Fan, XH Jiang, LH AF Wang, Ran Wagg, Jeff Carilli, Chris L. Benford, Dominic J. Dowell, C. Darren Bertoldi, Frank Walter, Fabian Menten, Karl M. Omont, Alain Cox, Pierre Strauss, Michael A. Fan, Xiaohui Jiang, Linhua TI Sharc-II 350 mu m observations of thermal emission from warm dust in z >= 5 quasars SO ASTRONOMICAL JOURNAL LA English DT Article DE galaxies : high-redshift; galaxies : starburst; infrared : galaxies; quasars : individual (SDSS J033829.31+002156.3, SDSS J075618.14+410408.6, SDSS J092721.82+200123.7, SDSS J104845.05+463718.3); submillimeter ID DIGITAL SKY SURVEY; HIGH-REDSHIFT QUASARS; ABSORPTION-LINE QUASAR; SURVEY COMMISSIONING DATA; BLACK-HOLE MASS; APM 08279+5255; ENERGY-DISTRIBUTIONS; MOLECULAR GAS; Z-GREATER-THAN-5.7 QUASARS; SUBMILLIMETER OBSERVATIONS AB We present observations of four z >= 5 SDSS quasars at 350 mu m with the SHARC-II bolometer camera on the Caltech Submillimeter Observatory. These are among the deepest observations that have been made by SHARC-II at 350 mu m, and three quasars are detected at >= 3 sigma significance, greatly increasing the sample of 350 mu m (corresponds to rest frame wavelengths of < 60 mu m at z >= 5), detected high-redshift quasars. The derived rest frame far-infrared (FIR) emission in the three detected sources is about five to ten times stronger than that expected from the average spectral energy distribution (SED) of the local quasars given the same 1450 angstrom luminosity. Combining the previous submillimeter and millimeter observations at longer wavelengths, the temperatures of the FIR-emitting warm dust from the three quasar detections are estimated to be in the range of 39-52 K. Additionally, the FIR-to-radio SEDs of the three 350 mu m detections are consistent with the emission from typical star-forming galaxies. The FIR luminosities are similar to 10(13)L(circle dot) and the dust masses are >= 10(8)M(circle dot). These results confirm that huge amounts of warm dust can exist in the host galaxies of optically bright quasars as early as z similar to 6. The universe is so young at these epochs (similar to 1Gyr) that a rapid dust-formation mechanism is required. We estimate the size of the FIR dust-emission region to be about a few kpc, and further provide a comparison of the SEDs among different kinds of dust-emitting sources to investigate the dominant dust-heating mechanism. C1 [Wang, Ran] Peking Univ, Dept Astron, Beijing 100871, Peoples R China. [Wang, Ran; Wagg, Jeff; Carilli, Chris L.] Natl Radio Astron Observ, Socorro, NM 87801 USA. [Benford, Dominic J.] NASA, Goddard Space Flight Ctr, Observat Cosmol Lab, Greenbelt, MD 20771 USA. [Dowell, C. Darren] Jet Prop Lab, Pasadena, CA 91109 USA. [Bertoldi, Frank] Univ Bonn, Argelander Inst Astron, D-53121 Bonn, Germany. [Walter, Fabian] Max Planck Inst Astron, D-69117 Heidelberg, Germany. [Menten, Karl M.] Max Planck Inst Radioastron, D-53121 Bonn, Germany. [Omont, Alain] Univ Paris 06, Paris, France. [Omont, Alain] CNRS, Inst Astrophys, Paris, France. [Cox, Pierre] Inst Radio Astron Millimetr, F-38406 St Martin Dheres, France. [Strauss, Michael A.] Princeton Univ, Dept Astrophys Sci, Princeton, NJ 08544 USA. [Fan, Xiaohui; Jiang, Linhua] Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. RP Wang, R (reprint author), Peking Univ, Dept Astron, Beijing 100871, Peoples R China. RI Benford, Dominic/D-4760-2012; Jiang, Linhua/H-5485-2016 OI Benford, Dominic/0000-0002-9884-4206; Jiang, Linhua/0000-0003-4176-6486 NR 58 TC 33 Z9 33 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0004-6256 J9 ASTRON J JI Astron. J. PD APR PY 2008 VL 135 IS 4 BP 1201 EP 1206 DI 10.1088/0004-6256/135/4/1201 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 283RX UT WOS:000254655300007 ER PT J AU Greene, TP Aspin, C Reipurth, B AF Greene, Thomas P. Aspin, Colin Reipurth, Bo TI High-resolution near-infrared spectroscopy of FUors and FUor-like stars SO ASTRONOMICAL JOURNAL LA English DT Article DE accretion; accretion disks; infrared : stars; stars : formation; stars : pre-main sequence; techniques : spectroscopic ID YOUNG STELLAR OBJECTS; FLAT-SPECTRUM PROTOSTARS; HERBIG-HARO OBJECTS; ORIONIS OBJECTS; ECHELLE SPECTROGRAPH; CLASS-I; EVOLUTION; L1551; PHOTOSPHERES; L1551-IRS-5 AB We present new high-resolution (R similar or equal to 18,000) near-infrared spectroscopic observations of a sample of classical FU Orionis stars (FUors) and other young stars with FUor characteristics that are sources of Herbig-Haro (HH) flows. Spectra are presented for the region lambda = 2.203-2.236 mu m which is rich in absorption lines sensitive to both effective temperatures and surface gravities of stars. Both FUors and FUor-like stars show numerous broad and weak-unidentified spectral features in this region. Spectra of the 2.280-2.300 mu m region are also presented, with the 2.2935 mu m v = 2-0 CO absorption bandhead being clearly the strongest feature seen in the spectra of all FUors and FUor-like stars. A cross-correlation analysis shows that FUor and FUor- like spectra in the 2.203-2.236 mu m region are not consistent with late-type dwarfs, giants, nor embedded protostars. The cross-correlations also show that the observed FUor- like HH energy sources have spectra that are substantively similar to those of FUors. Both object groups also have similar near-infrared colors. The large line widths and double-peaked nature of the spectra of the FUor- like stars are consistent with the established accretion disk model for FUors, also consistent with their near-infrared colors. It appears that young stars with FUor- like characteristics may be more common than projected from the relatively few known classical FUors. C1 [Greene, Thomas P.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. [Aspin, Colin; Reipurth, Bo] Univ Hawaii, Inst Astron, Hilo, HI 96720 USA. RP Greene, TP (reprint author), NASA, Ames Res Ctr, MS 245-6, Moffett Field, CA 94035 USA. EM thomas.p.greene@nasa.gov; caa@ifa.hawaii.edu; reipurth@ifa.hawaii.edu NR 52 TC 34 Z9 34 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0004-6256 J9 ASTRON J JI Astron. J. PD APR PY 2008 VL 135 IS 4 BP 1421 EP 1429 DI 10.1088/0004-6256/135/4/1421 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 283RX UT WOS:000254655300026 ER PT J AU Straughn, AN Meurer, GR Pirzkal, N Cohen, SH Malhotra, S Rhoads, J Windhorst, RA Gardner, JP Hathi, NP Xu, C Gronwall, C Koekemoer, AM Walsh, J Alighieri, SDS AF Straughn, Amber N. Meurer, Gerhardt R. Pirzkal, Norbert Cohen, Seth H. Malhotra, Sangeeta Rhoads, James Windhorst, Rogier A. Gardner, Jonathan P. Hathi, Nimish P. Xu, Chun Gronwall, Caryl Koekemoer, Anton M. Walsh, Jeremy Alighieri, Sperello Di Serego TI Emission-line galaxies from the pears Hubble ultra deep field: A 2D detection method and first results SO ASTRONOMICAL JOURNAL LA English DT Article DE galaxies : starburst; methods : data analysis; techniques : spectroscopic ID STAR-FORMATION RATE; INTERNATIONAL SPECTROSCOPIC SURVEY; LAMBDA-3727 LUMINOSITY FUNCTION; FRANCE REDSHIFT SURVEY; H-II REGIONS; FORMATION HISTORY; FORMATION-DENSITY; SPIRAL GALAXIES; LOCAL UNIVERSE; SURVEY LIST AB The Hubble Space Telescope Advanced Camera for Surveys grism Probing Evolution And Reionization Spectroscopically (PEARS) survey provides a large dataset of low-resolution spectra from thousands of galaxies in the GOODS north and south fields. One important subset of objects in these data is emission-line galaxies (ELGs), and we have investigated several different methods aimed at systematically selecting these galaxies. Here, we present a new methodology and results of a search for these ELGs in the PEARS observations of the Hubble Ultra Deep Field (HUDF) using a 2D detection method that utilizes the observation that many emission lines originate from clumpy knots within galaxies. This 2D line-finding method proves to be useful in detecting emission lines from compact knots within galaxies that might not otherwise be detected using more traditional 1D line-finding techniques. We find in total 96 emission lines in the HUDF, originating from 81 distinct "knots" within 63 individual galaxies. We find in general that [O III] emitters are the most common, comprising 44% of the sample, and on average have high equivalent widths (70% of [O III] emitters having rest-frame EW > 100 angstrom). There are 12 galaxies with multiple emitting knots-with different knots exhibiting varying flux values, suggesting that the differing star-formation properties across a single galaxy can in general be probed at redshifts less than or similar to 0.2-0.4. The most prevalent morphologies are large face-on spirals and clumpy interacting systems, many being unique detections owing to the 2D method described here, thus highlighting the strength of this technique. C1 [Straughn, Amber N.] Arizona State Univ, Dept Phys, Tempe, AZ 85287 USA. [Meurer, Gerhardt R.] Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. [Pirzkal, Norbert] Space Telescope Sci Inst, Baltimore, MD 21218 USA. [Cohen, Seth H.; Malhotra, Sangeeta; Rhoads, James; Windhorst, Rogier A.] Arizona State Univ, Sch Earth & Space Explorat, Tempe, AZ 85287 USA. [Gardner, Jonathan P.] Goddard Space Flight Ctr, Observat Cosmol Lab, Astrophys Sci Div, Greenbelt, MD 20771 USA. [Xu, Chun] Shanghai Inst Tech Phys, Shanghai 200083, Peoples R China. [Gronwall, Caryl] Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. [Walsh, Jeremy] ESO Space Telescope European Coordinating Facil, D-85748 Garching, Germany. [Alighieri, Sperello Di Serego] INAF Osservat Astrofis Arcetri, I-50125 Florence, Italy. RP Straughn, AN (reprint author), Arizona State Univ, Dept Phys, Tempe, AZ 85287 USA. EM amber.straughn@asu.edu RI di Serego Alighieri, Sperello/E-4067-2010; Hathi, Nimish/J-7092-2014; OI di Serego Alighieri, Sperello/0000-0001-8769-2692; Hathi, Nimish/0000-0001-6145-5090; Koekemoer, Anton/0000-0002-6610-2048 NR 50 TC 19 Z9 19 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0004-6256 J9 ASTRON J JI Astron. J. PD APR PY 2008 VL 135 IS 4 BP 1624 EP 1635 DI 10.1088/0004-6256/135/4/1624 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 283RX UT WOS:000254655300042 ER PT J AU Masetti, N Mason, E Morelli, L Cellone, SA McBride, VA Palazzi, E Bassani, L Bazzano, A Bird, AJ Charles, PA Dean, AJ Galaz, G Gehrels, N Landi, R Malizia, A Minniti, D Panessa, F Romero, GE Stephen, JB Ubertini, P Walter, R AF Masetti, N. Mason, E. Morelli, L. Cellone, S. A. McBride, V. A. Palazzi, E. Bassani, L. Bazzano, A. Bird, A. J. Charles, P. A. Dean, A. J. Galaz, G. Gehrels, N. Landi, R. Malizia, A. Minniti, D. Panessa, F. Romero, G. E. Stephen, J. B. Ubertini, P. Walter, R. TI Unveiling the nature of INTEGRAL objects through optical spectroscopy - VI. A multi-observatory identification campaign SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE galaxies : Seyfert; X-rays : binaries; stars : novae, cataclysmic variables; techniques : spectroscopic; X-rays : general ID ALL-SKY SURVEY; ACTIVE GALACTIC NUCLEI; X-RAY SOURCES; IBIS/ISGRI SURVEY SOURCES; BRIGHT SOURCE CATALOG; 6DF GALAXY SURVEY; FIND COUNTERPARTS; HOST GALAXIES; DATA RELEASE; SLEW SURVEY AB Using 8 telescopes in the northern and southern hemispheres, plus archival data from two on-line sky surveys, we performed a systematic optical spectroscopic study of 39 putative counterparts of unidentified or poorly studied INTEGRAL sources in order to determine or at least better assess their nature. This was implemented within the framework of our campaign to reveal the nature of newly-discovered and/or unidentified sources detected by INTEGRAL. Our results show that 29 of these objects are active galactic nuclei (13 of which are of Seyfert 1 type, 15 are Seyfert 2 galaxies and one is possibly a BL Lac object) with redshifts between 0.011 and 0.316, 7 are X-ray binaries (5 with high-mass companions and 2 with low-mass secondaries), one is a magnetic cataclysmic variable, one is a symbiotic star and one is possibly an active star. Thus, the large majority (74%) of the identifications in this sample belongs to the AGN class. When possible, the main physical parameters for these hard X-ray sources were also computed using the multiwavelength information available in the literature. These identifications further underscore the importance of INTEGRAL in studying the hard X-ray spectra of all classes of X-ray emitting objects, and the effectiveness of a strategy of multi-catalogue cross-correlation plus optical spectroscopy to securely pinpoint the actual nature of still unidentified hard X-ray sources. C1 [Masetti, N.; Palazzi, E.; Bassani, L.; Landi, R.; Malizia, A.; Stephen, J. B.] Ist Astrofis Spaziale & Fis Cosm Bologna, INAF, I-40129 Bologna, Italy. [Mason, E.] European So Observ, Santiago 19, Chile. [Morelli, L.] Univ Padua, Dipartimento Astron, I-35122 Padua, Italy. [Cellone, S. A.; Romero, G. E.] Univ Nacl La Plata, Fac Ciencias Astron & Geofis, La Plata, Buenos Aires, Argentina. [Cellone, S. A.] Consejo Nacl Invest Cient & Tecn, UNLP, IALP, RA-1033 Buenos Aires, DF, Argentina. [McBride, V. A.; Bird, A. J.; Charles, P. A.; Dean, A. J.] Univ Southampton, Sch Phys & Astron, Southampton SO17 1BJ, Hants, England. [Bazzano, A.; Panessa, F.; Ubertini, P.] Ist Astrofis Spaziale & Fis Cosm Bologna, INAF, I-00133 Rome, Italy. [Charles, P. A.] S African Astron Observ, ZA-7935 Cape Town, South Africa. [Galaz, G.; Minniti, D.] Pontificia Univ Catolica Chile, Dept Astron & Astrofis, Santiago 22, Chile. [Gehrels, N.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Romero, G. E.] Consejo Nacl Invest Cient & Tecn, Inst Argentino Radioastron, RA-1894 Buenos Aires, DF, Argentina. [Walter, R.] INTEGRAL Sci Data Ctr, CH-1290 Versoix, Switzerland. RP Masetti, N (reprint author), Ist Astrofis Spaziale & Fis Cosm Bologna, INAF, Via Gobetti 101, I-40129 Bologna, Italy. EM masetti@iasfbo.inaf.it RI Gehrels, Neil/D-2971-2012; Palazzi, Eliana/N-4746-2015; OI mason, elena/0000-0003-3877-0484; Malizia, Angela/0000-0002-6558-1163; Palazzi, Eliana/0000-0002-8691-7666; Bassani, Loredana/0000-0003-4858-6963; Masetti, Nicola/0000-0001-9487-7740; Bazzano, Angela/0000-0002-2017-4396; Panessa, Francesca/0000-0003-0543-3617 FU ASI; INAF [I/023/05/0]; US NSF [AST-90-15827]; ANPCyT [PICT 03-13291 BID 1728/OC-AR]; CONICET [PIP 5375]; FEDER funds [AYA2007-68034-C03-01]; University of Padua [CPDR061795/06] FX We thank Silvia Galleti for Service Mode observations at the Loiano telescope; Hripsime Navasardyan for Service Mode observations at the Asiago Telescope; Don Pollacco and Neil Mahoney for Service Mode observations at the WHT; Stefano Bernabei, Ivan Bruni, Antonio De Blasi and Roberto Gualandi for night assistance at the Loiano telescope; Claudio Aguilera, Arturo Gomez, Edgardo Cosgrove and Alberto Miranda for day and night assistance at the CTIO telescope; Antonio De Franceschi for night assistance at CASLEO; Gaspare Lo Curto and Alessandro Ederoclite for the support at the ESO telescopes; Ariel Sanchez and Andres Gonzalez for night assistance at the ESO 3.6 m telescope. We also thank the anonymous referee for useful remarks which helped us to improve the paper. This research has made use of the ASI Science Data Center Multimission Archive; it also used the NASA Astrophysics Data System Abstract Service, the NASA/ IPAC Extragalactic Database (NED), and the NASA/ IPAC Infrared Science Archive, which are operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. This publication made use of data products from the Two Micron All Sky Survey (2MASS), which is a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center/California Institute of Technology, funded by the National Aeronautics and Space Administration and the National Science Foundation. This research has also made use of data extracted from the 6dF Galaxy Survey and the Sloan Digitized Sky Survey archives; it has also made use of the ESO Science Archive operated at Garching bei Munchen, Germany, of the SIMBAD database operated at CDS, Strasbourg, France, and of the HyperLeda catalogue operated at the Observatoire de Lyon, France. The authors acknowledge the ASI and INAF financial support via grant No. I/023/05/0. N. M. and S. A. C. were Visiting Astronomers at CASLEO, operated under agreement between the Consejo Nacional de Investigaciones Cientificas y Tecnicas de la Republica Argentina and the National Universities of La Plata, Cordoba and San Juan. The CCD and data acquisition system at CASLEO have been partly financed by R. M. Rich through US NSF grant AST-90-15827. G. E. R. and S. A. C. were supported by grants PICT 03-13291 BID 1728/OC-AR (ANPCyT), PIP 5375 (CONICET), and AYA2007-68034-C03-01 (FEDER funds). L. M. is supported by the University of Padua through grant No. CPDR061795/06. N. M. thanks ESO for the pleasant hospitality in Santiago de Chile during the preparation of this paper. NR 92 TC 66 Z9 66 U1 0 U2 2 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD APR PY 2008 VL 482 IS 1 BP 113 EP 132 DI 10.1051/0004-6361:20079332 PG 20 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 346BA UT WOS:000259042200010 ER PT J AU de Martino, D Matt, G Mukai, K Bonnet-Bidaud, JM Falanga, M Gansicke, BT Haberl, F Marsh, TR Mouchet, M Littlefair, SP Dhillon, V AF de Martino, D. Matt, G. Mukai, K. Bonnet-Bidaud, J. -M. Falanga, M. Gansicke, B. T. Haberl, F. Marsh, T. R. Mouchet, M. Littlefair, S. P. Dhillon, V. TI 1RXS J173021.5-055933: a cataclysmic variable with a fast-spinning magnetic white dwarf SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE stars : binaries : close; stars : individual : 1RXS J173021.5; 055933; stars : novae; cataclysmic variables; white dwarfs ID X-RAY-EMISSION; PERIOD INTERMEDIATE POLAR; PHOTON IMAGING CAMERA; DIGITAL-SKY-SURVEY; XMM-NEWTON; OPTICAL SPECTROSCOPY; AE AQUARII; BEPPOSAX OBSERVATIONS; INTEGRAL OBJECTS; URSAE MAJORIS AB Aims. We present the first X-ray observations with the XMM-Newton and INTEGRAL satellites of the recently discovered cataclysmic variable 1RXS J173021.5-055933, together with simultaneous UV and coordinated optical photometry aiming at characterising its broad-band temporal and spectral properties and classifying this system as a magnetic one. Methods. We performed a timing analysis of the X-ray, UV, and optical light curves to identify and to study the energy dependence of the fast 128 s pulsation over a wide energy range. X-ray spectral analysis in the broad 0.2-100 keV X-ray range was performed to characterise the peculiar emission properties of this source. Results. We find that the X-ray light curve is dominated by the spin period of the accreting white dwarf in contrast to the far-UV range, which turns out to be unmodulated at a 3 sigma level. Near-UV and optical pulses are instead detected at twice the spin frequency. We identify the contributions from two accreting poles that imply a moderately inclined dipole field allowing, one pole to dominate at energies at least up to 10 keV, and a secondary that instead is negligible above 5 keV. X-ray spectral analysis reveals the presence of multiple emission components consisting of optically thin plasma with temperatures ranging from 0.17 keV to 60 keV and a hot blackbody at similar to 90 eV. The spectrum is also strongly affected by peculiar absorption components consisting of two high-density (similar to 3 x 10(21) cm(-2) and 2 x 10(23) cm(-2)) intervening columns, plus a warm absorber. The last is detected from an OVII absorption edge at 0.74 keV, which suggests that photoionization of pre-shock material is also occurring in this system. Conclusions. The observed properties indicate that the accretor in 1RXS J173021.5-055933 is a white dwarf with a likely weak magnetic field, thus confirming this cataclysmic variable as an intermediate polar (IP) with one of the most extreme spin-to-orbit period ratios. This system also joins the small group of IPs showing a soft X-ray reprocessed component, suggesting that this characteristics is not uncommon in these systems. C1 [de Martino, D.] Osserv Astron Capodimonte, INAF, I-80131 Naples, Italy. [Matt, G.] Univ Roma Tre, Dept Fis, I-00146 Rome, Italy. [Mukai, K.] Univ Maryland, Dept Phys, Baltimore, MD 21250 USA. [Mukai, K.] NASA, Goddard Space Flight Ctr, Xray Astrophys Lab, Greenbelt, MD 20771 USA. [Mukai, K.] NASA, Goddard Space Flight Ctr, CRESST, Greenbelt, MD 20771 USA. [Bonnet-Bidaud, J. -M.; Falanga, M.] CE Saclay, DSM DAPNIA SAp, Serv Astrophys, F-91191 Gif Sur Yvette, France. [Gansicke, B. T.; Marsh, T. R.] Univ Warwick, Dept Phys, Coventry CV4 7AL, W Midlands, England. [Haberl, F.] Max Planck Inst Extraterr Phys, D-85741 Garching, Germany. [Mouchet, M.] Observ Paris, LUTH, F-92190 Meudon, France. [Mouchet, M.] Univ Paris 07, Lab APC, F-75013 Paris, France. [Littlefair, S. P.; Dhillon, V.] Univ Sheffield, Dept Phys & Astron, Sheffield S3 7RH, S Yorkshire, England. RP de Martino, D (reprint author), Osserv Astron Capodimonte, INAF, Via Moiariello 16, I-80131 Naples, Italy. EM demartino@na.astro.it; matt@fis.uniroma3.it; mukai@milkyway.gsfc.nasa.gov; bonnetbidaud@cea.fr; mfalanga@cea.fr; boris.gaensicke@warwick.ac.uk; fwh@mpe.mpg.de; Tom.Marsh@warwick.ac.uk; martine.mouchet@obspm.fr; s.littlefair@shef.ac.uk; vik.dhillon@shef.ac.uk RI Gaensicke, Boris/A-9421-2012; OI Gaensicke, Boris/0000-0002-2761-3005; Haberl, Frank/0000-0002-0107-5237; Littlefair, Stuart/0000-0001-7221-855X; de Martino, Domitilla/0000-0002-5069-4202 NR 77 TC 20 Z9 20 U1 0 U2 1 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 1432-0746 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD APR PY 2008 VL 481 IS 1 BP 149 EP 159 DI 10.1051/0004-6361:20078368 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 277EJ UT WOS:000254195200031 ER PT J AU Pottasch, SR Bernard-Salas, J Roellig, TL AF Pottasch, S. R. Bernard-Salas, J. Roellig, T. L. TI Abundances of planetary nebula NGC2392 SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE ISM : planetary nebulae : individual : NGC2392; infrared : ISM ID SPITZER-SPACE-TELESCOPE; CENTRAL STARS; INFRARED SPECTROGRAPH; 4.85 GHZ; CATALOG; EVOLUTION; RADIATION; EMISSION; NGC-2392; NUCLEI AB The spectra of the planetary nebula NGC2392 is reanalysed using spectral measurements made in the mid-infrared with the Spitzer Space Telescope. The aim is to determine the chemical composition of this object. We also make use of IUE and ground based spectra. Abundances determined from the mid-infrared lines, which are insensitive to electron temperature, are used as the basis for the determination of the composition, which are found to differ somewhat from earlier results. The abundances found, especially the low value of helium and oxygen, indicate that the central star was originally of rather low mass. Abundances of phosphorus, iron, silicon and chlorine have been determined for the first time in this nebula. The variation of electron temperature in this nebula is very clear, reaching quite high values close to the center. The temperature of the central star is discussed in the light of the observed high stages of ionization. The nebular information indicates that the spectrum of the star deviates considerably from a blackbody. C1 [Pottasch, S. R.] Univ Groningen, Kapteyn Astron Inst, NL-9700 AV Groningen, Netherlands. [Bernard-Salas, J.] Cornell Univ, Ctr Radiophys & Space Res, Ithaca, NY 14853 USA. [Roellig, T. L.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Pottasch, SR (reprint author), Univ Groningen, Kapteyn Astron Inst, POB 800, NL-9700 AV Groningen, Netherlands. EM pottasch@astro.rug.nl NR 40 TC 18 Z9 18 U1 0 U2 1 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD APR PY 2008 VL 481 IS 2 BP 393 EP 400 DI 10.1051/0004-6361:20079041 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 281RH UT WOS:000254515800014 ER PT J AU Witthoeft, MC Badnell, NR AF Witthoeft, M. C. Badnell, N. R. TI Atomic data from the IRON project - LXV. Electron-impact excitation of Fe6+ SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE atomic data ID FORBIDDEN EMISSION-LINES; CA-LIKE IRON; OSCILLATOR-STRENGTHS; IONS; VII; N=4 AB We present R-matrix results for the electron-impact excitation of Fe6+. The intermediate-coupling frame transformation (ICFT) method has been used to obtain level-resolved collision strengths. We then calculate effective collision strengths assuming a Maxwellian distribution for the incident electron velocities. A large configuration interaction (CI) expansion of 1896 LS terms (4776 fine-structure levels) is used to obtain an accurate target. This is reduced to 89 close-coupling (CC) terms (189 levels) for the scattering calculation. To investigate the importance of CI, we also perform a second calculation with the same CC expansion but a smaller CI expansion. We discuss the difficulties of such a comparison and look at which transitions show the most sensitivity to the CI expansion. Our effective collision strengths are compared with a previous IRON Project report (Berrington et al. 2000, A&A, 142, 313) for transitions within the ground configuration and a recent distorted wave calculation (Zeng et al. 2005, MNRAS, 357, 440) for transitions to excited configurations. We find good agreement with the results of the previous R-matrix calculation and with the high-temperature distorted-wave results for most transitions, although there are some significant differences at lower temperatures in the latter case. C1 [Witthoeft, M. C.; Badnell, N. R.] Univ Strathclyde, Dept Phys, Glasgow G4 0NG, Lanark, Scotland. [Witthoeft, M. C.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Witthoeft, MC (reprint author), Univ Strathclyde, Dept Phys, Glasgow G4 0NG, Lanark, Scotland. EM witthoef@milkyway.gsfc.nasa.gov NR 17 TC 21 Z9 21 U1 0 U2 4 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD APR PY 2008 VL 481 IS 2 BP 543 EP 551 DI 10.1051/0004-6361:20079073 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 281RH UT WOS:000254515800030 ER PT J AU Searle, SC Prinja, RK Massa, D Ryans, R AF Searle, S. C. Prinja, R. K. Massa, D. Ryans, R. TI Quantitative studies of the optical and UV spectra of Galactic early B supergiants - I. Fundamental parameters SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE techniques : spectroscopic; stars : mass-loss; stars : supergiants; stars : abundances; stars : atmospheres; stars : fundamental parameters ID O-TYPE STARS; BLANKETED MODEL ATMOSPHERES; EFFECTIVE TEMPERATURE SCALE; LOW METALLICITY ENVIRONMENT; SMALL-MAGELLANIC-CLOUD; DRIVEN STELLAR WINDS; MASS-LOSS RATES; CHEMICAL-COMPOSITIONS; PHYSICAL-PROPERTIES; EVOLUTIONARY STATUS AB Aims. We undertake an optical and ultraviolet spectroscopic analysis of a sample of 20 Galactic B0-B5 supergiants of luminosity classes Ia, Ib, Iab, and II. Fundamental stellar parameters are obtained from optical diagnostics and a critical comparison of the model predictions to observed UV spectral features is made. Methods. Fundamental parameters (e.g., T(eff), logL(*), mass-loss rates and CNO abundances) are derived for individual stars using CMFGEN, a nLTE, line-blanketed model atmosphere code. The impact of these newly derived parameters on the Galactic B super-giant T(eff) scale, mass discrepancy, and wind-momentum luminosity relation is examined. Results. The B supergiant temperature scale derived here shows a reduction of about 1000-3000 K compared to previous results using unblanketed codes. Mass-loss rate estimates are in good agreement with predicted theoretical values, and all of the 20 B0-B5 supergiants analysed show evidence of CNO processing. A mass discrepancy still exists between spectroscopic and evolutionary masses, with the largest discrepancy occurring at log (L/L(circle dot)) similar to 5.4. The observed WLR values calculated for B0-B0.7 supergiants are higher than predicted values, whereas the reverse is true for B1-B5 supergiants. This means that the discrepancy between observed and theoretical values cannot be resolved by adopting clumped (i.e., lower) mass-loss rates as for O stars. The most surprising result is that, although CMFGEN succeeds in reproducing the optical stellar spectrum accurately, it fails to precisely reproduce key UV diagnostics, such as the Nv and C IV P Cygni profiles. This problem arises because the models are not ionised enough and fail to reproduce the full extent of the observed absorption trough of the P Cygni profiles. Conclusions. Newly-derived fundamental parameters for early B supergiants are in good agreement with similar work in the field. The most significant discovery, however, is the failure of CMFGEN to predict the correct ionisation fraction for some ions. Such findings add further support to revising the current standard model of massive star winds, as our understanding of these winds is incomplete without a precise knowledge of the ionisation structure and distribution of clumping in the wind. C1 [Searle, S. C.; Prinja, R. K.] UCL, Dept Phys & Astron, London WC1E 6BT, England. [Massa, D.] NASA, Goddard Space Flight Ctr, SGT Inc, Greenbelt, MD 20771 USA. [Ryans, R.] Queens Univ Belfast, Dept Phys & Astron, Belfast BT7 1NN, Antrim, North Ireland. RP Searle, SC (reprint author), UCL, Dept Phys & Astron, Gower St, London WC1E 6BT, England. EM scs@star.ucl.ac.uk; rkp@star.ucl.ac.uk; massa@taotaomona.gsfc.nasa.gov; r.ryans@qub.ac.uk NR 70 TC 64 Z9 65 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD APR PY 2008 VL 481 IS 3 BP 777 EP U65 DI 10.1051/0004-6361:20077125 PG 33 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 285CF UT WOS:000254754200024 ER PT J AU Brunetto, R Roush, TL AF Brunetto, R. Roush, T. L. TI Impact of irradiated methane ice crusts on compositional interpretations of TNOs SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE astrochemistry; Kuiper Belt; Oort Cloud; solar system : general; methods : laboratory ID EDGEWORTH-KUIPER-BELT; OPTICAL-CONSTANTS; ION IRRADIATION; LABORATORY EXPERIMENTS; FROZEN METHANOL; INFRARED SPECTROSCOPY; MU-M; OBJECTS; REFLECTANCE; MICROWAVE AB Context. Minor bodies in the outer solar system show a wide variety of spectral colors related to both composition and surface processing, e. g. cosmic ion irradiation. Aims. We investigate the effect of an irradiation mantle on the reflectance spectrum in the V-NIR (visible-near-infrared) range. In particular we investigate the condition needed for a weathering crust to mask the presence of water ice. Methods. We start from laboratory experiments of ion irradiated methane ice to study the optical properties of the hydrocarbon residue by-product of the space weathering process. We compare the real and imaginary index of refraction with those of Titan and ice tholins and with those of amorphous carbon. We use the estimated optical constants to model a layered configuration using the Hapke theory, varying the thickness and grain size of the modeled crust. Results. We find that a relatively thin (tens of microns) crust of irradiated methane by-products can mask the presence of water ice bands in the spectrum, while a much larger layer of tholins would be required to produce a similar effect. We also estimate the conditions for the detection of water ice on trans-Neptunian objects (TNOs). We discuss the results in view of the astrophysical timescale. C1 [Brunetto, R.] Univ Salento, Dipartimento Fis, I-73100 Lecce, Italy. [Brunetto, R.] INAF Osservatorio Astrofis Catania, I-95123 Catania, Italy. [Roush, T. L.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Brunetto, R (reprint author), Univ Paris 11, UMR 8617, Inst Astrophys Spatiale, Batiment 121, F-91405 Orsay, France. EM rosario.brunetto@ias.u-psud.fr NR 31 TC 25 Z9 25 U1 1 U2 2 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD APR PY 2008 VL 481 IS 3 BP 879 EP 882 DI 10.1051/0004-6361:20078889 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 285CF UT WOS:000254754200034 ER PT J AU Gezari, S Basa, S Martin, DC Bazin, G Forster, K Milliard, B Halpern, JP Friedman, PG Morrissey, P Neff, SG Schiminovich, D Seibert, M Small, T Wyder, TK AF Gezari, S. Basa, S. Martin, D. C. Bazin, G. Forster, K. Milliard, B. Halpern, J. P. Friedman, P. G. Morrissey, P. Neff, S. G. Schiminovich, D. Seibert, M. Small, T. Wyder, T. K. TI UV/optical detections of candidate tidal disruption events by GALEX and CFHTLS SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : g nuclei; ultraviolet : galaxies; X-rays : galaxies ID ACTIVE GALACTIC NUCLEI; DIGITAL SKY SURVEY; MASSIVE BLACK-HOLE; SUPERNOVA LEGACY SURVEY; GALAXY-EVOLUTION-EXPLORER; HUBBLE-SPACE-TELESCOPE; X-RAY OBSERVATIONS; NEARBY GALAXIES; SIGMA RELATION; GROTH STRIP AB We present two luminous UV/optical flares from the nuclei of apparently inactive early-type galaxies at z = 0.37 and 0.33 that have the radiative properties of a flare from the tidal disruption of a star. In this paper we report the second candidate tidal disruption event discovery in the UV by the GALEX Deep Imaging Survey and present simultaneous optical light curves from the CFHTLS Deep Imaging Survey for both UV flares. The first few months of the UV/optical light curves are well fitted with the canonical t(-5/3) power-law decay predicted for emission from the fallback of debris from a tidally disrupted star. Chandra ACIS X-ray observations during the flares detect soft X-ray sources with T(bb) = (2-5) x 10(5) K or Gamma > 3 and place limits on hard X-ray emission from an underlying AGN down to L(X)(2-10 keV) less than or similar to 10(41) ergs s(-1). Blackbody fits to the UV/optical spectral energy distributions of the flares indicate peak flare luminosities of greater than or similar to 10(44) - 10(45) ergs s(-1). The temperature, luminosity, and light curves of both flares are in excellent agreement with emission from a tidally disrupted main-sequence star onto a central black hole of several times 10(7) M(circle dot). The observed detection rate of our search over similar to 2.9 deg(2) of GALEX Deep Imaging Survey data spanning from 2003 to 2007 is consistent with tidal disruption rates calculated from dynamical models, and we use these models to make predictions for the detection rates of the next generation of optical synoptic surveys. C1 [Gezari, S.; Martin, D. C.; Forster, K.; Friedman, P. G.; Morrissey, P.; Small, T.; Wyder, T. K.] CALTECH, Pasadena, CA 91125 USA. [Gezari, S.; Basa, S.; Milliard, B.] Lab Astrophys Marseille, F-13376 Marseille 12, France. [Bazin, G.] CEA Saclay, DSM, DAPNIA, F-91191 Gif Sur Yvette, France. [Halpern, J. P.; Schiminovich, D.] Columbia Univ, Dept Astron, New York, NY 10027 USA. [Neff, S. G.] NASA, Goddard Space Flight Ctr, Astron & Solar Phys Lab, Greenbelt, MD 20771 USA. [Seibert, M.] Observ Carnegie Inst Washington, Los Angeles, CA 90095 USA. RP Gezari, S (reprint author), CALTECH, Pasadena, CA 91125 USA. EM suvi@srl.caltech.edu NR 99 TC 121 Z9 121 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 1 PY 2008 VL 676 IS 2 BP 944 EP 969 DI 10.1086/529008 PG 26 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 281WW UT WOS:000254530600014 ER EF