FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Ho, CH Kim, JH Lau, KM Kim, KM Gong, DY Lee, YB AF Ho, CH Kim, JH Lau, KM Kim, KM Gong, DY Lee, YB TI Interdecadal changes in heavy rainfall in China during the northern summer SO TERRESTRIAL ATMOSPHERIC AND OCEANIC SCIENCES LA English DT Article DE interdecadal changes; heavy rainfall; East Asian summer monsoon; China; large-scale circulation ID CLIMATE; MONSOON; EAST; PRECIPITATION; TEMPERATURE; VARIABILITY AB Using ground observations of daily rainfall over China during summer (June - August) for the period 1961 - 95, we examined interdecadal changes in the distribution of rainy events as a function of the rain rate and assessed their contributions to the total summer rainfall. We found that central China was wetter, and northern and southern China were drier in the decades following 1979 as compared to the earlier decades. The interdecadal changes in the Chinese summer rainfall are closely linked to those in large-scale circulations: the southward displacement off a westerly wind at the levels of 200 and 850 hPa over East Asia and an enhanced 850 hPa northerly wind over central-eastern China. The corresponding 850 hPa relative vorticity increased (decreased) over central (northern and southern) China where the summer rainfall has increased (decreased) during the later decades. Interestingly, the change in the total number of rainy events was found to be negligible during the entire period of data collection. Across the overall region (mostly eastern China), a large amount of interdecadal changes is accounted for by less than 20% of the total number of rainy events in the heavy-to-extremely-heavy categories (>=similar to 25 mm day(-1)). The possible causes-associated with large-scale circulations-and the implications of the present results are discussed. C1 Seoul Natl Univ, Sch Earth & Environm Sci, Seoul, South Korea. NASA, Goddard Space Flight Ctr, Lab Atmosphere, Greenbelt, MD 20771 USA. Sci Syst & Applicat Inc, Lanham, MD USA. Beijing Normal Univ, Inst Resource Sci, Key Lab Environm Change & Nat Disaster, Beijing 100875, Peoples R China. RP Ho, CH (reprint author), Seoul Natl Univ, Sch Earth & Environm Sci, Seoul, South Korea. EM hoch@cpl.snu.ac.kr RI Kim, Joo-Hong/J-8929-2012; Kim, Kyu-Myong/G-5398-2014; Ho, Chang-Hoi/H-8354-2015; Lau, William /E-1510-2012 OI Kim, Joo-Hong/0000-0003-3087-9864; Lau, William /0000-0002-3587-3691 NR 20 TC 17 Z9 18 U1 0 U2 2 PU CHINESE GEOSCIENCE UNION PI TAIPEI PA PO BOX 23-59, TAIPEI 10764, TAIWAN SN 1017-0839 J9 TERR ATMOS OCEAN SCI JI Terr. Atmos. Ocean. Sci. PD DEC PY 2005 VL 16 IS 5 BP 1163 EP 1176 PG 14 WC Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences; Oceanography SC Geology; Meteorology & Atmospheric Sciences; Oceanography GA 019ZU UT WOS:000235878300011 ER PT J AU DellaCorte, C AF DellaCorte, C TI Lower gas prices bring early holiday gift SO TRIBOLOGY & LUBRICATION TECHNOLOGY LA English DT Editorial Material C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP DellaCorte, C (reprint author), NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. EM cdellacorte@stle.org NR 0 TC 0 Z9 0 U1 0 U2 1 PU SOC TRIBOLOGISTS & LUBRICATION ENGINEERS PI PARK RIDGE PA 840 BUSSE HIGHWAY, PARK RIDGE, IL 60068 USA SN 0024-7154 J9 TRIBOL LUBR TECHNOL JI Tribol. Lubr. Technol. PD DEC PY 2005 VL 61 IS 12 BP 6 EP 6 PG 1 WC Engineering, Mechanical SC Engineering GA 993NN UT WOS:000233960900002 ER PT J AU Grotzinger, JP Arvidson, RE Bell, JF Calvin, W Clark, BC Fike, DA Golombek, M Greeley, R Haldemann, A Herkenhoff, KE Jolliff, BL Knoll, AH Malin, M McLennan, SM Parker, T Soderblom, L Sohl-Dickstein, JN Squyres, SW Tosca, NJ Watters, WA AF Grotzinger, JP Arvidson, RE Bell, JF Calvin, W Clark, BC Fike, DA Golombek, M Greeley, R Haldemann, A Herkenhoff, KE Jolliff, BL Knoll, AH Malin, M McLennan, SM Parker, T Soderblom, L Sohl-Dickstein, JN Squyres, SW Tosca, NJ Watters, WA TI Stratigraphy and sedimentology of a dry to wet eolian depositional system, Burns formation, Meridiani Planum, Mars SO EARTH AND PLANETARY SCIENCE LETTERS LA English DT Article DE Mars; Meridiani; sedimentology; environmental history; stratigraphy; eolian ID UNIDIRECTIONAL WATER FLOWS; AEOLIAN DUNE SANDS; WHITE-SANDS; BED CONFIGURATIONS; NEW-MEXICO; SEQUENCE STRATIGRAPHY; INTERDUNE DEPOSITS; OPPORTUNITY ROVER; BOUNDING SURFACES; LANDING SITE AB Outcrop exposures of sedimentary rocks at the Opportunity landing site (Meridiani Planum) form a set of genetically related strata defined here informally as the Burns formation. This formation call be subdivided into lower, middle, and upper units which, respectively, represent eolian dune, eolian sand sheer, and mixed eolian sand sheet and interdune facies associations. Collectively, these three units are at least 7 m thick and define a "wetting-upward" Succession which records a progressive increase in the influence of groundwater and, ultimately, surface water in controlling primary depositional processes. The Burns lower unit is interpreted as a dry dune field (though grain composition indicates an evaporitic source), whose preserved record of large-scale cross-bedded sandstones indicates either superimposed bedforms of variable size or reactivation of lee-side slip faces by episodic (possibly seasonal) changes in wind direction. The boundary between the lower and middle units is a significant eolian deflation surface. This surface is interpreted to record eolian erosion down to the capillary fringe of the water table, where increased resistance to wind-induced erosion was promoted by increased sediment cohesiveness in the capillary fringe. The overlying Burns middle unit is characterized by fine-scale planar-laminated to low-angle-stratified sandstones. These sandstones accumulated during lateral migration of eolian impact ripples over the flat to gently undulating sand sheet surface. In terrestrial settings, sand sheets may form ail intermediate environment between dune fields and interdune or playa surfaces. The contact between the middle and upper units of the Burns formation is interpreted as a diagenetic front, where recrystallization in the phreatic or capillary zones may have occurred, The upper unit of the Burns formation contains a mixture of sand sheet facies and interdune facies. Interdune facies include wavy bedding, irregular lamination with convolute bedding and possible small tepee or salt-ridge structures, and cm-scale festoon cross-lamination indicative of shallow subaqueous flows marked by current velocities of a few tens of cm/s. Most likely, these currents were gravity-driven, possibly unchannelized flows resulting from the flooding of interdune/playa surfaces. However, evidence for lacustrine sedimentation, including mudstones or in situ bottom-growth evaporites, has not been observed so far at Eagle and Endurance craters. Mineralogical and elemental data indicate that the eolian sandstones of the lower and middle units, as well as the subaqueous and eolian deposits of the Burns upper unit, were derived from an evaporitic source. This indirectly points to a temporally equivalent playa where lacustrine evaporites or ground-water-generated efflorescent crusts were deflated to provide a source of sand-sized particles that were entrained to form eolian dunes and sand sheets. This process is responsible for the development of sulfate eolianites at White Sands, New Mexico, and could have provided a prolific flux of sulfate sediment at Meridiani. Though evidence for surface water in the Burns formation is mostly limited to the upper unit, the associated sulfate eolianites provide strong evidence for the critical role of groundwater in controlling sediment production and stratigraphic architecture throughout the formation. (c) 2005 Elsevier B.V. All rights reserved. C1 CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA. MIT, Cambridge, MA 02139 USA. Washington Univ, Dept Earth & Planetary Sci, St Louis, MO 63130 USA. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. Univ Nevada, Reno, NV 89501 USA. Lockheed Martin Corp, Littleton, CO 80127 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Arizona State Univ, Dept Geol Sci, Tempe, AZ 85287 USA. US Geol Survey, Flagstaff, AZ 86001 USA. Harvard Univ, Bot Museum, Cambridge, MA 02138 USA. Malin Space Sci Syst Inc, San Diego, CA 92191 USA. SUNY Stony Brook, Dept Geosci, Stony Brook, NY 11794 USA. RP Grotzinger, JP (reprint author), CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA. EM grotz@gps.caltech.edu RI Fike, David/D-3634-2011 OI Fike, David/0000-0003-2848-0328 NR 98 TC 269 Z9 273 U1 14 U2 76 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 NOV 30 PY 2005 VL 240 IS 1 BP 11 EP 72 DI 10.1016/j.epsl.2005.09.039 PG 62 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 990BJ UT WOS:000233717900002 ER PT J AU Clark, BC Morris, RV McLennan, SM Gellert, R Jolliff, B Knoll, AH Squyres, SW Lowenstein, TK Ming, DW Tosca, NJ Yen, A Christensen, PR Gorevan, S Bruckner, J Calvin, W Dreibus, G Farrand, W Klingelhoefer, G Waenke, H Zipfel, J Bell, JF Grotzinger, J McSween, HY Rieder, R AF Clark, BC Morris, RV McLennan, SM Gellert, R Jolliff, B Knoll, AH Squyres, SW Lowenstein, TK Ming, DW Tosca, NJ Yen, A Christensen, PR Gorevan, S Bruckner, J Calvin, W Dreibus, G Farrand, W Klingelhoefer, G Waenke, H Zipfel, J Bell, JF Grotzinger, J McSween, HY Rieder, R TI Chemistry and mineralogy of outcrops at Meridiani Planum SO EARTH AND PLANETARY SCIENCE LETTERS LA English DT Article DE Mars; outcrop; Meridiani; chemical sediment; sulfate; kieserite; jarosite; rover; MER; opportunity ID X-RAY SPECTROMETER; GUSEV CRATER; CHEMICAL-COMPOSITION; SPIRIT ROVER; MARTIAN SOIL; MOSSBAUER SPECTROMETER; BURNS FORMATION; EARLY MARS; ROCKS; WATER AB Analyses of outcrops created by the impact craters Endurance, Fram and Eagle reveal the broad lateral continuity of chemical sediments at the Meridiani Planum exploration site on Mars. Approximately ten mineralogical components are implied in these salt-rich silicic sediments, from measurements by instruments on the Opportunity rover. Compositional trends in an apparently intact vertical stratigraphic sequence at the Karatepe West ingress point at Endurance crater are consistent with non-uniform deposition or with subsequent migration of mobile salt components, dominated by sulfates of magnesium. striking variations in Cl and enrichments of Br, combined with diversity in sulfate species, provide further evidence of episodes during which temperatures, pH, and water to rock ratios underwent significant change. To first order, the sedimentary sequence examined to date is consistent with a uniform reference composition, modified by movement of major sulfates upward and of minor chlorides downward. This reference composition has similarities to martian soils, supplemented by sulfate anion and the alteration products of mafic igneous minerals. Lesser cementation in lower stratigraphic units is reflected in decreased energies for grinding with the Rock Abrasion Tool. Survival of soluble salts in exposed outcrop is most easily explained by absence of episodes of liquid H2O in this region since the time of crater formation. (c) 2005 Elsevier B.V. All rights reserved. C1 Lockheed Martin Space Syst, Denver, CO 80201 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. SUNY Stony Brook, Dept Geosci, Stony Brook, NY 11794 USA. Max Planck Inst Chem, D-55128 Mainz, Germany. Washington Univ, Dept Earth & Planetary Sci, St Louis, MO 63130 USA. Harvard Univ, Bot Museum, Cambridge, MA 02138 USA. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. SUNY Binghamton, Dept Geol Sci & Environ Studies, Binghamton, NY 13902 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Arizona State Univ, Dept Geol Sci, Tempe, AZ 85287 USA. Honeybee Robot, New York, NY 10012 USA. Univ Nevada, Reno, NV 89557 USA. Space Sci Inst, Boulder, CO 80301 USA. Johannes Gutenberg Univ Mainz, D-55128 Mainz, Germany. MIT, Cambridge, MA 02139 USA. Univ Tennessee, Dept Earth & Planetary Sci, Knoxville, TN 37996 USA. RP Clark, BC (reprint author), Lockheed Martin Space Syst, POB 179,MS S-8000, Denver, CO 80201 USA. EM benton.c.clark@LMCO.com NR 80 TC 244 Z9 248 U1 7 U2 40 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 NOV 30 PY 2005 VL 240 IS 1 BP 73 EP 94 DI 10.1016/j.epsl.2005.09.040 PG 22 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 990BJ UT WOS:000233717900003 ER PT J AU McLennan, SM Bell, JF Calvin, WM Christensen, PR Clark, BC de Souza, PA Farmer, J Farrand, WH Fike, DA Gellert, R Ghosh, A Glotch, TD Grotzinger, JP Hahn, B Herkenhoff, KE Hurowitz, JA Johnson, JR Johnson, SS Jolliff, B Klingelhofer, G Knoll, AH Learner, Z Malin, MC McSween, HY Pocock, J Ruff, SW Soderblom, LA Squyres, SW Tosca, NJ Watters, WA Wyatt, MB Yen, A AF McLennan, SM Bell, JF Calvin, WM Christensen, PR Clark, BC de Souza, PA Farmer, J Farrand, WH Fike, DA Gellert, R Ghosh, A Glotch, TD Grotzinger, JP Hahn, B Herkenhoff, KE Hurowitz, JA Johnson, JR Johnson, SS Jolliff, B Klingelhofer, G Knoll, AH Learner, Z Malin, MC McSween, HY Pocock, J Ruff, SW Soderblom, LA Squyres, SW Tosca, NJ Watters, WA Wyatt, MB Yen, A TI Provenance and diagenesis of the evaporite-bearing Burns formation, Meridiani Planum, Mars SO EARTH AND PLANETARY SCIENCE LETTERS LA English DT Article DE Mars; Meridiani Planum; diagenesis; geochemistry; sedimentology; provenance ID OPPORTUNITY ROVER; TERRA-MERIDIANI; MARTIAN SURFACE; EOLIAN DUNE; WHITE-SANDS; NEW-MEXICO; SPECTROMETER; INTERDUNE; HEMATITE; ORIGIN AB Impure reworked evaporitic sandstones, preserved on Meridiani Planum, Mars, are mixtures of roughly equal amounts of altered siliciclastic debris, of basaltic provenance (40 +/- 10% by mass), and chemical constituents, dominated by evaporitic minerals (jarosite, Mg-,, Ca-sulfates +/- chlorides +/- Fe-, Na-sulfates), hematite and possibly secondary silica (60 10%). These chemical constituents and their relative abundances are not an equilibrium evaporite assemblage and to a substantial degree have been reworked by aeolian and subaqueous transport. Ultimately they formed by evaporation of acidic waters derived from interaction with olivine-bearing basalts and subsequent diagenetic alteration. The rocks experienced an extended diagenetic history, with at least two and up to four distinct episodes of cementation, including stratigraphically restricted zones of recrystallization and secondary porosity, non-randomly distributed, highly spherical millimeter-scale hematitic concretions, millimeter-scale crystal molds, interpreted to have resulted from dissolution of a highly soluble evaporite mineral, elongate to sheet-like vugs and evidence for minor synsedimentary deformation (convolute and contorted bedding, possible teepee structures or salt ridge features). Other features that may be diagenetic, but more likely are associated with relatively recent meteorite impact, are meter-scale fracture patterns, veins and polygonal fractures on rock surfaces that cut across bedding. Crystallization of minerals that originally filled the molds, early cement and sediment deformation occurred syndepositionally or during early diagenesis. All other diagenetic features are consistent with formation during later diagenesis in the phreatic (fluid saturated) zone or capillary fringe of a groundwater table under near isotropic hydrological conditions such as those expected during periodic groundwater recharge. Textural evidence suggests that rapidly formed hematitic concretions post-date the primary mineral now represented by crystal molds and early pore-filling cements but pre-date secondary moldic and vug porosity. The second generation of cements followed formation of secondary porosity. This paragenetic sequence is consistent with an extended history of syndepositional through post-depositional diagenesis in the presence of a slowly fluctuating, chemically evolving, but persistently high ionic strength groundwater system. (c) 2005 Elsevier B.V. All rights reserved. C1 SUNY Stony Brook, Dept Geosci, Stony Brook, NY 11794 USA. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. Univ Nevada, Reno, NV 89557 USA. Arizona State Univ, Dept Geol Sci, Tempe, AZ 85287 USA. Lockheed Martin Corp, Littleton, CO 80127 USA. Johannes Gutenberg Univ Mainz, Inst Anorgan & Analyt Chem, D-55128 Mainz, Germany. Space Sci Inst, Vitoria, Brazil. MIT, Cambridge, MA 02139 USA. Max Planck Inst Chem, D-55128 Mainz, Germany. Univ Tennessee, Dept Earth & Planetary Sci, Knoxville, TN 37996 USA. US Geol Survey, Flagstaff, AZ 86001 USA. Washington Univ, Dept Earth & Planetary Sci, St Louis, MO 63130 USA. Harvard Univ, Bot Museum, Cambridge, MA 02138 USA. Malin Space Sci Syst, San Diego, CA 92191 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP McLennan, SM (reprint author), SUNY Stony Brook, Dept Geosci, Stony Brook, NY 11794 USA. EM scott.mclennan@sunysb.edu RI Hurowitz, Joel/A-8862-2008; Glotch, Timothy/B-6829-2008; de Souza, Paulo/B-8961-2008; Fike, David/D-3634-2011; Johnson, Jeffrey/F-3972-2015 OI de Souza, Paulo/0000-0002-0091-8925; Fike, David/0000-0003-2848-0328; NR 69 TC 299 Z9 301 U1 8 U2 70 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 NOV 30 PY 2005 VL 240 IS 1 BP 95 EP 121 DI 10.1016/j.epsl.2005.09.041 PG 27 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 990BJ UT WOS:000233717900004 ER PT J AU Fernandez-Remolar, DC Morris, RV Gruener, JE Amils, R Knoll, AH AF Fernandez-Remolar, DC Morris, RV Gruener, JE Amils, R Knoll, AH TI The Rio Tinto basin, Spain: Mineralogy, sedimentary geobiology, and implications for interpretation of outcrop rocks at Meridiani Planum, Mars SO EARTH AND PLANETARY SCIENCE LETTERS LA English DT Article DE Mars; Meridiani Planum; Rio Tinto basin; geobiology; hematite; chemical weathering ID EXTREME ACIDIC ENVIRONMENT; SOUTHWEST SPAIN; RIVER; HEMATITE; JAROSITE; WATER; IRON; SPECTROMETER; MOSSBAUER; DRAINAGE AB Exploration by the NASA rover Opportunity has revealed sulfate- and hematite-rich sedimentary rocks exposed in craters and other surface features of Meridiani Planum, Mars. Modem, Holocene, and Plio-Pleistocene deposits of the Rio Tinto, southwestern Spain, provide at least a partial environmental analog to Meridiani Planum rocks, facilitating our understanding of Meridiani mineral precipitation and diagenesis, while informing considerations of martian astrobiology. Oxidation, thought to be biologically mediated, of pyritic ore bodies by groundwaters in the source area of the Rio Tinto generates headwaters enriched in sulfuric acid and ferric iron. Seasonal evaporation of river water drives precipitation of hydronium jarosite and schwertmannite, while (Mg,Al,Fe3+)-copiapite, coquimbite, gypsum, and other sulfate minerals precipitate nearby as efflorescences where locally variable source waters are brought to the surface by capillary action. During the wet season, hydrolysis of sulfate salts results in the precipitation of nanophase goethite. Holocene and Plio-Pleistocene terraces show increasing goethite crystallinity and then replacement of goethite with hematite through time. Hematite in Meridiani spherules also formed during diagenesis, although whether these replaced precursor goethite or precipitated directly from groundwaters is not known. The retention of jarosite and other soluble sulfate salts suggests that water limited the diagenesis of Meridiam rocks. Diverse prokaryotic and eukaryotic microorganisms inhabit acidic and seasonally dry Rio Tinto environments. Organic matter does not persist in Rio Tinto sediments, but biosignatures imparted to sedimentary rocks as macroscopic textures of coated microbial streamers, surface blisters formed by biogenic gas, and microfossils preserved as casts and molds in iron oxides help to shape strategies for astrobiological investigation of Meridiani outcrops. (c) 2005 Elsevier B.V. All rights reserved. C1 CSIC, INTA, Ctr Astrobiol, Torrejon De Ardoz 28850, Spain. NASA, Lyndon B Johnson Space Ctr, Astromat Res Off, Houston, TX 77058 USA. Harvard Univ, Dept Organism & Evolutionary Biol, Cambridge, MA 02138 USA. CSIC, Ctr Mol Biol, E-28049 Madrid, Spain. RP Fernandez-Remolar, DC (reprint author), CSIC, INTA, Ctr Astrobiol, Ctra Ajalvir Km 4, Torrejon De Ardoz 28850, Spain. EM fernandezrd@inta.es NR 42 TC 154 Z9 162 U1 6 U2 44 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 NOV 30 PY 2005 VL 240 IS 1 BP 149 EP 167 DI 10.1016/j.epsl.2005.09.043 PG 19 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 990BJ UT WOS:000233717900006 ER PT J AU Morris, RV Ming, DW Graff, TG Arvidson, RE Bell, JF Squyres, SW Mertzman, SA Gruener, JE Golden, DC Le, L Robinson, GA AF Morris, RV Ming, DW Graff, TG Arvidson, RE Bell, JF Squyres, SW Mertzman, SA Gruener, JE Golden, DC Le, L Robinson, GA TI Hematite spherules in basaltic tephra altered under aqueous, acid-sulfate conditions on Mauna Kea volcano, Hawaii: Possible clues for the occurrence of hematite-rich spherules in the Burns formation at Meridiani Planum, Mars SO EARTH AND PLANETARY SCIENCE LETTERS LA English DT Article DE Mars; Meridiani Planum; Mars Exploration Rover; spherule; hematite; concretions; sulfate ID OPPORTUNITY ROVER; TERRESTRIAL ANALOG; SPECTROMETER; MINERALOGY; SOILS; HYDROLYSIS; PARTICLES; SAMPLES; ROCKS; WATER AB Iron-rich spherules (> 90% Fe2O3 from electron microprobe analyses) similar to 10-100 mu m in diameter are found within sulfate-rich rocks formed by aqueous, acid-sulfate alteration of basaltic tephra on Mauna Kea volcano, Hawaii. Although some spherules are nearly pure Fe, most have two concentric compositional zones, with the core having a higher Fe/Al ratio than the rim. Oxide totals less than 100% (93-99%) suggest structural H2O and/or OH-1. The transmission Mossbauer spectrum of a spherule-rich separate is dominated by a hematite (alpha-Fe2O3) sextet whose peaks are skewed toward zero velocity. Skewing is consistent with Al3+ for Fe3+ substitution and structural H2O and/or OH-1. The grey color of the spberules implies specular hematite. Whole-rock powder X-ray diffraction spectra are dominated by peaks from smectite and the hydroxy sulfate mineral natroalunite as alteration products and plagioclase feldspar that was present in the precursor basaltic tephra. Whether spherule formation proceeded directly from basaltic material in one event (dissolution of basaltic material and precipitation of hematite spherules) or whether spherule formation required more than one event (formation of Fe-bearing sulfate rock and subsequent hydrolysis to hematite) is not currently constrained. By analogy, a formation pathway for the hematite spherules in sulfate-rich outcrops at Meridiani Planum on Mars (the Burns formation) is aqueous alteration of basaltic precursor material under acid-sulfate conditions. Although hydrothermal conditions are present on Mauna Kea, such conditions may not be required for spherule formation on Mars if the time interval for hydrolysis at lower temperatures is sufficiently long. (c) 2005 Elsevier B.V. All rights reserved. C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Arizona State Univ, Tempe, AZ 85287 USA. Washington Univ, St Louis, MO 63130 USA. Cornell Univ, Ithaca, NY 14853 USA. Franklin & Marshall Coll, Lancaster, PA 17604 USA. Jacobs Sverdrup Technol, Houston, TX 77058 USA. RP NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. EM richard.v.morris@nasa.gov NR 26 TC 51 Z9 51 U1 4 U2 15 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 NOV 30 PY 2005 VL 240 IS 1 BP 168 EP 178 DI 10.1016/j.epsl.2005.09.044 PG 11 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 990BJ UT WOS:000233717900007 ER PT J AU Knoll, AH Carr, M Clark, B Marais, DJD Farmer, JD Fischer, WW Grotzinger, JP McLennan, SM Malin, M Schroder, C Squyres, S Tosca, NJ Wdowiak, T AF Knoll, AH Carr, M Clark, B Marais, DJD Farmer, JD Fischer, WW Grotzinger, JP McLennan, SM Malin, M Schroder, C Squyres, S Tosca, NJ Wdowiak, T TI An astrobiological perspective on Meridiani Planum SO EARTH AND PLANETARY SCIENCE LETTERS LA English DT Article DE Mars; Meridiani Planum; astrobiology; environmental history; microbiology ID MARTIAN METEORITE ALH84001; EARLY MARS; LOW-TEMPERATURES; TERRA-MERIDIANI; WATER; LIFE; PH; SURFACE; HEMATITE; BACTERIA AB Sedimentary rocks exposed in the Meridiani Planum region of Mars record aqueous and eolian deposition in ancient dune and interdune playa-like environments that were arid, acidic, and oxidizing. On Earth, microbial populations have repeatedly adapted to low pH and both episodic and chronic water limitation, suggesting that, to a first approximation, the Meridiani plain may have been habitable during at least part of the interval when deposition and early diagenesis took place. On the other hand, the environmental conditions inferred for Meridiani deposition would have posed a challenge for prebiotic chemical reactions thought to have played a role in the origin of life on Earth. Orbital observations suggest that the combination of sulfate minerals and hematite found in Meridiani rocks may be unusual on the martian surface; however, there is reason to believe that acidity, aridity, and oxidizing conditions were broadly distributed on ancient Mars. When these conditions were established and how much environmental heterogeneity existed on early Mars remain to be determined. Because sulfates and iron oxides can preserve detailed geochemical records of environmental history as well as chemical, textural and microfossil signatures of biological activity, Meridiani Planum is an attractive candidate for Mars sample return. (c) 2005 Elsevier B.V. All rights reserved. C1 Harvard Univ, Dept Organism & Evolutionary Biol, Cambridge, MA 02138 USA. US Geol Survey, Menlo Pk, CA 94025 USA. Ma Lockheed Martin Corp, Littleton, CO 80127 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Arizona State Univ, Dept Geol Sci, Tempe, AZ 85287 USA. MIT, Dept Earth Atmospher & Planetary Sci, Cambridge, MA 02139 USA. SUNY Stony Brook, Dept Geosci, Stony Brook, NY 11794 USA. Malin Space Sci Syst, San Diego, CA 92191 USA. Johannes Gutenberg Univ Mainz, Inst Anorgan & Analyt Chem, D-55128 Mainz, Germany. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. Univ Alabama Birmingham, Dept Phys, Birmingham, AL 35294 USA. RP Knoll, AH (reprint author), Harvard Univ, Dept Organism & Evolutionary Biol, Cambridge, MA 02138 USA. EM aknoll@oeb.harvard.edu RI Schroder, Christian/B-3870-2009 OI Schroder, Christian/0000-0002-7935-6039 NR 94 TC 78 Z9 80 U1 1 U2 11 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 NOV 30 PY 2005 VL 240 IS 1 BP 179 EP 189 DI 10.1016/j.epsl.2005.09.045 PG 11 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 990BJ UT WOS:000233717900008 ER PT J AU Canuto, VM Dubovikov, MS Cheng, Y AF Canuto, VM Dubovikov, MS Cheng, Y TI Entrainment: Local and non-local turbulence models with double diffusion SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID MEDITERRANEAN OUTFLOW; VERTICAL DIFFUSIVITIES; CONTINENTAL-SLOPE; OCEAN TURBULENCE; DENMARK STRAIT; MOMENTUM; FLOWS; SEA; DYNAMICS; OVERFLOW AB Taylor's entrainment equation contains the entrainment function E that has traditionally been treated heuristically, as attested by 30 different expressions for E(Ri) available in the literature. Using a model independent procedure, we first derive the new relation: E = 2P(s)h (u) over bar (-3) which expresses E in terms of P-s, the shear production (of turbulent kinetic energy) averaged across the interface of the gravity current whose thickness and mean velocity are denoted by h and u. Second, using a turbulence model for the turbulence kinetic energy K and its rate of dissipation epsilon (K-epsilon model, integrated across the flow), we compute P-s to express E in terms of the Richardson number Ri and the density ratio R-rho characterizing double-diffusion. Third, we show that in the local (along the flow) case, the model reproduces the Ellison and Turner (1959) data while the non-local case reproduces the data by Princevac et al. (2005) which are up to ten times larger than the ET data. C1 NASA, Goddard Inst Space Studies, New York, NY 10025 USA. Columbia Univ, Dept Appl Math & Phys, New York, NY USA. Columbia Univ, Ctr Climate Syst Res, New York, NY USA. RP Canuto, VM (reprint author), NASA, Goddard Inst Space Studies, 2880 Broadway, New York, NY 10025 USA. EM vcanuto@giss.nasa.gov NR 31 TC 4 Z9 4 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 NOV 30 PY 2005 VL 32 IS 22 AR L22604 DI 10.1029/2005GL023771 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 993EG UT WOS:000233935600001 ER PT J AU Carabajal, CC Harding, DJ AF Carabajal, CC Harding, DJ TI ICESat validation of SRTM C-band digital elevation models SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article AB The Geoscience Laser Altimeter System (GLAS) on the Ice, Cloud, and land Elevation Satellite (ICESat) provides a globally-distributed data set well suited for evaluating the vertical accuracy of Shuttle Radar Topography Mission (SRTM) digital elevation models (DEMs). The horizontal error (2.4 +/- 7.3 m) and vertical error (0.04 +/- 0.13 m per degree of incidence angle) for the ICESat data used are small compared to those for SRTM. Using GLAS echo waveforms we document differences between the SRTM C-band phase center and the highest, centroid, and lowest elevations within ICESat laser footprints in the western United States. In areas of low relief and sparse tree cover, the mean and standard deviation of elevation differences between the ICESat centroid and SRTM are -0.60 +/- 3.46 m. The differences are -5.61 +/- 15.68 m in high relief, sparse tree cover areas, and -3.53 +/- 8.04 m in flat areas with dense tree cover. The largest differences occur in rugged, densely-vegetated regions. C1 NASA, Goddard Space Flight Ctr, Space Geodesy Lab, NVI Inc, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Planetary Geodynam Lab, Greenbelt, MD 20771 USA. RP Carabajal, CC (reprint author), NASA, Goddard Space Flight Ctr, Space Geodesy Lab, NVI Inc, Code 697, Greenbelt, MD 20771 USA. EM Claudia@bowie.gsfc.nasa.gov RI Harding, David/F-5913-2012 NR 11 TC 64 Z9 69 U1 1 U2 6 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 NOV 30 PY 2005 VL 32 IS 22 AR L22S01 DI 10.1029/2005GL023957 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 993EG UT WOS:000233935600004 ER PT J AU Kostiuk, T Livengood, TA Hewagama, T Sonnabend, G Fast, KE Murakawa, K Tokunaga, AT Annen, J Buhl, D Schmulling, F AF Kostiuk, T Livengood, TA Hewagama, T Sonnabend, G Fast, KE Murakawa, K Tokunaga, AT Annen, J Buhl, D Schmulling, F TI Titan's stratospheric zonal wind, temperature, and ethane abundance a year prior to Huygens insertion SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID ATMOSPHERE; SPECTROSCOPY; DYNAMICS; PLANETS; LINES AB Saturn's satellite, Titan, may have stratospheric winds up to similar to 210 m/s, circling Titan in similar to 1 terrestrial day compared to its 16-day rotation. Theoretical models explaining such super-rotating winds are not well constrained by observations of Titan or a similar slow rotator, Venus. We report measurements taken in December 2003 of zonal wind near Titan's equatorial region, including the Cassini Huygens probe entry latitude. Super-rotating prograde zonal winds of 190 +/- 90 m/s near 220 km altitude are found from Doppler-shifted C2H6 gas emission near 12 mm, confirming high wind velocity even near the equator. Stratospheric temperature constraints and ethane abundance (8 +/- 3 ppm) also are retrieved. Results are not inconsistent with earlier measurements and with recent Cassini CIRS results, but indicate possible variations between Titan's hemispheres. Differences in east and west C2H6 spectral line shapes can be accounted for by different vertical distributions of either C2H6 abundance or temperature or by unidentified dynamical effects. C1 NASA, Goddard Space Flight Ctr, Natl Res Council, Greenbelt, MD 20771 USA. Univ Space Res Assoc, Washington, DC 20036 USA. Univ Maryland, Dept Astron, College Pk, MD 20742 USA. Natl Astron Observ Japan, Subaru Telescope, Hilo, HI 96720 USA. Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA. Univ Cologne, Inst Phys 1, D-50937 Cologne, Germany. RP Kostiuk, T (reprint author), Natl Astron Observ Japan, Subaru Telescope, Hilo, HI 96720 USA. EM kostiuk@gsfc.nasa.gov RI Hewagama, T/C-8488-2012; Kostiuk, Theodor/A-3077-2014 NR 28 TC 21 Z9 21 U1 0 U2 3 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 NOV 30 PY 2005 VL 32 IS 22 AR L22205 DI 10.1029/2005GL023897 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 993EG UT WOS:000233935600002 ER PT J AU Bills, BG AF Bills, BG TI Variations in the rotation rate of Venus due to orbital eccentricity modulation of solar tidal torques SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID ATMOSPHERIC ANGULAR-MOMENTUM; LONG-TERM EVOLUTION; INNER-CORE; EARTHS CORE; GEOMAGNETIC-FIELD; RESONANT ROTATION; HARMONIC-ANALYSIS; FORCED NUTATIONS; WESTWARD DRIFT; CW RADAR AB [1] The rotational state of Venus is presumably determined by a balance between two different solar tidal torques: an atmospheric thermal tide yields a torque which acts in the same direction as the retrograde rotation of Venus and a gravitational solid body tide yields a torque which opposes the current rotation. The strengths of these opposing torques both depend on the eccentricity of the orbit of Venus but with different sensitivities. Thus variations in the orbital eccentricity cause fluctuations in the rotation rate at which the tidal torques balance. If Venus is considered to be a single rigid body, the rotational velocity will change by amounts equivalent to similar to 1 km/yr at the equator, over timescales of 10 6 years. Allowance for differential rotation between the core, mantle, and atmosphere increases the range over which the solid surface rotation rate varies. For plausible values of the strength of viscous coupling at the atmosphere-mantle boundary and the core-mantle boundary the variations in solid surface rotational velocity can be 2 - 3 times larger than in the rigid coupling case. When these long-period forced variations in rotation rate are considered, the present rotation rate of Venus is seen to be close enough to a resonant spin-orbit interaction with the Earth that it may occasionally pass through that resonance. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Bills, BG (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM bbills@ucsd.edu RI Bills, Bruce/C-1156-2008 NR 97 TC 2 Z9 2 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 NOV 30 PY 2005 VL 110 IS E11 AR E11007 DI 10.1029/2003JE002190 PG 18 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 993OJ UT WOS:000233963100001 ER PT J AU Johnson, PV Malone, CP Kanik, I Tran, K Khakoo, MA AF Johnson, PV Malone, CP Kanik, I Tran, K Khakoo, MA TI Integral cross sections for the direct excitation of the A (3)Sigma(+)(u), B (3)Pi(g), W (3)Delta(u), B ' (3)Sigma(-)(u), a ' 1 Sigma(-)(u), a (1)Pi(g), w (1)Delta(u), and C (3)Pi(u) electronic states in N-2 by electron impact SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID BIRGE-HOPFIELD BANDS; DIATOMIC-MOLECULES; RADIATIVE LIFETIME; VACUUM-ULTRAVIOLET; METASTABLE STATES; NITROGEN MOLECULE; INCIDENT ENERGIES; N2; LYMAN; SCATTERING AB [1] Integral cross sections for electron impact excitation out of the ground state ( X (1)Sigma(g)(+)) to the A (3)Sigma(u)(+), B (3)Pi(g), W (3)Delta(u), B' (3)Sigma(u)(-), a' (1)Sigma(u)(-), a (1)Pi(g), w (1)Delta(u), and C (3)Pi(u) states in N-2 are reported at incident energies ranging between 10 and 100 eV. These data have been derived by integrating differential cross sections previously reported by this group. New differential cross section measurements for the a (1)Pi(g) state at 200 eV are also presented to extend the range of the reported integral cross sections for this state, which is responsible for the emissions of the Lyman-Birge-Hopfield band system ( a (1)Pi(g) --> X (1)Sigma(g)(+)). The present results are compared and critically evaluated against existing cross sections. In general, the present cross sections are smaller than previous results at low impact energies from threshold through the excitation function peak regions. These lower cross sections have potentially significant implications on our understanding of UV emissions in the atmospheres of Earth and Titan. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Calif State Univ Fullerton, Dept Phys, Fullerton, CA 92834 USA. RP Johnson, PV (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM paul.v.johnson@jpl.nasa.gov 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 57 TC 30 Z9 30 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 NOV 30 PY 2005 VL 110 IS A11 AR A11311 DI 10.1029/2005JA011295 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 993OQ UT WOS:000233963800006 ER PT J AU Lepping, RP Wu, CC AF Lepping, RP Wu, CC TI Extreme interplanetary rotational discontinuities at 1 AU SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID FIELD DIRECTIONAL DISCONTINUITIES; SOLAR-WIND; MAGNETIC-FIELD; TANGENTIAL DISCONTINUITIES; PLASMA; IDENTIFICATION; MAGNETOPAUSE; SPACECRAFT; CLUSTER; WAVES AB [1] This study is concerned with the identification and description of a special subset of four Wind interplanetary rotational discontinuities ( from an earlier study of 134 directional discontinuities by Lepping et al. ( 2003)) with some "extreme'' characteristics, in the sense that every case has ( 1) an almost planar current sheet surface, ( 2) a very large discontinuity angle (omega), ( 3) at least moderately strong normal field components (> 0.8 nT), and ( 4) the overall set has a very broad range of transition layer thicknesses, with one being as thick as 50 R-E and another at the other extreme being 1.6 R-E, most being much thicker than are usually studied. Each example has a well-determined surface normal (n) according to minimum variance analysis and corroborated via time delay checking of the discontinuity with observations at IMP 8 by employing the local surface planarity. From the variance analyses, most of these cases had unusually large ratios of intermediate-to-minimum eigenvalues (lambda(I)/lambda(min)), being on average 32 for three cases ( with a fourth being much larger), indicating compact current sheet transition zones, another ( the fifth) extreme property. For many years there has been a controversy as to the relative distribution of rotational (RDs) to tangential discontinuities (TDs) in the solar wind at 1 AU ( and elsewhere, such as between the Sun and Earth), even to the point where some authors have suggested that RDs with large \B-n\s are probably not generated or, if generated, are unstable and therefore very rare. Some of this disagreement apparently has been due to the different selection criteria used, e. g., some allowed eigenvalue ratios (lambda(I)/lambda(min)) to be almost an order of magnitude lower than 32 in estimating n, usually introducing unacceptable error in n and therefore also in \B-n\. However, we suggest that RDs may not be so rare at 1 AU, but good quality cases ( where \B-n\ confidently exceeds the error in \B-n\) appear to be uncommon, and further, cases of large \B-n\ may indeed be rare. Finally, the issue of estimating the number of RDs-to-TDs was revisited using the full 134 events of the original Lepping et al. ( 2003) study ( which utilized the RDs' propagation speeds for this estimation, an unconventional approach) but now by considering only normal field components, the more conventional approach. This resulted in slightly different conclusions, depending on specific assumptions used, making the unconventional approach suspect. C1 NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Greenbelt, MD 20771 USA. Univ Alabama, Ctr Space Plasma & Aeron Res, Huntsville, AL 35899 USA. RP Lepping, RP (reprint author), NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Code 696-0, Greenbelt, MD 20771 USA. EM ronald.p.lepping@nasa.gov NR 30 TC 1 Z9 1 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 NOV 30 PY 2005 VL 110 IS A11 AR A11105 DI 10.1029/2004JA010518 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 993OQ UT WOS:000233963800001 ER PT J AU Haverd, V Toon, GC Griffith, DWT AF Haverd, V Toon, GC Griffith, DWT TI Evidence for altitude-dependent photolysis-induced O-18 isotopic fractionation in stratospheric ozone SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID HEAVY OZONE; ENRICHMENTS; ATMOSPHERE; SPECTRA AB We present vertical profiles of O-18 fractionations in ozone, measured by balloon-borne infrared remote sensing between 15 and 40 km. The magnitudes of the (OOO)-O-16-O-16-O-18 (O-668(3)) and (OOO)-O-16-O-18-O-16 (O-686(3)) fractionations are 13.5 +/- 2.7% and 7.7 +/- 2.2%, averaged over the 20 - 35 km altitude range, in good agreement with previous atmospheric measurements by mass spectrometry and both infrared and far infrared remote sensing spectroscopy. We use our fractionation profiles, together with known fractionation effects of the ozone formation reaction, to deduce fractionations attributable to photolysis. These photolytic fractionation profiles show significant increases with altitude (3.5 +/- 2.2% and 4.0 +/- 1.6% for O-668(3) and O-686(3) respectively over the 20 - 35 km altitude range), indicating that the ozone formation reaction alone does not account for the observed enrichments. C1 Univ Wollongong, Dept Chem, Wollongong, NSW 2522, Australia. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Haverd, V (reprint author), Univ Wollongong, Dept Chem, Wollongong, NSW 2522, Australia. EM vanessah@uow.edu.au RI haverd, vanessa/G-8683-2011 NR 16 TC 12 Z9 12 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 NOV 29 PY 2005 VL 32 IS 22 AR L22808 DI 10.1029/2005GL024049 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 993EF UT WOS:000233935500002 ER PT J AU Kwok, R Maslowski, W Laxon, SW AF Kwok, R Maslowski, W Laxon, SW TI On large outflows of Arctic sea ice into the Barents Sea SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID FRAM STRAIT; TRANSPORTS; REGION; COVER; MASS AB Winter outflows of Arctic sea ice into the Barents Sea are estimated using a 10-year record of satellite ice motion and thickness. The mean winter volume export through the Svalbard/Franz Josef Land passage is 40 km(3), and ranges from - 280 km(3) to 340 km(3). A large outflow in 2003 is preconditioned by an unusually high concentration of thick perennial ice over the Nansen Basin at the end of the 2002 summer. With a deep atmospheric low situated over the eastern Barents Sea in winter, the result is an increased export of Arctic ice. The Oct-Mar ice area flux, at 110 x 10(3) km(2), is not only unusual in magnitude but also remarkable in that > 70% of the area is multiyear ice; the ice volume flux at similar to 340 km(3) is almost one-fifth of the ice flux through the Fram Strait. Another large outflow of Arctic sea ice through this passage, comparable to that in 2003, is found in 1996. This southward flux of sea ice represents one of two major sources of freshwater in the Barents Sea; the other is the eastward flux of water via the Norwegian Coastal Current. The possible consequences of variable freshwater input on the Barents Sea hydrography and its impact on transformation of Atlantic Water en route to the Arctic Ocean are examined with a 25-year coupled ice-ocean model. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. UCL, Dept Space & Climate Phys, London WC1E 6BT, England. RP Kwok, R (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. RI Kwok, Ron/A-9762-2008; Laxon, Seymour/C-1644-2008 OI Kwok, Ron/0000-0003-4051-5896; NR 13 TC 28 Z9 28 U1 0 U2 11 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 NOV 29 PY 2005 VL 32 IS 22 AR L22503 DI 10.1029/2005GL024485 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 993EF UT WOS:000233935500004 ER PT J AU Sirota, JM Bae, S Millar, P Mostofi, D Webb, C Schutz, B Luthcke, S AF Sirota, JM Bae, S Millar, P Mostofi, D Webb, C Schutz, B Luthcke, S TI The transmitter pointing determination in the Geoscience Laser Altimeter System SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article AB The determination of accurate elevation data using laser altimetry relies on accurate knowledge of the instrument pointing angle. The Geoscience Laser Altimeter System (GLAS) on the Ice, Cloud and land Elevation Satellite (ICESat) uses a novel system for determination of the laser pointing vector. In this paper we describe this system, as well as the method used to process its data, which are required to meet ICESat's science objectives. We discuss the necessary modifications to processing techniques, implemented to optimize accuracy for the various operating conditions. Results to date are compared to calibration/ validation data to assess their accuracy. We show that the stated requirements have been met for near nominal operating conditions. C1 Sigma Space Corp, Lanham, MD 20706 USA. Univ Texas, Ctr Space Res, Austin, TX 78759 USA. NASA, Goddard Space Flight Ctr, Space Geodesy Lab, Greenbelt, MD 20771 USA. RP Sirota, JM (reprint author), Sigma Space Corp, 4801 Forbes Blvd, Lanham, MD 20706 USA. EM marcos.sirota@sigmaspace.com RI Luthcke, Scott/D-6283-2012 NR 11 TC 13 Z9 15 U1 1 U2 2 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 NOV 29 PY 2005 VL 32 IS 22 AR L22S11 DI 10.1029/2005GL024005 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 993EF UT WOS:000233935500001 ER PT J AU Qu, LW Veca, LM Lin, Y Kitaygorodskiy, A Chen, BL McCall, AM Connell, JW Sun, YP AF Qu, LW Veca, LM Lin, Y Kitaygorodskiy, A Chen, BL McCall, AM Connell, JW Sun, YP TI Soluble nylon-functionalized carbon nanotubes from anionic ring-opening polymerization from nanotube surface SO MACROMOLECULES LA English DT Article ID TRANSFER RADICAL POLYMERIZATION; NANOCOMPOSITES; POLYSTYRENE; MORPHOLOGY; DISPERSION; COMPOSITE; POLYMERS; WATER C1 Clemson Univ, Dept Chem, Clemson, SC 29634 USA. Clemson Univ, Lab Emerging Mat & Technol, Clemson, SC 29634 USA. NASA, Langley Res Ctr, Adv Mat & Proc Branch, Hampton, VA 23681 USA. RP Sun, YP (reprint author), Clemson Univ, Dept Chem, Clemson, SC 29634 USA. RI Veca, Lucia/A-4622-2012 NR 34 TC 72 Z9 78 U1 0 U2 21 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD NOV 29 PY 2005 VL 38 IS 24 BP 10328 EP 10331 DI 10.1021/ma051762n PG 4 WC Polymer Science SC Polymer Science GA 987NP UT WOS:000233524900056 ER PT J AU Fischer, G Shah, M Tubiello, FN van Velhuizen, H AF Fischer, G Shah, M Tubiello, FN van Velhuizen, H TI Socio-economic and climate change impacts on agriculture: an integrated assessment, 1990-2080 SO PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES LA English DT Article DE agriculture; crop production; climate change; food security; sub-Saharan Africa; risk of hunger ID AIR CO2 ENRICHMENT; COUPLED MODEL; SEA-ICE; ELEVATED CO2; LAND-USE; SIMULATION; CROP; US; SCENARIOS; RESPONSES AB A comprehensive assessment of the impacts of climate change on agro-ecosystems over this century is developed, up to 2080 and at a global level, albeit with significant regional detail. To this end an integrated ecological-economic modelling framework is employed, encompassing climate scenarios, agro-ecological zoning information, socio-economic drivers, as well as world food trade dynamics. Specifically, global simulations are performed using the FAO/IIASA agro-ecological zone model, in conjunction with IIASAs global food system model, using climate variables from five different general circulation models, under four different socio-economic scenarios from the intergovernmental panel on climate change. First, impacts of different scenarios of climate change on bio-physical soil and crop growth determinants of yield are evaluated on a 5' X 5' latitude/longitude global grid; second, the extent of potential agricultural land and related potential crop production is computed. The detailed bio-physical results are then fed into an economic analysis, to assess how climate impacts may interact with alternative development pathways, and key trends expected over this century for food demand and production, and trade, as well as key composite indices such as risk of hunger and malnutrition, are computed. This modelling approach connects the relevant bio-physical and socioeconomic variables within a unified and coherent framework to produce a global assessment of food production and security under climate change. The results from the study suggest that critical impact asymmetries due to both climate and socio-economic structures may deepen current production and consumption gaps between developed and developing world; it is suggested that adaptation of agricultural techniques will be central to limit potential damages under climate change. C1 Int Inst Appl Syst Anal, A-2361 Laxenburg, Austria. Columbia Univ, Goddard Inst Space Studies, New York, NY 10027 USA. RP Fischer, G (reprint author), Int Inst Appl Syst Anal, A-2361 Laxenburg, Austria. EM fisher@iiasa.ac.at NR 47 TC 300 Z9 309 U1 20 U2 166 PU ROYAL SOCIETY PI LONDON PA 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 0962-8436 J9 PHILOS T ROY SOC B JI Philos. Trans. R. Soc. B-Biol. Sci. PD NOV 29 PY 2005 VL 360 IS 1463 BP 2067 EP 2083 DI 10.1098/rstb.2005.1744 PG 17 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 986CS UT WOS:000233427400008 PM 16433094 ER PT J AU Parry, M Rosenzweig, C Livermore, M AF Parry, M Rosenzweig, C Livermore, M TI Climate change, and risk global food supply of hunger SO PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES LA English DT Article DE climate change; agriculture; food supply; crop yields; food prices; risk of hunger ID ATMOSPHERIC CARBON-DIOXIDE; SCENARIOS; MODEL; EMISSIONS; RESPONSES AB This paper reports the results of a series of research projects which have aimed to evaluate the implications of climate change for food production and risk of hunger. There are three sets of results: (a) for IS92a (previously described as a 'business-as-usual' climate scenario); (b) for stabilization scenarios at 550 and 750 ppm and (c) for Special Report on Emissions Scenarios (SRES). The main conclusions are: (i) the region of greatest risk is Africa; (ii) stabilization at 750 ppm avoids some but not most of the risk, while stabilization at 550 ppm avoids most of the risk and (iii) the impact of climate change on risk of hunger is influenced greatly by pathways of development. For example, a SRES B2 development pathway is characterized by much lower levels of risk than A2; and this is largely explained by differing levels of income and technology not by differing amounts of climate forcing. C1 UK Metrol Off, JHadley Ctr, Exeter EX1 3PB, Devon, England. Goddard Inst Space Studies, New York, NY 10025 USA. Univ E Anglia, Climat Res Unit, Norwich NR4 7TJ, Norfolk, England. RP Parry, M (reprint author), UK Metrol Off, JHadley Ctr, Fitzroy Rd, Exeter EX1 3PB, Devon, England. EM parryml@aol.com NR 36 TC 147 Z9 157 U1 8 U2 45 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 NOV 29 PY 2005 VL 360 IS 1463 BP 2125 EP 2138 DI 10.1098/rstb.2005.1751 PG 14 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 986CS UT WOS:000233427400012 PM 16433098 ER PT J AU Yang, G Tang, J Kato, S Zhang, Q Qin, LC Woodson, M Liu, J Kim, JW Lillehei, PT Park, C Zhou, O AF Yang, G Tang, J Kato, S Zhang, Q Qin, LC Woodson, M Liu, J Kim, JW Lillehei, PT Park, C Zhou, O TI Magnetic nanowire based high resolution magnetic force microscope probes (vol 87, pg 123507, 2005) SO APPLIED PHYSICS LETTERS LA English DT Correction C1 Univ N Carolina, Dept Phys & Astron, Chapel Hill, NC 27599 USA. Natl Inst Mat Sci, Tsukuba, Ibaraki 3050047, Japan. Univ N Carolina, Curriculum Appl & Mat Sci, Chapel Hill, NC 27599 USA. Duke Univ, Dept Chem, Durham, NC 27708 USA. Sci & Technol Corp, Hampton, VA 23666 USA. NASA, Langley Res Ctr, Adv Mat & Proc Branch, Hampton, VA 23681 USA. NASA, Langley Res Ctr, Natl Inst Aerosp, Hampton, VA 23681 USA. RP Yang, G (reprint author), Univ N Carolina, Dept Phys & Astron, Chapel Hill, NC 27599 USA. EM zhou@physics.unc.edu RI Kim, Jae-Woo/A-8314-2008; Liu, Jie/B-4440-2010 OI Liu, Jie/0000-0003-0451-6111 NR 1 TC 0 Z9 0 U1 0 U2 0 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 NOV 28 PY 2005 VL 87 IS 22 AR 229901 DI 10.1063/1.2132522 PG 1 WC Physics, Applied SC Physics GA 986OA UT WOS:000233458400093 ER PT J AU Eastwood, JP Balogh, A Lucek, EA Mazelle, C Dandouras, I AF Eastwood, JP Balogh, A Lucek, EA Mazelle, C Dandouras, I TI Quasi-monochromatic ULF foreshock waves as observed by the four-spacecraft Cluster mission: 1. Statistical properties SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID EARTHS BOW SHOCK; LOW-FREQUENCY WAVES; PARTICLE INTERACTION UPSTREAM; GYROPHASE-BUNCHED IONS; SOLAR-WIND IONS; GYRATING IONS; TERRESTRIAL FORESHOCK; EXCITATION MECHANISM; SUPRATHERMAL IONS; FAR UPSTREAM AB [1] Cluster data are used to study the statistics of a particular type of foreshock wave: quasi-monochromatic ultra-low-frequency (ULF) waves with characteristic periods of 30 s in the spacecraft frame. On the basis of a large set of foreshock observations made in 2001 with spacecraft separations similar to 600 km, the intrinsic properties of the waves are found using a cross-correlation timing analysis. This method, which allows the solar wind rest frame properties of the waves to be calculated with fewer assumptions when compared to previous dual spacecraft analysis, is described in detail. The performance of minimum variance analysis (MVA) as a wave analysis tool is investigated experimentally using this multispacecraft analysis. MVA estimates of propagation direction are shown to diverge from the multispacecraft estimate in the limit of linear wave polarization. Theoretical estimates of MVA error are also compared to the observations. Previously established wave properties derived from ISEE are independently tested; it is found that statistically, the waves propagate at frequencies an order of magnitude below the ion cyclotron frequency in the solar wind rest frame and have wavelengths of the order of an Earth radius. However, these statements mask the fact that there is significant variation about these average values that is physical in nature. The data are plotted in the omega - k plane and the average frequency and wave number are used to experimentally identify the "average'' resonant beam speed. This beam speed is an order of magnitude greater than the local Alfven speed in the solar wind rest frame. Furthermore, histograms of the inferred beam speed normalized to the solar wind speed are presented and compared to previously published plasma data. Finally, the spacecraft frame wave period is found to be proportional to the magnetic field strength in a manner consistent with previous analyses. C1 NASA, Goddard Space Flight Ctr, Geospace Phys Branch, Lab Solar & Space Phys, Greenbelt, MD 20771 USA. Univ London Imperial Coll Sci & Technol, Blackett Lab, London SW7 2BW, England. CNRS, Ctr Etud Spatiale Rayonnements, F-31028 Toulouse, France. RP Eastwood, JP (reprint author), NASA, Goddard Space Flight Ctr, Geospace Phys Branch, Lab Solar & Space Phys, Code 612-3, Greenbelt, MD 20771 USA. EM jonathan.p.eastwood.1@gsfc.nasa.gov NR 52 TC 22 Z9 22 U1 0 U2 0 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 NOV 26 PY 2005 VL 110 IS A11 AR A11219 DI 10.1029/2004JA010617 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 988WY UT WOS:000233633400001 ER PT J AU Eastwood, JP Balogh, A Lucek, EA Mazelle, C Dandouras, I AF Eastwood, JP Balogh, A Lucek, EA Mazelle, C Dandouras, I TI Quasi-monochromatic ULF foreshock waves as observed by the four-spacecraft Cluster mission: 2. Oblique propagation SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID EARTHS BOW SHOCK; ION-BEAM INSTABILITIES; LOW-FREQUENCY WAVES; PARTICLE INTERACTION UPSTREAM; MAGNETOSONIC WAVES; PARALLEL SHOCKS; DIFFUSE IONS; SOLAR-WIND; 2-DIMENSIONAL SIMULATIONS; TERRESTRIAL FORESHOCK AB [1] This paper presents the results of a statistical investigation into the nature of oblique wave propagation in the foreshock. Observations have shown that foreshock ULF waves tend to propagate obliquely to the background magnetic field. This is in contrast to theoretical work, which predicts that the growth rate of the mechanism responsible for the waves is maximized for parallel propagation, at least in the linear regime in homogenous plasma. Here we use data from the Cluster mission to study in detail the oblique propagation of a particular class of foreshock ULF wave, the 30 s quasi-monochromatic wave. We find that these waves persistently propagate at oblique angles to the magnetic field. Over the whole data set, the average value of theta(kB) was found to be 21 +/- 14 degrees. Oblique propagation is observed even when the interplanetary magnetic field ( IMF) cone angle is small, such that the convective component of the solar wind velocity, v(E x B), is comparable to the wave speed. In this subset of the data, the mean value of theta(kB) was 12.9 +/- 7.1 degrees. In the subset of data for which the IMF cone angle exceeded 45 degrees, the mean value of theta(kB) was 19.5 +/- 10.7 degrees. When the angle between the IMF and the x geocentric solar ecliptic (GSE) direction (i.e., the solar wind vector) is large, the wave k vectors tend to be confined in the plane defined by the x GSE direction and the magnetic field and a systematic deflection is observed. The dependence of theta(kB) on v(E x B) is also studied. C1 NASA, Goddard Space Flight Ctr, Geospace Phys Branch, Lab Solar & Space Phys, Greenbelt, MD 20771 USA. Univ London Imperial Coll Sci & Technol, Blackett Lab, London SW7 2BW, England. CNRS, Ctr Etud Spatiale Rayonnements, F-31028 Toulouse, France. RP Eastwood, JP (reprint author), NASA, Goddard Space Flight Ctr, Geospace Phys Branch, Lab Solar & Space Phys, Code 612-3, Greenbelt, MD 20771 USA. EM jonathan.p.eastwood.1@gsfc.nasa.gov NR 60 TC 12 Z9 12 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 NOV 26 PY 2005 VL 110 IS A11 AR A11220 DI 10.1029/2004JA010618 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 988WY UT WOS:000233633400002 ER PT J AU Abbott, B Abbott, R Adhikari, R Agresti, J Ajith, P Allen, B Allen, J Amin, R Anderson, SB Anderson, WG Araya, M Armandula, H Ashley, M Aulbert, C Babak, S Balasubramanian, R Ballmer, S Barish, BC Barker, C Barker, D Barton, MA Bayer, K Belczynski, K Betzwieser, J Bhawal, B Bilenko, IA Billingsley, G Black, E Blackburn, K Blackburn, L Bland, B Bogue, L Bork, R Bose, S Brady, PR Braginsky, VB Brau, JE Brown, DA Buonanno, A Busby, D Butler, WE Cadonati, L Cagnoli, G Camp, JB Cannizzo, J Cannon, K Cardenas, L Carter, K Casey, MM Charlton, P Chatterji, S Chen, Y Chin, D Christensen, N Cokelaer, T Colacino, CN Coldwell, R Cook, D Corbitt, T Coyne, D Creighton, JDE Creighton, TD Dalrymple, J D'Ambrosio, E Danzmann, K Davies, G DeBra, D Dergachev, V Desai, S DeSalvo, R Dhurandar, S Diaz, M Di Credico, A Drever, RWP Dupuis, RJ Ehrens, P Etzel, T Evans, M Evans, T Fairhurst, S Finn, LS Franzen, KY Frey, RE Fritschel, P Frolov, VV Fyffe, M Ganezer, KS Garofoli, J Gholami, I Giaime, JA Goda, K Goggin, L Gonzalez, G Gray, C Gretarsson, AM Grimmett, D Grote, H Grunewald, S Guenther, M Gustafson, R Hamilton, WO Hanna, C Hanson, J Hardham, C Harry, G Heefner, J Heng, IS Hewitson, M Hindman, N Hoang, P Hough, J Hua, W Ito, M Itoh, Y Ivanov, A Johnson, B Johnson, WW Jones, DI Jones, G Jones, L Kalogera, V Katsavounidis, E Kawabe, K Kawamura, S Kells, W Khan, A Kim, C King, P Klimenko, S Koranda, S Kozak, D Krishnan, B Landry, M Lantz, B Lazzarini, A Lei, M Leonor, I Libbrecht, K Lindquist, P Liu, S Lormand, M Lubinski, M Luck, H Luna, M Machenschalk, B MacInnis, M Mageswaran, M Mailand, K Malec, M Mandic, V Marka, S Maros, E Mason, K Matone, L Mavalvala, N McCarthy, R McClelland, DE McHugh, M McNabb, JWC Melissinos, A Mendell, G Mercer, RA Meshkov, S Messaritaki, E Messenger, C Mikhailov, E Mitra, S Mitrofanov, VP Mitselmakher, G Mittleman, R Miyakawa, O Mohanty, S Moreno, G Mossavi, K Mueller, G Mukherjee, S Myers, E Myers, J Nash, T Nocera, F Noel, JS O'Reilly, B O'Shaughnessy, R Ottaway, DJ Overmier, H Owen, BJ Pan, Y Papa, MA Parameshwaraiah, V Parameswariah, C Pedraza, M Penn, S Pitkin, M Prix, R Quetschke, V Raab, F Radkins, H Rahkola, R Rakhmanov, M Rawlins, K Ray-Majumder, S Re, V Regimbau, T Reitze, DH Riesen, R Riles, K Rivera, B Robertson, DI Robertson, NA Robinson, C Roddy, S Rodriguez, A Rollins, J Romano, JD Romie, J Rowan, S Rudiger, A Ruet, L Russell, P Ryan, K Sandberg, V Sanders, GH Sannibale, V Sarin, P Sathyaprakash, BS Saulson, PR Savage, R Sazonov, A Schilling, R Schofield, R Schutz, BF Schwinberg, P Scott, SM Seader, SE Searle, AC Sears, B Sellers, D Sengupta, AS Shawhan, P Shoemaker, DH Sibley, A Siemens, X Sigg, D Sintes, AM Smith, J Smith, MR Spjeld, O Strain, KA Strom, DM Stuver, A Summerscales, T Sung, M Sutton, PJ Tanner, DB Taylor, R Thorne, KA Thorne, KS Tokmakov, KV Torres, C Torrie, C Traylor, G Tyler, W Ugolini, D Ungarelli, C Vallisneri, M van Putten, M Vass, S Vecchio, A Veitch, J Vorvick, C Vyachanin, SP Wallace, L Ward, H Ward, R Watts, K Webber, D Weiland, U Weinstein, A Weiss, R Wen, S Wette, K Whelan, JT Whitcomb, SE Whiting, BF Wiley, S Wilkinson, C Willems, PA Willke, B Wilson, A Winkler, W Wise, S Wiseman, AG Woan, G Woods, D Wooley, R Worden, J Yakushin, I Yamamoto, H Yoshida, S Zanolin, M Zhang, L Zotov, N Zucker, M Zweizig, J AF Abbott, B Abbott, R Adhikari, R Agresti, J Ajith, P Allen, B Allen, J Amin, R Anderson, SB Anderson, WG Araya, M Armandula, H Ashley, M Aulbert, C Babak, S Balasubramanian, R Ballmer, S Barish, BC Barker, C Barker, D Barton, MA Bayer, K Belczynski, K Betzwieser, J Bhawal, B Bilenko, IA Billingsley, G Black, E Blackburn, K Blackburn, L Bland, B Bogue, L Bork, R Bose, S Brady, PR Braginsky, VB Brau, JE Brown, DA Buonanno, A Busby, D Butler, WE Cadonati, L Cagnoli, G Camp, JB Cannizzo, J Cannon, K Cardenas, L Carter, K Casey, MM Charlton, P Chatterji, S Chen, Y Chin, D Christensen, N Cokelaer, T Colacino, CN Coldwell, R Cook, D Corbitt, T Coyne, D Creighton, JDE Creighton, TD Dalrymple, J D'Ambrosio, E Danzmann, K Davies, G DeBra, D Dergachev, V Desai, S DeSalvo, R Dhurandar, S Diaz, M Di Credico, A Drever, RWP Dupuis, RJ Ehrens, P Etzel, T Evans, M Evans, T Fairhurst, S Finn, LS Franzen, KY Frey, RE Fritschel, P Frolov, VV Fyffe, M Ganezer, KS Garofoli, J Gholami, I Giaime, JA Goda, K Goggin, L Gonzalez, G Gray, C Gretarsson, AM Grimmett, D Grote, H Grunewald, S Guenther, M Gustafson, R Hamilton, WO Hanna, C Hanson, J Hardham, C Harry, G Heefner, J Heng, IS Hewitson, M Hindman, N Hoang, P Hough, J Hua, W Ito, M Itoh, Y Ivanov, A Johnson, B Johnson, WW Jones, DI Jones, G Jones, L Kalogera, V Katsavounidis, E Kawabe, K Kawamura, S Kells, W Khan, A Kim, C King, P Klimenko, S Koranda, S Kozak, D Krishnan, B Landry, M Lantz, B Lazzarini, A Lei, M Leonor, I Libbrecht, K Lindquist, P Liu, S Lormand, M Lubinski, M Luck, H Luna, M Machenschalk, B MacInnis, M Mageswaran, M Mailand, K Malec, M Mandic, V Marka, S Maros, E Mason, K Matone, L Mavalvala, N McCarthy, R McClelland, DE McHugh, M McNabb, JWC Melissinos, A Mendell, G Mercer, RA Meshkov, S Messaritaki, E Messenger, C Mikhailov, E Mitra, S Mitrofanov, VP Mitselmakher, G Mittleman, R Miyakawa, O Mohanty, S Moreno, G Mossavi, K Mueller, G Mukherjee, S Myers, E Myers, J Nash, T Nocera, F Noel, JS O'Reilly, B O'Shaughnessy, R Ottaway, DJ Overmier, H Owen, BJ Pan, Y Papa, MA Parameshwaraiah, V Parameswariah, C Pedraza, M Penn, S Pitkin, M Prix, R Quetschke, V Raab, F Radkins, H Rahkola, R Rakhmanov, M Rawlins, K Ray-Majumder, S Re, V Regimbau, T Reitze, DH Riesen, R Riles, K Rivera, B Robertson, DI Robertson, NA Robinson, C Roddy, S Rodriguez, A Rollins, J Romano, JD Romie, J Rowan, S Rudiger, A Ruet, L Russell, P Ryan, K Sandberg, V Sanders, GH Sannibale, V Sarin, P Sathyaprakash, BS Saulson, PR Savage, R Sazonov, A Schilling, R Schofield, R Schutz, BF Schwinberg, P Scott, SM Seader, SE Searle, AC Sears, B Sellers, D Sengupta, AS Shawhan, P Shoemaker, DH Sibley, A Siemens, X Sigg, D Sintes, AM Smith, J Smith, MR Spjeld, O Strain, KA Strom, DM Stuver, A Summerscales, T Sung, M Sutton, PJ Tanner, DB Taylor, R Thorne, KA Thorne, KS Tokmakov, KV Torres, C Torrie, C Traylor, G Tyler, W Ugolini, D Ungarelli, C Vallisneri, M van Putten, M Vass, S Vecchio, A Veitch, J Vorvick, C Vyachanin, SP Wallace, L Ward, H Ward, R Watts, K Webber, D Weiland, U Weinstein, A Weiss, R Wen, S Wette, K Whelan, JT Whitcomb, SE Whiting, BF Wiley, S Wilkinson, C Willems, PA Willke, B Wilson, A Winkler, W Wise, S Wiseman, AG Woan, G Woods, D Wooley, R Worden, J Yakushin, I Yamamoto, H Yoshida, S Zanolin, M Zhang, L Zotov, N Zucker, M Zweizig, J CA LIGO Sci Collaboration TI Upper limits on a stochastic background of gravitational waves SO PHYSICAL REVIEW LETTERS LA English DT Article ID LIGO AB The Laser Interferometer Gravitational-Wave Observatory has performed a third science run with much improved sensitivities of all three interferometers. We present an analysis of approximately 200 hours of data acquired during this run, used to search for a stochastic background of gravitational radiation. We place upper bounds on the energy density stored as gravitational radiation for three different spectral power laws. For the flat spectrum, our limit of Omega(0)< 8.4x10(-4) in the 69-156 Hz band is similar to 10(5) times lower than the previous result in this frequency range. C1 CALTECH, LIGO, Pasadena, CA 91125 USA. Albert Einstein Inst, Max Planck Inst Gravitat Phys, D-14476 Golm, Germany. Albert Einstein Inst, Max Planck Inst Gravitat Phys, D-30167 Hannover, Germany. Australian Natl Univ, Canberra, ACT 0200, Australia. CALTECH, Pasadena, CA 91125 USA. Calif State Univ Dominguez Hills, Carson, CA 90747 USA. CALTECH, CaRT, Pasadena, CA 91125 USA. Cardiff Univ, Cardiff CF2 3YB, Wales. Carleton Coll, Northfield, MN 55057 USA. Columbia Univ, New York, NY 10027 USA. Hobart & William Smith Coll, Geneva, NY 14456 USA. Inter Univ Ctr Astron & Astrophys, Pune 411007, Maharashtra, India. MIT, LIGO, Cambridge, MA 02139 USA. LIGO Hanford Observ, Richland, WA 99352 USA. LIGO Livingston Observ, Livingston, LA 70754 USA. Louisiana State Univ, Baton Rouge, LA 70803 USA. Louisiana Tech Univ, Ruston, LA 71272 USA. Loyola Univ, New Orleans, LA 70118 USA. Moscow MV Lomonosov State Univ, Moscow 119992, Russia. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Natl Astron Observ, Tokyo 1818588, Japan. Northwestern Univ, Evanston, IL 60208 USA. SE Louisiana Univ, Hammond, LA 70402 USA. Stanford Univ, Stanford, CA 94305 USA. Syracuse Univ, Syracuse, NY 13244 USA. Penn State Univ, University Pk, PA 16802 USA. Univ Texas, Brownsville, TX 78520 USA. Tesas Southmost Coll, Brownsville, TX 78520 USA. Trinity Univ, San Antonio, TX 78212 USA. Univ Hannover, D-30167 Hannover, Germany. Univ Illes Balears, E-07122 Palma de Mallorca, Spain. Univ Birmingham, Birmingham B15 2TT, W Midlands, England. Univ Florida, Gainesville, FL 32611 USA. Univ Glasgow, Glasgow G12 8QQ, Lanark, Scotland. Univ Michigan, Ann Arbor, MI 48109 USA. Univ Oregon, Eugene, OR 97403 USA. Univ Rochester, Rochester, NY 14627 USA. Univ Wisconsin, Milwaukee, WI 53201 USA. Vassar Coll, Poughkeepsie, NY 12604 USA. Washington State Univ, Pullman, WA 99164 USA. RP Abbott, B (reprint author), CALTECH, LIGO, Pasadena, CA 91125 USA. RI McClelland, David/E-6765-2010; 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; Kawabe, Keita/G-9840-2011; Finn, Lee Samuel/A-3452-2009; Agresti, Juri/G-8168-2012; Mitrofanov, Valery/D-8501-2012; Bilenko, Igor/D-5172-2012; Ward, Robert/I-8032-2014; Allen, Bruce/K-2327-2012; Chen, Yanbei/A-2604-2013; Barker, David/A-5671-2013; Pitkin, Matthew/I-3802-2013; Liu, Sheng/K-2815-2013; Vyatchanin, Sergey/J-2238-2012; van Putten, Maurice/F-5237-2011; Vecchio, Alberto/F-8310-2015; Ottaway, David/J-5908-2015; Messaritaki, Eirini/D-7393-2016; Sigg, Daniel/I-4308-2015; Frey, Raymond/E-2830-2016; OI McClelland, David/0000-0001-6210-5842; Strain, Kenneth/0000-0002-2066-5355; Lueck, Harald/0000-0001-9350-4846; Finn, Lee Samuel/0000-0002-3937-0688; Agresti, Juri/0000-0001-6119-2470; Cokelaer, Thomas/0000-0001-6286-1138; Ward, Robert/0000-0001-5503-5241; Whelan, John/0000-0001-5710-6576; Zweizig, John/0000-0002-1521-3397; O'Shaughnessy, Richard/0000-0001-5832-8517; Fairhurst, Stephen/0000-0001-8480-1961; Allen, Bruce/0000-0003-4285-6256; Pitkin, Matthew/0000-0003-4548-526X; Vecchio, Alberto/0000-0002-6254-1617; Sigg, Daniel/0000-0003-4606-6526; Frey, Raymond/0000-0003-0341-2636; Aulbert, Carsten/0000-0002-1481-8319; Veitch, John/0000-0002-6508-0713; Papa, M.Alessandra/0000-0002-1007-5298 NR 14 TC 60 Z9 60 U1 1 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD NOV 25 PY 2005 VL 95 IS 22 AR 221101 DI 10.1103/PhysRevLett.95.221101 PG 6 WC Physics, Multidisciplinary SC Physics GA 986OB UT WOS:000233458500007 PM 16384203 ER PT J AU Mehta, VM DeCandis, AJ Mehta, AV AF Mehta, VM DeCandis, AJ Mehta, AV TI Remote-sensing-based estimates of the fundamental global water cycle: Annual cycle SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ATMOSPHERIC ENERGY TRANSPORTS; LATENT-HEAT FLUXES; HYDROLOGICAL CYCLE; TURBULENT FLUXES; SATELLITE RETRIEVALS; SURFACE; PRECIPITATION; PROJECT; SSM/I; RAINFALL AB [1] The average annual cycle of the atmospheric branch of the fundamental global water cycle ( FGWC) was studied with remote-sensing-based precipitation estimates from the Global Precipitation Climatology Project (GPCP; blended microwave-infrared-rain gauge) Version 2 and the Goddard Profiling algorithm (GPROF; passive microwave) Version 6 data sets and overocean evaporation estimates from the Goddard Satellite Surface Turbulent Fluxes Version 2 ( passive microwave) data set from 1988 to 2000. Overland evaporation was estimated from the remote-sensing-based precipitation estimates combined with a global evaporation minus precipitation (EmP) data set produced by the Climate Analysis Section of the National Center for Atmospheric Research. Results show that 75% to 85% of the total global evaporation and approximately 70% of the total global precipitation occur over the oceans in each season. In the GPCP-based FGWC estimate, there is a remarkable balance in the interhemispheric import-export of atmospheric moisture in December-January-February and June-July-August. The dominant cross-equatorial atmospheric moisture transports in the atmospheric branch of the FGWC supply a significant amount of moisture to precipitation regions and are from the Northern Hemisphere to the Southern Hemisphere in December-January-February and the Southern Hemisphere to the Northern Hemisphere in June-July-August, with approximately 3 x 10(6) m(3) s(-1) net annual transport from the Southern Hemisphere to the Northern Hemisphere in the GPCP-based FGWC estimate. In the GPROF-based FGWC estimate, there are substantial imbalances in interhemispheric moisture transports that may be attributable to missing data over snow- or ice-covered surfaces, inadequate diurnal sampling, and uncertainties in precipitation estimates especially over land. A quantitative evaluation of these results and comparisons with previous FGWC estimates is not possible without quantitative error estimates on precipitation, evaporation, and EmP estimates. These results show that evaporation, precipitation, and atmospheric moisture transport over the oceans play a very important role in the FGWC and that they should be a significant component in the Global Energy and Water Cycle Experiment and other national and international research programs on the global water cycle. C1 Ctr Res Changing Earth Syst, Columbia, MD 21044 USA. Univ Maryland Baltimore Cty, Joint Ctr Earth Syst Technol, Baltimore, MD 21228 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Mehta, VM (reprint author), Ctr Res Changing Earth Syst, 10211 Wincopin Circle,Suite 240, Columbia, MD 21044 USA. EM vikram@crces.org; decandis@crces.org; amita@radar.gsfc.nasa.gov NR 34 TC 7 Z9 7 U1 1 U2 3 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 NOV 24 PY 2005 VL 110 IS D22 AR D22103 DI 10.1029/2004JD005672 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 988WK UT WOS:000233632000001 ER PT J AU Eriksson, S Baker, JBH Petrinec, SM Wang, H Rich, FJ Kuznetsova, M Dunlop, MW Reme, H Greenwald, RA Frey, HU Luhr, H Ergun, RE Balogh, A Carlson, CW AF Eriksson, S Baker, JBH Petrinec, SM Wang, H Rich, FJ Kuznetsova, M Dunlop, MW Reme, H Greenwald, RA Frey, HU Luhr, H Ergun, RE Balogh, A Carlson, CW TI On the generation of enhanced sunward convection and transpolar aurora in the high-latitude ionosphere by magnetic merging SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID FIELD-ALIGNED CURRENTS; POLAR-CAP ARCS; SMALL-SCALE IRREGULARITIES; LOBE CELL CONVECTION; NORTHWARD IMF; THETA-AURORA; PLASMA SHEET; PARTICLE-PRECIPITATION; HARANG DISCONTINUITY; DISTANT MAGNETOTAIL AB [1] The IMAGE Wideband Imaging Camera (WIC) instrument observed the duskside development of an oval-aligned transpolar auroral arc (TPA) in the Northern Hemisphere (NH) on 16 December 2001 during strong IMF \B\ similar to 18 nT and a generally steady similar to 56 degrees clock angle ( positive IMF B-y and B-z). Observational evidence suggests that the dayside part of the duskside TPA formed due to quasi-continuous merging between the IMF and the lobe magnetic field tailward of the cusp while the nightside part is associated with the Harang discontinuity. The low-altitude CHAMP satellite confirms an upward northward IMF B-z (NBZ) field-aligned current (FAC) over the dayside TPA while associating a downward NBZ current with the region of diminished WIC emissions in between the auroral oval and the TPA. DMSP F14 suggests that the dayside region of the downward NBZ current coincides with precipitating magnetosheath-like ions of reversed energy-latitude dispersion consistent with high-latitude reconnection. SuperDARN observes enhanced ionospheric sunward flows generally centered between the oppositely directed NBZ currents. We associate these flows with a clockwise lobe convection vortex and the dayside part of the TPA. The nightside TPA, however, is related to stagnant or antisunward flow and the upward FAC region of the Harang discontinuity. Cluster observations confirm the simultaneous presence of rotational discontinuities across the duskside magnetopause with changes in the magnetosheath plasma velocity that indicate an active merging region poleward of Cluster. A global MHD simulation generates sunward flow between a pair of opposite FACs on either side of a lobe reconnection site near (X, Y, Z)(GSM) = (-4.7, 5.4, 10.2) R-E thus conforming with Cluster and SuperDARN expectations. The sense of these FACs agrees with the low-altitude NBZ observations. C1 Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80303 USA. Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. Lockheed Martin Adv Technol Ctr, Palo Alto, CA 94304 USA. Geoforschungszentrum Potsdam, D-14473 Potsdam, Germany. USAF, Res Lab, Hanscom AFB, MA 01731 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Rutherford Appleton Lab, Div Space Sci, Chilton OX11 0QX, England. Ctr Etud Spatiale Rayonnements, F-31029 Toulouse, France. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2BZ, England. RP Univ Colorado, Atmospher & Space Phys Lab, 1234 Innovat Dr, Boulder, CO 80303 USA. EM eriksson@lasp.colorado.edu RI Kuznetsova, Maria/F-6840-2012; OI Eriksson, Stefan/0000-0002-5619-1577; Greenwald, Raymond/0000-0002-7421-5536 NR 91 TC 23 Z9 23 U1 0 U2 3 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 NOV 23 PY 2005 VL 110 IS A11 AR A11218 DI 10.1029/2005JA011149 PG 27 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 988WX UT WOS:000233633300001 ER PT J AU Kleidman, RG O'Neill, NT Remer, LA Kaufman, YJ Eck, TF Tanre, D Dubovik, O Holben, BN AF Kleidman, RG O'Neill, NT Remer, LA Kaufman, YJ Eck, TF Tanre, D Dubovik, O Holben, BN TI Comparison of moderate resolution Imaging spectroradiometer (MODIS) and aerosol robotic network (AERONET) remote-sensing retrievals of aerosol fine mode fraction over ocean SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SKY RADIANCE MEASUREMENTS; OPTICAL-PROPERTIES; SPECTRAL RADIANCES; SIZE DISTRIBUTION; DUST AEROSOL; SCATTERING; ALGORITHM; SYSTEM; DEPTH; LAND AB [1] Aerosol particle size is one of the fundamental quantities needed to determine the role of aerosols in forcing climate, modifying the hydrological cycle, and affecting human health and to separate natural from man-made aerosol components. Aerosol size information can be retrieved from remote-sensing instruments including satellite sensors such as Moderate Resolution Imaging Spectroradiometer ( MODIS) and ground-based radiometers such as Aerosol Robotic Network (AERONET). Both satellite and ground-based instruments measure the total column ambient aerosol characteristics. Aerosol size can be characterized by a variety of parameters. Here we compare remote-sensing retrievals of aerosol fine mode fraction over ocean. AERONET retrieves fine mode fraction using two methods: the Dubovik inversion of sky radiances and the O'Neill inversion of spectral Sun measurements. Relative to the Dubovik inversion of AERONET sky measurements, MODIS slightly overestimates fine fraction for dust-dominated aerosols and underestimates in smoke-and pollution-dominated aerosol conditions. Both MODIS and the Dubovik inversion overestimate fine fraction for dust aerosols by 0.1 - 0.2 relative to the O'Neill method of inverting AERONET aerosol optical depth spectra. Differences between the two AERONET methods are principally the result of the different definitions of fine and coarse mode employed in their computational methodologies. These two methods should come into better agreement as a dynamic radius cutoff for fine and coarse mode is implemented for the Dubovik inversion. MODIS overestimation in dust-dominated aerosol conditions should decrease significantly with the inclusion of a nonspherical model. C1 Sci Syst & Applicat Inc, Greenbelt, MD 20770 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Sherbrooke, Ctr Applicat & Rech Teledetect, Sherbrooke, PQ J1K 2R1, Canada. Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. Univ Sci & Technol Lille, CNRS, Opt Atmospher Lab, F-59655 Villeneuve Dascq, France. RP Sci Syst & Applicat Inc, Greenbelt, MD 20770 USA. EM kleidman@climate.gsfc.nasa.gov RI Dubovik, Oleg/A-8235-2009; ECK, THOMAS/D-7407-2012 OI Dubovik, Oleg/0000-0003-3482-6460; NR 23 TC 62 Z9 64 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 NOV 22 PY 2005 VL 110 IS D22 AR D22205 DI 10.1029/2005JD005760 PG 6 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 988WJ UT WOS:000233631900001 ER PT J AU Page, KL Reeves, JN O'Brien, PT Turner, MJL AF Page, KL Reeves, JN O'Brien, PT Turner, MJL TI XMM-Newton spectroscopy of high-redshift quasars SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE galaxies : active; quasars : general; X-rays : galaxies ID X-RAY-SPECTRA; ACTIVE GALACTIC NUCLEI; LYMAN-ALPHA SYSTEMS; BAND ENERGY-DISTRIBUTION; ROSAT DETECTED QUASARS; RADIO-QUIET QUASARS; SKY SURVEY; STATISTICAL-METHODS; ABSORPTION SYSTEMS; ASTRONOMICAL DATA AB XMM-Newton observations of 29 high-redshift (z > 2) quasars, including seven radio-quiet, 16 radio-loud and six broad absorption line (BAL) objects, are presented; due to the high redshifts, the rest-frame energy bands extend up to similar to 30-70 keV. Over 2-10 keV, the quasars can be well fitted in each case by a simple power law, with no strong evidence for iron emission lines. The lack of iron lines is in agreement both with dilution by the radio jet emission ( for the radio-loud quasars) and the X-ray Baldwin effect. No Compton reflection humps at higher energies (i.e. above 10 keV in the rest frame) are detected either. Over the broad-band (0.3-10 keV), approximately half ( nine out of 16) of the radio-loud quasars are intrinsically absorbed, with the values of N-H generally being 1 x 1022 to 2 x 1022 cm(-2) in the rest frames of the objects. None of the seven radio-quiet objects shows excess absorption, while four of the six BAL quasars are absorbed. The radio-loud quasars have flatter continuum slopes than their radio-quiet counterparts (Gamma(RL) similar to 1.55; similar to Gamma(RL) similar to 1.98 over 2-10 keV), while, after modelling the absorption, the underlying photon index for the six BAL quasars is formally consistent with the non-BAL radio-quiet objects. C1 Univ Leicester, Dept Phys & Astron, X Ray & Observ Astron Grp, Leicester LE1 7RH, Leics, England. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. RP Univ Leicester, Dept Phys & Astron, X Ray & Observ Astron Grp, Leicester LE1 7RH, Leics, England. EM kpa@star.le.ac.uk NR 95 TC 84 Z9 84 U1 1 U2 1 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 NOV 21 PY 2005 VL 364 IS 1 BP 195 EP 207 DI 10.1111/j.1365-2966.2005.09550.x PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 983CM UT WOS:000233208700040 ER PT J AU Ren, DQ Serabyn, E AF Ren, DQ Serabyn, E TI Symmetric nulling coronagraph based on a rotational shearing interferometer SO APPLIED OPTICS LA English DT Article ID EXTRASOLAR PLANETS; REMNANT SPECKLES; PHASE-MASK; APODIZATION; TELESCOPES AB We describe a fully symmetric nulling coronagraph for single-aperture telescopes that is based on a rotational shearing interferometer (RSI) and that is intended for the imaging of faint companions to nearby bright stars. In the proposed layout, all asymmetries inherent in previous single-aperture RSI-based nulling coronagraphs have been eliminated, and the bright and dark outputs are both accessible. As a result, deep, broadband, dual-polarization rejection of on-axis starlight should be possible with this system. (c) 2005 Optical Society of America. C1 New Jersey Inst Technol, Dept Phys, Newark, NJ 07102 USA. CALTECH, Jet Propuls Lab, Pasadena, CA 91109 USA. RP Ren, DQ (reprint author), New Jersey Inst Technol, Dept Phys, Newark, NJ 07102 USA. EM deqing.ren@njit.edu; eserabyn@s383jpl.nasa.gov NR 33 TC 13 Z9 13 U1 0 U2 0 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 NOV 20 PY 2005 VL 44 IS 33 BP 7070 EP 7073 DI 10.1364/AO.44.007070 PG 4 WC Optics SC Optics GA 984ZD UT WOS:000233345000008 PM 16318176 ER PT J AU Sonnabend, G Wirtz, D Schieder, R AF Sonnabend, G Wirtz, D Schieder, R TI Evaluation of quantum-cascade lasers as local oscillators for infrared heterodyne spectroscopy SO APPLIED OPTICS LA English DT Article ID CO2 EMISSION; MU-M; LINEWIDTH AB We report experiments evaluating the feasibility of quantum-cascade lasers (QCLs) at mid-infrared wavelengths for use as local oscillators (LOs) in a heterodyne receiver. Performance tests with continuous-wave (cw) lasers around 9.6 and 9.2 tm were carried out investigating optical output power, laser linewidth, and tunability. A direct comparison with a CO2 gas laser LO is presented as well. The achieved system sensitivity in a heterodyne spectrometer of only a factor of 2 above the quantum limit together with the measured linewidth of less than 1.5 MHz shows that QCLs are suitable laser sources for heterodyne spectroscopy with sufficient output power to replace gas, lasers as LOs even in highsensitivity astronomical heterodyne receivers. In addition, our experiments show that the tunability of the lasers can be greatly enhanced by use of an external cavity. (c) 2005 Optical Society of America. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20770 USA. Univ Cologne, Inst Phys, D-50937 Cologne, Germany. RP Sonnabend, G (reprint author), NASA, Goddard Space Flight Ctr, Code 693, Greenbelt, MD 20770 USA. EM samstag@phl.uni-koehi.de NR 13 TC 14 Z9 14 U1 0 U2 2 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 NOV 20 PY 2005 VL 44 IS 33 BP 7170 EP 7172 DI 10.1364/AO.44.007170 PG 3 WC Optics SC Optics GA 984ZD UT WOS:000233345000021 PM 16318188 ER PT J AU Boone, CD Nassar, R Walker, KA Rochon, Y McLeod, SD Rinsland, CP Bernath, PF AF Boone, CD Nassar, R Walker, KA Rochon, Y McLeod, SD Rinsland, CP Bernath, PF TI Retrievals for the atmospheric chemistry experiment Fourier-transform spectrometer SO APPLIED OPTICS LA English DT Article ID CANADIAN METEOROLOGICAL CENTER; PRESSURE-TEMPERATURE PROFILES; DATA ASSIMILATION SYSTEM; MULTISCALE GEM MODEL; LIMB-EMISSION; PART II; CO2; IMPLEMENTATION; ABUNDANCES; ALGORITHM AB SCISAT-1, also known as the Atmospheric Chemistry Experiment, is a satellite mission for remote sensing of the Earth's atmosphere, launched on 12 August 2003. The primary instrument on the satellite is a 0.02 cm(-1) resolution Fourier-transform spectrometer operating in the mid-IR (750-4400 cm(-1)). We describe the approach developed for the retrieval of atmospheric temperature and pressure from the troposphere to the lower thermosphere as well as the strategy for the retrievals of volume-mixing ratio profiles of atmospheric species. (c) 2005 Optical Society of America. C1 Univ Waterloo, Dept Chem, Waterloo, ON N2L 3G1, Canada. NASA, Langley Res Ctr, Div Atmospher Sci, Hampton, VA 23681 USA. Environm Canada, Meteorol Serv Canada, Toronto, ON M3H 5T4, Canada. RP Univ Waterloo, Dept Chem, 200 Univ Ave W, Waterloo, ON N2L 3G1, Canada. EM cboone@acebox.uwaterloo.ca RI Bernath, Peter/B-6567-2012; OI Bernath, Peter/0000-0002-1255-396X; Nassar, Ray/0000-0001-6282-1611 NR 40 TC 217 Z9 217 U1 0 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 NOV 20 PY 2005 VL 44 IS 33 BP 7218 EP 7231 DI 10.1364/AO.44.007218 PG 14 WC Optics SC Optics GA 984ZD UT WOS:000233345000028 PM 16318195 ER PT J AU Yan, HJ Dickinson, M Stern, D Eisenhardt, PRM Chary, RR Giavalisco, M Ferguson, HC Casertano, S Conselice, CJ Papovich, C Reach, WT Grogin, N Moustakas, LA Ouchi, M AF Yan, HJ Dickinson, M Stern, D Eisenhardt, PRM Chary, RR Giavalisco, M Ferguson, HC Casertano, S Conselice, CJ Papovich, C Reach, WT Grogin, N Moustakas, LA Ouchi, M TI Rest-frame ultraviolet-to-optical properties of galaxies at z approximate to 6 and z approximate to 5 in the Hubble Ultra Deep Field: From Hubble to Spitzer SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmology : observations; galaxies : evolution; galaxies : luminosity function, mass function; infrared : galaxies ID HIGH-REDSHIFT GALAXIES; STAR-FORMING GALAXIES; LYMAN BREAK GALAXIES; SPACE-TELESCOPE; STELLAR MASSES; LUMINOSITY FUNCTION; DATA REDUCTION; EVOLUTION; UNIVERSE; CAMERA AB We use data from the first epoch of observations with the Infrared Array Camera ( IRAC) on the Spitzer Space Telescope for the Great Observatories Origins Deep Survey ( GOODS) to detect and study a collection of Lyman break galaxies at z approximate to 6 5 in the Hubble Ultra Deep Field ( HUDF), six of which have spectroscopic confirmation. At these redshifts, IRAC samples rest-frame optical light in the range 0.5 - 0.8 mu m, where the effects of dust extinction are smaller and the sensitivity to light from evolved stars is greater than at shorter, rest- frame ultraviolet wavelengths observable from the ground or with the Hubble Space Telescope. As such, it provides useful constraints on the ages and masses of these galaxies' stellar populations. We find that the spectral energy distributions for many of these galaxies are best fitted by models of stellar populations with masses of a few times 10(10) M-circle dot and with ages of a few hundred million years, values quite similar to those derived for typical Lyman break galaxies at z approximate to 3. When the universe was only 1 Gyr old, some galaxies had already formed a mass of stars approaching that of the present-day Milky Way, and they started forming those stars at z > 7 and in some cases much earlier. We find that the lower limits to the space density for galaxies in this mass range are consistent with predictions from recent hydrodynamic simulations of structure formation in a Lambda CDM universe. All objects in our samples are consistent with having solar metallicity, suggesting that they might have already been significantly polluted by metals and thus are not comprised of "first stars.'' The values for dust reddening derived from the model fitting are low or zero, and we find that some of the galaxies have rest- frame UV colors that are even bluer than those predicted by the stellar population models to which we compare them. These colors might be attributed to the presence of very massive stars (> 100 M-circle dot) or weaker intergalactic H I absorption than what is commonly assumed. C1 CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA. Natl Opt Astron Observ, Tucson, AZ 85719 USA. CALTECH, Jet Propuls Lab, Pasadena, CA 91109 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. CALTECH, Dept Astron, Pasadena, CA 91125 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. RP Yan, HJ (reprint author), CALTECH, Spitzer Sci Ctr, MS 220-6, Pasadena, CA 91125 USA. EM yhj@ipac.caltech.edu RI Ouchi, Masami/A-4490-2011; Conselice, Christopher/B-4348-2013; OI Reach, William/0000-0001-8362-4094 NR 41 TC 115 Z9 115 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 NOV 20 PY 2005 VL 634 IS 1 BP 109 EP 127 DI 10.1086/491695 PN 1 PG 19 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 985AF UT WOS:000233347800010 ER PT J AU Dwek, E Krennrich, F Arendt, RG AF Dwek, E Krennrich, F Arendt, RG TI Is there an imprint of primordial stars in the TeV gamma-ray spectrum of blazars? SO ASTROPHYSICAL JOURNAL LA English DT Article DE BL Lacertae objects : individual (Mrk 421, Mrk 501, H1426+428, PKS 2155-304); cosmology : theory; diffuse radiation; early universe; galaxies : active; gamma rays : observations; infrared : general; stars : formation ID EXTRAGALACTIC BACKGROUND LIGHT; PKS 2155-304; TENTATIVE DETECTION; H1426+428; MICRONS; DIRBE; MARKARIAN-421; PKS-2155-304; DETECTIONS; TELESCOPE AB The 1-5 mu m diffuse sky emission from which local foreground emission from the solar system and the Galaxy have been subtracted exceeds the brightness that can be attributed to normal star-forming galaxies. The nature of this excess near-infrared background light (NIRBL) is controversial. On the one hand, its sharp rise at similar to 1.25 mu m has been interpreted as a distinct spectral feature created by the redshifted emission from primordial (Population III) stars that have formed at redshifts greater than or similar to 8. On the other hand, the measured NIRBL spectrum is almost identical to that of the zodiacal cloud, raising the possibility that it is of local origin. Blazars can, in principle, offer a simple test for the nature and origin of the NIRBL. Very high energy gamma-ray photons emitted by these objects are attenuated en route to Earth by gamma-gamma interactions with the extragalactic background light (EBL). Assuming that the NIRBL is of extragalactic origin, its distinct spectral feature should give rise to a corresponding absorption feature in the observed gamma-ray spectra of these sources. This paper examines whether the extragalactic nature of the NIRBL can be determined from the analysis of the gamma-ray spectra of blazars. We calculate the gamma-ray opacity toward two blazars H1426+428 and PKS 2155-304 located at redshifts of z approximate to 0.13 for several EBL scenarios with and without the alleged spectral signature of the Population III stars. We show that if the NIRBL is extragalactic, it may be very difficult to reproduce the absorption-corrected spectrum of PKS 2155-304 with a synchrotron self-Compton (SSC) model that is also consistent with the X-ray and EGRET gamma-ray data. This, and other arguments presented in this paper, cast serious doubts on the possibility that the NIRBL represents the spectral imprint of the first generation of stellar objects on the EBL. C1 NASA, Goddard Space Flight Ctr, Observ Cosmol Lab, Sci Syst & Applicat Inc, Greenbelt, MD 20771 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP Dwek, E (reprint author), NASA, Goddard Space Flight Ctr, Observ Cosmol Lab, Sci Syst & Applicat Inc, Code 665, Greenbelt, MD 20771 USA. EM eli.dwek@nasa.gov NR 33 TC 22 Z9 22 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 NOV 20 PY 2005 VL 634 IS 1 BP 155 EP 160 DI 10.1086/462400 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 985AF UT WOS:000233347800015 ER PT J AU Heckman, TM Ptak, A Hornschemeier, A Kauffmann, G AF Heckman, TM Ptak, A Hornschemeier, A Kauffmann, G TI The relationship of hard X-ray and optical line emission in low-redshift active galactic nuclei SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; galaxies : Seyfert; quasars : general; X-rays : galaxies ID DIGITAL-SKY-SURVEY; SEYFERT 2 GALAXIES; STAR-FORMING GALAXIES; RADIO-LOUD; LUMINOSITY FUNCTION; MULTIWAVELENGTH OBSERVATIONS; HELLAS2XMM SURVEY; UNIFIED MODELS; TORUS MODEL; CATALOG AB In this paper we assess the relationship of the population of active galactic nuclei (AGNs) selected by hard X-rays to the traditional population of AGNs with strong optical emission lines. First, we study the emission-line properties of a new hard-X-ray-selected sample of 47 local AGNs (classified optically as Type 1 and 2 AGNs). We find that the hard X-ray (3-20 keV) and [O III] lambda 5007 optical emission-line luminosities are well-correlated over a range of about 4 orders of magnitude in luminosity (mean luminosity ratio 2.15 dex with a standard deviation of sigma 0: 51 dex). Second, we study the hard X-ray properties of a sample of 55 local AGNs selected from the literature on the basis of the flux in the [O III] line. The correlation between the hard X-ray (2-10 keV) and [O III] luminosity for the Type 1 AGNs is consistent with what is seen in the hard-X-ray-selected sample. However, the Type 2 AGNs have a much larger range in the luminosity ratio, and many are very weak in hard X-rays (as expected for heavily absorbed AGNs). We then compare the hard X-ray (3-20 keV) and [O III] luminosity functions of AGNs in the local universe. These have similar faint-end slopes, with a luminosity ratio of 1.60 dex (0.55 dex smaller than the mean value for individual hard-X-ray-selected AGNs). We conclude that at low redshift, selection by narrow optical emission lines will recover most AGNs selected by hard X-rays (with the exception of BL Lac objects). However, selection by hard X-rays misses a significant fraction of the local AGN population with strong emission lines. C1 Johns Hopkins Univ, Ctr Astrophys Sci, Dept Phys & Astron, Baltimore, MD 21218 USA. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. Max Planck Inst Astrophys, D-85748 Garching, Germany. RP Heckman, TM (reprint author), Johns Hopkins Univ, Ctr Astrophys Sci, Dept Phys & Astron, Baltimore, MD 21218 USA. EM heckman@pha.jhu.edu RI Ptak, Andrew/D-3574-2012 NR 50 TC 149 Z9 150 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 NOV 20 PY 2005 VL 634 IS 1 BP 161 EP 168 DI 10.1086/491665 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 985AF UT WOS:000233347800016 ER PT J AU Scott, JE Kriss, GA Lee, JC Quijano, JK Brotherton, M Canizares, CR Green, RF Hutchings, J Kaiser, ME Marshall, H Oegerle, W Ogle, P Zheng, W AF Scott, JE Kriss, GA Lee, JC Quijano, JK Brotherton, M Canizares, CR Green, RF Hutchings, J Kaiser, ME Marshall, H Oegerle, W Ogle, P Zheng, W TI Intrinsic absorption in the spectrum of NGC 7469: Simultaneous Chandra, FUSE, and STIS observations SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; galaxies : individual ( NGC 7469); galaxies : Seyfert; quasars : absorption lines; ultraviolet : galaxies; X rays : galaxies ID ACTIVE GALACTIC NUCLEI; X-RAY SPECTROSCOPY; TELESCOPE IMAGING SPECTROGRAPH; HUBBLE-SPACE-TELESCOPE; BROAD-LINE REGION; SEYFERT-1 GALAXY NGC-7469; IONIZED-GAS; XMM-NEWTON; ECHELLE OBSERVATIONS; PHYSICAL CONDITIONS AB We present simultaneous X-ray, far-ultraviolet, and near-ultraviolet spectra of the Seyfert 1 galaxy NGC 7469 obtained with the Chandra X-Ray Observatory, the Far Ultraviolet Spectroscopic Explorer, and the Space Telescope Imaging Spectrograph on the Hubble Space Telescope. Previous nonsimultaneous observations of this galaxy found two distinct UV absorption components, at -560 and -1900 km s(-1), with the former as the likely counterpart of the X-ray absorber. We confirm these two absorption components in our new UV observations, in which we detect prominent O VI, Ly alpha, N V, and C IV absorption. In our Chandra spectrum we detect O VIII emission, but no significant O VIII or O VII absorption. We also detect a prominent Fe K alpha emission line in the Chandra spectrum, as well as absorption due to hydrogen-like and helium-like neon, magnesium, and silicon at velocities consistent with the -560 km s(-1) UV absorber. The FUSE and STIS data reveal that the H I and C IV column densities in this UV- and X-ray-absorbing component have increased over time, as the UV continuum flux decreased. We use measured H I, N V, C IV, and O VI column densities to model the photoionization state of both absorbers self-consistently. We confirm the general physical picture of the outflow in which the low-velocity component is a highly ionized, high-density absorber with a total column density of 10(20) cm(-2), located near the broad emission-line region, although due to measurable columns of N V and C IV, we assign it a somewhat smaller ionization parameter than found previously, U similar to 1. The high-velocity UV component is of lower density, log N = 18.6, and likely resides farther from the central engine, as we find its ionization parameter to be U = 0.08. C1 NASA, Goddard Space Flight Ctr, Observ Cosmol Lab, Greenbelt, MD 20771 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Johns Hopkins Univ, Dept Phys & Astron, Ctr Astrophys Sci, Baltimore, MD 21218 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Wyoming, Dept Phys & Astron, Laramie, WY 82071 USA. MIT, Dept Phys, Cambridge, MA 02139 USA. MIT, Ctr Space Res, Cambridge, MA 02139 USA. Kitt Peak Natl Observ, Natl Opt Astron Observ, Tucson, AZ 85726 USA. Natl Res Council Canada, Herzberg Inst Astrophys, Victoria, BC V9E 2E7, Canada. NASA, Goddard Space Flight Ctr, ExoPlanets & Stellar Astrophys Lab, Greenbelt, MD 20771 USA. Jet Propuls Lab, Pasadena, CA 91109 USA. RP Scott, JE (reprint author), NASA, Goddard Space Flight Ctr, Observ Cosmol Lab, Code 661, Greenbelt, MD 20771 USA. EM jscott@stis.gsfc.nasa.gov; gak@stsci.edu; jclee@cfa.harvard.edu; jkim@stsci.edu; mborther@uwyo.edu; crc@space.mit.edu; rgreen@noao.edu; john.hutchings@hia.nrc.ca; kaiser@pha.jhu.edu; hermanm@space.mit.edu; oegerle@uvo.gsfc.nasa.gov; pmo@sgra.jpl.nasa.gov; zheng@pha.jhu.edu RI Oegerle, William/C-9070-2012; Lee, Julia/G-2381-2015 OI Lee, Julia/0000-0002-7336-3588 NR 71 TC 23 Z9 23 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 NOV 20 PY 2005 VL 634 IS 1 BP 193 EP 209 DI 10.1086/496911 PN 1 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 985AF UT WOS:000233347800019 ER PT J AU Binns, WR Wiedenbeck, ME Arnould, M Cummings, AC George, JS Goriely, S Israel, MH Leske, RA Mewaldt, RA Meynet, G Scott, LM Stone, EC von Rosenvinge, TT AF Binns, WR Wiedenbeck, ME Arnould, M Cummings, AC George, JS Goriely, S Israel, MH Leske, RA Mewaldt, RA Meynet, G Scott, LM Stone, EC von Rosenvinge, TT TI Cosmic-ray neon, Wolf-Rayet stars, and the superbubble origin of galactic cosmic rays SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmic rays; galaxy : abundances; galaxy : stellar content; stars : Wolf-Rayet ID SOLAR ENERGETIC PARTICLES; ANOMALOUS ISOTOPIC COMPOSITION; PROTON-INDUCED REACTIONS; LIQUID-HYDROGEN TARGET; ISO-SWS SPECTROSCOPY; CROSS-SECTIONS; MASSIVE STARS; NOBLE-GASES; STELLAR EVOLUTION; ELEMENTS 6-LESS-THAN-OR-EQUAL-TO-Z-LESS-THAN-OR-EQUAL-TO-29 AB We report the abundances of neon isotopes in the Galactic cosmic rays (GCRs) using data from the Cosmic Ray Isotope Spectrometer (CRIS) aboard the Advanced Composition Explorer ( ACE). These abundances have been measured for seven energy intervals over the energy range of 84 <= E/M <= 273 MeV nucleon(-1). We have derived the (22)Ne/(20)Ne ratio at the cosmic-ray source using the measured (21)Ne, (19)F, and (17)O abundances as "tracers'' of secondary production of the neon isotopes. Using this approach, the (22)Ne/(20)Ne abundance ratio that we obtain for the cosmicray source is 0.387 +/- 0: 007(statistical) +/- 0.022(systematic). This corresponds to an enhancement by a factor of 5.3 +/- 0.3 over the (22)Ne/(20)Ne ratio in the solar wind. This cosmic-ray source (22)Ne/(20)Ne ratio is also significantly larger than that found in anomalous cosmic rays, solar energetic particles, most meteoritic samples of matter, and interplanetary dust particles. We compare our ACE CRIS data for neon and refractory isotope ratios, and data from other experiments, with recent results from two-component Wolf-Rayet (W-R) models. The three largest deviations of GCR isotope ratios from solar system ratios predicted by these models, (12)C/(16)O, (22)Ne/(20)Ne, and (58)Fe/(56)Fe, are indeed present in the GCRs. In fact, all of the isotope ratios that we have measured are consistent with a GCR source consisting of about 80% material with solar system composition and about 20% W-R material. Since W-R stars are evolutionary products of OB stars, and most OB stars exist in OB associations that form superbubbles, the good agreement of these data with W-R models suggests that superbubbles are the likely source of at least a substantial fraction of GCRs. C1 Washington Univ, Dept Phys, St Louis, MO 63130 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Libre Bruxelles, Inst Astron & Astrophys, Brussels, Belgium. CALTECH, Dept Phys, Pasadena, CA 91125 USA. Observ Geneva, CH-1290 Chavannes Des Bois, Switzerland. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Binns, WR (reprint author), Washington Univ, Dept Phys, St Louis, MO 63130 USA. EM wrb@wuphys.wustl.edu NR 96 TC 47 Z9 48 U1 0 U2 4 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 NOV 20 PY 2005 VL 634 IS 1 BP 351 EP 364 DI 10.1086/496959 PN 1 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 985AF UT WOS:000233347800030 ER PT J AU Thomas, BC Melott, AL Jackman, CH Laird, CM Medvedev, MV Stolarski, RS Gehrels, N Cannizzo, JK Hogan, DP Ejzak, LM AF Thomas, BC Melott, AL Jackman, CH Laird, CM Medvedev, MV Stolarski, RS Gehrels, N Cannizzo, JK Hogan, DP Ejzak, LM TI Gamma-ray bursts and the earth: Exploration of atmospheric, biological, climatic, and biogeochemical effects SO ASTROPHYSICAL JOURNAL LA English DT Article DE astrobiology; gamma rays : bursts ID ABSORPTION CROSS-SECTION; PARABOLIC METHOD PPM; SOLAR PROTON EVENTS; 2-DIMENSIONAL MODEL; LATE ORDOVICIAN; COSMIC-RAYS; OZONE DEPLETION; STRATOSPHERIC AIRCRAFT; ULTRAVIOLET-RADIATION; MIDDLE ATMOSPHERE AB Gamma-ray bursts (GRBs) are likely to have made a number of significant impacts on the Earth during the last billion years. The gamma radiation from a burst within a few kiloparsecs would quickly deplete much of the Earth's protective ozone layer, allowing an increase in solar UVB radiation reaching the surface. This radiation is harmful to life, damaging DNA and causing sunburn. In addition, NO2 produced in the atmosphere would cause a decrease in visible sunlight reaching the surface and could cause global cooling. Nitric acid rain could stress portions of the biosphere, but the increased nitrate deposition could be helpful to land plants. We have used a two-dimensional atmospheric model to investigate the effects on the Earth's atmosphere of GRBs delivering a range of fluences, at various latitudes, at the equinoxes and solstices, and at different times of day. We have estimated DNA damage levels caused by increased solar UVB radiation, reduction in solar visible light due to NO2 opacity, and deposition of nitrates through rainout of HNO3. For the "typical" nearest burst in the last billion years, we find globally averaged ozone depletion up to 38%. Localized depletion reaches as much as 74%. Significant global depletion (at least 10%) persists up to about 7 yr after the burst. Our results depend strongly on time of year and latitude over which the burst occurs. The impact scales with the total fluence of the GRB at the Earth but is insensitive to the time of day of the burst and its duration (1-1000 s). We find DNA damage of up to 16 times the normal annual global average, well above lethal levels for simple life forms such as phytoplankton. The greatest damage occurs at mid- to low latitudes. We find reductions in visible sunlight of a few percent, primarily in the polar regions. Nitrate deposition similar to or slightly greater than that currently caused by lightning is also observed, lasting several years. We discuss how these results support the hypothesis that the Late Ordovician mass extinction may have been initiated by a GRB. C1 Univ Kansas, Dept Phys & Astron, Lawrence, KS 66045 USA. NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. Haskell Indian Nat Univ, Lawrence, KS 66046 USA. NASA, Goddard Space Flight Ctr, Lab Astroparticle Phys, Greenbelt, MD 20771 USA. RP Thomas, BC (reprint author), Washburn Univ, Dept Phys & Astron, 1700 Coll,Stoffer Sci Hall, Topeka, KS 66621 USA. EM bthomas@ku.edu; melott@ku.edu; jackman@assess.gsfc.nasa.gov; claird@ku.edu; stolar@polska.gsfc.nasa.gov; gehrels@milkyway.gsfc.nasa.gov; cannizzo@milkyway.gsfc.nasa.gov; dphogan@ku.edu RI Gehrels, Neil/D-2971-2012; Stolarski, Richard/B-8499-2013; Jackman, Charles/D-4699-2012; OI Stolarski, Richard/0000-0001-8722-4012; Thomas, Brian/0000-0001-9091-0830 NR 76 TC 60 Z9 60 U1 6 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 NOV 20 PY 2005 VL 634 IS 1 BP 509 EP 533 DI 10.1086/496914 PN 1 PG 25 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 985AF UT WOS:000233347800045 ER PT J AU Watts, AL Strohmayer, TE Markwardt, CB AF Watts, AL Strohmayer, TE Markwardt, CB TI Analysis of variability in the burst oscillations of the accreting millisecond pulsar XTE J1814-338 SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : general; stars : individual (XTE J1814-338); stars : neutron; stars : rotation; X-rays : binaries; X-rays : bursts; X-rays : stars ID X-RAY-BURSTS; NEUTRON-STARS; DISK ACCRETION; LIGHT CURVES; R-MODES; EMISSION; BINARY; DISCOVERY; SURFACE; PHASE AB The accreting millisecond pulsar XTE J1814-338 exhibits oscillations at the known spin frequency during type I X-ray bursts. The properties of the burst oscillations reflect the nature of the thermal asymmetry on the stellar surface. We present an analysis of the variability of the burst oscillations of this source, focusing on three characteristics: fractional amplitude, harmonic content, and frequency. Fractional amplitude and harmonic content constrain the size, shape, and position of the emitting region, while variations in frequency indicate motion of the emitting region on the neutron star surface. We examine both long-term variability over the course of the outburst and short-term variability during the bursts. For most of the bursts, fractional amplitude is consistent with that of the accretion pulsations, implying a low degree of fuel spread. There is, however, a population of bursts whose fractional amplitudes are substantially lower, implying a higher degree of fuel spread, possibly forced by the explosive burning front of a precursor burst. For the first harmonic, substantial differences between the burst and accretion pulsations suggest that hot spot geometry is not the only mechanism giving rise to harmonic content in the latter. Fractional amplitude variability during the bursts is low; we cannot rule out the hypothesis that the fractional amplitude remains constant for bursts that do not exhibit photo-spheric radius expansion (PRE). There are no significant variations in frequency in any of the bursts except for the one burst that exhibits PRE. This burst exhibits a highly significant but small (approximate to 0.1 Hz) drop in frequency in the burst rise. The timescale of the frequency shift is slower than simple burning layer expansion models predict, suggesting that other mechanisms may be at work. C1 NASA, Goddard Space Flight Ctr, Xray Astrophys Lab, Greenbelt, MD 20771 USA. Univ Maryland, Dept Astron, College Pk, MD 20772 USA. RP Watts, AL (reprint author), NASA, Goddard Space Flight Ctr, Xray Astrophys Lab, Greenbelt, MD 20771 USA. EM anna@milkyway.gsfc.nasa.gov; stroh@clarence.gsfc.nasa.gov; craigm@milkyway.gsfc.nasa.gov NR 54 TC 29 Z9 29 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 NOV 20 PY 2005 VL 634 IS 1 BP 547 EP 564 DI 10.1086/496953 PN 1 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 985AF UT WOS:000233347800048 ER PT J AU Wood, MA Robertson, JR Simpson, JC Kawaler, SD O'Brien, MS Nather, RE Winget, DE Montgomery, MH Metcalfe, TS Jiang, XJ Leibowitz, EM Ibbetson, P O'Donoghue, D Zola, S Krzesinski, J Pajdosz, G Vauclair, G Dolez, N Chevreton, M Sullivan, DJ Kanaan, A Nitta, A AF Wood, MA Robertson, JR Simpson, JC Kawaler, SD O'Brien, MS Nather, RE Winget, DE Montgomery, MH Metcalfe, TS Jiang, XJ Leibowitz, EM Ibbetson, P O'Donoghue, D Zola, S Krzesinski, J Pajdosz, G Vauclair, G Dolez, N Chevreton, M Sullivan, DJ Kanaan, A Nitta, A TI DQ Herculis in profile: Whole Earth Telescope observations and smoothed particle hydrodynamics simulations of an edge-on cataclysmic variable system SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; binaries : close; hydrodynamics; novae, cataclysmic variables; stars : individual (DQ Her) ID ACCRETION DISKS; PERIOD CHANGES; CLOSE BINARIES; STARS; OSCILLATIONS; SUPERHUMPS; PULSATIONS; PHOTOMETRY; SPECTRUM; CYCLES AB The old nova DQ Herculis was the Whole Earth Telescope Northern Hemisphere target for the 1997 July campaign and was observed on four nights with the SARA 0.9 m telescope during 2003 June. We present updated ephemerides for the eclipse and 71 s timings. The Fourier transform displays power at the presumed white dwarf spin period of 71.0655 s, but no significant power at either 142 or 35.5 s. The mean pulsed light curve is obtained by folding on the orbital period modulus the mean ephemeris of the 71 s period, and from this we calculate an O - C phase diagram and amplitude versus orbital phase diagrams. In addition to the phase variations during eclipse ingress and egress, the WET data reveal significant phase variations outside of eclipse. These must result from the self-eclipse of a non-axisymmetric disk. We simulated the disk in DQ Her using smoothed particle hydrodynamics. We improve our effective spatial signal-to-noise ratio by combining 250 snapshots of the N = 20; 000 phase space solution over time to obtain a 5 million particle ensemble disk. From the surface shape of the ensemble disk, the radius and vertical height above the midplane of the rim of the reprocessing region can be derived as a function of azimuthal angle. From this profile we can calculate the O - C phase and amplitude diagrams as a function of inclination angle. The calculated O - C diagrams are a remarkably good match to the observed phase and amplitude variations of the 71 s signal. The best match is for inclination angle 89.degrees 7. C1 Florida Inst Technol, Dept Phys & Space Sci, Melbourne, FL 32901 USA. Florida Inst Technol, SARA Observ, Melbourne, FL 32901 USA. Appalachian State Univ, Dept Phys & Astron, Boone, NC 28608 USA. NASA, Range Syst Design & Dev Branch, Kennedy Space Ctr, FL 32899 USA. Iowa State Univ, Dept Phys, Ames, IA 50011 USA. Yale Univ, Dept Astron, New Haven, CT 06511 USA. Univ Texas, Dept Astron, Austin, TX 78712 USA. Univ Texas, McDonald Observ, Austin, TX 78712 USA. Univ Cambridge, Astron Inst, Cambridge CB3 0HA, England. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Chinese Acad Sci, Natl Astron Observ, Beijing Astron Observ, Beijing 100012, Peoples R China. Tel Aviv Univ, Dept Phys & Astron, IL-69978 Tel Aviv, Israel. Tel Aviv Univ, Wise Observ, IL-69978 Tel Aviv, Israel. S African Astron Observ, ZA-7935 Cape Town, South Africa. Jagiellonian Univ, Astron Observ, PL-30244 Krakow, Poland. Pedagog Univ, Mt Suhora Observ, PL-30024 Krakow, Poland. Univ Toulouse 3, Observ Midi Pyrenees, CNRS UMRS 5572, F-31400 Toulouse, France. DAEC, Observ Paris, F-92195 Meudon, France. Victoria Univ Wellington, Sch Chem & Phys Sci, Wellington, New Zealand. Univ Fed Santa Catarina, Dept Fis, BR-88040900 Florianopolis, SC, Brazil. Apache Point Observ, Sunspot, NM 88349 USA. RP Wood, MA (reprint author), Florida Inst Technol, Dept Phys & Space Sci, Melbourne, FL 32901 USA. EM wood@astro.fit.edu RI Metcalfe, Travis/A-9388-2008; OI Metcalfe, Travis/0000-0003-4034-0416; Kawaler, Steven/0000-0002-6536-6367 NR 57 TC 12 Z9 12 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 NOV 20 PY 2005 VL 634 IS 1 BP 570 EP 584 DI 10.1086/496957 PN 1 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 985AF UT WOS:000233347800050 ER PT J AU Rivera, EJ Lissauer, JJ Butler, RP Marcy, GW Vogt, SS Fischer, DA Brown, TM Laughlin, G Henry, GW AF Rivera, EJ Lissauer, JJ Butler, RP Marcy, GW Vogt, SS Fischer, DA Brown, TM Laughlin, G Henry, GW TI A similar to 7.5 M-circle plus planet orbiting the nearby star, GJ 876 SO ASTROPHYSICAL JOURNAL LA English DT Article DE planetary systems; planets and satellites : general; stars : individual (GJ 876) ID PRECISION RADIAL-VELOCITIES; EXTRASOLAR PLANETS; M-DWARF; SYSTEM; SIMULATIONS; EVOLUTION; MASS; VARIABILITY; PHOTOMETRY; TELESCOPE AB High-precision, high-cadence radial velocity monitoring over the past 8 yr at the W. M. Keck Observatory reveals evidence for a third planet orbiting the nearby (4.69 pc) dM4 star GJ 876. The residuals of three-body Newtonian fits, which include GJ 876 and Jupiter-mass companions b and c, show significant power at a periodicity of 1.9379 days. Self-consistently fitting the radial velocity data with a model that includes an additional body with this period significantly improves the quality of the fit. These four-body (three-planet) Newtonian fits find that the minimum mass of companion ''d'' is m sin i 5.89 +/- 0.54 M-circle plus and that its orbital period is 1.93776 ( +/- 7; 10(-5)) days. Assuming coplanar orbits, an inclination of the GJ 876 planetary system to the plane of the sky of similar to 50 degrees gives the best fit. This inclination yields a mass for companion d of m 7.53 +/- 0.70 M-circle plus, making it by far the lowest mass companion yet found around a main-sequence star other than our Sun. Precise photometric observations at Fairborn Observatory confirm low-level brightness variability in GJ 876 and provide the first explicit determination of the star's 96.7 day rotation period. Even higher precision short-term photometric measurements obtained at Las Campanas imply that planet d does not transit GJ 876. C1 Univ Calif Santa Cruz, Univ Calif Observ, Lick Observ, Santa Cruz, CA 95064 USA. NASA, Ames Res Ctr, Space Sci & Astrobiol Div, Moffett Field, CA 94035 USA. Carnegie Inst Washington, Dept Terr Magnetism, Washington, DC 20015 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. San Francisco State Univ, Dept Phys & Astron, San Francisco, CA 94132 USA. Natl Ctr Atmospher Res, High Altitude Observ, Boulder, CO 80307 USA. Tennessee State Univ, Ctr Excellence Informat Syst, Nashville, TN 37209 USA. Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. RP Rivera, EJ (reprint author), Univ Calif Santa Cruz, Univ Calif Observ, Lick Observ, 373 Interdisciplinary Sci, Santa Cruz, CA 95064 USA. EM rivera@ucolick.org RI Butler, Robert/B-1125-2009 NR 36 TC 325 Z9 328 U1 1 U2 7 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 NOV 20 PY 2005 VL 634 IS 1 BP 625 EP 640 DI 10.1086/491669 PN 1 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 985AF UT WOS:000233347800054 ER PT J AU Phillips, KJH Feldman, U Harra, LK AF Phillips, KJH Feldman, U Harra, LK TI X-ray observations of solar long-duration flares SO ASTROPHYSICAL JOURNAL LA English DT Article DE line : profiles; Sun : corona; Sun : flares; Sun : X-rays, gamma rays ID BRAGG CRYSTAL SPECTROMETER; DIELECTRONIC SATELLITE SPECTRA; LOOP-TOP KERNELS; MAGNETIC RECONNECTION; NONTHERMAL VELOCITY; YOHKOH; PLASMA; PHASE; OSCILLATIONS; PROMINENCES AB Yohkoh X-ray observations during the several-hour decay of six large solar flares show that the main emitting region is in the form of a bright loop-top source whose spatial extent well after the impulsive stage explains most of the broadening of S xv and Ca XIX X-ray lines, which would otherwise imply nonthermal velocities of 100 km s(-1) or more. During the decay of each event, the electron temperature and emission measure decline slowly. For the nearly disk center event of 1992 February 27, the volume increases and the deduced lower limit to the electron density Ne decreases from similar to 10(11) cm(-3) to just below 10(10) cm(-3). The nonuniform emission along the loops indicates that Spitzer heat conduction does not operate. If radiation is the only or main energy-loss mechanism, the lower limits to Ne imply upper limits to radiation cooling times of up to 10 hr, less than the flare decay time, so necessitating a continuing energy input. Although magnetic reconnection of previous broken open loops (the Kopp-Pneuman model) has been widely regarded as the source of energy in such flares, the small nonthermal velocities-only 20-50 km s(-1) as indicated by SUMER observations-and the lack of spectroscopic indicators of large inflows or outflows argue against it. Other flare models must also explain the relatively small nonthermal velocities. An alternative picture of loop oscillations recently seen in TRACE and Yohkoh data is proposed for the production of observed nonthermal velocities. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20575 USA. Artep Inc, Ellicott City, MD 21042 USA. Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England. RP Phillips, KJH (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM kennethjhphillips@yahoo.com OI Harra, Louise/0000-0001-9457-6200 NR 35 TC 15 Z9 15 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 NOV 20 PY 2005 VL 634 IS 1 BP 641 EP 650 DI 10.1086/491693 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 985AF UT WOS:000233347800055 ER PT J AU Bassani, L De Rosa, A Bazzano, A Bird, AJ Dean, AJ Gehrels, N Kennea, JA Malizia, A Molina, M Stephen, JB Ubertini, P Walter, R AF Bassani, L De Rosa, A Bazzano, A Bird, AJ Dean, AJ Gehrels, N Kennea, JA Malizia, A Molina, M Stephen, JB Ubertini, P Walter, R TI Is the integral IBIS source IGR J17204-3554 A gamma-ray-emitting galaxy hidden behind the molecular cloud NGC 6334? SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; gamma rays : observations; ISM : clouds; X-rays : general ID NGC 6334; STAR-FORMATION; CATALOG; REGIONS AB We report on the identification of a soft gamma-ray source, IGR J17204-3554, detected with IBIS, the Imager on Board the INTEGRAL Satellite. The source has a 20-100 keV flux of similar to 3 x 10(-11) ergs cm(-2) s(-1) and is spatially coincident with NGC 6334, a molecular cloud located in the Sagittarius arm of the Milky Way. Diffuse X-ray emission has been reported from this region by ASCA and interpreted as coming from five far-infrared cores located in the cloud. However, the combined ASCA spectrum with a 9 keV temperature was difficult to explain in terms of emission from young pre-main-sequence stars known to be embedded in the star-forming regions. Detection of gamma rays makes this interpretation even more unrealistic and suggests the presence of a high-energy source in or behind the cloud. Follow-up observations with Swift and archival Chandra data allow us to disentangle the NGC 6334 enigma by locating an extragalactic object with the proper spectral characteristics to explain the gamma-ray emission. The combined Chandra-IBIS spectrum is well fitted by an absorbed power law with Gamma = 1.2 +/- 0.1, N-H = (1.4 +/- 0.1) x 10(23) cm(-2), and an unabsorbed 2-10 keV flux of 0.5 x 10(-11) ergs cm(-2) s(-1). This column density is in excess of the Galactic value, implying that we are detecting a background galaxy concealed by the molecular cloud and further hidden by material located either in the galaxy itself or between IGR J17204 - 3554 and the cloud. C1 INAF, Ist Astrofis Spaziale & Fis Cosm, Sez Bologna, I-40129 Bologna, Italy. INAF, Ist Astrofis Spaziale & Fis Cosm, Sez Roma, I-00133 Rome, Italy. Univ Southampton, Sch Phys & Astron, Southampton SO17 1BJ, Hants, England. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Penn State Univ, Dept Astron & Astrophys, Davey Lab 525, University Pk, PA 16802 USA. INTEGRAL Sci Data Ctr, CH-1291 Versoix, Switzerland. RP Bassani, L (reprint author), INAF, Ist Astrofis Spaziale & Fis Cosm, Sez Bologna, I-40129 Bologna, Italy. RI Gehrels, Neil/D-2971-2012; OI De Rosa, Alessandra/0000-0001-5668-6863; Bazzano, Angela/0000-0002-2017-4396 NR 22 TC 10 Z9 10 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 NOV 20 PY 2005 VL 634 IS 1 BP L21 EP L24 DI 10.1086/498718 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 985AI UT WOS:000233348100006 ER PT J AU Gelfand, JD Lyubarsky, YE Eichler, D Gaensler, BM Taylor, GB Granot, J Newton-McGee, KJ Ramirez-Ruiz, E Kouveliotou, C Wijers, RAMJ AF Gelfand, JD Lyubarsky, YE Eichler, D Gaensler, BM Taylor, GB Granot, J Newton-McGee, KJ Ramirez-Ruiz, E Kouveliotou, C Wijers, RAMJ TI A rebrightening of the radio nebula associated with the 2004 December 27 giant flare from SGR 1806-20 SO ASTROPHYSICAL JOURNAL LA English DT Article DE pulsars : individual (SGR 1806-20); neutrinos; radio continuum : stars; shock waves; stars : magnetic fields; stars : neutron ID X-RAY PULSAR; MAGNETAR SGR-1806-20; RADIATIVE MECHANISM; ACCELERATION; CONSTRAINTS; REPEATERS; EMISSION; DISTANCE; SHOCK AB The 2004 December 27 giant gamma-ray flare detected from the magnetar SGR 1806 - 20 created an expanding radio nebula that we have monitored with the Australia Telescope Compact Array and the Very Large Array. These data indicate that there was an increase in the observed flux similar to 25 days after the initial flare that lasted for similar to 8 days, which we believe is the result of ambient material swept up and shocked by this radio nebula. For a distance to SGR 1806 - 20 of 15 kpc, using the properties of this rebrightening, we infer that the initial blast wave was dominated by baryonic material of mass M greater than or similar to 10(24.5) g. For an initial expansion velocity v similar to 0.7c derived in an accompanying paper), we infer that this material had an initial kinetic energy E greater than or similar to 10(44.5) ergs. If this material originated from the magnetar itself, it may have emitted a burst of ultra - high-energy (E greater than or similar to 1 TeV) neutrinos far brighter than that expected from other astrophysical sources. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Ben Gurion Univ Negev, Dept Phys, IL-84105 Beer Sheva, Israel. Stanford Univ, Kavli Inst Particle Astrophys & Cosmol, Stanford, CA 94309 USA. Natl Radio Astron Observ, Socorro, NM 87801 USA. Univ Sydney, Sch Phys, Sydney, NSW 2006, Australia. CSIRO, Australia Telescope Natl Facil, Epping, NSW 1710, Australia. Inst Adv Study, Princeton, NJ 08540 USA. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35805 USA. Univ Amsterdam, Astron Inst Anton Pannekoek, NL-1098 SJ Amsterdam, Netherlands. RP Gelfand, JD (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Gaensler, Bryan/F-8655-2010; LYUBARSKY, YURY/F-2362-2012; Gelfand, Joseph/F-1110-2015; OI Gelfand, Joseph/0000-0003-4679-1058; Gaensler, Bryan/0000-0002-3382-9558 NR 23 TC 29 Z9 29 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 NOV 20 PY 2005 VL 634 IS 1 BP L89 EP L92 DI 10.1086/498643 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 985AI UT WOS:000233348100023 ER PT J AU Georganopoulos, M Perlman, ES Kazanas, D AF Georganopoulos, M Perlman, ES Kazanas, D TI Is the core of M87 the source of its TeV emission? Implications for unified schemes SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; quasars : general; quasars : individual (M87); radiation mechanisms : nonthermal; X-rays : galaxies ID ACTIVE GALACTIC NUCLEI; BL LACERTAE OBJECT; GAMMA-RAY SOURCES; X-RAY; RADIO GALAXY; JET; RESOLUTION; LAC; DECELERATION; NGC-6251 AB M87 has recently been shown to be a TeV source that is likely to be variable. Based on this and on contemporaneous optical and X-ray monitoring, we argue that the source of the TeV emission is the core of M87 and not one of two jet knots ( HST-1 and A), with an X-ray brightness comparable to that of the core. We model the TeV emission in the core as inverse Compton (IC) emission from the base of the jet. Homogeneous models fail to reproduce the spectral energy distribution ( SED) and, in particular, the TeV flux. They also fail to comply with the unified scheme of BL Lacertae (BL) objects and FR I radio galaxies. A jet that decelerates from a Lorentz factor Gamma similar to 20 down to Gamma similar to 5 over a length of similar to 0.1 pc reproduces the observed SED of the M87 core and, when aligned with the line of sight, produces a SED similar to those of TeV BLs. The TeV flux in the decelerating jet model is successfully reproduced as upstream Compton (UC) scattering, a recently identified emission mechanism, in which energetic electrons of the upstream faster flow upscatter the low-energy photons produced in the slower downstream part of the flow. C1 Univ Maryland Baltimore Cty, Dept Phys, Joint Ctr Astrophys, Baltimore, MD 21250 USA. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. RP Univ Maryland Baltimore Cty, Dept Phys, Joint Ctr Astrophys, 1000 Hilltop Circle, Baltimore, MD 21250 USA. OI Perlman, Eric/0000-0002-3099-1664 NR 47 TC 44 Z9 44 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 NOV 20 PY 2005 VL 634 IS 1 BP L33 EP L36 DI 10.1086/498714 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 985AI UT WOS:000233348100009 ER PT J AU Mahabal, A Stern, D Bogosavljevic, M Djorgovski, SG Thompson, D AF Mahabal, A Stern, D Bogosavljevic, M Djorgovski, SG Thompson, D TI Discovery of an optically faint quasar at z=5.70 and implications for the faint end of the quasar luminosity function SO ASTROPHYSICAL JOURNAL LA English DT Article DE early universe; quasars : general; quasars : individual (RD J114816.2+525339) ID DIGITAL SKY SURVEY; DEEP FIELD-NORTH; Z-GREATER-THAN-5.7 QUASARS; ADDITIONAL QUASARS; SDSS J1030+0524; X-RAY; REIONIZATION; QSO; Z-SIMILAR-TO-6; SPECTROSCOPY AB We present observations of an optically faint quasar, RD J114816.2 + 525339 (hereafter RD J1148 similar to 5253), discovered from deep multicolor observations of the field around the z=6.42 quasar SDSS J1148 + 5251. The two quasars have a projected separation of 109 '' and both are outliers in r-z versus z-j color-color space. Keck spectroscopy reveals RD J1148 + 5253 to be a broad absorption line quasar at z = 5.70 z(AB) = 23.0, RD J1148 + 5253 is 3.3 mag fainter than SDSS J1148 + 5251, making it the faintest quasar known at. This z > 5.5 object was identified in a survey of approximate to 2.5 deg(2). The implied surface density of quasars at these redshifts and luminosities is broadly consistent with previous extrapolations of the faint end of the quasar luminosity function and supports the idea that active galaxies provide only a minor component of the reionizing ultraviolet flux at these redshifts. C1 CALTECH, Palomar Observ, Pasadena, CA 91125 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Mahabal, A (reprint author), CALTECH, Palomar Observ, Mail Stop 105-24, Pasadena, CA 91125 USA. EM aam@astro.caltech.edu; stern@thisvi.jpl.nasa.gov; milan@astro.caltech.edu; george@astro.caltech.edu; djt@irastro.caltech.edu NR 30 TC 26 Z9 26 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 NOV 20 PY 2005 VL 634 IS 1 BP L9 EP L11 DI 10.1086/498847 PN 2 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 985AI UT WOS:000233348100003 ER PT J AU Taylor, GB Gelfand, JD Gaensler, BM Granot, J Kouveliotou, C Fender, RP Ramirez-Ruiz, E Eichler, D Lyubarsky, YE Garrett, M Wijers, RAMJ AF Taylor, GB Gelfand, JD Gaensler, BM Granot, J Kouveliotou, C Fender, RP Ramirez-Ruiz, E Eichler, D Lyubarsky, YE Garrett, M Wijers, RAMJ TI The growth, polarization, and motion of the radio afterglow from the giant flare from SGR 1806-20 SO ASTROPHYSICAL JOURNAL LA English DT Article DE pulsars : individual (SGR 1806-20); radio continuum : general; stars : flare; stars : neutron; stars : winds, outflows ID MAGNETAR SGR-1806-20; DISTANCE; NEBULA AB The extraordinary giant flare ( GF) of 2004 December 27 from the soft gamma repeater SGR 1806 - 20 was followed by a bright radio afterglow. We present an analysis of VLA observations of this radio afterglow from SGR 1806 - 20, consisting of previously reported 8.5 GHz data covering days 7 - 20 after the GF, plus new observations at 8.5 and 22 GHz from day 24 to 81. We detect motion in the flux centroid of the afterglow, at an average velocity of ( 0.26 +/- 0.03) c ( assuming a distance of 15 kpc) at a position angle of - 45 degrees. This motion, in combination with the growth and polarization measurements, suggests an asymmetric outflow, mainly from one side of the magnetar. We find a deceleration in the expansion, from similar to 9 to < 5 mas day(-1). The time of deceleration is roughly coincident with the rebrightening in the radio light curve, as expected to result when the ejecta from the GF sweeps up enough of the external medium and transitions from a coasting phase to the Sedov-Taylor regime. The radio afterglow is elongated and maintains a 2 : 1 axis ratio with an average position angle of - 40 degrees ( north through east), oriented perpendicular to the average intrinsic linear polarization angle. C1 Kavli Inst Particle Astrophys & Cosmol, Menlo Pk, CA 94025 USA. Natl Radio Astron Observ, Socorro, NM 87801 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35805 USA. Univ Southampton, Sch Phys & Astron, Southampton SO17 1BJ, Hants, England. Inst Adv Study, Princeton, NJ 08540 USA. Ben Gurion Univ Negev, Dept Phys, IL-84105 Beer Sheva, Israel. VLBI Europe, Joint Inst, NL-7990 AA Dwingeloo, Netherlands. Univ Amsterdam, Astron Inst Anton Pannekoek, NL-1098 SJ Amsterdam, Netherlands. RP Taylor, GB (reprint author), Kavli Inst Particle Astrophys & Cosmol, Menlo Pk, CA 94025 USA. RI Gaensler, Bryan/F-8655-2010; LYUBARSKY, YURY/F-2362-2012; Gelfand, Joseph/F-1110-2015; OI Gelfand, Joseph/0000-0003-4679-1058; Wijers, Ralph/0000-0002-3101-1808; Gaensler, Bryan/0000-0002-3382-9558 NR 16 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 NOV 20 PY 2005 VL 634 IS 1 BP L93 EP L96 DI 10.1086/491648 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 985AI UT WOS:000233348100024 ER PT J AU Kodaira, S Hareyama, M Hasebe, N Miyachi, T Sakurai, K Binns, WR Cummings, JR Israel, MH Link, JT Rauch, BF Scott, LM Geier, S Mewaldt, RA Barbier, LM Mitchell, JW De Nolfo, GA Streitmatter, RE Waddington, CJ AF Kodaira, S Hareyama, M Hasebe, N Miyachi, T Sakurai, K Binns, WR Cummings, JR Israel, MH Link, JT Rauch, BF Scott, LM Geier, S Mewaldt, RA Barbier, LM Mitchell, JW De Nolfo, GA Streitmatter, RE Waddington, CJ TI The attenuation length of cosmic ray iron in the atmosphere obtained by TIGER experiment SO INTERNATIONAL JOURNAL OF MODERN PHYSICS A LA English DT Article; Proceedings Paper CT 19th European Cosmic Ray Symposium CY AUG 30-SEP 03, 2003 CL Florence, ITALY SP Inst Nazl Fis Nucl, Univ Firenze, Dept Fis, Municipalita Firenze, Ente Cassa Risparmio Firenze DE interaction mean free path; cosmic ray; heavy nuclei; elemental abundance ID CROSS-SECTIONS; FRAGMENTATION; HYDROGEN; TARGETS; NUCLEI; CHARGE; CARBON; FE-56 AB A precise measurement of elemental abundances of galactic cosmic rays from charges Z = 20 to 34 was made by TIGER balloon experiment. Using the various path lengths in the atmosphere between 4 and 16 g/cm(2) from the TIGER flight data, we derived the attenuation length of iron nuclei with the energy above 2.5 GeV/n in the atmosphere. As the result, we obtained the attenuation length of 15.5 +/- 0.6 g/cm(2) which is consistent with previous results of balloon measurements. C1 Waseda Univ, Adv Res Inst Sci & Engn, Shinjuku Ku, Tokyo 1698555, Japan. Washington Univ, St Louis, MO 63130 USA. CALTECH, Pasadena, CA 91125 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Minnesota, Minneapolis, MN 55455 USA. RP Kodaira, S (reprint author), Waseda Univ, Adv Res Inst Sci & Engn, Shinjuku Ku, 3-4-1 Okubo, Tokyo 1698555, Japan. RI de Nolfo, Georgia/E-1500-2012; Kodaira, Satoshi/H-9836-2012 NR 7 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA 5 TOH TUCK LINK, SINGAPORE 596224, SINGAPORE SN 0217-751X J9 INT J MOD PHYS A JI Int. J. Mod. Phys. A PD NOV 20 PY 2005 VL 20 IS 29 BP 6702 EP 6704 DI 10.1142/S0217751X05029861 PG 3 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 003SU UT WOS:000234702700030 ER PT J AU Nazarenko, L Menon, S AF Nazarenko, L Menon, S TI Varying trends in surface energy fluxes and associated climate between 1960 and 2002 based on transient climate simulations SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID BLACK CARBON AEROSOLS; SOLAR-RADIATION; TEMPERATURE; CYCLE; CHINA; HAZE AB The observed reduction in land surface radiation over the last several decades ( 1960 - 1990), the so-called "dimming effect,'' and the more recent evidence of a reversal in "dimming'' over some locations beyond 1990 suggest several consequences on climate, notably on the hydrological cycle. Such a reduction in radiation should imply reduced surface temperature (T-s) and precipitation, which have not occurred. We have investigated the possible causes for the above climate features using a climate model coupled to a dynamic ocean model under natural and anthropogenic conditions. To isolate the aerosol influence on surface radiation trends, we have analyzed transient climate simulations from 1960 to 2002 with and without anthropogenic aerosols. Based on a linear trend with aerosol effects included, the global mean change in the surface solar radiation absorbed over land is - 0.021 +/- 0.0033 Wm(-2) yr(-1). Although the overall trend is negative, we do note a reversal in dimming after 1990, consistent with observations. Without aerosol effects, the surface solar radiation absorbed over land increases throughout 1960 to 2002, mainly due to the decrease in cloud cover associated with increased greenhouse warming. In spite of a simulated increase in T-s of 0.012 K yr(-1) for 1960 to 2002, the global mean latent heat flux and associated intensity of the hydrological cycle decrease overall, however with increases over some land locations due mainly to moisture advection. Simulated changes correspond more closely to observed changes when accounting for aerosol effects on climate. C1 Columbia Univ, NASA, Goddard Inst Space Studies, New York, NY 10025 USA. Lawrence Berkeley Natl Lab, Berkeley, CA USA. RP Columbia Univ, NASA, Goddard Inst Space Studies, New York, NY 10025 USA. EM lnazarenko@giss.nasa.gov NR 31 TC 24 Z9 25 U1 0 U2 3 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 NOV 19 PY 2005 VL 32 IS 22 AR L22704 DI 10.1029/2005GL024089 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 988II UT WOS:000233586600005 ER PT J AU Emslie, AG Dennis, BR Holman, GD Hudson, HS AF Emslie, AG Dennis, BR Holman, GD Hudson, HS TI Refinements to flare energy estimates: A followup to ''Energy partition in two solar flare/CME events'' by A. G. Emslie et al. SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID EMISSION AB Emslie et al. (2004) reported estimates of the energy in the different flare and coronal mass ejection (CME) components of two major solar events with unprecedented observational coverage, one on 21 April 2002 and the other on 23 July 2002. On the basis of these estimates, it appeared that the summed energy content of the different flare components was significantly lower than the total energy of the CME, leading them to reach the "cautious" conclusion that "in both events the coronal mass ejection has the dominant component of the released energy," amounting to approximately 30% of the available magnetic energy. In this note we present revised estimates of the flare thermal energies in the two events and also add a consideration of the total radiant energy of the events obtained by scaling the measured soft X-ray luminosity based on Solar Radiation and Climate Experiment (SORCE) total solar irradiance measurements for the 28 October 2003 event. Recognizing that many of these energetic components are interrelated, we also take care to distinguish between "primary" components of energy (e.g., the magnetic field), "intermediate" components (e.g., accelerated particles and thermal plasma), and "final" components (e.g., kinetic energy of ejecta, radiant energy in various wave bands). We note that since the values of these components are not all independent, careful tallying is necessary to arrive at an overall energy budget for the event. The best estimates for the energies of the various components still show that the CME contains the greatest fraction of the released energy in both events. However, given the large uncertainties in the energies of the different flare components and the higher estimates of radiant energy obtained by scaling from the SORCE measurements, the results are also consistent with the flare and CME energies in both events being comparable, with a common value of similar to 10(32) ergs. C1 Oklahoma State Univ, Dept Phys, Stillwater, OK 74078 USA. NASA, Goddard Space Flight Ctr, Solar Phys Branch, Greenbelt, MD 20771 USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. RP Emslie, AG (reprint author), Oklahoma State Univ, Dept Phys, Stillwater, OK 74078 USA. EM gordon.emslie@okstate.edu; brian.r.dennis@nasa.gov; gordon.d.holman@nasa.gov; hhudson@ssl.berkeley.edu RI Dennis, Brian/C-9511-2012; Holman, Gordon/C-9548-2012 NR 10 TC 99 Z9 99 U1 0 U2 0 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 NOV 19 PY 2005 VL 110 IS A11 AR A11103 DI 10.1029/2005JA011305 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 988IY UT WOS:000233588800008 ER PT J AU Feldstein, YI Levitin, AE Kozyra, JU Tsurutani, BT Prigancova, A Alperovich, L Gonzalez, WD Mall, U Alexeev, II Gromova, LI Dremukhina, LA AF Feldstein, YI Levitin, AE Kozyra, JU Tsurutani, BT Prigancova, A Alperovich, L Gonzalez, WD Mall, U Alexeev, II Gromova, LI Dremukhina, LA TI Self-consistent modeling of the large-scale distortions in the geomagnetic field during the 24-27 September 1998 major magnetic storm SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID RING CURRENT; INNER MAGNETOSPHERE; AURORAL OVAL; EARTHS MAGNETOSPHERE; ULTRAVIOLET IMAGER; ELECTRIC-FIELDS; TIME-VARIATION; 2-PHASE DECAY; PLASMA SHEET; POLAR AB A new self-consistent version of a time-dependent magnetospheric paraboloid model is presented and tested on the 24-27 September 1998 magnetic storm interval (minimum Dst = -207 nT). The model uses DMSP satellite data to identify the location of the inner boundary of the magnetotail current sheet and the magnetic flux in the lobes and their variations with time. These inputs plus upstream solar wind dynamic pressure and IMF B-z values are used to iteratively model the Earth's field during the storm. Several interesting results with important consequences are obtained: (1) the model tail field strength at the Earth's surface (DT = -134 nT) is a significant fraction of the ring current value (DR = -167 nT); (2) the movement of the tail current sheet inward to L = 3.5-4.0 at storm maximum is consistent with geosynchronous magnetic field data; (3) at the Earth's surface the Chapman-Ferraro magnetopause current field (DCF = 117 nT) is almost equal at storm maximum to the value from the tail current, thus the fields from the two systems nearly cancel; (4) the magnetic flux from the polar cap in the course of the magnetic storm main phase approximately doubles in comparison with the magneto-quiet interval just before the storm onset; this fact shows that the driven processes prevail over dissipation processes throughout the storm main phase; (5) the large-scale internal currents in the magnetosphere (ring current, field-aligned currents, and magnetotail current) have significant influence on the shape and size of the magnetosphere; the location of the magnetopause subsolar point is different from that obtained by extrapolation of empirical results taken during high geomagnetic activity intervals and from magnetospheric models that do not include feedback from internal magnetospheric currents. C1 Inst Terr Magnetism Ionosphere & Radio Wave Propa, Troitsk 142190, Moscow Region, Russia. Univ Michigan, Space Phys Res Lab, Ann Arbor, MI 48109 USA. Jet Prop Lab, Pasadena, CA 9109 USA. Slovak Acad Sci, Inst Geophys, Bratislava 84528, Slovakia. Tel Aviv Univ, Dept Geophys & Planetary Sci, IL-69978 Tel Aviv, Israel. Ist Pesquisas Especiais, BR-12201970 Sao Paulo, Brazil. Max Planck Inst Aeron, D-37191 Katlenburg Lindau, Germany. Moscow MV Lomonosov State Univ, Inst Nucl Phys, Moscow 119899, Russia. RP Feldstein, YI (reprint author), Inst Terr Magnetism Ionosphere & Radio Wave Propa, Troitsk 142190, Moscow Region, Russia. EM aifeld@aol.com; aelevitin@yandex.ru; jukozyra@engin.umich.edu; btsurutani@jplsp.jpl.nasa.gov; geofpria@savba.sk; leonid@frodo.tau.ac.il; gonzalez@dge.inpe.br; mall@linmpi.mpg.de; alexeev@dec1.npi.msu.su; lgromova@izmiran.troitsk.ru RI Alexeev, Igor/G-8773-2011 NR 81 TC 17 Z9 17 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-SPACE JI J. Geophys. Res-Space Phys. PD NOV 19 PY 2005 VL 110 IS A11 AR A11214 DI 10.1029/2004JA010584 PG 27 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 988IY UT WOS:000233588800002 ER PT J AU Breon, FM O'Brien, DM Spinhirne, JD AF Breon, FM O'Brien, DM Spinhirne, JD TI Scattering layer statistics from space borne GLAS observations SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID GLOBAL OBSERVATIONS; CARBON BUDGET; CLOUD; CO2 AB Cloud and aerosol layers detected by the space borne Geoscience Laser Altimeter System (GLAS) are used to derive statistics of clear and almost clear atmospheres, the latter defined to be those with some scattering material but total optical thickness less than 0.2. Such statistics are needed to evaluate the potential coverage of NASA's forthcoming Orbital Carbon Observatory. The global fraction of clear cases is approximately 15%, with large scale spatial structures similar to those found by passive sensors. The spatial distribution of almost clear cases is similar to that for clear, with global fraction approximately 20%. The mean altitude of optically thin scattering layers is generally below one kilometer, indicating that they are composed mostly of boundary layer aerosol rather than high altitude cloud. The spatial correlation function of clear cases is accurately reproduced by the analytical function F(d) = exp[-(d/d(0))(0.5)], where d(0) is a correlation scale length. Between 60N and 60S, d(0) shows little zonal variation, and its average value is 320 km. Over the Arctic d(0) falls to 250 km, but rises to 450 km over the Antarctic. C1 CEA, DSM, LSCE, Lab Sci Climat & Environm, F-91191 Gif Sur Yvette, France. Colorado State Univ, Dept Atmospher Sci, Ft Collins, CO 80523 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Breon, FM (reprint author), CEA, DSM, LSCE, Lab Sci Climat & Environm, F-91191 Gif Sur Yvette, France. EM fmbreon@cea.fr RI Velazco, Voltaire/H-2280-2011; Breon, Francois-Marie/M-4639-2016; Notholt, Justus/P-4520-2016 OI Velazco, Voltaire/0000-0002-1376-438X; Breon, Francois-Marie/0000-0003-2128-739X; Notholt, Justus/0000-0002-3324-885X NR 12 TC 37 Z9 38 U1 1 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 NOV 18 PY 2005 VL 32 IS 22 AR L22802 DI 10.1029/2005GL023825 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 988IH UT WOS:000233586500001 ER PT J AU Chahine, M Barnet, C Olsen, ET Chen, L Maddy, E AF Chahine, M Barnet, C Olsen, ET Chen, L Maddy, E TI On the determination of atmospheric minor gases by the method of vanishing partial derivatives with application to CO2 SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID RADIATIVE-TRANSFER; AIRS/AMSU/HSB; PARAMETERS AB We present a general method for the determination of minor gases in the troposphere from high spectral resolution observations. In this method, we make use of a general property of the total differential of multi-variable functions to separate the contributions of each individual minor gas. We have applied this method to derive the mixing ratio of carbon dioxide in the mid-troposphere using data from the Atmospheric Infrared Sounder ( AIRS) currently flying on the NASA Aqua Mission. We compare our results to the aircraft flask CO2 measurements obtained by H. Matsueda et al. over the western Pacific and demonstrate skill in tracking the measured 5 ppmv seasonal variation with an accuracy of 0.43 +/- 1.20 ppmv. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Natl Environm Satellite Data & Informat Serv, NOAA, Camp Springs, MD 20746 USA. QSS Grp Inc, Lanham, MD 20706 USA. RP Chahine, M (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,Mail Code 180-600A, Pasadena, CA 91109 USA. EM chahine@jpl.nasa.gov RI Maddy, Eric/G-3683-2010; Barnet, Christopher/F-5573-2010 OI Maddy, Eric/0000-0003-1151-339X; NR 15 TC 84 Z9 93 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 NOV 18 PY 2005 VL 32 IS 22 AR L22803 DI 10.1029/2005GL024165 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 988IH UT WOS:000233586500002 ER PT J AU Caldeira, RMA Marchesiello, P Nezlin, NP DiGiacomo, PM McWilliams, JC AF Caldeira, RMA Marchesiello, P Nezlin, NP DiGiacomo, PM McWilliams, JC TI Island wakes in the Southern California Bight SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID CURRENT SYSTEM; MADEIRA ISLAND; SANTA-MONICA; OCEAN; SEA; FLOW; MASS; EDDIES; WATERS; MESOZOOPLANKTON AB Wind- and current-induced island wakes were investigated using a multiplatform approach of in situ, remote sensing, and numerical model simulations for the Southern California Bight (SCB). Island wind wakes are a result of sheltering from the wind, with weak wind mixing, strong heat storage, and consequent high sea surface temperature (SST). Wind wakes around Santa Catalina Island are most persistent during spring and summer months. Current wakes, caused by the disruption of the poleward traveling California Countercurrent, induce eddies to form off the north end of Catalina Island, and these move poleward every 9-12 days. Current wake eddies induce strong mixing, with low SST and high-density sea surface signatures, whereas wind wakes induce high sea surface temperature signatures associated with the formation of a well-defined shallow thermocline. Current wake eddies vary from 1 to 30 km in diameter. From numerical solutions we predicted the frequency of occurrence of current-induced wakes off Santa Catalina Island. Wind wakes were also observed off all the other islands of the SCB as seen from the analysis of synthetic aperture radar data. Time series analysis of the island mass effect phenomenon has shown a concurrence of low SST and high sea surface chlorophyll for Santa Catalina, San Nicholas, and San Clemente islands that might be related to the seasonality of the California Current and California Countercurrent. Future oceanographic research in the SCB should not ignore the occurrence of wind- and current-induced island features since they may be important in the transport and/or retention of nutrients, pollutants, and plankton. C1 Univ Calif Los Angeles, Los Angeles Marine Sci Ctr, Los Angeles, CA USA. So Calif Coastal Water Res Project, Westminster, CA 92683 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Calif Los Angeles, Dept Geophys & Planetary Phys, Los Angeles, CA 90095 USA. RP Caldeira, RMA (reprint author), Univ Madeira, Ctr Macaronesian Studies, P-9000390 Funchal, Madeira Island, Portugal. EM rui.caldeira@uma.pt RI DiGiacomo, Paul/F-5584-2010; Caldeira, Rui/J-9829-2013 OI DiGiacomo, Paul/0000-0003-4550-1899; Caldeira, Rui/0000-0001-8805-3016 NR 52 TC 25 Z9 25 U1 1 U2 6 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 NOV 18 PY 2005 VL 110 IS C11 AR C11012 DI 10.1029/2004JC002675 PG 26 WC Oceanography SC Oceanography GA 988IT UT WOS:000233588100003 ER PT J AU Nghiem, SV Van Woert, ML Neumann, G AF Nghiem, SV Van Woert, ML Neumann, G TI Rapid formation of a sea ice barrier east of Svalbard SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID BARENTS SEA; POLAR FRONT; OCEAN; HALOCLINE; HEAT AB Daily SeaWinds scatterometer images acquired by the QuikSCAT satellite show an elongated sea ice feature that formed very rapidly (similar to 1-2 days) in November 2001 east of Svalbard over the Barents Sea. This sea ice structure, called "the Svalbard sea ice barrier,'' spanning approximately 10 degrees in longitude and 2 degrees in latitude, restricts the sea route and poses a significant navigation hazard. The secret of its formation appears to lie in the bottom of the sea: A comparison between bathymetry from the International Bathymetric Chart of the Arctic Ocean data and the pattern of sea ice formation from scatterometer data reveals that the sea ice barrier conforms well with and stretches above a deep elongated channel connecting the Franz Josef-Victoria Trough to the Hinlopen Basin between Svalbard and Franz Josef Land. Historic hydrographic data from this area indicate that this sea channel contains cold Arctic water less than 50 m below the surface. Strong and persistent cold northerly winds force strong heat loss from this shallow surface layer, leading to the rapid formation of the sea ice barrier. Heat transfer rates estimated from European Centre for Medium-Range Weather Forecasts temperature and wind data over this region suggest that the surface water along the deep channel can be rapidly cooled to the freezing point. Scatterometer results in 1999-2003 show that sea ice forms in this area between October and December. Understanding the ice formation mechanisms helps to select appropriate locations for deployment of buoys measuring wind and air-sea temperature profile and to facilitate ice monitoring, modeling, and forecasting. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. NOAA, Natl Ice Ctr, Suitland, MD USA. RP Nghiem, SV (reprint author), CALTECH, Jet Prop Lab, MS 300-235,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM son.v.nghiem@jpl.nasa.gov; mvanwoer@nsf.gov NR 25 TC 16 Z9 16 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-OCEANS JI J. Geophys. Res.-Oceans PD NOV 18 PY 2005 VL 110 IS C11 AR C11013 DI 10.1029/2004JC002654 PG 11 WC Oceanography SC Oceanography GA 988IT UT WOS:000233588100001 ER PT J AU Komjathy, A Sparks, L Wilson, BD Mannucci, AJ AF Komjathy, A Sparks, L Wilson, BD Mannucci, AJ TI Automated daily processing of more than 1000 ground-based GPS receivers for studying intense ionospheric storms SO RADIO SCIENCE LA English DT Article ID SATELLITE AB As the number of ground-based and space-based receivers tracking the Global Positioning System (GPS) satellites steadily increases, it is becoming possible to monitor changes in the ionosphere continuously and on a global scale with unprecedented accuracy and reliability. As of August 2005, there are more than 1000 globally distributed dual-frequency GPS receivers available using publicly accessible networks including, for example, the International GPS Service and the continuously operating reference stations. To take advantage of the vast amount of GPS data, researchers use a number of techniques to estimate satellite and receiver interfrequency biases and the total electron content (TEC) of the ionosphere. Most techniques estimate vertical ionospheric structure and, simultaneously, hardware-related biases treated as nuisance parameters. These methods often are limited to 200 GPS receivers and use a sequential least squares or Kalman filter approach. The biases are later removed from the measurements to obtain unbiased TEC. In our approach to calibrating GPS receiver and transmitter interfrequency biases we take advantage of all available GPS receivers using a new processing algorithm based on the Global Ionospheric Mapping (GIM) software developed at the Jet Propulsion Laboratory. This new capability is designed to estimate receiver biases for all stations. We solve for the instrumental biases by modeling the ionospheric delay and removing it from the observation equation using precomputed GIM maps. The precomputed GIM maps rely on 200 globally distributed GPS receivers to establish the "background'' used to model the ionosphere at the remaining 800 GPS sites. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Komjathy, A (reprint author), CALTECH, Jet Prop Lab, M-S 138-308,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM attila.komjathy@jpl.nasa.gov RI Mannucci, Anthony/A-1349-2007 OI Mannucci, Anthony/0000-0003-2391-8490 NR 8 TC 86 Z9 86 U1 2 U2 7 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 NOV 18 PY 2005 VL 40 IS 6 AR RS6006 DI 10.1029/2005RS003279 PG 11 WC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications SC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications GA 988JB UT WOS:000233589200002 ER PT J AU Joughin, I Bindschadler, RA King, MA Voigt, D Alley, RB Anandakrishnan, S Horgan, H Peters, L Winberry, P Das, SB Catania, G AF Joughin, I Bindschadler, RA King, MA Voigt, D Alley, RB Anandakrishnan, S Horgan, H Peters, L Winberry, P Das, SB Catania, G TI Continued deceleration of Whillans Ice Stream, West Antarctica SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID GROUNDING-LINE RETREAT; BALANCE; SHELF; ACCELERATION; FLUCTUATIONS; DISCHARGE; VELOCITY; COLLAPSE; GLACIER AB Earlier observations indicated that Whillans Ice Stream slowed from 1973 to 1997. We collected new GPS observations of the ice stream's speed in 2003 and 2004. These data show that the ice stream is continuing to decelerate at rates of about 0.6%/ yr(2), with faster rates near the grounding line. Our data also indicate that the deceleration extends over the full width of the ice plain. Extrapolation of the deceleration trend suggests the ice stream could stagnate sometime between the middle of the 21st and 22nd Centuries. C1 Univ Washington, Appl Phys Lab, Polar Sci Ctr, Seattle, WA 98105 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Newcastle Univ, Sch Civil Engn & Geosci, Newcastle Upon Tyne NE1 7RU, Tyne & Wear, England. Penn State Univ, Dept Geosci, University Pk, PA 16802 USA. Penn State Univ, Earth & Environm Syst Inst, University Pk, PA 16802 USA. Woods Hole Oceanog Inst, Dept Geol & Geophys, Woods Hole, MA 02543 USA. Univ Texas, Inst Geophys, Austin, TX 78759 USA. RP Univ Washington, Appl Phys Lab, Polar Sci Ctr, 1013 NE 40th St, Seattle, WA 98105 USA. EM ian@apl.washington.edu RI Joughin, Ian/A-2998-2008; King, Matt/B-4622-2008 OI Joughin, Ian/0000-0001-6229-679X; King, Matt/0000-0001-5611-9498 NR 23 TC 45 Z9 45 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 NOV 17 PY 2005 VL 32 IS 22 AR L22501 DI 10.1029/2005GL024319 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 988IE UT WOS:000233586200006 ER PT J AU Davies, S Mann, GW Carslaw, KS Chipperfield, MP Kettleborough, JA Santee, ML Oelhaf, H Wetzel, G Sasano, Y Sugita, T AF Davies, S Mann, GW Carslaw, KS Chipperfield, MP Kettleborough, JA Santee, ML Oelhaf, H Wetzel, G Sasano, Y Sugita, T TI 3-D microphysical model studies of Arctic denitrification: comparison with observations SO ATMOSPHERIC CHEMISTRY AND PHYSICS LA English DT Article ID POLAR STRATOSPHERIC CLOUDS; LARGE HNO3-CONTAINING PARTICLES; ATMOSPHERIC SPECTROMETER ILAS; EXPLAIN DENITRIFICATION; HOMOGENEOUS NUCLEATION; WINTER STRATOSPHERE; VERTICAL PROFILES; FEBRUARY 1995; COLD WINTERS; VORTEX AB Simulations of Arctic denitrification using a 3-D chemistry-microphysics transport model are compared with observations for the winters 1994/95, 1996/97 and 1999/2000. The model of Denitrification by Lagrangian Particle Sedimentation (DLAPSE) couples the full chemical scheme of the 3-D chemical transport model, SLIMCAT, with a nitric acid trihydrate (NAT) growth and sedimentation scheme. We use observations from the Microwave Limb Sounder (MLS) and Improved Limb Atmospheric Sounder (ILAS) satellite instruments, the balloon-borne Michelsen Interferometer for Passive Atmospheric Sounding (MIPASB), and the in situ NOy instrument on-board the ER-2. As well as directly comparing model results with observations, we also assess the extent to which these observations are able to validate the modelling approach taken. For instance, in 1999/ 2000 the model captures the temporal development of denitrification observed by the ER-2 from late January into March. However, in this winter the vortex was already highly denitrified by late January so the observations do not provide a strong constraint on the modelled rate of denitrification. The model also reproduces the MLS observations of denitrification in early February 2000. In 1996/97 the model captures the timing and magnitude of denitrification as observed by ILAS, although the lack of observations north of similar to 67 degrees N in the beginning of February make it difficult to constrain the actual timing of onset. The comparison for this winter does not support previous conclusions that denitrification must be caused by an ice-mediated process. In 1994/95 the model notably underestimates the magnitude of denitrification observed during a single balloon flight of the MIPAS-B instrument. Agreement between model and MLS HNO3 at 68 hPa in mid-February 1995 is significantly better. Sensitivity tests show that a 1.5 K overall decrease in vortex temperatures, or a factor 4 increase in assumed NAT nucleation rates, produce the best statistical fit to MLS observations. Both adjustments would be required to bring the model into agreement with the MIPAS-B observations. The agreement between the model and observations suggests that a NAT-only denitrification scheme ( without ice), which was discounted by previous studies, must now be considered as one mechanism for the observed Arctic denitrification. The timing of onset and the rate of denitrification remain poorly constrained by the available observations. C1 Univ Leeds, Inst Atmospher Sci, Sch Earth & Environm, Leeds LS2 9JT, W Yorkshire, England. Rutherford Appleton Lab, Oxford, England. CALTECH, Jet Prop Lab, Pasadena, CA USA. Forschungszentrum Karlsruhe, Inst Meteorol & Klimaforsch, D-76021 Karlsruhe, Germany. Natl Inst Environm Studies, Ibaraki, Japan. RP Univ Leeds, Inst Atmospher Sci, Sch Earth & Environm, Leeds LS2 9JT, W Yorkshire, England. EM stewart@env.leeds.ac.uk RI Sasano, Yasuhiro/C-2927-2009; Wetzel, Gerald/A-7065-2013; Oelhaf, Hermann/A-7895-2013; Carslaw, Ken/C-8514-2009; Chipperfield, Martyn/H-6359-2013; OI Sasano, Yasuhiro/0000-0001-7470-5642; Carslaw, Ken/0000-0002-6800-154X; Chipperfield, Martyn/0000-0002-6803-4149; Sugita, Takafumi/0000-0002-0508-7040 NR 53 TC 10 Z9 10 U1 1 U2 9 PU COPERNICUS GESELLSCHAFT MBH PI GOTTINGEN PA BAHNHOFSALLEE 1E, GOTTINGEN, 37081, GERMANY SN 1680-7316 EI 1680-7324 J9 ATMOS CHEM PHYS JI Atmos. Chem. Phys. PD NOV 16 PY 2005 VL 5 BP 3093 EP 3109 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 984PW UT WOS:000233317800003 ER PT J AU Hsu, LL Champion, HC Manci, E Diwan, B Schimel, D Cochard, A Wang, X Holtzclaw, JD Schechter, A Noguchi, CT Gladwin, M AF Hsu, LL Champion, HC Manci, E Diwan, B Schimel, D Cochard, A Wang, X Holtzclaw, JD Schechter, A Noguchi, CT Gladwin, M TI Spontaneous pulmonary hypertension in Transgenic sickle cell mice - Hemodynamics and histology suggest abnormal nitric oxide production and scavenging. SO BLOOD LA English DT Meeting Abstract CT 47th Annual Meeting of the American-Society-of-Hematology CY DEC 10-13, 2005 CL Atlanta, GA SP Amer Soc Hematol C1 St Christophers Hosp Children, Marian Anderson Sickle Cell Ctr, Philadelphia, PA 19133 USA. Johns Hopkins Med Inst, Baltimore, MD 21205 USA. Univ S Alabama, Sickle Cell Pathol Unit, Mobile, AL 36688 USA. NCI, SAIC, Frederick, MD 21701 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. NIH, Bethesda, MD 20892 USA. RI Hsu, Lewis/A-3360-2008 NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC HEMATOLOGY PI WASHINGTON PA 1900 M STREET. NW SUITE 200, WASHINGTON, DC 20036 USA SN 0006-4971 J9 BLOOD JI Blood PD NOV 16 PY 2005 VL 106 IS 11 MA 208 BP 64A EP 64A PN 1 PG 1 WC Hematology SC Hematology GA 986CF UT WOS:000233426000209 ER PT J AU Thornton, BF Toohey, DW Avallone, LM Hallar, AG Harder, H Martinez, M Simpas, JB Brune, WH Koike, M Kondo, Y Takegawa, N Anderson, BE Avery, MA AF Thornton, BF Toohey, DW Avallone, LM Hallar, AG Harder, H Martinez, M Simpas, JB Brune, WH Koike, M Kondo, Y Takegawa, N Anderson, BE Avery, MA TI Variability of active chlorine in the lowermost Arctic stratosphere SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID IN-SITU MEASUREMENTS; MIDLATITUDE OZONE LOSS; HETEROGENEOUS CHEMISTRY; TROPOPAUSE REGION; UPPER TROPOSPHERE; POLAR VORTEX; WINTER STRATOSPHERE; REACTIVE NITROGEN; CIRRUS CLOUDS; ICE AB [1] We examine the variability of ClO in the Arctic upper troposphere and lowermost stratosphere (UTLS) during the winter of 1999 - 2000. Data are binned relative to NOy, a species that is a proxy for photochemical age and a photochemical source of NOx. Enhancements in the [ClO]/[Cl-y] ratio relative to values expected from gas-phase chemistry alone were observed throughout the region and were largest in the coldest sampled regions, where T < 208 K. At low NOy values, where particles containing NOy and water were often detected, twilight ClO abundances in the afternoon were nearly a factor of 3 larger than those in the morning. At higher NOy values, where much lower particle surface areas were measured, ClO abundances in morning twilight were somewhat larger than those in the afternoon. These observations are consistent with a daytime mechanism of rapid heterogeneous activation of inorganic chlorine in particle-rich, low-NOy regions, with slower deactivation in relatively particle-poor, higher-NOy regions of the lowermost stratosphere. While the data clearly show widespread chlorine activation, knowledge of the precise value of the [ClO]/[Cl-y] ratio is limited because of the lack of available data on inorganic chlorine species, notably HCl, believed to be the dominant reservoir of inorganic chlorine at these altitudes. C1 Univ Colorado, Program Atmospher & Ocean Sci, Boulder, CO 80309 USA. Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80309 USA. Penn State Univ, Dept Meteorol, University Pk, PA 16802 USA. Univ Tokyo, Grad Sch Sci, Dept Earth & Planetary Sci, Bunkyo Ku, Tokyo 1130033, Japan. Univ Tokyo, Adv Sci & Technol Res Ctr, Meguro Ku, Tokyo 1538904, Japan. NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Thornton, BF (reprint author), Univ Colorado, Program Atmospher & Ocean Sci, Campus Box 311, Boulder, CO 80309 USA. EM brett.thornton@colorado.edu RI Koike, Makoto/F-4366-2011; Toohey, Darin/A-4267-2008; Kondo, Yutaka/D-1459-2012; Hallar, Anna Gannet/I-9104-2012; Harder, Hartwig/L-2511-2014 OI Toohey, Darin/0000-0003-2853-1068; Hallar, Anna Gannet/0000-0001-9972-0056; Harder, Hartwig/0000-0002-6868-714X NR 58 TC 6 Z9 6 U1 0 U2 3 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 NOV 16 PY 2005 VL 110 IS D22 AR D22304 DI 10.1029/2004JD005580 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 988IN UT WOS:000233587300001 ER PT J AU Morales-Cruz, AL Van Keuls, FW Miranda, FA Cabrera, CR AF Morales-Cruz, AL Van Keuls, FW Miranda, FA Cabrera, CR TI Self-assembled monolayers and chemical derivatization of Ba0.5Sr0.5TiO3 thin films: Applications in phase shifter devices SO APPLIED SURFACE SCIENCE LA English DT Article DE self-assembled monolayers; Ba0.5Sr0.5TiO3; coupled microstrip phase shifters; 3-aminopropyltrimethoxysilane; 16-mercaptohexadecanoic acid; 3-mercaptopropyltrimethoxysilane; 3-mercaptopropionic acid; X-ray photoelectron spectroscopy ID TUNABLE MICROWAVE DEVICES; DEPOSITION; GROWTH; MGO AB Thin films of barium strontium titanate (Ba1-xSrx TiO3 (BSTO)) have been used in coupled microstrip phase shifters (CMPS) for possible insertion in satellite and wireless communication platforms primarily because of their high dielectric constant, low loss, large tunability, and good structural stability. In an attempt to improve the figure of merit K (phase shift degrees/ dB of loss) of phase shifters, modification of the metal/BSTO interface of these devices has been done through surface modification of the BSTO layer using a self-assembled monolayer approach. The impact of this nanotechnology promises to reduce RF losses by improving the quality of the metal/BSTO interface. In this study, compounds such as 3-mercapto-propyltrimethoxysilane (MPS), 16-mercaptohexadecanois acid (MHDA) and 3-mercaptopropionic acid (MPA) were used to form the self-assembled monolayers on the BSTO surface. As a result of the previous modification, chemical derivatization of the self-assembled monolayers was done in order to increase the chain length. Chemical derivatization was done using 3-aminopropyltrimethoxysilane (APS) and 16-mercaptohexadecanoic acid. Surface chemical analysis was done to reveal the composition of the derivatization via X-ray photoelectron spectroscopy (XPS) and Fourier Transform Infrared (FT-IR). Low and high frequencies measurements of phase shifters were done in order measure the performance of these devices for insertion in antennas. X-ray photoelectron spectroscopy characterization of modified BSTO thin films with MPS showed a binding energy peak at 162.9 eV, indicative of a possible S-O interaction: sulfur of the mercapto compound, MPS, used to modify the surface with the oxygen site of the BSTO thin film. This interaction is at higher binding energies compared with the thiolate interaction. This behavior is observed with the other mercapto compounds such as: MHDA and MPA. An FT-IR analysis present a band at 780 cm(-1), which is characteristic of an O-S-C stretching and reveals the modification of the BSTO thin film by the coupling of the O of the BSTO with the S of the mercapto compound. All the modification using mercapto compounds is through sulfur to the BSTO thin film. MHDA SAM on BSTO thin film was chemically derivatized using APS shown by XPS and FT-IR. The SAMs modified phase shifters showed an improvement in performance with respect to those phase shifters fabricated with standard methods. (c) 2005 Elsevier B.V. All rights reserved. C1 Univ Puerto Rico Rio Piedras, Dept Chem, San Juan, PR 00931 USA. Ohio Aerosp Inst, Cleveland, OH 44142 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Cabrera, CR (reprint author), Univ Puerto Rico Rio Piedras, Dept Chem, POB 23346, San Juan, PR 00931 USA. EM ccabrera@cnnet.clu.edu OI Cabrera, Carlos/0000-0002-3342-8666 NR 18 TC 5 Z9 5 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-4332 J9 APPL SURF SCI JI Appl. Surf. Sci. PD NOV 15 PY 2005 VL 252 IS 4 BP 981 EP 995 DI 10.1016/j.apsusc.2005.01.152 PG 15 WC Chemistry, Physical; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA 979UL UT WOS:000232970300015 ER PT J AU Engrand, C McKeegan, KD Leshin, LA Herzog, GF Schnabel, C Nyquist, LE Brownlee, DE AF Engrand, C McKeegan, KD Leshin, LA Herzog, GF Schnabel, C Nyquist, LE Brownlee, DE TI Isotopic compositions of oxygen, iron, chromium, and nickel in cosmic spherules: Toward a better comprehension of atmospheric entry heating effects SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID DEEP-SEA SPHERULES; CARBONACEOUS CHONDRITES; ANTARCTIC MICROMETEORITES; ELEMENTAL COMPOSITION; PARENT BODY; METEORITES; OLIVINE; DUST; MG; FRACTIONATION AB Large, correlated, mass-dependent enrichments in the heavier isotopes of 0, Cr, Fe, and Ni are observed in type-I (metal/metal oxide) cosmic spherules collected from the deep sea. Limited intraparticle variability of oxygen isotope abundances, typically < 5 parts per thousand in delta(18)O, indicates good mixing of the melts and Supports the application of the Rayleigh equation for the calculation of fractional evaporative losses during atmospheric entry. Fractional losses for oxygen evaporation from wustite, assuming a starting isotopic composition equal to that of air (delta(18)O = 23.5 parts per thousand; delta(17)O = 11.8 parts per thousand), are in the range 55%-77%, and are systematically smaller than evaporative losses calculated for Fe (69%-85%), Cr (81%-95%), and especially Ni (45%-99%). However, as delta(18)O values increase, fractional losses for oxygen approach those of Fe, Cr, and Ni indicating a shift in the evaporating species from metallic to oxidized forms as the spherules are progressively oxidized during entry heating. The observed unequal fractional losses of 0 and Fe can be reconciled by allowing for a kinetic isotope mass-dependent fractionation of atmospheric oxygen during the oxidation process and/or that some metallic Fe may have undergone Rayleigh evaporation before oxidation began. In situ measurements of oxygen isotopic abundances were also performed in 14 type-S (silicate) cosmic spherules, 13 from the Antarctic ice and one from the deep sea. Additional bulk Fe and Cr isotopic abundances were determined for two type-S deep-sea spherules. The isotopic fractionation of Cr isotopes suggest appreciable evaporative loss of Cr, perhaps as a Sulfide. The oxygen isotopic compositions for the type-S spherules range from delta(18)O = -2 parts per thousand to + 27 parts per thousand. The intraspherule isotopic variations are typically small, similar to 5% relative, except for the less-heated porphyritic spherules which have preserved large isotopic heterogeneities in at least one case. A plot of delta(17)O VS. delta(18)O values for these spherules defines a broad parallelogram bounded at higher values of delta(17)O by the terrestrial fractionation line, and at lower values of delta(17)O by a line parallel to it and anchored near the isotopic composition of delta(18)O = -2.5 parts per thousand and delta(17)O = -5 parts per thousand. Lack of independent evidence for substantial evaporative losses suggests that much of this variation reflects the starting isotopic composition of the precursor materials, which likely resembled CO, CM, or CI chondrites. However, the enrichments in heavy isotopes indicate that some mixing with atmospheric oxygen was probably involved during atmospheric entry for some of the spherules. Isotopic fractionation due to evaporation of incoming grain is not required to explain most of the oxygen isotopic data for type-S spherules. However spherules with barred olivine textures that are thought to have experienced a more intense heating than the porphyritic ones might have undergone some distillation. Two cosmic spherules, one classified as a radial pyroxene type and the other showing a glassy texture, show unfractionated oxygen isotopic abundances. They are probably chondrule fragments that Survived atmospheric entry unmelted. Possible reasons type-I spherules show larger degrees of isotopic fractionation than type-S spherules include: a) the short duration of the heating pulse associated with the high volatile content of the type-S spherule precursors compared to type-I spherules; b) higher evaporation temperatures for at least a refractory portion of the silicates compared to that of iron metal or oxide; c) lower duration of heating of type-S spherules compared to type-I spherules as a consequence of their lower densities. Copyright (c) 2005 Elsevier Ltd. C1 Univ Calif Los Angeles, Dept Earth & Space Sci, Los Angeles, CA 90095 USA. Rutgers State Univ, Dept Chem & Biol Chem, Piscataway, NJ 08854 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Univ Washington, Dept Astron, Seattle, WA 98195 USA. RP Engrand, C (reprint author), Ctr Spectrometrie Nucl & Spectrometrie Masse, Bat 104, F-91405 Orsay, France. EM engrand@csnsm.in2p3.fr RI McKeegan, Kevin/A-4107-2008; UCLA, SIMS/A-1459-2011 OI McKeegan, Kevin/0000-0002-1827-729X; NR 59 TC 34 Z9 34 U1 2 U2 10 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 NOV 15 PY 2005 VL 69 IS 22 BP 5365 EP 5385 DI 10.1016/j.gca.2005.07.002 PG 21 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 999UZ UT WOS:000234417400014 ER PT J AU Kataoka, R Fairfield, DH Sibeck, DG Rastatter, L Fok, MC Nagatsuma, T Ebihara, Y AF Kataoka, R Fairfield, DH Sibeck, DG Rastatter, L Fok, MC Nagatsuma, T Ebihara, Y TI Magnetosheath variations during the storm main phase on 20 November 2003: Evidence for solar wind density control of energy transfer to the magnetosphere SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article AB Energy transfer from the solar wind into the magnetosphere and ionosphere is controlled by the southward magnetic field in the magnetosheath which under normal high Mach number conditions is about four times the solar wind southward field. In a low Mach number regime, however, the magnetosheath compression is diminished by a low solar wind density when the magnetic field remains steady. When magnetic clouds with extremely strong magnetic field cause severe geomagnetic storms under such low Mach number conditions, the density control of the energy transfer is expected to be important in understanding ring current evolution. Here we show evidence for such a density effect using in-situ observation by the GOES and Cluster spacecraft in the magnetosheath during the main phase of the super storm on 20 November 2003. Results from a global magnetohydrodynamic (MHD) simulation with an embedded ring current model also support this density effect. C1 Natl Inst Informat & Commun Technol, Tokyo, Japan. NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Greenbelt, MD 20771 USA. Natl Inst Polar Res, Itabashi Ku, Tokyo 173, Japan. RP Kataoka, R (reprint author), Natl Inst Informat & Commun Technol, Tokyo, Japan. EM ryuho@nict.go.jp RI Sibeck, David/D-4424-2012; Rastaetter, Lutz/D-4715-2012; Fok, Mei-Ching/D-1626-2012; Ebihara, Yusuke/D-1638-2013; OI Rastaetter, Lutz/0000-0002-7343-4147; Ebihara, Yusuke/0000-0002-2293-1557; Nagatsuma, Tsutomu/0000-0002-9334-0738 NR 15 TC 9 Z9 11 U1 0 U2 2 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 NOV 15 PY 2005 VL 32 IS 21 AR L21108 DI 10.1029/2005GL024495 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 988IB UT WOS:000233585700010 ER PT J AU Cooper, JF Khurana, KK AF Cooper, JF Khurana, KK TI Jovian magnetospheric environment science SO ICARUS LA English DT Editorial Material C1 NASA, Goddard Space Flight Ctr, Space Phys Data Facil, Greenbelt, MD 20771 USA. Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90095 USA. RP Cooper, JF (reprint author), NASA, Goddard Space Flight Ctr, Space Phys Data Facil, Code 612-4, Greenbelt, MD 20771 USA. EM john.f.cooper@nasa.gov; kkhurana@igpp.ucla.edu RI Cooper, John/D-4709-2012 NR 5 TC 0 Z9 0 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 NOV 15 PY 2005 VL 178 IS 2 BP 295 EP 296 DI 10.1016/j.icarus.2005.08.004 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 985KM UT WOS:000233376300001 ER PT J AU Pryor, WR Stewart, AIF Esposito, LW McClintock, WE Colwell, JE Jouchoux, AJ Steffl, AJ Shemansky, DE Ajello, JM West, RA Hansen, CJ Tsurutani, BT Kurth, WS Hospodarsky, GB Gurnett, DA Hansen, KC Waite, JH Crary, FJ Young, DT Krupp, N Clarke, JT Grodent, D Dougherty, MK AF Pryor, WR Stewart, AIF Esposito, LW McClintock, WE Colwell, JE Jouchoux, AJ Steffl, AJ Shemansky, DE Ajello, JM West, RA Hansen, CJ Tsurutani, BT Kurth, WS Hospodarsky, GB Gurnett, DA Hansen, KC Waite, JH Crary, FJ Young, DT Krupp, N Clarke, JT Grodent, D Dougherty, MK TI Cassini UVIS observations of Jupiter's auroral variability SO ICARUS LA English DT Article; Proceedings Paper CT Conference on Jovian Magnetospheric Environment Science for the Jupiter Icy Moons Orbiter CY 2003 CL San Francisco, CA SP Amer Geophys Union DE auroras; Jupiter; solar wind; ultraviolet ID SOLAR-WIND CONTROL; IO PLASMA TORUS; RELATIVISTIC ELECTRONS; JOVIAN MAGNETOSPHERE; GALILEO ORBITER; RADIO-BURSTS; EMISSIONS; SPECTROMETER; SPECTROSCOPY; RADIATION AB The Cassini spacecraft Ultraviolet Imaging Spectrograph (UVIS) obtained observations of Jupiter's auroral emissions in H-2 band systems and H Lyman-alpha from day 275 of 2000 (October 1), to day 81 of 2001 (March 22). Much of the globally integrated auroral variability measured with UVIS can be explained simply in terms of the rotation of Jupiter's main auroral arcs with the planet. These arcs were also imaged by the Space Telescope Imaging Spectrograph (STIS) on Hubble Space Telescope (HST). However, several brightening events were seen by UVIS in which the global auroral output increased by a factor of 2-4. These events persisted over a number of hours and in one case can clearly be tied to a large solar coronal mass ejection event. The auroral UV emissions from these bursts also correspond to hectometric radio emission (0.5-16 MHz) increases reported by the Galileo Plasma Wave Spectrometer (PWS) and Cassim Radio and Plasma Wave Spectrometer (RPWS) experiments. In general, the hectometric radio data vary differently with longitude than the UV data because of radio wave beaming effects. The 2 largest events in the UVIS data were on 2000 day 280 (October 6) and on 2000 days 325-326 (November 20-21). The global brightening events on November 20-21 are compared with corresponding data on the interplanetary magnetic field, solar wind conditions, and energetic particle environment. ACE (Advanced Composition Explorer) solar wind data was numerically propagated from the Earth to Jupiter with an MHD code and compared to the observed event. A second class of brief auroral brightening events seen in HST (and probably UVIS) data that last for similar to 2 min is associated with aurora] flares inside the main auroral ovals. On January 8, 2001, from 18:45-19:35 UT UVIS H-2 band emissions from the north polar region varied quasiperiodically. The varying emissions, probably due to amoral flares inside the main auroral oval, are correlated with low-frequency quasiperiodic radio bursts in the 0.6-5 kHz Galileo PWS data. (c) 2005 Elsevier Inc. All rights reserved. C1 Cent Arizona Coll, Coolidge, AZ 85228 USA. Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80309 USA. Univ So Calif, Los Angeles, CA USA. CALTECH, Jet Prop Lab, Pasadena, CA USA. Univ Iowa, Iowa City, IA 52242 USA. Univ Michigan, Ann Arbor, MI 48109 USA. SW Res Inst, San Antonio, TX USA. Max Planck Inst Sonnensyst Forsch, Katlenburg Lindau, Germany. Boston Univ, Boston, MA 02215 USA. Univ Liege, B-4000 Liege, Belgium. UCL, London WC1E 6BT, England. RP Cent Arizona Coll, 8470 N Overfield Rd, Coolidge, AZ 85228 USA. EM wayne_pryor@centralaz.edu RI Hansen, Kenneth/F-3693-2011; Clarke, John/C-8644-2013; OI Hansen, Kenneth/0000-0002-8502-1980; Hospodarsky, George/0000-0001-9200-9878; Kurth, William/0000-0002-5471-6202 NR 62 TC 29 Z9 29 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 NOV 15 PY 2005 VL 178 IS 2 BP 312 EP 326 DI 10.1016/j.icarus.2005.05.021 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 985KM UT WOS:000233376300003 ER PT J AU Ajello, JM Pryor, W Esposito, L Stewart, I McClintock, W Gustin, J Grodent, D Gerard, JC Clarke, JT AF Ajello, JM Pryor, W Esposito, L Stewart, I McClintock, W Gustin, J Grodent, D Gerard, JC Clarke, JT TI The Cassini Campaign observations of the Jupiter aurora by the Ultraviolet Imaging Spectrograph and the Space Telescope Imaging Spectrograph SO ICARUS LA English DT Article; Proceedings Paper CT Conference on Jovian Magnetospheric Environment Science for the Jupiter Icy Moons Orbiter CY 2003 CL San Francisco, CA SP Amer Geophys Union DE spectroscopy; Jupiter magnetosphere; Jupiter atmosphere; ultraviolet observations ID ELECTRON-IMPACT EXCITATION; JOVIAN AURORA; CROSS-SECTIONS; GALILEO ORBITER; SELF-ABSORPTION; H-2; EMISSION; PRECIPITATION; SPECTRUM; SPECTROSCOPY AB We have analyzed the Cassini Ultraviolet Imaging, Spectrometer (UVIS) observations of the Jupiter aurora with an auroral atmosphere two-stream electron transport code. The observations Of Jupiter by UVIS took place during the Cassini Campaign. The Cassini Campaign included Support spectral and imaging observations by the Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph (STIS). A major result for the UVIS observations was the identification of a large color variation between the far ultraviolet (FUV: 1100-1700 angstrom) and extreme ultraviolet (EUV: 800-1100 angstrom) spectral regions. This change probably occurs because of a large variation in the ratio of the soft electron flux (10-3000 eV) responsible for the EUV aurora to the hard electron flux (similar to 15-22 keV) responsible for the FUV aurora. On the basis of this result a new color ratio for integrated intensities for EUV and FUV was defined (4 pi I1550-1620 angstrom/4 pi I (1030-1150 angstrom)) which varied by approximately a factor of 6. The FUV color ratio (4 pi I (1550-1620) angstrom/4 pi (1230-1300) (angstrom)) was note stable with a variation of less than 50% for the observations studied. The medium resolution (0.9 angstrom FWHM, G140M grating) FUV observations (1295-1345 angstrom and 1495-1540 angstrom) by STIS on 13 January 2001, on the other hand, were analyzed by a spectral modeling technique using a recently developed high-spectral resolution model for the electron-excited H-2 rotational lines. The STIS FUV data were analyzed with a model that considered the Lyman band spectrum (B (1) Sigma(+)(u) -> X-1 Sigma(+)(g)) as composed of an allowed direct excitation component (X-1 Sigma(+)(g) B-1 (+)(Sigma u)) and an optically forbidden component (X-1 Sigma(+)(g) -> EF, GK, H (H) over bar,.... (1)Sigma(+)(u) followed by the cascade transition (1)Sigma -> B-1 Sigma(+)(u)). The medium-resolution spectral regions for the Jupiter aurora were carefully chosen to emphasize the cascade component. The ratio of the two components is a direct measurement of the mean secondary electron energy of the aurora. The mean secondary electron energy of the aurora varies between 50 and 200 eV for the polar cap, limb and auroral oval observations. We examine a long time base of Galileo Ultraviolet Spectrometer color ratios from the standard mission (1996-1998) and compare them to Cassini UVIS, HST, and International Ultraviolet Explorer (IUE) observations. (c) 2005 Elsevier Inc. All rights reserved. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Cent Arizona Coll, Casa Grande, AZ 85228 USA. Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80303 USA. Univ Liege, Lab Phys Atmospher & Planetaire, B-4000 Liege, Belgium. Boston Univ, Boston, MA 02215 USA. RP CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. EM jajello@mail.jpl.nasa.gov RI Clarke, John/C-8644-2013; OI GERARD, Jean-Claude/0000-0002-8565-8746 NR 41 TC 19 Z9 19 U1 0 U2 5 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 NOV 15 PY 2005 VL 178 IS 2 BP 327 EP 345 DI 10.1016/j.icarus.2005.01.023 PG 19 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 985KM UT WOS:000233376300004 ER PT J AU Jun, I Garrett, HB Swimm, R Evans, RW Clough, G AF Jun, I Garrett, HB Swimm, R Evans, RW Clough, G TI Statistics of the variations of the high-energy electron population between 7 and 28 jovian radii as measured by the Galileo spacecraft SO ICARUS LA English DT Article; Proceedings Paper CT Conference on Jovian Magnetospheric Environment Science for the Jupiter Icy Moons Orbiter CY 2003 CL San Francisco, CA SP Amer Geophys Union DE Jupiter magnetosphere; Europa; Ganymede; Callisto ID MAGNETIC-FIELD; MAGNETOSPHERE AB Recent measurements of the high-energy, omni-directional electron environment by the Galileo spacecraft Energetic Particle Detector (EPD) have been analyzed in the range from 7 to 28 Jupiter radii. 10-min averages of these data between Jupiter orbit insertion in 1995 to the end of the mission have been analyzed to provide estimates of the electron differential fluxes at 1.5, 2, and 11 MeV in the jovian equatorial plane as a function of radial distance. These data provide a long term picture of the variations in the high-energy electron environment over the similar to 8 years of the Galileo mission. This paper reviews those measurements and the statistics associated with them for the 8 year period. In general, the data variations are well behaved with variations being within a factor of similar to 2 of a median value at a given distance from Jupiter. These results are analyzed in detail and the orbit variations discussed in the context of the overall data set. The results of this analysis of the long-term statistical variations in high-energy electron fluxes are directly applicable to models that estimate the effects of the radiation environment on Jupiter's moons and their atmospheres as they permit estimates of the possible range of radiation effects that might be expected. (c) 2005 Elsevier Inc. All rights reserved. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Govt Serv Inc, Commun L3, Montrose, CA 91020 USA. Gibbel Corp, Montrose, CA 91020 USA. Bates Coll, Lewiston, ME 04240 USA. RP Jun, I (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,Mail Stop 122-107, Pasadena, CA 91109 USA. EM insoo.jun@jpl.nasa.gov NR 9 TC 10 Z9 10 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 NOV 15 PY 2005 VL 178 IS 2 BP 386 EP 394 DI 10.1016/j.icarus.2005.01.022 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 985KM UT WOS:000233376300008 ER PT J AU Elsner, RF Ramsey, BD Waite, JH Rehak, P Johnson, RE Cooper, JF Swartz, DA AF Elsner, RF Ramsey, BD Waite, JH Rehak, P Johnson, RE Cooper, JF Swartz, DA TI X-ray probes of magnetospheric interactions with Jupiter's auroral zones, the Galilean satellites, and the Io plasma torus SO ICARUS LA English DT Article; Proceedings Paper CT Conference on Jovian Magnetospheric Environment Science for the Jupiter Icy Moons Orbiter CY 2003 CL San Francisco, CA SP Amer Geophys Union DE instrumentation; experimental techniques; Jupiter, magnetosphere; Io; Europa; Ganymede; Callisto; aurorae; abundances; impact processes ID INFRARED MAPPING SPECTROMETER; JOVIAN MAGNETOSPHERE; EUROPAS SURFACE; ENERGETIC PARTICLE; SODIUM ATMOSPHERE; EMISSIONS; CALLISTO; OCEAN; SO2; BOMBARDMENT AB Remote observations with the Chandra X-ray Observatory and the XMM-Newton Observatory have shown that the jovian system is a source of X-rays with a rich and complicated structure. The planet's polar aurora] zones and its disk are both powerful sources of X-ray emission. Chandra observations revealed X-ray emission from the to plasma torus and from the Galilean moons Io, Europa, and possibly Ganymede. The emission from the moons is due to bombardment of their surfaces by highly energetic magnetospheric protons, and oxygen and sulfur ions. These ions excite atoms in their surfaces leading to fluorescent X-ray emission lines. These lines are produced against an intense background continuum, including bremsstrahlung radiation from surface interactions of primary magnetospheric and secondary electrons. Although the X-ray emission from the Galilean moons is faint when observed from Earth orbit, an imaging X-ray spectrometer in orbit around one or more of these moons, operating from 200 eV to 8 keV with 150 eV energy resolution, would provide a detailed mapping of the elemental composition in their surfaces. Surface resolution of 40 m for small features could be achieved in a 100-km orbit around one moon while also remotely imaging surfaces of other moons and Jupiter's upper atmosphere at maximum regional resolutions of hundreds of kilometers. Due to its relatively more benign magnetospheric radiation environment, its intrinsic interest as the largest moon in the Solar System, and its mini-magnetosphere, Ganymede would be the ideal orbital location for long-term observational studies of the jovian system. Here we describe the physical processes leading to X-ray emission from the surfaces of Jupiter's moons and the properties required for the technique of imaging X-ray spectroscopy to map the elemental composition of their surfaces, as well as studies of the X-ray emission from the planet's aurora and disk and from the to plasma torus. (c) 2005 Elsevier Inc. All rights reserved. C1 NASA, George C Marshall Space Flight Ctr, Univ Space Res Assoc, Huntsville, AL 35812 USA. Univ Michigan, Dept Atmospher Ocean & Space Sci, Ann Arbor, MI 48109 USA. Brookhaven Natl Lab, Instrumentat Div, Upton, NY 11973 USA. Univ Virginia, Charlottesville, VA 22901 USA. NASA, Goddard Space Flight Ctr, Space Phys Data Facil, Greenbelt, MD 20771 USA. RP NASA, George C Marshall Space Flight Ctr, Univ Space Res Assoc, XD 12, Huntsville, AL 35812 USA. EM ron.elsner@nasa.gov RI Cooper, John/D-4709-2012 NR 74 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 EI 1090-2643 J9 ICARUS JI Icarus PD NOV 15 PY 2005 VL 178 IS 2 BP 417 EP 428 DI 10.1016/j.icarus.2005.06.006 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 985KM UT WOS:000233376300011 ER PT J AU Mennesson, B Leger, A Ollivier, M AF Mennesson, B Leger, A Ollivier, M TI Direct detection and characterization of extrasolar planets: The Mariotti space interferometer SO ICARUS LA English DT Article; Proceedings Paper CT Conference on Jovian Magnetospheric Environment Science for the Jupiter Icy Moons Orbiter CY 2003 CL San Francisco, CA SP Amer Geophys Union DE extra-solar planetary systems; instrumentation; infrared observations; zodiacal light; atmospheric spectroscopy ID NON-SOLAR PLANETS; NULLING INTERFEROMETER; ARRAY CONFIGURATIONS; PRIMITIVE LIFE; EARTH; SEARCH; SIGNATURE; FINDER; DUST; RING AB Space infrared nulling interferometry has been identified as one of the most promising techniques for direct detection of Earthlike extrasolar planets and spectroscopic analysis of their atmospheres in the near future. After a review of various nulling interferometer schemes, we introduce the concept of internal modulation. As an illustration, we describe a two-dimensional array of telescopes that provides full internal modulation capabilities: the Mariotti space interferometer. It consists of six free-flying telescopes positioned on the sides of an equilateral triangle and grouped into three nulling interferometers. Their nulled outputs are suitably phase-shifted with respect to each other, coherently recombined, and detected. The phase shifts applied between the nullers are periodically changed, providing signal modulation at a frequency that can be selected to minimize instrumental and background noise. The frequency upper limit is set by the read-out noise of the detectors, and turns out to be 10(-1)-10(-2) Hz for Currently available Si:As BIB devices. This "fast" signal modulation allows much better monitoring of the background and detector drifts than when one relies solely on the external modulation provided by the slow rotation of the whole interferometer (at typical frequencies of 3 x 10(-4)-3 x 10(-5) Hz). Mariotti internal modulation, also known as "phase chopping," thus appears as a major step toward the feasibility of the Darwin and TPF space missions. (c) 2005 Elsevier Inc. All rights reserved. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Paris 11, IAS, F-91405 Orsay, France. RP Mennesson, B (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM bmenness@huey.jpl.nasa.gov NR 44 TC 20 Z9 20 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 NOV 15 PY 2005 VL 178 IS 2 BP 570 EP 588 DI 10.1016/j.icarus.2005.05.012 PG 19 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 985KM UT WOS:000233376300021 ER PT J AU Li, Q Yang, S Kousky, VE Higgins, RW Lau, KM Xie, P AF Li, Q Yang, S Kousky, VE Higgins, RW Lau, KM Xie, P TI Features of cross-pacific climate shown in the variability of China and us precipitation SO INTERNATIONAL JOURNAL OF CLIMATOLOGY LA English DT Article DE cross-Pacific climate; China and US precipitation; comparison; teleconnection ID SEA-SURFACE TEMPERATURE; ASIAN SUMMER MONSOON; TROPICAL WESTERN PACIFIC; NORTHERN-HEMISPHERE; EAST-ASIA; INTERANNUAL VARIABILITY; SOUTHERN OSCILLATION; UNITED-STATES; TELECONNECTION PATTERNS; EXTREME EVENTS AB In this study, we have analyzed the climate features of China and the United States with a focus on the differences, similarities, connectivity, and predictability of precipitation and the relationships between precipitation and large-scale patterns of natural variability. China precipitation is characterized by large seasonality, with a maximum in summer and a minimum in winter. The seasonality of precipitation shows an increasing linear tendency in northwest China, with a change of about 20% from 1901 to 1998. A relatively weaker increasing tendency also appears in the Big Bend of Yellow River (BBYR) and the Tibetan Plateau, while southwest China experiences a decreasing tendency. Furthermore, the seasonality in the BBYR shows particularly significant interdecadal variability, while that of southern and eastern China has decreased slightly in the recent decades. Compared to China, the United States as a whole has less precipitation in summer but more precipitation in other seasons. Here, the seasonality of precipitation is only about 24% of that in China. The annual mean precipitation is 64.1 mm per month in the United States, compared to 54.6 mm per month in China. The seasonality of precipitation exhibits a decreasing tendency in the southeast, Pacific Northwest, and Gulf Coast and an increasing tendency in the Great Lakes. The seasonality in the Great Plains exhibits large interdecadal variability. The long-term variations of precipitation are highly seasonally dependent. In summer, a decreasing trend is observed in north China and an increasing trend is found in eastern-central China. However, these trends are almost opposite in spring. In addition, the fall precipitation decreases with time nearly everywhere in China except for the middle and lower reaches of the Yangtze River Valley. The long-term variations of precipitation are highly seasonally dependent. In summer, a decreasing trend is observed in north China and an increasing trend is found in eastern-central China. However, these trends are almost opposite in spring. In addition, the fall precipitation decreases with time nearly everywhere in China except for the middle and lower reaches of the Yangtze River Valley. Results also indicate that the El Nino/Southern Oscillation (ENSO), the Arctic Oscillation (AO), the North Atlantic Oscillation (NAO), the Pacific Decadal Oscillation (PDO), and the North Pacific (NP) fluctuation affect strongly the variations of China and US precipitation. Although these influences vary with regions and seasons, we in particular emphasize the importance of AO and NAO for China precipitation and NP and PDO for US precipitation. In fall, ENSO and PDO are the two phenomena that influence predominantly precipitation variability in both China and the United States We also identify the common phenomena that influence China and US regional precipitation and provide a better understanding of the physical mechanism for precipitation variability through the associated changes in atmospheric and oceanic conditions. Furthermore, we develop a linear regression model, based on multiple regression method by combining the regionally and seasonally varying impacts, to increase the skill of precipitation prediction. Copyright (c) 2005 Royal Meteorological Society. C1 NOAA, Climate Predict Ctr, NCEP, NWS, Camp Springs, MD 20746 USA. NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. RP Yang, S (reprint author), NOAA, Climate Predict Ctr, NCEP, NWS, 5200 Auth Rd,Room 605, Camp Springs, MD 20746 USA. EM Song.Yang@noaa.gov RI Yang, Song/B-4952-2009; Lau, William /E-1510-2012 OI Lau, William /0000-0002-3587-3691 NR 76 TC 39 Z9 41 U1 4 U2 16 PU JOHN WILEY & SONS LTD PI CHICHESTER PA THE ATRIUM, SOUTHERN GATE, CHICHESTER PO19 8SQ, W SUSSEX, ENGLAND SN 0899-8418 J9 INT J CLIMATOL JI Int. J. Climatol. PD NOV 15 PY 2005 VL 25 IS 13 BP 1675 EP 1696 DI 10.1002/joc.1271 PG 22 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 982TT UT WOS:000233185200001 ER PT J AU Berg, AA Famiglietti, JS Rodell, M Reichle, RH Jambor, U Holl, SL Houser, PR AF Berg, AA Famiglietti, JS Rodell, M Reichle, RH Jambor, U Holl, SL Houser, PR TI Development of a hydrometeorological forcing data set for global soil moisture estimation SO INTERNATIONAL JOURNAL OF CLIMATOLOGY LA English DT Article DE soil moisture; hydrometeorological forcing; land surface modeling; reanalysis ID DATA ASSIMILATION SYSTEM; LAND-SURFACE INTERACTION; MISSISSIPPI RIVER-BASIN; 1987 FIFE DATA; ECMWF REANALYSIS; WATER-BALANCE; SATELLITE-OBSERVATIONS; NCEP/NCAR REANALYSIS; WETNESS PROJECT; ENERGY BUDGETS AB Off-line land surface modeling simulations require accurate meteorological forcing with consistent spatial and temporal resolutions. Although reanalysis products present an attractive data source for these types of applications, bias to many of the reanalysis fields limits their use for hydrological modeling. In this study, we develop a global 0.5 degrees forcing data sets for the time period 1979-1993 on a 6-hourly time step through application of a bias correction scheme to reanalysis products. We then use this forcing data to drive a land surface model for global estimation of soil moisture and other hydrological states and fluxes. The simulated soil moisture estimates are compared to in situ measurements, satellite observations and to a modeled data set of root zone soil moisture produced within a separate land surface model, using a different data set of hydrometeorological forcing. In general, there is good agreement between anomalies in modeled and observed (in situ) root zone soil moisture. Similarly, for the surface soil wetness state, modeled estimates and satellite observations are in general statistical agreement; however, correlations decline with increasing vegetation amount. Comparisons to a modeled data set of soil moisture also demonstrates that both simulations present estimates that are well correlated for the soil moisture in the anomaly time series, despite being derived from different land surface models, using different data sources for meteorological forcing, and with different specifications of the land surfaces properties. Copyright (c) 2005 Royal Meteorological Society. C1 Univ Guelph, Dept Geog, Guelph, ON N1G 2W1, Canada. Univ Calif Irvine, Dept Earth Syst Sci, Irvine, CA USA. NASA, Goddard Space Flight Ctr, Hydrol Sci Branch, Greenbelt, MD 20771 USA. Univ Maryland, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21201 USA. NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Greenbelt, MD 20771 USA. RP Berg, AA (reprint author), Univ Guelph, Dept Geog, Guelph, ON N1G 2W1, Canada. EM aberg@uoguelph.ca RI Reichle, Rolf/E-1419-2012; Rodell, Matthew/E-4946-2012; Houser, Paul/J-9515-2013 OI Rodell, Matthew/0000-0003-0106-7437; Houser, Paul/0000-0002-2991-0441 NR 67 TC 31 Z9 31 U1 0 U2 4 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0899-8418 EI 1097-0088 J9 INT J CLIMATOL JI Int. J. Climatol. PD NOV 15 PY 2005 VL 25 IS 13 BP 1697 EP 1714 DI 10.1002/joc.1203 PG 18 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 982TT UT WOS:000233185200002 ER PT J AU Shukla, S Zhang, P Cho, HJ Rahman, Z Drake, C Seal, S Craciun, V Ludwig, L AF Shukla, S Zhang, P Cho, HJ Rahman, Z Drake, C Seal, S Craciun, V Ludwig, L TI Hydrogen-discriminating nanocrystalline doped-tin-oxide room-temperature microsensor SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID GAS-SENSING PROPERTIES; THIN-FILM; SENSOR; CO; SNO2; SENSITIVITY; SELECTIVITY; OXYGEN; PD AB Highly hydrogen (H-2)-selective [relative to carbon monoxide (CO)] sensor, operating at room temperature, has been fabricated using the micronanointegration approach involving the deposition of the nanocrystalline indium oxide (In2O3)-doped tin oxide (SnO2) thin film on microelectromechanical systems device. The present microsensor exhibits high room-temperature sensitivity towards H-2 (S=12 700); however, it is insensitive to CO at room temperature. In view of the different gas selectivity mechanisms proposed in the literature, it is deduced that the In2O3 doping, the presence of InSn4 phase, the low operating temperature (room temperature), the mesostructure, the small sizes of H-2 and H2O molecules, the bulky intermediate and final reaction products for CO, and the electrode placement at the bottom are the critical parameters, which significantly contribute to the high room-temperature H-2 selectivity of the present microsensor over CO. The constitutive equation for the gas sensitivity of the semiconductor oxide thin-film sensor, proposed recently by the authors, has been modified to qualitatively explain the observed H-2 selectivity behavior. (c) 2005 American Institute of Physics. C1 Univ Cent Florida, Surface Engn & Nanotechnol Facil, Adv Mat Proc & Anal Ctr, Orlando, FL 32816 USA. Univ Cent Florida, Mech Mat Aerosp Engn Dept, Orlando, FL 32816 USA. Univ Florida, Gainesville, FL 32611 USA. NASA, Elect & Data Acquisit Lab, Kennedy Space Ctr, Kennedy Space Ctr, FL 32899 USA. RP Seal, S (reprint author), Univ Cent Florida, Surface Engn & Nanotechnol Facil, Adv Mat Proc & Anal Ctr, Engn 381,400 Cent Florida Blvd, Orlando, FL 32816 USA. EM sshukla@ucf.edu; sseal@mail.ucf.edu RI Craciun, Valentin/C-4789-2011; OI Shukla, Satyajit/0000-0002-7947-8095 NR 40 TC 16 Z9 16 U1 1 U2 6 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD NOV 15 PY 2005 VL 98 IS 10 AR 104306 DI 10.1063/1.2132095 PG 15 WC Physics, Applied SC Physics GA 988LL UT WOS:000233602600066 ER PT J AU Wang, DY AF Wang, DY TI An eight-degree-of-freedom quantum dynamics study for the H-2+C2H system SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID RATE-CONSTANT MEASUREMENTS; DIMENSIONALITY CALCULATIONS; REDUCED DIMENSIONALITY; TEMPERATURE-DEPENDENCE; REACTIVE SCATTERING; C2H; PHOTOCHEMISTRY; ATMOSPHERE; ACETYLENE; STATE AB An eight-degree-of-freedom (8DOF) time-dependent wave-packet approach has been developed to study the H-2+C2H -> H+C2H2 reaction system. The 8DOF model is obtained by fixing one of the Jacobi torsion angle in the nine-degree-of-freedom AB+CDE reaction system. This study is an extension of the previous seven-degree-of-freedom (7DOF) computation [J. Chem. Phys. 119, 12057 (2003)] of this reaction system. This study shows that vibrational excitations of H-2 enhance the reaction probability, whereas the stretching vibrational excitations of C2H have only a small effect on the reactivity. Furthermore, the bending excitation of C2H, compared to the ground-state reaction probability, hinders the reactivity. A comparison of the rate constant between the 7DOF calculation and the present 8DOF results has been made. The theoretical and experimental results agree with each other very well when the present 8DOF results are adjusted to account for the lower transition state barrier heights found in recent ab initio calculations. C1 NASA, Ames Res Ctr, Eloret, Moffett Field, CA 94035 USA. RP Wang, DY (reprint author), NASA, Ames Res Ctr, Eloret, MS T27B-1, Moffett Field, CA 94035 USA. EM dywang@nas.nasa.gov NR 44 TC 22 Z9 22 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 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD NOV 15 PY 2005 VL 123 IS 19 AR 194302 DI 10.1063/1.2122707 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 985CH UT WOS:000233353200014 PM 16321083 ER PT J AU Huang, WH Day, DE Ray, CS Kim, CW AF Huang, WH Day, DE Ray, CS Kim, CW TI High temperature properties of an iron phosphate melt containing high chrome nuclear waste SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article ID GLASSES AB Iron phosphate glasses are of interest for immobilizing high level nuclear waste (HLW). The high temperature viscosity and AC electrical conductivity of an iron phosphate melt containing 2.8 mass% chrome oxide were investigated in this work. The viscosity of this melt varied from 10 to 50 poise from 1350 to 1150 degrees C, respectively, while the activation energy for viscous flow was 82 and 126 kJ/mol during heating and cooling the melt, respectively. The viscosity of the melt at 1250 degrees C increased with time due to the reduction of Fe3+ to Fe2+. The AC electrical conductivity of the melt varied from 45 to 65 S/m at 1050 and 1350 degrees C, respectively. The activation energy for AC electrical conductivity was 28 and 18 kJ/mol during heating and cooling, respectively. The weight loss rate of the melt at 1250 degrees C after 20 h was only 5 x 10(-4) g/cm(2)/h. (c) 2005 Elsevier B.V. All rights reserved. C1 Univ Missouri, Grad Ctr Mat Res, Rolla, MO 65409 USA. Tongji Univ, Shanghai 200092, Peoples R China. NASA, MSFC, Huntsville, AL 35812 USA. RP Huang, WH (reprint author), Univ Missouri, Grad Ctr Mat Res, Rolla, MO 65409 USA. EM huangwe@umr.edu NR 7 TC 22 Z9 24 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD NOV 15 PY 2005 VL 346 IS 2-3 BP 298 EP 305 DI 10.1016/j.jnucmat.2005.07.004 PG 8 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 982IX UT WOS:000233152400020 ER PT J AU McLachlan, DS Chiteme, C Park, C Wise, KE Lowther, SE Lillehei, PT Siochi, EJ Harrison, JS AF McLachlan, DS Chiteme, C Park, C Wise, KE Lowther, SE Lillehei, PT Siochi, EJ Harrison, JS TI AC and DC percolative conductivity of single wall carbon nanotube polymer composites SO JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS LA English DT Article DE carbon nanotube; conductivity; multifunctionality; nanocomposite; percolation; SWNT ID METAL-INSULATOR SYSTEMS; CONTINUUM-PERCOLATION; PHENOMENOLOGICAL EQUATION; CRITICAL-POINT; THRESHOLD; MEDIA; POLYIMIDE; EXPONENTS; UNIVERSALITY; TEMPERATURE AB The equations needed to correctly interpret both AC and DC conductivity results of single wall carbon nanotube (SWNT) polymer composites and the scaling of these results onto a single master curve are presented. Brief discussions on the factors that determine the critical volume fraction (phi(c)) and the percolation exponent (t) are also given. The results for a series of SWNT-polyimide composites are presented and the parameters obtained from fitting these results are discussed. The critical volume fraction for electrical percolation of the present composite was about 0.0005. Results obtained from previous work on SWNT (MWNT)-polymer composites and other percolation systems and the modeling (interpretation) of these results are also discussed and compared. (c) 2005 Wiley Periodicals, Inc. C1 Natl Inst Aerosp, Hampton, VA USA. Univ Witwatersrand, Sch Phys, Johannesburg, South Africa. NASA, Langley Res Ctr, Adv Mat & Proc Branch, Hampton, VA 23665 USA. RP Park, C (reprint author), Natl Inst Aerosp, Hampton, VA USA. EM c.park@larc.nasa.gov RI Lillehei, Peter/C-9196-2009 OI Lillehei, Peter/0000-0001-8183-9980 NR 41 TC 139 Z9 140 U1 1 U2 29 PU JOHN WILEY & SONS INC PI HOBOKEN PA 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0887-6266 J9 J POLYM SCI POL PHYS JI J. Polym. Sci. Pt. B-Polym. Phys. PD NOV 15 PY 2005 VL 43 IS 22 BP 3273 EP 3287 DI 10.1002/polb.20597 PG 15 WC Polymer Science SC Polymer Science GA 979OB UT WOS:000232953600014 ER PT J AU Matsko, AB Savchenkov, AA Maleki, L AF Matsko, AB Savchenkov, AA Maleki, L TI Vertically coupled whispering-gallery-mode resonator waveguide SO OPTICS LETTERS LA English DT Article AB We theoretically describe a novel configuration of a vertically coupled whispering-gallery-mode resonator waveguide. The waveguide is formed as a chain of doughnut-shaped low-contrast ripples on the surface of a vertical cylinder made from an optically transparent material. One can manipulate the properties of the waveguide by changing the shape of the resonators and the separation distance between them. Application of the structure as an optical delay line is discussed. (c) 2005 Optical Society of America. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Matsko, AB (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Andry.Matsko@jpl.nasa.gov RI Matsko, Andrey/A-1272-2007 NR 6 TC 16 Z9 17 U1 0 U2 5 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD NOV 15 PY 2005 VL 30 IS 22 BP 3066 EP 3068 DI 10.1364/OL.30.003066 PG 3 WC Optics SC Optics GA 983UY UT WOS:000233258800032 PM 16315723 ER PT J AU Steissberg, TE Hook, SJ Schladow, SG AF Steissberg, TE Hook, SJ Schladow, SG TI Characterizing partial upwellings and surface circulation at Lake Tahoe, California-Nevada, USA with thermal infrared images SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE partial upwelling; surface currents; circulation; thermal infrared; ASTER; MODIS; Landsat ETM; clarity; water quality; Lake Tahoe ID NUTRIENT FLUXES; SHEAR-STRESS; MONO LAKE; TRANSPORT; MODIS; WATER AB Thermal infrared data from recently launched satellite instruments provide an opportunity to address key scientific questions and develop new applications, which could not be addressed or developed with data from earlier instruments. The satellite instruments that provide these data include ASTER, Landsat ETM+, and MODIS, and this study demonstrates bow data from them can be used to map upwelling and circulation associated with the transport of heat, solutes, and particles in lakes. Upwelling in a density-stratified water body such as a lake or reservoir results from a surface wind stress being balanced by a horizontal pressure gradient, causing denser water to rise at the upwind lake boundary. Upwellings are considered partial when intermediate-depth water reaches the surface and total when bottom water surfaces. Upwellings are an important part of ecosystem functioning, since they transport nutrients from deeper in the lake, where they accumulate, to the surface layer, where they facilitate phytoplankton growth. Thermal infrared images acquired by ASTER, ETM+, and MODIS can be used to observe partial upwelling events in lakes and provide insight into their spatial variability and horizontal distribution, information totally lacking from conventional in situ measurements. At Lake Tahoe, partial upwellings were found to occur every few days throughout the spring and summer, transporting water from 10-30 in below the surface to the surface layer. They commonly display a jet-like appearance, traveling from the upwind to the downwind side of the lake, with current speeds of 12-17 cm/s. Partial upwellings were found to generally decrease lake clarity, although deeper upwelling events can increase clarity. Sinking zones, other convergence areas, and divergence areas were also observed. The temperature variability associated with upwelling, which could be clearly mapped in the thermal infrared satellite images, illustrates the advantage of synoptic thermal infrared satellite measurements over in situ point measurements alone for detecting upwelling events, since, depending on location, an in situ instrument might not capture an upwelling event. The spatial information conveyed by the synoptic satellite measurements can be used to help improve monitoring of the clarity and general water quality of Lake Tahoe. (C) 2005 Elsevier Inc. All rights reserved. C1 Univ Calif Davis, Dept Civil & Environm Engn, Davis, CA 95616 USA. CALTECH, Jet Prop Lab, Pasadena, CA USA. Univ Calif Davis, Tahoe Environm Res Ctr, Davis, CA 95616 USA. RP Steissberg, TE (reprint author), Univ Calif Davis, Dept Civil & Environm Engn, Davis, CA 95616 USA. EM tsteissberg@ucdavis.edu NR 27 TC 25 Z9 26 U1 1 U2 5 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 NOV 15 PY 2005 VL 99 IS 1-2 BP 2 EP 15 DI 10.1016/j.rse.2005.06.011 PG 14 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 984EV UT WOS:000233286200002 ER PT J AU Stefanov, WL Netzband, M AF Stefanov, WL Netzband, M TI Assessment of ASTER land cover and MODIS NDVI data at multiple scales for ecological characterization of an and urban center SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE urban ecology; scale; land cover classification; ASTER; MODIS; landscape metrics; NDVI ID REMOTELY-SENSED DATA; CLASSIFICATION; RESOLUTION; AREAS; PRODUCTS; IMAGERY; REFLECTANCE; INFORMATION; ALGORITHMS; INDICATORS AB Study of the detailed structure and ecological functioning of urban and peri-urban systems is intensifying due to increasing concentration of the human population into urban centers. Much of this increase is expected to occur in semiarid to and cites. Data from new high spatial, temporal, and spectral resolution satellite-based sensors promise to increase our understanding of global urban ecological and climatic processes and improve city and land planning capabilities. Two of these sensors, the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and the Moderate Resolution Imaging Spectroradiometer (MODIS), provide an opportunity to compare urban spatial structure (distribution and configuration of discrete land cover/land use classes on the landscape) with contemporaneous measurements of surface biophysical composition at a variety of spatial and temporal scales. Such combined measurements are useful for modeling changes to urban climate, hydrology.. and biogeochemical cycles caused by modification of the landscape. We compare gridded landscape metrics derived front expert system land cover classification of ASTER to corresponding MODIS NDVI data at scales of 250 m/pixel, 500 m/pixel, and 1 km/pixel in order to determine which of these scales is optimal for monitoring of urban biophysical processes and landscape structure change. Weak positive and negative correlations between NDVI and landscape structure were observed at all three spatial scales for the metrics Class Area, Mean Patch Size, Edge Density, and Interspersion/Juxtaposition Index. (C) 2005 Elsevier Inc. All rights reserved. C1 NASA, Image Sci & Anal Lab, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Arizona State Univ, Int Inst Sustainabil, Tempe, AZ 85287 USA. RP Stefanov, WL (reprint author), NASA, Image Sci & Anal Lab, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. EM william.l.stefanov1@jsc.nasa.gov NR 74 TC 48 Z9 54 U1 4 U2 26 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 NOV 15 PY 2005 VL 99 IS 1-2 BP 31 EP 43 DI 10.1016/j.rse.2005.04.024 PG 13 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 984EV UT WOS:000233286200004 ER PT J AU Pieri, D Abrams, M AF Pieri, D Abrams, M TI ASTER observations of thermal anomalies preceding the April 2003 eruption of Chikurachki volcano, Kurile Islands, Russia SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE Chikurachki volcano; Kurile islands; TIR; eruption precursor; ASTER; meltwater ID KAMCHATKA REGION; ACTIVE VOLCANOS; LASCAR VOLCANO; CAMPI-FLEGREI; REAL-TIME; TEMPERATURE; IMAGES; PREDICTION; CALIFORNIA; FEATURES AB Chikurachki volcano (Northern Kurile Islands Chain, Paramushir Island 50 degrees 20'N, 155 degrees 27'E; elevation 1816 m, stratovolcano) has been in a state of unrest for over twenty years. Its most recent eruption that began in April 2003 was preceded by an eruption between January and May 2002. Thermal infrared images from the Japanese-United States' Advanced Spaceborne Thermal Emission and Reflection radiometer (ASTER-5 TIR channels, 8-12 mu m, 90 m/pixel, Noise Equivalent Delta Temperature [NE Delta T] similar to 0.1-0.3 K; onboard the U.S. National Aeronautics and Space Administration's Terra polar-orbiting spacecraft) of a snow-covered Chikurachki Volcano taken in January 2003 show muted evidence of thermal activity. ASTER thermal infrared (TIR) images from February 2003, however, indicate warmer areas within the summit crater. Average whole-pixel temperatures of adjacent summit slopes are in the range of 250-252 K, while many summit-crater whole pixel temperatures are similar to 2-6 K greater. A two component Planck solution for the warmer pixels yields a solution of 275-277 K for 10-15% of the Chikurachki summit crater and 285-295 K for 25-35% of a prominent "botspot" on its flank. An interpretation of this enhanced pre-eruption beat flow is the presence of surface melt water. The detection in ASTER data of such subtle precursory heat-flow enhancement, even retrospectively, raises important issues for remote monitoring of "dormant" snow-capped volcanoes, especially those that threaten nearby populations, like Mt. Rainier. (C) 2005 Elsevier Inc. All rights reserved. C1 CALTECH, Jet Prop Lab, Div Earth & Space Sci, Pasadena, CA 91109 USA. RP Pieri, D (reprint author), CALTECH, Jet Prop Lab, Div Earth & Space Sci, Pasadena, CA 91109 USA. EM dave.pieri@jpl.nasa.gov NR 53 TC 41 Z9 41 U1 3 U2 8 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 NOV 15 PY 2005 VL 99 IS 1-2 BP 84 EP 94 DI 10.1016/j.rse.2005.06.012 PG 11 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 984EV UT WOS:000233286200009 ER PT J AU Vaughan, RG Hook, SJ Calvin, WM Taranik, JV AF Vaughan, RG Hook, SJ Calvin, WM Taranik, JV TI Surface mineral mapping at Steamboat Springs, Nevada, USA, with multi-wavelength thermal infrared images SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE thermal infrared; multispectral; hyperspectral; emissivity; mineral mapping; geothermal exploration ID REFLECTION RADIOMETER ASTER; SCANNER TIMS DATA; MULTISPECTRAL SCANNER; DEATH-VALLEY; ATMOSPHERIC COMPENSATION; EMISSION-SPECTROSCOPY; HYPERSPECTRAL DATA; CALIFORNIA; AIRBORNE; TEMPERATURE AB The purpose of this study was to evaluate the use of airborne multispectral and hyperspectral thermal infrared (TIR) image data for mapping surface minerals characteristic of active geothermal systems. TIR image data from the MASTER multispectral spectrometer and the SEBASS hyperspectral spectrometer were acquired over Steamboat Springs, Nevada, USA, in September 1999. Spectral emissivity information was extracted from the data and used to generate mineral maps. Using the MASTER data it was possible to map the extent of the active geothermal area as well as silica-rich vs. clay-rich areas. Using the SEBASS data the same areas could be mapped and additionally the presence of several minerals, including opal, quartz, alunite, anorthite, albite, and kaolinite could be identified. The SEBASS data also detected previously unidentified hydrous sulfate minerals (tamarugite and alunogen) forming around active fumaroles. Laboratory spectral data and XRD analyses of field samples confirmed the dominant mineral phases identified remotely. The airborne, field and laboratory data together with temperature anomaly and fumarole location data from other studies were synthesized and linked to the surface geology to determine the diagnostic surface mineral expression that could be mapped with TIR remotely sensed data for future exploration for similar geothermal systems. Opaline sinter deposits are the most diagnostic surface expression of hot spring activity at Steamboat Springs because they represent areas of the recent geyser activity. The differentiation between opal and chalcedony deposits and the identification of hydrous sulfate minerals forming around active fumaroles are also important because chalcedony represents ancient sinter deposits and hydrous sulfate minerals indicate locations of fumaroles that may be venting diffusely with no geyser activity. The surface expression of the geothermal system at Steamboat Springs is small, which emphasizes the need for high spatial resolution airborne imagers. The 90-m pixels of ASTER TIR data over the same area were only capable of resolving the area of past and recent sinter deposits together. MASTER multispectral TIR data covered the entire area (similar to 12 km(2)) at 5-m spatial resolution and were capable of defining the extent of the sinter deposits and zones of hydrothermally altered rocks. The SEBASS image swath was too narrow (256 in) to add significant spatial information to the overall map, but the high spectral content identified several important minerals related to the local geology and the mineralogic surface expression of the geothermal system. (C) 2005 Elsevier Inc. All rights reserved. C1 Univ Nevada, Dept Geol Sci, Reno, NV 89557 USA. CALTECH, Jet Prop Lab, Pasadena, CA USA. RP Univ Nevada, Dept Geol Sci, Reno, NV 89557 USA. EM greg.vaughan@jpl.nasa.gov NR 61 TC 67 Z9 75 U1 2 U2 15 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 NOV 15 PY 2005 VL 99 IS 1-2 BP 140 EP 158 DI 10.1016/j.rse.2005.04.030 PG 19 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 984EV UT WOS:000233286200013 ER PT J AU Kargel, JS Abrams, MJ Bishop, MP Bush, A Hamilton, G Jiskoot, H Kaab, A Kieffer, HH Lee, EM Paul, F Rau, F Raup, B Shroder, JF Soltesz, D Stainforth, D Stearns, L Wessels, R AF Kargel, JS Abrams, MJ Bishop, MP Bush, A Hamilton, G Jiskoot, H Kaab, A Kieffer, HH Lee, EM Paul, F Rau, F Raup, B Shroder, JF Soltesz, D Stainforth, D Stearns, L Wessels, R TI Multispectral imaging contributions to global land ice measurements from space SO REMOTE SENSING OF ENVIRONMENT LA English DT Review DE ASTER; glacier monitoring; cryosphere; GLIMS; Glacier Land Ice Measurements from Space ID SWISS GLACIER INVENTORY; SURGE-TYPE GLACIERS; CLIMATE-CHANGE; MASS-BALANCE; ASTER DATA; SATELLITE IMAGERY; WEST ANTARCTICA; GREENHOUSE-GAS; SHELF COLLAPSE; GREENLAND AB Global Land Ice Measurements from Space (GLIMS) is an international consortium established to acquire satellite images of the world's glaciers.. analyse them for glacier extent and changes, and assess change data for causes and implications for people and the environment. Although GLIMS is making use of multiple remote-sensing systems, ASTER (Advanced Spaceborne Thermal Emission and reflection Radiometer) is optimized for many needed observations, including mapping of glacier boundaries and material facies, and tracking of surface dynamics., such as flow vector fields and supraglacial lake development. Software development by GLIMS is geared toward mapping clean-ice and debris-covered glaciers; terrain classification emphasizing snow, ice, water, and admixtures of ice with rock debris; multitemporal change analysis, visualization of images and derived data; and interpretation and archiving of derived data. A global glacier database has been designed at the National Snow and Ice Data Center (NSIDC, Boulder, Colorado); parameters are compatible with and expanded from those of the World Glacier Inventory (WGI). These technology efforts are summarized here, but will be presented in detail elsewhere. Our presentation here pertains to one broad question: How can ASTER and other satellite multispectral data be used to map, monitor, and characterize the state and dynamics of glaciers and to understand their responses to 20th and 21st century climate change? Our sampled results are not yet glaciologically or climatically representative. Our early results, while indicating complexity, are generally consistent with the glaciology community's conclusion that climate change is spurring glacier responses around the world (mainly retreat). Whether individual glaciers are advancing or retreating, the aggregate average of glacier change must be climatic in origin, as nonclimatic variations average out. We have discerned regional spatial patterns in glaciological response behavior; these patterns are best attributed to climate-change variability and to regional differences in glacier size and response times. In many cases, glacier length changes under-represent the magnitude of glacier ablation, because thinning (sometimes without immediate length changes) is also important. An expanded systematic, uniform analysis of many more glaciers is needed to isolate the glacier response components due to climatic and nonclimatic perturbations, to produce quantitative measures of regional variation in glacier changes, and to predict future regional glacier trends relevant to water resources, glaciological hazards, and global sea level. This comprehensive assessment (to be completed in stages) is expected to lend a critically needed filter to identify successful climate models that explain recent glacier changes and change patterns (and hence, are apt to describe future changes) and to eliminate unsuccessful models. (C) 2005 Elsevier lnc. All rights reserved. C1 Univ Arizona, Tucson, AZ 85721 USA. CALTECH, Jet Prop Lab, Pasadena, CA USA. Univ Nebraska, Omaha, NE 68182 USA. Univ Alberta, Dept Earth & Atmospher Sci, Edmonton, AB T6G 2E3, Canada. Univ Maine, Climate Change Inst, Orono, ME 04469 USA. Univ Lethbridge, Dept Geog, Lethbridge, AB T1K 3M4, Canada. Univ Zurich, Dept Geog, Glaciol & Geomorphodynam Grp, CH-8057 Zurich, Switzerland. Celestial Reasonings, Carson City, NV USA. Univ Freiburg, Inst Phys Geog, D-7800 Freiburg, Germany. Univ Colorado, Natl Snow & Ice Data Ctr, Boulder, CO 80309 USA. Univ Oxford, Oxford, England. US Geol Survey, Alaska Volcano Observ, Anchorage, AK USA. RP Kargel, JS (reprint author), Univ Arizona, Tucson, AZ 85721 USA. EM kargel@hwr.arizona.edu RI Hamilton, Gordon/G-1679-2011; Kaab, Andreas/A-3607-2012 NR 152 TC 137 Z9 145 U1 8 U2 93 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 NOV 15 PY 2005 VL 99 IS 1-2 BP 187 EP 219 DI 10.1016/j.rse.2005.07.004 PG 33 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 984EV UT WOS:000233286200016 ER PT J AU Osipov, VV Petukhov, AG Smelyanskiy, VN AF Osipov, VV Petukhov, AG Smelyanskiy, VN TI Complete spin polarization of electrons in semiconductor layers and quantum dots SO APPLIED PHYSICS LETTERS LA English DT Article ID INJECTION; TRANSPORT; TRANSISTOR; JUNCTIONS AB We demonstrate that nonequilibrium electrons in thin nonmagnetic semiconductor layers or quantum dots can be fully spin polarized by means of simultaneous electrical spin injection and extraction. The complete spin polarization is achieved if the thin layers or quantum dots are placed between two ferromagnetic metal contacts with moderate spin injection coefficients and antiparallel magnetizations. The sign of the spin polarization is determined by the direction of the current. Applications of this effect in spintronics and quantum information processing are discussed. (C) 2005 American Institute of Physics. C1 New Phys Devices LLC, El Segundo, CA 90245 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. S Dakota Sch Mines & Technol, Dept Phys, Rapid City, SD 57701 USA. RP New Phys Devices LLC, 2041 Rosecrans Ave, El Segundo, CA 90245 USA. EM osipov@email.arc.nasa.gov NR 23 TC 3 Z9 3 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0003-6951 EI 1077-3118 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD NOV 14 PY 2005 VL 87 IS 20 AR 202112 DI 10.1063/1.2128060 PG 3 WC Physics, Applied SC Physics GA 983PC UT WOS:000233243600046 ER PT J AU Qiu, YM Yang, RQ AF Qiu, YM Yang, RQ TI Room temperature continuous-wave operation of InAsSb quantum-dot distributed feedback lasers SO APPLIED PHYSICS LETTERS LA English DT Article ID 001 INP SUBSTRATE; 1.3 MU-M; DASH LASERS; WAVELENGTH; 1.3-MU-M AB InAsSb self-assembled quantum-dot (QD) distributed feedback (DFB) lasers based on (001) InP substrate have been grown by metalorganic vapor-phase epitaxy. A highly tensile-strained InGaAs was used as the barrier layer for InAsSb QDs. Single-mode emissions near 1.87 mu m have been demonstrated from narrow ridge waveguide DFB lasers in continuous-wave operation at temperatures up to 320 K (47 degrees C), with a characteristics temperature of 55 K up to temperature of 310 K. (C) 2005 American Institute of Physics. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Qiu, YM (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM yueming.qiu@jpl.nasa.gov NR 16 TC 1 Z9 1 U1 0 U2 2 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 NOV 14 PY 2005 VL 87 IS 20 AR 203102 DI 10.1063/1.2130527 PG 3 WC Physics, Applied SC Physics GA 983PC UT WOS:000233243600059 ER PT J AU Park, C Smith, JG Connell, JW Lowther, SE Working, DC Siochi, EJ AF Park, C Smith, JG Connell, JW Lowther, SE Working, DC Siochi, EJ TI Polyimide/silica hybrid-clay nanocomposites SO POLYMER LA English DT Article DE clay; organic-inorganic hybrid; nanocomposite ID MECHANICAL-PROPERTIES; NANOLAYER REINFORCEMENT; NATURAL-RUBBER; POLYMERIZATION; INTERCALATION; METHACRYLATE) AB A hybrid-clay nanocomposite was prepared by dispersing organically modified layered silicates (organoclay) into an organic-inorganic hybrid matrix. Layered silicates were dispersed in a hybrid matrix consisting of an alkoxysilane terminated amide acid oligomer and tetraethoxysilane. Transmission electron microscopy (TEM) and wide angle X-ray diffraction (WXRD) confirmed uniform dispersion and a high degree of predominantly exfoliated layered silicates. Storage modulus of the hybrid film containing 5 wt% exfoliated clay was 300% higher above the glass transition temperature and 30% higher at room temperature. The room temperature tensile strength and elongation to break decreased moderately with increasing clay loading. This approach provided a means of achieving excellent dispersion of predominantly exfoliated clay by reacting hydroxyl groups in the inorganic and organic precursors with hydroxyl groups at the edges of the clay layers. (c) 2005 Elsevier Ltd. All rights reserved. C1 NASA Langley Res Ctr, Natl Inst Aerosp, Hampton, VA 23681 USA. NASA Langley Res Ctr, Adv Mat & Proc Branch, Hampton, VA 23681 USA. RP Park, C (reprint author), NASA Langley Res Ctr, Natl Inst Aerosp, MS-226, Hampton, VA 23681 USA. EM c.park@larc.nasa.gov NR 31 TC 46 Z9 48 U1 2 U2 11 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0032-3861 J9 POLYMER JI Polymer PD NOV 14 PY 2005 VL 46 IS 23 BP 9694 EP 9701 DI 10.1016/j.polymer.2005.08.017 PG 8 WC Polymer Science SC Polymer Science GA 978SQ UT WOS:000232893700021 ER PT J AU Schmidt, GA Hoffmann, G Shindell, DT Hu, YY AF Schmidt, GA Hoffmann, G Shindell, DT Hu, YY TI Modeling atmospheric stable water isotopes and the potential for constraining cloud processes and stratosphere-troposphere water exchange SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID GENERAL-CIRCULATION MODEL; TROPICAL TROPOPAUSE TEMPERATURES; HEAT-FLUX; VAPOR; TRANSPORT; CLIMATE; TRACERS; SIMULATION; ICE; DEUTERIUM AB Stable water isotope tracers (HDO and (H2O)-O-18) are incorporated into the ModelE version of the Goddard Institute for Space Studies Atmospheric (GISS) General Circulation Model (GCM). Details of the moist convective parameterisation, cloud phase, background ozone, isotope kinetics and vertical resolution are varied and we examine their impacts, particularly in the upper troposphere (UT) and lower stratosphere. We find that isotopes in precipitation, except in Antarctica, are largely unaffected by these changes and thus are not a useful metric for evaluating model skill above the lower troposphere. Simulated isotopic entry values into the stratosphere over all experiments range between -750 and -600% for HDO, and -130 to -90% for (H2O)-O-18, demonstrating that the mixing processes simulated by the model can explain a significant part of the observed offset from pure Rayleigh distillation. Isotope fields are shown to be sensitive to the parameterisation of cloud physics and representation of UT processes and therefore may be useful in constraining modeled cloud physics and mechanisms of stratosphere-troposphere water vapour exchange. C1 NASA, Goddard Inst Space Studies, New York, NY 10025 USA. Columbia Univ, Ctr Climate Syst Res, New York, NY 10025 USA. Climat & Environm, Lab Sci, Orme Des Merisiers, France. Peking Univ, Dept Atmospher Sci, Beijing 100871, Peoples R China. RP Schmidt, GA (reprint author), NASA, Goddard Inst Space Studies, 2880 Broadway, New York, NY 10025 USA. EM gschmidt@giss.nasa.gov; hoffmann@lsce.saclay.cea.fr; dshindell@giss.nasa.gov; yongyunhu@pku.edu.cn RI Shindell, Drew/D-4636-2012; Schmidt, Gavin/D-4427-2012; Hu, Yongyun /B-6786-2016 OI Schmidt, Gavin/0000-0002-2258-0486; Hu, Yongyun /0000-0002-4003-4630 NR 58 TC 106 Z9 113 U1 3 U2 21 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 NOV 12 PY 2005 VL 110 IS D21 AR D21314 DI 10.1029/2005JD005790 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 985DG UT WOS:000233355700004 ER PT J AU Brown, MV Fuhrman, JA AF Brown, MV Fuhrman, JA TI Marine bacterial microdiversity as revealed by internal transcribed spacer analysis SO AQUATIC MICROBIAL ECOLOGY LA English DT Article DE microbial ecology; microdiversity; intergenic transcribed spacer ID MICROBIAL DIVERSITY; RIBOSOMAL DNA; SAR11 CLUSTER; SEQUENCES; GENOME; PROCHLOROCOCCUS; SYNECHOCOCCUS; BIODIVERSITY; COMMUNITIES; PROKARYOTES AB A growing body of evidence suggests analysis of 16S rRNA gene sequences provides only a conservative estimate of the actual genetic diversity existing within microbial communities. We examined the less conserved internal transcribed spacer (ITS) region of the ribosomal operon to determine the impact microdiversity may have on our view of marine microbial consortia. Analysis of over 500 ITS sequences and 250 associated 16S rRNA gene sequences from an oceanic time series station in the San Pedro Channel, California, USA, revealed that the community in this region is composed of large numbers of distinct lineages, with more than 1000 lineages estimated from 3 clusters alone (the SAR11 clade, the Prochlorococcus low-B/A clade 1, and the Roseobacter NAC11-7 clade). Although we found no instances where divergent ITS sequences were associated with identical 16S rRNA gene sequences, the ITS region showed much greater pairwise divergence between clones. By comparison to our 16S rRNA gene-ITS region linked database, we were able to place an ITS sequences into a phylogenetic framework, allowing them to act as an alternative molecular marker with enhanced resolution. Comparison of SAR11 clade ITS sequences with those available in GenBank indicated phylogenetic groupings based not only on depth but also on geography, potentially indicating localized differentiation or adaptation. C1 Univ So Calif, Wrigley Inst Environm Studies, Los Angeles, CA 90089 USA. Univ So Calif, Dept Biol Sci, Los Angeles, CA 90089 USA. RP Brown, MV (reprint author), Univ Hawaii, NASA, Astrobiol Inst, Honolulu, HI 96822 USA. EM mbrown@ifa.hawaii.edu RI Fuhrman, Jed/C-6461-2013 NR 31 TC 73 Z9 75 U1 2 U2 6 PU INTER-RESEARCH PI OLDENDORF LUHE PA NORDBUNTE 23, D-21385 OLDENDORF LUHE, GERMANY SN 0948-3055 J9 AQUAT MICROB ECOL JI Aquat. Microb. Ecol. PD NOV 11 PY 2005 VL 41 IS 1 BP 15 EP 23 DI 10.3354/ame041015 PG 9 WC Ecology; Marine & Freshwater Biology; Microbiology SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Microbiology GA 989TE UT WOS:000233696000002 ER PT J AU Rossow, WB Tselioudis, G Polak, A Jakob, C AF Rossow, WB Tselioudis, G Polak, A Jakob, C TI Tropical climate described as a distribution of weather states indicated by distinct mesoscale cloud property mixtures SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID WESTERN PACIFIC; FLOW REGIMES; LIFE-CYCLE; WEB SITE; ISCCP; CONVECTION; IDENTIFICATION; MIDLATITUDE; DYNAMICS; SYSTEMS AB An analysis approach that uses the patterns of cloud property joint distributions at mesoscale ( cloud type mixtures) from the International Satellite Cloud Climatology Project to identify distinct weather states of the tropical atmosphere is extended to the whole tropics covering the period 1983 - 2004. These patterns can be used as the basis for multi-scale, multi-variate compositing of other observations to understand how tropical cloud systems affect the atmospheric diabatic heating and interact with the large scale circulation. We illustrate how variations of the tropical climate on longer time scales can be described in terms of the changes in the frequency of occurrence of these weather states with their associated multivariate relationships. C1 NASA, Goddard Inst Space Studies, New York, NY 10025 USA. Columbia Univ, Dept Appl Phys & Appl Math, New York, NY 10025 USA. SGT Inc, New York, NY 10025 USA. Bur Meteorol Res Ctr, Melbourne, Vic 3001, Australia. RP Rossow, WB (reprint author), NASA, Goddard Inst Space Studies, New York, NY 10025 USA. EM wrossow@giss.nasa.gov RI Rossow, William/F-3138-2015; Jakob, Christian/A-1082-2010 OI Jakob, Christian/0000-0002-5012-3207 NR 28 TC 82 Z9 82 U1 2 U2 12 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 NOV 11 PY 2005 VL 32 IS 21 AR L21812 DI 10.1029/2005GL024584 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 985CS UT WOS:000233354300009 ER PT J AU Chen, JH Fritz, TA Sheldon, RB AF Chen, JH Fritz, TA Sheldon, RB TI Multiple spacecraft observations of energetic ions during a high solar wind pressure event SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID EARTHS BOW SHOCK; INTERPLANETARY MAGNETIC-FIELD; MAGNETOSHEATH IONS; PARTICLE EVENTS; OUTER CUSP; POLAR-CAP; UPSTREAM; MAGNETOSPHERE; ACCELERATION; ELECTRONS AB [1] On 28 June 1999 the Wind spacecraft ( near the forward libration point) observed a large solar wind pressure spike from 0445 UT to 0600 UT. The Polar satellite at 7 hours magnetic local time detected an energetic particle event in the high-altitude region associated with turbulent diamagnetic cavities from 0512 UT to 0627 UT. The particles and cavities are very similar to those that were previously found in the high-altitude dayside cusp region. They are independent of both the solar wind velocity and the interplanetary magnetic field ( IMF) vectors. The enhancements of the magnetic field fluctuations in the ultra-low frequency range measured by the Wind were also observed by the Polar. Most of the time, during the event period, the IMF had a duskward component, suggesting that cusp diamagnetic cavities also existed in the postnoon sector in the Northern Hemisphere. Energetic ions of both ionospheric origin and solar wind origin were observed by the Polar spacecraft during this event period. The He++/H+ ratio in the diamagnetic cavities was a factor of four higher than in the quasi-trapping region before the event onset, while the He+/ He++ ratio in the cavities was more than one order of the magnitude lower. In this event, the measured cusp ions had energies up to 4 MeV. No clear relationship between the cusp energetic ion flux and the IMF cone angle was found. The Interball 1 spacecraft located just upstream of the bow shock in the prenoon sector measured an upstream ion event from about 0516 UT to 0600 UT. The onset of the energetic ions observed by Interball 1 in the upstream event was the same for different energies; the ion energy spectra were independent of the solar wind velocity and their intensities were independent of the bow shock geometry and the solar wind density. The energetic ion event onset was first detected in the cusp by Polar at 0512 UT, then near the bow shock in the prenoon by Interball 1 at 0516 UT, and then in the far upstream by Wind at 0523 UT. The measured energetic ion intensity decreased with increasing distance from the cusp diamagnetic cavities. These observational facts together with the IMF directions suggest that ( 1) this large solar wind pressure event produced an extremely large diamagnetic cavity (> 10 R-E) within the magnetosphere, ( 2) the bow shock was not the main source of both the cusp and upstream energetic ions, and ( 3) the upstream energetic ions most likely came from the cusp. C1 Boston Univ, Ctr Space Phys, Boston, MA 02215 USA. NASA, Natl Space Sci & Technol Ctr, George C Marshall Space Flight Ctr, Huntsville, AL 35805 USA. RP Chen, JH (reprint author), Boston Univ, Ctr Space Phys, 725 Commonwealth Ave, Boston, MA 02215 USA. EM jschen@bu.edu; fritz@bu.edu; rob.sheldon@msfc.nasa.gov NR 52 TC 5 Z9 5 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 NOV 11 PY 2005 VL 110 IS A11 AR A11212 DI 10.1029/2005JA011043 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 985DT UT WOS:000233357100005 ER PT J AU Jasinski, MF Borak, J Crago, R AF Jasinski, MF Borak, J Crago, R TI Bulk surface momentum parameters for satellite-derived vegetation fields SO AGRICULTURAL AND FOREST METEOROLOGY LA English DT Article DE roughness length; vegetation; momentum; remote sensing ID ZERO-PLANE DISPLACEMENT; AERODYNAMIC ROUGHNESS; TALL VEGETATION; LANDES FOREST; AREA INDEX; LEAF-AREA; MODEL; LENGTH; IMAGERY; CANOPY AB The bulk aerodynamic parameters associated with the absorption of surface momentum by vegetated landscapes are theoretically estimated within the context of Raupach's roughness sublayer formulation. The parameters include the bulk plant drag coefficient, maximum u*/U-h, sheltering coefficient, and canopy area density at onset of sheltering. Parameters are estimated for the four principal IGBP land cover classes within the U.S. Southern Great Plains: evergreen needleleaf forests, grasslands, croplands, and open shrublands. The estimation approach applies the Method of Moments to roughness data from several international field experiments and other published sources. The results provide the necessary land surface parameters for satellite-based estimation of momentum aerodynamic roughness length and zero-plane displacement height for seasonally variable vegetation fields employed in most terrestrial and atmospheric simulation models used today. Construction of sample displacement and roughness maps over the Southern United States using MODIS land products demonstrates the potential of this approach for regional to global applications. (c) 2005 Elsevier B.V. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Hydrol Sci Branch, Greenbelt, MD 20771 USA. Sci Syst & Applicat Inc, Greenbelt, MD 20771 USA. Bucknell Univ, Dept Civil & Environm Engn, Lewisburg, PA 17837 USA. RP Jasinski, MF (reprint author), NASA, Goddard Space Flight Ctr, Hydrol Sci Branch, Code 614-3, Greenbelt, MD 20771 USA. EM Michael.F.Jasinski@nasa.gov; borak@hsb.gsfc.nasa.gov; rcrago@bucknell.edu NR 41 TC 14 Z9 18 U1 0 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-1923 J9 AGR FOREST METEOROL JI Agric. For. Meteorol. PD NOV 10 PY 2005 VL 133 IS 1-4 BP 55 EP 68 DI 10.1016/j.agrfonnet.2005.07.017 PG 14 WC Agronomy; Forestry; Meteorology & Atmospheric Sciences SC Agriculture; Forestry; Meteorology & Atmospheric Sciences GA 998IS UT WOS:000234312600007 ER PT J AU Liu, X Zhang, SN AF Liu, X Zhang, SN TI Non-Gaussianity due to possible residual foreground signals in Wilkinson Microwave Anistropy Probe first-year data using spherical wavelet approaches SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmic microwave background; methods : data analysis ID DETECT NON-GAUSSIANITY; BACKGROUND-RADIATION; WMAP OBSERVATIONS; INFLATIONARY UNIVERSE; CROSS-CORRELATION; MAPS; FLUCTUATIONS; STATISTICS; EMISSION; SKY AB We perform multiscale non-Gaussianity detection and localization to the Wilkinson Microwave Anisotropy Probe (WMAP) first-year data in both wavelet and real spaces. Such an analysis is facilitated by spherical wavelet transform and inverse transform techniques developed by the YAWtb team. Skewness and kurtosis as test statistics are calculated on scales from about 1 degrees to 30 degrees on the sky, as well as toward different directions using anisotropic spherical Morlet wavelets (SMW). A maximum deviation from Gaussian simulations with a right tail probability of similar to 99.9% is detected at an angular scale of similar to 12 degrees at an azimuthal orientation of similar to 0 degrees on the sky. In addition, some significant non-Gaussian spots have been identified and localized in real space from both the combined Q-V-W map recommended by the WMAP team and the Tegmark foreground-cleaned map. Systematic effects due to beams and noise can be rejected as the source of this non-Gaussianity. Several tests show that residual foreground contamination may significantly contribute to this non-Gaussian feature. It is thus still premature to do more precise tests on the non-Gaussianity of the intrinsic CMB fluctuations before we can identify the origin of these foreground signals, understand their nature, and finally remove them from the CMB maps completely. C1 Tsing Hua Univ, Dept Phys, Beijing 100084, Peoples R China. Tsing Hua Univ, Tsinghua Ctr Astrophys, Beijing 100084, Peoples R China. Univ Alabama, Dept Phys, Huntsville, AL 35899 USA. NASA, George C Marshall Space Flight Ctr, Space Sci Lab, Huntsville, AL 35812 USA. Chinese Acad Sci, Inst High Energy Phys, Key Lab Particle Astrophys, Beijing 100039, Peoples R China. RP Liu, X (reprint author), Tsing Hua Univ, Dept Phys, Beijing 100084, Peoples R China. EM liuxin00@tsinghua.org.cn; zhangsn@tsinghua.edu.cn NR 48 TC 19 Z9 19 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 NOV 10 PY 2005 VL 633 IS 2 BP 542 EP 551 DI 10.1086/431729 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 983NK UT WOS:000233239000002 ER PT J AU Kraemer, SB George, IM Crenshaw, DM Gabel, JR Turner, TJ Gull, TR Hutchings, JB Kriss, GA Mushotzky, RF Netzer, H Peterson, BM Behar, E AF Kraemer, SB George, IM Crenshaw, DM Gabel, JR Turner, TJ Gull, TR Hutchings, JB Kriss, GA Mushotzky, RF Netzer, H Peterson, BM Behar, E TI Simultaneous ultraviolet and X-ray observations of Seyfert galaxy NGC 4151. I. Physical conditions in the X-ray absorbers SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : individual (NGC 4151); galaxies : Seyfert; X-rays : galaxies ID ACTIVE GALACTIC NUCLEI; TELESCOPE IMAGING SPECTROGRAPH; TRANSMISSION GRATING SPECTROMETER; SHORT-TIMESCALE VARIABILITY; INTRINSIC ABSORPTION-LINES; SPACE-TELESCOPE; NGC 4151; WARM ABSORBERS; HEATED WINDS; IONIZED-GAS AB We present a detailed analysis of the intrinsic X-ray absorption in the Seyfert 1 galaxy NGC 4151 using Chandra High Energy Transmission Grating Spectrometer data obtained in 2002 May as part of a program that included simultaneous ultraviolet (UV) spectra using the Hubble Space Telescope Space Telescope Imaging Spectrograph and the Far Ultraviolet Spectrographic Explorer. Previous studies, most recently using Advanced Satellite for Cosmology and Astrophysics (ASCA) spectra, revealed a large (> 10(22) cm(-2)) column of intervening gas, which has varied both in ionization state and total column density. NGC 4151 was in a relatively low flux state during the observations reported here (similar to 25% of its historic maximum), although roughly 2.5 times as bright in the 2-10 keV band as during a Chandra observation in 2000. At both epochs, the soft X-ray band was dominated by emission lines, which show no discernible variation in flux between the two observations. The 2002 Chandra data show the presence of a very highly ionized absorber, in the form of H-like and He-like Mg, Si, and S lines, as well as lower ionization gas via the presence of inner-shell absorption lines from lower ionization species of these elements. The latter accounts for both the bulk of the soft X-ray absorption and the high covering factor UV absorption lines of O VI, C IV, and N V with outflow velocities approximate to 500 km s(-1). The presence of high-ionization gas, which is not easily detected at low resolution (e.g., with ASCA), appears common among Seyfert galaxies. Since this gas is too highly ionized to be radiatively accelerated in sources such as NGC 4151, which is radiating at a small fraction of its Eddington Luminosity, it may be key to understanding the dynamics of mass outflow. We find that the deeper broadband absorption detected in the 2000 Chandra data is the result of both (1) lower ionization of the intervening gas due to the lower ionizing flux and (2) a factor of similar to 3 higher column density of the lower ionization component. To account for this bulk motion, we estimate that this component must have a velocity greater than or similar to 1250 km s(-1) transverse to our line of sight. This is consistent with the rotational velocity of gas arising from the putative accretion disk. While both thermal wind and magnetohydrodynamic models predict large nonradial motions, we suggest that the latter mechanism is more consistent with the results of the photoionization models of the absorbers. C1 Catholic Univ Amer, Dept Phys, Inst Astrophys & Computat Sci, Washington, DC 20064 USA. NASA, Goddard Space Flight Ctr, Explorat Universe Div, Greenbelt, MD 20771 USA. Univ Maryland Baltimore Cty, Dept Phys, Baltimore, MD 21250 USA. Georgia State Univ, Dept Phys & Astron, Atlanta, GA 30303 USA. Univ Colorado, CASA, Boulder, CO 80309 USA. Natl Res Council Canada, Dominion Astrophys Observ, Victoria, BC V8X 4M6, Canada. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Tel Aviv Univ, Raymond & Beverly Sackler Fac Exact Sci, Sch Phys & Astron, IL-69978 Tel Aviv, Israel. Ohio State Univ, Dept Astron, Columbus, OH 43210 USA. Technion Israel Inst Technol, Dept Phys, IL-32000 Haifa, Israel. RP Kraemer, SB (reprint author), Catholic Univ Amer, Dept Phys, Inst Astrophys & Computat Sci, Washington, DC 20064 USA. EM kraemer@yancey.gsfc.nasa.gov RI Gull, Theodore/D-2753-2012 OI Gull, Theodore/0000-0002-6851-5380 NR 72 TC 62 Z9 63 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 NOV 10 PY 2005 VL 633 IS 2 BP 693 EP 705 DI 10.1086/466522 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 983NK UT WOS:000233239000016 ER PT J AU Dale, DA Bendo, GJ Engelbracht, CW Gordon, KD Regan, MW Armus, L Cannon, JM Calzetti, D Draine, BT Helou, G Joseph, RD Kennicutt, RC Li, A Murphy, EJ Roussel, H Walter, F Hanson, HM Hollenbach, DJ Jarrett, TH Kewley, LJ Lamanna, CA Leitherer, C Meyer, MJ Rieke, GH Rieke, MJ Sheth, K Smith, JDT Thornley, MD AF Dale, DA Bendo, GJ Engelbracht, CW Gordon, KD Regan, MW Armus, L Cannon, JM Calzetti, D Draine, BT Helou, G Joseph, RD Kennicutt, RC Li, A Murphy, EJ Roussel, H Walter, F Hanson, HM Hollenbach, DJ Jarrett, TH Kewley, LJ Lamanna, CA Leitherer, C Meyer, MJ Rieke, GH Rieke, MJ Sheth, K Smith, JDT Thornley, MD TI Infrared spectral energy distributions of nearby galaxies SO ASTROPHYSICAL JOURNAL LA English DT Article DE infrared : galaxies; infrared : ISM ID STAR-FORMING GALAXIES; MULTIBAND IMAGING PHOTOMETER; CLERK-MAXWELL-TELESCOPE; INTERSTELLAR DUST; EMISSION; SPITZER; COLORS; MODELS; ATLAS; SINGS AB The Spitzer Infrared Nearby Galaxies Survey (SINGS) is carrying out a comprehensive multiwavelength survey on a sample of 75 nearby galaxies. The 1 - 850 mu m spectral energy distributions (SEDs) are presented using broadband imaging data from Spitzer, 2MASS, ISO, IRAS, and SCUBA. The infrared colors derived from the globally integrated Spitzer data are generally consistent with the previous generation of models that were developed using global data for normal star-forming galaxies, although significant deviations are observed. Spitzer's excellent sensitivity and resolution also allow a detailed investigation of the infrared SEDs for various locations within the three large, nearby galaxies NGC 3031 (M81), NGC 5194 (M51), and NGC 7331. A wide variety of spectral shapes is found within each galaxy, especially for NGC 3031, the closest of the three targets and thus the galaxy for which the smallest spatial scales can be explored. Strong correlations exist between the local star formation rate and the infrared colors f(nu)(70 mu m)/ f(nu)(160 mu m) and f(nu)(24 mu m)/ f(nu)(160 mu m), suggesting that the 24 and 70 mu m emission are useful tracers of the local star formation activity level. Preliminary evidence indicates that variations in the 24 mu m emission, and not variations in the emission from polycyclic aromatic hydrocarbons at 8 mu m, drive the variations in the f(nu)(8.0 mu m)/ f(nu)(24 mu m) colors within NGC 3031, NGC 5194, and NGC 7331. If the galaxy-to-galaxy variations in SEDs seen in our sample are representative of the range present at high redshift, then extrapolations of total infrared luminosities and star formation rates from the observed 24 mu m flux will be uncertain at the factor of 5 level ( total range). The corresponding uncertainties using the redshifted 8.0 mu m flux (e.g., observed 24 mu m flux for a z = 2 source) are factors of 10 - 20. Considerable caution should be used when interpreting such extrapolated infrared luminosities. C1 Univ Wyoming, Dept Phys & Astron, Laramie, WY 82071 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. CALTECH, Pasadena, CA 91101 USA. Max Planck Inst Astron, D-69117 Heidelberg, Germany. Princeton Univ Observ, Princeton, NJ 08544 USA. Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA. Univ Missouri, Dept Phys & Astron, Columbia, MO 65211 USA. Yale Univ, Dept Astron, New Haven, CT 06520 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Bucknell Univ, Dept Phys, Lewisburg, PA 17837 USA. RP Univ Wyoming, Dept Phys & Astron, Laramie, WY 82071 USA. EM ddale@uwyo.edu OI Draine, Bruce/0000-0002-0846-936X NR 36 TC 206 Z9 206 U1 0 U2 3 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 NOV 10 PY 2005 VL 633 IS 2 BP 857 EP 870 DI 10.1086/491642 PN 1 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 983NK UT WOS:000233239000028 ER PT J AU Calzetti, D Kennicutt, RC Bianchi, L Thilker, DA Dale, DA Engelbracht, CW Leitherer, C Meyer, MJ Sosey, ML Mutchler, M Regan, MW Thornley, MD Armus, L Bendo, GJ Boissier, S Boselli, A Draine, BT Gordon, KD Helou, G Hollenbach, DJ Kewley, L Madore, BF Martin, DC Murphy, EJ Rieke, GH Rieke, MJ Roussel, H Sheth, K Smith, JD Walter, F White, BA Yi, S Scoville, NZ Polletta, M Lindler, D AF Calzetti, D Kennicutt, RC Bianchi, L Thilker, DA Dale, DA Engelbracht, CW Leitherer, C Meyer, MJ Sosey, ML Mutchler, M Regan, MW Thornley, MD Armus, L Bendo, GJ Boissier, S Boselli, A Draine, BT Gordon, KD Helou, G Hollenbach, DJ Kewley, L Madore, BF Martin, DC Murphy, EJ Rieke, GH Rieke, MJ Roussel, H Sheth, K Smith, JD Walter, F White, BA Yi, S Scoville, NZ Polletta, M Lindler, D TI Star formation in NGC 5194 (M51a): The panchromatic view from GALEX to Spitzer SO ASTROPHYSICAL JOURNAL LA English DT Review DE galaxies : interactions; galaxies : ISM; galaxies : starburst; ISM : structure ID SMALL-MAGELLANIC-CLOUD; ULTRAVIOLET LUMINOSITY DENSITY; H-II REGIONS; SPECTRAL ENERGY-DISTRIBUTION; GALAXY-EVOLUTION-EXPLORER; LOCAL STARBURST GALAXIES; NEARBY MOLECULAR CLOUDS; INITIAL MASS FUNCTION; DIFFUSE IONIZED-GAS; FORMING GALAXIES AB Far-ultraviolet to far-infrared images of the nearby galaxy NGC 5194 (M51a), from a combination of space-based (Spitzer, GALEX, and Hubble Space Telescope) and ground-based data, are used to investigate local and global star formation and the impact of dust extinction. The Spitzer data provide unprecedented spatial detail in the infrared, down to sizes similar to 500 pc at the distance of NGC 5194. The multiwavelength set is used to trace the relatively young stellar populations, the ionized gas, and the dust absorption and emission in H II - emitting knots, over 3 orders of magnitude in wavelength range. As is common in spiral galaxies, dust extinction is high in the center of the galaxy ( A(V) similar to 3.5 mag), but its mean value decreases steadily as a function of galactocentric distance, as derived from both gas emission and stellar continuum properties. In the IR/UV-UV color plane, the NGC 5194 H II knots show the same trend observed for normal star-forming galaxies, having a much larger dispersion ( similar to 1 dex peak to peak) than starburst galaxies. We identify the dispersion as due to the UV emission predominantly tracing the evolved, nonionizing stellar population, up to ages similar to 50 - 100 Myr. While in starbursts the UV light traces the current star formation rate (SFR), in NGC 5194 it traces a combination of current and recent past SFRs. Possibly, mechanical feedback from supernovae is less effective at removing dust and gas from the star formation volume in normal star-forming galaxies than in starbursts because of the typically lower SFR densities in the former. The application of the starburst opacity curve for recovering the intrinsic UV emission ( and deriving SFRs) in local and distant galaxies appears therefore appropriate only for SFR densities greater than or similar to 1 M(.) yr(-1) kpc(-2). Unlike the UV emission, the monochromatic 24 mu m luminosity is an accurate local SFR tracer for the H II knots in NGC 5194, with a peak-to-peak dispersion of less than a factor of 3 relative to hydrogen emission line tracers; this suggests that the 24 mu m emission carriers are mainly heated by the young, ionizing stars. However, preliminary results show that the ratio of the 24 mu m emission to the SFR varies by a factor of a few from galaxy to galaxy; this variation needs to be understood and carefully quantified before the 24 mu m luminosity can be used as an SFR tracer for galaxy populations. While also correlated with star formation, the 8 mu m emission is not directly proportional to the number of ionizing photons; it is overluminous, by up to a factor of similar to 2, relative to the galaxy's average in weakly ionized regions and is underluminous, by up to a factor of similar to 3, in strongly ionized regions. This confirms earlier suggestions that the carriers of the 8 mu m emission are heated by more than one mechanism. C1 Space Telescope Sci Inst, Baltimore, MD 21218 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Univ Wyoming, Dept Phys, Laramie, WY 82071 USA. Bucknell Univ, Dept Phys, Lewisburg, PA 17837 USA. CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA. Carnegie Inst Washington, Carnegie Observ, Pasadena, CA 91101 USA. Lab Astrophys Marseille, F-13376 Marseille, France. Princeton Univ Observ, Princeton, NJ 08544 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA. Yale Univ, Dept Astron, New Haven, CT 06520 USA. Max Planck Inst Astron, D-69117 Heidelberg, Germany. Univ Oxford, Dept Phys, Clarendon Lab, Oxford OX1 3PU, England. Sigma Res & Engn, Lanham, MD 20706 USA. RP Calzetti, D (reprint author), Space Telescope Sci Inst, 3700 San Martin Dr, Baltimore, MD 21218 USA. EM calzetti@stsci.edu OI Polletta, Maria del Carmen/0000-0001-7411-5386; Draine, Bruce/0000-0002-0846-936X NR 101 TC 300 Z9 301 U1 0 U2 3 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 NOV 10 PY 2005 VL 633 IS 2 BP 871 EP 893 DI 10.1086/466518 PN 1 PG 23 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 983NK UT WOS:000233239000029 ER PT J AU Focke, WB Wai, LL Swank, JH AF Focke, WB Wai, LL Swank, JH TI Time domain studies of X-ray shot noise in Cygnus X-1 SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; binaries : general; black hole physics; methods : data analysis; stars : individual (Cygnus X-1); X-rays : stars ID BLACK-HOLE; LOW STATE; VARIABILITY; FLUCTUATIONS; MODELS; FLARES AB We investigate the variability of Cyg X-1 in the context of shot-noise models and employ a peak detection algorithm to select individual shots. For a long observation of the low, hard state, the distribution of time intervals between shots is found to be consistent with a purely random process, contrary to previous claims in the literature. The detected shots are fit to several model templates and found to have a broad range of shapes. The fitted shots have a distribution of timescales from below 10 ms to above 1 s. The coherence of the cross spectrum of light curves of these data in different energy bands is also studied. The observed high coherence implies that the transfer function between low- and high-energy variability is uniform. The uniformity of the transfer function implies that the observed distribution of shot widths cannot have been acquired through Compton scattering. Our results in combination with other results in the literature suggest that shot luminosities are correlated with one another. We discuss how our experimental methodology relates to nonlinear models of variability. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. NASA, Goddard Space Flight Ctr, Xray Astrophys Lab, Greenbelt, MD 20771 USA. RP Focke, WB (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, MS 98,2575 Sand Hill Rd, Menlo Pk, CA 94025 USA. EM focke@slac.stanford.edu; wai@slac.stanford.edu; jean.h.swank@nasa.gov RI Swank, Jean/F-2693-2012 NR 22 TC 7 Z9 7 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 NOV 10 PY 2005 VL 633 IS 2 BP 1085 EP 1094 DI 10.1086/462407 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 983NK UT WOS:000233239000049 ER PT J AU Debes, JH Sigurdsson, S Woodgate, BE AF Debes, JH Sigurdsson, S Woodgate, BE TI Cool customers in the stellar graveyard. I. Limits to extrasolar planets around the white dwarf G29-38 SO ASTROPHYSICAL JOURNAL LA English DT Article DE circumstellar matter; planetary systems; stars : individual (G29-38); white dwarfs ID PALOMAR-GREEN SURVEY; LOW-MASS STARS; BROWN DWARF; PHOTOMETRIC SYSTEMS; LUMINOSITY FUNCTION; GIANT PLANETS; COMPANION; DETECTABILITY; EVOLUTION; SPECTRA AB We present high-contrast images of the hydrogen white dwarf G29-38 taken in the near-infrared with the Hubble Space Telescope and the Gemini North Telescope as part of a high-contrast imaging search for substellar objects in orbit around nearby white dwarfs. We review the current limits on planetary companions for G29-38, the only nearby white dwarf with an infrared excess due to a dust disk. We add our recent observations to these limits to produce extremely tight constraints on the types of possible companions that could be present. No objects > 6 M-J are detected in our data at projected separations > 12 AU, and no objects > 16M(J) are detected for separations from 3 to 12 AU, assuming a total system age of 1 Gyr. Limits for companions at separations < 3 AU come from a combination of Two Micron All Sky Survey (2MASS) photometry and previous studies of G29-38' s pulsations. Our imaging with Gemini cannot confirm a tentative claim for the presence of a low-mass brown dwarf. These observations demonstrate that a careful combination of several techniques can probe nearby white dwarfs for large planets and low-mass brown dwarfs. C1 Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD USA. RP Debes, JH (reprint author), Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. RI Woodgate, Bruce/D-2970-2012; OI Sigurdsson, Steinn/0000-0002-8187-1144 NR 48 TC 15 Z9 15 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 NOV 10 PY 2005 VL 633 IS 2 BP 1168 EP 1174 DI 10.1086/491640 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 983NK UT WOS:000233239000056 ER PT J AU Sui, L Holman, GD White, SM Zhang, J AF Sui, L Holman, GD White, SM Zhang, J TI Multiwavelength analysis of a solar flare on 2002 April 15 SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : flares; Sun : X-rays, gamma rays ID EJECTION CURRENT SHEET; MAGNETIC RECONNECTION; ACTIVE-REGION; ENERGY; EMISSION; ELECTRONS; IMAGES; RHESSI; ACCELERATION; EVOLUTION AB We carried out a multiwavelength analysis of the solar limb flare on 2002 April 15. The observations all indicate that the flare occurred in an active region with an asymmetric dipole magnetic configuration. The earlier conclusion that magnetic reconnection is occurring in a large-scale current sheet in this flare is further supported by these observations: ( 1) Several bloblike sources, seen in RHESSI 12 - 25 keV X-ray images later in the flare, appeared along a line above the flare loops. These indicate the continued presence of the current sheet and are likely to be magnetic islands in the stretched sheet produced by the tearing-mode instability. ( 2) A cusplike structure is seen in Nobeyama Radioheliograph (NoRH) 34 GHz microwave images around the time of the peak flare emission. We quantitatively demonstrate that the X-ray - emitting thermal plasma seen with RHESSI had a higher temperature than the microwave-emitting plasma seen with NoRH. Since the radio data preferentially see cooler thermal plasma, this result is consistent with the picture in which energy release occurs at progressively greater heights and the hard X-rays see hot new loops while the radio sees older cooling loops. The kinetic energy of the coronal mass ejection (CME) associated with this flare was found to be about 1 order of magnitude less than both the thermal energy in the hot plasma and the non-thermal energy carried by the accelerated electrons in the flare, as deduced from the RHESSI observations. This contrasts with the higher CME kinetic energies typically deduced for large flares. C1 Catholic Univ Amer, Dept Phys, Washington, DC 20064 USA. NASA, Lab Solar & Space Phys, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Maryland, Dept Astron, College Pk, MD 20742 USA. George Mason Univ, Sch Computat Sci, Fairfax, VA 22030 USA. RP Sui, L (reprint author), Catholic Univ Amer, Dept Phys, Washington, DC 20064 USA. RI Holman, Gordon/C-9548-2012 NR 50 TC 26 Z9 26 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 NOV 10 PY 2005 VL 633 IS 2 BP 1175 EP 1186 DI 10.1086/462410 PN 1 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 983NK UT WOS:000233239000057 ER PT J AU Xu, CK Lu, N Condon, JJ Dopita, M Tuffs, RJ AF Xu, CK Lu, N Condon, JJ Dopita, M Tuffs, RJ TI Physical conditions and star formation activity in the intragroup medium of Stephan's quintet (vol 595, pg 665, 2003) SO ASTROPHYSICAL JOURNAL LA English DT Correction C1 CALTECH, Jet Prop Lab, Ctr Infrared Proc & Anal, Pasadena, CA 91125 USA. Natl Radio Astron Observ, Socorro, NM 87801 USA. Australian Natl Univ, Res Sch Astron & Astrophys, Canberra, ACT, Australia. Max Planck Inst Kernphys, D-69117 Heidelberg, Germany. RP Xu, CK (reprint author), CALTECH, Jet Prop Lab, Ctr Infrared Proc & Anal, Pasadena, CA 91125 USA. RI Dopita, Michael/P-5413-2014 OI Dopita, Michael/0000-0003-0922-4986 NR 1 TC 0 Z9 0 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 NOV 10 PY 2005 VL 633 IS 2 BP 1201 EP 1201 DI 10.1086/491578 PN 1 PG 1 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 983NK UT WOS:000233239000060 ER PT J AU Markwardt, CB Tueller, J Skinner, GK Gehrels, N Barthelmy, SD Mushotzky, RF AF Markwardt, CB Tueller, J Skinner, GK Gehrels, N Barthelmy, SD Mushotzky, RF TI The Swift/BAT high-latitude survey: First results SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; gamma rays : observations; surveys ID X-RAY SOURCES; ACTIVE GALACTIC NUCLEI; GALAXIES; AGN; SPECTRA; CATALOG; SAMPLE; SKY; UNIFICATION; EVOLUTION AB We present preliminary results from the first 3 months of the Swift Burst Alert Telescope (BAT) high Galactic latitude survey in the 14-195 keV band. The survey reaches a flux of similar to 10(-11) ergs cm(-2) s(-1) and has similar to 2.'7 (90% confidence) positional uncertainties for the faintest sources. This represents the most sensitive survey to date in this energy band. These data confirm the conjectures that a high-energy-selected active galactic nucleus (AGN) sample would have very different properties from those selected in other bands and that it represents a "true" sample of the AGN population. We have identified 86% of the 66 high-latitude sources. Twelve are Galactic-type sources, and 44 can be identified with previously known AGNs. All but five of the AGNs have archival X-ray spectra, enabling us to estimate the line-of-sight column densities and other spectral properties. Both of the z > 0.11 objects are blazars. The median redshift of the others (excluding radio-loud objects) is 0.012. We find that the column density distribution of these AGNs is bimodal, with 64% of the nonblazar sources having column densities N-H >= 10(22) cm(-2). None of the sources with log L-x > 43.5 (cgs units) show high column densities, and very few of the lower L-x sources have low column densities. Based on these data, we expect the final BAT catalog to have >200 AGNs and reach fluxes of less than similar to 10(-11) ergs cm(-2) s(-1) over the entire sky. C1 Univ Maryland, Dept Astron, College Pk, MD 20742 USA. NASA, Astroparticle Phys Lab, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. UPS, CNRS, Ctr Etud Spatiale Rayonnements, F-31028 Toulouse, France. NASA, Xray Astrophys Lab, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Markwardt, CB (reprint author), Univ Maryland, Dept Astron, College Pk, MD 20742 USA. EM craigm@milkyway.gsfc.nasa.gov RI Gehrels, Neil/D-2971-2012; Tueller, Jack/D-5334-2012; Barthelmy, Scott/D-2943-2012 NR 30 TC 102 Z9 104 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 NOV 10 PY 2005 VL 633 IS 2 BP L77 EP L80 DI 10.1086/498569 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 983NL UT WOS:000233239200004 ER PT J AU Reeves, JN Pounds, K Uttley, P Kraemer, S Mushotzky, R Yaqoob, T George, IM Turner, TJ AF Reeves, JN Pounds, K Uttley, P Kraemer, S Mushotzky, R Yaqoob, T George, IM Turner, TJ TI Evidence for gravitational infall of matter onto the supermassive black hole in the quasar PG 1211+143? SO ASTROPHYSICAL JOURNAL LA English DT Article DE black hole physics; quasars : individual (PG 1211+143); X-rays : galaxies ID ACTIVE GALACTIC NUCLEI; ALPHA PROFILE; LINE-PROFILES; DISK WINDS; IRON LINE; EMISSION; ACCRETION; ABSORPTION; PHOTOIONIZATION; GALAXIES AB We report the detection of redshifted iron K alpha absorption lines in the Chandra LETG spectrum of the narrow-line quasar PG 1211+143. The absorption lines are observed at 4.22 and 4.93 keV in the quasar spectrum, corresponding to 4.56 and 5.33 keV in the rest frame of PG 1211+143. From Monte Carlo simulations, the chance probability of both lines being false detections is low at 1.36 x 10(-4). Highly redshifted ionized iron K alpha (Fe XXV or Fe XXVI) is the most plausible identification for the lines at their observed energies. If identified with H-like iron K alpha at 6.97 keV, then the relativistic velocity shifts required are 0.40c and 0.26c. The extreme velocities can be explained by pure gravitational redshift if the matter exists in a stable orbit within 6 gravitational radii of the black hole. This would require a Kerr metric for the black hole. Alternatively, the absorption may be the result of matter infalling directly onto the black hole, with a maximum observed velocity of 0.38c at 6R(g) in the Schwarzschild metric. This matter may originate in a failed outflow or jet, which does not escape the gravitational potential of the black hole. C1 NASA, Explorat Universe Div, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. Catholic Univ Amer, Dept Phys, Washington, DC 20064 USA. Univ Maryland Baltimore Cty, Joint Ctr Astrophys, Baltimore, MD 21250 USA. RP Reeves, JN (reprint author), NASA, Explorat Universe Div, Goddard Space Flight Ctr, Greenbelt Rd, Greenbelt, MD 20771 USA. EM jnr@milkyway.gsfc.nasa.gov; kap@star.le.ac.uk; pu@milkyway.gsfc.nasa.gov; stiskraemer@yancey.gsfc.nasa.gov; richard@milkyway.gsfc.nasa.gov; yaqoob@skysrv.pha.jhu.edu; george@milkyway.gsfc.nasa.gov; turner@milkyway.gsfc.nasa.gov NR 27 TC 20 Z9 20 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 NOV 10 PY 2005 VL 633 IS 2 BP L81 EP L84 DI 10.1086/498568 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 983NL UT WOS:000233239200005 ER PT J AU Abshire, JB Sun, XL Riris, H Sirota, JM McGarry, JF Palm, S Yi, DH Liiva, P AF Abshire, JB Sun, XL Riris, H Sirota, JM McGarry, JF Palm, S Yi, DH Liiva, P TI Geoscience Laser Altimeter System (GLAS) on the ICESat mission: On-orbit measurement performance SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article AB The GLAS instrument on NASA's ICESat satellite has made over 904 million measurements of the Earth surface and atmosphere through June 2005. During its first seven operational campaigns it has vertically sampled the Earth's global surface and atmosphere on more than 3600 orbits with vertical resolutions approaching 3 cm. This paper summarizes the on-orbit measurement performance of GLAS to date. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Abshire, JB (reprint author), NASA, Goddard Space Flight Ctr, Code 690, Greenbelt, MD 20771 USA. EM james.abshire@gsfc.nasa.gov RI Abshire, James/I-2800-2013; McGarry, Jan/C-4109-2013; Riris, Haris/D-1004-2013; Sun, Xiaoli/B-5120-2013 NR 13 TC 151 Z9 160 U1 2 U2 23 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 NOV 10 PY 2005 VL 32 IS 21 AR L21S02 DI 10.1029/2005GL024028 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 985CQ UT WOS:000233354100003 ER PT J AU Fang, JY Piao, SL Zhou, LM He, JS Wei, FY Myneni, RB Tucker, CJ Tan, K AF Fang, JY Piao, SL Zhou, LM He, JS Wei, FY Myneni, RB Tucker, CJ Tan, K TI Precipitation patterns alter growth of temperate vegetation SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID CENTRAL GRASSLAND REGION; INTERANNUAL VARIATIONS; CLIMATE-CHANGE; UNITED-STATES; PRODUCTIVITY; RESPONSES; IMPACTS; INDEX; NDVI AB In this paper, we use growing season Normalized Difference Vegetation Index (NDVI) as an indicator of plant growth to quantify the relationships between vegetation production and intra-annual precipitation patterns for three major temperate biomes in China: grassland, deciduous broadleaf forest, and deciduous coniferous forest. With increased precipitation, NDVI of grassland and deciduous broadleaf forest increased, but that of deciduous coniferous forest decreased. More frequent precipitation significantly increased growth of grassland and deciduous broadleaf forest, but did not alter that of deciduous coniferous forest at low precipitation levels and constrained its growth at high precipitation levels. The relationships between NDVI and average precipitation per event were opposite to those between NDVI and precipitation frequency. Such nonlinear feedback suggests that the responses of vegetation production to changes in precipitation patterns differ by both biome type and precipitation amount. C1 Peking Univ, Coll Environm Sci, Dept Ecol, Beijing 100871, Peoples R China. Georgia Inst Technol, Sch Earth & Atmospher Sci, Atlanta, GA 30332 USA. Natl Climat Ctr, Beijing 100081, Peoples R China. Boston Univ, Dept Geog, Boston, MA 02215 USA. NASA, Biospher Sci Branch, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Fang, JY (reprint author), Peking Univ, Coll Environm Sci, Dept Ecol, Beijing 100871, Peoples R China. EM jyfang@urban.pku.edu.cn RI He, Jin-Sheng/A-4053-2009; Fang, Jingyun/A-4282-2009; Zhu, Lianhua/C-1219-2012; Zhou, Liming/A-2688-2012; Myneni, Ranga/F-5129-2012 OI He, Jin-Sheng/0000-0001-5081-3569; NR 17 TC 59 Z9 71 U1 6 U2 55 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 NOV 10 PY 2005 VL 32 IS 21 AR L21411 DI 10.1029/2005GL024231 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 985CQ UT WOS:000233354100006 ER PT J AU Trigg, SN Roy, DP Flasse, SP AF Trigg, SN Roy, DP Flasse, SP TI An in situ study of the effects of surface anisotropy on the remote sensing of burned savannah SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article ID BIDIRECTIONAL REFLECTANCE; IMAGES; NDVI AB This Letter presents field-based evidence of the perturbing effects of surface anisotropy on the remote sensing of burned savannah. The analysis is based on bidirectional spectral reflectance data collected at different solar illumination angles and convolved to Moderate-resolution Imaging Spectroradiometer ( MODIS) reflective bands. Results from a grass savannah site show that burning reduces the anisotropy of the surface compared to its pre-burn state. In contrast, at a shrub savannah site, burning reduces or increases surface anisotropy. Spectral indices defined from 1.240 mu m and 2.130 mu m reflectance, and 1.640 mu m and 2.130 mu m reflectance, provided stronger diurnal separation between burned and unburned areas than individual reflectance bands but do not eliminate anisotropic effects. The Normalized Difference Vegetation Index (NDVI) provides weak diurnal separation relative to these near- and mid-infrared based indices. Implications of the findings are discussed for burned area mapping. C1 Univ Maryland, Dept Geog, College Pk, MD 20740 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Flasse Consulting, Maidstone ME16 0AG, Kent, England. RP Trigg, SN (reprint author), Univ Maryland, Dept Geog, 2181 LeFrak Hall, College Pk, MD 20740 USA. EM trigg@umd.edu NR 17 TC 9 Z9 9 U1 0 U2 1 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD NOV 10 PY 2005 VL 26 IS 21 BP 4869 EP 4876 DI 10.1080/01431160500141923 PG 8 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA 993MD UT WOS:000233957300015 ER PT J AU Henderson, B Bridges, J Wernet, M AF Henderson, B Bridges, J Wernet, M TI An experimental study of the oscillatory flow structure of tone-producing supersonic impinging jets SO JOURNAL OF FLUID MECHANICS LA English DT Article ID AXISYMMETRICAL CHOKED JET; FLAT-PLATE; SOUND-PRODUCTION; IMPINGEMENT; FIELD AB An experimental investigation into the structure of a supersonic jet impinging on a large plate is presented. Digital particle image velocimetry (DPIV), shadowgraph photography and acoustic measurements are used to understand the relationship between the unsteady jet structure and the production of tones for nozzle-to-plate spacings between 1 and 5 nozzle exit diameters at a nozzle-pressure ratio equal to 4. Results indicate that the instability of the jet depends on the location of the plate in the shock cell structure of the corresponding free jet and the strength of the standoff shock wave, rather than on the occurrence of recirculation zones in the impingement region. Phase-locked studies show streamwise displacements of the stand-off shock wave, a moving recirculation zone in the subsonic flow in front of the plate, and significant oscillations of both the compression and expansion regions in the peripheral supersonic flow when tones are produced. Sound is shown to be generated by periodic pulsing of the wall jet boundary resulting from periodic motion of the flow in the impingement and near-wall regions of the flow. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Henderson, B (reprint author), NASA, Langley Res Ctr, Hampton, VA 23681 USA. NR 33 TC 44 Z9 47 U1 0 U2 12 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH ST, NEW YORK, NY 10011-4211 USA SN 0022-1120 J9 J FLUID MECH JI J. Fluid Mech. PD NOV 10 PY 2005 VL 542 BP 115 EP 137 DI 10.1017/S0022112005006385 PG 23 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 984HQ UT WOS:000233294100007 ER PT J AU Strekalov, D Matsko, AB Savchenkov, A Maleki, L AF Strekalov, D Matsko, AB Savchenkov, A Maleki, L TI Quantum-correlation metrology with biphotons: where is the limit? SO JOURNAL OF MODERN OPTICS LA English DT Article; Proceedings Paper CT 35th Winter Colloquium on the Physics of Quantum Electronics CY JAN 02-06, 2005 CL Snowbird, UT ID 2-PHOTON WAVE-PACKET; COHERENT; STATES AB Theoretical analysis shows that the correlation time of a photon pair is closely related to the spectrum of two-photon light. This entails limitations on the shortest achievable two-photon correlation time. These limitations are important for quantum optical metrology and information processing applications, especially those involving quasi-monochromatic light. In this paper we present a more rigorous proof of the fact that the shortest possible two-photon correlation time is limited by approximately the inverse width of the optical spectrum. We further show that this limit can be closely approached with Type-I spontaneous parametric down-conversion at a specific pump wavelength. This study also results in the prediction of very unusual parametric down-conversion spectra, suggesting a method for engineering of frequency-entangled two-photon states. C1 CALTECH, Jet Propuls Lab, Pasadena, CA 91109 USA. RP Strekalov, D (reprint author), CALTECH, Jet Propuls Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM dmitry.strekalov@jpl.nasa.gov RI Matsko, Andrey/A-1272-2007 NR 22 TC 6 Z9 7 U1 0 U2 1 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0950-0340 J9 J MOD OPTIC JI J. Mod. Opt. PD NOV 10 PY 2005 VL 52 IS 16 BP 2233 EP 2243 DI 10.1080/09500340500275827 PG 11 WC Optics SC Optics GA 982OD UT WOS:000233170600008 ER PT J AU Lu, ET Love, SG AF Lu, ET Love, SG TI Gravitational tractor for towing asteroids - A spacecraft could deflect an Earth-bound asteroid without having to dock to its surface first SO NATURE LA English DT Editorial Material C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Lu, ET (reprint author), NASA, Lyndon B Johnson Space Ctr, Mail Code CB, Houston, TX 77058 USA. EM edward.t.lu@nasa.gov NR 5 TC 78 Z9 82 U1 1 U2 21 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD NOV 10 PY 2005 VL 438 IS 7065 BP 177 EP 178 DI 10.1038/438177a PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 982BV UT WOS:000233133500035 PM 16281025 ER PT J AU Frolking, S Fahnestock, M Milliman, T McDonald, K Kimball, J AF Frolking, S Fahnestock, M Milliman, T McDonald, K Kimball, J TI Interannual variability in North American grassland biomass/productivity detected by SeaWinds scatterometer backscatter SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID ERS SCATTEROMETER; MODIS; PRODUCTIVITY; RESPONSES; DYNAMICS; LAND; NDVI AB We analyzed 2000 - 2004 growing-season SeaWinds Ku-band microwave backscatter and MODIS leaf area index (LAI) data over North America. Large anomalies in mid-growing-season mean backscatter and LAI, relative to 5-year mean values, occurred primarily in the western Great Plains; backscatter and LAI anomalies had similar spatial patterns across this region. Backscatter and LAI time series data for three similar to 10(3) km(2) regions in the western Great Plains were strongly correlated (r(2) similar to 0.6 - 0.8), and variability in mid-growing season values was well-correlated with annual precipitation ( October through September). The results indicate that SeaWinds backscatter is sensitive to interannual variability in grassland biomass/productivity, and can provide an assessment that is completely independent of optical/near-infrared remote sensing instruments. C1 Univ New Hampshire, Inst Study Earth Oceans & Space, Durham, NH 03824 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Montana, Flathead Lake Biol Stn, Div Biol Sci, Polson, MT 59860 USA. Univ Montana, Numer Terradynam Simulat Grp, Polson, MT 59860 USA. RP Frolking, S (reprint author), Univ New Hampshire, Inst Study Earth Oceans & Space, Morse Hall,39 Coll Rd, Durham, NH 03824 USA. EM steve.frolking@unh.edu RI Fahnestock, Mark/N-2678-2013; OI Milliman, Thomas/0000-0001-6234-8967 NR 18 TC 22 Z9 23 U1 0 U2 8 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 NOV 9 PY 2005 VL 32 IS 21 AR L21409 DI 10.1029/2005GL024230 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 985CP UT WOS:000233354000005 ER PT J AU Ostgaard, N Mende, SB Frey, HU Sigwarth, JB AF Ostgaard, N Mende, SB Frey, HU Sigwarth, JB TI Simultaneous imaging of the reconnection spot in the opposite hemispheres during northward IMF SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID INTERPLANETARY MAGNETIC-FIELD; CUSP AURORA; MAGNETOSPHERE; SPACECRAFT AB Cusp aurora associated with high latitude lobe reconnection was imaged simultaneously by IMAGE and Polar in the opposite hemispheres for a short time interval on September 18, 2000. These very rare images taken during strongly northward IMF and high solar wind pressure give a unique opportunity to examine the IMF and dipole tilt control of the cusp aurora and theta aurora. As suggested by theory and observations from one hemisphere, the longitudinal location of the cusp aurora is controlled by the IMF By component, whereas the > 5 degrees poleward shift of the southern cusp aurora is attributed to the effects of the dipole tilt angle. The appearance of a non-conjugate theta aurora can be explained by the more efficient reconnection process in the southern hemisphere due to IMF B-x > 0. Imaging of auroral signatures of magnetic reconnection also demonstrates the potential to examine differences in reconnection rate in the opposite hemispheres. C1 Univ Bergen, Dept Phys & Technol, N-5007 Bergen, Norway. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. NASA, Goddard Space Flight Ctr, Electrodynam Branch, Extraterr Phys Lab, Greenbelt, MD 20771 USA. RP Ostgaard, N (reprint author), Univ Bergen, Dept Phys & Technol, Allegt 55, N-5007 Bergen, Norway. EM nikolai.ostgaard@ift.uib.no NR 17 TC 15 Z9 15 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 NOV 9 PY 2005 VL 32 IS 21 AR L21104 DI 10.1029/2005GL024491 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 985CP UT WOS:000233354000007 ER PT J AU Zhao, TXP Laszlo, I Minnis, P Remer, L AF Zhao, TXP Laszlo, I Minnis, P Remer, L TI Comparison and analysis of two aerosol retrievals over the ocean in the Terra/Clouds and the Earth's Radiant Energy System - Moderate Resolution Imaging Spectroradiometer single scanner footprint data: 1. Global evaluation SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SPECTRAL RADIANCES; SIZE DISTRIBUTION; OPTICAL DEPTH; CLEAR-SKY; AVHRR; SATELLITE; ALGORITHM; MODIS; VALIDATION; CLOUDS AB [1] Satellite aerosol remote sensing entered a new era with the deployment of advanced satellite imaging instruments such as the Moderate Resolution Imaging Spectroradiometer ( MODIS) on the NASA Terra and Aqua satellites. These new instruments provide the opportunity to learn more about aerosol properties than was possible using the simpler NOAA Advanced Very High Resolution Radiometer (AVHRR), which has been used to retrieve aerosol optical thickness for more than 20 years. Combining historical AVHRR and the more advanced MODIS aerosol retrievals to form a long-term aerosol data record is critical for studying aerosol climate forcing. To achieve this objective, it is necessary to build a connection and establish consistency between the two retrievals through a careful evaluation of the two retrieval methods applied to the same data. As a first step in this effort, this paper exploits the potential of the Clouds and the Earth's Radiant Energy System (CERES) Single-Scanner Footprint (SSF) data set that includes aerosol products derived from Terra MODIS data at the same locations using both the multichannel MODIS and the two-channel AVHRR aerosol retrieval algorithms. The analysis examines the differences in the results seen over oceans on a global scale. It was found in a global mean sense that advancement in the aerosol retrieval over ocean from the MODIS algorithm relative to the AVHRR method is realized mostly in the improvement of the aerosol size parameter ( ASP) rather than in the aerosol optical thickness (AOT). However, regional differences were observed in both AOT and ASP retrieved from the MODIS and AVHRR algorithms. These are examined further in the second part of this two-part paper. Cloud contamination and surface roughness appear to affect both aerosol retrievals, effects that need further investigation. C1 Natl Environm Satellite Data & Informat Serv, Off Res & Applicat, NOAA, Camp Springs, MD 20746 USA. Univ Maryland, Earth Syst Sci Interdisciplinary Ctr, College Pk, MD 20742 USA. NASA, Div Atmospher Sci, Langley Res Ctr, Hampton, VA 23681 USA. NASA, Atmospheres Lab, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Zhao, TXP (reprint author), Natl Environm Satellite Data & Informat Serv, Off Res & Applicat, NOAA, 5200 Auth Rd, Camp Springs, MD 20746 USA. EM xuepeng.zhao@noaa.gov RI Laszlo, Istvan/F-5603-2010; Minnis, Patrick/G-1902-2010 OI Laszlo, Istvan/0000-0002-5747-9708; Minnis, Patrick/0000-0002-4733-6148 NR 42 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 NOV 9 PY 2005 VL 110 IS D21 AR D21208 DI 10.1029/2005JD005851 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 985DD UT WOS:000233355400005 ER PT J AU Zhao, TXP Laszlo, I Minnis, P Remer, L AF Zhao, TXP Laszlo, I Minnis, P Remer, L TI Comparison and analysis of two aerosol retrievals over the ocean in the Terra/Clouds and the Earth's Radiant Energy System - Moderate Resolution Imaging Spectroradiometer single scanner footprint data: 2. Regional evaluation SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID OPTICAL DEPTH; GOCART MODEL; SATELLITE; ALGORITHM; AERONET; MODIS; REFLECTANCE; CALIBRATION; CHANNELS; AVHRR AB [1] The advanced multichannel Moderate Resolution Imaging Spectroradiometer ( MODIS) and simple independent two-channel Advanced Very High Resolution Radiometer (AVHRR) aerosol retrieval algorithms were compared regionally using the Terra/ CERES-MODIS Single Scanner Footprint (SSF) data. On average, it was found that the two methods tend to overestimate 0.66-mu m aerosol optical thickness (AOT) compared to AERONET surface observations in the original SSF data. If the most cloud-free data are used, the mean satellite retrievals agree to within +/- 10% of the AERONET data. The MODIS near-infrared (1.60-mu m) AOTs are in better agreement with the surface data than the AVHRR-type retrievals. The satellite-derived aerosol size parameters are 20 - 30% smaller than the surface-based values with the MODIS values closer to the AERONET values than that of AVHRR-type. The effects of aerosol model assumptions, cloud contamination, and surface roughness on the two aerosol retrievals were analyzed in detail with the careful classification of clear-sky and surface roughness conditions. For most of the regions examined, the annual mean AOTs from the MODIS retrieval are 0.03 and 0.02 less than their AVHRR-type counterparts at 0.66 and 1.60 mu m, respectively. However, the MODIS values may exceed the AVHRR-type values in regions where the prevailing aerosol type varies with season or is under an apparent influence of cloud or surface disturbance. Examination of the surface treatments used by the two retrieval methods indicates the need for improvement over very rough ocean surfaces, especially for the AVHRR method. The results indicate that aerosol model assumptions become important for regional retrievals and the dynamic aerosol models used in the MODIS retrieval are better suited for simultaneously measuring the regional variations in aerosol optical properties and their global mean values. C1 Natl Environm Satellite Data & Informat Serv, Off Res & Applicat, NOAA, Camp Springs, MD 20746 USA. Univ Maryland, Earth Syst Sci Interdisciplinary Ctr, College Pk, MD 20742 USA. NASA, Div Atmospher Sci, Langley Res Ctr, Hampton, VA 23681 USA. NASA, Atmospheres Lab, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Zhao, TXP (reprint author), Natl Environm Satellite Data & Informat Serv, Off Res & Applicat, NOAA, 5200 Auth Rd, Camp Springs, MD 20746 USA. EM xuepeng.zhao@noaa.gov RI Laszlo, Istvan/F-5603-2010; Minnis, Patrick/G-1902-2010 OI Laszlo, Istvan/0000-0002-5747-9708; Minnis, Patrick/0000-0002-4733-6148 NR 24 TC 3 Z9 3 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 NOV 9 PY 2005 VL 110 IS D21 AR D21209 DI 10.1029/2005JD005852 PG 18 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 985DD UT WOS:000233355400006 ER PT J AU Vandemark, D Chapron, B Elfouhaily, T Campbell, JW AF Vandemark, D Chapron, B Elfouhaily, T Campbell, JW TI Impact of high-frequency waves on the ocean altimeter range bias SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID SEA-STATE BIAS; ELECTROMAGNETIC BIAS; RADAR ALTIMETRY; SURFACE; SATELLITE; SLOPE; DEPENDENCE; SPECTRUM; TOPEX; MODEL AB [1] New aircraft observations are presented on the range determination error in satellite altimetry associated with ocean waves. Laser-based measurements of the cross correlation between the gravity wave slope and elevation are reported for the first time. These observations provide direct access to a long, O(10 m), gravity wave statistic central to nonlinear wave theory prediction of the altimeter sea state bias. Coincident Ka-band radar scattering data are used to estimate an electromagnetic ( EM) range bias analogous to that in satellite altimetry. These data, along with ancillary wind and wave slope variance estimates, are used alongside existing theory to evaluate the extent of long-versus short-wave, O( cm), control of the bias. The longer wave bias contribution to the total EM bias is shown to range from 25 to as much as 100%. Moreover, on average the term is linearly related to wind speed and to the gravity wave slope variance, consistent with WNL theory. The EM bias associated with interactions between long and short waves is obtained assuming the effect is additive to the independently observed long-wave factor. This second component is also a substantial contributor, is observed to be quadratic in wind speed or wave slope, and dominates at moderate wind speeds. The behavior is shown to be consistent with EM bias prediction based in hydrodynamic modulation theory. Study implications for improved correction of the on-orbit satellite sea state bias are discussed. C1 NASA, Goddard Space Flight Ctr, Biospher & Hydrospher Lab, Wallops Isl, VA 23337 USA. IFREMER, Ctr Brest, DRO OS, F-29280 Plouzane, France. Univ Miami, Rosenstiel Sch Marine Sci, Miami, FL 33149 USA. Univ New Hampshire, Ocean Proc Anal Lab, Durham, NH 03824 USA. CNRS, Inst Rech Phenomenes Hors Equilibre, Marseille, France. RP Vandemark, D (reprint author), NASA, Goddard Space Flight Ctr, Biospher & Hydrospher Lab, Bldg N-159, Wallops Isl, VA 23337 USA. EM douglas.vandemark@nasa.gov; bertrand.chapron@ifremer.fr; telfouhaily@rsmas.miami.edu; janet.campbell@unh.edu RI Chapron, Bertrand/O-6527-2015 NR 29 TC 9 Z9 9 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-OCEANS JI J. Geophys. Res.-Oceans PD NOV 9 PY 2005 VL 110 IS C11 AR C11006 DI 10.1029/2005JC002979 PG 12 WC Oceanography SC Oceanography GA 985DP UT WOS:000233356600002 ER PT J AU Rosenfield, JE Schoeberl, MR AF Rosenfield, JE Schoeberl, MR TI Recovery of the tropical lower stratospheric ozone layer SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID IMPACT AB Long-term time dependent simulations out to the year 2050 using the Goddard Space Flight Center interactive 2D chemistry-radiation-dynamics model are used to predict tropical lower stratospheric ozone. The model results show that when chlorine levels are enhanced, heterogeneous chemistry on the surfaces of middle and high latitude sulfate aerosols and polar stratospheric clouds induces circulation changes which lead to ozone depletion in the tropical lower stratosphere. We find that despite a return to background chlorine levels, the tropical lower stratospheric ozone layer will not recover because of a reduction in penetrating ultraviolet radiation. This reduction is due to the faster upper stratospheric ozone recovery with increasing carbon dioxide. With background aerosol amounts, tropical ozone at 50 hPa is reduced by similar to 2% between 1980 and 1997 and remains at that level of depletion out to 2050. The simulations also suggest that tropical tropopause temperatures will be lowered by a maximum of 0.1 K between 1980 and 2015, resulting in a maximum reduction of tropical lower stratospheric water vapor of 2% between 1980 and 2018. These results may have important implications for recovery detection strategies. C1 Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21250 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Rosenfield, JE (reprint author), Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, 1000 Hilltop Circle, Baltimore, MD 21250 USA. EM rose@euterpe.gsfc.nasa.gov NR 12 TC 5 Z9 5 U1 0 U2 2 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 NOV 8 PY 2005 VL 32 IS 21 AR L21806 DI 10.1029/2005GL023626 PG 3 WC Geosciences, Multidisciplinary SC Geology GA 985CO UT WOS:000233353900002 ER PT J AU Novakov, T Menon, S Kirchstetter, TW Koch, D Hansen, JE AF Novakov, T Menon, S Kirchstetter, TW Koch, D Hansen, JE TI Aerosol organic carbon to black carbon ratios: Analysis of published data and implications for climate forcing SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID CHEMICAL-CHARACTERIZATION; PARTICULATE MATTER; ATMOSPHERIC AEROSOLS; SEASONAL-VARIATION; ELEMENTAL CARBON; BACKGROUND SITES; FINE PARTICLES; INDIAN-OCEAN; SOUTH-KOREA; HONG-KONG AB [1] Measurements of organic carbon (OC) and black carbon (BC) concentrations over a variety of locations worldwide have been analyzed to infer the spatial distributions of the ratios of OC to BC. Since these ratios determine the relative amounts of scattering and absorption, they are often used to estimate the radiative forcing due to aerosols. An artifact in the protocol for filter measurements of OC has led to widespread overestimates of the ratio of OC to BC in atmospheric aerosols. We developed a criterion to correct for this artifact and analyze corrected OC to BC ratios. The OC to BC ratios, ranging from 1.3 to 2.4, appear relatively constant and are generally unaffected by seasonality, sources, or technology changes, at the locations considered here. The ratios compare well with emission inventories over Europe and China but are a factor of 2 lower in other regions. The reduced estimate for OC/BC in aerosols strengthens the argument that reduction of soot emissions maybe a useful approach to slow global warming. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. Columbia Univ, Ctr Climate Syst Res, New York, NY 10025 USA. NASA, Goddard Inst Space Studies, New York, NY 10025 USA. Columbia Univ, Earth Inst, New York, NY USA. RP Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. EM tnovakov@lbl.gov NR 76 TC 69 Z9 71 U1 1 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 NOV 8 PY 2005 VL 110 IS D21 AR D21205 DI 10.1029/2005JD005977 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 985DA UT WOS:000233355100005 ER PT J AU Zhang, S Penner, JE Torres, O AF Zhang, S Penner, JE Torres, O TI Inverse modeling of biomass burning emissions using Total Ozone Mapping Spectrometer aerosol index for 1997 SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID OPTICAL-PROPERTIES; FOREST-FIRES; 3-DIMENSIONAL MODEL; CARBON EMISSIONS; SAHARAN DUST; DISTRIBUTIONS; TRANSPORT; SATELLITE; CO; DEPOSITION AB [1] We present results from an inverse model study to determine biomass smoke emissions for the year 1997 by comparison of modeled aerosol index ( AI) with that measured by the EP TOMS instrument. The IMPACT model with Data Assimilation Office (DAO) meteorology data in 1997 is utilized to obtain aerosol spatial and temporal distributions. Then a radiative transfer model is applied to generate the modeled AI. A Bayesian inverse technique is applied to optimize the difference between the modeled AI and the EP TOMS AI in the same period by regulating monthly a priori biomass smoke emissions in seven predefined regions. The modeled AI with a posteriori emissions is generally in better agreement with the EP TOMS AI. The a posteriori emissions from Indonesia increase by a factor of 8 - 10 over the a priori emissions due to the Indonesian fires in 1997. The annual total a posteriori source increases by about 13% for the year 1997 (6.31 Tg/yr black carbon and 67.27 Tg/yr smoke) in the base scenario, with a larger adjustment of monthly emissions. The sensitivity of this result to the a priori uncertainties, the height of the smoke layer, the cloud screening criteria, the inclusion of an adjustment of emissions outside the main biomass burning regions, and the inclusion of the covariances between observations in different locations is discussed in a set of sensitivity scenarios. The sensitivity scenarios suggest that the inverse model results are most sensitive to the assumed uncertainty for a priori emissions and the altitude of aerosol layer in the model and are less sensitive to other factors. In the scenario where the uncertainty of a priori emissions is increased to 100% (300% in Indonesia), the total annual black carbon emission is increased to 6.87 Tg/yr, and the smoke emission increases to 73.39 Tg/yr. The a posteriori emissions in Indonesia in the scenario with increased uncertainty are in better agreement with both the TOMS AI and with previous estimates for the Indonesian fires in 1997. In the scenario where biomass smoke from large fires are elevated by 1 km in altitude, the annual total black carbon emissions are 5.68 Tg/yr, and the smoke emissions are 60.44 Tg/yr, almost unchanged from the a priori emissions. C1 NASA, Goddard Inst Space Studies, New York, NY 10025 USA. MIT, Dept Earth Atmosphere & Planetary Sci, Cambridge, MA 02139 USA. Univ Michigan, Dept Atmospher Ocean & Space Sci, Ann Arbor, MI 48109 USA. Univ Maryland Baltimore Cty, Joint Ctr Earth Syst Technol, Baltimore, MD 21250 USA. RP NASA, Goddard Inst Space Studies, New York, NY 10025 USA. EM szhang@giss.nasa.gov; penner@mail.umich.edu RI Penner, Joyce/J-1719-2012; Torres, Omar/G-4929-2013 NR 80 TC 23 Z9 23 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 NOV 8 PY 2005 VL 110 IS D21 AR D21306 DI 10.1029/2004JD005738 PG 21 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 985DA UT WOS:000233355100002 ER PT J AU Ambur, DR Hasanyan, D Librescu, L Qin, ZM AF Ambur, DR Hasanyan, D Librescu, L Qin, ZM TI Diffraction of harmonic flexural waves in a cracked elastic plate carrying electrical current SO PROCEEDINGS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES LA English DT Article DE diffraction; through crack; magnetoelastic plate; flexural waves; singular integral equations; bending moment intensity factor ID UNIFORM MAGNETIC-FIELD; SCATTERING; FOUNDATION; VIBRATION; SURFACE; FLAT AB The scattering effect of harmonic flexural waves at a through crack in an elastic plate carrying electrical current is investigated. In this context, the Kirchhoffean bending plate theory is extended as to include magnetoelastic interactions. An incident wave giving rise to bending moments symmetric about the longitudinal x-axis of the crack is applied. Fourier transform technique reduces the problem to dual integral equations, which are then cast to a system of two singular integral equations. Efficient numerical computation is implemented to get the bending moment intensity factor for arbitrary frequency of the incident wave and of arbitrary electrical current intensity. The asymptotic behaviour of the bending moment intensity factor is analysed and parametric studies are conducted. C1 NASA Glenn Res Ctr, Struct Div, Cleveland, OH 44135 USA. Virginia Polytech Inst & State Univ, Dept Engn Sci & Mech, Blacksburg, VA 24061 USA. RP Ambur, DR (reprint author), NASA Glenn Res Ctr, Struct Div, MS 49-6,21000 Brookpark Rd, Cleveland, OH 44135 USA. EM zqin@vt.edu NR 27 TC 0 Z9 0 U1 0 U2 0 PU ROYAL SOCIETY PI LONDON PA 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 1364-5021 J9 P ROY SOC A-MATH PHY JI Proc. R. Soc. A-Math. Phys. Eng. Sci. PD NOV 8 PY 2005 VL 461 IS 2063 BP 3543 EP 3560 DI 10.1098/rspa.2005.1512 PG 18 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 976FT UT WOS:000232719000010 ER PT J AU Roulier, R Humeau, A Flatley, TP Abraham, P AF Roulier, R Humeau, A Flatley, TP Abraham, P TI Comparison between Hilbert-Huang transform and scalogram methods on non-stationary biomedical signals: application to laser Doppler flowmetry recordings SO PHYSICS IN MEDICINE AND BIOLOGY LA English DT Article ID CUTANEOUS VASODILATOR RESPONSE; PRESSURE-INDUCED VASODILATION; SKIN BLOOD-FLOW; DIABETIC SUBJECTS; INVOLVEMENT; HEALTHY; STRAIN AB A significant transient increase in laser Doppler flowmetry (LDF) signals is observed in response to a local and progressive cutaneous pressure application on healthy subjects. This reflex may be impaired in diabetic patients. The work presents a comparison between two signal processing methods that provide a clarification of this phenomenon. Analyses by the scalogram and the Hilbert-Huang transform (HHT) of LDF signals recorded at rest and during a local and progressive cutaneous pressure application are performed on healthy and type 1 diabetic subjects. Three frequency bands, corresponding to myogenic, neurogenic and endothelial related metabolic activities, are studied at different time intervals in order to take into account the dynamics of the phenomenon. The results show that both the scalogram and the HHT methods lead to the same conclusions concerning the comparisons of the myogenic, neurogenic and endothelial related metabolic activities-during the progressive pressure and at rest-in healthy and diabetic subjects. However, the HHT shows more details that may be obscured by the scalogram. Indeed, the non-locally adaptative limitations of the scalogram can remove some definition from the data. These results may improve knowledge on the above-mentioned reflex as well as on non-stationary biomedical signal processing methods. C1 ESAIP, Grp ISAIP, F-49180 St Barthelemy Anjou, France. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Ctr Hosp Univ Angers, Lab Physiol & Explorat Vasc, F-49033 Angers, France. RP Humeau, A (reprint author), ESAIP, Grp ISAIP, 18 Rue 8 Mai 1945,BP 80022, F-49180 St Barthelemy Anjou, France. EM ahumeau@isaip.uco.fr NR 14 TC 4 Z9 4 U1 0 U2 7 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0031-9155 J9 PHYS MED BIOL JI Phys. Med. Biol. PD NOV 7 PY 2005 VL 50 IS 21 BP 5189 EP 5202 DI 10.1088/0031-9155/50/21/016 PG 14 WC Engineering, Biomedical; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Radiology, Nuclear Medicine & Medical Imaging GA 991EJ UT WOS:000233794800016 PM 16237249 ER PT J AU Schoeberl, MR Douglass, AR Polansky, B Boone, C Walker, KA Bernath, P AF Schoeberl, MR Douglass, AR Polansky, B Boone, C Walker, KA Bernath, P TI Estimation of stratospheric age spectrum from chemical tracers SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ARRAY ETALON SPECTROMETER; HALOGEN OCCULTATION EXPERIMENT; TROPICAL STRATOSPHERE; GENERAL-CIRCULATION; MEAN AGES; TRANSPORT; MODEL; VALIDATION; UARS; AIR AB We have developed a technique to diagnose the stratospheric age spectrum and estimate the mean age of air using the distributions of at least four constituents with different photochemical lifetimes. We demonstrate the technique using a 3-D CTM and then apply the technique to OMS tropical balloon observations, UARS CLAES January 1993, and ACE February-March 2005 observations of CFC11, CFC12, CH4, and N2O. Our results using the ACE and OMS data are generally in agreement with mean age of air estimates from the chemical model and from observations of SF6 and CO2; however, the UARS-derived mean age estimates show an intrusion of very young tropical air into the midlatitude stratosphere. The UARS CLAES values of F11 and F12 appear to be significantly higher than ACE and model values and bias our lower-stratospheric estimates of the age derived from UARS data toward younger values. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Sci Syst Applicat Inc, Lanham, MD 20706 USA. Univ Waterloo, Dept Chem, Waterloo, ON N2L 3G1, Canada. RP NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM mark.r.schoeberl@nasa.gov RI Bernath, Peter/B-6567-2012; Douglass, Anne/D-4655-2012 OI Bernath, Peter/0000-0002-1255-396X; NR 29 TC 25 Z9 26 U1 0 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 NOV 4 PY 2005 VL 110 IS D21 AR D21303 DI 10.1029/2005JD006125 PG 18 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 982LY UT WOS:000233161100004 ER PT J AU Howard, AD Moore, JM Irwin, RP AF Howard, AD Moore, JM Irwin, RP TI An intense terminal epoch of widespread fluvial activity on early Mars: 1. Valley network incision and associated deposits SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID DRAINAGE-BASIN EVOLUTION; MARGARITIFER SINUS; MARTIAN HIGHLANDS; NORTHERN PLAINS; CRATER LAKES; ORIGIN; REGION; WATER; PRECIPITATION; GROUNDWATER AB We present evidence that a final epoch of widespread fluvial erosion and deposition in the cratered highlands during the latest Noachian or early to mid-Hesperian was characterized by integration of flow within drainage networks as long as 4000 km and trunk valley incision of 50 to 350 m into earlier Noachian depositional basins. Locally deltaic sediments were deposited where incised valley systems debouched into basins. Large alluvial fans of sediment deposited from erosion of alcoves in steep crater walls probably formed contemporaneously. The depth of incision below Noachian surfaces correlates strongly with the gradient and the total valley length, suggesting consistent regional hydrology. Estimated discharges from channel dimensions indicate flow rates equivalent to mean annual floods in terrestrial drainage basins of equivalent size. Such high flow rates imply either runoff directly from precipitation or rapid melting of accumulated snow. Development of duricrusts on the Noachian landscape may have contributed to focusing of late-stage erosion within major trunk drainages. This late-stage epoch of intense fluvial activity appears to be fundamentally different than the fluvial environment prevailing during most of the Noachian Period, which was characterized by widespread fluvial erosion of highlands and crater rims, deeply infilling crater floors, and intercrater basins through ephemeral fluvial activity, and development of local rather than regionally integrated drainage networks. C1 Univ Virginia, Dept Environm Sci, Charlottesville, VA 22904 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Smithsonian Inst, Natl Air & Space Museum, Ctr Earth & Planetary Studies, Washington, DC 20013 USA. RP Howard, AD (reprint author), Univ Virginia, Dept Environm Sci, POB 400123, Charlottesville, VA 22904 USA. EM ah6p@virginia.edu; jeff.moore@nasa.gov; irwinr@si.edu OI Howard, Alan/0000-0002-5423-1600 NR 77 TC 108 Z9 110 U1 2 U2 6 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 NOV 4 PY 2005 VL 110 IS E12 AR E12S14 DI 10.1029/2005JE002459 PG 20 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 982MO UT WOS:000233162700002 ER PT J AU Yeomans, DK AF Yeomans, DK TI The planets SO SCIENCE LA English DT Book Review C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Yeomans, DK (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Donald.K.Yeomans@jpl.nasa.gov NR 1 TC 1 Z9 1 U1 1 U2 1 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 NOV 4 PY 2005 VL 310 IS 5749 BP 785 EP 785 DI 10.1126/science.1120240 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 981XR UT WOS:000233121800024 ER PT J AU Apai, D Pascucci, I Bouwman, J Natta, A Henning, T Dullemond, CP AF Apai, D Pascucci, I Bouwman, J Natta, A Henning, T Dullemond, CP TI The onset of planet formation on brown dwarf disks SO SCIENCE LA English DT Article ID STAR-FORMING REGION; T-TAURI STARS; GRAIN-GROWTH; POPULATION; SPECTRA AB The onset of planet formation in protoplanetary disks is marked by the growth and crystallization of sub-micrometer-sized dust grains accompanied by dust settling toward the disk mid-plane. Here, we present infrared spectra of disks around brown dwarfs and brown dwarf candidates. We show that all three processes occur in such cool disks in, a way similar or identical to that in disks around low- and intermediate-mass stars. These results indicate that the onset of planet formation extends to disks around brown dwarfs, suggesting that planet formation is a robust process occurring in most young circumstellar disks. C1 Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. NASA, Ames Res Ctr, NASA Astrobiol Inst, Moffett Field, CA 94035 USA. Max Planck Inst Astron, D-69117 Heidelberg, Germany. Osserv Astrofis Arcetri, Inst Nazl Astrofis, I-50125 Florence, Italy. RP Apai, D (reprint author), Univ Arizona, Steward Observ, 933 N Cherry Ave, Tucson, AZ 85721 USA. EM apai@as.arizona.edu NR 22 TC 140 Z9 141 U1 0 U2 5 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 NOV 4 PY 2005 VL 310 IS 5749 BP 834 EP 836 DI 10.1126/science.1118042 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 981XR UT WOS:000233121800039 PM 16239438 ER PT J AU Kashlinsky, A Arendt, RG Mather, J Moseley, SH AF Kashlinsky, A Arendt, RG Mather, J Moseley, SH TI Tracing the first stars with fluctuations of the cosmic infrared background SO NATURE LA English DT Article ID SPITZER-SPACE-TELESCOPE; PROBE WMAP OBSERVATIONS; ARRAY CAMERA IRAC; COBE DIRBE MAPS; 1ST STARS; EXPERIMENT SEARCH; MIDINFRARED OBSERVATIONS; HIGH-REDSHIFT; GALAXIES; MICRONS AB The deepest space- and ground-based observations find metal-enriched galaxies at cosmic times when the Universe was less than 1 Gyr old. These stellar populations had to be preceded by the metal-free first stars, known as 'population III'. Recent cosmic microwave background polarization measurements indicate that stars started forming early - when the Universe was <= 200 Myr old. It is now thought that population III stars were significantly more massive than the present metal-rich stellar populations. Although such sources will not be individually detectable by existing or planned telescopes, they would have produced significant cosmic infrared background radiation in the near-infrared, whose fluctuations reflect the conditions in the primordial density field. Here we report a measurement of diffuse flux fluctuations after removing foreground stars and galaxies. The anisotropies exceed the instrument noise and the more local foregrounds; they can be attributed to emission from population III stars, at an era dominated by these objects. C1 Observat Cosmol Lab, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. SSAI, Greenbelt, MD 20771 USA. RP Observat Cosmol Lab, Greenbelt, MD 20771 USA. EM kashlinsky@stars.gsfc.nasa.gov RI Moseley, Harvey/D-5069-2012; OI Arendt, Richard/0000-0001-8403-8548 NR 49 TC 111 Z9 111 U1 0 U2 1 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 NOV 3 PY 2005 VL 438 IS 7064 BP 45 EP 50 DI 10.1038/nature04143 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 979XS UT WOS:000232979000037 PM 16267547 ER PT J AU Schutz, BE Zwally, HJ Shuman, CA Hancock, D DiMarzio, JP AF Schutz, BE Zwally, HJ Shuman, CA Hancock, D DiMarzio, JP TI Overview of the ICESat Mission SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article AB The Geoscience Laser Altimeter System (GLAS) on the NASA Ice, Cloud and land Elevation Satellite (ICESat) has provided a view of the Earth in three dimensions with unprecedented accuracy. Although the primary objectives focus on polar ice sheet mass balance, the GLAS measurements, distributed in 15 science data products, have interdisciplinary application to land topography, hydrology, vegetation canopy heights, cloud heights and atmospheric aerosol distributions. Early laser life issues have been mitigated with the adoption of 33-day operation periods, three times per year, designed to document intra- and inter-annual polar ice changes in accordance with mission requirements. A variety of calibration/validation experiments have been executed which show that the elevation products, when fully calibrated, have an accuracy that meets the science requirements. The series of papers in this special ICESat issue demonstrate the utility and quality of the ICESat data. C1 Univ Texas, Ctr Space Res, Austin, TX 78759 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Schutz, BE (reprint author), Univ Texas, Ctr Space Res, Austin, TX 78759 USA. EM schutz@utcsr.ae.utexas.edu NR 10 TC 290 Z9 312 U1 6 U2 33 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 NOV 2 PY 2005 VL 32 IS 21 AR L21S01 DI 10.1029/2005GL024009 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 982LI UT WOS:000233159400006 ER PT J AU Lu, LX Denning, AS da Silva-Dias, MA da Silva-Dias, P Longo, M Freitas, SR Saatchi, S AF Lu, LX Denning, AS da Silva-Dias, MA da Silva-Dias, P Longo, M Freitas, SR Saatchi, S TI Mesoscale circulations and atmospheric CO2 variations in the Tapajos Region, Para, Brazil SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID CARBON-DIOXIDE; ARCTIC STRATUS; SOUTH FLORIDA; LAND-USE; CLIMATE; IMPACT; WEATHER; MODELS; RAMS; PARAMETERIZATION AB We have investigated mesoscale circulations and atmospheric CO2 variations over a heterogeneous landscape of forests, pastures, and large rivers during the Santarem Mesoscale Campaign (SMC) of August 2001. The atmospheric CO2 concentration variations were simulated using the Colorado State University Regional Atmospheric Modeling System with four nested grids that included a 1-km finest grid centered on the Tapajos National Forest. Surface CO2 fluxes were prescribed using idealized diurnal cycles over forest and pasture that derived from flux tower observations; while surface water CO2 efflux was prescribed using a value suggested by in situ measurements in the Amazon region. Our simulation ran from 1 August through 15 August 2001, which was concurrent with the SMC. Evaluation against flux tower observations and Belterra meteorological tower measurements showed that the model captured the observed 2-m temperatures and 10-m winds reasonably well. At 57 m the model reproduced the daytime CO2 concentration better than the nighttime concentration but missed the observed early morning CO2 maxima, in part because of the difficulties of simulating stable nocturnal boundary conditions and subgrid-scale intracanopy processes. The results also suggested that the topography, the differences in roughness length between water and land, the "T'' shape juxtaposition of Amazon and Tapajos Rivers, and the resulting horizontal and vertical wind shears all facilitated the generation of local mesoscale circulations. Possible mechanisms producing a low-level convergence (LLC) line near the east bank of the Tapajos River were explored. Under strong trade wind conditions, mechanical forcing is more important than thermal forcing in LLC formation. Persistent clouds near the east side of the Tapajos River may have a significant impact on observed ecosystem carbon flux and should be taken into account if tower fluxes are to be generalized to a larger region. C1 Colorado State Univ, Dept Atmospher Sci, Ft Collins, CO 80525 USA. Univ Sao Paulo, Dept Atmospher Sci, BR-05508900 Sao Paulo, Brazil. Natl Inst Space Res, Ctr Weather Forecasting & Climate Studies, BR-12630000 Cachoeira Paulista, Brazil. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Lu, LX (reprint author), Colorado State Univ, Dept Atmospher Sci, Ft Collins, CO 80525 USA. EM lixin@atmos.colostate.edu RI Denning, Scott/F-4974-2011; Freitas, Saulo/A-2279-2012; Longo, Marcos/F-5033-2014 OI Denning, Scott/0000-0003-3032-7875; Freitas, Saulo/0000-0002-9879-646X; Longo, Marcos/0000-0001-5062-6245 NR 58 TC 21 Z9 23 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 NOV 2 PY 2005 VL 110 IS D21 AR D21102 DI 10.1029/2004JD005757 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 982LT UT WOS:000233160600001 ER PT J AU Gascoin, F Ottensmann, S Stark, D Haile, SM Snyder, GJ AF Gascoin, F Ottensmann, S Stark, D Haile, SM Snyder, GJ TI Zintl phases as thermoelectric materials: Tuned transport properties of the compounds CaxYb1-xZn2Sb2 SO ADVANCED FUNCTIONAL MATERIALS LA English DT Article ID CLATHRATE COMPOUND; SEMICONDUCTOR; ZN4SB3 AB Zintl phases are ideal candidates for efficient thermoelectric materials, because they are typically small-bandgap semiconductors with complex structures. Furthermore, such phases allow fine adjustment of dopant concentration without disrupting electronic mobility, which is essential for optimizing thermoelectric material efficiency. The tunability of Zintl phases is demonstrated with the series CaxYb1-xZn2Sb2 (0 <= x <= 1). Measurements of the electrical conductivity, Hall mobility, Seebeck coefficient, and thermal conductivity (in the 300-800 K temperature range) show the compounds to behave as heavily doped semiconductors, with transport properties that can be systematically regulated by varying x. Within this series, x = 0 is the most metallic (lowest electrical resistivity, lowest Seebeck coefficient, and highest carrier concentration), and x = 1 is the most semiconducting (highest electrical resistivity, highest Seebeck coefficient, and lowest carrier concentration), while the mobility is largely independent of x. In addition, the structural disorder generated by the incorporation of multiple cations lowers the overall thermal conductivity significantly at intermediate compositions, increasing the thermoelectric figure of merit, zT Thus, both zT and the thermoelectric compatibility factor (like zT, a composite function of the transport properties) can be finely tuned to allow optimization of efficiency in a thermoelectric device. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,Mail Stop 277-207, Pasadena, CA 91109 USA. EM fgascoin@caltech.edu RI Snyder, G. Jeffrey/E-4453-2011; Snyder, G/I-2263-2015; Haile, Sossina/I-3448-2015 OI Snyder, G. Jeffrey/0000-0003-1414-8682; NR 24 TC 194 Z9 197 U1 10 U2 99 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA POSTFACH 101161, 69451 WEINHEIM, GERMANY SN 1616-301X EI 1616-3028 J9 ADV FUNCT MATER JI Adv. Funct. Mater. PD NOV PY 2005 VL 15 IS 11 BP 1860 EP 1864 DI 10.1002/adfm.200500043 PG 5 WC Chemistry, Multidisciplinary; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 984CG UT WOS:000233279500018 ER PT J AU Liao, L Meneghini, R AF Liao, L Meneghini, R TI A study of air/space-borne dual-wavelength radar for estimation of rain profiles SO ADVANCES IN ATMOSPHERIC SCIENCES LA English DT Article DE rain rate; dual-wavelength radar; raindrop size distribution; and GPM ID PATH ATTENUATION; REFLECTIVITY; SNOWFLAKES; SNOWFALL; MODEL; SIZE AB In this study, a framework is given by which air/space-borne dual-wavelength radar data can be used to estimate the characteristic parameters of hydrometeors. The focus of the study is on the Global Precipitation Measurement (GPM) precipitation radar, a dual-wavelength radar that will operate in the Ku (13.6 GHz) and Ka (35 GHz) bands. A key aspect of the retrievals is the relationship between the differential frequency ratio (DFR) and the median volume diameter, D-0, and its dependence on the phase state of the hydrometeors. It is shown that parametric plots of D-0 and particle concentration in the plane of the DFR and the radar reflectivity factor in the Ku band can be used to reduce the ambiguities in deriving D-0 from DFR. A self-consistent iterative algorithm, which does not require the use of an independent path-attenuation constraint, is examined by applying it to the apparent radar reflectivity profiles simulated from a drop size distribution (DSD) model. For light to moderate rain, the self-consistent rain profiling approach converges to the correct solution only if the same shape factor of the Gamma distributions is used both to generate and retrieve the rain profiles. On the other hand, if the shape factors differ, the iteration generally converges but not to the correct solution. To further examine the dual-wavelength techniques, the self-consistent iterative algorithm, along with forward and backward rain profiling algorithms, are applied to measurements taken from the 2nd generation Precipitation Radar (PR-2) built by the Jet Propulsion Laboratory. Consistent with the model results, it is found that the estimated rain profiles are sensitive to the shape factor of the size distribution when the iterative, self-consistent approach is used but relatively insensitive to this parameter when the forward- and backward-constrained approaches are used. C1 Goddard Earth Sci & Technol Ctr, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Goddard Earth Sci & Technol Ctr, Caelum, Greenbelt, MD 20771 USA. EM lliao@neptune.gsfc.nasa.gov RI AAS, AAS/C-2949-2014 NR 18 TC 14 Z9 14 U1 0 U2 1 PU SCIENCE PRESS PI BEIJING PA 16 DONGHUANGCHENGGEN NORTH ST, BEIJING 100717, PEOPLES R CHINA SN 0256-1530 EI 1861-9533 J9 ADV ATMOS SCI JI Adv. Atmos. Sci. PD NOV PY 2005 VL 22 IS 6 BP 841 EP 851 DI 10.1007/BF02918684 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 987CS UT WOS:000233496600008 ER PT J AU Yang, S Smith, EA AF Yang, S Smith, EA TI Resolving SSM/I-ship radar rainfall discrepancies from AIP-3 SO ADVANCES IN ATMOSPHERIC SCIENCES LA English DT Article DE rainfall; SSM/I; radar; satellite microwave measurements ID MICROWAVE BRIGHTNESS TEMPERATURES; PHYSICAL PRECIPITATION RETRIEVAL; SPATIAL-RESOLUTION ENHANCEMENT; CLOUD-RADIATION MODEL; TOGA COARE; SATELLITE MEASUREMENTS; PROFILING ALGORITHM; INTERCOMPARISON PROJECT; CONVECTIVE RAINFALL; TRMM AB The third algorithm intercomparison project (AIP-3) involved rain estimates from more than 50 satellite rainfall algorithms and ground radar measurements within the Intensive Flux Array (IFA) over the equatorial western Pacific warm pool region during the Tropical Ocean Global Atmosphere coupled Ocean-Atmosphere Response Experiment (TOGA COARE). Early results indicated that there was a systematic bias between rainrates from satellite passive microwave and ground radar measurements. The mean rainrate from radar measurements is about 50% underestimated compared to that from passive microwave-based retrieval algorithms. This paper is designed to analyze rain patterns from the Florida State University rain retrieval algorithm and radar measurements to understand physically the rain discrepancies. Results show that there is a clear range-dependent bias associated with the radar measurements. However, this range-dependent systematical bias is almost eliminated with the corrected radar rainrates. Results suggest that the effects from radar attenuation correction, calibration and beam filling are the major sources of rain discrepancies. This study demonstrates that rain retrievals based on satellite measurements from passive microwave radiometers such as the Special Sensor of Microwave Imager (SSM/I) are reliable, while rain estimates from ground radar measurements are correctable. C1 George Mason Univ, Sch Computat Sci, Fairfax, VA 22030 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Yang, S (reprint author), George Mason Univ, Sch Computat Sci, Fairfax, VA 22030 USA. EM ysong@agnes.gsfc.nasa.gov RI AAS, AAS/C-2949-2014 NR 41 TC 2 Z9 2 U1 0 U2 1 PU SCIENCE PRESS PI BEIJING PA 16 DONGHUANGCHENGGEN NORTH ST, BEIJING 100717, PEOPLES R CHINA SN 0256-1530 J9 ADV ATMOS SCI JI Adv. Atmos. Sci. PD NOV PY 2005 VL 22 IS 6 BP 903 EP 914 DI 10.1007/BF02918689 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 987CS UT WOS:000233496600013 ER PT J AU Turyshev, SG Nieto, MM Anderson, JD AF Turyshev, SG Nieto, MM Anderson, JD TI Study of the Pioneer anomaly: A problem set SO AMERICAN JOURNAL OF PHYSICS LA English DT Article ID LONG-RANGE ACCELERATION; ULYSSES DATA; PROSAIC EXPLANATION; DISTANT SPACECRAFT; GALILEO; WEAK AB Analysis of the radio-metric tracking data from the Pioneer 10 and 11 spacecraft at distances between 20 and 70 astronomical units from the Sun has consistently indicated the presence of an anomalous, small, and constant Doppler frequency drift. The drift is a blueshift, uniformly changing at the rate of (5.99 +/- 0.01) x 10(-9) Hz/s. The signal also can be interpreted as a constant acceleration of each spacecraft of (8.74 +/- 1.33) x 10(-8) cm/s(2) directed toward the Sun. This interpretation has become known as the Pioneer anomaly. We provide a problem set based on the detailed investigation of this anomaly, the nature of which remains unexplained. (c) 2005 American Association of Physics Teachers. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Turyshev, SG (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM turyshev@jpl.nasa.gov; mmn@lanl.gov; john.d.anderson@jpl.nasa.gov NR 24 TC 23 Z9 23 U1 0 U2 0 PU AMER ASSOC PHYSICS TEACHERS AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 0002-9505 EI 1943-2909 J9 AM J PHYS JI Am. J. Phys. PD NOV PY 2005 VL 73 IS 11 BP 1033 EP 1044 DI 10.1119/1.2008300 PG 12 WC Education, Scientific Disciplines; Physics, Multidisciplinary SC Education & Educational Research; Physics GA 980CJ UT WOS:000232991200009 ER PT J AU Stewart, JM Medow, MS Montgomery, LD Glover, JL Millonas, MM AF Stewart, JM Medow, MS Montgomery, LD Glover, JL Millonas, MM TI Splanchnic hyperemia and hypervolemia during Valsalva maneuver in postural tachycardia syndrome SO AMERICAN JOURNAL OF PHYSIOLOGY-HEART AND CIRCULATORY PHYSIOLOGY LA English DT Article DE vasoconstriction; splanchnic arterial resistance; mesenteric artery; autonomic dysfunction; orthostatic intolerance ID THORACIC BLOOD-VOLUME; MESENTERIC-ARTERY; SYNDROME POTS; ORTHOSTATIC INTOLERANCE; MENSTRUAL-CYCLE; NITRIC-OXIDE; FLOW; IMPEDANCE; PRESSURE; SYSTEM AB Prior work demonstrated dependence of the change in blood pressure during the Valsalva maneuver (VM) on the extent of thoracic hypovolemia and splanchnic hypervolemia. Thoracic hypovolemia and splanchnic hypervolemia characterize certain patients with postural tachycardia syndrome ( POTS) during orthostatic stress. These patients also experience abnormal phase II hypotension and phase IV hypertension during VM. We hypothesize that reduced splanchnic arterial resistance explains aberrant VM results in these patients. We studied 17 POTS patients aged 15-23 yr with normal resting peripheral blood flow by strain gauge plethysmography and 10 comparably aged healthy volunteers. All had normal blood volumes by dye dilution. We assessed changes in estimated thoracic, splanchnic, pelvic-thigh, and lower leg blood volume and blood flow by impedance plethysmography throughout VM performed in the supine position. Baseline splanchnic blood flow was increased and calculated arterial resistance was decreased in POTS compared with control subjects. Splanchnic resistance decreased and flow increased in POTS subjects, whereas splanchnic resistance increased and flow decreased in control subjects during stage II of VM. This was associated with increased splanchnic blood volume, decreased thoracic blood volume, increased heart rate, and decreased blood pressure in POTS. Pelvic and leg resistances were increased above control and remained so during stage IV of VM, accounting for the increased blood pressure overshoot in POTS. Thus splanchnic hyperemia and hypervolemia are related to excessive phase II blood pressure reduction in POTS despite intense peripheral vasoconstriction. Factors other than autonomic dysfunction may play a role in POTS. C1 New York Med Coll, Div Res, Dept Pediat, Hawthorne, NY 10532 USA. New York Med Coll, Hypotens Lab, Hawthorne, NY 10532 USA. New York Med Coll, Dept Physiol, Hawthorne, NY 10532 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Stewart, JM (reprint author), New York Med Coll, Div Res, Dept Pediat, Suite 3050,19 Bradhurst Ave, Hawthorne, NY 10532 USA. EM stewart@nymc.edu FU NHLBI NIH HHS [1R01-HL-66007, 1R01-HL-074873, R01 HL066007, R01 HL074873]; NINDS NIH HHS [R21 NS094644] NR 39 TC 6 Z9 6 U1 0 U2 0 PU AMER PHYSIOLOGICAL SOC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0363-6135 J9 AM J PHYSIOL-HEART C JI Am. J. Physiol.-Heart Circul. Physiol. PD NOV PY 2005 VL 289 IS 5 BP H1951 EP H1959 DI 10.1152/ajpheart.00194.2005 PG 9 WC Cardiac & Cardiovascular Systems; Physiology; Peripheral Vascular Disease SC Cardiovascular System & Cardiology; Physiology GA 973BI UT WOS:000232497500023 PM 15964926 ER PT J AU Shvedova, AA Kisin, ER Mercer, R Murray, AR Johnson, VJ Potapovich, AI Tyurina, YY Gorelik, O Arepalli, S Schwegler-Berry, D Hubbs, AF Antonini, J Evans, DE Ku, BK Ramsey, D Maynard, A Kagan, VE Castranova, V Baron, P AF Shvedova, AA Kisin, ER Mercer, R Murray, AR Johnson, VJ Potapovich, AI Tyurina, YY Gorelik, O Arepalli, S Schwegler-Berry, D Hubbs, AF Antonini, J Evans, DE Ku, BK Ramsey, D Maynard, A Kagan, VE Castranova, V Baron, P TI Unusual inflammatory and fibrogenic pulmonary responses to single-walled carbon nanotubes in mice SO AMERICAN JOURNAL OF PHYSIOLOGY-LUNG CELLULAR AND MOLECULAR PHYSIOLOGY LA English DT Article DE nanoparticles; inflammation; cytokines; microbial infection ID INTRATRACHEAL INSTILLATION; PARTICLES; TOXICITY; EXPOSURE; LUNG; RATS; ALVEOLAR; MONOXIDE; TISSUE AB Single-walled carbon nanotubes (SWCNT) are new materials of emerging technological importance. As SWCNT are introduced into the life cycle of commercial products, their effects on human health and environment should be addressed. We demonstrated that pharyngeal aspiration of SWCNT elicited unusual pulmonary effects in C57BL/ 6 mice that combined a robust but acute inflammation with early onset yet progressive fibrosis and granulomas. A dose-dependent increase in the protein, LDH, and gamma-glutamyl transferase activities in bronchoalveolar lavage were found along with accumulation of 4-hydroxynonenal ( oxidative biomarker) and depletion of glutathione in lungs. An early neutrophils accumulation ( day 1), followed by lymphocyte ( day 3) and macrophage ( day 7) influx, was accompanied by early elevation of proinflammatory cytokines ( TNF-alpha, IL-1 beta; day 1) followed by fibrogenic transforming growth factor ( TGF)-beta 1 ( peaked on day 7). A rapid progressive fibrosis found in mice exhibited two distinct morphologies: 1) SWCNT-induced granulomas mainly associated with hypertrophied epithelial cells surrounding SWCNT aggregates and 2) diffuse interstitial fibrosis and alveolar wall thickening likely associated with dispersed SWCNT. In vitro exposure of murine RAW 264.7 macrophages to SWCNT triggered TGF-beta 1 production similarly to zymosan but generated less TNF-alpha and IL-1 beta. SWCNT did not cause superoxide or NO (.) production, active SWCNT engulfment, or apoptosis in RAW 264.7 macrophages. Functional respiratory deficiencies and decreased bacterial clearance ( Listeria monocytogenes) were found in mice treated with SWCNT. Equal doses of ultrafine carbon black particles or fine crystalline silica ( SiO(2)) did not induce granulomas or alveolar wall thickening and caused a significantly weaker pulmonary inflammation and damage. C1 NIOSH, Hlth Effects Lab Div, Morgantown, WV 26505 USA. NIOSH, Div Appl Res Technol, Cincinnati, OH 45226 USA. NASA, Lyndon B Johnson Space Ctr, Nanotube Team, GBTech Inc, Houston, TX 77058 USA. Univ Pittsburgh, Ctr Free Rad & Antioxidant Hlth, Pittsburgh, PA USA. Univ Pittsburgh, Dept Environm Hlth, Pittsburgh, PA USA. RP Shvedova, AA (reprint author), NIOSH, Hlth Effects Lab Div, Morgantown, WV 26505 USA. EM AShvedova@cdc.gov RI Johnson, Victor/A-7910-2009; Arepalli, Sivaram/A-5372-2010; Maynard, Andrew/D-1076-2010; OI Maynard, Andrew/0000-0003-2117-5128 FU NHLBI NIH HHS [1R01 HL-070755]; NIOSH CDC HHS [1R01 OH-008282] NR 29 TC 641 Z9 669 U1 7 U2 98 PU AMER PHYSIOLOGICAL SOC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 1040-0605 J9 AM J PHYSIOL-LUNG C JI Am. J. Physiol.-Lung Cell. Mol. Physiol. PD NOV PY 2005 VL 289 IS 5 BP L698 EP L708 DI 10.1152/ajplung.00084.2005 PG 11 WC Physiology; Respiratory System SC Physiology; Respiratory System GA 972RB UT WOS:000232469800003 PM 15951334 ER PT J AU Vogel, BF Venkateswaran, K Satomi, M Gram, L AF Vogel, BF Venkateswaran, K Satomi, M Gram, L TI Identification of Shewanella baltica as the most important H2S-producing species during iced storage of Danish marine fish SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID SP-NOV.; SP. NOV; SPOILAGE BACTERIA; PSEUDOMONAS-PUTREFACIENS; SHELF-LIFE; WATER; SEA; FRIGIDIMARINA; STRAINS; DEEP AB Shewanella putrefaciens has been considered the main spoilage bacteria of low-temperature stored marine seafood. However, psychrotropic Shewanella have been reclassified during recent years, and the purpose of the present study was to determine whether any of the new Shewanella species are important in fish spoilage. More than 500 H,S-producing strains were isolated from iced stored marine fish (cod, plaice, and flounder) caught in the Baltic Sea during winter or summer time. All strains were identified as Shewanella species by phenotypic tests. Different Shewanella species were present on newly caught fish. During the warm summer months the mesophilic human pathogenic S. algae dominated the H2S-producing bacterial population. After iced storage, a shift in the Shewanella species was found, and most of the H2S-producing strains were identified as S. baltica. The 16S rRNA gene sequence analysis confirmed the identification of these two major groups. Several isolates could only be identified to the genus Shewanella level and were separated into two subgroups with low (44%) and high (47%) G+C mol%. The low G+C% group was isolated during winter months, whereas the high G+C% group was isolated on fish caught during summer and only during the first few days of iced storage. Phenotypically, these strains were different from the type strains of S. putrefaciens, S. oneidensis, S. colwelliana, and S. affinis, but the high G+C% group clustered close to S. colwelliana by 16S rRNA gene sequence comparison. The low G+C% group may constitute a new species. S. baltica, and the low G+C% group of Shewanella spp. strains grew well in cod juice at 0 degrees C, but three high G+C Shewanella spp. were unable to grow at 0 degrees C. In conclusion, the spoilage reactions of iced Danish marine fish remain unchanged (i.e., trimethylamine-N-oxide reduction and H,S production); however, the main H2S-producing organism was identified as S. baltica. C1 CO Tech Univ Denmark, Dept Seafood Res, Danish Inst Fisheries Res, DK-2800 Lyngby, Denmark. CALTECH, Jet Prop Lab, Biotechnol & Planetary Protect Grp, Pasadena, CA 91109 USA. Fisheries Res Agcy, Natl Res Inst Fisheries Sci, Yokohama, Kanagawa 2368648, Japan. RP Vogel, BF (reprint author), CO Tech Univ Denmark, Dept Seafood Res, Danish Inst Fisheries Res, Soltofts Plads,Bldg 221, DK-2800 Lyngby, Denmark. EM bfv@dfu.min.dk NR 46 TC 69 Z9 79 U1 4 U2 20 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0099-2240 J9 APPL ENVIRON MICROB JI Appl. Environ. Microbiol. PD NOV PY 2005 VL 71 IS 11 BP 6689 EP 6697 DI 10.1128/AEM.71.11.6689-6697.2005 PG 9 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA 983IN UT WOS:000233225000029 ER PT J AU Vishnivetskaya, TA Kathariou, S AF Vishnivetskaya, TA Kathariou, S TI Putative transposases conserved in Exiguobacterium isolates from ancient Siberian permafrost and from contemporary surface habitats SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID SEQUENCE ALIGNMENT; SP-NOV; BACTERIA; MICROORGANISMS; DIVERSITY; SEDIMENTS AB Gram-positive bacteria of the genus Exiguobacterium have been repeatedly isolated from Siberian permafrost ranging in age from 20,000 to 2 to 3 million years and have been sporadically recovered from markedly diverse habitats, including microbial mats in Lake Fryxell (Antarctic), surface water, and food-processing environments. However, there is currently no information on genomic diversity of this microorganism or on the physiological strategies that have allowed its survival under prolonged freezing in the permafrost. Analysis of the genome sequence of the most ancient available Exiguobacterium isolate (Exiguobacterium sp. strain 255-15, from 2 to 3 million-year-old Siberian permafrost) revealed numerous putative transposase sequences, primarily of the IS200/IS605, IS30, and IS3 families, with four transposase families identified. Several of the transposase genes appeared to be part of insertion sequences. Southern blots with different transposase probes yielded high-resolution genomic fingerprints which differentiated the different permafrost isolates from each other and from the Exiguobacterium spp. type strains which have been derived from diverse surface habitats. Each of the Exiguohacterium sp. strain 255-15 transposases that were used as probes had highly conserved homologs in the genome of other Exiguobacterium strains, both from permafrost and from modern sites. These findings suggest that, prior to their entrapment in permafrost, Exiguobacterium isolates had acquired transposases and that conserved transposases are present in Exiguobacterium spp., which now can be isolated from various modern surface habitats. C1 N Carolina State Univ, NASA, Astrobiol Inst, Raleigh, NC 27695 USA. RP Vishnivetskaya, TA (reprint author), N Carolina State Univ, Dept Food Sci, Schaub Hall,Room 339, Raleigh, NC 27695 USA. EM tavishni@ncsu.edu RI Vishnivetskaya, Tatiana/A-4488-2008 OI Vishnivetskaya, Tatiana/0000-0002-0660-023X NR 25 TC 11 Z9 13 U1 1 U2 5 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0099-2240 J9 APPL ENVIRON MICROB JI Appl. Environ. Microbiol. PD NOV PY 2005 VL 71 IS 11 BP 6954 EP 6962 DI 10.1128/AEM.71.11.6954-6962.2005 PG 9 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA 983IN UT WOS:000233225000061 PM 16269730 ER PT J AU Provencal, R Gupta, M Owano, TG Baer, DS Ricci, KN O'Keefe, A Podolske, JR AF Provencal, R Gupta, M Owano, TG Baer, DS Ricci, KN O'Keefe, A Podolske, JR TI Cavity-enhanced quantum-cascade laser-based instrument for carbon monoxide measurements SO APPLIED OPTICS LA English DT Article ID TUNABLE DIODE-LASER; TEMPERATURE-MEASUREMENTS; ABSORPTION-SPECTROSCOPY; TRACE-GAS; CO; SPECTROMETER; SENSOR; CH4; EMISSION; H2O AB An autonomous instrument based on off-axis integrated cavity output spectroscopy has been developed and successfully deployed for measurements of carbon monoxide in the troposphere and tropopause onboard a NASA DC-8 aircraft. The instrument (Carbon Monoxide Gas Analyzer) consists of a measurement cell comprised of two high-reflectivity mirrors, a continuous-wave quantum-cascade laser, gas sampling system, control and data-acquisition electronics, and data-analysis software. CO measurements were determined from high-resolution CO absorption line shapes obtained by tuning the laser wavelength over the R(7)transition of the fundamental vibration band near 2172.8 cm(-1). The instrument reports CO mixing ratio (mole fraction) at a 1-Hz rate based on measured absorption, gas temperature, and pressure using Beer's Law. During several flights in May-June 2004 and January 2005 that reached altitudes of 41,000 ft (12.5 km), the instrument recorded CO values with a precision of 0.2 ppbv (1-s averaging time) and an accuracy limited by the reference CO gas cylinder (uncertainty <1.0%). Despite moderate turbulence and measurements of particulate-laden airflows, the instrument operated consistently and did not require any maintenance, mirror cleaning, or optical realignment during the flights. (c) 2005 Optical Society of America. C1 Los Gatos Res, Mountain View, CA USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Provencal, R (reprint author), Los Gatos Res, 67 E Evelyn Ave,Suite 3, Mountain View, CA USA. EM d.baer@lgrinc.com NR 34 TC 38 Z9 39 U1 1 U2 13 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 NOV 1 PY 2005 VL 44 IS 31 BP 6712 EP 6717 DI 10.1364/AO.44.006712 PG 6 WC Optics SC Optics GA 979JK UT WOS:000232938000021 PM 16270560 ER PT J AU Way, MJ Quintana, H Infante, L Lambas, DG Muriel, H AF Way, MJ Quintana, H Infante, L Lambas, DG Muriel, H TI Redshifts in the Southern Abell Redshift Survey clusters. I. The data SO ASTRONOMICAL JOURNAL LA English DT Article DE galaxies : clusters : general; galaxies : distances and redshifts ID APM GALAXY SURVEY; DIGITAL SKY SURVEY; RICH CLUSTERS; SUBSTRUCTURE; CATALOG; SPECTRA AB The Southern Abell Redshift Survey (SARS) contains 39 clusters of galaxies with redshifts in the range 0.0 < z < 0.31 and a median redshift depth of (z) over bar = 0.0845. SARS covers the region 0 degrees < delta < - 65 degrees, alpha < 5(h), alpha > 21(h) ( while avoiding the LMC and SMC), with \b\ > 40 degrees. Cluster locations were chosen from the Abell and Abell-Corwin-Olowin catalogs, while galaxy positions were selected from the Automatic Plate Measuring Facility galaxy catalog with extinction-corrected magnitudes in the range 15 <= b(J) < 19. SARS used the Las Campanas 2.5 m du Pont telescope, observing either 65 or 128 objects concurrently over a 1.5 deg(2) field. New redshifts for 3440 galaxies are reported in the fields of these 39 clusters of galaxies. C1 NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. Pontificia Univ Catolica Chile, Dept Astron & Astrophys, Santiago 22, Chile. Astron Observ, Grp Invest Astron Teor & Expt, RA-5000 Cordoba, Argentina. Consejo Nacl Invest Cient & Tecn, RA-1033 Buenos Aires, DF, Argentina. RP Way, MJ (reprint author), NASA, Ames Res Ctr, Div Space Sci, MS 245-6, Moffett Field, CA 94035 USA. RI Way, Michael/D-5254-2012; OI Way, Michael/0000-0003-3728-0475 NR 34 TC 12 Z9 12 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD NOV PY 2005 VL 130 IS 5 BP 2012 EP 2018 DI 10.1086/462418 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 979XI UT WOS:000232977900005 ER PT J AU Howell, JH AF Howell, JH TI Star formation histories of nearby elliptical galaxies. I. Volume-limited sample SO ASTRONOMICAL JOURNAL LA English DT Article DE galaxies : abundances; galaxies : elliptical and lenticular, cD; galaxies : evolution; galaxies : formation; galaxies : general; galaxies : stellar content ID STELLAR POPULATION-MODELS; DYNAMICALLY HOT GALAXIES; GLOBULAR-CLUSTER SYSTEMS; LOW-DENSITY ENVIRONMENTS; LINE-STRENGTH INDEXES; VLT SPECTROSCOPY; LICK INDEXES; S0 GALAXIES; EVOLUTION; NGC-4365 AB This work presents high signal-to-noise ratio spectroscopic observations of a representative sample of nearby elliptical galaxies. These observations provide a strong test of models for the formation of elliptical galaxies and their star formation histories. Combining these data with the Gonzalez data set, a volume-limited sample of 45 galaxies has been defined. Results are in agreement with previous studies: the existence of the metallicity hyperplane and the Z-plane of Trager and coworkers is confirmed, and the distribution is clearly due to physical variations in stellar population parameters and not measurement uncertainty. Trends between stellar population parameters and galaxy structural parameters suggest that angular momentum may determine the chemical abundance of a galaxy at a given mass. C1 Univ Calif Santa Cruz, Univ Calif Observ, Lick Observ, Dept Astron & Astrophys, Santa Cruz, CA 95064 USA. RP Howell, JH (reprint author), CALTECH, Jet Propuls Lab, Ctr Infrared Proc & Anal, Mail Stop 100-22, Pasadena, CA 91125 USA. EM jhhowell@ucolick.org NR 53 TC 27 Z9 27 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD NOV PY 2005 VL 130 IS 5 BP 2065 EP 2086 DI 10.1086/496974 PG 22 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 979XI UT WOS:000232977900009 ER PT J AU Nielsen, KE Wahlgren, GM Proffitt, CR Leckrone, DS Adelman, SJ AF Nielsen, KE Wahlgren, GM Proffitt, CR Leckrone, DS Adelman, SJ TI On the Ga II and Ga III resonance lines and the implication for chemical stratification in HGMN stars SO ASTRONOMICAL JOURNAL LA English DT Article DE line : profiles; stars : abundances; stars : chemically peculiar; ultraviolet : stars ID ADDED IUE SPECTRA; ELEMENTAL ABUNDANCE ANALYSES; NORMAL LATE-B; CHI-LUPI; PECULIAR STARS; GALLIUM; MERCURY; SPECTROGRAMS; ATMOSPHERES; IV AB The gallium abundance in HgMn stars has been reported to be different for analyses conducted from spectral lines in the optical versus those from the ultraviolet. We pursue this ultraviolet-optical discrepancy from a line-blending perspective by investigating the Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph (STIS) spectrum of the sharp-lined HgMn binary star chi Lup. Its gallium abundance is derived to be log N-Ga = 4.5 (log N-H = 12) based on nonresonance Ga II lines, and we are able to demonstrate the line-blending problems associated with the abundances determined from the resonance lines of Ga II lambda 1414 and Ga III lambda 1495. The HST STIS spectrum for chi Lup is also compared with a co-added International Ultraviolet Explorer (IUE) spectrum to further illustrate the importance of accounting for the line blending in quantitative abundance analyses. We have compared an IUE co-added spectrum of mu Lep with an LTE-based synthetic spectrum and managed to fit both Ga II lambda 1414 and Ga III lambda 1495 with an abundance of log N-Ga = 7.3. However, the fitting of these lines requires a dramatic change in the radiative damping constants, which may indicate a breakdown in our LTE modeling or the need to include other atmospheric effects. C1 Catholic Univ Amer, Dept Phys, Washington, DC 20064 USA. NASA, Explorat Universe Div, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Lund Univ, Lund Observ, SE-22100 Lund, Sweden. Comp Sci Corp, Sci Programs, Baltimore, MD 21218 USA. NASA, Hubble Space Telescope Project, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. The Citadel, Dept Phys, Charleston, SC 29409 USA. RP Nielsen, KE (reprint author), Catholic Univ Amer, Dept Phys, Washington, DC 20064 USA. EM nielsen@stis.gsfc.nasa.gov; glenn.wahlgren@astro.lu.se; proffitt@stsci.edu; dave.r.leckrone@nasa.gov; adelmans@citadel.edu NR 30 TC 8 Z9 8 U1 1 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD NOV PY 2005 VL 130 IS 5 BP 2312 EP 2317 DI 10.1086/491703 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 979XI UT WOS:000232977900030 ER PT J AU Gehrz, RD Hanner, MS Homich, AA Tokunaga, AT AF Gehrz, RD Hanner, MS Homich, AA Tokunaga, AT TI The infrared activity of comet P/Halley 1986 III at heliocentric distances from 0.6 to 5.92 AU SO ASTRONOMICAL JOURNAL LA English DT Article DE comets : individual (P/Halley 1986 III); dust, extinction; infrared : solar system ID BOPP C/1995 O1; HALLEY MONITORING PROGRAM; SMALL DUST GRAINS; HALE-BOPP; AIRBORNE SPECTROPHOTOMETRY; INNER COMA; P/HALLEY; POSTPERIHELION; SPECTROSCOPY; PERIHELION AB We present an analysis of the combined infrared data for comet 1P/Halley 1986 III acquired by Gehrz and Ney, Hanner and coworkers, Tokunaga and coworkers, Green and coworkers, Ryan and Campins, and Bregman and coworkers. This database, the largest single body of infrared photometric data for any comet, spans a wavelength range from 0.7 to 23 mu m and describes the activity of P/Halley at heliocentric distances from 0.6 to 5.92 AU. Coverage of the thermal infrared spectrum was obtained for heliocentric distances from 0.6 to 2.8 AU. The quantitative corrections and calibration procedures required to intercompare the individual data sets are described. Long-term trends in the heliocentric dependence of P/Halley's grain color temperature, silicate emission optical strength, average grain albedo, apparent luminosity, and infrared monochromatic fluxes are discussed. The normalized thermal infrared flux varied as r(-2.2) preperihelion and r(-2.1) postperihelion in accord with the slope of the water production rate, indicating a general correlation between dust and gas production. Large-amplitude short-term ( hours) fluctuations in all the observable quantities were seen in small apertures; these changes correlated with gas production rates and the presence of jets. Changes in JHK colors and the incomplete correlation between superheat and silicate feature strength imply variability in the grain composition, as well as in the size distribution. Based on a comparison of infrared data, comet Hale-Bopp (C/1995 O1) ejected a much higher relative abundance of submicron grains than Halley, and this pattern persisted to larger heliocentric distances. C1 Univ Minnesota, Dept Astron, Minneapolis, MN 55455 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Hawaii Manoa, Inst Astron, Honolulu, HI 96822 USA. RP Gehrz, RD (reprint author), Univ Minnesota, Dept Astron, 116 Church St SE, Minneapolis, MN 55455 USA. EM gehrz@astro.umn.edu; mhanner@astro.umass.edu; homich@lycos.com; tokunaga@ifa.hawaii.edu NR 41 TC 5 Z9 5 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD NOV PY 2005 VL 130 IS 5 BP 2383 EP 2391 DI 10.1086/496950 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 979XI UT WOS:000232977900036 ER PT J AU Bonamente, M Lieu, R Kaastra, J AF Bonamente, M Lieu, R Kaastra, J TI ROSAT observations of the soft X-ray background and of the cluster soft excess emission in the Hercules supercluster SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE galaxies : clusters : individual : MKW03s, A2052, A2063; X-rays : galaxies : clusters ID HOT INTERGALACTIC MEDIUM; ULTRAVIOLET-SPECTROSCOPIC-EXPLORER; OVI ABSORPTION; COMA CLUSTER; PG 0953+415; H I; GALAXIES; DIFFUSE; CONSTRAINTS; TEMPERATURE AB Recent observations with the XMM-Newton satellite confirmed the existence of the soft excess phenomenon in galaxy clusters, earlier discovered in several EUVE, ROSAT and BeppoSAX observations. Among the clusters for which XMM has reported detection of soft excess emission are MKW03s and A2052, two clusters in the Hercules concentration. The Hercules supercluster lies along the southern extension of the North Polar Spur, a region of bright soft X-ray emission clearly visible in ROSAT All-Sky Survey images. We analyze 11 pointed ROSAT PSPC observations toward 3 clusters in the Hercules concentration, MKW03s, A2052 and A2063, and 8 neighboring fields in order to investigate the soft X-ray emission in that region of the sky. We find that the soft X-ray emission varies by a factor of few on scales of few degrees, rendering the background subtraction a complex task. If the North Polar Spur emission is of local origin, we find that only A2052 and A2063 have evidence of cluster soft excess emission, and that the OVII emission lines detected in XMM observations of A2052 and MKW03s are not associated with the cluster. If part or all of the North Polar Spur soft X-ray enhancement is of extragalactic nature, the three clusters feature strong soft excess emission, and the OVII emission lines observed by XMM are genuinely associated with the clusters. We interpret the soft excess emission with the presence of warm gas, either intermixed with the hot intra-cluster medium or in filamentary structures located around the clusters, and estimate that the warm gas is approximately as massive as the hot intra-cluster medium. C1 NASA, Natl Space Sci Technol Ctr, Huntsville, AL 35812 USA. Univ Alabama, Dept Phys, Huntsville, AL 35899 USA. SRON, Utrecht, Netherlands. RP Bonamente, M (reprint author), NASA, Natl Space Sci Technol Ctr, Huntsville, AL 35812 USA. EM bonamem@uah.edu; lieur@cspar.uah.edu; J.S.Kaastra@sron.nl NR 44 TC 6 Z9 6 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 NOV PY 2005 VL 443 IS 1 BP 29 EP 39 DI 10.1051/0004-6361:20053169 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 976JP UT WOS:000232730000007 ER PT J AU De Groof, A Bastiaensen, C Muller, DAN Berghmans, D Poedts, S AF De Groof, A Bastiaensen, C Muller, DAN Berghmans, D Poedts, S TI Detailed comparison of downflows seen both in EIT 30.4 nm and Big Bear H alpha movies SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE Sun : atmosphere; Sun : activity ID SOLAR CORONAL LOOPS; LONGITUDINAL INTENSITY OSCILLATIONS; COOL FLARE LOOPS; MEASURED PARAMETERS; TRANSITION-REGION; DYNAMICS; PROMINENCES; TRACE; WAVES AB An EIT shutterless campaign was conducted on 11 July 2001 and provided 120 high-cadence (68 s) 30.4 nm images of the north-eastern quarter of the Sun. Systematic intensity variations are seen which appear to propagate along an off-disk loop-like structure. In this paper we study the nature of these intensity variations by confronting the EIT observations studied in De Groof et al. (2004, A&A, 415, 1141) with simultaneous H alpha images from Big Bear Solar Observatory. With the goal to carefully co-register the two image sets, we introduce a technique designed to compare data of two different instruments. The image series are first co-aligned and later overplotted in order to visualize and compare the behaviour of the propagating disturbances in both data sets. Since the same intensity variations are seen in the EIT 30.4 nm and in the Ha images, we confirm the interpretation of De Groof et al. (2004, A&A, 415, 1141) that we are observing downflows of relatively cool plasma. The origin of the downflows is explained by numerical simulations of "catastrophic cooling" in a coronal loop which is heated predominantly at its footpoints. C1 Katholieke Univ Leuven, Ctr Plasma Astrophys, B-3001 Louvain, Belgium. Univ Oslo, Inst Theoret Astrophys, N-0315 Oslo, Norway. Univ Oslo, Ctr Math Applicat, N-0316 Oslo, Norway. NASA, Goddard Space Flight Ctr, European Space Agcy, Res & Sci Support Dept, Greenbelt, MD 20771 USA. Royal Observ Belgium, B-1180 Brussels, Belgium. RP De Groof, A (reprint author), Katholieke Univ Leuven, Ctr Plasma Astrophys, Celestijnenlaan 200B, B-3001 Louvain, Belgium. EM Anik.DeGroff@wis.kuleuven.be; Daniel.Mueller@astro.uio.no; david.berghmans@oma.be; Stefaan.Poedts@wis.kuleuven.be RI Poedts, Stefaan/C-9775-2012 OI Poedts, Stefaan/0000-0002-1743-0651 NR 26 TC 27 Z9 27 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 NOV PY 2005 VL 443 IS 1 BP 319 EP 328 DI 10.1051/0004-6361:20053129 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 976JP UT WOS:000232730000033 ER PT J AU Paizis, A Ebisawa, K Tikkanen, T Rodriguez, J Chenevez, J Kuulkers, E Vilhu, O Courvoisier, TJL AF Paizis, A Ebisawa, K Tikkanen, T Rodriguez, J Chenevez, J Kuulkers, E Vilhu, O Courvoisier, TJL TI Resolving the hard X-ray emission of GX 5-1 with INTEGRAL SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE X-rays : binaries; binaries ( including multiple): close; stars : neutron; stars : individual : GX 5-1 ID GX 5-1; NEUTRON-STARS; CYGNUS X-2; JEM-X; BINARIES; ACCRETION; BEHAVIOR; COMPTONIZATION; EVOLUTION; SPECTRUM AB We present the study of one year of INTEGRAL data on the neutron star low mass X-ray binary GX 5-1. Thanks to the excellent angular resolution and sensitivity of INTEGRAL, we are able to obtain a high quality spectrum of GX 5-1 from similar to 5keV to similar to 100 keV, for the first time without contamination from the nearby black hole candidate GRS 1758-258 above 20 keV. During our observations, GX 5-1 was mostly found in the horizontal and normal branch of its hardness intensity diagram. A clear hard X-ray emission is observed above similar to 30 keV which exceeds the exponential cut-off spectrum expected from lower energies. This spectral flattening may have the same origin of the hard components observed in other Z sources as it shares the property of being characteristic to the horizontal branch. The hard excess is explained by introducing Compton up-scattering of soft photons from the neutron star surface due to a thin hot plasma expected in the boundary layer. The spectral changes of GX 5-1 downward along the "Z" pattern in the hardness intensity diagram can be well described in terms of monotonical decrease of the neutron star surface temperature. This may be a consequence of the gradual expansion of the boundary layer as the mass accretion rate increases. C1 INTEGRAL Sci Data Ctr, CH-1290 Chavannes Des Bois, Switzerland. Sez Milano, IASF, INAF, I-20133 Milan, Italy. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Helsinki Univ Observ, FIN-00014 Helsinki, Finland. CE Saclay, CNRS, FRE 2591, DSM,DAPNIA,SAp, F-91191 Gif Sur Yvette, France. Danish Space Res Inst, DK-2100 Copenhagen, Denmark. European Space Agcy, Estec, Res & Sci Support Dept, NL-2200 AG Noordwijk, Netherlands. Observ Geneva, CH-1290 Sauverny, Switzerland. RP Paizis, A (reprint author), INTEGRAL Sci Data Ctr, Chemin Ecogia 16, CH-1290 Chavannes Des Bois, Switzerland. EM Ada.Paizis@obs.unige.ch RI Chenevez, Jerome/F-5380-2010; OI Rodriguez, Jerome/0000-0002-4151-4468; Paizis, Adamantia/0000-0001-5067-0377 NR 48 TC 12 Z9 12 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 NOV PY 2005 VL 443 IS 2 BP 599 EP 608 DI 10.1051/0004-6361:20041647 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 982RM UT WOS:000233179300021 ER PT J AU Tagliaferri, G Antonelli, LA Chincarini, G Fernandez-Soto, A Malesani, D Della Valle, M D'Avanzo, P Grazian, A Testa, V Campana, S Covino, S Fiore, F Stella, L Castro-Tirado, AJ Gorosabel, J Burrows, DN Capalbi, M Cusumano, G Conciatore, ML D'Elia, V Filliatre, P Fugazza, D Gehrels, N Guetta, D Guziy, S Held, EV Hurley, K Israel, GL Jelinek, M Lazzati, D Lopez-Echarri, A Melandri, A Mirabel, IF Moles, M Moretti, A Mason, KO Nousek, J Osborne, J Pellizza, LJ Perna, R Piranomonte, S Piro, L Postigo, AD Romano, P AF Tagliaferri, G Antonelli, LA Chincarini, G Fernandez-Soto, A Malesani, D Della Valle, M D'Avanzo, P Grazian, A Testa, V Campana, S Covino, S Fiore, F Stella, L Castro-Tirado, AJ Gorosabel, J Burrows, DN Capalbi, M Cusumano, G Conciatore, ML D'Elia, V Filliatre, P Fugazza, D Gehrels, N Guetta, D Guziy, S Held, EV Hurley, K Israel, GL Jelinek, M Lazzati, D Lopez-Echarri, A Melandri, A Mirabel, IF Moles, M Moretti, A Mason, KO Nousek, J Osborne, J Pellizza, LJ Perna, R Piranomonte, S Piro, L Postigo, AD Romano, P TI GRB050904 at redshift 6.3: observations of the oldest cosmic explosion after the Big Bang SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE cosmology : observations; early Universe; gamma rays : bursts; gamma rays : individual : GRB 050904 ID GAMMA-RAY BURST; PHOTOMETRIC REDSHIFTS; SUPERNOVA; GALAXIES; UNIVERSE; SPECTRA; REIONIZATION; METALLICITY; PARAMETERS; DENSITY AB We present optical and near-infrared observations of the afterglow of the gamma-ray burst GRB050904. We derive a photometric redshift z = 6.3, estimated from the presence of the Lyman break falling between the I and J filters. This is by far the most distant GRB known to date. Its isotropic-equivalent energy is 3.4 x 10(53) erg in the rest- frame 110 110- 1100 keV energy band. Despite the high redshift, both the prompt and the afterglow emission are not peculiar with respect to other GRBs. We find a break in the J-band light curve at - t(b) = 2.6 +/- 1.0 d ( observer frame). If we assume this is the jet break, we derive a beaming-corrected energy E-gamma similar to (4 divided by 12) x 10(51) erg. This limit shows that GRB050904 is consistent with the Amati and Ghirlanda relations. This detection is consistent with the expected number of GRBs at z > 6 and shows that GRBs are a powerful tool to study the star formation history up to very high redshift. C1 INAF, Osservatorio Astron Brera, I-23807 Merate, Lc, Italy. INAF, Osservatorio Astron Roma, I-00040 Rome, Italy. Univ Milano Bicocca, Dipartimento Fis, I-20126 Milan, Italy. Univ Valencia, Astron Observ, Valencia 46071, Spain. ISAS, SISSA, I-34014 Trieste, Italy. INAF, Osservatorio Astrofis Arcetri, I-50125 Florence, Italy. Univ Insubria, Dipartimento Matemat & Fis, I-22100 Como, Italy. CSIC, Inst Astrofis Andalucia, E-18080 Granada, Spain. Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. ASI Sci Data Ctr, I-00044 Frascati, Roma, Italy. INAF, IASF, Sez Palermo, I-90146 Palermo, Italy. Lab Astroparticule & Cosmol, UMR 7164, F-75231 Paris, France. CEA Saclay, DAPNIA, DSM, Serv Astrophys, F-91911 Gif Sur Yvette, France. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. INAF, Osservatorio Astron Padova, I-35122 Padua, Italy. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Univ Colorado, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. Inst Astrofis Canarias, Tenerife 38200, Spain. Univ Cagliari, Dipartimento Fis, I-09042 Monserrato, Ca, Italy. European So Observ Vitacura, Santiago 19, Chile. UCL, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England. Univ Leicester, Dept Phys & Astron, Xray & Observat Astron Grp, Leicester LE1 7RH, Leics, England. Univ Paris 07, CEA Saclay, Serv Astrophys, AIM,CNRS,UMR 7158, F-91191 Gif Sur Yvette, France. INAF, IASF, Sez Roma, I-00133 Rome, Italy. RP INAF, Osservatorio Astron Brera, Via E Bianchi 46, I-23807 Merate, Lc, Italy. EM tagliaferri@merate.mi.astro.it RI Fernandez-Soto, Alberto/A-2443-2009; Gehrels, Neil/D-2971-2012; PIRO, LUIGI/E-4954-2013; Jelinek, Martin/E-5290-2016; OI Fernandez-Soto, Alberto/0000-0002-5732-3121; PIRO, LUIGI/0000-0003-4159-3984; Jelinek, Martin/0000-0003-3922-7416; D'Elia, Valerio/0000-0002-7320-5862; guetta, dafne/0000-0002-7349-1109; Held, Enrico Valerio/0000-0002-4609-3463; Cusumano, Giancarlo/0000-0002-8151-1990; moretti, alberto/0000-0002-9770-0315; Castro-Tirado, A. J./0000-0003-2999-3563; Della Valle, Massimo/0000-0003-3142-5020; Israel, GianLuca/0000-0001-5480-6438; de Ugarte Postigo, Antonio/0000-0001-7717-5085; Covino, Stefano/0000-0001-9078-5507; Tagliaferri, Gianpiero/0000-0003-0121-0723; Testa, Vincenzo/0000-0003-1033-1340; Fiore, Fabrizio/0000-0002-4031-4157 NR 54 TC 104 Z9 104 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 NOV PY 2005 VL 443 IS 1 BP L1 EP L5 DI 10.1051/0004-6361:200500196 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 976JP UT WOS:000232730000001 ER PT J AU Kimura, Y Kurumada, M Tamura, K Koike, C Chihara, H Kaito, C AF Kimura, Y Kurumada, M Tamura, K Koike, C Chihara, H Kaito, C TI Laboratory production of magnesium sulfide grains and their characteristic infrared spectra due to shape SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE methods : laboratory; stars : AGB and post-AGB; infrared : ISM; infrared : stars ID CARBON-RICH STARS; EMISSION FEATURE; PARTICLES AB Nanosized MgS grains, which have been considered the origin of the 30 mu m emission feature of carbon-rich evolved objects, were produced from the gas phase using an advanced gas evaporation method. The far-infrared spectrum of cubic MgS grains showed a characteristic absorption peak at 311 cm(-1) (32.1 mu m) with three shoulders at 460, 400 and 262 cm(-1) (21.7, 25.0 and 38.2 mu m). On the other hand, when the grains were roundish or network-like, the absorption peak at 250 cm(-1) became predominant. The cubic MgS grains were produced by direct nucleation from the gas phase. In the case of production via a gas-solid reaction, the MgS grains were network-like. Therefore, the formation environments of MgS grains around carbon-rich evolved objects may be predicted from the intensity of 310 and 250 cm(-1) bands. We suggest that the origins of the absorption band at 310 and 250 cm(-1) are (100), (110) and/or (111) surfaces of MgS grains, respectively. C1 Ritsumeikan Univ, Dept Phys, Shiga 5258577, Japan. Kyoto Pharmaceut Univ, Phys Lab, Kyoto 6078414, Japan. Osaka Univ, Dept Earth & Space Sci, Osaka 5600043, Japan. RP Kimura, Y (reprint author), NASAfs, Goddard Space Flight Ctr, Astrochem Lab, Solar Syst Explorat Div, Code 691, Greenbelt, MD 20771 USA. EM rp092955@se.ritsumei.ac.jp RI Kimura, Yuki/J-9635-2014 OI Kimura, Yuki/0000-0002-9218-7663 NR 18 TC 9 Z9 9 U1 1 U2 3 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 NOV PY 2005 VL 442 IS 2 BP 507 EP 512 DI 10.1051/0004-6361:20052757 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 971SH UT WOS:000232404400017 ER PT J AU Jimenez-Bailon, E Santos-Lleo, M Dahlem, M Ehle, M Mas-Hesse, JM Guainazzi, M Heckman, TM Weaver, KA AF Jimenez-Bailon, E Santos-Lleo, M Dahlem, M Ehle, M Mas-Hesse, JM Guainazzi, M Heckman, TM Weaver, KA TI X-ray emission from NGC 1808: more than a complex starburst SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE galaxies : active; galaxies : nuclei; galaxies : general; X-rays : general; galaxies : evolution; galaxies : halos; galaxies : starburst; individual : NGC 1808 ID REFLECTION GRATING SPECTROMETER; GALACTIC NUCLEUS NGC-4303; SPIRAL GALAXY NGC-1808; 2-10 KEV LUMINOSITY; STAR-FORMATION RATE; XMM-NEWTON; LINE OBSERVATIONS; SEYFERT-GALAXIES; RADIO-CONTINUUM; NEARBY GALAXIES AB Earlier observations of NGC1808 in various wavebands (X-ray, optical, near-infrared, radio) provided evidence for the existence of either a starburst or a Seyfert 2 nucleus. We here present the results of multiwavelength XMM-Newton and Chandra observations, which directly prove the co-existence of thermal diffuse plasma and non-nuclear unresolved point-like sources associated with the starburst activity, along with a Low Luminosity Active Galactic Nucleus (LLAGN) or an Ultra Luminous X-ray source (ULX). The broad bandwidth of XMM-Newton allows us to show that the unresolved nuclear source in NGC 1808 dominates the hard X-ray spectrum, while the emission in the soft regime, below 1 keV, is dominated by a thermal component associated to an extended starburst. Both EPIC and RGS data provide reliable detections of a number of emission lines from heavy elements, with abundances ranging from roughly 0.7 to 2.2 Z(.) for different elements. However, no 6.4 keV Fe K alpha fluorescence line emission was detected. The analysis of the nuclear region of NGC1808 allows us to detect and disentangle the contribution of an unresolved nuclear X-ray source and the starburst region, but the exact nature of the nucleus remains unknown. The observed luminosity of NGC 1808 is L2-10 keV = (1.61 +/- 0.06) x 10(40) erg s(-1). A comparison of our OM 212 nm image with a CTIO 4-m telescope H alpha frame shows a good general correspondence between the emission from massive stars and warm ionized gas, with minor deviations near the ends of the bar in NGC 1808. An aditional, very soft thermal spectral component with kT similar or equal to 0.1 keV has been discovered in the XMM-Newton spectral analysis, which most likely originates from the halo of NGC 1808. C1 ESA, XMM Newton Sci Operat Ctr, ESAC, Madrid 28080, Spain. Paul Wild Observ, ATNF, CSIRO, Narrabri, NSW 2390, Australia. CSIC, INTA, Ctr Astrobiol, Madrid 28850, Spain. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. RP Jimenez-Bailon, E (reprint author), ESA, XMM Newton Sci Operat Ctr, ESAC, Apartado 50727, Madrid 28080, Spain. EM Jimenez@sciops.esa.int RI Mas-Hesse, J. Miguel /K-6805-2014 OI Mas-Hesse, J. Miguel /0000-0002-8823-9723 NR 54 TC 23 Z9 23 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 NOV PY 2005 VL 442 IS 3 BP 861 EP 877 DI 10.1051/0004-6361:20053022 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 974AC UT WOS:000232562700016 ER PT J AU Guenther, EW Paulson, DB Cochran, WD Patience, J Hatzes, AP Macintosh, B AF Guenther, EW Paulson, DB Cochran, WD Patience, J Hatzes, AP Macintosh, B TI Low-mass companions to Hyades stars SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE stars : low-mass, brown dwarfs; stars : binaries : spectroscopic; stars : binaries : visual; stars : planetary systems ID BROWN DWARF COMPANION; CANDIDATE SUBSTELLAR COMPANION; PRE-MAIN-SEQUENCE; SOLAR-TYPE STARS; LUMINOSITY-RELATION; ADAPTIVE OPTICS; SPECTROSCOPIC SURVEY; EXTRASOLAR PLANETS; MAGNETIC ACTIVITY; PROPER MOTION AB It is now well established that a large fraction of the low-mass stars are binaries or higher order multiples. Similarly a sizable fraction have giant planets. In contrast to these, the situation for brown dwarf companions is complicated: While close systems seem to be extremely rare, wide systems are possibly more common. In this paper, we present new results on a survey for low-mass companions in the Hyades. After measuring precisely the radial velocity of 98 Hyades dwarf stars for 5 years, we have selected all stars that show low-amplitude long-period trends. With AO-observations of these 14 stars we found companion candidates around nine of them, where one star has two companions. The two companions of HIP 16548 have masses between 0.07 to 0.08 M-., and are thus either brown dwarfs or very low mass stars. In the case of HAN 172 we found a companion with a mass between 0.08 to 0.10 M-., which is again between a star and a brown dwarf. The other seven stars all have stellar companions. In two additional cases, the RV-variations are presumably caused by stellar activity, and in another case the companion could be a short-period binary. The images of the remaining two stars are slightly elongated, which might imply that even these are binaries. Because at least 12 of the 14 stars showing low-amplitude RV trends turn out to have companions with a mass >= 70 M-Jupiter, or are just active, we finally estimate the number of companions with masses between 10 M-Jupiter and 70 M-Jupiter within 8 AU of the host stars in the Hyades as <= 2%. C1 Thuringer Landessternwarte Tautenburg, D-07778 Tautenburg, Germany. NASA, Goddard Space Flight Ctr, Planetary Syst Branch, Greenbelt, MD 20771 USA. Univ Texas, McDonald Observ, Austin, TX 78712 USA. CALTECH, Div Phys Math & Astron, Pasadena, CA 91125 USA. Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94551 USA. RP Guenther, EW (reprint author), Thuringer Landessternwarte Tautenburg, Sternwarte 5, D-07778 Tautenburg, Germany. EM guenther@tls-tautenburg.de NR 60 TC 15 Z9 15 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 NOV PY 2005 VL 442 IS 3 BP 1031 EP 1039 DI 10.1051/0004-6361:20052851 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 974AC UT WOS:000232562700030 ER PT J AU Perri, M Giommi, P Capalbi, M Amati, L Frontera, F Chincarini, G Campana, S Moretti, A Romano, P Tagliaferri, G Cusumano, G La Parola, V Mangano, V Mineo, T Burrows, DN Hill, JE Kennea, JA Morris, DC Pagani, C Nousek, JA Angelini, L Gehrels, N Still, M Beardmore, AP Goad, MR Godet, O O'Brien, PT Osborne, JP Page, KL AF Perri, M Giommi, P Capalbi, M Amati, L Frontera, F Chincarini, G Campana, S Moretti, A Romano, P Tagliaferri, G Cusumano, G La Parola, V Mangano, V Mineo, T Burrows, DN Hill, JE Kennea, JA Morris, DC Pagani, C Nousek, JA Angelini, L Gehrels, N Still, M Beardmore, AP Goad, MR Godet, O O'Brien, PT Osborne, JP Page, KL TI Swift XRT observations of the breaking X-ray afterglow of GRB 050318 SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE gamma rays : bursts; X-rays : individual : GRB 050318 ID BURSTS; EMISSION; BEPPOSAX; ENERGETICS; TELESCOPE; ENERGY AB We report the results of Swift X-Ray Telescope (XRT) observations of GRB 050318. This event triggered the Burst Alert Telescope ( BAT) aboard Swift and was followed-up with XRT and UVOT for 11 consecutive orbits starting from 54 min after the trigger. A previously unknown fading X-ray source was detected and accurately monitored. The source was found to decrease in intensity with time and a clear temporal break occurring at similar to 18 000 s after the trigger was observed. The X-ray light curve was found to be consistent with a broken power-law with decay indices -1.17 +/- 0.08 and -2.10(-0.24)(+0.22) before and after the break. The spectrum of the X-ray afterglow was well described by a photoelectrically absorbed power-law with energy index of -1.09 +/- 0.09. No evidence of spectral evolution was found. We compare these results with those obtained with UVOT and separately reported and refine the data analysis of BAT. We discuss our results in the framework of a collimated fireball model and a synchrotron radiation emission mechanism. C1 ASI Sci Data Ctr, I-00044 Frascati, Italy. Univ Rome, Unita Osservaz, Agenzia Spaziale Italiana, I-00198 Rome, Italy. Ist Astrofis Spaziale & Fis Cosm, INAF, Sez Bologna, I-40129 Bologna, Italy. Univ Ferrara, Dipartimento Fis, I-44100 Ferrara, Italy. Osserv Astron Brera, INAF, I-23807 Merate, Italy. Univ Milano Bicocca, Dipartimento Fis, I-20126 Milan, Italy. Ist Astrofis Spaziale & Fis Cosm, INAF, Sez Palermo, I-90146 Palermo, Italy. Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Space Res Assoc, Columbia, MD 21044 USA. Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. RP Perri, M (reprint author), ASI Sci Data Ctr, Via Galileo Galilei, I-00044 Frascati, Italy. EM perri@asdc.asi.it RI Gehrels, Neil/D-2971-2012; Amati, Lorenzo/N-5586-2015; OI Perri, Matteo/0000-0003-3613-4409; La Parola, Valentina/0000-0002-8087-6488; Amati, Lorenzo/0000-0001-5355-7388; Romano, Patrizia/0000-0003-0258-7469; Tagliaferri, Gianpiero/0000-0003-0121-0723; Campana, Sergio/0000-0001-6278-1576; giommi, paolo/0000-0002-2265-5003; Cusumano, Giancarlo/0000-0002-8151-1990; moretti, alberto/0000-0002-9770-0315; Mineo, Teresa/0000-0002-4931-8445 NR 38 TC 14 Z9 14 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 NOV PY 2005 VL 442 IS 2 BP L1 EP L5 DI 10.1051/0004-6361:200500173 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 971SH UT WOS:000232404400001 ER PT J AU Starling, RLC Vreeswijk, PM Ellison, SL Rol, E Wiersema, K Levan, AJ Tanvir, NR Wijers, RAMJ Tadhunter, C Zaurin, JR Delgado, RMG Kouveliotou, C AF Starling, RLC Vreeswijk, PM Ellison, SL Rol, E Wiersema, K Levan, AJ Tanvir, NR Wijers, RAMJ Tadhunter, C Zaurin, JR Delgado, RMG Kouveliotou, C TI Gas and dust properties in the afterglow spectra of GRB 050730 SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE gamma rays : bursts; galaxies : distances and redshifts; cosmology : observations ID LUMINOSITY-METALLICITY RELATION; STAR-FORMING GALAXIES; BURST HOST GALAXIES; HIGH COLUMN DENSITY; SUBMILLIMETER; SPECTROSCOPY; GRB-021004; EMISSION; FIELD; JET AB We present early WHT ISIS optical spectroscopy of the afterglow of gamma-ray burst GRB050730. The spectrum shows a DLA system with the highest measured hydrogen column to date: N(H I) = 22.1 +/- 0.1 at the third-highest GRB redshift z = 3.968. Our analysis of the Swift XRT X-ray observations of the early afterglow show X-ray flares accompanied by decreasing X-ray absorption. From both the optical and the X-ray spectra we constrain the dust and gas properties of the host galaxy. We find the host to be a low metallicity galaxy, with low dust content. Much of the X-ray absorbing gas is situated close to the GRB, whilst the H I absorption causing the DLA is most likely located further out. C1 Univ Amsterdam, Astron Inst Anton Pannekoek, NL-1098 SJ Amsterdam, Netherlands. European So Observ, Santiago 19, Chile. Univ Victoria, Dept Phys & Astron, Victoria, BC V8P 1A1, Canada. Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. Univ Hertfordshire, Ctr Astrophys Res, Hatfield AL10 9AB, Herts, England. Univ Sheffield, Dept Phys & Astron, Sheffield S3 7RH, S Yorkshire, England. CSIC, Inst Astrofis Andalucia, E-18080 Granada, Spain. NASA, George C Marshall Space Flight Ctr, NSSTC, Huntsville, AL 35805 USA. RP Starling, RLC (reprint author), Univ Amsterdam, Astron Inst Anton Pannekoek, Kruislaan 403, NL-1098 SJ Amsterdam, Netherlands. EM starling@science.uva.nl OI Wijers, Ralph/0000-0002-3101-1808 NR 40 TC 60 Z9 60 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 NOV PY 2005 VL 442 IS 2 BP L21 EP U6 DI 10.1051/0004-6361:200500181 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 971SH UT WOS:000232404400005 ER PT J AU Conselice, CJ Vreeswijk, PM Fruchter, AS Levan, A Kouveliotou, C Fynbo, JPU Gorosabel, J Tanvir, NR Thorsett, SE AF Conselice, CJ Vreeswijk, PM Fruchter, AS Levan, A Kouveliotou, C Fynbo, JPU Gorosabel, J Tanvir, NR Thorsett, SE TI Gamma-ray burst-selected high-redshift galaxies: Comparison to field galaxy populations to z similar to 3 SO ASTROPHYSICAL JOURNAL LA English DT Article DE early universe; galaxies : ISM; gamma rays : observations; quasars : absorption lines ID HUBBLE-SPACE-TELESCOPE; HIGH COLUMN DENSITY; ORIGINS DEEP SURVEY; HOST GALAXY; STAR-FORMATION; STARBURST GALAXIES; OPTICAL COUNTERPART; PHYSICAL MORPHOLOGY; KECK SPECTROSCOPY; NEARBY GALAXIES AB We study the internal structural properties of 37 long-duration gamma-ray burst (GRB) host galaxies imaged with the Hubble Space Telescope (HST). Our goal is to gain insights in the types of galaxies that give rise to GRBs and the relationship of GRB hosts to high-redshift galaxies selected through more traditional photometric methods. We measure structural properties of our sample from HST observations obtained after the GRB afterglow faded. Fitting exponential disk (typical for spirals) and r(1/4) (typical for ellipticals) models to the surface brightness profiles of eight z < 1.2 bright host galaxies, we find that the disk model is slightly preferred for most hosts, although two galaxies are fit best with an r(1/4) profile. We furthermore measure the central concentrations and asymmetries of all 37 host galaxies using the CAS (concentration, asymmetry, clumpiness) system and compare with values for galaxies in the Hubble Deep Field and systems present on the GRB host images. Our first main conclusion is that GRB hosts exhibit a surprisingly broad diversity of galaxy types. A significant fraction (68%) of host galaxies are situated in a region of the concentration-asymmetry diagram occupied by spirals or peculiar/merging galaxies. Twelve hosts (32%) are situated in the region occupied by elliptical galaxies, having high concentration indices indicative of early types or early types in formation. These results show that GRB host galaxies are not a single morphological type but span the available range of galaxy types seen at high redshift. We also find some evidence for evolution in GRB host galaxy morphology, such that hosts at z > 1 have a relatively high light concentration, indicating that these systems are perhaps progenitors of massive galaxies, or are compact blue star-forming galaxies. We find that GRB hosts at z > 1 are different from the general field population at z > 1 in terms of light concentration, at > 99.5% confidence, yet have sizes similar to the general z > 1 population. This is the opposite of the effect at z < 1, where GRB hosts are smaller than average. We argue that GRB hosts trace the starburst population at high redshift, as similarly concentrated galaxies at z > 2 are undergoing a disproportionate amount of star formation for their luminosities. Furthermore, our results show that GRBs are not only an effective tracer of star formation but are perhaps ideal tracers of typical galaxies undergoing star formation at any epoch, making them perhaps our best hope of locating the earliest galaxies at z > 7. C1 CALTECH, Pasadena, CA 91125 USA. Univ Amsterdam, Astron Inst Anton Pannekoek, NL-1098 SJ Amsterdam, Netherlands. Ctr High Energy Astrophys, NL-1098 SJ Amsterdam, Netherlands. European So Observ, Santiago 19, Chile. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. NASA, George C Marshall Space Flight Ctr, Natl Space Sci Technol Ctr, Huntsville, AL 35805 USA. Univ Copenhagen, Niels Bohr Inst, DK-2100 Copenhagen, Denmark. CSIC, IAA, E-18008 Granada, Spain. Univ Hertfordshire, Ctr Astrophys, Hatfield AL10 9AB, Herts, England. Univ Calif Santa Cruz, Dept Astron & Astrophys, Santa Cruz, CA 95064 USA. RP CALTECH, Mail Code 105-24, Pasadena, CA 91125 USA. EM cc@astro.caltech.edu; fruchter@stsci.edu RI Conselice, Christopher/B-4348-2013; OI Thorsett, Stephen/0000-0002-2025-9613; Conselice, Christopher/0000-0003-1949-7638 NR 94 TC 60 Z9 62 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 NOV 1 PY 2005 VL 633 IS 1 BP 29 EP 40 DI 10.1086/432829 PN 1 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 977VV UT WOS:000232832500004 ER PT J AU Tang, SM Zhang, SN AF Tang, SM Zhang, SN TI Critical examinations of QSO redshift periodicities and associations with galaxies in Sloan Digital Sky Survey data SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; large-scale structure of universe; quasars : general ID QUASI-STELLAR OBJECTS; SPECTROSCOPIC TARGET SELECTION; 1ST DATA RELEASE; ACTIVE GALAXIES; CATALOG; DISTANCES; SAMPLE AB We have used the publicly available data from the Sloan Digital Sky Survey and 2dF QSO redshift survey to test the hypothesis that QSOs are ejected from active galaxies with periodic noncosmological redshifts. For two different intrinsic redshift models, namely the Karlsson log (1 + z) model and Bell's decreasing intrinsic redshift (DIR) model, we do two tests. First, using different criteria, we generate four sets of QSO-galaxy pairs and find there is no evidence for a periodicity at the predicted frequency in log (1 + z), or at any other frequency. We then check the relationship between high-redshift QSOs and nearby active galaxies, and we find that the distribution of projected distance between high-redshift QSOs and nearby active galaxies and the distribution of redshifts of those active galaxies are consistent with a distribution of simulated random pairs, completely different from Bell's previous conclusion. We also analyze the periodicity in redshifts of QSOs, and no periodicity is found in high-completeness samples, contrary to the DIR model. These results support the hypothesis that QSOs are not ejected from active galaxies. C1 Tsing Hua Univ, Dept Phys, Beijing 100084, Peoples R China. Tsing Hua Univ, Ctr Astrophys, Beijing 100084, Peoples R China. Univ Alabama, Dept Phys, Huntsville, AL 35899 USA. NASA, George C Marshall Space Flight Ctr, Space Sci Lab, Huntsville, AL 35812 USA. Chinese Acad Sci, Inst High Energy Phys, Beijing 100039, Peoples R China. RP Tang, SM (reprint author), Tsing Hua Univ, Dept Phys, Beijing 100084, Peoples R China. EM tangsm99@mails.tsinghua.edu.cn; zhangsn@tsinghua.edu.cn NR 21 TC 7 Z9 7 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 NOV 1 PY 2005 VL 633 IS 1 BP 41 EP 51 DI 10.1086/432754 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 977VV UT WOS:000232832500005 ER PT J AU Fynbo, JPU Gorosabel, J Smette, A Fruchter, A Hjorth, J Pedersen, K Levan, A Burud, I Sahu, K Vreeswijk, PM Bergeron, E Kouveliotou, C Tanvir, N Thorsett, SE Wijers, RAMJ Ceron, JMC Castro-Tirado, AC Garnavich, P Holland, ST Jakobsson, P Moller, P Nugent, P Pian, E Rhoads, J Thomsen, B Watson, D Woosley, S AF Fynbo, JPU Gorosabel, J Smette, A Fruchter, A Hjorth, J Pedersen, K Levan, A Burud, I Sahu, K Vreeswijk, PM Bergeron, E Kouveliotou, C Tanvir, N Thorsett, SE Wijers, RAMJ Ceron, JMC Castro-Tirado, AC Garnavich, P Holland, ST Jakobsson, P Moller, P Nugent, P Pian, E Rhoads, J Thomsen, B Watson, D Woosley, S TI On the afterglow and host galaxy of GRB 021004: A comprehensive study with the Hubble space telescope SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmology : observations; gamma rays : bursts ID GAMMA-RAY BURST; LYMAN-ALPHA EMISSION; HIGH COLUMN DENSITY; STAR-FORMATION; HIGH-REDSHIFT; OPTICAL AFTERGLOW; LOW METALLICITY; LIGHT CURVES; DUST; POLARIZATION AB We report on Hubble Space Telescope (HST) observations of the late-time afterglow and host galaxy of GRB 021004 (z = 2.33). Although this gamma- ray burst (GRB) is one of the best observed so far in terms of sampling in the time domain, multiwavelength coverage, and polarimetric observations, there is substantial disagreement between different interpretations of data sets on this burst in the literature. We have observed the field of GRB 021004 with the HST at multiple epochs from 3 days until almost 10 months after the burst. With the STIS PRISM and G430L spectroscopy, we cover the spectral region from about 2000 to 5700 angstrom, corresponding to 600-1700 angstrom in the rest frame. From the limit on the flux recovery blueward of the Lyman limit, we constrain the H I column density to be above 1 x 10(18) cm(-2) (5 sigma). On the basis of ACS and NICMOS imaging, we find that the afterglow evolved achromatically within the errors (any variation must be less than 5%) during the period of the HST observations. The color changes observed by other authors during the first 4 days must be related to a stochastic phenomenon superimposed on an afterglow component with a constant spectral shape. This achromaticity implies that the cooling break has remained on the blue side of the optical part of the spectrum for at least 2 weeks after the explosion. The optical-to-X-ray slope beta(OX) is consistent with being the same at 1.4 and 52.4 days after the burst. This indicates that the cooling frequency is constant and, hence, according to fireball models, that the circumburst medium has a constant density profile. The late-time slope of the light curve (alpha(2), F-v proportional to t(-alpha 2)) is in the range alpha(2) = 1.8-1.9 and is inconsistent with a single power law. This could be due to a late-time flattening caused by the transition to nonrelativistic expansion or could be due to excess emission (a "bump" in the light curve) about 7 days after the burst. The host galaxy is, like most previously studied GRB hosts, a (very) blue starburst galaxy with no evidence for dust and with strong Ly alpha emission. The star formation rate of the host is about 10 M-circle dot yr(-1) on the basis of both the strength of the UV continuum and the Ly alpha luminosity. The spectral energy distribution of the host implies an age in the range 30-100 Myr for the dominant stellar population. The afterglow was located very close (similar to 100 pc) to the center of the host, implying that the progenitor was possibly associated with a circumnuclear starburst. C1 Univ Copenhagen, Niels Bohr Inst, DK-2100 Copenhagen, Denmark. Space Telescope Sci Inst, Baltimore, MD 21218 USA. CSIC, IAA, E-11080 Granada, Spain. European So Observ, Santiago, Chile. Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. NASA, Marshall Space Flight Ctr, Natl Space Sci & Technol Ctr, Huntsville, AL 35805 USA. Univ Hertfordshire, Dept Phys Sci, Hatfield AL10 9AB, Herts, England. Univ Calif Santa Cruz, Dept Astron & Astrophys, Santa Cruz, CA 95064 USA. NSSTC, Univ Space Res Assoc, Huntsville, AL 35805 USA. Univ Amsterdam, Inst Astron, NL-1098 SJ Amsterdam, Netherlands. Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. European So Observ, D-85748 Munich, Germany. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Osserv Astron Trieste, I-34131 Trieste, Italy. Aarhus Univ, Dept Phys & Astron, DK-8000 Aarhus, Denmark. RP Univ Copenhagen, Niels Bohr Inst, Juliane Maries Vej 30, DK-2100 Copenhagen, Denmark. RI Hjorth, Jens/M-5787-2014; Watson, Darach/E-4521-2015; Jakobsson, Pall/L-9950-2015; OI Hjorth, Jens/0000-0002-4571-2306; Watson, Darach/0000-0002-4465-8264; Jakobsson, Pall/0000-0002-9404-5650; Thorsett, Stephen/0000-0002-2025-9613; Wijers, Ralph/0000-0002-3101-1808; Castro-Tirado, A. J./0000-0003-2999-3563; Pian, Elena/0000-0001-8646-4858 NR 75 TC 29 Z9 29 U1 0 U2 3 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 NOV 1 PY 2005 VL 633 IS 1 BP 317 EP 327 DI 10.1086/432633 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 977VV UT WOS:000232832500030 ER PT J AU Altamirano, D van der Klis, M Mendez, M Migliari, S Jonker, PG Tiengo, A Zhang, W AF Altamirano, D van der Klis, M Mendez, M Migliari, S Jonker, PG Tiengo, A Zhang, W TI The island state of the atoll source 4U 1820-30 SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; binaries : close; stars : individual (4U 0614+09, 4U 1608-52, 4U 1728-34, 4U 1820-30, SAX J1808.4-3658); stars : neutron; X-rays : stars ID X-RAY BINARIES; CLUSTER NGC 6624; 4U 1820-30; TIMING FEATURES; POWER SPECTRA; LOW-FREQUENCY; DISCOVERY; OSCILLATIONS; VARIABILITY; EXPLORER AB We study the rapid X-ray time variability in all public data available from the Rossi X-Ray Timing Explorer Proportional Counter Array on the atoll source 4U 1820-30 in the low-luminosity island state. A total of similar to 46 ks of data were used. We compare the frequencies of the variability components of 4U 1820-30 with those in other atoll sources. These frequencies were previously found to follow a universal scheme of correlations. We find that 4U 1820-30 shows correlations that are shifted by factors of 1.13 +/- 0: 01 and 1: 21 +/- 0: 02 with respect to those in other atoll sources. These shifts are similar to, but smaller than, the shift factor of similar to 1.45 previously reported for some accreting millisecond pulsars. Therefore, 4U 1820-30 is the first atoll source that shows no significant pulsations but has a significant shift in the frequency correlations compared with the other three nonpulsating atoll sources. C1 Univ Amsterdam, Astron Inst, NL-1098 SJ Amsterdam, Netherlands. Univ Amsterdam, Ctr High Energy Astrophys, NL-1098 SJ Amsterdam, Netherlands. SRON, Natl Inst Space Res, NL-3584 CA Utrecht, Netherlands. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. INAF, Ist Astrofis Spaziale & Fis Cosmica, Sez Milano G Occhialini, I-20133 Milan, Italy. Univ Milan, Dipartimento Fis, I-20133 Milan, Italy. NASA, Goddard Space Flight Ctr, Lab Xray Astrophys, Greenbelt, MD 20771 USA. RP Univ Amsterdam, Astron Inst, Kruislaan 403, NL-1098 SJ Amsterdam, Netherlands. EM diego@science.uva.nl RI Mendez, Mariano/C-8011-2012; OI Mendez, Mariano/0000-0003-2187-2708; Tiengo, Andrea/0000-0002-6038-1090 NR 38 TC 23 Z9 23 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 NOV 1 PY 2005 VL 633 IS 1 BP 358 EP 366 DI 10.1086/447761 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 977VV UT WOS:000232832500034 ER PT J AU Corbet, RHD Markwardt, CB Swank, JH AF Corbet, RHD Markwardt, CB Swank, JH TI Rossi X-ray timing explorer observations of the X-ray pulsar EXO 1722-363: A candidate eclipsing supergiant system SO ASTROPHYSICAL JOURNAL LA English DT Article DE stars : individual (EXO 1722-363); stars : neutron; X-rays : stars ID X1722-36 AB Observations made of the X-ray pulsar EXO 1722 - 363 using the Proportional Counter Array (PCA) and the All Sky Monitor (ASM) on board the Rossi X-Ray Timing Explorer (RXTE) reveal the orbital period of this system to be 9: 741 +/- 0: 004 days from periodic changes in the source flux. The detection of eclipses together with the values of the pulse and orbital periods suggests that this source consists of a neutron star accreting from the stellar wind of an early spectral type supergiant companion. Pulse timing measurements were also obtained but do not strongly constrain the system parameters. The X-ray spectra can be well fitted with a model consisting of a power law with a high-energy cutoff and, for some spectra, a blackbody component with a temperature of approximately 0.85 keV. C1 NASA, Goddard Space Flight Ctr, XRay Astrophys Lab, Greenbelt, MD 20771 USA. Univ Maryland, Dept Astron, College Pk, MD 20742 USA. RP NASA, Goddard Space Flight Ctr, XRay Astrophys Lab, Code 662, Greenbelt, MD 20771 USA. EM corbet@gsfc.nasa.gov RI Swank, Jean/F-2693-2012 NR 21 TC 10 Z9 10 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 NOV 1 PY 2005 VL 633 IS 1 BP 377 EP 383 DI 10.1086/444610 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 977VV UT WOS:000232832500036 ER PT J AU Robinson, RD Wheatley, JM Welsh, BY Forster, K Morrissey, P Seibert, M Rich, RM Salim, S Barlow, TA Bianchi, L Byun, YI Donas, J Friedman, PG Heckman, TM Jelinsky, PN Lee, YW Madore, BF Malina, RF Martin, DC Milliard, B Neff, SG Schiminovich, D Siegmund, OHW Small, T Szalay, AS Wyder, TK AF Robinson, RD Wheatley, JM Welsh, BY Forster, K Morrissey, P Seibert, M Rich, RM Salim, S Barlow, TA Bianchi, L Byun, YI Donas, J Friedman, PG Heckman, TM Jelinsky, PN Lee, YW Madore, BF Malina, RF Martin, DC Milliard, B Neff, SG Schiminovich, D Siegmund, OHW Small, T Szalay, AS Wyder, TK TI GALEX observations of an energetic ultraviolet flare on the dM4e star GJ 3685A SO ASTROPHYSICAL JOURNAL LA English DT Article DE stars : flare; stars : individual (GJ 3685A); stars : late-type; stars : variables : other; ultraviolet : stars ID YZ-CANIS-MINORIS; GALAXY-EVOLUTION-EXPLORER; X-RAY; MICROFLARING ACTIVITY; AD LEONIS; SEARCH; RADIO AB The Galaxy Evolution Explorer (GALEX) satellite has obtained high time resolution ultraviolet photometry during a large flare on the M4 dwarf star GJ 3685A. Simultaneous Near-ultraviolet (NUV, 1750 - 2800 angstrom) and Far-ultraviolet (FUV, 1350 - 1750 angstrom) time-tagged photometry with time resolution better than 0.1 s shows that the overall brightness in the FUV band increased by a factor of 1000 in 200 s. Under the assumption that the NUV emission is mostly due to a stellar continuum, and that the FUV flux is shared equally between emission lines and continuum, there is evidence for two distinct flare components for this event. The first flare type is characterized by an exponential increase in flux with little or no increase in temperature. The other involves rapid increases in both temperature and flux. While the decay time for the first flare component may be several hours, the second flare event decayed over less than 1 minute, suggesting that there was little or no confinement of the heated plasma. C1 Catholic Univ Amer, Inst Astrophys & Computat Sci, Washington, DC 20064 USA. Univ Calif Berkeley, Expt Astrophys Grp, Space Sci Lab, Berkeley, CA 94720 USA. CALTECH, Pasadena, CA 91125 USA. Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. Johns Hopkins Univ, Ctr Astrophys Sci, Baltimore, MD 21218 USA. Yonsei Univ, Ctr Space Astrophys, Seoul 120749, South Korea. Lab Astrophys Marseille, F-13376 Marseille, France. Carnegie Inst Washington Observ, Pasadena, CA 91101 USA. NASA, Goddard Space Flight Ctr, Astron & Solar Phys Lab, Greenbelt, MD 20771 USA. RP Robinson, RD (reprint author), Catholic Univ Amer, Inst Astrophys & Computat Sci, 200 Hannan Hall, Washington, DC 20064 USA. EM robinson@opal.gsfc.nasa.gov; wheat@ssl.berkeley.edu; bwelsh@ssl.berkeley.edu OI malina, roger/0000-0003-3399-3865; Salim, Samir/0000-0003-2342-7501 NR 20 TC 28 Z9 28 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 NOV 1 PY 2005 VL 633 IS 1 BP 447 EP 451 DI 10.1086/444608 PN 1 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 977VV UT WOS:000232832500045 ER PT J AU Rappazzo, AF Velli, M Einaudi, G Dahlburg, RB AF Rappazzo, AF Velli, M Einaudi, G Dahlburg, RB TI Diamagnetic and expansion effects on the observable properties of the slow solar wind in a coronal streamer SO ASTROPHYSICAL JOURNAL LA English DT Article DE MHD; solar wind; Sun : corona; Sun : magnetic fields ID KELVIN-HELMHOLTZ INSTABILITIES; DEPENDENT BOUNDARY-CONDITIONS; HELIOSPHERIC CURRENT SHEET; HYPERBOLIC SYSTEMS; SHEAR-LAYER; EVOLUTION; MAGNETOHYDRODYNAMICS; MODEL AB The plasma density enhancements recently observed by the Large-Angle Spectrometric Coronagraph (LASCO) instrument on board the Solar and Heliospheric Observatory (SOHO) spacecraft have sparked considerable interest. In our previous theoretical study of the formation and initial motion of these density enhancements it is found that beyond the helmet cusp of a coronal streamer the magnetized wake configuration is resistively unstable, that a traveling magnetic island develops at the center of the streamer, and that density enhancements occur within the magnetic islands. As the massive magnetic island travels outward, both its speed and width increase. The island passively traces the acceleration of the inner part of the wake. In the present paper a few spherical geometry effects are included, taking into account both the radial divergence of the magnetic field lines and the average expansion undergone by a parcel of plasma propagating outward, using the expanding box model (EBM), and the diamagnetic force due to the overall magnetic field radial gradients, the so-called melon-seed force. It is found that the values of the acceleration and density contrasts can be in good agreement with LASCO observations, provided the spherical divergence of the magnetic lines starts beyond a critical distance from the Sun and the initial stage of the formation and acceleration of the plasmoid is due to the Cartesian evolution of MHD instabilities. This result provides a constraint on the topology of the magnetic field in the coronal streamer. C1 Univ Pisa, Dipartimento Fis, I-56127 Pisa, Italy. Jet Propuls Lab, Pasadena, CA 91109 USA. USN, Res Lab, Computat Phys & Fluid Dynam Lab, Washington, DC 20375 USA. Berkeley Res Associates Inc, Springfield, VA 22150 USA. Univ Florence, Dipartimento Astron & Sci Spazio, I-50125 Florence, Italy. George Mason Univ, Dept Phys & Astron, Fairfax, VA 22030 USA. RP Rappazzo, AF (reprint author), Univ Pisa, Dipartimento Fis, Piazza Torricelli 2, I-56127 Pisa, Italy. EM rappazzo@df.unipi.it; marco.velli@jpl.nasa.gov; einaudi@df.unipi.it; rdahlbur@lcp.nrl.navy.mil NR 23 TC 23 Z9 23 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 NOV 1 PY 2005 VL 633 IS 1 BP 474 EP 488 DI 10.1086/431916 PN 1 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 977VV UT WOS:000232832500049 ER PT J AU Iping, RC Sonneborn, G Gull, TR Massa, DL Hillier, DJ AF Iping, RC Sonneborn, G Gull, TR Massa, DL Hillier, DJ TI Detection of a hot binary companion of eta Carinae SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : eclipsing; circumstellar matter; stars : individual (eta Carinae); stars : mass loss ID ULTRAVIOLET-SPECTROSCOPIC-EXPLORER; ATLAS; VARIABILITY; ABSORPTION; SATELLITE; SPECTRUM; EJECTA; STARS AB We report the detection of a hot companion of eta Carinae using high-resolution spectra (905 - 1180 angstrom) obtained A with the Far Ultraviolet Spectroscopic Explorer (FUSE) satellite. Observations were obtained at two epochs of the 2024 day orbit: 2003 June, during ingress to the 2003.5 X-ray eclipse, and 2004 April, several months after egress. These data show that essentially all the far-UV flux from eta Car shortward of Ly alpha disappeared at least 2 days before the start of the X-ray eclipse (2003 June 29), implying that the hot companion, eta Car B, was also eclipsed by the dense wind or extended atmosphere of eta Car A. Analysis of the far-UV spectrum shows that eta Car B is a luminous, hot star. The N II lambda lambda 1084 - 1086 emission feature suggests that it may be nitrogen-rich. The observed far-UV flux levels and spectral features, combined with the timing of their disappearance, is consistent with eta Car being a massive binary system. C1 NASA, Goddard Space Flight Ctr, Lab Observ Cosmol, Greenbelt, MD 20771 USA. Catholic Univ Amer, Dept Phys, Washington, DC 20064 USA. NASA, Goddard Space Flight Ctr, Lab Exoplanets & Stellar Astrophys, Greenbelt, MD 20771 USA. SGT Inc, Greenbelt, MD 20770 USA. Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. RP Iping, RC (reprint author), NASA, Goddard Space Flight Ctr, Lab Observ Cosmol, Code 665, Greenbelt, MD 20771 USA. EM rosina@taotaomona.gsfc.nasa.gov; george.sonneborn@nasa.gov; theodore.r.gull@nasa.gov; massa@taotaomona.gsfc.nasa.gov; djh@rosella.phyast.pitt.edu RI Gull, Theodore/D-2753-2012 OI Gull, Theodore/0000-0002-6851-5380 NR 21 TC 33 Z9 33 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 NOV 1 PY 2005 VL 633 IS 1 BP L37 EP L40 DI 10.1086/498268 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 977VW UT WOS:000232832600010 ER PT J AU Kashlinsky, A AF Kashlinsky, A TI Cosmic infrared background from Population III stars and its effect on spectra of high-z gamma-ray bursts SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmology : theory; cosmology : observations; diffuse radiation; gamma rays : bursts; gamma rays : theory ID PROBE WMAP OBSERVATIONS; HIGH-ENERGY; 1ST STARS; TENTATIVE DETECTION; UNIVERSE; ANISOTROPIES; CONSTRAINTS; ABSORPTION; TELESCOPE; EVOLUTION AB We discuss the contribution of Population III stars to the near-IR (NIR) cosmic infrared background (CIB) and its effect on spectra of high-z, high-energy gamma-ray bursts (GRBs) and other sources. It is shown that if Population III is composed of massive stars, the claimed NIR CIB excess will be reproduced if only similar to 4% +/- 2% of all baryons went through these stars. Regardless of the precise amount of the NIR CIB due to them, they likely left enough photons to provide a large optical depth for high-energy photons from distant GRBs. Observations of such GRBs are expected following the planned launch of NASA's GLAST mission. Detecting such damping in the spectra of high-z GRBs will then provide important information on the emissions from the Population III epoch, and the location of this cutoff may serve as an indicator of the GRBs' redshifts. We also point out the difficulty of unambiguously detecting the CIB part originating from Population III in spectra of low-z blazars. C1 NASA, Goddard Space Flight Ctr, Observ Cosmol Lab, Greenbelt, MD 20771 USA. Sci Syst & Appl Inc, Lanham, MD 20706 USA. RP Kashlinsky, A (reprint author), NASA, Goddard Space Flight Ctr, Observ Cosmol Lab, Code 665, Greenbelt, MD 20771 USA. EM kashlinsky@stars.gsfc.nasa.gov NR 36 TC 14 Z9 14 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 NOV 1 PY 2005 VL 633 IS 1 BP L5 EP L8 DI 10.1086/498243 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 977VW UT WOS:000232832600002 ER PT J AU Panagia, N Fall, SM Mobasher, B Dickinson, M Ferguson, HC Giavalisco, M Stern, D Wiklind, T AF Panagia, N Fall, SM Mobasher, B Dickinson, M Ferguson, HC Giavalisco, M Stern, D Wiklind, T TI Direct evidence for an early reionization of the universe? SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmology : observations; cosmology : theory; early universe; galaxies : evolution; galaxies : high-redshift; galaxies : individual (UDF 033238.7-274839.8) intergalactic medium ID ULTRA-DEEP-FIELD; STAR-FORMATION; GALAXIES; REDSHIFT; Z-APPROXIMATE-TO-6; Z-SIMILAR-TO-6; EVOLUTION; EPOCH; DUST AB We examine the possible reionization of the intergalactic medium by the source UDF 033238.7 - 274839.8 (hereafter HUDF-JD2), which was discovered in deep HST/VLT/Spitzer images obtained as part of the Great Observatories Origins Deep Survey and Hubble Ultra Deep Field projects. Mobasher et al. have identified HUDF-JD2 as a massive (similar to 6 x 10(11) M circle dot) post-starburst galaxy at redshift z greater than or similar to 6.5. We find that HUDF-JD2 may be capable of reionizing its surrounding region of the universe, starting the process at a redshift as high as z approximate to 15 +/- 5. C1 Space Telescope Sci Inst, Baltimore, MD 21218 USA. European Space Agcy, Dept Space Sci, F-75738 Paris, France. Natl Opt Astron Observ, Tucson, AZ 85726 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Panagia, N (reprint author), Space Telescope Sci Inst, 3700 San Martin Dr, Baltimore, MD 21218 USA. EM panagia@stsci.edu; fall@stsci.edu; mobasher@stsci.edu; mauro@stsci.edu; ferguson@stsci.edu; med@noao.edu; stern@thisvi.jpl.nasa.gov; wiklind@stsci.edu NR 28 TC 18 Z9 18 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 NOV 1 PY 2005 VL 633 IS 1 BP L1 EP L4 DI 10.1086/498094 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 977VW UT WOS:000232832600001 ER PT J AU Lehmer, BD Brandt, WN Alexander, DM Bauer, FE Schneider, DP Tozzi, P Bergeron, J Garmire, GP Giacconi, R Gilli, R Hasinger, G Hornschemeier, AE Koekemoer, AM Mainieri, V Miyaji, T Nonino, M Rosati, P Silverman, JD Szokoly, G Vignali, C AF Lehmer, BD Brandt, WN Alexander, DM Bauer, FE Schneider, DP Tozzi, P Bergeron, J Garmire, GP Giacconi, R Gilli, R Hasinger, G Hornschemeier, AE Koekemoer, AM Mainieri, V Miyaji, T Nonino, M Rosati, P Silverman, JD Szokoly, G Vignali, C TI The extended Chandra Deep Field-South survey: Chandra point-source catalogs SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE cosmology : observations; diffuse radiation; galaxies : active; surveys; X-rays ID CCD IMAGING SPECTROMETER; X-RAY SOURCES; CHARGE-TRANSFER INEFFICIENCY; MEDIUM-SENSITIVITY SURVEY; ACTIVE GALACTIC NUCLEI; NORTH SURVEY; CONFIDENCE-LIMITS; GALAXIES; EXPOSURE; SPECTRA AB We present Chandra point-source catalogs for the Extended Chandra Deep Field - South (E-CDF-S) survey. The E-CDF-S consists of four contiguous 250 ks Chandra observations covering an approximately square region of total solid angle approximate to 0.3 deg(2), which flank the existing approximate to 1 Ms Chandra Deep Field - South (CDF-S). The survey reaches sensitivity limits of approximate to 1.1 x 10(-16) and approximate to 6.7 x 10(-16) ergs cm(-2) s(-1) for the 0.5 - 2.0 and 2 - 8 keV bands, respectively. We detect 762 distinct X-ray point sources within the E-CDF-S exposure; 589 of these sources are new (i.e., not previously detected in the approximate to 1 Ms CDF-S). This brings the total number of X-ray point sources detected in the E-CDF-S region to 915 ( via the E-CDF-S and approximate to 1 Ms CDF-S observations). Source positions are determined using matched-filter and centroiding techniques; the median positional uncertainty is approximate to 0.'' 35. The basic X-ray and optical properties of these sources indicate a variety of source types, although absorbed active galactic nuclei (AGNs) seem to dominate. In addition to our main Chandra catalog, we constructed a supplementary source catalog containing 33 lower significance X-ray point sources that have bright optical counterparts ( R < 23). These sources generally have X-ray - to - optical flux ratios expected for normal and starburst galaxies, which lack a strong AGN component. We present basic number-count results for our main Chandra catalog and find good agreement with the approximate to 1 Ms CDF-S for sources with 0.5 - 2.0 and 2 - 8 keV fluxes greater than 3 x 10(-16) and 1 x 10(-15) ergs cm(-2) s(-1), respectively. Furthermore, three extended sources are detected in the 0.5 - 2.0 keV band, which are found to be likely associated with galaxy groups or poor clusters at z approximate to 0.1-0.7; these have typical rest-frame 0.5 - 2.0 keV luminosities of (1-5) x 10(42) ergs s(-1). C1 Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. Univ Cambridge, Inst Astron, Cambridge CB3 0HA, England. Columbia Univ, Columbia Astrophys Lab, Pupin Labs, New York, NY 10027 USA. Osserv Astron Trieste, INAF, I-34131 Trieste, Italy. Inst Astrophys, F-75014 Paris, France. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Osserv Astrofis Arcetri, INAF, I-50125 Florence, Italy. Max Planck Inst Extraterr Phys, D-85748 Garching, Germany. NASA, Goddard Space Flight Ctr, Lab Xray Astrophys, Greenbelt, MD 20771 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Carnegie Mellon Univ, Dept Phys, Pittsburgh, PA 15213 USA. European So Observ, D-85748 Garching, Germany. Univ Bologna, Dipartimento Astron, I-40127 Bologna, Italy. RP Lehmer, BD (reprint author), Penn State Univ, Dept Astron & Astrophys, 525 Davey Lab, University Pk, PA 16802 USA. RI Vignali, Cristian/J-4974-2012; Brandt, William/N-2844-2015; OI Vignali, Cristian/0000-0002-8853-9611; Brandt, William/0000-0002-0167-2453; Nonino, Mario/0000-0001-6342-9662; Alexander, David/0000-0002-5896-6313; Koekemoer, Anton/0000-0002-6610-2048 NR 61 TC 209 Z9 210 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD NOV PY 2005 VL 161 IS 1 BP 21 EP 40 DI 10.1086/444590 PG 20 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 979XH UT WOS:000232977800003 ER PT J AU Bernstein, MP Sandford, SA Allamandola, LJ AF Bernstein, MP Sandford, SA Allamandola, LJ TI The mid-infrared absorption spectra of neutral polycyclic aromatic hydrocarbons in conditions relevant to dense interstellar clouds SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE infrared : ISM; ISM : lines and bands; ISM : molecules; line : formation; line : identification; molecular data ID SIDE-GROUP ADDITION; COSMIC ICE ANALOGS; INFRARED-SPECTROSCOPY; AMORPHOUS ICE; ASTROPHYSICAL IMPLICATIONS; NITROGEN-HETEROCYCLES; MOLECULAR CLOUDS; CATIONS; CORONENE; PAHS AB Polycyclic aromatic hydrocarbons (PAHs) are common throughout the universe and are expected to be present in dense interstellar clouds. In these environments, some PAHs may be present in the gas phase, but most should be frozen into ice mantles or adsorbed onto dust grains and their spectral features are expected to be seen in absorption. Here we extend our previous work on the infrared spectral properties of the small PAH naphthalene (C10H8) in several media to include the full mid-infrared laboratory spectra of 11 other PAHs and related aromatic species frozen in H2O ices. These include the molecules 1,2-dihydronaphthalene, anthracene, 9,10-dihydroanthracene, phenanthrene, pyrene, benzo[ e] pyrene, perylene, benzo(k) fluoranthene, pentacene, benzo[ghi] perylene, and coronene. These results demonstrate that PAHs and related molecules, as a class, show the same spectral behaviors as naphthalene when incorporated into H2O-rich matrices. When compared to the spectra of these same molecules isolated in inert matrices ( e. g., Ar or N-2), the absorption bands produced when they are frozen in H2O matrices are broader ( factors of 3 - 10), show small position shifts in either direction (usually < 4 cm(-1), always < 10 cm(-1)), and show variable changes in relative band strengths ( typically factors of 1 - 3). There is no evidence of systematic increases or decreases in the absolute strengths of the bands of these molecules when they are incorporated in H2O matrices. In H2O-rich ices, their absorption bands are relatively insensitive to concentration over the range of 10 < H2O/PAH < 200. The absorption bands of these molecules are also insensitive to temperature over the 10 K < T < 125 K range, although the spectra can show dramatic changes as the ices are warmed through the temperature range in which amorphous H2O ice converts to its cubic and hexagonal crystalline forms ( T > 125 K). Given the small observed band shifts cause by H2O, the current database of spectra from Ar matrix - isolated neutral PAHs and related molecules should be useful for the search for these species in dense clouds on the basis of observed absorption band positions. Furthermore, these data permit determination of column densities to better than a factor of 3 for PAHs in dense clouds. Column density determination of detected aromatics to better than a factor of 3 will, however, require good knowledge about the nature of the matrix in which the PAH is embedded and laboratory studies of relevant samples. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Bernstein, MP (reprint author), NASA, Ames Res Ctr, MS 245-6, Moffett Field, CA 94035 USA. EM ssandford@mail.arc.nasa.gov NR 41 TC 30 Z9 30 U1 2 U2 16 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 NOV PY 2005 VL 161 IS 1 BP 53 EP 64 DI 10.1086/432929 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 979XH UT WOS:000232977800005 ER PT J AU Laycock, S Corbet, RHD Coe, MJ Marshall, FE Markwardt, C Lochner, J AF Laycock, S Corbet, RHD Coe, MJ Marshall, FE Markwardt, C Lochner, J TI Long-term behavior of X-ray pulsars in the Small Magellanic Cloud SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE Magellanic Clouds; pulsars : general; stars : neutron; surveys; X-rays : stars ID TIMING-EXPLORER; SPECTRAL-ANALYSIS; AX J0051-733; SMC REGION; DISCOVERY; ACCRETION; BINARIES; CATALOG; STARS; ROSAT AB Results of a 4 yr X-ray monitoring campaign of the Small Magellanic Cloud using the Rossi X-ray Timing Explorer (RXTE) are presented. This large data set makes possible detailed investigation of a significant sample of SMC X-ray binaries. Eight new X-ray pulsars were discovered, and a total of 20 different systems were detected. Spectral and timing parameters were obtained for 18. In the case of 10 pulsars, repeated outbursts were observed, allowing determination of candidate orbital periods for these systems. We also discuss the spatial and pulse-period distributions of the SMC pulsars. C1 Univ Southampton, Sch Phys & Astron, Southampton SO17 1BJ, Hants, England. Ctr Astrophys, Cambridge, MA 02138 USA. NASA, Goddard Space Flight Ctr, Xray Astrophys Lab, Greenbelt, MD 20771 USA. Univ Space Res Assoc, Columbia, MD 21044 USA. Univ Maryland, Dept Astron, College Pk, MD 20742 USA. RP Univ Southampton, Sch Phys & Astron, Southampton SO17 1BJ, Hants, England. NR 69 TC 30 Z9 30 U1 0 U2 1 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 NOV PY 2005 VL 161 IS 1 BP 96 EP 117 DI 10.1086/432884 PG 22 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 979XH UT WOS:000232977800007 ER PT J AU Meier, DL AF Meier, DL TI Magnetically dominated accretion flows (MDAFS) and jet production in the lowhard state SO ASTROPHYSICS AND SPACE SCIENCE LA English DT Article DE black holes; accretion; magnetic fields; jets ID ACTIVE GALACTIC NUCLEI; DOUBLE RADIO-SOURCES; X-RAY BINARY; BLACK-HOLE; RELATIVISTIC JETS; MODEL; DISKS; ELECTRODYNAMICS; ENERGY; M87 AB In this paper I propose that the inner part of a black hole accretion inflow (< 100 r(g)) may enter a magnetically dominated, magnetosphere-like phase in which the strong, well-ordered fields play a more important role than weak, turbulent fields. In the low/hard state this flow is interior to the standard ADAF usually invoked to explain the observed hot, optically thin emission. Preliminary solutions for these new MDAFs are presented. Time-dependent X-ray and radio observations give considerable insight into these processes, and a new interpretation of the X-ray power spectrum (as arising from many disk radii) may be in order. While an evaporative ADAF model explains the noise power above 0.01 Hz, an inner MDAF is needed to explain the high-frequency cutoff near 1 Hz, the presence of a QPO, and the production of a jet. The MDAF scenario also is consistent with the phenomonological models presented at this meeting by several authors. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Meier, DL (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM dlm@sgra.jpl.nasa.gov NR 28 TC 44 Z9 44 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0004-640X J9 ASTROPHYS SPACE SCI JI Astrophys. Space Sci. PD NOV PY 2005 VL 300 IS 1-3 BP 55 EP 65 DI 10.1007/s10509-005-1184-9 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 987QS UT WOS:000233533000007 ER PT J AU Yoon, SC Won, JG Omar, AH Kim, SW Sohn, BJ AF Yoon, SC Won, JG Omar, AH Kim, SW Sohn, BJ TI Estimation of the radiative forcing by key aerosol types in worldwide locations using a column model and AERONET data SO ATMOSPHERIC ENVIRONMENT LA English DT Article DE aerosol direct radiative forcing (ADRF); CRM-2.1.2; AERONET; wavelength-dependent optical properties; ACE-Asia ID COMMUNITY CLIMATE MODEL; ACE-ASIA; SULFATE AEROSOLS; OPTICAL DEPTH; INDIAN-OCEAN; CAMPAIGN; CHINA; GOSAN; DUST AB The aerosol direct radiative forcing (ADRF) is calculated using aerosol robotic network (AERONET) data, and based on aerosol categorization results, the global ADRF is estimated. The CRM-2.1.2, a stand-alone version of the radiative transfer model implemented in NCAR's community climate model, CCM-3.6, is used for the evaluation. A method of determining the aerosol optical parameters is proposed for the ADRF calculation using AERONET data. Linear regression in the log-log plane makes it possible to represent the wavelength-dependent optical properties in the model using AERONET measurements. The local ADRF is estimated at Gosan, Jeju in Korea in Spring from 2001 to 2003, and the ground-based radiation measurements during the ACE-Asia IOP are used to validate the calculation. Using 3 years of AERONET data, the mean forcing efficiency at 500 nm at Gosan in Spring season is evaluated as -80.5 +/- 13.2 Wm(-2) at the surface and -29.9 +/- 4.9 Wm(-2) at the top of atmosphere (TOA). The seasonal variations of the ADRF at eight AERONET sites are calculated from AERONET climatology data. The ADRF calculation at the TOA is compared with the CERES/Terra measurement, and the comparison verifies that the methodology used in this study is suitable for the global ADRF evaluation. Finally, the ADRF values in 14 regions are evaluated. Large ADRF values in Asia and Sahara regions suggest the relative importance of the aerosols on the energy budget in these regions. (c) 2005 Elsevier Ltd. All rights reserved. C1 Korea Meteorol Adm, Seoul 156720, South Korea. Seoul Natl Univ, Sch Earth & Environm Sci, Seoul 151747, South Korea. NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Won, JG (reprint author), Korea Meteorol Adm, Seoul 156720, South Korea. EM wonjg@kma.go.kr RI Omar, Ali/D-7102-2017 OI Omar, Ali/0000-0003-1871-9235 NR 25 TC 32 Z9 32 U1 0 U2 10 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1352-2310 J9 ATMOS ENVIRON JI Atmos. Environ. PD NOV PY 2005 VL 39 IS 35 BP 6620 EP 6630 DI 10.1016/j.atmosenv.2005.07.058 PG 11 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 980QA UT WOS:000233032000014 ER PT J AU Freed, AD Einstein, DR Vesely, I AF Freed, AD Einstein, DR Vesely, I TI Invariant formulation for dispersed transverse isotropy in aortic heart valves - An efficient means for modeling fiber splay SO BIOMECHANICS AND MODELING IN MECHANOBIOLOGY LA English DT Article ID STRUCTURAL CONSTITUTIVE MODEL; FINITE ELASTICITY; BEHAVIOR; TISSUE AB Most soft tissues possess an oriented architecture of collagen fiber bundles, conferring both anisotropy and nonlinearity to their elastic behavior. Transverse isotropy has often been assumed for a subset of these tissues that have a single macroscopically-identifiable preferred fiber direction. Micro-structural studies, however, suggest that, in some tissues, collagen fibers are approximately normally distributed about a mean preferred fiber direction. Structural constitutive equations that account for this dispersion of fibers have been shown to capture the mechanical complexity of these tissues quite well. Such descriptions, however, are computationally cumbersome for two-dimensional (2D) fiber distributions, let alone for fully three-dimensional (3D) fiber populations. In this paper, we develop a new constitutive law for such tissues, based on a novel invariant theory for dispersed transverse isotropy. The invariant theory is derived from a novel closed-form 'splay invariant' that can easily handle 3D fiber populations, and that only requires a single parameter in the 2D case. The model fits biaxial data for aortic valve tissue as accurately as the standard structural model. Modification of the fiber stress-strain law requires no reformulation of the constitutive tangent matrix, making the model flexible for different types of soft tissues. Most importantly, the model is computationally expedient in a finite-element analysis, demonstrated by modeling a bloprosthetic heart valve. C1 Cleveland Clin Fdn, Dept Biomed Engn, Cleveland, OH 44195 USA. NASA, John H Glenn Res Ctr Lewis Field, BioSci & Technol Branch, Cleveland, OH 44135 USA. Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99354 USA. Childrens Hosp Los Angeles, Saban Res Inst, Los Angeles, CA 90027 USA. RP Freed, AD (reprint author), Cleveland Clin Fdn, Dept Biomed Engn, ND-20,9500 Euclid Ave, Cleveland, OH 44195 USA. EM Alan.D.Freed@nasa.gov; Daniel.Einstein@pnl.gov; IVesely@chla.usc.edu OI Freed, Alan/0000-0002-3492-0628 NR 33 TC 55 Z9 55 U1 1 U2 9 PU SPRINGER HEIDELBERG PI HEIDELBERG PA TIERGARTENSTRASSE 17, D-69121 HEIDELBERG, GERMANY SN 1617-7959 J9 BIOMECH MODEL MECHAN JI Biomech. Model. Mechanobiol. PD NOV PY 2005 VL 4 IS 2-3 BP 100 EP 117 DI 10.1007/s10237-005-0069-8 PG 18 WC Biophysics; Engineering, Biomedical SC Biophysics; Engineering GA 994MX UT WOS:000234037000003 PM 16133588 ER PT J AU Kaur, I Simons, ER Castro, VA Ott, CM Pierson, DL AF Kaur, I Simons, ER Castro, VA Ott, CM Pierson, DL TI Changes in monocyte functions of astronauts SO BRAIN BEHAVIOR AND IMMUNITY LA English DT Article DE stress; monocytes; immune system; weightlessness; spaceflight; microgravity; monocyte function; immune defense ID EPSTEIN-BARR-VIRUS; SPACE-FLIGHT; IMMUNE-SYSTEM; SPACEFLIGHT; RESPONSES; REACTIVATION; DEGRANULATION; NEUTROPHILS; RECEPTORS AB As part of the systematic evaluation of the innate immune system for long duration missions, this study focused on the antimicrobial functions of monocytes in astronauts participating in spaceflight. The study included four space shuttle missions and 25 astronauts. Nine non-astronauts served as controls. Blood specimens were collected 10 days before launch, within 3 h after landing, and again 3 days after landing. The number of monocytes did not differ significantly over the interval sampled in both the astronaut or control groups. However, following 5-11 days of spaceflight, the astronauts' monocytes exhibited reductions in ability to engulf Escherichia coli, elicit an oxidative burst, and degranulate. The phagocytic index was significantly reduced following spaceflight when compared to control values. This reduction in phagocytosis was accompanied by changes in the expression of two surface markers involved in phagocytosis, CD32 and CD64. Levels of cortisol, epinephrine, and norepinephrine after spaceflight did not increase over preflight values. (c) 2005 Published by Elsevier Inc. C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Enterprise Advisory Serv Inc, Houston, TX 77058 USA. Boston Univ, Sch Med, Dept Biochem, Boston, MA 02118 USA. RP Pierson, DL (reprint author), NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. EM ikaur@mdanderson.org; dpierson@ems.jsc.nasa.gov NR 32 TC 53 Z9 57 U1 1 U2 10 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0889-1591 J9 BRAIN BEHAV IMMUN JI Brain Behav. Immun. PD NOV PY 2005 VL 19 IS 6 BP 547 EP 554 DI 10.1016/j.bbi.2004.12.006 PG 8 WC Immunology; Neurosciences SC Immunology; Neurosciences & Neurology GA 978IE UT WOS:000232866000010 PM 15908177 ER PT J AU Vander Wal, RL Tomasek, AJ King, JD AF Vander Wal, RL Tomasek, AJ King, JD TI A method for structural characterization of the range of cylindrical nanocarbons: Nanotubes to nanofibers SO CARBON LA English DT Article DE carbon nanotube; nanofiber; HRTEM; nanostructure; image analysis ID NI-CATALYZED NANOFIBERS; CARBON NANOTUBES; FLAME SYNTHESIS; ELECTRON-MICROSCOPY; RAMAN-SPECTROSCOPY; FULLERENES; IMAGES AB Given the wealth of carbon multi-walled carbon nanotubes (MWNTs) and nanofiber synthesis strategies and resulting forms, there is an increasing need to better classify these materials in terms of their nanostructure. Apart from distinguishing the different nanoforms, such classification may be particularly useful for relating MWNT or nanofiber performance within various application,to their nanostructure. Demonstrated here is the use of image analysis algorithms applied to high resolution transmission electron microscopy (HRTEM) images of MWNTs and nanofibers. The analysis of the HRTEM images allowed for four separate measurements to quantify the graphitic content of the nanotube and nanofiber samples. Each measurement was based upon the features of individual carbon layer plane segments, which appear as fringes in HRTEM images. These measures included fringe length, separation, tortuosity and orientation. Distributions in the form of histograms serve to quantify data contained in the HRTEM images as represented by these parameters. Such information can serve as a measure of the physical characteristics and resulting chemical and mechanical properties of the nanotubes, nanofibers and their utility in applications. (C) 2005 Elsevier Ltd. All rights reserved. C1 NASA, Glenn Res Ctr, NCSER, Cleveland, OH 44135 USA. RP Vander Wal, RL (reprint author), NASA, Glenn Res Ctr, NCSER, MS 110-3,21000 Brookpk Rd, Cleveland, OH 44135 USA. EM randy@rvander.grc.nasa.gov NR 38 TC 5 Z9 5 U1 0 U2 9 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0008-6223 J9 CARBON JI Carbon PD NOV PY 2005 VL 43 IS 14 BP 2918 EP 2930 DI 10.1016/j.carbon.2005.06.026 PG 13 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 978BE UT WOS:000232846400012 ER PT J AU Zak, M AF Zak, M TI From reversible thermodynamics to life SO CHAOS SOLITONS & FRACTALS LA English DT Article ID DYNAMICS AB The First Principle for dynamics of living systems has been proposed and discussed. It is based upon introduction of information potential that couples the Newtonian dynamics and the corresponding Liouville equation in the same way in which the quantum potential couples the Madelung equations in quantum mechanics. It has been demonstrated that the information potential can generate a negative diffusion that reverses the evolution towards decrease of entropy. Mathematical, physical and biological interpretations of the information potential are discussed. An algorithm for life-nonlife discrimination is proposed. An associated Boolean approach is introduced to simulate the evolution of intelligence. (c) 2005 Elsevier Ltd. All rights reserved. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Zak, M (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM mzak@jpl.nasa.gov NR 16 TC 9 Z9 9 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0960-0779 J9 CHAOS SOLITON FRACT JI Chaos Solitons Fractals PD NOV PY 2005 VL 26 IS 4 BP 1019 EP 1033 DI 10.1016/j.chaos.2005.02.010 PG 15 WC Mathematics, Interdisciplinary Applications; Physics, Multidisciplinary; Physics, Mathematical SC Mathematics; Physics GA 936RZ UT WOS:000229874400001 ER PT J AU Dietrich, DL Struk, PM Ikegami, M Xu, G AF Dietrich, DL Struk, PM Ikegami, M Xu, G TI Single droplet combustion of decane in microgravity: experiments and numerical modelling SO COMBUSTION THEORY AND MODELLING LA English DT Article DE droplet combustion; microgravity ID EXTINCTION; DIFFUSION; TRANSPORT; CHEMISTRY; FLAMES; MASS AB This paper presents experimental data on single droplet combustion of decane in microgravity and compares the results to a numerical model. The primary independent experiment variables are the ambient pressure and oxygen mole fraction, pressure, droplet size (over a relatively small range) and ignition energy. The droplet history (D-2 history) is non-linear with the burning rate constant increasing throughout the test. The average burning rate constant, consistent with classical theory, increased with increasing ambient oxygen mole fraction and was nearly independent of pressure, initial droplet size and ignition energy. The flame typically increased in size initially, and then decreased in size, in response to the shrinking droplet. The flame standoff increased linearly for the majority of the droplet lifetime. The flame surrounding the droplet extinguished at a finite droplet size at lower ambient pressures and an oxygen mole fraction of 0.15. The extinction droplet size increased with decreasing pressure. The model is transient and assumes spherical symmetry, constant thermo-physical properties (specific heat, thermal conductivity and species Lewis number) and single step chemistry. The model includes gas-phase radiative loss and a spherically symmetric, transient liquid phase. The model accurately predicts the droplet and flame histories of the experiments. Good agreement requires that the ignition in the experiment be reasonably approximated in the model and that the model accurately predict the pre-ignition vaporization of the droplet. The model does not accurately predict the dependence of extinction droplet diameter on pressure, a result of the simplified chemistry in the model. The transient flame behaviour suggests the potential importance of fuel vapour accumulation. The model results, however, show that the fractional mass consumption rate of fuel in the flame relative to the fuel vaporized is close to 1.0 for all but the lowest ambient oxygen mole fractions. C1 NASA, John H Glenn Res Ctr, Cleveland, OH 44135 USA. Natl Inst Adv Ind Sci & Technol, Hokkaido, Japan. RP Dietrich, DL (reprint author), NASA, John H Glenn Res Ctr, Cleveland, OH 44135 USA. EM daniel.dietrich@grc.nasa.gov RI Struk, Peter/M-1651-2013 OI Struk, Peter/0000-0001-8221-8369 NR 27 TC 10 Z9 11 U1 0 U2 10 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 1364-7830 J9 COMBUST THEOR MODEL JI Combust. Theory Model. PD NOV PY 2005 VL 9 IS 4 BP 569 EP 585 DI 10.1080/13647830500256039 PG 17 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Mathematics, Interdisciplinary Applications SC Thermodynamics; Energy & Fuels; Engineering; Mathematics GA 985XQ UT WOS:000233412400002 ER PT J AU Raskin, RG Pan, MJ AF Raskin, RG Pan, MJ TI Knowledge representation in the semantic web for Earth and environmental terminology (SWEET) SO COMPUTERS & GEOSCIENCES LA English DT Article DE ontology; classification; semantics; search; discovery AB The semantic web for Earth and environmental terminology (SWEET) is an investigation in improving discovery and use of Earth science data, through software understanding of the semantics of web resources. Semantic understanding is enabled through the use of ontologics, or formal representations of technical concepts and their interrelations in a form that supports domain knowledge. The ultimate vision of the semantic web consists of web pages with XML namespace tags around terms, enabling search tools to ascertain their meanings by following the link to the defining ontologies. Such a scenario both reduces the number of false hits (where a search returns alternative, unintended meanings of a term) and increases the number of successful hits (where searcher and information provider have a syntax mismatch of the same concept). For SWEET, we developed a collection of ontologies using the web ontology language (OWL) that include both orthogonal concepts (space, time, Earth realms, physical quantities, etc.) and integrative science knowledge concepts (phenomena, events, etc.). This paper describes the development of a knowledge space for Earth system science and related concepts (such as data properties). Some of the ontology contents are "virtual" by means of an OWL wrapper associated with terms in large external databases (including gazetteers and Earthquake databases). We developed a search tool that finds alternative search terms (based on the semantics) and redirects the expanded set of terms to a search engine. (C) 2005 Elsevier Ltd. All rights reserved. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Raskin, RG (reprint author), CALTECH, Jet Prop Lab, Mail Code 300-320, Pasadena, CA 91109 USA. EM raskin@seastar.jpl.nasa.gov NR 19 TC 118 Z9 120 U1 3 U2 17 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0098-3004 J9 COMPUT GEOSCI-UK JI Comput. Geosci. PD NOV PY 2005 VL 31 IS 9 BP 1119 EP 1125 DI 10.1016/j.cageo.2004.12.004 PG 7 WC Computer Science, Interdisciplinary Applications; Geosciences, Multidisciplinary SC Computer Science; Geology GA 976RH UT WOS:000232750400005 ER PT J AU Carrasco-Nunez, G Righter, K Chesley, J Siebert, L Aranda-Gomez, J AF Carrasco-Nunez, G Righter, K Chesley, J Siebert, L Aranda-Gomez, J TI Contemporaneous eruption of calc-alkaline and alkaline lavas in a continental arc (Eastern Mexican Volcanic Belt): chemically heterogeneous but isotopically homogeneous source SO CONTRIBUTIONS TO MINERALOGY AND PETROLOGY LA English DT Article DE Mexican Volcanic Belt; assimilation and fractional crystallization; hawaiite; calc-alkaline lavas; degree of melting; mantle source ID SUBDUCTION ZONE MAGMATISM; TRACE-ELEMENT; BASALTIC ANDESITES; WESTERN MEXICO; PB-ISOTOPE; COMPOSITIONAL DIVERSITY; QUATERNARY VOLCANISM; MANTLE METASOMATISM; WASHINGTON CASCADES; SOUTHERN WASHINGTON AB Nearly contemporaneous eruption of alkaline and calc-alkaline lavas occurred about 900 years BP from El Volcancillo paired vent, located behind the volcanic front in the Mexican Volcanic Belt (MVB). Emission of hawaiite (Toxtlacuaya) was immediately followed by calc-alkaline basalt (Rio Naolinco). Hawaiites contain olivine microphenocrysts (Fo(67-72)), plagioclase (An(56-60)) phenocrysts, have 4-5 wt% MgO and 49.6-50.9 wt% SiO(2). In contrast, calc-alkaline lavas contain plagioclase (An(64-72)) and olivine phenocrysts (Fo(81-84)) with spinel inclusions, and have 8-9 wt% MgO and 48.4-49.4 wt% SiO(2). The most primitive lavas in the region (Rio Naolinco and Cerro Colorado) are not as primitive as parental melts in other arcs, and could represent either (a) variable degrees of melting of a subduction modified, garnet-bearing depleted mantle source, followed by AFC process, or (b) melting of two distinct mantle sources followed by AFC processes. These two hypotheses are evaluated using REE, HFSE, and Sr, Os and Pb isotopic data. The Toxtlacuaya flow and the Y & I lavas can be generated by combined fractional crystallization and assimilation of gabbroic granulite, starting with a parental liquid similar to the Cerro Colorado basalt. Although calc-alkaline and alkaline magmas commonly occur together in other areas of the MVB, evidence for subduction component in El Volcancillo magmas is minimal and limited to < 1%, which is a unique feature in this region further from the trench. El Volcancillo lavas were produced from two different magma batches: we surmise that the injection of calc-alkaline magma into an alkaline magma chamber triggered the eruption of hawaiites. Our results suggest that the subalkaline and hawaiitic lavas were formed by different degrees of partial melting of a similar, largely depleted mantle source, followed by later AFC processes. This model is unusual for arcs, where such diversity is usually explained by melting of heterogeneous (enriched and depleted) and subduction-modified mantle. C1 Univ Nacl Autonoma Mexico, Ctr Geociencias, Queretaro 76230, Mexico. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Univ Arizona, Dept Geosci, Tucson, AZ 85721 USA. Smithsonian Inst, Global Volcanism Program, Washington, DC 20013 USA. RP Carrasco-Nunez, G (reprint author), Univ Nacl Autonoma Mexico, Ctr Geociencias, Campus Juriquilla, Queretaro 76230, Mexico. EM gerardoc@geociencias.unam.mx NR 69 TC 17 Z9 17 U1 0 U2 7 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0010-7999 J9 CONTRIB MINERAL PETR JI Contrib. Mineral. Petrol. PD NOV PY 2005 VL 150 IS 4 BP 423 EP 440 DI 10.1007/s00410-005-0015-x PG 18 WC Geochemistry & Geophysics; Mineralogy SC Geochemistry & Geophysics; Mineralogy GA 977HC UT WOS:000232793000004 ER PT J AU Potter, C Tan, PN Kumar, V Kucharik, C Klooster, S Genovese, V Cohen, W Healey, S AF Potter, C Tan, PN Kumar, V Kucharik, C Klooster, S Genovese, V Cohen, W Healey, S TI Recent history of large-scale ecosystem disturbances in North America derived from the AVHRR satellite record SO ECOSYSTEMS LA English DT Article DE ecosystem disturbance; remote sensing; fire; drought; forests ID LAND-USE CHANGE; TERRESTRIAL ECOSYSTEMS; BRAZILIAN AMAZON; CARBON; BIOMASS; EMISSIONS; FIRE; DEFORESTATION; VARIABILITY; FORESTS AB Ecosystem structure and function are strongly affected by disturbance events, many of which in North America are associated with seasonal temperature extremes, wildfires, and tropical storms. This study was conducted to evaluate patterns in a 19-year record of global satellite observations of vegetation phenology from the advanced very high resolution radiometer (AVHRR) as a means to characterize major ecosystem disturbance events and regimes. The fraction absorbed of photosynthetically active radiation (FPAR) by vegetation canopies worldwide has been computed at a monthly time interval from 1982 to 2000 and gridded at a spatial resolution of 8-km globally. Potential disturbance events were identified in the FPAR time series by locating anomalously low values (FPAR-LO) that lasted longer than 12 consecutive months at any 8-km pixel. We can find verifiable evidence of numerous disturbance types across North America, including major regional patterns of cold and heat waves, forest fires, tropical storms, and large-scale forest logging. Summed over 19 years, areas potentially influenced by major ecosystem disturbances (one FPAR-LO event over the period 1982-2000) total to more than 766,000 km(2). The periods of highest detection frequency were 1987-1989, 1995-1997, and 1999. Sub-continental regions of the Pacific Northwest, Alaska, and Central Canada had the highest proportion (> 90%) of FPAR-LO pixels detected in forests, tundra shrublands, and wetland areas. The Great Lakes region showed the highest proportion (39%) of FPAR-LO pixels detected in cropland areas, whereas the western United States showed the highest proportion (16%) of FPAR-LO pixels detected in grassland areas. Based on this analysis, an historical picture is emerging of periodic droughts and heat waves, possibly coupled with herbivorous insect outbreaks, as among the most important causes of ecosystem disturbance in North America. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Univ Minnesota, Minneapolis, MN 55415 USA. Univ Wisconsin, Madison, WI 53706 USA. Calif State Univ Monterey Bay, Seaside, CA 93955 USA. US Forest Serv, USDA, Corvallis, OR 97331 USA. RP Potter, C (reprint author), NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. EM cpotter@mail.arc.nasa.gov OI Kucharik, Christopher/0000-0002-0400-758X NR 49 TC 28 Z9 29 U1 2 U2 20 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 1432-9840 J9 ECOSYSTEMS JI Ecosystems PD NOV PY 2005 VL 8 IS 7 BP 808 EP 824 DI 10.1007/s10021-005-0041-6 PG 17 WC Ecology SC Environmental Sciences & Ecology GA 984TF UT WOS:000233326500006 ER PT J AU De Young, RJ Grant, VB Severance, K AF De Young, RJ Grant, VB Severance, K TI Aerosol transport in the California Central Valley observed by airborne lidar SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID SAN-JOAQUIN VALLEY; AIR AB An aerosol lidar system was deployed on the NASA DC-8 and used to measure aerosol vertical profiles in the California Central Valley. The nadir-pointing Nd:YAG lidar operated at 532 and 1064 nm at 20 Hz. The resulting aerosol profiles were plotted in a unique three-dimensional format that allowed the visual observation of the aerosol scattering ratio profiles, the valley topography, and corresponding backward trajectory air masses. The accumulation of aerosols from the Bakersfield area can be seen in the southern end of the valley due to topography and prevailing winds. C1 NASA, Langley Res Ctr, Sci Directorate, Hampton, VA 23681 USA. NASA, Langley Res Ctr, Syst Engn Directorate, Hampton, VA 23681 USA. Sunlight Nutr & Hlth Res, San Francisco, CA 94109 USA. RP De Young, RJ (reprint author), NASA, Langley Res Ctr, Sci Directorate, Hampton, VA 23681 USA. EM russell.j.deyoung@nasa.gov OI Grant, William/0000-0002-1439-3285 NR 15 TC 8 Z9 8 U1 0 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD NOV 1 PY 2005 VL 39 IS 21 BP 8351 EP 8357 DI 10.1021/es0487401 PG 7 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 981HJ UT WOS:000233078000040 PM 16294873 ER PT J AU Bar-Cohen, Y AF Bar-Cohen, Yoseph TI Current and future developments in artificial muscles using electroactive polymers SO EXPERT REVIEW OF MEDICAL DEVICES LA English DT Review DE artificial muscles; biomimetics; EAP electroactive polymers; polymer actuators; robotics AB For decades, electroactive polymers received relatively little attention due to their limited actuation capability. However, in the last 15 years, a series of electroactive polymer materials have emerged that produce a significant shape or size change in response to electrical stimulation. These materials have the closest functional similarity to biologic muscles, enabling the engineering of novel capabilities that were, up until recently, impossible to achieve. Efforts are underway to address the many challenges that are hampering the practical application of these materials, and recent progress has already led to dramatic capability improvements. Various novel mechanisms and devices were demonstrated including robotic fish, catheter steering elements, robotic arms, miniature grippers, loudspeakers, active diaphragms, Braille display and dust-wipers. For developers of future medical devices, these materials are offering numerous advantages for their flexibility, fracture toughness and controllability, as well as low mass and low power requirements. This article provides a review of the current status, challenges and potential near-future applications of these materials. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Bar-Cohen, Y (reprint author), CALTECH, Jet Prop Lab, MS 67-119,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM yosi@jpl.nasa.gov NR 24 TC 13 Z9 13 U1 9 U2 50 PU FUTURE DRUGS LTD PI LONDON PA UNITEC HOUSE, 3RD FL, 2 ALBERT PLACE, FINCHLEY CENTRAL, LONDON N3 1QB, ENGLAND SN 1743-4440 J9 EXPERT REV MED DEVIC JI Expert Rev. Med. Devices PD NOV PY 2005 VL 2 IS 6 BP 731 EP 740 DI 10.1586/17434440.2.6.731 PG 10 WC Engineering, Biomedical SC Engineering GA 089YS UT WOS:000240918400014 PM 16293100 ER PT J AU Lehnert, H Stone, R Heimler, W AF Lehnert, H Stone, R Heimler, W TI A new species of Polymastia (Porifera, Hadromerida, Polymastiidae) from the Aleutian Islands, Alaska, USA SO FACIES LA English DT Article DE porifera; hadromerida; Polymastia; new species; taxonomy; Aleutian Islands AB Polymastia fluegeli n. sp. is described from deep water off the Aleutian Islands (Alaska, USA). P. fluegeli is disc-shaped and lives partly buried in the sediment, with only the papillae protruding above the surface. This new species has a basal layer of agglutinated sediment particles occurring between the choanosome and the ectosomal lower layer. This conspicuous sediment layer is not described for other species of Polymastia. Occurring spicule types and sizes are different from known species of the area. C1 Natl Marine Fisheries Serv, Auke Bay Lab, Juneau, AK 99801 USA. Inst Zool 1, D-91058 Erlangen, Germany. RP Lehnert, H (reprint author), Eichenstr 4, D-86507 Oberottmarshausen, Germany. EM Helm.Lehnert@t-online.de NR 12 TC 6 Z9 6 U1 0 U2 2 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0172-9179 J9 FACIES JI Facies PD NOV PY 2005 VL 51 IS 1-4 BP 49 EP 52 DI 10.1007/s10347-005-0047-8 PG 4 WC Geology; Paleontology SC Geology; Paleontology GA 007XQ UT WOS:000235005200007 ER PT J AU Heifetz, J Wing, BL Stone, RP Malecha, PW Courtney, DL AF Heifetz, J Wing, BL Stone, RP Malecha, PW Courtney, DL TI Corals of the Aleutian Islands SO FISHERIES OCEANOGRAPHY LA English DT Article DE Aleutian Islands; coral; habitat; species diversity; sponge ID DEEP-SEA; PRIMNOA-RESEDAEFORMIS; ALASKA; HABITAT; GROWTH; GULF AB A unique feature of the benthic habitat in the Aleutian Islands is the presence of a highly diverse and abundant coral and sponge community. These communities likely provide important habitat for a variety of fish and invertebrate species. Summaries of historical data and recent direct observations with a submersible indicate that the Aleutian Islands may harbour the highest diversity and abundance of coldwater corals in the world. There are 69 documented taxa (species and subspecies) of coral in the Aleutians of which 25 are endemic. Within the Aleutian Islands, there is an increase in diversity of corals west of about longitude 169 degrees W. This shift in diversity is consistent with the hypothesis of an ecological boundary in the vicinity of Samalga Pass. Given the endemism and high diversity and abundance of corals in the Aleutians, there is evidence that this region is the evolutionary centre of origin for some taxa of coldwater corals. C1 Alaska Fisheries Sci Ctr, Natl Marine Fisheries Serv, Auke Bay Lab, Juneau, AK 99801 USA. RP Heifetz, J (reprint author), Alaska Fisheries Sci Ctr, Natl Marine Fisheries Serv, Auke Bay Lab, 11305 Glacier Highway, Juneau, AK 99801 USA. EM jon.heifetz@noaa.gov NR 17 TC 33 Z9 38 U1 2 U2 7 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 1054-6006 EI 1365-2419 J9 FISH OCEANOGR JI Fish Oceanogr. PD NOV PY 2005 VL 14 SU 1 BP 131 EP 138 DI 10.1111/j.1365-2419.2005.00371.x PG 8 WC Fisheries; Oceanography SC Fisheries; Oceanography GA 968GG UT WOS:000232149300009 ER PT J AU Rose, CS Stoner, AW Matteson, K AF Rose, CS Stoner, AW Matteson, K TI Use of high-frequency imaging sonar to observe fish behaviour near baited fishing gears SO FISHERIES RESEARCH LA English DT Article DE longline; fish pot; bait; acoustic camera; behaviour; sablefish; halibut ID PACIFIC HALIBUT; UNDERWATER OBSERVATIONS; STOCK ASSESSMENT; DENSITY; VIDEO; TRAP; ATTRACTION; LONGLINES; ABUNDANCE; CAMERA AB A high-frequency imaging acoustic camera was used to observe the behaviour of sablefish (Anoplopoma fimbria) and Pacific halibut (Hippoglossus stenolepis) around baited fish pots and baited hooks in the deep shelf environment (220-366 m depth) off Oregon. The acoustic camera, tested to a distance of 9.7 m (11.5-15.6 m(2) field of view), provided continuous high-resolution imagery of approaches of fish to the gear, entry into pot tunnels, bait attacks, and escapes in conditions of darkness and high turbidity. Fish inside and beyond the fish pot could also be observed. Fishes, including small individuals and "bait thieves" (> 20 cm), could be measured and tracked in the digital images. Concurrent observations with a low-light video camera and infrared lighting yielded a field of view of approximately 1 m2, limited to just one side of the fish pot. A large proportion of the video tape produced was unusable because of turbidity, and the patterns of fish movement around the pots and baited hooks were poorly characterized by the video camera. The large field of view provided by the acoustic camera showed that a very low percentage of sablefish and halibut approaching the gear were captured. Observations on different gear types, including fish pots with and without tunnel triggers, provide insights into how acoustic camera imagery can be used to improve our understanding of fish behaviour in the natural environment, to design increasingly selective and efficient fishing gear, and to improve bait-dependent stock assessments. (c) 2005 Elsevier B.V. All rights reserved. C1 NOAA, Natl Marine Fisheries Serv, Fisheries Behav Ecol Program, Alaska Fisheries Sci Ctr, Newport, OR 97365 USA. NOAA, Natl Marine Fisheries Serv, Alaska Fisheries Sci Ctr, Seattle, WA 98115 USA. Oregon Dept Fish & Wildlife, Newport, OR 97365 USA. RP Stoner, AW (reprint author), NOAA, Natl Marine Fisheries Serv, Fisheries Behav Ecol Program, Alaska Fisheries Sci Ctr, 2030 SE Marine Sci Dr, Newport, OR 97365 USA. EM al.stoner@noaa.gov NR 29 TC 20 Z9 21 U1 3 U2 16 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0165-7836 J9 FISH RES JI Fish Res. PD NOV PY 2005 VL 76 IS 2 BP 291 EP 304 DI 10.1016/j.fishres.2005.07.015 PG 14 WC Fisheries SC Fisheries GA 972BQ UT WOS:000232429200012 ER PT J AU Havelund, K Rosu, G AF Havelund, K Rosu, G TI Foreword SO FORMAL METHODS IN SYSTEM DESIGN LA English DT Editorial Material C1 NASA, Ames Res Ctr, Kestrel Technol, Moffett Field, CA 94035 USA. Univ Illinois, Champaign, IL 61820 USA. RP Havelund, K (reprint author), NASA, Ames Res Ctr, Kestrel Technol, Moffett Field, CA 94035 USA. NR 0 TC 0 Z9 0 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 NOV PY 2005 VL 27 IS 3 BP 211 EP 212 DI 10.1007/s10703-005-3397-5 PG 2 WC Computer Science, Theory & Methods SC Computer Science GA 996VV UT WOS:000234204200001 ER PT J AU Elser, JJ Schampel, JH Garcia-Pichel, F Wade, BD Souza, V Eguiarte, L Escalante, A Farmer, JD AF Elser, JJ Schampel, JH Garcia-Pichel, F Wade, BD Souza, V Eguiarte, L Escalante, A Farmer, JD TI Effects of phosphorus enrichment and grazing snails on modern stromatolitic microbial communities SO FRESHWATER BIOLOGY LA English DT Article DE nutrient limitation; phosphorus; snails; stoichiometry; stream; stromatolites ID GEL-ELECTROPHORESIS ANALYSIS; 16S RIBOSOMAL-RNA; N-P RATIOS; ECOLOGICAL STOICHIOMETRY; BENTHIC CYANOBACTERIA; CHEMICAL-COMPOSITION; CARBONATE SEDIMENTS; TROPHIC CASCADES; FLORIDA BAY; FOOD WEBS AB 1. The effects of phosphorus enrichment and grazing snails on a benthic microbial community that builds stromatolic oncolites were examined in an experiment at Rio Mesquites, Cuatro Cienegas, Mexico. Chemical analyses of stream water samples indicated that overall atomic ratios of total nitrogen (N) to total phosphorus (P) were approximately 110, indicating a strong potential for P-limitation of microbial growth. 2. Phosphorus enrichment involved addition of 5 mu mol Na(2)HPO(4) L(-1) to streamside microcosms receiving intermittent inputs of stream water while grazer manipulation involved removal of the dominant grazer, the snail Mexithauma quadripaludium. After 7 weeks, we examined responses in organic matter content, C : N : P ratios, metabolism (P removal, primary production, dark respiration, and calcification), and microbial community structure using molecular fingerprinting of 16S rRNA genes. 3. Manipulation of snails did not affect response variables measured in these treatments (organic matter, C : P ratio, P removal rate). However, P enrichment significantly decreased the C : P and N : P ratios of surficial materials in the oncolites (organic matter content was unchanged), increased net and gross photosynthesis (oxygen consumption in the dark was unchanged), increased rates of calcification, and increased diatoms relative to cyanobacteria. Heterotrophic Eubacteria and Archaea were only modestly affected. Thus, our results indicate weak grazing effects but strong impacts of P in this benthic system. 4. We hypothesise that a state of severe P-limitation is imposed on autotrophic production in this food web due, at least in part, to co-precipitation of phosphate during calcite deposition. This produces severe P-limitation of the benthic algae and cyanobacteria, resulting in high C : P ratio of microbial mats relative to the biomass of photoautotrophs (phytoplankton, terrestrial foliage) in other ecosystems. In turn, this high C : P ratio is likely to generate severe stoichiometric constraints on the herbivores, thus limiting their populations and resulting in weak overall grazing impacts. C1 Arizona State Univ, Sch Life Sci, Tempe, AZ 85287 USA. Univ Nacl Autonoma Mexico, Inst Ecol, Dept Ecol & Evolut, Mexico City, DF, Mexico. Arizona State Univ, Dept Geol Sci, Tempe, AZ USA. NASA, Astrobiol Inst, Moffett Field, CA USA. RP Elser, JJ (reprint author), Arizona State Univ, Sch Life Sci, Tempe, AZ 85287 USA. EM j.elser@asu.edu RI Elser, James/A-7082-2008; Escalante, Ana /D-5479-2011; OI Elser, James/0000-0002-1460-2155; Escalante, Ana /0000-0001-8147-4598; Wade, Brian D./0000-0001-8251-0386 NR 76 TC 51 Z9 53 U1 2 U2 27 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0046-5070 J9 FRESHWATER BIOL JI Freshw. Biol. PD NOV PY 2005 VL 50 IS 11 BP 1808 EP 1825 DI 10.1111/j.1365-2427.2005.01451.x PG 18 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 975JK UT WOS:000232657900004 ER PT J AU Lefsky, MA Harding, DJ Keller, M Cohen, WB Carabajal, CC Espirito-Santo, FD Hunter, MO de Oliveira, R AF Lefsky, MA Harding, DJ Keller, M Cohen, WB Carabajal, CC Espirito-Santo, FD Hunter, MO de Oliveira, R TI Estimates of forest canopy height and aboveground biomass using ICESat SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID ATMOSPHERE; LIDAR AB Exchange of carbon between forests and the atmosphere is a vital component of the global carbon cycle. Satellite laser altimetry has a unique capability for estimating forest canopy height, which has a direct and increasingly well understood relationship to aboveground carbon storage. While the Geoscience Laser Altimeter System (GLAS) onboard the Ice, Cloud and land Elevation Satellite (ICESat) has collected an unparalleled dataset of lidar waveforms over terrestrial targets, processing of ICESat data to estimate forest height is complicated by the pulse broadening associated with large-footprint, waveform-sampling lidar. We combined ICESat waveforms and ancillary topography from the Shuttle Radar Topography Mission to estimate maximum forest height in three ecosystems; tropical broadleaf forests in Brazil, temperate broadleaf forests in Tennessee, and temperate needleleaf forests in Oregon. Final models for each site explained between 59% and 68% of variance in field-measured forest canopy height (RMSE between 4.85 and 12.66 m). In addition, ICESat-derived heights for the Brazilian plots were correlated with field-estimates of aboveground biomass (r(2) = 73%, RMSE = 58.3 Mgha(-1)). C1 Colorado State Univ, Dept Forest Sci, Ft Collins, CO 80523 USA. NASA, Goddard Space Flight Ctr, Planetary Geodynam Branch, Greenbelt, MD 20771 USA. Forest Serv, Int Inst Trop Forestry, USDA, San Juan, PR USA. Univ New Hampshire, Complex Syst Res Ctr, Durham, NH 03824 USA. Forest Serv, Forestry Sci Lab, Pacific NW Res Stn, USDA, Corvallis, OR 97331 USA. NASA, Goddard Space Flight Ctr, NVI Inc, Space Geodesy Branch, Greenbelt, MD 20771 USA. Inst Nacl Pesquisas Espaciais, BR-12227010 Sao Jose Dos Campos, Brazil. EMBRAPA Amazonia Oriental, BR-66095100 Belem, Para, Brazil. RP Lefsky, MA (reprint author), Colorado State Univ, Dept Forest Sci, Campus Delivery 1472, Ft Collins, CO 80523 USA. EM lefsky@fsl.orst.edu RI Lefsky, Michael/A-7224-2009; Keller, Michael/A-8976-2012; Espirito-Santo, Fernando/O-4371-2014; Harding, David/F-5913-2012 OI Keller, Michael/0000-0002-0253-3359; Espirito-Santo, Fernando/0000-0001-7497-3639; NR 14 TC 207 Z9 222 U1 12 U2 58 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 NOV 1 PY 2005 VL 32 IS 22 AR L22S02 DI 10.1029/2005GL023971 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 982LO UT WOS:000233160100001 ER PT J AU Klingelhofer, G DeGrave, E Morris, RV Alboom, A de Resende, VG De Souza, PA Rodionov, D Schroder, C Ming, DW Yen, A AF Klingelhoefer, G. DeGrave, E. Morris, R. V. Van Alboom, A. de Resende, V. G. De Souza, P. A., Jr. Rodionov, D. Schroeder, C. Ming, D. W. Yen, A. TI Mossbauer spectroscopy on Mars: goethite in the Columbia Hills at Gusev crater SO HYPERFINE INTERACTIONS LA English DT Article DE MIMOS II; weathering; Mars; goethite; hematite; field distribution; Gusev crater; Mars-Exploration-Rovers; mineralogy ID SPECTROMETER AB In January 2004 the USA space agency NASA landed two rovers on the surface of Mars, both carrying the Mainz Mossbauer spectrometer MIMOS II. The instrument on the Mars-Exploration-Rover (MER) Spirit analyzed soils and rocks on the plains and in the Columbia Hills of Gusev crater landing site on Mars. The surface material in the plains have an olivine basaltic signature [1, 5] suggesting physical rather than chemical weathering processes present in the plains. The Mossbauer signature for the Columbia Hills surface material is very different ranging from nearly unaltered material to highly altered material. Some of the rocks, in particular a rock named Clovis, contain a significant amount of the Fe oxyhydroxide goethite, alpha-FeOOH, which is mineralogical evidence for aqueous processes because it is formed only under aqueous conditions. In this paper we describe the analysis of these data using hyperfine field distributions (HFD) and discuss the results in comparison to terrestrial analogues. C1 Johannes Gutenberg Univ Mainz, Inst Inorgan & Analyt Chem, D-55128 Mainz, Germany. Univ Ghent, NUMAT Div, Dept Subatom & Radiat Phys, B-9000 Ghent, Belgium. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Univ Fed Ouro Preto, Dept Quim, BR-35400 Ouro Preto, MG, Brazil. CVRD, Rio De Janeiro, Brazil. CALTECH, Jet Prop Lab, Pasadena, CA USA. RP Klingelhofer, G (reprint author), Johannes Gutenberg Univ Mainz, Inst Inorgan & Analyt Chem, Staudinger Weg 9, D-55128 Mainz, Germany. EM klingel@mail.uni-mainz.de RI de Souza, Paulo/B-8961-2008; Schroder, Christian/B-3870-2009 OI de Souza, Paulo/0000-0002-0091-8925; Schroder, Christian/0000-0002-7935-6039 NR 7 TC 17 Z9 17 U1 0 U2 6 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0304-3843 J9 HYPERFINE INTERACT JI Hyperfine Interact. PD NOV PY 2005 VL 166 IS 1-4 BP 549 EP 554 DI 10.1007/s10751-006-9329-y PG 6 WC Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter; Physics, Nuclear SC Physics GA 118UX UT WOS:000242969500034 ER PT J AU Burr, DA Soare, RJ Tseung, JMWB Emery, JP AF Burr, DA Soare, RJ Tseung, JMWB Emery, JP TI Young (late Amazonian), near-surface, ground ice features near the equator, Athabasca Valles, Mars SO ICARUS LA English DT Article ID WESTERN-ARCTIC-COAST; LIQUID WATER; GLOBAL DISTRIBUTION; CERBERUS FOSSAE; RING STRUCTURES; SUBSURFACE ICE; PINGO GROWTH; FLOOD LAVAS; CANADA; ANTARCTICA AB A suite of four feature types in a similar to 20 km(2) area near 10 degrees N, 204'degrees W in Athabasca Valles is interpreted to have resulted from near-surface,around ice. These features include mounds, conical forms with rimmed summit depressions, flatter irregularly-shaped forms with raised rims, and polygonal terrain. Based on morphology, size, and analogy to terrestrial,round ice forms, these Athabascan features are interpreted as pingos, collapsing pingos, pingo scars. and thermal contraction polygons, respectively. Thermal Infrared Mapping Spectrometer (THEMIS) data and geological features in the area are consistent with a sedimentary Substrate underlying these features. These observations lead us to favor a ground ice interpretation, although we do not rule out volcanic and especially glaciofluvial hypotheses. The hypothesized ground ice that formed the mounds and rimmed features may have been emplaced via the deposition of Saturated sediment during flooding; an alternative scenario invokes magmatically cycled groundwater. The ground ice implicit in the hypothesized thermal contraction polygons may have derived either from this flooding/ground water, or from atmospheric water vapor. The lack of obvious flood modification of the Mounds and rimmed features indicates that they formed after the most recent flood inundated the area. Analogy with terrestrial pingos suggests that,round ice may be still extant within the positive relief Mounds. As the water that flooded down Athabasca Valles emerged via a volcanotectonic fissure from a deep aquifer, any extant pingo ice may contain evidence of a deep subsurface biosphere. (c) 2005 Elsevier Inc. All rights reserved. C1 SETI Inst, Mountain View, CA 94043 USA. US Geol Survey, Astrogeol Program, Flagstaff, AZ 86001 USA. Concordia Univ, Dept Geog, Montreal, PQ H3G 1M8, Canada. McGill Univ, Dept Geog, Montreal, PQ H3A 2K6, Canada. NASA, Ames Res Ctr, SETI Inst, Moffett Field, CA 94035 USA. RP Burr, DA (reprint author), SETI Inst, 515 N Whisman Dr, Mountain View, CA 94043 USA. EM dburr@pirl.lpl.arizona.edu NR 89 TC 58 Z9 59 U1 1 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 J9 ICARUS JI Icarus PD NOV 1 PY 2005 VL 178 IS 1 BP 56 EP 73 DI 10.1016/j.icarus.2005.04.012 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 977ZA UT WOS:000232840800006 ER PT J AU Alvarellos, JL Zahnle, KJ Dobrovolskis, AR Hamill, P AF Alvarellos, JL Zahnle, KJ Dobrovolskis, AR Hamill, P TI Fates of satellite ejecta in the Saturn system SO ICARUS LA English DT Article DE satellites of saturn; cratering; impact process; orbits ID IMAGING SCIENCE; CRATERING RATES; SOLAR-SYSTEM; FRAGMENTS; VELOCITY; VOYAGER-2; EVOLUTION; IMPACTS; ORBITS; COMETS AB We use conventional numerical integrations to assess the fates of impact ejecta, in the Saturn System. For specificity we consider impact ejecta launched from four giant craters on three satellites: Herschel on Mimas, Odysseus and Penelope on Tethys, and Tirawa on Rhea. Speeds, trajectories, and size of the ejecta are consistent with impact on a competent surface ("spalls") and into unconsolidated regolith. We do not include near-field effects, jetting, or effects peculiar to highly oblique impact. Ejecta are launched at velocities comparable to or exceeding the satellite's escape speed. Most ejecta are swept up by the Source moon on time-scales of a few to several decades, and produce craters no larger than 19 km in diameter, with typical craters in the rang of a few km. As much as 17% of ejecta reach satellites other than the source moon. our models,generate cratering patterns consistent with a planetocentric origin of most small impact craters on the saturnian icy moons, but the predicted craters tend to be smaller than putative Population II craters. We conclude that ejecta from the known giant craters in the saturnian system do not fully account for Population II craters. published by Elsevier Inc. C1 Loral, Space Syst, Palo Alto, CA 94303 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Univ Calif Santa Cruz, Univ Calif Observ, Lick Observ, Santa Cruz, CA 95064 USA. San Jose State Univ, Dept Phys, San Jose, CA 95192 USA. RP Alvarellos, JL (reprint author), Loral, Space Syst, 3825 Fabian Way,MS G-76, Palo Alto, CA 94303 USA. EM alvarellos.jose@ssd.loral.com NR 43 TC 19 Z9 19 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 NOV 1 PY 2005 VL 178 IS 1 BP 104 EP 123 DI 10.1016/j.icarus.2005.04.017 PG 20 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 977ZA UT WOS:000232840800010 ER PT J AU McKay, CP Smith, HD AF McKay, CP Smith, HD TI Possibilities for methanogenic life in liquid methane on the surface of Titan SO ICARUS LA English DT Article DE Titan; life; methanogens ID ATMOSPHERE; VOYAGER-1; AEROSOLS; OCEAN AB Photocheinically produced compounds on Titan, principally acetylene, ethane and organic solids. would release energy when consumed with atmospheric hydrogen. at levels of 334, 57. and 54 kJ mol(-1). respectively. Oil Earth methanogenic bacteria can Survive on this energy level. Here we speculate on the possibility of widespread methanogenic life in liquid methane on Titan. Hydrogen may be the best molecule to show the affects of such life because it does not condense at the tropopause and has no sources or sinks in the troposphere. If life is consuming atmospheric hydrogen it will have a measurable effect oil the hydrogen mixing ratio in the troposphere if the biological consumption is greater than 10(8) cm(-2) s(-1). Life could develop strategies to overcome the low solubility of organics in liquid methane and use catalysts to accelerate biochemical reactions despite the low temperature. The results of the recent Huygens probe could indicate the presence of such life by anomalous depictions of acetylene and ethane as well as hydrogen at the surface. (c) 2005 Elsevier Inc. All rights reserved. C1 NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. Int Space Univ, Masters Space Studies Program, F-67400 Strasbourg, France. NASA, Ames Res Ctr, SETI Inst, Moffett Field, CA 94035 USA. RP McKay, CP (reprint author), NASA, Ames Res Ctr, Div Space Sci, Mail Stop 245-3, Moffett Field, CA 94035 USA. EM cmckay@mail.arc.nasa.gov NR 18 TC 78 Z9 84 U1 5 U2 43 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 NOV 1 PY 2005 VL 178 IS 1 BP 274 EP 276 DI 10.1016/j.icarus.2005.05.018 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 977ZA UT WOS:000232840800023 ER PT J AU Scheeres, DJ Benner, LAM Ostro, SJ Rossi, A Marzari, F Washabaugh, P AF Scheeres, DJ Benner, LAM Ostro, SJ Rossi, A Marzari, F Washabaugh, P TI Abrupt alteration of Asteroid 2004 MN4's spin state during its 2029 Earth flyby SO ICARUS LA English DT Article DE asteroids; rotational dynamics; rotation; dynamics; radar ID GRAVITATIONAL INTERACTIONS AB We predict that when Asteroid 2004 MN4 passes 5.6 +/- 1.4 Earth radii from Earth's center oil April 13, 2029, terrestrial torques during the flyby will alter its,pill State in a dramatic manner that will be observable using groundbased telescopes. Although the asteroid will most likely not undergo catastrophic disruption. it may be subject to localized failure across its surface and interior, providing a unique opportunity to measure otherwise inaccessible mechanical properties of an asteroid. (c) 2005 Elsevier Inc. All rights reserved. C1 Univ Michigan, Dept Aerosp Engn, Ann Arbor, MI 48109 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. CNR, ISTI, I-56124 Pisa, Italy. Univ Padua, Dept Phys, I-35131 Padua, Italy. RP Univ Michigan, Dept Aerosp Engn, Ann Arbor, MI 48109 USA. EM scheeres@umich.edu RI Rossi, Alessandro/D-4408-2016 OI Rossi, Alessandro/0000-0001-9311-2869 NR 11 TC 21 Z9 21 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 EI 1090-2643 J9 ICARUS JI Icarus PD NOV 1 PY 2005 VL 178 IS 1 BP 281 EP 283 DI 10.1016/j.icarus.2005.06.002 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 977ZA UT WOS:000232840800025 ER PT J AU Jakosky, BM Mellon, MT Varnes, ES Feldman, WC Boynton, WV Haberle, RM AF Jakosky, BM Mellon, MT Varnes, ES Feldman, WC Boynton, WV Haberle, RM TI Mars low-latitude neutron distribution: Possible remnant near-surface water ice and a mechanism for its recent emplacement (vol 175, pg 58, 2005) SO ICARUS LA English DT Correction C1 Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80309 USA. Univ Colorado, Dept Geol Sci, Boulder, CO 80309 USA. Los Alamos Natl Lab, Los Alamos, NM 87544 USA. Univ Arizona, Dept Planetary Sci, Tucson, AZ 85721 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Jakosky, BM (reprint author), Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80309 USA. EM bruce.jakosky@lasp.colorado.edu RI Mellon, Michael/C-3456-2016 NR 1 TC 2 Z9 2 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 NOV 1 PY 2005 VL 178 IS 1 BP 291 EP 293 DI 10.1016/j.icarus.2005.07.002 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 977ZA UT WOS:000232840800027 ER PT J AU Schwartz, ZD Ponchak, GE AF Schwartz, ZD Ponchak, GE TI 1-GHz, 200 degrees C, SiC MESFET clapp oscillator SO IEEE MICROWAVE AND WIRELESS COMPONENTS LETTERS LA English DT Article DE high temperature; SiC; oscillator AB A SiC Clapp oscillator fabricated on an alumina substrate with chip capacitors and spiral inductors is designed for high-temperature operation at 1 GHz. The oscillator operated from 30 degrees C to 200 degrees C with an output power of 21.8 dBm at 1 GHz and 200 degrees C. The efficiency at 200 degrees C is 15%. The frequency variation over the temperature range is less than 0.5%. C1 NASA, Analex Corp, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Schwartz, ZD (reprint author), Aeroflex Inc, Powell, OH 43065 USA. EM george.ponchak@ieee.org NR 11 TC 14 Z9 14 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 NOV PY 2005 VL 15 IS 11 BP 730 EP 732 DI 10.1109/LMWC.2005.858995 PG 3 WC Engineering, Electrical & Electronic SC Engineering GA 983CH UT WOS:000233208200004 ER PT J AU Pogorzelski, RJ Chiha, FE AF Pogorzelski, RJ Chiha, FE TI A demonstration of the coupled oscillator based agile beam receiver concept SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION LA English DT Article DE mutual injection locking; phased array antennas; voltage controlled oscillator ID ARRAYS AB The Cao-York concept of using a linear array of mutually injection locked oscillators to provide local oscillator signals for an agile beam receiver is demonstrated using a 15 circuit array of L-band voltage controlled oscillators coupled to nearest neighbors. The concept involves mixing each 1.265 GHz local oscillator (1-o) signal with a corresponding 1.950 GHz signal received by an element in an antenna aperture and combining the resulting 685 MHz intermediate frequency (i-f) signals. A normally incident wave is simulated using a power divider to provide 15 equal in-phase signals to the r-f ports of the mixers and the i-f combining is accomplished using a similar power divider in reverse. The "antenna beam" is steered through this "normally incident wave" by antisymmetrically detuning the end oscillators of the array and a plot of the i-f combiner output represents the receive beam shape. Finally, this system is used to demonstrate the Kott sidelobe suppression technique. 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 pogo@jpl.nasa.gov NR 7 TC 5 Z9 6 U1 1 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 NOV PY 2005 VL 53 IS 11 BP 3584 EP 3588 DI 10.1109/TAP.2005.858835 PG 5 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 985BC UT WOS:000233350100021 ER PT J AU Tang, XD Tao, G Joshi, SM AF Tang, XD Tao, G Joshi, SM TI Virtual grouping based adaptive actuator failure compensation for MIMO nonlinear systems SO IEEE TRANSACTIONS ON AUTOMATIC CONTROL LA English DT Article DE actuator failure; adaptive control; backstepping; multiple-input-mutliple-output (MIMO) system ID FAULT-DIAGNOSIS AB A new control design technique called virtual grouping is presented to handle actuator redundancy and failures for multiple-input-mutliple-output (MIMO) systems, enlarging the set of compensable actuator failures. An adaptive compensation scheme is thus developed for a class of nonlinear MIMO systems to ensure closed-loop signal boundedness and asymptotic output tracking despite unknown actuator failures. Simulation results are given to show the effectiveness of the adaptive design. C1 Univ Virginia, Dept Elect & Comp Engn, Charlottesville, VA 22904 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Univ Virginia, Dept Elect & Comp Engn, Charlottesville, VA 22904 USA. EM xt3f@virginia.edu; gt9s@virginia.edu; s.m.joshi@larc.nasa.gov NR 14 TC 27 Z9 33 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0018-9286 EI 1558-2523 J9 IEEE T AUTOMAT CONTR JI IEEE Trans. Autom. Control PD NOV PY 2005 VL 50 IS 11 BP 1775 EP 1780 DI 10.1109/TAC.2005.858633 PG 6 WC Automation & Control Systems; Engineering, Electrical & Electronic SC Automation & Control Systems; Engineering GA 986IG UT WOS:000233442700011 ER PT J AU Jackson, TJ Bindlish, R Gasiewski, AJ Stankov, B Klein, M Njoku, EG Bosch, D Coleman, TL Laymon, CA Starks, P AF Jackson, TJ Bindlish, R Gasiewski, AJ Stankov, B Klein, M Njoku, EG Bosch, D Coleman, TL Laymon, CA Starks, P TI Polarimetric scanning radiometer C- and X-band microwave observations during SMEX03 SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article; Proceedings Paper CT IEEE International Geoscience and Remote Sensing Symposium CY SEP 20-24, 2004 CL Anchorage, AK SP IEEE, IEEE Geosci & Remote Sensing Soc, Univ Alaska Fairbanks, Geophys Inst, Univ Missouri Columbia, NASA, NOAA, USN, Off Naval Res, Ball Aerosp &Technol Corp, Natl Polar Orbiting Operat Environm Satellite Syst, Japan Aerosp Explorat Agcy, Raytheon, US Geol Survey, ITT Ind, IEEE Ocean Engn Soc, Int Union Radio Sci DE Advanced Microwave Scanning Radiometer (AMSR-E); passive microwave; soil moisture; validation ID SOIL-MOISTURE RETRIEVAL; AMSR-E; MISSION AB Soil Moisture Experiment 2003 (SMEX03) was the second in a series of field campaigns using the National Oceanic and Atmospheric Administration Polarimetric Scanning Radiometer (PSR/CX) designed to validate brightness temperature (TB) data and soil moisture retrieval algorithms for the Advanced Microwave Scanning Radiometer (AMSR-E) for the Earth Observing System on the Aqua satellite. Objectives related to the PSR/CX during SMEX03 included: calibration and validation of AMSR-E TB observations over different climate/vegetation regions of the U.S. [Alabama (AL), Georgia (GA), Oklahoma (OK)], identification of possible areas of radio-frequency interference (RFI), comparison of X-band observations from Tropical Rainfall Measurement Mission Microwave Imager (TMI), AMSR-E, and PSR/CX, and exploring the potential of soil moisture retrieval algorithms using C- and X-band imagery in diverse landscapes. In the current investigation, more than 100 flightlines of PSR/CX data were extensively processed to produce gridded TB products for the four study regions. Due to the lack of significant rainfall in OK, generally dry soil moisture conditions were observed. Observations obtained over AL include a wide range of soil moisture and vegetation conditions. Results from the AL site clearly showed a lack of sensitivity to rainfall/soil moisture under forest canopy cover. Quantitative comparisons made with the TMI validated that both the PSR/CX and AMSR-E X-band channels were well calibrated. Spectral analyses indicated that the PSR/CX observations at C-band also are reasonable. As expected, there were varying degrees of RFI in the AMSR-E C-band data for the study sites that will prevent further soil moisture analysis using these data. X-band comparisons of the PSR/CX high-resolution and AMSR-E and TMI low-resolution data indicated a linear scaling for the range of conditions studied in SMEX03. These results will form the basis for further soil moisture investigations. C1 USDA ARS, Hydrol & Remote Sensing Lab, Beltsville, MD 20705 USA. Sci Syst & Applicat Inc, Lanham, MD 20706 USA. Natl Ocean & Atmospher Adm, Environm Technol Lab, Boulder, CO 80305 USA. Jet Prop Lab, Pasadena, CA 91109 USA. USDA ARS, SE Watershed Res Ctr, Tifton, GA 31794 USA. Alabama A&M Univ, Hydrol Soil Climatol & Remote Sensing Res Ctr, Normal, AL 35762 USA. Global Hydrol & Climate Ctr, Huntsville, AL 35805 USA. USDA ARS, Grazinglands Res Lab, El Reno, OK 73036 USA. RP USDA ARS, Hydrol & Remote Sensing Lab, Beltsville, MD 20705 USA. EM tjackson@hydrolab.arsusda.gov NR 12 TC 52 Z9 52 U1 0 U2 7 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 NOV PY 2005 VL 43 IS 11 BP 2418 EP 2430 DI 10.1109/TGRS.2005.857625 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 979KU UT WOS:000232941700002 ER PT J AU Pham, H Kim, EJ England, AW AF Pham, H Kim, EJ England, AW TI An analytical calibration approach for microwave polarimetric radiometers SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article; Proceedings Paper CT IEEE International Geoscience and Remote Sensing Symposium CY SEP 20-24, 2004 CL Anchorage, AK SP IEEE, IEEE Geosci & Remote Sensing Soc, Univ Alaska Fairbanks, Geophys Inst, Univ Missouri Columbia, NASA, NOAA, USN, Off Naval Res, Ball Aerosp &Technol Corp, Natl Polar Orbiting Operat Environm Satellite Syst, Japan Aerosp Explorat Agcy, Raytheon, US Geol Survey, ITT Ind, IEEE Ocean Engn Soc, Int Union Radio Sci DE calibration; error analysis; microwave radiometry; polarimetry; remote sensing; soil measurements AB We present an analytical calibration approach for passive microwave polarimeters that is applicable where the instrument can be partitioned into distinct, functional radio-frequency blocks. The methodology is focused on polarimetric system characterization, not polarimetric measurements. It requires characterization of each major internal functional subsystem with a vector network analyzer to obtain a closed-form transfer function. The goals of this approach are to provide a transfer function describing the system in its entirety and to isolate the contribution of each subsystem to the uncertainty in the final modified Stokes parameters. Notably, the approach does not assume ideal polarization isolation in the radiometer system. A significant benefit of this approach is that the cascaded transfer functions serve as a realistic instrument simulator revealing where improvements in component performance would have greatest benefit for system performance over the dynamic range of the instrument. This systems-focused approach is applied to the National Aeronautics and Space Admnistration Goddard Space Flight Center polarimetric Airborne C-band Microwave Radiometer (ACMR), whose architecture allows the necessary subsystem partitioning. The characteristics of each subsystem were extensively measured, converted to a transfer function, and imported into the overall closed-form system model. Inversion of the system model and error analysis inherent to this calibration approach are illustrated by a full Stokes parameter retrieval for a senescent cornfield. C1 Univ Michigan, Microwave Geophys Grp, Ann Arbor, MI 48109 USA. NASA, Goddard Space Flight Ctr, Microwave Sensors Branch, Greenbelt, MD 20771 USA. RP Pham, H (reprint author), Univ Michigan, Microwave Geophys Grp, Ann Arbor, MI 48109 USA. EM hpham@umich.edu; ed.kim@nasa.gov; england@umich.edu NR 23 TC 4 Z9 4 U1 0 U2 4 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 NOV PY 2005 VL 43 IS 11 BP 2443 EP 2451 DI 10.1109/TGRS.2005.857323 PG 9 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 979KU UT WOS:000232941700004 ER PT J AU Ichoku, C Kaufman, YJ AF Ichoku, C Kaufman, YJ TI A method to derive smoke emission rates from MODIS fire radiative energy measurements SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE aerosol; biomass burning; fire radiative energy (FRE); Moderate Resolution Imaging Spectroradiometer (MODIS); particulate matter; smoke emission ID SOUTHERN AFRICA; SCAR-B; SATELLITE; ALGORITHM; PRODUCTS; VALIDATION; ATMOSPHERE; AEROSOLS; AMERICA; TROPICS AB Present methods of emissions estimation from satellite data often use fire pixel counts, even though fire strengths and smoke emission rates can differ by some orders of magnitude between pixels. Moderate Resolution Imaging Spectroradiometer (MODIS) measurements of fire radiative energy (FRE) release rates R-fre range from less than 10 to more than 1700 MW per pixel at I-km resolution. To account for the effect of such a wide range of fire strengths/sizes on smoke emission rates, we have developed direct linear relationships between the MODIS-measured R-fre and smoke aerosol emission rates R-sa (in kilograms per second), derived by analyzing MODIS measurements of aerosol spatial distribution around the fires with National Center for Environmental Prediction/National Center for Atmospheric Research wind fields. We applied the technique to several regions around the world and derived a FRE-based smoke emission coefficient, C-e (in kilograms per megajoule), which can be simply multiplied by R-fre to calculate R-sa. This new coefficient C-e is an excellent remote sensing parameter expressing the emission strength of different ecosystems and regions. Analysis of all 2002 MODIS data from Terra and Aqua satellites yielded C-e values of 0.02-0.06 kg/MJ for boreal regions, 0.044.08 kg/MJ for both tropical forests and savanna regions, and 0.08-0.1 kg/MJ for Western Russian regions. These results are probably overestimated by about 50% because of uncertainties in some of the data, parameters, and assumptions; involved in the computations. This 50% overestimation is comparable to uncertainties in traditional emission factors. However, our satellite method shows great promise for accuracy improvement, as better knowledge is gained about the sources of the uncertainties. C1 Sci Syst & Applicat Inc, Lanham, MD 20706 USA. NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. RP Sci Syst & Applicat Inc, Lanham, MD 20706 USA. EM ichoku@climate.gsfc.nasa.gov; yoram.j.kaufman@nasa.gov RI Ichoku, Charles/E-1857-2012 OI Ichoku, Charles/0000-0003-3244-4549 NR 46 TC 115 Z9 119 U1 2 U2 28 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 NOV PY 2005 VL 43 IS 11 BP 2636 EP 2649 DI 10.1109/TGRS.2005.857328 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 979KU UT WOS:000232941700023 ER PT J AU Li, CC Lau, AKH Mao, JT Chu, DA AF Li, CC Lau, AKH Mao, JT Chu, DA TI Retrieval, validation, and application of the 1-km aerosol optical depth from MODIS measurements over Hong Kong SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE aerosols; air pollution; remote sensing ID AIR-QUALITY; TROPOSPHERIC AEROSOL; PRODUCTS AB The Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol retrieval algorithm was developed to derive aerosol properties at a global scale, suitable for climate studies. Under favorable conditions (clear sky and over dark surfaces), the standard 10 x 10 km MODIS aerosol products are also useful on regional scales to monitor aerosol distributions and transports. However, the 10-km resolution is insufficient to depict aerosol variation on local or urban scales, due to inherent aerosol variability as well as complex surface terrain. In this study, we have modified the MODIS algorithm to retrieve aerosol optical depth (AOD) at 1-km resolution over Hong Kong, a city of just over 1000 km(2) with very complex surface features. Accompanied by the increased spatial resolution are new aerosol models derived with single-scattering albedo (SSA) around 0.91-0.94 to accommodate higher aerosol absorption encountered in Hong Kong than that was presumed for MODIS standard products (SSA similar to 0.97) over the region. The derived AOD data are compared to handheld Microtops II sunphotometer observations at the Hong Kong University of Science and Technology and other locations across Hong Kong. Retrieval errors within 15% to 20% of sunphotometer measurements are found. Moreover, when compared with the standard 10-km AOD products, the I-km AOD data are much better correlated with PM10 measurements across Hong Kong, suggesting that the new 1-km AOD data can be used to better characterize the particulate matter distribution for cities like Hong Kong than the MODIS standard products. C1 Peking Univ, Dept Atmospher Sci, Sch Phys, Beijing 100871, Peoples R China. Hong Kong Univ Sci & Technol, Ctr Coastal & Atmospher Res, Hong Kong, Hong Kong, Peoples R China. Univ Maryland Baltimore Cty, Joint Ctr Earth Sci & Technol, Baltimore, MD 21228 USA. NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. RP Li, CC (reprint author), Peking Univ, Dept Atmospher Sci, Sch Phys, Beijing 100871, Peoples R China. EM ccli@pku.edu.cn; alau@ust.hk; mjt@pku.edu.cn; achu@climate.gsfc.nasa.gov RI LI, Chengcai/B-4654-2012; Lau, Alexis/D-7914-2013 OI LI, Chengcai/0000-0001-8860-1916; Lau, Alexis/0000-0003-3802-828X NR 26 TC 95 Z9 112 U1 4 U2 27 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 NOV PY 2005 VL 43 IS 11 BP 2650 EP 2658 DI 10.1109/TGRS.2005.856627 PG 9 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 979KU UT WOS:000232941700024 ER PT J AU Rubaai, A Ofoli, AR Cobbinah, D Kankam, MD AF Rubaai, A Ofoli, AR Cobbinah, D Kankam, MD TI Two-layer supervisory controller-based thyristor-controlled braking resistor for transient stability crisis SO IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS LA English DT Article; Proceedings Paper CT 39th Annual Meeting of the IEEE-Industry-Applications-Society CY OCT 03-07, 2004 CL Seattle, WA SP IEEE Ind Applicat Soc DE braking resistor (BR); firing angle; hierarchical structure; optimal control; thyristor switch; transient stability crisis ID MULTIMACHINE POWER-SYSTEM; FACTS DEVICES; FUZZY CONTROLLER; SERIES CAPACITOR; DESIGN AB In this paper, a supervisory two-layer control structure is synthesized with network elements as control means for thyristor-controlled braking resistor (BR) of multimachine power system operating in transient emergency state. This creates a multiple local feedback controller that can be realistically implemented using only local measurements and whose performance is consistent with respect to changes in network configuration, loading, and power transfer conditions. Following a major disturbance, the rotor angle and rotor speed of each generator unit are determined and the firing angle of the thyristor switch associated with the BR is computed by the local controllers. By controlling the firing angle of the thyristor, the BR controls the accelerating power in each generator and, thus, enhances the stability margins and damping oscillations. Since the local controllers rely only on measurements particular to their own subsystem, interconnection effects and the nonlinearities introduced by them are accounted for by the supervisory layer. The two-layer controller was tested on the IEEE Western States Coordinating Council (WSCC) test system. Results show that the controller is capable of bringing the system under control when starting with inherently unstable conditions, even when the severity of the disturbances is increased. C1 Howard Univ, Dept Elect & Comp Engn, Washington, DC 20059 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Rubaai, A (reprint author), Howard Univ, Dept Elect & Comp Engn, Washington, DC 20059 USA. EM arubaai@howard.edu; mark.d.kankam@grc.nasa.gov NR 21 TC 3 Z9 5 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0093-9994 J9 IEEE T IND APPL JI IEEE Trans. Ind. Appl. PD NOV-DEC PY 2005 VL 41 IS 6 BP 1539 EP 1547 DI 10.1109/TIA.2005.0857465 PG 9 WC Engineering, Multidisciplinary; Engineering, Electrical & Electronic SC Engineering GA 986XX UT WOS:000233484100019 ER PT J AU Nayfeh, MH Rao, S Nayfeh, OM Smith, A Therrien, J AF Nayfeh, MH Rao, S Nayfeh, OM Smith, A Therrien, J TI UV photodetectors with thin-film Si nanoparticle active medium SO IEEE TRANSACTIONS ON NANOTECHNOLOGY LA English DT Article DE nanotechnology; photoconducting devices; photoconductivity; photodetector; photodiode; semiconductor devices; silicon; thin films ID ULTRASMALL SILICON NANOPARTICLES; SURFACE-STATES; LIGHT; NANOCRYSTALLITES AB We constructed ultraviolet (UV) photodetectors using thin films of silicon nanoparticles as active media. The Si nanoparticle films are electrodeposited, at room temperature on Si p-type substrates. Uniform silicon nanoparticles of 1-nm diameter are dispersed from Si wafers using electrochemical etching. The nanoparticles are ultrabright under UV excitation, with nanosecond luminescence time characteristics. Current-voltage (I-V) characteristics indicate a photoconductor in series with a diode-like junction with a large enhancement in the forward current under UV illumination. Our results point to a sensitive UV detector with good visible blindness where the particle films effectively constitutes a wide-bandgap material. C1 Univ Illinois, Dept Phys, Urbana, IL 61801 USA. MIT, Dept Elect Engn, Cambridge, MA 02139 USA. Purdue Univ, NASA, Inst Nanoelect & Comp Discovery Pk, W Lafayette, IN 47907 USA. RP Nayfeh, MH (reprint author), Univ Illinois, Dept Phys, Urbana, IL 61801 USA. EM m-nayfeh@uiuc.edu NR 27 TC 22 Z9 23 U1 3 U2 22 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 1536-125X J9 IEEE T NANOTECHNOL JI IEEE Trans. Nanotechnol. PD NOV PY 2005 VL 4 IS 6 BP 660 EP 668 DI 10.1109/TNANO.2005.858606 PG 9 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Science & Technology - Other Topics; Materials Science; Physics GA 984XQ UT WOS:000233341100003 ER PT J AU Waters, KR Johnston, PH AF Waters, KR Johnston, PH TI Tomographic imaging of an ultrasonic field in a plane by use of a linear array: Theory and experiment SO IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL LA English DT Article AB Quantitative ultrasonic characterization of inhomogeneous and anisotropic materials is often difficult due to undesired phenomena such as beam steering and phase aberration of the insonifying field. We introduce a method based on tomographic reconstruction techniques for the visualization of an ultrasonic field using a linear array rotated in a plane. Tomographic reconstruction of the ultrasonic field is made possible through the phase-sensitive nature of the tall, narrow piezoelectric elements of a linear array that act as parallel line integrators of the pressure field. We validate the proposed imaging method through numerical simulations of propagated ultrasonic fields based upon the angular spectrum decomposition technique. We then demonstrate the technique with experimental measurements of two textile composites and a reference water path. We reconstruct images of the real and imaginary parts of a transmitted 2 MHz ultrasonic field that are then combined to reconstruct images of the power and unwrapped phase. We also construct images of the attenuation and phase shift for several regions of the composites. Our results demonstrate that tomographic imaging of an ultrasonic field in a plane using a rotated linear array can potentially improve ultrasonic characterization of complex materials. C1 Natl Inst Stand & Technol, Div Mat Reliabil, Boulder, CO 80305 USA. NASA, Langley Res Ctr, Nondestruct Evaluat Sci Branch, Hampton, VA 23681 USA. RP Waters, KR (reprint author), Volcano Corp, Cleveland, OH 44195 USA. EM kwaters@volcanocorp.com NR 14 TC 1 Z9 1 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0885-3010 J9 IEEE T ULTRASON FERR JI IEEE Trans. Ultrason. Ferroelectr. Freq. Control PD NOV PY 2005 VL 52 IS 11 BP 2065 EP 2074 DI 10.1109/TUFFC.2005.1561676 PG 10 WC Acoustics; Engineering, Electrical & Electronic SC Acoustics; Engineering GA 988SJ UT WOS:000233620700021 PM 16422419 ER PT J AU Zhuravleva, TB Marshak, AL AF Zhuravleva, TB Marshak, AL TI On the validation of the Poisson model of broken clouds SO IZVESTIYA ATMOSPHERIC AND OCEANIC PHYSICS LA English DT Article ID STOCHASTIC RADIATIVE-TRANSFER; BOUNDARY-LAYER CLOUDS; INDEPENDENT PIXEL APPROXIMATION; LIQUID WATER DISTRIBUTIONS; AVERAGED SOLAR FLUXES; MARINE STRATOCUMULUS; SCALE-INVARIANCE; CUMULUS CLOUDS; PART I; FIELDS AB In this study, the validation of a stochastic model of broken clouds based on the Poisson point fluxes is considered. As a prototype of real cloud fields, realizations obtained by the fractionally integrated cascade model are used. To consider variations in the cloud optical thickness (tau) in the Poisson model, additional averaging of radiative characteristics in accordance with the probability density (f(tau)) is proposed. The effective value of the aspect ratio gamma, which is the most important input parameter of the Poisson model, is chosen from the condition that the mean nonscattered fluxes calculated with the Poisson and cascade models areconsistent. It is shown that, for the conditions of low or moderate cloud fractions (N < 0.7) and of moderate light absorption by water droplets (the single scattering albedo (omega >= 0.95), this approach allows a more accurate calculation of the area-average diffuse-solar-radiation fluxes than the independent pixel approximation and than th,-, model of C1 Russian Acad Sci, Inst Atmospher Opt, Siberian Div, Tomsk 634055, Russia. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Zhuravleva, TB (reprint author), Russian Acad Sci, Inst Atmospher Opt, Siberian Div, Pr Akademicheskii 1, Tomsk 634055, Russia. EM ztb@iao.ru; Alexander.Marshak@nasa.gov RI Marshak, Alexander/D-5671-2012 NR 53 TC 5 Z9 5 U1 0 U2 1 PU INTERPERIODICA PI BIRMINGHAM PA PO BOX 1831, BIRMINGHAM, AL 35201-1831 USA SN 0001-4338 J9 IZV ATMOS OCEAN PHY+ JI Izv. Atmos. Ocean. Phys. PD NOV-DEC PY 2005 VL 41 IS 6 BP 713 EP 725 PG 13 WC Meteorology & Atmospheric Sciences; Oceanography SC Meteorology & Atmospheric Sciences; Oceanography GA 992WN UT WOS:000233914800005 ER PT J AU Matloff, GL Johnson, L AF Matloff, GL Johnson, L TI Applications of the electrodynamic tether to interstellar travel SO JBIS-JOURNAL OF THE BRITISH INTERPLANETARY SOCIETY LA English DT Article DE interstellar travel; tethers; world ships; ramscoops; thrustless turning; on-board power sources ID PROBES AB After considering relevant properties of the local interstellar medium and defining a sample interstellar mission, this paper considers possible interstellar applications of the electrodynamic tether, or EDT. These include use of the EDT to provide on-board power and affect trajectory modifications and direct application of the EDT to starship acceleration. It is demonstrated that comparatively modest EDTs can provide substantial quantities of on-board power, if combined with a large-area electron-collection device such as the Cassenti toroidal-field ramscoop. More substantial tethers can be used to accomplish large-radius thrustless turns. Direct application of the EDT to starship acceleration is apparently infeasible. C1 CUNY, New York City Coll Technol, Dept Phys & Biol Sci, Brooklyn, NY 11201 USA. Gray Res Inc, Huntsville, AL 35806 USA. NASA, George C Marshall Space Flight Ctr, In Space Prop Technol Project, Huntsville, AL 35812 USA. RP Matloff, GL (reprint author), CUNY, New York City Coll Technol, Dept Phys & Biol Sci, 300 Jay St, Brooklyn, NY 11201 USA. EM gregmat@hotmail.com; C.Les.Johnson@nasa.gov NR 23 TC 2 Z9 2 U1 1 U2 1 PU BRITISH INTERPLANETARY SOC PI LONDON PA 27-29 S LAMBETH RD, LONDON SW8 1SZ, ENGLAND SN 0007-084X J9 JBIS-J BRIT INTERPLA JI JBIS-J. Br. Interplanet. Soc. PD NOV-DEC PY 2005 VL 58 IS 11-12 BP 398 EP 402 PG 5 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary SC Engineering; Astronomy & Astrophysics; Geology GA 977RG UT WOS:000232820300007 ER PT J AU Kaya, N Iwashita, M Nakasuka, S Summerer, L Mankins, J AF Kaya, N Iwashita, M Nakasuka, S Summerer, L Mankins, J TI Crawling robots on large web in rocket experiment on Furoshiki deployment SO JBIS-JOURNAL OF THE BRITISH INTERPLANETARY SOCIETY LA English DT Article DE Furoshiki deployment; space large structure; Solar Power Satellite; microwave power transmission; retrodirective antenna AB It is one of the most important and critical issues to develop a technology to construct space huge transmitting antenna such as the Solar Power Satellite. The huge antenna have many useful applications in space, for example, telecommunication antennas for cellular phones, radars for remote sensing, navigation and observation, and so on. We are proposing to apply the Furoshiki satellite with robots to construct the huge structures. After a large web is deployed using the Furoshiki satellite in the same size of the huge antenna, all of the antenna elements crawl on the web with their own legs toward their allocated locations in order to realize a huge antenna. The micro-gravity experiment is planned using a sounding rocket of ISAS in order to demonstrate the feasibility of the deployment of the large web and the phased array performance. Three daughter satellites are being separated from the mother satellite with weak springs, and the daughter satellites deploy the Furoshiki web to a triangular shape at the size of about 20-40m. The dynamics of the daughter satellites and the web is observed by several cameras installed on the mother and daughter satellites during the deployment, while the performance of the phased array antenna using the retrodirective method will simultaneously be measured at the ground station. Finally two micro robots crawl from the mother satellite to the certain points on the web to demonstrate one promising way to construct R-F transmitter panels. The robots are internationally being developed by NASA, ESTEC and Kobe University. There are many various ideas for the robots to crawl on the web in the micro-gravity. Each organization is independently developing a different type of the robots. Kobe University is trying to develop wheels to run on the web by pinching the strings of the web. It can successfully run on the web, though the issue is found to tangle the strings. C1 Kobe Univ, Dept Syst & Comp Engn, Kobe, Hyogo 6578501, Japan. Univ Tokyo, Dept Aeronaut & Astronaut, Tokyo 1138656, Japan. ESA, Estec, Adv Concepts Team, SER A, NL-2201 AZ Noordwijk, Netherlands. NASA Headquarters, Washington, DC 20546 USA. RP Kaya, N (reprint author), Kobe Univ, Dept Syst & Comp Engn, Kobe, Hyogo 6578501, Japan. EM kaya@kobe-u.ac.jp; nakasuka@space.t.u-tokyo.ac.jp; Leopold.Summerer@esa.int; jmankins@hq.nasa.gov OI Summerer, Leopold/0000-0001-7742-5216 NR 4 TC 2 Z9 2 U1 1 U2 1 PU BRITISH INTERPLANETARY SOC PI LONDON PA 27-29 S LAMBETH RD, LONDON SW8 1SZ, ENGLAND SN 0007-084X J9 JBIS-J BRIT INTERPLA JI JBIS-J. Br. Interplanet. Soc. PD NOV-DEC PY 2005 VL 58 IS 11-12 BP 403 EP 406 PG 4 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary SC Engineering; Astronomy & Astrophysics; Geology GA 977RG UT WOS:000232820300008 ER PT J AU Owens, LR Wahls, RA Rivers, SM AF Owens, LR Wahls, RA Rivers, SM TI Off-design Reynolds number effects for a supersonic transport SO JOURNAL OF AIRCRAFT LA English DT Article; Proceedings Paper CT AIAA 39th Aerospace Sciences Meeting and Exhibits CY JAN 08-11, 2001 CL RENO, NV SP Amer Inst Aeronaut & Astronaut AB A high-Reynolds-number wind-tunnel investigation was conducted to assess Reynolds-number effects on the aerodynamic performance characteristics of a realistic, second-generation, supersonic transport concept. The tests included longitudinal studies at transonic and low-speed, high-lift conditions across a range of chord Reynolds numbers (8 x 106 to 120 x 106). Results presented focus on Reynolds-number and static aeroelastic sensitivities at Mach 0.30 and 0.90 for a configuration without a tail. Static aeroclastic effects, which mask Reynolds-number effects, were observed. Reynolds-number effects were generally small, and the drag data followed established trends of skin friction as a function of Reynolds number. Wing boundary layers thinned as Reynolds number increased producing a more nose-down pitching moment because of the increased effective wing camber. This study extends the existing Reynolds-number database for supersonic transports operating at off-design conditions. C1 NASA, Langley Res Ctr, Flow Phys & Control Branch, Hampton, VA 23681 USA. NASA, Langley Res Ctr, Configurat Aerodynam Branch, Hampton, VA 23681 USA. RP Owens, LR (reprint author), NASA, Langley Res Ctr, Flow Phys & Control Branch, Hampton, VA 23681 USA. NR 27 TC 4 Z9 5 U1 0 U2 2 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 NOV-DEC PY 2005 VL 42 IS 6 BP 1427 EP 1441 DI 10.2514/1.10433 PG 15 WC Engineering, Aerospace SC Engineering GA 991WV UT WOS:000233846200007 ER PT J AU Bhargava, C Loth, E Potapczuk, M AF Bhargava, C Loth, E Potapczuk, M TI Numerical simulation of icing clouds in the NASA Glenn Icing Research Tunnel SO JOURNAL OF AIRCRAFT LA English DT Article; Proceedings Paper CT AIAA 42nd Aerospace Sciences Meeting and Exhibit CY JAN 05-08, 2004 CL Reno, NV SP Amer Inst Aeronaut & Astronaut AB The objective of this study was to develop and employ a numerical simulation strategy for predicting the liquid water content (LWC) at the test-section plane of the NASA Glenn Icing Research Tunnel (IRT) as well as to characterize the icing cloud uniformity as a function of tunnel speed, droplet size, etc. The droplets were injected with a polydisperse distribution and based on previous computational airflow results, which included the spray-bar wakes, the air jets, and the heat-exchanger flow. To simulate the effects of turbulent diffusion behavior of water droplets in the IRT, a continuous-random-walk methodology was employed, which corrects for nonhomogeneous turbulence. To first understand the cloud dynamics emanating from isolated nozzles, experiments and simulations were conducted with only four injectors spraying in the IRT. The simulations showed good representation of the width and position (though not necessarily the shape) of the individual spray clouds at the test-section plane. Next, droplets issued by the baseline group of spray nozzles were simulated in order to determine the test-section LWC distributions which in turn were used to compare with experiments. The simulations indicated the importance of including turbulent diffusion, and that increased tunnel speed and droplet size tended to reduce overall uniformity, which was generally consistent with experimental results. C1 NASA, John H Glenn Res Ctr, Cleveland, OH 44135 USA. Univ Illinois, Urbana, IL 61801 USA. RP Bhargava, C (reprint author), Epic Syst Corp, Madison, WI USA. EM loth@uiuc.edu RI Loth, Eric/C-5805-2008 NR 16 TC 0 Z9 1 U1 0 U2 2 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 NOV-DEC PY 2005 VL 42 IS 6 BP 1442 EP 1451 DI 10.2514/1.11856 PG 10 WC Engineering, Aerospace SC Engineering GA 991WV UT WOS:000233846200008 ER PT J AU Silva, WA Piatak, DJ Scott, RC AF Silva, WA Piatak, DJ Scott, RC TI Identification of experimental unsteady aerodynamic impulse responses 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 AB The identification of experimental unsteady aerodynamic impulse responses using the Oscillating Turntable (OTT) at NASA Langley's Transonic Dynamics Tunnel is described. Results are presented for two configurations: a rigid semispan model and a rectangular wing with a supercritical airfoil section. Both models were used to acquire unsteady pressure data caused by pitching oscillations on the OTT. A deconvolution scheme involving a step input in pitch and the resultant step response in pressure, for several pressure transducers, is used to identify the pressure impulse responses. The identified impulse responses are then used to predict the pressure response caused by pitching oscillations at several frequencies. Comparisons. with the experimental data are presented. C1 NASA, Langley Res Ctr, Aeroelast Branch, Hampton, VA 23681 USA. RP Silva, WA (reprint author), NASA, Langley Res Ctr, Aeroelast Branch, Hampton, VA 23681 USA. NR 14 TC 2 Z9 2 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 NOV-DEC PY 2005 VL 42 IS 6 BP 1548 EP 1552 DI 10.2514/1.13151 PG 5 WC Engineering, Aerospace SC Engineering GA 991WV UT WOS:000233846200021 ER PT J AU Baldelli, DH Lind, RC Brenner, M AF Baldelli, DH Lind, RC Brenner, M TI Robust aeroelastic match-point solutions using describing function method SO JOURNAL OF AIRCRAFT LA English DT Article ID CONTROL SURFACE; BEHAVIOR; AIRFOIL AB A general nonlinear feedback framework to compute robust match-point solutions for aeroelastic/aeroservoelastic systems including uncertain and nonlinear operators is presented. Augmentation of the current match-point solution approach is sought using the mu method with nonlinear memoryless operators. An aeroelastic/acroservoelastic model is built by proper interconnection of several linear fractional transformations, so that aerodynamic and structural nonlinear effects can be incorporated into a robust analysis setup. The describing function technique is used to determine the stability boundary of the nonlinear feedback system, so that limit-cycle oscillations (LCO) can be predicted and the boundary stability behavior characterized. The resulting quasilinear model allows the computation of robust stability margins that reflects both flutter and LCO instabilities. A typical section model with control surface freeplay and uncertain structural stiffness parameters is used to demonstrate the proposed aeroelastic/aeroservoelastic modeling framework. In general, good agreement was obtained with published numerical and experimental wind-tunnel test results. Comments are provided concerning possible limitations of the proposed modeling methodology. C1 ZONA Technol Inc, Scottsdale, AZ 85251 USA. Univ Florida, Dept Mech & Aerosp Engn, Gainesville, FL 32611 USA. NASA, Dryden Flight Res Ctr, Aerostruct Branch, Edwards AFB, CA 93523 USA. RP Baldelli, DH (reprint author), ZONA Technol Inc, Scottsdale, AZ 85251 USA. NR 26 TC 5 Z9 5 U1 0 U2 2 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 NOV-DEC PY 2005 VL 42 IS 6 BP 1597 EP 1605 PG 9 WC Engineering, Aerospace SC Engineering GA 991WV UT WOS:000233846200026 ER PT J AU Anyamba, A Tucker, CJ AF Anyamba, A Tucker, CJ TI Analysis of Sahelian vegetation dynamics using NOAA-AVHRR NDVI data from 1981-2003 SO JOURNAL OF ARID ENVIRONMENTS LA English DT Article; Proceedings Paper CT Workshop on Changes in the Sahel CY OCT 14-16, 2003 CL Nairobi, KENYA SP Int Ctr Remote Sensing Environm DE NOAA-AVHRR; NDVI time series; Sahel; drought ID NINO SOUTHERN OSCILLATION; SUB-SAHARAN RAINFALL; EL-NINO; SATELLITE DATA; AFRICAN SAHEL; INDEX; VARIABILITY; DROUGHT; PATTERNS; TRENDS AB Remotely sensed measurements from NOAA-AVHRR expressed as normalized difference vegetation index (NDVI) have generated a 23-year time series appropriate for long-term studies of Sahel region. The close coupling between Sahelian rainfall and the growth of vegetation has made it possible to utilize NDVI data as proxy for the land surface response to precipitation variability. Examination of this time series reveals two periods; (a) 1982-1993 marked by below average NDVI and persistence of drought with a signature large-scale drought during the 1982-1985 period; and (b) 1994-2003, marked by a trend towards 'wetter' conditions with region-wide above normal NDVI conditions with maxima in 1994 and 1999. These patterns agree with recent region-wide trends in Sahel rainfall. However taken in the context of long-term Sahelian climate history, these conditions are still far below the wetter conditions that prevailed in the region from 1930 to 1965. These trend patterns can therefore only be considered to be a gradual recovery from extreme drought conditions that peaked during the 1983-1985 period. Systematic studies of changes on the landscape using high spatial resolution satellite data sets such as those from LANDSAT, SPOT and MODIS will provide a detailed spatial quantification and description of the recovery patterns at local scale. (c) 2005 Elsevier Ltd. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Greenbelt, MD 20771 USA. Univ Maryland Baltimore Cty, Goddard Earth Sci Technol Ctr, Baltimore, MD 21228 USA. RP Anyamba, A (reprint author), NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Code 614-4, Greenbelt, MD 20771 USA. EM assaf@ltpmail.gsfc.nasa.gov NR 59 TC 260 Z9 308 U1 11 U2 74 PU ACADEMIC PRESS LTD ELSEVIER SCIENCE LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0140-1963 J9 J ARID ENVIRON JI J. Arid. Environ. PD NOV PY 2005 VL 63 IS 3 BP 596 EP 614 DI 10.1016/j.jaridenv.2005.03.007 PG 19 WC Ecology; Environmental Sciences SC Environmental Sciences & Ecology GA 963XU UT WOS:000231840600006 ER PT J AU Tanelli, S Im, E Kobayashi, S AF Tanelli, S Im, E Kobayashi, S TI Spaceborne Doppler radar measurements of rainfall: Correction of errors induced by pointing uncertainties SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID VELOCITY-MEASUREMENTS; SEA-SURFACE; SPACECRAFT; PERFORMANCE; MISSION; SYSTEM AB In this paper a sea surface radar echo spectral analysis technique to correct for the rainfall velocity error caused by radar-pointing uncertainty is presented. The correction procedure is quite straightforward when the radar is observing a homogeneous rainfall field. When nonuniform beam filling (NUBF) occurs and attenuating frequencies are used, however, additional steps are necessary in order to correctly estimate the antenna-pointing direction. This new technique relies on the application of the combined frequency-time (CFT) algorithm to correct for uneven attenuation effects on the observed sea surface Doppler spectrum. The performance of this correction technique was evaluated by a Monte Carlo simulation of the Doppler precipitation radar backscatter from high-resolution 3D rain fields (either generated by a cloud resolving numerical model or retrieved from airborne radar measurements). The results show that the antenna-pointing-induced error can, indeed, be reduced by the proposed technique in order to achieve 1 m s(-1) accuracy on rainfall vertical velocity estimates. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Florence, Dipartimento Elettron & Telecomun, I-50121 Florence, Italy. RP Tanelli, S (reprint author), CALTECH, Jet Prop Lab, Mail Stop 300-243,4800 Oak Ridge Dr, Pasadena, CA 91109 USA. EM simone.tanelli@jpl.nasa.gov NR 18 TC 14 Z9 14 U1 0 U2 0 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 NOV PY 2005 VL 22 IS 11 BP 1676 EP 1690 DI 10.1175/JTECH1797.1 PG 15 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA 993YB UT WOS:000233993900004 ER PT J AU Lau, KM Wu, HT Sud, YC Walker, GK AF Lau, KM Wu, HT Sud, YC Walker, GK TI Effects of cloud microphysics on tropical atmospheric hydrologic processes and intraseasonal variability SO JOURNAL OF CLIMATE LA English DT Article ID MADDEN-JULIAN OSCILLATION; SCHUBERT SCHEME MCRAS; WESTERN PACIFIC; CONVECTION; PRECIPITATION; MODEL; PARAMETERIZATION; PROPAGATION; PREDICTION; RADIATION AB The sensitivity of tropical atmospheric hydrologic processes to cloud microphysics is investigated using the NASA Goddard Earth Observing System ( GEOS) general circulation model ( GCM). Results show that a faster autoconversion rate leads to ( a) enhanced deep convection in the climatological convective zones anchored to tropical land regions; ( b) more warm rain, but less cloud over oceanic regions; and ( c) an increased convective-to-stratiform rain ratio over the entire Tropics. Fewer clouds enhance longwave cooling and reduce shortwave heating in the upper troposphere, while more warm rain produces more condensation heating in the lower troposphere. This vertical differential heating destabilizes the tropical atmosphere, producing a positive feedback resulting in more rain and an enhanced atmospheric water cycle over the Tropics. The feedback is maintained via secondary circulations between convective tower and anvil regions ( cold rain), and adjacent middle-to-low cloud ( warm rain) regions. The lower cell is capped by horizontal divergence and maximum cloud detrainment near the freezing-melting ( 0 degrees C) level, with rising motion ( relative to the vertical mean) in the warm rain region connected to sinking motion in the cold rain region. The upper cell is found above the 0 degrees C level, with induced subsidence in the warm rain and dry regions, coupled to forced ascent in the deep convection region. C1 NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. RP Lau, KM (reprint author), NASA, Goddard Space Flight Ctr, Atmospheres Lab, Code 613, Greenbelt, MD 20771 USA. EM lau@climate.gsfc.nasa.gov RI Lau, William /E-1510-2012 OI Lau, William /0000-0002-3587-3691 NR 36 TC 17 Z9 17 U1 1 U2 4 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 J9 J CLIMATE JI J. Clim. PD NOV PY 2005 VL 18 IS 22 BP 4731 EP 4751 DI 10.1175/JCLI3561.1 PG 21 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 995DK UT WOS:000234079900010 ER PT J AU Wang, FY Milanovic, IM Zaman, KBMQ Povinelli, LA AF Wang, FY Milanovic, IM Zaman, KBMQ Povinelli, LA TI A quantitative comparison of delta wing vortices in the near-wake for incompressible and supersonic free streams SO JOURNAL OF FLUIDS ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article ID LEADING-EDGE VORTICES; VORTEX; FLOW; BREAKDOWN; SPEEDS AB When requiring quantitative data on delta wing vortices for design purposes, low-speed results have often been extrapolated to configurations intended for supersonic operation. This practice stems from a lack of database in high-speed flows due to measurement difficulties. In the present paper an attempt is made to examine this practice by comparing data from an incompressible flow experiment designed specifically to cot-respond to an earlier experiment in supersonic flows. The comparison is made for a 75 degrees sweptback delta wing at angles of attack of 7 degrees and 12 degrees. For the incompressible flow, detailed flow-field properties including vorticity and turbulence characteristics are obtained by hot-wire and pressure probe surveys. The results are compared, wherever possible, with available data from the earlier Mach 2.49 experiment. The results indicate that quantitative similarities exist in the distributions of total pressure and swirl velocities. Qualitative similarities also exist in other properties, however many differences are observed. The vortex core is smaller and rounded at low speed. At high speed, it is elongated in the spanwise direction near the trailing edge but goes through "axis switching" within a short distance downstream. The vortex is located farther outboard, i.e., the spacing between the two legs of the vortex pair is larger, at low speed. The axial velocity distribution within the core is significantly different in the two flow regimes. A "jet-like" profile, observed at low speed, either disappears or becomes "wake-like" at high speed. The axial velocity characteristics are examined in the light of an analytical model. C1 USDOT, John A Volpe Natl Transportat Syst Ctr, Cambridge, MA 02142 USA. Univ Hartford, Dept Mech Engn, Hartford, CT 06117 USA. NASA, John H Glenn Res Ctr Lewis Field, Cleveland, OH 44135 USA. RP Wang, FY (reprint author), USDOT, John A Volpe Natl Transportat Syst Ctr, Cambridge, MA 02142 USA. OI Milanovic, Ivana/0000-0002-9985-6014 NR 49 TC 1 Z9 1 U1 0 U2 1 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0098-2202 J9 J FLUID ENG-T ASME JI J. Fluids Eng.-Trans. ASME PD NOV PY 2005 VL 127 IS 6 BP 1071 EP 1084 DI 10.1115/1.2060732 PG 14 WC Engineering, Mechanical SC Engineering GA 984DJ UT WOS:000233282400003 ER PT J AU Yunck, TP Neilan, RE AF Yunck, TP Neilan, RE TI Integration of space geodesy: A US National Geodetic Observatory SO JOURNAL OF GEODYNAMICS LA English DT Article; Proceedings Paper CT 23rd General Assembly of the International-Union-of-Geodesy-and Geophysics CY JUL, 2003 CL Sapporo, JAPAN SP Int Union Geodesy & Geophys DE space geodesy; National Geodetic Observatory; INDIGO; Global Geodetic Observing System; Global Positioning System; Very Long Baseline Interferometry; Satellite Laser Ranging; GPS; VLBI; SLR; NGO; GGOS ID EARTH; CORE AB In the interest of improving the performance and efficiency of space geodesy it diverse group in the US, in collaboration with IGGOS, has begun to establish a unified National Geodetic Observatory (NGO). To launch this effort an international team will conduct a multi-year program of research into the technical issues of integrating SLR, VLBI. and GPS geodesy to produce a unified set of global geodetic products. The goal is to improve measurement accuracy by tip to an order of magnitude while lowering the cost to current sponsors. A secondary goal is to expand and diversify international sponsorship of space geodesy, Principal benefits will be to open new vistas of research in geodynamics and surface change while freeing scarce NASA funds for scientific studies. NGO will proceed in partnership with, and under the auspices of, the International Association of Geodesy (IAG) as an element of the Integrated Global Geodetic Observation System project. The collaboration will be conducted within. and will make full use of, the IAG's existing international services: the IGS, IVS, ILRS, and IERS. Seed funding for organizational activities and technical analysis will come from NASA's Solid Earth and Natural Hazards Program. Additional funds to develop an integrated geodetic data system known as Inter-service Data Integration for Geodetic Operations (INDIGO). will conic from a separate NASA program in Earth science information technology, INDIGO will offer ready access to the full variety of NASA's space geodetic data and will extend the GPS Seamless Archive (GSAC) philosophy to all space geodetic data types. (c) 2005 Published by Elsevier Ltd. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Yunck, TP (reprint author), CALTECH, Jet Prop Lab, M-S 306-416,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM tpy@jpl.nasa.gov; ruth.e.neilan@jpl.nasa.gov NR 13 TC 1 Z9 1 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0264-3707 J9 J GEODYN JI J. Geodyn. PD NOV-DEC PY 2005 VL 40 IS 4-5 BP 436 EP 449 DI 10.1016/j.jog.2005.06.007 PG 14 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 998OA UT WOS:000234327200010 ER PT J AU Moore, AW Neilan, RE AF Moore, AW Neilan, RE TI The International GPS Service tracking network: Enabling diverse studies and projects through international cooperation SO JOURNAL OF GEODYNAMICS LA English DT Article; Proceedings Paper CT 23rd General Assembly of the International-Union-of-Geodesy-and Geophysics CY JUL, 2003 CL Sapporo, JAPAN SP Int Union Geodesy & Geophys DE International GPS Service; infrastructure; application; collaboration; geodesy; GPS networks AB The International GPS Service (IGS), formulated beginning in 1989 and formalized in 1994, was founded on the collaborative operation of approximately 30 permanent GPS stations to benefit global geodynamics. The same cooperative principles, today applied to a network of over 300 stations, still serve to maximize global benefit without unnecessary duplication of investment in global infrastructure. The scope of applications of the dataset has grown to include atmospheric, oceanographic, subdaily, and low-earth orbiter activities through working groups and pilot projects fostered within the IGS in the now traditional IGS spirit of collaboration. These activities and the IGS infrastructure are viewed as critical elements to the Global Geodetic Observing System. This presentation will review the present nature of the IGS tracking network and its ability to support new applications. (c) 2005 Elsevier Ltd. All rights reserved. C1 CALTECH, Jet Prop Lab, IGS Cent Bur, Pasadena, CA 91109 USA. RP Moore, AW (reprint author), CALTECH, Jet Prop Lab, IGS Cent Bur, 4800 Oak Grove Dr,MS 238-540, Pasadena, CA 91109 USA. NR 8 TC 7 Z9 8 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0264-3707 J9 J GEODYN JI J. Geodyn. PD NOV-DEC PY 2005 VL 40 IS 4-5 BP 461 EP 469 DI 10.1016/j.jog.2005.10.009 PG 9 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 998OA UT WOS:000234327200012 ER PT J AU Pearlman, M Noll, C Dunn, P Horvath, J Husson, V Stevens, P Torrence, M Vo, H Wetzel, S AF Pearlman, M Noll, C Dunn, P Horvath, J Husson, V Stevens, P Torrence, M Vo, H Wetzel, S TI The International Laser Ranging Service and its support for IGGOS SO JOURNAL OF GEODYNAMICS LA English DT Article; Proceedings Paper CT 23rd General Assembly of the International-Union-of-Geodesy-and Geophysics CY JUL, 2003 CL Sapporo, JAPAN SP Int Union Geodesy & Geophys DE European Data Center; International Laser Ranging Service; International Earth Rotation Service AB The International Laser Ranging Service (ILRS) was established in September 1998 as a service within the IAG to support programs in geodetic, geophysical, and lunar research activities and to provide data products to the International Earth Rotation Service (IERS) in support of its prime objectives. Now in operation for 5 years,the ILRS develops: (1)the standards and specifications necessary for product consistency and (2) the priorities and tracking strategies required to maximize network efficiency. The service collects, merges, analyzes, archives and distributes satellite and lunar laser ranging data to satisfy a variety of scientific. engineering, and operational needs and encourages the application of new technologies to enhance the quality, quantity. and cost effectiveness of its data products. The ILRS works with: (1) the global network to improve station performance (2) new satellite missions in the design and building of retroreflector targets to maximize data quality and quantity and (3) science programs to optimize scientific data yield. The ILRS Central Bureau maintains a comprehensive web site as the primary vehicle for the distribution of information within the ILRS community. The site, which can be accessed at: http://ilrs.gsfc.nasa.gov is also available at mirrored sites at the Communications Research Laboratory (CRL) in Tokyo and the European Data Center (1,DC) in Munich. During the last 2 years, the ILRS has addressed very important challenges: (1) data from the field stations are now submitted hourly and made available immediately through the data centers for access by the user community (2) tracking on low satellites has been significantly improved through the sub-daily issue of predictions. drag functions. and the real-time exchange of time biases (3) analysis products are now submitted in SINEX format for compatibility with the other space geodesy techniques; (4) the Analysis Working Group is heavily engaged in Pilot Projects as it works toward an ILRS "standard" global solution and (5) SLR has significantly increased its participation in the International Terrestrial Reference Frame (ITRF) activity, which is important to the success of IGGOS. (c) 2005 Elsevier Ltd. All rights reserved. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Raytheon Informat Technol & Sci Serv, Lanham, MD 20706 USA. Honeywell Tech Solut Inc, Lanham, MD 20706 USA. RP Pearlman, M (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. EM mpearlman@cfa.harvard.edu; Carey.E.Noll@nasa.gov RI Noll, Carey/D-8884-2012 NR 0 TC 3 Z9 6 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0264-3707 J9 J GEODYN JI J. Geodyn. PD NOV-DEC PY 2005 VL 40 IS 4-5 BP 470 EP 478 DI 10.1016/j.jog.2005.06.009 PG 9 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 998OA UT WOS:000234327200013 ER PT J AU Willis, P Bar-Sever, YE Tavernier, G AF Willis, P Bar-Sever, YE Tavernier, G TI DORIS as a potential part of a Global Geodetic Observing System SO JOURNAL OF GEODYNAMICS LA English DT Article; Proceedings Paper CT 23rd General Assembly of the International-Union-of-Geodesy-and Geophysics CY JUL, 2003 CL Sapporo, JAPAN SP Int Union Geodesy & Geophys DE geodesy; DORIS; terrestrial reference frame; earthquake; Denali faults; Fairbanks; troposphere ID TERRESTRIAL REFERENCE FRAME; VERTICAL CRUSTAL MOTIONS; ORBIT DETERMINATION; SPACE SYSTEM; GPS; SERVICE; EARTH; DEFINITION; JASON-1; SPOT-2 AB We have processed all available DORIS data from all available satellites, except Jason-1 over the past 10 years (from January 1993 to April 2003). Weekly solutions have been produced for stations positions coordinates, geocenter motion and scale factor stability. We present here accuracy presently achievable for all types of potential geodetic products. Typically weekly stations positions can be derived with a repeatability of 1.0-1.5 cm, using data from 5 satellites simultaneously, showing the significant improvement in precision that has been gained recently using the additional new DORIS satellites. As an example, we show how such new results can detect displacement from large magnitude earthquakes, such as the 2003 Denali fault earthquake in Alaska. Displacements of -5 cm in latitude and +2 cm in longitude were easily detected using the DORIS data and are confirmed by recent GPS determination. The terrestrial reference frame was also well be monitored with DORIS during this 10-year period. Other geodetic products, such as tropospheric corrections for atmospheric studies are also analyzed. Finally, we discuss here the possible advantages and weaknesses of the DORIS system as additional geodetic tool, in conjunction with the already existing GPS, VLBI and SLR services, to participate in an Global Geodetic Observing System (GGOS). (c) 2005 Elsevier Ltd. All rights reserved. C1 Inst Geog Natl, Direct Tech, F-94160 St Mande, France. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Ctr Natl Etud Spatiales, DCT PO AL, F-31401 Toulouse 9, France. RP Willis, P (reprint author), Inst Geog Natl, Direct Tech, 2 Ave Pasteur,BP 68, F-94160 St Mande, France. EM Pascal.R.Willis@jpl.nasa.gov RI Willis, Pascal/A-8046-2008 OI Willis, Pascal/0000-0002-3257-0679 NR 35 TC 35 Z9 35 U1 1 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0264-3707 J9 J GEODYN JI J. Geodyn. PD NOV-DEC PY 2005 VL 40 IS 4-5 BP 494 EP 501 DI 10.1016/j.jog.2005.06.011 PG 8 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 998OA UT WOS:000234327200016 ER PT J AU Jardin, MR AF Jardin, MR TI Analytical relationships between conflict counts and air-traffic density SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS LA English DT Article; Proceedings Paper CT AIAA 4th Aviation Technology, Integration and Operations Forum (ATIO) CY SEP 20-22, 2004 CL Chicago, IL SP Amer Inst Aeronaut & Astronaut AB Semi-empirical random variable models of the expected number of air-traffic conflicts as a function of airtraffic density are derived. Model parameters are determined from analysis and simulation of real air-traffic data. These models are applied to simulated air-traffic scenarios to analyze conflict properties in various conflict resolution strategies. It is shown that under free routing conditions (approximated by great-circle routes in zerowind conditions) the expected number of conflicts is well represented by a binomial random variable model. Using this model, it is further demonstrated how conflict resolution can cause a chain reaction, leading to an increased number of conflicts for all aircraft, and how the model can be used to predict the airspace capacity for a given conflict resolution strategy. In a separate study, it is shown that for an iterative horizontal-plane conflict resolution strategy, a random variable model with the geometric distribution closely matches empirical data. This model also predicts the aircraft density at which the airspace becomes saturated. It is shown how analysis of conflicts in the horizontal plane can be scaled and applied to the analysis of conflicts in three-dimensional airspace. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Jardin, MR (reprint author), NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. NR 10 TC 2 Z9 2 U1 1 U2 1 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 NOV-DEC PY 2005 VL 28 IS 6 BP 1150 EP 1156 DI 10.2514/1.12758 PG 7 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 983ST UT WOS:000233253100007 ER PT J AU Vigo, I Garcia, D Chao, BF AF Vigo, I Garcia, D Chao, BF TI Change of sea level trend in the Mediterranean and Black seas SO JOURNAL OF MARINE RESEARCH LA English DT Article ID ATMOSPHERIC-PRESSURE; NORTH-ATLANTIC; TIDE GAUGES; DEEP-WATER; ALTIMETRY; TOPEX/POSEIDON; TEMPERATURE; VARIABILITY; SALINITY AB Sea level anomaly (SLA) data in the Mediterranean and Black seas obtained by ocean radar altimetry missions (TOPEX/Poseidon, Jason, ERS-1/2 and ENVISAT) are studied in conjunction with corresponding sea-surface temperature (SST) data. The studied time span is 11 years long, 1993-2003. Besides confirming previously published results, we report a significant, but enigmatic, abrupt change in the SLA trend that took place in mid-1999 which has been corroborated by independent tide gauge data. Results obtained from an Empirical Orthogonal Function (EOF) analysis show that the change in 1999 is not uniform in the Mediterranean Sea, which can thus be divided into 6 sub-regions. This 1999 kink in the rate-of-change happened in four of these sub-regions as well as in the Black Sea. Upon splitting the time series at mid-1999, we see a good spatial correlation for the first period between SLA and SST trend maps in both the Mediterranean Sea and the Black Sea, while for the second period such correlation virtually disappeared in the Mediterranean and is greatly reduced in the Black Sea. It implies that prior to 1999 the steric effect was a major factor in interannual variability of sea level in the Mediterranean and Black seas, but after the time the SLA inverted its trend in mid-1999, this steric effects became less important as a forcing factor. It is premature to draw conclusions about the physical processes involved based on the data sets we study, but it appears that the Mediterranean Sea might be seeing a restoration of Adriatic as the main source of deep water in the eastern basin, while the Black Sea level has been largely controlled by an interannual or interdecadal steric effect. C1 Univ Alicante, Dept Appl Math, Space Geodesy Lab, E-03080 Alicante, Spain. NASA, Goddard Space Flight Ctr, Space Geodesy Lab, Greenbelt, MD 20771 USA. RP Vigo, I (reprint author), Univ Alicante, Dept Appl Math, Space Geodesy Lab, E-03080 Alicante, Spain. EM vigo@ua.es RI Garcia-Garcia, David/L-7535-2014; Chao, Benjamin Fong/N-6156-2013 OI Garcia-Garcia, David/0000-0002-7273-9037; NR 30 TC 36 Z9 36 U1 0 U2 1 PU SEARS FOUNDATION MARINE RESEARCH PI NEW HAVEN PA YALE UNIV, KLINE GEOLOGY LAB, 210 WHITNEY AVENUE, NEW HAVEN, CT 06520-8109 USA SN 0022-2402 J9 J MAR RES JI J. Mar. Res. PD NOV PY 2005 VL 63 IS 6 BP 1085 EP 1100 DI 10.1357/002224005775247607 PG 16 WC Oceanography SC Oceanography GA 004VW UT WOS:000234781600005 ER PT J AU Kaul, AB Kleinsasser, AW Bumble, B LeDuc, HG Lee, KA AF Kaul, AB Kleinsasser, AW Bumble, B LeDuc, HG Lee, KA TI Aluminum nitride tunnel barrier formation with low-energy nitrogen ion beams SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID CURRENT-DENSITY; JUNCTIONS; FABRICATION; SURFACES; SILICON; MIXERS AB We report the use of low-energy nitrogen ion beams to form ultra-thin (< 2 nm) layers of AlNx to act as tunnel barriers in Nb/Al-AlNx/Nb Josephson junctions. We fabricated reproducible, high-quality devices with independent control of the ion energy and dose, enabling exploration of a wide parameter space. Critical current density J(c) ranged from 550 to 9400 A/cm(2) with subgap-to-normal resistance ratios from 50 to 12.6. The spatial variation of ion-current density was roughly correlated with J(c) over a large-area on a Si substrate. The junctions were stable on annealing up to temperatures of at least 200 degrees C. This technique could be applied to form other metal nitrides at room temperature for device applications where a high degree of control is desired. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. EM anu.kaul@jpl.nasa.gov NR 19 TC 3 Z9 3 U1 0 U2 1 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 32 AVENUE OF THE AMERICAS, NEW YORK, NY 10013-2473 USA SN 0884-2914 EI 2044-5326 J9 J MATER RES JI J. Mater. Res. PD NOV PY 2005 VL 20 IS 11 BP 3047 EP 3053 DI 10.1557/JMR.2005.0369 PG 7 WC Materials Science, Multidisciplinary SC Materials Science GA 981NN UT WOS:000233095400023 ER PT J AU Oh, JJ Drouin, BJ Cohen, EA AF Oh, JJ Drouin, BJ Cohen, EA TI The torsion-rotation spectrum of perchloric acid, HClO4 SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article DE HClO4; torsion-rotation spectrum; internal rotation; threefold barrier; quadrupole coupling; dipole moment ID INTERNAL-ROTATION; GROUND-STATE; AB-INITIO; VIBRATIONAL-STATE; BUTYL MERCAPTAN; ASYMMETRIC-TOP; GLOBAL FIT; MICROWAVE; STRATOSPHERE; SPECTROSCOPY AB The rotational spectrum of HClO4 has been observed in selected regions between 51.7 and 870 GHz. The molecule is a near spherical rotor with a moderately low barrier to internal rotation. The spectrum is characterized by strong mu(a), R-branch groupings with B + C = 5276.78 MHz. Although there are no E torsional states, the R-branches show three distinct groups of lines. There is a relatively tight cluster of symmetric rotor like transitions with K = 3n, a rather regular progression of transitions with K = 3n + 2 to high frequency and a less regular group of transitions with K = 3n + 1 to low frequency. Because the molecule is nearly spherical, the energy as a function of K is dominated by the K dependent solutions of the Mathieu equation. This unusual energy level distribution gives rise to numerous anomalous splittings and shifts due to avoided crossings within the K stacks as well as widely scattered mu(b) transitions. The fitting procedure will be described and the effective parameters will be presented. Rotational transitions of excited torsional states at and above the top of the barrier and the v(t) = 2-0 far infrared spectrum have been assigned. The dipole moment and the quadrupole coupling constants have been determined. Structural implications will be discussed. (c) 2005 Elsevier Inc. All rights reserved. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Sookmyung Womens Univ, Dept Chem, Seoul, South Korea. RP Cohen, EA (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Edward.A.Cohen@jpl.nasa.gov NR 44 TC 6 Z9 6 U1 1 U2 2 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-2852 J9 J MOL SPECTROSC JI J. Mol. Spectrosc. PD NOV PY 2005 VL 234 IS 1 BP 10 EP 24 DI 10.1016/j.jms.2005.07.012 PG 15 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 987SL UT WOS:000233537500002 ER PT J AU Predoi-Cross, A Hambrook, K Brawley-Tremblay, M Bouanich, JP Devi, VM Benner, DC Brown, LR AF Predoi-Cross, A Hambrook, K Brawley-Tremblay, M Bouanich, JP Devi, VM Benner, DC Brown, LR TI Measurements and theoretical calculations of self-broadening and self-shift coefficients in the v(2) band of CH3D SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article DE monodeuterated methane; CH3D; self-broadening; Fourier transform infrared spectroscopy; spectral lineshape ID MULTISPECTRUM FITTING TECHNIQUE; DIODE-LASER MEASUREMENTS; H-2-BROADENING COEFFICIENTS; LINE-INTENSITIES; 3-NU(2) BAND; NU(3) BAND; NU-2 BAND; (CH3D)-C-12; PARAMETERS; METHANE AB In this paper, we report measured Lorentz self-broadening and self-induced pressure-shift coefficients of (CH3D)-C-12 in the v(2) fundamental band (v(0) approximate to 2200 cm(-1)). The multispectrum fitting technique allowed us to analyze simultaneously seven self-broadened absorption spectra. All spectra were recorded at the McMath-Pierce Fourier transform spectrometer of the National Solar Observatory (NSO) on Kitt Peak, AZ with an unapodized resolution of 0.0056 cm(-1). Low-pressure (0.98-2.95 Torr) as well as high-pressure (17.5-303 Torr) spectra of C-12-enriched CH3D were recorded at room temperature to determine the pressure-broadening coefficients of 408 v2 transitions with quantum numbers as high as J" = 21 and K = 18, where K" = K' &3bond; K (for a parallel band). The measured self-broadening coefficients range from 0.0349 to 0.0896 cm(-1) atm(-1) at 296 K. All the measured pressure-shifts are negative. The reported pressure-induced self-shift coefficients vary from about -0.004 to -0.008 cm-1 atm-1. We have examined the dependence of the measured broadening and shift parameters on the J", and K quantum numbers and also developed empirical expressions to describe the broadening coefficients in terms of m (m = -J", J", and J' + 1 in the P-Q-, (Q)Q-, and R-Q-branch, respectively) and K. On average, the empirical expressions reproduce the measured broadening coefficients to within 3.6%. A semiclassical theory based upon the Robert-Bonamy formalism of interacting linear molecules has been used to calculate these self-broadening and self-induced pressure-shift coefficients. In addition to the electrostatic interactions involving the octopole and hexadecapole moments of CH3D, the intermolecular potential includes also an atom-atom Lennard-Jones model. For low K (K <= 3) with vertical bar m vertical bar < 8 the theoretical results of the broadening coefficients are in overall good agreement (3.0%) with the experimental data. For transitions with K approaching vertical bar m vertical bar, they are generally significantly underestimated (8.8%). The theoretical self-induced pressure shifts, whose vibrational contribution is derived from results in the (Q)Q-branch, are generally smaller in magnitude than the experimental data in the P-Q-, and R-Q-branches (15.2%). (c) 2005 Elsevier Inc. All rights reserved. C1 Univ Lethbridge, Dept Phys, Lethbridge, AB T1K 3M4, Canada. Univ Paris 11, CNRS, UPR 3361, Photophys Mol Lab, F-91405 Orsay, France. Coll William & Mary, Dept Phys, Williamsburg, VA 23187 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Predoi-Cross, A (reprint author), Univ Lethbridge, Dept Phys, 4401 Univ Dr, Lethbridge, AB T1K 3M4, Canada. EM Adriana.predoicross@uleth.ca NR 32 TC 12 Z9 12 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 0022-2852 J9 J MOL SPECTROSC JI J. Mol. Spectrosc. PD NOV PY 2005 VL 234 IS 1 BP 53 EP 74 DI 10.1016/j.jms.2005.08.005 PG 22 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 987SL UT WOS:000233537500006 ER PT J AU Pearson, JC Drouin, BJ AF Pearson, JC Drouin, BJ TI The ground state torsion-rotation spectrum of propargyl alcohol (HCCCH2OH) SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article ID SUBMILLIMETER-WAVE SPECTRUM; GAUCHE-ETHYL-ALCOHOL; INTERNAL-ROTATION; MICROWAVE-SPECTRUM; ASYMMETRIC MOLECULES; MILLIMETER-WAVE; ALLYL ALCOHOL; VIBRATION; SPECTROSCOPY; ASSIGNMENTS AB The rotation-torsion spectrum of the asymmetric frame-asymmetric top internal rotor propargyl alcohol (HCCCH2OH) has been extended into the millimeter and submillimeter wave spectral regions. Over 2000 ground torsional state transitions have been measured and analyzed up to rotational quantum numbers J = 80 and K-a = 33 through a frequency of 633 GHz. The newly measured transitions were added to approximately 200 previously reported and now unambiguously assigned microwave transitions to comprise a data set of 2390 transitions which has been fit to 59 kHz using a reduced axis method (RAM) Hamiltonian. The ground state has been confirmed to consist of a symmetric and an antisymmetric gauche conformer with no spectroscopic evidence of stable trans conformer. A complete set of rotation and distortion constants through 6th order and a number of the 8th and one 10th order constants for the normal species are presented along with those determined from a re-analysis of the existing OD species data. The a and b symmetry Coriolis interaction constants and the gauche+ gauche- tunnelling frequency of 652389.4 MHz has been determined for the OH species while the b symmetry Coriolis interaction and the 213480 MHz tunnelling frequency were determined for the OD species. (c) 2005 Elsevier Inc. All rights reserved. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Pearson, JC (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM John.C.Pearson@jpl.nasa.gov NR 31 TC 11 Z9 11 U1 0 U2 6 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-2852 J9 J MOL SPECTROSC JI J. Mol. Spectrosc. PD NOV PY 2005 VL 234 IS 1 BP 149 EP 156 DI 10.1016/j.jms.2005.08.013 PG 8 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 987SL UT WOS:000233537500016 ER PT J AU Shukla, S Ludwig, L Cho, HJ Duarte, J Seal, S AF Shukla, S Ludwig, L Cho, HJ Duarte, J Seal, S TI Effect of air-pressure on room temperature hydrogen sensing characteristics of nanocrystalline doped tin oxide MEMS-based sensor SO JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY LA English DT Article DE air-pressure; hydrogen; MEMS; nanocrystalline; sensor; tin oxide ID GAS SENSOR; THIN-FILM; INFRASTRUCTURE DEVELOPMENT; STORAGE; FUEL; THICKNESS; CO AB Nanocrystalline indium oxide (In2O3)-doped tin oxide (SnO2) thin film sensor has been sol-gel clip-coated on a microelectrochemical system (MEMS) device using 4 sol-gel dip-coating, technique. Hydrogen (H-2) at ppm-level has been successfully detected at room temperature using the present MEMS-based sensor. The room temperature H-2 sensing characteristics (sensitivity, response and recovery time, and recovery rate) of the present MEMS-based sensor has been investigated as a function of air-pressure (50-600 Torr) with, and Without the ultraviolet (UV) radiation exposure. It has been demonstrated that, the concentration of the surface-adsorbed oxygen-ions (which is related to the sensor-resistance in air), the ppm-level H-2 and the oxygen (O-2) partial pressure are the three major factors, which determine the variation in the room temperature H-2 sensing characteristics of the present MEMS-based sensor as a function of air-pressure. C1 Univ Cent Florida, Surface Engn & Nano Fabricat Lab, Adv Mat Proc & Anal Ctr, Orlando, FL 32816 USA. Univ Cent Florida, Dept Aerosp Engn, Orlando, FL 32816 USA. NASA, Kennedy Space Ctr, FL 32899 USA. RP Seal, S (reprint author), Univ Cent Florida, Surface Engn & Nano Fabricat Lab, Adv Mat Proc & Anal Ctr, Orlando, FL 32816 USA. OI Shukla, Satyajit/0000-0002-7947-8095 NR 30 TC 6 Z9 6 U1 0 U2 5 PU AMER SCIENTIFIC PUBLISHERS PI STEVENSON RANCH PA 25650 NORTH LEWIS WAY, STEVENSON RANCH, CA 91381-1439 USA SN 1533-4880 J9 J NANOSCI NANOTECHNO JI J. Nanosci. Nanotechnol. PD NOV PY 2005 VL 5 IS 11 BP 1864 EP 1874 DI 10.1166/jnn.2005.429 PG 11 WC Chemistry, Multidisciplinary; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 987RE UT WOS:000233534200015 PM 16433423 ER PT J AU Lian, YS Liou, MS AF Lian, YS Liou, MS TI Multi-objective optimization of transonic compressor blade using evolutionary algorithm SO JOURNAL OF PROPULSION AND POWER LA English DT Article ID ROTOR AB Multi-objective optimization is performed of the NASA rotor67 transonic compressor blade. The objectives are to maximize the stage pressure ratio, as well as to minimize the compressor weight. The backbones of the optimization approach consist of a genetic algorithm, a gradient-based method, and a response surface model. The genetic algorithm is used to facilitate the multi-objective optimization and to find the global optima of high-dimensional problems. The gradient-based method accelerates the optimization convergence rate. The response surface model, constructed to replace the computationally expensive analysis tool, reduces the computational cost. Representative solutions are selected from the Pareto-optimal front to verify against the computational fluid dynamics tool. Compared with the baseline design, some optimal solutions increase the stage pressure ratio by 1.8% and decrease the weight by 5.4%. A detailed study of flow structure near peak efficiency is presented by means of pressure distribution and streamlines inside boundary layers. Results show that the optimized blade favors a lighter weight by a thinner blade shape. The stage pressure rise is attributed to a reduced separation zone and a weakened shock wave. C1 Univ Michigan, Dept Aerosp Engn, Ann Arbor, MI 48109 USA. NASA, John H Glenn Res Ctr, Dept Aerosp Engn, Cleveland, OH 44135 USA. RP Lian, YS (reprint author), Univ Michigan, Dept Aerosp Engn, 1320 Beal Ave, Ann Arbor, MI 48109 USA. EM ylian@umich.edu NR 17 TC 32 Z9 36 U1 0 U2 9 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 NOV-DEC PY 2005 VL 21 IS 6 BP 979 EP 987 DI 10.2514/1.14667 PG 9 WC Engineering, Aerospace SC Engineering GA 987FB UT WOS:000233502700003 ER PT J AU Karabeyoglu, MA De Zilwa, S Cantwell, B Zilliac, G AF Karabeyoglu, MA De Zilwa, S Cantwell, B Zilliac, G TI Modeling of hybrid rocket low frequency instabilities SO JOURNAL OF PROPULSION AND POWER LA English DT Article; Proceedings Paper CT AIAA/ASME/SAE/ASEE 39th Joint Propulsion Conference CY JUL 20, 2003 CL Huntsville, AL SP AIAA, ASME, SAE, ASEE ID COMBUSTION AB A comprehensive dynamic model of a hybrid rocket has been developed to understand and predict the transient behavior including instabilities. A linearized version of the transient model predicted the low-frequency chamber pressure oscillations that are commonly observed in hybrids. The source of the instabilities is based on a complex coupling of thermal transients in the solid fuel, the wall heat transfer blocking due to fuel regression rate, and the transients in the boundary layer that forms on the fuel surface. The oscillation frequencies predicted by the linearized theory are in very good agreement with 43 motor test results obtained from the hybrid propulsion literature. The motor test data used in the comparison cover a very wide spectrum of parameters including 1) four separate research and development programs; 2) three different oxidizers (liquid oxygen, gaseous oxygen, and nitrous oxide); 3) a wide range of motor dimensions, that is, from 5 in. (12.7 cm) diameter to 72 in. (182.9 cm) diameter, and operating conditions; and 4) several fuel formulations. A simple universal scaling formula for the frequency of the primary oscillation mode is also suggested. C1 Stanford Univ, Dept Aeronaut & Astronaut, Stanford, CA 94305 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Karabeyoglu, MA (reprint author), Stanford Univ, Dept Aeronaut & Astronaut, Stanford, CA 94305 USA. NR 24 TC 10 Z9 10 U1 0 U2 6 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 NOV-DEC PY 2005 VL 21 IS 6 BP 1107 EP 1116 PG 10 WC Engineering, Aerospace SC Engineering GA 987FB UT WOS:000233502700017 ER PT J AU Jacquinet-Husson, N Scott, NA Chedin, A Garceran, K Armante, R Chursin, AA Barbe, A Birk, M Brown, LR Camy-Peyret, C Claveau, C Clerbaux, C Coheur, PF Dana, V Daumont, L Debacker-Barilly, MR Flaud, JM Goldman, A Hamdouni, A Hess, M Jacquemart, D Kopke, P Mandin, JY Massie, S Mikhailenko, S Nemtchinov, V Nikitin, A Newnham, D Perrin, A Perevalov, VI Regalia-Jarlot, L Rublev, A Schreier, F Schult, I Smith, KM Tashkun, SA Teffo, JL Toth, RA Tyuterev, VG Auwera, JV Varanasi, P Wagner, G AF Jacquinet-Husson, N Scott, NA Chedin, A Garceran, K Armante, R Chursin, AA Barbe, A Birk, M Brown, LR Camy-Peyret, C Claveau, C Clerbaux, C Coheur, PF Dana, V Daumont, L Debacker-Barilly, MR Flaud, JM Goldman, A Hamdouni, A Hess, M Jacquemart, D Kopke, P Mandin, JY Massie, S Mikhailenko, S Nemtchinov, V Nikitin, A Newnham, D Perrin, A Perevalov, VI Regalia-Jarlot, L Rublev, A Schreier, F Schult, I Smith, KM Tashkun, SA Teffo, JL Toth, RA Tyuterev, VG Auwera, JV Varanasi, P Wagner, G TI The 2003 edition of the GEISA/IASI spectroscopic database SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Review DE GEISA; GEISA/IASI; spectroscopic database; atmospheric absorption; CFC's cross-sections; atmospheric aerosols ID ABSORPTION CROSS-SECTIONS; ROTATIONAL LINE POSITIONS; M SPECTRAL REGION; ABSOLUTE INTENSITIES; MU-M; INFRARED-SPECTRA; CARBON-DIOXIDE; CM(-1) REGION; NU(5) BAND; HOT BANDS AB The content of the current (2003) version, GEISA/IASI-03, of the computer-accessible spectroscopic database, GEISA/IASI, is described. This "system" or database is comprised of three independent spectroscopic archives, which are (a) a database of individual spectral line parameters on 14 molecules, H2O, CO2, O-3, N2O, CO, CH4, O-2, NO, SO2, NO2, HNO3, OCS, C2H2, N-2, and the related 51 isotopomers and isotopologues, representing 702,550 entries, in the spectral range 599-3001 cm(-1), (b) a database of spectral absorption cross-sections (6,572,329 entries related to six molecules, CFC-11 CFC-12, CFC-14, HCFC-22, N2O5, CCl4), and a catalogue of microphysical and optical properties (mainly, the refractive indices) of atmospheric aerosols. The modifications and improvements, which have been implemented since the earlier editions of this database, in terms of content and management, have been explained in detail. GEISA/IASI has been created with the specific purpose of assessing the capability of measurement by the IASI instrument within the designated goals of ISSWG in the frame of the CNES/EUMETSAT European Polar System preparation. All the archived data can be handled through a user-friendly associated management software, which is posted on the ARA/LMD group web site at http://ara.lmd.polytechnique.fr. (c) 2005 Elsevier Ltd. All rights reserved. C1 Ecole Polytech, Inst Pierre Simon Laplace, Meteorol Dynam Lab, F-91128 Palaiseau, France. Russian Acad Sci, Inst Atmospher Opt, Lab Theoret Spect, Tomsk 634055, Russia. Univ Reims, Grp Spectrometrie Mol & Atmsopher, F-51062 Reims, France. German Aerosp Ctr, Remote Sensing Technol Inst, D-82234 Wessling, Germany. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Paris 06, Lab Phys Mol & Appl, F-75252 Paris, France. Univ Paris 06, Inst Pierre Simon Laplace, Serv Aeron, F-75252 Paris, France. RP Ecole Polytech, Inst Pierre Simon Laplace, Meteorol Dynam Lab, Route Dept 36, F-91128 Palaiseau, France. EM nicole.jacquinet@lmd.polytechnique.fr RI Nikitin, Andrei/K-2624-2013; Tashkun, Sergey/E-8682-2014; clerbaux, cathy/I-5478-2013 OI Nikitin, Andrei/0000-0002-4280-4096; NR 123 TC 130 Z9 131 U1 1 U2 16 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 NOV 1 PY 2005 VL 95 IS 4 BP 429 EP 467 DI 10.1016/j.jqsrt.2004.12.004 PG 39 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 937KE UT WOS:000229922200001 ER PT J AU Boissoles, J Domanskaya, A Boulet, C Tipping, RH Ma, Q AF Boissoles, J Domanskaya, A Boulet, C Tipping, RH Ma, Q TI New experimental measurements and theoretical analysis of the collision-induced absorption in N-2-H-2 pairs SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article DE collision-induced absorption; N-2-H-2 mixtures; high-temperature spectra ID FAR-INFRARED-ABSORPTION; MIXTURES; SPECTRA; DWARFS; H-2 AB We present new experimental data on the collision-induced fundamental absorption in N-2-H-2 mixtures at room temperature and at low enough pressures so that the binary contribution is dominant. Previous measurements have been made at pressures where the ternary and possibly higher absorption coefficients are significant, and this makes it difficult to obtain accurate values for the binary absorption enhancement coefficient. To obtain the enhancement spectrum from the measurements of the mixture, it is necessary to subtract out both the spectra of pure H-2 and N-2, along with some CO2 impurities thus increasing the experimental uncertainty. Nevertheless, we obtain a value for the integrated intensity of 1.15 x 10(-4) cm(-2) amagat(-2) that is in good agreement with the previous value of 1.38 x 10(-4). We also discuss how one can scale this result to high temperatures for application to brown dwarf or methane dwarf atmospheres. (c) 2005 Elsevier Ltd. All rights reserved. C1 Univ Alabama, Dept Phys & Astron, Tuscaloosa, AL 35487 USA. Univ Paris 11, CNRS, Photophys Mol Lab, Ctr Orsay, F-91405 Orsay, France. St Petersburg State Univ, Inst Phys, St Petersburg 198504, Russia. Univ Rennes 1, UMR PALMS, F-35042 Rennes, France. Columbia Univ, Dept Appl Phys, New York, NY 10025 USA. NASA, Goddard Space Flight Ctr, Inst Space Studies, New York, NY 10025 USA. RP Tipping, RH (reprint author), Univ Alabama, Dept Phys & Astron, POB 870324, Tuscaloosa, AL 35487 USA. EM rtipping@bama.ua.edu RI Domanskaya, Alexandra/A-5601-2011 OI Domanskaya, Alexandra/0000-0002-3934-6805 NR 19 TC 2 Z9 2 U1 1 U2 2 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 NOV 1 PY 2005 VL 95 IS 4 BP 489 EP 498 DI 10.1016/j.jqsrt.2004.12.006 PG 10 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 937KE UT WOS:000229922200004 ER PT J AU Snyder, V AF Snyder, V TI Comment on Exact analytical formula for Voigt spectral line profile SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Editorial Material DE Voigt function; complex error function; Fadeeva function ID COMPLEX ERROR FUNCTION; COMPUTATION AB The title Exact analytical formula for Voigt spectral line profile of the Note by Roston and Obaid (JQSRT 2005; 94:255-263) appears to promise something new and useful. In fact, it merely provides yet another integral representation for the Voigt function, that suggests a very inefficient computational approach. It provides no real evidence for the efficacy of the method, while ignoring a great deal of extant work. Our purpose here is to comment upon the deficiencies in that Note. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Snyder, V (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM van.snyder@jpl.nasa.gov NR 8 TC 0 Z9 0 U1 0 U2 5 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 NOV 1 PY 2005 VL 95 IS 4 BP 557 EP 558 DI 10.1016/j.jqsrt.2005.03.001 PG 2 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 937KE UT WOS:000229922200008 ER PT J AU Chen, YK Milos, FS AF Chen, YK Milos, FS TI Navier-Stokes solutions with finite rate ablation for planetary mission earth reentries SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article; Proceedings Paper CT AIAA 37th Thermophysics Conference CY JUN 28-JUL 01, 2004 CL Portland, OR SP AIAA ID THERMAL RESPONSE; SURFACE; GRAPHITE; PROGRAM AB A formulation of finite rate ablation surface boundary conditions, including oxidation, nitridation, and sublimation of carbonaceous material with pyrolysis gas injection, based on surface species mass conservation, has been developed. These surface boundary conditions are discretized and integrated with a Navier-Stokes solver. This numerical procedure can predict aerothermal heating, chemical species concentration, and carbonaceous material ablation rates over the heat-shield surface of reentry space vehicles. Two finite rate gas-surface interaction models, based on the work of Park and of Zhluktov and Abe, are considered. Three test cases are studied. The stream conditions of these test cases are typical for Earth reentry from a planetary mission with both oxygen and nitrogen fully or partially dissociated inside the shock layer. Predictions from both gas-surface interaction models are compared with those obtained by using chemical equilibrium ablation tables. Stagnation point convective heat fluxes predicted by using Park's finite rate model are usually below those obtained from chemical equilibrium tables and Zhluktov and Abe's model. Recession predictions from Zhluktov and Abe's model are usually lower than those obtained from Park's model and from chemical equilibrium tables. The effect of species mass diffusion on the predicted ablation rate is also examined. C1 NASA, Ames Res Ctr, Thermal Protect Mat & Syst Branch, Moffett Field, CA 94035 USA. RP Chen, YK (reprint author), NASA, Ames Res Ctr, Thermal Protect Mat & Syst Branch, Mail Stop 234-1, Moffett Field, CA 94035 USA. NR 26 TC 29 Z9 30 U1 0 U2 2 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 NOV-DEC PY 2005 VL 42 IS 6 BP 961 EP 970 DI 10.2514/1.12248 PG 10 WC Engineering, Aerospace SC Engineering GA 993UA UT WOS:000233979400001 ER PT J AU Szalai, C Chen, YK Loomis, M Thoma, B Buck, S AF Szalai, C Chen, YK Loomis, M Thoma, B Buck, S TI Mars Exploration Rover transverse impulse rocket cover thermal protection system design verification SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article; Proceedings Paper CT AIAA 36th Thermophysics Conference CY JUN 23-26, 2003 CL ORLANDO, FL SP AIAA AB Arc jet test results are summarized of the Mars Exploration Rover silicone-impregnated reusable ceramic ablator (SIRCA) transverse impulse rocket system (TIRS) cover test series in the Panel Test facility at NASA Ames Research Center. The primary objective of this arc jet test series was to evaluate design details of the SIRCA TIRS cover interface to the aeroshell under simulated atmospheric entry heating conditions. Four test articles were tested in an arc jet environment with three different seal configurations. The test condition was designed to match the predicted peak flight heat load at the gap region between the SIRCA and the backshell and resulted in an overtest for the apex region of the SIRCA TIRS cover. Repeatable thermocouple data were obtained and compared with SIRCA thermal response analyses. The one-dimensional thermal response prediction compared well with the thermocouple data for the location at the backshell interface. For the apex region of the SIRCA TIRS cover, a one-dimensional thermal response analysis resulted in an overprediction because there were strong multidimensional conduction effects due to the TIRS cover geometry. In general, the test results provide strong experimental evidence that supports the adequacy of the baseline seal design. C1 NASA, Ames Res Ctr, Thermal Protect Mat & Syst Branch, Moffett Field, CA 94035 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. NASA, Ames Res Ctr, Thermal Protect Mat & Syst Branch, Moffett Field, CA 94035 USA. RP Szalai, C (reprint author), NASA, Ames Res Ctr, Thermal Protect Mat & Syst Branch, Mail Stop 234-1, Moffett Field, CA 94035 USA. EM Christine.E.Szalai@nasa.gov NR 8 TC 0 Z9 0 U1 0 U2 1 PU AMER INST AERONAUTICS ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0022-4650 EI 1533-6794 J9 J SPACECRAFT ROCKETS JI J. Spacecr. Rockets PD NOV-DEC PY 2005 VL 42 IS 6 BP 990 EP 998 DI 10.2514/1.3637 PG 9 WC Engineering, Aerospace SC Engineering GA 993UA UT WOS:000233979400004 ER PT J AU Scallion, WI AF Scallion, WI TI Aerodynamic yaw controller for the space shuttle orbiter SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article AB A wind-tunnel investigation of the effectiveness of an aerodynamic yaw controller mounted on the lower surface of a Space Shuttle Orbiter model body flap was conducted in the Langley 31-Inch Mach 10 tunnel. The controller, consisting of a 60-deg delta fin mounted perpendicular to the body-flap lower surface and yawed 30 (leg to the freestream direction, was tested at orbiter angles of attack from 20 to 40 deg at zero sideslip for a Reynolds number based on the wing mean aerodynamic chord of 0.66 x 10(6). The aerodynamic control characteristics are presented with an analysis of the effectiveness of the controller in making a bank maneuver for Mach 18 flight conditions. The analysis shows that the controller is as effective as the reaction control system in initiating the bank maneuver. These results warrant further studies to determine the aerodynamic heating on the control surfaces and the effects of controller hinge-line cant angle and body-flap deflection on the controller effectiveness. C1 NASA Langley Res Ctr, Hampton, VA 23681 USA. RP Scallion, WI (reprint author), NASA Langley Res Ctr, Hampton, VA 23681 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 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 NOV-DEC PY 2005 VL 42 IS 6 BP 1005 EP 1010 DI 10.2514/1.12467 PG 6 WC Engineering, Aerospace SC Engineering GA 993UA UT WOS:000233979400006 ER PT J AU Jits, R Wright, M Chen, YK AF Jits, R Wright, M Chen, YK TI Closed-loop trajectory simulation for thermal protection system design for Neptune aerocapture SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article AB A configuration for aerocapture at Neptune is considered with all emphasis oil reduction of the overall aeroshell thermal protection system mass. The biconic vehicle is assumed to be capable of bank angle as wellas angle-of-attack modulation for guidance and optimal trajectory shaping. A methodology is presented for determining a nominal trajectory that robustly accommodates off-normal flight conditions with relatively small dispersions in integrated heat load. Such a trajectory, termed nominal robust, is presented for bank-only guidance. A nominal-robust trajectory is also generated for guidance with both angle-of-attack and hank modulation. Simulation of a nominal-robust trajectory with angle-of-attack modulation in the presence of multiple stacked off-iniminal conditions is described. The resulting reduction of maximum heat rate aid heat load relative to the undershoot and overshoot trajectories is quantified. The thermal protection system response based oil closed-loop trajectory simulations for worst-case off-nominal scenarios is calculated and compared with the traditional overshoot/undershoot thermal protection system design method. The results show that the use of the nominal-robust methodology results; ill a significant decrease in aeroshell mass, and that combined bank and angle-of-attack modulation further reduces trajectory dispersion and stagnation-point-integrated heat load as compared to pure bank-angle modulated trajectories. C1 NASA Ames Res Ctr, Natl Res Council, Moffett Field, CA 94035 USA. NASA Ames Res Ctr, Thermal Protect Mat Branch, Moffett Field, CA 94035 USA. RP Jits, R (reprint author), NASA Ames Res Ctr, Natl Res Council, MS 230-2 Reacting Flow Environm Branch, Moffett Field, CA 94035 USA. NR 20 TC 6 Z9 6 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 NOV-DEC PY 2005 VL 42 IS 6 BP 1025 EP 1034 DI 10.2514/1.13428 PG 10 WC Engineering, Aerospace SC Engineering GA 993UA UT WOS:000233979400009 ER PT J AU Simburger, EJ Lin, JK Scarborough, SE Curtis, HB AF Simburger, EJ Lin, JK Scarborough, SE Curtis, HB TI Development, design, and testing of PowerSphere multifunctional ultraviolet-rigidizable inflatable structures SO JOURNAL OF SPACECRAFT AND ROCKETS 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 AB The continuing advancement of microsatellites and nanosatellitestor space application has identified a need for a simple, low-mass, and low packing volume solar array system for these satellites. The result of decreasing satellite size, thus surface area, and increasing power demand as these satellites become more capable is the inevitable problem of power choke on satellite systems with body-mounted solar cells. The use of traditional, rigid, solar arrays necessitates larger stowage volume and mass, and also requires gimbals for pointing. In previous studies, the PowerSphere solar array system has been identified as one of the solutions to this power choke problem by lowering mass and stowage volume and eliminating pointing mechanisms. Given these requirements, ultraviolet cured composite materials have been identified as the best candidate for this application. The development of Power-Sphere multifunctional ultraviolet-rigidizable (UV-rigidizable) inflatable structures is beneficial not only to micro- and nanosatellites it also enables the advancement of gossamer-type structures. In conjunction with UV-rigidizable material, these structures incorporate thin-film flex-circuit to make them multifunctional. Two multifunctional structures in the Power-Sphere system use the UV-rigidizable material, namely, the inflatable hinge and the inflatable isogrid center column. C1 Aerosp Corp, Energy Convers & Test Sect, Elect & Photon Lab, El Segundo, CA 90245 USA. ILC Dover Inc, Space Deployable Struct Grp, Engn Dept, Frederica, DE 19946 USA. NASA John H Glenn Res Ctr, Res & Technol Dept, Cleveland, OH 44135 USA. RP Simburger, EJ (reprint author), Aerosp Corp, Energy Convers & Test Sect, Elect & Photon Lab, M2-275,2350 E El Segundo Blvd, El Segundo, CA 90245 USA. EM edward.j.simburger@acro.org; linj@ilcdovenr.com; scarbs@ilcdover.com; Henry.B.Curtis@grc.nasa.gov NR 8 TC 2 Z9 2 U1 1 U2 5 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 NOV-DEC PY 2005 VL 42 IS 6 BP 1091 EP 1100 DI 10.2514/1.3360 PG 10 WC Engineering, Aerospace SC Engineering GA 993UA UT WOS:000233979400017 ER PT J AU Meyer, CG Leifer, J Lopez, BC Jones, DC Caddell, BC AF Meyer, CG Leifer, J Lopez, BC Jones, DC Caddell, BC TI Zero- and one-g comparison of surface profile in single-curved parabolic membrane SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article; Proceedings Paper CT AIAA/ASME/ASCE/AHS/ASC 45th Structures, Structural Dynamics and Materials Conference CY APR 19-22, 2004 CL Palm Springs, CA SP Amer Inst Aeronaut & Astronaut, ASME, ASCE, AHS, ASC AB This experiment was designed to quantify the effects of gravity and boundary support conditions on a scale model of an orbiting, singly curved parabolic thin-film membrane antenna. A 1-m-scale model of the parabolic antenna and support system was constructed and tested on NASA's KC-135A Weightless Wonder microgravity aircraft. A fabric-backed membrane (76.2-mu m Nylon, 12.7-mu m Mylar, 12.7-mu m adhesive, 0.1-mu m Al) was placed in the test fixture designed for this work and tensioned using edge clamps that maintained the desired parabolic profile at the membrane boundaries. Targets for tracking the full-field surface deflection were provided by about 7000 3-mm dots stenciled on to the membrane surface. The membrane surface configuration was monitored by four digital cameras mounted in the test enclosure. Using photogrammetry, the high-resolution digital images taken in-flight (at 0-g conditions) and on the ground (at 1-g) were processed, and the three-dimensional location of each target visible in at least three images was calculated. It was found that under the same support conditions both structural wrinkling and sag in microgravity were significantly less pronounced than at I-g. C1 Univ Kentucky, Paducah, KY 42002 USA. CALTECH, Jet Propuls Lab, Pasadena, CA 91109 USA. RP Meyer, CG (reprint author), Univ Kentucky, Paducah, KY 42002 USA. NR 15 TC 3 Z9 3 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 NOV-DEC PY 2005 VL 42 IS 6 BP 1101 EP 1108 DI 10.2514/1.10913 PG 8 WC Engineering, Aerospace SC Engineering GA 993UA UT WOS:000233979400018 ER PT J AU Qian, FA Lutz, RR AF Qian, FA Lutz, RR TI Bi-directional safety analysis of product lines SO JOURNAL OF SYSTEMS AND SOFTWARE LA English DT Article DE product lines; software safety; software architecture; XML; reuse ID REUSE AB As product-line engineering becomes more widespread, more safety-critical software product lines are being built. This paper describes a structured method for performing safety analysis on a software product line, building on standard product-line assets: product-line requirements, architecture, and scenarios. The safety-analysis method is bi-directional in that it combines a forward analysis (from failure modes to effects) with a backward analysis (from hazards to contributing causes). Safety-analysis results are converted to XML files to allow automated consistency checking between the forward and backward analysis results and to support reuse of the safety-analysis results throughout the product line. The paper demonstrates and evaluates the method on a safety-critical product-line subsystem, the Door Control System. Results show that the bi-directional safety-analysis method found both missing and incorrect software safety requirements. Some of the new safety requirements affected all the systems in the product line while others affected only some of the systems in the product line. The results demonstrate that the proposed method can handle the challenges to safety analysis posed by variations within a product line. (c) 2005 Elsevier Inc. All rights reserved. C1 Iowa State Univ, Dept Comp Sci, Ames, IA 50011 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA. RP Lutz, RR (reprint author), Iowa State Univ, Dept Comp Sci, Ames, IA 50011 USA. EM qianfeng@cs.iastate.edu; rlutz@cs.iastate.edu NR 30 TC 0 Z9 0 U1 0 U2 3 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0164-1212 J9 J SYST SOFTWARE JI J. Syst. Softw. PD NOV PY 2005 VL 78 IS 2 BP 111 EP 127 DI 10.1016/j.jss.2005.02.028 PG 17 WC Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA 956YW UT WOS:000231337200002 ER PT J AU Ridruejo, A Pastor, JY LLorca, J Sayir, A Orera, VM AF Ridruejo, A Pastor, JY LLorca, J Sayir, A Orera, VM TI Stress corrosion cracking of single-crystal tetragonal ZrO2(Er2O3) SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID HYDROTHERMAL DEGRADATION; MECHANICAL-PROPERTIES; Y-TZP; TRANSFORMATION; ZIRCONIA; CERAMICS; GROWTH; SYSTEM; FIBERS; WATER AB The flexure strength of partially-stabilized tetragonal ZrO2(Er2O3) single-crystal monofilaments manufactured by the laser-heated floating zone method was measured as a function of the environment (air versus water) and temperature (from 25 degrees to 800 degrees C) at loading rates spanning three orders of magnitude to ascertain their susceptibility to the environmental conditions. These mechanical tests were completed with parallel tests on fully annealed monofilaments (to relieve the thermal residual stresses induced during growth) and by detailed analysis of the fracture surfaces using scanning electron microscopy and micro-Raman spectroscopy. While environmental susceptibility of ZrO2(Y2O3) in previous investigations was always associated with the destabilization of the tetragonal phase, monoclinic phase was not detected on the fracture surfaces of the ZrO2(Er2O3) monofilaments and it was concluded that slow crack growth in this material at high temperature or immersed in water was due to stress corrosion cracking. C1 Univ Politecn Madrid, Dept Mat Sci, ETS Ingn Caminos, E-28040 Madrid, Spain. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. Univ Zaragoza, CSIC, Inst Ciencia Mat Aragon, E-50009 Zaragoza, Spain. RP LLorca, J (reprint author), Univ Politecn Madrid, Dept Mat Sci, ETS Ingn Caminos, E-28040 Madrid, Spain. EM jllorca@mater.upm.es RI LLorca, Javier/C-1140-2013; orera, Victor/A-4213-2011; Ridruejo, Alvaro/I-1082-2015; OI LLorca, Javier/0000-0002-3122-7879; Ridruejo, Alvaro/0000-0002-8327-6090; Orera, Victor/0000-0001-9690-9064 NR 24 TC 7 Z9 8 U1 1 U2 3 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 NOV PY 2005 VL 88 IS 11 BP 3125 EP 3130 DI 10.1111/j.1551-2916.2005.00573.x PG 6 WC Materials Science, Ceramics SC Materials Science GA 976ZV UT WOS:000232773100022 ER PT J AU Larsen, ML Kostinski, AB Tokay, A AF Larsen, ML Kostinski, AB Tokay, A TI Observations and analysis of uncorrelated rain SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID FLUCTUATION PROPERTIES; RADAR; PRECIPITATION; UNIVERSE; STEADY; CLOUDS; MODEL AB Most microphysical models in precipitation physics and radar meteorology assume ( at least implicitly) that raindrops are completely uncorrelated in space and time. Yet, several recent studies have indicated that raindrop arrivals are often temporally and spatially correlated. Resolution of this conflict must begin with observations of perfectly uncorrelated rainfall, should such "perfectly steady rain" exist at all. Indeed, it does. Using data with high temporal precision from a two-dimensional video disdrometer and the pair-correlation function, a scale-localized statistical tool, several similar to 10-20-min rain episodes have been uncovered where no clustering among droplet arrival times is found. This implies that ( i) rain events exist where current microphysical models can be tested in an optimal manner and ( ii) not all rain can be properly described using fractals. C1 Michigan Technol Univ, Dept Phys, Houghton, MI 49931 USA. Univ Maryland Baltimore Cty, Joint Ctr Earth Syst Technol, Baltimore, MD 21228 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Michigan Technol Univ, Dept Phys, 1400 Townsend Dr, Houghton, MI 49931 USA. EM mllarsen@mtu.edu NR 28 TC 13 Z9 13 U1 0 U2 1 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 NOV PY 2005 VL 62 IS 11 BP 4071 EP 4083 DI 10.1175/JAS3583.1 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 986OW UT WOS:000233460600013 ER PT J AU Ding, LM Chang, DW Dai, LM Ji, T Li, SN Lu, JP Tao, Y Delozier, D Connell, J AF Ding, LM Chang, DW Dai, LM Ji, T Li, SN Lu, JP Tao, Y Delozier, D Connell, J TI Luminescent dendrons with oligo(phenylenevinylene) core branches and oligo(ethylene oxide) terminal chains SO MACROMOLECULES LA English DT Article ID LIGHT-EMITTING-DIODES; ELECTROCHEMICAL-CELLS; CONJUGATED POLYMERS; SIDE-CHAINS; ELECTROLUMINESCENCE; DENDRIMERS; GREEN; PHOTOPHYSICS; COPOLYMERS; QUINOLINE C1 Univ Dayton, Sch Engn, Dept Chem & Mat Engn, Dayton, OH 45469 USA. Univ Akron, Dept Polymer Engn, Akron, OH 44325 USA. Natl Res Council Canada, Inst Microstruct Sci, Ottawa, ON K1A 0R6, Canada. NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Dai, LM (reprint author), Univ Dayton, Sch Engn, Dept Chem & Mat Engn, Dayton, OH 45469 USA. EM Idai@udayton.edu RI Ding, Liming/C-6050-2013 NR 34 TC 8 Z9 8 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD NOV 1 PY 2005 VL 38 IS 22 BP 9389 EP 9392 DI 10.1021/ma0506233 PG 4 WC Polymer Science SC Polymer Science GA 979WO UT WOS:000232975900057 ER PT J AU Nguyen, CV Ye, Q Meyyappan, M AF Nguyen, CV Ye, Q Meyyappan, M TI Carbon nanotube tips for scanning probe microscopy: fabrication and high aspect ratio nanometrology SO MEASUREMENT SCIENCE AND TECHNOLOGY LA English DT Article DE atomic force microscopy; carbon nanotube tips; chemical vapour deposition; imaging high aspect ratio features; wafer scale fabrication ID ATOMIC-FORCE MICROSCOPY; LATERAL RESOLUTION; GROWTH AB The atomic force microscope (AFM) is being adapted by industry as a tool for in line fabrication metrology. The last two decades have witnessed the evolution of the AFM into a versatile instrument, with many new scanning force techniques presently being developed. Consequently, the AFM has wide industrial applications from conventional surface roughness measurement of thin films to the characterization of magnetic domains as related to the information storage industry. There are a number of challenges that must be resolved in order to fully realize the potential of AFM as future nanoscale inspection tools for the information technology industry. Improvement in AFM tip technology is one of the most important factors for AFM to be fully adapted by industry. This paper reviews the development and application of carbon nanotube AFM tips, highlighting the progress from our lab. Many applications for carbon nanotube AFM tips have been demonstrated for scanning probe microscopy; however, herein we focus mainly on the measurement of high aspect ratio nanostructures. The structure of carbon nanotubes will be described in relationship to the application of the AFM tip. Fabrication techniques for carbon nanotube AFM probes will be highlighted, including an example detailing a high throughput large-scale production method. Data demonstrating the capability of carbon nanotube tips for imaging high aspect ratio features will be compared with conventional top-down SEM metrology. This review will also address some of the technical challenges that still remain for the full implementation of carbon nanotube AFM tip technology for industrial applications. C1 NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. RP NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. EM cvnguyen@mail.arc.nasa.gov NR 29 TC 51 Z9 52 U1 1 U2 15 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0957-0233 EI 1361-6501 J9 MEAS SCI TECHNOL JI Meas. Sci. Technol. PD NOV PY 2005 VL 16 IS 11 BP 2138 EP 2146 DI 10.1088/0957-0233/16/11/003 PG 9 WC Engineering, Multidisciplinary; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 986MK UT WOS:000233453500004 ER PT J AU Orji, NG Vorburger, TV Fu, J Dixson, RG Nguyen, CV Raja, J AF Orji, NG Vorburger, TV Fu, J Dixson, RG Nguyen, CV Raja, J TI Line edge roughness metrology using atomic force microscopes SO MEASUREMENT SCIENCE AND TECHNOLOGY LA English DT Article DE atomic force microscope; line edge roughness; carbon nanotube ID 193 NM; SURFACE; SIMULATION; LITHOGRAPHY; PERFORMANCE; AFM; LER; CD AB Line edge roughness (LER) measurements using two types of atomic force microscopes and three types of tips are compared. Measurements were made on specially prepared samples with inscribed edge roughness of different amplitudes and wavelengths. The spatial wavelengths and amplitudes each instrument was able to measure are compared. Techniques on checking the noise level of LER measuring instruments are highlighted. C1 NIST, Gaithersburg, MD 20899 USA. NASA, Ames Res Ctr, ELORET Corp, Moffett Field, CA 94033 USA. Univ N Carolina, Charlotte, NC 28223 USA. RP NIST, Gaithersburg, MD 20899 USA. NR 20 TC 28 Z9 31 U1 0 U2 5 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0957-0233 EI 1361-6501 J9 MEAS SCI TECHNOL JI Meas. Sci. Technol. PD NOV PY 2005 VL 16 IS 11 BP 2147 EP 2154 DI 10.1088/0957-0233/16/11/004 PG 8 WC Engineering, Multidisciplinary; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 986MK UT WOS:000233453500005 ER PT J AU Park, Y Wright, JD Jensen, JDL King, GC Choi, SH AF Park, Y Wright, JD Jensen, JDL King, GC Choi, SH TI Diffraction analysis for periodic nano-scale apertures, scatterers and absorbers SO MEASUREMENT SCIENCE AND TECHNOLOGY LA English DT Article DE Fraunhofer diffraction; 2D grating; optical characterization; e-beam lithography; nanometrology; calibration; Rayleigh criterion ID SUBWAVELENGTH HOLE ARRAYS; TRANSMISSION AB We developed a laser diffraction measurement method to characterize periodic arrays of nano-structures including nano-scale apertures, scatterers and absorbers. The new method is very sensitive to the shapes, sizes, periodicities and alignments of tiny structures which are even smaller than the wavelength of light. The structures with a dimension of 400 nm were measured with a 532 nm laser, using a diffraction method. A good correlation was found between the theoretical calculation and experimental measurement on a sample with millions of sub-wavelength apertures which were fabricated with e-beam lithography. C1 Sci & Technol Corp, Hampton, VA 23666 USA. Tabb HS, Yorktown, VA 23693 USA. Grafton HS, Yorktown, VA 23692 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Sci & Technol Corp, Hampton, VA 23666 USA. EM y.park@larc.nasa.gov NR 11 TC 3 Z9 3 U1 0 U2 5 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0957-0233 EI 1361-6501 J9 MEAS SCI TECHNOL JI Meas. Sci. Technol. PD NOV PY 2005 VL 16 IS 11 BP 2208 EP 2212 DI 10.1088/0957-0233/16/11/011 PG 5 WC Engineering, Multidisciplinary; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 986MK UT WOS:000233453500012 ER PT J AU Ostro, SJ Benner, LAM Magri, C Giorgini, JD Rose, R Jurgens, RF Yeomans, DK Hine, AA Nolan, MC Scheeres, DJ Broschart, SB Kaasalainen, M Margot, JL AF Ostro, SJ Benner, LAM Magri, C Giorgini, JD Rose, R Jurgens, RF Yeomans, DK Hine, AA Nolan, MC Scheeres, DJ Broschart, SB Kaasalainen, M Margot, JL TI Radar observations of Itokawa in 2004 and improved shape estimation SO METEORITICS & PLANETARY SCIENCE LA English DT Article ID 1998 SF36; MODEL AB We present June 2004 radar images of asteroid 25143 Itokawa (1998 SF36) that improve upon the longitude-latitude coverage of images obtained in 2001 by Ostro et al. (2004) and use the 2001-2004 data to refine that paper's constraints oil Itokawa's shape. The 2004 images,. the first of the asteroid's southern side, look distinctly different from the 2001 images, revealing leading edges that are much more curved and rugged than the nearly convex leading edges seen at northern latitudes in 2001. Itokawa is shaped like a slightly asymmetrical, bent, lumpy ellipsoid with dimensions along the principal axes within 10% of 594 x 320 x 288 in. To illustrate the uncertainty space associated with shape reconstruction from images with suboptimal orientational coverage, we present two alternative three-dimensional models of the object. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Maine, Farmington, ME 04938 USA. Natl Astron & Ionosphere Ctr, Arecibo Observ, Arecibo, PR 00612 USA. Univ Michigan, Dept Aerosp, Ann Arbor, MI 48109 USA. Univ Helsinki, Rolf Nevanlinna Inst, FIN-00014 Helsinki, Finland. Oulu Univ, Sodankyla Geophys Observ, FIN-99600 Sodankyla, Finland. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. RP Ostro, SJ (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM ostro@reason.jpl.nasa.gov RI Margot, Jean-Luc/A-6154-2012; Nolan, Michael/H-4980-2012; Kaasalainen, Mikko/G-4236-2014 OI Margot, Jean-Luc/0000-0001-9798-1797; Nolan, Michael/0000-0001-8316-0680; NR 9 TC 16 Z9 17 U1 0 U2 0 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 NOV PY 2005 VL 40 IS 11 BP 1563 EP 1574 PG 12 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 003SI UT WOS:000234701500001 ER PT J AU Righter, K Collins, SJ Brandon, AD AF Righter, K Collins, SJ Brandon, AD TI Mineralogy and petrology of the LaPaz Icefield lunar mare basaltic meteorites SO METEORITICS & PLANETARY SCIENCE LA English DT Article ID EQUILIBRIA; HISTORY; GLASSES; IRON; PETROGENESIS; CHEMISTRY; SPINELS; MANTLE; STATES; FE2O3 AB Five basaltic meteorites from the LaPaz ice field are paired on the basis of their mineralogy and texture, and represent a unique basalt type distinct from those in the Apollo or Luna sample collections. LaPaz Icefield (LAP) 02205, LAP 02224, LAP 02226, LAP 02436 and LAP 03632 all contain plagioclase, pyroxene, ilmenite, spinel, olivine, and minor troilite, metal, phosphate, baddeleyite and silica (cristobalite). Brown glassy melt veins are ubiquitous and cross the primary igneous texture. Plagioclase, the major mineral and occurring as laths in a subophitic texture is of narrow compositional range, from An(85-89). Pyroxene, also a major mineral, is strongly zoned, from augite and pigeonite cores to very iron-rich rims. Ilmenite laths comprise approximately 3-5% of the basalts. Spinels show a large compositional range, comparable to that documented in Apollo 15 basalts, indicating ail early chromite-rich stage followed by an intermediate to late stage with Cr-rich ulvospinel. Relatively large, subhedral to skeletal olivine crystals (Fo(46-62)) are sparse.. and are too Fo-rich to be in equilibrium with the bulk rock, indicating that these are xenocrysts rather than phenocrysts. The presence of melt veins with a similar composition to the bulk rock.. maskelynitized plagioclase feldspar, and metastable cristobalite indicate that these rocks underwent significant shock, between 30 and 50 GPa. Calculated oxygen fugacity, using spinel-ilmenite-iron metal equilibria, is within the range defined by previous studies of lunar materials. The bulk composition (low MgO) and low calculated temperatures, together with modelling calculations, indicate ail origin by fractional crystallization of a more primitive low TiO2) parent liquid similar to Apollo 12 olivine basalt. C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Univ London Imperial Coll Sci Technol & Med, London SW7 2AZ, England. RP Righter, K (reprint author), NASA, Lyndon B Johnson Space Ctr, Mail Code KT, Houston, TX 77058 USA. EM kevin.righter-1@nasa.gov NR 65 TC 20 Z9 20 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 NOV PY 2005 VL 40 IS 11 BP 1703 EP 1722 PG 20 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 003SI UT WOS:000234701500009 ER PT J AU Huang, JL Xu, Y Gogarten, JP AF Huang, JL Xu, Y Gogarten, JP TI The presence of a haloarchaeal type tyrosyl-tRNA synthetase marks the opisthokonts as monophyletic SO MOLECULAR BIOLOGY AND EVOLUTION LA English DT Article DE ancient gene transfer; opisthokonts; tyrosyl-tRNA synthetase; eukaryotic evolution ID HORIZONTAL GENE-TRANSFER; MULTIPLE SEQUENCE ALIGNMENT; PHYLOGENETIC ANALYSIS; MAXIMUM-LIKELIHOOD; EVOLUTION; EUKARYOTES; FUNGI; ARCHAEBACTERIA; EUBACTERIA; INNOVATION AB Lateral gene transfer plays an important role in the evolution of life. Events of ancient gene transfer can transmit genetic novelties to descendent lineages and subsequently shape their genetic systems. We here present the analyses of the gene encoding tyrosyl-tRNA synthetase (tyrRS), which reveal two eukaryotic tyrRS lineages, one including the opisthokonts and the other the remaining eukaryotes. The different origins of tyrRS lineages between the opisthokonts and the remaining eukaryotes indicate a likely case of ancient lateral gene transfer of tyrRS from an archaeon to the opisthokonts, which lends further support for the monophyly of the latter group. Ancient paralogy followed by differential gene loss is an alternative, albeit less parsimonious explanation for the distribution of the two eukaryotic tyrRS types. In either case, the presence of a haloarchaeal tyrRS type in the opisthokonts marks this group as monophyletic. This finding also points to the potential utility of ancient gene transfer events as molecular markers for major organismal lineages. C1 E Carolina Univ, Dept Biol, Greenville, NC 27858 USA. Marine Biol Lab, NASA, Astrobiol Inst, Woods Hole, MA 02543 USA. Univ Connecticut, Dept Mol & Cell Biol, Storrs, CT 06269 USA. Univ Georgia, Dept Biochem & Mol Biol, Athens, GA 30602 USA. RP Huang, JL (reprint author), E Carolina Univ, Dept Biol, Greenville, NC 27858 USA. EM huangj@mail.ecu.edu OI Gogarten, Johann Peter/0000-0001-6459-6518 NR 36 TC 33 Z9 38 U1 0 U2 1 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 NOV PY 2005 VL 22 IS 11 BP 2142 EP 2146 DI 10.1093/molbev/msi221 PG 5 WC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity GA 972AP UT WOS:000232426500004 PM 16049196 ER PT J AU Blair, JE Hedges, SB AF Blair, JE Hedges, SB TI Molecular phylogeny and divergence times of deuterostome animals SO MOLECULAR BIOLOGY AND EVOLUTION LA English DT Review DE molecular clock; timetree; genomes; Chordata; Vertebrata ID COMPLETE MITOCHONDRIAL-DNA; COELACANTH LATIMERIA-CHALUMNAE; NEOPROTEROZOIC SNOWBALL EARTH; RIBOSOMAL-RNA SEQUENCES; 18S RDNA SEQUENCES; EVOLUTIONARY RELATIONSHIPS; CARTILAGINOUS FISHES; VERTEBRATE EVOLUTION; DOUSHANTUO FORMATION; MAXIMUM-LIKELIHOOD AB The phylogenetic relationships among deuterostome animals have been debated for many years, and a diversity of hypotheses have been proposed based on both morphological and molecular data. Here we have assembled sequences of 217 nuclear-encoded proteins to address specific questions concerning their relationships and times of origin. We recovered significant support for urochordates as the closest relative of vertebrates with an analysis of 59 proteins (17,400 amino acids) and suggest that the basal position of urochordates found in previous molecular studies may have been the result of long-branch attraction biases. Our results also support Ambulacraria, the pairing of hemichordates with echinoderms (nine proteins; 2,382 amino acids), and Cyclostomata, the pairing of lampreys with hagfish (25 proteins; 6,895 amino acids). In addition, 325 shared proteins (102,110 amino acids) were obtained from the complete genomes of six vertebrates and a urochordate for phylogenetic analysis and divergence time estimation. An evolutionary timescale was estimated using a local (Bayesian) molecular clock method. We found that most major lineages of deuterostomes arose prior to the Cambrian Explosion of fossils (similar to 520 MYA) and that several lineages had originated before periods of global glaciation in the Precambrian. C1 Penn State Univ, NASA, Astrobiol Inst, University Pk, PA 16802 USA. Penn State Univ, Dept Biol, University Pk, PA 16802 USA. RP Blair, JE (reprint author), Penn State Univ, NASA, Astrobiol Inst, University Pk, PA 16802 USA. EM jeb322@psu.edu NR 121 TC 243 Z9 255 U1 6 U2 64 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0737-4038 EI 1537-1719 J9 MOL BIOL EVOL JI Mol. Biol. Evol. PD NOV PY 2005 VL 22 IS 11 BP 2275 EP 2284 DI 10.1093/molbev/msi225 PG 10 WC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity GA 972AP UT WOS:000232426500017 PM 16049193 ER PT J AU Waskett, TJ Eales, SA Gear, WK McCracken, HJ Lilly, S Brodwin, M AF Waskett, TJ Eales, SA Gear, WK McCracken, HJ Lilly, S Brodwin, M TI XMM-Newton surveys of the Canada-France Redshift Survey Fields - III. The environments of X-ray selected active galactic nuclei at 0.4 < z < 0.6 SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE galaxies : active; X-rays : galaxies; galaxies : evolution ID RADIO-QUIET QUASARS; DIGITAL SKY SURVEY; MINOR MERGERS; INTERMEDIATE-REDSHIFT; CLUSTER ENVIRONMENTS; GALAXY CLUSTERS; HOST GALAXIES; LOUD QUASARS; EVOLUTION; CATALOGS AB The environmental properties of a sample of 31 hard X-ray selected active galactic nuclei (AGN) are investigated, from scales of 500 kpc down to 30 kpc, and are compared to a control sample of inactive galaxies. All the AGN lie in the redshift range 0.4 < z < 0.6. The accretion luminosity density of the Universe peaks close to this redshift range, and the AGN in the sample have X-ray luminosities close to the knee in the hard X-ray luminosity function, making them representative of the population that dominated this important phase of energy conversion. Using both the spatial clustering amplitude and near-neighbour counts, it is found that the AGN have environments that are indistinguishable from normal, inactive galaxies over the same redshift range and with similar optical properties. Typically, the environments are of subcluster richness, in contrast to similar studies of high-z quasars, which are often found in clusters with comparable richness to the Abell R >= 0 clusters. It is suggested that minor mergers with low-mass companions are a likely candidate for the mechanism by which these modest luminosity AGN are fuelled. C1 Univ Cardiff Wales, Dept Phys & Astron, Cardiff CF24 3YB, Wales. Inst Astrophys, F-75014 Paris, France. Dept Phys, CH-8093 Zurich, Switzerland. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Waskett, TJ (reprint author), Univ Cardiff Wales, Dept Phys & Astron, POB 913, Cardiff CF24 3YB, Wales. EM Tim.Waskett@astro.cf.ac.uk NR 31 TC 18 Z9 18 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 NOV 1 PY 2005 VL 363 IS 3 BP 801 EP 810 DI 10.1111/j.1365-2966.2005.09480.x PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 975JY UT WOS:000232659500007 ER PT J AU Champion, DJ Lorimer, DR McLaughlin, MA Xilouris, KM Arzoumanian, Z Freire, PCC Lommen, AN Cordes, JM Camilo, F AF Champion, DJ Lorimer, DR McLaughlin, MA Xilouris, KM Arzoumanian, Z Freire, PCC Lommen, AN Cordes, JM Camilo, F TI Arecibo timing and single-pulse observations of 17 pulsars SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE radiation mechanisms : non-thermal; pulsars : general; pulsars : individual : PSR J0815+0939; pulsars : individual : PSR J1829+2456; pulsars : individual : PSR J1944+0907 ID MILLISECOND PULSARS; GALACTIC PLANE; BINARY PULSAR; RADIO PULSARS; PROPER MOTIONS; DISCOVERY; SEARCH; SYSTEM; VELOCITIES; RADIATION AB We report on timing and single-pulse observations of 17 pulsars discovered at the Arecibo Observatory. The highlights of our sample are the recycled pulsars J1829+ 2456, J1944+ 0907 and the drifting subpulses observed in PSR J0815+ 0939. For the double neutron star binary J1829+ 2456, in addition to improving upon our existing measurement of relativistic periastron advance, we have now measured the pulsar's spin-period derivative. This new result sets an upper limit on the transverse speed of 120 km s(-1) and a lower limit on the characteristic age of 12.4 Gyr. From our measurement of proper motion of the isolated 5.2-ms pulsar J1944+ 0907, we infer a transverse speed of 188 +/- 65 km s(-1). This is higher than that of any other isolated millisecond pulsar. An estimate of the speed, using interstellar scintillation, of 235 +/- 45 km s(-1) indicates that the scattering medium along the line of sight is non-uniform. We discuss the drifting subpulses detected from three pulsars in the sample, in particular the remarkable drifting subpulse properties of the 645-ms pulsar J0815+ 0939. Drifting is observed in all four components of the pulse profile, with the sense of drift varying among the different components. This unusual 'bi-drifting' behaviour challenges standard explanations of the drifting subpulse phenomenon. C1 Univ Manchester, Jodrell Bank Observ, Macclesfield SK11 9DL, Cheshire, England. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. NASA, Goddard Space Flight Ctr, USRA EUD, Greenbelt, MD 20771 USA. Arecibo Observ, Natl Astron & Ionosphere Ctr, Arecibo, PR 00612 USA. Franklin & Marshall Coll, Dept Phys & Astron, Lancaster, PA 17604 USA. Cornell Univ, Dept Astron & Space Sci, Ithaca, NY 14853 USA. Columbia Univ, Columbia Astrophys Lab, New York, NY 10027 USA. RP Champion, DJ (reprint author), Univ Manchester, Jodrell Bank Observ, Macclesfield SK11 9DL, Cheshire, England. EM champion@jb.man.ac.uk OI Champion, David/0000-0003-1361-7723 NR 57 TC 39 Z9 40 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 NOV 1 PY 2005 VL 363 IS 3 BP 929 EP 936 DI 10.1111/j.1365-2966.2005.09499.x PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 975JY UT WOS:000232659500020 ER PT J AU Wu, LG Wang, B Braun, SA AF Wu, LG Wang, B Braun, SA TI Impacts of air-sea interaction on tropical cyclone track and intensity SO MONTHLY WEATHER REVIEW LA English DT Article ID RESOLUTION COUPLED MODEL; UPPER OCEAN RESPONSE; HURRICANE INTENSITY; NUMERICAL-MODEL; MOTION; FLOW; ATMOSPHERE; SIMULATIONS; THERMOCLINE; VORTEX AB While the previous studies of the impacts of air-sea interaction on tropical cyclones (TCs) generally agree on significant reduction in intensity and little change in track, they did not further explore the relative roles of the weak symmetric and strong asymmetric sea surface temperature (SST) anomalies relative to the TC center. These issues are investigated numerically with a coupled hurricane-ocean model in this study. Despite the relatively small magnitude compared to the asymmetric component of the resulting cooling, the symmetric cooling plays a decisive role in weakening TC intensity. A likely reason is that the symmetric cooling directly reduces the TC intensity, while the asymmetric cooling affects the intensity through the resulting TC asymmetries, which are mainly confined to the lower boundary and much weaker than those resulting from large-scale environmental influences. The differences in TC tracks between the coupled and fixed SST experiments are generally small because of the competing processes associated with the changes in TC asymmetries and the beta drift induced by air-sea interaction. The symmetric component of the SST drop weakens the TC intensity and outer strength, leading to a more northward beta drift. On the other hand, since the asymmetric component of the SST cooling is negative in the rear and positive in the front of a TC in the coupled experiments, the enhanced diabatic heating is on the southern side of a westward-moving TC, tending to shift the TC southward. In the coupled model the westward TCs with relatively weak (strong) outer strength tend to turn to the north (south) of the corresponding TCs without air-sea interaction. C1 NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. Univ Maryland Baltimore Cty, Goddard Earth & Technol Ctr, Baltimore, MD 21228 USA. Univ Hawaii Manoa, Dept Meteorol, Sch Ocean & Earth Sci & Technol, Honolulu, HI 96822 USA. RP Wu, LG (reprint author), NASA, Goddard Space Flight Ctr, Atmospheres Lab, Code 912, Greenbelt, MD 20771 USA. EM liguang@agnes.gsfc.nasa.gov NR 43 TC 26 Z9 33 U1 2 U2 8 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 NOV PY 2005 VL 133 IS 11 BP 3299 EP 3314 DI 10.1175/MWR3030.1 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 986OQ UT WOS:000233460000013 ER PT J AU Matuszczak, Y Farid, M Jones, J Lansdowne, S Smith, MA Taylor, AA Reid, MB AF Matuszczak, Y Farid, M Jones, J Lansdowne, S Smith, MA Taylor, AA Reid, MB TI Effects of N-acetylcysteine on glutathione oxidation and fatigue during handgrip exercise SO MUSCLE & NERVE LA English DT Article DE antioxidant; exercise; glutathione; oxidative stress; skeletal muscle ID SKELETAL-MUSCLE; RAT DIAPHRAGM; IN-VITRO; ENDURANCE; CYSTEINE; SUPPLEMENTATION; CONTRACTION; PERFORMANCE; SUPEROXIDE; INFUSION AB Fatigue of hand and forearm muscle groups can limit task performance by astronauts wearing space suits. Countermeasures to delay fatigue would therefore be useful to the space program. N-acetylcysteine (NAC) has been shown to inhibit fatigue during other tasks so we tested its effects during handgrip exercise. Volunteers practiced isometric handgrip maneuvers until performance was reproducible over three successive sessions (baseline). Performance then was retested after ingesting NAC (150 mg.kg(-1)) or saline. Drug administration increased NAC and cysteine blood levels (P < 0.001). Performance of sustained maximal efforts was unaffected. During repetitive submaximal efforts, NAC delayed fatigue (130% baseline) and inhibited glutathione oxidation. Saline did not alter glutathione status or performance of sustained maneuvers; repetitive task performance was increased by 15% (P < 0.05), a placebo effect. These data indicate that NAC supports glutathione homeostasis in exercising humans and may delay muscle fatigue during repetitive handgrip exercise. Our findings support oxidative stress as a causal factor in human muscle fatigue and argue for larger translational studies to define NAC effects on human performance. C1 Univ Kentucky, Med Ctr, Dept Physiol, Lexington, KY 40536 USA. Baylor Coll Med, Dept Med, Houston, TX 77030 USA. Baylor Coll Med, Dept Med, Houston, TX 77030 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Lockheed Martin, Houston, TX USA. RP Reid, MB (reprint author), Univ Kentucky, Med Ctr, Dept Physiol, 800 Rose St,Room MS-509, Lexington, KY 40536 USA. EM michael.reid@uky.edu FU NHLBI NIH HHS [HL45721] NR 35 TC 76 Z9 79 U1 0 U2 4 PU JOHN WILEY & SONS INC PI HOBOKEN PA 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0148-639X J9 MUSCLE NERVE JI Muscle Nerve PD NOV PY 2005 VL 32 IS 5 BP 633 EP 638 DI 10.1002/mus.20385 PG 6 WC Clinical Neurology; Neurosciences SC Neurosciences & Neurology GA 976TK UT WOS:000232756100009 PM 16025522 ER PT J AU Strus, MC Raman, A Han, CS Nguyen, CV AF Strus, MC Raman, A Han, CS Nguyen, CV TI Imaging artefacts in atomic force microscopy with carbon nanotube tips SO NANOTECHNOLOGY LA English DT Article ID SCANNING PROBE; AFM PROBES; ULTRAVIOLET; RESOLUTION; SILICON; APEX AB Dynamic atomic force microscopy (dynamic AFM) with carbon nanotube tips has been suggested as an enabling tool for high precision nanometrology of critical dimension features of semiconductor surfaces. We investigate the performance of oscillating AFM microcantilevers with multi-walled carbon nanotube (multi-walled CNT) tips interacting with high aspect ratio structures while in the attractive regime of dynamic AM We present experimental results on SiO2 gratings and tungsten nanorods, which show two distinct imaging artefacts, namely the fort-nation of divots and large ringing artefacts that are inherent to CNT AFM probe operation. Through meticulous adjustment of operating parameters, the connection of these artefacts to CNT bending, adhesion, and stiction is described qualitatively and explained. C1 Purdue Univ, Sch Mech Engn, W Lafayette, IN 47907 USA. Korean Inst Machines & Mat, Ctr Nanomech & Mfg, Taejon, South Korea. NASA, Ames Res Ctr, ELORET Corp, Moffett Field, CA 94035 USA. RP Strus, MC (reprint author), Purdue Univ, Sch Mech Engn, W Lafayette, IN 47907 USA. EM raman@ecn.purdue.edu RI Strus, Mark/A-5225-2009 NR 27 TC 42 Z9 42 U1 2 U2 14 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0957-4484 J9 NANOTECHNOLOGY JI Nanotechnology PD NOV PY 2005 VL 16 IS 11 BP 2482 EP 2492 DI 10.1088/0957-4484/16/11/003 PG 11 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied SC Science & Technology - Other Topics; Materials Science; Physics GA 987BX UT WOS:000233494500003 ER PT J AU Stapelfeldt, K Beichman, C Kuchner, M AF Stapelfeldt, K Beichman, C Kuchner, M TI General astrophysics with the optical terrestrial planet finder mission SO NEW ASTRONOMY REVIEWS LA English DT Article; Proceedings Paper CT Conference on Wide-Field Imaging from Space CY MAY 16-18, 2004 CL Lawrence Berkeley Natl Lab, Berkeley, CA HO Lawrence Berkeley Natl Lab AB The Terrestrial Planet Finder (TPF) mission is being designed to directly detect terrestrial planets in the habitable zones around nearby FGK stars, and to spectrally characterize them for the presence of biomarkers. TPF is now planned as two missions: a similar to x 3.5 m optical coronagraphic telescope (TPF-C) to fly circa 2014; and a formation-flying infrared nulling interferometer (TPF-I) to follow several years later. While high contrast performance and planet-finding will remain the primary science drivers for both missions, the project has begun to consider possible extensions to their capabilities that would enable progress in other important areas of astrophysics. For example, deep extragalactic surveys could be enabled by adding a camera with a several arcminute field of view to TPF-C. Here, we give an overview of the TPF-C project, and offer initial suggestions for its application to general astrophysics. (c) 2005 Published by Elsevier B.V. C1 CALTECH, Michelson Sci Ctr, Pasadena, CA 91125 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Princeton Univ, Dept Astrophys, Princeton, NJ 08544 USA. RP Beichman, C (reprint author), CALTECH, Michelson Sci Ctr, Mail Stop 100-22, Pasadena, CA 91125 USA. EM chas@ipac.caltech.edu RI Stapelfeldt, Karl/D-2721-2012; Kuchner, Marc/E-2288-2012 NR 0 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1387-6473 J9 NEW ASTRON REV JI New Astron. Rev. PD NOV PY 2005 VL 49 IS 7-9 BP 396 EP 399 DI 10.1016/j.newar.2005.08.011 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 985NP UT WOS:000233385000011 ER PT J AU Basri, G Borucki, WJ Koch, D AF Basri, G Borucki, WJ Koch, D TI The Kepler Mission: A wide-field transit search for terrestrial planets SO NEW ASTRONOMY REVIEWS LA English DT Article; Proceedings Paper CT Conference on Wide-Field Imaging from Space CY MAY 16-18, 2004 CL Lawrence Berkeley Natl Lab, Berkeley, CA HO Lawrence Berkeley Natl Lab ID EXTRASOLAR GIANT PLANETS; SPECTRA AB The Kepler Mission is a NASA Discovery mission which will continuously monitor the brightness of at least 100,000 main sequence stars, to detect the transits of terrestrial and larger planets. It is scheduled to be launched in 2007 into an Earth-trailing heliocentric orbit. It is a wide-field photometer with a Schmidt-type telescope and array of 42 CCDs covering the 100 square degree field-of-view. It has a 1-m aperture which enables a differential photometric precision of 2 parts in 100,000 for 12th magnitude solar-like stars over a 6.5-hour transit duration. It will continuously observe dwarf stars from 8th to 15th magnitude in the Cygnus constellation, for a period of four years, with a cadence of 4 measurements per hour. Hundreds of terrestrial planets should be detected if they are common around solar-type stars. Ground-based spectrometry of stars with planetary candidates will help eliminate false-positives.. and determine stellar characteristics such as mass and metallicity. A null result would imply that terrestrial planets are rare. (c) 2005 Published by Elsevier B.V. C1 Univ Calif Berkeley, Berkeley, CA 94720 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Basri, G (reprint author), Univ Calif Berkeley, Berkeley, CA 94720 USA. EM basri@astro.berkeley.edu NR 9 TC 92 Z9 92 U1 0 U2 7 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1387-6473 J9 NEW ASTRON REV JI New Astron. Rev. PD NOV PY 2005 VL 49 IS 7-9 BP 478 EP 485 DI 10.1016/j.newar.2005.08.026 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 985NP UT WOS:000233385000026 ER PT J AU Ganel, O Adams, JH Ahn, HS Ampe, J Bashindzhagyan, G Case, G Chang, J Ellison, S Fazely, A Gould, R Granger, D Gunasingha, R Guzik, TG Han, YJ Isbert, J Kim, HJ Kim, KC Kim, SK Kwon, Y Panasyuk, M Panov, A Price, B Samsonov, G Schmidt, WKH Sen, M Seo, ES Sina, R Sokolskaya, N Stewart, M Voronin, A Wagner, D Wang, JZ Wefel, JP Wu, J Zatsepin, V AF Ganel, O Adams, JH Ahn, HS Ampe, J Bashindzhagyan, G Case, G Chang, J Ellison, S Fazely, A Gould, R Granger, D Gunasingha, R Guzik, TG Han, YJ Isbert, J Kim, HJ Kim, KC Kim, SK Kwon, Y Panasyuk, M Panov, A Price, B Samsonov, G Schmidt, WKH Sen, M Seo, ES Sina, R Sokolskaya, N Stewart, M Voronin, A Wagner, D Wang, JZ Wefel, JP Wu, J Zatsepin, V TI Beam tests of the balloon-borne ATIC experiment SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE cosmic-ray calorimeter; High-energy cosmic rays ID THIN IONIZATION CALORIMETER; ENERGY COSMIC-RAYS; SPECTRUM AB The Advanced Thin Ionization Calorimeter (ATIC) balloon-borne experiment is designed to perform cosmic-ray elemental spectra measurements from 50 GeV to 100TeV for nuclei from hydrogen to iron. These measurements are expected to provide information about some of the most fundamental questions in astroparticle physics today. ATIC's design centers on an 18 radiation length (X-0) deep bismuth germanate (BGO) calorimeter, preceded by a 0.75 lambda(int) graphite target. In September 1999, the ATIC detector was exposed to high-energy beams at CERN's SPS accelerator within the framework of the development program for the Advanced Cosmic-ray Composition Experiment for the Space Station (ACCESS). In December 2000-January 2001 and again in December 2002-January 2003, ATIC flew on the first two of a series of long-duration balloon (LDB) flights from McMurdo Station, Antarctica. We present here results from the 1999 beam tests, including energy resolutions for electrons and protons at several beam energies from 100 to 375 GeV as well as signal linearity and collection efficiency estimates. We show how these results compare with expectations based on simulations and their expected impacts on mission performance. (c) 2005 Elsevier B.V. All rights reserved. C1 Univ Maryland, Inst Phys Sci & Technol, College Pk, MD 20742 USA. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. Moscow MV Lomonosov State Univ, Skobeltsyn Inst Nucl Phys, Moscow 119899, Russia. Louisiana State Univ, Dept Phys & Astron, Baton Rouge, LA 70803 USA. Max Planck Inst Aeron, D-37191 Katlenburg Lindau, Germany. So Univ, Dept Phys, Baton Rouge, LA 70813 USA. Seoul Natl Univ, Dept Phys, Seoul 151742, South Korea. Chinese Acad Sci, Purple Mt Observ, Beijing 100864, Peoples R China. RP Ganel, O (reprint author), Univ Maryland, Inst Phys Sci & Technol, College Pk, MD 20742 USA. EM opher@umd.edu RI Panasyuk, Mikhail/E-2005-2012; Panov, Alexander/K-3952-2012; Kim, Sun Kee/G-2042-2015; OI Panov, Alexander/0000-0003-2290-6498; Kim, Sun Kee/0000-0002-0013-0775; Seo, Eun-Suk/0000-0001-8682-805X NR 22 TC 11 Z9 11 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD NOV 1 PY 2005 VL 552 IS 3 BP 409 EP 419 DI 10.1016/j.nima.2005.06.081 PG 11 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 981EL UT WOS:000233070100011 ER PT J AU Wu, F Guo, SP Ikram, K Albin, S Tai, H Rogowski, RS AF Wu, F Guo, SP Ikram, K Albin, S Tai, H Rogowski, RS TI "Numerical analysis of Bragg fibers using a compact 1 D finite-difference frequency-domain method" (vol 249, pg 165, 2005) SO OPTICS COMMUNICATIONS LA English DT Correction C1 Old Dominion Univ, Dept Elect & Comp Engn, Norfolk, VA 23529 USA. NASA, Langley Res Ctr, Nondestruct Evaluat Sci Branch, Hamptonm, VA 23681 USA. RP Wu, F (reprint author), Old Dominion Univ, Dept Elect & Comp Engn, Hampton Blvd, Norfolk, VA 23529 USA. EM fwu@odu.edu NR 1 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0030-4018 J9 OPT COMMUN JI Opt. Commun. PD NOV 1 PY 2005 VL 255 IS 1-3 BP 167 EP 167 DI 10.1016/j.optcom.2005.01.058 PG 1 WC Optics SC Optics GA 974YP UT WOS:000232627600017 ER PT J AU Astafieva, MM Vikers-Rich, P Wilde, A Rozanov, AY Hoover, R AF Astafieva, MM Vikers-Rich, P Wilde, A Rozanov, AY Hoover, R TI Possible biogenic origin of Middle Proterozoic (1.64 Ga) polymetallic ores of the McArthur River Deposit in Northern Australia SO PALEONTOLOGICAL JOURNAL LA English DT Article DE cocci; sulfate-reducing bacteria; cyanobacteria; purple bacteria; sulfides; photic zone ID PYRITE FORMATION; SULFUR AB The study of samples from the McArthur River complex ore deposit (Middle Proterozoic, 1.64 Ga), one of the largest zinc-lead mineral deposits in the world, suggests a possible biogenic origin of sulfides in this deposit and a likelihood that the rocks studied formed in the marine photic zone. C1 Russian Acad Sci, Inst Paleontol, Moscow 117997, Russia. NASA, George C Marshall Space Flight Ctr, Space Sci Lab, Huntsville, AL 35812 USA. Monash Univ, Sch Geosci, Clayton, Vic 3168, Australia. RP Astafieva, MM (reprint author), Russian Acad Sci, Inst Paleontol, Profsoyuznaya Ul 123, Moscow 117997, Russia. EM astafieva@paleo.ru NR 11 TC 0 Z9 0 U1 0 U2 3 PU INTERPERIODICA PI BIRMINGHAM PA PO BOX 1831, BIRMINGHAM, AL 35201-1831 USA SN 0031-0301 J9 PALEONTOL J+ JI Paleontol. J. PD NOV-DEC PY 2005 VL 39 IS 6 BP 577 EP 581 PG 5 WC Paleontology SC Paleontology GA 990PI UT WOS:000233755300001 ER PT J AU Kapale, KT Agarwal, GS Scully, MO AF Kapale, KT Agarwal, GS Scully, MO TI Cavity-mediated long-range interaction for fast multiqubit quantum logic operations SO PHYSICAL REVIEW A LA English DT Article ID ERROR-CORRECTION; SINGLE PHOTONS; TRAPPED IONS; GATES; COMPUTATION; COMPUTER; SCHEME AB Interactions among qubits are essential for performing two-qubit quantum logic operations. However, nature gives us only nearest neighbor interactions in simple and controllable settings. Here we propose a strategy to induce interactions among two atomic entities that are not necessarily neighbors of each other through their common coupling with a cavity field. This facilitates fast multiqubit quantum logic operations through a set of two-qubit operations. Using its explicit position dependence, this interaction can be employed for simulation of quantum spin systems. The ideas presented here are applicable to various quantum-information proposals for atom-based qubits such as trapped ions, atoms trapped in optical cavities, and optical lattices. C1 CALTECH, Jet Prop Lab, Quantum Comp Technol Grp, Pasadena, CA 91109 USA. Oklahoma State Univ, Dept Phys, Stillwater, OK 74078 USA. Texas A&M Univ, Inst Quantum Studies, College Stn, TX 77843 USA. Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA. Princeton Univ, Dept Chem, Princeton, NJ 08544 USA. RP Kapale, KT (reprint author), CALTECH, Jet Prop Lab, Quantum Comp Technol Grp, Mail Stop 126-347,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Kishor.T.Kapale@jpl.nasa.gov NR 30 TC 6 Z9 6 U1 1 U2 2 PU AMERICAN 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 NOV PY 2005 VL 72 IS 5 AR 052304 DI 10.1103/PhysRevA.72.052304 PG 9 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 988LT UT WOS:000233603400043 ER PT J AU Bakunov, MI Maslov, AV Bodrov, SB AF Bakunov, MI Maslov, AV Bodrov, SB TI Cherenkov radiation of terahertz surface plasmon polaritons from a superluminal optical spot SO PHYSICAL REVIEW B LA English DT Article ID TIME-DOMAIN SPECTROSCOPY; SEMICONDUCTOR SURFACES; PULSES; GENERATION; RECTIFICATION; EMISSION; GAAS AB We propose to use a cylindrically focused ultrashort laser pulse obliquely incident on a semiconductor surface to launch surface plasmon polaritons with frequencies in the terahertz range. The laser pulse creates a spot of nonlinear polarization moving along the semiconductor surface with superluminal velocity. We show theoretically that the spot will emit the surface and free-space waves via Cherenkov mechanism. We develop a theory and calculate the radiated fields and frequency distribution of the radiated energy. The efficiency of the optical-to-terahertz conversion is estimated for the case of nonlinear optical rectification in GaAs. We show that one can control the radiation pattern and spectrum of the surface waves by varying the incident angle of the optical beam and crystalline orientation of the semiconductor. This technique opens new ways to build terahertz sources and perform surface spectroscopy. C1 Univ Nizhny Novgorod, Dept Radiophys, Nizhnii Novgorod 603950, Russia. Russian Acad Sci, Inst Appl Phys, Nizhnii Novgorod 603950, Russia. NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. RP Univ Nizhny Novgorod, Dept Radiophys, Nizhnii Novgorod 603950, Russia. RI Schaff, William/B-5839-2009; Maslov, Alexey/E-5158-2011; Bodrov, Sergey/D-1962-2012; Bakunov, Michael/E-2875-2017 OI Maslov, Alexey/0000-0002-7835-2474; Bakunov, Michael/0000-0002-4209-1372 NR 27 TC 26 Z9 27 U1 2 U2 6 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD NOV PY 2005 VL 72 IS 19 AR 195336 DI 10.1103/PhysRevB.72.195336 PG 9 WC Physics, Condensed Matter SC Physics GA 988LW UT WOS:000233603700103 ER PT J AU Lee, GW Gangopadhyay, AK Croat, TK Rathz, TJ Hyers, RW Rogers, JR Kelton, KF AF Lee, GW Gangopadhyay, AK Croat, TK Rathz, TJ Hyers, RW Rogers, JR Kelton, KF TI Link between liquid structure and the nucleation barrier for icosahedral quasicrystal, polytetrahedral, and simple crystalline phases in Ti-Zr-Ni alloys: Verification of Frank's hypothesis SO PHYSICAL REVIEW B LA English DT Article ID GA-MG-ZN; SURFACE-TENSION; METALLIC MELTS; FORMING ALLOYS; FREE-ENERGY; SOLIDIFICATION; INTERFACE; GLASSES; ORDER; APPROXIMATION AB Comprehensive undercooling experiments on a large number of simple crystalline, polytetrahedral, and icosahedral quasicrystalline phase forming compositions in Ti-Zr-Ni alloys have been carried out using electrostatic levitation (ESL) techniques for containerless processing. Consistent with Frank's hypothesis, a direct correlation was found between the reduced undercooling [Delta T-r=(T-l-T-r)/T-l, where T-r and T-l are the nucleation and liquidus temperatures, respectively] and the icosahedral short-range order in the solid. The reduced undercooling is less for liquids that form the icosahedral quasicrystal (i phase) than for those that form the hcp C14 Laves polytetrahedral phase. For many compositions near 21 at. % Ni, the primary nucleation of a metastable i phase instead of a stable C14 Laves phase demonstrates that the interfacial free energy between the liquid and the i phase is smaller than between the liquid and the C14 Laves phase, indicating icosahedral local order in the undercooled liquid. This is in agreement with a classical-nucleation-theory-based estimate of the interfacial free energy and the work of formation of the critical cluster from the undercooling data. Taken together with high-energy x-ray diffraction studies of the undercooled liquid, these results demonstrate that the local structure of liquids in Ti-Zr-Ni alloys is icosahedral, as postulated by Frank over a half century ago. C1 Washington Univ, Dept Phys, St Louis, MO 63130 USA. Washington Univ, Ctr Mat Innovat, St Louis, MO 63130 USA. Univ Alabama, Huntsville, AL 35801 USA. Univ Massachusetts, Amherst, MA 01003 USA. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Lee, GW (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. EM lee210@llnl.gov RI Hyers, Robert/G-3755-2010 NR 42 TC 43 Z9 44 U1 3 U2 16 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 NOV PY 2005 VL 72 IS 17 AR 174107 DI 10.1103/PhysRevB.72.174107 PG 10 WC Physics, Condensed Matter SC Physics GA 988LU UT WOS:000233603500040 ER PT J AU Abbott, B Abbott, R Adhikari, R Ageev, A Agresti, J Allen, B Allen, J Amin, R Anderson, SB Anderson, WG Araya, M Armandula, H Ashley, M Asiri, F Aufmuth, P Aulbert, C Babak, S Balasubramanian, R Ballmer, S Barish, BC Barker, C Barker, D Barnes, M Barr, B Barton, MA Bayer, K Beausoleil, R Belczynski, K Bennett, R Berukoff, SJ Betzwieser, J Bhawal, B Bilenko, IA Billingsley, G Black, E Blackburn, K Blackburn, L Bland, B Bochner, B Bogue, L Bork, R Bose, S Brady, PR Braginsky, VB Brau, JE Brown, DA Bullington, A Bunkowski, A Buonanno, A Burgess, R Busby, D Butler, WE Byer, RL Cadonati, L Cagnoli, G Camp, JB Cannizzo, J Cannon, K Cantley, CA Cardenas, L Carter, K Casey, MM Castiglione, J Chandler, A Chapsky, J Charlton, P Chatterji, S Chelkowski, S Chen, Y Chickarmane, V Chin, D Christensen, N Churches, D Cokelaer, T Colacino, C Coldwell, R Coles, M Cook, D Corbitt, T Coyne, D Creighton, JDE Creighton, TD Crooks, DRM Csatorday, P Cusack, BJ Cutler, C Dalrymple, J D'Ambrosio, E Danzmann, K Davies, G Daw, E DeBra, D Delker, T Dergachev, V Desai, S DeSalvo, R Dhurandhar, S Credico, AD Diaz, M Ding, H Drever, RWP Dupuis, RJ Edlund, JA Ehrens, P Elliffe, EJ Etzel, T Evans, M Evans, T Fairhurst, S Fallnich, C Farnham, D Fejer, MM Findley, T Fine, M Finn, LS Franzen, KY Freise, A Frey, R Fritschel, P Frolov, VV Fyffe, M Ganezer, KS Garofoli, J Giaime, JA Gillespie, A Goda, K Goggin, L Gonzalez, G Gossler, S Grandclement, P Grant, A Gray, C Gretarsson, AM Grimmett, D Grote, H Grunewald, S Guenther, M Gustafson, E Gustafson, R Hamilton, WO Hammond, M Hanson, J Hardham, C Harms, J Harry, G Hartunian, A Heefner, J Hefetz, Y Heinzel, G Heng, IS Hennessy, M Hepler, N Heptonstall, A Heurs, M Hewitson, M Hild, S Hindman, N Hoang, P Hough, J Hrynevych, M Hua, W Ito, M Itoh, Y Ivanov, A Jennrich, O Johnson, B Johnson, WW Johnston, WR Jones, DI Jones, G Jones, L Jungwirth, D Kalogera, V Katsavounidis, E Kawabe, K Kawamura, S Kells, W Kern, J Khan, A Killbourn, S Killow, CJ Kim, C King, C King, P Klimenko, S Koranda, S Kotter, K Kovalik, J Kozak, D Krishnan, B Landry, M Langdale, J Lantz, B Lawrence, R Lazzarini, A Lei, M Leonor, I Libbrecht, K Libson, A Lindquist, P Liu, S Logan, J Lormand, M Lubinski, M Luck, H Luna, M Lyons, TT Machenschalk, B MacInnis, M Mageswaran, M Mailand, K Majid, W Malec, M Mandic, V Mann, F Marin, A Marka, S Maros, E Mason, J Mason, K Matherny, O Matone, L Mavalvala, N McCarthy, R McClelland, DE McHugh, M McNabb, JWC Melissinos, A Mendell, G Mercer, RA Meshkov, S Messaritaki, E Messenger, C Mikhailov, E Mitra, S Mitrofanov, VP Mitselmakher, G Mittleman, R Miyakawa, O Miyoki, S Mohanty, S Moreno, G Mossavi, K Mueller, G Mukherjee, S Murray, P Myers, E Myers, J Nagano, S Nash, T Nayak, R Newton, G Nocera, F Noel, JS Nutzman, P Olson, T O'Reilly, B Ottaway, DJ Ottewill, A Ouimette, D Overmier, H Owen, BJ Pan, Y Papa, MA Parameshwaraiah, V Parameswaran, A Parameswariah, C Pedraza, M Penn, S Pitkin, M Plissi, M Prix, R Quetschke, V Raab, F Radkins, H Rahkola, R Rakhmanov, M Rao, SR Rawlins, K Ray-Majumder, S Re, V Redding, D Regehr, MW Regimbau, T Reid, S Reilly, KT Reithmaier, K Reitze, DH Richman, S Riesen, R Riles, K Rivera, B Rizzi, A Robertson, DI Robertson, NA Robinson, C Robison, L Roddy, S Rodriguez, A Rollins, J Romano, JD Romie, J Rong, H Rose, D Rotthoff, E Rowan, S Rudiger, A Ruet, L Russell, P Ryan, K Salzman, I Sandberg, V Sanders, GH Sannibale, V Sarin, P Sathyaprakash, B Saulson, PR Savage, R Sazonov, A Schilling, R Schlaufman, K Schmidt, V Schnabel, R Schofield, R Schutz, BF Schwinberg, P Scott, SM Seader, SE Searle, AC Sears, B Seel, S Seifert, F Sellers, D Sengupta, AS Shapiro, CA Shawhan, P Shoemaker, DH Shu, QZ Sibley, A Siemens, X Sievers, L Sigg, D Sintes, AM Smith, JR Smith, M Smith, MR Sneddon, PH Spero, R Spjeld, O Stapfer, G Steussy, D Strain, KA Strom, D Stuver, A Summerscales, T Sumner, MC Sung, M Sutton, PJ Sylvestre, J Takamori, A Tanner, DB Tariq, H Taylor, I Taylor, R Taylor, R Thorne, KA Thorne, KS Tibbits, M Tilav, S Tinto, M Tokmakov, KV Torres, C Torrie, C Traylor, G Tyler, W Ugolini, D Ungarelli, C Vallisneri, M van Putten, M Vass, S Vecchio, A Veitch, J Vorvick, C Vyachanin, SP Wallace, L Walther, H Ward, H Ward, R Ware, B Watts, K Webber, D Weidner, A Weiland, U Weinstein, A Weiss, R Welling, H Wen, L Wen, S Wette, K Whelan, JT Whitcomb, SE Whiting, BF Wiley, S Wilkinson, C Willems, PA Williams, PR Williams, R Willke, B Wilson, A Winjum, BJ Winkler, W Wise, S Wiseman, AG Woan, G Woods, D Wooley, R Worden, J Wu, W Yakushin, I Yamamoto, H Yoshida, S Zaleski, KD Zanolin, M Zawischa, I Zhang, L Zhu, R Zotov, N Zucker, M Zweizig, J AF Abbott, B Abbott, R Adhikari, R Ageev, A Agresti, J Allen, B Allen, J Amin, R Anderson, SB Anderson, WG Araya, M Armandula, H Ashley, M Asiri, F Aufmuth, P Aulbert, C Babak, S Balasubramanian, R Ballmer, S Barish, BC Barker, C Barker, D Barnes, M Barr, B Barton, MA Bayer, K Beausoleil, R Belczynski, K Bennett, R Berukoff, SJ Betzwieser, J Bhawal, B Bilenko, IA Billingsley, G Black, E Blackburn, K Blackburn, L Bland, B Bochner, B Bogue, L Bork, R Bose, S Brady, PR Braginsky, VB Brau, JE Brown, DA Bullington, A Bunkowski, A Buonanno, A Burgess, R Busby, D Butler, WE Byer, RL Cadonati, L Cagnoli, G Camp, JB Cannizzo, J Cannon, K Cantley, CA Cardenas, L Carter, K Casey, MM Castiglione, J Chandler, A Chapsky, J Charlton, P Chatterji, S Chelkowski, S Chen, Y Chickarmane, V Chin, D Christensen, N Churches, D Cokelaer, T Colacino, C Coldwell, R Coles, M Cook, D Corbitt, T Coyne, D Creighton, JDE Creighton, TD Crooks, DRM Csatorday, P Cusack, BJ Cutler, C Dalrymple, J D'Ambrosio, E Danzmann, K Davies, G Daw, E DeBra, D Delker, T Dergachev, V Desai, S DeSalvo, R Dhurandhar, S Credico, AD Diaz, M Ding, H Drever, RWP Dupuis, RJ Edlund, JA Ehrens, P Elliffe, EJ Etzel, T Evans, M Evans, T Fairhurst, S Fallnich, C Farnham, D Fejer, MM Findley, T Fine, M Finn, LS Franzen, KY Freise, A Frey, R Fritschel, P Frolov, VV Fyffe, M Ganezer, KS Garofoli, J Giaime, JA Gillespie, A Goda, K Goggin, L Gonzalez, G Gossler, S Grandclement, P Grant, A Gray, C Gretarsson, AM Grimmett, D Grote, H Grunewald, S Guenther, M Gustafson, E Gustafson, R Hamilton, WO Hammond, M Hanson, J Hardham, C Harms, J Harry, G Hartunian, A Heefner, J Hefetz, Y Heinzel, G Heng, IS Hennessy, M Hepler, N Heptonstall, A Heurs, M Hewitson, M Hild, S Hindman, N Hoang, P Hough, J Hrynevych, M Hua, W Ito, M Itoh, Y Ivanov, A Jennrich, O Johnson, B Johnson, WW Johnston, WR Jones, DI Jones, G Jones, L Jungwirth, D Kalogera, V Katsavounidis, E Kawabe, K Kawamura, S Kells, W Kern, J Khan, A Killbourn, S Killow, CJ Kim, C King, C King, P Klimenko, S Koranda, S Kotter, K Kovalik, J Kozak, D Krishnan, B Landry, M Langdale, J Lantz, B Lawrence, R Lazzarini, A Lei, M Leonor, I Libbrecht, K Libson, A Lindquist, P Liu, S Logan, J Lormand, M Lubinski, M Luck, H Luna, M Lyons, TT Machenschalk, B MacInnis, M Mageswaran, M Mailand, K Majid, W Malec, M Mandic, V Mann, F Marin, A Marka, S Maros, E Mason, J Mason, K Matherny, O Matone, L Mavalvala, N McCarthy, R McClelland, DE McHugh, M McNabb, JWC Melissinos, A Mendell, G Mercer, RA Meshkov, S Messaritaki, E Messenger, C Mikhailov, E Mitra, S Mitrofanov, VP Mitselmakher, G Mittleman, R Miyakawa, O Miyoki, S Mohanty, S Moreno, G Mossavi, K Mueller, G Mukherjee, S Murray, P Myers, E Myers, J Nagano, S Nash, T Nayak, R Newton, G Nocera, F Noel, JS Nutzman, P Olson, T O'Reilly, B Ottaway, DJ Ottewill, A Ouimette, D Overmier, H Owen, BJ Pan, Y Papa, MA Parameshwaraiah, V Parameswaran, A Parameswariah, C Pedraza, M Penn, S Pitkin, M Plissi, M Prix, R Quetschke, V Raab, F Radkins, H Rahkola, R Rakhmanov, M Rao, SR Rawlins, K Ray-Majumder, S Re, V Redding, D Regehr, MW Regimbau, T Reid, S Reilly, KT Reithmaier, K Reitze, DH Richman, S Riesen, R Riles, K Rivera, B Rizzi, A Robertson, DI Robertson, NA Robinson, C Robison, L Roddy, S Rodriguez, A Rollins, J Romano, JD Romie, J Rong, H Rose, D Rotthoff, E Rowan, S Rudiger, A Ruet, L Russell, P Ryan, K Salzman, I Sandberg, V Sanders, GH Sannibale, V Sarin, P Sathyaprakash, B Saulson, PR Savage, R Sazonov, A Schilling, R Schlaufman, K Schmidt, V Schnabel, R Schofield, R Schutz, BF Schwinberg, P Scott, SM Seader, SE Searle, AC Sears, B Seel, S Seifert, F Sellers, D Sengupta, AS Shapiro, CA Shawhan, P Shoemaker, DH Shu, QZ Sibley, A Siemens, X Sievers, L Sigg, D Sintes, AM Smith, JR Smith, M Smith, MR Sneddon, PH Spero, R Spjeld, O Stapfer, G Steussy, D Strain, KA Strom, D Stuver, A Summerscales, T Sumner, MC Sung, M Sutton, PJ Sylvestre, J Takamori, A Tanner, DB Tariq, H Taylor, I Taylor, R Taylor, R Thorne, KA Thorne, KS Tibbits, M Tilav, S Tinto, M Tokmakov, KV Torres, C Torrie, C Traylor, G Tyler, W Ugolini, D Ungarelli, C Vallisneri, M van Putten, M Vass, S Vecchio, A Veitch, J Vorvick, C Vyachanin, SP Wallace, L Walther, H Ward, H Ward, R Ware, B Watts, K Webber, D Weidner, A Weiland, U Weinstein, A Weiss, R Welling, H Wen, L Wen, S Wette, K Whelan, JT Whitcomb, SE Whiting, BF Wiley, S Wilkinson, C Willems, PA Williams, PR Williams, R Willke, B Wilson, A Winjum, BJ Winkler, W Wise, S Wiseman, AG Woan, G Woods, D Wooley, R Worden, J Wu, W Yakushin, I Yamamoto, H Yoshida, S Zaleski, KD Zanolin, M Zawischa, I Zhang, L Zhu, R Zotov, N Zucker, M Zweizig, J CA LIGO Sci Collaboration TI First all-sky upper limits from LIGO on the strength of periodic gravitational waves using the Hough transform SO PHYSICAL REVIEW D LA English DT Article ID PRECESSING NEUTRON-STARS; DETECTOR; INTERFEROMETER; EMISSION; GEO-600; SEARCH AB We perform a wide parameter-space search for continuous gravitational waves over the whole sky and over a large range of values of the frequency and the first spin-down parameter. Our search method is based on the Hough transform, which is a semicoherent, computationally efficient, and robust pattern recognition technique. We apply this technique to data from the second science run of the LIGO detectors and our final results are all-sky upper limits on the strength of gravitational waves emitted by unknown isolated spinning neutron stars on a set of narrow frequency bands in the range 200-400 Hz. The best upper limit on the gravitational-wave strain amplitude that we obtain in this frequency range is 4.43x10(-23). C1 Max Planck Inst Gravitat Phys, Albert Einstein Inst, D-14476 Golm, Germany. Max Planck Inst Gravitat Phys, Albert Einstein Inst, D-30167 Hannover, Germany. Australian Natl Univ, Canberra, ACT 0200, Australia. CALTECH, Pasadena, CA 91125 USA. Calif State Univ Dominguez Hills, Carson, CA 90747 USA. CALTECH, CaRT, Pasadena, CA 91125 USA. Cardiff Univ, Cardiff CF2 3YB, Wales. Carleton Coll, Northfield, MN 55057 USA. Columbia Univ, New York, NY 10027 USA. Hobart & William Smith Coll, Geneva, NY 14456 USA. Interuniv Ctr Astron & Astrophys, Pune 411007, Maharashtra, India. CALTECH, LIGO, Pasadena, CA 91125 USA. MIT, LIGO, Cambridge, MA 02139 USA. Hanford Observ, LIGO, Richland, WA 99352 USA. Livingston Observ, LIGO, Livingston, LA 70754 USA. Louisiana State Univ, Baton Rouge, LA 70803 USA. Louisiana Tech Univ, Ruston, LA 71272 USA. Loyola Univ, New Orleans, LA 70118 USA. Max Planck Inst Quantum Opt, D-85748 Garching, Germany. Moscow MV Lomonosov State Univ, Moscow 119992, Russia. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Natl Astron Observ, Tokyo 1818588, Japan. Northwestern Univ, Evanston, IL 60208 USA. Salish Kootenai Coll, Pablo, MT 59855 USA. SE Louisiana Univ, Hammond, LA 70402 USA. Stanford Univ, Stanford, CA 94305 USA. Syracuse Univ, Syracuse, NY 13244 USA. Penn State Univ, University Pk, PA 16802 USA. Univ Texas, Brownsville, TX 78520 USA. Texas Southmost Coll, Brownsville, TX 78520 USA. Trinity Univ, San Antonio, TX 78212 USA. Leibniz Univ Hannover, D-30167 Hannover, Germany. Univ Illes Balears, E-07122 Palma de Mallorca, Spain. Univ Birmingham, Birmingham B15 2TT, W Midlands, England. Univ Florida, Gainesville, FL 32611 USA. Univ Glasgow, Glasgow G12 8QQ, Lanark, Scotland. Univ Michigan, Ann Arbor, MI 48109 USA. Univ Oregon, Eugene, OR 97403 USA. Univ Rochester, Rochester, NY 14627 USA. Univ Wisconsin, Milwaukee, WI 53201 USA. Vassar Coll, Poughkeepsie, NY 12604 USA. Washington State Univ, Pullman, WA 99164 USA. RP Max Planck Inst Gravitat Phys, Albert Einstein Inst, D-14476 Golm, Germany. RI Raab, Frederick/E-2222-2011; Rowan, Sheila/E-3032-2010; Lueck, Harald/F-7100-2011; Freise, Andreas/F-8892-2011; Kawabe, Keita/G-9840-2011; Ottewill, Adrian/A-1838-2016; Frey, Raymond/E-2830-2016; Barker, David/A-5671-2013; Mitrofanov, Valery/D-8501-2012; Finn, Lee Samuel/A-3452-2009; Messaritaki, Eirini/D-7393-2016; Liu, Sheng/K-2815-2013; Pitkin, Matthew/I-3802-2013; Vyatchanin, Sergey/J-2238-2012; Chen, Yanbei/A-2604-2013; Bilenko, Igor/D-5172-2012; Harms, Jan/J-4359-2012; Agresti, Juri/G-8168-2012; Sylvestre, Julien/A-8610-2009; Casey, Morag/C-9703-2010; Sigg, Daniel/I-4308-2015; van Putten, Maurice/F-5237-2011; Beausoleil, Raymond/C-5076-2009; Allen, Bruce/K-2327-2012; Hild, Stefan/A-3864-2010; McClelland, David/E-6765-2010; Vecchio, Alberto/F-8310-2015; Strain, Kenneth/D-5236-2011; Ottaway, David/J-5908-2015; Schutz, Bernard/B-1504-2010 OI Zweizig, John/0000-0002-1521-3397; Russell, Pamela/0000-0002-3995-1239; Fairhurst, Stephen/0000-0001-8480-1961; Taylor, Ian/0000-0001-5040-0772; Freise, Andreas/0000-0001-6586-9901; Whiting, Bernard F/0000-0002-8501-8669; Lueck, Harald/0000-0001-9350-4846; Ottewill, Adrian/0000-0003-3293-8450; Frey, Raymond/0000-0003-0341-2636; Whelan, John/0000-0001-5710-6576; Stuver, Amber/0000-0003-0324-5735; Finn, Lee Samuel/0000-0002-3937-0688; Pitkin, Matthew/0000-0003-4548-526X; Agresti, Juri/0000-0001-6119-2470; Sylvestre, Julien/0000-0001-8136-4348; Sigg, Daniel/0000-0003-4606-6526; Allen, Bruce/0000-0003-4285-6256; McClelland, David/0000-0001-6210-5842; Vecchio, Alberto/0000-0002-6254-1617; Strain, Kenneth/0000-0002-2066-5355; NR 49 TC 146 Z9 145 U1 3 U2 10 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 NOV PY 2005 VL 72 IS 10 AR 102004 DI 10.1103/PhysRevD.72.102004 PG 22 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 988NV UT WOS:000233608800007 ER PT J AU Baker, JG van Meter, JR AF Baker, JG van Meter, JR TI Reducing reflections from mesh refinement interfaces in numerical relativity SO PHYSICAL REVIEW D LA English DT Article ID GRAVITATIONAL-WAVES; EVOLUTIONS AB Full interpretation of data from gravitational wave observations will require accurate numerical simulations of source systems, particularly binary black hole mergers. A leading approach to improving accuracy in numerical relativity simulations of black hole systems is through fixed or adaptive mesh refinement techniques. We describe a manifestation of numerical interface truncation error which appears as significant, artificial reflections from refinement boundaries in a broad class of mesh refinement implementations, potentially compromising the effectiveness of mesh refinement techniques for some numerical relativity applications (if left untreated). We elucidate this numerical effect by presenting a model problem which exhibits the phenomenon, but which is simple enough that its numerical error can be understood analytically. Our analysis shows that the effect is caused by variations in finite differencing error generated across low and high resolution regions, and that associated difficulties in demonstrating convergence at modest resolutions are caused by the presence of dramatic speed differences among propagation modes typical of 3+1 relativity. Last, to further verify our understanding of this problem, we present a class of finite differencing stencils of the same order of accuracy as the desired order of convergence, termed mesh-adapted differencing (MAD), which eliminate this pathology in both our model problem and in numerical relativity examples. C1 NASA, Goddard Space Flight Ctr, Lab Gravitat Astrophys, Greenbelt, MD 20771 USA. RP Baker, JG (reprint author), NASA, Goddard Space Flight Ctr, Lab Gravitat Astrophys, Greenbelt, MD 20771 USA. RI van meter, james/E-7893-2011 NR 21 TC 9 Z9 9 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1550-7998 J9 PHYS REV D JI Phys. Rev. D PD NOV PY 2005 VL 72 IS 10 AR 104010 DI 10.1103/PhysRevD.72.104010 PG 8 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 988NV UT WOS:000233608800052 ER PT J AU Bertone, G Merritt, D AF Bertone, G Merritt, D TI Time-dependent models for dark matter at the galactic center SO PHYSICAL REVIEW D LA English DT Article ID SUPERMASSIVE BLACK-HOLE; GAMMA-RAYS; DENSITY PROFILES; HALOS; SUPERSYMMETRY; CONTRACTION; CLUSTER; GALAXY; LIMITS; CUSP AB The prospects for indirect detection of dark matter at the galactic center with gamma-ray experiments like the space telescope GLAST, and air Cherenkov telescopes like HESS, CANGAROO, MAGIC and VERITAS depend sensitively on the mass profile within the inner parsec. We calculate the distribution of dark matter on subparsec scales by integrating the time-dependent Fokker-Planck equation, including the effects of self-annihilations, scattering of dark matter particles by stars, and capture in the supermassive black hole. We consider a variety of initial dark matter distributions, including models with very high densities ("spikes") near the black hole, and models with "adiabatic compression" of the baryons. The annihilation signal after 10(10) yr is found to be substantially reduced from its initial value, but in dark matter models with an initial spike, order-of-magnitude enhancements can persist compared with the rate in spike-free models. C1 NASA, Fermilab Theoret Astrophys Grp, Batavia, IL 60510 USA. Rochester Inst Technol, Dept Phys, Rochester, NY 14623 USA. RP NASA, Fermilab Theoret Astrophys Grp, POB 500, Batavia, IL 60510 USA. NR 41 TC 88 Z9 88 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 NOV PY 2005 VL 72 IS 10 AR 103502 DI 10.1103/PhysRevD.72.103502 PG 6 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 988NV UT WOS:000233608800018 ER PT J AU Stecker, FW AF Stecker, FW TI Note on high-energy neutrinos from active galactic nuclei cores SO PHYSICAL REVIEW D LA English DT Article AB Taking account of new physics and astronomy developments I give a revised high-energy neutrino flux for the active galactic nuclei core model of Stecker, Done, Salamon and Sommers. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Stecker, FW (reprint author), NASA, Goddard Space Flight Ctr, Code 661, Greenbelt, MD 20771 USA. RI Stecker, Floyd/D-3169-2012 NR 11 TC 91 Z9 91 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1550-7998 J9 PHYS REV D JI Phys. Rev. D PD NOV PY 2005 VL 72 IS 10 AR 107301 DI 10.1103/PhysRevD.72.107301 PG 2 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 988NV UT WOS:000233608800095 ER PT J AU LaMarca, HL Ott, CM Bentrup, KHZ LeBlanc, CL Pierson, DL Nelson, AB Scandurro, AB Whitley, GSJ Nickerson, CA Morris, CA AF LaMarca, HL Ott, CM Bentrup, KHZ LeBlanc, CL Pierson, DL Nelson, AB Scandurro, AB Whitley, GSJ Nickerson, CA Morris, CA TI Three-dimensional growth of extravillous cytotrophoblasts promotes differentiation and invasion SO PLACENTA LA English DT Article DE rotating wall vessel; three-dimensional; cytotrophoblast; pregnancy; placentation; differentiation; invasion; matrix metalloproteinase ID TROPHOBLAST CELL-LINES; WORKSHOP REPORT; CULTURE MODELS; ENDOVASCULAR INVASION; ADHESION RECEPTORS; IV COLLAGENASE; NITRIC-OXIDE; IN-VITRO; MATRIX; EXPRESSION AB Human trophoblast research relies on a combination of in vitro models, including isolated primary cultures, explant cultures, and trophoblast cell lines. In the present study, we have utilized the rotating wall vessel (RWV) bioreactor to generate a threedimensional (3-D) model of human placentation for the study of cytotrophoblast (CTB) invasion. The RWV supported the growth of the human CTB cell line SGHPL-4 and allowed for the formation of complex, multilayered 3-D aggregates that were morphologically, phenotypically, and functionally distinct from SGHPL-4 monolayers. The cells cultured three-dimensionally differentiated into an aggressively invasive cell population characterized by the upregulation of matrix metalloproteinase-2 (MMP2), MMP-3, MMP-9 and urokinase-type plasminogen activator (uPA) secretion and activation. Microarray analysis of the 3-D and 2-D cultured cells revealed increased expression in the 3-D cells of various genes that are known mediators of invasion, including MTI-MMP, PECAM-1 and L-selectin, as well as genes not previously associated with CTB differentiation such as MMP-13 and MT5-MMP. These results were verified by quantitative real-time PCR. These findings suggest that when cultured in 3-D, SGHPL-4 cells closely mimic differentiating in utero CTBs, providing a novel approach for the in vitro study of the molecular mechanisms that regulate CTB differentiation and invasion. C1 Tulane Univ, Hlth Sci Ctr, Dept Microbiol & Immunol, New Orleans, LA 70112 USA. Tulane Univ, Hlth Sci Ctr, Interdisciplinary Program Mol & Cellular Biol, New Orleans, LA 70112 USA. Tulane Univ, Hlth Sci Ctr, Tulane Ctr Excellence Bioengn, New Orleans, LA 70112 USA. EASI Wyle Labs, Houston, TX USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. St George Hosp, Sch Med, Dept Biochem & Immunol, London SW17 0RE, England. RP Morris, CA (reprint author), Tulane Univ, Hlth Sci Ctr, Dept Microbiol & Immunol, 1430 Tulane Ave,SL-38, New Orleans, LA 70112 USA. EM cmorris2@tulane.edu FU NICHD NIH HHS [R03 HD045768] NR 47 TC 39 Z9 40 U1 0 U2 1 PU W B SAUNDERS CO LTD PI LONDON PA 32 JAMESTOWN RD, LONDON NW1 7BY, ENGLAND SN 0143-4004 J9 PLACENTA JI Placenta PD NOV PY 2005 VL 26 IS 10 BP 709 EP 720 DI 10.1016/j.placenta.2004.11.003 PG 12 WC Developmental Biology; Obstetrics & Gynecology; Reproductive Biology SC Developmental Biology; Obstetrics & Gynecology; Reproductive Biology GA 977OJ UT WOS:000232812800002 PM 16226120 ER PT J AU Quinn, RC Zent, AP Grunthaner, FJ Ehrenfreund, P Taylor, CL Garry, JRC AF Quinn, RC Zent, AP Grunthaner, FJ Ehrenfreund, P Taylor, CL Garry, JRC TI Detection and characterization of oxidizing acids in the Atacama Desert using the Mars Oxidation Instrument SO PLANETARY AND SPACE SCIENCE LA English DT Article DE Mars instrument; oxidant; acid deposition; Atacama Desert ID MARTIAN SOIL; NITRATE DEPOSITS; ATMOSPHERE; SURFACE; CHILE; LIFE; REACTIVITY; CHEMISTRY; PEROXIDE AB We have performed field experiments to further develop and validate the Mars Oxidation Instrument (MOI) as well as measurement strategies for the in situ characterization of oxidation mechanisms, kinetics, and carbon cycling on Mars. Using the Atacama Desert as a test site for the current dry conditions on Mars, we characterized the chemical reactivity of surface and near-surface atmosphere in the dry core of the Atacama. MOI is a chemiresistor-based sensor array that measures the reaction rates of chemical films that are sensitive to particular types of oxidants or that mimic chemical characteristics of pre-biotic and biotic materials. With these sensors, the chemical reactivity of a planetary environment is characterized by monitoring the resistance of the film as a function of time. Our instrumental approach correlates reaction rates with dust abundance, UV flux, humidity, and temperature, allowing discrimination between competing hypotheses of oxidant formation and organic decomposition. The sensor responses in the Atacama are consistent with an oxidative attack by strong acids triggered by dust accumulation, followed by transient wetting due to an increase in relative humidity during the night. We conclude that in the Atacama Desert, and perhaps on Mars, low pH resulting from acid accumulation, combined with limited water availability and high oxidation potential, can result in oxidizing acid reactions on dust and soil surfaces during low-moisture transient wetting events (i.e. thin films of water). These soil acids are expected to play a significant role in the oxidizing nature of the soils, the formation of mineral surface coatings, and the chemical modification of organics in the surface material. (c) 2005 Published by Elsevier Ltd. C1 NASA, Ames Res Ctr, SETI Inst, Moffett Field, CA 94035 USA. NASA, Jet Prop Lab, In Situ Explorat Technol Grp, Pasadena, CA 91109 USA. Leiden Univ, Leiden Inst Chem, Astrobiol Grp, NL-2300 RA Leiden, Netherlands. RP Quinn, RC (reprint author), NASA, Ames Res Ctr, SETI Inst, Mail Stop 239-12, Moffett Field, CA 94035 USA. EM rquinn@mail.arc.nasa.gov NR 38 TC 44 Z9 45 U1 0 U2 8 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 NOV PY 2005 VL 53 IS 13 BP 1376 EP 1388 DI 10.1016/j.pss.2005.07.004 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 980BR UT WOS:000232989400006 ER PT J AU Stone, RB Tumer, IY Stock, ME AF Stone, RB Tumer, IY Stock, ME TI Linking product functionality to historic failures to improve failure analysis in design SO RESEARCH IN ENGINEERING DESIGN LA English DT Article DE failure analysis; conceptual design; functional modeling; failure modes ID MODE AB Prior research has shown that similar failure modes occur within products (or components) with similar functionality. To capitalize on this finding, a knowledge base-driven failure analysis tool, the function-failure design method (FFDM), has been developed to allow designers to perform failure mode and effect analysis (FMEA) during conceptual design. The FFDM can offer substantial improvements to the design process since it enhances failure analysis thus giving it the ability to reduce the number of necessary redesigns. The FFDM, however, is only as good as the knowledge base that it draws from, and one fundamental question that arises in using the FFDM is: at what level of detail should functional descriptions of components be encoded? This paper explores two approaches to populating a knowledge base with actual failure occurrence information from Bell 206 helicopters. Results indicate that encoding failure data using more detailed functional models allows for a more robust knowledge base. Interestingly however, when applying FFDM, high level descriptions continue to produce useful results when using the knowledge base generated from the detailed functional models. C1 Univ Missouri, Dept Interdisciplinary Design Engn, Rolla, MO 65409 USA. NASA, Computat Sci Div, Ames Res Ctr, Moffett Field, CA 94035 USA. Univ Missouri, Dept Mech Engn, Rolla, MO 65409 USA. RP Stone, RB (reprint author), Univ Missouri, Dept Interdisciplinary Design Engn, 102A Basic Engn Bldg, Rolla, MO 65409 USA. EM rstone@umr.edu; itumer@mail.arc.nasa.gov NR 26 TC 37 Z9 39 U1 1 U2 3 PU SPRINGER HEIDELBERG PI HEIDELBERG PA TIERGARTENSTRASSE 17, D-69121 HEIDELBERG, GERMANY SN 0934-9839 J9 RES ENG DES JI Res. Eng. Design PD NOV PY 2005 VL 16 IS 1-2 BP 96 EP 108 DI 10.1007/s00163-005-0005-z PG 13 WC Engineering, Multidisciplinary; Engineering, Industrial; Engineering, Manufacturing SC Engineering GA 979ZZ UT WOS:000232985000008 ER PT J AU Warmflash, D Weiss, B AF Warmflash, D Weiss, B TI Did life come from another world? SO SCIENTIFIC AMERICAN LA English DT Article AB Developments over the past decade have given new credibility to the idea that Earth's biosphere could have arisen from an extraterrestrial seed. New research indicates that microorganisms could have survived a journey from Mars to Earth. C1 Univ Houston, Houston, TX 77004 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. MIT, Cambridge, MA 02139 USA. RP Warmflash, D (reprint author), Univ Houston, Houston, TX 77004 USA. NR 5 TC 4 Z9 4 U1 0 U2 4 PU SCI AMERICAN INC PI NEW YORK PA 415 MADISON AVE, NEW YORK, NY 10017 USA SN 0036-8733 J9 SCI AM JI Sci.Am. PD NOV PY 2005 VL 293 IS 5 BP 64 EP 71 PG 8 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 974YC UT WOS:000232626300029 PM 16318028 ER PT J AU Jones, JB AF Jones, JB TI How does the slingshot effect work to change the orbit of a spacecraft? SO SCIENTIFIC AMERICAN LA English DT Letter C1 CALTECH, Jet Prop Lab, Pasadena, CA USA. RP Jones, JB (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SCI AMERICAN INC PI NEW YORK PA 415 MADISON AVE, NEW YORK, NY 10017 USA SN 0036-8733 J9 SCI AM JI Sci.Am. PD NOV PY 2005 VL 293 IS 5 BP 116 EP 116 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 974YC UT WOS:000232626300037 ER PT J AU Sullivan, DG Shaw, JN Rickman, D AF Sullivan, DG Shaw, JN Rickman, D TI IKONOS imagery to estimate surface soil property variability in two Alabama physiographies SO SOIL SCIENCE SOCIETY OF AMERICA JOURNAL LA English DT Article ID SPECTRAL REFLECTANCE PROPERTIES; ORGANIC-MATTER; PARTICLE-SIZE; FIELD; PREDICTION; DELINEATION; MINERALOGY; CREATION AB Knowledge of surface soil properties is used to assess past erosion and predict erodibility, determine nutrient requirements, and assess surface texture for soil survey applications. This study was designed to evaluate high resolution IKONOS multispectral data as a soil-mapping tool. Imagery was acquired over conventionally tilled fields in the Coastal Plain and Tennessee Valley physiographic regions of Alabama. Acquisitions were designed to assess the impact of surface crusting, roughness, and tillage on our ability to depict soil property variability. Soils consisted mostly of fine-loamy, kaolinitic, thermic Plinthic Kandiudults at the Coastal Plain site and fine, kaolinitic, thermic Rhodic Paleudults at the Tennessee Valley site. Soils were sampled in 0.20-ha grids to a depth of 15 cm and analyzed for percentages of sand (0.05-2 mm), silt (0.002-0.05 mm), clay (<0.002 mm), citrate-dithionite extractable Fe, and total C (TC). Four methods of evaluating variability in soil attributes were evaluated: (i) kriging of soil attributes, (ii) cokriging with soil attributes and reflectance data, (iii) multivariate regression based on the relationship between reflectance and soil properties, and (iv) fuzzy c-means clustering of reflectance data. Results indicate that cokriging with remotely sensed (RS) data improved field scale estimates of surface TC and clay content compared with kriging and regression methods. Fuzzy c-means worked best using remotely sensed data acquired over freshly tilled fields, reducing soil property variability within soil zones compared with field scale soil property variability. C1 USDA ARS, SE Watershed Res Lab, Tifton, GA 31794 USA. Auburn Univ, Dept Agron & Soils, Auburn, AL 36849 USA. NASA, Global Hydrol & Climate Ctr, NSSTC, MSFC, Huntsville, AL 35805 USA. RP Sullivan, DG (reprint author), USDA ARS, SE Watershed Res Lab, POB 748, Tifton, GA 31794 USA. EM dgs@tifton.usda.gov OI Rickman, Doug/0000-0003-3409-2882 NR 35 TC 41 Z9 47 U1 1 U2 16 PU SOIL SCI SOC AMER PI MADISON PA 677 SOUTH SEGOE ROAD, MADISON, WI 53711 USA SN 0361-5995 J9 SOIL SCI SOC AM J JI Soil Sci. Soc. Am. J. PD NOV-DEC PY 2005 VL 69 IS 6 BP 1789 EP 1798 DI 10.2136/sssaj2005.0071 PG 10 WC Soil Science SC Agriculture GA 983HZ UT WOS:000233223500014 ER PT J AU Kasparova, J Karlicky, M Kontar, EP Schwartz, RA Dennis, BR AF Kasparova, J Karlicky, M Kontar, EP Schwartz, RA Dennis, BR TI Multi-wavelength analysis of high-energy electrons in solar flares: A case study of the August 20,2002 flare SO SOLAR PHYSICS LA English DT Article ID X-RAY-SPECTRA; FLUX SPECTRA; RHESSI DATA; BURSTS; DISTRIBUTIONS; MODELS; CORONA; PHASE; BEAMS AB A multi-wavelength spatial and temporal analysis of solar high-energy electrons is conducted using the August 20, 2002 flare of ail unusually flat (gamma(1) = 1.8) hard X-ray spectrum. The flare is studied using RHESSI, H alpha, radio, TRACE, and MDI observations with advanced methods and techniques never previously applied in the solar flare context. A new method to account for X-ray Compton backscattering in the photosphere (photospheric albedo) has been used to deduce the primary X-ray flare spectra. The mean electron flux distribution has been analysed using both forward fitting and model-independent inversion methods of spectral analysis. We show that the contribution of the photospheric albedo to the photon spectrum modifies the calculated mean electron flux distribution, mainly at energies below similar to 100 keV. The positions of the H alpha emission and hard X-ray sources with respect to the current-free extrapolation of the MDI photospheric magnetic field and the characteristics of the radio emission provide evidence of the closed geometry of the magnetic field Structure and the flare process in low altitude magnetic loops. In agreement with the predictions of some solar flare models, the hard X-ray sources are located on the external edges of the H alpha emission and show chromospheric plasma heated by the non-thermal electrons. The fast changes of H alpha intensities are located not only inside the hard X-ray sources, as expected if they are the signatures of the chromospheric response to the electron bombardment, but also away from them. C1 Acad Sci Czech Republic, Inst Astron, CS-25165 Ondrejov, Czech Republic. Univ Glasgow, Dept Phys & Astron, Glasgow G12 8QQ, Lanark, Scotland. NASA, Goddard Space Flight Ctr, Sci Syst & Applicat Inc, Greenbelt, MD 20771 USA. RP Kasparova, J (reprint author), Acad Sci Czech Republic, Inst Astron, CS-25165 Ondrejov, Czech Republic. EM kasparov@asu.cas.cz RI Kontar, Eduard/B-7897-2008; Dennis, Brian/C-9511-2012; Kasparova, Jana/G-9024-2014; Karlicky, Marian/G-9023-2014 OI Kontar, Eduard/0000-0002-8078-0902; NR 48 TC 24 Z9 25 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 NOV-DEC PY 2005 VL 232 IS 1-2 BP 63 EP 86 DI 10.1007/s11207-005-1581-9 PG 24 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 006TO UT WOS:000234920400004 ER PT J AU Sylwester, J Sylwester, B Kordylewski, Z Phillips, KJH Kuznetsov, VD Boldyrev, SI AF Sylwester, J Sylwester, B Kordylewski, Z Phillips, KJH Kuznetsov, VD Boldyrev, SI TI Observations of solar x-ray spectra by the DIOGENESS and RESIK spectrometers onboard the CORONAS-F satellite SO SOLAR SYSTEM RESEARCH LA English DT Article; Proceedings Paper CT 1st Satellite Conference on CORONAS-F Project 2005 CY JAN 31-FEB 05, 2005 CL Russian Acad Sci, Pushkov Inst Terrestrial Magnet, Ionosphere, & Radio Wav, Moscow, RUSSIA HO Russian Acad Sci, Pushkov Inst Terrestrial Magnet, Ionosphere, & Radio Wav ID CALCIUM ABUNDANCE; WAVELENGTHS; PLASMAS AB The first scientific results of the analysis of the X-ray spectra of flares and active regions in the solar corona obtained by Polish-led spectrometers RESIK and DIOGENESS onboard the CORONAS-F satellite are presented. The instruments were designed and made in the Solar Physics Division of the Space Research Center of the Polish Academy of Sciences (SRC PAS, Wroclaw, Poland). The Institute of Terrestrial Magnetism, Ionosphere, and Radio Wave Propagation (IZMIRAN, Russia) and the Astronomical Institute of the Czech Academy of Sciences also participated in designing the DIOGENESS spectrometer, while IZMIRAN (Russia), Mullard Space Science Laboratory (MSSL, Great Britain), Rutherford Appleton Laboratory (RAL, Great Britain), and Naval Research Laboratory (NRL, United States) contributed to the development of the RESIK spectrometer. In the paper, we give spectra obtained in a number of previously unstudied spectral ranges and a preliminary identification of new spectral lines. The results for the shifts of the X-ray spectral lines observed with the use of a so-called dopplerometer configuration are also presented. Methods for determining the abundances of the rare elements in the solar corona, including chlorine, potassium, and argon, are described. C1 Polish Acad Sci, Ctr Space Res, PL-51622 Wroclaw, Poland. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Russian Acad Sci, Pushkov Inst Terr Magnetism Ionosphere & Radiowav, Troitsk 142090, Moscow Oblast, Russia. RP Sylwester, J (reprint author), Polish Acad Sci, Ctr Space Res, Kopernika 11, PL-51622 Wroclaw, Poland. NR 15 TC 2 Z9 2 U1 2 U2 2 PU MAIK NAUKA/INTERPERIODICA PI NEW YORK PA C/O KLUWER ACADEMIC-PLENUM PUBLISHERS, 233 SPRING ST, NEW YORK, NY 10013-1578 USA SN 0038-0946 J9 SOLAR SYST RES+ JI Solar Syst. Res. PD NOV-DEC PY 2005 VL 39 IS 6 BP 479 EP 488 DI 10.1007/s11208-005-0061-y PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 996CC UT WOS:000234151000007 ER PT J AU Broks, BHP Brok, WJM Remy, J van der Mullen, JJAM Benidar, A Biennier, L Salama, F AF Broks, BHP Brok, WJM Remy, J van der Mullen, JJAM Benidar, A Biennier, L Salama, F TI Modeling the influence of anode-cathode spacing in a pulsed discharge nozzle SO SPECTROCHIMICA ACTA PART B-ATOMIC SPECTROSCOPY LA English DT Article DE polycyclic aromatic hydrocarbons; diffuse interstellar medium; direct current glow discharge; argon metastables; discharge modeling ID CROSS SECTIONS; IONIZATION; SPECTROSCOPY; ARGON; JET; ELECTRONS; RADICALS; DENSITY; ATOMS; IONS AB The pulsed discharge nozzle (PDN) is a spectrochemical source that is designed to produce and cool molecular ions in an astrophysically relevant environment in the laboratory with limited fragmentation. In order to gain a better understanding of the PDN and to optimize the yield of molecular ions and radicals in the PDN source, a parameter study of the influence of the interelectrode distance on the plasma properties is carried out by means of a discharge model, providing a qualitative as well as a quantitative picture of the plasma. We model the electron density and energy, as well as the argon ion and metastable atom number density for various interelectrode distances. The results reveal that increasing the interelectrode distance does not significantly influence the plasma at the cathode and at the anode. However, a positive column forms between the electrodes, which increases in length as the interelectrode distance increases. This is an additional evidence that the PDN is a glow discharge. This positive column does not contribute significantly to the formation of metastable argon atoms. Because metastable argon is thought to be the primary agent in the formation of molecular ions through Penning ionization of the neutral molecular precursor there is no benefit to be expected from an increase of the interelectrode distance. In fact, electron impact dissociation of the molecules in the column might even make the source less efficient for longer column lengths. The simulations presented here provide physical insight into the characteristics of interstellar species analogs in laboratory experiments. (c) 2005 Elsevier B.V. All rights reserved. C1 Eindhoven Univ Technol, Dept Appl Phys, NL-5600 MB Eindhoven, Netherlands. Univ Rennes 1, Lab Phys Atomes Lasers Mol & Surfaces, UMR 6627, CNRS, F-35042 Rennes, France. NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. RP van der Mullen, JJAM (reprint author), Eindhoven Univ Technol, Dept Appl Phys, POB 513, NL-5600 MB Eindhoven, Netherlands. EM j.j.a.m.v.d.mullen@tue.nl RI Salama, Farid/A-8787-2009; benidar, abdessamad/O-1624-2014; Biennier, Ludovic/O-1618-2014 OI Salama, Farid/0000-0002-6064-4401; NR 35 TC 7 Z9 8 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0584-8547 J9 SPECTROCHIM ACTA B JI Spectroc. Acta Pt. B-Atom. Spectr. PD NOV PY 2005 VL 60 IS 11 BP 1442 EP 1449 DI 10.1016/j.sab.2005.08.012 PG 8 WC Spectroscopy SC Spectroscopy GA 994PS UT WOS:000234044300007 ER PT J AU Miyoshi, K Farmer, SC Sayir, A AF Miyoshi, K Farmer, SC Sayir, A TI Wear properties of two-phase Al2O3/ZrO2 (Y2O3) ceramics at temperatures from 296 to 1073 K SO TRIBOLOGY INTERNATIONAL LA English DT Article DE ceramic; wear resistance; high-temperature; dry wear; sliding friction; microhardness ID ZIRCONIA-TOUGHENED ALUMINA; RESISTANCE; MICROSTRUCTURE; COMPOSITES; BEHAVIOR AB Reciprocating sliding friction experiments were conducted with various two-phase, directionally solidified Al2O3/ZrO2 (Y2O3) pins sliding on B4C flats in air at temperatures of 296, 873, and 1073 K under dry sliding conditions. Results indicate that all the Al2O3/ZrO2 (Y2O3) ceramics, from highly Al2O3-rich to ZrO2-rich, exceed the main wear criterion requirement of 10(-6) mm(3) N-1 m(-1) or lower for effective wear-resistant applications. Particularly, the eutectics and Al2O3-rich ceramics showed superior wear properties. The composition and microstructure of Al2O3/ZrO2 (Y2O3) ceramics played a dominant role in controlling the wear and friction properties. The controlling mechanism of the ceramic wear, friction, and hardness was an intrinsic effect involving the resistance to shear fracture of heterophase bonding and cohesive bonding and the interlocking microstructures at different scales in the ceramics. (c) 2005 Elsevier Ltd. All rights reserved. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. Case Western Reserve Univ, Cleveland, OH 44106 USA. RP Miyoshi, K (reprint author), NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. EM kazuhisa.miyoshi-1@nasa.gov; kazuhisamiyoshi-1@nasa.gov; kazuhisa.miyoshi-1@nasa.gov NR 18 TC 14 Z9 15 U1 1 U2 11 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0301-679X J9 TRIBOL INT JI Tribol. Int. PD NOV-DEC PY 2005 VL 38 IS 11-12 BP 974 EP 986 DI 10.1016/j.triboint.2005.07.025 PG 13 WC Engineering, Mechanical SC Engineering GA 993VO UT WOS:000233983700009 ER PT J AU Heshmat, H Hryniewicz, P Walton, JF Willis, JP Jahanmir, S DellaCorte, C AF Heshmat, H Hryniewicz, P Walton, JF Willis, JP Jahanmir, S DellaCorte, C TI Low-friction wear-resistant coatings for high-temperature foil bearings SO TRIBOLOGY INTERNATIONAL LA English DT Article ID TRIBOLOGICAL CHARACTERIZATION; COMPOSITE COATINGS; JOURNAL BEARINGS; HIGH-SPEED; PERFORMANCE; DEPOSITION AB Compliant foil bearings offer many advantages over rolling element bearings in high-speed and high-temperature applications. However, implementation of foil bearings in these applications requires development of solid lubricant coatings that can survive the severe operating conditions encountered at high speeds and high temperatures. The objective of this paper is to present results on development of an advanced coating system for use with compliant foil bearings that permits higher operating speeds and temperatures. In order to evaluate the coating performance and to select the best coating combination for implementation, tests were conducted using a high-temperature, high-speed tribometer. In these tests, Inconel test substrates, representative of a portion of a foil bearing, were coated with several different Korolon (TM) coatings. The counterface disks were coated with a dense chrome, plasma sprayed PS304, hard chrome and Korolon (TM) 1350B. Each test was conducted for 500 start-stop cycles up to 810 degrees C foil pad temperature under 13.8 kPa normal loading. The test results confirmed the excellent tribological behavior of Korolon (TM) coatings for high-speed, high-temperature foil bearing applications. While the tribological behavior of Korolon (TM) coatings were determined to be a function of temperature, in most cases a minimum coefficient of friction less than 0.1 was observed during startup/shutdown periods. Based on the measured coefficient of friction and post-test visual inspection of the mating surfaces, the hard chrome coating proved unacceptable for high-temperature applications due to extensive surface cracking. The other disk coatings exhibited excellent tribological performance. Following these tests, a foil journal bearing was designed and a composite coating consisting of Korolon (TM) 1350A with an overcoat of Korolon (TM) 1 800 was applied to the bearing top foil; and a dense chrome coating was applied to the journal surface. The foil bearing and journal were installed in a 240-lb thrust turbojet engine and operated successfully to 54,000 rpm for over 70 start-stop cycles and 14 It. (c) 2005 Elsevier Ltd. All rights reserved. C1 Mohawk Innovat Technol Inc, Albany, NY 12205 USA. NASA, John Glen Res Ctr, Cleveland, OH 44135 USA. RP Heshmat, H (reprint author), Mohawk Innovat Technol Inc, 1037 Watervliet Shaker Rd, Albany, NY 12205 USA. NR 39 TC 38 Z9 42 U1 4 U2 24 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0301-679X J9 TRIBOL INT JI Tribol. Int. PD NOV-DEC PY 2005 VL 38 IS 11-12 BP 1059 EP 1075 DI 10.1016/j.triboint.2005.07.036 PG 17 WC Engineering, Mechanical SC Engineering GA 993VO UT WOS:000233983700017 ER PT J AU Bindschadler, R Choi, H Shuman, C Markus, T AF Bindschadler, R Choi, H Shuman, C Markus, T TI Detecting and measuring new snow accumulation on ice sheets by satellite remote sensing SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE snowfall; ice sheets; microwave emission; SSMI; ICESat; snow event ID PASSIVE MICROWAVE DATA; SURFACE MASS-BALANCE; DRONNING MAUD LAND; SPATIAL VARIABILITY; ANTARCTICA; ATMOSPHERE; ALGORITHM; MODEL; OCEAN AB A new technique is described that detects when and where new snow falls on ice sheets and then determines the thickness of new accumulation. Measurements of vertically polarized passive emission at 85 GHz are filtered with the Hilbert-Huang Transform to identify periods where the surface snow has changed significantly. These are shown to be commonly the result of new snow by comparison with both field observations and in situ instrumentation. Temperature, atmospheric emission and clouds all affect the passive microwave signal but each is examined and shown not to prevent the identification of new snow events. The magnitude of the brightness temperature change is not strongly correlated with snowfall amount. To quantify the amount of new snow, the spatial extent and timing of new snowfalls are examined with ICESat/ GLAS laser altimetry data. Crossover differences between altimetric profiles taken before, during, and after the snowfall event provide a measure of the thickness of new snow. Specific cases are presented where 11 and 13 cm of new snow were detected over large regions. (C) 2005 Elsevier Inc. All rights reserved. C1 SAIC, Beltsville, MD 20705 USA. NASA, Cryospher Sci Branch, Hydrospher & Biospher Sci Lab, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NASA, Instrumentat Sci Branch, Hydrospher & Biospher Sci Lab, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Choi, H (reprint author), SAIC, Beltsville, MD 20705 USA. EM Robert.A.Bindschadler@nasa.gov; choi@ice.gsfc.nasa.gov RI Markus, Thorsten/D-5365-2012 NR 29 TC 19 Z9 21 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 OCT 30 PY 2005 VL 98 IS 4 BP 388 EP 402 DI 10.1016/j.rse.2005.07.014 PG 15 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 984ET UT WOS:000233286000002 ER PT J AU Nezlin, NP DiGiacomo, PM Stein, ED Ackerman, D AF Nezlin, NP DiGiacomo, PM Stein, ED Ackerman, D TI Stormwater runoff plumes observed by SeaWiFS radiometer in the Southern California Bight SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE ocean color; sea-spectral reflectance; freshwater discharge; plumes; precipitation; Southern California Bight; 32 degrees 00 '-34 degrees 30 ' N; 120 degrees 00 '-117 degrees 00 ' W ID SANTA-BARBARA CHANNEL; OCEAN COLOR DATA; COASTAL WATERS; SEDIMENT PLUMES; MONICA BAY; 1ST FLUSH; QUALITY; BASIN; DISCHARGES; IMPACTS AB Understanding the factors that influence the incidence and dispersal patterns of freshwater runoff plumes in southern California is important for management of coastal water quality. Significant river discharge is associated with episodic winter rainstorms, leading to turbid pollutant and pathogen-laden stormwater plumes that are clearly visible nearshore in the Southern California Bight. We analyzed 1.1-km spatial resolution sea-spectral reflectance data acquired in 1997-2003 by the Sea-viewing Wide Field-of-view Sensor (SeaWiFS), focusing on four regions with distinctive adjacent watershed properties: Ventura, Santa Monica Bay, San Pedro Shelf, and Orange County/San Diego. The area of each plume was detected by the backscattering characteristics of surface waters, i.e., normalized water-leaving radiation of green-yellow wavelength 555 nm (nLw555). Plume area size was correlated with the rainstorm magnitude, which was estimated from atmospheric precipitation averaged over the total area of the watersheds connected to the seashore. The time lag between rainstorm and maximum plume was one day in San Pedro Shelf and two days in other three regions. Assessing maximum correlation between precipitated rainwater and the plume size, we estimated the optimal nLw555 values best characterizing the plume boundaries in each of the four study regions. Another quantitative characteristic derived from maximum correlation between rainwater and plume size was the "coefficient of persistence", related to the speed of freshwater discharge and the time of plume water dissipation; it was also different in different watersheds. The primary factors regulating the relationship between rainstorm and plume were watershed land-use characteristics, size, and elevation. (C) 2005 Elsevier Inc. All rights reserved. C1 So Calif Coastal Water Res Project, Westminster, CA 92683 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Nezlin, NP (reprint author), So Calif Coastal Water Res Project, Westminster, CA 92683 USA. EM nikolayn@sccwrp.org RI Stein, Eric/A-9362-2008; DiGiacomo, Paul/F-5584-2010 OI Stein, Eric/0000-0002-4729-809X; DiGiacomo, Paul/0000-0003-4550-1899 NR 50 TC 49 Z9 51 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 OCT 30 PY 2005 VL 98 IS 4 BP 494 EP 510 DI 10.1016/j.rse.2005.08.008 PG 17 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 984ET UT WOS:000233286000010 ER PT J AU Kelley, OA Stout, J Halverson, JB AF Kelley, OA Stout, J Halverson, JB TI Hurricane intensification detected by continuously monitoring tall precipitation in the eyewall SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID AIRBORNE; CONVECTION AB Previous studies show that a single observation of tall precipitation in a hurricane's eyewall is often associated with intensification of that hurricane's surface wind. Using WSR-88D radars, we show that repeated observation of precipitation height provides even more information about wind intensification. If the frequency of tall precipitation in the eyewall is at least 33% (1 in 3 radar volume scans), we find an 82% chance of wind intensification. If this threshold is not met, the chance of wind intensification drops from 82% to just 17%. We show that the WSR-88D height measurements are reasonable using the TRMM Precipitation Radar. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. George Mason Univ, Ctr Earth Observing & Space Res, Fairfax, VA 22030 USA. Univ Maryland Baltimore Cty, Joint Ctr Earth Syst Technol, Baltimore, MD 21228 USA. RP Kelley, OA (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM okelley@gmu.edu NR 15 TC 10 Z9 11 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 OCT 29 PY 2005 VL 32 IS 20 AR L20819 DI 10.1029/2005GL023583 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 981RH UT WOS:000233105200003 ER PT J AU Fishman, J Creilson, JK Wozniak, AE Crutzen, PJ AF Fishman, J Creilson, JK Wozniak, AE Crutzen, PJ TI Interannual variability of stratospheric and tropospheric ozone determined from satellite measurements SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID QUASI-BIENNIAL OSCILLATION; INDIAN-OCEAN EXPERIMENT; AIR-POLLUTION; SEASONAL VARIABILITY; SUMMER MONSOON; RAINFALL; CIRCULATION; QBO; ATMOSPHERE; RESIDUALS AB Long-term satellite records have been used in previous studies to examine both trends and interannual variability (IAV) of ozone in the stratosphere. In this study, we use satellite measurements to produce long-term records of both tropospheric and stratospheric ozone and we examine the IAV of these data sets. Our analysis of the stratospheric component of these observations is consistent with previous findings for total ozone that show a strong correlation with the quasi-biennial oscillation (QBO) at low latitudes. For tropospheric ozone, we find that there are strong regional enhancements due to in situ generation from large emissions. The IAV of some of these regional enhancements, on the other hand, are strongly correlated with the phase of El Nino-Southern Oscillation (ENSO) and are consistent with our understanding of how regions of subsidence are more conducive to the in situ production of ozone pollution. The insight gained from this study will hopefully provide a better understanding between prevailing meteorological conditions and the evolution of widespread ozone episodes on shorter timescales with the eventual goal of producing an air quality forecasting capability so that exposure of the human population to elevated levels of ozone can be reduced. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. Max Planck Inst Chem, D-55020 Mainz, Germany. SAIC, Hampton, VA USA. Univ Calif San Diego, Scripps Inst Oceanog, La Jolla, CA 92093 USA. RP NASA, Langley Res Ctr, Mail Stop 401A, Hampton, VA 23681 USA. EM jack.fishman@nasa.gov; j.k.creilson@larc.nasa.gov; a.e.wozniak@larc.nasa.gov; air@mpch-mainz.mpg.de RI Crutzen, Paul/F-6044-2012 NR 53 TC 26 Z9 27 U1 0 U2 8 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 OCT 28 PY 2005 VL 110 IS D20 AR D20306 DI 10.1029/2005JD005868 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 981RU UT WOS:000233106500003 ER PT J AU Wozniak, AE Fishman, J Wang, PH Creilson, JK AF Wozniak, AE Fishman, J Wang, PH Creilson, JK TI Distribution of stratospheric column ozone (SCO) determined from satellite observations: Validation of solar backscattered ultraviolet (SBUV) measurements in support of the tropospheric ozone residual (TOR) method SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID MERIDIONAL DISTRIBUTION; TOMS MEASUREMENTS; CLIMATOLOGY; AIR; POLLUTION; PROFILES; NETWORK; QUALITY; AFRICA; TRENDS AB The global (50 degrees N-50 degrees S) distribution of stratospheric column ozone (SCO) is derived using solar backscattered ultraviolet (SBUV) profiles and compared with SCO amounts derived from Stratospheric Aerosol and Gas Experiment (SAGE) and ground-based measurements. An evaluation of archived SBUV (version 6) ozone profiles with ozonesonde profiles shows that the low resolution of the SBUV instrument in the troposphere and lower stratosphere leads to a low bias in the SBUV profile in the troposphere and a high bias in the lower stratosphere in regions where anthropogenic tropospheric ozone production influences the climatology. An empirical correction applied to the SBUV profile prior to separating the stratosphere from the troposphere reduces the bias in the lower stratosphere and results in a SCO distribution in good agreement with SCO derived from SAGE ozone profiles. Because the empirical correction is most pronounced at northern middle latitudes, we compare these resultant SCO values with those measured at two northern middle latitude sites (Wallops Island and Hohenpeissenberg) using concurrent measurements from Dobson spectrophotometers and ozonesondes. Our analysis shows that the empirically corrected SCO at these sites captures the seasonal cycle of SCO as well as the seasonal cycle derived from SAGE stratospheric ozone profiles. These results have important implications for the derivation of tropospheric ozone from SBUV ozone profiles in conjunction with Total Ozone Mapping Spectrometer (TOMS) total ozone measurements using the tropospheric ozone residual (TOR) methodology. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. Sci Applicat Int Corp, Hampton, VA USA. Sci & Technol Corp, Hampton, VA 23666 USA. RP NASA, Goddard Space Flight Ctr, Code 613-3, Greenbelt, MD 20771 USA. EM a.e.wozniak@larc.nasa.gov; jack.fishman@nasa.gov; p.wang@larc.nasa.gov; j.k.creilson@larc.nasa.gov NR 41 TC 12 Z9 12 U1 0 U2 0 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 OCT 28 PY 2005 VL 110 IS D20 AR D20305 DI 10.1029/2005JD005842 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 981RU UT WOS:000233106500002 ER PT J AU Durkin, GA Simon, C AF Durkin, GA Simon, C TI Multipartite entanglement inequalities via spin vector geometry SO PHYSICAL REVIEW LETTERS LA English DT Article ID STATES AB We introduce inequalities for multipartite entanglement, derived from the geometry of spin vectors. The criteria are constructed iteratively from cross and dot products between the spins of individual subsystems, each of which may have arbitrary dimension. For qubit ensembles the maximum violation for our inequalities is larger than that for the Mermin-Klyshko Bell inequalities, and the maximally violating states are different from Greenberger-Horne-Zeilinger states. Our inequalities are violated by certain bound entangled states for which no Bell-type violation has yet been found. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Grenoble 1, CNRS, Spectrometrie Phys Lab, St Martin Dheres, France. RP CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,Mail Stop 126-347, Pasadena, CA 91109 USA. RI Simon, Christoph/F-8163-2010 NR 25 TC 11 Z9 11 U1 1 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 28 PY 2005 VL 95 IS 18 AR 180402 DI 10.1103/PhysRevLett.95.180402 PG 4 WC Physics, Multidisciplinary SC Physics GA 978QF UT WOS:000232887400002 PM 16383878 ER PT J AU Carter, SG Birkedal, V Wang, CS Coldren, LA Maslov, AV Citrin, DS Sherwin, MS AF Carter, SG Birkedal, V Wang, CS Coldren, LA Maslov, AV Citrin, DS Sherwin, MS TI Quantum coherence in an optical modulator SO SCIENCE LA English DT Article ID INDUCED TRANSPARENCY; FANO INTERFERENCE; WELLS DRIVEN; ABSORPTION; FIELD; LIGHT; STORAGE AB Semiconductor quantum well electroabsorption modulators are widely used to modulate near-infrared (NIR) radiation at frequencies below 0.1 terahertz (THz). Here, the NIR absorption of undoped quantum welts was modulated by strong electric fields with frequencies between 1.5 and 3.9 THz. The THz field coupled two excited states (excitons) of the quantum wells, as manifested by a new THz frequency- and power-dependent NIR absorption line. Nonperturbative theory and experiment indicate that the THz field generated a coherent quantum superposition of an absorbing and a nonabsorbing exciton. This quantum coherence may yield new applications for quantum well modulators in. optical communications. C1 Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA. Univ Calif Santa Barbara, Inst Quantum & Complex Dynam, Santa Barbara, CA 93106 USA. Univ Calif Santa Barbara, Dept Elect & Comp Engn, Santa Barbara, CA 93106 USA. NASA, Ames Res Ctr, Ctr Nanotechnol, Moffett Field, CA 94035 USA. Georgia Inst Technol, Atlanta, GA 30332 USA. Georgia Tech Lorraine, Metz Technopole, F-57070 Metz, France. RP Sherwin, MS (reprint author), Univ Calif Santa Barbara, Dept Phys, Broida Hall Bldg 572,Room 3410, Santa Barbara, CA 93106 USA. EM sherwin@physics.ucsb.edu RI Maslov, Alexey/E-5158-2011; Carter, Sam/G-4589-2012; Birkedal, Victoria/C-8899-2015 OI Maslov, Alexey/0000-0002-7835-2474; Birkedal, Victoria/0000-0002-1360-8870 NR 21 TC 90 Z9 91 U1 1 U2 23 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 OCT 28 PY 2005 VL 310 IS 5748 BP 651 EP 653 DI 10.1126/science.1116195 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 980ET UT WOS:000232997700034 PM 16254182 ER PT J AU Hoff, RM Palm, SP Engel-Cox, JA Spinhirne, J AF Hoff, RM Palm, SP Engel-Cox, JA Spinhirne, J TI GLAS long-range transport observation of the 2003 California forest fire plumes to the northeastern US SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID POLLUTION; AEROSOLS; MODIS; LAND AB In October 2003, a series of forest and brush fires in southern California burned an area of over 2750 km 2 with plumes reaching up to 6 km in altitude over the Pacific Ocean. On October 27, 2003, the Santa Ana (foehn) conditions flowing westward out of the desert that fueled the combustion ceased and a portion of the smoke plumes turned and headed eastward. The Geoscience Laser Altimeter System (GLAS) on ICESat provided aerosol profiles of the smoke along numerous ICESat tracks acquired throughout the week following the reversal of the smoke plume. The GLAS observations place the height of the smoke aerosols at <7 km as the smoke moved eastward over North America. GLAS measurement cross-sections often preceded or trailed the main smoke pulses by a few hours and capturing the four-dimensional picture of this moving target was only possible by combining multiple sensor observations with back trajectory calculations. C1 Univ Maryland Baltimore Cty, Joint Ctr Earth Syst Technol, Baltimore, MD 21228 USA. NASA, Sci Syst Applicat Int, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Battelle Mem Inst, Arlington, VA 22201 USA. RP Univ Maryland Baltimore Cty, Joint Ctr Earth Syst Technol, 5523 Res Pk Dr,Suite 320, Baltimore, MD 21228 USA. EM hoff@umbc.edu; spp@virl.gsfc.nasa.gov; engelcoxj@battelle.org; jspin@virl.gsfc.nasa.gov RI Hoff, Raymond/C-6747-2012 NR 16 TC 14 Z9 14 U1 1 U2 2 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 OCT 27 PY 2005 VL 32 IS 22 AR L22S08 DI 10.1029/2005GL023723 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 981RK UT WOS:000233105500001 ER PT J AU Pierangelo, C Mishchenko, M Balkanski, Y Chedin, A AF Pierangelo, C Mishchenko, M Balkanski, Y Chedin, A TI Retrieving the effective radius of Saharan dust coarse mode from AIRS SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID AEROSOL-SIZE DISTRIBUTION; OPTICAL-PROPERTIES; ABSORPTION AB We show that the effective radius of the dust coarse mode can be retrieved from Aqua/AIRS observations, using a two step process. First, for each AIRS observation, the dust infrared optical depth, the mean altitude of the dust layer and an estimate of the temperature and water vapor profiles are obtained from 8 spectral channels, using a Look-Up-Table approach. Second, the effective radius is obtained from an additional AIRS channel (located at 9.32 mu m), selected for its sensitivity to dust particle size and its insensitivity to dust particle shape or to other potential contaminants (ozone, for example). The dust coarse mode effective radius is retrieved from AIRS over the Atlantic Ocean for the period April to June 2003. It compares well with in situ measurements, transport model simulations and sun-photometer retrievals. We find that the coarse mode effective radius decreases slightly with transport distance, from 2.4 mu m to about 2 mu m. C1 Ecole Polytech, Meteorol Dynam Lab, Inst Pierre Simon Laplace, F-91128 Palaiseau, France. CEA, Lab Sci Climat & Environm, Inst Pierre Simon Laplace, F-91191 Gif Sur Yvette, France. Columbia Univ, NASA, Goddard Inst Space Studies, New York, NY 10025 USA. RP Ecole Polytech, Meteorol Dynam Lab, Inst Pierre Simon Laplace, F-91128 Palaiseau, France. EM clemence.pierangelo@lmd.polytechnique.fr RI Balkanski, Yves/A-6616-2011; Mishchenko, Michael/D-4426-2012 OI Balkanski, Yves/0000-0001-8241-2858; NR 17 TC 25 Z9 25 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 OCT 27 PY 2005 VL 32 IS 20 AR L20813 DI 10.1029/2005GL023425 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 981RF UT WOS:000233105000001 ER PT J AU Siegel, DA Maritorena, S Nelson, NB Behrenfeld, MJ McClain, CR AF Siegel, DA Maritorena, S Nelson, NB Behrenfeld, MJ McClain, CR TI Colored dissolved organic matter and its influence on the satellite-based characterization of the ocean biosphere SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID GLOBAL OCEAN; PHYTOPLANKTON BLOOMS; CHLOROPHYLL-A; ALGORITHM; WATERS; MODELS AB Satellite ocean color data enable the global assessment of the ocean biosphere through determinations of chlorophyll concentrations. However, ocean color is not a function of chlorophyll alone. We assess differences between two ocean color models with nearly identical validation statistics. The resulting chlorophyll retrievals show systematic differences which are consistent with each model's ability to account for the absorption of light by colored dissolved organic materials. These differences are often large and approach 100% poleward of 40 degrees latitude. We conclude that the discrepancies are due to fundamental differences in model assumptions and their empirical tuning using geographically limited, in situ data. This source of uncertainty is important as the choice of ocean color model alters modeled rates of global net primary production by more than 30%. The ultimate resolution of this issue requires continued improvements in remote sensing algorithms and validation data as well as satellite technology. C1 Univ Calif Santa Barbara, Inst Computat Earth Syst Sci, Santa Barbara, CA 93106 USA. Oregon State Univ, Dept Bot & Plant Pathol, Corvallis, OR 97331 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Siegel, DA (reprint author), Univ Calif Santa Barbara, Inst Computat Earth Syst Sci, 6844 Ellison Hall, Santa Barbara, CA 93106 USA. EM davey@icess.ucsb.edu RI Siegel, David/C-5587-2008; Nelson, Norman/B-7343-2014 OI Nelson, Norman/0000-0003-1767-7598 NR 29 TC 68 Z9 69 U1 2 U2 13 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 OCT 27 PY 2005 VL 32 IS 20 AR L20605 DI 10.1029/2005GL024310 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 981RF UT WOS:000233105000007 ER PT J AU Kahre, MA Murphy, JR Haberle, RM Montmessin, F Schaeffer, J AF Kahre, MA Murphy, JR Haberle, RM Montmessin, F Schaeffer, J TI Simulating the Martian dust cycle with a finite surface dust reservoir SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID THERMAL EMISSION SPECTROMETER; GENERAL-CIRCULATION MODEL; INTERANNUAL VARIABILITY; ATMOSPHERIC DYNAMICS; MAPPER OBSERVATIONS; POLAR-REGIONS; MARS; STORMS; INERTIA AB Multiple year General Circulation Model (GCM) simulations that include a finite surface dust reservoir and an infinite surface dust reservoir are compared. While the infinite dust reservoir simulations produce a highly repeatable annual dust cycle, the finite surface dust reservoir simulations evolve quickly towards a low-dust condition. Once a region is swept clean of available surface dust, it reacquires only small amounts of dust during northern summer but it is repeatedly swept clean during each subsequent dust storm season (southern spring and summer). This argues against a finite dust reservoir as a mechanism for the interannual variability of global dust storms. Additionally, these results suggest that the regions of preferred wind stress lifting are deep dust reservoirs that are not depleted and resupplied on annual or decadal timescales. Therefore, the dust cycle must be closed on much longer timescales, possibly those associated with orbital variations. C1 New Mexico State Univ, Dept Astron, Las Cruces, NM 88003 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Kahre, MA (reprint author), New Mexico State Univ, Dept Astron, MSC 4500,Box 30001, Las Cruces, NM 88003 USA. EM kahrema@nmsu.edu NR 20 TC 18 Z9 18 U1 0 U2 3 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 OCT 26 PY 2005 VL 32 IS 20 AR L20204 DI 10.1029/2005GL023495 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 981RE UT WOS:000233104900003 ER PT J AU Martin, CF Thomas, RH Krabill, WB Manizade, SS AF Martin, CF Thomas, RH Krabill, WB Manizade, SS TI ICESat range and mounting bias estimation over precisely-surveyed terrain SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article AB Prior to the launch of the Geoscience Laser Altimeter System (GLAS) on the Ice, Cloud and land Elevation Satellite (ICESat) in January 2003, topographic surveys were made by NASA's Airborne Topographic Mapper (ATM) over regions of the western United States and the Antarctic Dry Valleys to support calibration and validation of the range and pointing errors of GLAS lasers. Surveyed areas included terrain with large slopes, allowing pointing-bias estimation with as little as a few seconds of ICESat data. Range errors over sloping irregular surfaces are calculated by computing the expected GLAS return waveform and comparing it with the actual waveform. We conclude that the range bias is less than 2 cm and that pointing errors for the best available data set (Laser 2a) have rss errors less than 2 arcsec. C1 Ctr Estudios Cient, Valdivia, Chile. NASA, EG&G Tech Serv, Wallops Flight Facil, Wallops Isl, VA USA. NASA, Hydrospher & Biospher Sci Lab, Cryospher Sci Branch, Goddard Space Flight Ctr, Wallops Isl, VA 23337 USA. RP Martin, CF (reprint author), Ctr Estudios Cient, Ave Arturo Prat 514,Casilla 1469, Valdivia, Chile. EM chreston_2@comcast.net NR 5 TC 23 Z9 23 U1 2 U2 10 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 OCT 25 PY 2005 VL 32 IS 21 AR L21S07 DI 10.1029/2005GL023800 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 981RI UT WOS:000233105300001 ER PT J AU Rundle, JB Rundle, PB Donnellan, A Turcotte, DL Shcherbakov, R Li, P Malamud, BD Grant, LB Fox, GC McLeod, D Yakovlev, G Parker, J Klein, W Tiampo, KF AF Rundle, JB Rundle, PB Donnellan, A Turcotte, DL Shcherbakov, R Li, P Malamud, BD Grant, LB Fox, GC McLeod, D Yakovlev, G Parker, J Klein, W Tiampo, KF TI A simulation-based approach to forecasting the next great San Francisco earthquake SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article DE hazards; Weilbull distribution ID SOUTHERN-CALIFORNIA; ANDREAS FAULT; PHYSICAL MODEL; RECURRENCE; STRAIN AB In 1906 the great San Francisco earthquake and fire destroyed much of the city. As we approach the 100-year anniversary of that event, a critical concern is the hazard posed by another such earthquake. In this article, we examine the assumptions presently used to compute the probability of occurrence of these earthquakes. We also present the results of a numerical simulation of interacting faults on the San Andreas system. Called Virtual California, this simulation can be used to compute the times, locations, and magnitudes of simulated earthquakes on the San Andreas fault in the vicinity of San Francisco. Of particular importance are results for the statistical distribution of recurrence times between great earthquakes, results that are difficult or impossible to obtain from a purely field-based approach. C1 Univ Calif Davis, Ctr Computat Sci & Engn, Davis, CA 95616 USA. Univ Calif Davis, Dept Geol, Davis, CA 95616 USA. CALTECH, Earth Space Sci Div, Pasadena, CA 91125 USA. CALTECH, Jet Prop Lab, Explorat Syst Auton Sect, Pasadena, CA 91125 USA. Kings Coll London, Dept Geog, London WC2R 2LS, England. Univ Calif Irvine, Dept Environm Hlth Sci & Policy, Irvine, CA 92697 USA. Indiana Univ, Dept Comp Sci, Bloomington, IN 47405 USA. Indiana Univ, Dept Phys, Bloomington, IN 47405 USA. Univ So Calif, Dept Comp Sci, Los Angeles, CA 90089 USA. Boston Univ, Dept Phys, Boston, MA 02215 USA. Univ Western Ontario, Dept Earth Sci, London, ON N6A 5B7, Canada. Univ Western Ontario, Dept Biol & Geol Sci, London, ON N6A 5B7, Canada. RP Rundle, JB (reprint author), Univ Calif Davis, Ctr Computat Sci & Engn, Davis, CA 95616 USA. EM rundle@cse.ucdavis.edu; turcotte@geology.ucdavis.edu RI Ludwig, Lisa Grant/G-6442-2012; Shcherbakov, Robert/I-1036-2012; Malamud, Bruce/H-7885-2013; Tiampo, Kristy/I-1355-2015 OI Ludwig, Lisa Grant/0000-0001-6538-8067; Shcherbakov, Robert/0000-0002-3057-0851; Malamud, Bruce/0000-0001-8164-4825; Tiampo, Kristy/0000-0002-5500-7600 NR 31 TC 20 Z9 21 U1 0 U2 6 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD OCT 25 PY 2005 VL 102 IS 43 BP 15363 EP 15367 DI 10.1073/pnas.05075028102 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 979GC UT WOS:000232929400019 PM 16219696 ER PT J AU Chen, N Gascoin, F Snyder, GJ Muller, E Karpinski, G Stiewe, C AF Chen, N Gascoin, F Snyder, GJ Muller, E Karpinski, G Stiewe, C TI Macroscopic thermoelectric inhomogeneities in (AgSbTe2)(x)(PbTe)(1-x) SO APPLIED PHYSICS LETTERS LA English DT Article ID HALBLEITENDEN MISCHKRISTALLEN; NEUERE UNTERSUCHUNGEN; SYSTEMS AB Exceptionally high thermoelectric figure of merit (zT>2), has been reported for (Ag1-ySbTe2)(0.05)(PbTe)(0.95), which may involve the nanoscale microstructure. However, conflicting reports on the same materials claim only zT of 1 or less. Here we show that (Ag1-ySbTe2)(0.05)(PbTe)(0.95) materials are multiphase on the scale of millimeters despite appearing homogeneous by x-ray diffraction and routine electron microscopy. Using a scanning Seebeck microprobe, we find significant variation of Seebeck coefficient (including both n-type and p-type behavior in the same sample) that can explain the discrepancy in reported zT. More homogeneous samples can be prepared with faster cooling rates. (C) 2005 American Institute of Physics. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. German Aerosp Ctr, Inst Mat Res, D-51170 Cologne, Germany. RP Snyder, GJ (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM jsnyder@jpl.nasa.gov RI Snyder, G. Jeffrey/E-4453-2011; Snyder, G/I-2263-2015; OI Snyder, G. Jeffrey/0000-0003-1414-8682; Chen, Nancy/0000-0001-8966-3449 NR 18 TC 70 Z9 72 U1 3 U2 36 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 OCT 24 PY 2005 VL 87 IS 17 AR 171903 DI 10.1063/1.2056590 PG 3 WC Physics, Applied SC Physics GA 976HK UT WOS:000232723700011 ER PT J AU Cano, CI Weiser, ES Kyu, T Pipes, RB AF Cano, CI Weiser, ES Kyu, T Pipes, RB TI Polyimide foams from powder: Experimental analysis of competitive diffusion phenomena SO POLYMER LA English DT Article DE polyimide; foam; powder ID INDUCED BUBBLE-GROWTH; VISCOUS-LIQUIDS; PRECURSOR; POLYMER; GAS AB In the present study, various diffusive processes have been investigated during foaming of powdered precursors of polyimide. A detailed analysis of the powdered precursor's characteristics allows for an enhanced morphological understanding of the resulting microstructures and foam unit cell. Parameters that are central to the foaming process such as particle morphology, volatile concentration and sorption-desorption processes are evaluated. Isothermal and non-isothermal desorption experiments have been carried out by thermogravimetric analysis (TGA), and specific diffusive processes have been correlated to thermodynamic and kinetic transitions by means of modulated differential scanning calorimetry (MDSC) of the corresponding materials. It was found that two primary fluxes of volatiles, one out of the external surface of the particles (responsible for volatile desorption) and the other into the growing bubble (responsible for vapor supersaturation inside the bubble) compete against each other creating a competitive scenario that becomes the controlling factor for potential inflation within the precursor particles. (c) 2005 Elsevier Ltd. All rights reserved. C1 Univ Akron, Dept Polymer Engn, Akron, OH 44325 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. Purdue Univ, Sch Mat Engn Aeronaut & Astronaut & Chem Engn, W Lafayette, IN 47907 USA. RP Cano, CI (reprint author), Univ Akron, Dept Polymer Engn, Akron, OH 44325 USA. EM cc20@uakron.edu NR 22 TC 17 Z9 17 U1 2 U2 14 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0032-3861 J9 POLYMER JI Polymer PD OCT 24 PY 2005 VL 46 IS 22 BP 9296 EP 9303 DI 10.1016/j.polymer.2005.07.056 PG 8 WC Polymer Science SC Polymer Science GA 975DX UT WOS:000232642300009 ER PT J AU Mayr, HG Mengel, JG Wolff, CL AF Mayr, HG Mengel, JG Wolff, CL TI Wave-driven equatorial annual oscillation induced and modulated by the solar cycle SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID QUASI-BIENNIAL OSCILLATION; DOPPLER-SPREAD PARAMETERIZATION; MIDDLE ATMOSPHERE; SEMIANNUAL OSCILLATION; MOMENTUM DEPOSITION; ARCTIC OSCILLATION; KELVIN WAVE; STRATOSPHERE; VARIABILITY; CIRCULATION AB Our 3-D model for the solar cycle (SC) effect on the QBO ( H. G. Mayr et al., The QBO as potential amplifier of solar cycle influence, submitted to Geophysical Research Letters, 2005, hereinafter referred to as Mayr et al., submitted manuscript, 2005) produces a hemispherically symmetric 12-month Annual Oscillation (AO) in the zonal winds, which is largely confined to low latitudes. This Equatorial Annual Oscillation (EAO) is generated through nonlinear interaction between the dominant anti-symmetric AO and the anti-symmetric component of the SC response. Due to wave-mean-flow interaction from small-scale gravity waves (GW), the SC-modulated EAO is amplified and propagates down through the stratosphere as does the QBO. The amplitude of the EAO is relatively small, but its SC modulation is large and is in phase with that of the QBO. Although the EAO is concentrated at low latitudes, prominent signatures appear in the polar regions where the SC produces measurable temperature variations. At lower altitudes, the GW-driven downward propagation of the EAO affects the phase of the annual cycle and causes the SC effect to be different in the two hemispheres. C1 NASA, Goddard Space Flight Ctr, Atmospher Chem & Dynam Branch, Greenbelt, MD 20771 USA. Sci Syst & Applicat Inc, Lanham, MD 20706 USA. RP Mayr, HG (reprint author), NASA, Goddard Space Flight Ctr, Atmospher Chem & Dynam Branch, Mail Code 910 4, Greenbelt, MD 20771 USA. EM mayr@chapman.gsfc.nasa.gov NR 21 TC 8 Z9 8 U1 2 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 OCT 22 PY 2005 VL 32 IS 20 AR L20811 DI 10.1029/2005GL023090 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 977UL UT WOS:000232828600001 ER PT J AU Mortier, AMJ Serjeant, S Dunlop, JS Scott, SE Ade, P Alexander, D Almaini, O Aretxaga, I Baugh, C Benson, AJ Best, PN Blain, A Bock, J Borys, C Bressan, A Carilli, C Chapin, EL Chapman, S Clements, DL Coppin, K Crawford, M Devlin, M Dicker, S Dunne, L Eales, SA Edge, AC Farrah, D Fox, M Frenk, C Gaztanaga, E Gear, WK Gonzales-Solares, E Granato, GL Greve, TR Grimes, JA Gundersen, J Halpern, M Hargrave, P Hughes, DH Ivison, RJ Jarvis, MJ Jenness, T Jimenez, R van Kampen, E King, A Lacey, C Lawrence, A Lepage, K Mann, RG Marsden, G Mauskopf, P Netterfield, B Oliver, S Olmi, L Page, MJ Peacock, JA Pearson, CP Percival, WJ Pope, A Priddey, RS Rawlings, S Roche, N Robinson, MR Scott, D Sekiguchi, K Seigar, M Silva, L Simpson, C Smail, I Stevens, JA Takagi, T Tucker, G Vlahakis, C Waddington, I Wagg, J Watson, M Willott, C Vaccari, M AF Mortier, AMJ Serjeant, S Dunlop, JS Scott, SE Ade, P Alexander, D Almaini, O Aretxaga, I Baugh, C Benson, AJ Best, PN Blain, A Bock, J Borys, C Bressan, A Carilli, C Chapin, EL Chapman, S Clements, DL Coppin, K Crawford, M Devlin, M Dicker, S Dunne, L Eales, SA Edge, AC Farrah, D Fox, M Frenk, C Gaztanaga, E Gear, WK Gonzales-Solares, E Granato, GL Greve, TR Grimes, JA Gundersen, J Halpern, M Hargrave, P Hughes, DH Ivison, RJ Jarvis, MJ Jenness, T Jimenez, R van Kampen, E King, A Lacey, C Lawrence, A Lepage, K Mann, RG Marsden, G Mauskopf, P Netterfield, B Oliver, S Olmi, L Page, MJ Peacock, JA Pearson, CP Percival, WJ Pope, A Priddey, RS Rawlings, S Roche, N Robinson, MR Scott, D Sekiguchi, K Seigar, M Silva, L Simpson, C Smail, I Stevens, JA Takagi, T Tucker, G Vlahakis, C Waddington, I Wagg, J Watson, M Willott, C Vaccari, M TI The SCUBA half-degree extragalactic survey - I. Survey motivation, design and data processing SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Review DE galaxies : evolution; galaxies : formation; galaxies : starburst; cosmology : observations; infrared : galaxies; submillimetre ID DEEP SUBMILLIMETER SURVEY; STAR-FORMATION HISTORY; CLERK-MAXWELL-TELESCOPE; SPITZER-SPACE-TELESCOPE; SPECTRAL ENERGY-DISTRIBUTIONS; HIERARCHICAL GALAXY FORMATION; REDSHIFT DUSTY GALAXIES; INFRARED ARRAY CAMERA; FLUX-DENSITY RATIO; 14 HOUR FIELD AB The Submillimetre Common-User Bolometer Array ( SCUBA) Half-Degree Extragalactic Survey ( SHADES) is a major new blank-field extragalactic submillimetre (submm) survey currently underway at the James Clerk Maxwell Telescope (JCMT). Ultimately, SHADES aims to cover half a square degree at 450 and 850 mu m to a 4 sigma depth of similar or equal to 8 mJy at 850 mu m. Two fields are being observed, the Subaru/XMM-Newton Deep Field (SXDF) (02(h)18(m) - 05 degrees.) and the Lockman Hole East (10(h)52(m) + 57 degrees). The survey has three main aims: (i) to investigate the population of high-redshift submm galaxies and the cosmic history of massive dust-enshrouded star formation activity; (ii) to investigate the clustering properties of submm-selected galaxies in order to determine whether these objects could be progenitors of present-day massive ellipticals; and (iii) to investigate the fraction of submm-selected sources that harbour active galactic nuclei. To achieve these aims requires that the submm data be combined with cospatial information spanning the radio-to-X-ray frequency range. Accordingly, SHADES has been designed to benefit from ultra-deep radio imaging obtained with the Very Large Array (VLA), deep mid-infrared observations from the Spitzer Space Telescope, submm mapping by the Balloon-borne Large Aperture Submillimetre Telescope ( BLAST), deep near-infrared imaging with the United Kingdom Infrared Telescope, deep optical imaging with the Subaru Telescope and deep X-ray observations with the XMM-Newton observatory. It is expected that the resulting extensive multiwavelength data set will provide complete photometric redshift information accurate to delta(z) <= 0.5 as well as detailed spectral energy distributions for the vast majority of the submm-selected sources. In this paper, the first of a series on SHADES, we present an overview of the motivation for the survey, describe the SHADES survey strategy, provide a detailed description of the primary data-analysis pipeline and demonstrate the superiority of our adopted matched-filter source-extraction technique over, for example, Emerson-II style methods. We also report on the progress of the survey. As of 2004 February, 720 arcmin(2) had been mapped with SCUBA ( about 40 per cent of the anticipated final total area) to a median 1 sigma depth of 2.2 mJy per beam at 850 mu m (25 mJy per beam at 450 mu m), and the source-extraction routines give a source density of 650 +/- 50 sources de(g-)2 > 3 sigma at 850 mu m. Although uncorrected for Eddington bias, this source density is more than sufficient for providing enough sources to answer the science goals of SHADES, once half a square degree is observed. A refined reanalysis of the original 8-mJy survey Lockman hole data was carried out in order to evaluate the new data-reduction pipeline. Of the 17 most secure sources in the original sample, 12 have been reconfirmed, including 10 of the 11 for which radio identifications were previously secured. C1 Univ Kent, Sch Phys Sci, Ctr Astrophys & Planetary Sci, Canterbury CT2 7NR, Kent, England. Univ Edinburgh, Royal Observ, Astron Inst, Edinburgh EH9 3HJ, Midlothian, Scotland. Cardiff Univ, Cardiff Sch Phys & Astron, Cardiff CF24 3YB, Wales. Univ Nottingham, Sch Phys & Astron, Nottingham NG7 2RD, England. INAOE, Puebla 72000, Mexico. Univ Durham, Inst Computat Cosmol, Durham DH1 3LE, England. Univ Oxford, Dept Astrophys, Oxford OX1 3RH, England. CALTECH, Pasadena, CA 91125 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Osserv Astron Padova, I-35122 Padua, Italy. Natl Radio Astron Observ, Socorro, NM 87801 USA. Univ London Imperial Coll Sci & Technol, Blackett Lab, Astrophys Grp, London SW7 2BW, England. Univ British Columbia, Dept Phys & Astron, Vancouver, BC V6T 1Z1, Canada. Univ Penn, Dept Phys & Astron, Philadelphia, PA 19104 USA. CALTECH, Jet Prop Lab, Infrared Proc Anal Ctr, Pasadena, CA 91125 USA. CSIC, IEEC, ES-08034 Barcelona, Spain. Univ Cambridge, Inst Astron, Cambridge CB3 0HA, England. Univ Miami, Dept Phys, Expt Cosmol Lab, Coral Gables, FL 33146 USA. Royal Observ, UK ATC, Edinburgh EH9 3HJ, Midlothian, Scotland. Joint Astron Ctr, Hilo, HI 96720 USA. Univ Innsbruck, Inst Astrophys, A-6020 Innsbruck, Austria. Univ Toronto, Dept Astron & Astrophys, Toronto, ON M5S 3H8, Canada. Univ Sussex, Ctr Astron, Brighton BN1 9QH, E Sussex, England. Osserv Astrofis Arcetri, I-50125 Florence, Italy. UCL, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England. ISAS, Sagamihara, Kanagawa 2298510, Japan. Univ Hertfordshire, Dept Phys Astron & Math, Hatfield AL10 9AB, Herts, England. Natl Astron Observ Japan, Subaru Telescope, Hilo, HI 96720 USA. Univ Calif Irvine, Dept Phys & Astron, Irvine, CA 92697 USA. Osserv Astron Trieste, I-34131 Trieste, Italy. Univ Durham, Dept Phys, Durham DH1 3LE, England. Brown Univ, Dept Phys, Providence, RI 02912 USA. Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. Natl Res Council Canada, Herzberg Inst Astrophys, Victoria, BC V9E 2E7, Canada. RP Mortier, AMJ (reprint author), Univ Kent, Sch Phys Sci, Ctr Astrophys & Planetary Sci, Canterbury CT2 7NR, Kent, England. EM amjb2@star.kent.ac.uk RI Baugh, Carlton/A-8482-2012; Oliver, Seb/A-2479-2013; Smail, Ian/M-5161-2013; Ivison, R./G-4450-2011; Vaccari, Mattia/R-3431-2016; Gaztanaga, Enrique/L-4894-2014; OI Jenness, Tim/0000-0001-5982-167X; Jimenez, Raul/0000-0002-3370-3103; Alexander, David/0000-0002-5896-6313; Scott, Douglas/0000-0002-6878-9840; Baugh, Carlton/0000-0002-9935-9755; Oliver, Seb/0000-0001-7862-1032; Smail, Ian/0000-0003-3037-257X; Ivison, R./0000-0001-5118-1313; Vaccari, Mattia/0000-0002-6748-0577; Gaztanaga, Enrique/0000-0001-9632-0815; Roche, Nathan/0000-0003-1936-3058; Granato, Gian Luigi/0000-0002-4480-6909; Olmi, Luca/0000-0002-1162-7947; Edge, Alastair/0000-0002-3398-6916 NR 126 TC 77 Z9 77 U1 0 U2 2 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD OCT 21 PY 2005 VL 363 IS 2 BP 563 EP 580 DI 10.1111/j.1365-2966.2005.09460.x PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 972GB UT WOS:000232441200011 ER PT J AU Uttley, P McHardy, IM AF Uttley, P McHardy, IM TI X-ray variability of NGC 3227 and 5506 and the nature of active galactic nucleus 'states' SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE methods : statistical; galaxies : active; galaxies : individual : NGC3227; galaxies : individual : NGC 5506; galaxies : Seyfert; X-rays : galaxies ID NARROW-LINE SEYFERT-1; BLACK-HOLE MASSES; CYGNUS X-1; XMM-NEWTON; SPECTRAL VARIABILITY; POWER SPECTRUM; REGION SIZES; SOFT STATE; GALAXIES; LONG AB We use X-ray monitoring data obtained over a broad range of time-scales to measure the broad-band power spectral density functions (PSDs) of two Seyfert galaxies: the broadline-Seyfert 1 NGC 3227 and the Seyfert 2 NGC 5506, which has recently been identified as an obscured narrow-line Seyfert 1 (NLS 1). Using a Monte Carlo fitting technique, we demonstrate that both PSDs are reminiscent of the PSD of black hole X-ray binaries (BHXRBs) in the high/soft state, and specifically rule out a low/hard-state PSD shape in NGC 3227. This result demonstrates that, at least where variability is concerned, broad-line Seyferts with hard X-ray spectra (photon index Gamma similar to 1.6) are not simply the analogues of the low/hard state in BHXRBs, and the dichotomy of NLS 1 and broad-line Seyferts cannot be simply interpreted in terms of the two states. We show that the PSD normalization in NGC 3227 is strongly energy-dependent, with larger variability amplitudes at lower energies, unlike NGC 5506 which shows little energy dependence of variability. We demonstrate that this difference is caused by spectral pivoting of the continuum in NGC 3227 at high energies, which is probably also related to the large amplitude of variability seen in the 2-10 keV band in this active galactic nucleus (AGN). Using the new PSD data and new results in the literature, we replot the PSD break time-scale versus mass plot for all AGNs with PSD breaks measured so far, and demonstrate that higher accretion rate AGNs appear to have relatively shorter break time-scales for their black hole mass than lower accretion rate AGNs. C1 NASA, Goddard Space Flight Ctr, Xray Astrophys Lab, Greenbelt, MD 20771 USA. Univ Southampton, Sch Phys & Astron, Southampton SO17 1BJ, Hants, England. RP Uttley, P (reprint author), NASA, Goddard Space Flight Ctr, Xray Astrophys Lab, Code 662, Greenbelt, MD 20771 USA. NR 61 TC 74 Z9 74 U1 0 U2 0 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD OCT 21 PY 2005 VL 363 IS 2 BP 586 EP 596 DI 10.1111/j.1365-2966.2005.09475.x PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 972GB UT WOS:000232441200018 ER PT J AU Kapale, KT Dowling, JP AF Kapale, KT Dowling, JP TI Vortex phase qubit: Generating arbitrary, counterrotating, coherent superpositions in bose-einstein condensates via optical angular momentum beams SO PHYSICAL REVIEW LETTERS LA English DT Article ID QUANTUM SUPERPOSITION; STATES; HOLOGRAMS; MODES; LIGHT; GAS AB We propose a scheme for the generation of arbitrary coherent superpositions of vortex states in Bose-Einstein condensates (BEC) using the orbital-angular-momentum states of light. We devise a scheme to generate coherent superpositions of two such counterrotating states of light using well-known experimental techniques. We show that a specially designed Raman scheme allows for transfer of the optical vortex-superposition state onto an initially nonrotating BEC. This creates an arbitrary and coherent superposition of a vortex and antivortex pair in the BEC. The ideas presented here could be extended to generate entangled vortex states, design memories for the orbital-angular-momentum states of light, and perform other quantum information tasks. Applications to inertial sensing are also discussed. C1 CALTECH, Jet Prop Lab, Quantum Comp Technol Grp, Pasadena, CA 91109 USA. Louisiana State Univ, Hearne Inst Theoret Phys, Dept Phys & Astron, Baton Rouge, LA 70803 USA. Texas A&M Univ, Inst Quantum Studies, Dept Phys, College Stn, TX 77843 USA. RP Kapale, KT (reprint author), CALTECH, Jet Prop Lab, Quantum Comp Technol Grp, 4800 Oak Grove Dr,Mail Stop 126-347, Pasadena, CA 91109 USA. EM Kishor.T.Kapale@jpl.nasa.gov RI DOWLING, JONATHAN/L-2749-2013 NR 31 TC 85 Z9 85 U1 3 U2 10 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 21 PY 2005 VL 95 IS 17 AR 173601 DI 10.1103/PhysRevLett.95.173601 PG 4 WC Physics, Multidisciplinary SC Physics GA 976HP UT WOS:000232724400031 PM 16383828 ER PT J AU Griffith, CA Penteado, P Baines, K Drossart, P Barnes, J Bellucci, G Bibring, J Brown, R Buratti, B Capaccioni, F Cerroni, P Clark, R Combes, M Coradini, A Cruikshank, D Formisano, V Jaumann, R Langevin, Y Matson, D McCord, T Mennella, V Nelson, R Nicholson, P Sicardy, B Sotin, C Soderblom, LA Kursinski, R AF Griffith, CA Penteado, P Baines, K Drossart, P Barnes, J Bellucci, G Bibring, J Brown, R Buratti, B Capaccioni, F Cerroni, P Clark, R Combes, M Coradini, A Cruikshank, D Formisano, V Jaumann, R Langevin, Y Matson, D McCord, T Mennella, V Nelson, R Nicholson, P Sicardy, B Sotin, C Soderblom, LA Kursinski, R TI The evolution of Titan's mid-latitude clouds SO SCIENCE LA English DT Article ID TROPOSPHERIC CLOUDS; ATMOSPHERE; TEMPERATURES; DYNAMICS; WINDS AB Spectra from Cassini's Visual and Infrared Mapping Spectrometer reveal that the horizontal structure, height, and optical depth of Titan's clouds are highly dynamic. Vigorous cloud centers are seen to rise from the middle to the upper troposphere within 30 minutes and dissipate within the next hour. Their development indicates that Titan's clouds evolve convectively; dissipate through rain; and, over the next several hours, waft downwind to achieve their great longitude extents. These and other characteristics suggest that temperate clouds originate from circulation-induced convergence, in addition to a forcing at the surface associated with Saturn's tides, geology, and/or surface composition. C1 Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Observ Paris, Meudon, France. CNR, Inst Fis Spazio Interplanetario, Rome, Italy. Univ Paris 11, Inst Astrophys Spatiale, Orsay, France. CNR, Inst Astrofis Spaziale & Fis Cosm, Rome, Italy. US Geol Survey, Denver, CO 80225 USA. NASA, Ames Res Ctr, Mountain View, CA USA. Univ Washington, Dept Earth & Space Sci, Seattle, WA 98195 USA. Osserv Astron Capodimonte, I-80131 Naples, Italy. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. Univ Nantes, Lab Planetol & Geodynam, F-44035 Nantes, France. US Geol Survey, Flagstaff, AZ 86001 USA. RP Griffith, CA (reprint author), Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. RI Barnes, Jason/B-1284-2009; Penteado, Paulo/F-9081-2012; OI Barnes, Jason/0000-0002-7755-3530; Penteado, Paulo/0000-0001-6759-2037; Cerroni, Priscilla/0000-0003-0239-2741; Bellucci, Giancarlo/0000-0003-0867-8679; Capaccioni, Fabrizio/0000-0003-1631-4314 NR 30 TC 100 Z9 101 U1 0 U2 14 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 OCT 21 PY 2005 VL 310 IS 5747 BP 474 EP 477 DI 10.1126/science.1117702 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 977EU UT WOS:000232786000041 PM 16239472 ER PT J AU Lehnert, H Stone, R Heimler, W AF Lehnert, H Stone, R Heimler, W TI Two new species of Plakina Schulze, 1880 (Porifera, Plakinidae) from the Aleutian Islands (Alaska, USA) SO ZOOTAXA LA English DT Article DE taxonomy; Porifera; Plakinidae; new species; Aleutian Islands; N-Pacific ID HOMOSCLEROMORPHA; DEMOSPONGIAE AB Plakina tanaga and Plakina atka n. spp. are described from the waters around the Aleutian Islands at depths between 118 and 146m. These are the first records of the genus from the Aleutian Islands. The new species described here are compared with the six species of Plakina previously reported from the Pacific. Both species belong to the Plakina trilopha species-complex and differ from other Pacific species of Plakina in their conspicuous convoluted surface pattern, color, and spiculation. In addition to the usual set of triods both species have a second category with basally spined rays. Plakina tanaga n. sp. has a strongly convoluted, microtuberculate surface, and a few small, thin spines at the basal rays of the triods, and relatively large trilophose calthrops. Plakina atka n. sp. has a smoother surface, more numerous larger and thicker basal spines at the triods, and considerably smaller lophocalthrops which are tetralophate. C1 Natl Marine Fisheries Serv, Auke Bay Lab, Juneau, AK 99801 USA. Inst Zool 1, D-91054 Erlangen, Germany. RP Lehnert, H (reprint author), Eichenstr 14, D-86507 Oberottmarshausen, Germany. EM Helm.Lehnert@t-online.de NR 11 TC 10 Z9 10 U1 1 U2 2 PU MAGNOLIA PRESS PI AUCKLAND PA PO BOX 41383, AUCKLAND, ST LUKES 1030, NEW ZEALAND SN 1175-5326 EI 1175-5334 J9 ZOOTAXA JI Zootaxa PD OCT 21 PY 2005 IS 1068 BP 27 EP 38 PG 12 WC Zoology SC Zoology GA 975XK UT WOS:000232697200002 ER PT J AU Brown, SW Johnson, BC Biggar, SF Zalewski, EF Cooper, J Hajek, P Hildum, E Grant, P Barnes, RA Butler, JJ AF Brown, SW Johnson, BC Biggar, SF Zalewski, EF Cooper, J Hajek, P Hildum, E Grant, P Barnes, RA Butler, JJ TI Radiometric validation of NASA's Ames Research Center's Sensor Calibration Laboratory SO APPLIED OPTICS LA English DT Article ID EARTH OBSERVING SYSTEM; INTEGRATING SPHERE SOURCE; REFLECTANCE; SUPPORT; REFLECTOMETER; RADIANCE; PROGRAM; MODIS AB The National Aeronautics and Space Administration's (NASA's) Ames Research Center's Airborne Sensor Facility (ASF) is responsible for the calibration of several airborne Earth-viewing sensor systems in support of NASA Earth Observing System (EOS) investigations. The primary artifact used to calibrate these sensors in the reflective solar region from 400 to 2500 nm is a lamp-illuminated integrating sphere source. In September 1999, a measurement comparison was made at the Ames ASF Sensor Calibration Facility to validate the radiometric scale, establish the uncertainties assigned to the radiance of this source, and examine its day-to-day repeatability. The comparison was one of a series of validation activities overseen by the EOS Calibration Program to ensure the radiometric calibration accuracy of sensors used in long-term, global, remote-sensing studies. Results of the comparison, including an evaluation of the Ames Sensor Calibration Laboratory (SCL) measurement procedures and assigned radiometric uncertainties, provide a validation of their radiometric scale at the time of the comparison. Additionally, the maintenance of the radiance scale was evaluated by use of independent, long-term, multiyear radiance validation measurements of the Ames sphere source. This series of measurements provided an independent assessment of the radiance values assigned to integrating sphere sources by the Ames SCF. Together, the measurements validate the SCF radiometric scale and assigned uncertainties over the time period from September 1999 through July 2003. (c) 2005 Optical Society of America C1 NIST, Gaithersburg, MD 20899 USA. Univ Arizona, Remote Sensing Grp, Tucson, AZ 85721 USA. Sci Syst Appl Inc, Lanham, MD 20706 USA. Sci Applicat Int Corp, Moffett Field, CA 94035 USA. Sci Applicat Int Corp, Beltsville, MD 20705 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Brown, SW (reprint author), NIST, Gaithersburg, MD 20899 USA. EM rbarnes@seawifs.gsfc.nasa.gov RI Butler, James/D-4188-2013 NR 26 TC 7 Z9 7 U1 0 U2 0 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 OCT 20 PY 2005 VL 44 IS 30 BP 6426 EP 6443 DI 10.1364/AO.44.006426 PG 18 WC Optics SC Optics GA 975PR UT WOS:000232674900014 PM 16252654 ER PT J AU De Marco, O Shara, MM Zurek, D Ouellette, JA Lanz, T Saffer, RA Sepinsky, JF AF De Marco, O Shara, MM Zurek, D Ouellette, JA Lanz, T Saffer, RA Sepinsky, JF TI A spectroscopic analysis of blue stragglers, horizontal branch stars, and turnoff stars in four globular clusters SO ASTROPHYSICAL JOURNAL LA English DT Article DE blue stragglers; globular clusters : individual (47 Tucanae,M3,NGC 6397,NGC 6752); methods : data analysis; methods : numerical; stars : fundamental parameters; techniques : spectroscopic ID ALPHA-ELEMENT ABUNDANCES; HUBBLE-SPACE-TELESCOPE; METAL-POOR STARS; STELLAR COLLISIONS; MODEL ATMOSPHERES; PHOTOMETRY; NGC-6397; TUCANAE; 47-TUC; CORE AB We present a spectroscopic analysis of HST STIS and FOS low- and intermediate-resolution spectroscopy of 55 stars in four globular clusters ( 47 Tucanae, M3, NGC 6752, and NGC 6397). Stars hotter than T-eff = 5750 K and with a signal-to-noise ratio larger than 15 were analyzed with non-local thermodynamic equilibrium model atmospheres, and values for their effective temperatures and gravities were obtained. Using photometric fluxes, we also obtained radii, luminosities, and spectroscopic masses. Twenty-four stars in our sample are blue stragglers (BSs). Their photometric colors and magnitudes place these BSs above and redward of the clusters' zero-age main sequence: this is consistent with the gravities we find for these stars, which are lower than zero-age main-sequence gravities. A comparison with stellar evolutionary tracks shows that almost all of our BSs are in the Hertzsprung gap. This is contrary to theory, because of the short timescale expected for stars in this evolutionary phase. The mean BS mass is 1.04M(circle dot) for 14 nonvariable stars, or 1.07 M-circle dot counting all 24 BSs in our sample. For the nonvariable stars the mean BS masses for individual clusters are 1.73, 1.01, 0.95, and 0.72 M-circle dot for NGC 6397, NGC 6752, 47 Tuc, and M3, respectively. Adding the variable stars ( which improves the statistics but increases the uncertainty), the mean masses become 1.27, 1.05, 0.99, and 0.99 M-circle dot, respectively. Although there is considerable scatter, the BS spectroscopic masses correlate with both effective temperature and brightness of the stars, as expected. The mean nonvariable turnoff star mass ( 0.58 M-circle dot) is significantly below the values determined for the BSs and below the main-sequence turnoff mass. The mean nonvariable horizontal-branch (HB) star mass is higher than expected (0.79 M-circle dot). In particular, several HB stars have masses well above the main-sequence turnoff mass. Some of these HB stars are suspected of actually being BSs, since most of them reside at ambiguous locations on the CMD, making them prone to misclassification. Values and limits to the stellar rotation rates (v sin i) are imposed by fitting weak metal lines, the Ca II K line wings, or the helium lines for the hotter stars. Five BSs with reasonably constrained rotations show average and median v sin i values of 109 and 100 km s(-1), respectively, suggesting v similar to 160 km s(-1). At least some GC BSs are very rapid rotators, but this information cannot yet constrain their origin as stellar collision or binary mergers because of the lack of clear theoretical predictions. Six extreme HB stars have rotation rates v sin i between 50 and 200 km s(-1), which are high for these stars and might indicate a binary origin. De Marco et al. found that four BSs and two HB stars in our sample have Balmer jumps that are too large for the effective temperatures implied by the slopes of their Paschen continua. Two additional HB stars are now identified in the current study as having the same feature. For these stars, the presence of a disk of partly ionized material is suspected, although high stellar rotation rates could also partly explain the data. C1 Amer Museum Nat Hist, Dept Astrophys, New York, NY 10024 USA. Univ Maryland, Dept Astron, College Pk, MD 20742 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Villanova Univ, UNIT Cent Serv, Villanova, PA 19085 USA. Villanova Univ, Dept Astron & Astrophys, Villanova, PA 19085 USA. RP De Marco, O (reprint author), Amer Museum Nat Hist, Dept Astrophys, New York, NY 10024 USA. OI Sepinsky, Jeremy/0000-0001-8085-3836 NR 49 TC 34 Z9 34 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 OCT 20 PY 2005 VL 632 IS 2 BP 894 EP 919 DI 10.1086/444372 PN 1 PG 26 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 974CO UT WOS:000232569100021 ER PT J AU Sloan, GC Keller, LD Forrest, WJ Leibensperger, E Sargent, B Li, A Najita, J Watson, DM Brandl, BR Chen, CH Green, JD Markwick-Kemper, F Herter, TL D'Alessio, P Morris, PW Barry, DJ Hall, P Myers, PC Houck, JR AF Sloan, GC Keller, LD Forrest, WJ Leibensperger, E Sargent, B Li, A Najita, J Watson, DM Brandl, BR Chen, CH Green, JD Markwick-Kemper, F Herter, TL D'Alessio, P Morris, PW Barry, DJ Hall, P Myers, PC Houck, JR TI Mid-infrared spectra of polycyclic aromatic hydrocarbon emission in herbig Ae/Be stars SO ASTROPHYSICAL JOURNAL LA English DT Article DE infrared : stars; stars : chemically peculiar ID DIFFUSE INTERSTELLAR-MEDIUM; INFRARED SPECTROGRAPH IRS; SPITZER-SPACE-TELESCOPE; CIRCUMSTELLAR DISK; ISO SPECTROSCOPY; DUST; MOLECULES; FEATURES; PAHS; TEMPERATURES AB We present spectra of four Herbig Ae/Be stars obtained with the Infrared Spectrograph (IRS) on the Spitzer Space Telescope. All four of the sources show strong emission from polycyclic aromatic hydrocarbons (PAHs), with the 6.2 mu m emission feature shifted to 6.3 mu m and the strongest C-C skeletal-mode feature occurring at 7.9 mu m instead of at 7.7 mu m, as is often seen. Remarkably, none of the four stars has silicate emission. The strength of the 7.9 mu m feature varies with respect to the 11.3 mu m feature among the sources, indicating that we have observed PAHs with a range of ionization fractions. The ionization fraction is higher for systems with hotter and brighter central stars. Two sources, HD 34282 and HD 169142, show emission features from aliphatic hydrocarbons at 6.85 and 7.25 mu m. The spectrum of HD 141569 shows a previously undetected emission feature at 12.4 mu m that may be related to the 12.7 mu m PAH feature. The spectrum of HD 135344, the coolest star in our sample, shows an unusual profile in the 7-9 mu m region, with the peak emission to the red of 8.0 mu m and no 8.6 mu m PAH feature. C1 Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. Ithaca Coll, Dept Phys, Ithaca, NY 14850 USA. Univ Rochester, Dept Phys & Astron, Rochester, NY 14627 USA. Univ Missouri, Dept Phys & Astron, Columbia, MO 65211 USA. Natl Opt Astron Observ, Tucson, AZ 85719 USA. Sterrewacht Leiden, NL-2300 RA Leiden, Netherlands. Univ Virginia, Dept Astron, Charlottesville, VA 22903 USA. Univ Nacl Autonoma Mexico, Ctr Radioastron & Astrofis, Morelia 58089, Michoacan, Mexico. CALTECH, Ctr Infrared Proc & Anal, NASA, Herschel Sci Ctr, Pasadena, CA 91125 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Sloan, GC (reprint author), Cornell Univ, Dept Astron, 610 Space Sci Bldg, Ithaca, NY 14853 USA. EM sloan@isc.astro.cornell.edu RI Kemper, Francisca/D-8688-2011 OI Kemper, Francisca/0000-0003-2743-8240 NR 55 TC 78 Z9 78 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 20 PY 2005 VL 632 IS 2 BP 956 EP 963 DI 10.1086/444371 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 974CO UT WOS:000232569100025 ER PT J AU Gogus, E Patel, SK Wilson, CA Woods, PM Finger, MH Kouveliotou, C AF Gogus, E Patel, SK Wilson, CA Woods, PM Finger, MH Kouveliotou, C TI Chandra localization of XTE J1906+090 and discovery of its optical and infrared counterparts SO ASTROPHYSICAL JOURNAL LA English DT Article DE infrared : stars; pulsars : individual ( XTE J1906+090); X-rays : binaries ID X-RAY PULSAR; XTE J1906+09; EXTINCTION; ACCRETION; BINARY; STARS; SAX-J2103.5+4545; GALAXY AB We present the Chandra identification and localization of the transient X-ray source XTE J1906+090 and the discovery of its optical and infrared counterparts. Our analysis of archival Chandra ACIS-I observations of the field found the source approximately 80 away from the position determined earlier with the RXTE PCA. We have confirmed the source identification with timing analysis of the X-ray data, which detected the source spin period of 89.6 s. The best Chandra position for the source is R.A. = 19(h)04(m)47(s).491, decl = +09 degrees 02'41."40. Subsequently, we performed optical observations of the field around the new location and discovered a coincident optical source with R-band magnitude of 18.7. A search in the Two Micron All Sky Survey catalog revealed an infrared point source with J = 15.2, H = 14.2, and K = 13.5, whose location is also coincident with our Chandra and optical positions. Our results add fresh evidence for a Be/X-ray transient nature for XTE J1906+090. C1 Sabanci Univ, Fac Engn & Nucl Sci, TR-34956 Istanbul, Turkey. Univ Space Res Assoc, Seabrook, MD 20706 USA. Natl Space Sci & Technol, Space Sci Branch, Huntsville, AL 35805 USA. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Gogus, E (reprint author), Sabanci Univ, Fac Engn & Nucl Sci, Orhanli Tuzla, TR-34956 Istanbul, Turkey. EM ersing@sabanciuniv.edu NR 28 TC 2 Z9 2 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 OCT 20 PY 2005 VL 632 IS 2 BP 1069 EP 1074 DI 10.1086/444373 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 974CO UT WOS:000232569100037 ER PT J AU Seager, S Richardson, LJ Hansen, BMS Menou, K Cho, JYK Deming, D AF Seager, S Richardson, LJ Hansen, BMS Menou, K Cho, JYK Deming, D TI On the dayside thermal emission of hot jupiters SO ASTROPHYSICAL JOURNAL LA English DT Article DE planetary systems ID EXTRASOLAR GIANT PLANETS; B-LIKE PLANETS; HD 209458B; TRANSITING PLANET; ATMOSPHERES; TRES-1; SOLAR; SPECTROGRAPH; ABSORPTION; PHOTOMETRY AB We discuss atmosphere models of HD 209458b in light of the recent dayside flux measurement of HD 209458b's secondary eclipse by Spitzer MIPS at 24 mu m. In addition, we present a revised secondary eclipse IRTF upper limit at 2.2 mu m that places a stringent constraint on the adjacent H2O absorption band depths. These two measurements are complementary because they are both shaped by H2O absorption and because the former is on the Wien tail of the planet's thermal emission spectrum and the latter is near the thermal emission peak. A wide range of models fit the observational data, confirming our basic understanding of hot Jupiter atmospheric physics. Although a range of models are viable, some models at the hot and cold end of the plausible temperature range can be ruled out. One class of previously unconsidered hot Jupiter atmospheric models that fit the data are those with C/O greater than or similar to 1 ( as Jupiter may have), which have a significant paucity of H2O compared to solar abundance models with C/O greater than or similar to 0.5. The models indicate that HD 209458b is in a situation intermediate between pure in situ reradiation and very efficient redistribution of heat, one that will require a careful treatment of atmospheric circulation. We discuss how future wavelength- and phase-dependent observations will further constrain the atmospheric circulation regime. In the shorter term, additional planned measurements for HD 209458b, especially Spitzer IRAC photometry, should lift many of the model degeneracies. Multiwavelength IR observations constrain the atmospheric structure and circulation properties of hot Jupiters and thus open a new chapter in quantitative extrasolar planetology. C1 Carnegie Inst Washington, Dept Terr Magnetism, Washington, DC 20015 USA. NASA, Goddard Space Flight Ctr, Exoplanets & Stellar Astrophys Lab, Greenbelt, MD 20771 USA. Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. Columbia Univ, Dept Astron, New York, NY 10027 USA. NASA, Goddard Space Flight Ctr, Planetary Syst Lab, Greenbelt, MD 20771 USA. RP Seager, S (reprint author), Carnegie Inst Washington, Dept Terr Magnetism, 5241 Broad Branch Rd NW, Washington, DC 20015 USA. NR 47 TC 96 Z9 99 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 OCT 20 PY 2005 VL 632 IS 2 BP 1122 EP 1131 DI 10.1086/444411 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 974CO UT WOS:000232569100044 ER PT J AU Wittenmyer, RA Welsh, WF Orosz, JA Schultz, AB Kinzel, W Kochte, M Bruhweiler, F Bennum, D Henry, GW Marcy, GW Fischer, DA Butler, RP Vogt, SS AF Wittenmyer, RA Welsh, WF Orosz, JA Schultz, AB Kinzel, W Kochte, M Bruhweiler, F Bennum, D Henry, GW Marcy, GW Fischer, DA Butler, RP Vogt, SS TI System parameters of the transiting extrasolar planet HD 209458b SO ASTROPHYSICAL JOURNAL LA English DT Article DE planetary systems; stars : individual ( HD 209458) ID B-LIKE PLANETS; G-TYPE STARS; LATE A-TYPE; GIANT PLANETS; LUMINOSITY CLASSIFICATION; EFFECTIVE TEMPERATURES; PHYSICAL BASIS; BROWN DWARFS; F-TYPE; PHOTOMETRY AB We derive improved system parameters for the HD 209458 system using a model that simultaneously fits both photometric transit and radial velocity observations. The photometry consists of previous Hubble Space Telescope STIS and FGS observations, 12 I-band transits observed between 2001 and 2003 with the Mount Laguna Observatory 1 m telescope, and six Stromgren b + y transits observed between 2001 and 2004 with two of the Automatic Photometric Telescopes at Fairborn Observatory. The radial velocities were derived from Keck HIRES observations. The model properly treats the orbital dynamics of the system and thus yields robust and physically self-consistent solutions. Our set of system parameters agrees with previously published results, although with improved accuracy. For example, applying robust limits on the stellar mass of 0.93 - 1.20 M-circle dot, we find 1.26R(J) < R-planet < 1.42R(J) and 0.59M(J) < M-planet < 0.70M(J). We can reduce the uncertainty of these estimates by including a stellar mass-radius relation constraint, yielding R-planet (1.35 +/- 0.07)R-J and M-planet = (0.66 +/- 0.04)M-J. Our results verify that the planetary radius is 10%-20% larger than predicted by irradiated planet evolution models, confirming the need for an additional mechanism to slow the evolutionary contraction of the planet. A revised ephemeris is derived, T-0 = 2, 452; 854.82545 + 3.52474554E (HJD), which now contains an uncertainty in the period of 0.016 s and should facilitate future searches for planetary satellites and other bodies in the HD 209458 system. C1 San Diego State Univ, Dept Astron, San Diego, CA 92182 USA. Comp Sci Corp, Sci Program, Baltimore, MD 21218 USA. Space Telescope Sci Inst, Sci Program, Baltimore, MD 21218 USA. Catholic Univ Amer, Dept Phys, Inst Astrophys & Computat Sci, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Nevada, Dept Phys, Reno, NV 89557 USA. Tennessee State Univ, Ctr Excellence Informat Syst, Nashville, TN 37203 USA. Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Carnegie Inst Washington, Dept Terr Magnetism, Washington, DC 20015 USA. Univ Calif Santa Cruz, Lick Observ, Santa Cruz, CA 95064 USA. RP Wittenmyer, RA (reprint author), Univ Texas, Dept Astron, 1 Univ Stn,C1400, Austin, TX 78712 USA. EM robw@astro.as.utexas.edu; wfw@sciences.sdsu.edu; orosz@sciences.sdsu.edu RI Butler, Robert/B-1125-2009; OI Fischer, Debra/0000-0003-2221-0861 NR 56 TC 50 Z9 50 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 OCT 20 PY 2005 VL 632 IS 2 BP 1157 EP 1167 DI 10.1086/433176 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 974CO UT WOS:000232569100047 ER PT J AU Brosius, JW Landi, E AF Brosius, JW Landi, E TI Properties of a sunspot plume observed with the coronal diagnostic spectrometer aboard the Solar and Heliospheric Observatory SO ASTROPHYSICAL JOURNAL LA English DT Article DE sun : activity; sun : corona; sunspots; sun : transition region; sun : UV radiation ID EXTREME-ULTRAVIOLET OBSERVATIONS; OPTICALLY THIN PLASMAS; TRANSITION REGION; ACTIVE-REGION; LINE INTENSITIES; ATOMIC DATABASE; EMISSION-LINES; SOHO; RADIO; OSCILLATIONS AB We used three instruments (CDS, EIT, MDI) aboard the Solar and Heliospheric Observatory spacecraft to observe the large sunspot in NOAA Active Region 8539 on 1999 May 9 and 13. The spot contained a bright plume, most easily seen in EUV emission lines formed at 5.2 less than or similar to log T less than or similar to 5.7 (where T is the temperature in K), in its umbra on both dates. The plume's differential emission measure (DEM) exhibited one and only one broad peak, centered around log T similar to 5.8 on May 9 and around log T similar to 5.6 on May 13, and exceeded the DEM of the quiet Sun by more than an order of magnitude at these temperatures. The high-temperature portion of the plume's DEM resembled that of nearby quiet-Sun areas. Intensity ratios of the O(IV) lines at 625.8 and 554.5 angstrom yield log n(e) (where ne is the electron density in cm(-3)) of 9.6(-0.6)(+0.3) in the plume on May 9 and 9.7(-0.2)(+0.2) on May 13; values of 9.4(-0.9)(+0.3) and 9.4(-0.3)(+0.2) were obtained in the quiet-Sun areas on the same dates. Based on abundance enhancements derived from transition region emission lines of Ca, an element with low first ionization potential, elemental abundances in the plume appear to be coronal rather than photospheric. The plume plasma reveals a bipolar Doppler velocity flow pattern, in which maximum downflows in excess of 37 km s(-1) are observed in the northeast portion of the plume, and maximum upflows that exceed 52 km s(-1) are observed in the northwest. C1 Catholic Univ Amer, NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. USN, Res Lab, Artep Inc, Washington, DC 20375 USA. RP Brosius, JW (reprint author), Catholic Univ Amer, NASA, Goddard Space Flight Ctr, Code 612-1, Greenbelt, MD 20771 USA. RI Landi, Enrico/H-4493-2011 NR 45 TC 11 Z9 11 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 OCT 20 PY 2005 VL 632 IS 2 BP 1196 EP 1203 DI 10.1086/444452 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 974CO UT WOS:000232569100051 ER PT J AU Friedel, DN Snyder, LE Remijan, AJ Turner, BE AF Friedel, DN Snyder, LE Remijan, AJ Turner, BE TI Detection of interstellar acetone toward the Orion-KL hot core SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : individual (Orion-KL); ISM : molecules; radio lines : ISM ID DIMETHYL ETHER; LINE SURVEY; GHZ; GLYCINE AB We present the first detection of interstellar acetone [(CH3)(2)CO] toward the high-mass star-forming region Orion-KL and the first detection of vibrationally excited (CH3)(2) CO in the interstellar medium (ISM). Using the BIMA array, 28 emission features that can be assigned to 54 acetone transitions were detected. Furthermore, 37 of these transitions have not been previously observed in the ISM. The observations also show that the acetone emission is concentrated toward the hot core region of Orion-KL, contrary to the distribution of other large oxygen-bearing molecules. From our rotational temperature diagram, we find a beam-averaged (CH3)(2) CO column density of [2.0(0.3)-8.0(1.2)] x 10(16) cm(-2) and a rotational temperature of 176(48)-194(66) K. C1 Univ Illinois, Dept Astron, Urbana, IL 61801 USA. NASA, Goddard Space Flight Ctr, Computat & Informat Sci & Technol Off, Greenbelt, MD 20771 USA. Natl Radio Astron Observ, Charlottesville, VA 22903 USA. RP Friedel, DN (reprint author), Univ Illinois, Dept Astron, 1002 W Green St, Urbana, IL 61801 USA. EM friedel@astro.uiuc.edu; snyder@astro.uiuc.edu; aremijan@pop900.gsfc.nasa.gov; bturner@nrao.edu NR 20 TC 31 Z9 31 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 OCT 20 PY 2005 VL 632 IS 2 BP L95 EP L98 DI 10.1086/497986 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 974CR UT WOS:000232569400010 ER PT J AU Gelbord, JM Marshall, HL Worrall, DM Birkinshaw, M Lovell, JEJ Ojha, R Godfrey, L Schwartz, DA Perlman, ES Georganopoulos, M Murphy, DW Jauncey, DL AF Gelbord, JM Marshall, HL Worrall, DM Birkinshaw, M Lovell, JEJ Ojha, R Godfrey, L Schwartz, DA Perlman, ES Georganopoulos, M Murphy, DW Jauncey, DL TI The knotty question of the jet of PKSB1421-490 SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : jets; quasars : individual (PKS B1421-490) ID BL LACERTAE OBJECTS; DIGITAL SKY SURVEY; X-RAY-EMISSION; CATALOG; SAMPLE; MULTIWAVELENGTH; M87 AB We report the discovery of unusually strong optical and X-ray emission associated with a knot in the radio jet of PKS B1421-490. The knot is the brightest feature observed beyond the radio band, with knot/core flux ratios similar to 300 and 3.7 at optical and X-ray frequencies, respectively. We interpret the extreme optical output of the knot as synchrotron emission. The nature of the X-ray emission is unclear. We consider a second synchrotron component, inverse Compton emission from a relativistic, decelerating jet, and the possibility that this feature is a chance superposition of an unusual BL Lac object. C1 MIT, Kavli Inst Astrophys & Space Res, Cambridge, MA 02139 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Bristol, Dept Phys, Bristol BS8 1TL, Avon, England. Commonwealth Sci & Ind Res Org, Australia Telescope Natl Facil, Epping, NSW 2122, Australia. Australian Natl Univ, Res Sch Astron & Astrophys, Canberra, ACT 72611, Australia. Univ Maryland Baltimore Cty, Joint Ctr Astrophys, Baltimore, MD 21250 USA. Univ Maryland Baltimore Cty, Dept Phys, Baltimore, MD 21250 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Gelbord, JM (reprint author), MIT, Kavli Inst Astrophys & Space Res, 77 Massachusetts Ave, Cambridge, MA 02139 USA. EM jonathan@space.mit.edu; hermanm@space.mit.edu; d.worrall@bristol.ac.uk; mark.birkinshaw@bristol.ac.uk; jim.lovell@csiro.au; roopesh.ojha@csiro.au; lgodfrey@mso.anu.edu.au; das@head-cfa.harvard.edu; perlman@jca.umbc.edu; markos@milkyway.gsfc.nasa.gov; dwm@sgra.jpl.nasa.gov; david.jauncey@csiro.au RI Godfrey, Leith/B-5283-2013 NR 28 TC 5 Z9 5 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 OCT 20 PY 2005 VL 632 IS 2 BP L75 EP L78 DI 10.1086/497823 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 974CR UT WOS:000232569400005 ER PT J AU Immler, S Kuntz, KD AF Immler, S Kuntz, KD TI Discovery of X-ray emission from supernova 1970G with Chandra: Filling the void between supernovae and supernova remnants SO ASTROPHYSICAL JOURNAL LA English DT Article DE circumstellar matter; supernova remnants; supernovae : individual (SN 1970G); X-rays : general; X-rays : individual (SN 1970G, M101) ID RADIO OBSERVATIONS; II SUPERNOVAE; SN 1993J; M101; POPULATION; EVOLUTION; GALAXY AB We report the discovery of X-ray emission from SN 1970G in M101, 35 yr after its outburst, using deep X-ray imaging with the Chandra X-Ray Observatory. The Chandra ACIS spectrum shows that the emission is soft (less than or similar to 2 keV) and characteristic of the reverse-shock region. The X-ray luminosity, L0.3-2 = (1.1 +/- 0.2) x 10(37) ergs s(-1), is likely caused by the interaction of the supernova shock with dense circumstellar matter. If the material was deposited by the stellar wind from the progenitor, a mass-loss rate of <(M)over dot> = (2.6 +/- 0.4) x 10(-5) M circle dot yr(-1) (v(w)/10 is inferred. Utilizing the high-resolution Chandra ACIS data of SN 1970G and its environment, we reconstruct the X- ray lightcurve from previous ROSAT HRI, PSPC, and XMM- Newton EPIC observations, and find a best-fit linear rate of decline of L proportional to t(-s) with index s = 2.7 +/- 0.9 over a period of approximate to 20-35 yr after the outburst. As the oldest supernova detected in X- rays, SN 1970G allows, for the first time, direct observation of the transition from a supernova to its supernova remnant phase. C1 NASA, Goddard Space Flight Ctr, Explorat Univ Div, Xray Asrtrophys Lab, Greenbelt, MD 20771 USA. Univ Space Res Assoc, Columbia, MD 21044 USA. Johns Hopkins Univ, Henry A Rowland Dept Phys & Astron, Baltimore, MD 21218 USA. RP Immler, S (reprint author), NASA, Goddard Space Flight Ctr, Explorat Univ Div, Xray Asrtrophys Lab, Code 662, Greenbelt, MD 20771 USA. NR 24 TC 27 Z9 27 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 OCT 20 PY 2005 VL 632 IS 2 BP L99 EP L102 DI 10.1086/497910 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 974CR UT WOS:000232569400011 ER PT J AU Kimura, Y Nuth, JA Ferguson, FT AF Kimura, Y Nuth, JA Ferguson, FT TI Is the 21 micron feature observed in some post-AGB stars caused by the interaction between Ti atoms and fullerenes? SO ASTROPHYSICAL JOURNAL LA English DT Article DE infrared : stars; methods : laboratory; stars : AGB and post-AGB; stars : carbon; stars : mass loss ID GIANT BRANCH STARS; EMISSION FEATURE; CARBIDE; GRAINS; SPECTROSCOPY; CARRIER; NANOPARTICLES; CARBON; SYSTEM; C-60 AB Recent measurements of fullerenes and Ti atoms recorded in our laboratory have demonstrated the presence of an infrared feature near 21 mu m. The feature observed has nearly the same shape and position as is observed for one of the most enigmatic features in post-asymptotic giant branch (AGB) stars. In our experimental system, large-cage carbon particles, such as large fullerenes, were produced from CO gas by the Boudouard reaction. Large-cage carbon particles intermixed with Ti atoms were produced by the evaporation of a Ti-metal-wrapped carbon electrode in CO gas. The infrared spectra of large fullerenes interacting with Ti atoms show a characteristic feature at 20.3 mu m that closely corresponds to the 20.1 mu m feature observed in post-AGB stars. Both the laboratory and stellar spectra also show a small but significant peak at 19.0 mu m, which is attributed to fullerenes. Here we propose that the interaction between fullerenes and Ti atoms may be a plausible explanation for the 21 mu m feature seen in some post-AGB stars. C1 NASA, Goddard Space Flight Ctr, Astrochem Lab, Solar Syst Explorat Div, Greenbelt, MD 20771 USA. Catholic Univ Amer, Dept Chem, Washington, DC 20064 USA. RP Kimura, Y (reprint author), NASA, Goddard Space Flight Ctr, Astrochem Lab, Solar Syst Explorat Div, Code 691, Greenbelt, MD 20771 USA. EM ykimura@ssedmail.gsfc.nasa.gov; Joseph.A.Nuth@nasa.gov; Frank.Ferguson@gsfc.nasa.gov RI Ferguson, Frank/C-9493-2012; Nuth, Joseph/E-7085-2012; Kimura, Yuki/J-9635-2014 OI Kimura, Yuki/0000-0002-9218-7663 NR 19 TC 12 Z9 12 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 OCT 20 PY 2005 VL 632 IS 2 BP L159 EP L162 DI 10.1086/497987 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 974CR UT WOS:000232569400026 ER PT J AU Strohmayer, TE Watts, AL AF Strohmayer, TE Watts, AL TI Discovery of fast X-ray oscillations during the 1998 giant flare from SGR 1900+14 SO ASTROPHYSICAL JOURNAL LA English DT Article DE pulsars : individual (SGR 1900+14); stars : magnetic fields; stars : neutron; stars : oscillations; stars : rotation; X-rays : stars ID SOFT GAMMA-REPEATERS; NEUTRON-STARS; TORSIONAL OSCILLATIONS; RADIATIVE MECHANISM; AUGUST 27; SGR-1806-20; BURST; SGR1900+14; EVOLUTION; BEPPOSAX AB We report the discovery of complex high-frequency variability during the 1998 August 27 giant flare from SGR 1900 + 14 using the Rossi X-Ray Timing Explorer (RXTE). We detect an approximate to 84 Hz quasi-periodic oscillation (QPO) during a 1 s interval beginning approximately 1 minute after the initial hard spike. The amplitude is energy-dependent, reaching a maximum of 26% (rms) for photons above 30 keV and is not detected below 11 keV, with a 90% confidence upper limit of 14% (rms). Remarkably, additional QPOs are detected in the average power spectrum of data segments centered on the rotational phase at which the 84 Hz signal was detected. Two signals, at 53.5 and 155.1 Hz, are strongly detected, while a third feature at 28 Hz is found with lower significance. These QPOs are not detected at other rotational phases. The phenomenology seen in the SGR 1900 + 14 flare is similar to that of QPOs recently reported by Israel et al. from the 2004 December 27 flare from SGR 1806-20, suggesting that they may have a common origin, perhaps torsional vibrations of the neutron star crust. Indeed, an association of the four frequencies (in increasing order) found in SGR 1900 + 14 with l = 2, 4, 7, and 13 toroidal modes appears plausible. We discuss our findings in the context of this model and show that if the stars have similar masses, then the magnetic field in SGR 1806 - 20 must be about twice as large as in SGR 1900 + 14, broadly consistent with estimates from pulse timing. We briefly discuss how mode identifications could lead to constraints on the nuclear equation of state. C1 NASA, Goddard Space Flight Ctr, Explorat Univ Div, Greenbelt, MD 20771 USA. NRC, Goddard Space Flight Ctr, Explorat Univ Div, Greenbelt, MD 20771 USA. RP Strohmayer, TE (reprint author), NASA, Goddard Space Flight Ctr, Explorat Univ Div, Greenbelt, MD 20771 USA. EM stroh@milkyway.gsfc.nasa.gov; anna@milkyway.gsfc.nasa.gov NR 23 TC 140 Z9 140 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 OCT 20 PY 2005 VL 632 IS 2 BP L111 EP L114 DI 10.1086/497911 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 974CR UT WOS:000232569400014 ER PT J AU Tucker, CJ Pinzon, JE Brown, ME Slayback, DA Pak, EW Mahoney, R Vermote, EF El Saleous, N AF Tucker, CJ Pinzon, JE Brown, ME Slayback, DA Pak, EW Mahoney, R Vermote, EF El Saleous, N TI An extended AVHRR 8-km NDVI dataset compatible with MODIS and SPOT vegetation NDVI data SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article ID HIGH-RESOLUTION RADIOMETER; LAND DATA SET; GLOBAL DATA; INDEX DATA; MAUNA-LOA; PINATUBO; CHANNELS; AEROSOL; CALIBRATION; SPACECRAFT AB Daily daytime Advanced Very High Resolution Radiometer (AVHRR) 4-km global area coverage data have been processed to produce a Normalized Difference Vegetation Index (NDVI) 8-km equal-area dataset from July 1981 through December 2004 for all continents except Antarctica. New features of this dataset include bimonthly composites, NCIAA-9 descending node data from August 1994 to January 1995, volcanic stratospheric aerosol correction for 19821984 and 1991-1993, NDVI normalization using empirical mode decomposition/ reconstruction to minimize varying solar zenith angle effects introduced by orbital drift, inclusion of data from NOAA-16 for 2000-2003 and NOAA-17 for 2003-2004, and a similar dynamic range with the MODIS NDVI. Two NDVI compositing intervals have been produced: a bimonthly global dataset and a 10-day Africa-only dataset. Post-processing review corrected the majority of dropped scan lines, navigation errors, data drop outs, edge-of-orbit composite discontinuities, and other artefacts in the composite NDVI data. All data are available from the University of Maryland Global Land Cover Facility (http:// glcf.umiacs.umd.edu/data/gimms/). C1 NASA, Goddard Space Flight Ctr, Terr Phys Lab, Biospher Sci Branch, Greenbelt, MD 20771 USA. RP Brown, ME (reprint author), NASA, Goddard Space Flight Ctr, Terr Phys Lab, Biospher Sci Branch, Code 923, Greenbelt, MD 20771 USA. EM molly.brown@gsfc.nasa.gov RI Brown, Molly/E-2724-2010; Slayback, Daniel/E-7465-2011; Vermote, Eric/K-3733-2012; Brown, Molly/M-5146-2013 OI Brown, Molly/0000-0001-7384-3314; Brown, Molly/0000-0001-7384-3314 NR 46 TC 982 Z9 1093 U1 26 U2 208 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD OCT 20 PY 2005 VL 26 IS 20 BP 4485 EP 4498 DI 10.1080/01431160500168686 PG 14 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA 992UM UT WOS:000233909500007 ER PT J AU Rinsland, CP Dufour, G Boone, CD Bernath, PF Chiou, L AF Rinsland, CP Dufour, G Boone, CD Bernath, PF Chiou, L TI Atmospheric Chemistry Experiment (ACE) measurements of elevated Southern Hemisphere upper tropospheric CO, C2H6, HCN, and C2H2 mixing ratios from biomass burning emissions and long-range transport SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID CARBON-MONOXIDE; WESTERN PACIFIC; TROPICS; OZONE; AEROSOL; GASES; OCEAN; BASIN AB Infrared Fourier transform spectra recorded at 0.02 cm(-1) resolution by the Atmospheric Chemistry Experiment (ACE) show elevated levels of the relatively long-lived biomass burning products CO, C2H6, HCN, and C2H2 in the upper troposphere and lower stratosphere at 15 degrees S-45 degrees S latitude from 30 September to 3 November 2004. Mixing ratios up to 260 ppbv (10(-9) per unit volume) for CO, 1470 pptv (10(-12) per unit volume) for HCN, and 1.67 ppbv for C2H6 are observed in the upper troposphere and their variations are highly correlated reflecting their similar lifetimes and emission origin. Back trajectory calculations and maps of fire distributions for the time period indicate the elevated levels likely originated from regions of tropical fire emissions in South America or Africa with cases identified with elevated emissions reaching close to the lower stratosphere. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. Univ Waterloo, Dept Chem, Waterloo, ON N2L 3G1, Canada. Sci Applicat Int Corp, Hampton, VA 23666 USA. RP Rinsland, CP (reprint author), NASA, Langley Res Ctr, Mail Stop 401A, Hampton, VA 23681 USA. EM c.p.rinsland@larc.nasa.gov; gdufour@acebox.uwaterloo.ca; cboone@acebox.uwaterloo.ca; bernath@uwaterloo.ca; l.s.chiou@larc.nasa.gov RI Bernath, Peter/B-6567-2012 OI Bernath, Peter/0000-0002-1255-396X NR 27 TC 33 Z9 33 U1 1 U2 2 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 OCT 19 PY 2005 VL 32 IS 20 AR L20803 DI 10.1029/2005GL024214 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 977UI UT WOS:000232828300007 ER PT J AU Song, YT Ji, C Fu, LL Zlotnicki, V Shum, CK Yi, YC Hjorleifsdottir, V AF Song, YT Ji, C Fu, LL Zlotnicki, V Shum, CK Yi, YC Hjorleifsdottir, V TI The 26 December 2004 tsunami source estimated from satellite radar altimetry and seismic waves SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID SUMATRA-ANDAMAN EARTHQUAKE; 1992 NICARAGUA EARTHQUAKE; 1979 IMPERIAL-VALLEY; GENERATION; CALIFORNIA; INVERSION; MOTION; ALASKA; FAULT AB The 26 December 2004 Indian Ocean tsunami was the first earthquake tsunami of its magnitude to occur since the advent of both digital seismometry and satellite radar altimetry. Both have independently recorded the event from different physical aspects. The seismic data has then been used to estimate the earthquake fault parameters, and a three-dimensional ocean-general-circulation-model (OGCM) coupled with the fault information has been used to simulate the satellite-observed tsunami waves. Here we show that these two datasets consistently provide the tsunami source using independent methodologies of seismic waveform inversion and ocean modeling. Cross-examining the two independent results confirms that the slip function is the most important condition controlling the tsunami strength, while the geometry and the rupture velocity of the tectonic plane determine the spatial patterns of the tsunami. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. CALTECH, Seismol Lab, Pasadena, CA 91125 USA. Ohio State Univ, Columbus, OH 43210 USA. RP Song, YT (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM song@pacific.jpl.nasa.gov OI hjorleifsdottir, vala/0000-0003-3275-108X NR 23 TC 28 Z9 28 U1 3 U2 7 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 OCT 18 PY 2005 VL 32 IS 20 AR L20601 DI 10.1029/2005GL023683 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 977UH UT WOS:000232828200003 ER PT J AU Connerney, JEP Acuna, MH Ness, NF Kletetschka, G Mitchell, DL Lin, RP Reme, H AF Connerney, JEP Acuna, MH Ness, NF Kletetschka, G Mitchell, DL Lin, RP Reme, H TI Tectonic implications of Mars crustal magnetism SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article DE magnetic; planetary; plate tectonics ID PLATE-TECTONICS; FIELD; ANOMALIES; EVOLUTION; PLUMES; MANTLE; FAULTS; OCEAN; FLOOR AB Mars currently has no global magnetic field of internal origin but must have had one in the past, when the crust acquired intense magnetization, presumably by cooling in the presence of an Earth-like magnetic field (thermoremanent magnetization). A new map of the magnetic field of Mars, compiled by using measurements acquired at an approximate to 400-km mapping altitude by the Mars Global Surveyor spacecraft, is presented here. The increased spatial resolution and sensitivity of this map provide new insight into the origin and evolution of the Mars crust. Variations in the crustal magnetic field appear in association with major faults, some previously identified in imagery and topography (Cerberus Rupes and Valles Marineris). Two parallel great faults are identified in Terra Meridiani by offset magnetic field contours. They appear similar to transform faults that occur in oceanic crust on Earth, and support the notion that the Mars crust formed during an early era of plate tectonics. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Delaware, Newark, DE 19716 USA. Univ Calif Berkeley, Berkeley, CA 94720 USA. Catholic Univ Amer, Washington, DC 20064 USA. Ctr Etud Spatiale Rayonnements, F-31028 Toulouse, France. RP Connerney, JEP (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM jack.connerney@nasa.gov; nfnudel@yahoo.com RI Kletetschka, Gunther/C-9996-2011; connerney, john/I-5127-2013 OI Kletetschka, Gunther/0000-0002-0645-9037; NR 35 TC 95 Z9 98 U1 1 U2 16 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD OCT 18 PY 2005 VL 102 IS 42 BP 14970 EP 14975 DI 10.1073/pnas.0507469102 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 977NZ UT WOS:000232811800008 PM 16217034 ER PT J AU Araujo-Pradere, EA Fuller-Rowell, TJ Codrescu, MV AF Araujo-Pradere, EA Fuller-Rowell, TJ Codrescu, MV TI Characteristics of the ionospheric variability as a function of season, latitude, local time, and geomagnetic activity SO RADIO SCIENCE LA English DT Article ID GENERAL-CIRCULATION MODEL; STORM; THERMOSPHERE; VALIDATION AB An ionospheric F-2 critical frequency database has been assembled to determine the variability of the F region as a function of local time, latitude, season, and geomagnetic activity. The database comprises observations from 75 ionosonde stations covering a range of geomagnetic latitude and includes 43 storm intervals. The database was previously used to develop the Storm-Time Empirical Ionospheric Correction Model (STORM). The mean and standard deviation have been evaluated by sorting the data by local time, season (five intervals centered on equinox, solstice, and intermediate intervals), latitude (four regions each 20 degrees wide in geomagnetic latitude), and up to eight levels of geomagnetic activity. The geomagnetic activity index was based on a weighted integral of the previous 33 hours of ap and is the same as that used by the STORM model. The database covers a full solar cycle, but insufficient information was available to sort by solar activity without compromising the estimates of variability on the other sorting parameters. About half the data were contained in the first level of geomagnetic activity, between 0 and 500 units of filtered ap corresponding to Kp <= 2, and half above that level. When local time dependence was included in the binning, sufficient data were available to sort into two levels of geomagnetic activity, quiet (Kp <= 2(+)) and disturbed (Kp > 3(-)). For all latitudes and levels of geomagnetic activity, the lowest variability was typically found in summer (10-15%), and the largest variability occurred in winter (15-40%), with equinox (10-30%) lying between the solstice extremes. The exception was low latitudes at equinox, which had surprising low variability (10%), possibly because of the weak interhemispheric flow at this time of year. At middle and low latitudes, the variability tended to increase with geomagnetic activity in winter and equinox but remained fairly constant in summer. At high latitudes, the surprising result was that in all seasons, and in winter in particular, the variability tended to decrease, probably because of the increased upwelling of neutral molecular species and stronger chemical control of the ionosphere. The data have also been used to build a table of estimated variability suitable for inclusion in the International Reference Ionosphere or any other climatological model. For periods where data were scarce or nonexistent, an estimated variability was provided on the basis of expectations of the consequences of physical processes. This was necessary to fill in the table of values in order to develop a module suitable for inclusion in the International Reference Ionosphere. C1 Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80305 USA. NOAA, Space Environm Ctr, Boulder, CO 80305 USA. NASA, Goddard Space Flight Ctr, Raytheon ITSS, Greenbelt, MD 20771 USA. RP Univ Colorado, Cooperat Inst Res Environm Sci, 325 Broadway R SEC, Boulder, CO 80305 USA. EM eduardo.araujo@noaa.gov NR 18 TC 20 Z9 20 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0048-6604 EI 1944-799X J9 RADIO SCI JI Radio Sci. PD OCT 18 PY 2005 VL 40 IS 5 AR RS5009 DI 10.1029/2004RS003179 PG 15 WC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications SC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications GA 978DF UT WOS:000232851800001 ER PT J AU Malkova, N Ning, CZ AF Malkova, N Ning, CZ TI Photonic crystal waveguides with acute bending angles SO APPLIED PHYSICS LETTERS LA English DT Article ID TRANSMISSION; PROPAGATION AB We propose and study photonic crystal waveguides with bending angles smaller than 90 degrees. The waveguide is formed by coupled defect cavities. To achieve a reflectionless transmission through an acute angle, we surround the defects in the bends with distorted cells having a prescribed symmetry. Detailed analysis and numerical simulation confirm that the transmission through the acute bend can be increased by two orders of magnitude to 100%. (C) 2005 American Institute of Physics. C1 NASA, Ctr Nanotechnol, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Malkova, N (reprint author), NASA, Ctr Nanotechnol, Ames Res Ctr, Moffett Field, CA 94035 USA. EM nmalkova@mail.arc.nasa.gov; cning@arc.nasa.gov RI Ning, C. Z./D-4699-2009 OI Ning, C. Z./0000-0003-4583-8889 NR 13 TC 5 Z9 6 U1 0 U2 6 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 OCT 17 PY 2005 VL 87 IS 16 AR 161113 DI 10.1063/1.2105994 PG 3 WC Physics, Applied SC Physics GA 973YG UT WOS:000232557900013 ER PT J AU Harding, DJ Carabajal, CC AF Harding, DJ Carabajal, CC TI ICESat waveform measurements of within-footprint topographic relief and vegetation vertical structure SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article AB The Ice, Cloud and land Elevation Satellite (ICESat) mission determines land surface vertical structure within laser footprints due to topographic relief and vegetation using received waveforms recorded by the Geoscience Laser Altimeter System (GLAS). In low-relief areas with tree cover the waveforms and derived elevation products provide useful biophysical parameters, including maximum canopy height, crown depth, the outer-canopy ruggedness, and a measure of canopy cover. For areas where within-footprint topographic relief is large compared to vegetation height, interpretation of the waveforms is complex. The contribution of canopy and ground to received waveforms is illustrated by comparing them with co-located waveforms computed using an instrument model applied to high resolution Digital Elevation Models (DEMs). The model includes representations of the transmit pulse's spatial and temporal distributions, and the receiver field-of-view sensitivity and temporal smoothing. This provides a means to validate GLAS waveforms, elevation products, and footprint geolocation. C1 NASA, Planetary Geodynam Lab, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NASA, NVI Inc, Space Geodesy Lab, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Harding, DJ (reprint author), NASA, Planetary Geodynam Lab, Goddard Space Flight Ctr, Code 698, Greenbelt, MD 20771 USA. EM david.j.harding@nasa.gov RI Harding, David/F-5913-2012 NR 9 TC 140 Z9 146 U1 2 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 OCT 15 PY 2005 VL 32 IS 21 AR L21S10 DI 10.1029/2005GL023471 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 975TU UT WOS:000232686400001 ER PT J AU Eisner, LB Cowles, TJ AF Eisner, LB Cowles, TJ TI Spatial variations in phytoplankton pigment ratios, optical properties, and environmental gradients in Oregon coast surface waters SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID CALIFORNIA CURRENT SYSTEM; PARTICLE-SIZE DISTRIBUTION; ABSORPTION-COEFFICIENTS; NORTHERN CALIFORNIA; UPWELLING JET; ALGAL BLOOMS; LIGHT; PHOTOACCLIMATION; ATTENUATION; IRRADIANCE AB In situ optics and hydrographic measurements, along with discrete samples for calibration, were used to assess spatial variations in phytoplankton characteristics and taxonomic composition (pigment ratios, relative particle size distribution, and chlorophyll a (chl a) concentration) in Oregon coast surface waters during August 2001. The relationships between environmental parameters (nutrients, light, temperature), photoprotective: photosynthetic carotenoid (PPC:PSC) ratios, and in situ spectral absorption and beam attenuation from ac-9 measurements were also evaluated. We computed a "slope'' index to evaluate changes in shapes of the phytoplankton absorption (a(ph)) spectra: a(ph) slope = (a(ph)488 - a(ph)532)/[a(ph)676 . (488-532 nm)]. Significant linear relationships were seen between PPC: PSC ratios and the aph slope parameter for surface samples grouped by location, date, and water mass characteristics. We observed high spatial variability in the phytoplankton photophysiological and taxonomic indicators derived from our optical measurements. Lower PPC: PSC ratios and larger particle size distributions were seen near the coast in colder upwelled water compared to locations farther offshore with warmer, more nutrient deplete water. Temperature and photosynthetic available radiation explained 42% of the variability in PPC:PSC ratios for all surface samples and 61% for surface samples with <2 mu M dissolved inorganic nitrogen. Temperature alone explained 87% of the variability in PPC:PSC ratios (estimated from ac-9 absorption data) and 72% of the variability in relative particle size distribution (estimated from ac-9 beam attenuation data) for Heceta Bank samples collected over 4 days, inshore and offshore of an upwelling front. C1 Oregon State Univ, Coll Ocean & Atmospher Sci, Corvallis, OR 97331 USA. RP Eisner, LB (reprint author), Natl Marine Fisheries Serv, Auke Bay Lab, Natl Ocean & Atmospher Adm, 11305 Glacier Highway, Juneau, AK 99801 USA. EM lisa.eisner@noaa.gov; tjc@coas.oregonstate.edu NR 45 TC 5 Z9 5 U1 1 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9275 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD OCT 15 PY 2005 VL 110 IS C10 AR C10S14 DI 10.1029/2004JC002614 PG 17 WC Oceanography SC Oceanography GA 975UK UT WOS:000232688400001 ER PT J AU Spedalieri, FM Lee, H Florescu, M Kapale, KT Yurtsever, U Dowling, JP AF Spedalieri, FM Lee, H Florescu, M Kapale, KT Yurtsever, U Dowling, JP TI Exploiting the Quantum Zeno effect to beat photon loss in linear optical quantum information processors SO OPTICS COMMUNICATIONS LA English DT Article DE quantum information; quantum computation; Quantum Zeno effect; QND measurement AB We devise a new technique to enhance transmission of quantum information through linear optical quantum information processors. The idea is based on applying the Quantum Zeno effect to the process of photon absorption. By frequently monitoring the presence of the photon through a quantum non-demolition (QND) measurement the absorption is suppressed. Quantum information is encoded in the polarization degrees of freedom and is therefore not affected by the measurement. Some implementations of the QND measurement are proposed. (c) 2005 Elsevier B.V. All rights reserved. C1 CALTECH, Jet Prop Lab, Quantum Comp Technol Grp, Pasadena, CA 91109 USA. Louisiana State Univ, Dept Phys & Astron, Baton Rouge, LA 70803 USA. RP Spedalieri, FM (reprint author), CALTECH, Jet Prop Lab, Quantum Comp Technol Grp, Mail Stop 126-347,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Federico.Spedalieri@jpl.nasa.gov RI Florescu, Marian/E-9009-2010; DOWLING, JONATHAN/L-2749-2013 NR 18 TC 8 Z9 8 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0030-4018 J9 OPT COMMUN JI Opt. Commun. PD OCT 15 PY 2005 VL 254 IS 4-6 BP 374 EP 379 DI 10.1016/j.optcom.2005.05.033 PG 6 WC Optics SC Optics GA 972PL UT WOS:000232465600022 ER PT J AU Amador, JJ AF Amador, JJ TI Sequential clustering by statistical methodology SO PATTERN RECOGNITION LETTERS LA English DT Article DE clustering; sequential algorithms; Gaussian distribution; hashing ID ALGORITHM AB To overcome the limitation of requiring the cluster threshold with the parametric approach, this paper presents a clustering constraint which first considers an estimate of the global distribution. The clustering process moves from local clusters identifying the data globally to larger clusters with a specified density function. Merging then occurs to provide a statistically supported representation of the data. A hashing-based sequential clustering algorithm is introduced which utilizes the initial and merging constraints. Experimental data shows the methods effectiveness at classifying varying cluster shapes and sizes when compared to recent clustering techniques. Published by Elsevier B.V. C1 NASA, John F Kennedy Space Ctr, Kennedy Space Ctr, FL 32899 USA. RP NASA, John F Kennedy Space Ctr, VA-El, Kennedy Space Ctr, FL 32899 USA. EM jose.j.amador@nasa.gov NR 24 TC 2 Z9 2 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-8655 EI 1872-7344 J9 PATTERN RECOGN LETT JI Pattern Recognit. Lett. PD OCT 15 PY 2005 VL 26 IS 14 BP 2152 EP 2163 DI 10.1016/j.patrec.2005.04.003 PG 12 WC Computer Science, Artificial Intelligence SC Computer Science GA 973MP UT WOS:000232527200003 ER PT J AU Burlaga, LF Vinas, AF AF Burlaga, LF Vinas, AF TI Triangle for the entropic index q of non-extensive statistical mechanics observed by Voyager 1 in the distant heliosphere SO PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS LA English DT Article DE nonlinear dynamics; nonextensive statistical mechanics; metastable states; mixing; weak chaos; q-triplet; heliospheric magnetic field ID AU AB Tsallis [Physica A 340 (2004) 1] identified a set of numbers, the "q-triplet" = {q(stat),q(sen),q(rel)} system described by nonextensive statistical mechanics. The deviation of the q's from unity is a measure of the departure from thermodynamic equilibrium. We present observations of the q-triplets derived from two sets of daily averages of the magnetic field strength B observed by Voyager 1 in the solar wind near 40 AU during 1989 and near 85 AU during 2002, respectively. The results for 1989 do not differ significantly from those for 2002. We find q(stat) = 1.75 +/- 0.06, q(sen), = -0.6 +/- 0.2, and q(rel) = 3.8 +/- 0.3. C1 NASA, Goddard Space Flight Ctr, Lab Solar & Space Phys, Greenbelt, MD 20771 USA. RP NASA, Goddard Space Flight Ctr, Lab Solar & Space Phys, Code 662-2, Greenbelt, MD 20771 USA. EM leonard.f.burlaga@nasa.gov NR 16 TC 67 Z9 67 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-4371 EI 1873-2119 J9 PHYSICA A JI Physica A PD OCT 15 PY 2005 VL 356 IS 2-4 BP 375 EP 384 DI 10.1016/j.physa.2005.06.065 PG 10 WC Physics, Multidisciplinary SC Physics GA 961QB UT WOS:000231675800007 ER PT J AU Drolet, GG Huemmrich, KF Hall, FG Middleton, EM Black, TA Barr, AG Margolis, HA AF Drolet, GG Huemmrich, KF Hall, FG Middleton, EM Black, TA Barr, AG Margolis, HA TI A MODIS-derived photochemical reflectance index to detect inter-annual variations in the photosynthetic light-use efficiency of a boreal deciduous forest SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE photochemical reflectance index; MODIS; light use efficiency; gross primary production; boreal deciduous forest; regional analysis ID LEAF-AREA INDEX; RADIATION-USE-EFFICIENCY; GROSS PRIMARY PRODUCTION; NET PRIMARY PRODUCTION; XANTHOPHYLL CYCLE; SATELLITE DATA; SHADE LEAVES; ASPEN FOREST; ECOSYSTEM; VEGETATION AB The relationships between ecosystem-level light use efficiency (LUE) obtained from an eddy covariance flux tower and MODIS-derived values of a scaled Photochemical Reflectance Index (sPRI) were investigated for a boreal aspen stand (Populus tremuloides Michx.) in Saskatchewan, Canada. Using MODIS ocean band 11 at 531 nm, we tried to detect variations in canopy reflectance related to the xanthophyll cycle. We tested several other MODIS bands as the reference band because the 570 nm reference band that had been determined to be optimum for calculating PRI in earlier studies is not available on MODIS. While LUE varied greatly within the 2001, 2002, and 2003 growing seasons, the Normalized Difference Vegetation Index (NDVI) calculated from tower sensors remained stable. LUE had a negative exponential relationship with vapor pressure deficit and air temperature, and was at a maximum when absorbed PAR was <200 mu mol m(-2) s(-1). The range and magnitude of tower-based LUE values were smaller on clear days, when MODIS acquisitions were possible, than they were overall. Furthermore, the orbital parameters of the Terra and Aqua satellites restricted MODIS acquisitions to a 2.5-h period in early afternoon at out study site when LUE values were typically lower than they were earlier in the day. Strong correlations between MODIS-sPRI and LUE were found only for backscatter reflectance scenes when band 13 (667 nm) was used as the reference band. The correlations were higher for sPRI calculated from top of atmosphere reflectances than for surface reflectances (r(2) = 0.76 and 0.53, respectively). The absolute backscatter reflectance of bands 11, 12 (551 nm), and 13 all decreased with increasing LUE. The decrease in band 13 suggests that the correlation between sPRI and LUE that we observed was caused by reductions in canopy chlorophyll content from 2001 to 2003 and/or by increased visibility of brighter non-photosynthetic material. Regional values of sPRI from 260 deciduous forest pixels in the 10,000 km(2) Vicinity of the tower for two contrasting days, one in 2001 and one in 2003, were consistent with that observed for the flux tower footprint. (C) 2005 Elsevier Inc. All rights reserved. C1 Univ Laval, Fac Foresterie & Geomat, Ste Foy, PQ G1K 7P4, Canada. NASA, Biospher Sci Branch, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Maryland Baltimore Cty, Joint Ctr Earth Syst Technol, Baltimore, MD 21228 USA. Univ British Columbia, Fac Agr Sci, Vancouver, BC V6T 1Z4, Canada. Meteorol Serv Canada, Climate Res Branch, Saskatoon, SK S7N 3H5, Canada. RP Margolis, HA (reprint author), Univ Laval, Fac Foresterie & Geomat, Pavillon Abitibi Price, Ste Foy, PQ G1K 7P4, Canada. EM Hank.Margolis@sbf.ulaval.ca RI Barr, Alan/H-9939-2014 NR 69 TC 119 Z9 124 U1 6 U2 34 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 OCT 15 PY 2005 VL 98 IS 2-3 BP 212 EP 224 DI 10.1016/j.rse.2005.07.006 PG 13 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 976OL UT WOS:000232742900005 ER PT J AU Carter, GA Knapp, AK Anderson, JE Hoch, GA Smith, MD AF Carter, GA Knapp, AK Anderson, JE Hoch, GA Smith, MD TI Indicators of plant species richness in AVIRIS spectra of a mesic grassland SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE AVIRIS; biodiversity; bison grazing; hyperspectral; grassland; plant species richness; radiance; reflectance; spatial variability; spectral mixing; soil exposure ID TALLGRASS PRAIRIE; ECOSYSTEM PROCESSES; BIOLOGICAL DIVERSITY; SATELLITE IMAGES; COVER TYPES; BIODIVERSITY; COMMUNITY; HABITAT; HETEROGENEITY; VEGETATION AB Hyperspectral imagery of the Konza Prairie Biological Station in northeastern Kansas was used to evaluate upwelling spectral radiance, prairie spectral reflectance and band ratios of each as potential indicators of vascular plant species richness in a mesic grassland. The extent to which spatial variability in these parameters related to plant species richness also was investigated. A 224 channel hyperspectral data cube acquired in June 2000 by the Airborne Visible and Infrared Imaging Spectrometer (AVIRIS) provided complete coverage of the 400-2500 nm range at approximately 10 run per channel. After band deletions accounted for detector overlap and strong atmospheric attenuation features, 176 bands were retained for analysis and spanned the 404-2400 nm range. Prairie reflectance was estimated via radiative transfer modeling and scaling to a library spectrum of highway construction material. Data were sampled from pixels having a 19 m ground sample distance (GSD) to represent each of 93 vegetation sampling transects. Reflectance and radiance at mid-infrared wavelengths (e.g., 1553 nm), and band ratios that were based on atmospheric windows in the red, near-infrared and mid-infrared spectra estimated species richness to within 6 to 7 species per transect. The 856 to 780 nm radiance or reflectance ratio yielded maximum adjusted coefficients of determination (r(2)) of approximately 0.4 in regressions with richness when data from bison-grazed and ungrazed areas were combined. These regressions remained significant (p <= 0.001) when only ungrazed areas were assessed although r(2) reduced to approximately 0.2. Richness was related significantly also to the 433 to 674 nm reflectance ratio for grazed-plus-ungrazed and ungrazed-only areas. In contrast, the effectiveness of the 433 to 674 nm radiance ratio was reduced by atmospheric backscatter. Species richness did not correlate strongly or consistently with transect spatial variability (coefficient of variation or range) in radiance, reflectance or band ratio value, apparently as a consequence of the relatively small area sampled for each transect (approximately 0.5 ha). Relationships between richness and prairie spectral features were explained by the influence of soil exposure on both parameters. Richness and estimated soil exposure tended to increase from ungrazed lowlands, to ungrazed slopes, to ungrazed uplands to grazed areas. Remotely sensed estimates of soil exposure may be particularly useful in addressing plant species richness on grazed grasslands owing to an overall similarity in spectral reflectance among dominant plant species. (C) 2005 Elsevier Inc. All rights reserved. C1 Univ So Mississippi, Gulf Coast Geospatial Ctr, Ocean Springs, MS 39564 USA. Univ So Mississippi, Dept Coastal Sci, Ocean Springs, MS 39564 USA. Colorado State Univ, Dept Biol, Ft Collins, CO 80523 USA. NASA, Appl Sci Directorate, Stennis Space Ctr, MS USA. Concordia Coll, Dept Biol, Moorhead, MN USA. Yale Univ, Dept Ecol & Evolutionary Biol, New Haven, CT USA. RP Carter, GA (reprint author), Univ So Mississippi, Gulf Coast Geospatial Ctr, POB 7000,703 E Beach Dr, Ocean Springs, MS 39564 USA. EM greg.carter@usm.edu RI Knapp, Alan/A-2931-2008; Smith, Melinda/J-8987-2014 NR 49 TC 20 Z9 21 U1 3 U2 19 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 OCT 15 PY 2005 VL 98 IS 2-3 BP 304 EP 316 DI 10.1016/j.rse.2005.08.001 PG 13 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 976OL UT WOS:000232742900011 ER PT J AU Vaughan, RG Hook, SJ Ramsey, MS Realmuto, VJ Schneider, DJ AF Vaughan, RG Hook, SJ Ramsey, MS Realmuto, VJ Schneider, DJ TI Monitoring eruptive activity at mount St. Helens with TIR image data SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID THERMAL EMISSION; VOLCANOS AB Thermal infrared (TIR) data from the MASTER airborne imaging spectrometer were acquired over Mount St. Helens in Sept and Oct, 2004, before and after the onset of recent eruptive activity. Pre-eruption data showed no measurable increase in surface temperatures before the first phreatic eruption on Oct 1. MASTER data acquired during the initial eruptive episode on Oct 14 showed maximum temperatures of similar to 330 degrees C and TIR data acquired concurrently from a Forward Looking Infrared (FLIR) camera showed maximum temperatures similar to 675 degrees C, in narrow (similar to 1-m) fractures of molten rock on a new resurgent dome. MASTER and FLIR thermal flux calculations indicated a radiative cooling rate of similar to 714 J/m(2)/s over the new dome, corresponding to a radiant power of similar to 24 MW. MASTER data indicated the new dome was dacitic in composition, and digital elevation data derived from LIDAR acquired concurrently with MASTER showed that the dome growth correlated with the areas of elevated temperatures. Low SO2 concentrations in the plume combined with sub-optimal viewing conditions prohibited quantitative measurement of plume SO2. The results demonstrate that airborne TIR data can provide information on the temperature of both the surface and plume and the composition of new lava during eruptive episodes. Given sufficient resources, the airborne instrumentation could be deployed rapidly to a newly-awakening volcano and provide a means for remote volcano monitoring. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Pittsburgh, Dept Geol & Planetary Sci, Pittsburgh, PA 15260 USA. US Geol Survey, Alaska Volcano Observ, Anchorage, AK 99508 USA. RP Vaughan, RG (reprint author), CALTECH, Jet Prop Lab, MS 183-501,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM greg.vaughan@jpl.nasa.gov; simon.j.hook@jpl.nasa.gov; ramsey@ivis.eps.pitt.edu; vincent.j.realmuto@jpl.nasa.gov; djschneider@usgs.gov RI Ramsey, Michael/D-9183-2013 NR 10 TC 20 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 OCT 14 PY 2005 VL 32 IS 19 AR L19305 DI 10.1029/2005GL024112 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 975TR UT WOS:000232686000003 ER PT J AU Gopalswamy, N Aguilar-Rodriguez, E Yashiro, S Nunes, S Kaiser, ML Howard, RA AF Gopalswamy, N Aguilar-Rodriguez, E Yashiro, S Nunes, S Kaiser, ML Howard, RA TI Type II radio bursts and energetic solar eruptions SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID CORONAL MASS EJECTIONS; PARTICLE EVENTS; INTERPLANETARY SHOCKS; WIND SPACECRAFT; EMISSIONS; ORIGIN; SUN; ACCELERATION; PROPAGATION; CMES AB [1] We report on a study of type II radio bursts from the Wind/WAVES experiment in conjunction with white-light coronal mass ejections (CME) from the Solar and Heliospheric Observatory (SOHO). The type II bursts considered here have emission components in all the spectral domains: metric, decameter-hectometric (DH) and kilometric ( km), so we refer to them as m-to-km type II bursts. CMEs associated with the m-to-km type II bursts were more energetic than those associated with bursts in any single wavelength regime. CMEs associated with type II bursts confined to the metric domain were more energetic ( wider and faster) than the general population of CMEs but less energetic than CMEs associated with DH type II bursts. Thus the CME kinetic energy seems to organize the life time of the type II bursts. Contrary to previous results, the starting frequency of metric type II bursts with interplanetary counterparts seems to be no different from that of type II bursts without interplanetary counterparts. We also verified this by showing that the average CME height at the onset time of the type II bursts is the same for the two metric populations. The majority (78%) of the m-to-km type II bursts were associated with solar energetic particle (SEP) events. The solar sources of the small fraction of m- to-km type II bursts without SEP association were poorly connected to the observer near Earth. Finally, we found that the m- to-km type II bursts were associated with bigger flares compared to the purely metric type II bursts. C1 NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Greenbelt, MD 20771 USA. Catholic Univ Amer, Washington, DC 20064 USA. Univ Nacl Autonoma Mexico, Inst Geofis, Mexico City 04510, DF, Mexico. USN, Res Lab, Washington, DC 20375 USA. RP Gopalswamy, N (reprint author), NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Code 695-0,Bldg 21,Room 260, Greenbelt, MD 20771 USA. EM gopals@fugee.gsfc.nasa.gov RI Gopalswamy, Nat/D-3659-2012 NR 40 TC 57 Z9 57 U1 0 U2 0 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 OCT 14 PY 2005 VL 110 IS A12 AR A12S07 DI 10.1029/2005JA011158 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 975UU UT WOS:000232689700002 ER PT J AU Yashiro, S Gopalswamy, N Akiyama, S Michalek, G Howard, RA AF Yashiro, S Gopalswamy, N Akiyama, S Michalek, G Howard, RA TI Visibility of coronal mass ejections as a function of flare location and intensity SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID SMM OBSERVATIONS; SOLAR-FLARES; SHOCK-WAVES; TRANSIENTS; EMISSION; EVENTS; SPEEDS; STORMS; LASCO; CMES AB [1] We report the visibility ( detection efficiency) of coronal mass ejections (CMEs) of the Large Angle Spectrometric Coronagraph (LASCO) on board the Solar and Heliospheric Observatory (SOHO). We collected 1301 X-ray flare events ( above C3 level) detected by the GOES satellite and examined their CME associations using data from LASCO coronagraphs. The CME visibility was examined using the longitudinal variation of CME association of X-ray flares, under the assumption that all CMEs associated with limb flares are detectable by LASCO. Our findings are ( 1) the CME association rate clearly increased with X-ray flare size from 20% for C-class flares ( between C3 and C9 levels) to 100% for huge flares ( above X3 level), ( 2) all CMEs associated with X-class flares were detected by the LASCO coronagraphs, while half ( 25 - 67%) of CMEs associated with C-class flares were invisible. We examined the statistical properties of the flare-associated CMEs and compared them by flare size and longitude. CMEs associated with X-class flares were significantly faster ( median 1556 km/s) and wider ( median 244 degrees) than those of CMEs associated with disk C-class flares ( 432 km/s, 68 degrees). We conclude that all fast and wide CMEs are detectable by LASCO, but slow and narrow CMEs may not be visible when the CMEs originate from the disk center. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Jagiellonian Univ, Astron Observ, PL-30244 Krakow, Poland. USN, Res Lab, Washington, DC 20375 USA. RP Catholic Univ Amer, Washington, DC 20064 USA. EM yashiro@cdaw.gsfc.nasa.gov; michalek@oa.uj.edu.pl; russ.howard@nrl.navy.mil RI Gopalswamy, Nat/D-3659-2012 NR 39 TC 38 Z9 38 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 OCT 14 PY 2005 VL 110 IS A12 AR A12S05 DI 10.1029/2005JA011151 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 975UU UT WOS:000232689700001 ER PT J AU Lukomski, M MacAskill, JA Seccombe, DP McGrath, C Sutton, S Teeuwen, J Kedzierski, W Reddish, TJ McConkey, JW van Wijngaarden, WA AF Lukomski, M MacAskill, JA Seccombe, DP McGrath, C Sutton, S Teeuwen, J Kedzierski, W Reddish, TJ McConkey, JW van Wijngaarden, WA TI New measurements of absolute total cross sections for electron impact on caesium using a magneto-optical trap SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Article ID ATOMS; SCATTERING AB A new magneto-optical trap designed specifically for the measurement of absolute electron impact cross sections is described. Experimental results for electron impact total cross sections involving 6(2)S ground state Cs are presented over the energy range 5-200 eV. Significant disagreement is obtained between our experimental data and convergent close coupling (CCC) or Breit-Pauli R-matrix calculations at the lower energies. Above 100 eV our data overlap earlier measurements from this laboratory made with a completely different apparatus and agree well with the CCC results. A comparison is made with other measurements using more conventional techniques. C1 Univ Windsor, Dept Phys, Windsor, ON N9B 3P4, Canada. Jagiellonian Univ, Inst Fizyki, PL-30059 Krakow, Poland. CALTECH, Jet Propuls Lab, Pasadena, CA 91109 USA. Royal Victoria Hosp, No Ireland Reg Med Phys Agcy, Belfast BT12 6BA, Antrim, North Ireland. York Univ, Dept Phys, N York, ON M3J 1P3, Canada. RP Lukomski, M (reprint author), Univ Windsor, Dept Phys, Windsor, ON N9B 3P4, Canada. OI Lukomski, Michal/0000-0001-7942-9026 NR 23 TC 4 Z9 4 U1 6 U2 12 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-4075 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD OCT 14 PY 2005 VL 38 IS 19 BP 3535 EP 3545 DI 10.1088/0953-4075/38/19/006 PG 11 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 991KJ UT WOS:000233812600009 ER PT J AU A'Hearn, MF Belton, MJS Delamere, WA Kissel, J Klaasen, KP McFadden, LA Meech, KJ Melosh, HJ Schultz, PH Sunshine, JM Thomas, PC Veverka, J Yeomans, DK Baca, MW Busko, I Crockett, CJ Collins, SM Desnoyer, M Eberhardy, CA Ernst, CM Farnham, TL Feaga, L Groussin, O Hampton, D Ipatov, SI Li, JY Lindler, D Lisse, CM Mastrodemos, N Owen, WM Richardson, JE Wellnitz, DD White, RL AF A'Hearn, MF Belton, MJS Delamere, WA Kissel, J Klaasen, KP McFadden, LA Meech, KJ Melosh, HJ Schultz, PH Sunshine, JM Thomas, PC Veverka, J Yeomans, DK Baca, MW Busko, I Crockett, CJ Collins, SM Desnoyer, M Eberhardy, CA Ernst, CM Farnham, TL Feaga, L Groussin, O Hampton, D Ipatov, SI Li, JY Lindler, D Lisse, CM Mastrodemos, N Owen, WM Richardson, JE Wellnitz, DD White, RL TI Deep Impact: Excavating comet Tempel 1 SO SCIENCE LA English DT Article ID P/WILD 2; NUCLEUS; MISSION; SURFACE; CHIRON AB Deep Impact collided with comet Tempel 1, excavating a crater controlled by gravity. The comet's outer layer is composed of 1- to 100-micrometer fine particles with negligible strength (<65 pascals). Local gravitational field and average nucleus density (600 kilograms per cubic meter) are estimated from ejecta fallback. Initial ejecta were hot (>1000 kelvins). A large increase in organic material occurred during and after the event, with smaller changes in carbon dioxide relative to water. On approach, the spacecraft observed frequent natural outbursts, a mean radius of 3.0 +/- 0.1 kilometers, smooth and rough terrain, scarps, and impact craters. A thermal map indicates a surface in equilibrium with sunlight. C1 Univ Maryland, College Pk, MD 20742 USA. Belton Space Explorat Initiat, Tucson, AZ 85716 USA. Delamere Support Serv, Boulder, CO 80301 USA. Max Planck Inst Solar Syst Res, D-37191 Katlenburg Lindau, Germany. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Hawaii, Honolulu, HI 96822 USA. Univ Arizona, Tucson, AZ 85721 USA. Brown Univ, Providence, RI USA. SAIC, Chantilly, VA 20151 USA. Cornell Univ, Ithaca, NY 14853 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Ball Aerosp & Technol Corp, Boulder, CO 80301 USA. Sigma Sci, Greenbelt, MD 20771 USA. Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. RP A'Hearn, MF (reprint author), Univ Maryland, College Pk, MD 20742 USA. EM ma@astro.umd.edu RI White, Richard/A-8143-2012; Wellnitz, Dennis/B-4080-2012; Ernst, Carolyn/I-4902-2012; McFadden, Lucy-Ann/I-4902-2013; Lisse, Carey/B-7772-2016; Ipatov, Sergei/O-2302-2014 OI McFadden, Lucy-Ann/0000-0002-0537-9975; Lisse, Carey/0000-0002-9548-1526; Ipatov, Sergei/0000-0002-1413-9180 NR 23 TC 425 Z9 428 U1 0 U2 27 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 OCT 14 PY 2005 VL 310 IS 5746 BP 258 EP 264 DI 10.1126/science.1118923 PG 7 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 975NV UT WOS:000232670100037 PM 16150978 ER PT J AU Meech, KJ Ageorges, N A'Hearn, MF Arpigny, C Ates, A Aycock, J Bagnulo, S Bailey, J Barber, R Barrera, L Barrena, R Bauer, JM Belton, MJS Bensch, F Bhattacharya, B Biver, N Blake, G Bocklee-Morvan, D Boehnhardt, H Bonev, BP Bonev, T Buie, MW Burton, MG Butner, HM Cabanac, R Campbell, R Campins, H Capria, MT Carroll, T Chaffee, F Charnley, SB Cleis, R Coates, A Cochran, A Colom, P Conrad, A Coulson, IM Crovisier, J deBuizer, J Dekany, R de Leon, J Dello Russo, N Delsanti, A DiSanti, M Drummond, J Dundon, L Etzel, PB Farnham, TL Feldman, P Fernandez, YR Filipovic, MD Fisher, S Fitzsimmons, A Fong, D Fugate, R Fujiwara, H Fujiyoshi, T Furusho, R Fuse, T Gibb, E Groussin, O Gulkis, S Gurwell, M Hadamcik, H Hainaut, O Harker, D Harrington, D Harwit, M Hasegawa, S Hergenrother, CW Hirst, P Hodapp, K Honda, M Howell, ES Hutsemekers, D Iono, D Ip, WH Jackson, W Jehin, E Jiang, ZJ Jones, GH Jones, PA Kadono, T Kamath, UW Kaufl, HU Kasuga, T Kawakita, H Kelley, MS Kerber, F Kidger, M Kinoshita, D Knight, M Lara, L Larson, SM Lederer, S Lee, CF Levasseur-Regourd, AC Li, JY Li, QS Licandro, J Lin, ZY Lisse, CM LoCurto, G Lovell, AJ Lowry, SC Lyke, J Lynch, D Ma, J Magee-Sauer, K Maheswar, G Manfroid, J Marco, O Martin, P Melnick, G Miller, S Miyata, T Moriarty-Schieven, GH Moskovitz, N Mueller, BEA Mumma, MJ Muneer, S Neufeld, DA Ootsubo, T Osip, D Pandea, SK Pantin, E Paterno-Mahler, R Patten, B Penprase, BE Peck, A Petitas, G Pinilla-Alonso, N Pittichova, J Pompei, E Prabhu, TP Qi, C Rao, R Rauer, H Reitsema, H Rodgers, SD Rodriguez, P Ruane, R Ruch, G Rujopakarn, W Sahu, DK Sako, S Sakon, I Samarasinha, N Sarkissian, JM Saviane, I Schirmer, M Schultz, P Schulz, R Seitzer, P Sekiguchi, T Selman, F Serra-Ricart, M Sharp, R Snell, RL Snodgrass, C Stallard, T Stecklein, G Sterken, C Stuwe, JA Sugita, S Sumner, M Suntzeff, N Swaters, R Takakuwa, S Takata, N Thomas-Osip, J Thompson, E Tokunaga, AT Tozzi, GP Tran, H Troy, M Trujillo, C Van Cleve, J Vasundhara, R Vazquez, R Vilas, F Villanueva, G von Braun, K Vora, P Wainscoat, RJ Walsh, K Watanabe, J Weaver, HA Weaver, W Weiler, M Weissman, PR Welsh, WF Wilner, D Wolk, S Womack, M Wooden, D Woodney, LM Woodward, C Wu, ZY Wu, JH Yamashita, T Yang, B Yang, YB Yokogawa, S Zook, AC Zauderer, A Zhao, X Zhou, X Zucconi, JM AF Meech, KJ Ageorges, N A'Hearn, MF Arpigny, C Ates, A Aycock, J Bagnulo, S Bailey, J Barber, R Barrera, L Barrena, R Bauer, JM Belton, MJS Bensch, F Bhattacharya, B Biver, N Blake, G Bocklee-Morvan, D Boehnhardt, H Bonev, BP Bonev, T Buie, MW Burton, MG Butner, HM Cabanac, R Campbell, R Campins, H Capria, MT Carroll, T Chaffee, F Charnley, SB Cleis, R Coates, A Cochran, A Colom, P Conrad, A Coulson, IM Crovisier, J deBuizer, J Dekany, R de Leon, J Dello Russo, N Delsanti, A DiSanti, M Drummond, J Dundon, L Etzel, PB Farnham, TL Feldman, P Fernandez, YR Filipovic, MD Fisher, S Fitzsimmons, A Fong, D Fugate, R Fujiwara, H Fujiyoshi, T Furusho, R Fuse, T Gibb, E Groussin, O Gulkis, S Gurwell, M Hadamcik, H Hainaut, O Harker, D Harrington, D Harwit, M Hasegawa, S Hergenrother, CW Hirst, P Hodapp, K Honda, M Howell, ES Hutsemekers, D Iono, D Ip, WH Jackson, W Jehin, E Jiang, ZJ Jones, GH Jones, PA Kadono, T Kamath, UW Kaufl, HU Kasuga, T Kawakita, H Kelley, MS Kerber, F Kidger, M Kinoshita, D Knight, M Lara, L Larson, SM Lederer, S Lee, CF Levasseur-Regourd, AC Li, JY Li, QS Licandro, J Lin, ZY Lisse, CM LoCurto, G Lovell, AJ Lowry, SC Lyke, J Lynch, D Ma, J Magee-Sauer, K Maheswar, G Manfroid, J Marco, O Martin, P Melnick, G Miller, S Miyata, T Moriarty-Schieven, GH Moskovitz, N Mueller, BEA Mumma, MJ Muneer, S Neufeld, DA Ootsubo, T Osip, D Pandea, SK Pantin, E Paterno-Mahler, R Patten, B Penprase, BE Peck, A Petitas, G Pinilla-Alonso, N Pittichova, J Pompei, E Prabhu, TP Qi, C Rao, R Rauer, H Reitsema, H Rodgers, SD Rodriguez, P Ruane, R Ruch, G Rujopakarn, W Sahu, DK Sako, S Sakon, I Samarasinha, N Sarkissian, JM Saviane, I Schirmer, M Schultz, P Schulz, R Seitzer, P Sekiguchi, T Selman, F Serra-Ricart, M Sharp, R Snell, RL Snodgrass, C Stallard, T Stecklein, G Sterken, C Stuwe, JA Sugita, S Sumner, M Suntzeff, N Swaters, R Takakuwa, S Takata, N Thomas-Osip, J Thompson, E Tokunaga, AT Tozzi, GP Tran, H Troy, M Trujillo, C Van Cleve, J Vasundhara, R Vazquez, R Vilas, F Villanueva, G von Braun, K Vora, P Wainscoat, RJ Walsh, K Watanabe, J Weaver, HA Weaver, W Weiler, M Weissman, PR Welsh, WF Wilner, D Wolk, S Womack, M Wooden, D Woodney, LM Woodward, C Wu, ZY Wu, JH Yamashita, T Yang, B Yang, YB Yokogawa, S Zook, AC Zauderer, A Zhao, X Zhou, X Zucconi, JM TI Deep Impact: Observations from a worldwide Earth-based campaign SO SCIENCE LA English DT Article ID COMET-9P/TEMPEL-1; 9P/TEMPEL-1 AB On 4 July 2005, many observatories around the world and in space observed the collision of Deep Impact with comet 9P/Tempet 1 or its aftermath. This was an unprecedented coordinated observational campaign. These data show that (i) there was new material after impact that was compositionally different from that seen before impact; (ii) the ratio of dust mass to gas mass in the ejecta was much larger than before impact; (iii) the new activity did not last more than a few days, and by 9 July the comet's behavior was indistinguishable from its pre-impact behavior; and (iv) there were interesting transient phenomena that may be correlated with cratering physics. C1 Univ Hawaii Manoa, Inst Astron, Honolulu, HI 96822 USA. European So Observ, Santiago 19, Chile. Univ Maryland, College Pk, MD 20742 USA. Univ Liege, B-4000 Liege, Belgium. Pomona Coll, Claremont, CA 91711 USA. Keck Observ, Kamuela, HI 96743 USA. Macquarie Univ, Australian Ctr Astrobiol, Sydney, NSW 2109, Australia. UCL, London WC1E 6BT, England. Univ Metropolitana Ciencias Educ, Santiago, Chile. Inst Astrofis Canarias, E-38200 San Cristobal la Laguna, Tenerife, Spain. NASA, Jet Prop Lab, Pasadena, CA 91109 USA. Belton Space Initiat, Tucson, AZ 85716 USA. Univ Bonn, Inst Radioastron, D-53121 Bonn, Germany. CALTECH, Pasadena, CA 91125 USA. Observ Paris, F-92195 Meudon, France. Max Planck Sonnensyst Forsch, D-37191 Katlenburg Lindau, Germany. Univ Toledo, Toledo, OH 43606 USA. Inst Astron, Sofia 1784, Bulgaria. Lowell Observ, Flagstaff, AZ 86001 USA. Univ New S Wales, Sydney, NSW 2052, Australia. Joint Astron Ctr, Hilo, HI 96720 USA. Canada France Hawaii Telescope Corp, Kamuela, HI 96743 USA. Univ Cent Florida, Orlando, FL 32816 USA. Inst Astrofis Spaziale & Fis Cosm, I-00133 Rome, Italy. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. USAF, Res Lab, Kirtland AFB, NM 87117 USA. UCL, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England. Univ Texas, Austin, TX 78712 USA. Gemini Observ, Serena, Chile. Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20770 USA. San Diego State Univ, San Diego, CA 92182 USA. Johns Hopkins Univ, Baltimore, MD 21218 USA. Univ Western Sydney, Sydney, NSW 1797, Australia. Gemini Observ N, Hilo, HI 96720 USA. Queens Univ Belfast, Belfast BT7 1NN, Antrim, North Ireland. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Tokyo, Tokyo 1138654, Japan. Subaru Telescope, Hilo, HI 96720 USA. Waseda Univ, Tokyo 1698050, Japan. Univ Notre Dame, Notre Dame, IN 46556 USA. CNRS, Serv Aeron, F-91371 Verrieres Le Buisson, France. Univ Calif San Diego, La Jolla, CA 92093 USA. Cornell Univ, Ithaca, NY 14853 USA. Inst Space & Astronaut Sci, Kanagawa 2298510, Japan. Univ Arizona, Tucson, AZ 85721 USA. Arecibo Observ, Arecibo, PR 00612 USA. Natl Cent Univ, Tao Yuan 32001, Taiwan. Univ Calif Davis, Davis, CA 95616 USA. Natl Astron Observ, Beijing 100012, Peoples R China. Australian Telescope, Natl Facil, Epping, NSW 1710, Australia. Japan Agcy Marine Earth Sci & Technol, Kanagawa 2370061, Japan. Indian Inst Astrophys, Bangalore 560034, Karnataka, India. Natl Astron Observ Japan, Tokyo 1818588, Japan. Kyoto Sangyo Univ, Kyoto 6038555, Japan. Univ Minnesota, Minneapolis, MN 55455 USA. CSIC, Inst Astrofis Andalucia, E-18080 Granada, Spain. Calif State Univ San Bernardino, San Bernardino, CA 92407 USA. Isaac Newton Grp Telescopes, E-38700 La Palma, Spain. Agnes Scott Coll, Decatur, GA 30030 USA. Aerosp Corp, Los Angeles, CA 90009 USA. Rowan Univ, Glassboro, NJ 08028 USA. Natl Opt Astron Observ, Tucson, AZ 85719 USA. Nagoya Univ, Nagoya, Aichi 4648601, Japan. Las Campanas Observ, Pasadena, CA 91101 USA. CEA, Serv Astron, F-91191 Gif Sur Yvette, France. Fdn Galileo Galilei & Telescopio Nazl Galileo, La Palma 38700, Spain. Deutsch Zentrum Luft & Raumfahrt, D-12489 Berlin, Germany. Ball Aerosp, Boulder, CO 80306 USA. European Space Agcy, Madrid 28080, Spain. Univ Michigan, Ann Arbor, MI 48109 USA. Brown Univ, Providence, RI 02912 USA. European Space Agcy, NL-2200 AG Noordwijk, Netherlands. Anglo Australian Observ, Epping, NSW 1710, Australia. Univ Massachusetts, Amherst, MA 01003 USA. Univ Brussels, B-1050 Brussels, Belgium. Leiden Observ, NL-2300 RA Leiden, Netherlands. Osserv Astrofis Arcetri, I-50125 Florence, Italy. Univ Nacl Autonoma Mexico, Ensenada 22800, Baja California, Mexico. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Carnegie Inst Sci, Washington, DC 20015 USA. Coll William & Mary, Williamsburg, VA 23187 USA. St Cloud State Univ, St Cloud, MN 56301 USA. Observ Besancon, F-25010 Besancon, France. RP Meech, KJ (reprint author), Univ Hawaii Manoa, Inst Astron, 2680 Woodlawn Dr, Honolulu, HI 96822 USA. EM meech@ifa.hawaii.edu RI Pinilla-Alonso, Noemi/B-8583-2008; Charnley, Steven/C-9538-2012; Lisse, Carey/B-7772-2016; Vazquez, Roberto/L-3613-2016; Rujopakarn, Wiphu/E-7849-2012; Coates, Andrew/C-2396-2008; mumma, michael/I-2764-2013; Jones, Geraint/C-1682-2008; de Leon, Julia/H-7569-2015; Magee-Sauer, Karen/K-6061-2015; Dello Russo, Neil/G-2727-2015; Weaver, Harold/D-9188-2016 OI Snodgrass, Colin/0000-0001-9328-2905; Jones, Geraint/0000-0002-5859-1136; Lisse, Carey/0000-0002-9548-1526; Vazquez, Roberto/0000-0002-3279-9764; Coates, Andrew/0000-0002-6185-3125; de Leon, Julia/0000-0002-0696-0411; Magee-Sauer, Karen/0000-0002-4979-9875; Dello Russo, Neil/0000-0002-8379-7304; NR 15 TC 130 Z9 131 U1 2 U2 32 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 OCT 14 PY 2005 VL 310 IS 5746 BP 265 EP 269 DI 10.1126/science.1118978 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 975NV UT WOS:000232670100038 PM 16150977 ER PT J AU Mumma, MJ DiSanti, MA Magee-Sauer, K Bonev, BP Villanueva, GL Kawakita, H Dello Russo, N Gibb, EL Blake, GA Lyke, JE Campbell, RD Aycock, J Conrad, A Hill, GM AF Mumma, MJ DiSanti, MA Magee-Sauer, K Bonev, BP Villanueva, GL Kawakita, H Dello Russo, N Gibb, EL Blake, GA Lyke, JE Campbell, RD Aycock, J Conrad, A Hill, GM TI Parent volatiles in comet 9P/Tempel 1: Before and after impact SO SCIENCE LA English DT Article AB We quantified eight parent votatiles (H(2)O, C(2)H(6), HCN, CO, CH(3)OH, H(2)CO, C(2)H(2), and CH(4)) in the Jupiter-family comet Tempel 1 using high-dispersion infrared spectroscopy in the wavelength range 2.8 to 5.0 micrometers. The abundance ratio for ethane was significantly higher after impact, whereas those for methanol and hydrogen cyanide were unchanged. The abundance ratios in the ejecta are similar to those for most Oort cloud comets, but methanol and acetylene are tower in Tempel 1 by a factor of about 2. These results suggest that the volatile ices in Tempel 1 and in most Oort cloud comets originated in a common region of the protoplanetary disk. C1 NASA, Goddard Space Flight Ctr, Solar Syst Explorat Div, Greenbelt, MD 20771 USA. Rowan Univ, Dept Phys & Astron, Glassboro, NJ 08028 USA. Univ Toledo, Dept Phys & Astron, Ritter Astrophys Res Ctr, Toledo, OH 43606 USA. Kyoto Sangyo Univ, Dept Phys, Kita Ku, Kyoto 6038555, Japan. Johns Hopkins Univ, Appl Phys Lab, Space Dept, Planetary Explorat Grp, Laurel, MD 20723 USA. Univ Missouri, Dept Phys & Astron, St Louis, MO 63121 USA. CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA. WM Keck Observ, Kamuela, HI 96743 USA. RP Mumma, MJ (reprint author), NASA, Goddard Space Flight Ctr, Solar Syst Explorat Div, Greenbelt, MD 20771 USA. EM michael.j.mumma@nasa.gov RI mumma, michael/I-2764-2013; Magee-Sauer, Karen/K-6061-2015; Dello Russo, Neil/G-2727-2015 OI Magee-Sauer, Karen/0000-0002-4979-9875; Dello Russo, Neil/0000-0002-8379-7304 NR 19 TC 127 Z9 130 U1 1 U2 10 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 OCT 14 PY 2005 VL 310 IS 5746 BP 270 EP 274 DI 10.1126/science.1119337 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 975NV UT WOS:000232670100039 PM 16166477 ER PT J AU Sugita, S Ootsubo, T Kadono, T Honda, M Sako, S Miyata, T Sakon, I Yamashita, T Kawakita, H Fujiwara, H Fujiyoshi, T Takato, N Fuse, T Watanabe, J Furusho, R Hasegawa, S Kasuga, T Sekiguchi, T Kinoshita, D Meech, KJ Wooden, DH Ip, WH A'Hearn, MF AF Sugita, S Ootsubo, T Kadono, T Honda, M Sako, S Miyata, T Sakon, I Yamashita, T Kawakita, H Fujiwara, H Fujiyoshi, T Takato, N Fuse, T Watanabe, J Furusho, R Hasegawa, S Kasuga, T Sekiguchi, T Kinoshita, D Meech, KJ Wooden, DH Ip, WH A'Hearn, MF TI Subaru telescope observations of Deep Impact SO SCIENCE LA English DT Article ID VELOCITY DISTRIBUTIONS AB The impact cratering process on a comet is controversial but holds the key for interpreting observations of the Deep Impact collision with comet 9P/Tempel 1. Midinfrared data from the Cooled Mid-Infrared Camera and Spectrometer (COMICS) of the Subaru Telescope indicate that the large-scale dust plume ejected by the impact contained a large mass (similar to 10(6) kilograms) of dust and formed two wings approximately +/- 45 degrees from the symmetric center, both consistent with gravity as the primary control on the impact and its immediate aftermath. The dust distribution in the inner part of the plume, however, is inconsistent with a pure gravity control and implies that evaporation and expansion of volatiles accelerated dust. C1 Univ Tokyo, Dept Complex Sci & Engn, Chiba, Japan. Univ Tokyo, Inst Astron, Tokyo 113, Japan. Univ Tokyo, Dept Astron, Tokyo 113, Japan. Japan Aerosp Explorat Agcy, Inst Space & Astronaut Sci, Kanagawa, Japan. Brown Univ, Dept Geol Sci, Providence, RI 02912 USA. Nagoya Univ, Div Particle & Astrophys Sci, Aichi, Japan. Japan Agcy Marine Earth Sci & Technol, Inst Res Earth Evolut, Kanagawa, Japan. Natl Astron Observ Japan, Natl Inst Nat Sci, Subaru Telescope, Hilo, HI USA. Kyoto Sangyo Univ, Dept Phys, Kamigamo, Kyodo, Japan. Natl Astron Observ Japan, Tokyo, Japan. Waseda Univ, Tokyo, Japan. Natl Cent Univ, Inst Astron, Chungli 32054, Taiwan. Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA. NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. Univ Maryland, Dept Astron, College Pk, MD 20742 USA. RP Sugita, S (reprint author), Univ Tokyo, Dept Complex Sci & Engn, Chiba, Japan. EM sugita@k.u-tokyo.ac.jp NR 21 TC 74 Z9 74 U1 0 U2 11 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 OCT 14 PY 2005 VL 310 IS 5746 BP 274 EP 278 DI 10.1126/science.1119091 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 975NV UT WOS:000232670100040 PM 16166476 ER PT J AU Harker, DE Woodward, CE Wooden, DH AF Harker, DE Woodward, CE Wooden, DH TI The dust grains from 9P/Tempel 1 before and after the encounter with deep impact SO SCIENCE LA English DT Article ID KUIPER-BELT; INFRARED OBSERVATIONS; HALE-BOPP; COMETS; SPECTRA; SILICATE AB Gemini-N observed the properties of dust ejected from the nucleus of comet 9P/Tempel 1 before and after its encounter with Deep Impact. Marked changes were seen in the 7.8- to 13-micrometer spectral energy distribution and derived grain properties of the inner coma. A strong, broad silicate feature dominated by emission from amorphous pyroxene, amorphous olivine, and magnesium-rich crystalline olivine had developed by 1 hour after impact. The ejected dust mass is congruent to 10(4) to 10(6) kilograms on the basis of our models. Twenty-six hours later the silicate feature had faded, leaving a smooth featureless spectrum, similar to that observed before the impact, suggesting that the impact did not produce a new active region releasing small particles on the nucleus. C1 Univ Calif San Diego, Ctr Astrophys & Space Sci, La Jolla, CA 92093 USA. Univ Minnesota, Dept Astron, Minneapolis, MN 55455 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Harker, DE (reprint author), Univ Calif San Diego, Ctr Astrophys & Space Sci, 9500 Gilman Dr,Dept 0424, La Jolla, CA 92093 USA. EM dharker@ucsd.edu OI Harker, David/0000-0001-6397-9082 NR 26 TC 84 Z9 84 U1 0 U2 5 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 OCT 14 PY 2005 VL 310 IS 5746 BP 278 EP 280 DI 10.1126/science.1119143 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 975NV UT WOS:000232670100041 PM 16166478 ER PT J AU Xin, X Yan, F Koeth, TW Joseph, C Hu, J Wu, J Zhao, JH AF Xin, X Yan, F Koeth, TW Joseph, C Hu, J Wu, J Zhao, JH TI Demonstration of 4H-SiC visible-blind EUV and UV detector with large detection area SO ELECTRONICS LETTERS LA English DT Article AB 4H-SiC visible-blind photodetectors specially designed for extreme ultraviolet (EUV) as well as ultraviolet (UV) detection are fabricated and characterised. Spectral quantum efficiency (QE) from 21.5 to 400 not is determined. The devices have a 2 x 2 mm active area and less than I pA leakage current at low bias. The peak QE is 40-45% around 270 nm. Between 120-200 nm, the detector QE is about 4-20%. EUV light generates multiple electron hole pairs in the range of 21.5 to 77.5 nm, resulting in an apparent QE above 140% at 21.5 rind. C1 Rutgers State Univ, SiCLAB, Dept Elect & Comp Engn, Piscataway, NJ 08854 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Dept Phys & Astron, Piscataway, NJ 08854 USA. RP Xin, X (reprint author), Rutgers State Univ, SiCLAB, Dept Elect & Comp Engn, 94 Brett Rd, Piscataway, NJ 08854 USA. EM jzhao@ecc.rutgers.edu NR 3 TC 25 Z9 25 U1 0 U2 6 PU IEE-INST ELEC ENG PI HERTFORD PA MICHAEL FARADAY HOUSE SIX HILLS WAY STEVENAGE, HERTFORD SG1 2AY, ENGLAND SN 0013-5194 J9 ELECTRON LETT JI Electron. Lett. PD OCT 13 PY 2005 VL 41 IS 21 BP 1192 EP 1193 DI 10.1049/el:20052977 PG 2 WC Engineering, Electrical & Electronic SC Engineering GA 982SH UT WOS:000233181400032 ER PT J AU Hoppel, K Bevilacqua, R Canty, T Salawitch, R Santee, M AF Hoppel, K Bevilacqua, R Canty, T Salawitch, R Santee, M TI A measurement/model comparison of ozone photochemical loss in the Antarctic ozone hole using Polar Ozone and Aerosol Measurement observations and the Match technique SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID POAM-III OZONE; LOWER STRATOSPHERE; ARCTIC WINTER; 3-DIMENSIONAL MODEL; UPPER TROPOSPHERE; BROMINE BUDGET; CHEMICAL LOSS; VORTEX; DEPLETION; CLO AB [1] The Polar Ozone and Aerosol Measurement (POAM III) instrument has provided 6 years ( 1998 to present) of Antarctic ozone profile measurements, which detail the annual formation of the ozone hole. During the period of ozone hole formation the measurement latitude follows the edge of the polar night and presents a unique challenge for comparing with model simulations. The formation of the ozone hole has been simulated by using a photochemical box model with an ensemble of trajectories, and the results were sampled at the measurement latitude for comparison with the measured ozone. The agreement is generally good but very sensitive to the model dynamics and less sensitive to changes in the model chemistry. In order to better isolate the chemical ozone loss the Match technique was applied to 5 years of data to directly calculate ozone photochemical loss rates. The measured loss rates are specific to the high solar zenith angle conditions of the POAM-Match trajectories and are found to increase slowly from July to early August and then increase rapidly until mid-September. The Match results are sensitive to the choice of meteorological analysis used for the trajectory calculations. The ECMWF trajectories yield the smallest, and perhaps most accurate, peak loss rates that can be reproduced by a photochemical model using standard JPL 2002 kinetics, assuming reactive bromine (BrOx) of 14 pptv based solely on contributions from CH3Br and halons, and without requiring ClOx to exceed the upper limit for available inorganic chlorine of 3.7 ppbv. Larger Match ozone loss rates are found for the late August and early September period if trajectories based on UKMO and NCEP analyses are employed. Such loss rates require higher values for ClO and/or BrO than can be simulated using JPL 2002 chemical kinetics and complete activation of chlorine. In these cases, the agreement between modeled and measured loss rates is significantly improved if the model employs larger ClOOCl cross sections ( e. g., Burkholder et al., 1990) and BrOx of 24 ppt which reflects significant contributions from very short-lived bromocarbons to the inorganic bromine budget. C1 USN, Res Lab, Washington, DC 20375 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP USN, Res Lab, Washington, DC 20375 USA. EM karl.hoppel@nrl.navy.mil 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 55 TC 16 Z9 16 U1 2 U2 8 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 OCT 12 PY 2005 VL 110 IS D19 AR D19304 DI 10.1029/2004JD005651 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 975TZ UT WOS:000232687000002 ER PT J AU Kleinbohl, A Bremer, H Kullmann, H Kuttippurath, J Browell, EV Canty, T Salawitch, RJ Toon, GC Notholt, J AF Kleinbohl, A Bremer, H Kullmann, H Kuttippurath, J Browell, EV Canty, T Salawitch, RJ Toon, GC Notholt, J TI Denitrification in the Arctic mid-winter 2004/2005 observed by airborne submillimeter radiometry SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID OZONE LOSS; STRATOSPHERE; WINTER; VORTEX; DEHYDRATION; AIR AB We present measurements of unusually low mixing ratios of HNO3 in the exceptionally cold Arctic vortex of late-January and early-February 2005. The measurements were obtained by the airborne submillimeter radiometer ASUR during the polar aura validation experiment (PAVE). The distribution of HNO3 inside the vortex reaches minima below 4 ppbv around 22 km altitude and maxima above 13 ppbv around 16 km altitude, with a considerable spatial variability. We estimate a vortex averaged denitrification of 3.1 +/- 0.8 ppbv around 20 km altitude, and slight renitrification below similar to 15.5 km altitude. The observed HNO3 deficit is largest (similar to 6 ppbv) near the center of the vortex, where the air masses had experienced temperatures below the NAT formation threshold for 80-100% of the previous 20 days according to back trajectories. This suggests that the main denitrification mechanism is based on sedimenting nitric acid trihydrate particles. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Bremen, Inst Environm Phys, D-28334 Bremen, Germany. NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Kleinbohl, A (reprint author), CALTECH, Jet Prop Lab, Mail Stop 183-501,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM armin.kleinboehl@jpl.nasa.gov RI Salawitch, Ross/B-4605-2009; Canty, Timothy/F-2631-2010; Notholt, Justus/P-4520-2016 OI Salawitch, Ross/0000-0001-8597-5832; Canty, Timothy/0000-0003-0618-056X; Notholt, Justus/0000-0002-3324-885X NR 20 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 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD OCT 11 PY 2005 VL 32 IS 19 AR L19811 DI 10.1029/2005GL023408 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 975TO UT WOS:000232685600002 ER PT J AU Clements, DL Farrah, D Rowan-Robinson, M Afonso, J Priddey, R Fox, M AF Clements, D. L. Farrah, D. Rowan-Robinson, M. Afonso, J. Priddey, R. Fox, M. TI Cold dust in (some) high-z supernova host galaxies SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE supernovae : general; galaxies : high-redshift; submillimetre ID DEEP SUBMILLIMETER SURVEY; ULTRALUMINOUS INFRARED GALAXIES; STAR-FORMATION HISTORY; HIGH-REDSHIFT; LOCAL UNIVERSE; SCUBA GALAXIES; IRAS GALAXIES; FIELD; POPULATION; LUMINOSITY AB We present deep submillimetre photometry for 14 galaxies at z = 0.5 that are hosts of Type la supernovae, with the aim of examining the evolution of dust mass and extinction in normal galaxies. We combine these results with our previous observations of 17 z similar to 0.5 SN1a hosts to look for any evolution in the dust content of normal galaxies between z = 0 and 0.5. The average observed-frame 850-1 mu m flux of SN1a hosts in the full sample, excluding two bright individually detected objects, is 0.44 +/- 0.22 mJy. This flux level is consistent with there being little or no evolution in the dust content, or optical extinction, of normal galaxies from z = 0 to 0.5. One galaxy, the host of SN1996cf, is detected individually, and we also present a deep Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph (STIS) image for this object. It appears to be an edge-on disc system, similar to the submillimetre bright host of SN1997ey. We thus examine the dust properties of these and one other individually detected object. Flux ratios and limits of 450-850 mu m suggest that the dust in the two brightest submillimetre sources, SN1996cf and SN1997ey, is cold, T similar to 20 K, implying that they contain a substantial mass of dust similar to 10(9) M-circle dot The presence of two bright (F-850 > 7 mJy) submillimetre sources at z similar to 0.5 in a sample of ostensibly normal galaxies is surprising, and has important implications. It supports the idea that a substantial part of the cosmic infrared background (CIB) may be produced at z < 1, while also suggesting that 'foreground' objects such as these may be a significant 'contaminant' in submillimetre surveys. Finally, we examine the overall submillimetre luminosity distribution at z = 0.5 implied by our results, and conclude that either there is substantial evolution in the submillimetre luminosity function from z = 0 to 0.5, or our submillimetre-detected sources are somehow not representative of the bulk of galaxies at this redshift. C1 Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2BW, England. CALTECH, Jet Propuls Lab, Spitzer Sci Ctr, Pasadena, CA 91125 USA. Univ Lisbon, CAAUL, Fac Ciencias, Astron Observ, P-1349018 Lisbon, Portugal. Univ Hertfordshire, Dept Phys Astron & Math, Hatfield AL10 9AB, Herts, England. RP Clements, DL (reprint author), Univ London Imperial Coll Sci Technol & Med, Blackett Lab, Prince Consort Rd, London SW7 2BW, England. EM d.clements@ic.ac.uk RI Afonso, Jose/B-5185-2013 OI Afonso, Jose/0000-0002-9149-2973 NR 42 TC 10 Z9 10 U1 1 U2 1 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD OCT 11 PY 2005 VL 363 IS 1 BP 229 EP 235 DI 10.1111/j.1365-2966.2005.09461.x PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 968NB UT WOS:000232168100022 ER PT J AU Milligan, RO Gallagher, PT Mathioudakis, M Keenan, FP Bloomfield, DS AF Milligan, R. O. Gallagher, P. T. Mathioudakis, M. Keenan, F. P. Bloomfield, D. S. TI Plasma diagnostics of active-region evolution and implications for coronal heating SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE sun : activity; sun : corona; sun : evolution; sun : UV radiation ID 3-DIMENSIONAL STEREOSCOPIC ANALYSIS; MAGNETIC-FIELD; SOLAR CORONA; LOOPS; FLUX; TEMPERATURES; PARAMETERS; SOHO/CDS; DENSITY; SYSTEM AB A detailed study is presented of the decaying solar-active region NOAA 10103 observed with the Coronal Diagnostic Spectrometer (CDS), the Michelson Doppler Imager (MDI) and the Extreme-ultraviolet Imaging Telescope (EIT) onboard the Solar and Heliospheric Observatory (SOHO). Electron-density maps formed using Si x (356.03 angstrom/347.41 angstrom) show that the density varies from similar to 10(10) cm(-3) in the active-region core to similar to 7 x 108 cm-3 at the region boundaries. Over the 5 d of observations, the average electron density fell by similar to 30 per cent. Temperature maps formed using Fe XVI (335.41 angstrom)/Fe XIV (334.18 angstrom) show electron temperatures of similar to 2.34 x 10(6) K in the active-region core and similar to 2.10 x 10(6) K at the region boundaries. Similarly to the electron density, there was a small decrease in the average electron temperature over the 5-d period. The radiative, conductive and mass-flow losses were calculated and used to determine the resultant heating rate (P-H). Radiative losses were found to dominate the active-region cooling process. As the region decayed, the heating rate decreased by almost a factor of 5 between the first and last day of observations. The heating rate was then compared to the total unsigned magnetic flux (Phi(tot) = integral dA vertical bar B-z vertical bar), yielding a power law of the form P-H similar to Phi(0.81 +/- 0.32)(tot) This result suggests that waves rather than nanoflares may be the dominant heating mechanism in this active region. C1 Queens Univ Belfast, Dept Phys & Astron, Belfast BT7 1NN, Antrim, North Ireland. NASA, Goddard Space Flight Ctr, Lab Solar & Space Phys, Greenbelt, MD 20771 USA. Univ Coll Dublin, Dept Expt Phys, Dublin 4, Ireland. NASA, Goddard Space Flight Ctr, L3 Commun GSI, Greenbelt, MD 20771 USA. RP Milligan, RO (reprint author), Queens Univ Belfast, Dept Phys & Astron, Belfast BT7 1NN, Antrim, North Ireland. EM R.Milligan@qub.ac.uk RI Bloomfield, Shaun/G-5809-2011; Gallagher, Peter/C-7717-2011 OI Bloomfield, Shaun/0000-0002-4183-9895; Gallagher, Peter/0000-0001-9745-0400 NR 38 TC 16 Z9 16 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 OCT 11 PY 2005 VL 363 IS 1 BP 259 EP 267 DI 10.1111/j.1365-2966.2005.09446.x PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 968NB UT WOS:000232168100026 ER PT J AU Yang, RQ Hill, CJ Yang, BH AF Yang, RQ Hill, CJ Yang, BH TI High-temperature and low-threshold midinfrared interband cascade lasers SO APPLIED PHYSICS LETTERS LA English DT Article ID CONTINUOUS-WAVE OPERATION; ROOM-TEMPERATURE AB A broad-area midinfrared interband cascade (IC) laser has been demonstrated with a threshold current as low as similar to 630 A/cm(2) at 300 K. Despite exhibiting a large specific thermal resistance (similar to 56 K cm(2)/kW at 172 K), the device delivered cw power near 200 mW/facet at 500 mA and at 83 K and lased in cw mode up to 172 K. A 0.5-mm-long laser delivered cw power of similar to 253 mW/facet at 400 mA and at 82 K, and had power efficiency as high as 26% at similar to 80 K. Narrow mesa stripe IC lasers had relatively higher threshold current density, yet lased at temperatures up to 237 and 350 K in cw and pulsed modes, respectively. The feasibility of cw operation at higher temperatures and directions for improving IC laser performance are discussed based on the experimental data. (C) 2005 American Institute of Physics. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Yang, RQ (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM rui.q.yang@jpl.nasa.gov NR 12 TC 54 Z9 55 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 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD OCT 10 PY 2005 VL 87 IS 15 AR 151109 DI 10.1063/1.2103387 PG 3 WC Physics, Applied SC Physics GA 972GL UT WOS:000232442200009 ER PT J AU Cohn, JD Kadota, K AF Cohn, JD Kadota, K TI Uncertainties in the Sunyaev-Zel'dovich-selected cluster angular power spectrum SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmic microwave background; cosmological parameters; galaxies : clusters : general ID DARK-MATTER HALOES; HUBBLE VOLUME SIMULATIONS; LARGE-SCALE BIAS; X-RAY-PROPERTIES; GALAXY CLUSTERS; RELATIVISTIC CORRECTIONS; COSMOLOGICAL CONSTRAINTS; TEMPERATURE PROFILE; POINT SOURCES; MASS AB Large Sunyaev- Zel'dovich - selected galaxy cluster surveys are beginning imminently. We compare the dependence of the galaxy cluster angular power spectrum on cosmological parameters, different modeling assumptions, and statistical observational errors. We quantify the degeneracies between theoretical assumptions such as the mass function and cosmological parameters such as sigma(8). We also identify a rough scaling behavior of this angular power spectrum with sigma(8) alone. C1 Space Sci Lab, Berkeley, CA 94720 USA. Theoret Astrophys Ctr, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Fermilab Natl Accelerator Lab, NASA, Fermilab Astrophys Ctr, Batavia, IL 60510 USA. RP Space Sci Lab, 7 Gauss Way, Berkeley, CA 94720 USA. EM jcohn@astron.berkeley.edu; kadota@fnal.gov NR 71 TC 3 Z9 3 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 OCT 10 PY 2005 VL 632 IS 1 BP 1 EP 14 DI 10.1086/432706 PN 1 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 971EZ UT WOS:000232366000001 ER PT J AU Immler, S Fesen, RA Van Dyk, SD Weiler, KW Petre, R Lewin, WHG Pooley, D Pietsch, W Aschenbach, B Hammell, MC Rudie, GC AF Immler, S Fesen, RA Van Dyk, SD Weiler, KW Petre, R Lewin, WHG Pooley, D Pietsch, W Aschenbach, B Hammell, MC Rudie, GC TI Late-time X-ray, UV, and optical monitoring of supernova 1979C SO ASTROPHYSICAL JOURNAL LA English DT Article DE circumstellar matter; galaxies : individual (M100, NGC 4321); supernovae : individual (SN 1979C); ultraviolet : ISM; X-rays : general; X-rays : individual (M100, NGC 4321, SN1979C); X-rays : ISM ID PRESUPERNOVA MASS-LOSS; SN 1979C; CIRCUMSTELLAR INTERACTION; RADIO OBSERVATIONS; II SUPERNOVAE; GALAXY M100; EMISSION; CHANDRA; SN1979C; PROGENITOR AB We present results from observations of supernova (SN) 1979C with the Newton X-Ray Multi-Mirror (XMM-Newton) mission in X-rays and in UV, archival X-ray, and Hubble Space Telescope (HST) data, and follow-up ground-based optical imaging. The XMM-Newton MOS spectrum shows the best-fit two-temperature thermal plasma emission characteristics of both the forward (kT(high) = 4:1(-2.4)(+76) keV) and reverse shock (kT(low) = 0.79(-0.17)(+0.24) keV) with no intrinsic absorption. The long-term X-ray light curve, constructed from all X-ray data available, reveals that SN 1979C is still radiating at a flux level similar to that detected by ROSAT in 1995, showing no sign of a decline over the last 6 years, some 16-23 yr after its outburst. The high inferred X-ray luminosity (L(0.3-2) = 8 x 10(38) ergs s(-1)) is caused by the interaction of the SN shock with dense circumstellar matter, likely deposited by a strong stellar wind from the progenitor with a high mass- loss rate of. M approximate to 1.5 x 10(-4) M(circle dot) yr(-1) (v(w)/10 km s(-1)). The X-ray data support a strongly decelerated shock and show a mass-loss rate history that is consistent with a constant progenitor mass-loss rate and wind velocity over the past greater than or similar to 16,000 yr in the stellar evolution of the progenitor. We find a best-fit circumstellar medium (CSM) density profile of rho(CSM) proportional to r(-s) with index s less than or similar to 1.7 and high CSM densities (greater than or similar to 10(4) cm(-3)) out to large radii from the site of the explosion (r greater than or similar to 4 x 10(17) cm). Using XMM-Newton Optical Monitor data, we further detect a pointlike optical/UV source consistent with the position of SN 1979C, with B-, U-, and UVW1-band luminosities of 5, 7, and 9 x 10(36) ergs s(-1), respectively. The young stellar cluster in the vicinity of the SN, as imaged by the HSTand follow- up ground- based optical imaging, can only provide a fraction of the total observed flux, so that a significant contribution to the output likely arises from the strong interaction of SN 1979C with dense CSM. C1 NASA, Goddard Space Flight Ctr, Explorat Universe Div, Xray Astrophys Lab, Greenbelt, MD 20771 USA. Univ Space Res Assoc, Columbia, MD 21044 USA. Dartmouth Coll, Dept Phys & Astron, Hanover, NH 03755 USA. CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA. USN, Res Lab, Washington, DC 20375 USA. MIT, Ctr Space Res, Cambridge, MA 02139 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Max Planck Inst Extraterr Phys, D-85741 Garching, Germany. RP Immler, S (reprint author), NASA, Goddard Space Flight Ctr, Explorat Universe Div, Xray Astrophys Lab, Code 662, Greenbelt, MD 20771 USA. EM immler@milkyway.gsfc.nasa.gov OI Van Dyk, Schuyler/0000-0001-9038-9950 NR 29 TC 15 Z9 15 U1 0 U2 3 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 OCT 10 PY 2005 VL 632 IS 1 BP 283 EP 293 DI 10.1086/432869 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 971EZ UT WOS:000232366000020 ER PT J AU Hudgins, DM Bauschlicher, CW Allamandola, LJ AF Hudgins, DM Bauschlicher, CW Allamandola, LJ TI Variations in the peak position of the 6.2 mu m interstellar emission feature: A tracer of N in the interstellar polycyclic aromatic hydrocarbon population SO ASTROPHYSICAL JOURNAL LA English DT Article DE astrochemistry; dust, extinction; infrared : ISM; ISM : lines and bands; ISM : molecules; molecular processes ID UNIDENTIFIED INFRARED-EMISSION; LARGE MOLECULES; ASTROPHYSICAL IMPLICATIONS; ABSORPTION-SPECTROSCOPY; GALACTIC EMISSION; RADICAL CATIONS; PAH MOLECULES; NITROGEN ATOM; SMALL GRAINS; SPECTRA AB This paper presents the results of an investigation of the molecular characteristics that underlie the observed peak position and profile of the nominal 6.2 mu m interstellar emission band generally attributed to the CC stretching vibrations of polycyclic aromatic hydrocarbons (PAHs). It begins with a summary of recent experimental and theoretical studies of the spectroscopic properties of large (>30 carbon atoms) PAH cations as they relate to this aspect of the astrophysical problem. It then continues with an examination of the spectroscopic properties of a number of PAH variants within the context of the interstellar 6.2 mu m emission, beginning with a class of compounds known as polycyclic aromatic nitrogen heterocycles (PANHs; PAHs with one or more nitrogen atoms substituted into their carbon skeleton). In this regard, we summarize the results of recent relevant experimental studies involving a limited set of small PANHs and their cations and then report the results of a comprehensive computational study that extends that work to larger PANH cations including many nitrogen-substituted variants of coronene(+) (C24H12+), ovalene(+) (C32H14+), circumcoronene(+) (C54H18+), and circum-circumcoronene(+) (C96H24+). Finally, we report the results of more focused computational studies of selected representatives from a number of other classes of PAH variants that share one or more of the key attributes of the PANH species studied. These alternative classes of PAH variants include (1) oxygen- and silicon-substituted PAH cations; (2) PAH-metal ion complexes (metallocenes) involving the cosmically abundant elements magnesium and iron; and ( 3) large, asymmetric PAH cations. Overall, the studies reported here demonstrate that increasing PAH size alone is insufficient to account for the position of the shortest wavelength interstellar 6.2 mu m emission bands, as had been suggested by earlier studies. On the other hand, this work reveals that substitution of one or more nitrogen atoms within the interior of the carbon skeleton of a PAH cation induces a significant blueshift in the position of the dominant CC stretching feature of these compounds that is sufficient to account for the position of the interstellar bands. Subsequent studies of the effects of substitution by other heteroatoms (O and Si), metal ion complexation (Fe+, Mg+, and Mg2+), and molecular symmetry variation - all of which fail to reproduce the blueshift observed in the PANH cations - indicate that N appears to be unique in its ability to accommodate the position of the interstellar 6.2 mu m bands while simultaneously satisfying the other constraints of the astrophysical problem. This result implies that the peak position of the interstellar feature near 6.2 mu m traces the degree of nitrogen substitution in the population, that most of the PAHs responsible for the interstellar IR emission features incorporate nitrogen within their aromatic networks, and that a lower limit of 1%-2% of the cosmic nitrogen is sequestered within the interstellar PAH population. Finally, in view of the ubiquity and abundance of interstellar PAHs and the permanent dipoles and distinctive electronic structures of these nitrogen-substituted variants, this work impacts a wide range of observational phenomena outside of the infrared region of the spectrum including the forest of unidentified molecular rotational features and the anomalous Galactic foreground emission in the microwave, and the diffuse interstellar bands (DIBs) and other structure in the interstellar extinction curve in the ultraviolet/visible. These astrophysical ramifications are discussed, and the dipole moments and rotational constants are tabulated to facilitate further investigations of the astrophysical role of nitrogen-substituted aromatic compounds. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. NASA, Ames Res Ctr, Space Technol Div, Moffett Field, CA 94035 USA. RP Hudgins, DM (reprint author), NASA, Ames Res Ctr, MS 245-6, Moffett Field, CA 94035 USA. EM dhudgins@mail.arc.nasa.gov NR 72 TC 139 Z9 139 U1 2 U2 30 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 OCT 10 PY 2005 VL 632 IS 1 BP 316 EP 332 DI 10.1086/432495 PN 1 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 971EZ UT WOS:000232366000023 ER PT J AU Remijan, AJ Hollis, JM Lovas, FJ Plusquellic, DF Jewell, PR AF Remijan, AJ Hollis, JM Lovas, FJ Plusquellic, DF Jewell, PR TI Interstellar isomers: The importance of bonding energy differences SO ASTROPHYSICAL JOURNAL LA English DT Article DE astrochemistry ISM : abundances; ISM : clouds; ISM : individual (Sagittarius B2(N)); ISM : molecules; radio lines : ISM ID SPECTRAL-LINE SURVEY; CORRELATED MOLECULAR CALCULATIONS; GAUSSIAN-BASIS SETS; MICROWAVE-SPECTRA; ASTROPHYSICAL INTEREST; SAGITTARIUS B2; RESOLUTION OBSERVATIONS; OBSERVATIONAL DATA; ORGANIC-MOLECULES; VINYL ISOCYANIDE AB We present strong detections of methyl cyanide (CH3CN), vinyl cyanide (CH2CHCN), ethyl cyanide (CH3CH2CN), and cyanodiacetylene (HC4CN) molecules with the Green Bank Telescope (GBT) toward the Sgr B2(N) molecular cloud. Attempts to detect the corresponding isocyanide isomers were only successful in the case of methyl isocyanide (CH3NC) for its J(K) = 1(0)-0(0) transition, which is the first interstellar report of this line. To determine the spatial distribution of CH3NC, we used archival Berkeley-Illinois-Maryland Association (BIMA) array data for the J(K) = 4(K)-3(K) (K = 0-3) transitions, but no emission was detected. From ab initio calculations, the bonding energy difference between the cyanide and isocyanide molecules is >8500 cm(-1) (>12,000 K). Thus, cyanides are the more stable isomers and would likely be formed more preferentially over their isocyanide counterparts. That we detect CH3NC emission with a single antenna ( Gaussian beam size Omega(B) = 1723 arcsec(2)) but not with an interferometer (Omega w = 192 arcsec(2)) strongly suggests that CH3NC has a widespread spatial distribution toward the Sgr B2(N) region. Other investigators have shown that CH3CN is present both in the LMH hot core of Sgr B2(N) and in the surrounding medium, while we have shown that CH3NC appears to be deficient in the LMH hot core. Thus, large-scale, nonthermal processes in the surrounding medium may account for the conversion of CH3CN to CH3NC, while the LMH hot core, which is dominated by thermal processes, does not produce a significant amount of CH3NC. Ice analog experiments by other investigators have shown that radiation bombardment of CH3CN can produce CH3NC, thus supporting our observations. We conclude that isomers separated by such large bonding energy differences are distributed in different interstellar environments, making the evaluation of column density ratios between such isomers irrelevant unless it can be independently shown that these species are cospatial. C1 NASA, Goddard Space Flight Ctr, Computat & Informat Sci & Technol Off, Greenbelt, MD 20771 USA. Natl Inst Stand & Technol, Opt Technol Div, Gaithersburg, MD 20899 USA. Natl Radio Astron Observ, Green Bank, WV 24944 USA. RP Remijan, AJ (reprint author), NASA, Goddard Space Flight Ctr, Computat & Informat Sci & Technol Off, Code 606, Greenbelt, MD 20771 USA. NR 41 TC 45 Z9 46 U1 0 U2 12 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 OCT 10 PY 2005 VL 632 IS 1 BP 333 EP 339 DI 10.1086/432908 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 971EZ UT WOS:000232366000024 ER PT J AU Kim, JS Hines, DC Backman, DE Hillenbrand, LA Meyer, MR Rodmann, J Moro-Martin, A Carpenter, JM Silverstone, MD Bouwman, J Mamajek, EE Wolf, S Malhotra, R Pascucci, I Najita, J Padgett, DL Henning, T Brooke, TY Cohen, M Strom, SE Stobie, EB Engelbracht, CW Gordon, KD Misselt, K Morrison, JE Muzerolle, J Su, KYL AF Kim, JS Hines, DC Backman, DE Hillenbrand, LA Meyer, MR Rodmann, J Moro-Martin, A Carpenter, JM Silverstone, MD Bouwman, J Mamajek, EE Wolf, S Malhotra, R Pascucci, I Najita, J Padgett, DL Henning, T Brooke, TY Cohen, M Strom, SE Stobie, EB Engelbracht, CW Gordon, KD Misselt, K Morrison, JE Muzerolle, J Su, KYL TI Formation and evolution of planetary systems: Cold outer disks associated with sun-like stars SO ASTROPHYSICAL JOURNAL LA English DT Article DE circumstellar matter; planetary systems : formation; stars : formation ID SPITZER-SPACE-TELESCOPE; MULTIBAND IMAGING PHOTOMETER; SPECTRAL IRRADIANCE CALIBRATION; INFRARED ARRAY CAMERA; EDGEWORTH-KUIPER BELT; MAIN-SEQUENCE STARS; SOLAR-TYPE STARS; DEBRIS DISKS; DUSTY DEBRIS; REDUCTION ALGORITHMS AB We present the discovery of debris systems around three Sun-like stars based on observations performed with the Spitzer Space Telescope as part of a Legacy Science Program, "The Formation and Evolution of Planetary Systems'' ( FEPS). We also confirm the presence of debris around two other stars. All the stars exhibit infrared emission in excess of the expected photospheres in the 70 mu m band but are consistent with photospheric emission at <= 33 mu m. This restricts the maximum temperature of debris in equilibrium with the stellar radiation to T < 70 K. We find that these sources are relatively old in the FEPS sample, in the age range 0.7 - 3 Gyr. On the basis of models of the spectral energy distributions, we suggest that these debris systems represent materials generated by collisions of planetesimal belts. We speculate on the nature of these systems through comparisons to our own Kuiper Belt, and on the possible presence of planet( s) responsible for stirring the system and ultimately releasing dust through collisions. We further report observations of a nearby star HD 13974 ( d 11 pc) that are indistinguishable from a bare photosphere at both 24 and 70 mu m. The observations place strong upper limits on the presence of any cold dust in this nearby system (L-IR/L-* < 10 (-5.2)). C1 Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Space Sci Inst, Boulder, CO 80303 USA. NASA, Ames Res Ctr, SOFIA, Moffett Field, CA 94035 USA. CALTECH, Dept Astron, Pasadena, CA 91125 USA. Max Planck Inst Astron, D-69117 Heidelberg, Germany. Princeton Univ, Princeton, NJ 08540 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Arizona, Dept Planetary Sci, Tucson, AZ 85721 USA. Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. Natl Opt Astron Observ, Tucson, AZ 85719 USA. CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA. Univ Calif Berkeley, Berkeley, CA 94720 USA. RP Kim, JS (reprint author), Univ Arizona, Steward Observ, 933 N Cherry Ave, Tucson, AZ 85721 USA. OI Malhotra, Renu/0000-0002-1226-3305; Su, Kate/0000-0002-3532-5580 NR 57 TC 62 Z9 62 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 OCT 10 PY 2005 VL 632 IS 1 BP 659 EP 669 DI 10.1086/432863 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 971EZ UT WOS:000232366000045 ER PT J AU Vermont, EF Satterfield, EA AF Vermont, EF Satterfield, EA TI Cover: Southern Africa, 2 February 2002 to 16 May 2002, moderate resolution imaging spectroradiometer (MODIS) 500m land surface reflectance SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article C1 Univ Maryland, Dept Geog, College Pk, MD 20742 USA. NASA Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Vermont, EF (reprint author), Univ Maryland, Dept Geog, 2181 LeFrak Hall, College Pk, MD 20742 USA. EM eric@kratmos.gsfc.nasa.gov NR 4 TC 0 Z9 0 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD OCT 10 PY 2005 VL 26 IS 19 BP 4137 EP 4139 PG 3 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA 985AL UT WOS:000233348400001 ER PT J AU Privette, JL Roy, DP AF Privette, JL Roy, DP TI Southern Africa as a remote sensing test bed: the SAFARI 2000 Special Issue overview SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article ID TIME-SERIES; RAINFALL; KALAHARI; OSCILLATION; VARIABILITY; ECOSYSTEM; CAMPAIGN; CLIMATE; TRENDS; COVER AB NASA's flagship Earth Observing System (EOS) Terra satellite was launched in 1999 and began sensing in March 2000 coincident with the first major field campaign of the Southern Africa Regional Science Initiative (SAFARI 2000). Terra's five sensors were used to support SAFARI 2000 studies on the southern African environment, and SAFARI 2000's ground, aircraft and independent satellite data sets were used in turn to validate and improve the remote sensing products derived from Terra. In this article, we review southern Africa's natural and cultural features that we believe formed an optimal environment in which to test the EOS program (including new sensors, products, validation, scientific research, education and outreach). Through the course of the text, we reference and summarize the articles in the SAFARI 2000 Special Issue to highlight the natural links between remote sensing science and the subcontinent's characteristics. We also note contemporary forces of change in the southern Africa landscape whose impacts will challenge the remote monitoring capabilities of future sensors and scientists. The article concludes with a brief description of SAFARI 2000 data resources and access provisions. C1 NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Greenbelt, MD 20771 USA. Univ Maryland, Dept Geog, College Pk, MD 20742 USA. NASAs Goddard Space Flight Ctr, College Pk, MD 20742 USA. RP NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Code 661, Greenbelt, MD 20771 USA. EM jeff.privette@nasa.gov RI Privette, Jeffrey/G-7807-2011 OI Privette, Jeffrey/0000-0001-8267-9894 NR 68 TC 7 Z9 7 U1 0 U2 2 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 2-4 PARK SQUARE, MILTON PARK, ABINGDON OR14 4RN, OXON, ENGLAND SN 0143-1161 EI 1366-5901 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD OCT 10 PY 2005 VL 26 IS 19 BP 4141 EP 4158 PG 18 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA 985AL UT WOS:000233348400002 ER PT J AU Eckardt, FD Kuring, N AF Eckardt, FD Kuring, N TI SeaWiFS identifies dust sources in the Namib Desert SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article AB Mineral dust sources were identified in Sea-viewing Wide Field-of-view Sensor (SeaWiFS) images along the south-west coast of Africa. Up to 150 dust plumes were observed over a 3 year period, and these are linked to sources that are either salt pans or dry river beds in the Namib Desert. This demonstrates that dust supply is maintained by fluvial landforms and associated hydrology. This paper highlights the need to look in more detail at source areas around the globe, as this will further our understanding of dust- production processes. C1 Univ Cape Town, Dept Environm & Geog Sci, ZA-7701 Rondebosch, South Africa. NASA GSFC, Greenbelt, MD 20771 USA. RP Eckardt, FD (reprint author), Univ Cape Town, Dept Environm & Geog Sci, Private Bag, ZA-7701 Rondebosch, South Africa. EM feckardt2001@yahoo.com RI Eckardt, Frank/N-3682-2015 OI Eckardt, Frank/0000-0003-0200-7110 NR 11 TC 27 Z9 27 U1 0 U2 4 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD OCT 10 PY 2005 VL 26 IS 19 BP 4159 EP 4167 PG 9 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA 985AL UT WOS:000233348400003 ER PT J AU Hao, WM Ward, DE Susott, RA Babbitt, RE Nordgren, BL Kaufman, YJ Holben, BN Giles, DM AF Hao, WM Ward, DE Susott, RA Babbitt, RE Nordgren, BL Kaufman, YJ Holben, BN Giles, DM TI Comparison of aerosol optical thickness measurements by MODIS, AERONET sun photometers, and Forest Service handheld sun photometers in southern Africa during the SAFARI 2000 campaign SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article ID SATELLITE-OBSERVATIONS; TEMPORAL DISTRIBUTION; SURFACE REFLECTANCE; VEGETATION FIRE; DRY SEASON; BIOMASS; LAND; VARIABILITY; VALIDATION; INSTRUMENT AB The Moderate Resolution Imaging Spectroradiometer (MODIS) instrument on the NASA Terra satellite has been used to monitor aerosol optical thickness (AOT, tau) daily at 10 km x 10 km resolution worldwide since August 2000. This information, together with the locations of active fires detected by the MODIS instrument, is essential for understanding the seasonal trends and interannual variability of fires and their impacts on air pollution, atmospheric chemistry, and global climate. We compared aerosol optical thickness derived from MODIS, five automated sun photometers of the Aerosol Robotic Network (AERONET), and 38 Forest Service (FS) handheld sun photometers in western Zambia from 20 August to 20 September 2000. Aerosol optical thicknesses derived from AERONET sun photometers and FS sun photometers were also compared in the same region between mid-June and late September 2000. Our objectives were to validate the AOT measurements by MODIS and to investigate the factors that affect AOT measurements. We demonstrated that in the regions of intense biomass burning, MODIS aerosol optical thickness was consistently 40-50% lower at 470, 550, and 660 nm compared with ground-based AOT measurements by automated and handheld sun photometers and airborne measurements by NASA Ames Airborne Tracking 14-channel Sunphotometers (AATS-14). The satellite look angles can influence the MODIS AOT values, with the actual MODIS AOT values being as much as 0.06 higher than model-calculated MODIS AOT values on the right edge of the MODIS scene. This phenomenon may be due to error in the assumed aerosol scattering phase function or surface directional properties. Density of vegetation cover can also affect MODIS measurements of aerosol optical thickness. C1 USDA Forest Serv, Rocky Mt Res Stn, Fire Sci Lab, Missoula, MT 59807 USA. Enviropyron LLC, White Salmon, WA 98672 USA. NASA Goddard Space Flight Ctr, Lab Atmospheres, Greenbelt, MD 20771 USA. NASA Goddard Space Flight Ctr, Biospher Sci Branch, Greenbelt, MD 20771 USA. Sci Syst & Applicat Inc, Lanham, MD 20706 USA. RP USDA Forest Serv, Rocky Mt Res Stn, Fire Sci Lab, Missoula, MT 59807 USA. EM whao@fs.fed.us NR 21 TC 14 Z9 17 U1 0 U2 5 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 2-4 PARK SQUARE, MILTON PARK, ABINGDON OR14 4RN, OXON, ENGLAND SN 0143-1161 EI 1366-5901 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD OCT 10 PY 2005 VL 26 IS 19 BP 4169 EP 4183 PG 15 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA 985AL UT WOS:000233348400004 ER PT J AU Roy, DP Landmann, T AF Roy, DP Landmann, T TI Characterizing the surface heterogeneity of fire effects using multi-temporal reflective wavelength data SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article ID VEGETATION INDEXES; SAVANNA ECOSYSTEMS; SOUTH-AFRICA; BIOMASS; FOREST; DYNAMICS AB The relationship between changes observed in multi-temporal remotely sensed data and disturbance processes are increasingly being studied in support of various land process modelling and management decision applications. The possibility of mapping both the location and degree of change and retrieving information concerning the disturbance process are primary goals. This paper studies changes in reflective wavelength data caused by the action of fire. We consider the heterogeneity of fire effects in terms of the fraction of the observation that burned (f) and the combustion completeness (cc). A spectral mixture model and field and satellite observations of prescribed fires are used to examine the relationship between change in reflectance, and cc and f. The prescribed fires were lit in different South African savannah types during the SAFARI 2000 dry season campaign. Implications for the development of methods to retrieve cc and f, and for the development of methods to map the spatial extent of fire-affected areas with known detection capabilities are discussed. C1 Univ Maryland, Dept Geog, College Pk, MD 20742 USA. NASA Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. CSIR Environm, Pretoria, South Africa. RP Roy, DP (reprint author), Univ Maryland, Dept Geog, College Pk, MD 20742 USA. EM droy@kratmos.gsfc.nasa.gov NR 47 TC 35 Z9 38 U1 0 U2 4 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD OCT 10 PY 2005 VL 26 IS 19 BP 4197 EP 4218 PG 22 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA 985AL UT WOS:000233348400006 ER PT J AU Morisette, JT Giglio, L Csiszar, I Justice, CO AF Morisette, JT Giglio, L Csiszar, I Justice, CO TI Validation of the MODIS active fire product over Southern Africa with ASTER data SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article ID ACCURACY; CLASSIFICATION; RADIOMETER AB This paper describes the use of high-spatial-resolution ASTER data to determine the accuracy of the moderate- resolution MODIS active fire product. Our main objective was to develop a methodology to use ASTER data for quantitative evaluation of the MODIS active fire product and to apply it to fires in southern Africa during the 2001 burning season. We utilize 18 ASTER scenes distributed throughout the Southern Africa region covering the time period 5 August 2001 to 6 October 2001. The MODIS fire product is characterized through the use of logistic regression models to establish a relationship between the binary MODIS 'fire'/'no fire' product and summary statistics derived from ASTER data over the coincident MODIS pixel. Probabilities of detection are determined as a function of the total number of ASTER fires and Moran's I, a measure of the spatial heterogeneity of fires within the MODIS pixel. The statistical analysis is done for versions 3 and 4 of the MODIS fire-detection algorithm. It is shown that the algorithm changes have a positive effect on the fire-product accuracy. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Maryland, Dept Geog, College Pk, MD 20742 USA. RP Morisette, JT (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM jeff.morisette@nasa.gov RI Csiszar, Ivan/D-2396-2010 NR 29 TC 94 Z9 98 U1 1 U2 12 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD OCT 10 PY 2005 VL 26 IS 19 BP 4239 EP 4264 PG 26 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA 985AL UT WOS:000233348400008 ER PT J AU Roy, DP Frost, PGH Justice, CO Landmann, T Le Roux, JL Gumbo, K Makungwa, S Dunham, K Du Toit, R Mhwandagara, K Zacarias, A Tacheba, B Dube, OP Pereira, JMC Mushove, P Morisette, JT Vannan, SKS Davies, D AF Roy, DP Frost, PGH Justice, CO Landmann, T Le Roux, JL Gumbo, K Makungwa, S Dunham, K Du Toit, R Mhwandagara, K Zacarias, A Tacheba, B Dube, OP Pereira, JMC Mushove, P Morisette, JT Vannan, SKS Davies, D TI The Southern Africa Fire Network (SAFNet) regional burned-area product-validation protocol SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article ID ATMOSPHERIC EMISSIONS; SAVANNA ECOSYSTEMS; VEGETATION FIRE; SATELLITE DATA; CLIMATE-CHANGE; SAFARI 2000; BIOMASS; MODIS; REFLECTANCE; AUSTRALIA AB The development of appropriate validation techniques is critical to assess uncertainties associated with satellite-data-based products, to identify needed product improvements and to allow products to be used appropriately. At regional to global scales, there are several outstanding issues in the development of robust validation methodologies, including the need to increase the quality and economy of product validation by developing and promoting international validation standards and protocols. This paper describes a protocol developed to validate a regional southern Africa burned- area product derived from Moderate Resolution Imaging Spectroradiometer (MODIS) 500 m time series data. The protocol is based upon interpretations by members of the Southern Africa Fire Network (SAFNet) of multitemporal Landsat Enhanced Thematic Mapper plus (ETM +) data to derive maps of the location and approximate date of burning. The validation data are derived using Landsat ETM + scenes distributed to encompass representative regional variation in the conditions for which the MODIS burned-area product was generated and to capture the more important factors that influence product performance. The protocol was developed by consensus to ensure inter- comparison of the independent data derived by the different SAFNet members and to allow these data to be scaled up to provide regional validation of the MODIS burned-area product. Biomass burning in southern Africa, the ETM + sampling rationale, the interpretation and mapping approach, SAFNet member fire activities, and illustrative 2001 results and difficulties encountered with the protocol are described. C1 Univ Maryland, Dept Geog, College Pk, MD 20742 USA. NASA Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Zimbabwe, Inst Environm Studies, Harare, Zimbabwe. CSIR Environm, ZA-0006 Pretoria, South Africa. Forestry Commiss, Bulawayo, Zimbabwe. Univ Malawi, Bunda Coll Agr, Lilongwe, Malawi. WWF So African Reg Programme Off, Harare, Zimbabwe. Geospatial Solut Zimbabwe, Harare, Zimbabwe. Minist Agr & Desenvolvimento Rural, Direccao Nacl Florstas & Fauna Bravia, Maputo, Mozambique. Univ Botswana, Harry Oppenheimer Okavango Res Ctr, Maun, Botswana. Univ Botswana, Dept Environm Sci, Gaborone, Botswana. Trop Res Inst, Cartog Ctr, P-1300142 Lisbon, Portugal. RP Roy, DP (reprint author), Univ Maryland, Dept Geog, College Pk, MD 20742 USA. EM droy@kratmos.gsfc.nasa.gov RI Pereira, Jose/I-1283-2014 OI Pereira, Jose/0000-0003-2583-3669 NR 68 TC 48 Z9 50 U1 0 U2 10 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD OCT 10 PY 2005 VL 26 IS 19 BP 4265 EP 4292 PG 28 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA 985AL UT WOS:000233348400009 ER PT J AU Huemmrich, KF Privette, JL Mukelabai, M Myneni, RB Knyazikhin, Y AF Huemmrich, KF Privette, JL Mukelabai, M Myneni, RB Knyazikhin, Y TI Time-series validation of MODIS land biophysical products in a Kalahari woodland, Africa SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article ID LEAF-AREA INDEX; PHOTOSYNTHETICALLY ACTIVE RADIATION; CANOPY PAR ABSORPTANCE; INITIATIVE SAFARI 2000; SAIL MODEL; MISR DATA; VEGETATION; SATELLITE; REFLECTANCE; PHENOLOGY AB Monthly measurements of leaf area index (LAI) and the fraction of absorbed photosynthetically active radiation (f(APAR)) taken at approximately monthly intervals were collected along three 750 m transects in a Kalahari woodland near Mongu in western Zambia. These data were compared with MODIS NDVI (MOD13, Collection 3) and MODIS LAI and f(APAR) products (MOD15, Collection 3) over a 2 year period (2000 - 2002). MODIS and ground- measured LAI values corresponded well, while there was a significant bias between MODIS and ground-measured f(APAR) even though both MODIS variables are produced from the same algorithm. Solar zenith angle effects, differences between intercepted and absorbed photosynthetically active radiation, and differences in measurement of fAPAR (photon counts versus energy) were examined and rejected as explanations for the discrepancies between MODIS and groundmeasured f(APAR). Canopy reflectance model simulations produced different values of f(APAR) with the same LAI when canopy cover was varied, indicating that errors in the estimation of canopy cover in the MODIS algorithm due to the land cover classification used are a possible cause of the f(APAR) discrepancy. This is one of the first studies of MODIS land product performance in a time-series context. Despite a bias in f(APAR), our results demonstrate that the woodland canopy phonology is captured in the MODIS product. C1 Univ Maryland, Joint Ctr Earth Syst Technol, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Greenbelt, MD 20771 USA. Meteorol Off, Mongu, Zambia. Boston Univ, Dept Geog, Boston, MA 02215 USA. RP Huemmrich, KF (reprint author), Univ Maryland, Joint Ctr Earth Syst Technol, Code 661, Greenbelt, MD 20771 USA. EM karl.huemmrich@gsfc.nasa.gov RI Privette, Jeffrey/G-7807-2011; Myneni, Ranga/F-5129-2012 OI Privette, Jeffrey/0000-0001-8267-9894; NR 31 TC 84 Z9 92 U1 3 U2 26 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD OCT 10 PY 2005 VL 26 IS 19 BP 4381 EP 4398 PG 18 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA 985AL UT WOS:000233348400014 ER PT J AU Rawlins, MA McDonald, KC Frolking, S Lammers, RB Fahnestock, M Kimball, JS Vorosmarty, CJ AF Rawlins, MA McDonald, KC Frolking, S Lammers, RB Fahnestock, M Kimball, JS Vorosmarty, CJ TI Remote sensing of snow thaw at the pan-Arctic scale using the SeaWinds scatterometer SO JOURNAL OF HYDROLOGY LA English DT Article DE snow; scatterometer; SeaWinds; runoff; pan-Arctic ID AIR-TEMPERATURE; SEA-ICE; RADAR; REANALYSIS; DISCHARGE; BOREAL; RUNOFF; SYSTEM; MODEL AB Remotely sensed estimates of snow thaw offer the potential of more complete spatial coverage across remote, undersampled areas such as the terrestrial Arctic drainage basin. We compared the timing of spring thaw determined from approximately 25 km resolution daily radar backscatter data with observed daily river discharge time series and model simulated snow water content data for 52 basins (5000-10,000 km(2)) across Canada and Alaska for the spring of 2000. Algorithms for identifying critical thaw transitions were applied to daily backscatter time series from the SeaWinds scatterometer aboard NASA QuikSCAT, the observed discharge data, and model snow water from the pan-Arctic Water Balance Model (PWBM). Radar-derived thaw shows general agreement with discharge increases (Mean Absolute Difference, MAD= 21 days, r=0.45), with better agreement (16 days) in basins with moderate-high runoff due to snow thaw. Even better agreement is noted when comparing the scatterometer-derived primary thaw timing with model simulated snow water increase (MAD= 14 days, r=0.75). Good correspondence is found across higher latitude basins in western Canada and Alaska, while the largest discrepancies appear at the driest watersheds with lower snow and daily discharge amounts. Extending this analysis to the entire pan-Arctic drainage basin, we compared scatterometer-derived date of the primary (maximum) thaw with the timing of simulated snow water increases from the PWBM. Good agreement is found across much of the pan-Arctic; discrepancies for over half of the analyzed grid cells are less than one week. MADs are 11.7 days for the Arctic basin in Eurasian and 15.1 days across North America. Mean biases are low; 2.1 and -3.1 days for Eurasia and North America, respectively. Stronger backscatter response (high signal-low noise) is noted with higher seasonal snow accumulation, low to moderate tree cover and low topographic complexity. Although our results show inconsistent performance along coastal regions and warmer southerly parts of the study domain, active radar instruments such as SeaWinds offer the potential for monitoring high-latitude snow thaw at spatial scales appropriate for pan-Arctic applicationsin near real time. Applications include hydrological model verification, analysis of lags between snow thaw and river response, and determination of large-scale snow extent. (c) 2005 Elsevier B.V. All rights reserved. C1 Univ New Hampshire, Water Syst Anal Grp, Inst Study Earth Oceans & Space, Durham, NH 03824 USA. CALTECH, Jet Propuls Lab, Pasadena, CA 91125 USA. Univ New Hampshire, Dept Earth Sci, Durham, NH 03824 USA. Univ Montana, Sch Forestry, NTSG, Missoula, MT 59812 USA. RP Univ New Hampshire, Water Syst Anal Grp, Inst Study Earth Oceans & Space, Durham, NH 03824 USA. EM rawlins@eos.sr.unh.edu RI Fahnestock, Mark/N-2678-2013 NR 45 TC 33 Z9 34 U1 3 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-1694 EI 1879-2707 J9 J HYDROL JI J. Hydrol. PD OCT 10 PY 2005 VL 312 IS 1-4 BP 294 EP 311 DI 10.1016/j.jhydrol.2004.12.018 PG 18 WC Engineering, Civil; Geosciences, Multidisciplinary; Water Resources SC Engineering; Geology; Water Resources GA 975OT UT WOS:000232672500019 ER PT J AU Bataille, F Rubinstein, R Hussaini, MY AF Bataille, F Rubinstein, R Hussaini, MY TI Eddy viscosity and diffusivity modeling SO PHYSICS LETTERS A LA English DT Article DE eddy viscosity; eddy diffusivity; subgrid model ID DYNAMICAL MODEL; INERTIAL-RANGE; TURBULENCE; SIMULATION; KOLMOGOROV AB The standard Smagorinsky subgrid scale model for large eddy simulation can be derived from turbulent eddy viscosity models by assuming that the unresolved scales exhibit a Kolmogorov energy spectrum. The present work provides a general framework for developing eddy viscosity and corresponding subgrid models for flow problems in which Kolmogorov scaling cannot be assumed because additional physical mechanisms strongly modify the turbulence dynamics. Examples of such mechanisms include externally imposed time scales, compressibility, and intermittency. The general formalism is also applied to the turbulent thermal diffusivity. In special cases, this approach yields models that agree with those existing in the literature. (c) 2005 Elsevier B.V. All rights reserved. C1 NASA, Langley Res Ctr, Computat Modeling & Simulat Branch, Hampton, VA 23681 USA. CNRS, UMR 5008, Ctr Therm Lyon, F-69621 Villeurbanne, France. Florida State Univ, Tallahassee, FL 32306 USA. RP Rubinstein, R (reprint author), NASA, Langley Res Ctr, Computat Modeling & Simulat Branch, Hampton, VA 23681 USA. EM r.rubinstein@larc.nasa.gov NR 27 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9601 J9 PHYS LETT A JI Phys. Lett. A PD OCT 10 PY 2005 VL 346 IS 1-3 BP 168 EP 173 DI 10.1016/j.physleta.2005.07.074 PG 6 WC Physics, Multidisciplinary SC Physics GA 968NJ UT WOS:000232168900025 ER PT J AU Schorghofer, N AF Schorghofer, N TI A physical mechanism for long-term survival of ground ice in Beacon Valley, Antarctica SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID MIOCENE GLACIER ICE; MCMURDO DRY VALLEYS; STABILITY; MARS; SUBLIMATION; SHEET; TILL; SOIL AB Radiometric dating, geomorphology, biostratigraphy, and diffusion physics provide conflicting evidence for the age of the ground ice found in Beacon Valley, Antarctica. The rate of vapor diffusion into a dry atmosphere is incompatible with aminimum radiometric age of 8 Ma. Recent measurements of meteorological conditions in Beacon Valley show that the humidity of the atmosphere, although small, is comparable to the saturation vapor pressure at the ice. Analogous conditions explain the survival of ground ice at the high latitudes of Mars. At the study site, atmospheric vapor slows the sublimation loss by a factor of three and the retreat will cease entirely if temperatures are lower by 5 degrees C. Detailed model simulations show that advection, including the advection from changes in surface pressure caused by winds, has a negligible effect on sublimation loss. C1 Univ Hawaii Manoa, NASA Astrobiol Inst, Honolulu, HI 96822 USA. RP Schorghofer, N (reprint author), Univ Hawaii, Inst Astron, 2680 Woodlawn Dr, Honolulu, HI 96822 USA. EM norb1@ifa.hawaii.edu RI Schorghofer, Norbert/A-1194-2007 NR 19 TC 22 Z9 22 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 OCT 7 PY 2005 VL 32 IS 19 AR L19503 DI 10.1029/2005GL023881 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 973WC UT WOS:000232552300003 ER PT J AU Farrell, WM Kurth, WS Kaiser, ML Desch, MD Gurnett, DA Canu, P AF Farrell, WM Kurth, WS Kaiser, ML Desch, MD Gurnett, DA Canu, P TI Narrowband Z-mode emissions interior to Saturn's plasma torus SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID SPACELAB-2 ELECTRON-BEAM; ELECTROMAGNETIC EMISSIONS; NONTHERMAL CONTINUUM; RADIATION; RADIO; MAGNETOSPHERE AB [1] During Cassini's close approach to Saturn, on 1 July 2004, a set of narrow bandwidth plasma emissions were detected by the Radio and Plasma Wave Science (RPWS) instrument in the inner magnetosphere. These discrete tones were detected between 3 and 70 kHz, with individual tone bandwidths as low as a few hundred Hertz. The tones persisted for long times ( similar to 1 hour) as Cassini flew in planetocentric radial distances of less than 2.5 R-s. During this time at lower radial distances, the spacecraft passed inside the inner edge of a clear and distinct plasma torus; this torus is located between 2.2 and similar to 10 R-s. We describe the emissions, and demonstrate that the mode of propagation is the Z-mode. The emissions are found to originate at locations where electron plasma oscillations along the plasma torus edge are relatively intense. We describe a mechanism for f(p) electrostatic-to-electromagnetic wave conversion to explain the origin of the narrowband Z-mode tones. The tones allow remote-sensing of the plasma torus and indicate that the torus is dynamic, with changes in density in the tens of percent over the course of an hour. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA. IPSL, CETP, F-78140 Velizy Villacoublay, France. RP Farrell, WM (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM william.farrell@gsfc.nasa.gov RI Farrell, William/I-4865-2013; OI Kurth, William/0000-0002-5471-6202 NR 17 TC 10 Z9 10 U1 0 U2 0 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 OCT 7 PY 2005 VL 110 IS A10 AR A10204 DI 10.1029/2005JA011102 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 975IK UT WOS:000232654000001 ER PT J AU Barnes, JW Brown, RH Turtle, EP McEwen, AS Lorenz, RD Janssen, M Schaller, EL Brown, ME Buratti, BJ Sotin, C Griffith, C Clark, R Perry, J Fussner, S Barbara, J West, R Elachi, C Bouchez, AH Roe, HG Baines, KH Bellucci, G Bibring, JP Capaccioni, F Cerroni, P Combes, M Coradini, A Cruikshank, DP Drossart, P Formisano, V Jaumann, R Langevin, Y Matson, DL McCord, TB Nicholson, PD Sicardy, B AF Barnes, JW Brown, RH Turtle, EP McEwen, AS Lorenz, RD Janssen, M Schaller, EL Brown, ME Buratti, BJ Sotin, C Griffith, C Clark, R Perry, J Fussner, S Barbara, J West, R Elachi, C Bouchez, AH Roe, HG Baines, KH Bellucci, G Bibring, JP Capaccioni, F Cerroni, P Combes, M Coradini, A Cruikshank, DP Drossart, P Formisano, V Jaumann, R Langevin, Y Matson, DL McCord, TB Nicholson, PD Sicardy, B TI A 5-micron-bright spot on Titan: Evidence for surface diversity SO SCIENCE LA English DT Article ID CASSINI RADAR AB Observations from the Cassini Visual and Infrared Mapping Spectrometer show an anomalously bright spot on Titan located at 80 degrees W and 20 degrees S. This area is bright in reflected tight at all. observed wavelengths, but is most noticeable at 5 microns. The spot is associated with a surface albedo feature identified in images taken by the Cassini Imaging Science Subsystem. We discuss various hypotheses about the source of the spot, reaching the conclusion that the spot is probably due to variation in surface composition, perhaps associated with recent geophysical phenomena. C1 Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. CALTECH, Pasadena, CA 91125 USA. Univ Nantes, CNRS, UMR 6112, Lab Planetol & Geodynam, F-44035 Nantes, France. US Geol Survey, Flagstaff, AZ 86001 USA. NASA, Goddard Inst Space Studies, New York, NY 10025 USA. WM Keck Observ, Kamuela, HI 96743 USA. CNR, Ist Fis Spazio Interplanetario, I-00133 Rome, Italy. Univ Paris 11, Inst Astrophys Spatiale, F-91405 Orsay, France. CNR, Ist Astrofis Spaziale & Fis Cosm, Rome, Italy. Observ Paris, Meudon, France. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. German Aerosp Ctr, Inst Planetary Explorat, D-12489 Berlin, Germany. Univ Washington, Dept Earth & Space Sci, Seattle, WA 98195 USA. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. RP Barnes, JW (reprint author), Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. EM jbarnes@lpl.arizona.edu RI Barnes, Jason/B-1284-2009; Turtle, Elizabeth/K-8673-2012; Lorenz, Ralph/B-8759-2016; OI Barnes, Jason/0000-0002-7755-3530; Turtle, Elizabeth/0000-0003-1423-5751; Lorenz, Ralph/0000-0001-8528-4644; Capaccioni, Fabrizio/0000-0003-1631-4314 NR 14 TC 58 Z9 59 U1 0 U2 5 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 OCT 7 PY 2005 VL 310 IS 5745 BP 92 EP 95 DI 10.1126/science.1117075 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 972TV UT WOS:000232477000044 PM 16210535 ER PT J AU Su, H Neelin, JD AF Su, H Neelin, JD TI Dynamical mechanisms for African monsoon changes during the mid-Holocene SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID MODELING INTERCOMPARISON PROJECT; TROPICAL CIRCULATION MODEL; LAKE STATUS DATA; 6000 YEARS BP; 6 KYR BP; NORTHERN AFRICA; MIDDLE HOLOCENE; CLIMATE SENSITIVITY; GCM SIMULATION; VEGETATION AB [1] During the mid-Holocene, about 6 ka BP, the African monsoon was stronger and extended farther north than in present-day climate associated with differences in orbital parameters affecting insolation. Earlier research suggests that land surface vegetation interaction and atmosphere-ocean coupling may be important to the northward extension of the Holocene monsoon rainfall, but different climate models produce different results in terms of rainfall distribution. This study examines the dynamical mechanisms that modulate the orbital forcing effect on the African monsoon convection. A series of simulations with 6 ka BP orbital parameters, modified land surface albedo that mimics grassland extending over North Africa, and alterations of the model dynamics are used. It is found that the "ventilation mechanism'' ( inflow of low moist static energy air from oceanic or poleward regions) is a key process in setting the northern rainfall boundary for the African monsoon. In particular, advection and diffusion of less moist air oppose the increase of moisture that would be required to meet the increased convective instability criteria set by the warmer tropospheric air above the continent. While changes in heat fluxes into the atmospheric column favor convection in principle, the ventilation mechanism limits the poleward extent of the region that can actually convect. C1 Univ Calif Los Angeles, Dept Atmospher & Ocean Sci, Inst Geophys & Planetary Phys, Los Angeles, CA 90095 USA. RP Su, H (reprint author), CALTECH, Jet Prop Lab, Skillstorm Govt Serv, M-S 183-701,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM neelin@atmos.ucla.edu RI Neelin, J. David/H-4337-2011 NR 46 TC 16 Z9 16 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 OCT 6 PY 2005 VL 110 IS D19 AR D19105 DI 10.1029/2005JD005806 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 973WO UT WOS:000232553500002 ER PT J AU Aguilar-Rodriguez, E Gopalswamy, N MacDowall, R Yashiro, S Kaiser, ML AF Aguilar-Rodriguez, E Gopalswamy, N MacDowall, R Yashiro, S Kaiser, ML TI A universal characteristic of type II radio bursts SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID CORONAL MASS EJECTIONS; INTERPLANETARY SHOCKS; EMISSION; SPACECRAFT; CATALOG; EVENTS; WAVES AB [1] We present a study on the spectral properties of interplanetary type II radio bursts observed by the Radio and Plasma Wave ( WAVES) experiment on board the Wind spacecraft. We investigated the relative bandwidth of the type II radio bursts observed by WAVES from 1997 up to 2003. We obtained three sets of events, based on the frequency domain of occurrence: 109 events in the low-frequency domain ( 30 KHz to 1000 kHz, detected by the RAD1 receiver), 216 events in the high-frequency domain ( 1 - 14 MHz, observed by the RAD2 receiver), and 73 events that spanned both domains ( RAD1 and RAD2). Statistical results show that the average bandwidth-to-frequency ratio (BFR) was 0.28 +/- 0.15, 0.26 +/- 0.16, and 0.32 +/- 0.15 for RAD1, RAD2, and RAD1 + RAD2, respectively. We compared our results with those obtained for ISEE-3 type II bursts and found a difference in the average BFR, which seems to be due to a selection effect. The BFR of the WAVES type II bursts is similar to that of metric type II bursts reported in published works. This suggests that the BFR is a universal characteristic, irrespective of the spectral domain. Finally, we also studied the BFR evolution with heliocentric distance using white-light observation of the associated coronal mass ejections. We found that the BFR remains roughly constant in the SOHO/LASCO field of view (i.e., from 2.1 to 32 solar radii), while the bandwidth itself decreases. C1 NASA, Extraterr Phys Lab, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Catholic Univ Amer, Dept Phys, Washington, DC 20064 USA. Univ Nacl Autonoma Mexico, Inst Geofis, Mexico City 04510, DF, Mexico. RP Aguilar-Rodriguez, E (reprint author), NASA, Extraterr Phys Lab, Goddard Space Flight Ctr, Code 695-0, Greenbelt, MD 20771 USA. EM ernesto@ssedmail.gsfc.nasa.gov RI MacDowall, Robert/D-2773-2012; Gopalswamy, Nat/D-3659-2012 NR 20 TC 5 Z9 5 U1 0 U2 0 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 OCT 6 PY 2005 VL 110 IS A12 AR A12S08 DI 10.1029/2005JA011171 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 975IN UT WOS:000232654300001 ER PT J AU Hasanyan, D Librescu, L Qin, ZM Ambur, DR AF Hasanyan, D Librescu, L Qin, ZM Ambur, DR TI Magneto-thermo-elastokinetics of geometrically nonlinear laminated composite plates. Part 1: foundation of the theory SO JOURNAL OF SOUND AND VIBRATION LA English DT Article ID MAGNETOTHERMOELASTICITY; FIELD AB A fully coupled magneto-thermo-elastokinetic model of laminated composite, finitely electroconductive plates incorporating geometrical nonlinearities and subjected to a combination of magnetic and thermal fields, as well as carrying an electrical current is developed. In this context, the first-order transversely shearable plate theory in conjunction with von-Karman geometrically nonlinear strain concept is adopted. Related to the distribution of electric and magnetic field disturbances within the plate, the assumptions proposed by Ambartsumyan and his collaborators are adopted. Based on the electromagnetic equations (i.e. the ones by Faraday, Amp re, Ohm, Maxwell and Lorentz), the modified Fourier's law of heat conduction and on the elastokinetic field equations, the 3-D coupled problem is reduced to an equivalent 2-D one. The theory developed herein provides a foundation for the investigation, both analytical and numerical, of the interacting effects among the magnetic, thermal and elastic fields in multi-layered thin plates made of anisotropic materials. (c) 2004 Elsevier Ltd. All rights reserved. C1 Virginia Polytech Inst & State Univ, Dept Engn Sci & Mech, Blacksburg, VA 24061 USA. NASA, Glenn Res Ctr, Struct Div, Cleveland, OH 44135 USA. RP Librescu, L (reprint author), Virginia Polytech Inst & State Univ, Dept Engn Sci & Mech, Blacksburg, VA 24061 USA. EM librescu@vt.edu NR 22 TC 7 Z9 7 U1 1 U2 1 PU ACADEMIC PRESS LTD ELSEVIER SCIENCE LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-460X J9 J SOUND VIB JI J. Sound Vibr. PD OCT 6 PY 2005 VL 287 IS 1-2 BP 153 EP 175 DI 10.1016/j.jsv.2004.10.050 PG 23 WC Acoustics; Engineering, Mechanical; Mechanics SC Acoustics; Engineering; Mechanics GA 956TY UT WOS:000231323900008 ER PT J AU Qin, ZM Hasanyan, D Librescu, L Ambur, DR AF Qin, ZM Hasanyan, D Librescu, L Ambur, DR TI Magneto-thermo-elastokinetics of geometrically nonlinear laminated composite plates. Part 2: vibration and wave propagation SO JOURNAL OF SOUND AND VIBRATION LA English DT Article ID SHEAR AB In Part 1 of this paper, the governing equations of geometrically nonlinear, anisotropic composite plates incorporating magneto-thermo-elastic effects have been derived. In order to gain insight into the implications of a number of geometrical and physical features of the system, three special cases are investigated: (i) free vibration of a plate strip immersed in a transversal magnetic field; (ii) free vibration of the plate strip immersed in an axial magnetic field; (iii) magneto-elastic wave propagations of an infinite plate. Within each of these cases, a prescribed uniform thermal field is considered. Special coupling characteristics between the magnetic and elastic fields are put into evidence. Extensive numerical investigations are conducted and pertinent conclusions which highlight the various effects induced by the magneto-elastic couplings and the finite electroconductivity, are outlined. (c) 2004 Elsevier Ltd. All rights reserved. C1 Virginia Polytech Inst & State Univ, Dept Engn Sci & Mech, Blacksburg, VA 24061 USA. NASA, Glenn Res Ctr, Struct Div, Cleveland, OH 44135 USA. RP Librescu, L (reprint author), Virginia Polytech Inst & State Univ, Dept Engn Sci & Mech, Mail Code 0219,219 Norris Hall, Blacksburg, VA 24061 USA. EM librescu@vt.edu NR 8 TC 7 Z9 7 U1 0 U2 1 PU ACADEMIC PRESS LTD ELSEVIER SCIENCE LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-460X J9 J SOUND VIB JI J. Sound Vibr. PD OCT 6 PY 2005 VL 287 IS 1-2 BP 177 EP 201 DI 10.1016/j.jsv.2004.10.053 PG 25 WC Acoustics; Engineering, Mechanical; Mechanics SC Acoustics; Engineering; Mechanics GA 956TY UT WOS:000231323900009 ER PT J AU Des Marais, DJ AF Des Marais, DJ TI Palaeobiology - Sea change in sediments SO NATURE LA English DT Editorial Material ID PROTEROZOIC OCEAN CHEMISTRY; EVOLUTION C1 NASA, Exobiol Branch, Ames Res Ctr, Moffett Field, CA 94035 USA. NASA, Astrobiol Inst, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Des Marais, DJ (reprint author), NASA, Exobiol Branch, Ames Res Ctr, MS 239-4, Moffett Field, CA 94035 USA. EM david.j.desmarais@nasa.gov NR 9 TC 2 Z9 2 U1 1 U2 3 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD OCT 6 PY 2005 VL 437 IS 7060 BP 826 EP 827 DI 10.1038/437826b PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 970VB UT WOS:000232338600031 PM 16208356 ER PT J AU Gehrels, N Sarazin, CL O'Brien, PT Zhang, B Barbier, L Barthelmy, SD Blustin, A Burrows, DN Cannizzo, J Cummings, JR Goad, M Holland, ST Hurkett, CP Kennea, JA Levan, A Markwardt, CB Mason, KO Meszaros, P Page, M Palmer, DM Rol, E Sakamoto, T Willingale, R Angelini, L Beardmore, A Boyd, PT Breeveld, A Campana, S Chester, MM Chincarini, G Cominsky, LR Cusumano, G de Pasquale, M Fenimore, EE Giommi, P Gronwall, C Grupe, D Hill, JE Hinshaw, D Hjorth, J Hullinger, D Hurley, KC Klose, S Kobayashi, S Kouveliotou, C Krimm, HA Mangano, V Marshall, FE McGowan, K Moretti, A Mushotzky, RF Nakazawa, K Norris, JP Nousek, JA Osborne, JP Page, K Parsons, AM Patel, S Perri, M Poole, T Romano, P Roming, PWA Rosen, S Sato, G Schady, P Smale, AP Sollerman, J Starling, R Still, M Suzuki, M Tagliaferri, G Takahashi, T Tashiro, M Tueller, J Wells, AA White, NE Wijers, RAMJ AF Gehrels, N Sarazin, CL O'Brien, PT Zhang, B Barbier, L Barthelmy, SD Blustin, A Burrows, DN Cannizzo, J Cummings, JR Goad, M Holland, ST Hurkett, CP Kennea, JA Levan, A Markwardt, CB Mason, KO Meszaros, P Page, M Palmer, DM Rol, E Sakamoto, T Willingale, R Angelini, L Beardmore, A Boyd, PT Breeveld, A Campana, S Chester, MM Chincarini, G Cominsky, LR Cusumano, G de Pasquale, M Fenimore, EE Giommi, P Gronwall, C Grupe, D Hill, JE Hinshaw, D Hjorth, J Hullinger, D Hurley, KC Klose, S Kobayashi, S Kouveliotou, C Krimm, HA Mangano, V Marshall, FE McGowan, K Moretti, A Mushotzky, RF Nakazawa, K Norris, JP Nousek, JA Osborne, JP Page, K Parsons, AM Patel, S Perri, M Poole, T Romano, P Roming, PWA Rosen, S Sato, G Schady, P Smale, AP Sollerman, J Starling, R Still, M Suzuki, M Tagliaferri, G Takahashi, T Tashiro, M Tueller, J Wells, AA White, NE Wijers, RAMJ TI A short gamma-ray burst apparently associated with an elliptical galaxy at redshift z=0.225 SO NATURE LA English DT Article ID SHORT-DURATION; NEUTRON-STARS; AFTERGLOWS; SGR-1806-20; BINARIES; FLARE AB Gamma-ray bursts (GRBs) come in two classes(1): long (> 2 s), soft-spectrum bursts and short, hard events. Most progress has been made on understanding the long GRBs, which are typically observed at high redshift ( z approximate to 1) and found in subluminous star-forming host galaxies. They are likely to be produced in core-collapse explosions of massive stars(2). In contrast, no short GRB had been accurately (< 1000) and rapidly ( minutes) located. Here we report the detection of the X-ray afterglow from - and the localization of - the short burst GRB 050509B. Its position on the sky is near a luminous, non-star-forming elliptical galaxy at a redshift of 0.225, which is the location one would expect(3,4) if the origin of this GRB is through the merger of neutron-star or blackhole binaries. The X-ray afterglow was weak and faded below the detection limit within a few hours; no optical afterglow was detected to stringent limits, explaining the past difficulty in localizing short GRBs. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Virginia, Dept Astron, Charlottesville, VA 22903 USA. Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. Univ Nevada, Dept Phys, Las Vegas, NV 89154 USA. UCL, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England. Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. Univ Maryland Baltimore Cty, Joint Ctr Astrophys, Baltimore, MD 21250 USA. CNR, Washington, DC 20418 USA. Univ Space Res Assoc, Columbia, MD 21044 USA. Univ Maryland, Dept Astron, College Pk, MD 20742 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. INAF, Osservatorio Astron Brera, I-23807 Merate, Italy. Univ Milano Bicocca, I-20126 Milan, Italy. Sonoma State Univ, Dept Phys & Astron, Rohnert Pk, CA 94928 USA. INAF, Ist Astrofis Spaziale & Cosm, I-90146 Palermo, Italy. ASI Sci Data Ctr, I-00044 Frascati, Italy. SP Syst Inc, Greenbelt, MD 20770 USA. Univ Copenhagen, Niels Bohr Inst, DK-2100 Copenhagen, Denmark. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Thuringer Landessternwarte Tautenburg, D-07778 Tautenburg, Germany. NASA, George C Marshall Space Flight Ctr, NSSTC, Huntsville, AL 35805 USA. JAXA, Inst Space & Astronaut Sci, Kanagawa 2298510, Japan. Univ Space Res Assoc, NSSTC, Huntsville, AL 35805 USA. NASA Headquarters, Off Space Sci, Washington, DC 20546 USA. Stockholm Observ, Dept Astron, S-10691 Stockholm, Sweden. Univ Amsterdam, Astron Inst Anton Pannekoek, NL-1098 SJ Amsterdam, Netherlands. Saitama Univ, Dept Phys, Sakura, Saitama 3388570, Japan. RP Gehrels, N (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM gehrels@milkyway.gsfc.nasa.gov RI White, Nicholas/B-6428-2012; Boyd, Patricia/D-3274-2012; Gehrels, Neil/D-2971-2012; Tueller, Jack/D-5334-2012; Barthelmy, Scott/D-2943-2012; Parsons, Ann/I-6604-2012; Tashiro, Makoto/J-4562-2012; Hjorth, Jens/M-5787-2014; OI White, Nicholas/0000-0003-3853-3462; Hjorth, Jens/0000-0002-4571-2306; Campana, Sergio/0000-0001-6278-1576; giommi, paolo/0000-0002-2265-5003; Wijers, Ralph/0000-0002-3101-1808; Cusumano, Giancarlo/0000-0002-8151-1990; moretti, alberto/0000-0002-9770-0315 NR 30 TC 379 Z9 385 U1 0 U2 8 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD OCT 6 PY 2005 VL 437 IS 7060 BP 851 EP 854 DI 10.1038/nature04142 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 970VB UT WOS:000232338600038 PM 16208363 ER PT J AU Villasenor, JS Lamb, DQ Ricker, GR Atteia, JL Kawai, N Butler, N Nakagawa, Y Jernigan, JG Boer, M Crew, GB Donaghy, TQ Doty, J Fenimore, EE Galassi, M Graziani, C Hurley, K Levine, A Martel, F Matsuoka, M Olive, JF Prigozhin, G Sakamoto, T Shirasaki, Y Suzuki, M Tamagawa, T Vanderspek, R Woosley, SE Yoshida, A Braga, J Manchanda, R Pizzichini, G Takagishi, K Yamauchi, M AF Villasenor, JS Lamb, DQ Ricker, GR Atteia, JL Kawai, N Butler, N Nakagawa, Y Jernigan, JG Boer, M Crew, GB Donaghy, TQ Doty, J Fenimore, EE Galassi, M Graziani, C Hurley, K Levine, A Martel, F Matsuoka, M Olive, JF Prigozhin, G Sakamoto, T Shirasaki, Y Suzuki, M Tamagawa, T Vanderspek, R Woosley, SE Yoshida, A Braga, J Manchanda, R Pizzichini, G Takagishi, K Yamauchi, M TI Discovery of the short gamma-ray burst GRB 050709 SO NATURE LA English DT Article ID 28 FEBRUARY 1997; SGR-1806-20; AFTERGLOW; SPECTRA; CATALOG; FLARE AB Gamma-ray bursts (GRBs) fall into two classes: short-hard and long-soft bursts(1-3). The latter are now known to have X-ray(4) and optical(5) afterglows, to occur at cosmological distances(6) in star-forming galaxies(7), and to be associated with the explosion of massive stars(8,9). In contrast, the distance scale, the energy scale and the progenitors of the short bursts have remained a mystery. Here we report the discovery of a short-hard burst whose accurate localization has led to follow-up observations that have identified the X-ray afterglow(10) and ( for the first time) the optical afterglow(10,11) of a short-hard burst; this in turn led to the identification of the host galaxy of the burst as a late-type galaxy at z = 0.16 (ref. 10). These results show that at least some short-hard bursts occur at cosmological distances in the outskirts of galaxies, and are likely to be caused by the merging of compact binaries. C1 MIT, Kavli Inst, Cambridge, MA 02139 USA. Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. Observ Midi Pyrenees, Astrophys Lab, F-31400 Toulouse, France. Tokyo Inst Technol, Dept Phys, Meguro Ku, Tokyo 1528551, Japan. Aoyama Gakuin Univ, Dept Math & Phys, Kanagawa 2298558, Japan. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Observ Midi Pyrenees, Ctr Etud Spatiale Rayonnements, F-31028 Toulouse, France. Noqsi Aerosp Ltd, Pine, CO 80470 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Espace Inc, Hull, MA 02045 USA. Japan Aerosp Explorat Agcy, Tsukuba Space Ctr, Tsukuba, Ibaraki 3058505, Japan. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Natl Astron Observ, Tokyo 1818588, Japan. RIKEN, Wako, Saitama 3510198, Japan. Univ Calif Santa Cruz, Dept Astron & Astrophys, Santa Cruz, CA 95064 USA. Inst Nacl Pesquisas Espaciais, BR-12227010 Sao Jose Dos Campos, Brazil. Tata Inst Fundamental Res, Dept Astron & Astrophys, Bombay 400005, Maharashtra, India. INAF IASF Bologna, I-40129 Bologna, Italy. Miyazaki Univ, Fac Engn, Miyazaki 8892192, Japan. RP Ricker, GR (reprint author), MIT, Kavli Inst, 70 Vassar St, Cambridge, MA 02139 USA. EM jsvilla@space.mit.edu; grr@space.mit.edu NR 28 TC 187 Z9 189 U1 0 U2 2 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD OCT 6 PY 2005 VL 437 IS 7060 BP 855 EP 858 DI 10.1038/nature04213 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 970VB UT WOS:000232338600039 PM 16208364 ER PT J AU Hjorth, J Watson, D Fynbo, JPU Price, PA Jensen, BL Jorgensen, UG Kubas, D Gorosabel, J Jakobsson, P Sollerman, J Pedersen, K Kouveliotou, C AF Hjorth, J Watson, D Fynbo, JPU Price, PA Jensen, BL Jorgensen, UG Kubas, D Gorosabel, J Jakobsson, P Sollerman, J Pedersen, K Kouveliotou, C TI The optical afterglow of the short gamma-ray burst GRB 050709 SO NATURE LA English DT Article ID 28 FEBRUARY 1997; HOST GALAXIES; ERROR BOX; SUPERNOVA; PROGENITORS; CONSTRAINTS; DISCOVERY; PROSPECTS; SPECTRA; MODEL AB It has long been known that there are two classes(1) of gamma-ray bursts (GRBs), mainly distinguished by their durations. The breakthrough in our understanding of long-duration GRBs ( those lasting more than similar to 2 s), which ultimately linked them with energetic type Ic supernovae(2-4), came from the discovery of their long-lived X-ray(5) and optical(6,7) 'afterglows', when precise and rapid localizations of the sources could finally be obtained. X-ray localizations have recently become available(8,9) for short ( duration < 2 s) GRBs, which have evaded optical detection for more than 30 years. Here we report the first discovery of transient optical emission (R-band magnitude similar to 23) associated with a short burst: GRB 050709. The optical afterglow was localized with subarcsecond accuracy, and lies in the outskirts of a blue dwarf galaxy. The optical and X-ray(10) afterglow properties 34 h after the GRB are reminiscent of the afterglows of long GRBs, which are attributable to synchrotron emission from ultrarelativistic ejecta. We did not, however, detect a supernova, as found in most nearby long GRB afterglows, which suggests a different origin for the short GRBs. C1 Univ Copenhagen, Niels Bohr Inst, Dark Cosmol Ctr, DK-2100 Copenhagen, Denmark. Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA. European So Observ, Santiago 19, Chile. CSIC, Inst Astrofis Andalucia, E-18080 Granada, Spain. Stockholm Univ, Dept Astron, S-10691 Stockholm, Sweden. NASA, George C Marshall Space Flight Ctr, Natl Space Sci Technol Ctr, Huntsville, AL 35805 USA. RP Hjorth, J (reprint author), Univ Copenhagen, Niels Bohr Inst, Dark Cosmol Ctr, Juliane Maries Vej, DK-2100 Copenhagen, Denmark. EM jens@astro.ku.dk RI Fynbo, Johan/L-8496-2014; Hjorth, Jens/M-5787-2014; Watson, Darach/E-4521-2015; Jensen, Brian Lindgren/E-1275-2015; Jakobsson, Pall/L-9950-2015 OI Fynbo, Johan/0000-0002-8149-8298; Hjorth, Jens/0000-0002-4571-2306; Watson, Darach/0000-0002-4465-8264; Jensen, Brian Lindgren/0000-0002-0906-9771; Jakobsson, Pall/0000-0002-9404-5650 NR 26 TC 206 Z9 207 U1 0 U2 1 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD OCT 6 PY 2005 VL 437 IS 7060 BP 859 EP 861 DI 10.1038/nature04174 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 970VB UT WOS:000232338600040 PM 16208365 ER PT J AU Luthcke, SB Rowlands, DD Williams, TA Sirota, M AF Luthcke, SB Rowlands, DD Williams, TA Sirota, M TI Reduction of ICESat systematic geolocation errors and the impact on ice sheet elevation change detection SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID CALIBRATION; RANGE AB The Ice Cloud and land Elevation Satellite ( ICESat) has been acquiring unprecedented observations of our planet's varied surfaces with impressive precision. However, systematic errors remain in the data including orbital variation and long-term bias trend pointing errors. These errors are particularly troublesome because they cannot be separated from true surface elevation change and confound instrument range bias determination. We present a method to correct these systematic pointing errors to the sub-arcsecond level. We demonstrate the impact of these errors and their corrections on Greenland and Antarctica ice sheet surface elevation change observations and sea surface anomaly observations, as well as instrument range bias determination. While further improvements in the ICESat data will certainly be made, the analysis presented here demonstrates a major error source can be significantly reduced, resulting in improved surface elevation accuracies for ice sheet elevation change detection. C1 NASA, Space Geodesy Lab, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. SGT Inc, Div Sci, Greenbelt, MD 20770 USA. Sigma Space Corp, Lanham, MD 20706 USA. RP Luthcke, SB (reprint author), NASA, Space Geodesy Lab, Goddard Space Flight Ctr, Code 697, Greenbelt, MD 20771 USA. EM scott.b.luthcke@nasa.gov RI Rowlands, David/D-2751-2012; Luthcke, Scott/D-6283-2012 NR 5 TC 39 Z9 40 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 OCT 5 PY 2005 VL 32 IS 21 AR L21S05 DI 10.1029/2005GL023689 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 973WF UT WOS:000232552600001 ER PT J AU Sauber, J Molnia, B Carabajal, C Luthcke, S Muskett, R AF Sauber, J Molnia, B Carabajal, C Luthcke, S Muskett, R TI Ice elevations and surface change on the Malaspina Glacier, Alaska SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article AB Here we use Ice, Cloud and land Elevation Satellite (ICESat)-derived elevations and surface characteristics to investigate the Malaspina Glacier of southern Alaska. Although there is significant elevation variability between ICESat tracks on this glacier, we were able to discern general patterns in surface elevation change by using a regional digital elevation model (DEM) as a reference surface. Specifically, we report elevation differences between ICESat Laser 1 - 3 observations ( February 2003 November 2004) and a Shuttle Radar Topography Mission (SRTM)-derived DEM from February 2000. Elevation decreases of up to 20 - 25 m over a 3 - 4 year time period were observed across the folded loop moraine on the southern portion of the Malaspina Glacier. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. US Geol Survey, Natl Ctr 926A, Reston, VA USA. Univ Alaska Fairbanks, Int Arctic Res Ctr, Fairbanks, AK 99775 USA. RP Sauber, J (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM jeanne.m.sauber-rosenberg@nasa.gov RI Luthcke, Scott/D-6283-2012; Sauber, Jeanne/D-7684-2012 NR 12 TC 23 Z9 23 U1 1 U2 6 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 OCT 5 PY 2005 VL 32 IS 23 AR L23S01 DI 10.1029/2005GL023943 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 973WH UT WOS:000232552800001 ER PT J AU Lamarque, JF Kiehl, JT Brasseur, GP Butler, T Cameron-Smith, P Collins, WD Collins, WJ Granier, C Hauglustaine, D Hess, PG Holland, EA Horowitz, L Lawrence, MG McKenna, D Merilees, P Prather, MJ Rasch, PJ Rotman, D Shindell, D Thornton, P AF Lamarque, JF Kiehl, JT Brasseur, GP Butler, T Cameron-Smith, P Collins, WD Collins, WJ Granier, C Hauglustaine, D Hess, PG Holland, EA Horowitz, L Lawrence, MG McKenna, D Merilees, P Prather, MJ Rasch, PJ Rotman, D Shindell, D Thornton, P TI Assessing future nitrogen deposition and carbon cycle feedback using a multimodel approach: Analysis of nitrogen deposition SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID GENERAL-CIRCULATION MODEL; CHEMICAL-TRANSPORT MODELS; GASEOUS DRY DEPOSITION; TROPOSPHERIC OZONE; CLIMATE MODEL; 3-DIMENSIONAL SIMULATION; NONMETHANE HYDROCARBONS; TERRESTRIAL ECOSYSTEMS; SURFACE RESISTANCES; ASSIMILATED WINDS AB [1] In this study, we present the results of nitrogen deposition on land from a set of 29 simulations from six different tropospheric chemistry models pertaining to present-day and 2100 conditions. Nitrogen deposition refers here to the deposition ( wet and dry) of all nitrogen-containing gas phase chemical species resulting from NOx (NO + NO2) emissions. We show that under the assumed IPCC SRES A2 scenario the global annual average nitrogen deposition over land is expected to increase by a factor of similar to 2.5, mostly because of the increase in nitrogen emissions. This will significantly expand the areas with annual average deposition exceeding 1 gN/m(2)/year. Using the results from all models, we have documented the strong linear relationship between models on the fraction of the nitrogen emissions that is deposited, regardless of the emissions ( present day or 2100). On average, approximately 70% of the emitted nitrogen is deposited over the landmasses. For present-day conditions the results from this study suggest that the deposition over land ranges between 25 and 40 Tg(N)/year. By 2100, under the A2 scenario, the deposition over the continents is expected to range between 60 and 100 Tg( N)/year. Over forests the deposition is expected to increase from 10 Tg( N)/year to 20 Tg( N)/year. In 2100 the nitrogen deposition changes from changes in the climate account for much less than the changes from increased nitrogen emissions. C1 Natl Ctr Atmospher Res, Boulder, CO 80305 USA. Max Planck Inst Meteorol, D-20146 Hamburg, Germany. Max Planck Inst Chem, D-55128 Mainz, Germany. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Met Off, Hadley Ctr, Exeter EX1 3PB, Devon, England. Inst Pierre Simon Laplace, Serv Aeron, Paris, France. NOAA, CIRES, Aeron Lab, Boulder, CO USA. Inst Pierre Simon Laplace, Lab Sci Climat & Environm, F-91191 Gif Sur Yvette, France. NOAA, Geophys Fluid Dynam Lab, Princeton, NJ 08542 USA. Univ Calif Irvine, Irvine, CA 92697 USA. NASA, Goddard Inst Space Studies, New York, NY 10025 USA. RP Natl Ctr Atmospher Res, Boulder, CO 80305 USA. EM lamar@ucar.edu RI Cameron-Smith, Philip/E-2468-2011; McKenna, Daniel/E-7806-2014; Thornton, Peter/B-9145-2012; Collins, William/A-5895-2010; Butler, Tim/G-1139-2011; Shindell, Drew/D-4636-2012; Collins, William/J-3147-2014; Granier, Claire/D-5360-2013; Hess, Peter/M-3145-2015; Horowitz, Larry/D-8048-2014; Lamarque, Jean-Francois/L-2313-2014 OI Cameron-Smith, Philip/0000-0002-8802-8627; McKenna, Daniel/0000-0002-4360-4782; Thornton, Peter/0000-0002-4759-5158; Collins, William/0000-0002-7419-0850; Collins, William/0000-0002-4463-9848; Granier, Claire/0000-0001-7344-7995; Hess, Peter/0000-0003-2439-3796; Horowitz, Larry/0000-0002-5886-3314; Lamarque, Jean-Francois/0000-0002-4225-5074 NR 73 TC 102 Z9 104 U1 10 U2 22 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 OCT 5 PY 2005 VL 110 IS D19 AR D19303 DI 10.1029/2005JD005825 PG 21 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 973WN UT WOS:000232553400003 ER PT J AU Zhou, M Yu, H Dickinson, RE Dubovik, O Holben, BN AF Zhou, M Yu, H Dickinson, RE Dubovik, O Holben, BN TI A normalized description of the direct effect of key aerosol types on solar radiation as estimated from Aerosol Robotic Network aerosols and Moderate Resolution Imaging Spectroradiometer albedos SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SKY RADIANCE MEASUREMENTS; OPTICAL-PROPERTIES; TROPOSPHERIC AEROSOLS; GLOBAL DISTRIBUTIONS; MODIS RETRIEVALS; GOCART MODEL; CLIMATE; CLOUD; SATELLITE; AERONET AB [1] The interactions between aerosols and solar radiation are determined by a combination of aerosol properties (i.e., types), surface properties (i.e., albedo) and clouds. These determining factors vary for different regions. We examine how these differences contribute to the impact of aerosols on the top-of-atmosphere (TOA) and surface radiation. In this study, the AERONET ( Aerosol Robotic Network) aerosol climatology is used, in conjunction with surface albedo and cloud products from Moderate Resolution Imaging Spectroradiometer ( MODIS), to calculate the aerosol direct radiative effect (ADRE) and its normalized form (NADRE). The NADRE is defined as the ADRE normalized by optical depth at 550 nm and is mainly determined by internal aerosol optical properties and geographical parameters. These terms are evaluated for cloud-free and cloudy conditions and for all-mode and fine-mode aerosols. Single-scattering albedo is an important variable determining ADRE of biomass burning. Because of stronger absorption by the smoke over South Africa the average NADRE over South America is similar to 35% larger at the TOA but similar to 38% smaller at the surface than that over South Africa. The surface albedo is another important factor in determining ADRE, especially for mineral dust. As the surface albedo varies from similar to 0.1 to similar to 0.35, it is observed that the dust NADRE ranges from - 44 to - 17 Wm(-2) tau(-1) at the TOA and from - 80 to - 48 Wm(-2) tau(-1) at the surface over the Saharan deserts, Arabian Peninsula, and their surrounding oceans. We also find that the NADRE of fine-mode aerosol is larger at the TOA but smaller at the surface in comparison to that of all-mode aerosol because of its larger single-scattering albedo and smaller asymmetry factor. Cloudy-sky ADRE is usually not negligible for the observed cloud optical thickness, but the TOA ADRE with clouds is sensitive to the relative location of aerosols and cloud layer. C1 Georgia Inst Technol, Sch Earth & Atmospher Sci, Atlanta, GA 30332 USA. NASA, Goddard Earth Sci & Technol Ctr, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Maryland Baltimore Cty, Greenbelt, MD 20771 USA. RP Georgia Inst Technol, Sch Earth & Atmospher Sci, 311 Ferst Dr, Atlanta, GA 30332 USA. EM mzhou@eas.gatech.edu RI Yu, Hongbin/C-6485-2008; Dubovik, Oleg/A-8235-2009 OI Yu, Hongbin/0000-0003-4706-1575; Dubovik, Oleg/0000-0003-3482-6460 NR 58 TC 0 Z9 0 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 OCT 5 PY 2005 VL 110 IS D19 AR D19202 DI 10.1029/2005JD005909 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 973WN UT WOS:000232553400004 ER PT J AU Thundathil, MA Jones, CY Snyder, GJ Haile, SM AF Thundathil, MA Jones, CY Snyder, GJ Haile, SM TI Nonstoichiometry, structure, and electrical properties of "SrPrO3" SO CHEMISTRY OF MATERIALS LA English DT Article ID NEUTRON-DIFFRACTION; MAGNETIC-PROPERTIES; CRYSTAL-STRUCTURES; BARIUM CERATE; HIGH-TEMPERATURES; THIN-FILMS; BAPRO3; PEROVSKITES; PROTON; BACEO3 AB The single-phase composition with the perovskite structure type in the Sr-Pr-O system has been identified as (Sr(0.935)Pr(0.0431)square(0.022))Pr1.0O3 from neutron diffraction refinements, chemical analysis, and thermogravimetric analysis. The cation deficient oxide crystallizes in a GdFeO3-type orthorhombic structure, space group Pbnm, with lattice parameters a = 5.988 00(17), b = 6.12136(17), c = 8.548 58-(24) A, and Z = 4 at 300 K. Thermogravimetric analysis confirms that the compound is not oxygen deficient. (Sr0.935Pr0.043)Pr1.0O3 exhibits semiconducting behavior. The bulk (grain interior) conductivity at 36 degrees C is 5.2 x 10(-5) S cm-1 with an activation energy for charge transport of 0.26 eV. C1 CALTECH, Pasadena, CA 91125 USA. Natl Inst Stand & Technol, Ctr Neutron Res, Gaithersburg, MD 20899 USA. CALTECH, Jet Propuls Lab, Pasadena, CA 91109 USA. RP Haile, SM (reprint author), CALTECH, Pasadena, CA 91125 USA. EM smhaile@caltech.edu RI Snyder, G. Jeffrey/E-4453-2011; Snyder, G/I-2263-2015; Haile, Sossina/I-3448-2015 OI Snyder, G. Jeffrey/0000-0003-1414-8682; NR 34 TC 3 Z9 3 U1 0 U2 7 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 OCT 4 PY 2005 VL 17 IS 20 BP 5146 EP 5154 DI 10.1021/cm0505895k PG 9 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 970RG UT WOS:000232326700035 ER PT J AU Loughman, RP Flittner, DE Herman, BM Bhartia, PK Hilsenrath, E McPeters, RD AF Loughman, RP Flittner, DE Herman, BM Bhartia, PK Hilsenrath, E McPeters, RD TI Description and sensitivity analysis of a limb scattering ozone retrieval algorithm SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SOLAR MESOSPHERE EXPLORER; RADIATIVE-TRANSFER MODEL; MINOR SPECIES DENSITIES; SUNLIGHT MEASUREMENTS; VIEWING GEOMETRY; SPECTRAL REGION; ODIN SATELLITE; OPTICAL DEPTH; O-3 PROFILES; OSIRIS AB [1] We present the theoretical basis for an algorithm that retrieves vertical profiles of ozone concentration using measurements of light scattered from the limb of the atmosphere. Simulated radiances at wavelengths between 300 and 675 nm are inverted using the optimal estimation technique, producing a retrieved ozone number density profile between 10 and 55 km. A detailed sensitivity analysis of this ozone retrieval algorithm follows. The largest source of ozone retrieval error is tangent height misregistration (i.e., instrument pointing error), which is relevant throughout the altitude range of interest and produces retrieval errors on the order of 10 - 20% due to a tangent height registration error of 0.5 km. The retrieved profile is shifted in altitude relative to the true profile, with very little distortion of the profile shape. Sensitivity to stratospheric aerosol is also a significant source of error, with errors of 5 - 8% for altitudes less than 40 km under background aerosol conditions when an aerosol-free atmosphere is assumed by the algorithm. Using an incorrect a priori ozone estimate can produce errors up to 15% at altitudes near 10 km, but the a priori profile has little influence above that level. Addressing these error sources ( e. g., with better instrument pointing knowledge, introduction of reliable aerosol information, and better instrument signal-to-noise to reduce the importance of the a priori ozone estimate, respectively) is the key to significantly improving the retrieval accuracy. Further improvement would then be limited by several secondary error sources that produce retrieval errors at the 5% level. C1 Hampton Univ, Ctr Atmospher Sci, Hampton, VA 23668 USA. NASA, Goddard Space Flight Ctr, Atmospheres Lab, Atmospher Chem & Dynam Branch, Greenbelt, MD 20771 USA. Univ Arizona, Inst Atmospher Phys, Tucson, AZ 85721 USA. RP Loughman, RP (reprint author), Hampton Univ, Ctr Atmospher Sci, Hampton, VA 23668 USA. EM robert.loughman@hamptonu.edu 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 62 TC 15 Z9 16 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 OCT 4 PY 2005 VL 110 IS D19 AR D19301 DI 10.1029/2004JD005429 PG 23 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 973WM UT WOS:000232553300002 ER PT J AU Wang, Z Heymsfield, GM Li, LH Heymsfield, AJ AF Wang, Z Heymsfield, GM Li, LH Heymsfield, AJ TI Retrieving optically thick ice cloud microphysical properties by using airborne dual-wavelength radar measurements SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID DISCRETE DIPOLE APPROXIMATION; WATER-CONTENT; CIRRUS CLOUDS; PARTICLE-SIZE; IMAGING RADIOMETER; DOPPLER RADAR; REFLECTIVITY; PARAMETERS; EXTINCTION; CLIMATE AB [1] An algorithm to retrieve optically thick ice cloud microphysical property profiles is developed by using the GSFC 9.6 GHz ER-2 Doppler Radar (EDOP) and the 94 GHz Cloud Radar System (CRS) measurements aboard the high-altitude ER-2 aircraft. In situ size distribution and total water content data from the CRYSTAL-FACE field campaign are used for the algorithm development. To reduce uncertainty in calculated radar reflectivity factors (Z(e)) at these wavelengths, coincident radar measurements and size distribution data are used to guide the selection of mass-length relationships and to deal with the density and nonspherical effects of ice crystals on the Z(e) calculations. The algorithm is able to retrieve microphysical property profiles of optically thick ice clouds, such as deep convective and anvil clouds, which are very challenging for single-wavelength radar and lidar. Examples of retrieved microphysical properties for deep convective clouds are presented, which show that EDOP and CRS measurements provide rich information to study cloud structure and evolution. Good agreement between IWPs derived from an independent submillimeter-wave radiometer, CoSSIR, and dual-wavelength radar measurements indicates accuracy of the IWC retrieved from the dual-wavelength radar algorithm. C1 Univ Wyoming, Dept Atmospher Sci, Laramie, WY 82071 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. Natl Ctr Atmospher Res, Boulder, CO 80307 USA. RP Wang, Z (reprint author), Univ Wyoming, Dept Atmospher Sci, 1000 E Univ Ave, Laramie, WY 82071 USA. EM zwang@uwyo.edu RI Heymsfield, Andrew/E-7340-2011; Wang, Zhien/F-4857-2011 NR 39 TC 23 Z9 23 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 OCT 4 PY 2005 VL 110 IS D19 AR D19201 DI 10.1029/2005JD005969 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 973WM UT WOS:000232553300005 ER PT J AU Anderson, MS AF Anderson, MS TI Surface enhanced infrared absorption by coupling phonon and plasma resonance SO APPLIED PHYSICS LETTERS LA English DT Article ID ATOMIC-FORCE MICROSCOPE; RAMAN-SCATTERING; SPECTROSCOPY; RESOLUTION; PARTICLES AB A gold and silicon carbide particle matrix is presented that concentrates light to its surface using a combination of phonon and plasmon resonance mechanisms. The enhanced infrared absorption spectrum of absorbed molecules is used to probe the coupled phonon and plasmon surface resonances. Sensitive molecular detection is achieved by measuring the enhanced infrared absorption or the frequency shift in the surface modes of the coated matrix. This work demonstrates that hybrid polariton resonance structures using metallic and polar dielectric materials are feasible for applications in near-field microscopy, nano-optical devices, and trace chemical sensing. (C) 2005 American Institute of Physics. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Anderson, MS (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,M-S 125-109, Pasadena, CA 91109 USA. EM mark.s.anderson@jpl.nasa.gov NR 18 TC 23 Z9 24 U1 3 U2 26 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 OCT 3 PY 2005 VL 87 IS 14 AR 144102 DI 10.1063/1.2077838 PG 3 WC Physics, Applied SC Physics GA 969HR UT WOS:000232225700074 ER PT J AU Chubb, DL Wolford, DS AF Chubb, DL Wolford, DS TI Dual layer selective emitter SO APPLIED PHYSICS LETTERS LA English DT Article ID THERMAL-RADIATION; EMISSION AB A selective emitter consisting of two layers separated by a vacuum is analyzed. The bottom layer consists of a selective emitting material such as a rare earth containing crystal on a metal substrate. The top layer, which blocks long wavelength radiation, is a window such as sapphire with a deposited metal film. As a result of reduced long wavelength emission, the theoretical analysis shows that the emitter efficiency can be increased by nearly a factor of 2. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Chubb, DL (reprint author), NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. EM Donald.L.Chubb@nasa.gov NR 19 TC 3 Z9 3 U1 1 U2 8 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 OCT 3 PY 2005 VL 87 IS 14 AR 141907 DI 10.1063/1.2077853 PG 3 WC Physics, Applied SC Physics GA 969HR UT WOS:000232225700017 ER PT J AU Rupnowski, P Gentz, M Armentrout, D Sutter, JK Kumosa, M AF Rupnowski, P Gentz, M Armentrout, D Sutter, JK Kumosa, M TI The response of a woven graphite fiber/polyimide composite to aging in nitrogen SO ACTA MATERIALIA LA English DT Article DE woven graphite/polyimide composites; PMR-15; physical aging; modeling; finite element method; residual stress ID RAY-DIFFRACTION MEASUREMENTS; RESIDUAL THERMAL-STRESSES; IOSIPESCU SHEAR TESTS; ELEVATED-TEMPERATURES; +/-45-DEGREES TENSILE; ALUMINUM INCLUSIONS; ELASTIC PROPERTIES; BENDING LOADS; ROOM; DAMAGE AB The mechanical response of an eight harness satin (8HS) woven T650-35/PMR-15 composite to aging in nitrogen at 315 degrees C for up to 1000 h has been investigated both experimentally and numerically. The aging stresses in the composite were numerically predicted on a meso-scale using the concept of a unit-cell. Viscoelastic, age stiffening, and volumetric shrinkage effects were considered in the simulations to describe the mechanical behavior of the neat PMR-15 polyimide at 315 degrees C. It was found from the computations that the internal stresses in the composite increased due to aging and that the rate of the increase was not significant due to stress relaxation. The model has also shown that after 1000 h the aging stresses in the composite are much smaller than the thermal residual stresses caused by manufacturing. To verify the numerical predictions, the strength and stiffness of the composite were measured as a function of aging time using the +/- 45 degrees tensile test. The numerical predictions agreed with the experimental results, which demonstrated no meaningful influence of aging in nitrogen both on the strength and stiffness of the composite. (c) 2005 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. C1 Univ Denver, Ctr Adv Mat & Struct, Dept Engn, Denver, CO 80208 USA. NASA, Glenn Res Ctr Lewis Field, Cleveland, OH 44135 USA. RP Kumosa, M (reprint author), Univ Denver, Ctr Adv Mat & Struct, Dept Engn, 2390 S Yotk St, Denver, CO 80208 USA. EM mkumosa@du.edu RI Rupnowski, Przemyslaw/B-3520-2008; OI Rupnowski, Przemyslaw/0000-0003-0040-418X NR 36 TC 4 Z9 4 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD OCT PY 2005 VL 53 IS 17 BP 4555 EP 4565 DI 10.1016/j.actamat.2005.06.010 PG 11 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 968QP UT WOS:000232177500007 ER PT J AU Hiliuta, A Botez, RM Brenner, M AF Hiliuta, A Botez, RM Brenner, M TI Approximation of unsteady aerodynamic forces Q(k, M) by use of fuzzy techniques SO AIAA JOURNAL LA English DT Article AB The unsteady aerodynamic forces acting on an F/A-18 aircraft are calculated in the frequency domain using a doublet-lattice method (subsonic regime) or a constant-pressure method (supersonic regime). To study the effects of the control laws on a flexible fly-by-wire aircraft structure and calculate the flutter velocities and frequencies, these aerodynamic forces must be approximated in the Laplace domain. We show here that in the case where the aerodynamic forces data are calculated for a range of unevenly spaced reduced frequencies, a combination of fuzzy clustering and shape-preserving techniques can be used to obtain a very good approximation of these unsteady aerodynamic forces. Because the approximation of these forces by this new method remains actually in the frequency domain, we could easily further use for their conversion from the frequency domain into Laplace domain, classical methods such as least squares or minimum state. Finally, care must be used in the choice of reduced frequencies range, to determine the method to be deployed. C1 Ecole Technol Super, Montreal, PQ H3C 1K3, Canada. NASA, Dryden Flight Res Ctr, Edwards AFB, CA 93523 USA. RP Hiliuta, A (reprint author), Ecole Technol Super, Montreal, PQ H3C 1K3, Canada. NR 10 TC 4 Z9 4 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 OCT PY 2005 VL 43 IS 10 BP 2093 EP 2099 DI 10.2514/1.13600 PG 7 WC Engineering, Aerospace SC Engineering GA 970RZ UT WOS:000232328600002 ER PT J AU Higashitani, A Higashibata, A Sasagawa, Y Sugimoto, T Miyazawa, Y Szewcyk, NJ Viso, M Gasset, G Eche, B Fukui, K Shimazu, T Fujimoto, N Kuriyama, K Ishioka, N AF Higashitani, A Higashibata, A Sasagawa, Y Sugimoto, T Miyazawa, Y Szewcyk, NJ Viso, M Gasset, G Eche, B Fukui, K Shimazu, T Fujimoto, N Kuriyama, K Ishioka, N TI Checkpoint and physiological apoptosis in germ cells proceeds normally in spaceflown Caenorhabditis elegans SO APOPTOSIS LA English DT Article DE ced-1; C. elegans; cell corpse; checkpoint; meiosis; pachytene; spaceflight ID CHEMICALLY-DEFINED MEDIUM; DNA-DAMAGE RESPONSE; C-ELEGANS; LYMPHOCYTES JURKAT; CORPSE ENGULFMENT; P53 PROTEIN; DEATH; NEMATODE; INCREASES; GENES AB It is important for human life in space to study the effects of environmental factors during spaceflight on a number of physiological phenomena. Apoptosis plays important roles in development and tissue homeostasis in metazoans. In this study, we have analyzed apoptotic activity in germ cells of the nematode C. elegans, following spacefight. Comparison of the number of cell corpses in wild type or ced-1 mutants, grown under either ground or spaceflight conditions, showed that both pachytene-checkpoint apoptosis and physiological apoptosis in germ cells occurred normally under spaceflight conditions. In addition, the expression levels of the checkpoint and apoptosis related genes are comparable between spaceflight and ground conditions. This is the first report documenting the occurrence of checkpoint apoptosis in the space environment and suggests that metazoans, including humans, would be able to eliminate cells that have failed to repair DNA lesions introduced by cosmic radiation during spaceflight. C1 Tohoku Univ, Grad Sch Life Sci, Sendai, Miyagi 9808577, Japan. Japan Aerosp Explorat Agcy, JAXA, Tsukuba, Ibaraki 3058505, Japan. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Univ Toulouse 3, Groupement Sci Biol & Med Spatiales, F-31062 Toulouse, France. CNES, Paris 01, France. Japan Space Forum, Chiyoda Ku, Ootemachi 1000004, Japan. RP Higashitani, A (reprint author), Tohoku Univ, Grad Sch Life Sci, Sendai, Miyagi 9808577, Japan. RI Higashitani, Atsushi/G-7086-2015; OI Higashitani, Atsushi/0000-0001-6920-0594; Szewczyk, Nathaniel/0000-0003-4425-9746 NR 26 TC 16 Z9 36 U1 1 U2 4 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 1360-8185 J9 APOPTOSIS JI Apoptosis PD OCT PY 2005 VL 10 IS 5 BP 949 EP 954 DI 10.1007/s10495-005-1323-3 PG 6 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA 963HU UT WOS:000231795700003 PM 16151630 ER PT J AU Glowinski, R Shiau, LJ Kuo, YM Nasser, G AF Glowinski, R Shiau, LJ Kuo, YM Nasser, G TI The numerical simulation of friction constrained motions (II): Multiple degrees of freedom models SO APPLIED MATHEMATICS LETTERS LA English DT Article DE friction constrained motions; multiple degrees of freedom; elasto-dynamical systems; dynamical multiplier; operator-splitting AB In a previous article (Ref. [R. Glowinski, L.J. Shiau, Y.M. Kuo, G. Nasser, The numerical simulation of friction constrained motions (I): One degree of freedom models, Applied Mathematics Letters 17 (2004) 801-807]) the authors discussed the application of operator-splitting methods to the time-discretization of those mathematical relations describing the behavior of elasto-dynamical systems with friction, focusing on one-degree of freedom models. The main goal of the present article is to generalize the methodology discussed in Ref. [R. Glowinski, L.J. Shiau, Y.M. Kuo, G. Nasser, The numerical simulation of friction constrained motions (I): One degree of freedom models, Applied Mathematics Letters 17 (2004) 801-807]; there are no conceptual difficulties in doing so, the main issue being the computation of a vector-valued multiplier modeling the friction forces (or part of them). An iterative method allowing the computation of this multiplier will be discussed and the results of numerical experiments will be presented. (c) 2005 Elsevier Ltd. All rights reserved. C1 Univ Houston, Dept Math, Houston, TX 77204 USA. Univ Houston Clear Lake, Dept Math, Houston, TX 77058 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Nasser Engn, Houston, TX 77058 USA. RP Glowinski, R (reprint author), Univ Houston, Dept Math, Houston, TX 77204 USA. EM roland@math.uh.edu; shiau@cl.uh.edu; ykuo@ems.jsc.nasa.gov; nasser@nasserecs.com NR 2 TC 1 Z9 1 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0893-9659 J9 APPL MATH LETT JI Appl. Math. Lett. PD OCT PY 2005 VL 18 IS 10 BP 1108 EP 1115 DI 10.1016/j.aml.2004.10.008 PG 8 WC Mathematics, Applied SC Mathematics GA 963XK UT WOS:000231839500005 ER PT J AU Lay, OP AF Lay, OP TI Imaging properties of rotating nulling interferometers SO APPLIED OPTICS LA English DT Article ID EXTRASOLAR GIANT PLANETS; TELESCOPE; MISSION; DESIGN; ARRAY AB Nulling interferometers combine on-axis suppression with high angular resolution, making them ideal instruments for the direct detection of faint planets close to their parent star. The synthesized point-spread function for a rotating nulling interferometer utilizing phase chopping is shown to consist of a main peak, satellite peaks, and their associated sidelobes, and simple analytic expressions are derived for the modulation efficiency and angular resolution. Sufficient angular resolution is vital for the detection and characterization of multiple-planet systems and requires that some configurations be substantially larger than previously thought. The corresponding increase in stellar leakage has a major effect on performance and can be a deciding factor in the choice of array configuration. (c) 2005 Optical Society of America. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Lay, OP (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM oliver.p.lay@jpl.nasa.gov NR 20 TC 14 Z9 14 U1 0 U2 0 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 OCT 1 PY 2005 VL 44 IS 28 BP 5859 EP 5871 DI 10.1364/AO.44.005859 PG 13 WC Optics SC Optics GA 968TV UT WOS:000232186200003 PM 16231792 ER PT J AU Yeh, C Shimabukuro, F Siegel, PH AF Yeh, C Shimabukuro, F Siegel, PH TI Low-loss terahertz ribbon waveguides SO APPLIED OPTICS LA English DT Article ID MILLIMETER; TECHNOLOGY; WAVEGUIDES AB The submillimeter wave or terahertz (THz) band (1 mm-100 mu m) is one of the last unexplored frontiers in the electromagnetic spectrum. A major stumbling block hampering instrument deployment in this frequency regime is the lack of a low-loss guiding structure equivalent to the optical fiber that is so prevalent at the visible wavelengths. The presence of strong inherent vibrational absorption bands in solids and the high skin-depth losses of conductors make the traditional microstripline circuits, conventional dielectric lines, or metallic waveguides, which are common at microwave frequencies, much too lossy to be used in the THz bands. Even the modern surface plasmon polariton waveguides are much too lossy for long-distance transmission in the THz bands. We describe a concept for overcoming this drawback and describe a new family of ultra-low-loss ribbon-based guide structures and matching components for propagating single-mode THz signals. For straight runs this ribbon-based waveguide can provide an attenuation constant that is more than 100 times less than that of a conventional dielectric or metallic waveguide. Problems dealing with efficient coupling of power into and out of the ribbon guide, achieving low-loss bends and branches, and forming THz circuit elements are discussed in detail. One notes that active circuit elements can be integrated directly onto the ribbon structure (when it is made with semiconductor material) and that the absence of metallic structures in the ribbon guide provides the possibility of high-power carrying capability. It thus appears that this ribbon-based dielectric waveguide and associated components can be used as fundamental building blocks for a new generation of ultra-high-speed electronic integrated circuits or THz interconnects. (c) 2005 Optical Society of America. C1 Calif Adv Studies, Santa Monica, CA 90403 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Yeh, C (reprint author), Calif Adv Studies, 826 5th St,Suite 3, Santa Monica, CA 90403 USA. EM evepanda@aol.com; shimas@worldnet.att.net NR 30 TC 49 Z9 50 U1 0 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 OCT 1 PY 2005 VL 44 IS 28 BP 5937 EP 5946 DI 10.1364/AO.44.005937 PG 10 WC Optics SC Optics GA 968TV UT WOS:000232186200012 PM 16231801 ER PT J AU Drozdovsky, I Yan, L Chen, HW Stern, D Kennicutt, R Spinrad, H Dawson, S AF Drozdovsky, I Yan, L Chen, HW Stern, D Kennicutt, R Spinrad, H Dawson, S TI The Hubble Space Telescope ACS grism parallel survey. II. First results and a catalog of faint emission-line galaxies at z <= 1.6 SO ASTRONOMICAL JOURNAL LA English DT Article DE catalogs; galaxies : high-redshift; surveys ID STAR-FORMING GALAXIES; ALPHA LUMINOSITY FUNCTION; DISK GALAXIES; DEEP FIELD; DISTANT GALAXIES; O-II; SPECTRA; SPECTROSCOPY; UNIVERSE; Z-SIMILAR-TO-1 AB We present the first results from the Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS) Grism Parallel Survey, a large program obtaining deep, slitless ACS grism spectroscopy of high-latitude HST parallel fields. We report on 11 high Galactic latitude fields here, each with grism integration times of more than 12 ks. We identify 601 compact emission-line galaxies at z <= 1.6, reaching emission lines to a flux limit of greater than or similar to 5 x 10(-18) ergs cm(-2) s(-1) (3 sigma). We determine redshifts by cross-correlation of the target spectra with template spectra, followed by visual inspection. We measure star formation rates from the observed [O II] lambda 3727, [O III] lambda 5007, and H alpha line fluxes. Follow-up observations with the Keck telescope of one of the survey fields confirms our classification and redshifts with sigma(z) similar or equal to 0.02. This is one of the deepest emission-line surveys to date, covering a total area of 121 arcmin(2). The rough estimate of the comoving number density of emission-line galaxies in our survey at 0.3 < z < 1.3 is similar to 4.5 x 10(-3) h(70)(3) Mpc(-3). We reach deeper into the emission-line luminosity function than either the STIS or NICMOS grism parallel surveys, finding an apparent space density of emission-line galaxies several times higher than those surveys. Because of the ACS high spatial resolution, our survey is very sensitive to faint, compact galaxies with strong emission lines and weak continua. The ACS grism survey provides the comoving star formation density at z <= 1.6 at a high level of completeness. C1 CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA. St Petersburg Univ, Astron Inst, Petrodvorets 198504, Russia. MIT, Cambridge, MA 02138 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. RP Drozdovsky, I (reprint author), CALTECH, Spitzer Sci Ctr, MS 100-22, Pasadena, CA 91125 USA. OI Drozdovsky, Igor/0000-0002-5085-1319 NR 54 TC 14 Z9 14 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD OCT PY 2005 VL 130 IS 4 BP 1324 EP 1336 DI 10.1086/430884 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 969XW UT WOS:000232270200002 ER PT J AU Brown, TM Ferguson, HC Smith, E Guhathakurta, P Kimble, RA Sweigart, AV Renzini, A Rich, RM VandenBerg, DA AF Brown, TM Ferguson, HC Smith, E Guhathakurta, P Kimble, RA Sweigart, AV Renzini, A Rich, RM VandenBerg, DA TI Stellar cluster fiducial sequences with the Advanced Camera for Surveys SO ASTRONOMICAL JOURNAL LA English DT Article DE globular clusters : general; globular clusters : individual (NGC 6341, NGC 6752; NGC 104, NGC 5927, NGC 6528); open clusters and associations : individual (NGC 6791) ID METAL-POOR STARS; ALPHA-ELEMENT ABUNDANCES; HUBBLE-SPACE-TELESCOPE; GLOBULAR-CLUSTER; RADIATIVE ACCELERATIONS; POPULATION SYNTHESIS; EARLY SUBGIANTS; CCD PHOTOMETRY; MILKY-WAY; TURN-OFF AB We present color-magnitude diagrams of five Galactic globular clusters and one Galactic open cluster spanning a wide range of metallicity (-2.1 less than or similar to [Fe/H] less than or similar to +0. 3), as observed in the F606W (broad V) and F814W (I) bands with the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope. These clusters are part of two large ACS programs measuring the star formation history in the Andromeda halo, tidal stream, and outer disk. In these programs, the clusters serve as empirical isochrones and as calibrators for the transformation of theoretical isochrones to the ACS bandpasses. To make these data more accessible to the community, for each cluster we provide a ridgeline tracing the stars on the main sequence, subgiant branch, and red giant branch, plus the locus of stars on the horizontal branch. In addition, we provide the transformation of the Victoria-Regina isochrones to the ACS bandpasses. C1 Space Telescope Sci Inst, Baltimore, MD 21218 USA. Univ Calif Santa Cruz, Santa Cruz, CA 95064 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. European So Observ, D-8046 Garching, Germany. Univ Calif Los Angeles, Dept Phys & Astron, Div Astron, Los Angeles, CA 90095 USA. Univ Victoria, Dept Phys & Astron, Victoria, BC V8W 3P6, Canada. RP Brown, TM (reprint author), Space Telescope Sci Inst, 3700 San Martin Dr, Baltimore, MD 21218 USA. EM tbrown@stsci.edu; ferguson@stsci.edu; edsmith@stsci.edu; raja@ucolick.org; randy.a.kimble@nasa.gov; allen.v.sweigart@nasa.gov; arenzini@eso.org; rmr@astro.ucla.edu; davb@uvvm.uvic.ca OI Brown, Thomas/0000-0002-1793-9968 NR 51 TC 38 Z9 38 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD OCT PY 2005 VL 130 IS 4 BP 1693 EP 1706 DI 10.1086/444542 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 969XW UT WOS:000232270200026 ER PT J AU Wilking, BA Meyer, MR Robinson, JG Greene, TP AF Wilking, BA Meyer, MR Robinson, JG Greene, TP TI Optical spectroscopy of the surface population of the rho Ophiuchi molecular cloud: The first wave of star formation SO ASTRONOMICAL JOURNAL LA English DT Article DE ISM : individual (rho Ophiuchi cloud); open clusters and associations : individual (Upper Scorpius); stars : formation; stars : pre-main-sequence ID T-TAURI STARS; SCORPIUS OB ASSOCIATION; YOUNG STELLAR OBJECTS; MAIN-SEQUENCE STARS; H-ALPHA EMISSION; OPH DARK CLOUD; LOW-MASS STARS; X-RAY SOURCES; BROWN DWARFS; MAGNETOSPHERIC ACCRETION AB We present the results of optical spectroscopy of 139 stars obtained with the Hydra multiobject spectrograph. The objects extend over a 1.3 deg(2) area surrounding the main cloud of the rho Oph complex. The objects were selected from narrowband images to have H alpha in emission. Using the presence of strong H alpha emission, lithium absorption, location in the Hertzsprung-Russell diagram, or previously reported X-ray emission, we were able to identify 88 objects as young stars associated with the cloud. Strong H alpha emission was confirmed in 39 objects with line widths consistent with their origin in magnetospheric accretion columns. Two of the strongest emission-line objects are young, X-ray-emitting brown dwarf candidates with M8 spectral types. Comparisons of the bolometric luminosities and effective temperatures with theoretical models suggest a median age for this population of 2.1 Myr, which is significantly older than the ages derived for objects in the cloud core. It appears that these stars formed contemporaneously with low-mass stars in the Upper Scorpius subgroup, likely triggered by massive stars in the Upper Centaurus subgroup. C1 Univ Missouri, Dept Phys & Astron, St Louis, MO 63121 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Wilking, BA (reprint author), Univ Missouri, Dept Phys & Astron, 1 Univ Blvd, St Louis, MO 63121 USA. EM bwilking@umsl.edu; mmeyer@gould.as.arizona.edu; johnr@newton.umsl.edu; tgreene@mail.arc.nasa.gov NR 70 TC 95 Z9 95 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD OCT PY 2005 VL 130 IS 4 BP 1733 EP 1751 DI 10.1086/432758 PG 19 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 969XW UT WOS:000232270200029 ER PT J AU Stauffer, JR Rebull, LM Carpenter, J Hillenbrand, L Backman, D Hines, DC Soderblom, DR Mamajek, E Morris, P Bouwman, J Strom, SE AF Stauffer, JR Rebull, LM Carpenter, J Hillenbrand, L Backman, D Hines, DC Soderblom, DR Mamajek, E Morris, P Bouwman, J Strom, SE TI Spitzer Space Telescope observations of G dwarfs in the Pleiades: Circumstellar debris disks at 100 Myr age SO ASTRONOMICAL JOURNAL LA English DT Article DE open clusters and associations : individual (Pleiades); stars : low-mass, brown dwarfs ID LOW-MASS STARS; YOUNG OPEN CLUSTERS; SOLAR-TYPE STARS; T-TAURI STARS; ROTATIONAL VELOCITIES; OB ASSOCIATION; LITHIUM DEPLETION; MAIN-SEQUENCE; DUSTY DEBRIS; EVOLUTION AB Fluxes and upper limits in the wavelength range from 3.6 to 70 mu m from the Spitzer Space Telescope are provided for 20 solar-mass Pleiades members. One of these stars shows a probable mid-IR excess, and two others have possible excesses, presumably due to circumstellar debris disks. For the star with the largest, most secure excess flux at MIPS (Multiband Imaging Photometer for Spitzer) wavelengths, HII 1101, we derive log (L-dust/L-*) similar to -3.8 and an estimated debris disk mass of 4.2 x 10(-5) M-circle plus for an assumed uniform dust grain size of 10 mu m. If the stars with detected excesses are interpreted as stars with relatively recent, large collisional events producing a transient excess of small dust particles, the frequency of such disk transients is similar to 10% for our similar to 100 Myr, Pleiades G dwarf sample. For the stars without detected 24-70 mu m excesses, the upper limits to their fluxes correspond to approximate 3 sigma upper limits to their disk masses of 6 x 10(-6) M-circle plus using the MIPS 24 mu m upper limit or 2 x 10(-4) M-circle plus using the MIPS 70 mu m limit. These upper limit disk masses (for "warm" and "cold" dust, respectively) are roughly consistent with, but somewhat lower than, predictions of a heuristic model for the evolution of an "average" solar-mass star's debris disk based on extrapolation backward in time from current properties of the Sun's Kuiper Belt. C1 CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA. CALTECH, Dept Astron, Pasadena, CA 91125 USA. NASA, SOFIA & SETI Inst, Ames Res Ctr, Mountain View, CA 94035 USA. Univ Arizona, Steward Observ, Tucson, AZ 85726 USA. Space Sci Inst, Boulder, CO 80301 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Ctr Astrophys, Cambridge, MA 02138 USA. CALTECH, Ctr Infrared Proc & Anal, Pasadena, CA 91125 USA. Max Planck Inst Astron, D-69117 Heidelberg, Germany. Natl Opt Astron Observ, Tucson, AZ 85719 USA. RP Stauffer, JR (reprint author), CALTECH, Spitzer Sci Ctr, Mail Code 314-6,1200 E Calif Blvd, Pasadena, CA 91125 USA. EM stauffer@ipac.caltech.edu OI Rebull, Luisa/0000-0001-6381-515X NR 58 TC 44 Z9 44 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD OCT PY 2005 VL 130 IS 4 BP 1834 EP 1844 DI 10.1086/444420 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 969XW UT WOS:000232270200037 ER PT J AU Lowrance, PJ Becklin, EE Schneider, G Kirkpatrick, JD Weinberger, AJ Zuckerman, B Dumas, C Beuzit, JL Plait, P Malumuth, E Heap, S Terrile, RJ Hines, DC AF Lowrance, PJ Becklin, EE Schneider, G Kirkpatrick, JD Weinberger, AJ Zuckerman, B Dumas, C Beuzit, JL Plait, P Malumuth, E Heap, S Terrile, RJ Hines, DC TI An infrared coronagraphic survey for substellar companions SO ASTRONOMICAL JOURNAL LA English DT Review DE stars : low-mass, brown dwarfs ID SOLAR-TYPE STARS; ALL-SKY SURVEY; LOW-MASS STARS; STELLAR KINEMATIC GROUPS; BROWN DWARF COMPANIONS; ADAPTIVE OPTICS SYSTEM; URSA MAJOR GROUP; T TAURI STARS; X-RAY; LITHIUM ABUNDANCES AB We have used the F160W filter (1.4-1.8 mu m) and the coronagraph on the Near-Infrared Camera and Multi-Object Spectrometer (NICMOS) on the Hubble Space Telescope to survey 45 single stars with a median age of 0.15 Gyr, an average distance of 30 pc, and an average H magnitude of 7 mag. For the median age we were capable of detecting a 30M(J) companion at separations between 15 and 200 AU. A 5M(J) object could have been detected at 30 AU around 36% of our primaries. For several of our targets that were less than 30 Myr old, the lower mass limit was as low as 1M(J), well into the high mass planet region. Results of the entire survey include the proper-motion verification of five low-mass stellar companions, two brown dwarfs (HR7329B and TWA5B), and one possible brown dwarf binary (G1 577B/C). C1 CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA. Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. CALTECH, Ctr Infrared Proc & Anal, Pasadena, CA 91125 USA. Carnegie Inst Washington, Dept Terr Magnetism, Washington, DC 20015 USA. European So Observ, Santiago 19, Chile. Observ Grenoble, Astrophys Lab, F-38041 Grenoble, France. Sonoma State Univ, Dept Phys & Astron, Rohnert Pk, CA 94928 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Space Sci Inst, Boulder, CO 80301 USA. RP Lowrance, PJ (reprint author), CALTECH, Spitzer Sci Ctr, MS 220-6, Pasadena, CA 91125 USA. EM lowrance@ipac.caltech.edu RI heap, sara/E-2237-2012; OI Weinberger, Alycia/0000-0001-6654-7859 NR 107 TC 80 Z9 80 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-6256 J9 ASTRON J JI Astron. J. PD OCT PY 2005 VL 130 IS 4 BP 1845 EP 1861 DI 10.1086/432839 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 969XW UT WOS:000232270200038 ER PT J AU Arranz, AC Wilson, CA Connell, P Nunez, SM Blay, P Beckmann, V Reglero, V AF Arranz, AC Wilson, CA Connell, P Nunez, SM Blay, P Beckmann, V Reglero, V TI INTEGRAL observations of the Be/X-ray binary EXO 2030+375 during outburst SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE accretion, accretion disks; stars : binaries : close; stars : individual : EXO 2030+375; X-rays : binaries ID ACCRETING NEUTRON-STARS; TRANSIENT EXO 2030+375; JEM-X; LUMINOSITY DEPENDENCE; PULSAR EXO-2030+375; DISCOVERY; COMPTONIZATION; COUNTERPART; TELESCOPE; EMISSION AB We present a type-I outburst of the high-mass X-ray binary EXO 2030+375, detected during INTEGRAL's Performance and Verification phase in December 2002 (on-source time about 10(6) s). In addition, six more outbursts have been observed during INTEGRAL's Galactic Plane Scans. X-ray pulsations have been detected with a pulse period of 41.691798 +/- 0.000016 s. The X-ray luminosity in the 5-300 keV energy range was 9.7x10(36) erg s(-1), for a distance of 7.1 kpc. Two unusual features were found in the light curve, with an initial peak before the main outburst and another possible spike after the maximum. RXTE observations confirm only the existence of the initial spike. Although the initial peak appears to be a recurrent feature, the physical mechanisms producing it and the possible second spike are unknown. Moreover, a four-day delay between periastron passage and the peak of the outburst is observed. We present for the first time a 5-300 keV broad-band spectrum of this source. It can be modelled by the sum of a disk black body (kT(BB)similar to 8 keV) with either a power law model with Gamma=2.04 +/- 0.11 keV or a Comptonized component (spherical geometry, kT(e)=30 keV, tau=2.64, kT(W)=1.5 keV). C1 Univ Valencia, GACE, Inst Ciencias Mat, Valencia 46071, Spain. XD12 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Maryland, Dept Phys, Joint Ctr Astrophys, Baltimore, MD 21250 USA. RP Arranz, AC (reprint author), Univ Valencia, GACE, Inst Ciencias Mat, POB 20085, Valencia 46071, Spain. EM Ascension.Camero@uv.es RI Martinez-Nunez, Silvia/K-3029-2014 OI Martinez-Nunez, Silvia/0000-0002-5134-4191 NR 43 TC 14 Z9 14 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 OCT PY 2005 VL 441 IS 1 BP 261 EP 269 DI 10.1051/0004-6361:20053335 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 964IZ UT WOS:000231875600027 ER PT J AU Noglik, JB Walsh, RW Ireland, J AF Noglik, JB Walsh, RW Ireland, J TI Indirect calculation of the magnetic reconnection rate from flare loops SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE Sun : UV radiation; Sun : magnetic fields; Sun : corona ID SOLAR-FLARE; CORONA; INFLOW; MODEL AB High time resolution Transition Region And Coronal Explorer (TRACE) 171 and 195 angstrom observations of the evolution of flare loops on 1999 March 18 have been investigated. Given the location of the magnetic loops on the northeast solar limb and the cadence of the TRACE observations (similar to 50 s), an estimation of the footpoint velocity due to ongoing reconnection was undertaken. This was achieved by calculating the velocity at which successive loops brighten in the emission lines during the postflare phase. A typical footpoint velocity of 1.5 km s(-1) +/- 0.7 km s(-1) is obtained and a reconnection rate of similar to 0.001-0.03 is determined using the method outlined in Isobe et al. (2002, ApJ, 566, 528). This value for the reconnection rate is consistent with the regime outlined by Petschek's model for magnetic reconnection. C1 Univ Cent Lancashire, Ctr Astrophys, Preston PR2 2HE, Lancs, England. NASA, L3 Commun Govt Serv Inc, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Univ Cent Lancashire, Ctr Astrophys, Preston PR2 2HE, Lancs, England. EM jbnoglik@uclan.ac.uk NR 20 TC 13 Z9 13 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 1432-0746 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD OCT PY 2005 VL 441 IS 1 BP 353 EP 360 DI 10.1051/0004-6361:20042255 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 964IZ UT WOS:000231875600037 ER PT J AU Knodlseder, J Jean, P Lonjou, V Weidenspointner, G Guessoum, N Gillard, W Skinner, G von Ballmoos, P Vedrenne, G Roques, JP Schanne, S Teegarden, B Schonfelder, V Winkler, C AF Knodlseder, J Jean, P Lonjou, V Weidenspointner, G Guessoum, N Gillard, W Skinner, G von Ballmoos, P Vedrenne, G Roques, JP Schanne, S Teegarden, B Schonfelder, V Winkler, C TI The all-sky distribution of 511 keV electron-positron annihilation emission SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE gamma rays : observations; line : profiles; galaxy : center ID GALACTIC-CENTER REGION; GAMMA-RAY EMISSION; AL-26 LINE DATA; MILKY-WAY; CLASSICAL NOVAE; IA SUPERNOVAE; SPATIAL-DISTRIBUTION; RADIAL-DISTRIBUTION; STELLAR POPULATION; MASS-DISTRIBUTION AB We present a map of 511 keV electron- positron annihilation emission, based on data accumulated with the SPI spectrometer aboard ESA's INTEGRAL gamma- ray observatory, that covers approximately similar to 95% of the celestial sphere. Within the exposed sky area, 511 keV line emission is significantly detected towards the galactic bulge region and, at a very low level, from the galactic disk. The bulge emission is highly symmetric and is centred on the galactic centre with an extension of similar to 8 degrees. ( FWHM). The emission is equally well described by models that represent the stellar bulge or halo populations. The detection significance of the bulge emission is similar to 50 sigma, that of the galactic disk is similar to 4 sigma . The disk morphology is only weakly constrained by the present data, being compatible with both the distribution of young and old stellar populations. The 511 keV line flux from the bulge and disk components is (1.05 +/- 0.06) x 10(-3) ph cm(-2) s(-1) and (0.7 +/- 0.4) x 10(-3) ph cm(-2) s(-1), respectively, corresponding to a bulge-to-disk flux ratio in the range 1-3. Assuming a positronium fraction of f(p) = 0.93 this translates into annihilation rates of (1.5 +/- 0.1) x 10(43) s(-1) and (0.3 +/- 0.2) x 10(43) s(-1), respectively. The ratio of the bulge luminosity to that of the disk is in the range 3- 9. We find no evidence for a point-like source in addition to the di. use emission, down to a typical flux limit of similar to 10(-4) ph cm(-2) s(-1). We also find no evidence for the positive latitude enhancement that has been reported from OSSE measurements; our 3 sigma upper flux limit for this feature is 1.5 x 10(-4) ph cm(-2) s(-1). The disk emission can be attributed to the beta(+)-decay of the radioactive species Al-26 and Ti-44. The bulge emission arises from a di. erent source which has only a weak or no disk component. We suggest that Type Ia supernovae and/or low-mass X-ray binaries are the prime candidates for the source of the galactic bulge positrons. Light dark matter annihilation could also explain the observed 511 keV bulge emission characteristics. C1 CNRS, UPS, Ctr Etud Spatiale Rayonnements, F-31028 Toulouse, France. Amer Univ Sharjah, Coll Arts & Sci, Dept Phys, Sharjah, U Arab Emirates. CEA Saclay, DSM, DAPNIA, SAp, F-91191 Gif Sur Yvette, France. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. Max Planck Inst Extraterr Phys, D-85740 Garching, Germany. Estec, ESA, Sci Operat & Data Syst Div, SCI,SD, NL-2201 AZ Noordwijk, Netherlands. RP Knodlseder, J (reprint author), CNRS, UPS, Ctr Etud Spatiale Rayonnements, BP 4346, F-31028 Toulouse, France. EM knodlseder@cesr.fr RI Guessoum, Nidhal/C-3051-2013; OI GILLARD, William/0000-0003-4744-9748 NR 92 TC 202 Z9 202 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 OCT PY 2005 VL 441 IS 2 BP 513 EP 532 DI 10.1051/0004-6361:20042063 PG 20 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 965NY UT WOS:000231958600008 ER PT J AU Papadakis, IE Kazanas, D Akylas, A AF Papadakis, IE Kazanas, D Akylas, A TI Fourier-resolved spectroscopy of the XMM-Newton observations of MCG-06-30-15 SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; galaxies : Seyfert; X-rays : galaxies ID SEYFERT 1 GALAXIES; ACTIVE GALACTIC NUCLEI; X-RAY VARIABILITY; BLACK-HOLE MASS; ACCRETION DISKS; ASCA OBSERVATIONS; LONG HARD; CYG X-1; MCG-6-30-15; LINE AB We study the frequency-resolved spectra of the Seyfert galaxy MCG -06-30-15 obtained during two recent XMM-Newton observations. Splitting the Fourier spectra in soft (E less than or similar to 2keV) and hard (E greater than or similar to 2keV) bands, we find that the soft band has a variability amplitude larger than the hard one on timescales longer than 10 ks, while the opposite is true on timescales shorter than 3 ks. Both the soft- and hard-band spectra are well fitted by power laws of different indices. The spectra of the hard band become clearly softer as the Fourier frequency decreases from 7x10(-4) to 10(-5) Hz, while the spectral slope of the soft- band power-law component is independent of the Fourier frequency. The well-known broad FeK alpha feature is absent at all frequency bins; this result implies that this feature is not variable on timescales shorter than similar to 10(5) s, in agreement with recent line variability studies. Strong spectral features are also present in the soft X-ray band (at E similar or equal to 0: 7), clearly discernible in all Fourier frequency bins. This fact is consistent with the assumption that they are due to absorption by intervening matter within the source. C1 Univ Crete, Dept Phys, Iraklion 71003, Crete, Greece. Fdn Res & Technol Hellas, Inst Elect Struct & Laser, Iraklion 71003, Crete, Greece. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. Natl Observ Athens, Inst Astron & Astrophys, Athens 15236, Greece. RP Papadakis, IE (reprint author), Univ Crete, Dept Phys, Iraklion 71003, Crete, Greece. EM jhep@physics.uoc.gr; kazanas@gsfc.nasa.gov; th@astro.noa.gr RI Papadakis, Iossif/C-3235-2011; Akylas, Athanassios/K-4629-2013 NR 31 TC 22 Z9 22 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 OCT 1 PY 2005 VL 631 IS 2 BP 727 EP 732 DI 10.1086/432637 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 971EU UT WOS:000232365300006 ER PT J AU Gabel, JR Kraemer, SB Crenshaw, DM George, IM Brandt, WN Hamann, FW Kaiser, ME Kaspi, S Kriss, GA Mathur, S Nandra, K Netzer, H Peterson, BM Shields, JC Turner, TJ Zheng, W AF Gabel, JR Kraemer, SB Crenshaw, DM George, IM Brandt, WN Hamann, FW Kaiser, ME Kaspi, S Kriss, GA Mathur, S Nandra, K Netzer, H Peterson, BM Shields, JC Turner, TJ Zheng, W TI The ionized gas and nuclear environment in NGC 3783. V. Variability and modeling of the intrinsic ultraviolet absorption SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; galaxies : individual (NGC 3783); galaxies : Seyfert; ultraviolet : galaxies ID ACTIVE GALACTIC NUCLEI; NARROW-LINE REGION; ELECTRON-IMPACT-EXCITATION; STIS ECHELLE OBSERVATIONS; SEYFERT 1 GALAXIES; X-RAY; WARM ABSORBERS; PHYSICAL CONDITIONS; EMISSION-LINES; NGC 1068 AB We present results on the location, physical conditions, and geometry of the outflow in the Seyfert 1 galaxy NGC 3783 from a study of the variable intrinsic UV absorption. Based on analysis of 18 observations with the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope and six observations with the Far Ultraviolet Spectroscopic Explorer obtained between 2000 February and 2002 January, we obtain the following results: ( 1) The lowest ionization species detected in each of the three strong kinematic components ( components 1-3 at radial velocities -1350, -550, and -725 km s(-1), respectively) varied, with equivalent widths inversely correlated with the continuum flux. This indicates that the ionization structure in the absorbers responded to changes in the photoionizing flux, with variations occurring over the weekly timescales sampled by our observations. ( 2) A multicomponent model of the line-of-sight absorption covering factors, which includes an unocculted narrow emission-line region (NLR) and separate covering factors derived for the broad-line region and continuum emission sources, predicts saturation in several lines, consistent with the lack of observed variability in these lines. Differences in covering factors and kinematic structure imply that component 1 is composed of two physically distinct regions (1a and 1b). ( 3) We obtain column densities for the individual metastable levels from the resolved C III* lambda 1175 absorption complex in component 1a. Based on our computed metastable level populations, the electron density of this absorber is similar to 3x10(4) cm(-3). Combined with photoionization modeling results, this places component 1a at similar to 25 pc from the central source. ( 4) Using time-dependent calculations, we are able to reproduce the detailed variability observed in component 1 and derive upper limits on the distances for components 2 and 3 of <= 25 and <= 50 pc, respectively. ( 5) The ionization parameters derived for the higher ionization UV absorbers ( components 1b, 2, and 3 with log U approximate to -0.5) are consistent with the modeling results for the lowest ionization X-ray component, but with smaller total column density. The high-ionization UV components are found to have pressures similar to those of the three X-ray ionization components. These results are consistent with an inhomogeneous wind model for the outflow in NGC 3783, with denser, colder, lower ionization regions embedded in more highly ionized gas. ( 6) Based on the predicted emission-line luminosities, global covering factor constraints, and distances derived for the UV absorbers, they may be identified with emission- line gas observed in the inner NLR of AGNs. We explore constraints for dynamical models of AGN outflows implied by these results. C1 Univ Colorado, Ctr Astrophys & Space Astron, Boulder, CO 80309 USA. NASA, Goddard Space Flight Ctr, Catholic Univ Amer, IACS,Lab Astron & Solar Phys, Greenbelt, MD 20771 USA. Georgia State Univ, Dept Phys & Astron, Atlanta, GA 30303 USA. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. Univ Maryland Baltimore Cty, Joint Ctr Astrophys, Dept Phys, Baltimore, MD 21250 USA. Penn State Univ, Dept Astron & Astrophys, Davey Lab 525, University Pk, PA 16802 USA. Univ Florida, Dept Astron, Bryant Space Sci Ctr, Gainesville, FL 32611 USA. Johns Hopkins Univ, Dept Phys & Astron, Ctr Astrophys Sci, Baltimore, MD 21218 USA. Technion Israel Inst Technol, Dept Phys, IL-32000 Haifa, Israel. Tel Aviv Univ, Sch Phys & Astron, Raymond & Beverly Sackler Fac Exact Sci, IL-69978 Tel Aviv, Israel. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Ohio State Univ, Dept Astron, Columbus, OH 43210 USA. Univ London Imperial Coll Sci Technol & Med, Blackett Lab, Astrophys Grp, London SW7 2AW, England. Ohio Univ, Dept Phys & Astron, Clippinger Res Labs 215B, Athens, OH 45701 USA. RP Gabel, JR (reprint author), Univ Colorado, Ctr Astrophys & Space Astron, 389 UCB, Boulder, CO 80309 USA. EM jgabel@colorado.edu RI Brandt, William/N-2844-2015 OI Brandt, William/0000-0002-0167-2453 NR 56 TC 52 Z9 52 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 OCT 1 PY 2005 VL 631 IS 2 BP 741 EP 761 DI 10.1086/432682 PN 1 PG 21 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 971EU UT WOS:000232365300008 ER PT J AU Popowski, P Griest, K Thomas, CL Cook, KH Bennett, DP Becker, AC Alves, DR Minniti, D Drake, AJ Alcock, C Allsman, RA Axelrod, TS Freeman, KC Geha, M Lehner, MJ Marshall, SL Nelson, CA Peterson, BA Quinn, PJ Stubbs, CW Sutherland, W Vandehei, T Welch, D AF Popowski, P Griest, K Thomas, CL Cook, KH Bennett, DP Becker, AC Alves, DR Minniti, D Drake, AJ Alcock, C Allsman, RA Axelrod, TS Freeman, KC Geha, M Lehner, MJ Marshall, SL Nelson, CA Peterson, BA Quinn, PJ Stubbs, CW Sutherland, W Vandehei, T Welch, D CA MACHO Collaboration TI Microlensing optical depth toward the galactic bulge using clump giants from the macho survey SO ASTROPHYSICAL JOURNAL LA English DT Article DE Galaxy : center; Galaxy : stellar content; Galaxy : structure; gravitational lensing; surveys ID GRAVITATIONAL LENSING EXPERIMENT; DIFFERENCE IMAGE-ANALYSIS; EXTINCTION MAP; BAADES WINDOW; ZERO-POINT; PROJECT; EVENTS; PHOTOMETRY; BAR; DISCOVERY AB Using 7 yr of MACHO survey data, we present a new determination of the optical depth to microlensing toward the Galactic bulge. We select the sample of 62 microlensing events ( 60 unique) on clump giant sources and perform a detailed efficiency analysis. We use only the clump giant sources because these are bright bulge stars and are not as strongly affected by blending as other events. Using a subsample of 42 clump events concentrated in an area of 4.5 deg(2) with 739,000 clump giant stars, we find tau 2.17(-0.38)(+0.47) x 10(-6) at (l, b) (1.degrees 50; -2.degrees 68), somewhat smaller than found in most previous MACHO studies but in excellent agreement with recent theoretical predictions. We also present the optical depth in each of the 19 fields in which we detected events and find limits on optical depth for fields with no events. The errors in optical depth in individual fields are dominated by Poisson noise. We measure optical depth gradients of (1.06 +/- 0.71)x 10(-6) deg(-1) and (0.29 +/- 0.43)x 10(-6) deg(-1) in the Galactic latitude b and longitude l directions, respectively. Finally, we discuss the possibility of anomalous duration distribution of events in the field 104 centered on (l; b) (3 degrees.11, -3 degrees.01), as well as investigate spatial clustering of events in all fields. C1 Max Planck Inst Astrophys, D-85741 Garching, Germany. Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Notre Dame, Dept Phys, South Bend, IN 46556 USA. Univ Washington, Dept Astron, Seattle, WA 98195 USA. Goddard Space Flight Ctr, Astron & Solar Phys Lab, Greenbelt, MD 20781 USA. Pontificia Univ Catolica Chile, Dept Astron, Santiago 22, Chile. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Natl Opt Astron Observ, Tucson, AZ 85719 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Res Sch Astron & Astrophys, Weston, ACT 2611, Australia. Carnegie Observ, Pasadena, CA 91101 USA. Univ Penn, Dept Phys & Astron, Philadelphia, PA 19104 USA. Stanford Linear Accelerator Ctr, Kavli Inst Particle Astrophys & Cosmol, Menlo Pk, CA 94025 USA. European So Observ, D-85748 Garching, Germany. Univ Cambridge, Inst Astron, Cambridge CB3 0HA, England. McMaster Univ, Hamilton, ON L8S 4M1, Canada. RP Popowski, P (reprint author), Max Planck Inst Astrophys, Karl Schwarzschild Str 1,Postfach 1317, D-85741 Garching, Germany. EM popowski@mpa-garching.mpg.de; griest@astrophys.ucsd.edu; clt@ucsd.edu; kcook@igpp.ucllnl.org; bennett@emu.phys.nd.edu; becker@astro.washington.edu; alves@lasp680.gsfc.nasa.gov; dante@astro.puc.cl; ajd@astro.puc.cl; calcock@cfa.harvard.edu; robyn@noao.edu; cnelson@igpp.ucllnl.org; cstubbs@cfa.harvard.edu; vandehei@astrophys.ucsd.edu RI Stubbs, Christopher/C-2829-2012; Quinn, Peter/B-3638-2013 OI Stubbs, Christopher/0000-0003-0347-1724; NR 47 TC 72 Z9 74 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 OCT 1 PY 2005 VL 631 IS 2 BP 879 EP 905 DI 10.1086/432246 PN 1 PG 27 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 971EU UT WOS:000232365300019 ER PT J AU Thomas, CL Griest, K Popowski, P Cook, KH Drake, AJ Minniti, D Myer, DG Alcock, C Allsman, RA Alves, DR Axelrod, TS Becker, AC Bennett, DP Freeman, KC Geha, M Lehner, MJ Marshall, SL Nelson, CA Peterson, BA Quinn, PJ Stubbs, CW Sutherland, W Vandehei, T Welch, DL AF Thomas, CL Griest, K Popowski, P Cook, KH Drake, AJ Minniti, D Myer, DG Alcock, C Allsman, RA Alves, DR Axelrod, TS Becker, AC Bennett, DP Freeman, KC Geha, M Lehner, MJ Marshall, SL Nelson, CA Peterson, BA Quinn, PJ Stubbs, CW Sutherland, W Vandehei, T Welch, DL CA MACHO Collaboration TI Galactic bulge microlensing events from the MACHO collaboration SO ASTROPHYSICAL JOURNAL LA English DT Article DE catalogs; Galaxy : bulge; Galaxy : structure; gravitational lensing; stars : dwarf novae; stars : variables : other ID GRAVITATIONAL LENSING EXPERIMENT; DIFFERENCE IMAGE-ANALYSIS; LARGE-MAGELLANIC-CLOUD; SAGITTARIUS DWARF GALAXY; OPTICAL DEPTH; MILKY-WAY; DARK MATTER; PROJECT; PHOTOMETRY; HALO AB We present a catalog of 450 relatively high signal-to-noise ratio microlensing events observed by the MACHO collaboration between 1993 and 1999. The events are distributed throughout our fields, and as expected, they show a clear concentration toward the Galactic center. No optical depth is given for this sample, since no blending efficiency calculation has been performed and we find evidence for substantial blending. In a companion paper we give optical depths for the subsample of events on clump giant source stars, where blending is a less significant effect. Several events with sources that may belong to the Sagittarius dwarf galaxy are identified. For these events even relatively low dispersion spectra could suffice to classify these events as either consistent with Sagittarius membership or as non-Sagittarius sources. Several unusual events, such as microlensing of periodic variable source stars, binary lens events, and an event showing extended source effects, are identified. We also identify a number of contaminating background events as cataclysmic variable stars. C1 Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. Max Planck Inst Astrophys, D-85741 Garching, Germany. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Pontificia Univ Catolica Chile, Dept Astron, Santiago 22, Chile. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Natl Opt Astron Observ, Tucson, AZ 85719 USA. Goddard Space Flight Ctr, Astron & Solar Phys Lab, Greenbelt, MD 20781 USA. Steward Observ, Tucson, AZ 85721 USA. Univ Washington, Dept Astron, Seattle, WA 98195 USA. Univ Notre Dame, Dept Phys, South Bend, IN 46556 USA. Res Sch Astron & Astrophys, Weston, ACT 2611, Australia. Carnegie Observ, Pasadena, CA 91101 USA. Univ Penn, Dept Phys & Astron, Philadelphia, PA 19104 USA. Stanford Linear Accelerator Ctr, Kavli Inst Particle Astrophys & Cosmol, Menlo Pk, CA 94025 USA. European So Observ, D-85748 Garching, Germany. Univ Cambridge, Inst Astron, Cambridge CB3 0HA, England. McMaster Univ, Hamilton, ON L8S 4M1, Canada. RP Thomas, CL (reprint author), Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. EM clt@ucsd.edu; kgriest@ucsd.edu; popowski@mpa-garching.mpg.de; kcook@igpp.ucllnl.org; ajd@astro.puc.cl; dante@astro.puc.cl; dmyer@ucsd.edu; calcock@cfa.harvard.edu; robyn@noao.edu; alves@astro.columbia.edu; taxelrod@as.arizona.edu; becker@astro.washington.edu; cnelson@igpp.ucllnl.org; cstubbs@cfa.harvard.edu; vandehei@astrophys.ucsd.edu RI Myer, David/E-1425-2011; Stubbs, Christopher/C-2829-2012; Quinn, Peter/B-3638-2013; OI Myer, David/0000-0001-8599-3694; Stubbs, Christopher/0000-0003-0347-1724; Lehner, Matthew/0000-0003-4077-0985 NR 56 TC 18 Z9 18 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 OCT 1 PY 2005 VL 631 IS 2 BP 906 EP 934 DI 10.1086/432247 PN 1 PG 29 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 971EU UT WOS:000232365300020 ER PT J AU Kawasaki, M Ozaki, M Nagase, F Inoue, H Petre, R AF Kawasaki, M Ozaki, M Nagase, F Inoue, H Petre, R TI Ionization states and plasma structures of mixed-morphology supernova remnants observed with ASCA SO ASTROPHYSICAL JOURNAL LA English DT Article DE conduction; plasmas; radiation mechanisms : thermal; supernova remnants; X-rays : ISM ID X-RAY-EMISSION; FORMED DENSE SHELL; THERMAL CONDUCTION; DIFFUSE MEDIA; MODELING W44; HOT INTERIOR; CYGNUS LOOP; W49B; SIMULATIONS; G292.0&1.8 AB We present the results of a systematic study using ASCA of the ionization state for six "mixed-morphology'' supernova remnants (MMSNRs): IC 443, W49B, W28, W44, 3C 391, and Kes 27. MMSNRs show centrally filled, thermal X-ray emission, which contrasts with shell-like radio morphology, a set of characteristics at odds with the standard model of SNR evolution ( e. g., the Sedov model). We have therefore studied the evolution of the MM SNRs from the ionization conditions inferred from the X-ray spectra, independent of X-ray morphology. We find highly ionized plasmas approaching ionization equilibrium in all the MM SNRs. The degree of ionization is systematically higher than the plasma usually seen in shell-like SNRs. Radial temperature gradients are also observed in five remnants, with cooler plasma toward the limb. In IC 443 and W49B, we find a plasma structure consistent with shell-like SNRs, suggesting that at least some MM SNRs have experienced evolution similar to that of shell-like SNRs. In addition to the results above, we have discovered an "overionized'' ionization state in W49B, similar to that previously found in IC 443. Thermal conduction can cause the hot interior plasma to become overionized by reducing the temperature and density gradients, leading to an interior density increase and temperature decrease. Therefore, we suggest that the "center-filled'' X-ray morphology develops as the result of thermal conduction and should arise in all SNRs. This is consistent with the results that MM SNRs are near collisional ionization equilibrium, since the conduction timescale is roughly similar to the ionization timescale. Hence, we conclude that MM SNRs are those that have evolved over similar to 10(4) yr. We call this phase the "conduction phase.'' C1 Inst Space & Astronaut Sci, Sagamihara, Kanagawa 2298510, Japan. Mitsubishi Heavy Ind Co Ltd, Nagoya Guidance & Propuls Syst Works, Aichi 4858561, Japan. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. RP Kawasaki, M (reprint author), Inst Space & Astronaut Sci, Sagamihara, Kanagawa 2298510, Japan. EM rob@lheapop.gsfc.nasa.gov RI Ozaki, Masanobu/K-1165-2013 NR 46 TC 36 Z9 37 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 OCT 1 PY 2005 VL 631 IS 2 BP 935 EP 946 DI 10.1086/432591 PN 1 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 971EU UT WOS:000232365300021 ER PT J AU Low, FJ Smith, PS Werner, M Chen, C Krause, V Jura, M Hines, DC AF Low, FJ Smith, PS Werner, M Chen, C Krause, V Jura, M Hines, DC TI Exploring terrestrial planet formation in the TW hydrae association SO ASTROPHYSICAL JOURNAL LA English DT Article DE circumstellar matter; infrared : stars; planetary systems : formation ID MAIN-SEQUENCE STARS; MULTIBAND IMAGING PHOTOMETER; SPITZER-SPACE-TELESCOPE; HF-W CHRONOMETRY; TAURI STARS; HD 98800; CIRCUMSTELLAR DISKS; OB ASSOCIATION; DEBRIS SYSTEM; CATALOG AB Spitzer Space Telescope infrared measurements are presented for 24 members of the TW Hya association (TWA). High signal-to-noise ratio 24 mu m photometry is presented for all these stars, including 20 stars that were not detected by IRAS. Among these 20 stars, only a single object, TWA 7, shows excess emission at 24 mu m at the level of only 40% above the star's photosphere. TWA 7 also exhibits a strong 70 mu m excess that is a factor of 40 brighter than the stellar photosphere at this wavelength. At 70 mu m, an excess of similar magnitude is detected for TWA 13, although no 24 mu m excess was detected for this binary. For the 18 stars that failed to show measurable IR excesses, the sensitivity of the current 70 mu m observations does not rule out substantial cool excesses at levels 10-40 times above their stellar continua. Measurements of two T Tauri stars, TW Hya and Hen 6-300, confirm that their spectacular IR spectral energy distributions (SEDs) do not turn over even by 160 mu m, consistent with the expectation for their active accretion disks. In contrast, the Spitzer data for the luminous planetary debris systems in the TWA, HD 98800B and HR 4796A, are consistent with single-temperature blackbody SEDs and agree with previous IR, submillimeter, and millimeter measurements. The major new result of this study is the dramatic bimodal distribution found for the association in the form of excess emission at a wavelength of 24 mu m, indicating negligible amounts of warm (greater than or similar to 100 K) dust and debris around 20 of 24 stars in this group of very young stars. This bimodal distribution is especially striking given that the four stars in the association with strong IR excesses are greater than or similar to 100 times brighter at 24 mu m than their photospheres. Clearly, two terrestrial planetary systems, HD 98800B and HR 4796A, exist in some form. In addition, there are at least two active accreting objects, TW Hya and Hen 6-300, that may still be forming planetesimals. The remaining stars may possess significant amounts of cold dust, as in TWA 7 and 13, that have yet to be found. C1 Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Jet Propuls Lab, Pasadena, CA 91109 USA. CALTECH, Div Phys Math & Astron, Pasadena, CA 91125 USA. Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. Space Sci Inst, Boulder, CO 80303 USA. RP Low, FJ (reprint author), Univ Arizona, Steward Observ, 933 N Cherry Ave, Tucson, AZ 85721 USA. EM flow@as.arizona.edu; psmith@as.arizona.edu; mww@ipac.caltech.edu; krause@caltech.edu; jura@clotho.astro.ucla.edu NR 66 TC 97 Z9 97 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 OCT 1 PY 2005 VL 631 IS 2 BP 1170 EP 1179 DI 10.1086/432640 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 971EU UT WOS:000232365300041 ER PT J AU Hollenbach, D Gorti, U Meyer, M Kim, JS Morris, P Najita, J Pascucci, I Carpenter, J Rodmann, J Brooke, T Hillenbrand, L Mamajek, E Padgett, D Soderblom, D Wolf, S Lunine, J AF Hollenbach, D Gorti, U Meyer, M Kim, JS Morris, P Najita, J Pascucci, I Carpenter, J Rodmann, J Brooke, T Hillenbrand, L Mamajek, E Padgett, D Soderblom, D Wolf, S Lunine, J TI Formation and evolution of planetary systems: Upper limits to the gas mass in HD 105 SO ASTROPHYSICAL JOURNAL LA English DT Article DE infrared : stars; planetary systems : formation; planets and satellites : formation; solar system : formation; stars : individual (HD 105) ID T-TAURI STARS; SOLAR-TYPE STARS; SPITZER-SPACE-TELESCOPE; INFRARED SPECTROGRAPH IRS; CO FUNDAMENTAL EMISSION; MAIN-SEQUENCE STARS; HERBIG AE STARS; CIRCUMSTELLAR DISKS; GRAIN-GROWTH; PROTOPLANETARY DISKS AB We report infrared spectroscopic observations of HD 105, a nearby (similar to 40 pc) and relatively young (similar to 30 Myr) G0 star with excess infrared continuum emission, which has been modeled as arising from an optically thin circumstellar dust disk with an inner hole of size greater than or similar to 13 AU. We have used the high spectral resolution mode of the Infrared Spectrometer (IRS) on the Spitzer Space Telescope to search for gas emission lines from the disk. The observations reported here provide upper limits to the fluxes of H-2 S(0) 28 mu m, H-2 S(1) 17 mu m, H-2 S(2) 12 mu m, [Fe (II)] 26 mu m, [Si (II)] 35 mu m, and [S (I)] 25 mu m infrared emission lines. The H2 line upper limits place direct constraints on the mass of warm molecular gas in the disk: M(H-2) < 4.6, 3.8 x 10(-2), and 3.0 x 10(-3) M-J at T = 50, 100, and 200 K, respectively. We also compare the line flux upper limits to predictions from detailed thermal/chemical models of various gas distributions in the disk. These comparisons indicate that if the gas distribution has an inner hole with radius r(i,gas), the surface density at that inner radius is limited to values ranging from less than or similar to 3 g cm(-2) at r(i,gas) = 0.5 AU to 0.1 g cm(-2) at r(i,gas) = 5-20 AU. These values are considerably below the value for a minimum mass solar nebula, and suggest that less than 1 Jupiter mass (M-J) of gas (at any temperature) exists in the 1-40 AU planet-forming region. Therefore, it is unlikely that there is sufficient gas for gas giant planet formation to occur in HD 105 at this time. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Univ Calif Berkeley, Berkeley, CA 94720 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA. Natl Opt Astron Observ, Tucson, AZ 85719 USA. CALTECH, Pasadena, CA 91125 USA. Max Planck Inst Astron, Heidelberg, Germany. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Harvard Smithsonian Ctr Astrophys, Baltimore, MD 21218 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Univ Arizona, Lunar Planetary Lab, Tucson, AZ 85721 USA. RP Hollenbach, D (reprint author), NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. NR 83 TC 34 Z9 34 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 OCT 1 PY 2005 VL 631 IS 2 BP 1180 EP 1190 DI 10.1086/432638 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 971EU UT WOS:000232365300042 ER PT J AU Hesse, M Forbes, TG Birn, J AF Hesse, M Forbes, TG Birn, J TI On the relation between reconnected magnetic flux and parallel electric fields in the solar corona SO ASTROPHYSICAL JOURNAL LA English DT Article DE MHD; sun : corona; sun : magnetic fields ID MASS EJECTIONS; CURRENT SHEETS; CONNECTIVITY; MAGNETOTAIL; EVOLUTION; REGION; MOTION; FLARES; LOOPS AB Analytical theory and kinematic models are applied to magnetic reconnection in the solar corona. The emphasis of the present investigation is on the relation between the reconnection electric field, the reconnection rate, and the change in magnetic connectivity among photospheric magnetic footpoints. The results are not tied to the presence or absence of specific topological features of the magnetic field, such as a separatrix layer or separators. It is shown that the critical element in determining the location of ribbon-like bright features on the solar surface may be the parallel electric field, integrated along magnetic field lines. A general relation between the change of the reconnected magnetic flux and the integrated parallel electric field is derived. The results of this analysis are applied to the solar coronal case by means of two kinematic models, one of which affords a fully analytical treatment. The results show that reconnection-induced changes of magnetic connectivity on the corona-photosphere interface are directly related to the maximum value of the field line-integrated parallel electric field. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ New Hampshire, Durham, NH 03824 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Hesse, M (reprint author), NASA, Goddard Space Flight Ctr, Code 696, Greenbelt, MD 20771 USA. EM michael.hesse@nasa.gov; terry.forbes@unh.edu; jbirn@lanl.gov RI Hesse, Michael/D-2031-2012; NASA MMS, Science Team/J-5393-2013 OI NASA MMS, Science Team/0000-0002-9504-5214 NR 39 TC 43 Z9 43 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 OCT 1 PY 2005 VL 631 IS 2 BP 1227 EP 1238 DI 10.1086/432677 PN 1 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 971EU UT WOS:000232365300046 ER PT J AU Clark, DM Christopher, MH Eikenberry, SS Brandl, BR Wilson, JC Carson, JC Henderson, CP Hayward, TL Barry, DJ Ptak, AF Colbert, EJM AF Clark, DM Christopher, MH Eikenberry, SS Brandl, BR Wilson, JC Carson, JC Henderson, CP Hayward, TL Barry, DJ Ptak, AF Colbert, EJM TI The ultraluminous X-ray source X-37 is a background quasar in the Antennae galaxies SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : starburst; quasars : general; X-rays : galaxies ID MASS BLACK-HOLES; CHANDRA OBSERVATIONS; LUMINOSITY FUNCTION; DATA RELEASE; NGC-4038/4039; EXTINCTION; CATALOG AB In this Letter we report that a bright, X-ray source in the Antennae galaxies (NGC 4038/9), previously identified as an ultraluminous X-ray source (ULX), is in fact a background quasar. We identify an isolated infrared and optical counterpart within 0.'' 3 +/- 0.'' 5 of the X-ray source X-37. After acquiring an optical spectrum of its counterpart, we use the narrow [O III] and broad H alpha emission lines to identify X-37 as a quasar at a redshift of z = 0.26. Through a U, V, and photometric analysis, we demonstrate that most of the observable light along this line of sight is from the quasar. We discuss the implications of this discovery and the importance of acquiring spectra for optical and IR counterparts to ULXs. C1 Univ Florida, Dept Astron, Gainesville, FL 32611 USA. CALTECH, Dept Astron, Pasadena, CA 91125 USA. Leiden Observ, NL-2300 RA Leiden, Netherlands. Univ Virginia, Dept Astron, Charlottesville, VA 22903 USA. Jet Prop Lab, Pasadena, CA 91109 USA. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. AURA Inc, Gemini Observ, La Serena, Chile. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. RP Clark, DM (reprint author), Univ Florida, Dept Astron, POB 112055, Gainesville, FL 32611 USA. EM dmclark@astro.ufl.edu RI Ptak, Andrew/D-3574-2012 NR 27 TC 16 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 OCT 1 PY 2005 VL 631 IS 2 BP L109 EP L112 DI 10.1086/497333 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 971EX UT WOS:000232365700003 ER PT J AU Rykoff, ES Yost, SA Krimm, HA Aharonian, F Akerlof, CW Alatalo, K Ashley, MCB Barthelmy, SD Gehrels, N Gogus, E Guver, T Horns, D Kiziloglu, U McKay, TA Ozel, M Phillips, A Quimby, RM Rujopakarn, W Schaefer, BE Smith, DA Swan, HF Vestrand, WT Wheeler, JC Wren, J AF Rykoff, ES Yost, SA Krimm, HA Aharonian, F Akerlof, CW Alatalo, K Ashley, MCB Barthelmy, SD Gehrels, N Gogus, E Guver, T Horns, D Kiziloglu, U McKay, TA Ozel, M Phillips, A Quimby, RM Rujopakarn, W Schaefer, BE Smith, DA Swan, HF Vestrand, WT Wheeler, JC Wren, J TI Prompt optical detection of GRB 050401 with ROTSE-IIIa SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts ID GAMMA-RAY BURST; EMISSION; AFTERGLOWS AB The ROTSE-IIIa telescope at Siding Spring Observatory, Australia, detected prompt optical emission from Swift GRB 050401. We present observations of the early optical afterglow, first detected by the ROTSE-IIIa telescope 33 s after the start of gamma-ray emission, contemporaneous with the brightest peak of this emission. This GRB was neither exceptionally long nor bright. This is the first prompt optical detection of a GRB of typical duration and luminosity. We find that the early afterglow decay does not deviate significantly from the power-law decay observable at later times and is uncorrelated with the prompt gamma-ray emission. We compare this detection with the other two GRBs with prompt observations, GRB 990123 and GRB 041219a. All three bursts exhibit quite different behavior at early times. C1 Univ Michigan, Dept Phys, Randall Lab 2477, Ann Arbor, MI 48109 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Space Res Assoc, Columbia, MD 21044 USA. Max Planck Inst Kernphys, D-69117 Heidelberg, Germany. Univ New S Wales, Sch Phys, Dept Astrophys & Opt, Sydney, NSW 2052, Australia. Sabanci Univ, Fac Engn & Nat Sci, TR-34958 Istanbul, Turkey. Univ Istanbul, Fac Sci, Dept Astron & Space Sci, TR-34119 Istanbul, Turkey. Middle E Tech Univ, Dept Phys, TR-06531 Ankara, Turkey. Canakkale Onsekiz Mart Univ, Dept Phys, TR-17020 Canakkale, Turkey. Univ Texas, Dept Astron, Austin, TX 78712 USA. Louisiana State Univ, Dept Phys & Astron, Baton Rouge, LA 70803 USA. Los Alamos Natl Lab, Space & Remote Sensing Sci Grp, Los Alamos, NM 87545 USA. RP Rykoff, ES (reprint author), Univ Michigan, Dept Phys, Randall Lab 2477, 450 Church St, Ann Arbor, MI 48109 USA. EM erykoff@umich.edu RI Guver, Tolga/C-1408-2011; Horns, Dieter/C-9727-2011; Gehrels, Neil/D-2971-2012; Barthelmy, Scott/D-2943-2012; Rujopakarn, Wiphu/E-7849-2012; McKay, Timothy/C-1501-2009; Guver, Tolga/B-1039-2014 OI Alatalo, Katherine/0000-0002-4261-2326; Rujopakarn, Wiphu/0000-0002-0303-499X; Flewelling, Heather/0000-0002-1050-4056; McKay, Timothy/0000-0001-9036-6150; Guver, Tolga/0000-0002-3531-9842 NR 19 TC 56 Z9 56 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 OCT 1 PY 2005 VL 631 IS 2 BP L121 EP L124 DI 10.1086/497370 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 971EX UT WOS:000232365700006 ER PT J AU Flaccomio, E Micela, G Sciortino, S Feigelson, ED Herbst, W Favata, F Harnden, FR Vrtilek, SD AF Flaccomio, E Micela, G Sciortino, S Feigelson, ED Herbst, W Favata, F Harnden, FR Vrtilek, SD TI Rotational modulation of X-ray emission in Orion Nebula young stars SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE open clusters and associations : individual (Orion Nebula Cluster); stars : activity; stars : low-mass, brown dwarfs; stars : pre-main-sequence; X-rays : stars ID T-TAURI STARS; MAIN-SEQUENCE STARS; STELLAR CORONAE; ACCRETION; CLUSTER; VARIABILITY; POPULATION; PROTOSTARS; ASTRONOMY; REGIONS AB We investigate the spatial distribution of X-ray-emitting plasma in a sample of young Orion Nebula Cluster stars by modulation of their X-ray light curves due to stellar rotation. The study, part of the Chandra Orion Ultradeep Project ( COUP), is made possible by the exceptional length of the observation: 10 days of ACIS integration during a time span of 13 days, yielding a total of 1616 detected sources in the 17' x 17' field of view. We here focus on a sub-sample of 233 X-ray-bright stars with known rotational periods. We search for X-ray modulation using the Lomb Normalized Periodogram method. X-ray modulation related to the rotation period is detected in at least 23 stars with periods between 2 and 12 days and relative amplitudes ranging from 20% to 70%. In 16 cases, the X-ray modulation period is similar to the stellar rotation period, while in 7 cases it is about half that value, possibly due to the presence of X-ray-emitting structures at opposite stellar longitudes. These results constitute the largest sample of low-mass stars in which X-ray rotational modulation has been observed. The detection of rotational modulation indicates that the X-ray-emitting regions are distributed inhomogeneneously in longitude and do not extend to distances significantly larger than the stellar radius. Modulation is observed in stars with saturated activity levels (L-X/ L-bol similar to 10(-3)) showing that saturation is not due to the filling of the stellar surface with X-ray-emitting regions. C1 INAF, Osservatorio Astron Palermo Giuseppe S Vaiana, I-90134 Palermo, Italy. Penn State Univ, Dept Astron & Astrophys, Davey Lab 525, University Pk, PA 16802 USA. Wesleyan Univ, Dept Astron, Middletown, CT 06459 USA. European Space Agcy, Res & Sci Support Dept, Div Astrophys, NL-2200 AG Noordwijk, Netherlands. Smithsonian Astrophys Lab, Cambridge, MA 02138 USA. NASA Headquarters, Universe Div, Sci Mission Directorate, Washington, DC USA. RP Flaccomio, E (reprint author), INAF, Osservatorio Astron Palermo Giuseppe S Vaiana, Piazza Parlamento 1, I-90134 Palermo, Italy. EM ettoref@astropa.unipa.it OI Flaccomio, Ettore/0000-0002-3638-5788 NR 48 TC 59 Z9 59 U1 0 U2 1 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 OCT PY 2005 VL 160 IS 2 BP 450 EP 468 DI 10.1086/432419 PG 19 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 969YC UT WOS:000232270900007 ER PT J AU Doerr, DF Ratliff, DA Sithole, J Convertino, VA AF Doerr, DF Ratliff, DA Sithole, J Convertino, VA TI Stroke volume during orthostatic challenge: Comparison of two non-invasive methods SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article DE photoplethysmography; impedance cardiography; tilt table testing ID IMPEDANCE CARDIOGRAPHY; BLOOD-PRESSURE; SPACEFLIGHT; INTOLERANCE; RESPONSES; HYPOTENSION; RESISTANCE; EXERCISE; FLIGHT AB Background: Real time non-invasive determination of stroke volume (SV) is important to astronaut orthostatic testing. We compared simultaneous estimates of SV calculated from peripheral pulse waveforms with a more conventional non-invasive technique. Methods: Ten men and nine women completed 12-min protocols. The relative change (%Delta) in beat-to-beat SV was estimated non-invasively from changes in pulse waveforms measured by application of infrared finger photoplethysmography (IFP) and thoracic impedance cardiography (TIC). The %Delta SV values were calculated from continuous measurements in the supine posture and over the first 10 s (T1), second 10 s (T2), and 3 min (T3) of 80 degrees head-up tilt (HUT). Results: Average %Delta SV measured by IFP at T1 (-11.7 +/- 13.7%) was statistically less than the average %Delta SV measured by TIC at T1 (-21.7 +/- 3.1%), while average %Delta SV measured by IFP at T2 (-16.2 +/- 3.9%) and T3 (-19.1 +/- 3.8%) were not statistically distinguishable from the average %Delta SV measured by TIC at T2 (-21.8 +/- 2.5%), and T3 (-22.6 +/- 2.9%). Correlation coefficients (r(2)) between IFP and TIC were 0.117 (T1), 0.387 (T2), and 0.718 (T3). Conclusion: IFP provides beat-to-beat (real-time) assessment of %Delta SV after 20 s of transition to an orthostatic challenge that is comparable to TIC. IFP technology flown during space missions can be used to assess physiological status and countermeasure effectiveness for orthostatic problems that may arise in astronauts after spaceflight. While the peripherally measured IFP response is delayed, the ease of implementing this monitor in the field is advantageous. C1 USA, Inst Surg Res, Ft Sam Houston, TX 78234 USA. NASA, Technol Implementat Branch, Kennedy Space Ctr, FL USA. NASA, Bionet Corp, Kennedy Space Ctr, FL USA. NASA, Spaceflight & Life Sci Training Program, Kennedy Space Ctr, FL USA. RP Convertino, VA (reprint author), USA, Inst Surg Res, 3400 Rawley E Chambers Ave,Bldg 3611, Ft Sam Houston, TX 78234 USA. EM victor.convertino@amedd.army.mil NR 18 TC 1 Z9 2 U1 0 U2 1 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 OCT PY 2005 VL 76 IS 10 BP 935 EP 939 PG 5 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 970YE UT WOS:000232347500004 PM 16235876 ER PT J AU Gutzler, DS Kim, HK Higgins, RW Juang, HMH Kanamitsu, M Mitchell, K Mo, K Pegion, P Ritchie, E Schemm, JK Schubert, S Song, Y Yang, R AF Gutzler, DS Kim, HK Higgins, RW Juang, HMH Kanamitsu, M Mitchell, K Mo, K Pegion, P Ritchie, E Schemm, JK Schubert, S Song, Y Yang, R TI The North American Monsoon Model Assessment Project - Integrating numerical modeling into a field-based process study SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID MEXICAN MONSOON; SYSTEM C1 Univ New Mexico, Dept Earth & Planetary Sci, Albuquerque, NM 87131 USA. NOAA, NCEP NWS, Climate Predict Ctr, Camp Springs, MD USA. Univ Calif San Diego, Inst Oceanog, San Diego, CA 92103 USA. NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Greenbelt, MD 20771 USA. Sci Applicat Int Corp, Beltsville, MD USA. RP Gutzler, DS (reprint author), Univ New Mexico, Dept Earth & Planetary Sci, MSC03-2040, Albuquerque, NM 87131 USA. EM gutzler@unm.edu RI Pegion, Philip/E-5247-2012; Ritchie, Elizabeth/B-4232-2016; OI Ritchie, Elizabeth/0000-0002-3413-5830; Gutzler, David/0000-0001-6476-8412 NR 5 TC 34 Z9 34 U1 0 U2 3 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0003-0007 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD OCT PY 2005 VL 86 IS 10 BP 1423 EP 1429 DI 10.1175/BAMS-86-10-1423 PG 7 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 977GD UT WOS:000232790200016 ER PT J AU Thorne, PW Karl, TR Coleman, H Folland, CK Murray, B Parker, DE Ramaswamy, V Rossow, W Scaife, AA Tett, SFB AF Thorne, PW Karl, TR Coleman, H Folland, CK Murray, B Parker, DE Ramaswamy, V Rossow, W Scaife, AA Tett, SFB TI Vertical profiles of temperature trends SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Editorial Material ID SURFACE C1 Met Off, Hadley Ctr Climate Predict & Res, Exeter EX4 1PB, Devon, England. Natl Climat Ctr, Asheville, NC USA. NOAA, Off Global Programs, Silver Spring, MD 20910 USA. Geophys Fluid Dynam Lab, Princeton, NJ USA. NASA, Goddard Inst Space Studies, New York, NY 10025 USA. Univ Reading, Hadley Ctr Climate Predict & Res, Reading Unit, Reading, Berks, England. RP Thorne, PW (reprint author), Met Off, Hadley Ctr Climate Predict & Res, Fitzroy Rd, Exeter EX4 1PB, Devon, England. EM Peter.Thorne@metoffice.gov.uk RI Tett, Simon/B-1504-2013; Folland, Chris/I-2524-2013; Thorne, Peter/F-2225-2014; Rossow, William/F-3138-2015 OI Tett, Simon/0000-0001-7526-560X; Thorne, Peter/0000-0003-0485-9798; NR 9 TC 2 Z9 2 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0003-0007 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD OCT PY 2005 VL 86 IS 10 BP 1471 EP 1476 DI 10.1175/BAMS-86-10-1471 PG 6 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 977GD UT WOS:000232790200022 ER PT J AU Johnson, PV McConkey, JW Tayal, SS Kanik, I AF Johnson, PV McConkey, JW Tayal, SS Kanik, I TI Collisions of electrons with atomic oxygen: current status (vol 83, pg 589, 2005) SO CANADIAN JOURNAL OF PHYSICS LA English DT Correction C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Windsor, Dept Phys, Windsor, ON N9B 3P4, Canada. Clark Atlanta Univ, Dept Phys, Atlanta, GA 30314 USA. RP Johnson, PV (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM Paul.V.Johnson@jpl.nasa.gov RI Johnson, Paul/D-4001-2009 OI Johnson, Paul/0000-0002-0186-8456 NR 1 TC 1 Z9 1 U1 0 U2 0 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA, ONTARIO K1A 0R6, CANADA SN 0008-4204 J9 CAN J PHYS JI Can. J. Phys. PD OCT PY 2005 VL 83 IS 10 BP 1071 EP 1072 DI 10.1139/P05-061 PG 2 WC Physics, Multidisciplinary SC Physics GA 978EN UT WOS:000232856500009 ER PT J AU Vertrees, RA Das, GC Popov, VL Coscio, AM Goodwin, TJ Logrono, R Zwischenberger, JB Boor, PJ AF Vertrees, RA Das, GC Popov, VL Coscio, AM Goodwin, TJ Logrono, R Zwischenberger, JB Boor, PJ TI Synergistic interaction of hyperthermia and gemcitabine in lung cancer SO CANCER BIOLOGY & THERAPY LA English DT Article DE hyperthermia; gemcitabine; lung cancer; apoptosis; caspase-3; synergistic ID INDUCED SYSTEMIC HYPERTHERMIA; HEAT-SHOCK-PROTEIN; PHASE-II TRIAL; CELL-CYCLE; PLUS CISPLATIN; HARVEY RAS; IN-VITRO; CHEMOTHERAPY; APOPTOSIS; SURVIVAL AB Hyperthermia increases cytotoxicity of various antineoplastic agents. We investigated the cytotoxic effects of Gemcitabine and/or hyperthermia on BZR-T33 (human non-smallcell lung cancer cells) in vitro and in immune-suppressed athymic nude mice. Isobologram analysis of monolayer cell cultures for cytotoxicity demonstrates a synergistic interaction between hyperthermia and Gemcitabine. Clonogenic results show significant reductions in surviving fractions and colony size for both therapies; greatest reduction was for the combined therapy group. Using cell cycle analysis, hyperthermia enhanced Gemcitabineinduced G2-M arrest resulting in destruction of 3.5 log cells. Apoptotic studies (Annexin-VFITC staining) showed that hyperthermia augmented Gemcitabine-induced apoptosis. Transmission electron microscopy demonstrated pathology observed in cultures exposed to either therapy present in cultures exposed to both therapies. Studies in nude mice show that the combination therapy group had both an initial decrease in tumor size, and a significantly delayed rate of growth. Additionally, using tumor material harvested from nude mice two days after end to treatment reveals a significantly greater apoptotic index and significantly smaller mitotic index for the combined therapy group. Western blots of the same tumor material, showed that heat shock protein 70 was not significantly increased, however, caspase-3 activity of was significantly increased because of the combined therapy. In conclusion, the combined therapy is synergistic in effect because of hyperthermia enhancing Gemcitabine-induced apoptosis. C1 Univ Texas, Med Branch, Div Cardiothorac Surg, Galveston, TX 77555 USA. Univ Texas, Med Branch, Dept Pathol, Galveston, TX 77555 USA. Univ Texas, Med Branch, Sch Med, Galveston, TX 77555 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Vertrees, RA (reprint author), Univ Texas, Med Branch, Div Cardiothorac Surg, 301 Univ Blvd, Galveston, TX 77555 USA. EM rvertree@utmb.edu NR 46 TC 26 Z9 30 U1 0 U2 8 PU LANDES BIOSCIENCE PI GEORGETOWN PA 810 SOUTH CHURCH STREET, GEORGETOWN, TX 78626 USA SN 1538-4047 J9 CANCER BIOL THER JI Cancer Biol. Ther. PD OCT PY 2005 VL 4 IS 10 BP 1144 EP 1153 PG 10 WC Oncology SC Oncology GA 022GO UT WOS:000236043700023 PM 16138007 ER PT J AU Hinkov, I Farhat, S Scott, CD AF Hinkov, I Farhat, S Scott, CD TI Influence of the gas pressure on single-wall carbon nanotube formation SO CARBON LA English DT Article DE carbon nanotubes; arc discharge; modeling; BET surface area ID FULLERENE SYNTHESIS; ARC-DISCHARGE; ELECTRIC-ARC; ADSORPTION; MECHANISM; KINETICS; REACTOR; GROWTH; MODEL; DIAMETER AB Experiments and modeling are performed to predict the effect of gas pressure on species distributions and nanotube growth rate under specific conditions of synthesis of single-wall carbon nanotubes (SWCNTs) by arc discharge. Numerical results are compared with experiments in order to find a consistent correlation between the nanotube growth and the pressure. We use argon and helium as buffer gases with a total pressure varied between 0.1 and 1 bar. We experimentally observe that both the anode erosion rate and the Brunauer Emmett-Teller (BET) surface area of the as-produced nanotube soot material are very sensitive to the total gas pressure in the reactor. (C) 2005 Elsevier Ltd. All rights reserved. C1 Univ Paris 13, Dept Chem Engn, LIMHP, F-93430 Villetaneuse, France. NASA, Lyndon B Johnson Space Ctr ES3, Houston, TX 77058 USA. RP Farhat, S (reprint author), Univ Paris 13, Dept Chem Engn, LIMHP, Ave JB Clement, F-93430 Villetaneuse, France. EM farhat@limhp.univ-paris13.fr NR 39 TC 29 Z9 29 U1 0 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0008-6223 J9 CARBON JI Carbon PD OCT PY 2005 VL 43 IS 12 BP 2453 EP 2462 DI 10.1016/j.carbon.2005.04.026 PG 10 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 967LT UT WOS:000232093400003 ER PT J AU Shoemaker, WC Bayard, DS Wo, CCJ Chan, LS Chien, LC Lu, K Jelliffe, RW AF Shoemaker, WC Bayard, DS Wo, CCJ Chan, LS Chien, LC Lu, K Jelliffe, RW TI Outcome prediction in chest injury by a mathematical search and display program SO CHEST LA English DT Article DE cardiac index; chest injury; noninvasive hemodynamic monitoring; outcome prediction; stochastic analysis and control program; tissue perfusion by transcutaneous O-2 ID CRITICALLY ILL PATIENTS; RISK SURGICAL PATIENTS; OXYGEN DELIVERY; CONSENSUS-CONFERENCE; EMERGENCY PATIENTS; CLINICAL-TRIAL; TRAUMA; VALUES; ALTERNATIVES; OPTIMIZATION AB Objective: This study applies a stochastic or probability search and display model to prospectively predict outcome and to evaluate therapeutic effects in a consecutively, monitored series of 396 patients with severe thoracic and thoracoabdominal injuries. Study design: Prospective observational study of outcome prediction using noninvasive hemodynamic monitoring by previously designed protocols and tested against actual outcome at hospital discharge in a level 1 trauma service of a university-run, inner-city public hospital. Methods: Cardiac index (CI), heart rate (HR), mean arterial pressure (NIAP), arterial oxygen saturation measured by pulse oximetry (SpO(2)), transcutaneous oxygen tension (PtcO(2)), and transcutaneous carbon dioxide tension (PtcCO(2)) were monitored beginning shortly after admission to the emergency department. The stochastic search and display model with a decision support program based on noninvasive hemodynamic monitoring was applied to 396 severely ill patients with major thoracic and thoracoabdominal trauma. The survival probability (SP) was calculated during initial resuscitation continuously until patients were stabilized, and compared with the actual outcome when the patient was discharged from the hospital usually a week or more later. Results: The CI, SpO(2), PtcO(2), and MAP were appreciably higher in survivors than in nonsurvivors. HR and PtcCO(2) were higher in the nonsurvivors. The calculated SP in the first 24-h observation period of survivors of chest wounds averaged 83 +/- 18% (+/- SD) and 62 +/- 19% for nonsurvivors. Misclassifications were 9.6%. The relative effects of alternative therapies were evaluated before and after therapy, using hemodynamic monitoring and SP as criteria. Conclusions: Noninvasive hemodynamic monitoring with an information system pro-sided a feasible approach to early outcome predictions and therapeutic decision support. C1 LAC & USC, Med Ctr, Lab Appl Pharmacokinet, Los Angeles, CA 90033 USA. LAC & USC, Med Ctr, Dept Surg, Los Angeles, CA 90033 USA. Univ So Calif, Keck Sch Med, Los Angeles, CA USA. Jet Propuls Lab, Pasadena, CA USA. RP Shoemaker, WC (reprint author), LAC & USC, Med Ctr, Lab Appl Pharmacokinet, Room 9900,1200 N State St, Los Angeles, CA 90033 USA. EM wcshoemaker00@hotmail.com FU NCRR NIH HHS [RR-11526]; NIGMS NIH HHS [GM-65619] NR 34 TC 3 Z9 3 U1 1 U2 2 PU AMER COLL CHEST PHYSICIANS PI NORTHBROOK PA 3300 DUNDEE ROAD, NORTHBROOK, IL 60062-2348 USA SN 0012-3692 J9 CHEST JI Chest PD OCT PY 2005 VL 128 IS 4 BP 2739 EP 2748 DI 10.1378/chest.128.4.2739 PG 10 WC Critical Care Medicine; Respiratory System SC General & Internal Medicine; Respiratory System GA 975RK UT WOS:000232679400122 PM 16236950 ER PT J AU Bailey, DA Rhines, PB Hakkinen, S AF Bailey, DA Rhines, PB Hakkinen, S TI Formation and pathways of north atlantic deep water in a coupled ice-ocean model of the arctic-north atlantic oceans SO CLIMATE DYNAMICS LA English DT Article ID THERMOHALINE CIRCULATION; DECADAL VARIABILITY; HEAT-TRANSPORT; OVERTURNING CIRCULATION; GENERAL-CIRCULATION; CLIMATE VARIABILITY; FRAM STRAIT; NORDIC SEAS; OSCILLATION; OVERFLOW AB We investigate the formation process and pathways of deep water masses in a coupled ice-ocean model of the Arctic and North Atlantic Oceans. The intent is to determine the relative roles of these water masses from the different source regions (Arctic Ocean, Nordic Seas, and Subpolar Atlantic) in the meridional overturning circulation. The model exhibits significant decadal variability in the deep western boundary current and the overturning circulation. We use detailed diagnostics to understand the process of water mass formation in the model and the resulting effects on the North Atlantic overturning circulation. Particular emphasis is given to the multiple sources of North Atlantic Deep Water, the dominant deep water masses of the world ocean. The correct balance of Labrador Sea, Greenland Sea and Norwegian Sea sources is difficult to achieve in climate models, owing to small-scale sinking and convection processes. The global overturning circulation is described as a function of potential temperature and salinity, which more clearly signifies dynamical processes and clarifies resolution problems inherent to the high latitude oceans. We find that fluxes of deep water masses through various passages in the model are higher than observed estimates. Despite the excessive volume flux, the Nordic Seas overflow waters are diluted by strong mixing and enter the Labrador Sea at a lighter density. Through strong subpolar convection, these waters along with other North Atlantic water masses are converted into the densest waters [similar density to Antarctic Bottom Water (AABW)] in the North Atlantic. We describe the diminished role of salinity in the Labrador Sea, where a shortage of buoyant surface water (or excess of high salinity water) leads to overly strong convection. The result is that the Atlantic overturning circulation in the model is very sensitive to the surface heat flux in the Labrador Sea and hence is correlated with the North Atlantic Oscillation. As strong subpolar convection is found in other models, we discuss broader implications. C1 George Mason Univ, Ctr Ocean Land Atmosphere Studies, Beltsville, MD 20705 USA. Univ Washington, Sch Oceanog, Seattle, WA 98195 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD USA. RP Bailey, DA (reprint author), George Mason Univ, Ctr Ocean Land Atmosphere Studies, 4041 Powder Mill Rd,Suite 302, Beltsville, MD 20705 USA. EM bailey@cola.iges.org RI Hakkinen, Sirpa/E-1461-2012 NR 66 TC 25 Z9 25 U1 3 U2 15 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 0930-7575 J9 CLIM DYNAM JI Clim. Dyn. PD OCT PY 2005 VL 25 IS 5 BP 497 EP 516 DI 10.1007/s00382-005-0050-3 PG 20 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 978YM UT WOS:000232909000004 ER PT J AU Miller, CE Brown, LR Toth, RA Benner, DC Devi, VM AF Miller, CE Brown, LR Toth, RA Benner, DC Devi, VM TI Spectroscopic challenges for high accuracy retrievals of atmospheric CO2 and the Orbiting Carbon Observatory (OCO) experiment SO COMPTES RENDUS PHYSIQUE LA English DT Article DE carbon dioxide (CO2); Orbiting Carbon Observatory (OCO); near infrared spectroscopy ID 20 MU-M; MULTISPECTRUM FITTING PROCEDURE; SELF-BROADENING COEFFICIENTS; WING REGIONS; LINE PARAMETERS; ROVIBRATIONAL INTENSITIES; SHIFT COEFFICIENTS; ABSORPTION-BANDS; OVERTONE BAND; (CO)-C-12-O-16 AB The space-based Orbiting Carbon Observatory (OCO) mission will achieve global measurements needed to distinguish spatial and temporal gradients in the CO2 column. Scheduled by NASA to launch in 2008, the instrument will obtain averaged dry air mole fraction (X-CO2) with a precision of I part per million (0.3%) in order to quantify the variation of CO2 sources and sinks and to improve future climate forecasts. Retrievals Of X-CO2 from ground-based measurements require even higher precisions to validate the satellite data and link them accurately and without bias to the World Meteorological Organization (WMO) standard for atmospheric CO2 observations. These retrievals will require CO2 spectroscopic parameters with unprecedented accuracy. Here we present the experimental and data analysis methods implemented in laboratory studies in order to achieve this challenging goal. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Coll William & Mary, Dept Phys, Williamsburg, VA 23187 USA. RP Miller, CE (reprint author), CALTECH, Jet Prop Lab, MS 183-501,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM charles.e.miller@jpl.nasa.gov NR 52 TC 76 Z9 76 U1 1 U2 13 PU ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER PI PARIS PA 23 RUE LINOIS, 75724 PARIS, FRANCE SN 1631-0705 J9 CR PHYS JI C. R. Phys. PD OCT PY 2005 VL 6 IS 8 BP 876 EP 887 DI 10.1016/j.crhy.2005.09.005 PG 12 WC Astronomy & Astrophysics; Physics, Multidisciplinary SC Astronomy & Astrophysics; Physics GA 985PI UT WOS:000233389900007 ER PT J AU Tseng, HC Culpepper, BJ AF Tseng, HC Culpepper, BJ TI Sinkhole intrusion in mobile ad hoc networks: The problem and some detection indicators SO COMPUTERS & SECURITY LA English DT Article DE sinkhole; intrusion detection; mobile ad hoc networks; dynamic source routing; rule-based system AB We analyze the "sinkhole" problem in the context of the Dynamic Source Routing (DSR) protocol for wireless mobile ad hoc networks (MANETs). The sinkhole effect is caused by attempts to draw all network traffic to malicious nodes that broadcast fake shortest path routing information. Two reliable indicators of sinkhole intrusion are proposed and analyzed. We will study how these sinkholes may be detected and term such as sinkhole intrusion detection. One indicator is based on the sequence number in the routing message and the other one is related to the proportion of the routes that travel to a suspected node. Threshold values that imply possible sinkhole intrusion are derived for these two indicators. The simulation results show that the indicators are consistent and reliable for detecting sinkhole intrusion. (C) 2005 Elsevier Ltd. All rights reserved. C1 San Jose State Univ, Dept Comp Sci, San Jose, CA 95192 USA. NASA, Ames Res Ctr, Neuroengn Lab, Moffett Field, CA 94305 USA. RP San Jose State Univ, Dept Comp Sci, San Jose, CA 95192 USA. EM tseng@cs.sjsu.edu NR 23 TC 7 Z9 8 U1 0 U2 1 PU ELSEVIER ADVANCED TECHNOLOGY PI OXFORD PA OXFORD FULFILLMENT CENTRE THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0167-4048 EI 1872-6208 J9 COMPUT SECUR JI Comput. Secur. PD OCT PY 2005 VL 24 IS 7 BP 561 EP 570 DI 10.1016/j.cose.2005.07.001 PG 10 WC Computer Science, Information Systems SC Computer Science GA 983LF UT WOS:000233232400018 ER PT J AU Newton, RL Davidson, JL Ice, GE Liu, W AF Newton, RL Davidson, JL Ice, GE Liu, W TI Synchrotron X-ray microdiffraction analysis of proton irradiated polycrystalline diamond films SO DIAMOND AND RELATED MATERIALS LA English DT Article DE diamond films; microdiffraction; synchrotron radiation; Microelectromechanical Systems (MEMS) ID RESIDUAL-STRESS; RAMAN; DIFFRACTION AB X-ray microdiffraction is a non-destructive technique that allows for depth-resolved, strain measurements with submicron spatial resolution. These capabilities make this technique promising for understanding the mechanical properties of MicroElectroMechancial Systems (MEMS). This investigation examined the local strain induced by irradiating a polycrystalline diamond thin film with a dose of 2 x 10(17) H+/cm(2) protons. Preliminary results indicate that a measurable strain, on the order of 10(-3), was introduced into the film near the End of Range (EOR) region of the protons. Published by Elsevier B.V. C1 NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. Vanderbilt Univ, Nashville, TN USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Newton, RL (reprint author), NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. EM robby.newton@nasa.gov NR 9 TC 0 Z9 1 U1 1 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-9635 J9 DIAM RELAT MATER JI Diam. Relat. Mat. PD OCT PY 2005 VL 14 IS 10 BP 1588 EP 1591 DI 10.1016/j.diamond.2005.03.009 PG 4 WC Materials Science, Multidisciplinary SC Materials Science GA 967DH UT WOS:000232071200003 ER PT J AU Rozas, LP Minello, TJ Munuera-Fernandez, I Fry, B Wissel, B AF Rozas, LP Minello, TJ Munuera-Fernandez, I Fry, B Wissel, B TI Macrofaunal distributions and habitat change following winter-spring releases of freshwater into the Breton Sound estuary, Louisiana (USA) SO ESTUARINE COASTAL AND SHELF SCIENCE LA English DT Article DE river diversion; brown shrimp; Farfantepenaeus aztecus; salinity; restoration; SAV; submerged aquatic vegetation ID SHRIMP FARFANTEPENAEUS-AZTECUS; PENAEUS-AZTECUS; BROWN SHRIMP; SALT-MARSH; DECAPOD CRUSTACEANS; NEKTON USE; CALLINECTES-SAPIDUS; ABUNDANCE PATTERNS; NITROGEN ISOTOPES; STABLE-ISOTOPES AB We examined the effect of freshwater inflows on the aquatic environment and macrofauna in the intermediate and brackish zones of the Breton Sound estuary. Following water releases from the Caernarvon Freshwater Diversion Structure in winter 2000 and spring 2001, we compared environmental conditions and the abundance and distribution of nekton in May 2001 between the inflow area, which receives freshwater directly from the structure, and a nearby reference area. We used these data and stable isotope analyses for C, N, and S in brown shrimp Farfantepenaeus aztecus and two species of grass shrimp (Palaemonetes paludosus and Palaemonetes intermedius) to test four null hypotheses: (1) water quality and SAV (submerged aquatic vegetation) coverage were similar between the inflow and reference areas, (2) macrofaunal abundance and biomass were similar between the two areas, (3) stable isotopic values of brown shrimp and grass shrimp were similar between areas, habitat types, and species, and (4) brown shrimp distributions were unaffected by river inputs. Freshwater from the structure clearly influenced the estuarine environment within the inflow area. Releases from the Caernarvon structure freshened the inflow area as intended and increased SAV and daytime dissolved oxygen concentrations. The response by macrofauna to these increased freshwater flows and habitat changes involved mostly changes in density and biomass rather than shifts in species composition. Although we detected no strong effect of the freshwater diversion on brown shrimp abundance or size in the inflow area, results of the sulfur stable isotope analysis indicated that brown shrimp collected in the inflow area had been growing in higher salinity waters, possibly following downstream displacement by the diversion. Species that would benefit most from continued freshwater diversions are likely to be those species that both use SAV as nursery habitat and thrive in a low-salinity environment. Nutrients carried by water from the structure were incorporated into the estuarine food web, and these nutrient inputs, together with an increase in SAV habitat, may enhance overall secondary productivity in the inflow area. (c) 2005 Elsevier Ltd. All rights reserved. C1 NOAA, Natl Marine Fisheries Serv, SEFSC, Fishery Ecol Branch,Estuarine Habitats & Coastal, Lafayette, LA 70506 USA. NOAA, Natl Marine Fisheries Serv, SEFSC, Galveston Lab, Galveston, TX 77551 USA. Univ Oviedo, Dept Biol Organismos & Sistemas, E-33071 Oviedo, Spain. Louisiana State Univ, Dept Oceanog & Coastal Sci, Coastal Ecol Inst, Baton Rouge, LA 70803 USA. RP NOAA, Natl Marine Fisheries Serv, SEFSC, Fishery Ecol Branch,Estuarine Habitats & Coastal, 646 Cajundome Blvd,Suite 175, Lafayette, LA 70506 USA. EM lawrence.rozas@noaa.gov NR 69 TC 28 Z9 28 U1 1 U2 19 PU ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0272-7714 EI 1096-0015 J9 ESTUAR COAST SHELF S JI Estuar. Coast. Shelf Sci. PD OCT PY 2005 VL 65 IS 1-2 BP 319 EP 336 DI 10.1016/j.eess.2005.05.019 PG 18 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA 975EL UT WOS:000232643700027 ER PT J AU Mulavara, AP Richards, JT Ruttley, T Marshburn, A Nomura, Y Bloomberg, JJ AF Mulavara, AP Richards, JT Ruttley, T Marshburn, A Nomura, Y Bloomberg, JJ TI Exposure to a rotating virtual environment during treadmill locomotion causes adaptation in heading direction SO EXPERIMENTAL BRAIN RESEARCH LA English DT Article ID VENTRAL INTRAPARIETAL AREA; PODOKINETIC AFTER-ROTATION; SELF-MOTION PERCEPTION; OPTIC FLOW; STEPPING TEST; WALKING; STIMULATION; VISION; TRUNK; MST AB The objective of this study was to investigate the adaptive effects of variation in the direction of optic flow, experienced during linear treadmill walking, on modifying locomotor trajectory. Subjects (n=30) walked on a motorized linear treadmill at 4.0 km h(-1) for 24 min while viewing the interior of a 3D virtual scene projected on to a screen 1.5 m in front of them. The virtual scene depicted constant self-motion equivalent to either (1) walking around the perimeter of a room to one's left (Rotating Room group) or (2) walking down the center of a hallway (Infinite Corridor group). The scene was static for the first 4 min and then constant rate self-motion was simulated for the remaining 20 min. Before and after the treadmill locomotion adaptation period subjects performed five stepping trials. In each trial they marched in place to the beat of a metronome at 90 steps min(-1) for a total of 100 steps while blindfolded in a quiet room. The subject's final heading direction (deg) and final X (fore-aft, cm) and final Y (medio-lateral, cm) positions were measured for each trial. During the treadmill locomotion adaptation period subjects' 3D torso position was measured. We found that subjects in the Rotating Room group, as compared with the Infinite Hallway group: (1) showed significantly greater deviation during post-exposure testing in the heading direction and Y position opposite to the direction of optic flow experienced during treadmill walking; and (2) showed a significant monotonically increasing torso yaw angular rotation bias in the direction of optic flow during the treadmill adaptation exposure period. Subjects in both groups showed greater forward translation (in the +X direction) during the post-treadmill stepping task that differed significantly from their pre-exposure performance. Subjects in both groups reported no perceptual deviation in position during the stepping tasks. We infer that viewing simulated rotary self-motion during treadmill locomotion causes adaptive modification of sensorimotor integration in the control of position and trajectory during locomotion, which functionally reflects adaptive changes in the integration of visual, vestibular, and proprioceptive cues. Such an adaptation in the control of position and heading direction during locomotion, because of the congruence of sensory information, demonstrates the potential for adaptive transfer between sensorimotor systems and suggests a common neural site for processing and self-motion perception and concurrent adaptation in motor output. C1 Natl Space Biomed Res Inst, Baylor Coll Med, Neurosci Lab, Houston, TX 77058 USA. Wyle Life Sci Inc, Houston, TX 77058 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Nihon Univ, Sch Med, Tokyo 1738610, Japan. RP Mulavara, AP (reprint author), Natl Space Biomed Res Inst, Baylor Coll Med, Neurosci Lab, 2101 NASA Pkwy, Houston, TX 77058 USA. EM ajitkumar.mulavara1@jsc.nasa.gov RI Ruttley, Tara/D-8696-2016 OI Ruttley, Tara/0000-0001-7184-6749 NR 47 TC 16 Z9 16 U1 1 U2 2 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 0014-4819 J9 EXP BRAIN RES JI Exp. Brain Res. PD OCT PY 2005 VL 166 IS 2 BP 210 EP 219 DI 10.1007/s00221-005-2356-0 PG 10 WC Neurosciences SC Neurosciences & Neurology GA 968KW UT WOS:000232162400007 PM 16034569 ER PT J AU Wernet, MP Van Zante, D Strazisar, TJ John, WT Prahst, PS AF Wernet, MP Van Zante, D Strazisar, TJ John, WT Prahst, PS TI Characterization of the tip clearance flow in an axial compressor using 3-D digital PIV SO EXPERIMENTS IN FLUIDS LA English DT Article AB The accurate characterization and simulation of rotor tip clearance flows has received much attention in recent years due to their impact on compressor performance and stability. At NASA Glenn the first known three dimensional digital particle image velocimetry (DPIV) measurements of the tip region of a low speed compressor rotor have been acquired to characterize the behavior of the rotor tip clearance flow. The measurements were acquired phase-locked to the rotor position so that changes in the tip clearance vortex position relative to the rotor blade can be seen. The DPIV technique allows the magnitude and relative contributions of both the asynchronous motions of a coherent structure and the temporal unsteadiness to be evaluated. Comparison of measurements taken at the peak efficiency and at near stall operating conditions characterizes the mean position of the clearance vortex and the changes in the unsteady behavior of the vortex with blade loading. Comparisons of the 3-D DPIV measurements at the compressor design point to a 3D steady N-S solution are also done to assess the fidelity of steady, single-passage simulations to model an unsteady flow field. C1 NASA, Glenn Res Ctr Lewis Field, Cleveland, OH 44135 USA. Ohio Aerosp Inst, Brookpark, OH 44142 USA. AP Solut, Cleveland, OH 44135 USA. RP Wernet, MP (reprint author), NASA, Glenn Res Ctr Lewis Field, MS-77-1,21000 Brookpk Rd, Cleveland, OH 44135 USA. EM mark.p.wernet@nasa.gov NR 10 TC 19 Z9 23 U1 2 U2 8 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 0723-4864 J9 EXP FLUIDS JI Exp. Fluids PD OCT PY 2005 VL 39 IS 4 BP 743 EP 753 DI 10.1007/s00348-005-0007-7 PG 11 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA 992VW UT WOS:000233913100011 ER PT J AU Lanoil, BD La Duc, MT Wright, M Kastner, M Nealson, KH Bartlett, D AF Lanoil, BD La Duc, MT Wright, M Kastner, M Nealson, KH Bartlett, D TI Archaeal diversity in ODP legacy borehole 892b and associated seawater and sediments of the Cascadia Margin SO FEMS MICROBIOLOGY ECOLOGY LA English DT Article DE Cascadia Margin; Archaea; 16S rRNA; Ocean Drilling Project (ODP) ID ANAEROBIC METHANE OXIDATION; DEEP-SEA SEDIMENTS; GAS HYDRATE; SUBDUCTION ZONE; PHYLOGENETIC ANALYSIS; MICROBIAL DIVERSITY; AUTHIGENIC CARBONATES; MASSIVE DISSOCIATION; ACCRETIONARY PRISM; LATEST PALEOCENE AB The Cascadia Margin is a region of active accretionary tectonics characterized by high methane flux accompanied by the formation of sedimentary gas hydrates, carbonate nodules, and carbonate pavements. Several sediment cores have been obtained from this region by the Ocean Drilling Project (ODP), and in some cases the boreholes have been sealed off, serving as sites for long-term observatories. We characterized geochemical parameters and diversity of Archaea in one such "legacy" borehole, ODP site 892b, as well as in bottom water immediately above the borehole and in two nearby sediments. The methane concentrations in the samples varied over five orders of magnitude, from approximate to 25 to 35 nM in the bottom water to approximate to 1.4 mM in one of the sediment samples. Despite these differences, the Archaeal community in all samples was dominated by gene sequences related to the methanogenic Archaea, a finding that correlates with studies of other environments characterized by high methane flux. The archaeal phylotype richness in borehole ODP 892b was limited to two phylotypes; one specifically related to Methanosaeta spp., the other to the anaerobic methane oxidizing ANME-1 group. Although some similar groups were observed in nearby sediment and seawater samples, their archaeal phylotype richness was significantly higher than in the borehole. The possible presence of a dynamic microbial community in the Cascadia Margin sub-surface and its potential roles in methanogenesis, anaerobic oxidation of methane, and authigenic precipitation of carbonate in the Cascadia Margin are discussed. (C) 2005 Federation of European Microbiological Societies. Published by Elsevier B.V. All rights reserved. C1 Univ Calif Riverside, Dept Environm Sci, Riverside, CA 92521 USA. NASA, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Calif San Diego, Scripps Inst Oceanog, Div Marine Biol Res, La Jolla, CA 92093 USA. Univ Calif San Diego, Scripps Inst Oceanog, Geosci Res Div, La Jolla, CA 92093 USA. RP Lanoil, BD (reprint author), Univ Calif Riverside, Dept Environm Sci, Geol 2217, Riverside, CA 92521 USA. EM brian.lanoil@ucr.edu OI Lanoil, Brian/0000-0001-8603-8330 NR 65 TC 16 Z9 17 U1 0 U2 11 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-6496 J9 FEMS MICROBIOL ECOL JI FEMS Microbiol. Ecol. PD OCT 1 PY 2005 VL 54 IS 2 BP 167 EP 177 DI 10.1016/j.femsec.2005.03.015 PG 11 WC Microbiology SC Microbiology GA 972BF UT WOS:000232428100001 PM 16332316 ER PT J AU Yanagimoto, T Humphreys, RL AF Yanagimoto, T Humphreys, RL TI Maturation and reproductive cycle of female armorhead Pseudopentaceros wheeleri from the southern Emperor-northern Hawaiian Ridge Seamounts SO FISHERIES SCIENCE LA English DT Article DE armorhead; gonadal somatic index; histology; ovarian development; ovary; reproductive cycle; spawning season AB The stage of ovarian development and annual reproductive cycle of female armorhead Pseudopentaceros wheeleri collected from seamounts of the southern Emperor-northern Hawaiian Ridge in 1993 and 1995-1996 was investigated through use of the gonadal somatic index (GSI) and ovarian histology. The stages of oocyte development were classified into eight developmental stages (perinucleolus, cortical alveolus, oil droplet, early yolk globule, late yolk globule, migratory nucleolus, prematuration, and maturation) based on histological characteristics. Oocytes of different size and developmental stage were present within ovaries during the spawning season. Oocyte development appears to be asynchronous and armorhead apparently spawn several times during the spawning season. The stage of the most developed oocyte was used to classify the stage of ovarian maturation. The GSI increased gradually with ovarian development. Oocytes in the perinucleolus, cortical alveolus, and oil droplet stages were present in ovaries throughout the year. Early and late yolk globule stages appeared during August-September indicating that yolk formation begins during late summer. The migratory nucleolus through maturation stages were detected during November-January. Post ovulatory follicles were present during November-March, and GSI values rapidly decreased in February. Results indicate that spawning occurs during November-February and peaks during December-January. C1 Hokkaido Natl Fisheries Res Inst, Kushiro, Hokkaido 0850802, Japan. NOAA, Natl Marine Fisheries Serv, SW Fisheries Sci Ctr, Honolulu Lab, Honolulu, HI 96822 USA. RP Yanagimoto, T (reprint author), Hokkaido Natl Fisheries Res Inst, Kushiro, Hokkaido 0850802, Japan. EM yanagimo@fra.affrc.go.jp NR 30 TC 7 Z9 7 U1 2 U2 2 PU JAPANESE SOC FISHERIES SCIENCE PI TOKYO PA C/O TOKYO UNIV FISHERIES, KONAN 4, MINATO, TOKYO, 108-8477, JAPAN SN 0919-9268 J9 FISHERIES SCI JI Fish. Sci. PD OCT PY 2005 VL 71 IS 5 BP 1059 EP 1068 DI 10.1111/j.1444-2906.2005.01064.x PG 10 WC Fisheries SC Fisheries GA 980XL UT WOS:000233051400014 ER PT J AU Crumpler, LS Squyres, SW Arvidson, RE Bell, JF Blaney, D Cabrol, NA Christensen, PR DesMarais, DJ Farmer, JD Fergason, R Golombek, MP Grant, FD Grant, JA Greeley, R Hahn, B Herkenhoff, KE Hurowitz, JA Knudson, AT Landis, GA Li, R Maki, J McSween, HY Ming, DW Moersch, JE Payne, MC Rice, JW Richter, L Ruff, SW Sims, M Thompson, SD Tosca, N Wang, A Whelley, P Wright, SP Wyatt, MB AF Crumpler, LS Squyres, SW Arvidson, RE Bell, JF Blaney, D Cabrol, NA Christensen, PR DesMarais, DJ Farmer, JD Fergason, R Golombek, MP Grant, FD Grant, JA Greeley, R Hahn, B Herkenhoff, KE Hurowitz, JA Knudson, AT Landis, GA Li, R Maki, J McSween, HY Ming, DW Moersch, JE Payne, MC Rice, JW Richter, L Ruff, SW Sims, M Thompson, SD Tosca, N Wang, A Whelley, P Wright, SP Wyatt, MB TI Mars Exploration Rover Geologic traverse by the Spirit rover in the Plains of Gusev Crater, Mars SO GEOLOGY LA English DT Article DE Mars; planetary geology; rover; geotraverse; field geology ID SPECTROMETER; ROCKS AB The Spirit rover completed a 2.5 km traverse across gently sloping plains on the floor of Gusev crater from its location on the outer rim of Bonneville crater to the lower slopes of the Columbia Hills, Mars. Using the Athena suite of instruments in a transect approach, a systematic series of overlapping panoramic mosaics, remote sensing observations, surface analyses, and trenching operations documented the lateral variations in landforms, geologic materials, and chemistry of the surface throughout the traverse, demonstrating the ability to apply the techniques of field geology by remote rover operations. Textures and shapes of rocks within the plains are consistent with derivation from impact excavation and mixing of the upper few meters of basaltic lavas. The contact between surrounding plains and crater ejecta is generally abrupt and marked by increases in clast abundance and decimeter-scale steps in relief. Basaltic materials of the plains overlie less indurated and more altered rock types at a time-stratigraphic contact between the plains and Columbia Hills that occurs over a distance of one to two meters. This implies that regional geologic contacts are well preserved and that Earth-like field geologic mapping will be possible on Mars despite eons of overturn by small impacts. C1 New Mexico Museum Nat Hist & Sci, Albuquerque, NM 87104 USA. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. Washington Univ, Dept Earth & Planetary Sci, St Louis, MO 63130 USA. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. NASA, SETI, Div Space Sci, Moffett Field, CA 94035 USA. Arizona State Univ, Dept Geol Sci, Tempe, AZ 85287 USA. Smithsonian Inst, Natl Air & Space Museum, Ctr Earth & Planetary Studies, Washington, DC 20560 USA. SUNY Stony Brook, Dept Geosci, Stony Brook, NY 11794 USA. US Geol Survey, Flagstaff, AZ 86001 USA. SUNY Stony Brook, Dept Geosci, Stony Brook, NY 11794 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. Ohio State Univ, Dept Civil & Environm Engn, Columbus, OH 43210 USA. Univ Tennessee, Dept Earth & Planetary Sci, Knoxville, TN 37996 USA. NASA, Johnson Space Ctr, Houston, TX USA. Inst Space Simulat, DLR, Cologne, Germany. RP Crumpler, LS (reprint author), New Mexico Museum Nat Hist & Sci, Albuquerque, NM 87104 USA. RI Hurowitz, Joel/A-8862-2008; Moersch, Jeffrey/F-7189-2010; Whelley, Patrick/B-9560-2012 OI Whelley, Patrick/0000-0003-3266-9772 NR 21 TC 22 Z9 23 U1 1 U2 5 PU GEOLOGICAL SOC AMERICA, INC PI BOULDER PA PO BOX 9140, BOULDER, CO 80301-9140 USA SN 0091-7613 J9 GEOLOGY JI Geology PD OCT PY 2005 VL 33 IS 10 BP 809 EP 812 DI 10.1130/G21673.1 PG 4 WC Geology SC Geology GA 969RM UT WOS:000232252400013 ER PT J AU Buccello, R Cromwell, R Bloomberg, J AF Buccello, R Cromwell, R Bloomberg, J TI The effects of sensorimotor adaptation training on functional mobility in older adults SO GERONTOLOGIST LA English DT Meeting Abstract C1 Univ Texas, Med Branch, Galveston, TX 77550 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU GERONTOLOGICAL SOCIETY AMER PI WASHINGTON PA 1275 K STREET NW SUITE 350, WASHINGTON, DC 20005-4006 USA SN 0016-9013 J9 GERONTOLOGIST JI Gerontologist PD OCT PY 2005 VL 45 SI 2 BP 517 EP 517 PG 1 WC Gerontology SC Geriatrics & Gerontology GA 988QF UT WOS:000233615001478 ER PT J AU Ichii, K Hashimoto, H Nemani, R White, M AF Ichii, K Hashimoto, H Nemani, R White, M TI Modeling the interannual variability and trends in gross and net primary productivity of tropical forests from 1982 to 1999 SO GLOBAL AND PLANETARY CHANGE LA English DT Article DE carbon cycle; tropical forest; terrestrial ecosystem; net primary productivity; gross primary productivity; climate change ID ATMOSPHERIC CARBON-DIOXIDE; TERRESTRIAL ECOSYSTEMS; AMAZONIAN FOREST; CLIMATE-CHANGE; CO2; TREE; BIOSPHERE; BALANCE; FLUXES; GROWTH AB The role of tropical ecosystems in global carbon cycling is uncertain, at least partially due to an incomplete understanding of climatic forcings of carbon fluxes. To reduce this uncertainty, we simulated and analyzed 1982-1999 Amazonian, African, and Asian carbon fluxes using the Biome-BGC prognostic carbon cycle model driven by National Centers for Environmental Prediction reanalysis daily climate data. We first characterized the individual contribution of temperature, precipitation, radiation, and vapor pressure deficit to interannual variations in carbon fluxes and then calculated trends in gross primary productivity (GPP) and net primary productivity (NPP). In tropical ecosystems, variations in solar radiation and, to a lesser extent, temperature and precipitation, explained most interannual variation in GPP. On the other hand, temperature followed by solar radiation primarily determined variation in NPP. Tropical GPP gradually increased in response to increasing atmospheric CO2. Confirming earlier studies, changes in solar radiation played a dominant role in CO2 uptake over the Amazon relative to other tropical regions. Model results showed negligible impacts from variations and trends in precipitation or vapor pressure deficits on CO2 uptake. (c) 2005 Elsevier B.V. All rights reserved. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. San Jose State Univ, San Jose, CA 95192 USA. Tokai Univ, Grad Sch Agr & Life Sci, Tokyo, Japan. Utah State Univ, Logan, UT 84322 USA. RP Ichii, K (reprint author), NASA, Ames Res Ctr, Mail Stop 242-4, Moffett Field, CA 94035 USA. EM kichii@arc.nasa.gov RI Ichii, Kazuhito/D-2392-2010; OI Ichii, Kazuhito/0000-0002-8696-8084; White, Michael/0000-0002-0238-8913 NR 50 TC 34 Z9 37 U1 3 U2 18 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-8181 J9 GLOBAL PLANET CHANGE JI Glob. Planet. Change PD OCT PY 2005 VL 48 IS 4 BP 274 EP 286 DI 10.1016/j.gloplacha.2005.02.005 PG 13 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA 978AR UT WOS:000232845100002 ER PT J AU Lombard, A Cazenave, A DoMinh, K Cabanes, C Nerem, RS AF Lombard, A Cazenave, A DoMinh, K Cabanes, C Nerem, RS TI Thermosteric sea level rise for the past 50 years; comparison with tide gauges and inference on water mass contribution SO GLOBAL AND PLANETARY CHANGE LA English DT Article DE sea level rise; global change; ocean warming; eustatic sea level AB In this paper we compare sea level trends observed at a few selected tide gauges of good quality records with thermosteric (i.e., due to ocean temperature change) sea level trends over 1950-1998 using different gridded ocean temperature data sets from Levitus et al. (2000) [Levitus, S., Stephens, C., Antonov, J.I., Boyer, T.P., 2000. Yearly and Year-Season Upper Ocean Temperature Anomaly Fields, 1948-1998. U.S. Gov. Printing Office, Washington, D.C. pp. 23.], Ishii et al. (2003) [Ishii, M., Kimoto, M., Kachi, M., 2003. Historical ocean subsurface temperature analysis with error estimates, Mon. Weather Rev., 13 1, 51-73.] and Levitus et al. (2005) [Levitus S., Antonov, J.I., Boyer, T.P., 2005. Warming of the world ocean, 1955-2003. Geophys. Res. Lett. 32, L02604. doi:10.1029/2004GL021592.]. When using the Levitus data, we observe very high thermosteric rates at sites located along the northeast coast of the US, north of 37 degrees N. Such high rates are not observed with the Ishii data. Elsewhere, thermosteric rates agree reasonably well whatever the data set. Excluding the northeast US coastline sites north of 37 degrees N, we compare tide gauge-based sea level trends with thermosteric trends and note that, in spite of a significant correlation, the latter are too small to explain the observed trends. After correcting for thermosteric sea level trends, residual (observed minus thermosteric) trends have an average value of 1.4 +/- 0.5 mm/year, which should have an eustatic (i.e., due to ocean mass change) origin. This result supports the recent investigation by Miller and Douglas (2004) [Miller, L., Douglas, B.C., 2004. Mass and volume contributions to 20th century global sea level rise. Nature 428, 406-408.] which suggests that a dominant eustatic contribution is needed to explain the rate of sea level rise of the last decades observed by tide gauges, and shows that Cabanes et al. (2001) [Cabanes, C., Cazenave, A., Le Provost, C., 2001. Sea level rise during past 40 years determined from satellite and in situ observations. Science 294, 840-842.] arrived at an incorrect conclusion due to peculiarities in the gridded Levitus et al. (2000) [Levitus, S., Stephens, C., Antonov, J.I., and Boyer, T.P., 2000. Yearly and Year-Season Upper Ocean Temperature Anomaly Fields, 1948-1998. U.S. Gov. Printing Office, Washington, D.C. pp. 23.] data set. (c) 2005 Elsevier B.V. All rights reserved. C1 CNES, LEGOS, Toulouse, France. JPL, Pasadena, CA USA. Univ Colorado, CCAR, Boulder, CO 80309 USA. RP Lombard, A (reprint author), CNES, LEGOS, 18 Av E Belin, Toulouse, France. EM lombard@notos.cst.cnes.fr NR 26 TC 20 Z9 23 U1 0 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-8181 J9 GLOBAL PLANET CHANGE JI Glob. Planet. Change PD OCT PY 2005 VL 48 IS 4 BP 303 EP 312 DI 10.1016/j.gloplacha.2005.02.007 PG 10 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA 978AR UT WOS:000232845100004 ER PT J AU Johnson, L Scholasch, T AF Johnson, L Scholasch, T TI Remote sensing of shaded area in vineyards SO HORTTECHNOLOGY LA English DT Editorial Material DE grape; NDVI; transpiration; irrigation; crop coefficient; Vitis vinifera ID SPECTRAL REFLECTANCE; CROP COEFFICIENTS; INDEX; MANAGEMENT; RADIATION; QUALITY AB Airborne: multispectral image data were compared with intercepted photosynthetic photon flux (PPF) in commercial winegrape (Vitis vinifera) vineyards of Napa Valley, Calif. An empirically based calibration was applied to transform raw image pixel values to surface reflectance. Reflectance data from the red and near-infrared spectral regions were combined into a normalized difference vegetation index. Strong linear response was observed between the vegetation index and PPF interception ranging from 0.15 to 0.50. Study results suggest the possibility of using optical remote sensing to monitor and map vineyard shaded area, thus providing spatially explicit input to water budget models that invoke evapotranspiration crop coefficient based calculations. C1 NASA, Ames Res Ctr, Div Earth Sci, Moffett Field, CA 94035 USA. RP NASA, Ames Res Ctr, Div Earth Sci, 242-4, Moffett Field, CA 94035 USA. EM ljohnson@mail.arc.nasa.gov NR 31 TC 11 Z9 11 U1 1 U2 7 PU AMER SOC HORTICULTURAL SCIENCE PI ALEXANDRIA PA 113 S WEST ST, STE 200, ALEXANDRIA, VA 22314-2851 USA SN 1063-0198 EI 1943-7714 J9 HORTTECHNOLOGY JI HortTechnology PD OCT-DEC PY 2005 VL 15 IS 4 BP 859 EP 863 PG 5 WC Horticulture SC Agriculture GA 970NT UT WOS:000232317600022 ER PT J AU Lee, S Pappalardo, RT Makris, NC AF Lee, S Pappalardo, RT Makris, NC TI Mechanics of tidally driven fractures in Europa's ice shell SO ICARUS LA English DT Article; Proceedings Paper CT Workshop on Europas Icy Shell CY FEB 06-08, 2004 CL Lunar & Planetary Inst, Houston, TX HO Lunar & Planetary Inst DE Europa; ices; porosity; tides; ocean; fracture; cycloid; radar ID GALILEAN SATELLITES; SUBSURFACE OCEAN; CALLISTO; GANYMEDE; FEATURES; ARECIBO; GEOLOGY AB A fracture mechanics model is developed for the initiation and propagation of a crack through a porous ice layer of finite thickness under gravitational overburden. It is found that surface cracks generated in response to a tidally induced stress field may penetrate through the entire outer brittle layer if a subsurface ocean is present on Europa. Such penetration is found to be very unlikely in the absence of an ocean. A cycloidal crack would then form as a sequence of near instantaneous discrete failures, each extending roughly the brittle layer thickness in range, linked with a much lower apparent propagation speed set by the moving tidal stress field. The implications of this porous ice fracture model for ice-penetrating radar scattering loss and seismic activity are quantified. (c) 2005 Elsevier Inc. All rights reserved. C1 MIT, Dept Mech Engn, Cambridge, MA 02139 USA. Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80309 USA. Univ Colorado, NASA, Astrobiol Inst, Boulder, CO 80309 USA. RP Makris, NC (reprint author), MIT, Dept Mech Engn, 77 Massachusetts Ave, Cambridge, MA 02139 USA. EM makris@mit.edu NR 60 TC 20 Z9 20 U1 2 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 J9 ICARUS JI Icarus PD OCT PY 2005 VL 177 IS 2 BP 367 EP 379 DI 10.1016/j.icarus.2005.07.003 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 974FQ UT WOS:000232577100006 ER PT J AU Carlson, RW Anderson, MS Mehlman, R Johnson, RE AF Carlson, RW Anderson, MS Mehlman, R Johnson, RE TI Distribution of hydrate on Europa: Further evidence for sulfuric acid hydrate SO ICARUS LA English DT Article; Proceedings Paper CT Workshop on Europas Icy Shell CY FEB 06-08, 2004 CL Lunar & Planetary Inst, Houston, TX HO Lunar & Planetary Inst DE surfaces; satellites; Europa; radiation chemistry; spectroscopy; radiative transfer ID INFRARED MAPPING SPECTROMETER; GALILEAN SATELLITES; LOW-TEMPERATURES; CRATERING RATES; WATER ICE; SURFACE; ALBEDO; MODEL; UV; SPECTROSCOPY AB Sulfuric acid hydrate has been proposed as an important species on Europa's surface, the acid being produced by radiolysis of surficial sulfur compounds. We investigated the spectral properties of disordered and crystalline forms of sulfuric acid and suggest that the hydration properties of Europa's hypothesized sulfuric acid lie between two end members: liquid sulfuric acid and its higher crystalline hydrates. The spectra of these end members are similar except for spectral shifts at the band edges. We measured the optical constants of sulfuric acid octahydrate and used these with simple radiative transfer calculations to fit Europa spectra obtained by Galileo's Near Infrared Mapping Spectrometer (NIMS). The global distribution of the hydrate that we associate here with hydrated sulfuric acid shows a strong trailing-side enhancement with a maximum fractional hydrate abundance of 90% by volume, corresponding to a sulfur atom to water molecule ratio of 10%. The hydrate concentration spatially correlates with the ultraviolet and visible absorption of the surface and with the sulfur dioxide concentration. The asymmetric global distribution is consistent with Iogenic plasma ion implantation as the source of the sulfur, possibly modified by electron irradiation and sputtering effects. The variegated distribution also correlates with geologic forms. A high spatial resolution image shows resolved lineae with less hydrate appearing within the lineae than in nearby crustal material. The low concentration of hydrated material in these lineae argues against their conveying sulfurous material to the surface from the putative ocean. (c) 2005 Elsevier Inc. All rights reserved. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90024 USA. Univ Virginia, Charlottesville, VA USA. RP Carlson, RW (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM rcarlson@lively.jpl.nasa.gov NR 58 TC 51 Z9 51 U1 0 U2 21 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 OCT PY 2005 VL 177 IS 2 BP 461 EP 471 DI 10.1016/j.icarus.2005.03.026 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 974FQ UT WOS:000232577100013 ER PT J AU Dalton, JB Prieto-Ballesteros, O Kargel, JS Jamieson, CS Jolivet, J Quinn, R AF Dalton, JB Prieto-Ballesteros, O Kargel, JS Jamieson, CS Jolivet, J Quinn, R TI Spectral comparison of heavily hydrated salts with disrupted terrains on Europa SO ICARUS LA English DT Article; Proceedings Paper CT Workshop on Europas Icy Shell CY FEB 06-08, 2004 CL Lunar & Planetary Inst, Houston, TX HO Lunar & Planetary Inst DE Europa; experimental techniques; surfaces; satellite; spectroscopy ID ORIENTATIONALLY DISORDERED CRYSTALS; INFRARED MAPPING SPECTROMETER; ICY GALILEAN SATELLITES; 0.65-2.5 MU-M; WATER ICE; REFLECTANCE SPECTROSCOPY; SURFACE-COMPOSITION; SUBSURFACE OCEAN; ABSORPTION-BAND; OPTICAL SPECTRA AB Hydrated magnesium sulfate salts have been proposed as major components of the disrupted, reddish terrains on the surface of Europa. This is based on near-infrared reflectance spectra which contain distorted and asymmetric water absorption features typical of moderately hydrated materials such as hexahydrite (MgSO4 center dot 6H(2)O) and epsomite (MgSO4 center dot 7H(2)O). Hydrated magnesium sulfates having many waters of hydration could produce improved spectral matches. Here we present cryogenic laboratory spectra of highly hydrated sulfur-bearing salts, including hexahydrite, epsomite, bloedite (Na2Mg(SO4)(2)center dot 4H(2)O), mirabilite (Na2SO4 center dot 10H(2)O), sodium sulfide nonahydrate (Na2S center dot 9H(2)O), supersaturated MgSO4, NaHCO3, and Na2SO4 brines, and magnesium sulfate dodecahydrate (MgSO4 center dot 12H(2)O). All have been measured under conditions of pressure and temperature appropriate to the surface environment of Europa. Novel methods for preparation, verification and analysis of MgSO4 center dot 12H(2)O, which is not stable at standard temperature and pressure (STP), are described. At 100 K, all of these materials exhibit distorted and asymmetric absorption features similar to those in the Europa observations, as well as several weaker, narrow absorptions having widths ranging from 15 to 80 nm. While the agreement with Galileo NIMS observations of dark terrains on Europa is indeed better for highly hydrated salts than for salts of lower hydration states, we conclude that none of these materials alone can account for all of the observed spectral character. As previously suggested, Europa's reddish material appears to be a complex mixture of sulfate hydrates and other materials. (c) 2005 Elsevier Inc. All rights reserved. C1 NASA, Ames Res Ctr, SETI Inst, Moffett Field, CA 94035 USA. CSIC, Ctr Astrobiol, INTA, Madrid, Spain. US Geol Survey, Astrogeol Branch, Flagstaff, AZ 86001 USA. Univ Hawaii Manoa, Honolulu, HI 96822 USA. Texas So Univ, Houston, TX 77004 USA. SETI Inst, Moffett Field, CA 94035 USA. RP Dalton, JB (reprint author), NASA, Ames Res Ctr, SETI Inst, MS 245-3, Moffett Field, CA 94035 USA. EM dalton@mail.arc.nasa.gov NR 129 TC 80 Z9 80 U1 1 U2 20 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 OCT PY 2005 VL 177 IS 2 BP 472 EP 490 DI 10.1016/j.icarus.2005.02.023 PG 19 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 974FQ UT WOS:000232577100014 ER PT J AU Hwu, SU Loh, YC Dobbins, JA Kroll, QD Sham, CC AF Hwu, SU Loh, YC Dobbins, JA Kroll, QD Sham, CC TI Space shuttle UHF communications performance evaluation SO IEEE AEROSPACE AND ELECTRONIC SYSTEMS MAGAZINE LA English DT Article AB Computational investigations and experimental measurements were performed to evaluate the Space Shuffle UBF communication system performance for payload bay antenna at the proposed new location. To insure adequate communication coverage at relocated new location, the link margin for the Extravehicular Activity (EVA) astronauts and between Space Shuttle Orbiter and International Space Station (SSO-ISS) during rendezvous were analyzed. The multipath effects from the vehicle structures surrounding the antenna were investigated. The Radio Frequency (RF) electromagnetic radiation to the Orbiter Docking System (ODS) pyrotechnics was also analyzed to ensure the EMC/EMI compliances. C1 NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Hwu, SU (reprint author), Barrios Technol, Houston, TX 77058 USA. NR 6 TC 1 Z9 1 U1 1 U2 2 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 OCT PY 2005 VL 20 IS 10 BP 9 EP 14 DI 10.1109/MAES.2005.1581094 PG 6 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA 974QE UT WOS:000232605700002 ER PT J AU Im, E Wu, CL Durden, SL AF Im, E Wu, CL Durden, SL TI Cloud profiling radar for the CloudSat mission SO IEEE AEROSPACE AND ELECTRONIC SYSTEMS MAGAZINE LA English DT Article AB The Cloud Profiling Radar (CPR) for the upcoming CloudSat Mission is a spaceborne 94-GHz, nadir-looking radar that measures the power backscattered by clouds as a function of distance from the radar. This sensor is expected to provide cloud measurements at a 500-m vertical resolution and a 1.5km horizontal resolution. CPR will operate in a short-pulse mode and will yield measurements at a minimum detectable sensitivity of -28 dBZ. C1 Jet Propuls Lab, Pasadena, CA 91109 USA. RP Im, E (reprint author), Jet Propuls Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 4 TC 43 Z9 45 U1 3 U2 13 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 OCT PY 2005 VL 20 IS 10 BP 15 EP 18 DI 10.1109/MAES.2005.1581095 PG 4 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA 974QE UT WOS:000232605700003 ER PT J AU Gawronski, W Mellstrom, JA Bienkiewicz, B AF Gawronski, W Mellstrom, JA Bienkiewicz, B TI Antenna mean wind torques: A comparison of field and wind-tunnel data SO IEEE ANTENNAS AND PROPAGATION MAGAZINE LA English DT Article DE antennas; antenna mechanical factors; wind tunnels; wind; antenna measurements; reflector antenna mechanical factors AB Accurate information about the action of wind on antennas is required for the sizing of antenna motors and for reliable prediction of antenna pointing errors in windy weather. For these purposes, wind-tunnel data were obtained 40 years ago, using a scaled antenna model. However, their accuracy has been challenged, since they have not yet been verified in a field environment (i.e., for a full-sized antenna, with real wind instead of a steady air flow, and with the influences of the actual terrain, etc.). The purpose of this investigation was to obtain appropriate field measurements, compare them with the available wind-tunnel data, and verify the usefulness of the wind-tunnel data. For this purpose, we measured the steady-state (mean) wind torques of the NASA Deep Space Network 34-meter antenna, calculated the dimensionless wind torques for a variety of wind yaw angles and antenna elevation angles, and compared them with the wind-tunnel data. The results showed that the differences between the wind-tunnel torques and the field torques were less than 10%. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Colorado State Univ, Dept Civil Engn, Ft Collins, CO 80523 USA. RP Gawronski, W (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM wodek.k.gawronski@jpl.nasa.gov NR 8 TC 2 Z9 5 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1045-9243 EI 1558-4143 J9 IEEE ANTENN PROPAG M JI IEEE Antennas Propag. Mag. PD OCT PY 2005 VL 47 IS 5 BP 55 EP 59 DI 10.1109/MAP.2005.1599166 PG 5 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 012EP UT WOS:000235321300007 ER PT J AU Aspey, RA Brazier, KJ Spencer, JW AF Aspey, RA Brazier, KJ Spencer, JW TI Multiwavelength sensing of smoke using a polychromatic LED: Mie extinction characterization using HLS analysis SO IEEE SENSORS JOURNAL LA English DT Article DE aerosol; chromatic modulation; light-emitfing diode (LED); Mie; particulates; polychromatic; Rayleigh; scattering ID SOOT; SENSOR; SIZE AB A multiwavelength-sensing scheme using a polychromatic light-emitting diode has been developed for monitoring smoke to allow combustion material to be characterized. Spectral analysis uses HLS chromaticity parameterization to examine the interaction effects on the transmission of polychromatic light due to airborne aerosol/particles. The effects of wavelength and sample are investigated, and it is shown that, by using HLS analysis, it is possible to uniquely identify a combustion material by variations in lightness and saturation over a range of hue values. Lightness and saturation are shown to follow a distinct locus unique to the smoke from the combustion material, although the effect of fuel-oxygen mixing ratios have not been investigated and the data set is limited to two proof-of-concept case studies. The technique may, therefore, be applied to fire detection in inaccessible or remote areas (e.g., chemical plant, aircraft engines, etc.) where the type of response may be critical and dependent on combustion material. It may also potentially be used to identify liquids from their aerosol. C1 JPL Table Mt Facil, Wrightwood, CA 92397 USA. Univ E Anglia, Sch Comp & Informat Sci, Norwich NR4 7TJ, Norfolk, England. Univ Liverpool, Dept Elect Engn & Elect, Liverpool L69 3GJ, Merseyside, England. RP Aspey, RA (reprint author), Univ Durham, Dept Phys, Sci Labs, Durham DH1 3LE, England. EM robin.aspey@durham.ac.uk; kb@sys.uea.ac.uk; joe@liv.ac.uk NR 25 TC 3 Z9 3 U1 0 U2 8 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 OCT PY 2005 VL 5 IS 5 BP 1050 EP 1056 DI 10.1109/JSEN.2005.845207 PG 7 WC Engineering, Electrical & Electronic; Instruments & Instrumentation; Physics, Applied SC Engineering; Instruments & Instrumentation; Physics GA 962ZS UT WOS:000231772900037 ER PT J AU Cerf, VG Israel, D AF Cerf, VG Israel, D TI Networking SO IEEE SPECTRUM LA English DT Letter C1 NASA, Jet Propuls Lab, Pasadena, CA USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Cerf, VG (reprint author), NASA, Jet Propuls Lab, Pasadena, CA USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9235 J9 IEEE SPECTRUM JI IEEE Spectr. PD OCT PY 2005 VL 42 IS 10 BP 8 EP 8 PG 1 WC Engineering, Electrical & Electronic SC Engineering GA 972AB UT WOS:000232425100002 ER PT J AU Kenny, BH Jansen, R Kascak, P Dever, T Santiago, W AF Kenny, BH Jansen, R Kascak, P Dever, T Santiago, W TI Integrated power and attitude control with two flywheels SO IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS LA English DT Article; Proceedings Paper CT IEEE/AESS Aerospace Conference CY 2004 CL Big Sky, MT SP IEEE, AESS ID ENERGY-STORAGE AB Energy storage and attitude control are two distinct subsystems of the typical satellite. Energy storage is provided using batteries and active attitude control is accomplished with control moment gyroscopes or reaction wheels. A system mass savings can be achieved if these two subsystems are combined using multiple flywheels for simultaneous kinetic energy storage and momentum transfer. This paper develops, simulates, and experimentally demonstrates the control algorithms to accomplish integrated power and single-axis attitude control using two flywheels. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. Univ Toledo, Toledo, OH 43606 USA. RP Kenny, BH (reprint author), NASA, Glenn Res Ctr, MS 301-5,21000 Brookpk Rd, Cleveland, OH 44135 USA. EM Barbara.H.Kenny@grc.nasa.gov NR 24 TC 16 Z9 19 U1 1 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9251 J9 IEEE T AERO ELEC SYS JI IEEE Trans. Aerosp. Electron. Syst. PD OCT PY 2005 VL 41 IS 4 BP 1431 EP 1449 DI 10.1109/TAES.2005.1561894 PG 19 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 997GH UT WOS:000234232800015 ER PT J AU Yu, YY Privette, JL Pinheiro, AC AF Yu, YY Privette, JL Pinheiro, AC TI Analysis of the NPOESS VIIRS land surface temperature algorithm using MODIS data SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE land surface temperature (LST); Moderate Resolution Imaging Spectrometer (MODIS); National Polar Orbiting Environmental Sensor Suite (NPOESS); NPOESS Preparatory Project (NPP); split window (SW); Visible Infrared Imager Radiometer Sensor (VIIRS) ID HIGH-RESOLUTION RADIOMETER; EMISSIVITY; SPACE AB The Visible Infrared Imaging Radiometer Suite (VIIRS) will replace the National Oceanic and Atmospheric Administration's (NOAA) Advanced Very High Resolution Radiometer (AVHRR) and the National Aeronautics and Space Administration's (NASA) Moderate Resolution Imaging Spectrometer (MODIS) as the nation's wide-swath multispectral sensor following the launch of the. National Polar Orbiting Environmental Sensor Suite (NPOESS) Preparatory Project: (NPP) in about 2008. Through the follow-on NPOESS program, VIIRS data will be the primary source of systematic land remote sensing products until about 2022. Together, the AVHRR/MODIS/VIIRS satellite series will provide a critical long-term data record for Earth studies. In the NPP/NPOESS program, the product. algorithms and production environments are developed and managed by private industry. This is a significant change from the current NOAA and NASA programs, and NPOESS algorithm deviations from successful heritage approaches (e.g., Earth Observation System). warrant comprehensive independent testing. The current baseline VIIRS land surface temperature (LST) algorithm represents one such deviation. In the present study, we evaluated the VIIRS LST by adapting it for use with 60 scenes of MODIS Level 1b radiance data. Algorithm coefficients were derived from MODTRAN4 radiative transfer model simulations. Using the validated MODIS LST (MYD11_L2) product as a reference, we found that precision errors in the VIIRS dual split window (DSW) algorithm (the current "main" approach) significantly exceed those of the VIIRS split window (SW) algorithm (the current "backup" approach) in both daytime and nighttime conditions. Performance of both is better for nighttime cases than for daytime cases with all surface types. We attribute the larger errors in the DSW approach to its use of short middle infrared wavelengths which, compared to thermal infrared wavelengths, exhibit greater variability in surface emissivity and susceptibility to solar contamination. We conclude that a traditional SW algorithm, such as the current VIIRS backup algorithm, would provide superior performance to the DSW approach. An SW approach would also provide more seamless continuity with heritage products. Although this is not an NPOESS requirement, it is a key objective for multimission climate data records and Earth system data records. C1 George Mason Univ, Earth Syst & Geoinformat Sci Program, Fairfax, VA 22030 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Yu, YY (reprint author), George Mason Univ, Earth Syst & Geoinformat Sci Program, Fairfax, VA 22030 USA. EM yyu@pop900.gsfc.nasa.gov; jeff.privette@nasa.gov; ana@hsb.gsfc.nasa.gov RI Privette, Jeffrey/G-7807-2011; Yu, Yunyue/F-5636-2010 OI Privette, Jeffrey/0000-0001-8267-9894; NR 29 TC 30 Z9 30 U1 1 U2 8 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 OCT PY 2005 VL 43 IS 10 BP 2340 EP 2350 DI 10.1109/TGRS.2005.856114 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 968WE UT WOS:000232192800019 ER PT J AU Baginski, ME Faircloth, DL Deshpande, MD AF Baginski, ME Faircloth, DL Deshpande, MD TI Comparison of two optimization techniques for the estimation of complex permittivities of multilayered structures using waveguide measurements SO IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES LA English DT Article DE genetic algorithm (GA); multilayered substrate; permittivity extraction; sequential quadratic programming (SQP) ID MICROGENETIC ALGORITHM; DESIGN AB In this paper, two separate techniques, i.e., sequential quadratic programming (SQP) and a genetic algorithm (GA), were used to estimate the complex permittivity of each layer in a multilayer composite structure. The relative performance of the algorithms was characterized by applying each algorithm to one of three different error functions. Computer generated S-parameter data sets were initially used in order to establish the achievable accuracy of each algorithm. Based on these data sets and S-parameter measurements of single and multilayer samples obtained using a standard X-band waveguide procedure, the GA was determined to be the more robust algorithm in terms of minimizing rms error of measured/generated and formulated S-parameters. The GA was found to perform exceptionally well for all cases considered, whereas SQP, although a more computationally efficient method, was somewhat limited for two error function choices due to local minima trapping. C1 Auburn Univ, Dept Elect & Comp Engn, Auburn, AL 36849 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Baginski, ME (reprint author), Auburn Univ, Dept Elect & Comp Engn, Auburn, AL 36849 USA. NR 27 TC 19 Z9 19 U1 0 U2 2 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 OCT PY 2005 VL 53 IS 10 BP 3251 EP 3259 DI 10.1109/TMTT.2005.855133 PG 9 WC Engineering, Electrical & Electronic SC Engineering GA 974RB UT WOS:000232608000027 ER PT J AU Irom, F Farmanesh, FH AF Irom, F Farmanesh, FH TI Single-event upset in highly scaled commercial silicon-on-insulator PowerPC microprocessors SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 8th European Workshop on Radiation and Its Effects on Components and Systems CY SEP 19-23, 2004 CL Madrid, SPAIN DE cyclotron; heavy ion; microprocessors; silicon-on-insulator (SOI) ID SOI TECHNOLOGIES; IRRADIATION; BULK AB Single-event upset effects from heavy ions are measured for Motorola and IBM silicon-on-insulator (SOI) microprocessors with different feature sizes and core voltages. The results are compared with results for similar devices with bulk substrates. The cross sections of the SOI processors are lower than their bulk counterparts, but the threshold is about the same, even though the charge collections depth is more than an order of magnitude smaller in the SOI devices. The scaling of the cross section with reduction of feature size and core voltage dependence for SOI microprocessors is discussed. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Irom, F (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM farokh.irom@jpl.nasa.gov; farhad.f.farmanesh@jpl.nasa.gov NR 22 TC 4 Z9 4 U1 0 U2 1 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 OCT PY 2005 VL 52 IS 5 BP 1524 EP 1529 DI 10.1109/TNS.2005.855816 PN 2 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 990ZH UT WOS:000233781400013 ER PT J AU Fu, SJ Atiquzzaman, M Ivancic, W AF Fu, SJ Atiquzzaman, M Ivancic, W TI Evaluation of SCTP for space networks SO IEEE WIRELESS COMMUNICATIONS LA English DT Article AB The Stream Control Transmission Protocol has recently been standardized as a new transport layer protocol in the IP protocol suite. SCTP is based on the TCP protocol, but incorporates a number of advanced and unique features that are not available in TCP. Although the suitability of TCP over satellite networks has been widely studied, the suitability of SCTP over satellite networks remains to be evaluated. The objective of this article is to investigate the suitability of SCTP for data communications over satellite networks. We focus on the advanced features of SCTP that enhance its performance in satellite networks. Finally, we provide recommendations on the use of SCTP over satellite networks. C1 Univ Oklahoma, Sch Comp Sci, Norman, OK 73019 USA. NASA, Glenn Res Ctr, Cleveland, OH USA. EM atiq@ou.edu NR 15 TC 5 Z9 7 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 1536-1284 J9 IEEE WIREL COMMUN JI IEEE Wirel. Commun. PD OCT PY 2005 VL 12 IS 5 BP 54 EP 62 DI 10.1109/MWC.2005.1522105 PG 9 WC Computer Science, Hardware & Architecture; Computer Science, Information Systems; Engineering, Electrical & Electronic; Telecommunications SC Computer Science; Engineering; Telecommunications GA 978BB UT WOS:000232846100009 ER PT J AU Wilkhu, S Brown, JT AF Wilkhu, Sandeep Brown, James T. TI Cleared for liftoff SO INDUSTRIAL ENGINEER LA English DT Article C1 [Wilkhu, Sandeep] Kennedy Space Ctr Florida, IES Program, Orlando, FL 32815 USA. [Wilkhu, Sandeep] NASA, Washington, DC USA. [Wilkhu, Sandeep] Boeing Co, Seattle, WA 98124 USA. [Wilkhu, Sandeep] McDonnell Douglas Corp, Berkeley, MO USA. [Brown, James T.] SEBA Solut Inc, Viera, FL USA. RP Wilkhu, S (reprint author), Kennedy Space Ctr Florida, IES Program, Orlando, FL 32815 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU INST INDUSTRIAL ENGINEERS PI NORCROSS PA 3577 PARKWAY LANE, STE 200, NORCROSS, GA 30092 USA SN 1542-894X J9 IND ENG JI Ind. Eng PD OCT PY 2005 VL 37 IS 10 BP 42 EP 46 PG 5 WC Engineering, Industrial SC Engineering GA V18LK UT WOS:000208006100024 ER PT J AU Bandara, SV Gunapala, SD Liu, JK Rafol, SB Hill, CJ Ting, DZ Mumolo, JM Trinh, TQ AF Bandara, SV Gunapala, SD Liu, JK Rafol, SB Hill, CJ Ting, DZ Mumolo, JM Trinh, TQ TI Multi-band and broad-band infrared detectors based on III-V materials for spectral imaging instruments SO INFRARED PHYSICS & TECHNOLOGY LA English DT Article; Proceedings Paper CT 3rd International Workshop on Quantum Well Infrared Photodetectors CY AUG 09-12, 2004 CL Kananaskis, CANADA DE quantum-well infrared photodetector; multi-color; tunable detectors; thermal infrared ID FOCAL-PLANE ARRAY; LARGE-FORMAT; PHOTODETECTOR; INTERFEROMETERS AB Quantum well infrared photodetector technology has shown remarkable success by realizing large-format focal plane arrays in both broad-bands and in multi-bands. The spectral response of these detectors based on the III-V material system are tailorable within the mid and long wavelength IR bands (similar to 3-25 mu m) and possibly beyond. Multi-band and broad-band detector arrays have been developed by vertically integrating stacks of multi quantum wells tailored for response in different wavelengths bands. Each detector stack absorbs photons within the specified wavelength band while allowing the transmission other photons, thus efficiently permitting multiband detection. Flexibility in many design parameters of these detectors allows for tuning and tailoring the spectral shape according to application requirements, specifically for spectral imaging instruments. (c) 2005 Elsevier B.V. All rights reserved. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Bandara, SV (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM sumith.v.bandara@jpl.nasa.gov NR 14 TC 13 Z9 13 U1 1 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1350-4495 J9 INFRARED PHYS TECHN JI Infrared Phys. Technol. PD OCT PY 2005 VL 47 IS 1-2 BP 15 EP 21 DI 10.1016/j.infrared.2005.02.006 PG 7 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 968VJ UT WOS:000232190700004 ER PT J AU Gunapala, SD Bandara, SV Liu, JK Hill, CJ Rafol, SB Mumolo, JM Trinh, JT Tidrow, MZ LeVan, PD AF Gunapala, SD Bandara, SV Liu, JK Hill, CJ Rafol, SB Mumolo, JM Trinh, JT Tidrow, MZ LeVan, PD TI Development of mid-wavelength and long-wavelength megapixel portable QWIP imaging cameras SO INFRARED PHYSICS & TECHNOLOGY LA English DT Article; Proceedings Paper CT 3rd International Workshop on Quantum Well Infrared Photodetectors CY AUG 09-12, 2004 CL Kananaskis, CANADA DE QWIPs; mid-wavelength infrared; long-wavelength infrared; megapixel; infrared imaging camera ID WELL INFRARED DETECTORS; NARROW-BAND; BROAD-BAND AB Mid-wavelength infrared (MWIR) and long-wavelength infrared (LWIR) megapixel quantum well infrared photodetector (QWIP) focal plane arrays have been demonstrated with excellent imaging performance. The MWIR detector array has shown noise equivalent temperature difference (NETD) of 17 mK at 95 K operating temperature with f/2.5 optics at 300 K background and the LWIR detector array has given NETD of 13 m K at 70 K operating temperature with the same optical and background conditions as the MWIR array. Two portable prototype infrared cameras were fabricated using these two focal planes. The MWIR and the LWIR prototype cameras with similar optics have shown background limited performance (BLIP) at 90 K and 70 K operating temperatures respectively, at 300 K background. In this paper, we will discuss their performance in quantum efficiency, NETD, uniformity, and operability. (c) 2005 Elsevier B.V. All rights reserved. C1 CALTECH, Jet Prop Lab, Ctr Space Microelect Technol, Pasadena, CA 91109 USA. Missile Defense Agcy AS, Washington, DC 20301 USA. Kirtland AFB, AF Res Lab, Kirtland AFB, NM 87117 USA. RP Gunapala, SD (reprint author), CALTECH, Jet Prop Lab, Ctr Space Microelect Technol, 4800 Oak Grove Dr,M-S 302-306, Pasadena, CA 91109 USA. EM sarath.d.gunapala@jpl.nasa.gov NR 19 TC 14 Z9 14 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1350-4495 J9 INFRARED PHYS TECHN JI Infrared Phys. Technol. PD OCT PY 2005 VL 47 IS 1-2 BP 67 EP 75 DI 10.1016/j.infrared.2005.02.012 PG 9 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 968VJ UT WOS:000232190700011 ER PT J AU Choi, KK Monroy, C Goldberg, A Dang, G Jhabvala, M La, A Tamir, T Leung, KM Majumdar, A Li, JJ Tsui, DC AF Choi, KK Monroy, C Goldberg, A Dang, G Jhabvala, M La, A Tamir, T Leung, KM Majumdar, A Li, JJ Tsui, DC TI Designs and applications of corrugated QWIPs SO INFRARED PHYSICS & TECHNOLOGY LA English DT Article; Proceedings Paper CT 3rd International Workshop on Quantum Well Infrared Photodetectors CY AUG 09-12, 2004 CL Kananaskis, CANADA DE infrared detector; quantum well; light-coupling; FPA ID WELL INFRARED PHOTODETECTORS; DETECTION WAVELENGTH; SUPERLATTICES; PERFORMANCE AB In this paper, we will describe the performance of two long wavelength 1024 x 1024 corrugated quantum well infrared photodetector focal plane arrays (C-QWIP FPAs) with cutoff wavelengths at 8.6 and 9.0 mu m, respectively. The FPAs are background limited (BLIP) at around 76 Kin an f/1.8 optical system. In addition to the high performance of these C-QWIPs, the corresponding FPAs are also easily producible, making them ideal for large production. We will discuss the optimization of the detectors for different applications. Since corrugated coupling is wavelength insensitive, it is capable of broadband and multi-color detection. We will present a GaAs/AlGaAs broadband detector based on a binary superlattice design. Incorporating the broadband characteristic in a high gain InGaAs/InP material, C-QWIPs with large background photocurrent can be obtained for high speed applications. For multi-color detection, we have investigated two different approaches. One is based on a voltage-tunable, two-color QWIP material, which can be switched between two detection wavelengths simply by changing the detector bias. Stacking two of these similar QWIPs together and separating them with a middle contact layer, a voltage tunable, four-color detector array can be fabricated. A second approach is to combine a broadband QWIP material with a wavelength-selective light coupling method. Using a light coupling geometry to control the detection wavelength of individual pixels, a large number of wavelengths can be detected based on a single broadband detector material. Published by Elsevier B.V. C1 USA, Res Lab, Adelphi, MD 20783 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Polytech Univ, Brooklyn, NY 11201 USA. Princeton Univ, Princeton, NJ 08544 USA. RP Choi, KK (reprint author), USA, Res Lab, 2800 Powder Mill Rd, Adelphi, MD 20783 USA. EM kchoi@arl.army.mil RI Choi, Kwong-Kit/K-9205-2013 NR 22 TC 10 Z9 10 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1350-4495 J9 INFRARED PHYS TECHN JI Infrared Phys. Technol. PD OCT PY 2005 VL 47 IS 1-2 BP 76 EP 90 DI 10.1016/j.infrared.2005.02.013 PG 15 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 968VJ UT WOS:000232190700012 ER PT J AU Sephton, MA Botta, O AF Sephton, Mark A. Botta, Oliver TI Recognizing life in the Solar System: guidance from meteoritic organic matter SO INTERNATIONAL JOURNAL OF ASTROBIOLOGY LA English DT Article DE meteorites; molecules; organic matter; origin of life; space missions AB In the next decade, numerous space missions will attempt to detect organic matter on planets and other objects in the Solar System. Recognizing carbon-based life or its remains will be a fundamental goal of future missions. In preparation, studies of organic matter in meteorites are enabling scientists how to discriminate between biogenic and abiogenic materials. C1 [Sephton, Mark A.] Univ London Imperial Coll Sci Technol & Med, Dept Earth Sci & Engn, Impacts & Astromat Res Ctr, London SW7 2AZ, England. [Botta, Oliver] NASA, Goddard Space Flight Ctr, GEST, Greenbelt, MD 20771 USA. RP Sephton, MA (reprint author), Univ London Imperial Coll Sci Technol & Med, Dept Earth Sci & Engn, Impacts & Astromat Res Ctr, S Kensington Campus, London SW7 2AZ, England. EM m.a.sephton@imperial.ac.uk OI Sephton, Mark/0000-0002-2190-5402 FU Goddard Center for Astrobiology (a Team of the NASA Astrobiology Institute); International Space Science Institute, Bern, Switzerland FX O. B. would like to acknowledge support from the Goddard Center for Astrobiology (a Team of the NASA Astrobiology Institute) and the International Space Science Institute, Bern, Switzerland. This paper is IARC contribution 2005-0616. NR 58 TC 31 Z9 32 U1 2 U2 11 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 32 AVENUE OF THE AMERICAS, NEW YORK, NY 10013-2473 USA SN 1473-5504 J9 INT J ASTROBIOL JI Int. J. Astrobiol. PD OCT PY 2005 VL 4 IS 3-4 BP 269 EP 276 DI 10.1017/S1473550405002806 PG 8 WC Astronomy & Astrophysics; Biology; Geosciences, Multidisciplinary SC Astronomy & Astrophysics; Life Sciences & Biomedicine - Other Topics; Geology GA V28BK UT WOS:000208656100011 ER PT J AU Diaz-Calderon, A Kelly, A AF Diaz-Calderon, A Kelly, A TI On-line stability margin and attitude estimation for dynamic articulating mobile robots SO INTERNATIONAL JOURNAL OF ROBOTICS RESEARCH LA English DT Article DE stability margin; rollover prevention; mobile robot; optimal estimation; field robot; attitude estimation ID ROUGH TERRAIN; LOCOMOTION; VEHICLES; FORCE AB Stability is an important concern for vehicles which move heavy loads, accelerate or brake aggressively, turn at speed, or operate on sloped terrain. In many cases, vehicles face more than one of these challenges simultaneously. Some are obliged to execute these maneuvers when their high centers of gravity leave them particularly vulnerable to tipover or rollover A methodology is presented to estimate proximity to tipover for autonomous field robots that must be productive, effective, and self-reliant tinder such challenging circumstances. While the physical principles governing the computation of stability margin have been known for some time, the realization of these principles in practice raises issues which are at once similar to those of attitude estimation while contrasting heavily with inertial guidance. The problem of stability, margin estimation is posed in the fairly general case of accelerated articulating motion over tough terrain. Compatibility with and distinctions from attitude estimation lead to a proposed integrated solution to both problems based oil the fusion of inertial, articulation, and terrain relative velocity, sensing in an optimal estimation framework. An implementation of a device targeted to an industrial lift track is presented. C1 CALTECH, Jet Propuls Lab, Pasadena, CA 91125 USA. Carnegie Mellon Univ, Inst Robot, Pittsburgh, PA 15213 USA. RP CALTECH, Jet Propuls Lab, Pasadena, CA 91125 USA. EM adiaz@jpl.nasa.gov NR 45 TC 12 Z9 13 U1 1 U2 8 PU SAGE PUBLICATIONS LTD PI LONDON PA 1 OLIVERS YARD, 55 CITY ROAD, LONDON EC1Y 1SP, ENGLAND SN 0278-3649 EI 1741-3176 J9 INT J ROBOT RES JI Int. J. Robot. Res. PD OCT PY 2005 VL 24 IS 10 BP 845 EP 866 DI 10.1177/0278364905057865 PG 22 WC Robotics SC Robotics GA 973XD UT WOS:000232555000004 ER PT J AU Meneghini, R Liao, L Tian, L AF Meneghini, R Liao, L Tian, L TI A feasibility study for simultaneous estimates of water vapor and precipitation parameters using a three-frequency radar SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article ID SURFACE REFERENCE TECHNIQUE; WEATHER RADAR; RAMAN LIDAR; CLOUD LIQUID; TEMPERATURE; SIMULATION; PROFILES AB The radar return powers from a three-frequency radar, with center frequency at 22.235 GHz and upper and lower frequencies chosen with equal water vapor absorption coefficients, can be used to estimate water vapor density and parameters of the precipitation. A linear combination of differential measurements between the center and lower frequencies on one hand and the upper and lower frequencies on the other provide an estimate of differential water vapor absorption. The coupling between the precipitation and water vapor estimates is generally weak but increases with bandwidth and the amount of non-Rayleigh scattering of the hydrometeors. The coupling leads to biases in the estimates of water vapor absorption that depend primarily on the phase state and the median mass diameter of the hydrometeors. For a down-looking radar, path-averaged estimates of water vapor absorption are possible under rain-free as well as raining conditions by using the surface returns at the three frequencies. Simulations of the water vapor attenuation retrieval show that the largest source of error typically arises from the variance in the measured radar return powers. Although the error can be mitigated by a combination of a high pulse repetition frequency, pulse compression, and averaging in range and time, the radar receiver must be stable over the averaging period. For fractional bandwidths of 20% or less, the potential exists for simultaneous measurements at the three frequencies with a single antenna and transceiver, thereby significantly reducing the cost and mass of the system. C1 NASA, Goddard Space Flight Ctr, Instrument Sci Branch, Greenbelt, MD 20771 USA. Goddard Earth Sci & Technol Ctr, Greenbelt, MD USA. Caelum Res Corp, Greenbelt, MD USA. Goddard Earth Sci & Technol Ctr, Baltimore, MD USA. Univ Maryland Baltimore Cty, Baltimore, MD 21228 USA. RP Meneghini, R (reprint author), NASA, Goddard Space Flight Ctr, Instrument Sci Branch, Code 614-6, Greenbelt, MD 20771 USA. EM bob@neptune.gsfc.nasa.gov NR 31 TC 6 Z9 6 U1 1 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8763 J9 J APPL METEOROL JI J. Appl. Meteorol. PD OCT PY 2005 VL 44 IS 10 BP 1511 EP 1525 DI 10.1175/JAM2302.1 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 980QY UT WOS:000233034500002 ER PT J AU Wang, XH Wang, B Bos, PJ McManamon, PF Pouch, JJ Miranda, FA Anderson, JE AF Wang, XH Wang, B Bos, PJ McManamon, PF Pouch, JJ Miranda, FA Anderson, JE TI Modeling and design of an optimized liquid-crystal optical phased array SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID GRATINGS AB In this paper, the physics that determines the performance limits of a diffractive optical element based on a liquid-crystal (LC) optical phased array (OPA) is investigated by numerical modeling. The influence of the fringing electric fields, the LC material properties, and the voltage optimization process is discussed. General design issues related to the LC OPA configuration, the diffraction angle, and the diffraction efficiency are discussed. A design for a wide-angle LC OPA is proposed for high-efficiency laser beam steering. This work provides fundamental understanding for a light beam deflected by a diffractive liquid-crystal device. C1 Kent State Univ, Inst Liquid Crystal, Kent, OH 44242 USA. USAF, Res Lab, Dayton, OH 45424 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. Hana Microdisplay Technol Inc, Twinsburg, OH 44087 USA. RP Bos, PJ (reprint author), Kent State Univ, Inst Liquid Crystal, Kent, OH 44242 USA. EM pbos@lci.kent.edu NR 20 TC 29 Z9 32 U1 0 U2 8 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD OCT 1 PY 2005 VL 98 IS 7 AR 073101 DI 10.1063/1.2071450 PG 8 WC Physics, Applied SC Physics GA 973YJ UT WOS:000232558200001 ER PT J AU Liao, L Meneghini, R Iguchi, T Detwiler, A AF Liao, L Meneghini, R Iguchi, T Detwiler, A TI Use of dual-wavelength radar for snow parameter estimates SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID SIZE SPECTRA; REFLECTIVITY; RAIN; HYDROMETEORS; FREQUENCY; CONSTANTS AB Use of dual-wavelength radar, with properly chosen wavelengths, will significantly lessen the ambiguities in the retrieval of microphysical properties of hydrometeors. In this paper, a dual-wavelength algorithm is described to estimate the characteristic parameters of the snow size distributions. An analysis of the computational results, made at X and Ka bands (T-39 airborne radar) and at S and X bands (CP-2 ground-based radar), indicates that valid estimates of the median volume diameter of snow particles, Do, should be possible if one of the two wavelengths of the radar operates in the non-Rayleigh scattering region. However, the accuracy may be affected to some extent if the shape factors of the gamma distribution used for describing the particle distribution are chosen far from the true values or if cloud water attenuation is significant. To examine the validity and accuracy of the dual-wavelength radar algorithms, the algorithms are applied to the data taken from the Convective and Precipitation-Electrification Experiment (CaPE) in 1991, in which the dual-wavelength airborne radar was coordinated with in situ aircraft particle observations and ground-based radar measurements. Having carefully coregistered the data obtained from the different platforms, the airborne radar-derived size distributions are then compared with the in situ measurements and ground-based radar. Good agreement is found for these comparisons despite the uncertainties resulting from mismatches of the sample volumes among the different sensors as well as spatial and temporal offsets. C1 NASA, Goddard Space Flight Ctr, Goddard Earth Sci Technol, Caelum Res Corp, Greenbelt, MD 20771 USA. Commun Res Labs, Tokyo, Japan. S Dakota Sch Mines & Technol, Rapid City, SD USA. RP NASA, Goddard Space Flight Ctr, Goddard Earth Sci Technol, Caelum Res Corp, Code 614-6, Greenbelt, MD 20771 USA. EM lliao@priam.gsfc.nasa.gov RI PMM, JAXA/K-8537-2016 NR 32 TC 21 Z9 21 U1 1 U2 7 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 OCT PY 2005 VL 22 IS 10 BP 1494 EP 1506 DI 10.1175/JTECH1808.1 PG 13 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA 978YH UT WOS:000232908500005 ER PT J AU Mendillo, M Huang, CL Pi, XQ Rishbeth, H Meier, R AF Mendillo, M Huang, CL Pi, XQ Rishbeth, H Meier, R TI The global ionospheric asymmetry in total electron content SO JOURNAL OF ATMOSPHERIC AND SOLAR-TERRESTRIAL PHYSICS LA English DT Article DE ionosphere; ionospheric total electron content; ionospheric anomalies; thermospheric composition ID WORLDWIDE GPS NETWORK; EQUATORIAL F-REGION; SEMIANNUAL VARIATIONS; SEASONAL BEHAVIOR; F2-LAYER; IRREGULARITIES; ATMOSPHERE AB We use the NASA-JPL global ionospheric maps of total electron content (TEC), obtained from observations of GPS satellite signals, to construct average noon TEC maps for one-month periods centered on the June and December solstices of 2002. By combining data from equivalent points in the northern and southern hemispheres, we find that the combined north + south TEC in December substantially exceeds that in June, almost everywhere. The global average of an 'Asymmetry Index' (AI) used to characterize such patterns, AI = (Dec-June)/(Dec+June), results in AI = 0.15 for 2002, far greater than the value of 0.035 that corresponds to the annual variation of the solar irradiance due to Sun-Earth distance. Since the F2-layer makes the major contribution to TEC, we regard this as a manifestation of the F2-layer annual asymmetry, discovered some decades ago but never explained. The neutral atomic oxygen/molecular nitrogen concentration ratio, derived from the GUVI experiment on the TIMED satellite, shows a similar but smaller asymmetry (AI = 0.06), providing some evidence that the ionospheric asymmetry is related to changes in thermospheric composition, with a still smaller AI = 0.03 in the NRL MSIS thermospheric model. (c) 2005 Elsevier Ltd. All rights reserved. C1 Univ Southampton, Sch Phys & Astron, Southampton SO17 1BJ, Hants, England. Boston Univ, Ctr Space Phys, Boston, MA 02215 USA. CALTECH, Jet Prop Lab, NASA, Pasadena, CA 91109 USA. George Mason Univ, Sch Computat Sci, Fairfax, VA 22030 USA. RP Univ Southampton, Sch Phys & Astron, Southampton SO17 1BJ, Hants, England. EM hr@phys.soton.ac.uk RI Mendillo, Michael /H-4397-2014 NR 27 TC 62 Z9 68 U1 3 U2 9 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1364-6826 EI 1879-1824 J9 J ATMOS SOL-TERR PHY JI J. Atmos. Sol.-Terr. Phys. PD OCT PY 2005 VL 67 IS 15 BP 1377 EP 1387 DI 10.1016/j.jastp.2005.06.021 PG 11 WC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences SC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences GA 979FZ UT WOS:000232929100001 ER PT J AU Jacobson, NS Opila, EJ Myers, DL Copland, EH AF Jacobson, NS Opila, EJ Myers, DL Copland, EH TI Thermodynamics of gas phase species in the Si-O-H system SO JOURNAL OF CHEMICAL THERMODYNAMICS LA English DT Article DE silica; silicon hydroxide; silicon oxy-hydroxide; transpiration; thermodynamics; vapors ID GASEOUS SIO(OH); WATER-VAPOR; THERMOCHEMISTRY; MOLECULES; SILICA AB The transpiration method was used to study the reaction of SiO2 (cristobalite) with water vapor. Measurements were made between T = (1073 and 1728) K with water vapor contents from (0.05 to 0.6) by volume fraction in argon. From the results, the thermodynamic parameters for Si(OH)(4)(g) and SiO(OH)(2)(g) were determined. At T = (1073 to 1373) K, Si(OH)(4) is the primary vapor species and second law measurements lead to Delta(f)H degrees(1200 K) = (-1344.6 +/- 2.7) kJ(.)mol(-1) and S degrees(1200 K) = (544.4 +/- 2.1) J mol(-1) K-1. Third law measurements lead to Delta(f)H degrees(298 K) = (-1351.3 +/- 1.7) kJ(.)mol(-1). These are in very good agreement with previous measurements and previous ab initio calculations. At T = (1673 and 1728) K, there is evidence of a second vapor species, SiO(OH)2(g). By subtracting the extrapolated Si(OH)4(g) pressure, it was possible to do a third law analysis and obtain a Delta(r)H degrees(298 K) for SiO(OH)(2)(g) of (-836 +/- 40) kJ(.)mol(-1). Previous measurements and ab initio calculations are within this range. (c) 2005 Elsevier Ltd. All rights reserved. C1 NASA, Glenn Res Ctr, Div Mat, Cleveland, OH 44135 USA. E Cent Univ, Ada, OK 74820 USA. Case Western Reserve Univ, NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Jacobson, NS (reprint author), NASA, Glenn Res Ctr, Div Mat, Mail Stop 106-1,21000 Brookpk Rd, Cleveland, OH 44135 USA. EM nathan.s.jacobson@nasa.gov RI Jacobson, Nathan/A-9411-2009 NR 18 TC 48 Z9 48 U1 2 U2 21 PU ACADEMIC PRESS LTD ELSEVIER SCIENCE LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0021-9614 J9 J CHEM THERMODYN JI J. Chem. Thermodyn. PD OCT PY 2005 VL 37 IS 10 BP 1130 EP 1137 DI 10.1016/j.jct.2005.02.001 PG 8 WC Thermodynamics; Chemistry, Physical SC Thermodynamics; Chemistry GA 968UQ UT WOS:000232188400011 ER PT J AU Chorpening, B Richards, GA Casleton, KH Woike, M Willis, B Hoffman, L AF Chorpening, B Richards, GA Casleton, KH Woike, M Willis, B Hoffman, L TI Demonstration of a reheat combustor for power production with CO2 sequestration SO JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER-TRANSACTIONS OF THE ASME LA English DT Article; Proceedings Paper CT 48th International Gas Turbine and Aeroengine Congress and Exhibition CY JUN 16-19, 2003 CL ATLANTA, GA SP ASME ID SEPARATION AB Concerns about climate change have encouraged significant interest in concepts for ultralow or "zero "-emissions power generation systems. In a concept proposed by Clean Energy Systems, Inc., nitrogen is removed from the combustion air and replaced with steam diluent. In this way, formation of nitrogen oxides is prevented, and the exhaust stream can be separated into concentrated CO2 and water streams. The concentrated CO2 stream could then serve as input to a CO2 sequestration process. In this study, experimental data are reported from a full-scale combustion test using steam as the diluent in oxy-fuel combustion. This combustor represents the "reheat" combustion System in a steam cycle that uses a high and low-pressure steam expansion. The reheat combustor serves to raise the temperature of the low-pressure steam turbine inlet, similar to the reheat stage of a conventional steam power cycle. Unlike a conventional steam cycle, the reheat enthalpy is actually generated by oxy-fuel combustion in the steam flow. This paper reports on the unique design aspects of this combustor as well as initial emissions and operating performance. C1 US DOE, Natl Energy Technol Lab, Morgantown, WV 26507 USA. NASA, Glenn Res Ctr, Plum Brook Stn, Sandusky, OH 44870 USA. Clean Energy Syst Inc, Rancho Cordova, CA 95742 USA. RP Chorpening, B (reprint author), US DOE, Natl Energy Technol Lab, POB 880, Morgantown, WV 26507 USA. NR 18 TC 7 Z9 7 U1 0 U2 0 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0742-4795 J9 J ENG GAS TURB POWER JI J. Eng. Gas. Turbines Power-Trans. ASME PD OCT PY 2005 VL 127 IS 4 BP 740 EP 747 DI 10.1115/1.1924633 PG 8 WC Engineering, Mechanical SC Engineering GA 974HZ UT WOS:000232583500004 ER PT J AU Forth, SC Annigeri, BS Keat, WD AF Forth, SC Annigeri, BS Keat, WD TI Life prediction for complex structures SO JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER-TRANSACTIONS OF THE ASME LA English DT Article; Proceedings Paper CT 45th International Gas Turbine and Aeroengine Congress and Exhibition CY MAY 08-11, 2000 CL MUNICH, GERMANY ID SURFACE INTEGRAL METHOD; CRACK-GROWTH AB The surface integral method, an indirect boundary element method that represents a crack as a distribution of force dipoles, has been developed to model three-dimensional non-planar crack growth in complex structures. The finite body was effectively modeled by superposition of stress influence functions for a half-space. As a result of this strategy, only the fracture has to be discretized. Crack propagation was modeled using the maximum circumferential stress theory to predict crack direction and the Forman fatigue equation, modified with an equivalent stress intensity solution for mixed-mode, to predict extension. Comparisons with benchmark solutions and field data verified the computational methodology and defined the limits of its applicability. C1 NASA, Langley Res Ctr, United Technol Res Ctr, Hampton, VA 23682 USA. United Technol Res Ctr, E Hartford, CT 06108 USA. Union Coll, Dept Mech Engn, Schenectady, NY 12308 USA. RP Forth, SC (reprint author), NASA, Langley Res Ctr, United Technol Res Ctr, MS 188E,2 W Reid St, Hampton, VA 23682 USA. NR 20 TC 0 Z9 0 U1 0 U2 2 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0742-4795 J9 J ENG GAS TURB POWER JI J. Eng. Gas. Turbines Power-Trans. ASME PD OCT PY 2005 VL 127 IS 4 BP 814 EP 819 DI 10.1115/1.1448330 PG 6 WC Engineering, Mechanical SC Engineering GA 974HZ UT WOS:000232583500013 ER PT J AU Balint, TS Lucey, AD AF Balint, TS Lucey, AD TI Instability of a cantilevered flexible plate in viscous channel flow SO JOURNAL OF FLUIDS AND STRUCTURES LA English DT Article; Proceedings Paper CT 12th International Conference on Composites in Engineering (ICCE-12) CY AUG 01-06, 2005 CL Tenerife, SPAIN DE cantilevered flexible plate; flutter; divergence instability; upper-airway disorder; channel flow ID BOUNDARY-LAYER; UPPER AIRWAY; STABILITY; SURFACES; WALLS AB The stability of a flexible cantilevered plate in viscous channel flow is studied as a representation of the dynamics of the human upper air-way. The focus is on instability mechanisms of the soft palate (flexible plate) that cause airway blockage during sleep. We solve the Navier-Stokes equations for flow with Reynolds numbers up to 1500 fully coupled with the dynamics of the plate motion solved using finite-differences. The study is 2-D and based upon linearized plate mechanics. When both upper and lower airways are open, the plate is found to lose its stability through a flutter mechanism and a critical Reynolds number exists. When one airway is closed, the plate principally loses its stability through a divergence mechanism and a critical flow speed exists. However, below the divergence-onset flow speed, flutter can exist for low levels of structural damping in the flexible plate. Our results serve to extend understanding of flow-induced instability of cantilevered flexible plates and will ultimately improve the diagnosis and treatment of upper-airway disorders. (c) 2005 Elsevier Ltd. All rights reserved. C1 Curtin Univ Technol, Dept Mech Engn, Perth, WA 6845, Australia. CALTECH, Jet Propuls Lab, Pasadena, CA 91125 USA. RP Lucey, AD (reprint author), Curtin Univ Technol, Dept Mech Engn, POB U1987, Perth, WA 6845, Australia. EM a.lucey@curtin.edu.au NR 19 TC 67 Z9 67 U1 2 U2 11 PU ACADEMIC PRESS LTD ELSEVIER SCIENCE LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0889-9746 J9 J FLUID STRUCT JI J. Fluids Struct. PD OCT PY 2005 VL 20 IS 7 SI SI BP 893 EP 912 DI 10.1016/j.jfluidstructs.2005.05.005 PG 20 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA 960YI UT WOS:000231628700002 ER PT J AU Gottschalck, J Meng, J Rodell, M Houser, P AF Gottschalck, J Meng, J Rodell, M Houser, P TI Analysis of multiple precipitation products and preliminary assessment of their impact on global land data assimilation system land surface states SO JOURNAL OF HYDROMETEOROLOGY LA English DT Article ID SATELLITE RAIN ESTIMATION; REAL-TIME ESTIMATION; CLIMATOLOGY PROJECT; GAUGE OBSERVATIONS; SOIL-MOISTURE; UNITED-STATES; INTERCOMPARISON PROJECT; ALGORITHM; DROUGHT; MODEL AB Precipitation is arguably the most important meteorological forcing variable in land surface modeling. Many types of precipitation datasets exist ( with various pros and cons) and include those from atmospheric data assimilation systems, satellites, rain gauges, ground radar, and merged products. These datasets are being evaluated in order to choose the most suitable precipitation forcing for real-time and retrospective simulations of the Global Land Data Assimilation System (GLDAS). This paper first presents results of a comparison for the period from March 2002 to February 2003. Later, GLDAS simulations 14 months in duration are analyzed to diagnose impacts on GLDAS land surface states when using the Mosaic land surface model (LSM). A comparison of seasonal total precipitation for the continental United States (CONUS) illustrates that the Climate Prediction Center (CPC) Merged Analysis of Precipitation (CMAP) has the closest agreement with a CPC rain gauge dataset for all seasons except winter. The European Centre for Medium-Range Weather Forecasts (ECMWF) model performs the best of the modeling systems. The satellite-only products [the Tropical Rainfall Measuring Mission (TRMM) Real-time Multi-satellite Precipitation Analysis and the Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks (PERSIANN)] suffer from a few deficiencies - most notably an overestimation of summertime precipitation in the central United States ( 200 - 400 mm). CMAP is the most closely correlated with daily rain gauge data for the spring, fall, and winter seasons, while the satellite-only estimates perform best in summer. GLDAS land surface states are sensitive to different precipitation forcing where percent differences in volumetric soil water content (SWC) between simulations ranged from -75% to -100%. The percent differences in SWC are generally 25%-75% less than the percent precipitation differences, indicating that GLDAS and specifically the Mosaic LSM act to generally "damp" precipitation differences. Areas where the percent changes are equivalent to the percent precipitation changes, however, are evident. Soil temperature spread between GLDAS runs was considerable and ranged up to +/- 3.0 K with the largest impact in the western United States. C1 Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, GEST, Baltimore, MD 21228 USA. NASA, Goddard Space Flight Ctr, Hydrol Sci Branch, Greenbelt, MD 20771 USA. RP Gottschalck, J (reprint author), NOAA, Natl Ctr Environm Predict, Climate Predict Ctr, 5220 Auth Rd, Camp Springs, MD 20746 USA. EM Jon.Gottschalck@noaa.gov RI Rodell, Matthew/E-4946-2012; Houser, Paul/J-9515-2013 OI Rodell, Matthew/0000-0003-0106-7437; Houser, Paul/0000-0002-2991-0441 NR 58 TC 103 Z9 108 U1 1 U2 17 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 1525-755X J9 J HYDROMETEOROL JI J. Hydrometeorol. PD OCT PY 2005 VL 6 IS 5 BP 573 EP 598 DI 10.1175/JHM437.1 PG 26 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 984FV UT WOS:000233288800001 ER PT J AU Mahanama, SPP Koster, RD AF Mahanama, SPP Koster, RD TI AGCM biases in evaporation regime: Impacts on soil moisture memory and land-atmosphere feedback SO JOURNAL OF HYDROMETEOROLOGY LA English DT Article ID SURFACE PARAMETERIZATION SCHEMES; RIVER-BASIN EXPERIMENT; CLIMATE; PRECIPITATION; PROJECT; SYSTEM; MODELS; INITIALIZATION; PREDICTABILITY; TEMPERATURE AB Because precipitation and net radiation in an atmospheric general circulation model (AGCM) are typically biased relative to observations, the simulated evaporative regime of a region may be biased, with consequent negative effects on the AGCM's ability to translate an initialized soil moisture anomaly into an improved seasonal prediction. These potential problems are investigated through extensive offline analyses with the Mosaic land surface model (LSM). The LSM was first forced globally with a 15-yr observation-based dataset. The simulation was then repeated after imposing a representative set of GCM climate biases onto theforcings- the observational forcings were scaled so that their mean seasonal cycles matched those simulated by the NASA Seasonal-to-Interannual Prediction Project (NSIPP-1; NASA Global Modeling and Assimilation Office) AGCM over the same period. The AGCM's climate biases do indeed lead to significant biases in evaporative regime in certain regions, with the expected impacts on soil moisture memory time scales. Furthermore, the offline simulations suggest that the biased forcing in the AGCM should contribute to overestimated feedback in certain parts of North America-parts already identified in previous studies as having excessive feedback. The present study thus supports the notion that the reduction of climate biases in the AGCM will lead to more appropriate translations of soil moisture initialization into seasonal prediction skill. C1 NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Greenbelt, MD 20771 USA. Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. RP NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Code 610-1, Greenbelt, MD 20771 USA. EM sarith@gmao.gsfc.nasa.gov RI Koster, Randal/F-5881-2012 OI Koster, Randal/0000-0001-6418-6383 NR 35 TC 12 Z9 12 U1 0 U2 2 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 OCT PY 2005 VL 6 IS 5 BP 656 EP 669 DI 10.1175/JHM446.1 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 984FV UT WOS:000233288800005 ER PT J AU Sharpe, WN Jadaan, O Beheim, GM Quinn, GD Nemeth, NN AF Sharpe, WN Jadaan, O Beheim, GM Quinn, GD Nemeth, NN TI Fracture strength of silicon carbide microspecimens SO JOURNAL OF MICROELECTROMECHANICAL SYSTEMS LA English DT Article DE fracture strength; microspecimens; microstructure; silicon carbide; size effect; tensile tests; Weibull statistics ID CERAMIC COMPONENTS; POLYSILICON; DURABILITY; DEPOSITION AB Polycrystalline silicon carbide tensile microspecimens 3.1 mm long were produced by deep reactive ion etching of wafers on the order of 150 mu m thick. The gage sections, which were nominally 200 mu m wide, were either straight, slightly curved, or contained double notches in order to vary the size of the highly stressed region. The fracture stresses of 190 specimens from three process runs were measured in a novel test setup. The average local fracture strengths for the last run were: straight 0.38 +/- 0.13 GPa, curved 0.47 +/- 0.15 GPa, notched 0.78 +/- 0.28 GPa. The corresponding Weibull characteristic strengths were, 0.42 GPa, 0.53 GPa, and 0.88 GPa with respective moduli 3.3, 3.4, and 3.1. These results show a clear increase in the strength of the material as the size of the highly stressed region decreases. Fractographic analyzes showed failures initiating from the bottoms of side grooves left by the etching process. The grains of the material were quite heterogeneous, varying from a few microns in size to columnar grains through the entire specimen thickness. The curved specimens were used as the base for predicting the probability of failure of the other two shapes. While the Weibull approach was quite accurate for the straight shape, it over-predicted the strengths of the notched specimens. Given the microstructure of the material relative to the size of the specimen, a continuum analysis is questionable. C1 Johns Hopkins Univ, Baltimore, MD 21218 USA. Univ Wisconsin, Platteville, WI 53818 USA. NASA, Glenn Ctr, Cleveland, OH 44135 USA. NIST, Gaithersburg, MD 20899 USA. RP Sharpe, WN (reprint author), Johns Hopkins Univ, Baltimore, MD 21218 USA. NR 25 TC 39 Z9 39 U1 2 U2 8 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 1057-7157 J9 J MICROELECTROMECH S JI J. Microelectromech. Syst. PD OCT PY 2005 VL 14 IS 5 BP 903 EP 913 DI 10.1109/JMEMS.2005.851862 PG 11 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Instruments & Instrumentation; Physics, Applied SC Engineering; Science & Technology - Other Topics; Instruments & Instrumentation; Physics GA 974DH UT WOS:000232571000004 ER PT J AU Jamison, TL Kornreich, P Yu, C AF Jamison, TL Kornreich, P Yu, C TI Novel intercore-cladding lithium niobate thin film coated MOEMS fiber sensor/modulator SO JOURNAL OF MICROLITHOGRAPHY MICROFABRICATION AND MICROSYSTEMS LA English DT Article; Proceedings Paper CT Conference on Micromachining Technology for Micro-Optics and Nano-Optics II CY JAN 27-29, 2004 CL San Jose, CA SP SPIE DE lithium niobate; fiber modulator/sensor; sol gel fiber; electro-optic; modulator; acousto-optic sensor AB A MOEMS fiber modulator/sensor is fabricated by depositing a lithium niobate sol-gel thin film between the core and cladding of a fiber preform. The preform is then drawn into 125-mu m fibers. Such a MOEMS modulator design is expected to enhance existing lithium niobate undersea acousto-optic sound wave detectors. In our proposed version, the lithium niobate thin film alters the ordinary silica core/cladding boundary conditions such that, when a stress or strain is applied to the fiber, the core light confinement factor changes, leading to modulation of fiber light transmission. Test results of the lithium niobate embedded fiber with a 1550-nm, 4-mW laser source revealed a reduction in light transmission with applied tension. As a comparison, using the same laser source, an ordinary silica core/cladding fiber did not exhibit any reduction in transmitted light when the same strain was applied. Further experimental work and theoretical analysis is ongoing. (c) 2005 Society of Photo-Optical Instrumentation Engineers. C1 NASA, Goddard Space Flight Ctr, Parts Packaging & Assembly Off, Greenbelt, MD 20771 USA. Syracuse Univ, Dept Elect & Comp Engn, Syracuse, NY 13244 USA. N Carolina Agr & Tech State Univ, Dept Elect & Comp Engn, Greensboro, NC 27411 USA. RP NASA, Goddard Space Flight Ctr, Parts Packaging & Assembly Off, Code 661, Greenbelt, MD 20771 USA. EM Tracee.L.Jamison@nasa.gov NR 12 TC 0 Z9 0 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 1537-1646 J9 J MICROLITH MICROFAB JI J. Microlithogr. Microfabr. Microsyst. PD OCT-DEC PY 2005 VL 4 IS 4 AR 041302 DI 10.1117/1.2114667 PG 5 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Optics SC Engineering; Science & Technology - Other Topics; Materials Science; Optics GA 005XK UT WOS:000234859500004 ER PT J AU Wesolek, DM Hererro, FA Osiander, R Darrin, MAG AF Wesolek, DM Hererro, FA Osiander, R Darrin, MAG TI Design, fabrication, and performance of a micromachined plasma spectrometer SO JOURNAL OF MICROLITHOGRAPHY MICROFABRICATION AND MICROSYSTEMS LA English DT Article; Proceedings Paper CT Conference on MEMS/MOEMS Components and Their Applications CY JAN 26-27, 2004 CL San Jose, CA SP SPIE DE imaging spectrometer; microelectromechanical systems; deep-reactive ion etch; electric discharge machining; flat plasma spectrometer AB Through the application of a new approach to energy analysis to microelectromechanical systems, the flat plasma spectrometer (FlaPS) provides a solution to the investigation of plasma distributions in space. It is capable of measuring the kinetic energy and angular distributions of ions in the space environment for energies ranging from a few eV to 50 keV. A single pixel of a FlaPS instrument has been designed, built, and tested to occupy a volume of 1 cm(3), and is characterized by a high throughput-to-volume ratio, making it an ideal component for small-scale satellites. The focus of this work is on the design, fabrication, simulation, and testing of the instrument front end that consists of a collimator, parallel plate energy analyzer, and energy selector mask. Advanced microfabrication techniques enable fabrication of the miniature plasma spectrometer with geometric factor 4.9x10(-5) cm(2)-sr per pixel and an entrance aperture area of 0.01 cm(2). Arrays of narrow collimator channels with 4-deg angular divergence and high transmission allow energy analysis of ions without the need for focusing, the key feature that enables large mass reduction. It is also shown that the large plate factors achievable with this approach to energy analysis offer definite advantages in reducing the need for excessively high voltages. (c) 2005 Society of Photo-Optical Instrumentation Engineers. C1 Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. NASA Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. EM danielle.wesolek@jhuapl.edu RI Darrin, Margaret/H-4305-2011; Osiander, Robert/J-5781-2015 OI Osiander, Robert/0000-0001-9672-5513 NR 7 TC 5 Z9 5 U1 2 U2 6 PU SPIE-SOC PHOTO-OPTICAL INSTRUMENTATION ENGINEERS PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98225 USA SN 1537-1646 J9 J MICROLITH MICROFAB JI J. Microlithogr. Microfabr. Microsyst. PD OCT-DEC PY 2005 VL 4 IS 4 AR 041403 DI 10.1117/1.2114767 PG 7 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Optics SC Engineering; Science & Technology - Other Topics; Materials Science; Optics GA 005XK UT WOS:000234859500009 ER PT J AU Pickett, HM Pearson, JC Miller, CE AF Pickett, HM Pearson, JC Miller, CE TI Use of Euler series to fit spectra with application to water SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article DE water; Euler ID PADE HAMILTONIAN OPERATOR; ROTATIONAL TRANSITIONS; LINE POSITIONS; HOT BANDS; CM(-1) REGION; ENERGY-LEVELS; GROUND-STATE; H2O; MOLECULE; CM-1 AB Power series expansions of water eigenstate energies in J and K converge poorly and show alternating signs of the coefficients of the power series. Euler series can be used effectively to change an alternating series into one where all the coefficients have the same sign and where the radius of convergence is increased. This paper extends the Euler series to a two-dimensional series in K-2 and [J(J + 1) - K-2]. Application of this Euler series to the rotational energies of the ground state and the first 4 excited vibrational states of water allows a fit to experimental accuracy to J = 22 and K = 22. This fit has good convergence and also has predictive capability. It is much easier to fit the perturbed states because the Euler series allows the zero-order energy the perturbed states to be predicted with more confidence. Published by Elsevier Inc. C1 CALTECH, Jet Propuls Lab, Pasadena, CA 91109 USA. RP Pickett, HM (reprint author), CALTECH, Jet Propuls Lab, Pasadena, CA 91109 USA. EM Herbert.M.Pickett@jpl.nasa.gov NR 27 TC 17 Z9 20 U1 0 U2 5 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-2852 J9 J MOL SPECTROSC JI J. Mol. Spectrosc. PD OCT PY 2005 VL 233 IS 2 BP 174 EP 179 DI 10.1016/j.jms.2005.06.013 PG 6 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 971TK UT WOS:000232407400003 ER PT J AU Carpenter, MH Kennedy, CA Bijl, H Viken, SA Vatsa, VN AF Carpenter, MH Kennedy, CA Bijl, H Viken, SA Vatsa, VN TI Fourth-order Runge-Kutta schemes for fluid mechanics applications SO JOURNAL OF SCIENTIFIC COMPUTING LA English DT Article; Proceedings Paper CT Workshop on Advances and Challenges in Time-Integration of PDEs CY AUG 18-20, 2003 CL Brown Univ, Providence, RI SP USAF Off Sci Res HO Brown Univ DE high-order; time discretization; Runge-Kutta; backward differentiation formulae; modified extended backward differentiation formulae; efficiency; convection-diffusion-reaction; turbulence ID BACKWARD DIFFERENTIATION FORMULAS; CONTROL-THEORETIC TECHNIQUES; NAVIER-STOKES EQUATIONS; STEPSIZE SELECTION; INTEGRATION; ODES; SOLVERS AB Multiple high-order time-integration schemes are used to solve stiff test problems related to the Navier-Stokes (NS) equations. The primary objective is to determine whether high-order schemes can displace currently used second-order schemes on stiff NS and Reynolds averaged NS (RANS) problems, for a meaningful portion of the work-precision spectrum. Implicit-Explicit (IMEX) schemes are used on separable problems that naturally partition into stiff and nonstiff components. Non-separable problems are solved with fully implicit schemes, oftentimes the implicit portion of an IMEX scheme. The convection-diffusion-reaction (CDR) equations allow a term by term stiff/nonstiff partition that is often well suited for IMEX methods. Major variables in CDR converge at near design-order rates with all formulations, including the fourth-order IMEX additive Runge-Kutta (ARK(2)) schemes that are susceptible to order reduction. The semi-implicit backward differentiation formulae and IMEX ARK(2) schemes are of comparable efficiency. Laminar and turbulent aerodynamic applications require fully implicit schemes, as they are not profitably partitioned. All schemes achieve design-order convergence rates on the laminar problem. The fourth-order explicit singly diagonally implicit Runge-Kutta (ESDIRK4) scheme is more efficient than the popular second-order backward differentiation formulae (BDF2) method. The BDF2 and fourth-order modified extended backward differentiation formulae (MEBDF4) schemes are of comparable efficiency on the turbulent problem. High precision requirements slightly favor the MEBDF4 scheme (greater than three significant digits). Significant order reduction plagues the ESDIRK4 scheme in the turbulent case. The magnitude of the order reduction varies with Reynolds number. Poor performance of the high-order methods can partially be attributed to poor solver performance. Huge time steps allowed by high-order formulations challenge the capabilities of algebraic solver technology. C1 NASA, Computat Methods & Simulat Branch, Langley Res Ctr, Hampton, VA 23681 USA. Delft Univ Technol, Dept Aerosp Engn, Delft, Netherlands. NASA, Flow Phys & Control Branch, Langley Res Ctr, Hampton, VA 23681 USA. RP Carpenter, MH (reprint author), NASA, Computat Methods & Simulat Branch, Langley Res Ctr, Hampton, VA 23681 USA. NR 33 TC 25 Z9 25 U1 0 U2 9 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0885-7474 J9 J SCI COMPUT JI J. Sci. Comput. PD OCT PY 2005 VL 25 IS 1 BP 157 EP 194 DI 10.1007/s10915-004-4637-3 PG 38 WC Mathematics, Applied SC Mathematics GA 990GD UT WOS:000233730300010 ER PT J AU Choi, SR Zhu, DM Miller, RA AF Choi, SR Zhu, DM Miller, RA TI Effect of sintering on mechanical properties of plasma-sprayed zirconia-based thermal barrier coatings SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID MIXED-MODE FRACTURE; HEAT-TREATMENT; PERCENT Y2O3; II FRACTURE; BEHAVIOR; DEFORMATION; TOUGHNESS; COMPRESSION; CERAMICS; FATIGUE AB The effect of sintering on the mechanical properties of freestanding, plasma-sprayed ZrO2-8 wt% Y2O3 thick thermal barrier coatings (TBCs) was determined after annealing at 1316 degrees C in air. Mechanical properties of the TBCs, including flexure strength, modes I and II fracture toughnesses, constitutive relations, elastic modulus, and microhardness, were determined at ambient temperature as a function of annealing time ranging from 0 to 500 h. In addition, some physical properties such as density and phase stability were also determined. Mechanical and physical properties increased significantly in 5-100 h and then reached a plateau above 100 h. An exception to this was the monoclinic phase that increased monotonically without forming a plateau. Annealing resulted in healing of microcracks and pores, and in grain growth, accompanying densification of the TBC's body because of the sintering effect. However, an inevitable adverse effect also occurred such that the desired lower thermal conductivity and good strain-tolerant capability, which makes the TBCs unique in thermal barrier applications, were degraded upon annealing. A phenomenological model was proposed to assess and quantify all the property variables in response to annealing in a normalized scheme. C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Choi, SR (reprint author), NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. EM sung.r.choi@grc.nasa.gov NR 41 TC 44 Z9 46 U1 2 U2 28 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 OCT PY 2005 VL 88 IS 10 BP 2859 EP 2867 DI 10.1111/j.1551-2916.2005.0050.x PG 9 WC Materials Science, Ceramics SC Materials Science GA 964HD UT WOS:000231869100029 ER PT J AU Canelon, JI Malki, HA Jacklin, SA Shieh, LS AF Canelon, JI Malki, HA Jacklin, SA Shieh, LS TI An adaptive neural network model for vibration control in a Blackhawk helicopter SO JOURNAL OF THE AMERICAN HELICOPTER SOCIETY LA English DT Article AB This work presents an adaptive neural network approach for the identification of a model for the control of the vibration in a Blackhawk helicopter. A feedforward neural network is used to identify a nonlinear model relating the higher harmonic blade pitch motion to the vibration state. An optimal linearization approach is applied at every operating point of interest to obtain a linear model that is locally equivalent to the neural network model at that particular operating point. This linear model can be used to obtain optimal vibration control commands. The data used for development of the model were obtained during the wind tunnel testing of the Blackhawk (UH-60A) rotor in the NASA 80-by-120-foot wind tunnel. Two different modeling approaches were used, linear quasi-static and state-space. The proposed neural-network method of system identification was compared to the least squares method. This comparison showed that the neural network consistently produced lower identification errors. The results obtained also reveal that the approximation performance improves when both the coefficients of the blade pitch motion control commands and the flight parameters are used as inputs. C1 Univ Houston, Dept Elect & Comp Engn, Houston, TX 77004 USA. Univ Houston, Dept Engn Technol, Houston, TX 77004 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Canelon, JI (reprint author), Univ Houston, Dept Elect & Comp Engn, Houston, TX 77004 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU AMER HELICOPTER SOC INC PI ALEXANDRIA PA 217 N WASHINGTON ST, ALEXANDRIA, VA 22314 USA SN 0002-8711 J9 J AM HELICOPTER SOC JI J. Am. Helicopter Soc. PD OCT PY 2005 VL 50 IS 4 BP 349 EP 353 PG 5 WC Engineering, Aerospace SC Engineering GA 979JR UT WOS:000232938700006 ER PT J AU Mettler, E Breckenridge, WG Quadrelli, MB AF Mettler, Edward Breckenridge, William G. Quadrelli, Marco B. TI Large aperture space telescopes in formation: Modeling, metrology, and control SO JOURNAL OF THE ASTRONAUTICAL SCIENCES LA English DT Article; Proceedings Paper CT International Symposium on Formation Flying CY OCT 29-31, 2002 CL Toulouse, FRANCE AB In this paper we summarize a concept definition and feasibility analysis for formation flying a representative large space telescope composed of separated optical elements. A virtual-structure construct (an equivalent rigid body) is created by unique metrology and control that combines both centralized and decentralized methods. The formation may be in orbit at GEO for super-resolution Earth observation or it may be in an Earth-trailing orbit for astrophysics. Extended applications are envisioned for exo-solar planet interferometric imaging by a formation of very large separated optics telescopes. Space telescopes, with such large apertures and optics with focal length f/10 to f/100, are not feasible if connected by massive metering structures. Instead, the new virtual-structure paradigm of information and control connectivity between the formation elements provides the necessary spatial rigidity and alignment precision for the telescope. C1 CALTECH, Jet Prop Lab, Guidance & Control Anal Grp, Pasadena, CA 91109 USA. RP Mettler, E (reprint author), CALTECH, Jet Prop Lab, Guidance & Control Anal Grp, Mail Stop 198-136B, Pasadena, CA 91109 USA. EM Edward.Mettler@jpl.nasa.gov; William.G.Breckenridge@jpl.nasa.gov; Marco.B.Quadrelli@jpl.nasa.gov NR 11 TC 1 Z9 1 U1 0 U2 1 PU AMER ASTRONAUTICAL SOC PI SPRINGFIELD PA 6352 ROLLING MILL PLACE SUITE 102, SPRINGFIELD, VA 22152 USA SN 0021-9142 J9 J ASTRONAUT SCI JI J. Astronaut. Sci. PD OCT-DEC PY 2005 VL 53 IS 4 BP 391 EP 412 PG 22 WC Engineering, Aerospace SC Engineering GA 072ZI UT WOS:000239711400003 ER PT J AU Chang, HR Smith, DD AF Chang, HR Smith, DD TI Gain-assisted superluminal propagation in coupled optical resonators SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID RING LASER; LIGHT; SYSTEM; DELAY AB We predict transparent superluminal pulse propagation in coresonant coupled optical resonators when a gain element is placed in the resonator closest to the excitation waveguide, provided that the structure is overcoupled, but the resonator farthest from the excitation waveguide is undercoupled sufficiently to avoid lasing at the split modes. The effective steady-state absorptive and dispersive response of coupled resonators are derived, and the coupled-mode approximation is used to determine the conditions for transparent superluminal pulse propagation in these systems. In addition, we find that the effect of pulse compression is minimized when the structure is critically coupled. (c) 2005 Optical Society of America. C1 NASA, George C Marshall Space Flight Ctr, Sci & Technol Directorate, Huntsville, AL 35812 USA. Univ Alabama, Dept Phys, Huntsville, AL 35899 USA. RP Smith, DD (reprint author), NASA, George C Marshall Space Flight Ctr, Sci & Technol Directorate, XD42, Huntsville, AL 35812 USA. EM david.d.smith@nasa.gov NR 25 TC 22 Z9 23 U1 0 U2 5 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 OCT PY 2005 VL 22 IS 10 BP 2237 EP 2241 DI 10.1364/JOSAB.22.002237 PG 5 WC Optics SC Optics GA 973UY UT WOS:000232549300023 ER PT J AU Shabbir, A Adamczyk, JJ AF Shabbir, A Adamczyk, JJ TI Flow mechanism for stall margin improvement due to circumferential casing grooves on axial compressors SO JOURNAL OF TURBOMACHINERY-TRANSACTIONS OF THE ASME LA English DT Article ID SIMULATION AB A computational study is carried out to understand the physical mechanism responsible for the improvement in stall margin of an axial flow rotor due to the circumferential casing grooves. Computational fluid dynamics simulations shou, an increase in operating range of the low speed rotor in the presence of casing grooves. A budget of the axial momentum equation is carried out at the rotor casing in the tip gap in order to understand the physical process behind this stall margin improvement. It is shown that for the smooth casing the net a-vial pressure force at the rotor casing in the tip, gap is balanced by the net axial shear stress force. However; for the grooved casing the net axial shear stress force acting at the casing is augmented by the axial force due to the radial transport of axial momentum, which occurs across the grooves and power stream. interface. This additional force adds to the net axial viscous shear force and thus leads to an increase in the stall margin of the rotor. C1 Univ Toledo, Cleveland, OH 44135 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Shabbir, A (reprint author), Univ Toledo, 21000 Brookpk Rd,MS 5-9, Cleveland, OH 44135 USA. EM aamir.shabbir@grc.nasa.gov NR 24 TC 54 Z9 58 U1 3 U2 17 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0889-504X J9 J TURBOMACH JI J. Turbomach.-Trans. ASME PD OCT PY 2005 VL 127 IS 4 BP 708 EP 717 DI 10.1115/1.2008970 PG 10 WC Engineering, Mechanical SC Engineering GA 981XL UT WOS:000233121200007 ER PT J AU McAdams, DA Tumer, IY AF McAdams, DA Tumer, IY TI Toward intelligent fault detection in turbine blades: Variational vibration models of damaged pinned-pinned beams SO JOURNAL OF VIBRATION AND ACOUSTICS-TRANSACTIONS OF THE ASME LA English DT Article ID CRACKS AB Inaccuracies in the modeling assumptions about the distributional characteristics of the monitored signatures have been shown to cause frequent false positives in vehicle monitoring systems for high-risk aerospace applications. To enable the development of robust fault detection methods, this work explores the deterministic as well as variational characteristics of failure signatures. Specifically, we explore the combined impact of crack damage and manufacturing variation on the vibrational characteristics of turbine blades modeled as pinned-pinned beams. The changes in the transverse vibration and associated eigenfrequencies of the beams are considered. Specifically., a complete variational beam vibration model is developed and presented that allows variations in geometry and material properties to be considered, with and without crack damage. To simplify variational simulation, separation of variables is used for fast simulations. This formulation is presented in detail. To establish a baseline of the effect of geometric variations on the system vibrational response, a complete numerical example is presented that includes damaged beams of ideal geometry and damaged beams with geometric variation. It is shown that changes in fault detection monitoring signals caused by geometric variation are small with those caused by damage and impending failure. Also, when combined, the impact of geometric variation and damage appear to be C1 Univ Missouri, Dept Mech & Aerosp Engn Mech, Rolla, MO 65409 USA. NASA, Ames Res Ctr, Computat Sci Div MS 2693, Moffett Field, CA 94035 USA. RP McAdams, DA (reprint author), Univ Missouri, Dept Mech & Aerosp Engn Mech, Rolla, MO 65409 USA. EM dmcadams@umr.edu; itumer@mail.arc.nasa.gov NR 31 TC 2 Z9 2 U1 1 U2 2 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 1048-9002 J9 J VIB ACOUST JI J. Vib. Acoust.-Trans. ASME PD OCT PY 2005 VL 127 IS 5 BP 467 EP 474 DI 10.1115/1.2013296 PG 8 WC Acoustics; Engineering, Mechanical; Mechanics SC Acoustics; Engineering; Mechanics GA 972EB UT WOS:000232435800006 ER PT J AU Johnson, A Salvador, G Kenney, J Robbins, J Landry, S Clapham, P AF Johnson, A Salvador, G Kenney, J Robbins, J Landry, S Clapham, P TI Fishing gear involved in entanglements of right and humpback whales SO MARINE MAMMAL SCIENCE LA English DT Article DE entanglement; entanglement risk; mortality; fisheries; bycatch; gear type; North Atlantic right whale; Eubalaena glacialis; humpback whale; Megaptera novaeangliae AB Interactions between marine mammals and fishing gear are an issue of global concern. Entanglements in the western North Atlantic are a major source of injury and mortality for endangered large whales. In this study, entanglements of 31 right whales (Eubalaena glacialis) and 30 humpback whales (Megaptera. novaeangliae) were analyzed to determine the types and parts of gear involved. When gear was identified, 89% (n = 32) of the entanglements were attributed to pot and gill net gear; however, a wide range of specific gear types were implicated. Despite gear recovery, gear type was not identified in 20% (n = 9) of the cases. Although pot gear was recovered from both species equally, gill net gear was less frequently retrieved from right whales (n 2) than humpback whales (n = 11). When gear part was identified, 81% (n = 2 1) involved entanglements in buoy line and/or groundline. For right whales, the most common point of gear attachment was the mouth (77.4%); for humpback whales, the tail (53%) and the mouth (43%) were common attachment sites. Four right and three humpback whales in this sample were known to have died subsequent to entanglement. However, when identified, the gear types and parts involved in lethal cases were not substantially different from entanglements with non-lethal outcomes. Large whales can become entangled in a wide variety of fishing gear types and parts, and additional insight will depend on continued efforts to document entanglements and recover associated gear. C1 Duke Univ, Marine Lab, Beaufort, NC 28516 USA. Natl Marine Fisheries Serv, Lewes, DE 19958 USA. Natl Marine Fisheries Serv, Fisheries Engn Grp, N Kingstown, RI 02852 USA. Provincetown Ctr Coastal Studies, Provincetown, MA 02657 USA. Edgerton Res Lab, Boston, MA 02110 USA. Natl Marine Mammal Lab, Alaska Fisheries Sci Ctr, Seattle, WA 98115 USA. RP Johnson, A (reprint author), Duke Univ, Marine Lab, 135 Duke Marine Lab Rd, Beaufort, NC 28516 USA. EM amanda.johnson@noaa.gov NR 11 TC 49 Z9 56 U1 4 U2 29 PU SOC MARINE MAMMALOGY PI LAWRENCE PA 1041 NEW HAMPSHIRE ST, LAWRENCE, KS 66044 USA SN 0824-0469 J9 MAR MAMMAL SCI JI Mar. Mamm. Sci. PD OCT PY 2005 VL 21 IS 4 BP 635 EP 645 DI 10.1111/j.1748-7692.2005.tb01256.x PG 11 WC Marine & Freshwater Biology; Zoology SC Marine & Freshwater Biology; Zoology GA 970IB UT WOS:000232297400004 ER PT J AU Speich, JE Cagle, YD Rafiq, A Merrell, RC Doarn, CR Broderick, TJ AF Speich, JE Cagle, YD Rafiq, A Merrell, RC Doarn, CR Broderick, TJ TI Evaluation of surgical skills in microgravity using force sensing SO MEDICAL ENGINEERING & PHYSICS LA English DT Article DE surgery; laparoscopic; suturing; clip-applying; training; parabolic flight; aerospace ID SURGERY AB Introduction: Force measurements can be used to characterize surgical maneuvers in microgravity. Methods: A series of surgical tasks was performed by a group of 20 participants (n=20) both in 1 g on the ground and in 0 g aboard NASA's KC-135 aircraft in parabolic flight. The group included astronauts, a flight surgeon, surgeons, physicians, Ph.D. -scientists, and technical personnel. The interaction forces between the surgical instruments and the mock tissue were measured for a clip-applying, suturing, grasping, and cutting. Seven evaluations in 1g and a single evaluation in 0 g were performed by each of the participants. Results: The data from a single participant are examined in detail. Statistical results for the group of 20 participants do not show significant differences in the average or peak forces during clip-applying or in the average forces applied during suturing in 0 g versus in 1g. However, the results do show statistically greater (43% higher) peak forces during suturing in microgravity. Discussion: These data show the usefulness of analyzing force information to assess surgical task performance in microgravity. Although peak suturing forces were statistically higher in microgravity, their clinical relevance is unknown, but likely would not result in a change in clinical outcome. Overall, the data suggest that forces exerted during surgical tasks will not pose a significant barrier to effective surgery in microgravity. (c) 2005 IPEM. Published by Elsevier Ltd. All rights reserved. C1 Virginia Commonwealth Univ, Dept Mech Engn, Richmond, VA 23284 USA. NASA, Lyndon B Johnson Space Ctr, Astronaut Off, Houston, TX 77058 USA. Virginia Commonwealth Univ, Dept Surg, Med Informat & Technol Applicat Consortium, Richmond, VA 23284 USA. Univ Cincinnati, Dept Surg, Ctr Surg Innovat, Cincinnati, OH USA. RP Speich, JE (reprint author), Virginia Commonwealth Univ, Dept Mech Engn, 601 W Main St,Room 310,POB 843015, Richmond, VA 23284 USA. EM jespeich@vcu.edu RI Speich, John/F-6246-2011 NR 9 TC 5 Z9 5 U1 1 U2 3 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1350-4533 J9 MED ENG PHYS JI Med. Eng. Phys. PD OCT PY 2005 VL 27 IS 8 BP 687 EP 693 DI 10.1016/j.medengphy.2005.02.005 PG 7 WC Engineering, Biomedical SC Engineering GA 966QO UT WOS:000232036100006 PM 16139766 ER PT J AU Cleek, TM Whalen, RT AF Cleek, TM Whalen, RT TI Effect of activity and age on long bones using a new densitometric technique SO MEDICINE AND SCIENCE IN SPORTS AND EXERCISE LA English DT Article DE structural properties; geometry; running; tibia; x-ray absorptiometry ID X-RAY ABSORPTIOMETRY; DUAL PHOTON-ABSORPTIOMETRY; PHYSICAL-ACTIVITY; STRESS-FRACTURES; FEMORAL-SHAFT; STRENGTH; PRECISION; RECRUITS; DENSITY; INERTIA AB Introduction: Long bone structural parameters such as cross-sectional area or area moments of inertia are useful measures of long bone mechanical properties. We implemented a three-scan densitometric method to measure structural parameters in long bones of the lower leg in vivo. The validated method was applied to investigate the relationship between activity level, age, and long bone structural parameters in women. Methods: An aluminum phantom was used to estimate in vivo setup accuracy. In vivo precision was determined by same-day repeated measures on human subjects. For the activity study, women were recruited in two age groups (25-35, 60+yr) and two activity levels (recreational runners, nonrunners). Scans were taken of the middle third of the lower right leg; structural parameters for the tibia and fibula were determined at each scan line, averaged over the section, and adjusted by factors accounting for body size variations. Results: Aluminum phantom cross-sectional area was underestimated by 4-6%, principal moments were underestimated by < 5%, and principal angles were within +/- 1.2 degrees. In vivo precision results (lower energy, scans spanning 60 degrees) indicated coefficients of variation for cross-sectional area (A), principal moments of inertia (Imax, Imin), and polar moment of inertia (J) of 0.52, 5.87, 2.22, and 3.82%, respectively. The activity study showed mean adjusted tibial A, Imax, Imin, and J were significantly higher in runners compared with nonrunners. There was no dependence on age. Conclusions: A three-scan densitometric method for measuring cross-sectional structural parameters in long bones in vivo was validated; accuracy and precision measurements establishes confidence limits. From the activity study results, we postulate that higher loads associated with running lead to increased cross-sectional parameters to support axial loads, bending, and torsion in the tibia. C1 Flinders Univ S Australia, Sch Informat & Engn, Adelaide, SA 5001, Australia. NASA, Ames Res Ctr, Musculoskeletal Biomech Lab, Moffett Field, CA USA. RP Cleek, TM (reprint author), Flinders Univ S Australia, Sch Informat & Engn, GPO Box 2100, Adelaide, SA 5001, Australia. EM Tammy.Cleek@flinders.edu.au NR 30 TC 1 Z9 1 U1 1 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3261 USA SN 0195-9131 J9 MED SCI SPORT EXER JI Med. Sci. Sports Exerc. PD OCT PY 2005 VL 37 IS 10 BP 1806 EP 1813 DI 10.1249/01.mss.000018136.81494.58 PG 8 WC Sport Sciences SC Sport Sciences GA 980XM UT WOS:000233051500024 PM 16260985 ER PT J AU Yu, JY Lau, KM AF Yu, JY Lau, KM TI Contrasting Indian Ocean SST variability with and without ENSO influence: A coupled atmosphere-ocean GCM study SO METEOROLOGY AND ATMOSPHERIC PHYSICS LA English DT Article ID GENERAL-CIRCULATION MODEL; PLANETARY BOUNDARY-LAYER; SEA-SURFACE TEMPERATURE; INTERANNUAL VARIABILITY; PACIFIC OCEANS; EL-NINO; DYNAMICS; DIPOLE; PARAMETERIZATION; MONSOON AB In this study, we perform experiments with a coupled atmosphere-ocean general circulation model (CGCM) to examine ENSO's influence on the interannual sea-surface temperature (SST) variability of the tropical Indian Ocean. The control experiment includes both the Indian and Pacific Oceans in the ocean model component of the CGCM (the Indo-Pacific Run). The anomaly experiment excludes ENSO's influence by including only the Indian Ocean while prescribing monthly-varying climatological SSTs for the Pacific Ocean (the Indian-Ocean Run). In the Indo-Pacific Run, an oscillatory mode of the Indian Ocean SST variability is identified by a multi-channel singular spectral analysis (MSSA). The oscillatory mode comprises two patterns that can be identified with the Indian Ocean Zonal Mode (IOZM) and a basin-wide warming/cooling mode respectively. In the model, the IOZM peaks about 3-5 months after ENSO reaches its maximum intensity. The basin mode peaks 8 months after the IOZM. The timing and associated SST patterns suggests that the IOZM is related to ENSO, and the basin-wide warming/cooling develops as a result of the decay of the IOZM spreading SST anomalies from western Indian Ocean to the eastern Indian Ocean. In contrast, in the Indian-Ocean Run, no oscillatory modes can be identified by the MSSA, even though the Indian Ocean SST variability is characterized by east-west SST contrast patterns similar to the IOZM. In both control and anomaly runs, IOZM-like SST variability appears to be associated with forcings from fluctuations of the Indian monsoon. Our modeling results suggest that the oscillatory feature of the IOZM is primarily forced by ENSO. C1 Univ Calif Irvine, Dept Earth Syst Sci, Irvine, CA 92697 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Yu, JY (reprint author), Univ Calif Irvine, Dept Earth Syst Sci, Croul Hall 3315, Irvine, CA 92697 USA. EM jyyu@uci.edu RI Yu, Jin-Yi/G-3413-2011; Lau, William /E-1510-2012 OI Yu, Jin-Yi/0000-0001-6156-7623; Lau, William /0000-0002-3587-3691 NR 40 TC 17 Z9 18 U1 0 U2 3 PU SPRINGER WIEN PI WIEN PA SACHSENPLATZ 4-6, PO BOX 89, A-1201 WIEN, AUSTRIA SN 0177-7971 J9 METEOROL ATMOS PHYS JI Meteorol. Atmos. Phys. PD OCT PY 2005 VL 90 IS 3-4 BP 179 EP 191 DI 10.1007/s00703-004-0094-7 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 977HR UT WOS:000232794500005 ER PT J AU Li, X Sui, CH Lau, KM Tao, WK AF Li, X Sui, CH Lau, KM Tao, WK TI Tropical convective responses to microphysical and radiative processes: a sensitivity study with a 2-D cloud resolving model SO METEOROLOGY AND ATMOSPHERIC PHYSICS LA English DT Article ID WEATHER PREDICTION MODEL; ICE-PHASE MICROPHYSICS; LONG-TERM BEHAVIOR; NUMERICAL-SIMULATION; MICROSCALE STRUCTURE; EXPLICIT SIMULATION; FRONTAL RAINBANDS; SURFACE PROCESSES; WATER-CONTENT; TOGA COARE AB Prognostic cloud schemes are increasingly used in weather and climate models in order to better treat cloud-radiation processes. Simplifications are often made in such schemes for computational efficiency, like the scheme being used in the National Centers for Environment Prediction models that excludes some microphysical processes and precipitation-radiation interaction. In this study, sensitivity tests with a 2-D cloud resolving model are carried out to examine effects of the excluded microphysical processes and precipitation-radiation interaction on tropical thermodynamics and cloud properties. The model is integrated for 10 days with the imposed vertical velocity derived from the Tropical Ocean Global Atmosphere Coupled Ocean-Atmosphere Response Experiment. The experiment excluding the depositional growth of snow from cloud ice shows anomalous growth of cloud ice and more than 20% increase of fractional cloud cover, indicating that the lack of the depositional snow growth causes unrealistically large mixing ratio of cloud ice. The experiment excluding the precipitation-radiation interaction displays a significant cooling and drying bias. The analysis of heat and moisture budgets shows that the simulation without the interaction produces more stable upper troposphere and more unstable mid and lower troposphere than does the simulation with the interaction. Thus, the suppressed growth of ice clouds in upper troposphere and stronger radiative cooling in mid and lower troposphere are responsible for the cooling bias, and less evaporation of rain associated with the large-scale subsidence induces the drying in mid and lower troposphere. C1 NOAA, NESDIS, ORA, Camp Springs, MD 20746 USA. Joint Ctr Satellite Data Assimilat, Camp Springs, MD 20746 USA. Natl Cent Univ, Inst Hydrol Sci, Chungli 32054, Taiwan. NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. RP Li, X (reprint author), NOAA, NESDIS, ORA, 5200 Auth Rd,Room 711, Camp Springs, MD 20746 USA. EM xiaofan.li@noaa.gov RI Li, Xiaofan/F-5605-2010; Li, Xiaofan/G-2094-2014; Lau, William /E-1510-2012; OI Lau, William /0000-0002-3587-3691; SUI, CHUNG-HSIUNG/0000-0003-2842-5660 NR 40 TC 19 Z9 20 U1 0 U2 2 PU SPRINGER WIEN PI VIENNA PA SACHSENPLATZ 4-6, PO BOX 89, A-1201 VIENNA, AUSTRIA SN 0177-7971 J9 METEOROL ATMOS PHYS JI Meteorol. Atmos. Phys. PD OCT PY 2005 VL 90 IS 3-4 BP 245 EP 259 DI 10.1007/s00703-004-0088-5 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 977HR UT WOS:000232794500010 ER PT J AU Page, KL Rol, E Levan, AJ Zhang, B Osborne, JP O'Brien, PT Beardmore, AP Burrows, DN Campana, S Chincharini, G Cummings, JR Cusumano, G Gehrels, N Giommi, P Goad, MR Godet, O Mangano, V Tagliaferri, G Wells, AA AF Page, K. L. Rol, E. Levan, A. J. Zhang, B. Osborne, J. P. O'Brien, P. T. Beardmore, A. P. Burrows, D. N. Campana, S. Chincharini, G. Cummings, J. R. Cusumano, G. Gehrels, N. Giommi, P. Goad, M. R. Godet, O. Mangano, V. Tagliaferri, G. Wells, A. A. TI GRB 050223: a faint gamma-ray burst discovered by Swift SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE gamma-rays: bursts ID LIGHT CURVES; SPECTRA; AFTERGLOWS; TELESCOPE; JETS; MISSION AB GRB 050223 was discovered by the Swift Gamma-Ray Burst Explorer on 2005 February 23 and was the first gamma-ray burst (GRB) to be observed by both Swift and XMM-Newton. At the time of writing (2005 May), it has one of the faintest GRB afterglows ever observed. The spacecraft could not slew immediately to the burst, so the first X-ray and optical observations occurred approximately 45 min after the trigger. Although no optical emission was found by any instrument, both Swift and XMM-Newton detected the fading X-ray afterglow. Combined data from both of these observatories show the afterglow to be fading monotonically as 0.99(-0.12)(+0.15) over a time-frame between 45 min and 27 h post-burst. Spectral analysis, allowed largely by the higher throughput of XMM-Newton, implies a power law with a slope of Gamma = 1.75(-0.18)(+0.19) and shows no evidence for absorption above the Galactic column of 7 x 1020 cm(-2). From the X-ray decay and spectral slopes, a low electron power-law index of p = 1.3-1.9 is derived; the slopes also imply that a jet-break has not occurred up to 27 h after the burst. The faintness of GRB 050223 may be due to a large jet opening or viewing angle or a high redshift. C1 [Page, K. L.; Rol, E.; Levan, A. J.; Osborne, J. P.; O'Brien, P. T.; Beardmore, A. P.; Goad, M. R.; Godet, O.; Wells, A. A.] Univ Leicester, Dept Phys & Astron, Xray & Observat Astron Grp, Leicester LE1 7RH, Leics, England. [Zhang, B.] Univ Nevada, Las Vegas, NV 89154 USA. [Burrows, D. N.] Penn State Univ, Davey Lab 525, Dept Phys & Astron, University Pk, PA 16802 USA. [Campana, S.; Chincharini, G.; Tagliaferri, G.] Osserv Astron Brera, INAF, I-23807 Merate, Italy. [Chincharini, G.] Univ Milano Bicocca, Dipartimento Fis, I-20126 Milan, Italy. [Cummings, J. R.; Gehrels, N.; Mangano, V.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. [Cusumano, G.] Ist Astrofis Spaziale, INAF, I-90146 Palermo, Italy. [Cusumano, G.] Fis Cosm Sez Palermo, I-90146 Palermo, Italy. [Giommi, P.] ASI Sci Data Ctr, I-00044 Frascati, Italy. RP Page, KL (reprint author), Univ Leicester, Dept Phys & Astron, Xray & Observat Astron Grp, Leicester LE1 7RH, Leics, England. EM kpa@star.le.ac.uk RI Gehrels, Neil/D-2971-2012; OI Campana, Sergio/0000-0001-6278-1576; giommi, paolo/0000-0002-2265-5003; Cusumano, Giancarlo/0000-0002-8151-1990; Tagliaferri, Gianpiero/0000-0003-0121-0723 FU Particle Physics and Astronomy Research Council (PPARC), at Penn State by NASA [NAS5-00136]; ASI [I/R/039/04]; National Research Council FX We thank Don Lamb for useful comments on the paper, and Jochen Greiner for his GRB afterglows website. This work is supported at the University of Leicester by the Particle Physics and Astronomy Research Council (PPARC), at Penn State by NASA contract NAS5-00136 and in Italy by funding from ASI (contract number I/R/039/04). JRC is supported by a National Research Council Associateship award at NASA's Goddard Space Flight Center. NR 39 TC 5 Z9 5 U1 0 U2 0 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD OCT PY 2005 VL 363 IS 1 BP L76 EP L80 DI 10.1111/j.1745-3933.2005.00086.x PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA V16ZA UT WOS:000207906300016 ER PT J AU Ibragimov, A Poutanen, J Gilfanov, M Zdziarski, AA Shrader, CR AF Ibragimov, A Poutanen, J Gilfanov, M Zdziarski, AA Shrader, CR TI Broad-band spectra of Cygnus X-1 and correlations between spectral characteristics SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE accretion, accretion discs; black hole physics; stars : individual : Cygnus X-1; gamma-rays : observations; X-rays : binaries ID X-RAY BINARIES; ACCRETION DISK MODELS; BLACK-HOLE; COMPTON REFLECTION; IRON LINE; TEMPORAL CORRELATIONS; HARD STATE; CYG X-1; VARIABILITY; CORONAE AB We present the results of the spectral analysis of 42 simultaneous broad-band Ginga-OSSE and RXTE-OSSE observations of Cygnus X-1 carried out in 1991 and 1996-1999. The broad-band spectra from 3 to similar to 1000 keV can be well described by the thermal Comptonization model with reflection from the cold disc, with an additional soft component visible below 10 keV. The relative contribution of this component to the total energy flux appears to be higher in the spectra with larger reflection amplitude and steeper photon index of the thermal Comptonized component. We consider a number of physically realistic models to describe the shape of the E similar to 10 keV excess. The additional soft component can result from thermal Comptonization by electrons with a low Compton parameter, or can be a part of a non-thermal, power-law-like emission extending above 1 MeV. We study correlations between parameters obtained from the spectral fits with different models. We confirm a general correlation between the photon index Gamma and the amplitude of reflection R. We find that simple phenomenological models ( such as power law plus Compton reflection) applied to the narrow band (3-20 keV) data overestimated the values of R and Gamma, although the simple models did rank correctly the spectra according to R and Gamma, as demonstrated in the original publications on this subject. The dynamic corona model provides a satisfactory description of the observed correlation, while the hot inner disc models have problems in reproducing it quantitatively. On the other hand, in the context of the dynamic corona model it is difficult to understand correlations with the timing characteristics, which seems natural in the hot disc scenario. We do not find significant correlation between the electron temperature and other spectral parameters, while the optical depth of the hot medium seems to decrease when the spectrum becomes softer. It is also shown that spectral parameters are well correlated with the timing characteristics of the source. C1 Univ Oulu, Astron Div, FIN-90014 Oulu, Finland. Kazan VI Lenin State Univ, Dept Astron, Kazan 420008, Russia. Max Planck Inst Astrophys, D-85740 Garching, Germany. Russian Acad Sci, Inst Space Res, Moscow 117810, Russia. Cent Astron M Kopernika, PL-00716 Warsaw, Poland. NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. RP Ibragimov, A (reprint author), Univ Oulu, Astron Div, POB 3000, FIN-90014 Oulu, Finland. EM askar.ibragimov@oulu.fi; juri.poutanen@oulu.fi RI Poutanen, Juri/H-6651-2016 OI Poutanen, Juri/0000-0002-0983-0049 NR 63 TC 58 Z9 58 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 OCT 1 PY 2005 VL 362 IS 4 BP 1435 EP 1450 DI 10.1111/j.1365-2966.2005.09415.x PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 964TP UT WOS:000231903800030 ER PT J AU Guillen-Gonzalez, F Rodriguez-Gomez, D AF Guillen-Gonzalez, F Rodriguez-Gomez, D TI Bubble finite elements for the primitive equations of the ocean SO NUMERISCHE MATHEMATIK LA English DT Article ID NAVIER-STOKES EQUATIONS; HYDROSTATIC APPROXIMATION; INTERPOLATION; OCEANOGRAPHY AB We introduce in this paper two original Mixed methods for the numerical resolution of the (stationary) Primitive Equations (PE) of the Ocean. The PE govern the behavior of oceanic flows in shallow domains for large time scales. We use a reduced formulation (Lions et al. [28]) involving horizontal velocities and surface pressures. By using bubble functions constructed ad-hoc, we are able to define two stable Mixed Methods requiring a low number of degrees of freedom. The first one is based on the addition of bubbles of reduced support to P-1(x) circle times P-1(z) velocities elementwise. The second one makes use of conic bubbles of extended support along the vertical coordinate. The latter constitutes a genuine mini-element for the PE, e.g., it requires the least number of extra degrees of freedom to stabilize piecewise linear hydrostatic pressures. Both methods verify a specific inf-sup condition and provide stability and convergence. Finally, we compare several numerical features of the proposed pairs in the context of other FE methods found in the literature. C1 Univ Sevilla, Dept EDAN, E-41080 Seville, Spain. NASA, Ames Res Ctr, Exobiol Branch, Moffett Field, CA 94035 USA. RP Guillen-Gonzalez, F (reprint author), Univ Sevilla, Dept EDAN, Apto 1160, E-41080 Seville, Spain. EM guillen@us.es; dgomez@templar.arc.nasa.gov RI Guillen Gonzalez, Francisco Manuel/H-1477-2015 OI Guillen Gonzalez, Francisco Manuel/0000-0001-5539-5888 NR 38 TC 5 Z9 5 U1 1 U2 2 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 0029-599X J9 NUMER MATH JI Numer. Math. PD OCT PY 2005 VL 101 IS 4 BP 689 EP 728 DI 10.1007/s00211-005-0626-1 PG 40 WC Mathematics, Applied SC Mathematics GA 973NY UT WOS:000232531100006 ER PT J AU Barnes, NP AF Barnes, NP TI Compositionally tuned lasers: Practical lasers at designer wavelengths SO OPTICAL MATERIALS LA English DT Article; Proceedings Paper CT 2nd International Workshop on Photonic and Electronic Materials CY JUN 14-16, 2004 CL San Sebastian, SPAIN SP Donostia Int Phys Ctr AB A general need exists for practical solid state lasers at particular wavelengths. For NASA, these particular wavelengths are needed for remote sensing of atmospheric constituents such as water vapor and green house gasses. Transition metal solid state lasers can be widely tuned, however, they usually possess a relatively short upper laser level lifetime or a relatively small emission cross section. Either of these parameters can limit the practicality of transition metal lasers. On the other hand, lanthanide series solid state lasers have attractive upper laser level lifetimes and emission cross sections, however they have narrow tuning ranges. This problem is solved by utilizing the concept of compositional tuning of lanthanide series lasers. Compositional tuning effects, including the tuning range, are predicted using quantum mechanical calculations. They are also experimentally verified by means of spectroscopic measurements. Practical examples for two lanthanide series lasers that were compositionally tuned to a preselected water vapor absorption feature are presented. Both flash lamp pumped and diode pumped laser results are presented. (c) 2005 Elsevier B.V. All rights reserved. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Barnes, NP (reprint author), NASA, Langley Res Ctr, Hampton, VA 23681 USA. NR 1 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0925-3467 J9 OPT MATER JI Opt. Mater. PD OCT PY 2005 VL 27 IS 11 BP 1653 EP 1657 DI 10.1016/j.optmat.2004.11.053 PG 5 WC Materials Science, Multidisciplinary; Optics SC Materials Science; Optics GA 965QP UT WOS:000231965700003 ER PT J AU Nna-Mvondo, D Navarro-Gonzalez, R Raulin, F Coll, P AF Nna-Mvondo, D Navarro-Gonzalez, R Raulin, F Coll, P TI Nitrogen fixation by corona discharge on the early precambrian Earth SO ORIGINS OF LIFE AND EVOLUTION OF THE BIOSPHERE LA English DT Article DE corona discharge; energy yield; experimental simulation; nitric oxide; nitrogen fixation; nitrous oxide; primitive Earth ID CHEMICAL EVOLUTION; FIELD-MEASUREMENTS; EARLY ATMOSPHERE; OXIDE PRODUCTION; ENERGY; METHANE; N2O; PHOTOCHEMISTRY; DEPENDENCE; REDUCTION AB We report the first experimental study of nitrogen fixation by corona discharge on the anoxic primitive Earth. The energy yields of nitric oxide (NO) and nitrous oxide (N2O) were experimentally determined over a wide range Of CO2-N-2 mixtures simulating the evolution of the Earth's atmosphere during the Hadean and Archean eras (from 4.5 ba to 2.5 ba). NO, the principal form of fixed nitrogen in lightning and coronal discharge in early Earth, is produced ten times less efficiently in the latter type of electrical discharge with an estimated maximum annual production rate of the order of 10(10) g yr(-1). For N2O the maximum production rate was estimated to be similar to 10(9) g yr(-1). These low rates of syntheses indicate that corona discharges as point discharges on the clouds and ground did not play a significant role in the overall pool of reactive nitrogen needed for the emergence and sustainability of life. C1 Univ Autonoma Mexico, Lab Quim Plasmas & Estudios Planetarios, Inst Ciencias Nucl, Mexico City 04510, DF, Mexico. Univ Paris 12, Lab Interuniv Syst Atmospher, UMR CNRS 7583, F-94010 Creteil, France. Univ Paris 07, Lab Interuniv Syst Atmospher, UMR CNRS 7583, F-94010 Creteil, France. RP Nna-Mvondo, D (reprint author), NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA. EM dnnamvondo@mail.arc.nasa.gov RI Gonzalez, Rafael/D-1748-2009 NR 33 TC 17 Z9 17 U1 2 U2 9 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0169-6149 J9 ORIGINS LIFE EVOL B JI Orig. Life Evol. Biosph. PD OCT PY 2005 VL 35 IS 5 BP 401 EP 409 DI 10.1007/s11084-005-1972-9 PG 9 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 014ZB UT WOS:000235520600001 PM 16231204 ER PT J AU Weber, AL AF Weber, AL TI Aqueous synthesis of peptide thioesters from amino acids and a thiol using 1,1 '-carbonyldiimidazole SO ORIGINS OF LIFE AND EVOLUTION OF THE BIOSPHERE LA English DT Article DE aqueous thioester synthesis; carbonyldiimidazole; origin of life; peptide; peptide thioester; thioester ID SELF-REPLICATING PEPTIDE; NATIVE CHEMICAL LIGATION; GLYCERALDEHYDE AB A new method was developed for the synthesis of peptide thioesters from free amino acids and thiols in water. This one-pot simple method involves two steps: (1) activation in water of an amino acid presumably as its N-carboxyanhydride (NCA) using 1,1'-carbonyldiimidazole (CDI), and (2) subsequent condensation of the activated amino acid-NCA in the presence of a thiol. With this method citrulline peptide thioesters containing up to 10 amino acid residues were prepared in a single reaction. This aqueous synthetic method provides a simple way to prepare peptide thioesters for studies of peptide replication involving ligation of peptide thioesters on peptide templates. The relevance of peptide replication to the origin-of-life process is supported by previous studies showing that amino acid thioesters (peptide thioester precursors) can be synthesized under prebiotic conditions by reaction of small sugars with ammonia and a thiol. C1 NASA, Ames Res Ctr, SETI Inst, Moffett Field, CA 94035 USA. RP Weber, AL (reprint author), NASA, Ames Res Ctr, SETI Inst, Mail Stop 239-4, Moffett Field, CA 94035 USA. EM aweber@mail.arc.nasa.gov NR 15 TC 15 Z9 16 U1 4 U2 18 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0169-6149 J9 ORIGINS LIFE EVOL B JI Orig. Life Evol. Biosph. PD OCT PY 2005 VL 35 IS 5 BP 421 EP 427 DI 10.1007/s11084-005-4070-0 PG 7 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 014ZB UT WOS:000235520600003 PM 16231206 ER PT J AU Ierotheou, CS Jin, H Matthews, G Johnson, SP Hood, R AF Ierotheou, CS Jin, H Matthews, G Johnson, SP Hood, R TI Generating OpenMP code using an interactive parallelization environment SO PARALLEL COMPUTING LA English DT Article DE interactive parallelization environment; OpenMP code generation; parallel debugger; code parallelization tools AB Code parallelization using OpenMP for shared memory systems is relatively easier than using message passing for distributed memory systems. Despite this, it is still a challenge to use OpenMP to parallelize application codes in a way that yields effective scalable performance when executed on a shared memory parallel system. We describe an environment that will assist the programmer in the various tasks of code parallelization and this is achieved in a greatly reduced time frame and level of skill required. The parallelization. environment includes a number of tools that address the main tasks of parallelism detection, OpenMP source code generation, debugging and optimization. These tools include a high quality, fully interprocedural dependence analysis with user interaction capabilities to facilitate the generation of efficient parallel code, an automatic relative debugging tool to identify erroneous user decisions in that interaction and also performance profiling to identify bottlenecks. Finally, experiences of parallelizing some NASA application codes are presented to illustrate some of the benefits of using the evolving environment. Published by Elsevier B.V. C1 Univ Greenwich, Parallel Proc Res Grp, London SE10 9LS, England. NASA, Ames Res Ctr, Adv Supercomp Div, Moffett Field, CA 94035 USA. RP Ierotheou, CS (reprint author), Univ Greenwich, Parallel Proc Res Grp, London SE10 9LS, England. EM c.ierotheou@gre.ac.uk NR 20 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-8191 J9 PARALLEL COMPUT JI Parallel Comput. PD OCT-DEC PY 2005 VL 31 IS 10-12 BP 999 EP 1012 DI 10.1016/j.parco.2005.03.008 PG 14 WC Computer Science, Theory & Methods SC Computer Science GA 991VA UT WOS:000233841000004 ER PT J AU Li, RX Squyres, SW Arvidson, RE Archinal, BA Bell, J Cheng, Y Crumpler, L Marais, DJD Di, K Ely, TA Golombek, M Graat, E Grant, J Guinn, J Johnson, A Greeley, R Kirk, RL Maimone, M Matthies, LH Malin, M Parker, T Sims, M Soderblom, LA Thompson, S Wang, J Whelley, P Xu, FL AF Li, RX Squyres, SW Arvidson, RE Archinal, BA Bell, J Cheng, Y Crumpler, L Marais, DJD Di, K Ely, TA Golombek, M Graat, E Grant, J Guinn, J Johnson, A Greeley, R Kirk, RL Maimone, M Matthies, LH Malin, M Parker, T Sims, M Soderblom, LA Thompson, S Wang, J Whelley, P Xu, FL TI Initial results of rover localization and topographic mapping for the 2003 mars exploration rover mission SO PHOTOGRAMMETRIC ENGINEERING AND REMOTE SENSING LA English DT Article ID GUSEV CRATER; ORBITER CAMERA; LANDING SITES; SPIRIT ROVER AB This paper presents the initial results of lander and rover localization and topographic mapping of the MER 2003 mission (by Sol 225 for Spirit and Sol 206 for Opportunity). The Spirit rover has traversed a distance of 3.2 km (actual distance traveled instead of odometry) and Opportunity ut 1.2 km. We localized the landers in the Gusev Crater and on the Meridiani Planum using two-way Doppler radio positioning technology and cartographic triangulations through landmarks visible in both orbital and ground images. Additional high-resolution orbital images were taken to verify the determined lander positions. Visual odometry and bundle-adjustment technologies were applied to overcome wheel slippages, azimuthal angle drift and other navigation errors (as large as 21 percent). We generated timely topographic products including 68 orthophoto mops and 3D Digital Terrain Models, eight horizontal rover traverse maps, vertical traverse profiles up to Sol 214 for Spirit and Sol 62 for Opportunity, and five 3D crater models. A web-based landing-site Geographic Information System (GIS) has been set up at The Ohio State University to update and disseminate the daily localization and topographic information to support tactical and strategic operations of the mission. Also described in this paper are applications of the data for science operations planning, geological traverse survey, survey of wind-related features, and other science applications. The majority of the instruments onboard both rovers are healthy at this moment, and they will continue to explore the two landing sites on the Martian surface. We expect to report further localization and topographic mapping results to be achieved in the rest of the mission period and in post-mission data processing. C1 Ohio State Univ, Dept Civil & Environm Engn & Geodet Sci, Columbus, OH 43210 USA. Cornell Univ, Ithaca, NY USA. Washington Univ, St Louis, MO USA. CALTECH, Jet Prop Lab, Pasadena, CA USA. New Mexico Museum Atural Hist & Sci, Albuquerque, NM USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Smithsonian Inst, Washington, DC 20560 USA. Arizona State Univ, Tempe, AZ USA. US Geol Survey, Flagstaff, AZ 86001 USA. Malin Space Sci Syst, San Diego, CA USA. RP Ohio State Univ, Dept Civil & Environm Engn & Geodet Sci, Columbus, OH 43210 USA. EM li282@osu.edu RI Wang, Jue/C-9215-2009; Whelley, Patrick/B-9560-2012 OI Wang, Jue/0000-0002-9901-9996; Whelley, Patrick/0000-0003-3266-9772 NR 34 TC 33 Z9 41 U1 3 U2 8 PU AMER SOC PHOTOGRAMMETRY PI BETHESDA PA 5410 GROSVENOR LANE SUITE 210, BETHESDA, MD 20814-2160 USA SN 0099-1112 EI 2374-8079 J9 PHOTOGRAMM ENG REM S JI Photogramm. Eng. Remote Sens. PD OCT PY 2005 VL 71 IS 10 BP 1129 EP 1142 PG 14 WC Geography, Physical; Geosciences, Multidisciplinary; Remote Sensing; Imaging Science & Photographic Technology SC Physical Geography; Geology; Remote Sensing; Imaging Science & Photographic Technology GA 972TL UT WOS:000232476000004 ER PT J AU Ansar, A Cheng, Y AF Ansar, A Cheng, Y TI An analysis of spacecraft localization from descent image data for pinpoint landing on mars and other cratered bodies SO PHOTOGRAMMETRIC ENGINEERING AND REMOTE SENSING LA English DT Article ID POSE ESTIMATION AB A pinpoint landing capability will be a critical component for many planned NASA missions to Mars and beyond. Implicit in the requirement is the ability to accurately localize the spacecraft with respect to the terrain during descent. In this paper, we present evidence that a vision-based solution using craters as landmarks is both practical and will meet the requirements of next generation missions. Our emphasis in this paper is on the feasibility of such a system in terms of (a) localization accuracy and (b) applicability to Martian terrain. We show that accuracy of well under 100 meters can be expected under suitable conditions. We also present a sensitivity analysis that makes an explicit connection between input data and robustness of our pose estimate. In addition, we present an analysis of the susceptibility of our technique to inherently ambiguous configurations of craters. We show that probability of failure due to such ambiguity is becoming increasingly small. C1 CALTECH, Jet Prop Lab, NASA, Pasadena, CA 91109 USA. RP Ansar, A (reprint author), CALTECH, Jet Prop Lab, NASA, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM ansar@jpl.nasa.gov; ycheng@jpl.nasa.gov NR 10 TC 4 Z9 8 U1 0 U2 1 PU AMER SOC PHOTOGRAMMETRY PI BETHESDA PA 5410 GROSVENOR LANE SUITE 210, BETHESDA, MD 20814-2160 USA SN 0099-1112 J9 PHOTOGRAMM ENG REM S JI Photogramm. Eng. Remote Sens. PD OCT PY 2005 VL 71 IS 10 BP 1197 EP 1204 PG 8 WC Geography, Physical; Geosciences, Multidisciplinary; Remote Sensing; Imaging Science & Photographic Technology SC Physical Geography; Geology; Remote Sensing; Imaging Science & Photographic Technology GA 972TL UT WOS:000232476000010 ER PT J AU Maslov, AV Ning, CZ AF Maslov, AV Ning, CZ TI Radius-dependent polarization anisotropy in semiconductor nanowires SO PHYSICAL REVIEW B LA English DT Article ID CENTER-DOT-P; QUANTUM-WELL WIRES; OPTICAL-ABSORPTION; ELECTRON-STRUCTURE AB Polarization anisotropy in semiconductor nanowires is studied using the standard eight-band k center dot p theory. We show that the anisotropy ratio ranges from giant (similar to 90%) to moderate (similar to 60%) for the nanowire radius between 3 and 10 nm. Our result resolves an apparent contradiction between a recent tight-binding study [M. P. Persson and H. Q. Xu, Phys. Rev. B 70, 161310(R) (2004)], which predicts 100% anisotropy, and an earlier k center dot p study [P. C. Sercel and K. J. Vahala, Phys. Rev. B 44, 5681 (1991)], which predicts 60% anisotropy independent of radius. We show that with proper inclusion of band mixing, the k center dot p theory agrees well with the tight-binding study on anisotropy. C1 NASA, Ctr Nanotechnol, Ames Res Ctr, Moffett Field, CA 94035 USA. RP NASA, Ctr Nanotechnol, Ames Res Ctr, Mail Stop 229-1, Moffett Field, CA 94035 USA. RI Maslov, Alexey/E-5158-2011; Ning, C. Z./D-4699-2009 OI Maslov, Alexey/0000-0002-7835-2474; Ning, C. Z./0000-0003-4583-8889 NR 18 TC 19 Z9 19 U1 1 U2 6 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD OCT PY 2005 VL 72 IS 16 AR 161310 DI 10.1103/PhysRevB.72.161310 PG 4 WC Physics, Condensed Matter SC Physics GA 979IF UT WOS:000232934900014 ER PT J AU Abbott, B Abbott, R Adhikari, R Ageev, A Allen, B Amin, R Anderson, SB Anderson, WG Araya, M Armandula, H Ashley, M Asiri, F Aufmuth, P Aulbert, C Babak, S Balasubramanian, R Ballmer, S Barish, BC Barker, C Barker, D Barnes, M Barr, B Barton, MA Bayer, K Beausoleil, R Belczynski, K Bennett, R Berukoff, SJ Betzwieser, J Bhawal, B Bilenko, IA Billingsley, G Black, E Blackburn, K Blackburn, L Bland, B Bochner, B Bogue, L Bork, R Bose, S Brady, PR Braginsky, VB Brau, JE Brown, DA Bullington, A Bunkowski, A Buonanno, A Burgess, R Busby, D Butler, WE Byer, RL Cadonati, L Cagnoli, G Camp, JB Cantley, CA Cardenas, L Carter, K Casey, MM Castiglione, J Chandler, A Chapsky, J Charlton, P Chatterji, S Chelkowski, S Chen, Y Chickarmane, V Chin, D Christensen, N Churches, D Cokelaer, T Colacino, C Coldwell, R Coles, M Cook, D Corbitt, T Coyne, D Creighton, JDE Creighton, TD Crooks, DRM Csatorday, P Cusack, BJ Cutler, C D'Ambrosio, E Danzmann, K Daw, E DeBra, D Delker, T Dergachev, V DeSalvo, R Dhurandhar, S Di Credico, A Diaz, M Ding, H Drever, RWP Dupuis, RJ Edlund, JA Ehrens, P Elliffe, EJ Etzel, T Evans, M Evans, T Fairhurst, S Fallnich, C Farnham, D Fejer, MM Findley, T Fine, M Finn, LS Franzen, KY Freise, A Frey, R Fritschel, P Frolov, VV Fyffe, M Ganezer, KS Garofoli, J Giaime, JA Gillespie, A Goda, K Gonzalez, G Gossler, S Grandclement, P Grant, A Gray, C Gretarsson, AM Grimmett, D Grote, H Grunewald, S Guenther, M Gustafson, E Gustafson, R Hamilton, WO Hammond, M Hanson, J Hardham, C Harms, J Harry, G Hartunian, A Heefner, J Hefetz, Y Heinzel, G Heng, IS Hennessy, M Hepler, N Heptonstall, A Heurs, M Hewitson, M Hild, S Hindman, N Hoang, P Hough, J Hrynevych, M Hua, W Ito, M Itoh, Y Ivanov, A Jennrich, O Johnson, B Johnson, WW Johnston, WR Jones, DI Jones, L Jungwirth, D Kalogera, V Katsavounidis, E Kawabe, K Kawamura, S Kells, W Kern, J Khan, A Killbourn, S Killow, CJ Kim, C King, C King, P Klimenko, S Koranda, S Kotter, K Kovalik, J Kozak, D Krishnan, B Landry, M Langdale, J Lantz, B Lawrence, R Lazzarini, A Lei, M Leonor, I Libbrecht, K Libson, A Lindquist, P Liu, S Logan, J Lormand, M Lubinski, M Luck, H Lyons, TT Machenschalk, B MacInnis, M Mageswaran, M Mailand, K Majid, W Malec, M Mann, F Marin, A Marka, S Maros, E Mason, J Mason, K Matherny, O Matone, L Mavalvala, N McCarthy, R McClelland, DE McHugh, M McNabb, JWC Mendell, G Mercer, RA Meshkov, S Messaritaki, E Messenger, C Mitrofanov, VP Mitselmakher, G Mittleman, R Miyakawa, O Miyoki, S Mohanty, S Moreno, G Mossavi, K Mueller, G Mukherjee, S Murray, P Myers, J Nagano, S Nash, T Nayak, R Newton, G Nocera, F Noel, JS Nutzman, P Olson, T O'Reilly, B Ottaway, DJ Ottewill, A Ouimette, D Overmier, H Owen, BJ Pan, Y Papa, MA Parameshwaraiah, V Parameswaran, A Parameswariah, C Pedraza, M Penn, S Pitkin, M Plissi, M Prix, R Quetschke, V Raab, F Radkins, H Rahkola, R Rakhmanov, M Rao, SR Rawlins, K Ray-Majumder, S Re, V Redding, D Regehr, MW Regimbau, T Reid, S Reilly, KT Reithmaier, K Reitze, DH Richman, S Riesen, R Riles, K Rivera, B Rizzi, A Robertson, DI Robertson, NA Robison, L Roddy, S Rollins, J Romano, JD Romie, J Rong, H Rose, D Rotthoff, E Rowan, S Rudiger, A Russell, P Ryan, K Salzman, I Sandberg, V Sanders, GH Sannibale, V Sathyaprakash, B Saulson, PR Savage, R Sazonov, A Schilling, R Schlaufman, K Schmidt, V Schnabel, R Schofield, R Schutz, BF Schwinberg, P Scott, SM Seader, SE Searle, AC Sears, B Seel, S Seifert, F Sengupta, AS Shapiro, CA Shawhan, P Shoemaker, DH Shu, QZ Sibley, A Siemens, X Sievers, L Sigg, D Sintes, AM Smith, JR Smith, M Smith, MR Sneddon, PH Spero, R Stapfer, G Steussy, D Strain, KA Strom, D Stuver, A Summerscales, T Sumner, MC Sutton, PJ Sylvestre, J Takamori, A Tanner, DB Tariq, H Taylor, I Taylor, R Taylor, R Thorne, KA Thorne, KS Tibbits, M Tilav, S Tinto, M Tokmakov, KV Torres, C Torrie, C Traylor, G Tyler, W Ugolini, D Ungarelli, C Vallisneri, M van Putten, M Vass, S Vecchio, A Veitch, J Vorvick, C Vyachanin, SP Wallace, L Walther, H Ward, H Ware, B Watts, K Webber, D Weidner, A Weiland, U Weinstein, A Weiss, R Welling, H Wen, L Wen, S Whelan, JT Whitcomb, SE Whiting, BF Wiley, S Wilkinson, C Willems, PA Williams, PR Williams, R Willke, B Wilson, A Winjum, BJ Winkler, W Wise, S Wiseman, AG Woan, G Woods, D Wooley, R Worden, J Wu, W Yakushin, I Yamamoto, H Yoshida, S Zaleski, KD Zanolin, M Zawischa, I Zhang, L Zhu, R Zotov, N Zucker, M Zweizig, J AF Abbott, B Abbott, R Adhikari, R Ageev, A Allen, B Amin, R Anderson, SB Anderson, WG Araya, M Armandula, H Ashley, M Asiri, F Aufmuth, P Aulbert, C Babak, S Balasubramanian, R Ballmer, S Barish, BC Barker, C Barker, D Barnes, M Barr, B Barton, MA Bayer, K Beausoleil, R Belczynski, K Bennett, R Berukoff, SJ Betzwieser, J Bhawal, B Bilenko, IA Billingsley, G Black, E Blackburn, K Blackburn, L Bland, B Bochner, B Bogue, L Bork, R Bose, S Brady, PR Braginsky, VB Brau, JE Brown, DA Bullington, A Bunkowski, A Buonanno, A Burgess, R Busby, D Butler, WE Byer, RL Cadonati, L Cagnoli, G Camp, JB Cantley, CA Cardenas, L Carter, K Casey, MM Castiglione, J Chandler, A Chapsky, J Charlton, P Chatterji, S Chelkowski, S Chen, Y Chickarmane, V Chin, D Christensen, N Churches, D Cokelaer, T Colacino, C Coldwell, R Coles, M Cook, D Corbitt, T Coyne, D Creighton, JDE Creighton, TD Crooks, DRM Csatorday, P Cusack, BJ Cutler, C D'Ambrosio, E Danzmann, K Daw, E DeBra, D Delker, T Dergachev, V DeSalvo, R Dhurandhar, S Di Credico, A Diaz, M Ding, H Drever, RWP Dupuis, RJ Edlund, JA Ehrens, P Elliffe, EJ Etzel, T Evans, M Evans, T Fairhurst, S Fallnich, C Farnham, D Fejer, MM Findley, T Fine, M Finn, LS Franzen, KY Freise, A Frey, R Fritschel, P Frolov, VV Fyffe, M Ganezer, KS Garofoli, J Giaime, JA Gillespie, A Goda, K Gonzalez, G Gossler, S Grandclement, P Grant, A Gray, C Gretarsson, AM Grimmett, D Grote, H Grunewald, S Guenther, M Gustafson, E Gustafson, R Hamilton, WO Hammond, M Hanson, J Hardham, C Harms, J Harry, G Hartunian, A Heefner, J Hefetz, Y Heinzel, G Heng, IS Hennessy, M Hepler, N Heptonstall, A Heurs, M Hewitson, M Hild, S Hindman, N Hoang, P Hough, J Hrynevych, M Hua, W Ito, M Itoh, Y Ivanov, A Jennrich, O Johnson, B Johnson, WW Johnston, WR Jones, DI Jones, L Jungwirth, D Kalogera, V Katsavounidis, E Kawabe, K Kawamura, S Kells, W Kern, J Khan, A Killbourn, S Killow, CJ Kim, C King, C King, P Klimenko, S Koranda, S Kotter, K Kovalik, J Kozak, D Krishnan, B Landry, M Langdale, J Lantz, B Lawrence, R Lazzarini, A Lei, M Leonor, I Libbrecht, K Libson, A Lindquist, P Liu, S Logan, J Lormand, M Lubinski, M Luck, H Lyons, TT Machenschalk, B MacInnis, M Mageswaran, M Mailand, K Majid, W Malec, M Mann, F Marin, A Marka, S Maros, E Mason, J Mason, K Matherny, O Matone, L Mavalvala, N McCarthy, R McClelland, DE McHugh, M McNabb, JWC Mendell, G Mercer, RA Meshkov, S Messaritaki, E Messenger, C Mitrofanov, VP Mitselmakher, G Mittleman, R Miyakawa, O Miyoki, S Mohanty, S Moreno, G Mossavi, K Mueller, G Mukherjee, S Murray, P Myers, J Nagano, S Nash, T Nayak, R Newton, G Nocera, F Noel, JS Nutzman, P Olson, T O'Reilly, B Ottaway, DJ Ottewill, A Ouimette, D Overmier, H Owen, BJ Pan, Y Papa, MA Parameshwaraiah, V Parameswaran, A Parameswariah, C Pedraza, M Penn, S Pitkin, M Plissi, M Prix, R Quetschke, V Raab, F Radkins, H Rahkola, R Rakhmanov, M Rao, SR Rawlins, K Ray-Majumder, S Re, V Redding, D Regehr, MW Regimbau, T Reid, S Reilly, KT Reithmaier, K Reitze, DH Richman, S Riesen, R Riles, K Rivera, B Rizzi, A Robertson, DI Robertson, NA Robison, L Roddy, S Rollins, J Romano, JD Romie, J Rong, H Rose, D Rotthoff, E Rowan, S Rudiger, A Russell, P Ryan, K Salzman, I Sandberg, V Sanders, GH Sannibale, V Sathyaprakash, B Saulson, PR Savage, R Sazonov, A Schilling, R Schlaufman, K Schmidt, V Schnabel, R Schofield, R Schutz, BF Schwinberg, P Scott, SM Seader, SE Searle, AC Sears, B Seel, S Seifert, F Sengupta, AS Shapiro, CA Shawhan, P Shoemaker, DH Shu, QZ Sibley, A Siemens, X Sievers, L Sigg, D Sintes, AM Smith, JR Smith, M Smith, MR Sneddon, PH Spero, R Stapfer, G Steussy, D Strain, KA Strom, D Stuver, A Summerscales, T Sumner, MC Sutton, PJ Sylvestre, J Takamori, A Tanner, DB Tariq, H Taylor, I Taylor, R Taylor, R Thorne, KA Thorne, KS Tibbits, M Tilav, S Tinto, M Tokmakov, KV Torres, C Torrie, C Traylor, G Tyler, W Ugolini, D Ungarelli, C Vallisneri, M van Putten, M Vass, S Vecchio, A Veitch, J Vorvick, C Vyachanin, SP Wallace, L Walther, H Ward, H Ware, B Watts, K Webber, D Weidner, A Weiland, U Weinstein, A Weiss, R Welling, H Wen, L Wen, S Whelan, JT Whitcomb, SE Whiting, BF Wiley, S Wilkinson, C Willems, PA Williams, PR Williams, R Willke, B Wilson, A Winjum, BJ Winkler, W Wise, S Wiseman, AG Woan, G Woods, D Wooley, R Worden, J Wu, W Yakushin, I Yamamoto, H Yoshida, S Zaleski, KD Zanolin, M Zawischa, I Zhang, L Zhu, R Zotov, N Zucker, M Zweizig, J CA LIGO Sci Collaboration TI Search for gravitational waves from primordial black hole binary coalescences in the galactic halo SO PHYSICAL REVIEW D LA English DT Article ID INFLATIONARY COSMOLOGY; MACHO PROJECT AB We use data from the second science run of the LIGO gravitational-wave detectors to search for the gravitational waves from primordial black hole binary coalescence with component masses in the range 0.2-1.0M. The analysis requires a signal to be found in the data from both LIGO observatories, according to a set of coincidence criteria. No inspiral signals were found. Assuming a spherical halo with core radius 5 kpc extending to 50 kpc containing nonspinning black holes with masses in the range 0.2-1.0M, we place an observational upper limit on the rate of primordial black hole coalescence of 63 per year per Milky Way halo (MWH) with 90% confidence. C1 CALTECH, LIGO, Pasadena, CA 91125 USA. Max Planck Inst Gravitat Phys, Albert Einstein Inst, D-14476 Golm, Germany. Max Planck Inst Gravitat Phys, Albert Einstein Inst, D-30167 Hannover, Germany. Australian Natl Univ, Canberra, ACT 0200, Australia. Calif State Univ Dominguez Hills, Carson, CA 90747 USA. CALTECH, CaRT, Pasadena, CA 91125 USA. Univ Cardiff Wales, Cardiff CF2 3YB, Wales. Carleton Coll, Northfield, MN 55057 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Hobart & William Smith Coll, Geneva, NY 14456 USA. Inter Univ Ctr Astron & Astrophys, Pune 411007, Maharashtra, India. MIT, LIGO, Cambridge, MA 02139 USA. LIFO Hanford Observ, Richland, WA 99352 USA. LIFO Livingston Observ, Livingston, LA 70754 USA. Louisiana State Univ, Baton Rouge, LA 70803 USA. Louisiana Tech Univ, Ruston, LA 71272 USA. Loyola Univ, New Orleans, LA 70118 USA. Max Planck Inst Quantum Opt, D-85748 Garching, Germany. Moscow MV Lomonosov State Univ, Moscow 119992, Russia. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Natl Astron Observ Japan, Tokyo 1818588, Japan. Northwestern Univ, Evanston, IL 60208 USA. Salish Kootenai Coll, Pablo, MT 59855 USA. SE Louisiana Univ, Hammond, LA 70402 USA. Stanford Univ, Stanford, CA 94305 USA. Syracuse Univ, Syracuse, NY 13244 USA. Penn State Univ, University Pk, PA 16802 USA. Univ Texas Brownsville, Brownsville, TX 78520 USA. Texas Southmost Coll, Brownsville, TX 78520 USA. Trinity Univ, Austin, TX 78712 USA. Univ Hannover, D-30167 Hannover, Germany. Univ Illes Balears, E-07122 Palma de Mallorca, Spain. Univ Birmingham, Birmingham B15 2TT, W Midlands, England. Univ Florida, Gainesville, FL 32611 USA. Univ Glasgow, Glasgow G12 8QQ, Lanark, Scotland. Univ Michigan, Ann Arbor, MI 48109 USA. Univ Oregon, Eugene, OR 97403 USA. Univ Rochester, Rochester, NY 14627 USA. Univ Wisconsin, Milwaukee, WI 53201 USA. Washington State Univ, Pullman, WA 99164 USA. HP Labs, Palo Alto, CA USA. CNRS, Inst Astrophys Paris, GReCO, F-75700 Paris, France. Columbia Univ, New York, NY 10027 USA. Univ Tokyo, Inst Cosm Ray Res, Tokyo, Japan. Univ Coll Dublin, Dublin, Ireland. IBM Canada Ltd, Markham, ON, Canada. CALTECH, Jet Prop Lab, Pasadena, CA USA. RP Abbott, B (reprint author), CALTECH, LIGO, Pasadena, CA 91125 USA. RI Sylvestre, Julien/A-8610-2009; Beausoleil, Raymond/C-5076-2009; McClelland, David/E-6765-2010; Hild, Stefan/A-3864-2010; 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; Freise, Andreas/F-8892-2011; Finn, Lee Samuel/A-3452-2009; 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; Pitkin, Matthew/I-3802-2013; Liu, Sheng/K-2815-2013; Vyatchanin, Sergey/J-2238-2012; van Putten, Maurice/F-5237-2011; Vecchio, Alberto/F-8310-2015; Ottaway, David/J-5908-2015; Ottewill, Adrian/A-1838-2016; Messaritaki, Eirini/D-7393-2016; Sigg, Daniel/I-4308-2015; Harms, Jan/J-4359-2012; Frey, Raymond/E-2830-2016 OI Sylvestre, Julien/0000-0001-8136-4348; McClelland, David/0000-0001-6210-5842; Strain, Kenneth/0000-0002-2066-5355; Lueck, Harald/0000-0001-9350-4846; Finn, Lee Samuel/0000-0002-3937-0688; Allen, Bruce/0000-0003-4285-6256; Pitkin, Matthew/0000-0003-4548-526X; Vecchio, Alberto/0000-0002-6254-1617; Ottewill, Adrian/0000-0003-3293-8450; Sigg, Daniel/0000-0003-4606-6526; Frey, Raymond/0000-0003-0341-2636 NR 28 TC 10 Z9 10 U1 1 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1550-7998 J9 PHYS REV D JI Phys. Rev. D PD OCT PY 2005 VL 72 IS 8 AR 082002 DI 10.1103/PhysRevD.72.082002 PG 8 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 979IX UT WOS:000232936700003 ER PT J AU Abbott, B Abbott, R Adhikari, R Ageev, A Allen, B Amin, R Anderson, SB Anderson, WG Araya, M Armandula, H Ashley, M Asiri, F Aufmuth, P Aulbert, C Babak, S Balasubramanian, R Ballmer, S Barish, BC Barker, C Barker, D Barnes, M Barr, B Barton, MA Bayer, K Beausoleil, R Belczynski, K Bennett, R Berukoff, SJ Betzwieser, J Bhawal, B Bilenko, IA Billingsley, G Black, E Blackburn, K Blackburn, L Bland, B Bochner, B Bogue, L Bork, R Bose, S Brady, PR Braginsky, VB Brau, JE Brown, DA Bullington, A Bunkowski, A Buonanno, A Burgess, R Busby, D Butler, WE Byer, RL Cadonati, L Cagnoli, G Camp, JB Cantley, CA Cardenas, L Carter, K Casey, MM Castiglione, J Chandler, A Chapsky, J Charlton, P Chatterji, S Chelkowski, S Chen, Y Chickarmane, V Chin, D Christensen, N Churches, D Cokelaer, T Colacino, C Coldwell, R Coles, M Cook, D Corbitt, T Coyne, D Creighton, JDE Creighton, TD Crooks, DRM Csatorday, P Cusack, BJ Cutler, C D'Ambrosio, E Danzmann, K Daw, E DeBra, D Delker, T Dergachev, V DeSalvo, R Dhurandhar, S Di Credico, A Diaz, M Ding, H Drever, RWP Dupuis, RJ Edlund, JA Ehrens, P Elliffe, EJ Etzel, T Evans, M Evans, T Fairhurst, S Fallnich, C Farnham, D Fejer, MM Findley, T Fine, M Finn, LS Franzen, KY Freise, A Frey, R Fritschel, P Frolov, VV Fyffe, M Ganezer, KS Garofoli, J Giaime, JA Gillespie, A Goda, K Gonzalez, G Gossler, S Grandclement, P Grant, A Gray, C Gretarsson, AM Grimmett, D Grote, H Grunewald, S Guenther, M Gustafson, E Gustafson, R Hamilton, WO Hammond, M Hanson, J Hardham, C Harms, J Harry, G Hartunian, A Heefner, J Hefetz, Y Heinzel, G Heng, IS Hennessy, M Hepler, N Heptonstall, A Heurs, M Hewitson, M Hild, S Hindman, N Hoang, P Hough, J Hrynevych, M Hua, W Ito, M Itoh, Y Ivanov, A Jennrich, O Johnson, B Johnson, WW Johnston, WR Jones, DI Jones, L Jungwirth, D Kalogera, V Katsavounidis, E Kawabe, K Kawamura, S Kells, W Kern, J Khan, A Killbourn, S Killow, CJ Kim, C King, C King, P Klimenko, S Koranda, S Kotter, K Kovalik, J Kozak, D Krishnan, B Landry, M Langdale, J Lantz, B Lawrence, R Lazzarini, A Lei, M Leonor, I Libbrecht, K Libson, A Lindquist, P Liu, S Logan, J Lormand, M Lubinski, M Luck, H Lyons, TT Machenschalk, B MacInnis, M Mageswaran, M Mailand, K Majid, W Malec, M Mann, F Marin, A Marka, S Maros, E Mason, J Mason, K Matherny, O Matone, L Mavalvala, N McCarthy, R McClelland, DE McHugh, M McNabb, JWC Mendell, G Mercer, RA Meshkov, S Messaritaki, E Messenger, C Mitrofanov, VP Mitselmakher, G Mittleman, R Miyakawa, O Miyoki, S Mohanty, S Moreno, G Mossavi, K Mueller, G Mukherjee, S Murray, P Myers, J Nagano, S Nash, T Nayak, R Newton, G Nocera, F Noel, JS Nutzman, P Olson, T O'Reilly, B Ottaway, DJ Ottewill, A Ouimette, D Overmier, H Owen, BJ Pan, Y Papa, MA Parameshwaraiah, V Parameswaran, A Parameswariah, C Pedraza, M Penn, S Pitkin, M Plissi, M Prix, R Quetschke, V Raab, F Radkins, H Rahkola, R Rakhmanov, M Rao, SR Rawlins, K Ray-Majumder, S Re, V Redding, D Regehr, MW Regimbau, T Reid, S Reilly, KT Reithmaier, K Reitze, DH Richman, S Riesen, R Riles, K Rivera, B Rizzi, A Robertson, DI Robertson, NA Robison, L Roddy, S Rollins, J Romano, JD Romie, J Rong, H Rose, D Rotthoff, E Rowan, S Rudiger, A Russell, P Ryan, K Salzman, I Sandberg, V Sanders, GH Sannibale, V Sathyaprakash, B Saulson, PR Savage, R Sazonov, A Schilling, R Schlaufman, K Schmidt, V Schnabel, R Schofield, R Schutz, BF Schwinberg, P Scott, SM Seader, SE Searle, AC Sears, B Seel, S Seifert, F Sengupta, AS Shapiro, CA Shawhan, P Shoemaker, DH Shu, QZ Sibley, A Siemens, X Sievers, L Sigg, D Sintes, AM Smith, JR Smith, M Smith, MR Sneddon, PH Spero, R Stapfer, G Steussy, D Strain, KA Strom, D Stuver, A Summerscales, T Sumner, MC Sutton, PJ Sylvestre, J Takamori, A Tanner, DB Tariq, H Taylor, I Taylor, R Taylor, R Thorne, KA Thorne, KS Tibbits, M Tilav, S Tinto, M Tokmakov, KV Torres, C Torrie, C Traylor, G Tyler, W Ugolini, D Ungarelli, C Vallisneri, M van Putten, M Vass, S Vecchio, A Veitch, J Vorvick, C Vyachanin, SP Wallace, L Walther, H Ward, H Ware, B Watts, K Webber, D Weidner, A Weiland, U Weinstein, A Weiss, R Welling, H Wen, L Wen, S Whelan, JT Whitcomb, SE Whiting, BF Wiley, S Wilkinson, C Willems, PA Williams, PR Williams, R Willke, B Wilson, A Winjum, BJ Winkler, W Wise, S Wiseman, AG Woan, G Woods, D Wooley, R Worden, J Wu, W Yakushin, I Yamamoto, H Yoshida, S Zaleski, KD Zanolin, M Zawischa, I Zhang, L Zhu, R Zotov, N Zucker, M Zweizig, J AF Abbott, B Abbott, R Adhikari, R Ageev, A Allen, B Amin, R Anderson, SB Anderson, WG Araya, M Armandula, H Ashley, M Asiri, F Aufmuth, P Aulbert, C Babak, S Balasubramanian, R Ballmer, S Barish, BC Barker, C Barker, D Barnes, M Barr, B Barton, MA Bayer, K Beausoleil, R Belczynski, K Bennett, R Berukoff, SJ Betzwieser, J Bhawal, B Bilenko, IA Billingsley, G Black, E Blackburn, K Blackburn, L Bland, B Bochner, B Bogue, L Bork, R Bose, S Brady, PR Braginsky, VB Brau, JE Brown, DA Bullington, A Bunkowski, A Buonanno, A Burgess, R Busby, D Butler, WE Byer, RL Cadonati, L Cagnoli, G Camp, JB Cantley, CA Cardenas, L Carter, K Casey, MM Castiglione, J Chandler, A Chapsky, J Charlton, P Chatterji, S Chelkowski, S Chen, Y Chickarmane, V Chin, D Christensen, N Churches, D Cokelaer, T Colacino, C Coldwell, R Coles, M Cook, D Corbitt, T Coyne, D Creighton, JDE Creighton, TD Crooks, DRM Csatorday, P Cusack, BJ Cutler, C D'Ambrosio, E Danzmann, K Daw, E DeBra, D Delker, T Dergachev, V DeSalvo, R Dhurandhar, S Di Credico, A Diaz, M Ding, H Drever, RWP Dupuis, RJ Edlund, JA Ehrens, P Elliffe, EJ Etzel, T Evans, M Evans, T Fairhurst, S Fallnich, C Farnham, D Fejer, MM Findley, T Fine, M Finn, LS Franzen, KY Freise, A Frey, R Fritschel, P Frolov, VV Fyffe, M Ganezer, KS Garofoli, J Giaime, JA Gillespie, A Goda, K Gonzalez, G Gossler, S Grandclement, P Grant, A Gray, C Gretarsson, AM Grimmett, D Grote, H Grunewald, S Guenther, M Gustafson, E Gustafson, R Hamilton, WO Hammond, M Hanson, J Hardham, C Harms, J Harry, G Hartunian, A Heefner, J Hefetz, Y Heinzel, G Heng, IS Hennessy, M Hepler, N Heptonstall, A Heurs, M Hewitson, M Hild, S Hindman, N Hoang, P Hough, J Hrynevych, M Hua, W Ito, M Itoh, Y Ivanov, A Jennrich, O Johnson, B Johnson, WW Johnston, WR Jones, DI Jones, L Jungwirth, D Kalogera, V Katsavounidis, E Kawabe, K Kawamura, S Kells, W Kern, J Khan, A Killbourn, S Killow, CJ Kim, C King, C King, P Klimenko, S Koranda, S Kotter, K Kovalik, J Kozak, D Krishnan, B Landry, M Langdale, J Lantz, B Lawrence, R Lazzarini, A Lei, M Leonor, I Libbrecht, K Libson, A Lindquist, P Liu, S Logan, J Lormand, M Lubinski, M Luck, H Lyons, TT Machenschalk, B MacInnis, M Mageswaran, M Mailand, K Majid, W Malec, M Mann, F Marin, A Marka, S Maros, E Mason, J Mason, K Matherny, O Matone, L Mavalvala, N McCarthy, R McClelland, DE McHugh, M McNabb, JWC Mendell, G Mercer, RA Meshkov, S Messaritaki, E Messenger, C Mitrofanov, VP Mitselmakher, G Mittleman, R Miyakawa, O Miyoki, S Mohanty, S Moreno, G Mossavi, K Mueller, G Mukherjee, S Murray, P Myers, J Nagano, S Nash, T Nayak, R Newton, G Nocera, F Noel, JS Nutzman, P Olson, T O'Reilly, B Ottaway, DJ Ottewill, A Ouimette, D Overmier, H Owen, BJ Pan, Y Papa, MA Parameshwaraiah, V Parameswaran, A Parameswariah, C Pedraza, M Penn, S Pitkin, M Plissi, M Prix, R Quetschke, V Raab, F Radkins, H Rahkola, R Rakhmanov, M Rao, SR Rawlins, K Ray-Majumder, S Re, V Redding, D Regehr, MW Regimbau, T Reid, S Reilly, KT Reithmaier, K Reitze, DH Richman, S Riesen, R Riles, K Rivera, B Rizzi, A Robertson, DI Robertson, NA Robison, L Roddy, S Rollins, J Romano, JD Romie, J Rong, H Rose, D Rotthoff, E Rowan, S Rudiger, A Russell, P Ryan, K Salzman, I Sandberg, V Sanders, GH Sannibale, V Sathyaprakash, B Saulson, PR Savage, R Sazonov, A Schilling, R Schlaufman, K Schmidt, V Schnabel, R Schofield, R Schutz, BF Schwinberg, P Scott, SM Seader, SE Searle, AC Sears, B Seel, S Seifert, F Sengupta, AS Shapiro, CA Shawhan, P Shoemaker, DH Shu, QZ Sibley, A Siemens, X Sievers, L Sigg, D Sintes, AM Smith, JR Smith, M Smith, MR Sneddon, PH Spero, R Stapfer, G Steussy, D Strain, KA Strom, D Stuver, A Summerscales, T Sumner, MC Sutton, PJ Sylvestre, J Takamori, A Tanner, DB Tariq, H Taylor, I Taylor, R Taylor, R Thorne, KA Thorne, KS Tibbits, M Tilav, S Tinto, M Tokmakov, KV Torres, C Torrie, C Traylor, G Tyler, W Ugolini, D Ungarelli, C Vallisneri, M van Putten, M Vass, S Vecchio, A Veitch, J Vorvick, C Vyachanin, SP Wallace, L Walther, H Ward, H Ware, B Watts, K Webber, D Weidner, A Weiland, U Weinstein, A Weiss, R Welling, H Wen, L Wen, S Whelan, JT Whitcomb, SE Whiting, BF Wiley, S Wilkinson, C Willems, PA Williams, PR Williams, R Willke, B Wilson, A Winjum, BJ Winkler, W Wise, S Wiseman, AG Woan, G Woods, D Wooley, R Worden, J Wu, W Yakushin, I Yamamoto, H Yoshida, S Zaleski, KD Zanolin, M Zawischa, I Zhang, L Zhu, R Zotov, N Zucker, M Zweizig, J CA LIGO Sci Collaboration TI Search for gravitational waves from galactic and extra-galactic binary neutron stars SO PHYSICAL REVIEW D LA English DT Article ID INSPIRALING COMPACT BINARIES; LIGO; TEMPLATES; EVENTS; RATES; DETECTORS; SYSTEMS; PULSARS; FORMS AB We use 373 hours (approximate to 15 days) of data from the second science run of the LIGO gravitational-wave detectors to search for signals from binary neutron star coalescences within a maximum distance of about 1.5 Mpc, a volume of space which includes the Andromeda Galaxy and other galaxies of the Local Group of galaxies. This analysis requires a signal to be found in data from detectors at the two LIGO sites, according to a set of coincidence criteria. The background (accidental coincidence rate) is determined from the data and is used to judge the significance of event candidates. No inspiral gravitational-wave events were identified in our search. Using a population model which includes the Local Group, we establish an upper limit of less than 47 inspiral events per year per Milky Way equivalent galaxy with 90% confidence for nonspinning binary neutron star systems with component masses between 1 and 3M. C1 CALTECH, LIGO, Pasadena, CA 91125 USA. Max Planck Inst Gravitat Phys, Albert Einstein Inst, D-14476 Golm, Germany. Max Planck Inst Gravitat Phys, Albert Einstein Inst, D-30167 Hannover, Germany. Australian Natl Univ, Canberra, ACT 0200, Australia. Calif State Univ Dominguez Hills, Carson, CA 90747 USA. CALTECH, CaRT, Pasadena, CA 91125 USA. Cardiff Univ, Cardiff CF2 3YB, Wales. Carleton Coll, Northfield, MN 55057 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Hobart & William Smith Coll, Geneva, NY 14456 USA. Inter Univ Ctr Astron & Astrophys, Pune 411007, Maharashtra, India. MIT, LIGO, Cambridge, MA 02139 USA. LIGO Hanford Observ, Richland, WA 99352 USA. LIGO Livingston Observ, Livingston, LA USA. Louisiana State Univ, Baton Rouge, LA 70803 USA. Louisiana Tech Univ, Ruston, LA 71272 USA. Loyola Univ, New Orleans, LA 70118 USA. Max Planck Inst Quantum Opt, D-85748 Garching, Germany. Moscow MV Lomonosov State Univ, Moscow 119992, Russia. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Natl Astron Observ Japan, Tokyo 1818588, Japan. Northwestern Univ, Evanston, IL 60208 USA. Salish Kootenai Coll, Pablo, MT 59855 USA. SE Louisiana Univ, Hammond, LA 70402 USA. Stanford Univ, Stanford, CA 94305 USA. Syracuse Univ, Syracuse, NY 13244 USA. Penn State Univ, University Pk, PA 16802 USA. Univ Texas Brownsville, Brownsville, TX 78520 USA. Texas Southmost Coll, Brownsville, TX 78520 USA. Trinity Univ, San Antonio, TX 78212 USA. Leibniz Univ Hannover, D-30167 Hannover, Germany. Univ Illes Balears, E-07122 Palma de Mallorca, Spain. Univ Birmingham, Birmingham B15 2TT, W Midlands, England. Univ Florida, Gainesville, FL 32611 USA. Univ Glasgow, Glasgow G12 8QQ, Lanark, Scotland. Univ Michigan, Ann Arbor, MI 48109 USA. Univ Oregon, Eugene, OR 97403 USA. Univ Rochester, Rochester, NY 14627 USA. Univ Wisconsin, Milwaukee, WI 53201 USA. Washington State Univ, Pullman, WA 99164 USA. HP Labs, Palo Alto, CA USA. CNRS, Inst Astrophys Paris, GReCO, F-75700 Paris, France. Columbia Univ, New York, NY 10027 USA. Univ Tokyo, Inst Cosm Ray Res, Tokyo, Japan. Univ Coll Dublin, Dublin, Ireland. IBM Canada Ltd, Markham, ON, Canada. CALTECH, Jet Prop Lab, Pasadena, CA USA. RP Abbott, B (reprint author), CALTECH, LIGO, Pasadena, CA 91125 USA. RI Harms, Jan/J-4359-2012; Frey, Raymond/E-2830-2016; Pitkin, Matthew/I-3802-2013; Vyatchanin, Sergey/J-2238-2012; Chen, Yanbei/A-2604-2013; Barker, David/A-5671-2013; Liu, Sheng/K-2815-2013; Hild, Stefan/A-3864-2010; Vecchio, Alberto/F-8310-2015; Agresti, Juri/G-8168-2012; Ottaway, David/J-5908-2015; Ottewill, Adrian/A-1838-2016; Messaritaki, Eirini/D-7393-2016; Sigg, Daniel/I-4308-2015; Casey, Morag/C-9703-2010; Raab, Frederick/E-2222-2011; Rowan, Sheila/E-3032-2010; Beausoleil, Raymond/C-5076-2009; McClelland, David/E-6765-2010; Kawabe, Keita/G-9840-2011; Lueck, Harald/F-7100-2011; Strain, Kenneth/D-5236-2011; Bilenko, Igor/D-5172-2012; Freise, Andreas/F-8892-2011; Mitrofanov, Valery/D-8501-2012; Allen, Bruce/K-2327-2012; van Putten, Maurice/F-5237-2011; Schutz, Bernard/B-1504-2010; Sylvestre, Julien/A-8610-2009; Finn, Lee Samuel/A-3452-2009; OI Frey, Raymond/0000-0003-0341-2636; Fairhurst, Stephen/0000-0001-8480-1961; Taylor, Ian/0000-0001-5040-0772; Zweizig, John/0000-0002-1521-3397; Aulbert, Carsten/0000-0002-1481-8319; Tanner, David/0000-0003-1940-4710; Heurs, Michele/0000-0002-5577-2273; Messaritaki, Eirini/0000-0002-9917-4160; Pitkin, Matthew/0000-0003-4548-526X; Vecchio, Alberto/0000-0002-6254-1617; Agresti, Juri/0000-0001-6119-2470; Ottewill, Adrian/0000-0003-3293-8450; Sigg, Daniel/0000-0003-4606-6526; McClelland, David/0000-0001-6210-5842; Lueck, Harald/0000-0001-9350-4846; Strain, Kenneth/0000-0002-2066-5355; Allen, Bruce/0000-0003-4285-6256; Sylvestre, Julien/0000-0001-8136-4348; Finn, Lee Samuel/0000-0002-3937-0688; Freise, Andreas/0000-0001-6586-9901; Mitra, Sanjit/0000-0002-0800-4626; Tokmakov, Kirill/0000-0002-2808-6593; Whiting, Bernard F/0000-0002-8501-8669; Veitch, John/0000-0002-6508-0713; Papa, M.Alessandra/0000-0002-1007-5298 NR 39 TC 105 Z9 105 U1 2 U2 11 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1550-7998 EI 1550-2368 J9 PHYS REV D JI Phys. Rev. D PD OCT PY 2005 VL 72 IS 8 AR 082001 DI 10.1103/PhysRevD.72.082001 PG 22 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 979IX UT WOS:000232936700002 ER PT J AU Buonanno, A Chen, YB Pan, Y Tagoshi, H Vallisneri, M AF Buonanno, A Chen, YB Pan, Y Tagoshi, H Vallisneri, M TI Detecting gravitational waves from precessing binaries of spinning compact objects. II. Search implementation for low-mass binaries SO PHYSICAL REVIEW D LA English DT Article ID POST-NEWTONIAN ORDER; COALESCING BINARIES; INSPIRALING BINARIES; SYSTEMS; RADIATION; TEMPLATES; FILTERS; CHOICE; FORMS AB Detection template families (DTFs) are built to capture the essential features of true gravitational waveforms using a small set of phenomenological waveform parameters. Buonanno, Chen, and Vallisneri [Phys. Rev. D 67, 104025 (2003)] proposed the BCV2 DTF to perform computationally efficient searches for signals from precessing binaries of compact stellar objects. Here we test the signal-matching performance of the BCV2 DTF for asymmetric-mass-ratio binaries, and specifically for double-black-hole binaries with component masses (m(1),m(2))is an element of[6,12]Mx[1,3]M, and for black-hole-neutron-star binaries with component masses (m(1),m(2))=(10M,1.4M); we take all black holes to be maximally spinning. We find a satisfactory signal-matching performance, with fitting factors averaging between 0.94 and 0.98. We also scope out the region of BCV2 parameters needed for a template-based search, we evaluate the template match metric, we discuss a template-placement strategy, and we estimate the number of templates needed for searches at the LIGO design sensitivity. In addition, after gaining more insight in the dynamics of spin-orbit precession, we propose a modification of the BCV2 DTF that is parametrized by physical (rather than phenomenological) parameters. We test this modified "BCV2P" DTF for the (10M, 1.4M) black-hole-neutron-star system, finding a signal-matching performance comparable to the BCV2 DTF, and a reliable parameter-estimation capability for target-binary quantities such as the chirp mass and the opening angle (the angle between the black-hole spin and the orbital angular momentum). C1 Univ Paris 07, Observ Paris, CEA, Lab Astroparticule & Cosmol,CNRS,UMR 7164, F-75005 Paris, France. Max Planck Inst Gravitat Phys, Albert Einstein Inst, D-14476 Golm, Germany. CALTECH, Pasadena, CA 91125 USA. Osaka Univ, Grad Sch Sci, Dept Earth & Space Sci, Toyonaka, Osaka 5600043, Japan. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Buonanno, A (reprint author), Inst Astrophys Paris, 98bis Blvd Arago, F-75013 Paris, France. RI Chen, Yanbei/A-2604-2013 NR 26 TC 31 Z9 31 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1550-7998 EI 1550-2368 J9 PHYS REV D JI Phys. Rev. D PD OCT PY 2005 VL 72 IS 8 AR 084027 DI 10.1103/PhysRevD.72.084027 PG 18 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 979IX UT WOS:000232936700057 ER PT J AU Dodelson, S Zhang, PJ AF Dodelson, S Zhang, PJ TI Weak lensing bispectrum SO PHYSICAL REVIEW D LA English DT Article ID COSMOLOGICAL PARAMETERS; POWER SPECTRUM; DARK-MATTER; GALAXIES; SKEWNESS; PROBE AB Weak gravitational lensing of background galaxies offers an excellent opportunity to study the intervening distribution of matter. While much attention to date has focused on the two-point-function of the cosmic shear, the three-point-function, the bispectrum, also contains very useful cosmological information. Here, we compute three corrections to the bispectrum which are nominally of the same order as the leading term. We show that the corrections are small, so they can be ignored when analyzing present surveys. However, they will eventually have to be included for accurate parameter estimates from future surveys. C1 NASA, Fermilab Astrophys Ctr, Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Chicago, Ctr Astron & Astrophys, Chicago, IL 60637 USA. Northwestern Univ, Dept Phys & Astron, Evanston, IL 60208 USA. RP Dodelson, S (reprint author), NASA, Fermilab Astrophys Ctr, Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RI ZHANG, PENGJIE/O-2825-2015 NR 30 TC 28 Z9 28 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1550-7998 EI 1550-2368 J9 PHYS REV D JI Phys. Rev. D PD OCT PY 2005 VL 72 IS 8 AR 083001 DI 10.1103/PhysRevD.72.083001 PG 9 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 979IX UT WOS:000232936700004 ER PT J AU Shariff, K Wang, M AF Shariff, K Wang, M TI A numerical experiment to determine whether surface shear-stress fluctuations are a true sound source SO PHYSICS OF FLUIDS LA English DT Article ID TURBULENT-BOUNDARY-LAYER; STREAMWISE WAVE-NUMBERS; WALL; PRESSURE; FLOW; MACH; RADIATION; NOISE; GENERATION AB The sound generated due to a localized flow over a large (compared to the acoustic wavelength) plane no-slip wall is considered. It has been known since 1960 that for inviscid flow the pressure, while appearing to be a source of dipole sound in a formal solution to the Lighthill equation, is, in fact, not a true dipole source, but rather represents the surface reflection of volume quadrupoles. The subject of the present work-namely, whether a similar surface shear stress term constitutes a true source of dipole sound-has been controversial. Some have boldly assumed it to be a true source and have used it to calculate the noise in boundary-layer flows. Others have argued that, like the surface pressure, the surface shear stress is not a valid source of sound but rather represents a propagation effect. Here, a numerical experiment is undertaken to investigate the issue. A portion of an otherwise static wall is oscillated tangentially in an acoustically compact region to create shear stress fluctuations. The resulting sound field, computed directly from the compressible Navier-Stokes equations, is nearly dipolar and its amplitude agrees with an acoustic analogy prediction that regards the surface shear as acoustically compact and as a true source of sound. However, there is a correction that becomes noticeable for observers near wall-grazing angles as the computational domain size L-d along the wall is increased. An estimate, validated by the simulations, shows that as L-d->infinity the correction to the sound in the Fraunhofer zone is proportional to delta(bl)/lambda (the ratio of oscillatory boundary-layer thickness to acoustic wavelength) times a directivity factor that becomes large at angles close to grazing. For observers at such angles, Lighthill's acoustic analogy does not apply. (c) 2005 American Institute of Physics. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. NASA, Stanford Ctr Turbulence Res, Stanford, CA 94305 USA. RP Shariff, K (reprint author), NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RI Wang, Meng/C-1622-2012; OI Shariff, Karim/0000-0002-7256-2497 NR 27 TC 10 Z9 12 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 1070-6631 J9 PHYS FLUIDS JI Phys. Fluids PD OCT PY 2005 VL 17 IS 10 AR 107105 DI 10.1063/1.2112747 PG 11 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 979JW UT WOS:000232939200064 ER PT J AU Hesse, M Kuznetsova, M Schindler, K Birn, J AF Hesse, M Kuznetsova, M Schindler, K Birn, J TI Three-dimensional modeling of electron quasiviscous dissipation in guide-field magnetic reconnection SO PHYSICS OF PLASMAS LA English DT Article ID THIN CURRENT SHEETS; SIMULATIONS; INSTABILITY; CHALLENGE AB A numerical study of guide-field magnetic reconnection in a three-dimensional model is presented. Starting from an initial, perturbed, force-free current sheet, it is shown that reconnection develops to an almost translationally invariant state, where magnetic perturbations are aligned primarily along the main current flow direction. An analysis of guide-field and electron flow signatures indicates behavior that is very similar to earlier, albeit not three-dimensional, simulations. Furthermore, a detailed investigation of electron pressure nongyrotropies in the central diffusion region confirms the major role the associated dissipation process plays in establishing the reconnection electric field. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Ruhr Univ Bochum, D-44780 Bochum, Germany. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Hesse, M (reprint author), NASA, Goddard Space Flight Ctr, Code 661, Greenbelt, MD 20771 USA. RI Hesse, Michael/D-2031-2012; Kuznetsova, Maria/F-6840-2012; NASA MMS, Science Team/J-5393-2013 OI NASA MMS, Science Team/0000-0002-9504-5214 NR 19 TC 13 Z9 13 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD OCT PY 2005 VL 12 IS 10 AR 100704 DI 10.1063/1.2114350 PG 4 WC Physics, Fluids & Plasmas SC Physics GA 978EG UT WOS:000232855800004 ER PT J AU Smith, HD McKay, CP AF Smith, HD McKay, CP TI Drilling in ancient permafrost on Mars for evidence of a second genesis of life SO PLANETARY AND SPACE SCIENCE LA English DT Article DE Mars; exobiology; ice; search for life; experimental techniques ID GLOBAL DISTRIBUTION; GROUND ICE; PRESERVATION; SEDIMENTS; DEPOSITS; SEARCH; EARTH AB If life ever existed on Mars, a key question is the genetic relationship of that life to life on Earth. To determine if Martian life represents a separate, second genesis of life requires the analysis of organisms, not fossils. Ancient permafrost on Mars represents one potential source of intact, albeit probably dead by radiation, Martian organisms. Strong crustal magnetism in the ancient heavily cratered southern highlands between 60 and 80 degrees S and at about 180 degrees W indicates what may be the oldest, best preserved ice-rich permafrost on Mars. Drilling to depths of 1000 m would reach samples unaffected by possible warming due to cyclic changes in Mars' obliquity. When drilling into the permafrost to retrieve ancient intact Martian organisms, it is necessary to take special precautions to avoid the possibility of contamination. Earth permafrost provides an analog for Martian permafrost and convenient sites for instrument development and field testing. (c) 2005 Elsevier Ltd. All rights reserved. C1 NASA, Ames Res Ctr, Space Sci Div, Moffett Field, CA 94035 USA. NASA Ames, SETI Inst, Moffett Field, CA 94035 USA. Int Space Univ, Strasbourg, France. RP Smith, HD (reprint author), NASA, Ames Res Ctr, Space Sci Div, Mail Stop 245-3,Moffett Field, Moffett Field, CA 94035 USA. EM hdsmith@mail.arc.nasa.gov NR 36 TC 23 Z9 25 U1 4 U2 7 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 OCT PY 2005 VL 53 IS 12 BP 1302 EP 1308 DI 10.1016/j.pss.2005.07.006 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 969NG UT WOS:000232240300009 ER PT J AU Drake, GW Hawkins, TW Hall, LA Boatz, JA Brand, AJ AF Drake, GW Hawkins, TW Hall, LA Boatz, JA Brand, AJ TI Structural and theoretical investigations of 3,4,5-triamino-1,2,4-triazolium salts SO PROPELLANTS EXPLOSIVES PYROTECHNICS LA English DT Article DE heterocycles; nitrate; perchlorate; dinitramide; calculations ID MOLECULAR-ORBITAL METHODS; ALKALI-METAL NITRATES; N-15 NMR-SPECTROSCOPY; IONIC LIQUIDS; X-RAY; POLYFLUOROALKYL-1,2,4-TRIAZOLIUM SALTS; THERMAL-DECOMPOSITION; ENERGETIC MATERIALS; HYDRAZINIUM SALTS; DINITRAMIDE ANION AB Reactions using the high nitrogen heterocycle 3,4,5-trianiino-1,2.4-triazole (guanazine) with strong acids (HNO(3), HClO(4), and "HN(NO(2))(2)") resulted in a family of highly stable salts. All of the salts were characterized using spectroscopic as well as single crystal X-ray diffraction studies. The X-ray structures were compared to that obtained from theoretical calculations (MP2/6-311 + G(d, p) level). Initial safety testing (impact, friction) was carried out on all of the new materials. C1 George C Marshall Space Flight Ctr, Propuls Res Lab, Huntsville, AL 35812 USA. AFRL PRSP, Space & Missile Propuls Div, Edwards AFB, CA 93524 USA. RP Drake, GW (reprint author), George C Marshall Space Flight Ctr, Propuls Res Lab, XD22, Huntsville, AL 35812 USA. EM Gregory.W.Drake@nasa.gov NR 88 TC 34 Z9 34 U1 0 U2 7 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0721-3115 J9 PROPELL EXPLOS PYROT JI Propellants Explos. Pyrotech. PD OCT PY 2005 VL 30 IS 5 BP 329 EP 337 DI 10.1002/prep.200500022 PG 9 WC Chemistry, Applied; Engineering, Chemical SC Chemistry; Engineering GA 982FM UT WOS:000233143400003 ER PT J AU Sirianni, M Jee, MJ Benitez, N Blakeslee, JP Martel, AR Meurer, G Clampin, M De Marchi, G Ford, HC Gilliland, R Hartig, GF Illingworth, GD Mack, J McCann, WJ AF Sirianni, M Jee, MJ Benitez, N Blakeslee, JP Martel, AR Meurer, G Clampin, M De Marchi, G Ford, HC Gilliland, R Hartig, GF Illingworth, GD Mack, J McCann, WJ TI The photometric performance and calibration of the Hubble Space Telescope Advanced Camera for Surveys SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC LA English DT Review ID CHARGE-TRANSFER EFFICIENCY; HIGH-REDSHIFT GALAXIES; ON-ORBIT PERFORMANCE; CCD DETECTORS; SBF SURVEY; WFPC2; ULTRAVIOLET; COLORS; DISTANCES; STARS AB We present the photometric calibration of the Advanced Camera for Surveys (ACS). The ACS was installed in the Hubble Space Telescope (HST) in 2002 March. It comprises three cameras: the Wide Field Channel (WFC), optimized for deep near-IR survey imaging programs; the High Resolution Channel (HRC), a high-resolution imager that fully samples the HST point-spread function (PSF) in the visible; and the Solar Blind Channel (SBC), a far-UV imager. A significant amount of data has been collected to characterize the on-orbit performance of the three channels. We give here an overview of the performance and calibration of the two CCD cameras (WFC and HRC) and a description of the best techniques for reducing ACS CCD data. The overall performance is as expected from prelaunch testing of the camera. Surprises were a better-than-predicted sensitivity in the visible and near-IR for both the WFC and HRC and an unpredicted dip in the HRC UV response at similar to 3200 A. On-orbit observations of spectrophotometric standard stars have been used to revise the prelaunch estimate of the instrument response curves to best match predicted and observed count rates. Synthetic photometry has been used to determine zero points for all filters in three magnitude systems and to derive interstellar extinction values for the ACS photometric systems. Due to the CCD internal scattering of long-wavelength photons, the width of the PSF increases significantly in the near-IR, and the aperture correction for photometry with near-IR filters depends on the spectral energy distribution of the source. We provide a detailed recipe to correct for the latter effect. Transformations between the ACS photometric systems and the UBVRI and WFPC2 systems are presented. In general, two sets of transformations are available: one based on the observation of two star clusters; the other on synthetic photometry. We discuss the accuracy of these transformations and their sensitivity to details of the spectra being transformed. Initial signs of detector degradation due to the HST radiative environment are already visible. We discuss the impact on the data in terms of dark rate increase, charge transfer inefficiency, and "hot" pixel population. C1 Space Telescope Sci Inst, Baltimore, MD 21218 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Ist Astrofis Andalucia, Granada 18008, Spain. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Calif Santa Cruz, Univ Calif Observ, Lick Observ, Santa Cruz, CA 95064 USA. RP Sirianni, M (reprint author), Space Telescope Sci Inst, 3700 San Martin Dr, Baltimore, MD 21218 USA. RI Clampin, mark/D-2738-2012; OI Benitez, Narciso/0000-0002-0403-7455; Blakeslee, John/0000-0002-5213-3548 NR 113 TC 719 Z9 720 U1 9 U2 24 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6280 J9 PUBL ASTRON SOC PAC JI Publ. Astron. Soc. Pac. PD OCT PY 2005 VL 117 IS 836 BP 1049 EP 1112 DI 10.1086/444553 PG 64 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 968QC UT WOS:000232176100002 ER PT J AU Shi, XZ McNider, RT Singh, MP England, DE Friedman, MJ Lapenta, WM Norris, WB AF Shi, XZ McNider, RT Singh, MP England, DE Friedman, MJ Lapenta, WM Norris, WB TI On the behavior of the stable boundary layer and the role of initial conditions SO PURE AND APPLIED GEOPHYSICS LA English DT Article DE stable boundary layer; predictability; bifurcation analysis; dynamical system ID MODEL; LAND; IMPLEMENTATION; SCHEME; SOIL AB Previous studies of the stable atmospheric boundary layer using techniques of nonlinear dynamical systems (MCNIDER et al., 1995) have shown that the equations support multiple solutions in certain parameter spaces. When geostrophic speed is used as a bifurcation parameter, two stable equilibria are found-a warm solution corresponding to the high-wind regime where the surface layer of the atmosphere stays coupled to the outer layer, and a cold solution corresponding to the low-wind, decoupled case. Between the stable equilibria is an unstable region where multiple solutions exist. The bifurcation diagram is a classic S shape with the foldback region showing the multiple solutions. These studies were carried out using a simple two-layer model of the atmosphere with a fairly complete surface energy budget. This allowed the dynamical analysis to be carried out on a coupled set of four ordinary differential equations. The present paper extends this work by examining additional bifurcation parameters and, more importantly, analyzing a set of partial differential equations with full vertical dependence. Simple mathematical representations of classical problems in dynamical analysis often exhibit interesting behavior, such as multiple solutions, that is not retained in the behavior of more complete representations. In the present case the S-shaped bifurcation diagram remains with only slight variations from the two-layer model. For the parameter space in the foldback region, the evolution of the boundary layer may be dramatically affected by the initial conditions at sunset. An eigenvalue analysis carried out to determine whether the system might support pure limit-cycle behavior showed that purely complex eigenvalues are not found. Thus, any cyclic behavior is likely to be transient. C1 Alabama A&M Univ, Huntsville, AL 35810 USA. Univ Alabama, Huntsville, AL 35899 USA. Ansal Inst Technol, Gurgaon, India. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Shi, XZ (reprint author), Alabama A&M Univ, Huntsville, AL 35810 USA. NR 21 TC 11 Z9 11 U1 0 U2 1 PU BIRKHAUSER VERLAG AG PI BASEL PA VIADUKSTRASSE 40-44, PO BOX 133, CH-4010 BASEL, SWITZERLAND SN 0033-4553 J9 PURE APPL GEOPHYS JI Pure Appl. Geophys. PD OCT PY 2005 VL 162 IS 10 BP 1811 EP 1829 DI 10.1007/s00024-005-2694-7 PG 19 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 948LW UT WOS:000230718300006 ER PT J AU Wargan, K Stajner, I Pawson, S Rood, RB Tan, WW AF Wargan, K Stajner, I Pawson, S Rood, RB Tan, WW TI Assimilation of ozone data from the Michelson Interferometer for Passive Atmospheric Sounding SO QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY LA English DT Article DE global model; limb sounder; lower stratosphere ID GLOBAL CHEMISTRY; TRANSPORT MODEL; SATELLITE DATA; STRATOSPHERE; VALIDATION; SELECTION; PROFILES; SYSTEM AB Global ozone profiles from the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) were added to an assimilation system that includes ozone data from the Solar Backscatter Ultraviolet/2 (SBUV/2) instrument. Substantial impacts were found and investigated. MIPAS ozone profiles have a vertical resolution close to 3 km, retrieved from infrared limb emission radiances, with a height-dependent error of 4-8%; they were used over 12 layers, spanning between 60-80 hPa and 0.15-0.25 hPa. As a research instrument, MIPAS provides variable coverage from day to day, with occasional data gaps of several days. The operational SBUV/2 data give regular temporal coverage in sunlit areas, yielding total columns and partial profiles, assimilated for Umkehr layers 3 (126-63 hPa) to 12 (<0.25 hPa), with errors comparable to MIPAS near the ozone maximum but increasing substantially at higher and lower levels. The higher accuracy of MIPAS data leads to substantial improvements in the assimilated ozone below the ozone maximum when compared to accurate in situ (ozonesonde) and space-based (occultation) data; vertical gradients in the lower stratosphere are improved. In the Arctic winter of 2002/03, the ability of MIPAS to sample the vortex interior leads to substantial beneficial impacts. In the tropics, assimilation of MIPAS profiles improves analyses in the lower stratosphere and provides substantially better agreement with occultation data in the middle stratosphere, near the ozone maximum. This offsets an underestimate in the SBUV-only analyses caused by transport errors in the forecast. The global improvements in the assimilation lead to local improvements when compared against individual measured ozone profiles, where vertical structures are determined by height dependence in horizontal advection from diverse regions. The spatio-temporal variability in the assimilation is more realistic when MIPAS data are included. Experiments to examine the impacts of temporal gaps in the MIPAS data reveal a 'memory' of 5-10 days in the transport-dominated lower stratosphere. In the middle stratosphere, the impact of missing MIPAS data is more complex; transport errors cause a large initial impact followed by ozone values typical of SBUV assimilation. C1 NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Earth & Space Data Comp Div, Greenbelt, MD 20771 USA. Sci Applicat Int Corp, Mclean, VA 22102 USA. RP Wargan, K (reprint author), NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Code 610-1, Greenbelt, MD 20771 USA. EM wargan@gmao.gsfc.nasa.gov RI Rood, Richard/C-5611-2008; Stajner, Ivanka/B-5228-2009; Pawson, Steven/I-1865-2014; OI Rood, Richard/0000-0002-2310-4262; Stajner, Ivanka/0000-0001-6103-3939; Pawson, Steven/0000-0003-0200-717X; Wargan, Krzysztof/0000-0002-3795-2983 NR 27 TC 24 Z9 24 U1 0 U2 4 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0035-9009 EI 1477-870X J9 Q J ROY METEOR SOC JI Q. J. R. Meteorol. Soc. PD OCT PY 2005 VL 131 IS 611 BP 2713 EP 2734 DI 10.1256/qj.04.184 PN A PG 22 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 986UT UT WOS:000233475900007 ER PT J AU Savijarvi, H Crisp, D Harri, AM AF Savijarvi, H Crisp, D Harri, AM TI Effects of CO2 and dust on present-day solar radiation and climate on Mars SO QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY LA English DT Article DE climate sensitivity; radiative transfer; two-stream methods ID WAVE OPTICAL-PROPERTIES; MARTIAN ATMOSPHERE; BOUNDARY-LAYER; MULTIPLE-SCATTERING; THERMAL STRUCTURE; SLOPE WINDS; APPROXIMATIONS; PATHFINDER; SURFACE; LANDER AB A comprehensive spectrum-resolving radiative transfer model (SRM) was used to simulate the average, present-day, solar radiation field on Mars. A CO2-only 6 hPa Martian atmosphere absorbs about 1% of zenith solar radiation, producing a modest heating rate of 4-5 K day(-1) in the lowest 10 km. The trace gases have an insignificant effect but airborne dust reduces the downwelling solar flux effectively, and the reflected flux somewhat less. This produces an anti-greenhouse trend (cooling at the surface, warming within the atmosphere, reflection at the top), which increases strongly with the dust load. For instance, with dust visible optical depth of unity and sun in zenith, the surface solar irradiation is attenuated by 26% and the solar heating rate increases to about 70 K day(-1) in the lowest 25 km. The numbers are however strongly dependent on the optical properties of the dust, which are not known very well. Several fast two-stream methods for dust were compared with the SRM results. Their common systematic errors were reduced by a simple, physically-based correction. The global albedo of Mars was then studied as a function of dust load, dust optics and surface albedo. The crossover from added airborne dust tending to make the whole planet look whiter or darker occurred at surface albedo of about 35%, nearly independently of the dust load. We demonstrate, however, that this value is sensitive to the optical properties of the assumed dust. C1 Univ Helsinki, Div Atmospher Sci, Dept Phys Sci, FIN-00014 Helsinki, Finland. Jet Propuls Lab, Pasadena, CA 91109 USA. Finnish Meteorol Inst, Helsinki, Finland. RP Savijarvi, H (reprint author), Univ Helsinki, Div Atmospher Sci, Dept Phys Sci, POB 64, FIN-00014 Helsinki, Finland. EM hannu.savijarvi@helsinki.fi RI Harri, Ari-Matti/C-7142-2012 OI Harri, Ari-Matti/0000-0001-8541-2802 NR 27 TC 16 Z9 16 U1 0 U2 6 PU ROYAL METEOROLOGICAL SOC PI READING PA 104 OXFORD ROAD, READING RG1 7LJ, BERKS, ENGLAND SN 0035-9009 J9 Q J ROY METEOR SOC JI Q. J. R. Meteorol. Soc. PD OCT PY 2005 VL 131 IS 611 BP 2907 EP 2922 DI 10.1256/qj.04.09 PN A PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 986UT UT WOS:000233475900016 ER PT J AU Dee, DP AF Dee, D. P. TI Bias and data assimilation SO QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY LA English DT Article; Proceedings Paper CT 4th WMO International Symposium on Assimilation of Observations in Meteorology and Oceanography CY APR 18-22, 2005 CL Prague, CZECH REPUBLIC SP WMO, NASA, NCAR DE adaptive bias correction; bias-aware; bias-blind; Kalman filter; model bias; observation bias; parameter estimation; systematic errors; weak-constraint 4D-Var ID FORECAST BIAS; NAVDAS-AR; MODEL; FORMULATION; SYSTEM; ERRORS; TESTS AB All data assimilation systems are affected by biases, caused by problems with the data, by approximations in the observation operators used to simulate the data, by limitations of the assimilating model, or by the assimilation methodology itself. A clear symptom of bias in the assimilation is the presence of systematic features in the analysis increments, such as large persistent mean values or regularly recurring spatial structures. Bias can also be detected by monitoring statistics of observed-minus-background residuals for different instruments. Bias-aware assimilation methods are designed to estimate and correct systematic errors jointly with the model state variables. Such methods require attribution of a bias to a particular source, and its characterization in terms of some well-defined set of parameters. They can be formulated either in a variational or sequential estimation framework by augmenting the system state with the bias parameters. C1 NASA, Global Modeling & Assimilat Off, Goddard Space Flight Ctr, Washington, DC 20546 USA. RP Dee, DP (reprint author), European Ctr Medium Range Weather Forecasts, Shinfield Pk, Reading RG2 9AX, Berks, England. EM Dick.Dee@ecmwf.int NR 40 TC 234 Z9 239 U1 2 U2 17 PU ROYAL METEOROLOGICAL SOC PI READING PA 104 OXFORD ROAD, READING RG1 7LJ, BERKS, ENGLAND SN 0035-9009 J9 Q J ROY METEOR SOC JI Q. J. R. Meteorol. Soc. PD OCT PY 2005 VL 131 IS 613 BP 3323 EP 3343 DI 10.1256/qj.05.137 PN C PG 21 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 075OV UT WOS:000239896000010 ER PT J AU George, K Willingham, V Cucinotta, FA AF George, K Willingham, V Cucinotta, FA TI Stability of chromosome aberrations in the blood lymphocytes of astronauts measured after space flight by FISH chromosome painting SO RADIATION RESEARCH LA English DT Article ID IN-SITU HYBRIDIZATION; FOLLOW-UP; RADIATION ACCIDENT; DICENTRIC FREQUENCIES; BIOLOGICAL DOSIMETRY; TRANSLOCATION; EXPOSURE; IRRADIATION; PERSISTENCE; VICTIMS AB Follow-up measurements of chromosome aberrations in the blood lymphocytes of astronauts were performed by FISH chromosome painting at various intervals from 5 months to more than 5 years after space flight and compared to preflight baseline measurements. For five of the six astronauts studied, the analysis of individual time courses for translocations revealed a temporal decline of yields with half-lives ranging from 10 to 58 months. yield of exchanges remained unchanged for the sixth astronaut during an observation period of 5 months after flight. These results may indicate complications, with the use of stable aberrations for retrospective dose reconstruction, and the differences in the decay time may reflect individual variability in risk from space radiation exposure. C1 Wyle Labs, Houston, TX 77058 USA. NASA, Johnson Space Ctr, Houston, TX 77058 USA. RP George, K (reprint author), Wyle Labs, 1290 Hercules,Suite 120, Houston, TX 77058 USA. EM kerry.a.george1@jsc.nasa.gov NR 32 TC 20 Z9 21 U1 1 U2 2 PU RADIATION RESEARCH SOC PI OAK BROOK PA 820 JORIE BOULEVARD, OAK BROOK, IL 60523 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD OCT PY 2005 VL 164 IS 4 BP 474 EP 480 DI 10.1667/RR3323.1 PN 2 PG 7 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA 967VU UT WOS:000232120100005 PM 16187752 ER PT J AU Desai, N Davis, E O'Neill, P Durante, M Cucinotta, EA Wu, H AF Desai, N Davis, E O'Neill, P Durante, M Cucinotta, EA Wu, H TI Immunofluorescence detection of clustered gamma-H2AX foci induced by HZE-particle radiation SO RADIATION RESEARCH LA English DT Article ID DOUBLE-STRAND BREAKS; HISTONE H2AX; CELLS; INDUCTION; REPAIR; PHOSPHORYLATION; IRRADIATION; DOMAINS; DAMAGE; SITES AB We studied the spatial and temporal distributions of foci of the phosphorylated form of the histone protein H2AX (gamma-H2AX), which is known to be activated by double-strand breaks after irradiation of human fibroblast cells with high-energy silicon (54 keV/mu m) and iron (176 keV/mu m) ions. Here we present data obtained with the ion path parallel to a monolayer of human fibroblast cells that leads to gamma-H2AX aggregates in the shape of streaks stretching over several micrometers in an x/y plane, thus enabling the analysis of the fluorescence distributions along the ion trajectories. Qualitative analyses of these distributions provide insights into DNA damage processing kinetics for high charge and energy (HZE) ions, including evidence of increased clustering of DNA damage and slower processing with increasing LET. (c) 2005 by Radiation Research Society. C1 NASA, Johnson Space Ctr, Houston, TX 77058 USA. Wyle Labs, Houston, TX USA. MRC, Radiat & Genome Stabil Unit, Harwell, Didcot, England. Univ Naples, Dept Phys, Naples, Italy. RP Cucinotta, EA (reprint author), NASA, Johnson Space Ctr, Mail Code SK, Houston, TX 77058 USA. EM francis.a.cucinotta@nasa.gov RI Durante, Marco/K-1315-2014 NR 17 TC 74 Z9 76 U1 0 U2 5 PU RADIATION RESEARCH SOC PI OAK BROOK PA 820 JORIE BOULEVARD, OAK BROOK, IL 60523 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD OCT PY 2005 VL 164 IS 4 BP 518 EP 522 DI 10.1667/RR3431.1 PN 2 PG 5 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA 967VU UT WOS:000232120100013 PM 16187760 ER PT J AU Durante, M George, K Gialanella, G Grossi, G La Tessa, C Manti, L Miller, J Pugliese, M Scampoli, P Cucinotta, FA AF Durante, M George, K Gialanella, G Grossi, G La Tessa, C Manti, L Miller, J Pugliese, M Scampoli, P Cucinotta, FA TI Cytogenetic effects of high-energy iron ions: Dependence on shielding thickness and material SO RADIATION RESEARCH LA English DT Article ID HUMAN-LYMPHOCYTES; BIOLOGICAL EFFECTIVENESS; CHROMOSOMAL-ABERRATIONS; RADIATION; PROTECTION; METAPHASE; INDUCTION AB We report results for chromosomal aberrations in human peripheral blood lymphocytes after they were exposed to high-energy iron ions with or without shielding at the HIMAC, AGS and NSRL accelerators. Isolated lymphocytes were exposed to iron ions with energies between 200 and 5000 MeV/nucleon in the 0.1-1-Gy dose range. Shielding materials consisted of polyethylene, lucite (PMMA), carbon, aluminum and lead, with mass thickness ranging from 2 to 30 g/cm(2). After exposure, lymphocytes were stimulated to grow in vitro, and chromosomes were prematurely condensed using a phosphatase inhibitor (calyculin A). Aberrations were scored using FISH painting. The yield of total interchromosomal exchanges (including dicentrics, translocations and complex rearrangements) increased linearly with dose or fluence in the range studied. Shielding decreased the effectiveness per unit dose of iron ions. The highest RBE value was measured with the 1 GeV/nucleon iron-ion beam at NSRL. However, the RBE for the induction of aberrations apparently is not well correlated with the mean LET. When shielding thickness was increased, the frequency of aberrations per particle incident on the shield increased for the 500 MeV/nucleon ions and decreased for the 1 GeV/nucleon ions. Maximum variation at equal mass thickness was obtained with light materials (polyethylene, carbon or PMMA). Variations in the yield of chromosomal aberrations per iron particle incident on the shield follow variations in the dose per incident particle behind the shield but can be modified by the different RBE of the mixed radiation field produced by nuclear fragmentation. The results suggest that shielding design models should be benchmarked using both physics and biological data. (c) 2005 by Radiation Research Society. C1 Univ Naples Federico II, Dept Phys, I-80126 Naples, Italy. Ist Nazl Fis Nucl, Sez Napoli, I-80125 Naples, Italy. Wyle Labs, Houston, TX USA. Chalmers Univ Technol, S-41296 Gothenburg, Sweden. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. RP Durante, M (reprint author), Univ Naples Federico II, Dipartimento Sci Fis, Via Cintia, I-80126 Naples, Italy. EM Marco.Durante@na.infn.it RI Durante, Marco/K-1315-2014; OI Durante, Marco/0000-0002-4615-553X NR 17 TC 36 Z9 36 U1 0 U2 5 PU RADIATION RESEARCH SOC PI OAK BROOK PA 820 JORIE BOULEVARD, OAK BROOK, IL 60523 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD OCT PY 2005 VL 164 IS 4 BP 571 EP 576 DI 10.1667/RR3362.1 PN 2 PG 6 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA 967VU UT WOS:000232120100023 PM 16187790 ER PT J AU Rosario-Castro, BI Contes, EJ Perez-Davis, ME Cabrera, CR AF Rosario-Castro, BI Contes, EJ Perez-Davis, ME Cabrera, CR TI Attachment of single-wall carbon nanotubes on platinum surfaces by self-assembling techniques SO REVIEWS ON ADVANCED MATERIALS SCIENCE LA English DT Article; Proceedings Paper CT 2nd International Conference on Nanomaterials and Nanotechnologies CY JUN 14-18, 2005 CL Crete, GREECE ID LOGIC-CIRCUITS; FUNCTIONALIZATION; TRANSISTORS; HYDROGEN; STORAGE; TIPS AB Self-assembled monolayers (SAMs) technique was used to adsorb 4-aminothiophenol (4-ATP) on platinum electrodes, in order to obtain an amino-terminated SAM as the base for the attachment of single-wall carbon nanotubes (SWNTs). Previously purified SWNTs were oxidized with strong acids to obtain open ended nanotubes terminated with carboxylic acid groups. These acid-treated SWNTs were attached, by a condensation reaction, to the amino terminated SAM. Xray photoelectron spectroscopy (XPS) and infrared (IR) spectroscopy characterization was employ to follow SWNTs functionalization throughout purification and acid-treatment processes. The characterization of SWNTs attached over modified Pt electrodes was performed using reflection-absorption infrared spectroscopy (RAIR), XPS, and scanning electron microscopy (SEM). The results obtained suggest the successful attachment of SWNTs through the formation of amide bonds between SWNTs and the amino-terminated SAM. C1 Univ Puerto Rico, Dept Chem, San Juan, PR 00931 USA. Univ Puerto Rico, Ctr Nanoscale Mat, San Juan, PR 00931 USA. NASA John H Glenn Res Ctr, Electrochem Branch, Cleveland, OH 44135 USA. RP Cabrera, CR (reprint author), Univ Puerto Rico, Dept Chem, POB 23346, San Juan, PR 00931 USA. EM ccabrera@cnnet.upr.edu OI Cabrera, Carlos/0000-0002-3342-8666 NR 25 TC 20 Z9 20 U1 1 U2 5 PU INST PROBLEMS MECHANICAL ENGINEERING-RUSSIAN ACAD SCIENCES PI ST PTERSBURG PA BOLSHOJ 61, VAS OSTROV, ST PTERSBURG, 199178, RUSSIA SN 1606-5131 J9 REV ADV MATER SCI JI Rev. Adv. Mater. Sci. PD OCT PY 2005 VL 10 IS 4 SI SI BP 381 EP 386 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary SC Science & Technology - Other Topics; Materials Science GA 979ZR UT WOS:000232984200018 ER PT J AU Wang, RX Xu, JC Juliette, L Castilleja, A Love, J Sung, SY Zhau, HE Goodwin, TJ Chung, LWK AF Wang, RX Xu, JC Juliette, L Castilleja, A Love, J Sung, SY Zhau, HE Goodwin, TJ Chung, LWK TI Three-dimensional co-culture models to study prostate cancer growth, progression, and metastasis to bone SO SEMINARS IN CANCER BIOLOGY LA English DT Review DE cancer-stromal interaction; epithelial to mesenchymal transition; 3-dimensional cell culture; prostate cancer bone metastasis; bone mineralization; cancer metastasis ID EPITHELIAL-MESENCHYMAL TRANSITIONS; CARCINOMA-CELL-LINE; MAMMARY-GLAND; TUMOR-GROWTH; IN-VITRO; HOST MICROENVIRONMENT; ANDROGEN-INDEPENDENCE; VASCULOGENIC MIMICRY; CHORIOALLANTOIC MEMBRANE; DIFFERENTIAL EXPRESSION AB Cancer-stromal interaction results in the co-evolution of both the cancer cells and the surrounding host stromal cells. As a consequence of this interaction, cancer cells acquire increased malignant potential and stromal cells become more inductive. In this review we suggest that cancer-stromal interaction can best be investigated by three-dimensional (3D) co-culture models with the results validated by clinical specimens. We showed that 3D culture promoted bone formation in vitro, and explored for the first time, with the help of the astronauts of the Space Shuttle Columbia, the co-culture of human prostate cancer and bone cells to further understand the interactions between these cells. Continued exploration of cancer growth under 3D conditions will rapidly lead to new discoveries and ultimately to improvements in the treatment of men with hormonal refractory prostate cancer. (c) 2005 Elsevier Ltd. All rights reserved. C1 Emory Univ, Sch Med, Dept Urol, Mol Urol & Therapeut Program, Atlanta, GA 30322 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Wyle Labs, Houston, TX 77058 USA. RP Wang, RX (reprint author), Emory Univ, Sch Med, Dept Urol, Mol Urol & Therapeut Program, Atlanta, GA 30322 USA. FU NCI NIH HHS [CA82739, CA098912] NR 130 TC 51 Z9 55 U1 2 U2 21 PU ACADEMIC PRESS LTD ELSEVIER SCIENCE LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 1044-579X J9 SEMIN CANCER BIOL JI Semin. Cancer Biol. PD OCT PY 2005 VL 15 IS 5 BP 353 EP 364 DI 10.1016/j.semcancer.2005.05.005 PG 12 WC Oncology SC Oncology GA 966KO UT WOS:000232018800004 PM 15982899 ER PT J AU DellaCorte, C AF DellaCorte, C TI Calgary is calling ... SO TRIBOLOGY & LUBRICATION TECHNOLOGY LA English DT Editorial Material C1 NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP DellaCorte, C (reprint author), NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. EM cdellacorte@stle.org NR 0 TC 0 Z9 0 U1 0 U2 1 PU SOC TRIBOLOGISTS & LUBRICATION ENGINEERS PI PARK RIDGE PA 840 BUSSE HIGHWAY, PARK RIDGE, IL 60068 USA SN 0024-7154 J9 TRIBOL LUBR TECHNOL JI Tribol. Lubr. Technol. PD OCT PY 2005 VL 61 IS 10 BP 6 EP 6 PG 1 WC Engineering, Mechanical SC Engineering GA 974TV UT WOS:000232615200002 ER PT J AU Dimofte, F Fleming, DP Anderson, WJ Klein, RC AF Dimofte, F Fleming, DP Anderson, WJ Klein, RC TI Test of a fluid-film wave bearing at 350 degrees C with liquid lubricants SO TRIBOLOGY TRANSACTIONS LA English DT Article DE fluid-film bearing; wave bearing; high temperature; PFPE-K fluids AB A novel fluid-film wave bearing has been run at a higher temperature (350 degrees C) than ever before with a perfluoropolyether (PFPE)-K liquid lubricant. Additionally, the wave journal bearing (45 mm diameter and 24 mm long) completed an 8-h endurance test at the NASA Glenn Research Center The lubricant was PFPE-K XHT 500. After being maintained at 350 degrees C for 8 h, the bearing temperature was raised to 356 degrees C for the last 30 min of the run. The speed was 29,000 rpm and the load ranged from 2670 to 3560 N. The bearing was perfectly stable both dynamically and thermally. The observed temperature was more than 150 degrees C above that run with current turbine engine lubricants. The use of high-temperature bearings as tested here would allow efficiency increases of more than 5% in aero or terrestrial turbine engines. C1 NASTEC Inc, Cleveland, OH 44114 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Dimofte, F (reprint author), NASTEC Inc, Cleveland, OH 44114 USA. NR 19 TC 2 Z9 3 U1 1 U2 1 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 1040-2004 J9 TRIBOL T JI Tribol. Trans. PD OCT-DEC PY 2005 VL 48 IS 4 BP 515 EP 521 DI 10.1080/05698190500313585 PG 7 WC Engineering, Mechanical SC Engineering GA 001MD UT WOS:000234536400011 ER PT J AU Rogers, WE Wittmann, PA Wang, DWC Clancy, RM Hsu, YL AF Rogers, WE Wittmann, PA Wang, DWC Clancy, RM Hsu, YL TI Evaluations of global wave prediction at the fleet numerical meteorology and oceanography center SO WEATHER AND FORECASTING LA English DT Article ID BUOY DATA; MODEL; SYSTEMS; SCALE; SEAS AB It is a major challenge to determine whether bias in operational global wave predictions is predominately due to the wave model itself (internal error) or due to errors in wind forcing (an external error). Another challenge is to characterize bias attributable to errors in wave model physics (e.g., input, dissipation, and nonlinear transfer). In this study, hindcasts and an evaluation methodology are constructed to address these challenges. The bias of the wave predictions is evaluated with consideration of the bias of four different wind forcing fields [two of which are supplemented with the NASA Quick Scatterometer (QuikSCAT) measurements]. It is found that the accuracy of the Fleet Numerical Meteorology and Oceanography Center's operational global wind forcing has improved to the point where it is unlikely to be the primary source of error in the center's global wave model (WAVEWATCH-III). The hindcast comparisons are specifically designed to minimize systematic errors from numerics and resolution. From these hindcasts, insight into the physics-related bias in the global wave model is possible: comparison to in situ wave data suggests an overall positive bias at northeast Pacific locations and an overall negative bias at northwest Atlantic locations. Comparison of frequency bands indicates a tendency by the model physics to overpredict energy at higher frequencies and underpredict energy at lower frequencies. C1 Stennis Space Ctr, USN, Res Lab, Oceanol Div, Stennis Space Ctr, MS USA. Fleet Numer Meteorol & Oceanog Ctr, Monterey, CA USA. RP Rogers, WE (reprint author), NRL Code 7322 Bldg 1009, Stennis Space Ctr, MS 39529 USA. EM rogers@nrlssc.navy.mil NR 45 TC 13 Z9 13 U1 0 U2 5 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0882-8156 J9 WEATHER FORECAST JI Weather Forecast. PD OCT PY 2005 VL 20 IS 5 BP 745 EP 760 DI 10.1175/WAF882.1 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 981JK UT WOS:000233084700003 ER PT J AU Flom, Y AF Flom, Y TI Brazing in space: Enabling the next frontier SO WELDING JOURNAL LA English DT Article AB Vacuum brazing is a promising joining process for the assembly of large truss structures in space. C1 NASA, Mat Engn Branch, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Flom, Y (reprint author), NASA, Mat Engn Branch, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM yury.a.flom@nasa.gov NR 7 TC 3 Z9 4 U1 0 U2 0 PU AMER WELDING SOC PI MIAMI PA 550 N W LEJEUNE RD, MIAMI, FL 33126 USA SN 0043-2296 J9 WELD J JI Weld. J. PD OCT PY 2005 VL 84 IS 10 BP 25 EP 29 PG 5 WC Metallurgy & Metallurgical Engineering SC Metallurgy & Metallurgical Engineering GA 971IN UT WOS:000232377500011 ER PT J AU Hart, WD Spinhirne, JD Palm, SP Hlavka, DL AF Hart, WD Spinhirne, JD Palm, SP Hlavka, DL TI Height distribution between cloud and aerosol layers from the GLAS spaceborne lidar in the Indian Ocean region SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID SUPPRESSION; PARAMETERS; POLLUTION AB The Geoscience Laser Altimeter System (GLAS), a nadir pointing lidar on the Ice Cloud and land Elevation Satellite (ICESat) launched in 2003, now provides important new global measurements of the relationship between the height distribution of cloud and aerosol layers. GLAS data have the capability to detect, locate, and distinguish between cloud and aerosol layers in the atmosphere up to 40 km altitude. The data product algorithm tests the product of the maximum attenuated backscatter coefficient b'(r) and the vertical gradient of b'(r) within a layer against a predetermined threshold. An initial case result for the critical Indian Ocean region is presented. From the results the relative height distribution between collocated aerosol and cloud shows extensive regions where cloud formation is well within dense aerosol scattering layers at the surface. C1 NASA, Sci Syst & Applicat Inc, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Hart, WD (reprint author), NASA, Sci Syst & Applicat Inc, Goddard Space Flight Ctr, Code 613-1, Greenbelt, MD 20771 USA. EM billhart@agnes.gsfc.nasa.gov NR 12 TC 18 Z9 18 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 SEP 30 PY 2005 VL 32 IS 22 AR L22S06 DI 10.1029/2005GL023671 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 971PI UT WOS:000232396000001 ER PT J AU Spinhirne, JD Palm, SP Hart, WD AF Spinhirne, JD Palm, SP Hart, WD TI Antarctica cloud cover for October 2003 from GLAS satellite lidar profiling SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID SOUTH-POLE; RADIATION; ALTIMETRY; ICE AB Bright surfaces and low surface temperature limit the study of Antarctica cloud cover by passive techniques. Starting in 2003 the Geoscience Laser Altimeter System (GLAS) provides the first measurements of polar clouds by satellite lidar. From the GLAS data the presence and height of all clouds are detected, and in the case of transmissive clouds that predominate in the Antarctica, the thickness is also found. Initial results for October 2003 data are summarized. There are two basic cloud types profiled: stratus below 3 km and cirrus form clouds with cloud top altitude and thickness tending at 12 km and 1.3 km. Zonal average cloud fraction varies from over 93% for ocean and coastal regions to a consistent average of 40% over the East Antarctic plateau and 60 - 90% over West Antarctica. Differences between the zonal average GLAS and MODIS cloud fractions are as much as 40% over the continent. C1 NASA, Lab Atmospheres 613 1, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Sci Syst Applicat Inc, Lanham, MD 20706 USA. RP Spinhirne, JD (reprint author), NASA, Lab Atmospheres 613 1, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. EM jspin@virl.gsfc.nasa.gov NR 14 TC 26 Z9 26 U1 0 U2 2 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 SEP 30 PY 2005 VL 32 IS 22 AR L22S05 DI 10.1029/2005GL023782 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 971PI UT WOS:000232396000002 ER PT J AU Farrugia, CJ Matsui, H Kucharek, H Torbert, RB Smith, CW Jordanova, VK Ogilvie, KW Lepping, RP Berdichevsky, DB Terasawa, T Kasper, J Mukai, T Saito, Y Skoug, R AF Farrugia, CJ Matsui, H Kucharek, H Torbert, RB Smith, CW Jordanova, VK Ogilvie, KW Lepping, RP Berdichevsky, DB Terasawa, T Kasper, J Mukai, T Saito, Y Skoug, R TI Interplanetary coronal mass ejection and ambient interplanetary magnetic field correlations during the Sun-Earth connection events of October-November 2003 SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID WIND PLASMA CORRELATIONS; SOLAR-WIND; GEOMAGNETIC-ACTIVITY; IMP-8 OBSERVATIONS; CLOUDS; ISEE-3; STORMS; SHOCK; MAGNETOSPHERE; DISTURBANCES AB [1] Magnetic field observations made during 28 October to 1 November 2003, which included two fast interplanetary coronal mass ejections (ICMEs), allow a study of correlation lengths of magnetic field parameters for two types of interplanetary (IP) structures: ICMEs and ambient solar wind. Further, they permit the extension of such investigations to the magnetosheath and to a distance along the Sun-Earth line ( X) of about 400 RE. Data acquired by three spacecraft are examined: ACE, in orbit around the L1 point; Geotail, traveling eastward in the near-Earth solar wind ( at R similar to 30 R-E); and Wind, nominally in the distant geomagnetic tail ( R similar to - 160 R-E) but making repeated excursions into the magnetosheath/ solar wind due to the flapping of the tail. Analyses are presented in both time and frequency domains. We find significant differences in the cross-correlation/coherence properties of the ambient interplanetary magnetic field ( IMF) and ICME parameters. For the ambient IMF, we find high coherence to be confined to low frequencies, consistent with other studies. In contrast, ICME magnetic field parameters remain generally coherent up to much higher frequencies. Scale lengths of ICME magnetic field parameters are in excess of 400 R-E. High speeds of similar to 1700 km s(-1) are inferred from the plot of phase difference versus frequency, consistent with that obtained from plasma instruments. To strengthen these results and to extend them to include dependence on the distance perpendicular to the Sun-Earth line (Y), we examine a 28-day interval in year 2001 characterized by a sequence of 10 ICMEs and containing roughly equal ambient solar wind and ICME time intervals. ACE-Wind X and Y separations were similar to 220 and similar to 250 R-E, respectively. We find good coherence/correlation alternating with poor values. In particular, we find that in general ICME coherence/correlation lengths along Y are larger by a factor of 3 - 5 than those quoted in the literature for ambient solar wind parameters. Our findings are good news for the space weather effort, which depends crucially on predicting the arrival of large events, since they make possible the placement of upstream monitors to give a longer lead time than at L1. C1 Univ New Hampshire, Inst Study Earth Oceans & Space, Ctr Space Sci, Durham, NH 03824 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Tokyo, Dept Earth & Planetary Sci, Bunkyo Ku, Tokyo 1130033, Japan. MIT, Ctr Space Res, Cambridge, MA 02139 USA. Japan Aerosp Explorat Agcy, Kanagawa 2298510, Japan. Los Alamos Natl Lab, Grp ISR 1, Los Alamos, NM 87545 USA. RP Farrugia, CJ (reprint author), Univ New Hampshire, Inst Study Earth Oceans & Space, Ctr Space Sci, Durham, NH 03824 USA. EM charlie.farrugia@unh.edu RI Kasper, Justin/D-1152-2010; OI Kasper, Justin/0000-0002-7077-930X; Jordanova, Vania/0000-0003-0475-8743 NR 53 TC 15 Z9 15 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 SEP 30 PY 2005 VL 110 IS A9 AR A09S13 DI 10.1029/2004JA010968 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 973HD UT WOS:000232512600006 ER PT J AU Gopalswamy, N Barbieri, L Cliver, EW Lu, G Plunkett, SP Skoug, RM AF Gopalswamy, N Barbieri, L Cliver, EW Lu, G Plunkett, SP Skoug, RM TI Introduction to violent Sun-Earth connection events of October-November 2003 SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article; Proceedings Paper CT Fall Meeting of the American-Geophysical-Union CY DEC 08-12, 2003 CL San Francisco, CA SP Amer Geophys Union AB [1] The solar-terrestrial events of late October and early November 2003, popularly referred to as the Halloween storms, represent the best observed cases of extreme space weather activity observed to date and have generated research covering multiple aspects of solar eruptions and their space weather effects. In the following article, which serves as an abstract for this collective research, we present highlights taken from 61 of the 74 papers from the Journal of Geophysical Research, Geophysical Research Letters, and Space Weather which are linked under this special issue. ( An overview of the 13 associated papers published in Geophysics Research Letters is given in the work of Gopalswamy et al. (2005a)). C1 NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Greenbelt, MD 20771 USA. USAF, Res Lab, Space Vehicles Directorate, Bedford, MA 01731 USA. Natl Ctr Atmospher Res, High Altitude Observ, Boulder, CO 80301 USA. USN, Res Lab, Washington, DC 20375 USA. Los Alamos Natl Lab, Grp NIS1, Los Alamos, NM 87545 USA. RP NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Code 444, Greenbelt, MD 20771 USA. EM gopals@fugee.gsfc.nasa.gov RI Lu, Gang/A-6669-2011; Gopalswamy, Nat/D-3659-2012 NR 54 TC 30 Z9 31 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 SEP 30 PY 2005 VL 110 IS A9 AR A09S00 DI 10.1029/2005JA011268 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 973HD UT WOS:000232512600011 ER PT J AU Lopez-Puertas, M Funke, B Gil-Lopez, S von Clarmann, T Stiller, GP Hopfner, M Kellmann, S Tsidu, GM Fischer, H Jackman, CH AF Lopez-Puertas, M Funke, B Gil-Lopez, S von Clarmann, T Stiller, GP Hopfner, M Kellmann, S Tsidu, GM Fischer, H Jackman, CH TI HNO3, N2O5, and ClONO2 enhancements after the October-November 2003 solar proton events SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID MIDDLE-ATMOSPHERE; STRATOSPHERE; CHEMISTRY; WINTER; OZONE AB [1] The large solar storm in October - November 2003 produced enormous amounts of high-energy protons which reached the Earth and penetrated into the middle atmosphere in the polar regions. At this time, the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) on board the Environmental Satellite (ENVISAT) was observing the atmosphere in the 6 - 68 km altitude range. MIPAS observed significant enhancements of the NOy components HNO3, N2O5, and ClONO2 in the northern polar stratosphere after the intense solar proton events. Two distinct HNO3 enhancements were observed. An instantaneous increase of 1 - 2 ppbv was observed immediately after the SPEs and is attributed to gas-phase chemistry: NO2 + OH + M --> HNO3 + M, accelerated by SPE-produced excess OH. A very large second increase of 1 - 5 ppbv started around 10 November and lasted until the end of December. It is attributed to NOx (NO + NO2) produced in the mesosphere during the major SPEs in late October/early November and then transported downward during November and December, partially converted to N2O5 in the upper stratosphere, which finally formed HNO3 via ion cluster reactions. N2O5 was observed to increase by 0.1 - 0.4 ppbv 1 - 3 days after the major SPEs and reached down to 30 km altitude. A second, more pronounced N2O5 enhancement of up to 1.2 ppbv at 40 km appeared about 12 - 13 days after the major SPEs. With a delay of 1 - 2 days after the major SPEs ClONO2 increased by up to 0.4 ppbv (40%) at 32 km altitude. NOy enhancements in the Southern Hemisphere were generally less pronounced. C1 CSIC, Inst Astrofis Andalucia, E-18080 Granada, Spain. Forschungszentrum Karlsruhe, Inst Meteorol & Klimaforsch, D-76021 Karlsruhe, Germany. Univ Karlsruhe, Inst Meteorol & Klimaforsch, D-76021 Karlsruhe, Germany. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP CSIC, Inst Astrofis Andalucia, Apartado Postal 3004, E-18080 Granada, Spain. EM puertas@iaa.es RI Hopfner, Michael/A-7255-2013; Stiller, Gabriele/A-7340-2013; von Clarmann, Thomas/A-7287-2013; Lopez Puertas, Manuel/M-8219-2013; Jackman, Charles/D-4699-2012; Funke, Bernd/C-2162-2008 OI Hopfner, Michael/0000-0002-4174-9531; Stiller, Gabriele/0000-0003-2883-6873; von Clarmann, Thomas/0000-0003-2219-3379; Lopez Puertas, Manuel/0000-0003-2941-7734; Funke, Bernd/0000-0003-0462-4702 NR 21 TC 45 Z9 47 U1 2 U2 7 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 SEP 30 PY 2005 VL 110 IS A9 AR A09S44 DI 10.1029/2005JA011051 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 973HD UT WOS:000232512600009 ER PT J AU Lopez-Puertas, M Funke, B Gil-Lopez, S von Clarmann, T Stiller, GP Hopfner, M Kellmann, S Fischer, H Jackman, CH AF Lopez-Puertas, M Funke, B Gil-Lopez, S von Clarmann, T Stiller, GP Hopfner, M Kellmann, S Fischer, H Jackman, CH TI Observation of NOx enhancement and ozone depletion in the Northern and Southern Hemispheres after the October-November 2003 solar proton events SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID MIDDLE-ATMOSPHERE; NITRIC-OXIDE; MIPAS; VORTEX; CONSTITUENTS; MESOSPHERE; RETRIEVAL; MODEL AB [1] The large solar storms in October - November 2003 produced enormous solar proton events (SPEs) where high energetic particles reached the Earth and penetrated into the middle atmosphere in the polar regions. At this time, the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) was observing the atmosphere in the 6 - 68 km altitude range. MIPAS observations of NOx (NO + NO2) and O-3 of the period from 25 October to 14 November 2003 are the first global measurements of NOx species, covering both the summer ( daylight) and winter ( dark) polar regions during an SPE. Very large values of NOx in the upper stratosphere of 180 ppbv ( parts per billion by volume) have been measured, and a large asymmetry in northern and southern polar cap NOx enhancements was found. Arctic mean polar cap (> 60 degrees) NOx enhancements of 20 to 70 ppbv between 40 to 60 km lasted for at least 2 weeks, while the Antarctic mean NOx enhancement was between 10 and 35 ppbv and was halved after 2 weeks. Ozone shows depletion signatures associated with both HOx (H + OH + HO2) and NOx enhancements but at different timescales. Arctic lower mesospheric ( upper stratospheric) ozone is reduced by 50 - 70% ( 30 - 40%) for about 2 weeks after the SPEs. A smaller ozone depletion signal was observed in the Antarctic atmosphere. After the locally produced Arctic middle and upper stratospheric as well as mesospheric NOx enhancement, large amounts of NOx were observed until the end of December. These are explained by downward transport processes. These enhancements drastically declined with the mid-December stratospheric warming. Significant O3 depletion was observed inside the polar vortex in a wide altitude range during this period. From mid-January until the end of March 2004, MIPAS observed extraordinary high values of NO2 in the upper stratosphere of the northern polar region ( mean in-vortex values up to 350 ppbv at similar to 54 km), which seem to be caused by the unusually strong vortex and downward transport at that time together with an uncommonly large auroral activity starting with the solar storms in October - November and continuing over the winter. In-vortex ozone was observed to significantly decline in the mid-February to late March period above the 1750 K potential temperature level. C1 CSIC, Inst Astrofis Andalucia, E-18080 Granada, Spain. Forschungszentrum Karlsruhe, Inst Meteorol & Klimaforsch, D-76021 Karlsruhe, Germany. Univ Karlsruhe, Inst Meteorol & Klimaforsch, D-76021 Karlsruhe, Germany. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Lopez-Puertas, M (reprint author), CSIC, Inst Astrofis Andalucia, Apartado Postal 3004, E-18080 Granada, Spain. EM puertas@iaa.es RI Hopfner, Michael/A-7255-2013; Stiller, Gabriele/A-7340-2013; von Clarmann, Thomas/A-7287-2013; Lopez Puertas, Manuel/M-8219-2013; Jackman, Charles/D-4699-2012; Funke, Bernd/C-2162-2008; OI Hopfner, Michael/0000-0002-4174-9531; Stiller, Gabriele/0000-0003-2883-6873; von Clarmann, Thomas/0000-0003-2219-3379; Lopez Puertas, Manuel/0000-0003-2941-7734; Funke, Bernd/0000-0003-0462-4702; Gil-Lopez, Sergio/0000-0001-5584-345X; Gil-Lopez, Sergio/0000-0002-3867-5439 NR 43 TC 80 Z9 83 U1 2 U2 8 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 SEP 30 PY 2005 VL 110 IS A9 AR A09S43 DI 10.1029/2005JA011050 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 973HD UT WOS:000232512600008 ER PT J AU Reiner, MJ Jackson, BV Webb, DF Mizuno, DR Kaiser, ML Bougeret, JL AF Reiner, MJ Jackson, BV Webb, DF Mizuno, DR Kaiser, ML Bougeret, JL TI Coronal mass ejection kinematics deduced from white light (Solar Mass Ejection Imager) and radio (Wind/WAVES) observations SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID INTERPLANETARY SHOCKS; ENERGETIC PARTICLES; ELECTRON-DENSITY; WIND SPACECRAFT; 1 AU; BURSTS; TRACKING; EMISSIONS; ORIGIN; EVENT AB [1] White-light and radio observations are combined to deduce the coronal and interplanetary kinematics of a fast coronal mass ejection (CME) that was ejected from the Sun at about 1700 UT on 2 November 2003. The CME, which was associated with an X8.3 solar flare from W56 degrees, was observed by the Mauna Loa and Solar and Heliospheric Observatory (SOHO) Large-Angle Spectrometric Coronograph (LASCO) coronagraphs to 14 R-.. The measured plane-of-sky speed of the LASCO CME was 2600 km s(-1). To deduce the kinematics of this CME, we use the plane-of-sky white light observations from both the Solar Mass Ejection Imager (SMEI) all-sky camera on board the Coriolis spacecraft and the SOHO/LASCO coronagraph, as well as the frequency drift rate of the low-frequency radio data and the results of the radio direction-finding analysis from the WAVES experiment on the Wind spacecraft. In agreement with the in situ observations for this event, we find that both the white light and radio observations indicate that the CME must have decelerated significantly beginning near the Sun and continuing well into the interplanetary medium. More specifically, by requiring self-consistency of all the available remote and in situ data, together with a simple, but not unreasonable, assumption about the general characteristic of the CME deceleration, we were able to deduce the radial speed and distance time profiles for this CME as it propagated from the Sun to 1 AU. The technique presented here, which is applicable to mutual SMEI/WAVES CME events, is expected to provide a more complete description and better quantitative understanding of how CMEs propagate through interplanetary space, as well as how the radio emissions, generated by propagating CME/shocks, relate to the shock and CME. This understanding can potentially lead to more accurate predictions for the onset times of space weather events, such as those that were observed during this unique period of intense solar activity. C1 Catholic Univ Amer, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Calif San Diego, Ctr Astrophys & Space Sci, La Jolla, CA 92093 USA. Boston Coll, Inst Sci Res, Chestnut Hill, MA 02467 USA. NASA, Goddard Space Flight Ctr, Solar Syst Explorat Div, Greenbelt, MD 20771 USA. Observ Paris, Lab Etud Spatiales & Instrumentat Astrophys, F-92190 Meudon, France. RP Reiner, MJ (reprint author), Catholic Univ Amer, Code 695, Greenbelt, MD 20771 USA. EM reiner@urap.gsfc.nasa.gov NR 63 TC 13 Z9 13 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 SEP 30 PY 2005 VL 110 IS A9 AR A09S14 DI 10.1029/2004JA010943 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 973HD UT WOS:000232512600004 ER PT J AU Matsko, AB Savchenkov, AA Strekalov, D Maleki, L AF Matsko, AB Savchenkov, AA Strekalov, D Maleki, L TI Whispering gallery resonators for studying orbital angular momentum of a photon SO PHYSICAL REVIEW LETTERS LA English DT Article ID OPTICAL MICROSPHERE RESONATORS; BESSEL BEAMS; MODES; LIGHT; DIFFRACTION; MICROCAVITY; SCATTERING; ATOMS AB We propose a simple method for generation and detection of photons with nonzero angular momentum. The method utilizes high-quality factor ring resonators that transform a plane electromagnetic wave into a wave with nonzero angular momentum, and vice versa. We show that the method is especially promising for studying high-order Bessel beams, unreachable by other techniques. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Matsko, AB (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. RI Matsko, Andrey/A-1272-2007 NR 30 TC 25 Z9 26 U1 2 U2 11 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD SEP 30 PY 2005 VL 95 IS 14 AR 143904 DI 10.1103/PhysRevLett.95.143904 PG 4 WC Physics, Multidisciplinary SC Physics GA 969JG UT WOS:000232229800026 PM 16241656 ER PT J AU Eymin, C Hulot, G AF Eymin, C Hulot, G TI On core surface flows inferred from satellite magnetic data SO PHYSICS OF THE EARTH AND PLANETARY INTERIORS LA English DT Article DE core dynamics; core surface flow; secular variation; satellite magnetic data ID GEOMAGNETIC SECULAR VARIATION; TANGENTIALLY GEOSTROPHIC FLOW; FROZEN-FLUX ASSUMPTION; MANTLE BOUNDARY; EARTHS CORE; TORSIONAL OSCILLATIONS; ANGULAR-MOMENTUM; ORSTED DATA; OUTER-CORE; FIELD AB Satellite-data allows the magnetic field produced by the dynamo within the Earth's core to be imaged with much more accuracy than previously possible with only ground-based data. Changes in this magnetic field can in turn be used to make some inferences about the core surface flow responsible for them. In this paper, we investigate the improvement brought to core flow computation by new satellite-data based core magnetic field models. It is shown that the main limitation now encountered is no longer the (now high) accuracy of those models, but the "non-modelled secular variation" produced by interaction of the non-resolvable small scales of the core flow with the core field, and by interaction of the (partly) resolvable large scales of the core flow with the small scales of the core field unfortunately m asked by the crustal field. We show how this non-modelled secular variation can be taken into account to recover the largest scales of the core flow in a consistent way. We also investigate the uncertainties this introduces in core flows computed with the help of the frozen-flux and tangentially geostrophic assumptions. It turns out that flows with much more medium and small scales than previously thought are needed to explain the satellite-data-based core magnetic field models. It also turns out that a significant fraction of this flow unfortunately happens to be non-recoverable (being either "non-resolvable" because too small-scale, or "invisible", because in the kernel of the inverse method) even though it produces the detectable "non-modelled secular variation". Applying this to the Magsat (1980) to Orsted (2000) field changes leads us to conclude that a flow involving at least strong retrograde vortices below the Atlantic Hemisphere, some less-resolved prograde vortices below the Pacific Hemisphere, and some poorly resolved (and partly non-resolvable) polar vortices, is needed to explain the 1980-2000 satellite-era average secular variation. The characteristics of the fraction of the secular variation left unexplained by this flow are also discussed. (c) 2005 Elsevier B.V. All rights reserved. C1 Inst Phys Globe, CNRS, UMR 7577, Dept Geomagnetisme & Paleomagnetisme, F-75252 Paris, France. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Grenoble 1, Lab Geophys Interne & Tectonophys, F-38041 Grenoble, France. RP Hulot, G (reprint author), Inst Phys Globe, CNRS, UMR 7577, Dept Geomagnetisme & Paleomagnetisme, 4 Pl Jussieu, F-75252 Paris, France. EM gh@ipgp.jussieu.fr RI Hulot, Gauthier/A-5627-2011 NR 43 TC 63 Z9 63 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0031-9201 J9 PHYS EARTH PLANET IN JI Phys. Earth Planet. Inter. PD SEP 30 PY 2005 VL 152 IS 3 BP 200 EP 220 DI 10.1016/j.pepi.2005.06.009 PG 21 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 974UE UT WOS:000232616100005 ER PT J AU Chen, XX Vierling, L Deering, D AF Chen, XX Vierling, L Deering, D TI A simple and effective radiometric correction method to improve landscape change detection across sensors and across time SO REMOTE SENSING OF ENVIRONMENT LA English DT Article DE relative radiometric normalization; post-fire chronosequence; boreal forest; temporally invariant cluster; leaf area index; enhanced vegetation index; normalized difference vegetation index; reduced simple ratio; landscape detection ID LEAF-AREA INDEX; VEGETATION INDEXES; LAND-COVER; TM IMAGES; NORMALIZATION; FORESTS; MODIS; SENSITIVITY; REGRESSION; CANOPY AB Satellite data offer unrivaled utility in monitoring and quantifying large scale land cover change over time. Radiometric consistency among collocated multi-temporal imagery is difficult to maintain, however, due to variations in sensor characteristics, atmospheric conditions, solar angle, and sensor view angle that can obscure surface change detection. To detect accurate landscape change using multitemporal images, we developed a variation of the pseudoinvariant feature (PIF) normalization scheme: the temporally invariant cluster (TIC) method. Image data were acquired on June 9, 1990 (Landsat 4), June 20, 2000 (Landsat 7), and August 26, 2001 (Landsat 7) to analyze boreal forests near the Siberian city of Krasnoyarsk using the normalized difference vegetation index (NDVI), enhanced vegetation index (EVI), and reduced simple ratio (RSR). The temporally invariant cluster (TIC) centers were identified via a point density map of collocated pixel VIs from the base image and the target image, and a normalization regression line was created to intersect all TIC centers. Target image VI values were then recalculated using the regression function so that these two images could be compared using the resulting common radiometric scale. We found that EVI was very indicative of vegetation structure because of its sensitivity to shadowing effects and could thus be used to separate conifer forests from deciduous forests and grass/crop lands. Conversely, because NDVI reduced the radiometric influence of shadow, it did not allow for distinctions among these vegetation types. After normalization, correlations of NDVI and EVI with forest leaf area index (LAI) field measurements combined for 2000 and 2001 were significantly improved; the r(2) values in these regressions rose from 0.49 to 0.69 and from 0.46 to 0.61, respectively. An EVI "cancellation effect" where EVI was positively related to understory greenness but negatively related to forest canopy coverage was evident across a post fire chrono sequence with normalized data. These findings indicate that the TIC method provides a simple, effective and repeatable method to create radiometrically comparable data sets for remote detection of landscape change. Compared to some previous relative radiometric normalization methods, this new method does not require high level programming and statistical skills, yet remains sensitive to landscape changes occurring over seasonal and inter-annual time scales. In addition, the TIC method maintains sensitivity to subtle changes in vegetation phenology and enables normalization even when invariant features are rare. While this normalization method allowed detection of a range of land use, land cover, and phenological/biophysical changes in the Siberian boreal forest region studied here, it is necessary to further examine images representing a wide variety of ecoregions to thoroughly evaluate the TIC method against other normalization schemes. (C) 2005 Elsevier Inc. All rights reserved. C1 S Dakota Sch Mines & Technol, Inst Atmospher Sci, Rapid City, SD 57701 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Chen, XX (reprint author), USGS Natl Ctr Earth Observ & Sci, SAIC, 47914 252nd St, Sioux Falls, SD 57198 USA. EM xtichen@usgs.gov; leev@uidaho.edu; Donald.W.Deering@nasa.gov RI Vierling, Lee/E-6428-2010 OI Vierling, Lee/0000-0001-5344-1983 NR 40 TC 86 Z9 101 U1 4 U2 37 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 SEP 30 PY 2005 VL 98 IS 1 BP 63 EP 79 DI 10.1016/j.rse.2005.05.021 PG 17 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 970SM UT WOS:000232329900005 ER PT J AU Werdell, PJ Bailey, SW AF Werdell, PJ Bailey, SW TI An improved in-situ bio-optical data set for ocean color algorithm development and satellite data product validation SO REMOTE SENSING OF ENVIRONMENT LA English DT Review DE ocean color; satellite validation; algorithm development; SeaBASS; SeaWiFS; MODIS; bio-optics; remote sensing; water-leaving radiance; chlorophyll ID INHERENT OPTICAL-PROPERTIES; REMOTE-SENSING REFLECTANCE; MIDDLE ATLANTIC BIGHT; GULF-OF-MEXICO; CHLOROPHYLL CONCENTRATION; SEAWIFS DATA; TIME-SERIES; PHYTOPLANKTON PIGMENTS; SURFACE MEASUREMENTS; ACCESSORY PIGMENTS AB Global satellite ocean color instruments provide the scientific community a high-resolution means of studying the marine biosphere. Satellite data product validation and algorithm development activities both require the substantial accumulation of high-quality in-situ observations. The NASA Ocean Biology Processing Group maintains a local repository of in-situ marine bio-optical data, the SeaWiFS Biooptical Archive and Storage System (SeaBASS), to facilitate their ocean color satellite validation analyses. Data were acquired from SeaBASS and used to compile a large set of coincident radiometric observations and phytoplankton pigment concentrations for use in biooptical algorithm development. This new data set, the NASA bio-Optical Marine Algorithm Data set (NOMAD), includes over 3400 stations of spectral water-leaving radiances, surface irradiances, and diffuse downwelling attenuation coefficients, encompassing chlorophyll a concentrations ranging from 0.012 to 72.12 mg m(-3). Metadata, such as the date, time, and location of data collection, and ancillary data, including sea surface temperatures and water depths, accompany each record. This paper describes the assembly and evaluation of NOMAD, and further illustrates the broad geophysical range of stations incorporated into NOMAD. (C) 2005 Elsevier Inc. All rights reserved. C1 NASA, Goddard Space Flight Ctr, Sci Syst & Applicat Inc, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Futuretech Corp, Greenbelt, MD 20771 USA. RP Werdell, PJ (reprint author), NASA, Goddard Space Flight Ctr, Sci Syst & Applicat Inc, Greenbelt, MD 20771 USA. EM jeremy.werdell@gsfc.nasa.gov; sean.bailey@gsfc.nasa.gov RI Werdell, Jeremy/D-8265-2012; Bailey, Sean/D-3077-2017 OI Bailey, Sean/0000-0001-8339-9763 NR 92 TC 257 Z9 264 U1 4 U2 49 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 SEP 30 PY 2005 VL 98 IS 1 BP 122 EP 140 DI 10.1016/j.rse.2005.07.001 PG 19 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 970SM UT WOS:000232329900009 ER PT J AU von Savigny, C Kaiser, JW Bovensmann, H Burrows, JP McDermid, IS Leblanc, T AF von Savigny, C Kaiser, JW Bovensmann, H Burrows, JP McDermid, IS Leblanc, T TI Spatial and temporal characterization of SCIAMACHY limb pointing errors during the first three years of the mission SO ATMOSPHERIC CHEMISTRY AND PHYSICS LA English DT Article ID SCATTER MEASUREMENTS; O-3 PROFILES; OZONE; ULTRAVIOLET; RETRIEVAL; SATELLITE; EXPLORER; SPECTROMETER; VALIDATION; INSTRUMENT AB Limb scattering retrievals of atmospheric minor constituent profiles require highly accurate knowledge of the tangent heights during the measurements. The limb scattering measurements of the Scanning Imaging Absorption spectroMeter for Atmospheric CartograpHY (SCIAMACHY) on Envisat are affected by tangent height errors of up to 2 km. This contribution provides a summary of the temporal and spatial variation of the SCIAMACHY limb pointing errors during the first three years of the SCIAMACHY mission. The tangent height errors are retrieved from the limb measurements in the UV-B spectral range. A seasonal modulation of the monthly mean tangent height offsets is identified with amplitudes of 800 m ( 220 m) before ( after) the improvement of the Envisat orbit propagator model in December 2003. Even after the December 2003 orbit model improvement a constant offset component of about 1 km is present. Furthermore, pointing discontinuities are identified that coincide with the daily updates of the on-board orbit propagator model. In order to reduce the errors in ozone profile retrievals caused by pointing errors to less than 5%, the tangent heights have to be known to within 250 m. C1 Univ Bremen, IFE, IUP, D-28334 Bremen, Germany. Univ Zurich, Remote Sensing Labs, CH-8057 Zurich, Switzerland. CALTECH, Jet Prop Lab, Table Mt Facil, Wrightwood, CA 92397 USA. RP von Savigny, C (reprint author), Univ Bremen, IFE, IUP, Otto Hahn Allee 1, D-28334 Bremen, Germany. EM csavigny@iup.physik.uni-bremen.de RI Kaiser, Johannes/A-7057-2012; von Savigny, Christian/B-3910-2014; Bovensmann, Heinrich/P-4135-2016; OI Kaiser, Johannes/0000-0003-3696-9123; Bovensmann, Heinrich/0000-0001-8882-4108; Burrows, John Philip/0000-0002-6821-5580 NR 33 TC 39 Z9 39 U1 0 U2 0 PU EUROPEAN GEOSCIENCES UNION PI KATLENBURG-LINDAU PA MAX-PLANCK-STR 13, 37191 KATLENBURG-LINDAU, GERMANY SN 1680-7324 J9 ATMOS CHEM PHYS JI Atmos. Chem. Phys. PD SEP 29 PY 2005 VL 5 BP 2593 EP 2602 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 969AG UT WOS:000232205200001 ER PT J AU Hashimoto, K Anderson, RR Green, JL Matsumoto, H AF Hashimoto, K Anderson, RR Green, JL Matsumoto, H TI Source and propagation characteristics of kilometric continuum observed with multiple satellites SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID TERRESTRIAL MYRIAMETRIC RADIATION; GEOTAIL; PLASMAPAUSE; SPACECRAFT; IMAGER AB [ 1] Kilometric continuum radiation is the high-frequency extension of escaping continuum emissions in the frequency range from 100 to 800 kHz. It was first identified with the Geotail Plasma Wave Instrument (PWI) and has been observed with various satellites. Previous results from the IMAGE Radio Plasma Imager and extreme ultraviolet experiments show that kilometric continuum is generated at the plasmapause, in or near the magnetic equator, within a notch region. In this study, data from the CRRES PWI have also identified other new sources of kilometric continuum from equatorial density irregularities inside the plasmasphere as well as at the plasmapause. An example of CRRES observations reveals that kilometric continuum can be radiated into a wide-beam emission contrary to the beaming theory. IMAGE and Geotail simultaneous kilometric continuum observations measure a very broad emission cone of up to about +/- 30 degrees. C1 Kyoto Univ, Res Inst Sustainable Humanosphere, Kyoto 6110011, Japan. Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Hashimoto, K (reprint author), Kyoto Univ, Res Inst Sustainable Humanosphere, Kyoto 6110011, Japan. EM kozo@rish.kyoto-u.ac.jp 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 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD SEP 29 PY 2005 VL 110 IS A9 AR A09229 DI 10.1029/2004JA010729 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 973HB UT WOS:000232512400001 ER PT J AU Morris, GA Bojkov, BR Lait, LR Schoeberl, MR AF Morris, GA Bojkov, BR Lait, LR Schoeberl, MR TI A review of the Match technique as applied to AASE-2/EASOE and SOLVE/THESEO 2000 SO ATMOSPHERIC CHEMISTRY AND PHYSICS LA English DT Article ID CHEMICAL OZONE LOSS; STRATOSPHERIC ARCTIC VORTEX; TRACE GAS OBSERVATIONS; IN-SITU OBSERVATIONS; POLAR VORTEX; POTENTIAL VORTICITY; LOSS RATES; CHLORINE ACTIVATION; WINTER; DEPLETION AB We apply the NASA Goddard Trajectory Model to data from a series of ozonesondes to derive ozone loss rates in the lower stratosphere for the AASE-2/EASOE mission (January-March 1992) and for the SOLVE/THESEO 2000 mission (January-March 2000) in an approach similar to Match. Ozone loss rates are computed by comparing the ozone concentrations provided by ozonesondes launched at the beginning and end of the trajectories connecting the launches. We investigate the sensitivity of the Match results to the various parameters used to reject potential matches in the original Match technique. While these filters effectively eliminate from consideration 80% of the matched sonde pairs and >99% of matched observations in our study, we conclude that only a filter based on potential vorticity changes along the calculated back trajectories seems warranted. Our study also demonstrates that the ozone loss rates estimated in Match can vary by up to a factor of two depending upon the precise trajectory paths calculated for each trajectory. As a result, the statistical uncertainties published with previous Match results might need to be augmented by an additional systematic error. The sensitivity to the trajectory path is particularly pronounced in the month of January, for which the largest ozone loss rate discrepancies between photochemical models and Match are found. For most of the two study periods, our ozone loss rates agree with those previously published. Notable exceptions are found for January 1992 at 475 K and late February/early March 2000 at 450 K, both periods during which we generally find smaller loss rates than the previous Match studies. Integrated ozone loss rates estimated by Match in both of those years compare well with those found in numerous other studies and in a potential vorticity/potential temperature approach shown previously and in this paper. Finally, we suggest an alternate approach to Match using trajectory mapping. This approach uses information from all matched observations without filtering and uses a two-parameter fit to the data to produce robust ozone loss rate estimates. As compared to loss rates from our version of Match, the trajectory mapping approach produces generally smaller loss rates, frequently not statistically significantly different from zero, calling into question the efficacy of the Match approach. C1 Rice Univ, Dept Phys & Astron, Houston, TX 77251 USA. Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA. NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. RP Morris, GA (reprint author), Valparaiso Univ, Dept Phys & Astron, Valparaiso, IN 46383 USA. EM gary.morris@valpo.edu NR 69 TC 6 Z9 6 U1 0 U2 1 PU COPERNICUS GESELLSCHAFT MBH PI GOTTINGEN PA BAHNHOFSALLEE 1E, GOTTINGEN, 37081, GERMANY SN 1680-7316 J9 ATMOS CHEM PHYS JI Atmos. Chem. Phys. PD SEP 28 PY 2005 VL 5 BP 2571 EP 2592 PG 22 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 968MK UT WOS:000232166400001 ER PT J AU Spinhirne, JD Palm, SP Hart, WD Hlavka, DL Welton, EJ AF Spinhirne, JD Palm, SP Hart, WD Hlavka, DL Welton, EJ TI Cloud and aerosol measurements from GLAS: Overview and initial results SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID OCEAN AB Global space borne lidar profiling of atmospheric clouds and aerosol began in 2003 following the launch of the Geoscience Laser Altimeter System (GLAS) on the Ice, Cloud and land Elevation Satellite. GLAS obtains nadir profiles through the atmosphere in two wavelength channels, day and night, at a fundamental resolution of 76.8 m vertical and 172 m along track. The 532 nm channel uses photon-counting detectors and resolves profiles of observed backscatter cross sections to 10(-7) 1/m-sr. The 1064 nm channel employs analog detection adequate to 10(-6) 1/m-sr and with greater dynamic range. By 2005 approximately seven months of global data are available. Processing algorithms produce data products for the corrected lidar signal, cloud and aerosol layer boundaries and optical thickness and extinction and backscatter cross sections. Operational sensitivity is shown by the frequency distribution for cloud optical thickness peaking at approximately 0.02. C1 NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA. Sci Syst & Applicat Inc, Lanham, MD 20706 USA. RP Spinhirne, JD (reprint author), NASA, Goddard Space Flight Ctr, Atmospheres Lab, Code 613-1, Greenbelt, MD 20771 USA. EM jspin@virl.gsfc.nasa.gov RI Welton, Ellsworth/A-8362-2012 NR 11 TC 52 Z9 55 U1 1 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 SEP 28 PY 2005 VL 32 IS 22 AR L22S03 DI 10.1029/2005GL023507 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 971PG UT WOS:000232395800001 ER PT J AU Hansen, J Sato, M Ruedy, R Nazarenko, L Lacis, A Schmidt, GA Russell, G Aleinov, I Bauer, M Bauer, S Bell, N Cairns, B Canuto, V Chandler, M Cheng, Y Del Genio, A Faluvegi, G Fleming, E Friend, A Hall, T Jackman, C Kelley, M Kiang, N Koch, D Lean, J Lerner, J Lo, K Menon, S Miller, R Minnis, P Novakov, T Oinas, V Perlwitz, J Perlwitz, J Rind, D Romanou, A Shindell, D Stone, P Sun, S Tausnev, N Thresher, D Wielicki, B Wong, T Yao, M Zhang, S AF Hansen, J Sato, M Ruedy, R Nazarenko, L Lacis, A Schmidt, GA Russell, G Aleinov, I Bauer, M Bauer, S Bell, N Cairns, B Canuto, V Chandler, M Cheng, Y Del Genio, A Faluvegi, G Fleming, E Friend, A Hall, T Jackman, C Kelley, M Kiang, N Koch, D Lean, J Lerner, J Lo, K Menon, S Miller, R Minnis, P Novakov, T Oinas, V Perlwitz, J Perlwitz, J Rind, D Romanou, A Shindell, D Stone, P Sun, S Tausnev, N Thresher, D Wielicki, B Wong, T Yao, M Zhang, S TI Efficacy of climate forcings SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Review ID GENERAL-CIRCULATION MODEL; STRATOSPHERIC WATER-VAPOR; LAND-COVER CHANGE; BLACK CARBON; GREENHOUSE-GAS; OZONE CHANGES; TROPOSPHERIC OZONE; RADIATIVE FORCINGS; SEA-ICE; MARINE STRATOCUMULUS AB [1] We use a global climate model to compare the effectiveness of many climate forcing agents for producing climate change. We find a substantial range in the "efficacy'' of different forcings, where the efficacy is the global temperature response per unit forcing relative to the response to CO2 forcing. Anthropogenic CH4 has efficacy similar to 110%, which increases to similar to 145% when its indirect effects on stratospheric H2O and tropospheric O-3 are included, yielding an effective climate forcing of similar to 0.8 W/m(2) for the period 1750 - 2000 and making CH4 the largest anthropogenic climate forcing other than CO2. Black carbon (BC) aerosols from biomass burning have a calculated efficacy similar to 58%, while fossil fuel BC has an efficacy similar to 78%. Accounting for forcing efficacies and for indirect effects via snow albedo and cloud changes, we find that fossil fuel soot, defined as BC + OC ( organic carbon), has a net positive forcing while biomass burning BC + OC has a negative forcing. We show that replacement of the traditional instantaneous and adjusted forcings, Fi and Fa, with an easily computed alternative, Fs, yields a better predictor of climate change, i.e., its efficacies are closer to unity. Fs is inferred from flux and temperature changes in a fixed-ocean model run. There is remarkable congruence in the spatial distribution of climate change, normalized to the same forcing Fs, for most climate forcing agents, suggesting that the global forcing has more relevance to regional climate change than may have been anticipated. Increasing greenhouse gases intensify the Hadley circulation in our model, increasing rainfall in the Intertropical Convergence Zone (ITCZ), Eastern United States, and East Asia, while intensifying dry conditions in the subtropics including the Southwest United States, the Mediterranean region, the Middle East, and an expanding Sahel. These features survive in model simulations that use all estimated forcings for the period 1880 - 2000. Responses to localized forcings, such as land use change and heavy regional concentrations of BC aerosols, include more specific regional characteristics. We suggest that anthropogenic tropospheric O-3 and the BC snow albedo effect contribute substantially to rapid warming and sea ice loss in the Arctic. As a complement to a priori forcings, such as Fi, Fa, and Fs, we tabulate the a posteriori effective forcing, Fe, which is the product of the forcing and its efficacy. Fe requires calculation of the climate response and introduces greater model dependence, but once it is calculated for a given amount of a forcing agent it provides a good prediction of the response to other forcing amounts. C1 NASA, Goddard Inst Space Studies, New York, NY 10025 USA. Columbia Univ, Earth Inst, New York, NY 10025 USA. SGT Inc, New York, NY 10025 USA. Columbia Univ, Dept Earth & Environm Sci, New York, NY 10025 USA. Columbia Univ, Dept Appl Phys & Appl Math, New York, NY 10025 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Orme Merisiers, Lab Sci Climat & Environm, F-91198 Gif Sur Yvette, France. Yale Univ, Dept Geol, New Haven, CT USA. USN, Res Lab, Washington, DC 20375 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. MIT, Ctr Meteorol, Cambridge, MA 02139 USA. RP NASA, Goddard Inst Space Studies, New York, NY 10025 USA. EM jhansen@giss.nasa.gov RI Lacis, Andrew/D-4658-2012; Jackman, Charles/D-4699-2012; Minnis, Patrick/G-1902-2010; Unger, Nadine/M-9360-2015; Shindell, Drew/D-4636-2012; Schmidt, Gavin/D-4427-2012; Del Genio, Anthony/D-4663-2012; Perlwitz, Judith/B-7201-2008; Miller, Ron/E-1902-2012; LU, C/C-6598-2008 OI Minnis, Patrick/0000-0002-4733-6148; Schmidt, Gavin/0000-0002-2258-0486; Del Genio, Anthony/0000-0001-7450-1359; Perlwitz, Judith/0000-0003-4061-2442; NR 174 TC 695 Z9 706 U1 18 U2 50 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 SEP 28 PY 2005 VL 110 IS D18 AR D18104 DI 10.1029/2005JD005776 PG 45 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 971PP UT WOS:000232396700004 ER PT J AU Farrell, WM Desch, MD Kaiser, ML Lecacheux, A Kurth, WS Gurnett, DA Cecconi, B Zarka, P AF Farrell, WM Desch, MD Kaiser, ML Lecacheux, A Kurth, WS Gurnett, DA Cecconi, B Zarka, P TI A nightside source of Saturn's kilometric radiation: Evidence for an inner magnetosphere energy driver SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID RADIO-EMISSION; EARTH AB During Cassini's orbit insertion about Saturn, the spacecraft passed within 1.4 R-s of the planet passing from dayside into the nightside region. During this nightside passage, the onboard Radio and Plasma Wave (RPWS) instrument surprisingly detected Saturn kilometric radiation (SKR). Prior to this encounter, it was believed that SKR originated from a high-latitude dayside source, and radio beams from such a source would not be viewable in this nearplanet night-side location. Subsequent analysis presented here reveals that this SKR did indeed originate from the near-midnight region on field lines near L similar to 10 - 15. Such a radio source suggests the presence of an active region in the night-side inner magnetosphere; this source possibly being near the outer edge of the icy-moon created plasma torus surrounding the planet. The implication is that some of the SKR is driven by an internal energy source that may also account for recent UV aurora observations. C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Observ Paris, F-92195 Meudon, France. Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA. RP Farrell, WM (reprint author), NASA, Goddard Space Flight Ctr, Mail Code 695, Greenbelt, MD 20771 USA. EM william.farrell@gsfc.nasa.gov RI Farrell, William/I-4865-2013 NR 19 TC 1 Z9 1 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 SEP 27 PY 2005 VL 32 IS 18 AR L18107 DI 10.1029/2005GL023449 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 971OU UT WOS:000232394600002 ER PT J AU Li, JL Waliser, DE Jiang, JH Wu, DL Read, W Waters, JW Tompkins, AM Donner, LJ Chern, JD Tao, WK Atlas, R Gu, Y Liou, KN Del Genio, A Khairoutdinov, M Gettelman, A AF Li, JL Waliser, DE Jiang, JH Wu, DL Read, W Waters, JW Tompkins, AM Donner, LJ Chern, JD Tao, WK Atlas, R Gu, Y Liou, KN Del Genio, A Khairoutdinov, M Gettelman, A TI Comparisons of EOS MLS cloud ice measurements with ECMWF analyses and GCM simulations: Initial results SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID CIRRUS CLOUDS; PARAMETERIZATION; VARIABILITY; FLUXES; CYCLE; MODEL AB To assess the status of global climate models (GCMs) in simulating upper-tropospheric ice water content (IWC), a new set of IWC measurements from the Earth Observing System's Microwave Limb Sounder (MLS) are used. Comparisons are made with ECMWF analyses and simulations from several GCMs, including two with multi-scale-modeling framework. For January 2005 monthly and daily mean values, the spatial agreement between MLS and ECMWF is quite good, although MLS estimates are higher by a factor of 2 - 3 over the Western Pacific, tropical Africa and South America. For the GCMs, the model-data agreement is within a factor of 2 - 4 with larger values of disagreement occurring over Eastern Pacific and Atlantic ITCZs, tropical Africa and South America. The implications arising from sampling and uncertainties in the observations, the modeled values and their comparison are discussed. These initial results demonstrate the potential usefulness of this data set for evaluating GCM performance and guiding development efforts. C1 SkillStorm Jet Prop Lab, Pasadena, CA 91109 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. European Ctr Medium Range Weather Forecasts, Reading RG6 6AL, Berks, England. Geophys Fluid Dynam Lab, Princeton, NJ 08542 USA. NASA, Goddard Earth Sci & Technol Ctr, GSFC, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Calif Los Angeles, Los Angeles, CA 90095 USA. NASA, Goddard Inst Space Studies, New York, NY 10025 USA. Colorado State Univ, Ft Collins, CO 80523 USA. Natl Ctr Atmospher Res, Boulder, CO 80305 USA. RP Li, JL (reprint author), SkillStorm Jet Prop Lab, MS 183-601,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM jli@jpl.nasa.gov RI Atlas, Robert/A-5963-2011; Del Genio, Anthony/D-4663-2012; Tompkins, Adrian/N-6472-2013; Wu, Dong/D-5375-2012 OI Atlas, Robert/0000-0002-0706-3560; Del Genio, Anthony/0000-0001-7450-1359; Tompkins, Adrian/0000-0003-0975-6691; NR 16 TC 49 Z9 49 U1 1 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 SEP 27 PY 2005 VL 32 IS 18 AR L18710 DI 10.1029/2005GL023788 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 971OU UT WOS:000232394600005 ER PT J AU Tsurutani, BT Gonzalez, WD Lakhina, GS Alex, S AF Tsurutani, BT Gonzalez, WD Lakhina, GS Alex, S TI Reply to comment by S.-I. Akasofu and Y. Kamide on "The extreme magnetic storm of 1-2 September 1859" SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Editorial Material ID VISCOUS INTERACTION; RING CURRENT; SOLAR-WIND; MAGNETOSPHERE; PROMINENCE; EFFICIENCY C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Inst Nacl Pesquisas Espaciais, BR-12200 Sao Jose Dos Campos, SP, Brazil. Indian Inst Geomagnetism, Bombay 400005, Maharashtra, India. Kyoto Univ, Res Inst Sustainable Humanosphere, Kyoto, Japan. RP Tsurutani, BT (reprint author), CALTECH, Jet Prop Lab, MS 169-506,4800 Oak Grove Dr, Pasadena, CA 91109 USA. 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