FN Thomson Reuters Web of Science™
VR 1.0
PT J
AU Wong, T
Hughes, A
Fukui, Y
Kawamura, A
Mizuno, N
Ott, J
Muller, E
Pineda, JL
Welty, DE
Kim, S
Mizuno, Y
Murai, M
Onishi, T
AF Wong, T.
Hughes, A.
Fukui, Y.
Kawamura, A.
Mizuno, N.
Ott, J.
Muller, E.
Pineda, J. L.
Welty, D. E.
Kim, S.
Mizuno, Y.
Murai, M.
Onishi, T.
TI MOLECULAR AND ATOMIC GAS IN THE LARGE MAGELLANIC CLOUD. I. CONDITIONS
FOR CO DETECTION
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE galaxies: ISM; ISM: molecules; Magellanic Clouds
ID STAR-FORMATION; H-I; INTERSTELLAR CLOUDS; SPIRAL GALAXIES;
GRAVITATIONAL-INSTABILITY; APERTURE SYNTHESIS; RAPID FORMATION; SPITZER
SURVEY; HYDROGEN; LMC
AB We analyze the conditions for detection of CO(1-0) emission in the Large Magellanic Cloud, using the recently completed second NANTEN CO survey. In particular, we investigate correlations between CO integrated intensity and H I integrated intensity, peak brightness temperature, and line width at a resolution of 2'.6 (similar to 40 pc). We find that significant H I column density (exceeding similar to 10(21) cm(-2)) and peak brightness temperature (exceeding similar to 20 K) are necessary but not sufficient conditions for CO detection, with many regions of strong H I emission not associated with molecular clouds. The large scatter in CO intensities for a given H I intensity persists even when averaging on scales of > 200 pc, indicating that the scatter is not solely due to local conversion of H I into H(2) near GMCs. We focus on two possibilities to account for this scatter: either there exist spatial variations in the I(CO) to N(H(2)) conversion factor, or a significant fraction of the atomic gas is not involved in molecular cloud formation. A weak tendency for CO emission to be suppressed for large H I linewidths supports the second hypothesis, insofar as large linewidths may be indicative of warm H I, and calls into question the likelihood of forming molecular clouds from colliding H I flows. We also find that the ratio of molecular to atomic gas shows no significant correlation (or anticorrelation) with the stellar surface density, though a correlation with midplane hydrostatic pressure P(h) is found when the data are binned in P(h). The latter correlation largely reflects the increasing likelihood of CO detection at high H I column density.
C1 [Wong, T.; Welty, D. E.] Univ Illinois, Dept Astron, Urbana, IL 61801 USA.
[Wong, T.; Hughes, A.; Muller, E.] CSIRO, Australia Telescope Natl Facil, Epping, NSW 1710, Australia.
[Hughes, A.] Swinburne Univ Technol, Ctr Astrophys & Supercomp, Hawthorn, Vic 3122, Australia.
[Fukui, Y.; Kawamura, A.; Mizuno, N.; Muller, E.; Mizuno, Y.; Murai, M.; Onishi, T.] Nagoya Univ, Dept Phys, Chikusa Ku, Nagoya, Aichi 4648602, Japan.
[Mizuno, N.] Natl Astron Observ Japan, ALMA J Project Off, Tokyo 1818588, Japan.
[Ott, J.] Natl Radio Astron Observ, Charlottesville, VA 22903 USA.
[Ott, J.] CALTECH, Caltech Astron, Pasadena, CA 91125 USA.
[Pineda, J. L.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
[Kim, S.] Sejong Univ, Dept Astron & Space Sci, Seoul 143747, South Korea.
RP Wong, T (reprint author), Univ Illinois, Dept Astron, 1002 W Green St, Urbana, IL 61801 USA.
EM wongt@astro.uiuc.edu
FU ATNF; Nagoya University; University of Illinois; NRAO; NASA; Korea
Science and Engineering Foundation (KOSEF); Astrophysical Research
Center of the Structure and Evolution of the Cosmos (ARCSEC)
FX We thank Robert Gruendl for providing the stellar surface density image
and Lister Staveley-Smith for providing the Hi data cube for analysis.
The survival analysis used in this study was performed with the ASURV
software provided by the Penn State Center for Astrostatistics. T.W.
acknowledges support from the ATNF and Nagoya University during the
early stages of this project, and support from the University of
Illinois during its completion. J.O. acknowledges support from NRAO,
which is operated by Associated Universities, Inc., under cooperative
agreement with the National Science Foundation. J.L.P. was supported by
an appointment to the NASA Postdoctoral Program at the Jet Propulsion
Laboratory, administered by Oak Ridge Associated Universities through a
contract with NASA. S.K. was supported in part by the Korea Science and
Engineering Foundation (KOSEF) under a cooperative agreement with the
Astrophysical Research Center of the Structure and Evolution of the
Cosmos (ARCSEC). We thank the referee for a detailed report which led to
significant improvement and clarification of the text and figures.
NR 67
TC 26
Z9 26
U1 0
U2 4
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 MAY 1
PY 2009
VL 696
IS 1
BP 370
EP 384
DI 10.1088/0004-637X/696/1/370
PG 15
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 435NH
UT WOS:000265350100033
ER
PT J
AU Hildebrand, RH
Kirby, L
Dotson, JL
Houde, M
Vaillancourt, JE
AF Hildebrand, Roger H.
Kirby, Larry
Dotson, Jessie L.
Houde, Martin
Vaillancourt, John E.
TI DISPERSION OF MAGNETIC FIELDS IN MOLECULAR CLOUDS. I
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE ISM: clouds; ISM: magnetic fields; polarization; turbulence
ID STAR-FORMING REGIONS; LARGE-SCALE STRUCTURE; POLARIZATION; POLARIMETRY;
TURBULENCE; CORES; FLUCTUATIONS; STRENGTHS; VELOCITY; DENSITY
AB We describe a method for determining the dispersion of magnetic field vectors about large-scale fields in turbulent molecular clouds. The method is designed to avoid inaccurate estimates of magnetohydrodynamic or turbulent dispersion-and help avoiding inaccurate estimates of field strengths-due to a large-scale, nonturbulent field structure when using the well known method of Chandrasekhar and Fermi. Our method also provides accurate, independent estimates of the turbulent to large-scale magnetic field strength ratio. We discuss applications to the molecular clouds OMC-1, M17, and DR21(Main).
C1 [Hildebrand, Roger H.; Kirby, Larry] Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA.
[Hildebrand, Roger H.; Kirby, Larry] Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA.
[Hildebrand, Roger H.] Univ Chicago, Dept Phys, Chicago, IL 60637 USA.
[Dotson, Jessie L.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA.
[Houde, Martin] Univ Western Ontario, Dept Phys & Astron, London, ON N6A 3K7, Canada.
[Vaillancourt, John E.] CALTECH, Div Phys Math & Astron, Pasadena, CA 91125 USA.
RP Hildebrand, RH (reprint author), Univ Chicago, Dept Astron & Astrophys, 5640 S Ellis Ave, Chicago, IL 60637 USA.
FU NSF [AST 05-05230, AST 02-41356, AST 05-05124]; Department of Astronomy;
Astrophysics of the University of Chicago; NSERC; Canada Research Chair;
Canada Foundation for Innovation; Ontario Innovation Trust; Western's
Academic Development Fund; CSO [AST 05-40882]
FX We thank Shantanu Basu for helpful discussions. This work has been
supported in part by NSF grants AST 05-05230, AST 02-41356, and AST
05-05124. L. K. acknowledges support from the Department of Astronomy
and Astrophysics of the University of Chicago. M.H.' s research is
funded through the NSERC Discovery Grant, Canada Research Chair, Canada
Foundation for Innovation, Ontario Innovation Trust, and Western's
Academic Development Fund programs. J.E.V. acknowledges support from the
CSO, which is funded through NSF AST 05-40882.
NR 33
TC 77
Z9 77
U1 0
U2 4
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 MAY 1
PY 2009
VL 696
IS 1
BP 567
EP 573
DI 10.1088/0004-637X/696/1/567
PG 7
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 435NH
UT WOS:000265350100045
ER
PT J
AU Stritzinger, M
Mazzali, P
Phillips, MM
Immler, S
Soderberg, A
Sollerman, J
Boldt, L
Braithwaite, J
Brown, P
Burns, CR
Contreras, C
Covarrubias, R
Folatelli, G
Freedman, WL
Gonzalez, S
Hamuy, M
Krzeminski, W
Madore, BF
Milne, P
Morrell, N
Persson, SE
Roth, M
Smith, M
Suntzeff, NB
AF Stritzinger, Maximilian
Mazzali, Paolo
Phillips, Mark M.
Immler, Stefan
Soderberg, Alicia
Sollerman, Jesper
Boldt, Luis
Braithwaite, Jonathan
Brown, Peter
Burns, Christopher R.
Contreras, Carlos
Covarrubias, Ricardo
Folatelli, Gaston
Freedman, Wendy L.
Gonzalez, Sergio
Hamuy, Mario
Krzeminski, Wojtek
Madore, Barry F.
Milne, Peter
Morrell, Nidia
Persson, S. E.
Roth, Miguel
Smith, Mathew
Suntzeff, Nicholas B.
TI THE HE-RICH CORE-COLLAPSE SUPERNOVA 2007Y: OBSERVATIONS FROM X-RAY TO
RADIO WAVELENGTHS
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE galaxies: individual (NGC 1187); supernovae: general; supernovae:
individual (SN 2007Y)
ID 25 APRIL 1998; IB SUPERNOVA; LIGHT CURVES; CIRCUMSTELLAR INTERACTION;
STANDARD STARS; NEUTRON-STAR; SN 1993J; PHOTOMETRIC CALIBRATION; OPTICAL
SPECTROSCOPY; UBVRI PHOTOMETRY
AB A detailed study spanning approximately a year has been conducted on the Type Ib supernova (SN) 2007Y. Imaging was obtained from X-ray to radio wavelengths, and a comprehensive set of multi-band (w2m2w1u'g'r'i'UBVYJHK(s)) light curves and optical spectroscopy is presented. A virtually complete bolometric light curve is derived, from which we infer a (56)Ni mass of 0.06 M(circle dot). The early spectrum strongly resembles SN 2005bf and exhibits high- velocity features of Ca II and H alpha; during late epochs the spectrum shows evidence of an ejecta-wind interaction. Nebular emission lines have similar widths and exhibit profiles that indicate a lack of major asymmetry in the ejecta. Late phase spectra are modeled with a non-LTE code, from which we find (56)Ni, O, and total-ejecta masses (excluding He) to be 0.06, 0.2, and 0.42 M(circle dot), respectively, below 4500 km s(-1). The (56)Ni mass confirms results obtained from the bolometric light curve. The oxygen abundance suggests that the progenitor was most likely a approximate to 3.3 M(circle dot) He core star that evolved from a zero-age-main-sequence mass of 10-13 M(circle dot). The explosion energy is determined to be approximate to 10(50) erg, and the mass-loss rate of the progenitor is constrained from X-ray and radio observations to be less than or similar to 10(-6) M(circle dot) yr(-1). SN 2007Y is among the least energetic normal Type Ib SNe ever studied.
C1 [Stritzinger, Maximilian; Phillips, Mark M.; Boldt, Luis; Contreras, Carlos; Covarrubias, Ricardo; Gonzalez, Sergio; Krzeminski, Wojtek; Morrell, Nidia; Roth, Miguel] Carnegie Observ, Las Campanas Observ, La Serena, Chile.
[Stritzinger, Maximilian; Sollerman, Jesper] Univ Copenhagen, Dark Cosmol Ctr, Niels Bohr Inst, DK-2100 Copenhagen O, Denmark.
[Mazzali, Paolo] Max Planck Inst Astrophys, D-85741 Garching, Germany.
[Mazzali, Paolo] Osserv Astron Padova, INAF, I-35122 Padua, Italy.
[Immler, Stefan] NASA, Goddard Space Flight Ctr, Astrophys Sci Div, XrayAstrophys Lab, Greenbelt, MD 20771 USA.
[Immler, Stefan] Univ Space Res Assoc, Columbia, MD 21044 USA.
[Soderberg, Alicia] Princeton Univ, Dept Astrophys Sci, Princeton, NJ 08544 USA.
[Soderberg, Alicia] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA.
[Sollerman, Jesper] Stockholm Univ, Dept Astron, SE-10691 Stockholm, Sweden.
[Braithwaite, Jonathan] Canadian Inst Theoret Astrophys, Toronto, ON M5S 3H8, Canada.
[Brown, Peter] Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA.
[Burns, Christopher R.; Freedman, Wendy L.; Madore, Barry F.; Persson, S. E.] Observ Carnegie Inst Washington, Pasadena, CA 91101 USA.
[Folatelli, Gaston; Hamuy, Mario] Univ Chile, Dept Astron, Santiago, Chile.
[Madore, Barry F.] CALTECH, Jet Prop Lab, Ctr Infrared Proc & Anal, Pasadena, CA 91125 USA.
[Milne, Peter] Univ Arizona, Dept Astron & Steward Observ, Tucson, AZ 85721 USA.
[Smith, Mathew] Univ Cape Town, Cosmol & Grav Grp, Dept Math & Appl Math, ZA-7700 Rondebosch, South Africa.
[Suntzeff, Nicholas B.] Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA.
RP Stritzinger, M (reprint author), Carnegie Observ, Las Campanas Observ, Casilla 601, La Serena, Chile.
EM mstritzinger@lco.cl; mazzali@mpa-garching.mpg.de; mmp@lco.cl;
stefan.m.immler@nasa.gov; alicia@astro.princeton.edu;
jesper@dark-cosmology.dk; lboldt@lco.cl; jon@cita.utoronto.ca;
pbrown@astro.psu.edu; cburns@ociw.edu; ccontreras@lco.cl;
ricardo@lco.cl; gaston@das.uchile.cl; wendy@ociw.edu; sgonzalez@lco.cl;
mhamuy@das.uchile.cl; wojtek@lco.cl; barry@ociw.edu;
pmilne@as.asrizona.edu; nmorrell@lco.cl; persson@ociw.edu;
miguel@lco.cl; mathew.smith@uct.ac.za; nsuntzeff@tamu.edu
RI Folatelli, Gaston/A-4484-2011; Hamuy, Mario/G-7541-2016;
OI Sollerman, Jesper/0000-0003-1546-6615; stritzinger,
maximilian/0000-0002-5571-1833
NR 97
TC 54
Z9 54
U1 0
U2 3
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 MAY 1
PY 2009
VL 696
IS 1
BP 713
EP 728
DI 10.1088/0004-637X/696/1/713
PG 16
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 435NH
UT WOS:000265350100061
ER
PT J
AU Patsourakos, S
Klimchuk, JA
AF Patsourakos, S.
Klimchuk, J. A.
TI SPECTROSCOPIC OBSERVATIONS OF HOT LINES CONSTRAINING CORONAL HEATING IN
SOLAR ACTIVE REGIONS
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE Sun: corona
ID EUV IMAGING SPECTROMETER; X-RAY; EMISSION-LINES; LOOP OBSERVATIONS;
ATOMIC DATABASE; HINODE; PLASMA; DIAGNOSTICS; FIELD; TEMPERATURE
AB Extreme-ultraviolet observations of warm coronal loops suggest that they are bundles of unresolved strands that are heated impulsively to high temperatures by nanoflares. The plasma would then have the observed properties ( e. g., excess density compared with static equilibrium) when it cools into the 1-2MK range. If this interpretation is correct, then very hot emission should be present outside of proper flares. It is predicted to be very faint, however. A critical element for proving or refuting this hypothesis is the existence of hot, yet faint plasmas which should be at amounts predicted by impulsive heating models. We report on the first comprehensive spectroscopic study of hot plasmas in active regions (ARs). Data from the Extreme- ultraviolet Imaging Spectrometer on Hinode were used to construct emission measure (EM) distributions in quiescent ARs in the 1-5MK temperature range. The distributions are flat or slowly increasing up to approximately 3MK and then fall off rapidly at higher temperatures. We show that AR models based on impulsive heating can reproduce the observed EM distributions relatively well. Our results provide strong new evidence that coronal heating is impulsive in nature.
C1 [Patsourakos, S.] USN, Res Lab, Div Space Sci, Washington, DC 20375 USA.
[Patsourakos, S.] George Mason Univ, Ctr Earth Observing & Space Res, Inst Computat Sci, Coll Sci, Fairfax, VA 22030 USA.
[Klimchuk, J. A.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
RP Patsourakos, S (reprint author), USN, Res Lab, Div Space Sci, Washington, DC 20375 USA.
RI Klimchuk, James/D-1041-2012
OI Klimchuk, James/0000-0003-2255-0305
FU NASA Hinode and LWS programs
FX Hinode is a Japanese mission developed and launched by ISAS/JAXA, with
NAOJ as domestic partner and NASA and STFC (UK) as international
partners. It is operated by these agencies in cooperation with ESA and
NSC ( Norway). This work was supported by the NASA Hinode and LWS
programs. We wish to thank H. Warren, I. Ugarte Urra, U. Feldman, C.
Brown, E. Robbrecht, G. Doscheck J.-F. Hochedez, and J. Mariska for
helpful discussions. We acknowledge useful discussions with the members
of the ISSI team "The Role of Spectroscopic and Imaging Data in
Understanding Coronal Heating" ( team Parenti).
NR 41
TC 31
Z9 31
U1 0
U2 2
PU IOP PUBLISHING LTD
PI BRISTOL
PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND
SN 0004-637X
EI 1538-4357
J9 ASTROPHYS J
JI Astrophys. J.
PD MAY 1
PY 2009
VL 696
IS 1
BP 760
EP 765
DI 10.1088/0004-637X/696/1/760
PG 6
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 435NH
UT WOS:000265350100065
ER
PT J
AU Hickox, RC
Jones, C
Forman, WR
Murray, SS
Kochanek, CS
Eisenstein, D
Jannuzi, BT
Dey, A
Brown, MJI
Stern, D
Eisenhardt, PR
Gorjian, V
Brodwin, M
Narayan, R
Cool, RJ
Kenter, A
Caldwell, N
Anderson, ME
AF Hickox, Ryan C.
Jones, Christine
Forman, William R.
Murray, Stephen S.
Kochanek, Christopher S.
Eisenstein, Daniel
Jannuzi, Buell T.
Dey, Arjun
Brown, Michael J. I.
Stern, Daniel
Eisenhardt, Peter R.
Gorjian, Varoujan
Brodwin, Mark
Narayan, Ramesh
Cool, Richard J.
Kenter, Almus
Caldwell, Nelson
Anderson, Michael E.
TI HOST GALAXIES, CLUSTERING, EDDINGTON RATIOS, AND EVOLUTION OF RADIO,
X-RAY, AND INFRARED-SELECTED AGNs
SO ASTROPHYSICAL JOURNAL
LA English
DT Review
DE galaxies: active; large-scale structure of universe; quasars: general;
radio continuum: galaxies; surveys; X-rays: galaxies
ID ACTIVE GALACTIC NUCLEI; DIGITAL SKY SURVEY; SUPERMASSIVE BLACK-HOLES;
DEEP FIELD-SOUTH; QUASAR LUMINOSITY FUNCTION; STAR-FORMATION HISTORY;
DARK-MATTER HALOES; ADVECTION-DOMINATED ACCRETION; COLOR-MAGNITUDE
RELATION; IRAC SHALLOW SURVEY
AB We explore the connection between different classes of active galactic nuclei (AGNs) and the evolution of their host galaxies, by deriving host galaxy properties, clustering, and Eddington ratios of AGNs selected in the radio, Xray, and infrared (IR) wavebands. We study a sample of 585 AGNs at 0.25 < z < 0.8 using redshifts from the AGN and Galaxy Evolution Survey ( AGES). We select AGNs with observations in the radio at 1.4 GHz from the Westerbork Synthesis Radio Telescope, X-rays from the Chandra XBootes Survey, and mid-IR from the Spitzer IRAC Shallow Survey. The radio, X-ray, and IR AGN samples show only modest overlap, indicating that to the flux limits of the survey, they represent largely distinct classes of AGNs. We derive host galaxy colors and luminosities, as well as Eddington ratios, for obscured or optically faint AGNs. We also measure the two-point cross-correlation between AGNs and galaxies on scales of 0.3-10 h(-1) Mpc, and derive typical dark matter halo masses. We find that: (1) radio AGNs are mainly found in luminous red sequence galaxies, are strongly clustered (with M(halo) similar to 3 x 10(13) h(-1) M(circle dot)), and have very low Eddington ratios lambda less than or similar to 10(-3); (2) X-ray-selected AGNs are preferentially found in galaxies that lie in the "green valley" of color-magnitude space and are clustered similar to the typical AGES galaxies (M(halo) similar to 10(13) h(-1) M(circle dot)), with 10(-3) less than or similar to lambda less than or similar to 1; (3) IR AGNs reside in slightly bluer, slightly less luminous galaxies than X-ray AGNs, are weakly clustered (M(halo) less than or similar to 10(12)h(-1) M(circle dot)), and have lambda > 10(-2). We interpret these results in terms of a simple model of AGN and galaxy evolution, whereby a "quasar" phase and the growth of the stellar bulge occurs when a galaxy's dark matter halo reaches a critical mass between similar to 10(12) and 10(13) M(circle dot). After this event, star formation ceases and AGN accretion shifts from radiatively efficient (optical- and IR-bright) to radiatively inefficient ( optically faint, radio-bright) modes.
C1 [Hickox, Ryan C.; Jones, Christine; Forman, William R.; Murray, Stephen S.; Brodwin, Mark; Narayan, Ramesh; Kenter, Almus; Caldwell, Nelson; Anderson, Michael E.] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA.
[Kochanek, Christopher S.] Ohio State Univ, Dept Astron, Columbus, OH 43210 USA.
[Kochanek, Christopher S.] Ohio State Univ, Ctr Cosmol & Astroparticle Phys, Columbus, OH 43210 USA.
[Eisenstein, Daniel] Steward Observ, Tucson, AZ 85721 USA.
[Jannuzi, Buell T.; Dey, Arjun; Brodwin, Mark] Natl Opt Astron Observ, Tucson, AZ 85726 USA.
[Brown, Michael J. I.] Monash Univ, Sch Phys, Clayton, Vic 3800, Australia.
[Stern, Daniel; Eisenhardt, Peter R.; Gorjian, Varoujan] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
[Cool, Richard J.] Princeton Univ Observ, Princeton, NJ 08544 USA.
[Anderson, Michael E.] CALTECH, Dept Astron, Pasadena, CA 91109 USA.
RP Hickox, RC (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA.
EM rhickox@cfa.harvard.edu
RI Brown, Michael/B-1181-2015;
OI Brown, Michael/0000-0002-1207-9137; Narayan, Ramesh/0000-0002-1919-2730
NR 209
TC 227
Z9 227
U1 0
U2 3
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 MAY 1
PY 2009
VL 696
IS 1
BP 891
EP 919
DI 10.1088/0004-637X/696/1/891
PG 29
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 435NH
UT WOS:000265350100075
ER
PT J
AU Cieza, LA
Padgett, DL
Allen, LE
McCabe, CE
Brooke, TY
Carey, SJ
Chapman, NL
Fukagawa, M
Huard, TL
Noriga-Crespo, A
Peterson, DE
Rebull, LM
AF Cieza, Lucas A.
Padgett, Deborah L.
Allen, Lori E.
McCabe, Caer E.
Brooke, Timothy Y.
Carey, Sean J.
Chapman, Nicholas L.
Fukagawa, Misato
Huard, Tracy L.
Noriga-Crespo, Alberto
Peterson, Dawn E.
Rebull, Luisa M.
TI PRIMORDIAL CIRCUMSTELLAR DISKS IN BINARY SYSTEMS: EVIDENCE FOR REDUCED
LIFETIMES
SO ASTROPHYSICAL JOURNAL LETTERS
LA English
DT Article
DE binaries: general; circumstellar matter; infrared: stars; planetary
systems: protoplanetary disks; stars: pre-main sequence
ID T-TAURI STARS; GIANT PLANET FORMATION; SPITZER C2D SURVEY; FORMING
REGIONS; YOUNG STARS; PROTOPLANETARY DISKS; CORONAE-AUSTRALIS; IMAGING
SURVEY; CHAMELEON-I; MULTIPLICITY
AB We combine the results from several multiplicity surveys of pre-main-sequence stars located in four nearby star-forming regions with Spitzer data from three different Legacy Projects. This allows us to construct a sample of 349 targets, including 125 binaries, which we use to to investigate the effect of companions on the evolution of circumstellar disks. We find that the distribution of projected separations of systems with Spitzer excesses is significantly different (P similar to 2.4e-5, according to the K-S test for binaries with separations less than 400AU) from that of systems lacking evidence for a disk. As expected, systems with projected separations less than 40AU are half as likely to retain at least one disk than are systems with projected separations in the 40-400 AU range. These results represent the first statistically significant evidence for a correlation between binary separation and the presence of an inner disk (r similar to 1AU). Several factors (e. g., the incompleteness of the census of close binaries, the use of unresolved disk indicators, and projection effects) have previously masked this correlation in smaller samples. We discuss the implications of our findings for circumstellar disk lifetimes and the formation of planets in multiple systems.
C1 [Cieza, Lucas A.] Univ Hawaii Manoa, Inst Astron, Honolulu, HI 96822 USA.
[Padgett, Deborah L.; McCabe, Caer E.; Brooke, Timothy Y.; Carey, Sean J.; Noriga-Crespo, Alberto; Rebull, Luisa M.] CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA.
[Allen, Lori E.; Peterson, Dawn E.] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA.
[Chapman, Nicholas L.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
[Fukagawa, Misato] Osaka Univ, Osaka 5600043, Japan.
[Huard, Tracy L.] Univ Maryland, Dept Astron, College Pk, MD 20742 USA.
RP Cieza, LA (reprint author), Univ Hawaii Manoa, Inst Astron, Honolulu, HI 96822 USA.
EM lcieza@ifa.hawaii.edu
OI Rebull, Luisa/0000-0001-6381-515X
FU NASA through the Spitzer Fellowship Program
FX We thank Jonathan Williams, Jonathan Swift, Michael Liu, and the
anonymous referee for their valuable comments. Support for this work was
provided by NASA through the Spitzer Fellowship Program under an award
from Caltech. This work makes use of data obtained with the Spitzer
Space Telescope, which is operated by JPL/Caltech, under a contract with
NASA.
NR 45
TC 63
Z9 63
U1 0
U2 1
PU IOP PUBLISHING LTD
PI BRISTOL
PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND
J9 ASTROPHYS J LETT
JI Astrophys. J. Lett.
PD MAY 1
PY 2009
VL 696
IS 1
BP L84
EP L88
DI 10.1088/0004-637X/696/1/L84
PG 5
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 434CP
UT WOS:000265253100020
ER
PT J
AU Kovalev, YY
Aller, HD
Aller, MF
Homan, DC
Kadler, M
Kellermann, KI
Kovalev, YA
Lister, ML
McCormick, MJ
Pushkarev, AB
Ros, E
Zensus, JA
AF Kovalev, Y. Y.
Aller, H. D.
Aller, M. F.
Homan, D. C.
Kadler, M.
Kellermann, K. I.
Kovalev, Yu. A.
Lister, M. L.
McCormick, M. J.
Pushkarev, A. B.
Ros, E.
Zensus, J. A.
TI THE RELATION BETWEEN AGN GAMMA-RAY EMISSION AND PARSEC-SCALE RADIO JETS
SO ASTROPHYSICAL JOURNAL LETTERS
LA English
DT Article
DE galaxies: active; galaxies: jets; radio continuum: galaxies
ID ACTIVE GALACTIC NUCLEI; BLAZARS; QUASARS; OBJECTS; MOJAVE; IMAGES; MODEL
AB We have compared the radio emission from a sample of parsec-scale active galactic nucleus (AGN) jets as measured by the VLBA at 15 GHz, with their associated. gamma-ray properties that are reported in the Fermi Large Area Telescope (LAT) three month bright source list. We find in our radio-selected sample that the. gamma-ray photon flux correlates well with the quasi-simultaneously measured compact radio flux density. The LAT-detected jets in our radio-selected complete sample generally have higher compact radio flux densities, and their parsec-scale cores are brighter (i.e., have higher brightness temperature) than the jets in the LAT nondetected objects. This suggests that the jets of bright. gamma-ray AGN have preferentially higher Doppler-boosting factors. In addition, AGN jets tend to be found in a more active radio state within several months from LAT-detection of their strong. gamma-ray emission. This result becomes more pronounced for confirmed. gamma-ray flaring sources. We identify the parsec-scale radio core as a likely location for both the. gamma-ray and radio flares, which appear within typical timescales of up to a few months of each other.
C1 [Kovalev, Y. Y.; Pushkarev, A. B.; Ros, E.; Zensus, J. A.] Max Planck Inst Radioastron, D-53121 Bonn, Germany.
[Kovalev, Y. Y.; Kovalev, Yu. A.] PN Lebedev Phys Inst, Ctr Astro Space, Moscow 117997, Russia.
[Aller, H. D.; Aller, M. F.] Univ Michigan, Dept Astron, Ann Arbor, MI 48109 USA.
[Homan, D. C.; McCormick, M. J.] Denison Univ, Dept Phys & Astron, Granville, OH 43023 USA.
[Kadler, M.] Univ Erlangen Nurnberg, Dr Remeis Sternwarte Bamberg, D-96049 Bamberg, Germany.
[Kadler, M.] Erlangen Ctr Astroparticle Phys, D-91058 Erlangen, Germany.
[Kadler, M.] NASA, Goddard Space Flight Ctr, CRESST, Greenbelt, MD 20771 USA.
[Kadler, M.] Univ Space Res Assoc, Columbia, MD 21044 USA.
[Kellermann, K. I.; Zensus, J. A.] Natl Radio Astron Observ, Charlottesville, VA 22903 USA.
[Lister, M. L.] Purdue Univ, Dept Phys, W Lafayette, IN 47907 USA.
[Pushkarev, A. B.] Pulkovo Observ, St Petersburg 196140, Russia.
[Pushkarev, A. B.] Crimean Astrophys Observ, UA-98409 Nauchnyi, Crimea, Ukraine.
[Ros, E.] Univ Valencia, Dept Astron & Astrofis, E-46100 Valencia, Spain.
RP Kovalev, YY (reprint author), Max Planck Inst Radioastron, Hugel 69, D-53121 Bonn, Germany.
EM ykovalev@mpifr.de; haller@umich.edu; mfa@umich.edu; homand@denison.edu;
matthias.kadler@sternwarte.uni-erlangen.de; kkellerm@nrao.edu;
mlister@purdue.edu; mccorm_m@denison.edu; apushkar@mpifr.de;
ros@mpifr.de; azensus@mpifr.de
RI Kovalev, Yuri/J-5671-2013; Kovalev, Yuri/N-1053-2015; Pushkarev,
Alexander/M-9997-2015;
OI Kovalev, Yuri/0000-0001-9303-3263; Ros, Eduardo/0000-0001-9503-4892;
Kadler, Matthias/0000-0001-5606-6154
NR 28
TC 101
Z9 102
U1 1
U2 4
PU IOP PUBLISHING LTD
PI BRISTOL
PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND
J9 ASTROPHYS J LETT
JI Astrophys. J. Lett.
PD MAY 1
PY 2009
VL 696
IS 1
BP L17
EP L21
DI 10.1088/0004-637X/696/1/L17
PG 5
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 434CP
UT WOS:000265253100005
ER
PT J
AU Lister, ML
Homan, DC
Kadler, M
Kellermann, KI
Kovalev, YY
Ros, E
Savolainen, T
Zensus, JA
AF Lister, M. L.
Homan, D. C.
Kadler, M.
Kellermann, K. I.
Kovalev, Y. Y.
Ros, E.
Savolainen, T.
Zensus, J. A.
TI A CONNECTION BETWEEN APPARENT VLBA JET SPEEDS AND INITIAL ACTIVE
GALACTIC NUCLEUS DETECTIONS MADE BY THE FERMI GAMMA-RAY OBSERVATORY
SO ASTROPHYSICAL JOURNAL LETTERS
LA English
DT Article
DE BL Lacertae objects: general; galaxies: active; galaxies: jets; gamma
rays: observations; quasars: general; radio continuum: galaxies
ID LINE ARRAY OBSERVATIONS; FLUX-LIMITED SAMPLES; BL LACERTAE OBJECTS;
EGRET CATALOG; QUASARS; BLAZARS; VARIABILITY; MULTIEPOCH; MOJAVE; IMAGES
AB In its first three months of operations, the Fermi Gamma-Ray Observatory has detected approximately one quarter of the radio-flux-limited MOJAVE sample of bright flat-spectrum active galactic nuclei (AGNs) at energies above 100 MeV. We have investigated the apparent parsec-scale jet speeds of 26 MOJAVE AGNs measured by the Very Long Baseline Array (VLBA) that are in the LAT bright AGN sample ( LBAS). We find that the. gamma-ray bright quasars have faster jets on average than the non-LBAS quasars, with a median of 15c, and values ranging up to 34c. The LBAS AGNs in which the LAT has detected significant. gamma-ray flux variability generally have faster jets than the nonvariable ones. These findings are in overall agreement with earlier results based on nonuniform EGRET data which suggested that. gamma-ray bright AGNs have preferentially higher Doppler boosting factors than other blazar jets. However, the relatively low LAT detection rates for the full MOJAVE sample (24%) and previously known MOJAVE EGRET-detected blazars (43%) imply that Doppler boosting is not the sole factor that determines whether a particular AGN is bright at. gamma-ray energies. The slower apparent jet speeds of LBAS BL Lac objects and their higher overall LAT detection rate as compared to quasars suggest that the former are being detected by Fermi because of their higher intrinsic (unbeamed). gamma-ray to radio luminosity ratios.
C1 [Lister, M. L.] Purdue Univ, Dept Phys, W Lafayette, IN 47907 USA.
[Homan, D. C.] Denison Univ, Dept Phys & Astron, Granville, OH 43023 USA.
[Kadler, M.] Univ Erlangen Nurnberg, Dr Remeis Sternwarte Bamberg, D-96049 Bamberg, Germany.
[Kadler, M.] Erlangen Ctr Astroparticle Phys, D-91058 Erlangen, Germany.
[Kadler, M.] NASA, Goddard Space Flight Ctr, CRESST, Greenbelt, MD 20771 USA.
[Kadler, M.] Univ Space Res Assoc, Columbia, MD 21044 USA.
[Kellermann, K. I.; Zensus, J. A.] Natl Radio Astron Observ, Charlottesville, VA 22903 USA.
[Kovalev, Y. Y.; Ros, E.; Savolainen, T.; Zensus, J. A.] Max Planck Inst Radioastron, D-53121 Bonn, Germany.
[Kovalev, Y. Y.] PN Lebedev Phys Inst, Ctr Astro Space, Moscow 117997, Russia.
[Ros, E.] Univ Valencia, Dept Astron & Astrofis, E-46100 Valencia, Spain.
RP Lister, ML (reprint author), Purdue Univ, Dept Phys, 525 NW Ave, W Lafayette, IN 47907 USA.
EM mlister@purdue.edu; homand@denison.edu;
matthias.kadler@sternwarte.uni-erlangen.de; kkellerm@nrao.edu;
ykovalev@mpifr.de; ros@mpifr.de; tsavolainen@mpifr.de; azensus@mpifr.de
RI Kovalev, Yuri/J-5671-2013;
OI Kovalev, Yuri/0000-0001-9303-3263; Ros, Eduardo/0000-0001-9503-4892;
Savolainen, Tuomas/0000-0001-6214-1085; Kadler,
Matthias/0000-0001-5606-6154
NR 24
TC 65
Z9 66
U1 1
U2 3
PU IOP PUBLISHING LTD
PI BRISTOL
PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND
J9 ASTROPHYS J LETT
JI Astrophys. J. Lett.
PD MAY 1
PY 2009
VL 696
IS 1
BP L22
EP L26
DI 10.1088/0004-637X/696/1/L22
PG 5
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 434CP
UT WOS:000265253100006
ER
PT J
AU Stothers, RB
AF Stothers, Richard B.
TI ON THE PERIOD AND AMPLITUDE CHANGES IN POLARIS AND OTHER SHORT-PERIOD
CEPHEIDS
SO ASTROPHYSICAL JOURNAL LETTERS
LA English
DT Article
DE stars: interiors; stars: magnetic fields; stars: oscillations; stars:
variables: other; turbulence
ID RR-LYRAE STARS; VARIABLE AMPLITUDE; CONVECTIVE MODEL; PULSATING STARS;
HR-7308; PARALLAXES
AB The observed modulation of the period and amplitude of Polaris, the short-period classical Cepheid, may be cyclical, though irregular, and superimposed on the continuing evolutionary changes of this star. If so, it curiously resembles the Blazhko effect seen in RR Lyrae stars, as Evans and her colleagues have noted. The present author's recent theory of the Blazhko effect based on a solar-like magnetoconvective cycle in the stellar envelope is here applied to Polaris, with some limited success. The theory may also explain the slow cycle seen in another short-period Cepheid, V473 Lyr. It is therefore possible to predict, tentatively, an entire new class of short-period "Blazhko Cepheids."
C1 NASA, Goddard Inst Space Studies, New York, NY 10025 USA.
RP Stothers, RB (reprint author), NASA, Goddard Inst Space Studies, 2880 Broadway, New York, NY 10025 USA.
NR 31
TC 6
Z9 6
U1 0
U2 3
PU IOP PUBLISHING LTD
PI BRISTOL
PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND
J9 ASTROPHYS J LETT
JI Astrophys. J. Lett.
PD MAY 1
PY 2009
VL 696
IS 1
BP L37
EP L39
DI 10.1088/0004-637X/696/1/L37
PG 3
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 434CP
UT WOS:000265253100009
ER
PT J
AU Norbury, JW
AF Norbury, John W.
TI PARAMETERIZATIONS OF INCLUSIVE CROSS SECTIONS FOR KAON, PROTON, AND
ANTIPROTON PRODUCTION IN PROTON-PROTON COLLISIONS
SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
LA English
DT Article
DE elementary particles; methods: analytical; methods: data analysis;
methods: miscellaneous; radiation mechanisms: general
ID GAMMA-RAY EMISSION; SPECTRUM; NUCLEUS; PHYSICS; MODELS
AB Inclusive kaon, proton, and antiproton production from high-energy proton-proton collisions is studied. Various available parameterizations of Lorentz-invariant, differential cross sections, as a function of transverse momentum and rapidity, are compared with experimental data. This paper shows that the Badhwar parameterization provides the best fit for charged kaon production. For proton production, the Alper parameterization is best and for antiproton production the Carey parameterization works best. The formulae for these cross sections are suitable for use in high-energy cosmic ray transport codes.
C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA.
RP Norbury, JW (reprint author), NASA, Langley Res Ctr, Hampton, VA 23681 USA.
EM john.w.norbury@nasa.gov
NR 22
TC 1
Z9 1
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 MAY
PY 2009
VL 182
IS 1
BP 120
EP 126
DI 10.1088/0067-0049/182/1/120
PG 7
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 442BX
UT WOS:000265815900007
ER
PT J
AU Witthoeft, MC
Bautista, MA
Mendoza, C
Kallman, TR
Palmeri, P
Quinet, P
AF Witthoeft, M. C.
Bautista, M. A.
Mendoza, C.
Kallman, T. R.
Palmeri, P.
Quinet, P.
TI K-SHELL PHOTOIONIZATION AND PHOTOABSORPTION OF Ne, Mg, Si, S, Ar, AND Ca
SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
LA English
DT Article
DE atomic data; atomic processes; methods: numerical; X-rays: general
ID R-MATRIX METHOD; GENERAL PROGRAM; VACANCY STATES; ELECTRON-SCATTERING;
CROSS-SECTIONS; AUGER DECAY; ATOMIC DATA; FE-XVII; IONS; IRON
AB We present extensive computations of photoabsorption and photoionization cross sections across the K-edge of Ne, Mg, Si, S, Ar, and Ca ions with less than 11 electrons. The calculations are performed using the Breit-Pauli R-matrix method and include the effects of radiative and Auger damping by means of an optical potential. The wave functions are constructed from single-electron orbital bases obtained using a Thomas-Fermi-Dirac statistical model potential. Configuration interaction is considered among all fine-structure levels within the n = 2 complex. The damping processes affect the resonances converging to the K thresholds causing them to display symmetric profiles of constant width that smear the otherwise sharp edge at the photoionization thresholds.
C1 [Witthoeft, M. C.; Kallman, T. R.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
[Bautista, M. A.] Virginia Polytech & State Univ, Dept Phys, Blacksburg, VA 24061 USA.
[Mendoza, C.] Inst Venezolano Invest Cient, Ctr Fis, Caracas 1020A, Venezuela.
[Palmeri, P.; Quinet, P.] Univ Mons Hainaut, B-7000 Mons, Belgium.
RP Witthoeft, MC (reprint author), NASA, Goddard Space Flight Ctr, Code 662, Greenbelt, MD 20771 USA.
EM bautista@vt.edu
FU NASA Astrophysics Theory Program; FNRS
FX Support for this research was provided in part by a grant from the NASA
Astrophysics Theory Program. M. C. W. is grateful to Nigel Badnell for
many helpful discussions. P. P. and P. Q. are respectively Research
Associate and Senior Research Associate of the Belgian F. R. S.- FNRS.
Financial support from this organization is acknowledged.
NR 31
TC 24
Z9 24
U1 0
U2 5
PU IOP PUBLISHING LTD
PI BRISTOL
PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND
SN 0067-0049
J9 ASTROPHYS J SUPPL S
JI Astrophys. J. Suppl. Ser.
PD MAY
PY 2009
VL 182
IS 1
BP 127
EP 130
DI 10.1088/0067-0049/182/1/127
PG 4
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 442BX
UT WOS:000265815900008
ER
PT J
AU Hogrefe, C
Lynn, B
Goldberg, R
Rosenzweig, C
Zalewsky, E
Hao, W
Doraiswamy, P
Civerolo, K
Ku, JY
Sistla, G
Kinney, PL
AF Hogrefe, Christian
Lynn, Barry
Goldberg, Richard
Rosenzweig, Cynthia
Zalewsky, Eric
Hao, Winston
Doraiswamy, Prakash
Civerolo, Kevin
Ku, Jia-Yeong
Sistla, Gopal
Kinney, P. L.
TI A combined model-observation approach to estimate historic gridded
fields of PM2.5 mass and species concentrations
SO ATMOSPHERIC ENVIRONMENT
LA English
DT Article
DE Long-term air quality modeling; Aerosol model evaluation; Air quality
characterization; Data integration; Community Multiscale; Air Quality
(CMAQ) model
ID COMMUNITY-MULTISCALE-AIR; SOUTHEASTERN UNITED-STATES; PARTICULATE
MATTER; PERFORMANCE EVALUATION; QUALITY MODELS; PART II; OZONE; CMAQ;
MORTALITY; EXPOSURE
AB This paper introduces a methodology for estimating gridded fields of total and speciated fine particulate matter (PM2.5) concentrations for time periods and regions not covered by observational data. The methodology is based on performing long-term regional scale meteorological and air quality simulations and then integrating these simulations with available observational data. To illustrate this methodology, we present an application in which year-round simulations with a meteorological model (the National Center for Atmospheric Research/Penn State Mesoscale Model, hereafter referred to as MM5) and a photochemical air quality model (the Community Multiscale Air Quality Model, hereafter referred to as CMAQ) have been performed over the northeastern United States for 1988-2005. Model evaluation results for total PM2.5 mass and individual species for the time period from 2000 to 2005 show that model performance varies by species, season, and location. Therefore, an approach is developed to adjust CMAQ output with factors based on these three variables. The adjusted model values for total PM2.5 mass for 2000-2005 are compared against independent measurements not utilized for the adjustment approach. This comparison reveals that the adjusted model values have a lower root mean square error (RMSE) and higher correlation coefficients than the original model values. Furthermore, the PM2.5 estimates from these adjusted model values are compared against an alternate method for estimating historic PM2.5 values that is based on PM2.5/PM10 ratios calculated at co-located monitors. Results reveal that both methods yield estimates of historic PM2.5 mass that are broadly consistent; however, the adjusted CMAQ values provide greater spatial coverage and information for PM2.5 species in addition to total PM2.5 mass. Finally, strengths and limitations of the proposed approach are discussed in the context of potential uses of this method. (C) 2009 Elsevier Ltd. All rights reserved.
C1 [Hogrefe, Christian; Zalewsky, Eric; Hao, Winston; Ku, Jia-Yeong; Sistla, Gopal] Bur Air Qual Anal & Res, New York State Dept Environm Conservat, Albany, NY 12233 USA.
[Hogrefe, Christian; Doraiswamy, Prakash] SUNY Albany, Atmospher Sci Res Ctr, Albany, NY 12203 USA.
[Lynn, Barry] Weather It Is LTD, Efrat, Israel.
[Goldberg, Richard; Rosenzweig, Cynthia] NASA, Goddard Inst Space Studies, New York, NY 10025 USA.
[Kinney, P. L.] Columbia Univ, Mailman Sch Publ Hlth, New York, NY 10032 USA.
RP Hogrefe, C (reprint author), Bur Air Qual Anal & Res, New York State Dept Environm Conservat, 625 Broadway, Albany, NY 12233 USA.
EM chogrefe@dec.state.ny.us
RI Kinney, Patrick/H-7914-2012;
OI Civerolo, Kevin/0000-0003-1536-2664
FU National Oceanic and Atmospheric Administration [NAO40AR4310185185]; Oak
Ridge Institute for Science and Education (ORISE)
FX The work presented here was supported by the National Oceanic and
Atmospheric Administration under award NAO40AR4310185185, but it has not
been subjected to its required peer and policy review. Therefore, the
statements, findings, conclusions, and recommendations are those of the
authors and do not necessarily reflect the views of the sponsoring
agency and no official endorsement should be inferred. Additionally,
part of the work presented in this paper was performed by the New York
State Department of Environmental Conservation, but the views expressed
in this paper do not necessarily reflect the views or policies of the
New York State Department of Environmental Conservation. Finally,
Christian Hogrefe also gratefully acknowledges partial support for this
work through a research fellowship from the Oak Ridge Institute for
Science and Education (ORISE).
NR 30
TC 27
Z9 28
U1 0
U2 11
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 MAY
PY 2009
VL 43
IS 16
BP 2561
EP 2570
DI 10.1016/j.atmosenv.2009.02.031
PG 10
WC Environmental Sciences; Meteorology & Atmospheric Sciences
SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences
GA 448PA
UT WOS:000266273300006
ER
PT J
AU Platts, SH
Tuxhorn, JA
Ribeiro, LC
Stenger, MB
Lee, SMC
Meck, JV
AF Platts, Steven H.
Tuxhorn, Jennifer A.
Ribeiro, L. Christine
Stenger, Michael B.
Lee, Stuart M. C.
Meck, Janice V.
TI Compression Garments as Countermeasures to Orthostatic Intolerance
SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE
LA English
DT Article
DE hypovolemia; kentavr; anti-gravity suit; spaceflight; tilt test;
hypotension
ID SPACE-SHUTTLE REENTRY; SPACEFLIGHT; ASTRONAUTS; BLOOD; HYPOTENSION;
VOLUME; SUIT; MASS
AB Introduction: All astronauts experience some degree of orthostatic intolerance following spaceflight, ranging from tachycardia to orthostatic hypotension and syncope. The purpose of this study was to evaluate the ability of two compression garments, the National Aeronautics and Space Administration's inflatable antigravity suit (AGS) and the Russian Federal Space Agency's non-inflatable compression garment (Kentavr), to prevent hypovolemia-related orthostatic intolerance. Methods: To mimic the plasma Volume loss experience(] by astronauts during spaceflight 19 healthy Subjects received an intravenous close of a dliueretic, furosemide (0.5 mg . kg(-1)), and then consumed a low-salt diet for 36 h. Thereafter, subjects participated in a 15-min 80 degrees head-up tilt test wearing either the AGS (N = 9) or Kentavr (N = 10). Compression garments were used in the fashion recommended by the respective agencies, delivering similar to 78 mmHg and similar to 30 mmHg of compression in the AGS and Kentavr, respectively. Incidence of presyncope and hemodynamic responses during upright tilt were compared to a separate group of hypovolemic control subjects (N = 16). Results: Subjects wearing the AGS or Kentavr completed the full 15 min of upright tilt without incidence of orthostatic hypotension or presyncope. In contrast, only 9 control subject (56%) were able to complete the tilt test. in addition, both types of compression garments maintained systolic blood pressure and significantly reduced tilt-induced tachycardia and reductions in stroke volume. Conclusions: Although both garments Successfully countered hypovolemia-induced orthostatic intolerance, the Kentavr provided protection by using lower levels of compression. Determining the optimal compression level required for protection of intolerance may improve crewmember comfort and decrease restrictions on physical activities after spaceflight.
C1 [Platts, Steven H.; Meck, Janice V.] NASA, Lyndon B Johnson Space Ctr, Human Adaptat & Countermeasures Div, Houston, TX 77058 USA.
[Tuxhorn, Jennifer A.; Ribeiro, L. Christine; Stenger, Michael B.; Lee, Stuart M. C.] Integrated Sci & Engn Grp, Houston, TX USA.
RP Platts, SH (reprint author), NASA, Lyndon B Johnson Space Ctr, Human Adaptat & Countermeasures Div, 2101 NASA Pkwy,Mail Code SK, Houston, TX 77058 USA.
EM steven.platts-1@nasa.gov
FU NASA 3
FX The authors wish to thank the subjects for their participation in this
investigation, the staff of the JSC Cardiovascular Laboratory for the
collection and reduction of these data, Angela Brown for her assistance
with manuscript preparation, and NASA for financial Support of this
work.
NR 21
TC 16
Z9 19
U1 0
U2 5
PU AEROSPACE MEDICAL ASSOC
PI ALEXANDRIA
PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 USA
SN 0095-6562
J9 AVIAT SPACE ENVIR MD
JI Aviat. Space Environ. Med.
PD MAY
PY 2009
VL 80
IS 5
BP 437
EP 442
DI 10.3357/ASEM.2473.2009
PG 6
WC Public, Environmental & Occupational Health; Medicine, General &
Internal; Sport Sciences
SC Public, Environmental & Occupational Health; General & Internal
Medicine; Sport Sciences
GA 438JD
UT WOS:000265550800001
PM 19456003
ER
PT J
AU Crucian, BE
Stowe, RP
Mehta, SK
Yetman, DL
Leal, MJ
Quiriarte, HD
Pierson, DL
Sams, CF
AF Crucian, Brian E.
Stowe, Raymond P.
Mehta, Satish K.
Yetman, Deborah L.
Leal, Melanie J.
Quiriarte, Heather D.
Pierson, Duane L.
Sams, Clarence F.
TI Immune Status, Latent Viral Reactivation, and Stress During
Long-Duration Head-Down Bed Rest
SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE
LA English
DT Article
DE immune function; cytokines; viral reactivation; microgravity
ID EPSTEIN-BARR-VIRUS; TIME PCR ASSAY; SPACE-FLIGHT; QUANTITATIVE-ANALYSIS;
PERIPHERAL-BLOOD; SYSTEM CHANGES; SPACEFLIGHT; ASTRONAUTS; RESPONSES;
MICROGRAVITY
AB Introduction: As logistical access for space research becomes more limited and NASA prepares for exploration-class missions, ground-based spaceflight analogs will increase in importance for biomedical countermeasures development. A monitoring of immune parameters was performed during the NASA Flight Analogs Project bed rest study (without countermeasure); to establish 'control' data against Which future studies (with countermeasure) will he evaluated. Some of the countermeasures planned to be evaluated in future studies may impact immune function. Methods: The immune assessment consisted of leukocyte subset distribution, early T cell activation, intracellular cytokine profiles, latent viral reactivation, virus specific T cell levels and function, stress hormone levels and a behavioral assessment using stress questionnaires. Results: in general, subjects did riot display altered peripheral leukocyte subsets, constitutive immune activation, altered T cell function, or significant latent viral reactivation (EBV, VZV). Levels of constitutively activated T cells (CD8+/CD69+) and virus-specific T cells (CMV and EBV) decreased during the study. Cortisol levels (plasma and saliva) did not vary significantly during 90-d bed rest. Conclusions: These data demonstrate the absence of significant immune system alteration and physiological stress during 90-d bed rest, and establish control data against which future Studies (including countermeasures) may be compared.
C1 [Pierson, Duane L.; Sams, Clarence F.] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA.
[Crucian, Brian E.] Wyle, Houston, TX USA.
[Stowe, Raymond P.; Yetman, Deborah L.] Microgen Labs, Lamarque, TX USA.
[Mehta, Satish K.; Leal, Melanie J.] Enterprise Advisory Serv Inc, Houston, TX USA.
[Quiriarte, Heather D.] JES Tech, Houston, TX USA.
RP Sams, CF (reprint author), NASA, Lyndon B Johnson Space Ctr, 2101 NASA Pkwy,Mail Code SK3, Houston, TX 77058 USA.
EM csams@nasa.gov
FU NASA Flight Analogs Project [M01 RR 0073]
FX Sponsored by the NASA Flight Analogs Project and conducted at the
NIH-funded (M01 RR 0073) General Clinical Research Center at the
University of Texas Medical Branch, Galveston, TX.
NR 31
TC 19
Z9 20
U1 0
U2 6
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 MAY
PY 2009
VL 80
IS 5
BP A37
EP A44
DI 10.3357/ASEM.BR05.2009
PG 8
WC Public, Environmental & Occupational Health; Medicine, General &
Internal; Sport Sciences
SC Public, Environmental & Occupational Health; General & Internal
Medicine; Sport Sciences
GA 438JE
UT WOS:000265550900006
PM 19476168
ER
PT J
AU Inniss, AM
Rice, BL
Smith, SM
AF Inniss, Astrid M.
Rice, Barbara L.
Smith, Scott M.
TI Dietary Support of Long-Duration Head-Down Bed Rest
SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE
LA English
DT Article
DE nutrition; food support; menu planning; bed rest
ID MASS
AB Introduction: Dietary control and nutrient intake are critical aspects of any metabolic study, but this is especially true in the case of bed rest studies. We Sought to define nutritional requirements, develop menus, and implement them during long-duration head-down bed rest studies. Methods: The dietary goals were to provide 100%, of subjects' nutrient requirements and to maintain subjects' bodyweight to within 3% of their weight on the third clay of head-down bed rest. The research dietitian and metabolic kitchen staff are an important part of the multidisciplinary team required to implement a bed rest study. Results. We report herein the planning steps and nutrient intake results from 13 subjects. We also provide insight into some of the dietary challenges that arise during long-duration bed rest studies. Discussion: Regardless of the overall objective of the bed rest study to be performed, nutrition must be carefully planned, implemented, and monitored to prevent results from being compromised.
C1 [Inniss, Astrid M.] Univ Texas Med Branch, Gen Clin Res Ctr, Galveston, TX USA.
[Rice, Barbara L.] Enterprise Advisory Serv Inc, Houston, TX USA.
[Smith, Scott M.] NASA, Lyndon B Johnson Space Ctr, Human Adaptat & Countermeasures Div, Houston, TX USA.
EM aminniss@utmb.edu
FU NCATS NIH HHS [UL1 TR000071]; NCRR NIH HHS [UL1 RR029876]
NR 15
TC 19
Z9 19
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 MAY
PY 2009
VL 80
IS 5
SU S
BP A9
EP A14
DI 10.3357/ASEM.BR04.2009
PG 6
WC Public, Environmental & Occupational Health; Medicine, General &
Internal; Sport Sciences
SC Public, Environmental & Occupational Health; General & Internal
Medicine; Sport Sciences
GA 438JE
UT WOS:000265550900002
PM 19476164
ER
PT J
AU Meck, JV
Dreyer, SA
Warren, LE
AF Meck, Janice V.
Dreyer, Sherlene A.
Warren, L. Elisabeth
TI Long-Duration Head-Down Bed Rest: Project Overview, Vital Signs, and
Fluid Balance
SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE
LA English
DT Article
DE fluid balance; blood pressure; heart rate
AB Introduction: Spaceflight has profound effects on the human body. Many of these effects can be induced with head-clown bed rest, which has been a Useful ground-based analog. With limited resources aboard the International Space Station for human research, the bed rest analog will be a primary platform On Which countermeasures will be developed and tested for lunar and Mars mission scenarios. Methods: NASA Johnson Space Center, in conjunction with the University of Texas Medical Branch (UTMB), has created the NASA Flight Analogs Project (FAP), a research program with the overall objective Of using head-clown bed rest to evaluate, compare, and refine candidate countermeasures to space-flight deconditioning. This paper serves as an overview and describes the standard conditions, the standard set of subject screening criteria, and the standard set of measurements for all FAP bed rest Subjects. Results: Heart rate and diastolic pressures decreased transiently at the onset of bed rest. Fluid balance showed an early diuresis, which stabilized within 3 d. In this supplement, detailed results from Multiple disciplines are presented in a series of reports. Discussion: The following reports describe multi-disciplinary results from the standard measurements by which the responses to bed rest will be assessed and by which countermeasures will be evaluated. The data presented in this overview are meant to serve as a context in which to view the data presented in the discipline specific manuscripts. The dietary support and behavioral health papers provide additional information regarding those aspects of implementing bed rest studies successfully.
C1 [Meck, Janice V.] NASA, Lyndon B Johnson Space Ctr, Human Adaptat & Countermeasures Div, Houston, TX 77058 USA.
[Dreyer, Sherlene A.; Warren, L. Elisabeth] Univ Space Res Assoc, Houston, TX USA.
RP Meck, JV (reprint author), NASA, Lyndon B Johnson Space Ctr, Human Adaptat & Countermeasures Div, Mail Code SK3,2101 NASA Pkwy, Houston, TX 77058 USA.
EM janice.v.meck@nasa.gov
FU NASA Flight Analogs Project [M01 RR 0073]
FX No project of this magnitude and complexity could succeed without
tremendous Support. We are indebted to the UTMB GCRC staff; David Ware,
M.D., our attending physician; the Johnson Space Center research
laboratories; Wvle Laboratories Integration Coordinators; and, most of
all, Our Subjects. Sponsored by the NASA Flight Analogs Project;
conducted at the NIH-funded (M01 RR 0073) General Clinical Research
Center at the University of Texas Medical Branch, Galveston, TX.
NR 12
TC 37
Z9 40
U1 1
U2 2
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 MAY
PY 2009
VL 80
IS 5
BP A1
EP A8
DI 10.3357/ASEM.BR01.2009
PG 8
WC Public, Environmental & Occupational Health; Medicine, General &
Internal; Sport Sciences
SC Public, Environmental & Occupational Health; General & Internal
Medicine; Sport Sciences
GA 438JE
UT WOS:000265550900001
PM 19476163
ER
PT J
AU Platts, SH
Martin, DS
Stenger, MB
Perez, SA
Ribeiro, LC
Summers, R
Meck, JV
AF Platts, Steven H.
Martin, David S.
Stenger, Michael B.
Perez, Sondra A.
Ribeiro, L. Christine
Summers, Richard
Meck, Janice V.
TI Cardiovascular Adaptations to Long-Duration Head-Down Bed Rest
SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE
LA English
DT Article
DE spaceflight; orthostatic intolerance; hypotension; fluid-shift; plasma
volume
ID POSTSPACEFLIGHT ORTHOSTATIC HYPOTENSION; CARDIAC-OUTPUT; SPACEFLIGHT;
MICROGRAVITY; ASTRONAUTS; INTOLERANCE; ARTERIOLES; MECHANISMS;
EXPRESSION; EXERCISE
AB Introduction: Orthostatic hypotension is a serious risk for crewmembers returning from spaceflight. Numerous cardiovascular mechanisms have been proposed to account for this problem, including vascular and cardiac dysfunction, which we studied during bed rest, Methods: Thirteen subjects were studied before and during bed rest. Statistical analysis was limited to the first 49-60 d of bed rest and compared to pre-bed rest data. Ultrasound data were collected on Vascular and cardiac structure and function. Tilt testing was conducted for 30 min or until presyncopal symptoms intervened. Results: Plasma volume was significantly reduced (151%) by day 7 of bed rest. Flow-mediated dilation in the leg was significantly increased at bed rest clay 49 (6% from pre-bed rest). Arterial responses to nitroglycerin differed in the arm and leg, but did not change as a result of bed rest. Anterior tibial artery intimal-medial thickness markedly decreased at bed rest days 21 (21%), 35 (22%), and 49 (19%). Several cardiac functional parameters, including isovolumic relaxation time (73 ms to 85 ms at clay 7) and myocardial performance index, were significantly increased (0.41 to 0.49 by day 7 of bed rest; indicating a decrease in cardiac function) during bed rest. There was a trend for decreased orthostatic tolerance following 60 d of bed rest (P = 0.1). Discussion: Our data Suggest that bed rest altered cardiovascular structure and function in a pattern similar to short-duration spaceflight. Additionally, the vascular alterations were primarily seen in the lower body, while vessels of the upper body were unaffected.
C1 [Platts, Steven H.; Meck, Janice V.] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA.
[Martin, David S.; Stenger, Michael B.; Perez, Sondra A.; Ribeiro, L. Christine] Wyle Integrated Sci & Engn, Houston, TX USA.
[Summers, Richard] Univ Mississippi, University, MS 38677 USA.
RP Platts, SH (reprint author), NASA, Lyndon B Johnson Space Ctr, Mail Code SK,2101 NASA Pkwy, Houston, TX 77058 USA.
EM steven.platts-1@nasa.gov
FU NASA Flight Analogs Project [M01 RR 0073]; NASA [NAS9-97005]
FX Sponsored by the NASA Flight Analogs Project; conducted at the
NEH-funded (M01 RR 0073) GCRC at the University of Texas Medical Branch,
Galveston, TX, and NASA grant NAS9-97005 to JVM.
NR 30
TC 30
Z9 32
U1 0
U2 6
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 MAY
PY 2009
VL 80
IS 5
BP A29
EP A36
DI 10.3357/ASEM.BR03.2009
PG 8
WC Public, Environmental & Occupational Health; Medicine, General &
Internal; Sport Sciences
SC Public, Environmental & Occupational Health; General & Internal
Medicine; Sport Sciences
GA 438JE
UT WOS:000265550900005
PM 19476167
ER
PT J
AU Reschke, MF
Bloomberg, JJ
Paloski, WH
Mulavara, AP
Feiveson, AH
Harm, DL
AF Reschke, Millard F.
Bloomberg, Jacob J.
Paloski, William H.
Mulavara, Ajitkumar P.
Feiveson, Alan H.
Harm, Deborah L.
TI Postural Reflexes, Balance Control, and Functional Mobility with
Long-Duration Head-Down Bed Rest
SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE
LA English
DT Article
DE spaceflight; stretch reflex; functional reflex; exclusionary hypothesis;
microgravity; flight analog; posturography; sensorimotor
ID INPUT; WEIGHTLESSNESS; MICROGRAVITY; SENSORIMOTOR; LOCOMOTION; GAIT
AB Introduction: Spaceflight has functionally significant effects oil sensorimotor behavior, but it is difficult to separate the effects of ascending somatosensory changes caused 1)), postural muscle and plantar surface unloading from descending visual-vestibular neural changes. To differentiate somatosensory changes from graviceptor changes in post-spaceflight sensorimotor behavior, bed rest may serve as an exclusionary analog to spaceflight. Methods: Four separate tests were used to measure changes in sensorimotor performance: 1) the monosynaptic stretch reflex (MSR); 2) the functional stretch reflex (FSR); 3) balance control parameters associated with computerized dynamic posturography (CDP); and 4) a functional mobility test (FMT). Results: A mixed model regression analysis showed significant increases in median MSR start and peak latencies, while the median FSR latency showed no significant increase. Median MSR peak magnitude showed a significant increase during the middle bed rest period (19-60 d). There were no significant effects of bed rest on balance control, but some indication that dynamic head movements may affect posture after bed rest. Time to complete the course for the FMT increased significantly with bed rest. Discussion: The four primary tests indicate that long-duration head-clown bed rest, through unloading and modification of the body's support surface, serves as an exclusionary analog for sensorimotor responses to spaceflight. Furthermore, the data Suggest that procedures designed to alleviate modifications to the sensory substrate serving the soles of the feet may provide a countermeasure to hell) maintain support afferentation of the postural muscles.
C1 [Reschke, Millard F.; Bloomberg, Jacob J.; Paloski, William H.; Harm, Deborah L.] NASA, Lyndon B Johnson Space Ctr, Neurosci Labs, Houston, TX 77058 USA.
[Feiveson, Alan H.] NASA, Lyndon B Johnson Space Ctr, Human Adaptat & Countermeasures Div, Houston, TX 77058 USA.
[Mulavara, Ajitkumar P.] Univ Space Res Assoc, Houston, TX USA.
RP Reschke, MF (reprint author), NASA, Lyndon B Johnson Space Ctr, Neurosci Labs, Mail Code SK272,2101 NASA Pkwy, Houston, TX 77058 USA.
EM millard.f.reschke@nasa.gov
FU NASA Flight Analogs Project [M01 RR 0073]
FX The USO of our sensorimotor test paradigms as standard measures for
head-down bed rest would not have been possible Without the support of
NASA's Flight Analogs Project Team. We would also like to thank the
Subjects who persisted throughout the bed rest, and the staff of the
UTMB General Clinical Research Center for their Support and assistance.
Sponsored by the NASA Flight Analogs Project; conducted at the
NTH-funded (M01 RR 0073) General Clinical Research Center at the
University of Texas Medical Branch, Galveston, TX. Lastly and most
importantly, we are greatly indebted to Danielle L. Blau v; Rachel A.
Brady; Elizabeth A. Fisher; George A. Ford; Jody M. Krnavek; Jeffrey T.
Somers; and Laura C. Taylor. Without the service and long hours these
individuals dedicated to this research project, the software, hardware,
and data presented in this paper would net have been possible.
NR 32
TC 16
Z9 19
U1 0
U2 3
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 MAY
PY 2009
VL 80
IS 5
BP A45
EP A54
DI 10.3357/ASEM.BR06.2009
PG 10
WC Public, Environmental & Occupational Health; Medicine, General &
Internal; Sport Sciences
SC Public, Environmental & Occupational Health; General & Internal
Medicine; Sport Sciences
GA 438JE
UT WOS:000265550900007
PM 19476169
ER
PT J
AU Seaton, KA
Bowie, KE
Sipes, WA
AF Seaton, Kimberly A.
Bowie, Kendra E.
Sipes, Walter A.
TI Behavioral and Psychological Issues in Long-Duration Head-Down Bed Rest
SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE
LA English
DT Article
DE spaceflight; emotional support
ID GROUP-DYNAMICS; CONFINEMENT; EXEMSI; SPACE
AB Introduction: This report is one of a series on the Flight Analogs Project, which is designed to lay the groundwork for a standard bed rest protocol. Behavioral health services, similar to those offered to the U.S. astronauts who undertake 6-mo missions onboard the international Space Station, were provided to 13 long-duration head-down bed rest participants. Long-duration missions pose unique challenges and stressors, including separation from primary Support group, monotonous environment, and loss of privacy and autonomy. Methods: The psychological services team, consisting of a psychiatrist, a psychologist, and a master's level psychological support scientist, provided behavioral health services throughout all phases of the Flight Analogs Project (FAP) long-duration head-down bed rest study. During the initial screening phase, potential candidates completed 4 h of psychological testing and a 1.5-h clinical interview with a psychologist to assess their psychological fitness and ability to complete the Study Successfully. Additionally, the psychological services team provided pre-admission trainings on time management, stress management, and communication skills and conflict resolution. Throughout their stay on the research unit, study participants received regular individual and group visits from the psychological services team. Training was also provided to study personnel to address personality and behavioral management challenges. Results: Psychological support and training provided to both subjects and Study personnel have successfully improved the well being Of Study participants. Discussion: Behavioral health services are indispensable to long-duration head-down bed rest studies.
C1 [Seaton, Kimberly A.; Bowie, Kendra E.] Wyle, Houston, TX 77058 USA.
[Seaton, Kimberly A.] Univ Texas Med Branch, Galveston, TX USA.
[Sipes, Walter A.] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA.
RP Seaton, KA (reprint author), Wyle, 1290 Hercules Blvd, Houston, TX 77058 USA.
EM kseaton@wylehou.com
FU NASA Flight Analogs Project [M01 RR 0073]
FX Sponsored by the NASA Flight Analogs Project; conducted at the
NIH-funded (M01 RR 0073) General Clinical Research Center at the
University of Texas Medical Branch, Galveston, TX.
NR 19
TC 5
Z9 6
U1 1
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 MAY
PY 2009
VL 80
IS 5
BP A55
EP A61
DI 10.3357/ASEM.BR08.2009
PG 7
WC Public, Environmental & Occupational Health; Medicine, General &
Internal; Sport Sciences
SC Public, Environmental & Occupational Health; General & Internal
Medicine; Sport Sciences
GA 438JE
UT WOS:000265550900008
PM 19476170
ER
PT J
AU Seaton, KA
Slack, KJ
Sipes, WA
Bowie, KE
AF Seaton, Kimberly A.
Slack, Kelley J.
Sipes, Walter A.
Bowie, Kendra E.
TI Cognitive Functioning In Long-Duration Head-Down Bed Rest
SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE
LA English
DT Article
DE WinSCAT; spaceflight; cognitive function assessment tool
AB Introduction: This report is one of a series on the Flight Analog Project, which is designed to lay the groundwork for a standard bed rest protocol. The Spaceflight Cognitive Assessment Tool for Windows (WinSCAT) is a self-administered battery of tests used on the International Space Station for evaluating cognitive functioning. Here, WinSCAT was used to assess cognitive functioning during extended head-down bed rest. Methods: There were 13 subjects who participated in 60 or 90 d of head-down bed rest and took WinSCAT during the pre-bed rest phase, the in-bed rest phase, and the post-bed rest (reconditioning) phase of study participation. Results: After adjusting for individual baseline performance, 12 off-nominal scores were observed out of 351 total observations during bed rest and 7 of 180 during reconditioning. No evidence was found for systematic changes in off-nominal incidence as time in bed rest progressed, or during the reconditioning period. Discussion: Cognitive functioning does not appear to be adversely affected by long-duration head-clown bed rest. individual differences in underlying cognitive ability and motivation level are likely explanations for the current findings.
C1 [Seaton, Kimberly A.; Bowie, Kendra E.] Wyle, Houston, TX 77058 USA.
[Seaton, Kimberly A.] Univ Texas Med Branch, Galveston, TX USA.
[Slack, Kelley J.] LZ Technol, Alvin, TX USA.
[Sipes, Walter A.] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA.
RP Seaton, KA (reprint author), Wyle, 1290 Hercules Blvd, Houston, TX 77058 USA.
EM kseaton@wylehou.com
FU NASA Flight Analogs Project [M01 RR 0073]
FX Sponsored by the NASA Flight Analogs Project; conducted at the
NIFI-funded (M01 RR 0073) General Clinical Research Center at the
University of Texas Medical Branch, Galveston, TX.
NR 5
TC 12
Z9 16
U1 0
U2 3
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 MAY
PY 2009
VL 80
IS 5
BP A62
EP A65
DI 10.3357/ASEM.BR09.2009
PG 4
WC Public, Environmental & Occupational Health; Medicine, General &
Internal; Sport Sciences
SC Public, Environmental & Occupational Health; General & Internal
Medicine; Sport Sciences
GA 438JE
UT WOS:000265550900009
PM 19476171
ER
PT J
AU Spector, ER
Smith, SM
Sibonga, JD
AF Spector, Elisabeth R.
Smith, Scott M.
Sibonga, Jean D.
TI Skeletal Effects of Long-Duration Head-Down Red Rest
SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE
LA English
DT Article
DE microgravity; disuse; bone mineral density; BMD recovery; bone
resorption; bone formation
ID BONE-MINERAL DENSITY; BIOCHEMICAL MARKERS; BED REST; SPACEFLIGHT;
RECOVERY; TURNOVER
AB Introduction: Skeletal unloading during spaceflight causes regional loss of bone mineral density (BMD), primarily in the spine and lower body regions. This loss of skeletal mass could adversely affect crew health during and after spaceflight and jeopardize mission success. Bed rest has long been used as a spaceflight analog to study the effects of disuse oil many body systems, including the skeleton. This study was undertaken by the NASA Flight Analogs Project (FAP) to collect control data for up-coming Countermeasure studies. Methods: There were 13 subjects who participated in 42, 44, 49, 52, 60, or 90 d of continuous, head-clown bed rest. DXA scans (dual-energy X-ray absorptiometry) were obtained before and after bed rest to measure changes in BMD of the whole body, lumbar spine, hip, heel, and wrist; the 90-d subjects were also scanned at the 60-d time point. Follow-up DXA scans were performed after 6 mo and 12 mo of reambulation to assess BMD recovery. Results: BMD changes were consistent with earlier bed rest and spaceflight studies, with statistically significant losses averaging 1% per month in the hip, pelvis, and heel. Recovery data were also consistent with data obtained after spaceflight. Bone biomarker data are described, and support the findings of previous studies. Specifically, the process of normal bone remodeling is uncoupled: increased bone resorption with no concomitant change in bone formation. Conclusion: The FAP appears to be a valid test bed for skeletal disuse studies, and should provide a useful research platform for evaluating countermeasures to spaceflight-induced bone loss.
C1 [Sibonga, Jean D.] NASA, Lyndon B Johnson Space Ctr, Bone & Mineral Lab, Human Adaptat & Countermeasures Div, Houston, TX 77058 USA.
[Spector, Elisabeth R.] Wyle, Houston, TX USA.
[Sibonga, Jean D.] Univ Space Res Assoc, Houston, TX USA.
RP Sibonga, JD (reprint author), NASA, Lyndon B Johnson Space Ctr, Bone & Mineral Lab, Human Adaptat & Countermeasures Div, Mail Code SK-272,2101 NASA Pkwy, Houston, TX 77058 USA.
EM jean.sibonga-1@nasa.gov
FU NASA Flight Analogs Project [M01 RR 0073]
FX Sponsored by the NASA Flight Analogs Project; conducted at the
NIH-funded (M01 RR 0073) General Clinical Research Center at the
University of Texas Medical Branch, Galveston, TX.
NR 20
TC 31
Z9 31
U1 0
U2 8
PU AEROSPACE MEDICAL ASSOC
PI ALEXANDRIA
PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 USA
SN 0095-6562
EI 1943-4448
J9 AVIAT SPACE ENVIR MD
JI Aviat. Space Environ. Med.
PD MAY
PY 2009
VL 80
IS 5
SU S
BP A23
EP A28
DI 10.3357/ASEM.BR02.2009
PG 6
WC Public, Environmental & Occupational Health; Medicine, General &
Internal; Sport Sciences
SC Public, Environmental & Occupational Health; General & Internal
Medicine; Sport Sciences
GA 438JE
UT WOS:000265550900004
PM 19476166
ER
PT J
AU Zwart, SR
Oliver, SAM
Fesperman, JV
Kala, G
Krauhs, J
Ericson, K
Smith, SM
AF Zwart, Sara R.
Oliver, Susan A. Mathews
Fesperman, J. Vernell
Kala, Geeta
Krauhs, Jane
Ericson, Karen
Smith, Scott M.
TI Nutritional Status Assessment Before, During, and After Long-Duration
Head-Down Bed Rest
SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE
LA English
DT Article
DE spaceflight; nutrition; weightlessness; bone resorption; parathyroid
hormone; oxidative stress; antioxidants; iron; transferrin
ID RED-BLOOD-CELL; SPACE-FLIGHT; BONE TURNOVER; CALCIUM-METABOLISM;
SPACEFLIGHT; MARKERS; HUMANS; WEIGHTLESSNESS; UROLITHIASIS; BIOCHEMISTRY
AB Introduction: Bed rest is a valuable ground-based model for many of the physiological changes that are associated with spaceflight. Nutritional changes during and after 60 or 90 cl of head-down bed rest were evaluated. Methods: A total of 13 subjects (8 men, 5 women; ages 2654 yr) participated in either 60 or 90 d of bed rest. Blood and urine were collected twice before bed rest and about once per month during bed rest. Samples were stored frozen and batch analyzed. Data were analyzed using repeated-measures analysis of variance. Results: During bed rest, markers of bone resorption (such as N-telopeptide excretion, P < 0.001) increased and serum concentration of parathyroid hormone decreased (P < 0.001). Also, oxidative damage markers such as superoxide dismutase increased (P < 0.05), and after 90 d of bed rest, total antioxidant capacity decreased (P < 0.05). During bed rest, iron status indices showed patterns of increased iron stores with a decreased concentration of transferrin receptors (P < 0.01). Discussion: These changes are similar to some of those observed during spaceflight, and further document the utility of bed rest as a model of spaceflight.
C1 [Smith, Scott M.] NASA, Lyndon B Johnson Space Ctr, Nutr Biochem Lab, Human Adaptat & Countermeasures Div, Houston, TX 77058 USA.
[Oliver, Susan A. Mathews; Fesperman, J. Vernell; Kala, Geeta] Enterprise Advisory Serv Inc, Houston, TX USA.
[Ericson, Karen] Indiana Univ Purdue Univ, Ft Wayne, IN 46805 USA.
[Zwart, Sara R.] Univ Space Res Assoc, Houston, TX USA.
[Krauhs, Jane] Wyle, Houston, TX USA.
RP Smith, SM (reprint author), NASA, Lyndon B Johnson Space Ctr, Nutr Biochem Lab, Human Adaptat & Countermeasures Div, Mail Code SK,2101 NASA Pkwy, Houston, TX 77058 USA.
EM scott.m.smith@nasa.gov
FU NASA Flight Analogs Project [M01 RR 0073]
FX This project would not have been possible Without the NASA Flight
Analogs Project Team. The effort to develop standardized bed rest
conditions was not an easy one, and Jan Meck and her team did a
phenomenal job with this project-hurricanes notwithstanding. We also
thank the Subjects for their time and willingness to participate in
these difficult long-duration Studies. We thank the staff of the UTMB
General Clinical Research Center for their assistance in the conduct of
this Study, The efforts of the staff of die NASA Johnson Space Center
Nutritional Biochemistry Laboratory in planning, integrating, and
executing the biological sample processing, laboratory analyses, and
management of a tremendous amount of data are very much appreciated. We
also thank Janis Davis-Street for reviewing the manuscript. Sponsored by
the NASA Flight Analogs Project; conducted at the NIH-funded (M01 RR
0073) General Clinical Research Center at the University of Texas
Medical Branch, Galveston, TX.
NR 45
TC 26
Z9 26
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 MAY
PY 2009
VL 80
IS 5
BP A15
EP A22
DI 10.3357/ASEM.BR07.2009
PG 8
WC Public, Environmental & Occupational Health; Medicine, General &
Internal; Sport Sciences
SC Public, Environmental & Occupational Health; General & Internal
Medicine; Sport Sciences
GA 438JE
UT WOS:000265550900003
PM 19476165
ER
PT J
AU Campbell, JR
Welton, EJ
Spinhirne, JD
AF Campbell, James R.
Welton, Ellsworth J.
Spinhirne, James D.
TI Continuous Lidar Monitoring of Polar Stratospheric Clouds at the South
Pole
SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY
LA English
DT Editorial Material
ID MICROPULSE LIDAR; DENITRIFICATION
C1 [Campbell, James R.] Univ Corp Atmospher Res, USN, Res Lab, Visiting Scientist Programs, Monterey, CA 93943 USA.
[Welton, Ellsworth J.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
[Spinhirne, James D.] Univ Arizona, Dept Elect & Comp Engn, Tucson, AZ 85721 USA.
RP Campbell, JR (reprint author), Univ Corp Atmospher Res, USN, Res Lab, Visiting Scientist Programs, Monterey, CA 93943 USA.
EM jamesc@ucar.edu
RI Welton, Ellsworth/A-8362-2012; Campbell, James/C-4884-2012
OI Campbell, James/0000-0003-0251-4550
NR 13
TC 1
Z9 2
U1 0
U2 0
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 MAY
PY 2009
VL 90
IS 5
BP 613
EP 617
DI 10.1175/2008BAMS2754.1
PG 5
WC Meteorology & Atmospheric Sciences
SC Meteorology & Atmospheric Sciences
GA 462LR
UT WOS:000267354800003
ER
PT J
AU Pearson, JC
Brauer, CS
Drouin, BJ
Xu, LH
AF Pearson, J. C.
Brauer, C. S.
Drouin, Brian J.
Xu, Li-Hong
TI The rotational spectrum of methanol in the third excited torsional state
SO CANADIAN JOURNAL OF PHYSICS
LA English
DT Article
ID MICROWAVE STARK SPECTROSCOPY; FOURIER-TRANSFORM SPECTRA; FAR-INFRARED
SPECTROSCOPY; DIPOLE-MOMENT; CH3OH; CH3-ROCKING; DATABASE; MASERS; LINE;
BAND
AB The rotational spectrum of methanol in its third excited torsional state, nu(t) = 3, as well as the K = 0 A-state of nu(t) = 4, has been recorded and analyzed in the 8-1654 GHz frequency range. The nu(t) = 3 state lies well above the top of the torsional barrier and the majority of the energy origins for the various K sub-bands lie below the C-O stretching fundamental vibration. Only the a-type R-branch spectrum was observed in this frequency range, suggesting that the near torsional degeneracy required for a b-type spectrum in the microwave accidentally reduces the torsional overlap, making these transitions very weak. The A-state K = 4 of nu(t) = 3 interaction with the C-O stretch torsional ground state K = 0(+) and K = 1(+) has been accounted for. The E-state K = -5 level could be fit directly with a power series in spite of its resonance with the C-O stretch torsional ground state K = -5 level. The (a)R-branch of the K = 0 A-state nu(t) = 4 sub-band is also provided and the origin of this band resonance with the C-O stretch is discussed. The data have been modeled with a power series to near experimental accuracy. The measured and calculated spectrum should facilitate radio astronomical assignments of nu(t) = 3 transitions in hot sources.
C1 [Pearson, J. C.; Brauer, C. S.; Drouin, Brian J.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
[Xu, Li-Hong] Univ New Brunswick, Dept Phys, CLAMS, St John, NB E2L 4L5, Canada.
RP Pearson, JC (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA.
EM john.c.pearson@jpl.nasa.gov
RI Xu, Li-Hong/J-5095-2015
FU Natural Sciences and Engineering Research Council of Canada
FX Portions of research described in this paper were carried out at the Jet
Propulsion Laboratory, California Institute of Technology, under
contract with the National Aeronautics and Space Administration (NASA).
We thank NASA for their support of Herschel heterodyne instrument for
far-infrared guaranteed time holders, which facilitated this paper. LHX
thanks the Natural Sciences and Engineering Research Council of Canada
for financial support of this research.
NR 31
TC 11
Z9 11
U1 0
U2 12
PU NATL RESEARCH COUNCIL CANADA-N R C RESEARCH PRESS
PI OTTAWA
PA BUILDING M 55, OTTAWA, ON K1A 0R6, CANADA
SN 0008-4204
J9 CAN J PHYS
JI Can. J. Phys.
PD MAY
PY 2009
VL 87
IS 5
BP 449
EP 467
DI 10.1139/P08-133
PG 19
WC Physics, Multidisciplinary
SC Physics
GA 494RV
UT WOS:000269834000006
ER
PT J
AU Sung, K
Brown, LR
Toth, RA
Crawford, TJ
AF Sung, Keeyoon
Brown, Linda R.
Toth, Robert A.
Crawford, Timothy J.
TI Fourier transform infrared spectroscopy measurements of H2O-broadened
half-widths of CO2 at 4.3 mu m
SO CANADIAN JOURNAL OF PHYSICS
LA English
DT Article
ID CONSTRAINED MULTISPECTRUM ANALYSIS; PRESSURE SHIFT COEFFICIENTS;
CARBON-DIOXIDE; SPEED DEPENDENCE; LINE POSITIONS; 4750-7000 CM(-1);
BANDS; TEMPERATURE; INTENSITIES; (CO2)-C-12-O-16
AB To support remote sensing of carbon dioxide in the troposphere, H2O pressure-broadened half-widths were obtained for 182 lines of CO2 in the 2250-2390 cm(-1) region. For this, six spectra of CO2 were recorded at 0.003 89 cm(-1) resolution using a Bruker IFS-125HR at the Jet Propulsion Laboratory. The absorption cell length was 6.14 cm, and the water pressures ranged from 20.1 to 26.5 torr (1 torr = 133.322 4 Pa) near room temperatures. Partial pressures of the species in the mixtures were determined by measuring selected line intensities in the nu(3) band of CO2 and the nu(2) band of H2O. Sample temperatures were validated by deriving rotational temperature from the nu(3) and nu(2) + nu(3) -nu(2) intensities of (CO2)-C-12 and those of CO (1-0). Positions, intensities, and half-widths were retrieved spectrum by spectrum using a nonlinear least-squares line-fitting algorithm, employing a standard Voigt line shape profile and an instrumental line shape consisting of a sinc function with aperture correction. Half-widths obtained for both the fundamental and the hot band of (CO2)-C-12 and the fundamental nu(3) band of (CO2)-C-13 had similar values. While half-widths of CO2 broadened by other atmospheric gases (such as N-2, O-2, CO2, and air) tend to decrease with increasing rotational quantum number J '', the H2O-broadened half-widths were observed to increase for intermediate J '' (8 <= J '' <= 42): similar to 0.127 cm(-1) atm(-1) near J '' = 8, and increasing to similar to 0.143 cm(-1) atm-1 (1 atm = 101.325 kPa) towards J '' = 42. Moreover, for 10 <= J '' <= 40, the empirical widths were within similar to 2%-3% of theoretical calculations. Since water vapor could reach up to 5% of ambient atmospheric surface pressure in the tropical regions, water broadened half-widths are required to model tropospheric CO2, particularly for high-precision remote sensing, to achieve a sub-percent precision in the measurements of CO2 column averaged mixing ratio. Since little vibrational dependence in line broadening has been seen, these results at 4.3 mu m can be used for other bands of CO2.
C1 [Sung, Keeyoon; Brown, Linda R.; Toth, Robert A.; Crawford, Timothy J.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
RP Sung, K (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA.
EM ksung@jpl.nasa.gov
RI Sung, Keeyoon/I-6533-2015
NR 39
TC 21
Z9 21
U1 1
U2 9
PU CANADIAN SCIENCE PUBLISHING, NRC RESEARCH PRESS
PI OTTAWA
PA 1200 MONTREAL ROAD, BUILDING M-55, OTTAWA, ON K1A 0R6, CANADA
SN 0008-4204
J9 CAN J PHYS
JI Can. J. Phys.
PD MAY
PY 2009
VL 87
IS 5
BP 469
EP 484
DI 10.1139/P08-130
PG 16
WC Physics, Multidisciplinary
SC Physics
GA 494RV
UT WOS:000269834000007
ER
PT J
AU Benner, DC
Miller, CE
Devi, VM
AF Benner, D. Chris
Miller, C. E.
Devi, V. Malathy
TI Constrained multispectrum analysis of CO2-Ar broadening at 6227 and 6348
cm(-1)
SO CANADIAN JOURNAL OF PHYSICS
LA English
DT Article
ID MOLECULAR SPECTROSCOPIC DATABASE; ANGULAR-MOMENTUM RELAXATION;
POTENTIAL-ENERGY SURFACES; CARBON-DIOXIDE; PERTURBER DEPENDENCIES; SPEED
DEPENDENCE; INFRARED-SPECTRA; CROSS-SECTIONS; DIFFERENT TEMPERATURES;
NITROUS-OXIDE
AB We report the first extensive experimental measurements of Ar-broadened half-width and pressure-induced shift coefficients, speed dependence parameters, and line mixing coefficients for the 30013 <- 00001 and 30012 <- 00001 bands of (OCO)-O-16-C-12-O-16 centered near 6227 and 6348 cm(-1), respectively. These parameters were determined from 15 self-broadened and six Ar-broadened CO2 spectra recorded at room temperature with long absorption path lengths (25 to 121 m) using the McMath-Pierce Fourier transform spectrometer (FTS) at the National Solar Observatory. All 21 spectra were fit simultaneously using a multispectrum nonlinear least-squares technique. The line positions and line intensities were constrained to quantum mechanical expressions to obtain maximum accuracies in the retrieved parameters. Speed-dependent line shapes with line mixing (via the relaxation matrix formalism) were required to remove systematic errors in the fit residuals using only the Voigt profile. Remaining fit residuals were minimized by adjusting the half-width and pressure-induced shift coefficients of the overlapping 31113 <- 01101 and 31112 <- 01101 hot bands. We compare the Ar-broadening parameters with those recently determined for self-and air-broadening in the 30012 <- 00001 and 30013/ 00001 bands and also with other Ar-broadening values from the literature, as appropriate.
C1 [Benner, D. Chris; Devi, V. Malathy] Coll William & Mary, Williamsburg, VA 23187 USA.
[Miller, C. E.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
RP Benner, DC (reprint author), Coll William & Mary, Box 8795, Williamsburg, VA 23187 USA.
EM dcbenn@wm.edu
FU National Science Foundation [ATM-0338475]
FX The material presented in this investigation is based upon work
supported by the National Science Foundation under Grant No. ATM-0338475
to the College of William and Mary. The research at the Jet Propulsion
Laboratory (JPL), California Institute of Technology, was performed
under contract with National Aeronautics and Space Administration. The
authors express sincere appreciation to M. Dulick of NOAO (National
Optical Astronomy Observatory) for the assistance in obtaining the data.
The authors thank NASA's Upper Atmosphere Research Program for support
of the McMath-Pierce laboratory facility.
NR 36
TC 8
Z9 7
U1 0
U2 6
PU CANADIAN SCIENCE PUBLISHING, NRC RESEARCH PRESS
PI OTTAWA
PA 1200 MONTREAL ROAD, BUILDING M-55, OTTAWA, ON K1A 0R6, CANADA
SN 0008-4204
J9 CAN J PHYS
JI Can. J. Phys.
PD MAY
PY 2009
VL 87
IS 5
BP 499
EP 515
DI 10.1139/P09-014
PG 17
WC Physics, Multidisciplinary
SC Physics
GA 494RV
UT WOS:000269834000009
ER
PT J
AU Predoi-Cross, A
McKellar, ARW
Benner, DC
Devi, VM
Gamache, RR
Miller, CE
Toth, RA
Brown, LR
AF Predoi-Cross, A.
McKellar, A. R. W.
Benner, D. Chris
Devi, V. Malathy
Gamache, R. R.
Miller, C. E.
Toth, R. A.
Brown, L. R.
TI Temperature dependences for air-broadened Lorentz half-width and
pressure shift coefficients in the 30013 <- 00001 and 30012 <- 00001
bands of CO2 near 1600 nm
SO CANADIAN JOURNAL OF PHYSICS
LA English
DT Article
ID DIODE-LASER MEASUREMENTS; CONSTRAINED MULTISPECTRUM ANALYSIS; SPEED
DEPENDENCE; LINE-SHAPES; IR LINES; MU-M; INTENSITIES; CM(-1);
TRANSITIONS; H2O
AB In this study, 39 high-resolution spectra of pure and air-broadened CO2 recorded at temperatures between 215 and 294 K were analyzed using a multispectrum nonlinear least-squares technique to determine temperature dependences of air-broadened Lorentz half-width and air-induced pressure shift coefficients for over 100 individual (CO2)-C-12-O-16 transitions in the 30012 <- 00001 (at 6348 cm(-1)) and 30013 <- 00001 (at 6228 cm(-1)) bands. Data were recorded with two different Fourier transform spectrometers (Kitt Peak FTS at the National Solar Observatory in Arizona and the Bomem FTS at NRC, Ottawa), with absorption path lengths ranging between 25 and 121 m. The sample pressures varied between 11 torr (pure CO2) and 924 torr (CO2-air) with volume mixing ratios of CO2 in air between similar to 1.5% and 11% (1 torr = 133.322 4 Pa). To minimize systematic errors and increase the accuracy of the retrieved parameters, a constrained multispectrum nonlinear least-squares fitting technique was used to include theoretical quantum mechanical expressions for the rovibrational energies and intensity parameters rather than retrieving the individual positions and intensities line by line. The results suggest no detectable vibrational dependence for the temperature dependences for the air-broadened Lorentz half-width coefficients and the air-induced pressure shift coefficients. The half-width coefficients and temperature dependence exponents were modeled using semiclassical calculations based upon the Robert-Bonamy formalism. A good agreement is seen between the measurements and theoretical calculations. Beyond |m| = 26, a simple scaling factor (0.96) has been applied to the calculated half-width coefficients to match the experimental measurements.
C1 [Predoi-Cross, A.] Univ Lethbridge, Dept Phys & Astron, Lethbridge, AB T1K 3M4, Canada.
[McKellar, A. R. W.] Natl Res Council Canada, Steacie Inst Mol Sci, Ottawa, ON K1A 0R6, Canada.
[Benner, D. Chris; Devi, V. Malathy] Coll William & Mary, Williamsburg, VA 23187 USA.
[Gamache, R. R.] Univ Massachusetts, Dept Environm Earth & Atmospher Sci, Lowell, MA 01854 USA.
[Miller, C. E.; Toth, R. A.; Brown, L. R.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
RP Predoi-Cross, A (reprint author), Univ Lethbridge, Dept Phys & Astron, Lethbridge, AB T1K 3M4, Canada.
EM adriana.predoicross@uleth.ca
FU National Sciences and Engineering Research Council of Canada (NSERC);
The research at the Jet Propulsion Laboratory (JPL); California
Institute of Technology; National Aeronautics and Space Administration;
National Science Foundation [ATM-0338475, ATM-0803135]
FX A. Predoi-Cross and A. R. W. Mckellar are grateful for financial support
from the National Sciences and Engineering Research Council of Canada
(NSERC). The research at the Jet Propulsion Laboratory (JPL), California
Institute of Technology, was performed under contract with National
Aeronautics and Space Administration. The support received from the
National Science Foundation under Grant No. ATM-0338475 to the College
of William and Mary is greatly appreciated. R. R. Gamache is pleased to
acknowledge support of this research by the National Science Foundation
through Grant No. ATM-0803135. The authors thank Mike Dulick of the
National Solar Observatory for his assistance in obtaining the data
recorded at Kitt Peak.
NR 38
TC 33
Z9 34
U1 0
U2 10
PU CANADIAN SCIENCE PUBLISHING, NRC RESEARCH PRESS
PI OTTAWA
PA 1200 MONTREAL ROAD, BUILDING M-55, OTTAWA, ON K1A 0R6, CANADA
SN 0008-4204
J9 CAN J PHYS
JI Can. J. Phys.
PD MAY
PY 2009
VL 87
IS 5
BP 517
EP 535
DI 10.1139/P08-137
PG 19
WC Physics, Multidisciplinary
SC Physics
GA 494RV
UT WOS:000269834000010
ER
PT J
AU Bloem, M
Alpcan, T
Basar, T
AF Bloem, Michael
Alpcan, Tansu
Basar, Tamer
TI Optimal and robust epidemic response for multiple networks
SO CONTROL ENGINEERING PRACTICE
LA English
DT Article; Proceedings Paper
CT 46th IEEE Conference on Decision and Control
CY DEC 12-14, 2007
CL New Orleans, LA
SP IEEE Control Syst Soc, United Technol, Springer, Wiley Blackwell, Taylor & Francis, Princeton Univ Press, Maplesoft, Siam
DE Epidemic response; Optimal control; LQR; H-infinity robust control
AB This paper studies the optimization of malicious software removal or patch deployment processes across multiple networks. The well-known classical epidemic model is adapted to model malware propagation in this multi-network framework. The trade-off between the infection spread and the patching costs is captured in a cost function, leading to an optimal control problem. In the single network case the optimal feedback controller is found by solving an associated Hamilton-Jacobi-Bell-man equation. This control law is numerically compared to the proportional response strategy typically assumed by the epidemic model. In the higher dimensional multiple-networks case, the system is linearized to derive feedback controllers using pole-placement, linear quadratic regulator (LQR) optimal control, and H-infinity optimal control, where the measurement errors in the number of infected clients are explicitly modeled. The resulting patching strategies are analyzed numerically and their results are compared. (c) 2007 Elsevier Ltd. All rights reserved.
C1 [Alpcan, Tansu] Deutsch Telekom Labs T Labs, D-10587 Berlin, Germany.
[Bloem, Michael] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA.
[Basar, Tamer] Univ Illinois, Coordinated Sci Lab, Urbana, IL 61801 USA.
RP Alpcan, T (reprint author), Deutsch Telekom Labs T Labs, D-10587 Berlin, Germany.
EM michael.bloem@nasa.gov; tansu.alpcan@telekom.de;
tbasar@control.csl.uiuc.edu
RI Alpcan, Tansu/D-7089-2014
OI Alpcan, Tansu/0000-0002-7434-3239
NR 19
TC 12
Z9 12
U1 0
U2 3
PU PERGAMON-ELSEVIER SCIENCE LTD
PI OXFORD
PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND
SN 0967-0661
EI 1873-6939
J9 CONTROL ENG PRACT
JI Control Eng. Practice
PD MAY
PY 2009
VL 17
IS 5
BP 525
EP 533
DI 10.1016/j.conengprac.2008.10.007
PG 9
WC Automation & Control Systems; Engineering, Electrical & Electronic
SC Automation & Control Systems; Engineering
GA 440RZ
UT WOS:000265718700001
ER
PT J
AU Batki, SL
Canfield, KM
Smyth, E
Ploutz-Snyder, R
AF Batki, Steven L.
Canfield, Kelly M.
Smyth, Emily
Ploutz-Snyder, Robert
TI Health-related quality of life in methadone maintenance patients with
untreated hepatitis C virus infection
SO DRUG AND ALCOHOL DEPENDENCE
LA English
DT Article
DE Hepatitis C; Methadone; Opioid; Substance abuse; Quality of life;
Health; Psychiatry
ID INJECTION-DRUG USERS; RISK-FACTORS; SURVEY QUESTIONNAIRE; HCV-INFECTION;
PREVALENCE; DEPRESSION; INTERFERON-ALPHA-2B; MANAGEMENT; REDUCTION;
EQUIPMENT
AB Objective: To assess health-related quality of life (HRQOL) in methadone maintenance treatment (MMT) patients with untreated chronic HCV infection and to determine the clinical factors that predict HRQOL.
Method: HRQOL was measured in 100 MMT patients entering an HCV treatment trial. Subjects were mostly male (61%) and white (81%) with a mean age of 43 (+/- 10). 57% had a current non-substance use psychiatric disorder. 55% had a current (past 12 months) substance use disorder, including 44% with current opioid or cocaine abuse/dependence. HRQOL in our sample was compared to published reports for the general population as well as for non-MMT HCV patients. To assess predictors of SF-36 HRQOL, hierarchical multiple regression techniques were used to assess model improvement with four blocks of baseline predictors: Demographics, Medical Severity, Addiction Severity, and Depression Severity.
Results: HRQOL scores were significantly lower than scores for the general population and were also lower than scores reported for untreated HCV patients not in MMT. Regression analysis demonstrated a consistent pattern whereby Depression Severity increased predictive accuracy for HRQOL measures over simpler models. Beck Depression Inventory scores significantly predicted quality of life across both the mental and physical composite scores and all eight sub-scales of the SF-36.
Conclusions: Untreated HCV patients in MMT had lower HRQOL than HCV patients not in MMT. Depression Severity was associated with significantly lower quality of life measures, suggesting that psychiatric evaluation and intervention prior to the start of HCV treatment may improve overall quality of life and could influence HCV treatment outcomes in MMT patients. (C) Published by Elsevier Ireland Ltd.
C1 [Batki, Steven L.] Univ Calif San Francisco, San Francisco VA Med Ctr, Dept Psychiat, Addict Psychiat Res Program, San Francisco, CA 94121 USA.
[Canfield, Kelly M.; Smyth, Emily] SUNY Upstate Med Univ, Dept Psychiat, Syracuse, NY 13210 USA.
[Ploutz-Snyder, Robert] Univ Space Res Assoc, NASA JSC, Lyndon B Johnson Space Ctr, SK, Houston, TX 77058 USA.
RP Batki, SL (reprint author), Univ Calif San Francisco, San Francisco VA Med Ctr, Dept Psychiat, Addict Psychiat Res Program, 4150 Clement St,116P, San Francisco, CA 94121 USA.
EM steven.batki@ucsf.edu
FU National Institute on Drug Abuse (NIDA) [R01 DA 016764]
FX This work was supported by National Institute on Drug Abuse (NIDA) grant
R01 DA 016764. NIDA had no further role in study design; in the
collection, analysis, and interpretation of the data; in the writing of
this report; and in the decision to Submit the paper for publication.
NR 48
TC 11
Z9 11
U1 4
U2 8
PU ELSEVIER IRELAND LTD
PI CLARE
PA ELSEVIER HOUSE, BROOKVALE PLAZA, EAST PARK SHANNON, CO, CLARE, 00000,
IRELAND
SN 0376-8716
J9 DRUG ALCOHOL DEPEN
JI Drug Alcohol Depend.
PD MAY 1
PY 2009
VL 101
IS 3
BP 176
EP 182
DI 10.1016/j.drugalcdep.2008.12.012
PG 7
WC Substance Abuse; Psychiatry
SC Substance Abuse; Psychiatry
GA 430PY
UT WOS:000265002200006
PM 19233573
ER
PT J
AU Newman, JA
Willard, SA
Smith, SW
Piascik, RS
AF Newman, John A.
Willard, Scott A.
Smith, Stephen W.
Piascik, Robert S.
TI Replica-based crack inspection
SO ENGINEERING FRACTURE MECHANICS
LA English
DT Article
DE Surface replica; Crack inspection; Small crack; Inconel 718
AB Surface replication has been proposed as a method for crack detection in space-shuttle main engine flowliner slots. The results of a feasibility study show that examination of surface replicas with a scanning electron microscope can result in the detection of cracks as small as 0.005 inch, and surface flaws as small as 0.001 inch, for the flowliner material. Published by Elsevier Ltd.
C1 [Newman, John A.; Smith, Stephen W.; Piascik, Robert S.] NASA, Langley Res Ctr, Hampton, VA 23681 USA.
[Willard, Scott A.] Lockheed Martin Space Operat, Langley Res Ctr, Hampton, VA 23681 USA.
RP Newman, JA (reprint author), NASA, Langley Res Ctr, MS 188E, Hampton, VA 23681 USA.
EM john.a.newman@nasa.gov
NR 6
TC 7
Z9 8
U1 0
U2 3
PU PERGAMON-ELSEVIER SCIENCE LTD
PI OXFORD
PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND
SN 0013-7944
J9 ENG FRACT MECH
JI Eng. Fract. Mech.
PD MAY
PY 2009
VL 76
IS 7
BP 898
EP 910
DI 10.1016/j.engfracmech.2008.12.012
PG 13
WC Mechanics
SC Mechanics
GA 453QX
UT WOS:000266627100006
ER
PT J
AU Preston, CM
Marin, R
Jensen, SD
Feldman, J
Birch, JM
Massion, EI
DeLong, EF
Suzuki, M
Wheeler, K
Scholin, CA
AF Preston, Christina M.
Marin, Roman, III
Jensen, Scott D.
Feldman, Jason
Birch, James M.
Massion, Eugene I.
DeLong, Edward F.
Suzuki, Marcelino
Wheeler, Kevin
Scholin, Christopher A.
TI Near real-time, autonomous detection of marine bacterioplankton on a
coastal mooring in Monterey Bay, California, using rRNA-targeted DNA
probes
SO ENVIRONMENTAL MICROBIOLOGY
LA English
DT Article
ID DINOFLAGELLATE KARENIA-BREVIS; OLIGONUCLEOTIDE MICROARRAYS;
HYBRIDIZATION FORMATS; MICROBIAL-POPULATIONS; QUANTITATIVE-ANALYSIS;
INVERTEBRATE LARVAE; MOLECULAR-DETECTION; FLOW CYTOMETER; BACTERIA;
PHYTOPLANKTON
AB A sandwich hybridization assay (SHA) was developed to detect 16S rRNAs indicative of phylogenetically distinct groups of marine bacterioplankton in a 96-well plate format as well as low-density arrays printed on a membrane support. The arrays were used in a field-deployable instrument, the Environmental Sample Processor (ESP). The SHA employs a chaotropic buffer for both cell homogenization and hybridization, thus target sequences are captured directly from crude homogenates. Capture probes for seven of nine different bacterioplankton clades examined reacted specifically when challenged with target and non-target 16S rRNAs derived from in vitro transcribed 16S rRNA genes cloned from natural samples. Detection limits were between 0.10-1.98 and 4.43- 12.54 fmole ml(-1) homogenate for the 96-well plate and array SHA respectively. Arrays printed with five of the bacterioplankton-specific capture probes were deployed on the ESP in Monterey Bay, CA, twice in 2006 for a total of 25 days and also utilized in a laboratory time series study. Groups detected included marine alphaproteobacteria, SAR11, marine cyanobacteria, marine group I crenarchaea, and marine group II euryarchaea. To our knowledge this represents the first report of remote in situ DNA probe-based detection of marine bacterioplankton.
C1 [Preston, Christina M.; Marin, Roman, III; Jensen, Scott D.; Feldman, Jason; Birch, James M.; Massion, Eugene I.; Wheeler, Kevin; Scholin, Christopher A.] Monterey Bay Aquarium Res Inst, Moss Landing, CA 95039 USA.
[Feldman, Jason] CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA.
[DeLong, Edward F.] MIT, Dept Civil & Environm Engn, Cambridge, MA 02139 USA.
[DeLong, Edward F.] MIT, Div Biol Engn, Cambridge, MA 02139 USA.
[Suzuki, Marcelino] Univ Maryland, Chesapeake Biol Lab, Solomons, MD 20668 USA.
[Wheeler, Kevin] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA.
RP Preston, CM (reprint author), Monterey Bay Aquarium Res Inst, Moss Landing, CA 95039 USA.
EM preston@mbari.org
RI Suzuki, Marcelino/D-3329-2009
OI Suzuki, Marcelino/0000-0003-3868-6362
FU David and Lucille Packard Foundation; Keck Foundation; NSF Microbial
Observatory; Gordon and Betty Moore Foundation
FX We are grateful for the expertise and work of the engineers, technicians
and machinists at MBARI for maintaining the instrument. We thank J. Zehr
for providing the Synechococcus culture, V. Orphan for providing the
group III euryarchaeal plasmid 1#6, and three anonymous reviewers for
their editorial comments. We also thank the Moss Landing Marine
Laboratories Small Boats Operation and the captains and crews of the R/V
Zephyr. This work was supported in part by grants from the David and
Lucille Packard Foundation to C.A.S., Keck Foundation to E.F.D. and
C.A.S., NSF Microbial Observatory grant to E.F.D. and Gordon and Betty
Moore Foundation grant to C.A.S and E.F.D.
NR 50
TC 36
Z9 36
U1 0
U2 10
PU WILEY-BLACKWELL PUBLISHING, INC
PI MALDEN
PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA
SN 1462-2912
J9 ENVIRON MICROBIOL
JI Environ. Microbiol.
PD MAY
PY 2009
VL 11
IS 5
BP 1168
EP 1180
DI 10.1111/j.1462-2920.2009.01848.x
PG 13
WC Microbiology
SC Microbiology
GA 437IW
UT WOS:000265481600012
PM 19210704
ER
PT J
AU Bissaldi, E
von Kienlin, A
Lichti, G
Steinle, H
Bhat, PN
Briggs, MS
Fishman, GJ
Hoover, AS
Kippen, RM
Krumrey, M
Gerlach, M
Connaughton, V
Diehl, R
Greiner, J
van der Horst, AJ
Kouveliotou, C
McBreen, S
Meegan, CA
Paciesas, WS
Preece, RD
Wilson-Hodge, CA
AF Bissaldi, E.
von Kienlin, A.
Lichti, G.
Steinle, H.
Bhat, P. N.
Briggs, M. S.
Fishman, G. J.
Hoover, A. S.
Kippen, R. M.
Krumrey, M.
Gerlach, M.
Connaughton, V.
Diehl, R.
Greiner, J.
van der Horst, A. J.
Kouveliotou, C.
McBreen, S.
Meegan, C. A.
Paciesas, W. S.
Preece, R. D.
Wilson-Hodge, C. A.
TI Ground-based calibration and characterization of the Fermi gamma-ray
burst monitor detectors
SO EXPERIMENTAL ASTRONOMY
LA English
DT Article
DE Fermi Gamma-Ray space telescope; GLAST; Gamma-Ray detectors;
Calibration; NaI(Tl); BGO; Gamma-Ray burst
ID HIGH-ENERGY; SPECTRAL PROPERTIES; BESSY-II; GLAST; SIMULATION; NAI(T1);
BAMLINE; EGRET
AB One of the scientific objectives of NASA's Fermi Gamma-ray Space Telescope is the study of Gamma-Ray Bursts (GRBs). The Fermi Gamma-Ray Burst Monitor (GBM) was designed to detect and localize bursts for the Fermi mission. By means of an array of 12 NaI(Tl) (8 keV to 1 MeV) and two BGO (0.2 to 40 MeV) scintillation detectors, GBM extends the energy range (20 MeV to > 300 GeV) of Fermi's main instrument, the Large Area Telescope, into the traditional range of current GRB databases. The physical detector response of the GBM instrument to GRBs is determined with the help of Monte Carlo simulations, which are supported and verified by on-ground individual detector calibration measurements. We present the principal instrument properties, which have been determined as a function of energy and angle, including the channel-energy relation, the energy resolution, the effective area and the spatial homogeneity.
C1 [Bissaldi, E.; von Kienlin, A.; Lichti, G.; Steinle, H.; Diehl, R.; Greiner, J.; McBreen, S.] Max Planck Inst Extraterr Phys, D-85748 Garching, Germany.
[Bhat, P. N.; Briggs, M. S.; Connaughton, V.; Paciesas, W. S.; Preece, R. D.] Univ Alabama, NSSTC, Huntsville, AL 35899 USA.
[Fishman, G. J.; van der Horst, A. J.; Kouveliotou, C.; Meegan, C. A.; Wilson-Hodge, C. A.] NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA.
[Hoover, A. S.; Kippen, R. M.] Los Alamos Natl Lab, Los Alamos, NM USA.
[Krumrey, M.; Gerlach, M.] Phys Tech Bundesanstalt, Berlin, Germany.
RP Bissaldi, E (reprint author), Max Planck Inst Extraterr Phys, Giessenbachstr 1, D-85748 Garching, Germany.
EM ebs@mpe.mpg.de
RI Krumrey, Michael/G-6295-2011; Bissaldi, Elisabetta/K-7911-2016;
OI Bissaldi, Elisabetta/0000-0001-9935-8106; Preece,
Robert/0000-0003-1626-7335
NR 35
TC 27
Z9 27
U1 1
U2 7
PU SPRINGER
PI DORDRECHT
PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS
SN 0922-6435
EI 1572-9508
J9 EXP ASTRON
JI Exp. Astron.
PD MAY
PY 2009
VL 24
IS 1-3
BP 47
EP 88
DI 10.1007/s10686-008-9135-4
PG 42
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 437SX
UT WOS:000265508300003
ER
PT J
AU Hulot, G
Olsen, N
Thebault, E
Hemant, K
AF Hulot, Gauthier
Olsen, Nils
Thebault, Erwan
Hemant, Kumar
TI Crustal concealing of small-scale core-field secular variation
SO GEOPHYSICAL JOURNAL INTERNATIONAL
LA English
DT Article
DE Dynamo: theories and simulations; Magnetic anomalies: modelling and
interpretation; Satellite magnetics
ID EARTHS MAGNETIC-FIELD; GEOMAGNETIC-FIELD; SATELLITE DATA; REMANENT
MAGNETIZATION; CHAMP; MODEL; SURFACE; SWARM; FLOWS; CONSTELLATION
AB The Earth's magnetic field is mainly produced within the Earth's liquid and electrically conducting core, as a result of a process known as the geodynamo. Many other sources also contribute to the magnetic signal accessible to observation at the Earth's surface, partly obscuring the main core magnetic field signal. Thanks to a series of very successful satellites and to advances in magnetic field modelling techniques, considerable progress has, however, been made in the recent years toward better identifying the signal of each of these sources. In particular, temporal changes in the field of internal origin happen to be detectable now in spherical harmonic degrees up to, perhaps, 16. All of these changes are usually attributed to changes in the core field itself, the secular variation, on the ground that the lithospheric magnetization cannot produce such signals. It has, however, been pointed out, on empirical grounds, that temporal changes in the field of internal origin produced by the induced part of the lithospheric magnetization could dominate the core field signal beyond degree 22. This short note revisits this issue by taking advantage of our improved knowledge of the small-scale field changes and of the likely sources of the lithospheric field. We rely on a simple extrapolation of the observed spatial spectrum of the field changes beyond degree 16 and use a forward approach based on a recent geological model of lithospheric magnetization. This leads us to confirm that the main cause of the observed changes in the field of internal origin up to some critical degree, N(C), is indeed likely to be the secular variation of the core field, but that the signal produced by the time-varying lithospheric field is bound to dominate and conceal the time-varying core signal beyond that critical degree, in very much the same way the permanent component of the lithospheric field dominates and conceals the permanent component of the core field beyond degree 14. All uncertainties taken into account, we estimate N(C) to lie between 22 and 24. We, however, also note that in practice, the main limitation to the observation of the core field small-scale secular variation is not so much its concealing by the field of lithospheric origin but its fast changing nature and small magnitude. This leads us to conclude that whereas cumulative small-scale lithospheric field changes might be detected some day, detection of core-field secular variation beyond degree 18 is likely to remain a severe challenge for some time.
C1 [Hulot, Gauthier; Thebault, Erwan] Univ Paris Diderot, Equipe Geomagnetisme, Inst Phys Globe Paris, CNRS,INSU, F-75252 Paris, France.
[Olsen, Nils] Univ Copenhagen, DTU Space, DK-2100 Copenhagen, Denmark.
[Olsen, Nils] Univ Copenhagen, Niels Bohr Inst, DK-2100 Copenhagen, Denmark.
[Hemant, Kumar] NASA, Goddard Space Flight Ctr, ORAU, Planetary Geodynam Lab, Greenbelt, MD 20771 USA.
RP Hulot, G (reprint author), Univ Paris Diderot, Equipe Geomagnetisme, Inst Phys Globe Paris, CNRS,INSU, 4 Pl Jussieu, F-75252 Paris, France.
EM gh@ipgp.jussieu.fr
RI Hulot, Gauthier/A-5627-2011; Olsen, Nils/H-1822-2011; Thebault,
Erwan/A-5670-2011
OI Olsen, Nils/0000-0003-1132-6113;
FU CNES
FX Helpful comments by two anonymous reviewers are gratefully acknowledged.
This study was partly supported by CNES. This is IPGP contribution no.
2480.
NR 45
TC 14
Z9 18
U1 0
U2 2
PU WILEY-BLACKWELL PUBLISHING, INC
PI MALDEN
PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA
SN 0956-540X
J9 GEOPHYS J INT
JI Geophys. J. Int.
PD MAY
PY 2009
VL 177
IS 2
BP 361
EP 366
DI 10.1111/j.1365-246X.2009.04119.x
PG 6
WC Geochemistry & Geophysics
SC Geochemistry & Geophysics
GA 430TR
UT WOS:000265012200004
ER
PT J
AU Huang, CQ
Kim, S
Song, K
Townshend, JRG
Davis, P
Altstatt, A
Rodas, O
Yanosky, A
Clay, R
Tucker, CJ
Musinsky, J
AF Huang, Chengquan
Kim, Sunghee
Song, Kuan
Townshend, John R. G.
Davis, Paul
Altstatt, Alice
Rodas, Oscar
Yanosky, Alberto
Clay, Rob
Tucker, Compton J.
Musinsky, John
TI Assessment of Paraguay's forest cover change using Landsat observations
SO GLOBAL AND PLANETARY CHANGE
LA English
DT Article; Proceedings Paper
CT Fall Annual Meeting of the American-Geophysical-Union
CY 2005
CL San Francisco, CA
SP Amer Geophys Union
DE Atlantic forest; Chaco Woodland; forest loss; protected area; Landsat;
Paraguay
ID PROTECTED AREAS; TROPICAL DEFORESTATION; CONSERVATION; BIODIVERSITY;
REGROWTH; AMAZON; AVHRR; MODEL; CHACO
AB Comprehensive assessments of Paraguay's forest cover (FC) change from the 1970s to the 2000s using Landsat observations were conducted, including a wall-to-wall mapping of changes across the whole country between the 1990s and 2000s, and an assessment of forest area in the Atlantic Forest ecoregion in the 1970s using a systematic sampling approach. The derived wall-to-wall FC change map was evaluated using available high resolution satellite images and aerial photos. The overall accuracy values were 92% or higher in the areas covered by those high resolution data sets. The results revealed that the Atlantic Forest ecoregion experienced the most forest loss, with the 73.4% forest cover in the 1970s decreasing precipitously down to 40.7% by the 1990s and further down to 24.9% by the 2000s. The rapid loss of Atlantic forests was driven by complex social economic forces, including widespread land disputes arising from long time inequalities and profits from exporting agricultural products. Forest changes in the Humid Chaco and the Chaco ecoregions were relatively moderate. However, extensive forests were converted to non-forest land use near a major population center. The results also revealed that so far the established protected areas were effective in protecting forest within their border. However, most of the forests surrounding the protected areas were lost by the 2000s. Loss of Atlantic forest is a major threat to the rich biodiversity found in this region. The alarming deforestation rates over the last three decades and the low percentage of Atlantic forest left by the 2000s call for immediate actions to halt the trends of forest loss. (C) 2009 Elsevier B.V. All rights reserved.
C1 [Huang, Chengquan; Song, Kuan; Townshend, John R. G.; Davis, Paul; Altstatt, Alice; Tucker, Compton J.] Univ Maryland, Dept Geog, College Pk, MD 20742 USA.
[Kim, Sunghee; Song, Kuan; Davis, Paul] Univ Maryland, Inst Adv Comp Studies, College Pk, MD 20742 USA.
[Tucker, Compton J.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
[Musinsky, John] Conservat Int, Washington, DC 20036 USA.
RP Huang, CQ (reprint author), Univ Maryland, Dept Geog, 2181 LeFrak Hall, College Pk, MD 20742 USA.
EM cqhuang@umd.edu; sunghee@wam.umd.edu
OI Huang, Chengquan/0000-0003-0055-9798
NR 54
TC 51
Z9 59
U1 2
U2 25
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0921-8181
EI 1872-6364
J9 GLOBAL PLANET CHANGE
JI Glob. Planet. Change
PD MAY
PY 2009
VL 67
IS 1-2
SI SI
BP 1
EP 12
DI 10.1016/j.gloplacha.2008.12.009
PG 12
WC Geography, Physical; Geosciences, Multidisciplinary
SC Physical Geography; Geology
GA 455JC
UT WOS:000266754000002
ER
PT J
AU Melchiorri, R
Encrenaz, T
Drossart, P
Fouchet, T
Forget, F
Titov, D
Maltagliati, L
Altieri, F
Vincendon, M
Langevin, Y
Bibring, JP
AF Melchiorri, R.
Encrenaz, T.
Drossart, P.
Fouchet, T.
Forget, F.
Titov, D.
Maltagliati, L.
Altieri, F.
Vincendon, M.
Langevin, Y.
Bibring, J. P.
TI OMEGA/Mars Express: South Pole Region, water vapor daily variability
SO ICARUS
LA English
DT Article
DE Mars, atmosphere; Mars, polar caps; Spectroscopy
ID MARTIAN ATMOSPHERE; THARSIS VOLCANOS; MARS; CYCLE; SURFACE;
SPECTROMETER; AEROSOLS; DEPOSITS; MODEL
AB Polar regions on Mars are the Most Suitable places to observe water vapor daily variability because in,any observation crossing the Pole we can observe very different local time and because the poles are considered to be the main permanent and seasonal water reservoir of the planet. We report on a daily variability of water vapor in the South Pole Region (SPR), observed by OMEGA/Mars Express during the South spring-summer period (Ls similar to 250 degrees-270 degrees) outside the CO(2) ice cap, that has never been observed before by other instruments. We have been able to estimate an increase of few precipitable microns during the day. A possible scenario includes the presence of regolith, or another component that could gather water front the atmosphere, adsorbing the water into the surface during the night time and desorbing it as soon as the Sun reaches sufficient height to heat the ground. This hypothesis is even more plausible considering the presence of observed local enhancements in the morning sections associated with the illumination of the Sun and the total absence in the data for water ice. (c) 2008 Elsevier Inc. All rights reserved.
C1 [Melchiorri, R.] NASA, Ames Res Ctr, ORAU NASA Postdoctoral Program, Moffett Field, CA 94035 USA.
[Melchiorri, R.; Encrenaz, T.; Drossart, P.; Fouchet, T.] Observ Paris, LESIA, Sect Meudon, Paris, France.
[Forget, F.] Lab Metheorol Dynam, Paris, France.
[Titov, D.; Maltagliati, L.] Max Planck Inst Solar Syst Res, Katlenburg Lindau, Germany.
[Altieri, F.] Ist Fis Spazio & Mezzo Interstellare, Rome, Italy.
[Vincendon, M.; Langevin, Y.; Bibring, J. P.] Inst Astrophys Spatiale, Orsay, France.
RP Melchiorri, R (reprint author), NASA, Ames Res Ctr, ORAU NASA Postdoctoral Program, MS 245-3, Moffett Field, CA 94035 USA.
EM riccardo.melchiorri-1@nasa.gov
RI Fouchet, Thierry/C-6374-2017
OI Fouchet, Thierry/0000-0001-9040-8285
FU NASA/Ames Research Center
FX This research was supported also by all appointment to the NASA
Postdoctoral Program at the NASA/Ames Research Center administered by
Oak Ridge Associated Universities through a contract with NASA.
NR 32
TC 11
Z9 11
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
J9 ICARUS
JI Icarus
PD MAY
PY 2009
VL 201
IS 1
BP 102
EP 112
DI 10.1016/j.icarus.2008.12.018
PG 11
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 444CM
UT WOS:000265957900007
ER
PT J
AU Brozovic, M
Ostro, SJ
Benner, LAM
Giorgini, JD
Jurgens, RF
Rose, R
Nolan, MC
Hine, AA
Magri, C
Scheeres, DJ
Margot, JL
AF Brozovic, Marina
Ostro, Steven J.
Benner, Lance A. M.
Giorgini, Jon D.
Jurgens, Raymond F.
Rose, Randy
Nolan, Michael C.
Hine, Alice A.
Magri, Christopher
Scheeres, Daniel J.
Margot, Jean-Luc
TI Radar observations and a physical model of Asteroid 4660 Nereus, a prime
space mission target
SO ICARUS
LA English
DT Article
DE Radar observations; Asteroids
ID NEAR-EARTH ASTEROIDS; 33342 1998 WT24; ENSTATITE ACHONDRITE; DYNAMICAL
EVOLUTION; 1620 GEOGRAPHOS; 2867 STEINS; OBJECTS; POPULATION; ITOKAWA;
TORQUES
AB Near-Earth Asteroid 4660 Nereus has been identified as a potential spacecraft target since its 1982 discovery because of the low delta-V required for a spacecraft rendezvous. However. Surprisingly little is known about its physical characteristics. Here We report Arecibo (S-band, 2380-MHz, 13-cm) and Goldstone (X-band, 8560-MHz, 3.5-cm) radar observations of Nereus during its 2002 close approach. Analysis of an extensive dataset of delay-Doppler images and Continuous wave (CW) spectra yields a model that resembles an ellipsoid with principal axis dimensions X = 510 +/- 20 m, Y = 330 +/- 20 m and Z = 241(+80) m. The pole direction is approximately located at ecliptic pole longitude and latitude Of lambda = +25 degrees, beta = +80 degrees with the uncertainty radius of 10 degrees. Our modeling yields a refined rotation period of 15.16 +/- 0.04 h. Nereus has a circular polarization (SC/OC) ratio of 0.74 +/- 0.08, which implies Substantial near-surface centimeter-to-decimeter scale toughness. Dynamical analysis Of Our model suggests that YORP alteration of the rotation period may become evident within a few years. Nereus has two stable synchronous orbits where natural material may remain in orbit, while most asteroids observed to date do not have Such stable Synchronous orbits. We also find that spacecraft Orbits about Nereus are feasible. (c) 2009 Elsevier Inc. All rights reserved.
C1 [Brozovic, Marina; Ostro, Steven J.; Benner, Lance A. M.; Giorgini, Jon D.; Jurgens, Raymond F.; Rose, Randy] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
[Nolan, Michael C.; Hine, Alice A.] Natl Astron & Ionosphere Ctr, Arecibo Observ, Arecibo, PR 00613 USA.
[Magri, Christopher] Univ Maine, Farmington, ME 04938 USA.
[Scheeres, Daniel J.] Univ Colorado, Boulder, CO 80309 USA.
[Margot, Jean-Luc] Cornell Univ, Dept Astron, Ithaca, NY 14853 USA.
RP Brozovic, M (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA.
EM marina.brozovic@jpl.nasa.gov
RI Margot, Jean-Luc/A-6154-2012; Nolan, Michael/H-4980-2012
OI Margot, Jean-Luc/0000-0001-9798-1797; Nolan, Michael/0000-0001-8316-0680
FU National Aeronautics and Space Administration (NASA)
FX We thank the Arecibo and Goldstone technical and support staffs for help
with the radar observations. The Arecibo Observatory is part of the
National Astronomy and Ionosphere Center, which is operated by Cornell
University under a cooperative agreement with the National Science
Foundation (NSF) and, at the time of this experiment, also had support
from the National Aeronautics and Space Administration (NASA). We are
very much in debt to the reviewers, Bob Gaskell and in anonymous
reviewer whose comments significantly improved this paper. We would also
like to thank Michael W. Busch for useful discussion On SHAPE modeling.
Some of this work was performed at the jet Propulsion Laboratory,
California Institute of Technology, under contract with NASA. This
material is based in part upon work supported by NASA Under the Science
Mission Directorate Research and Analysis Programs.
NR 70
TC 9
Z9 10
U1 1
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 MAY
PY 2009
VL 201
IS 1
BP 153
EP 166
DI 10.1016/j.icarus.2008.12.029
PG 14
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 444CM
UT WOS:000265957900011
ER
PT J
AU Bellucci, A
Sicardy, B
Drossart, P
Rannou, P
Nicholson, PD
Hedman, M
Baines, KH
Burrati, B
AF Bellucci, A.
Sicardy, B.
Drossart, P.
Rannou, P.
Nicholson, P. D.
Hedman, M.
Baines, K. H.
Burrati, B.
TI Titan solar occultation observed by Cassini/VIMS: Gas absorption and
constraints on aerosol composition
SO ICARUS
LA English
DT Article
DE Titan; Occultations; Atmospheres, composition
ID DIFFUSE INTERSTELLAR-MEDIUM; MIXED VERTICAL PROFILE; CARBON-MONOXIDE;
SPECTROSCOPIC DATABASE; OPTICAL-CONSTANTS; X-RAY; ATMOSPHERE; CO; HAZE;
STRATOSPHERE
AB A solar occultation by Titan's atmosphere has been observed through the solar port of the Cassini/VIMS instrument on January 15th, 2006. Transmission spectra acquired during solar egress probe the atmosphere in the altitude range 70 to 900 kin at the latitude of 71 degrees S. Several molecular absorption bands of CH(4) and CO are visible in these data. A line-by-line radiative transfer calculation in spherical geometry is used to model three methane hands (1.7, 2.3, 3.3 mu m) and the CO 4.7 mu m hand. Above 200 kin, the methane 2.3 pin hand is well fit with constant mixing ratio between 1.4 and 1.7%, in agreement with in situ and other Cassini measurements. Under 200 km, there are discrepancies between models and observations that are yet fully understood. Under 480 km, the 3.3 mu m CH4 hand is mixed with a large and deep additional absorption. It corresponds to the C-H stretching mode of aliphatic hydrocarbon chains attached to large organic molecules. The CO 4.7 pin hand is observed in the lower stratosphere (altitudes below 150 km) and is well fit with a model with constant mixing ratio of 33 +/- 10 ppm. The Continuum level of the observed transmission spectra provides new constraints on the aerosol content of the atmosphere. A model using fractal aggregates and optical properties of tholins produced by Khare et al. [Khare, B.N., Sagan, C., Arakawa, E.T., Suits, F, Callcott, T.A., Williams, M.W., 1984. Icarus 60, 127-137] is developed. Fractal aggregates with more than 1000 spheres of radius 0.05 mu m are needed to fit the data. Clear differences in the chemical composition are revealed between tholins and actual haze particles. Extinction and density profiles are also retrieved using an inversion of the continuum values. An exponential increase of the haze number density is observed under 420 km with a typical scale height of 60 km. (c) 2009 Elsevier Inc. All rights reserved.
C1 [Bellucci, A.; Sicardy, B.; Drossart, P.] Univ Paris Diderot, Univ Paris 06, Observ Paris, Lab Etud Spatiales LESIA, F-92195 Meudon, France.
[Sicardy, B.] Inst Univ France, F-75005 Paris, France.
[Rannou, P.] Univ Reims, GSMA, UMR 6089, F-51687 Reims, France.
[Rannou, P.] Univ Versailles St Quentin, Serv Aeron, UMR 7620, F-91370 Verrieres Le Buisson, France.
[Nicholson, P. D.; Hedman, M.] Cornell Univ, Dept Astron, Ithaca, NY 14853 USA.
[Baines, K. H.; Burrati, B.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
RP Sicardy, B (reprint author), Univ Paris Diderot, Univ Paris 06, Observ Paris, Lab Etud Spatiales LESIA, 5 Pl Jules Janssen, F-92195 Meudon, France.
EM bruno.sicardy@obspm.fr
RI RANNOU, Pascal/I-9059-2012
FU Centre National d'Etudes Spatiales (CNES)
FX We thank the Centre National d'Etudes Spatiales (CNES) for Supporting
the VIMS data interpretation. We also thank B. Bezard and E. Lellouch
for their help in the validation of the radiative transfer code and for
the data interpretation.
NR 42
TC 51
Z9 51
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 0019-1035
J9 ICARUS
JI Icarus
PD MAY
PY 2009
VL 201
IS 1
BP 198
EP 216
DI 10.1016/j.icarus.2008.12.024
PG 19
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 444CM
UT WOS:000265957900016
ER
PT J
AU Barnes, JW
Brown, RH
Soderblom, JM
Soderblom, LA
Jaumann, R
Jackson, B
Le Mouelic, S
Sotin, C
Buratti, BJ
Pitman, KM
Baines, KH
Clark, RN
Nicholson, PD
Turtle, EP
Perry, J
AF Barnes, Jason W.
Brown, Robert H.
Soderblom, Jason M.
Soderblom, Laurence A.
Jaumann, Ralf
Jackson, Brian
Le Mouelic, Stephane
Sotin, Christophe
Buratti, Bonnie J.
Pitman, Karly M.
Baines, Kevin H.
Clark, Roger N.
Nicholson, Phillip D.
Turtle, Elizabeth P.
Perry, Jason
TI Shoreline features of Titan's Ontario Lacus from Cussini/VIMS
observations
SO ICARUS
LA English
DT Article
DE Titan
ID CASSINI RADAR; SURFACE; CLOUDS; ETHANE; OCEAN; LAKES; DIVERSITY; IMAGES;
DUNES; SEAS
AB We analyze observations of Titan's South polar lake Ontario Lacus obtained by Cassini's Visual and Infrared Mapping Spectrometer during the 38th flyby of Titan (T38: 2007 December 5). These near-closest-approach observations have the highest signal-to-noise, the finest spatial resolution, and the least atmospheric influence of any near-infrared lake observation to date. We use the large, spatially flat, and low-albedo interior of Ontario Lacus as a calibration target allowing LIS to derive ail analytical atmospheric correction for emission angle. The dark lake interior is surrounded by two separate annuli that follow the lake interior's Contours. The inner annulus is uniformly dark, but not so much as the interior lake, and is generally 5-10 kilometers wide at the lake's southeastern margin. We propose that it represents wet lakebed sediments exposed by either tidal sloshing of the lake or seasonal methane loss leading to lower lake-volume. the exterior annulus is bright and shows a spectrum consistent with a relatively low water-ice content relative to the rest of Titan. It may represent fine-grained condensate deposits from a past era of higher lake level. Together, the annuli seem to indicate that the lake level for Ontario Lacus has changed over time. This hypothesis can be tested with observations scheduled for future Titan flybys. (c) 2008 Elsevier Inc. All rights reserved.
C1 [Barnes, Jason W.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA.
[Barnes, Jason W.] Univ Idaho, Dept Phys, Moscow, ID 83844 USA.
[Brown, Robert H.; Soderblom, Jason M.; Jackson, Brian; Perry, Jason] Univ Arizona, Dept Planetary Sci, Tucson, AZ 85721 USA.
[Soderblom, Laurence A.] US Geol Survey, Flagstaff, AZ 86001 USA.
[Jaumann, Ralf] DLR, Inst Planetary Res, D-12489 Berlin, Germany.
[Le Mouelic, Stephane] Univ Nantes, CNRS, Lab Planetol & Geodynam, UMR6112, Nantes, France.
[Sotin, Christophe; Buratti, Bonnie J.; Pitman, Karly M.; Baines, Kevin H.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
[Clark, Roger N.] US Geol Survey, Denver, CO 80225 USA.
[Nicholson, Phillip D.] Cornell Univ, Dept Astron, Ithaca, NY 14853 USA.
[Turtle, Elizabeth P.] Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA.
RP Barnes, JW (reprint author), NASA, Ames Res Ctr, Mail Stop 244-30, Moffett Field, CA 94035 USA.
EM jason@barnesos.net
RI Barnes, Jason/B-1284-2009; Turtle, Elizabeth/K-8673-2012;
OI Barnes, Jason/0000-0002-7755-3530; Turtle,
Elizabeth/0000-0003-1423-5751; Soderblom, Jason/0000-0003-3715-6407
FU NASA Postdoctoral Program Fellowship at NASA Ames Research Center;
Cassini VIMS team
FX J.W.B. is supported by a NASA Postdoctoral Program Fellowship at NASA
Ames Research Center administrated by Oak Ridge Associated Universities.
J.W.B. also acknowledges support from the Cassini VIMS team. Thank you
to the 2008 LPL beaches field trip participants for their comments and
patience.
NR 35
TC 43
Z9 43
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 0019-1035
J9 ICARUS
JI Icarus
PD MAY
PY 2009
VL 201
IS 1
BP 217
EP 225
DI 10.1016/j.icarus.2008.12.028
PG 9
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 444CM
UT WOS:000265957900017
ER
PT J
AU Wiegert, P
Vaubaillon, J
Campbell-Brown, M
AF Wiegert, Paul
Vaubaillon, Jeremie
Campbell-Brown, Margaret
TI A dynamical model of the sporadic meteoroid complex
SO ICARUS
LA English
DT Article
DE Meteors; Comets; Asteroids; Interplanetary dust; Earth
ID VELOCITY DISTRIBUTION; HEAD-ECHOES; SOLAR-SYSTEM; HIGH-POWER; 2003 EH1;
RADAR; COMET; ORBIT; DISTRIBUTIONS; PARENT
AB Sporadic meteoroids are the most abundant yet least understood component of tire Earth's meteoroid complex. This paper aims to build a physics-based model of this complex calibrated with five years of radar observations. The model of the sporadic meteoroid complex presented here Includes the effects of the Sun and all eight planets, radiation forces and collisions. The model Uses the observed meteor patrol radar strengths of the sporadic meteors to solve for the dust production rates of the populations of cornets modeled, as well as the mass index. The model can explain sonic of the differences between the meteor velocity distributions seen by transverse versus radial scatter radars. The different ionization limits Of the two techniques result in their looking, at different populations with different velocity distributions. Radial scatter radars see primarily meteors from 55P/Tempel-Tuttle (or an orbitally similar lost comet), while transverse scatter radars are dominated by larger meteoroids from the Jupiter-family comets. In fact our results suggest that the sporadic complex is better understood as originating from a small number of cornets which transfer material to near-Earth space quite efficiently, rather than as a product of the cometary population as a whole. The model also sheds light on variations in the mass index reported by different radars, revealing it to be a result of their sampling different portions of the meteorois population. In addition, we find that a mass index of s = 2.34 as observed at Faith requires a shallower index (s = 2.2) at the time of meteoroid production because of size-dependent processes in the evolution of meteoroids. The model also reveals the origin of the 55 degrees radius ring seen centered on the Earth's apex (a result of high-inclination meteoroids undergoing Kozai oscillation) and the central condensations seen in the apex sources, as well as providing insight into the strength asymmetry of the helion and anti-helion sources. (c) 2009 Elsevier Inc. All rights reserved.
C1 [Wiegert, Paul; Campbell-Brown, Margaret] Univ Western Ontario, Dept Phys & Astron, London, ON, Canada.
[Vaubaillon, Jeremie] CALTECH, Jet Prop Lab, Spitzer Space Ctr, Pasadena, CA 91125 USA.
RP Wiegert, P (reprint author), Univ Western Ontario, Dept Phys & Astron, London, ON, Canada.
EM pwiegert@uwo.ca
FU NASA Meteoroid Environment Office; Natural Sciences and Engineering
Research Council of Canada
FX We thank David Asher and an anonymous referee for their through reviews
which much improved this work. This research was supported in part by
the NASA Meteoroid Environment Office and the Natural Sciences and
Engineering Research Council of Canada.
NR 48
TC 42
Z9 42
U1 1
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 MAY
PY 2009
VL 201
IS 1
BP 295
EP 310
DI 10.1016/j.icarus.2008.12.030
PG 16
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 444CM
UT WOS:000265957900022
ER
PT J
AU Smith, AW
Lissauer, JJ
AF Smith, Andrew W.
Lissauer, Jack J.
TI Orbital stability of systems of closely-spaced planets
SO ICARUS
LA English
DT Article
DE Planetary dynamics; Celestial mechanics; Extrasolar planets
ID PROTOPLANET SYSTEM; INSTABILITY; DYNAMICS
AB An investigation of the stability of systems of 1 M(circle plus) (Earth-mass) bodies orbiting a Sun-like star has been conducted for Virtual times reaching 10 billion years. For the majority of the tests, a symplectic integrator with a fixed timestep of between 1 and 10 clays was employed: however, smaller timesteps and a Bulirsch-Stoer integrator were also selectively utilized to increase confidence in the results. In most cases, the planets were started on initially coplanar, circular orbits, and the longitudinal initial positions of neighboring planets were widely separated. The ratio of the semimajor axes of consecutive planets in each system Was approximately uniform (so the spacing between consecutive planets increased slowly in terms of distance from the star). The stability time for a system was taken to be the time at which the orbits of two or more planets crossed. Our results show that, for a given class of system (e.g., three 1 M(circle plus) planets), orbit crossing times vary with planetary spacing approximately as a power law over a wide range of separation in semimajor axis, Chaos tests indicate that deviations from this power law persist for changed initial longitudes and also for small but non-trivial changes in orbital spacing. We find that the stability time increases more rapidly at large initial orbital separations than the power-law dependence predicted from moderate initial orbital separations. Systems of five planets are less stable than systems of three planets for a specified semimajor axis spacing. Furthermore, systems of less massive planets can be packed more closely, being about as stable as 1 M(circle plus) planets when the radial separation between planets is scaled using the Mutual Hin radius. Finally, systems with retrograde planets can be packed Substantially more closely than prograde systems with equal numbers of planets. (c) 2008 Elsevier Inc. All rights reserved.
C1 [Lissauer, Jack J.] NASA, Div Space Sci, Ames Res Ctr, Moffett Field, CA 94035 USA.
[Smith, Andrew W.] Stanford Univ, Dept Mech Engn, Stanford, CA 94305 USA.
RP Lissauer, JJ (reprint author), NASA, Div Space Sci, Ames Res Ctr, MS 245-3, Moffett Field, CA 94035 USA.
EM awsmith@stanford.edu; Jack.J.Lissauer@nasa.gov
FU NASA's Planetary Geology & Geophysics Program [RTOP 344-30-50-01]
FX This work was supported by NASA's Planetary Geology & Geophysics Program
through RTOP 344-30-50-01. We thank Eric Ford, John Charribers, Tony
Dobrovolskis, and Kevin Zahnle for helpful comments on the manuscript,
Amanda Hoffmann for her generous donation of CPU time, and Jason Barnes
for helpful discussions regarding integrators.
NR 18
TC 62
Z9 62
U1 0
U2 3
PU ACADEMIC PRESS INC ELSEVIER SCIENCE
PI SAN DIEGO
PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA
SN 0019-1035
J9 ICARUS
JI Icarus
PD MAY
PY 2009
VL 201
IS 1
BP 381
EP 394
DI 10.1016/j.icarus.2008.12.027
PG 14
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 444CM
UT WOS:000265957900026
ER
PT J
AU Chapin, E
Chen, CW
AF Chapin, Elaine
Chen, Curtis W.
TI Airborne Along-Track Interferometry for GMTI
SO IEEE AEROSPACE AND ELECTRONIC SYSTEMS MAGAZINE
LA English
DT Article
CT 2008 IEEE Radar Conference
CY MAY 26-30, 2008
CL Rome, ITALY
SP IEEE, FINMECCANICA, SELEX, Agilent Technol, Dappolonia, Gedae, IDS, IET, MBDA, McGraw Hill, Natl Instruments, Off Naval Res, Sci & Technol, ROHDE & SCHWARZ, Tektronix, Thales Alenia, altran, ACCSCO, Raytheon
AB Synthetic Aperture Radar (SAR) Along-Track Interferometry (ATI) has been used extensively to measure ocean surface currents. Given its ability to measure small velocities (similar to 10 cm/s) of relatively radar-dark water surfaces, there is great potential that this technique can be adapted for ground moving target indication (GMTI) applications, particularly as a method for detecting very slow targets with small radar cross-sections. Herein, we describe preliminary results from an ATI GMTI experiment.
The SAR data described were collected by the dual-frequency NASA/JPL airborne radar in its standard dual-baseline ATI mode. The radar system imaged a variety of control targets including a pick-up truck, sport utility vehicles, passenger cars, a bicycle, and pedestrians over multiple flight passes. The control targets had horizontal velocities of less than 5 m/s. The cross-sections of the targets were not purposely enhanced, although the targets' reflectivities may have been affected by the existence of the GPS equipment used to record the targets' positions. Single-look and multiple-look interferograms processed to the full azimuth resolution were analyzed. In the data processed to date, all of the targets were observed by visual inspection in at least one of the four combinations of dual-frequency, dual-baseline interferometric data. This extremely promising result demonstrates the potential of ATI for GMTI applications.
C1 [Chapin, Elaine; Chen, Curtis W.] CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA.
RP Chapin, E (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Rd, Pasadena, CA 91125 USA.
NR 6
TC 8
Z9 19
U1 0
U2 5
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 MAY
PY 2009
VL 24
IS 5
BP 13
EP 18
PG 6
WC Engineering, Aerospace; Engineering, Electrical & Electronic
SC Engineering
GA 460DP
UT WOS:000267168400004
ER
PT J
AU Najafizadeh, L
Adams, JS
Phillips, SD
Moen, KA
Cressler, JD
Aslam, S
Stevenson, TR
Meloy, RM
AF Najafizadeh, Laleh
Adams, Joseph S.
Phillips, Stanley D.
Moen, Kurt A.
Cressler, John D.
Aslam, Shahid
Stevenson, Thomas R.
Meloy, Robert M.
TI Sub-1-K Operation of SiGe Transistors and Circuits
SO IEEE ELECTRON DEVICE LETTERS
LA English
DT Article
DE Analog integrated circuits; BiCMOS; cryogenic temperatures;
heterojunction bipolar transistor (HBT); silicon germanium (SiGe); SiGe
HBTs; voltage reference
ID TEMPERATURE; ELECTRONICS; REFERENCES
AB We present the first measurement results for silicon-germanium (SiGe) heterojunction bipolar transistors (HBTs) and SiGe BiCMOS circuits operating in the sub-1-K regime. Robust transistor operation of a first-generation 0.5 x 2.5 x 4-mu m(2) SiGe transistor is demonstrated at package temperatures as low as 300 mK. In addition, a SiGe BiCMOS bandgap voltage reference is verified to be fully functional at operating temperatures below 700 mK. The SiGe voltage reference exhibits a temperature coefficient of 160 ppm/degrees C over the temperature range of 700 mK-300 K.
C1 [Najafizadeh, Laleh; Phillips, Stanley D.; Moen, Kurt A.; Cressler, John D.] Georgia Inst Technol, Sch Elect & Comp Engn, Atlanta, GA 30332 USA.
[Adams, Joseph S.] Univ Maryland, Baltimore, MD 21250 USA.
[Aslam, Shahid; Meloy, Robert M.] MEI Technol Inc, Lanham, MD 20706 USA.
[Aslam, Shahid; Stevenson, Thomas R.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
RP Najafizadeh, L (reprint author), Georgia Inst Technol, Sch Elect & Comp Engn, Atlanta, GA 30332 USA.
EM laleh@ece.gatech.edu; Joseph.S.Adams@nasa.gov; stan.phillips@gatech.edu;
kmoen@ece.gatech.edu; cressler@ece.gatech.edu; Shahid.Aslam-1@nasa.gov;
Thomas.R.Stevens6@nasa.gov; bmeloy@hst.nasa.gov
RI Aslam, Shahid/D-1099-2012
FU National Aeronautics and Space Administration
FX Manuscript received January 15, 2009; revised February 21, 2009. Current
version published April 28, 2009. This work was supported by the
National Aeronautics and Space Administration. The review of this letter
was arranged by Editor M, Ostling.
NR 16
TC 15
Z9 15
U1 0
U2 6
PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
PI PISCATAWAY
PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA
SN 0741-3106
J9 IEEE ELECTR DEVICE L
JI IEEE Electron Device Lett.
PD MAY
PY 2009
VL 30
IS 5
BP 508
EP 510
DI 10.1109/LED.2009.2016767
PG 3
WC Engineering, Electrical & Electronic
SC Engineering
GA 440PH
UT WOS:000265711700028
ER
PT J
AU White, RJ
Peng, GCY
Demir, SS
AF White, Ronald J.
Peng, Grace C. Y.
Demir, Semahat S.
TI Multiscale Modeling of Biomedical, Biological, and Behavioral Systems
(Part 2) Understanding the Body from Atoms to Cells to Tissues to Organs
to Populations
SO IEEE ENGINEERING IN MEDICINE AND BIOLOGY MAGAZINE
LA English
DT Editorial Material
C1 [Peng, Grace C. Y.] Natl Inst Biomed Imaging & Bioengn, NIH, Bethesda, MD 20892 USA.
[Peng, Grace C. Y.] Catholic Univ Amer, Washington, DC 20064 USA.
[Peng, Grace C. Y.] Johns Hopkins Univ, Baltimore, MD 21218 USA.
[White, Ronald J.] NASA, Human Res Program, Washington, DC USA.
[White, Ronald J.] Baylor Coll Med, Houston, TX 77030 USA.
[White, Ronald J.] NASA Headquarters, Div Life Sci, Washington, DC USA.
[White, Ronald J.] Uniformed Serv Univ Hlth Sci, Bethesda, MD 20814 USA.
[White, Ronald J.] Univ Louisiana Lafayette, Lafayette, LA USA.
[Demir, Semahat S.] NASA, SLS 1, Washington, DC USA.
[Demir, Semahat S.] NASA, IML 1, Washington, DC USA.
[Demir, Semahat S.] NASA, US Component German Spacelab Miss D 2, Washington, DC USA.
RP Peng, GCY (reprint author), Natl Inst Biomed Imaging & Bioengn, NIH, 6707 Democracy Blvd,Suite 200,MSC 5469, Bethesda, MD 20892 USA.
EM penggr@mail.nih.gov
NR 0
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 0739-5175
J9 IEEE ENG MED BIOL
JI IEEE Eng. Med. Biol. Mag.
PD MAY-JUN
PY 2009
VL 28
IS 3
BP 8
EP 9
DI 10.1109/MEMB.2009.932490
PG 2
WC Engineering, Biomedical; Medical Informatics
SC Engineering; Medical Informatics
GA 449BK
UT WOS:000266305600004
PM 19457728
ER
PT J
AU Levin, J
Ioannou, P
AF Levin, Jason
Ioannou, Petros
TI Adaptive Mode-Suppression and Disturbance-Rejection Scheme With
Application to Disk Drives
SO IEEE TRANSACTIONS ON CONTROL SYSTEMS TECHNOLOGY
LA English
DT Article
DE Adaptive control; disk drives; disturbance rejection; neural networks;
radial basis functions (RBFs); servo control
ID NOTCH FILTER; SYSTEM-IDENTIFICATION; RUNOUT COMPENSATION;
NEURAL-NETWORKS; SERVO CONTROL; CONTROLLER
AB The goal of a track-following controller for a disk drive is to maintain as close to perfect tracking as possible. Better tracking allows for more data to be stored on a single disk. There are several factors which make this control problem difficult, such as high-frequency resonant modes, unknown disturbances, and a preset sampling rate. The resonant modes of a disk drive are often uncertain and vary between units and can also lie near or beyond the Nyquist frequency. Suppressing these modes can be difficult. However, a multirate adaptive notch filter and adaptive bandwidth controller is proposed to suppress these resonant modes. A robust online estimator that estimates the mode frequencies is used to allow the multirate adaptive notch filter to track the disk drive's modes. By adding a multirate scheme to the adaptive notch filter, it can suppress modes at higher frequencies, which are close to or beyond the Nyquist frequency of the preset sampling rate. As the multirate adaptive notch filter tracks the plant mode frequencies, the adaptive bandwidth controller ensures that stability and performance requirements are satisfied by using the online estimate of the mode frequencies. An adaptive disturbance rejector is added to the adaptive mode-suppression scheme and broken into two parts: a part to suppress the repeatable runout and another to attenuate the residual disturbance by using a neural model. Both parts are adapted online and combined with the mode-suppression scheme to ensure good disturbance rejection even in the presence of unknown or changing resonant modes. Simulation results with a hard disk drive as the application are included and show that the adaptive mode-suppression scheme is able to maintain stability and better performance than a nonadaptive counterpart for an uncertain resonant-mode frequency. When combined with the adaptive disturbance-rejection scheme, stability is maintained and an improvement of as much as 14.3% in 3 sigma is seen. This improvement in tracking can allow for data to be stored more densely on a single disk, providing larger storage media for the same size of disk drive.
C1 [Levin, Jason; Ioannou, Petros] Univ So Calif, Dept Elect Engn Syst, So Calif Ctr Adv Transportat Technol, Los Angeles, CA 90089 USA.
[Levin, Jason] Jet Prop Lab, Pasadena, CA 91103 USA.
[Ioannou, Petros] Univ So Calif, Dept Aerosp & Mech Engn, Los Angeles, CA 90089 USA.
RP Levin, J (reprint author), Univ So Calif, Dept Elect Engn Syst, So Calif Ctr Adv Transportat Technol, Los Angeles, CA 90089 USA.
EM levinj@usc.edu; ioannou@usc.edu
FU NSF Award [CMS-0510921]; NASA [NCC4-158]
FX This work was supported in part by NSF Award CMS-0510921 and by NASA
Grant NCC4-158.
NR 37
TC 6
Z9 6
U1 0
U2 4
PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
PI PISCATAWAY
PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA
SN 1063-6536
EI 1558-0865
J9 IEEE T CONTR SYST T
JI IEEE Trans. Control Syst. Technol.
PD MAY
PY 2009
VL 17
IS 3
BP 620
EP 632
DI 10.1109/TCST.2008.2002813
PG 13
WC Automation & Control Systems; Engineering, Electrical & Electronic
SC Automation & Control Systems; Engineering
GA 440PG
UT WOS:000265711600011
ER
PT J
AU Trigwell, S
Captain, JG
Arens, EE
Quinn, JW
Calle, CI
AF Trigwell, Steve
Captain, James G.
Arens, Ellen E.
Quinn, Jacqueline W.
Calle, Carlos I.
TI The Use of Tribocharging in the Electrostatic Beneficiation of Lunar
Simulant
SO IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS
LA English
DT Article; Proceedings Paper
CT Joint Conference of the
Electrostatics-Society-of-America/IEEE-Industrial-Applications-Society/I
nstitute-of-Electrostatics-Japan/Societe-Francaise-of-Electrostatique
CY JUN 06-09, 2006
CL Berkeley, CA
SP Electrostat Soc Amer, IEEE Ind Applicat Soc, Inst Electrostat Japan, Soc Francaise Electrostat
DE Beneficiation; lunar simulant; tribocharging; work function; X-ray
photoelectron spectroscopy (XPS)
AB The use of tribocharging as a potential method to provide sufficient charge to several different lunar simulants for electrostatic beneficiation was investigated. The objective was to determine whether specific minerals of interest (e.g., ilmenite) that are present in lunar regolith could be enriched in concentration by beneficiation that would therefore allow for more efficient extraction for in situ resource utilization use. The production of oxygen, water, and other resources on the Moon from raw materials is vital for future missions to the Moon. Successful separation of ilmenite was achieved for a prepared simulant (KSC-1), which is a mixture of pure commercially supplied pyroxene, olivine, feldspar, and ilmenite, in a 4:4: 1 : 1 ratio, showing proof of concept when tribocharged against three different charging materials, namely, Al, Cu, and PTFE. Separation by chemical composition was also observed for existing lunar simulants JSC-1 and JSC-1A; however, the interpretation of the separation was difficult due to the complex mineralogy of the simulants compared to the simple prepared mixture.
C1 [Trigwell, Steve; Captain, James G.] ASRC Aerosp ASRC 24, Appl Sci & Technol Dept, Kennedy Space Ctr, FL 32899 USA.
[Arens, Ellen E.; Quinn, Jacqueline W.; Calle, Carlos I.] NASA, Kennedy Space Ctr, FL 32899 USA.
RP Trigwell, S (reprint author), ASRC Aerosp ASRC 24, Appl Sci & Technol Dept, Kennedy Space Ctr, FL 32899 USA.
EM steven.trigwell-1@nasa.gov; james.g.captain@nasa.gov;
ellen.e.arens@nasa.gov; jacqueline.w.quinn@nasa.gov;
carlos.i.calle@nasa.gov
NR 14
TC 11
Z9 11
U1 1
U2 6
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 MAY-JUN
PY 2009
VL 45
IS 3
BP 1060
EP 1067
DI 10.1109/TIA.2009.2018976
PG 8
WC Engineering, Multidisciplinary; Engineering, Electrical & Electronic
SC Engineering
GA 451EE
UT WOS:000266452700018
ER
PT J
AU Hatamleh, O
AF Hatamleh, Omar
TI A comprehensive investigation on the effects of laser and shot peening
on fatigue crack growth in friction stir welded AA 2195 joints
SO INTERNATIONAL JOURNAL OF FATIGUE
LA English
DT Article
DE Friction stir welding; Laser peening; Shot peening; Fatigue crack
growth; Stress ratio, 2195
ID RESIDUAL-STRESS MEASUREMENTS; ALUMINUM-ALLOYS; MECHANICAL-PROPERTIES;
WELDING SPEED; BEHAVIOR; MICROSTRUCTURE; CORROSION; PROPAGATION;
LITHIUM; LIFE
AB The effects of various surface treatment techniques on the fatigue crack growth performance of friction stir welded 2195 aluminum alloy were investigated. The objective was to reduce fatigue crack growth rates and enhance the fatigue life of welded joints. The crack growth rates were assessed and characterized for different peening conditions at a stress ratio (R) of 0.1, and 0.7. The surface and through-thickness residual stress distribution were also investigated and presented for the various regions in the weld. Tensile residual stresses introduced during the welding process were found to become significantly compressive, particularly after laser peening. The effect of the compressive stresses was deemed responsible for increasing the resistance to fatigue crack growth of the welds. The results indicate a significant reduction in fatigue crack growth rates using laser peening compared to shot peening and native welded specimens. This reduced fatigue crack growth rate was comparable to the base unwelded material. Published by Elsevier Ltd.
C1 NASA, Lyndon B Johnson Space Ctr, Struct Branch, Houston, TX 77058 USA.
RP Hatamleh, O (reprint author), NASA, Lyndon B Johnson Space Ctr, Struct Branch, Houston, TX 77058 USA.
EM omar.hatamleh-1@nasa.gov
NR 68
TC 48
Z9 50
U1 1
U2 27
PU ELSEVIER SCI LTD
PI OXFORD
PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND
SN 0142-1123
J9 INT J FATIGUE
JI Int. J. Fatigue
PD MAY
PY 2009
VL 31
IS 5
BP 974
EP 988
DI 10.1016/j.ijfatigue.2008.03.029
PG 15
WC Engineering, Mechanical; Materials Science, Multidisciplinary
SC Engineering; Materials Science
GA 421JK
UT WOS:000264355000019
ER
PT J
AU Carney, KS
Pereira, JM
Revilock, DM
Matheny, P
AF Carney, K. S.
Pereira, J. M.
Revilock, D. M.
Matheny, P.
TI Jet engine fan blade containment using an alternate geometry
SO INTERNATIONAL JOURNAL OF IMPACT ENGINEERING
LA English
DT Article
DE Containment; Fan case; Blade off; Turbine engine; Very high strain rate
material behavior
ID STRAIN-RATE COMPRESSION; ALLOYS
AB With a goal of reducing jet engine weight. simulations of a fan blade containment system with an alternate geometry were tested and analyzed. A projectile simulating a fan blade was shot at two alternate geometry containment case configurations using a gas gun. The first configuration was a flat plate representing a standard case configuration. The second configuration was a flat plate with a radially convex curve section at the impact point. The curved surface was designed to force the blade to deform plastically, dissipating energy before the full impact of the blade is received by the plate. The curved case was able to tolerate a higher impact velocity before failure. The computational model was developed and correlated with the tests and a weight savings assessment was performed. For the particular test configuration used in this study the ballistic impact velocity of the curved plate was approximately 60 m/s (200 ft/s) greater than that of the flat plate. For the computational model to successfully duplicate the test, the very high strain rate behavior of the materials had to be incorporated. Published by Elsevier Ltd.
C1 [Carney, K. S.; Pereira, J. M.; Revilock, D. M.] NASA, Glenn Res Ctr, Cleveland, OH 44135 USA.
[Matheny, P.] Florida Turbine Technol, W Palm Beach, FL USA.
RP Carney, KS (reprint author), NASA, Glenn Res Ctr, 21000 Brookpk Rd, Cleveland, OH 44135 USA.
EM kelly.s.carney@nasa.gov
NR 24
TC 15
Z9 17
U1 1
U2 5
PU PERGAMON-ELSEVIER SCIENCE LTD
PI OXFORD
PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND
SN 0734-743X
J9 INT J IMPACT ENG
JI Int. J. Impact Eng.
PD MAY
PY 2009
VL 36
IS 5
BP 720
EP 728
DI 10.1016/j.ijimpeng.2008.10.002
PG 9
WC Engineering, Mechanical; Mechanics
SC Engineering; Mechanics
GA 421MB
UT WOS:000264361900008
ER
PT J
AU Vaishampayan, P
Miyashita, M
Ohnishi, A
Satomi, M
Rooney, A
La Duc, MT
Venkateswaran, K
AF Vaishampayan, Parag
Miyashita, Mika
Ohnishi, Akihiro
Satomi, Masataka
Rooney, Alejandro
La Duc, Myron T.
Venkateswaran, Kasthuri
TI Description of Rummeliibacillus stabekisii gen. nov., sp nov and
reclassification of Bacillus pycnus Nakamura et al. 2002 as
Rummeliibacillus pycnus comb. nov.
SO INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY
LA English
DT Article
ID SPACECRAFT-ASSEMBLY FACILITY; CLASSIFICATION; SPHAERICUS; RESISTANT;
BACTERIA; PROPOSAL; NEIDEI; SPORES
AB Strains of aerobic, Gram-positive, rod-shaped, round-spore-forming bacteria were isolated from different geographical locations and a subsequent polyphasic study was undertaken to clarify the T taxonomic position of the round-spore-forming isolates strain KSC-SF6g(T), strain M32 and strain NBRC 12622. 16S rRNA gene sequence similarities demonstrated that these strains were most closely affiliated with Bacillus pycnus NRRL NRS-1691(T) (98%), with species of Kurthia (96%) and Viridibacillus (94-96%) as the next nearest relatives. However, while DNA-DNA hybridization studies showed approx. 70% reassociation among strains KSC-SF6g(T), M32 and NBRC 12622, DNA-DNA hybridization values between these strains and B. pycnus NRRL NRS-1691(T) never exceeded 13%. Differences in the molecular structure of the cell-wall peptidoglycan could not differentiate these strains sufficiently from other closely related genera (Viridibacillus and Kurthia). However, Lys-Asp was present in strains KSC-SF6g(T), M32 and NBRC 12622, whereas L-Lys-D-Glu was reported in B. pycnus NRRL NRS-1691(T). The menaquinone MK-7 was dominant in strains KSC-SF6g(T), M32 and NBRC 12622 and members of the genus Kurthia, whereas MK-8 was abundant in Viridibacillus species. Strains KSC-SF6g(T), M32 and NBRC 12622 exhibited fatty acid profiles consisting of major amounts of anteiso-C(15:0) (similar to 50%) and iso-C(15:0) (similar to 25%) and moderate amounts of anteiso-C(17:0) (similar to 7%), which discriminated them from closely related B. pycnus NRRL NRS-1691(T) and species of Viridibacillus (iso-C15:0; 46-74%). The authors propose that strains KSC-SF6g(T), M32 and NBRC 12622 and B. pycnus NRRL NRS-1691(T) be reclassified into a separate genus based on clear-cut differences in discriminative taxonomic markers and the distant placement of B. pycnus and the novel strains described herein from other species of this clade according to current 16S rRNA gene sequence-based relatedness (similar to 4% difference in sequence). We propose the placement of these isolates into the novel genus Rummeliibacillus gen. nov. For the new taxon comprising strains KSC-SF6g(T), M32 and NBRC 12622, we propose the name Rummeliibacillus stabekisii gen. nov., sp. nov. (the type species of Rummeliibacillus), represented by the type strain KSC-SF6g(T) (=NRRL B-51320(T) =NBRC 104870(T)). In addition, Bacillus pycnus, which bears traits distinct from other round-spore-forming species [i.e. absence of growth at high NaCl (7%), positive reaction for gelatin liquefaction], is reclassified as Rummeliibacillus pycnus comb. nov. (type strain JCM 11075(T) =NRRL NRS-1691(T)) based on phylogenetic affiliations and phenotypic characterization.
C1 [Vaishampayan, Parag; La Duc, Myron T.; Venkateswaran, Kasthuri] CALTECH, Biotechnol & Planetary Protect Grp, Jet Prop Lab, Pasadena, CA 91109 USA.
[Miyashita, Mika] Biol Res Ctr, Natl Inst Technol & Evaluat, Chiba 2920818, Japan.
[Ohnishi, Akihiro] Tokyo Univ Agr, Dept Fermentat Sci, Fac Appl Biosci, Setagaya Ku, Tokyo 1568502, Japan.
[Satomi, Masataka] Fisheries Res Agcy, Natl Res Inst Fisheries Sci, Yokohama, Kanagawa 2368648, Japan.
[Rooney, Alejandro] Natl Ctr Agr Utilizat Res, USDA, Peoria, IL 61604 USA.
RP Venkateswaran, K (reprint author), CALTECH, Biotechnol & Planetary Protect Grp, Jet Prop Lab, Pasadena, CA 91109 USA.
EM kjvenkat@jpl.nasa.gov
FU National Aeronautics and Space Administration; NRA-ROSES; Cassie Conley
FX The research described in this publication was carried out at the jet
Propulsion Laboratory, California Institute of Technology, under a
contract with the National Aeronautics and Space Administration. This
research was funded by a 2006 NRA-ROSES grant. We are grateful to Cassie
Conley for such funding. The authors extend thanks to Shariff Osman for
sampling and to all of the members of the JPL Biotechnology and
Planetary Protection Group for technical assistancc.
NR 24
TC 19
Z9 26
U1 0
U2 8
PU SOC GENERAL MICROBIOLOGY
PI READING
PA MARLBOROUGH HOUSE, BASINGSTOKE RD, SPENCERS WOODS, READING RG7 1AG,
BERKS, ENGLAND
SN 1466-5026
J9 INT J SYST EVOL MICR
JI Int. J. Syst. Evol. Microbiol.
PD MAY
PY 2009
VL 59
BP 1094
EP 1099
DI 10.1099/ijs.0.006098-0
PG 6
WC Microbiology
SC Microbiology
GA 450UL
UT WOS:000266426400030
PM 19406799
ER
PT J
AU Foster, JS
Green, SJ
Ahrendt, SR
Golubic, S
Reid, RP
Hetherington, KL
Bebout, L
AF Foster, Jamie S.
Green, Stefan J.
Ahrendt, Steven R.
Golubic, Stjepko
Reid, R. Pamela
Hetherington, Kevin L.
Bebout, Lee
TI Molecular and morphological characterization of cyanobacterial diversity
in the stromatolites of Highborne Cay, Bahamas
SO ISME JOURNAL
LA English
DT Article
DE cyanobacteria; stromatolites; microbial diversity
ID MODERN MARINE STROMATOLITES; HYPERSALINE MICROBIAL MAT; POLYMERIC
SECRETIONS EPS; RIBOSOMAL-RNA GENES; COMMUNITY STRUCTURE; SP-NOV;
ENDOLITHIC CYANOBACTERIA; SUBTIDAL STROMATOLITES; FORMING CYANOBACTERIA;
VERTICAL MIGRATION
AB Stromatolites are sedimentary deposits that are the direct result of interactions between microbes and their surrounding environment. Once dominant on ancient Earth, actively forming stromatolites now occur in just a few remote locations around the globe, such as the island of Highborne Cay, Bahamas. Although the stromatolites of Highborne Cay contain a wide range of metabolically diverse organisms, photosynthetic cyanobacteria are the driving force for stromatolite development. In this study, we complement previous morphological data by examining the cyanobacterial phylogenetic and physiological diversity of Highborne Cay stromatolites. Molecular analysis of both clone and culture libraries identified 33 distinct phylotypes within the stromatolites. Culture libraries exhibited several morphologically similar but genetically distinct ecotypes, which may contribute to ecosystem stability within the stromatolites. Several of the cultured isolates exhibited both a positive phototactic response and light-dependent extracellular polymeric secretions production, both of which are critical phenotypes for stromatolite accretion and development. The results of this study reveal that the genetic diversity of the cyanobacterial populations within the Highborne Cay stromatolites is far greater than previous estimates, indicating that the mechanisms of stromatolite formation and accretion may be more complex than had been previously assumed. The ISME Journal (2009) 3, 573-587; doi:10.1038/ismej.2008.129; published online 15 January 2009
C1 [Foster, Jamie S.; Ahrendt, Steven R.; Hetherington, Kevin L.] Univ Florida, Space Life Sci Lab, Dept Microbiol & Cell Sci, Kennedy Space Ctr, FL 32899 USA.
[Green, Stefan J.] Florida State Univ, Dept Oceanog, Tallahassee, FL 32306 USA.
[Golubic, Stjepko] Boston Univ, Dept Biol, Boston, MA 02215 USA.
[Reid, R. Pamela] Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Miami, FL 33149 USA.
[Bebout, Lee] NASA, Ames Res Ctr, Exobiol Branch, Moffett Field, CA 94035 USA.
RP Foster, JS (reprint author), Univ Florida, Space Life Sci Lab, Dept Microbiol & Cell Sci, Bldg M6-1025,Room 234, Kennedy Space Ctr, FL 32899 USA.
EM jfoster@ufl.edu
RI Green, Stefan/C-8980-2011;
OI Green, Stefan/0000-0003-2781-359X
FU Florida Space Research and Education, Florida Space Grant Consortium
(UCF) [UCF-0000127787]; Department of Microbiology and Cell Science,
University of Florida [0649198]; NSF Biocomplexity [EAR-0221796]
FX We would like to thank Olivier Braissant, John Stolz and Pieter Visscher
for helpful discussions and critical review of this article. We would
also like to thank Tracy Cote and Alice Herbert for their technical
assistance. This work was supported by a Florida Space Research and
Education grant awarded to JSF by the Florida Space Grant Consortium
(UCF Project no. UCF-0000127787). An NSF REU grant (no. 0649198) awarded
to the Department of Microbiology and Cell Science, University of
Florida supported SA Transportation and field collection was supported
by the NSF Biocomplexity grant EAR-0221796 awarded to RPR.
NR 86
TC 53
Z9 55
U1 2
U2 22
PU NATURE PUBLISHING GROUP
PI NEW YORK
PA 75 VARICK ST, 9TH FLR, NEW YORK, NY 10013-1917 USA
SN 1751-7362
J9 ISME J
JI ISME J.
PD MAY
PY 2009
VL 3
IS 5
BP 573
EP 587
DI 10.1038/ismej.2008.129
PG 15
WC Ecology; Microbiology
SC Environmental Sciences & Ecology; Microbiology
GA 444DK
UT WOS:000265960400007
PM 19148145
ER
PT J
AU Dick, SJ
AF Dick, Steven J.
TI The Transit of Venus Enterprise in Victorian Britain.
SO JOURNAL FOR THE HISTORY OF ASTRONOMY
LA English
DT Book Review
C1 [Dick, Steven J.] NASA, Washington, DC 20546 USA.
RP Dick, SJ (reprint author), NASA, Washington, DC 20546 USA.
EM Steven.J.Dick@nasa.gov
NR 1
TC 0
Z9 0
U1 0
U2 2
PU SCIENCE HISTORY PUBLICATIONS LTD
PI CAMBRIDGE
PA 16 RUTHERFORD RD, CAMBRIDGE CB2 2HH, ENGLAND
SN 0021-8286
J9 J HIST ASTRON
JI J. Hist. Astron.
PD MAY
PY 2009
VL 40
BP 232
EP 233
PG 2
WC History & Philosophy Of Science
SC History & Philosophy of Science
GA 445QB
UT WOS:000266065500016
ER
PT J
AU Jardin, MR
Mueller, ER
AF Jardin, Matt R.
Mueller, Eric R.
TI Optimized Measurements of Unmanned-Air-Vehicle Mass Moment of Inertia
with a Bifilar Pendulum
SO JOURNAL OF AIRCRAFT
LA English
DT Article; Proceedings Paper
CT AIAA Guidance, Navigation, and Control Conference
CY AUG 20-23, 2007
CL Hilton Head Isl, SC
AB A bifilar (two-wire) pendulum is a torsional pendulum consisting of a test object suspended by two thin parallel wires. The pendulum oscillates about the vertical axis. The restoring torque of the bifilar pendulum is provided by the gravitational force as rotations from the rest state cause the test object to raise slightly. The mass moment of inertia is computed using dynamic modeling, measurements of the oscillation period, and the physical dimensions of the bifilar pendulum such as the length and separation displacement of the pendulum wires. A simulation technique is described that improves estimates of the mass moment of inertia by considering the nonlinear effects of damping and large angular displacements. An analysis of the error variance of mass moment of inertia measurements is also described. The resulting expression for the error variance is used to optimize the physical parameters of the bifilar pendulum to obtain the moment of inertia measurement with the minimum error variance. Monte Carlo simulations were used to validate the parameter optimization technique. Experimental results are presented for a uniform-density test object for which the moment of inertia is straightforward to compute from geometric considerations. Results are also presented for a small unmanned air vehicle, which was the intended application for this moment of inertia measurement technique.
C1 [Jardin, Matt R.] MathWorks Inc, Consulting Serv Grp, Natick, MA 01760 USA.
[Mueller, Eric R.] NASA, Ames Res Ctr, Automat Concepts Res Branch, Moffett Field, CA 94035 USA.
RP Jardin, MR (reprint author), MathWorks Inc, Consulting Serv Grp, 3 Apple Hill Dr, Natick, MA 01760 USA.
NR 10
TC 2
Z9 5
U1 1
U2 3
PU AMER INST AERONAUT ASTRONAUT
PI RESTON
PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA
SN 0021-8669
J9 J AIRCRAFT
JI J. Aircr.
PD MAY-JUN
PY 2009
VL 46
IS 3
BP 763
EP 775
DI 10.2514/1.34015
PG 13
WC Engineering, Aerospace
SC Engineering
GA 456ZQ
UT WOS:000266894200004
ER
PT J
AU Mavriplis, DJ
Vassberg, JC
Tinoco, EN
Mani, M
Brodersen, OP
Eisfeld, B
Wahls, RA
Morrison, JH
Zickuhr, T
Levy, D
Murayama, M
AF Mavriplis, Dimitri J.
Vassberg, John C.
Tinoco, Edward N.
Mani, Mori
Brodersen, Olaf P.
Eisfeld, Bernhard
Wahls, Richard A.
Morrison, Joseph H.
Zickuhr, Tom
Levy, David
Murayama, Mitsuhiro
TI Grid Quality and Resolution Issues from the Drag Prediction Workshop
Series
SO JOURNAL OF AIRCRAFT
LA English
DT Article; Proceedings Paper
CT AIAA 46th Aerospace Sciences Meeting and Exhibit
CY JAN 07-10, 2008
CL Reno, NV
SP Amer Inst Aeronaut & Astronaut
ID COMPUTATIONS
AB The drag prediction workshop series, held over the last six years and sponsored by the AIAA Applied Aerodynamics Committee, has been extremely useful in providing an assessment of the state of the art in computationally based aerodynamic drag prediction. An emerging consensus from the three-workshop series has been the identification of spatial discretization errors as a dominant error source in absolute as well as incremental drag prediction. This paper provides an overview of the collective experience from the workshop series regarding the effect of grid-related issues on overall drag prediction accuracy. Examples based on workshop results are used to illustrate the effect of grid resolution and grid quality on drag prediction, and grid convergence behavior is examined in detail. For fully attached flows, various accurate and successful workshop results are demonstrated, and anomalous behavior is identified for a number of cases involving substantial regions of separated flow. Based on collective workshop experiences, recommendations for improvements in mesh generation technology that have the potential to impact the state of the art of aerodynamic drag prediction are given.
C1 [Mavriplis, Dimitri J.] Univ Wyoming, Dept Mech Engn, Laramie, WY 82071 USA.
[Vassberg, John C.] Boeing Co, Huntington Beach, CA 92647 USA.
[Tinoco, Edward N.] Boeing Co, Seattle, WA 98124 USA.
[Mani, Mori] Boeing Co, St Louis, MO 63301 USA.
[Brodersen, Olaf P.; Eisfeld, Bernhard] German Aerosp Ctr, DLR, Inst Aerodynam & Flow Technol, D-38108 Braunschweig, Germany.
[Wahls, Richard A.] NASA, Langley Res Ctr, Configurat Aerodynam Branch, Hampton, VA 23681 USA.
[Morrison, Joseph H.] NASA, Langley Res Ctr, Computat Aerosci Branch, Hampton, VA 23681 USA.
[Zickuhr, Tom; Levy, David] Cessna Aircraft Co, Wichita, KS 67218 USA.
[Murayama, Mitsuhiro] Japan Aerosp Explorat Agcy, Civil Transport Team, Aviat Program Grp, Chofu, Tokyo 1828522, Japan.
RP Mavriplis, DJ (reprint author), Univ Wyoming, Dept Mech Engn, Laramie, WY 82071 USA.
NR 37
TC 9
Z9 9
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 MAY-JUN
PY 2009
VL 46
IS 3
BP 935
EP 950
DI 10.2514/1.39201
PG 16
WC Engineering, Aerospace
SC Engineering
GA 456ZQ
UT WOS:000266894200020
ER
PT J
AU Herring, GC
AF Herring, G. C.
TI Noninvasive Measurement of Velocity, Pressure, and Temperature in
Unseeded Supersonic Air Vortices
SO JOURNAL OF AIRCRAFT
LA English
DT Article
C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA.
RP Herring, GC (reprint author), NASA, Langley Res Ctr, Mail Stop 493, Hampton, VA 23681 USA.
EM Gregory.C.Herring@nasa.gov
NR 10
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 0021-8669
J9 J AIRCRAFT
JI J. Aircr.
PD MAY-JUN
PY 2009
VL 46
IS 3
BP 1074
EP 1076
DI 10.2514/1.42004
PG 3
WC Engineering, Aerospace
SC Engineering
GA 456ZQ
UT WOS:000266894200036
ER
PT J
AU Housman, JA
Kiris, CC
Hafez, MM
AF Housman, Jeffrey A.
Kiris, Cetin C.
Hafez, Mohamed M.
TI Time-Derivative Preconditioning Methods for Multicomponent Flows-Part
II: Two-Dimensional Applications
SO JOURNAL OF APPLIED MECHANICS-TRANSACTIONS OF THE ASME
LA English
DT Article
DE hybrid conservative/nonconservative method; split coefficient matrix
(SCM) method; time-derivative preconditioning; dual time stepping
AB A time-derivative preconditioned system of equations suitable for the numerical simulation of multicomponent/multiphase inviscid flows at all speeds was described in Part I of this paper. The system was shown to be hyperbolic in time and remain well conditioned in the incompressible limit, allowing time marching numerical methods to remain an efficient solution strategy. Application of conservative numerical methods to multicomponent flows containing sharp fluid interfaces was shown to generate nonphysical pressure and velocity oscillations across the contact surface, which separates the fluid components. It was demonstrated using the one-dimensional Riemann problem that these oscillations may lead to stability problems when the interface separates fluids with large density ratios, such as water and air. The effect of which leads to the requirement of small physical time steps and slow subiteration convergence for the implicit time marching numerical method. Alternatively, the nonconservative and hybrid formulations developed by the present authors were shown to eliminate this nonphysical behavior. While the nonconservative method did not converge to the correct weak solution for flow containing shocks, the hybrid method was able to capture the physically correct entropy solution and converge to the exact solution of the Riemann problem as the grid is refined. In Part II of this paper, the conservative, nonconservative, and hybrid formulations described in Part I are implemented within a two-dimensional structured body-fitted overset grid solver, and a study of two unsteady flow applications is reported. In the first application, a multiphase cavitating flow around a NACA0015 hydrofoil contained in a channel is solved, and sensitivity to the cavitation number and the spatial order of accuracy of the discretization are discussed. Next, the interaction of a shock moving in air with a cylindrical bubble of another fluid is analyzed. In the first case, the cylindrical bubble is filled with helium gas, and both the conservative and hybrid approaches perform similarly. In the second case, the bubble is filled with water and the conservative method fails to maintain numerical stability. The performance of the hybrid method is shown to be unchanged when the gas is replaced with a liquid, demonstrating the robustness and accuracy of the hybrid approach. [DOI:10.1115/1.3086592]
C1 [Housman, Jeffrey A.; Hafez, Mohamed M.] Univ Calif Davis, Davis, CA 95616 USA.
[Kiris, Cetin C.] NASA, Ames Res Ctr, Adv Supercomp Div, Moffett Field, CA 94035 USA.
RP Housman, JA (reprint author), Univ Calif Davis, 2132 Bainer Hall,1 Shields Ave, Davis, CA 95616 USA.
NR 12
TC 0
Z9 0
U1 0
U2 1
PU ASME-AMER SOC MECHANICAL ENG
PI NEW YORK
PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA
SN 0021-8936
J9 J APPL MECH-T ASME
JI J. Appl. Mech.-Trans. ASME
PD MAY
PY 2009
VL 76
IS 3
AR 031013
DI 10.1115/1.3086592
PG 12
WC Mechanics
SC Mechanics
GA 442EC
UT WOS:000265821800013
ER
PT J
AU Roithmayr, CM
Hodges, DH
AF Roithmayr, Carlos M.
Hodges, Dewey H.
TI An Argument Against Augmenting the Lagrangean for Nonholonomic Systems
SO JOURNAL OF APPLIED MECHANICS-TRANSACTIONS OF THE ASME
LA English
DT Article
DE holonomic constraint equations; nonholonomic constraint equations;
Lagrangean; Kane's method; constraint forces
ID CONSTRAINTS
AB Although it is known that correct dynamical equations of motion for a nonholonomic system cannot be obtained from a Lagrangean that has been augmented with a sum of the nonholonomic constraint equations weighted with multipliers, previous publications suggest otherwise. One published example that was proposed in support of augmentation purportedly demonstrates that an accepted method fails to produce correct equations of motion whereas augmentation leads to correct equations. This present paper shows that, in fact, the opposite is true. The correct equations, previously discounted on the basis of a flawed application of the Newton-Euler method, are verified by using Kane's method together with a new approach for determining the directions of constraint forces. [DOI:10.1115/1.3086435]
C1 [Roithmayr, Carlos M.] NASA, Langley Res Ctr, Hampton, VA 23681 USA.
[Hodges, Dewey H.] Georgia Inst Technol, Sch Aerosp Engn, Atlanta, GA 30332 USA.
RP Roithmayr, CM (reprint author), NASA, Langley Res Ctr, Hampton, VA 23681 USA.
EM c.m.roithmayr@larc.nasa.gov; dhodges@gatech.edu
NR 12
TC 2
Z9 2
U1 1
U2 1
PU ASME-AMER SOC MECHANICAL ENG
PI NEW YORK
PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA
SN 0021-8936
J9 J APPL MECH-T ASME
JI J. Appl. Mech.-Trans. ASME
PD MAY
PY 2009
VL 76
IS 3
AR 034501
DI 10.1115/1.3086435
PG 3
WC Mechanics
SC Mechanics
GA 442EC
UT WOS:000265821800018
ER
PT J
AU Sengupta, A
AF Sengupta, Anita
TI Magnetic confinement in a ring-cusp ion thruster discharge plasma
SO JOURNAL OF APPLIED PHYSICS
LA English
DT Article
ID CROSS-SECTIONS; CONTAINMENT; MULTIPOLAR
AB An experimental investigation, in conjunction with a volume averaged analytical model, has been developed to improve the confinement and production of the discharge plasma for plasma thrusters and ion sources. The research conducted explores the discharge performance of a ring-cusp ion source based on the magnetic field configuration, geometry, and power level. Analytical formulations for electron and ion confinement are developed to predict the ionization efficiency for a given discharge chamber design. Explicit determination of discharge loss and volume averaged plasma parameters are obtained via a series of experimental measurements on a ring-cusp NASA Solar Technology Application Readiness (NSTAR) ion thruster to assess the validity of the analytical model. Measurements of the discharge loss with multiple magnetic field configurations compare well with plasma parameter predictions for propellant utilizations between 80% and 95%. The results indicate that increasing the magnetic strength of the first closed magnetic contour line reduces Maxwellian electron diffusion and electrostatically confines the ion population and subsequent loss to the anode wall. The results also indicate that increasing the strength and minimizing the area of the magnetic cusps improves primary electron confinement, increasing the probability of an ionization collision prior to loss at the cusp. (C) 2009 American Institute of Physics. [DOI: 10.1063/1.3106087]
C1 CALTECH, Jet Prop Lab, NASA, Pasadena, CA 91109 USA.
RP Sengupta, A (reprint author), CALTECH, Jet Prop Lab, NASA, 4800 Oak Grove Dr, Pasadena, CA 91109 USA.
EM anita.sengupta@jpl.nasa.gov
FU National Aeronautics and Space Administration
FX The Jet Propulsion Laboratory, California Institute of Technology funded
the research described in this paper under a contract with the National
Aeronautics and Space Administration.
NR 31
TC 5
Z9 5
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 MAY 1
PY 2009
VL 105
IS 9
AR 093303
DI 10.1063/1.3106087
PG 10
WC Physics, Applied
SC Physics
GA 448LE
UT WOS:000266263300023
ER
PT J
AU Wang, JX
Wolff, DB
AF Wang, Jianxin
Wolff, David B.
TI Comparisons of Reflectivities from the TRMM Precipitation Radar and
Ground-Based Radars
SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY
LA English
DT Article
ID MEASURING MISSION TRMM; VALIDATION; SATELLITE; KWAJALEIN; AIRBORNE;
CALIBRATION; WSR-88D; SPACE; SITE
AB Given the decade-long and highly successful Tropical Rainfall Measuring Mission (TRMM), it is now possible to provide quantitative comparisons between ground-based radars (GRs) and the spaceborne TRMM precipitation radar (PR) with greater certainty over longer time scales in various tropical climatological regions. This study develops an automated methodology to match and compare simultaneous TRMM PR and GR reflectivities at four primary TRMM Ground Validation (GV) sites: Houston, Texas (HSTN); Melbourne, Florida (MELB); Kwajalein, Republic of the Marshall Islands (KWAJ); and Darwin, Australia (DARW). Data from each instrument are resampled into a three-dimensional Cartesian coordinate system. The horizontal displacement during the PR data resampling is corrected. Comparisons suggest that the PR suffers significant attenuation at lower levels, especially in convective rain. The attenuation correction performs quite well for convective rain but appears to slightly overcorrect in stratiform rain. The PR and GR observations at HSTN, MELB, and KWAJ agree to about 61 dB on average with a few exceptions, whereas the GR at DARW requires +1 to -5 dB calibration corrections. One of the important findings of this study is that the GR calibration offset is dependent on the reflectivity magnitude. Hence, it is proposed that the calibration should be carried out by using a regression correction rather than by simply adding an offset value to all GR reflectivities.
This methodology is developed to assist TRMM GV efforts to improve the accuracy of tropical rain estimates, but can also be applied to the proposed Global Precipitation Measurement and other related activities over the globe.
C1 [Wang, Jianxin] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
Sci Syst & Applicat Inc, Lanham, MD USA.
RP Wang, JX (reprint author), NASA, Goddard Space Flight Ctr, Code 613-1, Greenbelt, MD 20771 USA.
EM jianxin.wang@nasa.gov
RI Wolff, David/H-5502-2012
FU NASA [NNG06HX15]
FX This study was supported by NASA Grant NNG06HX15. We thank Dr. Ramesh
Kakar (NASA headquarters), Mr. Richard Lawrence (Chief, NASA Goddard
Space Flight Center TRMM Satellite Validation Office), Dr. Scott Braun
(TRMM Project Scientist), and Dr. Robert Adler (former TRMM Project
Scientist) for their support and guidance for the TRMM GV Program. Our
GV colleagues D. A. Marks, D. S. Silberstein, and J. L. Pippitt provided
KWAJ version 7 GR products and monthly Ze-R relations. The PR version 6
and GR version 5 products were obtained from the Distributed Active
Archive Center at NASA's Goddard Space Flight Center.
NR 27
TC 18
Z9 21
U1 0
U2 4
PU AMER METEOROLOGICAL SOC
PI BOSTON
PA 45 BEACON ST, BOSTON, MA 02108-3693 USA
SN 0739-0572
J9 J ATMOS OCEAN TECH
JI J. Atmos. Ocean. Technol.
PD MAY
PY 2009
VL 26
IS 5
BP 857
EP 875
DI 10.1175/2008JTECHA1175.1
PG 19
WC Engineering, Ocean; Meteorology & Atmospheric Sciences
SC Engineering; Meteorology & Atmospheric Sciences
GA 456HA
UT WOS:000266833600001
ER
PT J
AU Condron, A
Winsor, P
Hill, C
Menemenlis, D
AF Condron, Alan
Winsor, Peter
Hill, Chris
Menemenlis, Dimitris
TI Simulated Response of the Arctic Freshwater Budget to Extreme NAO Wind
Forcing
SO JOURNAL OF CLIMATE
LA English
DT Article
ID NORTH-ATLANTIC OSCILLATION; GREAT SALINITY ANOMALIES; COLD HALOCLINE
LAYER; ICE-OCEAN MODEL; SEA-ICE; THERMOHALINE CIRCULATION; CLIMATE
VARIABILITY; IMPACT; ARCHIPELAGO; THICKNESS
AB The authors investigate the response of the Arctic Ocean freshwater budget to changes in the North Atlantic Oscillation (NAO) using a regional-ocean configuration of the Massachusetts Institute of Technology GCM (MITgcm) and carry out several different 10-yr and 30-yr integrations. At 1/6 degrees (similar to 18 km) resolution the model resolves the major Arctic transport pathways, including Bering Strait and the Canadian Archipelago. Two main calculations are performed by repeating the wind fields of two contrasting NAO years in each run for the extreme negative and positive NAO phases of 1969 and 1989, respectively. These calculations are compared both with a control run and the compiled observationally based freshwater budget estimate of Serreze et al.
The results show a clear response in the Arctic freshwater budget to NAO forcing, that is, repeat NAO negative wind forcing results in virtually all freshwater being retained in the Arctic, with the bulk of the freshwater content being pooled in the Beaufort gyre. In contrast, repeat NAO positive forcing accelerates the export of freshwater out of the Arctic to the North Atlantic, primarily via Fram Strait (similar to 900 km(3) yr(-1)) and the Canadian Archipelago (similar to 500 km(3) yr(-1)), with a total loss in freshwater storage of similar to 13 000 km(3) (15%) after 10 yr. The large increase in freshwater export through the Canadian Archipelago highlights the important role that this gateway plays in redistributing the freshwater of the Arctic to subpolar seas, by providing a direct pathway from the Arctic basin to the Labrador Sea, Gulf Stream system, and Atlantic Ocean. The authors discuss the sensitivity of the Arctic Ocean to long-term fixed extreme NAO states and show that the freshwater content of the Arctic is able to be restored to initial values from a depleted freshwater state after similar to 20 yr.
C1 [Condron, Alan; Hill, Chris] MIT, Dept Earth Atmospher & Planetary Sci, Cambridge, MA 02139 USA.
[Winsor, Peter] Univ Alaska Fairbanks, Sch Fisheries & Marine Sci, Fairbanks, AK USA.
[Menemenlis, Dimitris] CALTECH, Jet Prop Lab, Pasadena, CA USA.
RP Condron, A (reprint author), MIT, Dept Earth Atmospher & Planetary Sci, Cambridge, MA 02139 USA.
EM acondron@whoi.edu
NR 69
TC 29
Z9 29
U1 1
U2 9
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 MAY
PY 2009
VL 22
IS 9
BP 2422
EP 2437
DI 10.1175/2008JCLI2626.1
PG 16
WC Meteorology & Atmospheric Sciences
SC Meteorology & Atmospheric Sciences
GA 448TT
UT WOS:000266285600010
ER
PT J
AU Kwok, R
AF Kwok, R.
TI Outflow of Arctic Ocean Sea Ice into the Greenland and Barents Seas:
1979-2007
SO JOURNAL OF CLIMATE
LA English
DT Article
ID NORTH-ATLANTIC OSCILLATION; FRESH-WATER BALANCE; CIRCULATION; DECADES
AB Twenty-nine years of Arctic sea ice outflow into the Greenland and Barents Seas are summarized. Outflow is computed at three passages: Fram Strait, between Svalbard and Franz Josef Land (S-FJL), and between Franz Josef Land and Severnaya Zemlya (FJL-SZ). Ice drift at the flux gates has been reprocessed using a consistent and updated time series of passive microwave brightness temperature and ice concentration (IC) fields. Over the record, the mean annual area outflow at the Fram Strait is 706(113) x 10(3) km(2); it was highest in 1994/95 (1002 x 10(3) km(2)) when the North Atlantic Oscillation (NAO) index was near its 29-yr peak. The strength of the "Transpolar Drift Stream" (TDS) was high during the late 1980s through the mid-1990s. There is no statistically significant trend in the Fram Strait area flux. Even though there is a positive trend in the gradient of cross-strait sea level pressure, the outflow has not increased because of a negative trend in IC. Seasonally, the area outflow during recent summers (in 2005 and 2007) has been higher (> 2 sigma from the mean) than average, contributing to the decline of summer ice coverage. Without updated ice thickness estimates, the best estimate of mean annual volume flux (between 1991 and 1999) stands at similar to 2200 km(3) yr(-1) (similar to 0.07 Sv: Sv equivalent to 10(6) m(3) s(-1)). Net annual outflow at the S-FJL passage is 37(39) x 10(3) km(2); the large outflow of multiyear ice in 2002-03, marked by an area and volume outflow of 141 x 10(3) km(2) and similar to 300 km(3), was unusual over the record. At the FJL-SZ passage, there is a mean annual inflow of 103(93) x 10(3) km(2) of seasonal ice into the Arctic. While the recent pattern of winter Arctic circulation and sea level pressure (SLP) has nearly reverted to its conditions typical of the 1980s, the summer has not. Compared to the 1980s, the recent summer SLP distributions show much lower SLPs (2-3 hPa) over much of the Arctic. Overall, there is a strengthening of the summer TDS. Examination of the exchanges between the Pacific and Atlantic sectors shows a long-term trend that favors the summer advection of sea ice toward the Atlantic associated with a shift in the mean summer circulation patterns.
C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
RP Kwok, R (reprint author), CALTECH, Jet Prop Lab, MS 300-235,4800 Oak Grove Dr, Pasadena, CA 91109 USA.
EM ron.kwok@jpl.nasa.gov
RI Kwok, Ron/A-9762-2008
OI Kwok, Ron/0000-0003-4051-5896
FU National Science Foundation and the National Aeronautics and Space
Administration
FX I wish to thank S. S. Pang at JPL for her software support during the
preparation of this manuscript. The SMMR, SSM/I, and AMSR-E brightness
temperature and ice concentration fields are provided by World Data
Center A for Glaciology/National Snow and Ice Data Center, University of
Colorado, Boulder, Colorado. This work was carried out at the Jet
Propulsion Laboratory, California Institute of Technology, and is
sponsored by the National Science Foundation and the National
Aeronautics and Space Administration.
NR 33
TC 88
Z9 92
U1 1
U2 28
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 MAY
PY 2009
VL 22
IS 9
BP 2438
EP 2457
DI 10.1175/2008JCLI2819.1
PG 20
WC Meteorology & Atmospheric Sciences
SC Meteorology & Atmospheric Sciences
GA 448TT
UT WOS:000266285600011
ER
PT J
AU Wang, HL
Schubert, S
Suarez, M
Chen, JY
Hoerling, M
Kumar, A
Pegion, P
AF Wang, Hailan
Schubert, Siegfried
Suarez, Max
Chen, Junye
Hoerling, Martin
Kumar, Arun
Pegion, Philip
TI Attribution of the Seasonality and Regionality in Climate Trends over
the United States during 1950-2000
SO JOURNAL OF CLIMATE
LA English
DT Article
ID GENERAL-CIRCULATION MODELS; SPATIOTEMPORAL STRUCTURE; COUPLED MODEL;
SEA-ICE; PART I; SIMULATIONS; VARIABILITY; REANALYSES; US
AB The observed climate trends over the United States during 1950-2000 exhibit distinct seasonality and regionality. The surface air temperature exhibits a warming trend during winter, spring, and early summer and a modest countrywide cooling trend in late summer and fall, with the strongest warming occurring over the northern United States in spring. Precipitation trends are positive in all seasons, with the largest trend occurring over the central and southern United States in fall. This study investigates the causes of the seasonality and regionality of those trends, with a focus on the cooling and wetting trends in the central United States during late summer and fall. In particular, the authors examine the link between the seasonality and regionality of the climate trends over the United States and the leading patterns of sea surface temperature (SST) variability, including a global warming (GW) pattern and a Pacific decadal variability (PDV) pattern.
A series of idealized atmospheric general circulation model (AGCM) experiments were performed forced by SST trends associated with these leading SST patterns, as well as the residual trend pattern ( obtained by removing the GW and PDV contributions). The results show that the observed seasonal and spatial variations of the climate trends over the United States are to a large extent explained by changes in SST. Among the leading patterns of SST variability, the PDV pattern plays a prominent role in producing both the seasonality and regionality of the climate trends over the United States. In particular, it is the main contributor to the apparent cooling and wetting trends over the central United States. The residual SST trend, a manifestation of phase changes of the Atlantic multidecadal SST variation during 1950-2000, also exerts influences that show strong seasonality with important contributions to the central U. S. temperature and precipitation during the summer and fall seasons. In contrast, the response over the United States to the GW SST pattern is an overall warming with little seasonality or regional variation. These results highlight the important contributions of decadal and multidecadal variability in the Pacific and Atlantic in explaining the observed seasonality and regionality of the climate trends over the United States during the period of 1950-2000.
C1 [Wang, Hailan] Univ Maryland, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21201 USA.
[Chen, Junye] Univ Maryland, Earth Syst Sci Interdisciplinary Ctr, College Pk, MD 20742 USA.
[Kumar, Arun; Pegion, Philip] NOAA, Climate Predict Ctr, Natl Ctr Environm Predict, Boulder, CO USA.
RP Wang, HL (reprint author), NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off UMBC GEST, Code 610-1, Greenbelt, MD 20771 USA.
EM hailan.wang@nasa.gov
RI Chen, Junye/G-4301-2011; Pegion, Philip/E-5247-2012
FU NASA; Office of Science, U.S. Department of Energy
FX This study is supported by the NASA Modeling, Analysis, and Prediction (
MAP) project on Climate Transitions in the 1970s. We wish to acknowledge
the international modeling groups for providing their data for analysis,
the Program for Climate Model Diagnosis and Intercomparison (PCMDI) for
collecting and archiving the model data, the JSC/CLIVAR WGCM and their
Coupled Model Intercomparison Project (CMIP) and Climate Simulation
Panel for organizing the model data analysis activity, and the IPCC WG1
TSU for technical support. The IPCC Data Archive at Lawrence Livermore
National Laboratory is supported by the Office of Science, U.S.
Department of Energy. We thank two anonymous reviewers for their
constructive comments and suggestions, which led to many improvements in
the presentation of the results.
NR 40
TC 57
Z9 57
U1 1
U2 15
PU AMER METEOROLOGICAL SOC
PI BOSTON
PA 45 BEACON ST, BOSTON, MA 02108-3693 USA
SN 0894-8755
EI 1520-0442
J9 J CLIMATE
JI J. Clim.
PD MAY
PY 2009
VL 22
IS 10
BP 2571
EP 2590
DI 10.1175/2008JCLI2359.1
PG 20
WC Meteorology & Atmospheric Sciences
SC Meteorology & Atmospheric Sciences
GA 453CG
UT WOS:000266587200006
ER
PT J
AU Lin, WY
Zhang, MH
Loeb, NG
AF Lin, Wuyin
Zhang, Minghua
Loeb, Norman G.
TI Seasonal Variation of the Physical Properties of Marine Boundary Layer
Clouds off the California Coast
SO JOURNAL OF CLIMATE
LA English
DT Article
ID LOWER-TROPOSPHERIC STABILITY; STRATOCUMULUS; REANALYSIS; MODEL;
TEMPERATURE; TRANSITION; SATELLITE; DYNAMICS; ICOADS; ASTEX
AB Marine boundary layer (MBL) clouds can significantly regulate the sensitivity of climate models, yet they are currently poorly simulated. This study aims to characterize the seasonal variations of physical properties of these clouds and their associated processes by using multisatellite data. Measurements from several independent satellite datasets [ International Satellite Cloud Climatology Project (ISCCP), Clouds and the Earth's Radiant Energy System-Moderate Resolution Imaging Spectroradiometer (CERES-MODIS), Geoscience Laser Altimeter System (GLAS), and Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO)], in conjunction with balloon soundings from the mobile facility of the Atmospheric Radiation Measurement ( ARM) program at Point Reyes and reanalysis products, are used to characterize the seasonal variations of MBL cloud-top and cloud-base heights, cloud thickness, the degree of decoupling between clouds and MBL, and inversion strength off the California coast.
The main results from this study are as follows: (i) MBL clouds over the northeast subtropical Pacific in the summer are more prevalent and associated with a larger in-cloud water path than in winter. The cloud-top and cloud-base heights are lower in the summer than in the winter. (ii) Although the lower-tropospheric stability of the atmosphere is higher in the summer, the MBL inversion strength is only weakly stronger in the summer because of a negative feedback from the cloud-top altitude. Summertime MBL clouds are more homogeneous and are associated with lower surface latent heat flux than those in the winter. (iii) Seasonal variations of low-cloud properties from summer to winter resemble the downstream stratocumulus-to-cumulus transition of MBL clouds in terms of MBL depth, cloud-top and cloud-base heights, inversion strength, and spatial homogeneity. The "deepening-warming'' mechanism of Bretherton and Wyant for the stratocumulus-to-trade-cumulus transition downstream of the cold eastern ocean can also explain the seasonal variation of low clouds from the summer to the winter, except that warming of the sea surface temperature needs to be taken as relative to the free-tropospheric air temperature, which occurs in the winter. The observed variation of low clouds from summer to winter is attributed to the much larger seasonal cooling of the free-tropospheric air temperature than that of the sea surface temperature.
C1 [Lin, Wuyin; Zhang, Minghua] SUNY Stony Brook, Sch Marine & Atmospher Sci, Stony Brook, NY 11794 USA.
[Loeb, Norman G.] Hampton Univ, NASA, Langley Res Ctr, Hampton, VA 23668 USA.
RP Lin, WY (reprint author), SUNY Stony Brook, Sch Marine & Atmospher Sci, Stony Brook, NY 11794 USA.
EM wlin@atmsci.msrc.sunysb.edu
NR 35
TC 35
Z9 36
U1 0
U2 14
PU AMER METEOROLOGICAL SOC
PI BOSTON
PA 45 BEACON ST, BOSTON, MA 02108-3693 USA
SN 0894-8755
EI 1520-0442
J9 J CLIMATE
JI J. Clim.
PD MAY
PY 2009
VL 22
IS 10
BP 2624
EP 2638
DI 10.1175/2008JCLI2478.1
PG 15
WC Meteorology & Atmospheric Sciences
SC Meteorology & Atmospheric Sciences
GA 453CG
UT WOS:000266587200009
ER
PT J
AU Koch, D
Menon, S
Del Genio, A
Ruedy, R
Alienov, I
Schmidt, GA
AF Koch, Dorothy
Menon, Surabi
Del Genio, Anthony
Ruedy, Reto
Alienov, Igor
Schmidt, Gavin A.
TI Distinguishing Aerosol Impacts on Climate over the Past Century
SO JOURNAL OF CLIMATE
LA English
DT Article
ID BLACK CARBON; SULFATE AEROSOLS; GREENHOUSE-GAS; GISS MODELE; ICE-SHEET;
SIMULATION; SNOW; SENSITIVITY; PARAMETERIZATION; DEPOSITION
AB Aerosol direct ( DE), indirect (IE), and black carbon-snow albedo (BAE) effects on climate between 1890 and 1995 are compared using equilibrium aerosol-climate simulations in the Goddard Institute for Space Studies General Circulation Model coupled to a mixed layer ocean. Pairs of control (1890)-perturbation ( 1995) with successive aerosol effects allow isolation of each effect. The experiments are conducted both with and without concurrent changes in greenhouse gases (GHG). Anew scheme allowing dependence of snow albedo on black carbon snow concentration is introduced. The fixed GHG experiments global surface air temperature ( SAT) changed by -0.2 degrees, -1.0 degrees, and +0.2 degrees C from the DE, IE, and BAE. Ice and snow cover increased 1% from the IE and decreased 0.3% from the BAE. These changes were a factor of 4 larger in the Arctic. Global cloud cover increased by 0.5% from the IE. Net aerosol cooling effects are about half as large as the GHG warming, and their combined climate effects are smaller than the sum of their individual effects. Increasing GHG did not affect the IE impact on cloud cover, however they decreased aerosol effects on SAT by 20%, and on snow/ice cover by 50%; they also obscure the BAE on snow/ ice cover. Arctic snow, ice, cloud, and shortwave forcing changes occur mostly during summer-fall, but SAT, sea level pressure, and longwave forcing changes occur during winter. An explanation is that aerosols impact the cryosphere during the warm season but the associated SAT effect is delayed until winter.
C1 [Koch, Dorothy; Del Genio, Anthony; Alienov, Igor; Schmidt, Gavin A.] Columbia Univ, NASA, Goddard Inst Space Studies, New York, NY 10025 USA.
[Menon, Surabi] Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA.
[Ruedy, Reto] Sigma Space Partners, New York, NY USA.
RP Koch, D (reprint author), Columbia Univ, NASA, Goddard Inst Space Studies, 2880 Broadway, New York, NY 10025 USA.
EM dkoch@giss.nasa.gov
RI Del Genio, Anthony/D-4663-2012; Schmidt, Gavin/D-4427-2012
OI Del Genio, Anthony/0000-0001-7450-1359; Schmidt,
Gavin/0000-0002-2258-0486
FU Clean Air Task Force; NASA
FX We thank Stephen Warren for assistance in development of the model
BC-albedo parameterization. Support for this research is from the Clean
Air Task Force, the NASA Radiation Science Program, and the NASA
Modeling, Analysis, and Prediction Program.
NR 49
TC 68
Z9 68
U1 3
U2 23
PU AMER METEOROLOGICAL SOC
PI BOSTON
PA 45 BEACON ST, BOSTON, MA 02108-3693 USA
SN 0894-8755
EI 1520-0442
J9 J CLIMATE
JI J. Clim.
PD MAY
PY 2009
VL 22
IS 10
BP 2659
EP 2677
DI 10.1175/2008JCLI2573.1
PG 19
WC Meteorology & Atmospheric Sciences
SC Meteorology & Atmospheric Sciences
GA 453CG
UT WOS:000266587200011
ER
PT J
AU Wang, AH
Bohn, TJ
Mahanama, SP
Koster, RD
Lettenmaier, DP
AF Wang, Aihui
Bohn, Theodore J.
Mahanama, Sarith P.
Koster, Randal D.
Lettenmaier, Dennis P.
TI Multimodel Ensemble Reconstruction of Drought over the Continental
United States
SO JOURNAL OF CLIMATE
LA English
DT Article
ID CATCHMENT-BASED APPROACH; LAND-SURFACE PROCESSES; MESOSCALE ETA-MODEL;
SEVERITY INDEX; SOIL-MOISTURE; GREAT-PLAINS; CLIMATE; PARAMETERIZATION;
PRECIPITATION; DATASET
AB Retrospectively simulated soil moisture from an ensemble of six land surface/hydrological models was used to reconstruct drought events over the continental United States for the period 1920-2003. The simulations were performed at one-half-degree spatial resolution, using a common set of atmospheric forcing data and model-specific soil and vegetation parameters. Monthly simulated soil moisture was converted to percentiles using Weibull plotting position statistics, and the percentiles were then used to represent drought severities and durations. An ensemble method, based on an inverse mapping of the average of the individual model's soil moisture percentiles, was also used to combine all models' simulations. Major results are 1) all models and the ensemble reconstruct the known severe drought events during the last century. The spatial extents and severities of drought are plausible for the individual models although substantial among-model disparities exist. 2) The simulations are in more agreement with each other over the eastern than over the western United States. 3) Most of the models show that soil moisture memory is much longer over the western than over the eastern United States. The results provide some insights into how a hydrological nowcast system can be developed, and also early results from a test application within the University of Washington's real-time national Surface Water Monitor and a review of the multimodel nowcasts during the southeastern drought beginning in summer 2007 are included.
C1 [Wang, Aihui; Bohn, Theodore J.; Lettenmaier, Dennis P.] Univ Washington, Dept Civil & Environm Engn, Seattle, WA 98195 USA.
[Mahanama, Sarith P.; Koster, Randal D.] NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Greenbelt, MD 20771 USA.
RP Lettenmaier, DP (reprint author), Univ Washington, Dept Civil & Environm Engn, 164 Wilcox Hall,Box 352700, Seattle, WA 98195 USA.
EM dennisl@u.washington.edu
RI Koster, Randal/F-5881-2012; Bohn, Theodore/K-4494-2012; lettenmaier,
dennis/F-8780-2011
OI Koster, Randal/0000-0001-6418-6383; Bohn, Theodore/0000-0002-1880-9129;
lettenmaier, dennis/0000-0003-3317-1327
FU U.S. Department of Energy [DE-FG02-04ER63873]; Institute of Atmospheric
Physics [KZCX2-YW-217]
FX The work was supported by the U.S. Department of Energy under DOE
Agreement Number DE-FG02-04ER63873 to the University of Washington, and
the CAS Fund (KZCX2-YW-217) at the Institute of Atmospheric Physics. We
appreciate the assistance of Ben Livneh of the University of
NR 49
TC 80
Z9 85
U1 3
U2 14
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 MAY
PY 2009
VL 22
IS 10
BP 2694
EP 2712
DI 10.1175/2008JCLI2586.1
PG 19
WC Meteorology & Atmospheric Sciences
SC Meteorology & Atmospheric Sciences
GA 453CG
UT WOS:000266587200013
ER
PT J
AU Tessler, A
Di Sciuva, M
Gherlone, M
AF Tessler, Alexander
Di Sciuva, Marco
Gherlone, Marco
TI A Refined Zigzag Beam Theory for Composite and Sandwich Beams
SO JOURNAL OF COMPOSITE MATERIALS
LA English
DT Article; Proceedings Paper
CT 6th International Conference on Advanced Composites
CY MAY 16-18, 2007
CL Univ Patras, Corfu, GREECE
SP Greek Soc Composite Mat
HO Univ Patras
DE Timoshenko beam theory; zigzag kinematics; shear deformation; composite
beams; sandwich beams; virtual work principle
ID THICK LAMINATED BEAMS; DYNAMIC-RESPONSE; PLATES; SHEAR; SHELLS
AB A new refined theory for laminated composite and sandwich beams that contains the kinematics of the Timoshenko Beam Theory as a proper baseline subset is presented. This variationally consistent theory is derived from the virtual work principle and employs a novel piecewise linear zigzag function that provides a more realistic representation of the deformation states of transverse-shear flexible beams than other similar theories. This new zigzag function is unique in that it vanishes at the top and bottom bounding surfaces of a beam. The formulation does not enforce continuity of the transverse shear stress across the beam's cross-section, yet is robust. Two major shortcomings that are inherent in the previous zigzag theories, shear-force inconsistency and difficulties in simulating clamped boundary conditions, and that have greatly limited the utility of these previous theories are discussed in detail. An approach that has successfully resolved these shortcomings is presented herein. Exact solutions for simply supported and cantilevered beams subject to static loads are derived and the improved modelling capability of the new 'zigzag' beam theory is demonstrated. In particular, extensive results for thick beams with highly heterogeneous material lay-ups are discussed and compared with corresponding results obtained from elasticity solutions, two other 'zigzag' theories, and high-fidelity finite element analyses. Comparisons with the baseline Timoshenko Beam Theory are also presented. The comparisons clearly show the improved accuracy of the new, refined 'zigzag' theory presented herein over similar existing theories. This new theory can be readily extended to plate and shell structures, and should be useful for obtaining relatively low-cost, accurate estimates of structural response needed to design an important class of high-performance aerospace structures.
C1 [Di Sciuva, Marco; Gherlone, Marco] Politecn Torino, Dept Aeronaut & Space Engn, I-10129 Turin, Italy.
[Tessler, Alexander] NASA Langley Res Ctr, Struct Mech & Concepts Branch, Hampton, VA 23681 USA.
RP Gherlone, M (reprint author), Politecn Torino, Dept Aeronaut & Space Engn, Corso Duca Abruzzi 24, I-10129 Turin, Italy.
EM marco.gherlone@polito.it
RI Tessler, Alexander/A-4729-2009;
OI Gherlone, Marco/0000-0002-5711-0046
NR 24
TC 46
Z9 48
U1 2
U2 10
PU SAGE PUBLICATIONS LTD
PI LONDON
PA 1 OLIVERS YARD, 55 CITY ROAD, LONDON EC1Y 1SP, ENGLAND
SN 0021-9983
EI 1530-793X
J9 J COMPOS MATER
JI J. Compos Mater.
PD MAY
PY 2009
VL 43
IS 9
BP 1051
EP 1081
DI 10.1177/0021998308097730
PG 31
WC Materials Science, Composites
SC Materials Science
GA 437VF
UT WOS:000265514300010
ER
PT J
AU Yamaleev, NK
Carpenter, MH
AF Yamaleev, Nail K.
Carpenter, Mark H.
TI Third-order Energy Stable WENO scheme
SO JOURNAL OF COMPUTATIONAL PHYSICS
LA English
DT Article
DE High-order finite difference methods; Weighted essentially
non-oscillatory schemes; Energy estimate; Numerical stability;
Artificial dissipation
ID ESSENTIALLY NONOSCILLATORY SCHEMES; DISCONTINUOUS GALERKIN METHOD;
FINITE-DIFFERENCE APPROXIMATIONS; SCALAR CONSERVATION-LAWS; HIGH-ORDER;
UNSTRUCTURED GRIDS; ENTROPY INEQUALITY; HYPERBOLIC SYSTEMS; ACCURACY;
CONVERGENCE
AB A new third-order Energy Stable Weighted Essentially Non-Oscillatory (ESWENO) finite difference scheme for scalar and vector hyperbolic equations with piecewise continuous initial conditions is developed. The new scheme is proven to be linearly stable in the energy norm for both continuous and discontinuous solutions. In contrast to the existing high-resolution shock-capturing schemes, no assumption that the reconstruction should be total variation bounded (TVB) is explicitly required to prove stability of the new scheme. We also present new weight functions which drastically improve the accuracy of the third-order ESWENO scheme. Based on a truncation error analysis, we show that the ESWENO scheme is design-order accurate for smooth solutions with any number of vanishing derivatives, if its tuning parameters satisfy certain constraints. Numerical results show that the new ESWENO scheme is stable and significantly outperforms the conventional third-order WENO scheme of Jiang and Shu in terms of accuracy, while providing essentially non-oscillatory solutions near strong discontinuities. (C) 2009 Elsevier Inc. All rights reserved.
C1 [Yamaleev, Nail K.] N Carolina Agr & Tech State Univ, Dept Math, Greensboro, NC 27411 USA.
[Carpenter, Mark H.] NASA, Langley Res Ctr, Computat Aerosci Branch, Hampton, VA 23681 USA.
RP Yamaleev, NK (reprint author), N Carolina Agr & Tech State Univ, Dept Math, Greensboro, NC 27411 USA.
EM nkyamale@ncat.edu
FU Army Research Laboratory [W911NF-06-R-006]
FX The work of the first author was supported in part by the Army Research
Laboratory under Grant W911NF-06-R-006.
NR 35
TC 30
Z9 31
U1 1
U2 11
PU ACADEMIC PRESS INC ELSEVIER SCIENCE
PI SAN DIEGO
PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA
SN 0021-9991
EI 1090-2716
J9 J COMPUT PHYS
JI J. Comput. Phys.
PD MAY 1
PY 2009
VL 228
IS 8
BP 3025
EP 3047
DI 10.1016/j.jcp.2009.01.011
PG 23
WC Computer Science, Interdisciplinary Applications; Physics, Mathematical
SC Computer Science; Physics
GA 426CK
UT WOS:000264685000018
ER
PT J
AU Calle, CI
Buhler, CR
McFall, JL
Snyder, SJ
AF Calle, C. I.
Buhler, C. R.
McFall, J. L.
Snyder, S. J.
TI Particle removal by electrostatic and dielectrophoretic forces for dust
control during lunar exploration missions
SO JOURNAL OF ELECTROSTATICS
LA English
DT Article
CT 11th International Conference on Electrostatics
CY MAY 27-29, 2009
CL Valencia, SPAIN
SP Inst Elect Technol, Polytech Univ Valencia
DE Dielectrophoretic forces; Electric fields; Particle charging; Space
applications
ID FIELD
AB Particle removal during lunar exploration activities is of prime importance for the Success of robotic and human exploration of the moon. We report on our efforts to use electrostatic and dielectrophoretic forces to develop a dust removal technology that prevents the accumulation of dust oil solar panels and removes dust adhering to those surfaces. Testing of several prototypes showed solar shield output above 90% of the initial potentials after dust clearing. Published by Elsevier B.V.
C1 [Calle, C. I.] NASA, Electrostat & Surface Phys Lab, Kennedy Space Ctr, FL 32899 USA.
[Buhler, C. R.; McFall, J. L.; Snyder, S. J.] ASRC Aerosp, Kennedy Space Ctr, FL 32899 USA.
RP Calle, CI (reprint author), NASA, Electrostat & Surface Phys Lab, Kennedy Space Ctr, FL 32899 USA.
EM carlos.i.calle@nasa.gov
NR 17
TC 43
Z9 47
U1 1
U2 17
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0304-3886
J9 J ELECTROSTAT
JI J. Electrost.
PD MAY
PY 2009
VL 67
IS 2-3
BP 89
EP 92
DI 10.1016/j.elstat.2009.02.012
PG 4
WC Engineering, Electrical & Electronic
SC Engineering
GA 444ZN
UT WOS:000266019500004
ER
PT J
AU Buhler, C
Calle, C
Clements, JS
Trigwell, S
Ritz, M
AF Buhler, Charles
Calle, Carlos
Clements, J. S.
Trigwell, Steven
Ritz, Mindy
TI New techniques to evaluate the incendivity of insulators
SO JOURNAL OF ELECTROSTATICS
LA English
DT Article
CT 11th International Conference on Electrostatics
CY MAY 27-29, 2009
CL Valencia, SPAIN
SP Inst Elect Technol, Polytech Univ Valencia
DE Incendivity; Safety and hazards; Incendiary behavior; Brush discharges;
Insulators; Flammable atmospheres
AB New techniques for evaluating the incendiary behavior of insulators is presented. The onset of incendive brush discharges in air is evaluated using standard spark probe techniques for the case Simulating approaches of all electrically grounded sphere to a charged insulator in the presence of a flammable atmosphere. However, this standard technique is unsuitable for the case of brush discharges that may occur during the charging-separation process for two insulator materials. We present experimental techniques to evaluate this hazard in the presence of a flammable atmosphere which is ideally suited to measure the incendiary nature of micro-discharges upon separation, a measurement never before performed. Other measurement techniques unique to this study include: Surface potential measurements of insulators before, during and after contact and separation, as well as methods to verify fieldmeter calibrations using a charge insulator surface opposed to standard high voltage plates. (C) 2009 Elsevier B.V. All rights reserved.
C1 [Buhler, Charles; Trigwell, Steven; Ritz, Mindy] ASRC Aerosp, Electrostat & Surface Phys Lab, Kennedy Space Ctr, FL 32899 USA.
[Calle, Carlos] NASA, Electrostat & Surface Phys Lab, Kennedy Space Ctr, FL 32899 USA.
[Clements, J. S.] Appalachian State Univ, Dept Phys & Astron, Boone, NC 28608 USA.
RP Buhler, C (reprint author), ASRC Aerosp, Electrostat & Surface Phys Lab, Kennedy Space Ctr, FL 32899 USA.
EM charles.r.buhler@nasa.gov; carlos.i.calle@nasa.gov;
clementsjs@appstate.edu; steven.trigwell-1@nasa.gov
NR 14
TC 1
Z9 1
U1 0
U2 0
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0304-3886
J9 J ELECTROSTAT
JI J. Electrost.
PD MAY
PY 2009
VL 67
IS 2-3
BP 285
EP 290
DI 10.1016/j.elstat.2009.01.017
PG 6
WC Engineering, Electrical & Electronic
SC Engineering
GA 444ZN
UT WOS:000266019500040
ER
PT J
AU Scott, JH
AF Scott, John H.
TI Fuel Cell Development for NASA's Human Exploration Program: Benchmarking
With "The Hydrogen Economy"
SO JOURNAL OF FUEL CELL SCIENCE AND TECHNOLOGY
LA English
DT Article
CT 2nd European Fuel Cell Technology and Applications Conference
CY DEC, 2007
CL Rome, ITALY
DE fuel cell power plants; fuel cell vehicles; hydrogen economy; life cycle
costing
AB The theoretically high efficiency and low temperature operation of hydrogen-oxygen fuel cells have motivated them to be the subject of much study since their invention in the 19th century, but their relatively high life cycle costs have kept them as a "solution in search of a problem" for many years. The first problem for which fuel cells presented a truly cost effective solution was that of providing a power source for NASA's human spaceflight vehicles in the 1960s. NASA thus invested, and continues to invest, in the development of fuel cell power plants for this application. This development program continues to place its highest priorities on requirements for minimum system mass and maximum durability and reliability. These priorities drive fuel cell power plant design decisions at all levels, even that of catalyst support. However, since the mid-1990s, prospective environmental regulations have driven increased governmental and industrial interest in "green power" and "the hydrogen economy." This has in turn stimulated greatly increased investment in fuel cell development for a variety of commercial applications. This investment is bringing about notable advances in fuel cell technology, but as these development efforts place their highest priority on requirements for minimum life cycle cost and field safety, these advances are yielding design solutions quite different at almost every level from those needed for spacecraft applications. This environment thus presents both opportunities and challenges for NASA's Human Exploration program.
C1 NASA, Lyndon B Johnson Space Ctr EP3, Div Energy Syst, Houston, TX 77058 USA.
RP Scott, JH (reprint author), NASA, Lyndon B Johnson Space Ctr EP3, Div Energy Syst, Houston, TX 77058 USA.
EM john.h.scott@nasa.gov
NR 7
TC 1
Z9 1
U1 1
U2 7
PU ASME-AMER SOC MECHANICAL ENG
PI NEW YORK
PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA
SN 1550-624X
J9 J FUEL CELL SCI TECH
JI J. Fuel Cell Sci. Technol.
PD MAY
PY 2009
VL 6
IS 2
AR 021011
DI 10.1115/1.2972170
PG 7
GA 416SD
UT WOS:000264024900012
ER
PT J
AU Bezard, B
Tsang, CCC
Carlson, RW
Piccioni, G
Marcq, E
Drossart, P
AF Bezard, Bruno
Tsang, Constantine C. C.
Carlson, Robert W.
Piccioni, Giuseppe
Marcq, Emmanuel
Drossart, Pierre
TI Water vapor abundance near the surface of Venus from Venus
Express/VIRTIS observations
SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
LA English
DT Article
ID LOWER ATMOSPHERE; DEEP ATMOSPHERE; SPECTRA; NIGHTSIDE; GALILEO; PROBES;
SIDE
AB Nightside observations of the 1.18-mu m atmospheric window by the Visible and Infrared Thermal Imaging Spectrometer (VIRTIS) aboard the Venus Express spacecraft were analyzed to measure and map the water vapor abundance in the lower atmosphere. Thermal emission in this window originates partly from the surface and partly from the first scale height (0-15 km) of the atmosphere. Constraints on the CO(2) continuum absorption, which is the dominant source of gaseous opacity in the window, were obtained from the variation of the 1.185-mu m intensity with surface elevation. An absorption coefficient of 1 +/- 0.4 x 10(-9) cm(-1) amagat(-2) best fits the observed variation. We retrieved a water vapor mole fraction of 44 +/- 9 ppm from various selections of VIRTIS spectra in the southern hemisphere, in agreement with previous analyses of the nightside emission. This value is somewhat larger than that previously determined at higher altitudes from the 2.3- and 1.74-mu m nightside windows, but the error bars still allow a constant with height H(2)O mole fraction from the surface up to 40 km. Using the intensity ratio in the two wings of the 1.18-mm window as a proxy, we searched for horizontal variations of the H2O abundance in various VIRTIS observational sequences. We derived stringent upper limits for any possible latitudinal variations on the night side: +/- 1.5% in the range 60 degrees S-25 degrees N and +/- 3% for the broader range 80 degrees S-25 degrees N. The lack of detectable latitudinal variations is consistent with a constant with height water profile in the lower atmosphere and probably precludes any strong concentration gradient near the surface.
C1 [Bezard, Bruno; Marcq, Emmanuel; Drossart, Pierre] Univ Paris Diderot, UPMC, CNRS, Observ Paris,LESIA, F-92190 Meudon, France.
[Tsang, Constantine C. C.] Univ Oxford, Dept Phys, Clarendon Lab, Oxford OX1 3PU, England.
[Carlson, Robert W.] Jet Prop Lab, Pasadena, CA 91109 USA.
[Piccioni, Giuseppe] IASF, INAF, I-00133 Rome, Italy.
RP Bezard, B (reprint author), Univ Paris Diderot, UPMC, CNRS, Observ Paris,LESIA, 5 Pl Jules Janssen, F-92190 Meudon, France.
EM Bruno.Bezard@obspm.fr
OI Piccioni, Giuseppe/0000-0002-7893-6808
FU Centre National d'Etudes Spatiales (CNES); Agenzia Spaziale Italiana
(ASI)
FX B. B., E. M., and P. D. acknowledge support from Centre National
d'Etudes Spatiales (CNES). G. P. was supported by Agenzia Spaziale
Italiana (ASI). We gratefully thank the VIRTIS technical team for their
continuous support.
NR 24
TC 39
Z9 39
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 MAY 1
PY 2009
VL 114
AR E00B39
DI 10.1029/2008JE003251
PG 12
WC Geochemistry & Geophysics
SC Geochemistry & Geophysics
GA 440BE
UT WOS:000265672000001
ER
PT J
AU Xue, M
Kopardekar, P
AF Xue, Min
Kopardekar, Parimal
TI High-Capacity Tube Network Design Using the Hough Transform
SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS
LA English
DT Article; Proceedings Paper
CT AIAA Guidance, Navigation, and Control Conference
CY AUG 17-20, 2008
CL Honolulu, HI
SP AIAA
AB A new airspace design concept, tube networks, could enable high-density operations with less air traffic control workload. To construct tubes optimally, it is necessary to identify the commonality of flight trajectories. This paper proposes a new strategy to cluster great circle flight trajectories for forming tubes. The Hough transform is applied to identify groups or clusters of great circle trajectories that could form the tube networks. The genetic algorithm is then applied to optimize the tube network. Results show that small deviations from great circle routes could yield tubes that accommodate significant traffic levels within feasible computational time.
C1 [Xue, Min] Univ Calif Santa Cruz, Moffett Field, CA 94035 USA.
[Kopardekar, Parimal] NASA, Ames Res Ctr, Automat Concepts Branch, Moffett Field, CA 94035 USA.
RP Xue, M (reprint author), Univ Calif Santa Cruz, Mail Stop 210-10, Moffett Field, CA 94035 USA.
EM Min.Xue@nasa.gov; Parimal.H.Kopardekar@nasa.gov
NR 11
TC 5
Z9 6
U1 0
U2 0
PU AMER INST AERONAUT ASTRONAUT
PI RESTON
PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA
SN 0731-5090
J9 J GUID CONTROL DYNAM
JI J. Guid. Control Dyn.
PD MAY-JUN
PY 2009
VL 32
IS 3
BP 788
EP 795
DI 10.2514/1.40386
PG 8
WC Engineering, Aerospace; Instruments & Instrumentation
SC Engineering; Instruments & Instrumentation
GA 445NL
UT WOS:000266057400008
ER
PT J
AU Grabbe, S
Sridhar, B
Mukherjee, A
AF Grabbe, Shon
Sridhar, Banavar
Mukherjee, Avijit
TI Sequential Traffic Flow Optimization with Tactical Flight Control
Heuristics
SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS
LA English
DT Article; Proceedings Paper
CT AIAA Guidance, Navigation, and Control Conference
CY AUG 18-21, 2008
CL Honolulu, HI
SP Amer Inst Aeronaut & Astronaut (AIAA)
AB A sequential optimization method is applied to manage air traffic flow under uncertainty in airspace capacity and demand. To support its testing, a decision support system is developed by integrating a deterministic integer programming model for assigning delays to aircraft under en route capacity constraints with a fast-time simulation environment to reactively account for system uncertainties. To reduce computational complexity, the model assigns only departure controls, and a tactical control loop consisting of a shortest-path routing algorithm and an airbornedelay algorithm refines the strategic plan to keep flights from deviating into capacity-constrained airspace. This integrated approach was used to conduct 32 six-hour fast-time simulation experiments to explore variations in the number and severity of departure controls, tactical reroutes, and airborne-delay controls. These experiments highlighted a fundamental difference in the manner in which weather translation is performed at the strategic and tactical levels. Although tactical weather translation explicitly accounts for the direct impact of weather on individual flights, strategic weather translation, which is accomplished by calculating a reduced capacity fora region of airspace such as a sector, typically fails to account for these flow-based impacts. Finally, an initial validation of the rerouting algorithm, which was the dominant control strategy for avoiding en route weather in the experiments, indicates that the algorithm is able to generate reroutes that are, on average, shorter than operationally flown weather-avoidance routes, when regions of airspace that flights are likely to avoid are identified using the convective-weather-avoidance model.
C1 [Grabbe, Shon] NASA, Ames Res Ctr, Automat Concepts Res Branch, Moffett Field, CA 94035 USA.
[Sridhar, Banavar] NASA, Ames Res Ctr, Aviat Syst Div, Moffett Field, CA 94035 USA.
[Mukherjee, Avijit] Univ Calif Santa Cruz, Moffett Field, CA 94035 USA.
RP Grabbe, S (reprint author), NASA, Ames Res Ctr, Automat Concepts Res Branch, Mail Stop 210-10, Moffett Field, CA 94035 USA.
EM shon.r.grabbe@nasa.gov
NR 27
TC 10
Z9 10
U1 0
U2 3
PU AMER INST AERONAUT ASTRONAUT
PI RESTON
PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA
SN 0731-5090
J9 J GUID CONTROL DYNAM
JI J. Guid. Control Dyn.
PD MAY-JUN
PY 2009
VL 32
IS 3
BP 810
EP 820
DI 10.2514/1.40300
PG 11
WC Engineering, Aerospace; Instruments & Instrumentation
SC Engineering; Instruments & Instrumentation
GA 445NL
UT WOS:000266057400010
ER
PT J
AU Morelli, EA
AF Morelli, Eugene A.
TI Flight-Test Experiment Design for Characterizing Stability and Control
of Hypersonic Vehicles
SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS
LA English
DT Article; Proceedings Paper
CT United States Air Force T&E Days Conference 2008
CY FEB 05-07, 2008
CL Los Angeles, CA
AB A maneuver design method that is particularly well suited for determining the stability and control characteristics of hypersonic vehicles is described in detail. Analytical properties of the maneuver design are explained. The importance of these analytical properties for maximizing information content in flight data is discussed, along with practical implementation issues. Results from flight tests of the X-43A hypersonic research vehicle (also called Hyper-X) are used to demonstrate the excellent modeling results obtained using this maneuver design approach. A detailed design procedure for generating the maneuvers is given to allow application to other flight-test programs.
C1 NASA, Langley Res Ctr, Dynam Syst & Control Branch, Hampton, VA 23681 USA.
RP Morelli, EA (reprint author), NASA, Langley Res Ctr, Dynam Syst & Control Branch, Mail Stop 308, Hampton, VA 23681 USA.
NR 10
TC 16
Z9 19
U1 2
U2 16
PU AMER INST AERONAUT ASTRONAUT
PI RESTON
PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA
SN 0731-5090
J9 J GUID CONTROL DYNAM
JI J. Guid. Control Dyn.
PD MAY-JUN
PY 2009
VL 32
IS 3
BP 949
EP 959
DI 10.2514/1.37092
PG 11
WC Engineering, Aerospace; Instruments & Instrumentation
SC Engineering; Instruments & Instrumentation
GA 445NL
UT WOS:000266057400022
ER
PT J
AU Gyekenyesi, AL
Martin, RE
Morscher, GN
Owen, RB
AF Gyekenyesi, Andrew L.
Martin, Richard E.
Morscher, Gregory N.
Owen, Robert B.
TI Impedance-based Structural Health Monitoring of a Ceramic Matrix
Composite
SO JOURNAL OF INTELLIGENT MATERIAL SYSTEMS AND STRUCTURES
LA English
DT Article
DE structural health monitoring; ceramic matrix composite; piezoelectric
patch; SiC/SiC; thermal protection system; aerospace
ID TRANSDUCERS; SENSORS; DAMAGE
AB This article addresses the use of electro-mechanical impedance-based structural health monitoring for assessing damage in a woven ceramic matrix composite consisting of a silicon carbide fibers and silicon carbide matrix. Controlled levels of damage were induced by conducting quasi-static, load/unload/reload tensile tests. The specimen's localized mechanical impedance was assessed using piezoelectric-ceramic patches that act as both actuator and sensor. The impedance results were correlated to damage and compared to acoustic emissions data, stress-strain response, and data from previous studies concerning the material system. The impedance data was shown to correlate well with the progressive damage mechanisms within the composite material system.
C1 [Gyekenyesi, Andrew L.; Morscher, Gregory N.] NASA, GRC, Ohio Aerosp Inst, Cleveland, OH 44135 USA.
[Martin, Richard E.] Cleveland State Univ, NASA, GRC, Cleveland, OH 44135 USA.
[Owen, Robert B.] Extreme Diagnost Inc, Boulder, CO 80302 USA.
RP Gyekenyesi, AL (reprint author), NASA, GRC, Ohio Aerosp Inst, 21000 Brookpk Rd,MS 6-1, Cleveland, OH 44135 USA.
EM andrew.l.gyekenyesi@grc.nasa.gov
NR 22
TC 4
Z9 4
U1 1
U2 3
PU SAGE PUBLICATIONS LTD
PI LONDON
PA 1 OLIVERS YARD, 55 CITY ROAD, LONDON EC1Y 1SP, ENGLAND
SN 1045-389X
J9 J INTEL MAT SYST STR
JI J. Intell. Mater. Syst. Struct.
PD MAY
PY 2009
VL 20
IS 7
BP 875
EP 882
DI 10.1177/1045389X08099033
PG 8
WC Materials Science, Multidisciplinary
SC Materials Science
GA 446FV
UT WOS:000266107100009
ER
PT J
AU Washer, G
Brooks, T
Saulsberry, R
AF Washer, Glenn
Brooks, Thomas
Saulsberry, Regor
TI Characterization of Kevlar Using Raman Spectroscopy
SO JOURNAL OF MATERIALS IN CIVIL ENGINEERING
LA English
DT Article
ID DEFORMATION-BEHAVIOR; FIBERS; COMPOSITES; TEREPHTHALAMIDE); POLYMER
AB This paper explores the characterization of Kevlar composite materials using Raman spectroscopy. The goal of the research is to develop and understand the Raman spectrum of Kevlar materials to provide a foundation for the development of nondestructive evaluation (NDE) technologies based on the interaction of laser light with the polymer Kevlar. The paper discusses the fundamental aspects of experimental characterization of the spectrum of Kevlar, including the effects of incident wavelength, polarization, and laser power. The effects of environmental exposure of Kevlar materials on certain characteristics of its Raman spectrum are explored. These data may provide a foundation for the development of NDE technologies intended to detect the in situ deterioration of Kevlar materials used for engineering applications that can later be extended to other materials such as carbon fiber composites.
C1 [Washer, Glenn; Brooks, Thomas] Univ Missouri, Dept Civil & Environm Engn, Columbia, MO 65211 USA.
[Saulsberry, Regor] NASA White Sands Test Facil, Las Cruces, NM 88012 USA.
RP Washer, G (reprint author), Univ Missouri, Dept Civil & Environm Engn, 2503 Lafferre Hall, Columbia, MO 65211 USA.
NR 24
TC 7
Z9 9
U1 1
U2 22
PU ASCE-AMER SOC CIVIL ENGINEERS
PI RESTON
PA 1801 ALEXANDER BELL DR, RESTON, VA 20191-4400 USA
SN 0899-1561
J9 J MATER CIVIL ENG
JI J. Mater. Civ. Eng.
PD MAY
PY 2009
VL 21
IS 5
BP 226
EP 234
DI 10.1061/(ASCE)0899-1561(2009)21:5(226)
PG 9
WC Construction & Building Technology; Engineering, Civil; Materials
Science, Multidisciplinary
SC Construction & Building Technology; Engineering; Materials Science
GA 433WL
UT WOS:000265236400005
ER
PT J
AU Capo-Lugo, PA
Bainum, PM
AF Capo-Lugo, Pedro A.
Bainum, Peter M.
TI DEPLOYMENT PROCEDURE FOR THE TETRAHEDRON CONSTELLATION
SO JOURNAL OF MECHANICS OF MATERIALS AND STRUCTURES
LA English
DT Article
DE discrete linear quadratic regulator; impulse maneuvers; deployment
procedure; tetrahedron constellation
ID GAUSS PSEUDOSPECTRAL METHOD; DISTANCE CONSTRAINTS
AB The NASA Benchmark Tetrahedron Constellation is a four-satellite formation that requires a nominal separation distance at every apogee point. The deployment procedure of a tetrahedron constellation is complex and depends on the separation distance between any pair of satellites within the constellation. In this paper, the deployment procedure of the tetrahedron constellation will be divided into two stages: the deployment from a circular parking orbit to an elliptical orbit, and the correction of the separation distance between pairs of satellites within the constellation. The solution of this problem will be implemented with a combination of Hohmann transfer maneuvers and the digital linear quadratic regulator control scheme showing a minimum consumption of fuel. In summary, the combination of these two techniques will provide a different approach to the deployment procedure of the NASA benchmark tetrahedron constellation.
C1 [Capo-Lugo, Pedro A.; Bainum, Peter M.] Howard Univ, Dept Mech Engn, Washington, DC 20059 USA.
RP Capo-Lugo, PA (reprint author), NASA, George C Marshall Space Flight Ctr, Guidance Nav & Control Syst Design & Anal Branch, EV41, Huntsville, AL 35812 USA.
EM pcapo@howard.edu; pbainum@fac.howard.edu
FU Alliances for Graduate Education and Professoriate (AGEP) Program
FX Research supported by Alliances for Graduate Education and Professoriate
(AGEP) Program.
NR 15
TC 1
Z9 1
U1 0
U2 3
PU MATHEMATICAL SCIENCE PUBL
PI BERKELEY
PA UNIV CALIFORNIA, DEPT MATHEMATICS, BERKELEY, CA 94720-3840 USA
SN 1559-3959
J9 J MECH MATER STRUCT
JI J. Mech. Mater. Struct.
PD MAY
PY 2009
VL 4
IS 5
SI SI
BP 837
EP 854
DI 10.2140/jomms.2009.4.837
PG 18
WC Materials Science, Multidisciplinary; Mechanics
SC Materials Science; Mechanics
GA 505VR
UT WOS:000270727700005
ER
PT J
AU Kopasakis, G
DeLaat, JC
Chang, CT
AF Kopasakis, George
DeLaat, John C.
Chang, Clarence T.
TI Adaptive Instability Suppression Controls Method for Aircraft Gas
Turbine Engine Combustors
SO JOURNAL OF PROPULSION AND POWER
LA English
DT Article
ID ACTIVE CONTROL
AB An adaptive controls method for instability suppression in gas-turbine engine combustors has been developed and successfully tested with a realistic aircraft engine combustor rig. This testing was part of a program that demonstrated, for the first time, successful active combustor instability control in an aircraft gas-turbine enginelike environment. The controls method is called adaptive sliding phasor averaged control. Testing of the control method has been conducted in an experimental rig with different configurations designed to simulate combustors with instabilities of about 530 and 315 Hz. Results demonstrate the effectiveness of this method in suppressing combustor instabilities. In addition, a dramatic improvement in suppression of the instability was achieved by focusing control on the second harmonic of the instability. This is believed to be due to coupling in the form of energy exchange between different frequency modes in the combustor. These results may have implications for future research in combustor instability control.
C1 [Kopasakis, George; DeLaat, John C.] NASA, John H Glenn Res Ctr Lewis Field, Controls & Dynam Branch, Cleveland, OH 44135 USA.
[Chang, Clarence T.] NASA, John H Glenn Res Ctr Lewis Field, Combust Branch, Cleveland, OH 44135 USA.
RP Kopasakis, G (reprint author), NASA, John H Glenn Res Ctr Lewis Field, Controls & Dynam Branch, 21000 Brookpk Rd, Cleveland, OH 44135 USA.
NR 36
TC 3
Z9 3
U1 0
U2 2
PU AMER INST AERONAUTICS ASTRONAUTICS
PI RESTON
PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA
SN 0748-4658
EI 1533-3876
J9 J PROPUL POWER
JI J. Propul. Power
PD MAY-JUN
PY 2009
VL 25
IS 3
BP 618
EP 627
DI 10.2514/1.36777
PG 10
WC Engineering, Aerospace
SC Engineering
GA 452AX
UT WOS:000266513100008
ER
PT J
AU Longmier, BW
Reid, BM
Gallimore, AD
Chang-Diaz, FR
Squire, JP
Glover, TW
Chavers, G
Bering, EA
AF Longmier, Benjamin W.
Reid, Bryan M.
Gallimore, Alec D.
Chang-Diaz, Franklin R.
Squire, Jared P.
Glover, Tim W.
Chavers, Greg
Bering, Edgar A., III
TI Validating a Plasma Momentum Flux Sensor to an Inverted Pendulum Thrust
Stand
SO JOURNAL OF PROPULSION AND POWER
LA English
DT Article; Proceedings Paper
CT AIAA/ASME/SAE/ASEE 44th Joint Propulsion Conference and Exhibit
CY JUL 20-23, 2008
CL Hartford, CT
SP AIAA, ASME, SAE, ASEE
ID INSTRUMENT
AB The accuracy of a plasma impact force sensor was compared with that of the more commonly used inverted pendulum thrust stand using a 5 kW Xe Hall effect thruster. An improved plasma momentum flux sensor was designed and constructed based on a previous design. Real-time force measurements were made with both the plasma momentum flux sensor and the inverted pendulum thrust stand. The plasma momentum flux sensor measured the force exerted onto it by the Hall effect thruster exhaust plume with a resolution of 0.1 mN and an average discrepancy of 2% compared with thrust stand measurements. Experiments were completed using a 9 m by 6 m cylindrical vacuum chamber. The total force from the Hall effect thruster was modulated from 34 to 356 mN by varying both the anode voltage, from 150 to 500 V, and the neutral Xe gas flow rate, from 5 to 15 mg/s.
C1 [Longmier, Benjamin W.; Bering, Edgar A., III] Univ Houston, Dept Phys, Houston, TX 77204 USA.
[Reid, Bryan M.] Univ Michigan, Ann Arbor, MI 48109 USA.
[Chang-Diaz, Franklin R.; Squire, Jared P.; Glover, Tim W.] Ad Astra Rocket Co, Webster, TX 77598 USA.
[Chavers, Greg] NASA, George C Marshall Space Flight Ctr, Mission Operat Lab, Huntsville, AL 35812 USA.
RP Longmier, BW (reprint author), Univ Houston, Dept Phys, 141 W Bay Area Blvd, Houston, TX 77204 USA.
NR 17
TC 18
Z9 18
U1 1
U2 10
PU AMER INST AERONAUT ASTRONAUT
PI RESTON
PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA
SN 0748-4658
J9 J PROPUL POWER
JI J. Propul. Power
PD MAY-JUN
PY 2009
VL 25
IS 3
BP 746
EP 752
DI 10.2514/1.35706
PG 7
WC Engineering, Aerospace
SC Engineering
GA 452AX
UT WOS:000266513100021
ER
PT J
AU Frederick, RA
Whitehead, JJ
AF Frederick, Robert A., Jr.
Whitehead, J. Joshua
TI Predicting Hybrid Propellant Regression Rate Using Response Surfaces
SO JOURNAL OF PROPULSION AND POWER
LA English
DT Article; Proceedings Paper
CT AIAA/ASME/SAE/ASEE 41st Joint Propulsion Conference
CY JUL 10-13, 2005
CL Tucson, AZ
SP AIAA, ASME, SAE, ASEE
AB Applied mixture theory allows for estimation of propellant characteristics (such as regression rate or specific impulse) over an extended range of formulations from a limited number of tests. A mixed-oxidizer hybrid system was tested using fuel formulations of 25-30% ammonium perchlorate, 0-5% iron oxide, and 70-75% hydroxyl-terminated polybutadiene fired with gaseous oxygen. Through application of a reduced form of the cubic response equation, functional relationships were developed that correlate fuel composition to regression rate in the form of a three-dimensional response surface. The maximum regression rate was then estimated to occur at approximately 2% iron oxide and 27.5% ammonium perchlorate based on the response surface developed from experimental results at an oxidizer flux of 0.3 Ib(m)/in(2).s (0.211 kg/m(2).s) and a chamber pressure of 350 psia (2.41 MPa).
C1 [Frederick, Robert A., Jr.] Univ Alabama, Propul Res Ctr, Huntsville, AL 35899 USA.
[Whitehead, J. Joshua] NASA, George C Marshall Space Flight Ctr, ATK Launch Syst, Huntsville, AL 35812 USA.
RP Frederick, RA (reprint author), Univ Alabama, Propul Res Ctr, 5000 Technol Dr, Huntsville, AL 35899 USA.
NR 8
TC 2
Z9 2
U1 0
U2 2
PU AMER INST AERONAUT ASTRONAUT
PI RESTON
PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA
SN 0748-4658
J9 J PROPUL POWER
JI J. Propul. Power
PD MAY-JUN
PY 2009
VL 25
IS 3
BP 815
EP 818
DI 10.2514/1.14418
PG 4
WC Engineering, Aerospace
SC Engineering
GA 452AX
UT WOS:000266513100029
ER
PT J
AU Johnston, CO
Gnoffo, PA
Sutton, K
AF Johnston, Christopher O.
Gnoffo, Peter A.
Sutton, Kenneth
TI Influence of Ablation on Radiative Heating for Earth Entry
SO JOURNAL OF SPACECRAFT AND ROCKETS
LA English
DT Article; Proceedings Paper
CT AIAA 40th Thermophysics Conference
CY JUN 23-26, 2008
CL Seattle, WA
SP AIAA
ID CHEMICAL-KINETIC PROBLEMS; LUNAR-RETURN CONDITIONS; SHOCK-LAYER
RADIATION; FUTURE NASA MISSIONS; COUPLED RADIATION; SPALLED PARTICLES;
NONEQUILIBRIUM; CAPSULE; FLOWFIELD; INJECTION
AB Using the coupled ablation and radiation capability recently included in the LAURA flowfield solver, this paper investigates the influence of ablation on the shock-layer radiative heating for Earth entry. The extension of the HARA radiation model, which provides the radiation predictions in LAURA, to treat a gas consisting of the elements carbon, hydrogen, oxygen, and nitrogen is discussed. It is shown that the absorption coefficient of air is increased with the introduction of the carbon and hydrogen elements. A simplified shock-layer model is studied to show the impact of temperature, as well as the abundance of carbon and hydrogen, on the net absorption or emission from an ablation contaminated boundary layer. It is found that the ablation species reduce the radiative flux in the vacuum ultraviolet, through increased absorption, for all temperatures. However, in the infrared region of the spectrum, the ablation species increase the radiative flux, through strong emission, for temperatures above 3000 K. Thus, depending on the temperature and abundance of ablation species, the contaminated boundary layer may either provide a net increase or decrease in the radiative flux reaching the wall. To assess the validity of the coupled ablation and radiation LAURA analysis, a previously analyzed Mars-return case (15.24 km/s), which contains significant ablation and radiation coupling, is studied. Exceptional agreement with previous viscous-shock-layer results is obtained. A 40% decrease in the radiative flux is predicted for ablation rates equal to 20% of the freestream mass flux. The Apollo 4 peak-heating case (10.24 km/s) is also studied. For ablation rates up to 3.4% of the freestream mass flux, the radiative heating is reduced by up to 19%, whereas the convective heating is reduced by up to 87%. Good agreement with the Apollo 4 radiometer data is obtained by considering absorption in the radiometer cavity. For both the Marsreturn and the Apollo 4 cases, coupled radiation alone is found to reduce the radiative heating by 30-60% and the convective heating by less than 5%.
C1 [Johnston, Christopher O.; Gnoffo, Peter A.] NASA, Langley Res Ctr, Hampton, VA 23681 USA.
[Sutton, Kenneth] Natl Inst Aerosp, Hampton, VA 24060 USA.
RP Johnston, CO (reprint author), NASA, Langley Res Ctr, Hampton, VA 23681 USA.
NR 83
TC 18
Z9 18
U1 0
U2 1
PU AMER INST AERONAUT ASTRONAUT
PI RESTON
PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA
SN 0022-4650
J9 J SPACECRAFT ROCKETS
JI J. Spacecr. Rockets
PD MAY-JUN
PY 2009
VL 46
IS 3
BP 481
EP 491
DI 10.2514/1.40290
PG 11
WC Engineering, Aerospace
SC Engineering
GA 456ZX
UT WOS:000266895100001
ER
PT J
AU Everhart, JL
AF Everhart, Joel L.
TI Supersonic/Hypersonic Laminar Heating Correlations for Rectangular and
Impact-Induced Open and Closed Cavities
SO JOURNAL OF SPACECRAFT AND ROCKETS
LA English
DT Article; Proceedings Paper
CT 46th AIAA Aerospace Sciences Meeting and Exhibit
CY JAN 07-11, 2008
CL Reno, NV
SP AIAA
ID SEPARATED FLOWS
AB An analysis of existing baseline, zero-pressure-gradient, idealized, rectangular-geometry cavity-heating data is presented, yielding new laminar correlations for the floor-averaged heating, peak cavity endwall heating, and downstream decay rate. Correlation parameters are derived in terms of cavity geometry and local flow conditions. Prediction-limit uncertainty values are provided at the 95, 99, and 99.9% levels of significance. Nonbaseline conditions, including nonrectangular geometries and flows with known pressure gradients, are used to assess the range of applicability of the new correlations. All data variations fall within the 99% prediction-limit uncertainty bounds. Both open-flow and closed-flow cavity heating are combined into a single-curve parameterization of the heating predictions and provide a concise mathematical model of the laminar heating flowfield of stream-aligned cavities with known uncertainty.
C1 NASA, Langley Res Ctr, Aerothermodynam Branch, Hampton, VA 23681 USA.
RP Everhart, JL (reprint author), NASA, Langley Res Ctr, Aerothermodynam Branch, Hampton, VA 23681 USA.
NR 44
TC 4
Z9 4
U1 0
U2 0
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 MAY-JUN
PY 2009
VL 46
IS 3
BP 545
EP 560
DI 10.2514/1.36830
PG 16
WC Engineering, Aerospace
SC Engineering
GA 456ZX
UT WOS:000266895100006
ER
PT J
AU Mazarico, E
Zuber, MT
Lemoine, FG
Smith, DE
AF Mazarico, Erwan
Zuber, Maria T.
Lemoine, Frank G.
Smith, David E.
TI Effects of Self-Shadowing on Nonconservative Force Modeling for
Mars-Orbiting Spacecraft
SO JOURNAL OF SPACECRAFT AND ROCKETS
LA English
DT Article; Proceedings Paper
CT AIAA/AAS Astrodynamics Specialist and Exhibit
CY AUG 18-21, 2008
CL Honolulu, HI
SP AIAA, AAS
ID GRAVITY-FIELD
AB Modeling improvements of nonconservative forces affecting Mars-orbiting spacecraft are presented in this study. Recent high-resolution gravity fields enable the recovery of smaller signals in the radio tracking data, previously obscured by mismodeled gravitational anomalies. In particular, the estimation of the atmospheric drag experienced by the spacecraft benefits from the new force models. More precise calculations of the spacecraft cross-sectional areas entering the equations for the atmospheric drag and direct solar radiation pressure are possible by accounting for the interplate self-shadowing of the spacecraft physical model. The relevant surface areas can change by as much as 20% on average, and the effects can be very variable within one orbit (10%). The benefits of these updated models are assessed with two spacecraft, the Mars Odyssey and the Mars Reconnaissance Orbiter. The changes in the nonconservative forces can significantly impact the reconstructed spacecraft trajectory and the estimated model parameters depend on the spacecraft geometry and orbit. The atmospheric density estimated by the Mars Odyssey is much improved with self-shadowing applied to the solar radiation, but improvements to both the drag force and the solar radiation are important in this case of the Mars Reconnaissance Orbiter.
C1 [Mazarico, Erwan; Zuber, Maria T.] MIT, Cambridge, MA 02139 USA.
[Lemoine, Frank G.; Smith, David E.] NASA, Goddard Space Flight Ctr, Solar Syst Explorat Div, Greenbelt, MD 20771 USA.
RP Mazarico, E (reprint author), MIT, 77 Massachusetts Ave, Cambridge, MA 02139 USA.
RI Lemoine, Frank/D-1215-2013; Mazarico, Erwan/N-6034-2014
OI Mazarico, Erwan/0000-0003-3456-427X
NR 19
TC 15
Z9 15
U1 0
U2 1
PU AMER INST AERONAUT ASTRONAUT
PI RESTON
PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA
SN 0022-4650
J9 J SPACECRAFT ROCKETS
JI J. Spacecr. Rockets
PD MAY-JUN
PY 2009
VL 46
IS 3
BP 662
EP 669
DI 10.2514/1.41679
PG 8
WC Engineering, Aerospace
SC Engineering
GA 456ZX
UT WOS:000266895100017
ER
PT J
AU Squire, TH
Milos, FS
Hartlieb, GC
AF Squire, T. H.
Milos, F. S.
Hartlieb, G. C.
TI Aerospace Materials Property Database (TPSX)
SO JOURNAL OF SPACECRAFT AND ROCKETS
LA English
DT Article
C1 [Squire, T. H.; Milos, F. S.] NASA, Ames Res Ctr, Thermal Protect Mat & Syst Branch, Moffett Field, CA 94035 USA.
[Hartlieb, G. C.] ELORET Corp, Thermal Protect Mat & Syst Branch, Sunnyvale, CA 94086 USA.
RP Squire, TH (reprint author), NASA, Ames Res Ctr, Thermal Protect Mat & Syst Branch, Mail Stop 234-1, Moffett Field, CA 94035 USA.
NR 15
TC 5
Z9 5
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 MAY-JUN
PY 2009
VL 46
IS 3
BP 733
EP 736
DI 10.2514/1.43777
PG 4
WC Engineering, Aerospace
SC Engineering
GA 456ZX
UT WOS:000266895100028
ER
PT J
AU De Witt, JK
Lee, SMC
Wilson, CA
Hagan, RD
AF De Witt, John K.
Lee, Stuart M. C.
Wilson, Cassie A.
Hagan, R. Donald
TI DETERMINANTS OF TIME TO FATIGUE DURING NONMOTORIZED TREADMILL EXERCISE
SO JOURNAL OF STRENGTH AND CONDITIONING RESEARCH
LA English
DT Article
ID NEGATIVE-PRESSURE EXERCISE; UPRIGHT EXERCISE; BED REST
AB De Witt, JK, Lee, SMC, Wilson, CA, and Hagan, RD. Determinants of time to fatigue during nonmotorized treadmill exercise. J Strength Cond Res 23(3): 883-890, 2009-Treadmill exercise is commonly used for aerobic and anaerobic conditioning. During nonmotorized treadmill exercise, the subject must provide the power necessary to drive the treadmill belt. The purpose of this study was to determine what factors affected the time to fatigue on a pair of nonmotorized treadmills. Twenty subjects (10 men/10 women) attempted to complete 5 minutes of locomotion during separate trials at 3.22, 4.83, 6.44, 8.05, 9.66, and 11.27 km.h(-1). Total exercise time (<= 5 minutes) was recorded. Exercise time was converted to the number of 15-second intervals completed. Peak oxygen uptake ((V) over dotO(2)) was measured using a graded exercise test on a standard treadmill, and anthropometric measures were collected from each subject before their entrance into the study. A Cox proportional hazards regression model was used to determine significant predictive factors in a multivariate analysis. Treadmill speed and absolute peak (V) over dotO(2) were found to be significant predictors of exercise time, but there was no effect of anthropometric characteristics. Gender was found to be a predictor of treadmill time, but this was likely attributable to a higher peak (V) over dotO(2) in men than in women. The results were not affected by the type of treadmill tested in this study. Coaches and therapists should consider the cardiovascular fitness of an athlete or client when prescribing target speed because these factors are related to the total exercise time that can be achieved on a nonmotorized treadmill.
C1 [De Witt, John K.; Lee, Stuart M. C.] Wyles Life Sci Grp, Houston, TX USA.
[Wilson, Cassie A.] JES Tech, Houston, TX USA.
[Hagan, R. Donald] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA.
RP De Witt, JK (reprint author), Wyles Life Sci Grp, Houston, TX USA.
EM john.k.dewitt@nasa.gov
NR 16
TC 1
Z9 1
U1 0
U2 1
PU LIPPINCOTT WILLIAMS & WILKINS
PI PHILADELPHIA
PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA
SN 1064-8011
J9 J STRENGTH COND RES
JI J. Strength Cond. Res.
PD MAY
PY 2009
VL 23
IS 3
BP 883
EP 890
DI 10.1519/JSC.0b013e3181a04de9
PG 8
WC Sport Sciences
SC Sport Sciences
GA 514NF
UT WOS:000271400900025
PM 19387389
ER
PT J
AU Dong, W
Yen, SP
Paik, JA
Sakamoto, J
AF Dong, Winny
Yen, Shiao-Pin
Paik, Jong-Ah
Sakamoto, Jeff
TI The Role of Acetic Acid and Glycerol in the Synthesis of Amorphous MgO
Aerogels
SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY
LA English
DT Article
ID METAL-OXIDE PARTICLES; SOL-GEL TECHNIQUE; MAGNESIUM-OXIDE;
NANOCRYSTALLINE MGO; THIN-FILMS; THERMAL-DECOMPOSITION; CHEMICAL
REAGENTS; PARTIAL OXIDATION; CATALYSTS; SURFACE
AB Although sol-gel-derived magnesium-oxide (MgO) aerogels have a wide variety of applications, mostly thin films and powders of brucite, i.e. Mg(OH)(2) aerogels, have been reported. Typically, the brucite structure is converted to the periclase form of MgO upon heat-treatment. We report the role of acetic acid (HAc) and glycerol in the synthesis of amorphous MgO aerogel monoliths through the alkoxide sol-gel method. The two ligands work in concert to retard the nucleophilic substitution with water and decrease the rate of gelation, allowing for Mg-O bond formation while reducing the number of hydroxyl bonds. The amorphous material crystallizes to the periclase (MgO) phase at 400 degrees C without going through the brucite transition, resulting in a novel amorphous MgO aerogel. Specifically, we discuss the modi. cation of the Pechini process to an Mg-alkoxide sol-gel process. The roles of the ligands are investigated in the MgO gelation process through Fourier transform infrared spectroscopy, X-ray diffractometry, and thermogravimetric analysis/DSC. The physical properties of the aerogels are also reported.
C1 [Dong, Winny] Calif State Polytech Univ Pomona, Pomona, CA 91768 USA.
[Yen, Shiao-Pin; Paik, Jong-Ah] CALTECH, Jet Prop Lab, Power & Sensor Technol Sect, Pasadena, CA USA.
[Sakamoto, Jeff] Michigan State Univ, E Lansing, MI 48824 USA.
RP Dong, W (reprint author), Calif State Polytech Univ Pomona, Pomona, CA 91768 USA.
EM winnydong@csupomona.edu
FU NASA through the Jupiter Icy Moons Orbiter [NAS7-03001]
FX This work is supported by NASA through the Jupiter Icy Moons Orbiter
Project (NAS7-03001).
NR 51
TC 5
Z9 5
U1 0
U2 23
PU WILEY-BLACKWELL PUBLISHING, INC
PI MALDEN
PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA
SN 0002-7820
J9 J AM CERAM SOC
JI J. Am. Ceram. Soc.
PD MAY
PY 2009
VL 92
IS 5
BP 1011
EP 1016
DI 10.1111/j.1551-2916.2009.02997.x
PG 6
WC Materials Science, Ceramics
SC Materials Science
GA 444WT
UT WOS:000266012300007
ER
PT J
AU Springman, KR
Short, J
Rice, SD
AF Springman, K. R.
Short, J.
Rice, S. D.
TI Comments on the misuse of SPMDs in recent articles by Springman et al.
(2008a,b) and Short et al. (2008) Response
SO MARINE ENVIRONMENTAL RESEARCH
LA English
DT Letter
ID PRINCE-WILLIAM-SOUND; EXXON-VALDEZ OIL; SEMIPERMEABLE-MEMBRANE DEVICES;
SITE-SPECIFIC CONTAMINANTS; HYDROCARBON SOURCES; ALASKA; INDUCTION;
SPILL; FISH; CYTOCHROME-P4501A
C1 [Springman, K. R.] Univ Calif Davis, Littleriver, CA 95456 USA.
[Short, J.; Rice, S. D.] NOAA, Alaska Fisheries Sci Ctr, Natl Marine Fisheries Serv, Juneau, AK 99801 USA.
RP Springman, KR (reprint author), Univ Calif Davis, POB 315, Littleriver, CA 95456 USA.
EM krspringman@gmail.com
NR 21
TC 1
Z9 1
U1 1
U2 3
PU ELSEVIER SCI LTD
PI OXFORD
PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND
SN 0141-1136
J9 MAR ENVIRON RES
JI Mar. Environ. Res.
PD MAY-JUN
PY 2009
VL 67
IS 4-5
BP 259
EP 261
DI 10.1016/j.marenvres.2009.03.004
PG 3
WC Environmental Sciences; Marine & Freshwater Biology; Toxicology
SC Environmental Sciences & Ecology; Marine & Freshwater Biology;
Toxicology
GA 457DA
UT WOS:000266904800011
ER
PT J
AU van Breukelen, C
Simpson, C
Rawlings, S
Akiyama, M
Bonfield, D
Clewley, L
Jarvis, MJ
Mauch, T
Readhead, T
Stobbart, AM
Swinbank, M
Watson, M
AF van Breukelen, Caroline
Simpson, Chris
Rawlings, Steve
Akiyama, Masayuki
Bonfield, David
Clewley, Lee
Jarvis, Matt J.
Mauch, Tom
Readhead, Tony
Stobbart, Ann-Marie
Swinbank, Mark
Watson, Mike
TI Evidence of a link between the evolution of clusters and their AGN
fraction
SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
LA English
DT Article
DE galaxies: active; galaxies: clusters: general; radio continuum:
galaxies; X-rays: galaxies; X-rays: galaxies: clusters
ID ACTIVE GALACTIC NUCLEI; DEEP FIELD-SOUTH; X-RAY SOURCES; LUMINOSITY
FUNCTIONS; RADIO GALAXIES; REDSHIFT SURVEY; SKY SURVEY; CHANDRA;
SUBMILLIMETER; ENVIRONMENTS
AB We discuss the optical properties, X-ray detections and active galactic nucleus (AGN) populations of four clusters at z similar to 1 in the Subaru-XMM Deep Field (SXDF). The velocity distribution and plausible extended X-ray detections are examined, as well as the number of X-ray point sources and radio sources associated with the clusters. We find that the two clusters that appear virialized and have an extended X-ray detection contain few, if any, AGN, whereas the two pre-virialized clusters have a large AGN population. This constitutes evidence that the AGN fraction in clusters is linked to the clusters' evolutionary stage. The number of X-ray AGN in the pre-virialized clusters is consistent with an overdensity of a factor of similar to 200; the radio AGN appear to be clustered with a factor of 3 to 6 higher. The median K-band luminosities of L(K) = 1.7 +/- 0.7 L* for the X-ray sources and L(K) = 2.3 +/- 0.1 L* for the radio sources support the theory that these AGN are triggered by galaxy interaction and merging events in sub-groups with low internal velocity distributions, which make up the cluster environment in a pre-virialization evolutionary stage.
C1 [van Breukelen, Caroline] UCL, London WC1E 6BT, England.
[van Breukelen, Caroline; Rawlings, Steve; Clewley, Lee; Mauch, Tom] Univ Oxford, Dept Phys, Oxford OX1 3RH, England.
[Simpson, Chris] Liverpool John Moores Univ, Astrophys Res Inst, Birkenhead CH41 1LD, Merseyside, England.
[Akiyama, Masayuki] Natl Inst Nat Sci, Natl Astron Observ Japan, Subaru Telescope, Hilo, HI 96720 USA.
[Bonfield, David] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
[Jarvis, Matt J.] Univ Hertfordshire, Ctr Astrophys, Sci & Technol Res Inst, Hatfield AL10 9AB, Herts, England.
[Readhead, Tony] CALTECH, Owens Valley Radio Observ, Pasadena, CA 91125 USA.
[Stobbart, Ann-Marie; Watson, Mike] Univ Leicester, Dept Phys & Astron, Xray Astron Grp, Leicester LE1 7RH, Leics, England.
[Swinbank, Mark] Univ Durham, Dept Phys, Inst Computat Cosmol, Durham DH1 3LE, England.
RP van Breukelen, C (reprint author), UCL, Gower St, London WC1E 6BT, England.
EM cvb@star.ucl.ac.uk
FU STFC; W. M. Keck Foundation
FX The authors would like to thank Doi, Morokuma, Miyazaki, Saito, Yamada,
Satoshi, Smail and Croom for sharing their redshifts in the SXDF master
list. CVB acknowledges support from STFC in the form of a postdoctoral
fellowship. This paper is partly based on observations obtained at the
Gemini Observatory, which is operated by the Association of Universities
for Research in Astronomy, Inc., under a cooperative agreement with the
NSF on behalf of the Gemini partnership: the National Science Foundation
(United States), the Science and Technology Facilities Council (United
Kingdom), the National Research Council (Canada), CONICYT (Chile), the
Australian Research Council (Australia), Ministrio da Cincia e
Tecnologia (Brazil) and SECYT (Argentina). Some of the data presented
herein were obtained at the W. M. Keck Observatory, which is operated as
a scientific partnership among the California Institute of Technology,
the University of California and the National Aeronautics and Space
Administration. The Observatory was made possible by the generous
financial support of the W. M. Keck Foundation. The authors wish to
recognize and acknowledge the very significant cultural role and
reverence that the summit of Mauna Kea has always had within the
indigenous Hawaiian community. We are most fortunate to have the
opportunity to conduct observations from this mountain.
NR 59
TC 11
Z9 11
U1 0
U2 1
PU WILEY-BLACKWELL PUBLISHING, INC
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 MAY 1
PY 2009
VL 395
IS 1
BP 11
EP 27
DI 10.1111/j.1365-2966.2009.14513.x
PG 17
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 431QS
UT WOS:000265078700022
ER
PT J
AU Page, KL
Willingale, R
O'Brien, PT
Tanvir, NR
Osborne, JP
Zhang, B
Holland, ST
Levan, AJ
Melandri, A
Starling, RLC
Bersier, D
Burrows, DN
Geach, JE
Maxted, P
AF Page, K. L.
Willingale, R.
O'Brien, P. T.
Tanvir, N. R.
Osborne, J. P.
Zhang, B.
Holland, S. T.
Levan, A. J.
Melandri, A.
Starling, R. L. C.
Bersier, D.
Burrows, D. N.
Geach, J. E.
Maxted, P.
TI The unusual X-ray light curve of GRB 080307: the onset of the afterglow?
SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
LA English
DT Article
DE radiation mechanisms: non-thermal; gamma-rays: bursts; X-rays:
individual: GRB 080307
ID SWIFT XRT DATA; BURST AFTERGLOW; ENGINE ACTIVITY; 1ST SURVEY; TELESCOPE;
BRIGHT; SUPERNOVA; EVOLUTION; EMISSION; FLARES
AB Swift-detected GRB080307 showed an unusual smooth rise in its X-ray light curve around 100 s after the burst, at the start of which the emission briefly softened. This 'hump' has a longer duration than is normal for a flare at early times and does not demonstrate a typical flare profile. Using a two-component power-law-to-exponential model, the rising emission can be modelled as the onset of the afterglow, something which is very rarely seen in Swift-X-ray light curves. We cannot, however, rule out that the hump is a particularly slow early-time flare, or that it is caused by upscattered reverse shock electrons.
C1 [Page, K. L.; Willingale, R.; O'Brien, P. T.; Tanvir, N. R.; Osborne, J. P.; Starling, R. L. C.] Univ Leicester, Xray & Observat Astron Grp, Dept Phys & Astron, Leicester LE1 7RH, Leics, England.
[Zhang, B.] Univ Nevada, Dept Phys, Las Vegas, NV 89154 USA.
[Holland, S. T.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
[Holland, S. T.] Univ Space Res Assoc, Columbia, MD 21044 USA.
[Levan, A. J.] Univ Warwick, Dept Phys, Coventry CV4 7AL, W Midlands, England.
[Melandri, A.; Bersier, D.] Liverpool John Moores Univ, Astrophys Res Inst, Birkenhead CH41 1LD, Merseyside, England.
[Burrows, D. N.] Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA.
[Geach, J. E.] Univ Durham, Dept Phys, Durham DH1 3LE, England.
[Maxted, P.] Univ Keele, Astrophys Grp, Keele ST5 5BG, Staffs, England.
RP Page, KL (reprint author), Univ Leicester, Xray & Observat Astron Grp, Dept Phys & Astron, Leicester LE1 7RH, Leics, England.
EM kpa@star.le.ac.uk
NR 72
TC 5
Z9 5
U1 0
U2 1
PU WILEY-BLACKWELL PUBLISHING, INC
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 MAY 1
PY 2009
VL 395
IS 1
BP 328
EP 334
DI 10.1111/j.1365-2966.2009.14509.x
PG 7
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 431QS
UT WOS:000265078700045
ER
PT J
AU Oates, SR
Page, MJ
Schady, P
de Pasquale, M
Koch, TS
Breeveld, AA
Brown, PJ
Chester, MM
Holland, ST
Hoversten, EA
Kuin, NPM
Marshall, FE
Roming, PWA
Still, M
Berk, DEV
Zane, S
Nousek, JA
AF Oates, S. R.
Page, M. J.
Schady, P.
de Pasquale, M.
Koch, T. S.
Breeveld, A. A.
Brown, P. J.
Chester, M. M.
Holland, S. T.
Hoversten, E. A.
Kuin, N. P. M.
Marshall, F. E.
Roming, P. W. A.
Still, M.
Berk, D. E. Vanden
Zane, S.
Nousek, J. A.
TI A statistical study of gamma-ray burst afterglows measured by the Swift
Ultraviolet Optical Telescope
SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
LA English
DT Article
DE gamma-rays: bursts
ID LIGHT CURVES; 2-COMPONENT JET; LORENTZ FACTOR; REVERSE SHOCK; XRT DATA;
EMISSION; FLASHES; SPECTRA; IDENTIFICATION; LUMINOSITIES
AB We present the first statistical analysis of 27 Ultraviolet Optical Telescope (UVOT) optical/ultraviolet light curves of gamma-ray burst (GRB) afterglows. We have found, through analysis of the light curves in the observer's frame, that a significant fraction rise in the first 500 s after the GRB trigger, all light curves decay after 500 s, typically as a power law with a relatively narrow distribution of decay indices, and the brightest optical afterglows tend to decay the quickest. We find that the rise could be either produced physically by the start of the forward shock, when the jet begins to plough into the external medium, or geometrically where an off-axis observer sees a rising light curve as an increasing amount of emission enters the observers line of sight, which occurs as the jet slows. We find that at 99.8 per cent confidence, there is a correlation, in the observed frame, between the apparent magnitude of the light curves at 400 s and the rate of decay after 500 s. However, in the rest frame, a Spearman rank test shows only a weak correlation of low statistical significance between luminosity and decay rate. A correlation should be expected if the afterglows were produced by off-axis jets, suggesting that the jet is viewed from within the half-opening angle. or within a core of a uniform energy density theta(c). We also produced logarithmic luminosity distributions for three rest-frame epochs. We find no evidence for bimodality in any of the distributions. Finally, we compare our sample of UVOT light curves with the X-ray Telescope (XRT) light-curve canonical model. The range in decay indices seen in UVOT light curves at any epoch is most similar to the range in decay of the shallow decay segment of the XRT canonical model. However, in the XRT canonical model, there is no indication of the rising behaviour observed in the UVOT light curves.
C1 [Oates, S. R.; Page, M. J.; Schady, P.; de Pasquale, M.; Breeveld, A. A.; Kuin, N. P. M.; Still, M.; Zane, S.] Univ Coll London, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England.
[Koch, T. S.; Brown, P. J.; Chester, M. M.; Hoversten, E. A.; Roming, P. W. A.; Berk, D. E. Vanden; Nousek, J. A.] Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA.
[Holland, S. T.; Marshall, F. E.] NASA, Goddard Space Flight Ctr, Astrophys Sci Div, Greenbelt, MD 20771 USA.
[Holland, S. T.] Univ Space Res Assoc, Columbia, MD 21044 USA.
[Holland, S. T.] NASA, Goddard Space Flight Ctr, Ctr Res & Explorat Space Sci & Technol, Code 688 8, Greenbelt, MD 20771 USA.
RP Oates, SR (reprint author), Univ Coll London, Mullard Space Sci Lab, Holmbury St Mary, Dorking RH5 6NT, Surrey, England.
EM sro@mssl.ucl.ac.uk
FU STFC
FX This research has made use of data obtained from the High Energy
Astrophysics Science Archive Research Center (HEASARC) and the Leicester
Data base and Archive Service (LEDAS), provided by NASA's Goddard Space
Flight Center and the Department of Physics and Astronomy, Leicester
University, UK, respectively. SRO acknowledges the support of an STFC
studentship. SZ thanks STFC for its support through an STFC advanced
fellowship.
NR 77
TC 79
Z9 79
U1 0
U2 4
PU WILEY-BLACKWELL PUBLISHING, INC
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 MAY 1
PY 2009
VL 395
IS 1
BP 490
EP 503
DI 10.1111/j.1365-2966.2009.14544.x
PG 14
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 431QS
UT WOS:000265078700061
ER
PT J
AU Kuin, NPM
Landsman, W
Page, MJ
Schady, P
Still, M
Breeveld, AA
De Pasquale, M
Roming, PWA
Brown, PJ
Carter, M
James, C
Curran, PA
Cucchiara, A
Gronwall, C
Holland, ST
Hoversten, EA
Hunsberger, S
Kennedy, T
Koch, S
Lamoureux, H
Marshall, FE
Oates, SR
Parsons, A
Palmer, DM
Smith, PJ
AF Kuin, N. P. M.
Landsman, W.
Page, M. J.
Schady, P.
Still, M.
Breeveld, A. A.
De Pasquale, M.
Roming, P. W. A.
Brown, P. J.
Carter, M.
James, C.
Curran, P. A.
Cucchiara, A.
Gronwall, C.
Holland, S. T.
Hoversten, E. A.
Hunsberger, S.
Kennedy, T.
Koch, S.
Lamoureux, H.
Marshall, F. E.
Oates, S. R.
Parsons, A.
Palmer, D. M.
Smith, P. J.
TI GRB 081203A: Swift UVOT captures the earliest ultraviolet spectrum of a
gamma-ray burst
SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
LA English
DT Article
DE instrumentation: spectrographs; gamma-rays: bursts
ID TELESCOPE; DUST; ABSORPTION; GAS; SPECTROSCOPY; MISSION; STAR; HI
AB We present the earliest ultraviolet (UV) spectrum of a gamma-ray burst (GRB) as observed with the Swift Ultra-Violet/Optical Telescope (UVOT). The GRB 081203A spectrum was observed for 50 s with the UV-grism starting 251 s after the Swift-Burst-Alert-Telescope (BAT) trigger. During this time, the GRB was approximate to 13.4 mag (u filter) and was still rising to its peak optical brightness. In the UV-grism spectrum, we find a damped Ly alpha line, Ly beta and the Lyman continuum break at a redshift z = 2.05 +/- 0.01. A model fit to the Lyman absorption implies a gas column density of log N(HI) = 22.0 +/- 0.1 cm(-2), which is typical of GRB host galaxies with damped Ly alpha absorbers. This observation of GRB 081203A demonstrates that for brighter GRBs (v approximate to 14 mag) with moderate redshift (0.5 < z < 3.5) the UVOT is able to provide redshifts, and probe for damped Ly alpha absorbers within 4-6 min from the time of the Swift-BAT trigger.
C1 [Kuin, N. P. M.; Page, M. J.; Schady, P.; Still, M.; Breeveld, A. A.; De Pasquale, M.; Carter, M.; James, C.; Curran, P. A.; Kennedy, T.; Lamoureux, H.; Oates, S. R.; Smith, P. J.] Univ Coll London, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England.
[Landsman, W.; Holland, S. T.; Marshall, F. E.; Parsons, A.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
[Roming, P. W. A.; Brown, P. J.; Cucchiara, A.; Gronwall, C.; Hoversten, E. A.; Hunsberger, S.; Koch, S.] Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA.
[Palmer, D. M.] Los Alamos Natl Lab, Los Alamos, NM 87545 USA.
RP Kuin, NPM (reprint author), Univ Coll London, Mullard Space Sci Lab, Holmbury St Mary, Dorking RH5 6NT, Surrey, England.
EM npmk@mssl.ucl.ac.uk
RI Parsons, Ann/I-6604-2012; Curran, Peter/B-5293-2013
OI Curran, Peter/0000-0003-3003-4626
FU UK Science and Technology Facilities Council; NASA [NAS5-00136]
FX This work was supported by the UK Science and Technology Facilities
Council through a grant for Swift Post Launch Support at UCL-MSSL. This
work is sponsored at PSU by NASA contract NAS5-00136. We acknowledge
useful comments by the anonymous referee which led to improvement of the
grism analysis. We would like to dedicate this Letter to the late
Richard Bingham, whose visionary optical design for the UVOT grism made
these observations possible.
NR 27
TC 22
Z9 22
U1 0
U2 1
PU WILEY-BLACKWELL PUBLISHING, INC
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 MAY 1
PY 2009
VL 395
IS 1
BP L21
EP L24
DI 10.1111/j.1745-3933.2009.00632.x
PG 4
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 431QS
UT WOS:000265078700005
ER
PT J
AU Daescu, DN
Todling, R
AF Daescu, Dacian N.
Todling, Ricardo
TI Adjoint Estimation of the Variation in Model Functional Output due to
the Assimilation of Data
SO MONTHLY WEATHER REVIEW
LA English
DT Article
ID OBSERVATION IMPACT; OBSERVATION SENSITIVITY; ANALYSIS SYSTEM;
IMPLEMENTATION; APPROXIMATIONS; ATLANTIC; 4D-VAR
AB A parametric approach to the adjoint estimation of the variation in model functional output due to the assimilation of data is considered as a tool to analyze and develop observation impact measures. The parametric approach is specialized to a linear analysis scheme and it is used to derive various high-order approximation equations. This framework includes the Kalman filter and incremental three-a nd four-dimensional variational data assimilation schemes implementing a single outer loop iteration. Distinction is made between Taylor series methods and numerical quadrature methods. The novel quadrature approximations require minimal additional software development and are suitable for testing and implementation at operational numerical weather prediction centers where a data assimilation system (DAS) and the associated adjoint DAS are in place. Their potential use as tools for observation impact estimates needs to be further investigated. Preliminary numerical experiments are provided using the fifth-generation NASA Goddard Earth Observing System (GEOS-5) atmospheric DAS.
C1 [Daescu, Dacian N.] Portland State Univ, Dept Math & Stat, Portland, OR 97207 USA.
[Todling, Ricardo] NASA GSFC, Global Modeling & Assimilat Off, Greenbelt, MD 20771 USA.
RP Daescu, DN (reprint author), Portland State Univ, Dept Math & Stat, POB 751, Portland, OR 97207 USA.
EM daescu@pdx.edu
RI Daescu, Dacian /B-3457-2010
FU Atmospheric Data Assimilation Development component of the NASA
Modeling, Analysis, and Prediction Program [MAP/04-0000-0080]; NASA
Modeling, Analysis, and Prediction Program [NNG06GC67G]
FX The numerical results in this work were obtained on the Linux Explore
System through a cooperation with the NASA Center for Computational
Sciences at Goddard Space Flight Center. The work of D. N. Daescu was
supported by the NASA Modeling, Analysis, and Prediction Program under
Award NNG06GC67G. The work of R. Todling was partially supported by the
Atmospheric Data Assimilation Development component of the NASA
Modeling, Analysis, and Prediction Program (MAP/04-0000-0080). We thank
two anonymous reviewers whose thoughtful comments and suggestions helped
to improve themanuscript.
NR 36
TC 18
Z9 18
U1 0
U2 3
PU AMER METEOROLOGICAL SOC
PI BOSTON
PA 45 BEACON ST, BOSTON, MA 02108-3693 USA
SN 0027-0644
J9 MON WEATHER REV
JI Mon. Weather Rev.
PD MAY
PY 2009
VL 137
IS 5
BP 1705
EP 1716
DI 10.1175/2008MWR2659.1
PG 12
WC Meteorology & Atmospheric Sciences
SC Meteorology & Atmospheric Sciences
GA 451UC
UT WOS:000266495000014
ER
PT J
AU Sola, F
Biaggi-Labiosa, A
Fonseca, LF
Resto, O
Lebron-Colon, M
Meador, MA
AF Sola, F.
Biaggi-Labiosa, A.
Fonseca, L. F.
Resto, O.
Lebron-Colon, M.
Meador, M. A.
TI Field Emission and Radial Distribution Function Studies of Fractal-like
Amorphous Carbon Nanotips
SO NANOSCALE RESEARCH LETTERS
LA English
DT Article
DE Carbon nanotips; Graphite-like a-C; EELS; EFED; Field emission
ID THIN-FILMS; ASPECT-RATIO; GROWTH; FABRICATION; NANOWIRES; NANOTUBES;
SILICON; ARRAYS
AB The short-range order of individual fractal-like amorphous carbon nanotips was investigated by means of energy-filtered electron diffraction in a transmission electron microscope (TEM). The nanostructures were grown in porous silicon substrates in situ within the TEM by the electron beam-induced deposition method. The structure factor S(k) and the reduced radial distribution function G(r) were calculated. From these calculations a bond angle of 124A degrees was obtained which suggests a distorted graphitic structure. Field emission was obtained from individual nanostructures using two micromanipulators with sub-nanometer positioning resolution. A theoretical three-stage model that accounts for the geometry of the nanostructures provides a value for the field enhancement factor close to the one obtained experimentally from the Fowler-Nordheim law.
C1 [Sola, F.; Biaggi-Labiosa, A.; Fonseca, L. F.; Resto, O.] Univ Puerto Rico, Inst Funct Nanomat, Dept Phys, San Juan, PR 00931 USA.
[Lebron-Colon, M.; Meador, M. A.] NASA, Glenn Res Ctr, Polymer Mat Branch, Mat & Struct Div, Cleveland, OH 44135 USA.
RP Fonseca, LF (reprint author), Univ Puerto Rico, Inst Funct Nanomat, Dept Phys, POB 23343, San Juan, PR 00931 USA.
EM luis.upr@gmail.com
FU NASA [NNX08BA48A, NNG05GG78H]; NSF [0701525]; U. S. Department of Energy
[DE-AC02-05CH11231]
FX This study was supported by the following grants numbers and projects:
NASA NNX08BA48A, NASA Space Grant NNG05GG78H, NSF 0701525, Fundamental
Aeronautics Program and Subsonic Fixed Wing Project. The authors
acknowledge the National Center for Electron Microscopy, Lawrence
Berkeley Lab, which is supported by the U. S. Department of Energy under
Contract # DE-AC02-05CH11231,and in particular to Dr. A. Minor for
helping us with the FE experimental setup. F.S. kindly acknowledges Dr.
D. J. H. Cockayne from Oxford University and D. Hull from NASA GRC for
providing helpful information related to the electron diffraction
analysis.
NR 30
TC 9
Z9 11
U1 1
U2 10
PU SPRINGER
PI NEW YORK
PA 233 SPRING ST, NEW YORK, NY 10013 USA
SN 1556-276X
J9 NANOSCALE RES LETT
JI Nanoscale Res. Lett.
PD MAY
PY 2009
VL 4
IS 5
BP 431
EP 436
DI 10.1007/s11671-009-9270-5
PG 6
WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary;
Physics, Applied
SC Science & Technology - Other Topics; Materials Science; Physics
GA 423HQ
UT WOS:000264487800006
ER
PT J
AU Svanda, M
Klvana, M
Sobotka, M
Kosovichev, AG
Duvall, TL
AF Svanda, M.
Klvana, M.
Sobotka, M.
Kosovichev, A. G.
Duvall, T. L., Jr.
TI Large-scale horizontal flows in the solar photosphere IV. On the
vertical structure of large-scale horizontal flows
SO NEW ASTRONOMY
LA English
DT Article
DE The Sun: photosphere; Sun: interior; Sun: helioseismology
ID TIME-DISTANCE HELIOSEISMOLOGY; RAY APPROXIMATIONS; ACTIVE-REGION;
SUPERGRANULATION; SUN; SUPERROTATION; OSCILLATION; TOMOGRAPHY; ACCURACY;
ROTATION
AB In the recent papers, we introduced a method utilised to measure the flow field. The method is based on the tracking of supergranular structures. We did not precisely know, whether its results represent the flow field in the photosphere or in some subphotospheric layers. In this paper, in combination with helioseismic data, we are able to estimate the depths in the solar convection envelope, where the detected large-scale flow field is well represented by the surface measurements. We got a clear answer to question what kind of structures we track in full-disc Dopplergrams. It seems that in the quiet Sun regions the supergranular structures are tracked, while in the regions with the magnetic field the structures of the magnetic field are dominant. This observation seems obvious, because the nature of Doppler Structures is different in the magnetic regions and in the quiet Sun. We show that the large-scale flow detected by our method represents the motion of plasma in layers down to similar to 10 Mm. The supergranules may therefore be treated as the objects carried by the underlying large-scale velocity field. (C) 2008 Elsevier B.V. All rights reserved.
C1 [Svanda, M.] Charles Univ Prague, Astron Inst, Fac Math & Phys, CZ-18000 Prague 8, Czech Republic.
[Svanda, M.; Klvana, M.; Sobotka, M.] Acad Sci Czech Republic, Astron Inst, CZ-25165 Ondrejov, Czech Republic.
[Kosovichev, A. G.] Stanford Univ, WW Hansen Expt Phys Lab, Stanford, CA 94305 USA.
[Duvall, T. L., Jr.] NASA, Goddard Space Flight Ctr, Solar Phys Lab, Greenbelt, MD 20771 USA.
RP Svanda, M (reprint author), Charles Univ Prague, Astron Inst, Fac Math & Phys, V Holesovickach 2, CZ-18000 Prague 8, Czech Republic.
EM michal@astronomie.cz; mklvana@asu.cas.cz; msobotka@asu.cas.cz;
sasha@quake.stanford.edu; thomas.l.duvall@nasa.gov
RI Svanda, Michal/A-6576-2008; Duvall, Thomas/C-9998-2012; Sobotka,
Michal/G-9042-2014; Klvana, Miroslav/G-9026-2014
OI Svanda, Michal/0000-0002-6345-1007; Sobotka, Michal/0000-0001-5439-7822;
FU Academy of Sciences of the Czech Republic [IAA30030808]; ESA-PECS
[98030]; Astronomical Institute of ASCR [AV0Z10030501]; Astronomical
Institute of Charles University [MSM0021620860]
FX M.S., M.K., and M.S. were supported by the Grant Agency of Academy of
Sciences of the Czech Republic under grant IAA30030808, M.. additionally
by ESA-PECS under grant No. 98030. The Astronomical Institute of ASCR is
working on the Research project AV0Z10030501 (Academy of Sciences of
CR), the Astronomical Institute of Charles University on the Research
program MSM0021620860 (Ministry of Education of CR). SOHO is a project
of international cooperation between ESA and NASA.
NR 29
TC 7
Z9 7
U1 0
U2 0
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 1384-1076
J9 NEW ASTRON
JI New Astron.
PD MAY
PY 2009
VL 14
IS 4
BP 429
EP 434
DI 10.1016/j.newast.2008.12.003
PG 6
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 409TH
UT WOS:000263528200011
ER
PT J
AU Barnes, NP
Walsh, BM
Reichle, DJ
DeYoung, RJ
AF Barnes, Norman P.
Walsh, Brian M.
Reichle, Donald J.
DeYoung, Russell J.
TI Tm:fiber lasers for remote sensing
SO OPTICAL MATERIALS
LA English
DT Article; Proceedings Paper
CT 3rd International Workshop on Photonic and Electronic Materials
CY JUL 04-06, 2007
CL San Sebastian, SPAIN
SP Donostia Int Phys Ctr
AB Tm:fiber lasers are an attractive choice for remote sensing of water under and conditions, such as found on Mars. Renewed interest in Martian exploration and discovery Of huge deposits of water at the Martian south pole fuel interest in a water vapor lidar. The potential for high efficiency and the robust and compact nature of fiber lasers are very attractive features. Laser diodes, suitable for pumping Tm:fiber lasers, operate around 0.8 mu m. Tm:fiber lasers operate around 1.9 mu m, in a strong water vapor absorption region. For the laser to be highly efficient, Tm: fiber lasers must operate with a quantum efficiency of two. That is, two laser photons are produced for one absorbed pump photon. The role the fiber material plays and the dynamics of the Tin self quenching process must be understood to optimize this device. Both the physics and experimental results will be presented. Published by Elsevier B.V.
C1 [Barnes, Norman P.; Walsh, Brian M.; Reichle, Donald J.; DeYoung, Russell J.] NASA, Langley Res Ctr, Hampton, VA 23681 USA.
RP Barnes, NP (reprint author), NASA, Langley Res Ctr, Hampton, VA 23681 USA.
EM norman.p.barnes@nasa.gov
NR 1
TC 16
Z9 17
U1 4
U2 9
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0925-3467
J9 OPT MATER
JI Opt. Mater.
PD MAY
PY 2009
VL 31
IS 7
BP 1061
EP 1064
DI 10.1016/j.optmat.2007.11.037
PG 4
WC Materials Science, Multidisciplinary; Optics
SC Materials Science; Optics
GA 449WH
UT WOS:000266360600005
ER
PT J
AU Kwoun, OI
Lu, Z
AF Kwoun, Oh-ig
Lu, Zhong
TI Multi-temporal RADARSAT-1 and ERS Backscattering Signatures of Coastal
Wetlands in Southeastern Louisiana
SO PHOTOGRAMMETRIC ENGINEERING AND REMOTE SENSING
LA English
DT Article
ID SYNTHETIC-APERTURE RADAR; AMAZON FLOODPLAIN; UNITED-STATES; SAR DATA;
VEGETATION; IMAGERY; INTERFEROMETRY; JERS-1; AREA
AB Using multi-temporal European Remote-sensing Satellites (ERS-1/-2) and Canadian Rodar Satellite (RADARSAT-1) synthetic aperture radar (SAR) data over the Louisiana coastal zone, we characterize seasonal variations of radar backscattering according to vegetation type. Our main findings are as follows. First, ERS-1/-2 and HADARSAT-1 require careful radiometric calibration to perform multi-temporal backscattering analysis for wetland mapping. We use SAR backscattering signals from cities for the relative calibration. Second, using seasonally averaged backscattering coefficients from ERS-1/-2 and RADARSAT-1, we can differentiate most forests (bottomland and swamp forests) and marshes (freshwater, intermediate, brackish, and saline marshes) in coastal wetlands. The student t-test results support the usefulness of season-averaged backscatter data for classification. Third, combining SAR backscattering coefficients and an optical-sensor-based normalized difference vegetation index can provide further insight into vegetation type and enhance the separation between forests and marshes. Our study demonstrates that SAR can provide necessary information to characterize coastal wetlands and monitor their changes.
C1 [Kwoun, Oh-ig] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
[Kwoun, Oh-ig] US Geol Survey, SAIC, EROS Data Ctr, Sioux Falls, SD 57198 USA.
[Lu, Zhong] USGS EROS Ctr, Vancouver, WA 98683 USA.
[Lu, Zhong] Cascades Volcano Observ, Vancouver, WA 98683 USA.
RP Kwoun, OI (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA.
EM kwoun@jpl.nasa.gov; lu@usgs.gov
FU U.S. Geological Survey (USCS) Director Venture Capital Fund; USGS
Eastern Region Venture Capital Fund; USGS Land Remote Sensing Program;
USGS [O3CRCN0001]
FX ERS-1/ERS-2 SAR images are copyrighted @ 1992, 1993, 1996, 1997, and
1998 by the European Space Agency (ESA) and were provided by the ESA
using the Category-1 Project 2853. RADARSAT-1 images are copyrighted (D
2002, 2003, and 2004 by the Canadian Space Agency (CSA) and were
provided. by the Alaska Satellite Facility (ASF). This research was
supported by funding from the U.S. Geological Survey (USCS) Director
Venture Capital Fund, USGS Eastern Region Venture Capital Fund, USGS
Land Remote Sensing Program, and USGS contract O3CRCN0001. We thank
Elijah Ramsey and Terry Sohl for careful reviews and constructive
comments.
NR 41
TC 8
Z9 10
U1 2
U2 10
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 MAY
PY 2009
VL 75
IS 5
BP 607
EP 617
PG 11
WC Geography, Physical; Geosciences, Multidisciplinary; Remote Sensing;
Imaging Science & Photographic Technology
SC Physical Geography; Geology; Remote Sensing; Imaging Science &
Photographic Technology
GA 446PQ
UT WOS:000266134000011
ER
PT J
AU Nielsen, KE
Gull, TR
AF Nielsen, Krister E.
Gull, Theodore R.
TI Eta Carinae: an Astrophysical Laboratory
SO PHYSICA SCRIPTA
LA English
DT Article; Proceedings Paper
CT 9th International Conference on Atomic Spectroscopy and Oscillator
Strengths for Astrophysical and Laboratory Plasma
CY AUG 07-10, 2007
CL Lund Univ, Lund Observatory & Phys Dept, Lund, SWEDEN
HO Lund Univ, Lund Observatory & Phys Dept
ID HOMUNCULUS-NEBULA; 2003.5 MINIMUM; EJECTA ABSORPTION; EMISSION-LINES; II
EMISSION; ULTRAVIOLET; SPECTRUM; VARIABILITY; DISCOVERY; COMPANION
AB Eta Carinae provides a unique example to investigate a massive star in a late evolutionary phase and how CNO-processed material is ejected and mixed with the interstellar medium. The absorbing gas surrounding Eta Carinae (eta Car) shows similar characteristics to the intervening gas in spectra of gamma ray burst progenitors. Consequently, the eta Car spectrum may provide clues about the nature of other extreme objects such as hypernovae and supernova impostors. In the 1840s, eta Car underwent a massive ejection, which was repeated to a lesser extent in the 1890s. Today we see the Homunculus, a bipolar expanding neutral shell, and the Little Homunculus, an interior, spectroscopically time-variable, ionized structure. The eta Car system is ideal as a laboratory for absorption and emission line spectroscopy. In the line-of-sight towards eta Car, multiple narrow absorption lines are observed from environments with densities around 10(7) cm(-3) and temperatures ranging from 60 to 7000 K. Thousands of neutral/singly ionized metal lines are identified, in addition to molecular lines in species such as H(2), CH, OH and NH. The input from the laboratory spectroscopy community has furthered the analysis of eta Car. Future observations of eta Car in the infrared through radio wavelength region will enable new detections of atomic and molecular transitions, most notably of hydrides and nitrides. We will demonstrate how experimentally derived atomic data have improved our spectral analysis, and illuminate where future work is needed.
C1 [Nielsen, Krister E.; Gull, Theodore R.] NASA, Goddard Space Flight Ctr, Astrophys Sci Div, Greenbelt, MD 20771 USA.
RP Nielsen, KE (reprint author), Catholic Univ Amer, Washington, DC 20064 USA.
EM krister.nielsen@nasa.gov
RI Gull, Theodore/D-2753-2012
OI Gull, Theodore/0000-0002-6851-5380
NR 28
TC 2
Z9 2
U1 0
U2 0
PU IOP PUBLISHING LTD
PI BRISTOL
PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND
SN 0031-8949
J9 PHYS SCRIPTA
JI Phys. Scr.
PD MAY
PY 2009
VL T134
AR 014002
DI 10.1088/0031-8949/2009/T134/014002
PG 9
WC Physics, Multidisciplinary
SC Physics
GA 465UG
UT WOS:000267612800003
ER
PT J
AU Drasco, S
AF Drasco, Steve
TI Verifying black hole orbits with gravitational spectroscopy
SO PHYSICAL REVIEW D
LA English
DT Article
ID MASS-RATIO INSPIRALS; KERR SPACETIME; ADIABATIC EVOLUTION; CIRCULAR
ORBIT; POINT MASSES; RADIATION; LISA; PERTURBATIONS; RELATIVITY;
PARAMETERS
AB Gravitational waves from test masses bound to geodesic orbits of rotating black holes are simulated, using Teukolsky's black hole perturbation formalism, for about ten thousand generic orbital configurations. Each binary radiates power exclusively in modes with frequencies that are integer-linear combinations of the orbit's three fundamental frequencies. General spectral properties are found with a survey of orbits about a black hole taken to be rotating at 80% of the maximal spin. The orbital eccentricity is varied from 0.1 to 0.9. Inclination ranges from 20 degrees to 160 degrees and comes to within 20 degrees of polar. Semilatus rectum is varied from 1.2 to 3 times the value at the innermost stable circular orbits. The following general spectral properties are found: (i) 99% of the radiated power is typically carried by a few hundred modes, and at most by about a thousand modes, (ii) the dominant frequencies can be grouped into a small number of families defined by fixing two of the three integer frequency multipliers, and (iii) the specifics of these trends can be qualitatively inferred from the geometry of the orbit under consideration. Detections using triperiodic analytic templates modeled on these general properties would constitute a verification of radiation from an adiabatic sequence of black hole orbits and would recover the evolution of the fundamental orbital frequencies. In an analogy with ordinary spectroscopy, this would compare to observing the Bohr model's atomic hydrogen spectrum without being able to rule out alternative atomic theories or nuclei. The suitability of such a detection technique is demonstrated using snapshots computed at 12-hour intervals throughout the last three years before merger of a kludged inspiral. The system chosen is typical of those thought to occur in galactic nuclei and to be observable with space-based gravitational wave detectors like LISA. Because of circularization, the number of excited modes decreases as the binary evolves. A hypothetical detection algorithm that tracks mode families dominating the first 12 hours of the inspiral would capture 98% of the total power over the remaining three years.
C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
RP Drasco, S (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA.
NR 64
TC 4
Z9 4
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 MAY
PY 2009
VL 79
IS 10
AR 104016
DI 10.1103/PhysRevD.79.104016
PG 18
WC Astronomy & Astrophysics; Physics, Particles & Fields
SC Astronomy & Astrophysics; Physics
GA 451WP
UT WOS:000266501900070
ER
PT J
AU Tinto, M
Dick, GJ
Prestage, JD
Armstrong, JW
AF Tinto, Massimo
Dick, George J.
Prestage, John D.
Armstrong, J. W.
TI Improved spacecraft radio science using an on-board atomic clock:
Application to gravitational wave searches
SO PHYSICAL REVIEW D
LA English
DT Article
ID DOPPLER TRACKING; RADIATION; LINKS
AB Recent advances in space-qualified atomic clocks (low-mass, low power-consumption, frequency stability comparable to that of ground-based clocks) can enable interplanetary spacecraft radio science experiments at unprecedented Doppler sensitivities. The addition of an on-board digital receiver would allow the up- and down-link Doppler frequencies to be measured separately. Such separate, high-quality measurements allow optimal data combinations that suppress the currently leading noise sources: phase scintillation noise from the Earth's atmosphere and Doppler noise caused by mechanical vibrations of the ground antenna. Here we provide a general expression for the optimal combination of ground and on-board Doppler data and compute the sensitivity such a system would have to low-frequency gravitational waves (GWs). Assuming a plasma scintillation noise calibration comparable to that already demonstrated with the multilink CASSINI radio system, the space-clock/digital-receiver instrumentation enhancements would give GW strain sensitivity of 3.7x10(-14) Hz(-1/2) for randomly polarized, monochromatic GW signals isotropically distributed over the celestial sphere, over a two-decade (similar to 0.0001-0.01 Hz) region of the low-frequency band. This is about an order of magnitude better than currently achieved with traditional two-way coherent Doppler experiments. The utility of optimally combining simultaneous up- and down-link observations is not limited to GW searches. The Doppler tracking technique discussed here could be performed at minimal incremental cost to improve also other radio science experiments (i.e., tests of relativistic gravity, planetary and satellite gravity field measurements, atmospheric and ring occultations) on future interplanetary missions.
C1 [Tinto, Massimo; Dick, George J.; Prestage, John D.; Armstrong, J. W.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
RP Tinto, M (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA.
EM Massimo.Tinto@jpl.nasa.gov; George.J.Dick@jpl.nasa.gov;
John.D.Prestage@jpl.nasa.gov; John.W.Armstrong@jpl.nasa.gov
NR 27
TC 3
Z9 3
U1 0
U2 2
PU AMER 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 MAY
PY 2009
VL 79
IS 10
AR 102003
DI 10.1103/PhysRevD.79.102003
PG 9
WC Astronomy & Astrophysics; Physics, Particles & Fields
SC Astronomy & Astrophysics; Physics
GA 451WP
UT WOS:000266501900009
ER
PT J
AU Kuranz, CC
Drake, RP
Grosskopf, MJ
Budde, A
Krauland, C
Marion, DC
Visco, AJ
Ditmar, JR
Robey, HF
Remington, BA
Miles, AR
Cooper, ABR
Sorce, C
Plewa, T
Hearn, NC
Killebrew, KL
Knauer, JP
Arnett, D
Donajkowski, T
AF Kuranz, C. C.
Drake, R. P.
Grosskopf, M. J.
Budde, A.
Krauland, C.
Marion, D. C.
Visco, A. J.
Ditmar, J. R.
Robey, H. F.
Remington, B. A.
Miles, A. R.
Cooper, A. B. R.
Sorce, C.
Plewa, T.
Hearn, N. C.
Killebrew, K. L.
Knauer, J. P.
Arnett, D.
Donajkowski, T.
TI Three-dimensional blast-wave-driven Rayleigh-Taylor instability and the
effects of long-wavelength modes
SO PHYSICS OF PLASMAS
LA English
DT Article; Proceedings Paper
CT 50th Annual Meeting of the Division of Plasma Physics of the
American-Physical-Society
CY NOV 17-21, 2008
CL Dallas, TX
SP Amer Phys Soc, Div Plasma Phys
DE explosions; helium; hydrogen; plasma production by laser; plasma shock
waves; plasma simulation; Rayleigh-Taylor instability
ID 2-DIMENSIONAL SIMULATIONS; HYDRODYNAMICS CODE; SUPERNOVA-REMNANTS; EARLY
EVOLUTION; LIGHT-CURVE; SN-1987A; GROWTH; ASTROPHYSICS; SYSTEM; LASERS
AB This paper describes experiments exploring the three-dimensional (3D) Rayleigh-Taylor instability at a blast-wave-driven interface. This experiment is well scaled to the He/H interface during the explosion phase of SN1987A. In the experiments, similar to 5 kJ of energy from the Omega laser was used to create a planar blast wave in a plastic disk, which is accelerated into a lower-density foam. These circumstances induce the Richtmyer-Meshkov instability and, after the shock passes the interface, the system quickly becomes dominated by the Rayleigh-Taylor instability. The plastic disk has an intentional pattern machined at the plastic/foam interface. This perturbation is 3D with a basic structure of two orthogonal sine waves with a wavelength of 71 mu m and an amplitude of 2.5 mu m. Additional long-wavelength modes with a wavelength of either 212 or 424 mu m are added onto the single-mode pattern. The addition of the long-wavelength modes was motivated by the results of previous experiments where material penetrated unexpectedly to the shock front, perhaps due to an unintended structure. The current experiments and simulations were performed to explore the effects of this unintended structure; however, we were unable to reproduce the previous results.
C1 [Kuranz, C. C.; Drake, R. P.; Grosskopf, M. J.; Budde, A.; Krauland, C.; Marion, D. C.; Visco, A. J.; Ditmar, J. R.] Univ Michigan, Ann Arbor, MI 48109 USA.
[Robey, H. F.; Remington, B. A.; Miles, A. R.; Cooper, A. B. R.; Sorce, C.] Lawrence Livermore Natl Lab, Livermore, CA 94550 USA.
[Plewa, T.] Florida State Univ, Dept Comp Sci, Tallahassee, FL 32306 USA.
[Hearn, N. C.] Univ Chicago, ASC Flash Ctr, Chicago, IL 60637 USA.
[Killebrew, K. L.] Sandia Natl Labs, Albuquerque, NM 87185 USA.
[Knauer, J. P.] Univ Rochester, Laser Energet Lab, Rochester, NY USA.
[Arnett, D.] Univ Arizona, Steward Observ, Tucson, AZ 85721 USA.
[Donajkowski, T.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
RP Kuranz, CC (reprint author), Univ Michigan, Ann Arbor, MI 48109 USA.
RI Plewa, Tomasz/C-1470-2010;
OI Plewa, Tomasz/0000-0002-1762-2565; Drake, R Paul/0000-0002-5450-9844
NR 43
TC 18
Z9 19
U1 1
U2 13
PU AMER INST PHYSICS
PI MELVILLE
PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA
SN 1070-664X
EI 1089-7674
J9 PHYS PLASMAS
JI Phys. Plasmas
PD MAY
PY 2009
VL 16
IS 5
AR 056310
DI 10.1063/1.3099320
PG 10
WC Physics, Fluids & Plasmas
SC Physics
GA 451WC
UT WOS:000266500600123
ER
PT J
AU Galli, GLJ
Shiels, HA
Brill, RW
AF Galli, Gina L. J.
Shiels, Holly A.
Brill, Richard W.
TI Temperature Sensitivity of Cardiac Function in Pelagic Fishes with
Different Vertical Mobilities: Yellowfin Tuna (Thunnus albacares),
Bigeye Tuna (Thunnus obesus), Mahimahi (Coryphaena hippurus), and
Swordfish (Xiphias gladius)
SO PHYSIOLOGICAL AND BIOCHEMICAL ZOOLOGY
LA English
DT Article
ID TROUT ONCORHYNCHUS-MYKISS; ISOLATED VENTRICULAR TRABECULAE; FORCE
FREQUENCY RELATIONSHIPS; ATLANTIC BLUEFIN TUNA; SARCOPLASMIC-RETICULUM;
RAINBOW-TROUT; ADRENERGIC-STIMULATION; THERMAL-ACCLIMATION; CALCIUM
CHANNELS; HAWAIIAN-ISLANDS
AB We measured the temperature sensitivity, adrenergic sensitivity, and dependence on sarcoplasmic reticulum (SR) Ca(2+) of ventricular muscle from pelagic fishes with different vertical mobility patterns: bigeye tuna (Thunnus obesus), yellowfin tuna (Thunnus albacares), and mahimahi (Coryphaena hippurus) and a single specimen from swordfish (Xiphias gladius). Ventricular muscle from the bigeye tuna and mahimahi exhibited a biphasic response to an acute decrease in temperature (from 26 degrees to 7 degrees C); twitch force and kinetic parameters initially increased and then declined. The magnitude of this response was larger in the bigeye tuna than in the mahimahi. Under steady state conditions at 26 degrees C, inhibition of SR Ca(2+) release and reuptake with ryanodine and thapsigargin decreased twitch force and kinetic parameters, respectively, in the bigeye tuna only. However, the initial inotropy associated with decreasing temperature was abolished by SR inhibition in both the bigeye tuna and the mahimahi. Application of adrenaline completely reversed the effects of ryanodine and thapsigargin, but this effect was diminished at cold temperatures. In the yellowfin tuna, temperature and SR inhibition had minor effects on twitch force and kinetics, while adrenaline significantly increased these parameters. Limited data suggest that swordfish ventricular muscle responds to acute temperature reduction, SR inhibition, and adrenergic stimulation in a manner similar to that of bigeye tuna ventricular muscle. In aggregate, our results show that the temperature sensitivity, SR dependence, and adrenergic sensitivity of pelagic fish hearts are species specific and that these differences reflect species-specific vertical mobility patterns.
C1 [Galli, Gina L. J.; Shiels, Holly A.] Univ Manchester, Fac Life Sci, Core Technol Facil, Manchester M13 9NT, Lancs, England.
[Brill, Richard W.] Virginia Inst Marine Sci, Natl Marine Fisheries Serv, NE Fisheries Sci Ctr, Cooperat Marine Educ & Res Program, Gloucester Point, VA 23062 USA.
RP Galli, GLJ (reprint author), Univ British Columbia, 2357 Main Mall, Vancouver, BC V6T 1Z4, Canada.
EM ggalli@interchange.ubc.ca
FU Biotechnology and Biological Sciences Research Council
NR 68
TC 19
Z9 19
U1 0
U2 9
PU UNIV CHICAGO PRESS
PI CHICAGO
PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA
SN 1522-2152
J9 PHYSIOL BIOCHEM ZOOL
JI Physiol. Biochem. Zool.
PD MAY-JUN
PY 2009
VL 82
IS 3
BP 280
EP 290
DI 10.1086/597484
PG 11
WC Physiology; Zoology
SC Physiology; Zoology
GA 431DZ
UT WOS:000265042800008
PM 19284308
ER
PT J
AU Blank, JG
Green, S
Blake, D
Valley, JW
Kita, NT
Treiman, A
Dobson, PF
AF Blank, J. G.
Green, Sj.
Blake, D.
Valley, J. W.
Kita, N. T.
Treiman, A.
Dobson, P. F.
TI An alkaline spring system within the Del Puerto Ophiolite (California,
USA): A Mars analog site
SO PLANETARY AND SPACE SCIENCE
LA English
DT Article; Proceedings Paper
CT Symposium on Exploring Mars and its Earth Analogues
CY JUN 19-23, 2007
CL Trento, ITALY
DE Mars analog; Dolomite; Alkaline springs; Biosignature
ID OXYGEN-ISOTOPE FRACTIONATION; 16S RIBOSOMAL-RNA; MODERN MARINE
STROMATOLITES; LITHIFIED MICRITIC LAMINAE; MARTIAN METEORITE ALH84001;
SULFATE-REDUCING BACTERIA; ALLAN HILLS 84001; MERIDIANI-PLANUM;
GEOCHEMICAL EVIDENCE; DOLOMITE FORMATION
AB Mars appears to have experienced little compositional differentiation of primitive lithosphere, and thus much of the surface of Mars is covered by mafic lavas. On Earth, mafic and ultramafic rocks present in ophiolites, oceanic crust and upper mantle that have been obducted onto land, are therefore good analogs for Mars. The characteristic mineralogy, aqueous geochemistry, and microbial communities of cold-water alkaline springs associated with these mafic and ultramafic rocks represent a particularly compelling analog for potential life-bearing systems. Serpentinization, the reaction of water with mafic minerals Such as olivine and pyroxene, yields fluids with unusual chemistry (Mg-OH and Ca-OH waters with pH values up to similar to 12), as well as heat and hydrogen gas that can sustain subsurface, chemosynthetic ecosystems. The recent observation of seeps from pole-facing crater and canyon walls in the higher Martian latitudes supports the hypothesis that even present conditions might allow for a rock-hosted chemosynthetic biosphere in near-surface regions of the Martian crust. The generation of methane within a zone of active serpentinization, through either abiogenic or biogenic processes, could account for the presence of methane detected in the Martian atmosphere. For all of these reasons, studies of terrestrial alkaline springs associated with mafic and ultramafic rocks are particularly timely. This study focuses on the alkaline Adobe Springs, emanating from mafic and ultramafic rocks of the California Coast Range, where a community of novel bacteria is associated with the precipitation of Mg-Ca carbonate cements. The carbonates may serve as a biosignature that could be used in the search for evidence of life on Mars. (C) 2008 Elsevier Ltd. All rights reserved.
C1 [Blank, J. G.] SETI Inst, Mountain View, CA 94043 USA.
[Blank, J. G.; Green, Sj.; Blake, D.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA.
[Valley, J. W.; Kita, N. T.] Univ Wisconsin, Dept Geol & Geophys, Madison, WI 53706 USA.
[Treiman, A.] Lunar & Planetary Inst, Houston, TX 77058 USA.
[Dobson, P. F.] Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA.
RP Blank, JG (reprint author), SETI Inst, 515 N Whisman Rd, Mountain View, CA 94043 USA.
EM jblank@seti.org
RI Valley, John/B-3466-2011; Green, Stefan/C-8980-2011; Dobson,
Patrick/D-8771-2015; Kita, Noriko/H-8035-2016;
OI Valley, John/0000-0003-3530-2722; Dobson, Patrick/0000-0001-5031-8592;
Kita, Noriko/0000-0002-0204-0765; Green, Stefan/0000-0003-2781-359X
NR 84
TC 34
Z9 37
U1 0
U2 20
PU PERGAMON-ELSEVIER SCIENCE LTD
PI OXFORD
PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND
SN 0032-0633
J9 PLANET SPACE SCI
JI Planet Space Sci.
PD MAY
PY 2009
VL 57
IS 5-6
BP 533
EP 540
DI 10.1016/j.pss.2008.11.018
PG 8
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 456QX
UT WOS:000266863400003
ER
PT J
AU Burr, DM
Bruno, BC
Lanagan, PD
Glaze, LS
Jaeger, WL
Soare, RJ
Tseung, JMWB
Skinner, JA
Baloga, SM
AF Burr, Devon M.
Bruno, Barbara C.
Lanagan, Peter D.
Glaze, Lori S.
Jaeger, Windy L.
Soare, Richard J.
Tseung, Jean-Michel Wan Bun
Skinner, James A., Jr.
Baloga, Stephen M.
TI Mesoscale raised rim depressions (MRRDs) on Earth: A review of the
characteristics, processes, and spatial distributions of analogs for
Mars
SO PLANETARY AND SPACE SCIENCE
LA English
DT Article; Proceedings Paper
CT Symposium on Exploring Mars and its Earth Analogues
CY JUN 19-23, 2007
CL Trento, ITALY
DE Mars; Surface; Terrestrial analogs; Spatial analysis
ID WESTERN-ARCTIC-COAST; MUD VOLCANISM; GROUND ICE; HYDROVOLCANIC
EXPLOSIONS; ACCRETIONARY COMPLEX; COLUMBIA PLATEAU; ATHABASCA VALLES;
NORTHERN PLAINS; UTOPIA PLANITIA; RING STRUCTURES
AB Fields of mesoscale raised rim depressions (MRRDs) of various origins are found on Earth and Mars. Examples include rootless cones, mud volcanoes, collapsed pingos, rimmed kettle holes, and basaltic ring structures. Correct identification of MRRDs on Mars is valuable because different MRRD types have different geologic and/or climatic implications and are often associated with volcanism and/or water, which may provide locales for biotic or prebiotic activity. In order to facilitate correct identification of fields of MRRDs on Mars and their implications, this work provides a review of common terrestrial MRRD types that. Occur in fields. in this review, MRRDs by formation mechanism, including hydrovolcanic (phreatomagmatic cones, basaltic ring structures), sedimentological (mud volcanoes), and ice-related (pingos, volatile ice-block forms) mechanisms. For each broad mechanism, we present a comparative synopsis of (i) morphology and observations, (ii) physical formation processes, and (iii) published hypothesized locations on Mars. Because the morphology for MRRDs may be ambiguous, an additional tool is provided for distinguishing fields of MRRDs by origin on Mars, namely, spatial distribution analyses for MRRDs within fields on Earth. We find that MRRDs have both distinguishing and similar characteristics, and observation that applies both to their mesoscale morphology and to their spatial distribution statistics. Thus, this review provides tools for distinguishing between various MRRDs, while highlighting the utility of the Multiple working hypotheses approach. (C) 2008 Elsevier Ltd. All rights reserved.
C1 [Burr, Devon M.] Univ Tennessee, Dept Earth & Planetary Sci, Knoxville, TN 37996 USA.
[Burr, Devon M.] SETI Inst, Mountain View, CA 94043 USA.
[Bruno, Barbara C.] Univ Hawaii, Sch Ocean & Earth Sci & Technol, Honolulu, HI 96822 USA.
[Bruno, Barbara C.; Glaze, Lori S.; Baloga, Stephen M.] Proxemy Res, Gaithersburg, MD 20882 USA.
[Lanagan, Peter D.] Coll So Nevada, Henderson, NV 89002 USA.
[Glaze, Lori S.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
[Jaeger, Windy L.; Skinner, James A., Jr.] US Geol Survey, Astrogeol Team, Flagstaff, AZ 86001 USA.
[Soare, Richard J.] Concordia Univ, Dept Geog & Planning & Environm, Montreal, PQ H3G 1M8, Canada.
[Soare, Richard J.] Univ Calgary, Dept Geog, Calgary, AB T2N 1N4, Canada.
[Soare, Richard J.] Univ Western Ontario, Dept Earth Sci & Phys & Astron, London, ON N6A 5B7, Canada.
[Tseung, Jean-Michel Wan Bun] Dawson Coll, Dept Geog, Montreal, PQ H3Z 1A4, Canada.
RP Burr, DM (reprint author), Univ Tennessee, Dept Earth & Planetary Sci, 1412 Circle Dr, Knoxville, TN 37996 USA.
EM dburr1@utk.edu
RI Glaze, Lori/D-1314-2012; Skinner, James/M-7966-2014
NR 153
TC 20
Z9 20
U1 1
U2 5
PU PERGAMON-ELSEVIER SCIENCE LTD
PI OXFORD
PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND
SN 0032-0633
J9 PLANET SPACE SCI
JI Planet Space Sci.
PD MAY
PY 2009
VL 57
IS 5-6
SI SI
BP 579
EP 596
DI 10.1016/j.pss.2008.11.011
PG 18
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 456QX
UT WOS:000266863400007
ER
PT J
AU Dohm, JM
Baker, VR
Boynton, WV
Fairen, AG
Ferris, JC
Finch, M
Furfaro, R
Hare, TM
Janes, DM
Kargel, JS
Karunatillake, S
Keller, J
Kerry, K
Kim, KJ
Komatsu, G
Mahaney, WC
Schulze-Makuch, D
Marinangeli, L
Ori, GG
Ruiz, J
Wheelock, SJ
AF Dohm, James M.
Baker, Victor R.
Boynton, William V.
Fairen, Alberto G.
Ferris, Justin C.
Finch, Michael
Furfaro, Roberto
Hare, Trent M.
Janes, Daniel M.
Kargel, Jeffrey S.
Karunatillake, Suniti
Keller, John
Kerry, Kris
Kim, Kyeong J.
Komatsu, Goro
Mahaney, William C.
Schulze-Makuch, Dirk
Marinangeli, Lucia
Ori, Gian G.
Ruiz, Javier
Wheelock, Shawn J.
TI GRS evidence and the possibility of paleooceans on Mars
SO PLANETARY AND SPACE SCIENCE
LA English
DT Article; Proceedings Paper
CT Symposium on Exploring Mars and its Earth Analogues
CY JUN 19-23, 2007
CL Trento, ITALY
DE Mars; Gamma-ray spectrometer; Oceans; Water; Elemental; Hydrogeology
ID MARTIAN NORTHERN PLAINS; ALTIMETER MOLA DATA; MERIDIANI-PLANUM; AQUEOUS
SEDIMENTATION; GLOBAL DISTRIBUTION; CHAOTIC OBLIQUITY; ROOTLESS CONES;
GROUND ICE; WATER; DEPOSITS
AB The Gamma Ray Spectrometer (Mars Odyssey spacecraft) has revealed elemental distributions of potassium (K), thorium (Th), and iron (Fe) on Mars that require fractionation of K (and possibly Th and Fe) consistent with aqueous activity. This includes weathering, evolution of soils, and transport, sorting, and deposition, as well as with the location of first-order geomorphological demarcations identified as possible paleoocean boundaries. The element abundances occur in patterns consistent with weathering in situ and possible presence of relict or exhumed paleosols, deposition of weathered materials (salts and clastic minerals), and weathering/transport under neutral to acidic brines. The abundances are explained by hydrogeology consistent with the possibly overlapping alternatives of paleooceans and/or heterogeneous rock compositions from diverse provenances (e.g., differing igneous compositions). (C) 2008 Elsevier Ltd. All rights reserved.
C1 [Dohm, James M.; Baker, Victor R.; Kargel, Jeffrey S.; Wheelock, Shawn J.] Univ Arizona, Dept Hydrol & Water Resources, Tucson, AZ 85721 USA.
[Dohm, James M.; Baker, Victor R.; Boynton, William V.; Finch, Michael; Janes, Daniel M.; Kerry, Kris] Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA.
[Fairen, Alberto G.] NASA, Ames Res Ctr, Space Sci & Astrobiol Div, Moffett Field, CA 94035 USA.
[Ferris, Justin C.] US Geol Survey, Calif Water Sci Ctr, Sacramento, CA 95819 USA.
[Furfaro, Roberto] Univ Arizona, Dept Aerosp & Mech Engn, Tucson, AZ 85721 USA.
[Hare, Trent M.] US Geol Survey, Flagstaff, AZ 86001 USA.
[Karunatillake, Suniti] Cornell Univ, Ctr Radiophys & Space Res, Ithaca, NY 14853 USA.
[Keller, John] Calif Polytech State Univ San Luis Obispo, Dept Phys, San Luis Obispo, CA USA.
[Kim, Kyeong J.] Korea Inst Geosci & Mineral Resources, Geol & Environm Hazards Div, Taejon, South Korea.
[Komatsu, Goro; Marinangeli, Lucia; Ori, Gian G.] Univ G DAnnunzio, Int Res Sch Planetary Sci, Pescara, Italy.
[Mahaney, William C.] York Univ, Atkinson Coll, Geomorphol & Pedol Lab, N York, ON M3J 1P3, Canada.
[Mahaney, William C.] Quaternary Surveys, Thornhill, ON L4J 1J4, Canada.
[Schulze-Makuch, Dirk] Washington State Univ, Sch Earth & Environm Sci, Pullman, WA 99164 USA.
[Ruiz, Javier] CSIC, Museo Nacl Ciencias Nat, E-28006 Madrid, Spain.
RP Dohm, JM (reprint author), Univ Arizona, Dept Hydrol & Water Resources, Tucson, AZ 85721 USA.
EM jmd@hwr.arizona.edu
RI Karunatillake, Suniti/A-5934-2009; Wheelock, Shawn/A-7627-2010; Dohm,
James/A-3831-2014; Ruiz, Javier/P-3975-2015; Komatsu, Goro/I-7822-2012;
OI Karunatillake, Suniti/0000-0001-9891-1432; Ruiz,
Javier/0000-0002-3937-8380; Komatsu, Goro/0000-0003-4155-108X; Kim,
Kyeong J/0000-0001-6220-8411; Hare, Trent/0000-0001-8842-389X;
Schulze-Makuch, Dirk/0000-0002-1923-9746; ORI, Gian
Gabriele/0000-0002-6460-1476
NR 146
TC 40
Z9 41
U1 1
U2 12
PU PERGAMON-ELSEVIER SCIENCE LTD
PI OXFORD
PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND
SN 0032-0633
J9 PLANET SPACE SCI
JI Planet Space Sci.
PD MAY
PY 2009
VL 57
IS 5-6
SI SI
BP 664
EP 684
DI 10.1016/j.pss.2008.10.008
PG 21
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 456QX
UT WOS:000266863400016
ER
PT J
AU Shin, DS
Jung, YD
AF Shin, Dong-Soo
Jung, Young-Dae
TI Nonthermal and screening effects on photoionizations in Lorentzian
plasmas
SO PLASMA PHYSICS AND CONTROLLED FUSION
LA English
DT Article
AB The nonthermal and plasma screening effects on the x-ray photoionization process are investigated in astrophysical Lorentzian plasmas. The screened atomic wave function and energy eigenvalue of the target ion in Lorentzian plasmas are obtained by the Rayleigh-Ritz variational method. The x-ray retardation and screened Coulomb corrections are considered to obtain a photoionization cross section as a function of the spectral index and plasma parameters. It is shown that the nonthermal character of the Lorentzian plasma suppresses the photoionization cross section. Hence, the photoionization cross sections in nonthermal plasmas are found to be always smaller than those in thermal plasmas. It is also shown that the plasma screening effect is more significant for small spectral indices. In addition, the nonthermal effect on the photoionization cross section is found to be decreased with an increase in the Debye length.
C1 [Shin, Dong-Soo; Jung, Young-Dae] Hanyang Univ, Dept Appl Phys, Ansan 426791, Kyunggi Do, South Korea.
[Jung, Young-Dae] NASA, George C Marshall Space Flight Ctr, Natl Space Sci & Technol Ctr, Huntsville, AL 35805 USA.
RP Shin, DS (reprint author), Hanyang Univ, Dept Appl Phys, Ansan 426791, Kyunggi Do, South Korea.
EM ydjung@hanyang.ac.kr
NR 24
TC 0
Z9 0
U1 0
U2 0
PU IOP PUBLISHING LTD
PI BRISTOL
PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND
SN 0741-3335
EI 1361-6587
J9 PLASMA PHYS CONTR F
JI Plasma Phys. Control. Fusion
PD MAY
PY 2009
VL 51
IS 5
AR 055007
DI 10.1088/0741-3335/51/5/055007
PG 8
WC Physics, Fluids & Plasmas
SC Physics
GA 438VQ
UT WOS:000265584300007
ER
PT J
AU Rubin, B
Farnell, C
Williams, J
Vaughn, J
Schneider, T
Ferguson, D
AF Rubin, B.
Farnell, C.
Williams, J.
Vaughn, J.
Schneider, T.
Ferguson, D.
TI Magnetic filter type plasma source for ground-based simulation of low
earth orbit environment
SO PLASMA SOURCES SCIENCE & TECHNOLOGY
LA English
DT Article
ID ION-SOURCE; ELECTRICAL BREAKDOWN; TECHNOLOGY; COLLECTION; SPACECRAFT;
BEAMS; ARRAY
AB Simulation of the low Earth orbit (LEO) plasma environment in ground-based vacuum facilities is important for studies of spacecraft interaction with ionospheric plasmas. In this paper we describe the design and performance of a magnetic filter-equipped plasma source. Experimental data collected in the expanding plasma downstream of the source suggest it is a good candidate for use as a LEO plasma simulator in that the expanding plasma has a very low electron temperature and contains streaming ions-the plasma environment encountered by satellites in LEO. Adjustable plasma source operating conditions of flow rate, discharge current and discharge voltage enable production of plasma electron temperatures over the range from 0.17 to 0.35 eV and streaming ion energies over the range from 1 to 4 eV.
C1 [Rubin, B.; Farnell, C.; Williams, J.] Colorado State Univ, Dept Mech Engn, Ft Collins, CO 80523 USA.
[Vaughn, J.; Schneider, T.; Ferguson, D.] NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA.
RP Williams, J (reprint author), Colorado State Univ, Dept Mech Engn, Ft Collins, CO 80523 USA.
EM john.d.williams@colostate.edu
FU NASA Space Environment and Effects
FX Funding for the final development of the plasma source was provided by
the NASA Space Environment and Effects (SEE) Program. The authors would
like to thank Kenneth Wright (University of Alabama in Huntsville) for
assistance in analyzing the plasma data.
NR 25
TC 6
Z9 6
U1 0
U2 2
PU IOP PUBLISHING LTD
PI BRISTOL
PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND
SN 0963-0252
J9 PLASMA SOURCES SCI T
JI Plasma Sources Sci. Technol.
PD MAY
PY 2009
VL 18
IS 2
AR 025015
DI 10.1088/0963-0252/18/2/025015
PG 9
WC Physics, Fluids & Plasmas
SC Physics
GA 438UL
UT WOS:000265580800018
ER
PT J
AU Slavin, JA
Acuna, MH
Anderson, BJ
Baker, DN
Benna, M
Boardsen, SA
Gloeckler, G
Gold, RE
Ho, GC
Korth, H
Krimigis, SM
McNutt, RL
Raines, JM
Sarantos, M
Schriver, D
Solomon, SC
Travnicek, P
Zurbuchen, TH
AF Slavin, James A.
Acuna, Mario H.
Anderson, Brian J.
Baker, Daniel N.
Benna, Mehdi
Boardsen, Scott A.
Gloeckler, George
Gold, Robert E.
Ho, George C.
Korth, Haje
Krimigis, Stamatios M.
McNutt, Ralph L., Jr.
Raines, Jim M.
Sarantos, Menelaos
Schriver, David
Solomon, Sean C.
Travnicek, Pavel
Zurbuchen, Thomas H.
TI MESSENGER Observations of Magnetic Reconnection in Mercury's
Magnetosphere
SO SCIENCE
LA English
DT Article
ID GEOTAIL OBSERVATIONS; EARTHS MAGNETOPAUSE; FLUX-TRANSFER; 1ST FLYBY;
FIELD; SUBSTORMS; MAGNETOTAIL; TAIL
AB Solar wind energy transfer to planetary magnetospheres and ionospheres is controlled by magnetic reconnection, a process that determines the degree of connectivity between the interplanetary magnetic field (IMF) and a planet's magnetic field. During MESSENGER's second flyby of Mercury, a steady southward IMF was observed and the magnetopause was threaded by a strong magnetic field, indicating a reconnection rate similar to 10 times that typical at Earth. Moreover, a large flux transfer event was observed in the magnetosheath, and a plasmoid and multiple traveling compression regions were observed in Mercury's magnetotail, all products of reconnection. These observations indicate that Mercury's magnetosphere is much more responsive to IMF direction and dominated by the effects of reconnection than that of Earth or the other magnetized planets.
C1 [Slavin, James A.; Boardsen, Scott A.; Sarantos, Menelaos] NASA, Goddard Space Flight Ctr, Heliophys Sci Div, Greenbelt, MD 20771 USA.
[Acuna, Mario H.; Benna, Mehdi] NASA, Goddard Space Flight Ctr, Solar Syst Explorat Div, Greenbelt, MD 20771 USA.
[Anderson, Brian J.; Gold, Robert E.; Ho, George C.; Korth, Haje; Krimigis, Stamatios M.; McNutt, Ralph L., Jr.] Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA.
[Baker, Daniel N.] Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80303 USA.
[Benna, Mehdi; Boardsen, Scott A.] Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA.
[Gloeckler, George; Raines, Jim M.; Zurbuchen, Thomas H.] Univ Maryland, Dept Astron, College Pk, MD 20742 USA.
[Gloeckler, George] Univ Michigan, Dept Atmospher Ocean & Space Sci, Ann Arbor, MI 48109 USA.
[Krimigis, Stamatios M.] Acad Athens, Athens 11527, Greece.
[Schriver, David; Travnicek, Pavel] Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90024 USA.
[Solomon, Sean C.] Carnegie Inst Sci, Dept Terr Magnetism, Washington, DC 20015 USA.
[Travnicek, Pavel] Acad Sci Czech Republic, Inst Astron, Prague 14131, Czech Republic.
RP Slavin, JA (reprint author), NASA, Goddard Space Flight Ctr, Heliophys Sci Div, Greenbelt, MD 20771 USA.
EM james.a.slavin@nasa.gov
RI McNutt, Ralph/E-8006-2010; Anderson, Brian/I-8615-2012; Slavin,
James/H-3170-2012; Sarantos, Menelaos/H-8136-2013; Travnicek,
Pavel/G-8608-2014; Ho, George/G-3650-2015; Benna, Mehdi/F-3489-2012
OI McNutt, Ralph/0000-0002-4722-9166; Slavin, James/0000-0002-9206-724X;
Ho, George/0000-0003-1093-2066;
FU NASA Discovery Program [NAS5-97271]; Johns Hopkins University Applied
Physics Laboratory; Carnegie Institution of Washington [NASW-00002]
FX We deeply mourn the loss of our colleague and MESSENGER Co-Investigator
Mario Acuna during the preparation of this manuscript; his many
contributions to the MESSENGER mission and the space science community
live on. We also thank all who contributed to the success of the first
and second MESSENGER flybys of Mercury. Data visualization and graphics
support by J. Feggans, C. Liebrecht, and M. Marosy are gratefully
acknowledged. The MESSENGER project is supported by the NASA Discovery
Program under contracts NAS5-97271 to the Johns Hopkins University
Applied Physics Laboratory and NASW-00002 to the Carnegie Institution of
Washington.
NR 26
TC 107
Z9 107
U1 2
U2 13
PU AMER ASSOC ADVANCEMENT SCIENCE
PI WASHINGTON
PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA
SN 0036-8075
EI 1095-9203
J9 SCIENCE
JI Science
PD MAY 1
PY 2009
VL 324
IS 5927
BP 606
EP 610
DI 10.1126/science.1172011
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA 439DW
UT WOS:000265608800034
PM 19407194
ER
PT J
AU Catling, DC
Zahnle, KL
AF Catling, David C.
Zahnle, Kevin L.
TI The Planetary Air Leak
SO SCIENTIFIC AMERICAN
LA English
DT Article
C1 [Catling, David C.] NASA, Ames Res Ctr, Washington, DC USA.
OI Catling, David/0000-0001-5646-120X
NR 3
TC 5
Z9 5
U1 1
U2 1
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 MAY
PY 2009
VL 300
IS 5
BP 36
EP 43
PG 8
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA 434LO
UT WOS:000265276400031
PM 19438047
ER
PT J
AU Christian, ER
Kaiser, ML
Kucera, TA
St Cyr, OC
van Driel-Gesztelyi, L
Mandrini, CH
AF Christian, Eric R.
Kaiser, Michael L.
Kucera, Therese A.
St Cyr, O. C.
van Driel-Gesztelyi, Lidia
Mandrini, Cristina H.
TI STEREO SCIENCE RESULTS AT SOLAR MINIMUM - Preface
SO SOLAR PHYSICS
LA English
DT Editorial Material
C1 [Christian, Eric R.; Kaiser, Michael L.; Kucera, Therese A.; St Cyr, O. C.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
[van Driel-Gesztelyi, Lidia] Observ Paris, CNRS, UMR 8109, LESIA, F-92195 Meudon, France.
[van Driel-Gesztelyi, Lidia] Univ Coll London, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England.
[van Driel-Gesztelyi, Lidia] Hungarian Acad Sci, Konkoly Observ Budapest, Budapest, Hungary.
[Mandrini, Cristina H.] Univ Buenos Aires, CONICET, Inst Astron & Fis Espacio, RA-1428 Buenos Aires, DF, Argentina.
RP Christian, ER (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
EM Eric.R.Christian@nasa.gov; Therese.A.Kucera@nasa.gov;
Chris.StCyr@nasa.gov; Lidia.vanDriel@obspm.fr; mandrini@iafe.uba.ar
RI Kucera, Therese/C-9558-2012; Christian, Eric/D-4974-2012
OI Christian, Eric/0000-0003-2134-3937
NR 0
TC 0
Z9 0
U1 0
U2 1
PU SPRINGER
PI DORDRECHT
PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS
SN 0038-0938
J9 SOL PHYS
JI Sol. Phys.
PD MAY
PY 2009
VL 256
IS 1-2
BP 1
EP 2
DI 10.1007/s11207-009-9365-2
PG 2
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 438OC
UT WOS:000265563900001
ER
PT J
AU Liewer, PC
De Jong, EM
Hall, JR
Howard, RA
Thompson, WT
Culhane, JL
Bone, L
van Driel-Gesztelyi, L
AF Liewer, P. C.
De Jong, E. M.
Hall, J. R.
Howard, R. A.
Thompson, W. T.
Culhane, J. L.
Bone, L.
van Driel-Gesztelyi, L.
TI Stereoscopic Analysis of the 19 May 2007 Erupting Filament
SO SOLAR PHYSICS
LA English
DT Article
DE Corona; Prominences; Filaments; Eruptions; Stereoscopy
ID MAGNETIC CLOUDS; SOLAR-FLARES; PROMINENCES; DYNAMICS; SECCHI; EUVI
AB A filament eruption, accompanied by a B9.5 flare, coronal dimming, and an EUV wave, was observed by the Solar TERrestrial Relations Observatory (STEREO) on 19 May 2007, beginning at about 13:00 UT. Here, we use observations from the SECCHI/EUVI telescopes and other solar observations to analyze the behavior and geometry of the filament before and during the eruption. At this time, STEREO A and B were separated by about 8.5A degrees, sufficient to determine the three-dimensional structure of the filament using stereoscopy. The filament could be followed in SECCHI/EUVI 304 A... stereoscopic data from about 12 hours before to about 2 hours after the eruption, allowing us to determine the 3D trajectory of the erupting filament. From the 3D reconstructions of the filament and the chromospheric ribbons in the early stage of the eruption, simultaneous heating of both the rising filamentary material and the chromosphere directly below is observed, consistent with an eruption resulting from magnetic reconnection below the filament. Comparisons of the filament during eruption in 304 A... and H alpha show that when it becomes emissive in He II, it tends to disappear in H alpha , indicating that the disappearance probably results from heating or motion, not loss, of filamentary material.
C1 [Liewer, P. C.; De Jong, E. M.; Hall, J. R.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
[Howard, R. A.] USN, Res Lab, Washington, DC 20375 USA.
[Thompson, W. T.] Adnet Syst Inc, Lanham, MD 20706 USA.
[Culhane, J. L.; Bone, L.; van Driel-Gesztelyi, L.] Univ Coll London, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England.
[van Driel-Gesztelyi, L.] Observ Paris, CNRS, FRE 2461, LESIA, F-92195 Meudon, France.
Hungarian Acad Sci, Konkoly Observ Budapest, Budapest, Hungary.
RP Liewer, PC (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA.
EM Paulett.Liewer@jpl.nasa.gov
RI Thompson, William/D-7376-2012
FU NASA; USAF Space Test Program; Office of Naval Research; European
Commission [218816]
FX We thank K.E.J. Kilpua, Y.Li, J. Luhmann, B. Lynch, S. Martin, O.
Penasco, and A. Vourlidas for very valuable conversation on this solar
event. We thank N. Rich, S. Suzuki, and J.-P. Wuesler for their help
with the SECCHI/EUVI data. The STEREO/SECCHI data used here are produced
by an international consortium of the Naval Research Laboratory (USA),
Lockheed-Martin Solar and Astrophysics Lab (USA), NASA Goddard Space
Flight Center (USA), Rutherford Appleton Laboratory (UK), University of
Birmingham ( UK), Max-Planck-Institut fur Sonnensystemforschung
(Germany), Centre Spatiale de Liege (Belgium), Institut d'Optique
Theorique et Appliquee (France), Institut d'Astrophysique Spatiale
(France). The USA institutions were funded by NASA; the UK institutions
by Particle Physics and Astronomy Research Council (PPARC); the German
institutions by Deutsches Zentrum fur Luft- und Raumfahrt e. V. (DLR);
the Belgian institutions by Belgian Science Policy Office; the French
institutions by Centre National d'Etudes Spatiales (CNES) and the Centre
National de la Recherche Scientifique (CNRS). The NRL effort was also
supported by the USAF Space Test Program and the Office of Naval
Research. A portion of this work was carried out at the Jet Propulsion
Laboratory, California Institute of Technology under a contract with
NASA. J.L.C. acknowledges the award of a Leverhulme Emeritus Fellowship.
Financial support for LvDG by the European Commission through the
SOTERIA Network (EU FP7 Space Science Project No. 218816) is gratefully
acknowledged.
NR 25
TC 60
Z9 62
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 MAY
PY 2009
VL 256
IS 1-2
BP 57
EP 72
DI 10.1007/s11207-009-9363-4
PG 16
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 438OC
UT WOS:000265563900004
ER
PT J
AU Rouillard, AP
Savani, NP
Davies, JA
Lavraud, B
Forsyth, RJ
Morley, SK
Opitz, A
Sheeley, NR
Burlaga, LF
Sauvaud, JA
Simunac, KDC
Luhmann, JG
Galvin, AB
Crothers, SR
Davis, CJ
Harrison, RA
Lockwood, M
Eyles, CJ
Bewsher, D
Brown, DS
AF Rouillard, A. P.
Savani, N. P.
Davies, J. A.
Lavraud, B.
Forsyth, R. J.
Morley, S. K.
Opitz, A.
Sheeley, N. R.
Burlaga, L. F.
Sauvaud, J. -A.
Simunac, K. D. C.
Luhmann, J. G.
Galvin, A. B.
Crothers, S. R.
Davis, C. J.
Harrison, R. A.
Lockwood, M.
Eyles, C. J.
Bewsher, D.
Brown, D. S.
TI A Multispacecraft Analysis of a Small-Scale Transient Entrained by Solar
Wind Streams
SO SOLAR PHYSICS
LA English
DT Article
DE Sun: magnetic field; Sun: corotating interaction regions; Interplanetary
medium: coronal mass ejection
ID CORONAL MASS EJECTIONS; MAGNETIC CLOUDS; HOLES; INTERFACES; EXPLORER;
SECCHI; CYCLE; EARTH; FIELD
AB The images taken by the Heliospheric Imagers (HIs), part of the SECCHI imaging package onboard the pair of STEREO spacecraft, provide information on the radial and latitudinal evolution of the plasma compressed inside corotating interaction regions (CIRs). A plasma density wave imaged by the HI instrument onboard STEREO-B was found to propagate towards STEREO-A, enabling a comparison between simultaneous remote-sensing and in situ observations of its structure to be performed. In situ measurements made by STEREO-A show that the plasma density wave is associated with the passage of a CIR. The magnetic field compressed after the CIR stream interface (SI) is found to have a planar distribution. Minimum variance analysis of the magnetic field vectors shows that the SI is inclined at 54A degrees to the orbital plane of the STEREO-A spacecraft. This inclination of the CIR SI is comparable to the inclination of the associated plasma density wave observed by HI. A small-scale magnetic cloud with a flux rope topology and radial extent of 0.08 AU is also embedded prior to the SI. The pitch-angle distribution of suprathermal electrons measured by the STEREO-A SWEA instrument shows that an open magnetic field topology in the cloud replaced the heliospheric current sheet locally. These observations confirm that HI observes CIRs in difference images when a small-scale transient is caught up in the compression region.
C1 [Rouillard, A. P.; Lockwood, M.] Univ Southampton, Sch Phys & Astron, Space Environm Phys Grp, Southampton SO17 1BJ, Hants, England.
[Rouillard, A. P.; Davies, J. A.; Crothers, S. R.; Davis, C. J.; Harrison, R. A.; Lockwood, M.; Eyles, C. J.; Bewsher, D.] Rutherford Appleton Lab, Space Sci & Technol Dept, Chilton OX11 0QX, Oxon, England.
[Savani, N. P.; Forsyth, R. J.] Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2BW, England.
[Lavraud, B.; Opitz, A.; Sauvaud, J. -A.] Univ Toulouse UPS, Ctr Etud Spatiale Rayonnements, Toulouse, France.
[Lavraud, B.; Opitz, A.; Sauvaud, J. -A.] CNRS, UMR 5187, Toulouse, France.
[Morley, S. K.] Univ Newcastle, Ctr Space Phys, Newcastle, NSW 2308, Australia.
[Sheeley, N. R.] USN, Res Lab, Div Space Sci, Washington, DC 20375 USA.
[Burlaga, L. F.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
[Simunac, K. D. C.; Galvin, A. B.] Univ New Hampshire, Inst Study Earth Oceans & Space, Durham, NH 03824 USA.
[Luhmann, J. G.] Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA.
[Eyles, C. J.] Univ Valencia, Grp Astron & Ciencias Espacio, Valencia, Spain.
[Bewsher, D.; Brown, D. S.] Aberystwyth Univ, Inst Math & Phys Sci, Aberystwyth SY23 3BZ, Dyfed, Wales.
RP Rouillard, AP (reprint author), Univ Southampton, Sch Phys & Astron, Space Environm Phys Grp, Southampton SO17 1BJ, Hants, England.
EM alexisrouillard@yahoo.co.uk
RI Morley, Steven/A-8321-2008; Lockwood, Mike/G-1030-2011; Galvin,
Antoinette/A-6114-2013; Savani, Neel/G-4066-2014; Scott,
Christopher/H-8664-2012;
OI Bewsher, Danielle/0000-0002-6351-5170; Morley,
Steven/0000-0001-8520-0199; Lockwood, Mike/0000-0002-7397-2172; Savani,
Neel/0000-0002-1916-7877; Scott, Christopher/0000-0001-6411-5649; Brown,
Daniel/0000-0002-1618-8816
FU STFC (UK)
FX This work was funded by STFC (UK). The STEREO/SECCHI data are produced
by a consortium of RAL (UK), NRL (USA), LMSAL (USA), GSFC (USA), MPS
(Germany), CSL (Belgium), IOTA (France) and IAS (France). The PLASTIC
and IMPACT data are produced by a consortium of the CESR (France), the
University of New Hampshire and the University of California.
NR 41
TC 59
Z9 59
U1 0
U2 5
PU SPRINGER
PI DORDRECHT
PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS
SN 0038-0938
EI 1573-093X
J9 SOL PHYS
JI Sol. Phys.
PD MAY
PY 2009
VL 256
IS 1-2
BP 307
EP 326
DI 10.1007/s11207-009-9329-6
PG 20
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 438OC
UT WOS:000265563900018
ER
PT J
AU Opitz, A
Karrer, R
Wurz, P
Galvin, AB
Bochsler, P
Blush, LM
Daoudi, H
Ellis, L
Farrugia, CJ
Giammanco, C
Kistler, LM
Klecker, B
Kucharek, H
Lee, MA
Mobius, E
Popecki, M
Sigrist, M
Simunac, K
Singer, K
Thompson, B
Wimmer-Schweingruber, RF
AF Opitz, A.
Karrer, R.
Wurz, P.
Galvin, A. B.
Bochsler, P.
Blush, L. M.
Daoudi, H.
Ellis, L.
Farrugia, C. J.
Giammanco, C.
Kistler, L. M.
Klecker, B.
Kucharek, H.
Lee, M. A.
Moebius, E.
Popecki, M.
Sigrist, M.
Simunac, K.
Singer, K.
Thompson, B.
Wimmer-Schweingruber, R. F.
TI Temporal Evolution of the Solar Wind Bulk Velocity at Solar Minimum by
Correlating the STEREO A and B PLASTIC Measurements
SO SOLAR PHYSICS
LA English
DT Article
DE Solar wind; STEREO; Plasma; Multipoint spacecraft observations
ID PLASMA CORRELATIONS; SPEED VARIATIONS
AB The two STEREO spacecraft with nearly identical instrumentation were launched near solar activity minimum and they separate by about 45A degrees per year, providing a unique tool to study the temporal evolution of the solar wind. We analyze the solar wind bulk velocity measured by the two PLASTIC plasma instruments onboard the two STEREO spacecraft. During the first half year of our measurements (March -aEuro parts per thousand August 2007) we find the typical alternating slow and fast solar wind stream pattern expected at solar minimum. To evaluate the temporal evolution of the solar wind bulk velocity we exclude the spatial variations and calculate the correlation between the solar wind bulk velocity measured by the two spacecraft. We account for the different spacecraft positions in radial distance and longitude by calculating the corresponding time lag. After adjusting for this time lag we compare the solar wind bulk velocity measurements at the two spacecraft and calculate the correlation between the two time-shifted datasets. We show how this correlation decreases as the time difference between two corresponding measurements increases. As a result, the characteristic temporal changes in the solar wind bulk velocity can be inferred. The obtained correlation is 0.95 for a time lag of 0.5 days and 0.85 for 2 days.
C1 [Opitz, A.] Univ Toulouse, CNRS, UPS, Ctr Etud Spatiale Rayonnements, Toulouse, France.
[Opitz, A.; Karrer, R.; Wurz, P.; Bochsler, P.; Blush, L. M.; Daoudi, H.; Giammanco, C.; Sigrist, M.] Univ Bern, Inst Phys, Dept Space Sci & Planetol, Bern, Switzerland.
[Galvin, A. B.; Ellis, L.; Farrugia, C. J.; Kistler, L. M.; Kucharek, H.; Lee, M. A.; Moebius, E.; Popecki, M.; Simunac, K.; Singer, K.] Univ New Hampshire, SSC, Durham, NH 03824 USA.
[Klecker, B.] MPI Extraterr Phys, Garching, Germany.
[Thompson, B.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
[Wimmer-Schweingruber, R. F.] Univ Kiel, Inst Expt & Appl Phys, Kiel, Germany.
RP Opitz, A (reprint author), Univ Toulouse, CNRS, UPS, Ctr Etud Spatiale Rayonnements, Toulouse, France.
EM opitz@cesr.fr
RI Thompson, Barbara/C-9429-2012; Galvin, Antoinette/A-6114-2013;
OI Giammanco, Corrado/0000-0001-5405-0095; Moebius,
Eberhard/0000-0002-2745-6978
FU Swiss National Fund for the University of Bern; NASA; CNES
FX The authors would like to thank Jack T. Gosling and Alexis P. Rouillard
for helpful discussions, as well as Christopher T. Russell for his
comments. This work was supported by the Swiss National Fund for the
University of Bern. It was also supported by the NASA STEREO/PLASTIC
Grant for the University of New Hampshire and by a CNES Grant for CESR
(CNRS-UPS). The authors acknowledge contributions from the entire STEREO
group.
NR 12
TC 20
Z9 20
U1 0
U2 1
PU SPRINGER
PI DORDRECHT
PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS
SN 0038-0938
J9 SOL PHYS
JI Sol. Phys.
PD MAY
PY 2009
VL 256
IS 1-2
BP 365
EP 377
DI 10.1007/s11207-008-9304-7
PG 13
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 438OC
UT WOS:000265563900021
ER
PT J
AU Mason, GM
Desai, MI
Mall, U
Korth, A
Bucik, R
von Rosenvinge, TT
Simunac, KD
AF Mason, G. M.
Desai, M. I.
Mall, U.
Korth, A.
Bucik, R.
von Rosenvinge, T. T.
Simunac, K. D.
TI In situ Observations of CIRs on STEREO, Wind, and ACE During 2007-2008
SO SOLAR PHYSICS
LA English
DT Article
DE Acceleration of particles; Sun: abundances; Solar wind; Interplanetary
medium; Cosmic rays; Shock waves
ID COROTATING INTERACTION REGIONS; ENERGETIC PARTICLES; SOLAR-WIND;
ACCELERATION PROCESSES; HEAVY-IONS; HELIOSPHERE; SPACECRAFT; INJECTION;
AU; ENHANCEMENTS
AB During the 2007 and 2008 solar minimum period, STEREO, Wind, and ACE observed numerous Corotating Interaction Regions (CIRs) over spatial separations that began with all the spacecraft close to Earth, through STEREO separation angles of similar to aEuro parts per thousand 80 degrees in the fall of 2008. Over 35 CIR events were of sufficient intensity to allow measurement of He and heavy ion spectra using the IMPACT/SIT, EPACT/STEP and ACE/ULEIS instruments on STEREO, Wind, and ACE, respectively. In addition to differences between the spacecraft expected on the basis of simple corotation, we observed several events where there were markedly different time-intensity profiles from one spacecraft to the next. By comparing the energetic particle intensities and spectral shapes along with solar wind speed we examine the extent to which these differences are due to temporal evolution of the CIR or due to variations in connection to a relatively stable interaction region. Comparing CIRs in the 1996 -aEuro parts per thousand 1997 solar minimum period vs. 2007 -aEuro parts per thousand 2008, we find that the 2007 -aEuro parts per thousand 2008 period had many more CIRs, reflecting the presence of more high-speed solar wind streams, whereas 1997 had almost no CIR activity.
C1 [Mason, G. M.] Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA.
[Desai, M. I.] SW Res Inst, San Antonio, TX 78238 USA.
[Mall, U.; Korth, A.; Bucik, R.] Max Planck Inst Sonnensyst Forsch, D-37191 Katlenburg Lindau, Germany.
[von Rosenvinge, T. T.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
[Simunac, K. D.] Univ New Hampshire, Dept Phys, Durham, NH 03824 USA.
RP Mason, GM (reprint author), Johns Hopkins Univ, Appl Phys Lab, Johns Hopkins Rd, Laurel, MD 20723 USA.
EM glenn.mason@jhuapl.edu
RI Bucik, Radoslav/B-6501-2016
OI Bucik, Radoslav/0000-0001-7381-6949
FU NASA [NNX07AP69G]; University of California Berkeley [SA4889-26309];
Max-Planck-Gesellschaft zur Foerderung der Wissenschaften;
Bundesministerium fur Bildung und Forschung (BMBF) [50 OC 0501]
FX We thank the Wind/SWE team for solar wind speed data used here and the
ACE/MAG team for their list of transients and disturbances maintained on
the ACE Science Center web site. Figure 8 was produced using the Solar
Weather Browser, sponsored by the Royal Observatory of Belgium and ESA.
Sunspot numbers in Figure 10, and SEP event sizes in Figure 11 were
obtained from the NOAA ftp site. The work at the Johns Hopkins
University/Applied Physics Laboratory was supported by NASA under grant
NNX07AP69G and contract SA4889-26309 from the University of California
Berkeley. This work was also supported by the Max-Planck-Gesellschaft
zur Foerderung der Wissenschaften and the Bundesministerium fur Bildung
und Forschung (BMBF) under grant 50 OC 0501.
NR 31
TC 31
Z9 31
U1 0
U2 1
PU SPRINGER
PI DORDRECHT
PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS
SN 0038-0938
J9 SOL PHYS
JI Sol. Phys.
PD MAY
PY 2009
VL 256
IS 1-2
BP 393
EP 408
DI 10.1007/s11207-009-9367-0
PG 16
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 438OC
UT WOS:000265563900023
ER
PT J
AU von Rosenvinge, TT
Richardson, IG
Reames, DV
Cohen, CMS
Cummings, AC
Leske, RA
Mewaldt, RA
Stone, EC
Wiedenbeck, ME
AF von Rosenvinge, T. T.
Richardson, I. G.
Reames, D. V.
Cohen, C. M. S.
Cummings, A. C.
Leske, R. A.
Mewaldt, R. A.
Stone, E. C.
Wiedenbeck, M. E.
TI The Solar Energetic Particle Event of 14 December 2006
SO SOLAR PHYSICS
LA English
DT Article
DE Solar energetic particles; STEREO; Magnetic cloud
ID MAGNETIC CLOUDS; FLARE PARTICLES; ANISOTROPY; TOPOLOGY; SPACE; WIND;
FLUX
AB The solar energetic particle event on 14 December 2006 was observed by several near-Earth spacecraft including the Advanced Composition Explorer (ACE), STEREO A and B, SOHO and Wind. An interesting feature of this event is a series of unusual fluctuations in the particle intensity that occurred during the first few hours. These fluctuations were observed inside a magnetic cloud that originated in a solar event on 13 December and show both similarities and variations at the different spacecraft. Interestingly, the most striking difference is between observations at the two closely-separated STEREO spacecraft. In particular, large fluctuations in the proton intensity were seen by the High Energy Telescope (HET) on STEREO A, and to a lesser extent at Wind and ACE, but not by the STEREO B HET. We conclude that the differences in intensity-time profiles were caused by anisotropies in the particle distribution and the different viewing directions of the individual particle telescopes. The intensity/anisotropy variations suggest that flux tubes with different particle propagation conditions existed within this magnetic cloud despite the absence of local magnetic field signatures associated with these regions. The intensity fluctuations are similar to those occasionally seen in impulsive particle events. There were also spacecraft-to-spacecraft differences during the onset of the particle event. An initial rapid onset of energetic (> 40 MeV) protons was observed by the STEREO A and B spacecraft outside the magnetic cloud, but not by spacecraft such as SOHO that were already inside the magnetic cloud at this time. The latter spacecraft observed a slower, lower intensity increase. Evidently, energetic proton propagation from the solar event to the vicinity of Earth was inhibited within the magnetic cloud compared to outside.
C1 [von Rosenvinge, T. T.; Richardson, I. G.; Reames, D. V.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
[Cohen, C. M. S.; Cummings, A. C.; Leske, R. A.; Mewaldt, R. A.; Stone, E. C.] CALTECH, Pasadena, CA 91125 USA.
[Wiedenbeck, M. E.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
[Richardson, I. G.] Univ Maryland, Dept Astron, College Pk, MD 20742 USA.
[Richardson, I. G.] Univ Maryland, CRESST, College Pk, MD 20742 USA.
RP von Rosenvinge, TT (reprint author), NASA, Goddard Space Flight Ctr, Code 661, Greenbelt, MD 20771 USA.
EM tycho.t.vonrosenvinge@nasa.gov; ian.g.richardson@nasa.gov;
Donald.V.Reames@nasa.gov; cohen@srl.caltech.edu; ace@srl.caltech.edu;
ral@srl.caltech.edu; rmewaldt@srl.caltech.edu; ecs@srl.caltech.edu;
mark.e.wiedenbeck@jpl.nasa.gov
OI Richardson, Ian/0000-0002-3855-3634
FU NASA [SA2715-26309, NAS5-03131]; University of California, Berkeley
FX We thank Janet Luhmann of the University of California, Berkeley, for
her steadfast support as the Principal Investigator of the STEREO/IMPACT
investigation. The work at GSFC, Caltech and JPL was supported by NASA
(Caltech and JPL were funded under subcontract SA2715-26309 from the
University of California, Berkeley, under NASA Contract NAS5-03131). The
ACE observations used in this paper are from the ACE Science Center
(http://www.srl.caltech.edu/ACE/ASC/), and the STEREO magnetic fields
were obtained from the STEREO archive at UCLA
(http://www-ssc.igpp.ucla.edu/forms/stereo/). The SOHO/ERNE data were
obtained from the Space Research Laboratory, University of Turku
(http://www.srl.utu.fi/erne_data/).
NR 21
TC 17
Z9 17
U1 1
U2 1
PU SPRINGER
PI DORDRECHT
PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS
SN 0038-0938
J9 SOL PHYS
JI Sol. Phys.
PD MAY
PY 2009
VL 256
IS 1-2
BP 443
EP 462
DI 10.1007/s11207-009-9353-6
PG 20
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 438OC
UT WOS:000265563900026
ER
PT J
AU Meyer-Vernet, N
Maksimovic, M
Czechowski, A
Mann, I
Zouganelis, I
Goetz, K
Kaiser, ML
St Cyr, OC
Bougeret, JL
Bale, SD
AF Meyer-Vernet, N.
Maksimovic, M.
Czechowski, A.
Mann, I.
Zouganelis, I.
Goetz, K.
Kaiser, M. L.
St Cyr, O. C.
Bougeret, J. -L.
Bale, S. D.
TI Dust Detection by the Wave Instrument on STEREO: Nanoparticles Picked up
by the Solar Wind?
SO SOLAR PHYSICS
LA English
DT Article
DE Plasma physics; Solar wind; Waves, plasma
ID ION FORMATION; IMPACT; SPACECRAFT; PARTICLES; STREAMS; GRAINS; ORIGIN;
SATURN; SYSTEM; RADIO
AB The STEREO wave instrument (S/WAVES) has detected a very large number of intense voltage pulses. We suggest that these events are produced by impact ionisation of nanoparticles striking the spacecraft at a velocity of the order of magnitude of the solar wind speed. Nanoparticles, which are half-way between micron-sized dust and atomic ions, have such a large charge-to-mass ratio that the electric field induced by the solar wind magnetic field accelerates them very efficiently. Since the voltage produced by dust impacts increases very fast with speed, such nanoparticles produce signals as high as do much larger grains of smaller speeds. The flux of 10-nm radius grains inferred in this way is compatible with the interplanetary dust flux model. The present results may represent the first detection of fast nanoparticles in interplanetary space near Earth orbit.
C1 [Meyer-Vernet, N.; Maksimovic, M.; Zouganelis, I.; Bougeret, J. -L.] Univ Paris Diderot, Observ Paris, CNRS, UPMC,LESIA, F-92190 Meudon, France.
[Zouganelis, I.] UPMC, CNRS, LPP, Ecole Polytech, F-94107 St Maur Des Fosses, France.
[Czechowski, A.] Polish Acad Sci, Space Res Ctr, PL-00716 Warsaw, Poland.
[Mann, I.] Kindai Univ, Sch Sci & Engn, Osaka 5778502, Japan.
[Goetz, K.] Univ Minnesota, Sch Phys & Astron, Minneapolis, MN 55455 USA.
[Kaiser, M. L.; St Cyr, O. C.] NASA, GSFC, Greenbelt, MD 20771 USA.
[Bale, S. D.] Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA.
RP Meyer-Vernet, N (reprint author), Univ Paris Diderot, Observ Paris, CNRS, UPMC,LESIA, 5 Pl Jules Janssen, F-92190 Meudon, France.
EM nicole.meyer@obspm.fr; ace@cbk.waw.pl; mann@kindai.ac.jp;
yannis.zouganelis@lpp.polytechnique.fr; goetz@waves.space.umn.edu;
michael.kaiser@nasa.gov; bale@ssl.berkeley.edu
RI Bale, Stuart/E-7533-2011
OI Bale, Stuart/0000-0002-1989-3596
FU CNES; CNRS; Polish Ministry of Science [4 T12E 002 30]
FX We thank the team who conceived, designed, built, and tested the S/WAVES
instrument, and are very grateful to P.-L. Astier for simulations of the
response to transient pulses. The French part was supported by CNES and
CNRS. A. C. was supported by the Polish Ministry of Science grant 4 T12E
002 30. We thank the International Space Science Institute for fostering
discussions within the working group 'Dust-plasma interactions:
observations in the interplanetary medium and in the environment of
solar system objects'. We are grateful to an anonymous referee for
helpful comments.
NR 33
TC 66
Z9 66
U1 0
U2 7
PU SPRINGER
PI DORDRECHT
PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS
SN 0038-0938
J9 SOL PHYS
JI Sol. Phys.
PD MAY
PY 2009
VL 256
IS 1-2
BP 463
EP 474
DI 10.1007/s11207-009-9349-2
PG 12
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 438OC
UT WOS:000265563900027
ER
PT J
AU St Cyr, OC
Kaiser, ML
Meyer-Vernet, N
Howard, RA
Harrison, RA
Bale, SD
Thompson, WT
Goetz, K
Maksimovic, M
Bougeret, JL
Wang, D
Crothers, S
AF St Cyr, O. C.
Kaiser, M. L.
Meyer-Vernet, N.
Howard, R. A.
Harrison, R. A.
Bale, S. D.
Thompson, W. T.
Goetz, K.
Maksimovic, M.
Bougeret, J. -L.
Wang, D.
Crothers, S.
TI STEREO SECCHI and S/WAVES Observations of Spacecraft Debris Caused by
Micron-Size Interplanetary Dust Impacts
SO SOLAR PHYSICS
LA English
DT Article
ID MISSION; LASCO
AB Early in the STEREO mission observers noted that the white-light instruments of the SECCHI suite were detecting significantly more spacecraft-related "debris" than any previously flown coronagraphic instruments. Comparison of SECCHI "debris storms" with S/WAVES indicates that almost all are coincident with the most intense transient emissions observed by the radio and plasma waves instrument. We believe the debris is endogenous (i.e., from the spacecraft thermal blanketing), and the storms appear to be caused by impacts of large interplanetary dust grains that are detected by S/WAVES. Here we report the observations, compare them to interplanetary dust distributions, and document a reminder for future spacebased coronagraphic instrument builders.
C1 [St Cyr, O. C.; Kaiser, M. L.; Thompson, W. T.] NASA, Goddard Space Flight Ctr, Greenbelt, MD USA.
[Meyer-Vernet, N.; Maksimovic, M.; Bougeret, J. -L.] Univ Paris Diderot, Observ Paris, UPMC, LESIA,CNRS, F-92190 Meudon, France.
[Howard, R. A.; Wang, D.] Naval Res Lab, Washington, DC USA.
[Harrison, R. A.; Crothers, S.] Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England.
[Bale, S. D.] Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA.
[Thompson, W. T.] Adnet Syst Inc, Rockville, MD USA.
[Goetz, K.] Univ Minnesota, Sch Phys & Astron, Minneapolis, MN 55455 USA.
[Wang, D.] Interferometrics, Herndon, VA USA.
[Bale, S. D.] Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA.
RP St Cyr, OC (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD USA.
EM chris.stcyr@nasa.gov
RI Bale, Stuart/E-7533-2011; Thompson, William/D-7376-2012
OI Bale, Stuart/0000-0002-1989-3596;
FU NASA; Particle Physics and Astronomy Research Council; Deutsches Zentrum
fur Luft- und Raumfahrt e.V.; Belgian Science Policy Office; Centre
National d'Etudes Spatiales; Centre National de la Recherche
Scientifique; USAF Space Test Program; Office of Naval Research; CNRS
FX The SECCHI data used here are produced by an international consortium of
the Naval Research Laboratory, Lockheed Martin Solar and Astrophysics
Laboratory, and NASA Goddard Space Flight Center (USA), Rutherford
Appleton Laboratory and University of Birmingham (UK),
Max-Planck-Institut fur Sonnensystemforschung (Germany), Centre Spatiale
de Liege (Belgium), Institut d'Optique Theorique et Appliquee, and
Institut d'Astrophysique Spatiale (France). The USA institutions were
funded by NASA; the UK institutions by Particle Physics and Astronomy
Research Council; the German institutions by Deutsches Zentrum fur Luft-
und Raumfahrt e. V.; the Belgian institutions by Belgian Science Policy
Office; the French institutions by Centre National d'Etudes Spatiales
and the Centre National de la Recherche Scientifique. The NRL effort was
also supported by the USAF Space Test Program and the Office of Naval
Research. The S/WAVES data used here are produced by an international
consortium of the Observatoire de Paris (France), the University of
Minnesota (USA), the University of California Berkeley (USA), and NASA
Goddard Space Flight Center (USA). The French contribution was funded by
CNRS, and the USA institutions were funded by NASA. We also gratefully
acknowledge contributions from K. Baldwin (NRL), J.-P. Olive (ESA), A.
Dreisman (JHU/APL), and C. Edgerton (Edge Space Systems).
NR 18
TC 12
Z9 12
U1 0
U2 2
PU SPRINGER
PI DORDRECHT
PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS
SN 0038-0938
J9 SOL PHYS
JI Sol. Phys.
PD MAY
PY 2009
VL 256
IS 1-2
BP 475
EP 488
DI 10.1007/s11207-009-9362-5
PG 14
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 438OC
UT WOS:000265563900028
ER
PT J
AU De Keyser, J
Carpenter, DL
Darrouzet, F
Gallagher, DL
Tu, JN
AF De Keyser, Johan
Carpenter, Donald L.
Darrouzet, Fabien
Gallagher, Dennis L.
Tu, Jiannan
TI CLUSTER and IMAGE: New Ways to Study the Earth's Plasmasphere
SO SPACE SCIENCE REVIEWS
LA English
DT Review
DE Plasmasphere; CLUSTER; IMAGE; Measurement techniques
ID ELECTROMAGNETIC-WAVE FIELD; ELECTRON-DENSITY PROFILES; NONTHERMAL
CONTINUUM; MAGNETIC-FIELD; INNER MAGNETOSPHERE; 6-COMPONENT
MEASUREMENTS; POTENTIAL MEASUREMENTS; MAGNETOPAUSE CURRENT; GRADIENT
CALCULATION; PLASMAPAUSE REGION
AB Ground-based instruments and a number of space missions have contributed to our knowledge of the plasmasphere since its discovery half a century ago, but it is fair to say that many questions have remained unanswered. Recently, NASA's Image and ESA's Cluster probes have introduced new observational concepts, thereby providing a non-local view of the plasmasphere. Image carried an extreme ultraviolet imager producing global pictures of the plasmasphere. Its instrumentation also included a radio sounder for remotely sensing the spacecraft environment. The Cluster mission provides observations at four nearby points as the four-spacecraft configuration crosses the outer plasmasphere on every perigee pass, thereby giving an idea of field and plasma gradients and of electric current density. This paper starts with a historical overview of classical single-spacecraft data interpretation, discusses the non-local nature of the Image and Cluster measurements, and emphasizes the importance of the new data interpretation tools that have been developed to extract non-local information from these observations. The paper reviews these innovative techniques and highlights some of them to give an idea of the flavor of these methods. In doing so, it is shown how the non-local perspective opens new avenues for plasmaspheric research.
C1 [De Keyser, Johan; Darrouzet, Fabien] Belgian Inst Space Aeron, B-1180 Brussels, Belgium.
[Carpenter, Donald L.] Stanford Univ, Space Telecommun & Radiosci Lab, Stanford, CA 94305 USA.
[Gallagher, Dennis L.] NASA, George C Marshall Space Flight Ctr, Natl Space Sci & Technol Ctr, Huntsville, AL 35812 USA.
[Tu, Jiannan] Univ Massachusetts, Ctr Atmospher Res, Lowell, MA USA.
RP De Keyser, J (reprint author), Belgian Inst Space Aeron, Ringlaan 3, B-1180 Brussels, Belgium.
EM Johan.DeKeyser@aeronomie.be; dlc@nova.stanford.edu;
Fabien.Darrouzet@aeronomie.be; dennis.l.gallagher@nasa.gov;
Jiannan_Tu@uml.edu
NR 192
TC 2
Z9 2
U1 0
U2 2
PU SPRINGER
PI DORDRECHT
PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS
SN 0038-6308
J9 SPACE SCI REV
JI Space Sci. Rev.
PD MAY
PY 2009
VL 145
IS 1-2
BP 7
EP 53
DI 10.1007/s11214-008-9464-7
PG 47
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 457FT
UT WOS:000266914600003
ER
PT J
AU Darrouzet, F
Gallagher, DL
Andre, N
Carpenter, DL
Dandouras, I
Decreau, PME
De Keyser, J
Denton, RE
Foster, JC
Goldstein, J
Moldwin, MB
Reinisch, BW
Sandel, BR
Tu, JN
AF Darrouzet, Fabien
Gallagher, Dennis L.
Andre, Nicolas
Carpenter, Donald L.
Dandouras, Iannis
Decreau, Pierrette M. E.
De Keyser, Johan
Denton, Richard E.
Foster, John C.
Goldstein, Jerry
Moldwin, Mark B.
Reinisch, Bodo W.
Sandel, Bill R.
Tu, Jiannan
TI Plasmaspheric Density Structures and Dynamics: Properties Observed by
the CLUSTER and IMAGE Missions
SO SPACE SCIENCE REVIEWS
LA English
DT Review
DE Plasmasphere; CLUSTER; IMAGE; Plasma Structures
ID EXTREME-ULTRAVIOLET IMAGER; RADIO PLASMA IMAGER; FIELD-ALIGNED
IRREGULARITIES; ELECTRON-DENSITY; OUTER PLASMASPHERE; WHISTLER EVIDENCE;
PROPAGATION CHARACTERISTICS; EARTHS MAGNETOSPHERE; MAGNETIC STORMS;
TOPSIDE-SOUNDER
AB Plasmaspheric density structures have been studied since the discovery of the plasmasphere in the late 1950s. But the advent of the Cluster and Image missions in 2000 has added substantially to our knowledge of density structures, thanks to the new capabilities of those missions: global imaging with Image and four-point in situ measurements with Cluster. The study of plasma sources and losses has given new results on refilling rates and erosion processes. Two-dimensional density images of the plasmasphere have been obtained. The spatial gradient of plasmaspheric density has been computed. The ratios between H+, He+ and O+ have been deduced from different ion measurements. Plasmaspheric plumes have been studied in detail with new tools, which provide information on their morphology, dynamics and occurrence. Density structures at smaller scales have been revealed with those missions, structures that could not be clearly distinguished before the global images from Image and the four-point measurements by Cluster became available. New terms have been given to these structures, like "shoulders", "channels", "fingers" and "crenulations". This paper reviews the most relevant new results about the plasmaspheric plasma obtained since the start of the Cluster and Image missions.
C1 [Darrouzet, Fabien; De Keyser, Johan] Belgian Inst Space Aeron IASB BIRA, B-1180 Brussels, Belgium.
[Gallagher, Dennis L.] NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA.
[Andre, Nicolas] ESA, RSSD, Noordwijk, Netherlands.
[Carpenter, Donald L.] Stanford Univ, Space Telecommun & Radiosci Lab, Stanford, CA 94305 USA.
[Dandouras, Iannis] Univ Toulouse, CNRS, CESR, Toulouse, France.
[Decreau, Pierrette M. E.] Univ Orleans, CNRS, LPCE, Orleans, France.
[Denton, Richard E.] Dartmouth Coll, Dept Phys & Astron, Hanover, NH 03755 USA.
[Foster, John C.] MIT, Haystack Observ, Westford, MA 01886 USA.
[Goldstein, Jerry] SW Res Inst, San Antonio, TX USA.
[Moldwin, Mark B.] Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90024 USA.
[Reinisch, Bodo W.; Tu, Jiannan] UML, Ctr Atmospher Res, Lowell, MA USA.
[Sandel, Bill R.] Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA.
RP Darrouzet, F (reprint author), Belgian Inst Space Aeron IASB BIRA, 3 Ave Circulaire, B-1180 Brussels, Belgium.
EM Fabien.Darrouzet@oma.be; dennis.l.gallagher@nasa.gov;
nandre@rssd.esa.int; dlc@nova.stanford.edu; Iannis.Dandouras@cesr.fr;
Pierrette.Decreau@cnrs-orleans.fr; Johan.DeKeyser@oma.be;
richard.e.denton@dartmouth.edu; jfoster@haystack.mit.edu;
jgoldstein@swri.edu; mmoldwin@igpp.ucla.edu; Bodo_Reinisch@uml.edu;
sandel@arizona.edu; Jiannan_Tu@uml.edu
RI Moldwin, Mark/F-8785-2011;
OI Moldwin, Mark/0000-0003-0954-1770; Dandouras,
Iannis/0000-0002-7121-1118; Darrouzet, Fabien/0000-0002-2927-6858
NR 155
TC 58
Z9 58
U1 2
U2 11
PU SPRINGER
PI DORDRECHT
PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS
SN 0038-6308
EI 1572-9672
J9 SPACE SCI REV
JI Space Sci. Rev.
PD MAY
PY 2009
VL 145
IS 1-2
BP 55
EP 106
DI 10.1007/s11214-008-9438-9
PG 52
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 457FT
UT WOS:000266914600004
ER
PT J
AU Matsui, H
Foster, JC
Carpenter, DL
Dandouras, I
Darrouzet, F
De Keyser, J
Gallagher, DL
Goldstein, J
Puhl-Quinn, PA
Vallat, C
AF Matsui, Hiroshi
Foster, John C.
Carpenter, Donald L.
Dandouras, Iannis
Darrouzet, Fabien
De Keyser, Johan
Gallagher, Dennis L.
Goldstein, Jerry
Puhl-Quinn, Pamela A.
Vallat, Claire
TI Electric Fields and Magnetic Fields in the Plasmasphere: A Perspective
From CLUSTER and IMAGE
SO SPACE SCIENCE REVIEWS
LA English
DT Review
DE Plasmasphere; Electric Field; Magnetic Field; CLUSTER; IMAGE
ID SUBAURORAL ION DRIFTS; EDI CONVECTION MEASUREMENTS; WHISTLER MODE
SIGNALS; MAGNETOSPHERIC CONVECTION; IONOSPHERIC CONVECTION; INNER
MAGNETOSPHERE; RING CURRENT; SOLAR-WIND; POLARIZATION STREAM; OUTER
PLASMASPHERE
AB The electric field and magnetic field are basic quantities in the plasmasphere measured since the 1960s. In this review, we first recall conventional wisdom and remaining problems from ground-based whistler measurements. Then we show scientific results from Cluster and Image, which are specifically made possible by newly introduced features on these spacecraft, as follows. 1. In situ electric field measurements using artificial electron beams are successfully used to identify electric fields originating from various sources. 2. Global electric fields are derived from sequences of plasmaspheric images, revealing how the inner magnetospheric electric field responds to the southward interplanetary magnetic fields and storms/substorms. 3. Understanding of sub-auroral polarization stream (SAPS) or sub-auroral ion drifts (SAID) are advanced through analysis of a combination of magnetospheric and ionospheric measurements from Cluster, Image, and DMSP. 4. Data from multiple spacecraft have been used to estimate magnetic gradients for the first time.
C1 [Matsui, Hiroshi; Puhl-Quinn, Pamela A.] Univ New Hampshire, Ctr Space Sci, Durham, NH 03824 USA.
[Foster, John C.] MIT, Westford, MA USA.
[Carpenter, Donald L.] Stanford Univ, Space Telecommun & Radiosci Lab, Stanford, CA 94305 USA.
[Dandouras, Iannis] CESR, Toulouse, France.
[Darrouzet, Fabien; De Keyser, Johan] Belgian Inst Space Aeron BIRA IASB, Brussels, Belgium.
[Gallagher, Dennis L.] NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA.
[Goldstein, Jerry] SW Res Inst, San Antonio, TX USA.
[Vallat, Claire] ESA, Villafranca, Spain.
RP Matsui, H (reprint author), Univ New Hampshire, Ctr Space Sci, Morse Hall,39 Coll Rd, Durham, NH 03824 USA.
EM hiroshi.matsui@unh.edu; jfoster@haystack.mit.edu; dlc@nova.stanford.edu;
Iannis.Dandouras@cesr.fr; Fabien.Darrouzet@oma.be;
Johan.DeKeyser@oma.be; dennis.l.gallagher@nasa.gov; jgoldstein@swri.edu;
pamela.puhlquinn@unh.edu; Claire.Vallat@sciops.esa.int
OI Dandouras, Iannis/0000-0002-7121-1118
FU NASA [NNG05GG50G, NNX07AI03G]; Belgian Federal Science Policy Office
(BELSPO) [13127/98/NL/VJ]
FX H. Matsui and P. A. Puhl- Quinn acknowledge the support by NASA through
grants NNG05GG50G and NNX07AI03G. J. De Keyser and F. Darrouzet
acknowledge the support by the Belgian Federal Science Policy Office
(BELSPO) through the ESA/PRODEX CLUSTER project (contract 13127/98/NL/VJ
(IC)). This paper is an outcome of the workshop " The Earth's
plasmasphere: A CLUSTER, IMAGE, and modeling perspective", organized by
the Belgian Institute for Space Aeronomy in Brussels in September 2007.
NR 110
TC 2
Z9 2
U1 0
U2 2
PU SPRINGER
PI DORDRECHT
PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS
SN 0038-6308
EI 1572-9672
J9 SPACE SCI REV
JI Space Sci. Rev.
PD MAY
PY 2009
VL 145
IS 1-2
BP 107
EP 135
DI 10.1007/s11214-008-9471-8
PG 29
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 457FT
UT WOS:000266914600005
ER
PT J
AU Masson, A
Santolik, O
Carpenter, DL
Darrouzet, F
Decreau, PME
Mazouz, FE
Green, JL
Grimald, S
Moldwin, MB
Nemec, F
Sonwalkar, VS
AF Masson, Arnaud
Santolik, Ondrej
Carpenter, Donald L.
Darrouzet, Fabien
Decreau, Pierrette M. E.
Mazouz, Farida El-Lemdani
Green, James L.
Grimald, Sandrine
Moldwin, Mark B.
Nemec, Frantisek
Sonwalkar, Vikas S.
TI Advances in Plasmaspheric Wave Research with CLUSTER and IMAGE
Observations
SO SPACE SCIENCE REVIEWS
LA English
DT Review
DE Plasmasphere; CLUSTER; IMAGE; Waves
ID FIELD LINE RESONANCES; RADIO PLASMA IMAGER; STORM-TIME CHORUS;
NONTHERMAL CONTINUUM RADIATION; PROTON CYCLOTRON ECHOES; WHISTLER-MODE
CHORUS; EQUATORIAL NOISE; ELECTRON-DENSITY; LOW-LATITUDE; VLF HISS
AB This paper highlights significant advances in plasmaspheric wave research with Cluster and Image observations. This leap forward was made possible thanks to the new observational capabilities of these space missions. On one hand, the multipoint view of the four Cluster satellites, a unique capability, has enabled the estimation of wave characteristics impossible to derive from single spacecraft measurements. On the other hand, the Image experiments have enabled to relate large-scale plasmaspheric density structures with wave observations and provide radio soundings of the plasmasphere with unprecedented details. After a brief introduction on Cluster and Image wave instrumentation, a series of sections, each dedicated to a specific type of plasmaspheric wave, put into context the recent advances obtained by these two revolutionary missions.
C1 [Masson, Arnaud] ESA ESTEC, Sci Operat Dept, NL-2201 AZ Noordwijk, Netherlands.
[Santolik, Ondrej; Nemec, Frantisek] Charles Univ Prague, Fac Math & Phys, Inst Atmospher Phys, Prague, Czech Republic.
[Carpenter, Donald L.] Stanford Univ, Space Telecommun & Radiosci Lab, Stanford, CA 94305 USA.
[Darrouzet, Fabien] Belgian Inst Space Aeron BIRA IASB, Brussels, Belgium.
[Decreau, Pierrette M. E.; Mazouz, Farida El-Lemdani] Univ Orleans, CNRS, LPC2E, Orleans, France.
[Green, James L.] NASA Headquarters, Washington, DC USA.
[Grimald, Sandrine] Univ Coll London, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England.
[Moldwin, Mark B.] Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90024 USA.
[Sonwalkar, Vikas S.] Univ Alaska Fairbanks, Dept Elect & Comp Engn, Fairbanks, AK USA.
RP Masson, A (reprint author), ESA ESTEC, Sci Operat Dept, Keplerlaan 1, NL-2201 AZ Noordwijk, Netherlands.
EM Arnaud.Masson@esa.int; ondrej.santolik@mff.cuni.cz;
dlc@nova.stanford.edu; Fabien.Darrouzet@oma.be;
Pierrette.Decreau@cnrs-orleans.fr; mazouz@cnrs-orleans.fr;
James.L.Green@nasa.gov; sg2@mssl.ucl.ac.uk; mmoldwin@igpp.ucla.edu;
frantisek.nemec@mff.cuni.cz; ffvss@uaf.edu
RI Moldwin, Mark/F-8785-2011; Nemec, Frantisek/H-7027-2013; Santolik,
Ondrej/F-7766-2014
OI Moldwin, Mark/0000-0003-0954-1770; Nemec, Frantisek/0000-0002-3233-2718;
NR 154
TC 7
Z9 7
U1 0
U2 5
PU SPRINGER
PI DORDRECHT
PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS
SN 0038-6308
EI 1572-9672
J9 SPACE SCI REV
JI Space Sci. Rev.
PD MAY
PY 2009
VL 145
IS 1-2
BP 137
EP 191
DI 10.1007/s11214-009-9508-7
PG 55
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 457FT
UT WOS:000266914600006
ER
PT J
AU Reinisch, BW
Moldwin, MB
Denton, RE
Gallagher, DL
Matsui, H
Pierrard, V
Tu, JN
AF Reinisch, Bodo W.
Moldwin, Mark B.
Denton, Richard E.
Gallagher, Dennis L.
Matsui, Hiroshi
Pierrard, Viviane
Tu, Jiannan
TI Augmented Empirical Models of Plasmaspheric Density and Electric Field
Using IMAGE and CLUSTER Data
SO SPACE SCIENCE REVIEWS
LA English
DT Review
DE Inner magnetosphere; Plasmasphere; Empirical models; Plasma density;
Electric field; CLUSTER; IMAGE
ID INTERPLANETARY MAGNETIC-FIELD; HIGH-LATITUDE IONOSPHERE; PLASMA-MASS
DENSITY; MAGNETOSPHERIC CONVECTION; INNER MAGNETOSPHERE; RING CURRENT;
ULF WAVES; EARTHS MAGNETOSPHERE; TEMPORAL VARIATIONS; TOPSIDE IONOSPHERE
AB Empirical models for the plasma densities in the inner magnetosphere, including plasmasphere and polar magnetosphere, have been in the past derived from in situ measurements. Such empirical models, however, are still in their initial phase compared to magnetospheric magnetic field models. Recent studies using data from CRRES, Polar, and Image have significantly improved empirical models for inner-magnetospheric plasma and mass densities. Comprehensive electric field models in the magnetosphere have been developed using radar and in situ observations at low altitude orbits. To use these models at high altitudes one needs to rely strongly on the assumption of equipotential magnetic field lines. Direct measurements of the electric field by the Cluster mission have been used to derive an equatorial electric field model in which reliance on the equipotential assumption is less. In this paper we review the recent progress in developing empirical models of plasma densities and electric fields in the inner magnetosphere with emphasis on the achievements from the Image and Cluster missions. Recent results from other satellites are also discussed when they are relevant.
C1 [Reinisch, Bodo W.; Tu, Jiannan] Univ Massachusetts, Dept Environm Earth & Atmospher Sci, Lowell, MA 01854 USA.
[Moldwin, Mark B.] Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90024 USA.
[Denton, Richard E.] Dartmouth Coll, Dept Phys & Astron, Hanover, NH 03755 USA.
[Gallagher, Dennis L.] NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA.
[Matsui, Hiroshi] Univ New Hampshire, Ctr Space Sci, Durham, NH 03824 USA.
[Pierrard, Viviane] Belgian Inst Space Aeron BIRA IASB, Brussels, Belgium.
RP Reinisch, BW (reprint author), Univ Massachusetts, Dept Environm Earth & Atmospher Sci, 600 Suffolk St, Lowell, MA 01854 USA.
EM bodo_reinisch@uml.edu; mmoldwin@igpp.ucla.edu;
richard.e.denton@dartmouth.edu; dennis.l.gallagher@nasa.gov;
hiroshi.matsui@unh.edu; viviane.pierrard@oma.be; jiannan_tu@uml.edu
RI Moldwin, Mark/F-8785-2011;
OI Moldwin, Mark/0000-0003-0954-1770; Pierrard, Viviane/0000-0001-5014-7682
FU NASA [NNX07AG38G]; SwRI [83822]; NSF [0518227, ATM-0632740,
ATM-0120950]; AFRL [FA8718-06-C-0072]
FX The work at UML was supported by NASA grant NNX07AG38G, NASA grant via
subcontract 83822 from SwRI, NSF grant 0518227, and AFRL contract
FA8718-06-C-0072 to the University of Massachusetts Lowell. The work at
Dartmouth College was supported by NSF grants ATM-0632740 and
ATM-0120950 (Center for Integrated Space Weather Modeling, CISM, funded
by the Science and Technology Centers Program). This paper is an outcome
of the workshop " The Earth's plasmasphere: A CLUSTER, IMAGE, and
modeling perspective", organized by the Belgian Institute for Space
Aeronomy in Brussels in September 2007. The use of Figs. 2, 3, 5 and 6
is with the permission of Elsevier.
NR 135
TC 22
Z9 23
U1 0
U2 4
PU SPRINGER
PI DORDRECHT
PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS
SN 0038-6308
EI 1572-9672
J9 SPACE SCI REV
JI Space Sci. Rev.
PD MAY
PY 2009
VL 145
IS 1-2
BP 231
EP 261
DI 10.1007/s11214-008-9481-6
PG 31
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 457FT
UT WOS:000266914600008
ER
PT J
AU Hasan, AR
Kabir, CS
Wang, X
AF Hasan, A. R.
Kabir, C. S.
Wang, X.
TI A Robust Steady-State Model for Flowing-Fluid Temperature in Complex
Wells
SO SPE PRODUCTION & OPERATIONS
LA English
DT Article
ID 2-PHASE FLOW; WELLBORE/RESERVOIR SIMULATOR; HEAT-TRANSFER
AB This paper presents an analytic model for computing the wellbore-fluid-temperature profile for steady fluid flow. Although wells with a constant-deviation angle can be handled with existing analytic models, complex well architectures demand rigorous treatment. For example, changing geothermal-temperature-gradient and deepwater wells present significant challenges. Additionally, available analytic models rarely provide calculation methods for various required thermal parameters, such as the Joule-Thompson (J-T) coefficient and fluid expansivity.
The approach taken in this study entails dividing the wellbore into many sections of uniform thermal properties and deviation angle. The governing differential equation is solved for each section. with fluid temperature from the prior section as the boundary condition. This piecewise approach makes the model versatile, allowing step-by-step calculation of fluid temperature for the entire wellbore. We present simple, thermodynamically sound approaches for estimating thermal parameters.
Success is indicated when performance of the proposed model is compared with data from three wells, producing two-phase gas/oil mixture, single-phase oil, and single-phase gas. Sensitivity of the estimated fluid temperatures to various thermal properties is also examined with our model. Overall, the effects of the J-T coefficient and liquid expansivity are found to be significant.
C1 [Hasan, A. R.] Univ Minnesota, Duluth, MN 55812 USA.
[Hasan, A. R.] NASA, Washington, DC USA.
[Kabir, C. S.] Hess, Houston, TX USA.
RP Hasan, AR (reprint author), Univ Minnesota, Duluth, MN 55812 USA.
EM rhasan@d.umn.edu; skabir@hess.com; shawn.wang@bakerhughes.com
OI Kabir, Shah/0000-0002-1421-5761
NR 20
TC 18
Z9 21
U1 0
U2 5
PU SOC PETROLEUM ENG
PI RICHARDSON
PA 222 PALISADES CREEK DR,, RICHARDSON, TX 75080 USA
SN 1930-1855
J9 SPE PROD OPER
JI SPE Prod. Oper.
PD MAY
PY 2009
VL 24
IS 2
BP 269
EP 276
PG 8
WC Engineering, Petroleum
SC Engineering
GA 447IN
UT WOS:000266184900005
ER
PT J
AU Molod, A
AF Molod, Andrea
TI Running GCM physics and dynamics on different grids: algorithm and tests
SO TELLUS SERIES A-DYNAMIC METEOROLOGY AND OCEANOGRAPHY
LA English
DT Article
ID GENERAL-CIRCULATION MODEL; VERTICAL RESOLUTION; OCEAN; REPRESENTATION;
CONVECTION; SCALE
AB An 'alternate grid' (GridAlt) technique is presented, which allows the different components of a general circulation model's governing equations to be computed on distinct grids chosen for that component or process. In the implementation presented here, the tendencies of state variables from the physical parametrizations are computed on a vertical grid with very fine resolution near the surface, whereas the remaining terms in the equations of motion are computed using an Eta coordinate with coarser vertical resolution.
Results from a suite of aquaplanet experiments show that much of the benefit of increased vertical resolution in the whole model can be realized by enhancing the vertical resolution of the 'physics grid' using GridAlt. The benefit is realized in the fields which are computed directly in the physical parametrizations, and in the vertical structure of the relative humidity and mass streamfunction. Results from a suite of realistically configured simulations demonstrated an impact of GridAlt that was similar to its impact in the simplified simulations, as well as an improved response to El Nino Southern Oscillation forcing. It is concluded that the present implementation of GridAlt offers a practical way to allow GCMs to better capture the near-surface structure of the atmosphere.
C1 [Molod, Andrea] Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA.
[Molod, Andrea] NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Greenbelt, MD 20771 USA.
RP Molod, A (reprint author), Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA.
EM Andrea.Molod@nasa.gov
FU Climate Modeling Initiative (CMI); Alliance for Computational Earth
Sciences (ACES)
FX The author wishes to thank Jean-Michel Campin for all the helpful
consultations during the development of this work. In addition, the
author thanks Chris Hill and Joe Tribbia for their insights and comments
about the work and the manuscript. This work was supported under the
Climate Modeling Initiative (CMI), and the computations were funded
under the Alliance for Computational Earth Sciences (ACES).
NR 22
TC 2
Z9 2
U1 0
U2 1
PU WILEY-BLACKWELL PUBLISHING, INC
PI MALDEN
PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA
SN 0280-6495
J9 TELLUS A
JI Tellus Ser. A-Dyn. Meteorol. Oceanol.
PD MAY
PY 2009
VL 61
IS 3
BP 381
EP 393
DI 10.1111/j.1600-0870.2009.00394.x
PG 13
WC Meteorology & Atmospheric Sciences; Oceanography
SC Meteorology & Atmospheric Sciences; Oceanography
GA 427ZZ
UT WOS:000264818900005
ER
PT J
AU Johnson, DR
Perry, HM
Lyczkowski-Shultz, J
Hanisko, D
AF Johnson, Donald R.
Perry, Harriet M.
Lyczkowski-Shultz, Joanne
Hanisko, David
TI Red Snapper Larval Transport in the Northern Gulf of Mexico
SO TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY
LA English
DT Article
ID WEST FLORIDA SHELF; LUTJANUS-CAMPECHANUS; CONTINENTAL-SHELF;
MITOCHONDRIAL-DNA; CIRCULATION; MOVEMENT; HABITAT; PLUME
AB This study examines the advection of red snapper Lutjanus campechanus larvae in the northern Gulf of Mexico. The potential for repopulating the eastern Gulf stock through larval transport from the more populous western stock is addressed. Transport pathways across topographic features that inhibit alongshelf flow (e.g., the Mississippi River delta. DeSoto Canyon, and the Apalachicola peninsula) and interregional larval transport are considered. An advective field of currents is developed front a large database of drifter and moored Currents. augmented by an operational model to fill gaps. The starting points for larval transport are the locations and day of the year of larval captures from the Southeast Area Monitoring and Assessment program ichthyoplankton surveys. Because the Field Of Currents is derived front near-surface observations and the depth distribution of larvae is uncertain. findings are expressed in terms of maximal transport pathways. Transport pathways were principally vectored toward the west during September. October, and May under the influence of relatively strong climatological westward wind stress. Eastward pathways Occurred in June. July. and August under the influence of weaker shoreward wind stress. Westward transport pathways past the Mississippi delta were found near the delta. whereas eastward transport pathways were found in deeper waters beyond the continental shelf break, away front typical juvenile settlement habitat. Water movement front east to west across the Apalachicola peninsula occurred in the fall. suggesting the potential for genetic exchange front the eastern to the western Gulf. Eastward water movement across the Apalachicola peninsula occurred in July. but only along the outer shelf.
C1 [Johnson, Donald R.; Perry, Harriet M.] Univ So Mississippi, Gulf Coast Res Lab, Ocean Springs, MS 39564 USA.
[Lyczkowski-Shultz, Joanne; Hanisko, David] Natl Marine Fisheries Serv, SE Fisheries Sci Ctr, Pascagoula, MS 39567 USA.
RP Johnson, DR (reprint author), Univ So Mississippi, Gulf Coast Res Lab, 703 E Beach Dr, Ocean Springs, MS 39564 USA.
EM donald.r.johnson@usm.edu
FU National Marine Fisheries Service's Southeastern Regional Office
FX We gratefully acknowledge funding for this study from the Marine
Fisheries Initiative program of the National Marine Fisheries Service's
Southeastern Regional Office. The Study would not have been possible
without the generous contributions of data from a number of research
scientists. Many of the Current observations are from several large
Minerals Management Service (MMS) projects in the northern Gulf Of
Mexico. We would especially like to acknowledge W. Johnson (MMS) and P.
Niiler (Scripps Institution of Oceanography). Other programs involved
Florida State University and the University of South Florida. Drifter
and moored current data were provided by J. Blaha. C. Szczechowski, and
S. Dinnel (Naval Oceanographic Office). Research scientists at Texas A&M
and Louisiana State universities contributed ton CD-ROM data set that is
available through the National Oceanographic Data Center. We are
grateful to J. Waters and D. Carter (National Oceanic and Atmospheric
Administration) for discussions Oil the impact of recreational
fisheries. Finally, we acknowledge L. Kantha, who has,generously Shared
his Model data archive for several different fisheries Studies,
including this one.
NR 33
TC 9
Z9 9
U1 0
U2 13
PU AMER FISHERIES SOC
PI BETHESDA
PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 USA
SN 0002-8487
J9 T AM FISH SOC
JI Trans. Am. Fish. Soc.
PD MAY
PY 2009
VL 138
IS 3
BP 458
EP 470
DI 10.1577/T08-008.1
PG 11
WC Fisheries
SC Fisheries
GA 477EJ
UT WOS:000268501100002
ER
PT J
AU Moss, JH
Farley, EV
Feldmann, AM
Ianelli, JN
AF Moss, Jamal H.
Farley, Edward V., Jr.
Feldmann, Angela M.
Ianelli, James N.
TI Spatial Distribution, Energetic Status, and Food Habits of Eastern
Bering Sea Age-0 Walleye Pollock
SO TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY
LA English
DT Article
ID EARLY MARINE GROWTH; THERAGRA-CHALCOGRAMMA; PRIBILOF ISLANDS; PELAGIC
ECOSYSTEM; CLASS STRENGTH; SALMON; SIZE; ALASKA; SHELF; ZOOPLANKTON
AB Age-0 walleye pollock Theragra chalcogramma were collected from the eastern Bering Sea during years when ocean temperatures were anomalously warm (2004-2005) and cool (2006-2007). Variability in spatial distribution, food habits, energetic condition, and recruitment to the age-1 life stage was investigated in relation to thermal regime. Age-0 walleye pollock were large in size and widely distributed during warm years, whereas they were small and largely confined to the middle domain of the eastern Bering Sea during cool years. Energy density as positively correlated with body weight and was greater during years when conditions were anomalously cool. The proportion of smaller age-0 walleye pollock in the diet of larger individuals was high when conditions were warm (21.9% of diet by weight), and euphausiids were the most important prey (36.5% of diet by weight) when conditions were cool. Eastern Bering Sea age-0 walleye pollock were abundant and broadly distributed from Bristol Bay to offshore and northern locations during warm years: during cool years, age-0 fish were less abundant and their distribution was constricted to the southeastern Bering Sea. An inverse relationship between brood year abundance and survival from age 0 to age 1 was found. Our results indicate that when spring (summer) sea temperatures on the eastern Bering, Sea shelf are very warm and when the water column is highly stratified during summer, age-0 walleye pollock allocate more energy to growth than to lipid storage. leading to low energy density before winter and thus to higher overwinter mortality.
C1 [Moss, Jamal H.; Farley, Edward V., Jr.; Feldmann, Angela M.] Ted Stevens Marine Res Inst, Natl Marine Fisheries Serv, Alaska Fisheries Sci Ctr, Auke Bay Labs, Juneau, AK 99801 USA.
[Ianelli, James N.] Natl Marine Fisheries Serv, Alaska Fisheries Sci Ctr, Seattle, WA 98115 USA.
RP Moss, JH (reprint author), Ted Stevens Marine Res Inst, Natl Marine Fisheries Serv, Alaska Fisheries Sci Ctr, Auke Bay Labs, 17109 Point Lena Loop Rd, Juneau, AK 99801 USA.
EM jamal.moss@noaa.gov
NR 46
TC 42
Z9 45
U1 0
U2 14
PU AMER FISHERIES SOC
PI BETHESDA
PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 USA
SN 0002-8487
J9 T AM FISH SOC
JI Trans. Am. Fish. Soc.
PD MAY
PY 2009
VL 138
IS 3
BP 497
EP 505
DI 10.1577/T08-126.1
PG 9
WC Fisheries
SC Fisheries
GA 477EJ
UT WOS:000268501100005
ER
PT J
AU Sturdevant, MV
Sigler, MF
Orsi, JA
AF Sturdevant, M. V.
Sigler, M. F.
Orsi, J. A.
TI Sablefish Predation on Juvenile Pacific Salmon in the Coastal Marine
Waters of Southeast Alaska in 1999
SO TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY
LA English
DT Review
ID EARLY-LIFE-HISTORY; WHITING MERLANGIUS-MERLANGUS; PINK
ONCORHYNCHUS-GORBUSCHA; ANOPLOPOMA-FIMBRIA PALLAS; SIZE-SELECTIVE
MORTALITY; COD GADUS-MORHUA; GASTRIC EVACUATION; CHUM SALMON; DAILY
RATION; COHO SALMON
AB A1-sea observations of predation by age-1 and older (age-1+) sablefish Anoplopoma fimbria oil juvenile Pacific salmon Oncorhynchus spp. were combined with laboratory studies to determine gastric evacuation rates and were used to estimate summer predation impact in file northern region of Southeast Alaska. In June and July 1999, tip to 63% of sablefish examined from trawl catches in strait habitat had each consumed one to four juvenile pink salmon O. gorbuscha, chum salmon O. keta, or sockeye salmon O. nerka. In two laboratory experiments, field-captured sablefish were acclimated without food in compartmentalized flow-through tanks with conditions manipulated to reflect the photoperiod and temperature regimes of summer. These sablefish were each offered one whole, preweighed juvenile chum salmon: Consumption events were observed, and the sablefish were then sacrificed at predetermined time intervals. Prey biomass remaining in the stomach of each sablefish predator was weighed, and all exponential model of the decline in percent biomass over time was used to yield instantaneous evacuation rates of 0.049 at 12 degrees C and 0.027 at 7 degrees C. From field data combined with model-derived estimates of meal frequency, we estimated that 0.8-6.0 million juvenile salmon were Consumed by age-1+ sablefish in the 500-km(2) area of Icy Strait during a 33-d period. Moreover, a 10-year time series of catches indicated that 1999 was a year of unusually high age-1+ sablefish abundance and relatively low juvenile salmon abundance. We speculate that sablefish predation in 1999 Could have affected abundance of out-migrating juveniles and contributed to low harvests Of returning, adult pink salmon in 2000 and adult churn salmon in 2002. Our results suggest that sablefish predation oil juvenile Pacific salmon call occur during episodic strong year-classes of sablefish and may affect adult salmon returns.
C1 [Sturdevant, M. V.; Sigler, M. F.; Orsi, J. A.] Natl Marine Fisheries Serv, Alaska Fisheries Sci Ctr, Auke Bay Labs, Juneau, AK 99801 USA.
RP Sturdevant, MV (reprint author), Natl Marine Fisheries Serv, Alaska Fisheries Sci Ctr, Auke Bay Labs, 17109 Point Lena Loop Rd, Juneau, AK 99801 USA.
EM molly.sturdevant@noaa.gov
NR 126
TC 6
Z9 7
U1 0
U2 1
PU TAYLOR & FRANCIS INC
PI PHILADELPHIA
PA 530 WALNUT STREET, STE 850, PHILADELPHIA, PA 19106 USA
SN 0002-8487
EI 1548-8659
J9 T AM FISH SOC
JI Trans. Am. Fish. Soc.
PD MAY
PY 2009
VL 138
IS 3
BP 675
EP 691
DI 10.1577/T08-157.1
PG 17
WC Fisheries
SC Fisheries
GA 477EJ
UT WOS:000268501100019
ER
PT J
AU Mace, GG
Zhang, QQ
Vaughan, M
Marchand, R
Stephens, G
Trepte, C
Winker, D
AF Mace, Gerald G.
Zhang, Qiuqing
Vaughan, Mark
Marchand, Roger
Stephens, Graeme
Trepte, Chip
Winker, Dave
TI A description of hydrometeor layer occurrence statistics derived from
the first year of merged Cloudsat and CALIPSO data
SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
LA English
DT Article
ID HIGH-LEVEL CLOUDS; VERTICAL STRUCTURE; RADAR; MISSION; ISCCP;
CLIMATOLOGY; LIDAR; HIRS
AB The occurrence statistics of hydrometeor layers covering the Earth's surface is described using the first year of millimeter radar data collected by Cloudsat merged with lidar data collected by CALIPSO (July 2006 to June 2007). These satellites are flown in a tight orbital configuration so that they probe nearly the same volumes of the atmosphere within 10-15 s of each other. This configuration combined with the capacity for millimeter radar to penetrate optically thick hydrometeor layers and the ability of the lidar to detect optically thin clouds has allowed us to characterize the vertical and horizontal structure of hydrometeor layers with unprecedented precision. We find that the global hydrometeor coverage averages 76% and demonstrates a fairly smooth annual cycle with a range of 3% peaking in October 2006 and reaching a minimum in March 2007. The geographic distribution of hydrometeor layers defined in terms of layer base, layer top, and layer thickness is described. The predominance of geometrically thin boundary layer clouds is illustrated as is the spatial distribution of upper tropospheric ice clouds in the tropics. The cooccurrence of multiple layers is shown to be a strong function of latitude and geography with cooccurring middle-level (3 km < layer base < 6 km) and high-level (base > 6 km) layers being predominant over the continents. Cloud layer overlap is also examined, and a bias due to an assumption of maximum fractional overlap in coarse resolution models is quantified and shown to be on the order of -5 to -7% globally maximizing over the high- latitude continents of the Northern Hemisphere.
C1 [Mace, Gerald G.; Zhang, Qiuqing] Univ Utah, Dept Meteorol, Salt Lake City, UT 84112 USA.
[Marchand, Roger] Univ Washington, Joint Inst Study Atmosphere & Oceans, Seattle, WA 98105 USA.
[Vaughan, Mark; Trepte, Chip; Winker, Dave] NASA, Langley Res Ctr, Hampton, VA 23681 USA.
[Stephens, Graeme] Colorado State Univ, Dept Atmospher Sci, Ft Collins, CO 80523 USA.
RP Mace, GG (reprint author), Univ Utah, Dept Meteorol, Salt Lake City, UT 84112 USA.
FU NASA
FX We would like to acknowledge the efforts of the engineers and scientists
at the Jet Propulsion Laboratory, NASA Langley Research Center, Centre
National d'Etudes Spatiales (CNES), Ball Aerospace, and the Cooperative
Institute for Research in the Atmosphere (CIRA). Support for this work
was provided by NASA through a contract issued by the Jet Propulsion
Laboratory, California Institute of Technology under a contract with
NASA.
NR 42
TC 176
Z9 177
U1 3
U2 24
PU AMER GEOPHYSICAL UNION
PI WASHINGTON
PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA
SN 2169-897X
EI 2169-8996
J9 J GEOPHYS RES-ATMOS
JI J. Geophys. Res.-Atmos.
PD APR 30
PY 2009
VL 114
AR D00A26
DI 10.1029/2007JD009755
PG 17
WC Meteorology & Atmospheric Sciences
SC Meteorology & Atmospheric Sciences
GA 439ZN
UT WOS:000265667300001
ER
PT J
AU Preusse, P
Eckermann, SD
Ern, M
Oberheide, J
Picard, RH
Roble, RG
Riese, M
Russell, JM
Mlynczak, MG
AF Preusse, Peter
Eckermann, Stephen D.
Ern, Manfred
Oberheide, Jens
Picard, Richard H.
Roble, Raymond G.
Riese, Martin
Russell, James M., III
Mlynczak, Martin G.
TI Global ray tracing simulations of the SABER gravity wave climatology
SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
LA English
DT Article
ID CRYOGENIC INFRARED SPECTROMETERS; ATMOSPHERE RESEARCH SATELLITE;
STRATOSPHERIC MOUNTAIN WAVES; GENERAL-CIRCULATION MODELS; GPS
OCCULTATION DATA; MIDDLE ATMOSPHERE; SPECTRAL PARAMETERIZATION;
LATITUDINAL VARIATIONS; MOMENTUM DEPOSITION; CRISTA TEMPERATURES
AB Since February 2002, the SABER (sounding of the atmosphere using broadband emission radiometry) satellite instrument has measured temperatures throughout the entire middle atmosphere. Employing the same techniques as previously used for CRISTA (cryogenic infrared spectrometers and telescopes for the atmosphere), we deduce from SABER V1.06 data 5 years of gravity wave (GW) temperature variances from altitudes of 20 to 100 km. A typical annual cycle is presented by calculating averages for the individual calendar months. Findings are consistent with previous results from various satellite missions. Based on zonal mean, SABER data for July and zonal mean GW momentum flux from CRISTA, a homogeneous and isotropic launch distribution for the GROGRAT (gravity wave regional or global ray tracer) is tuned. The launch distribution contains different phase speed mesoscale waves, some of very high-phase speed and extremely low amplitudes, as well as waves with horizontal wavelengths of several thousand kilometers. Global maps for different seasons and altitudes, as well as time series of zonal mean GW squared amplitudes based on this launch distribution, match the observations well. Based on this realistic observation-tuned model run, we calculate quantities that cannot be measured directly and are speculated to be major sources of uncertainty in current GW parameterization schemes. Two examples presented in this paper are the average cross-latitude propagation of GWs and the relative acceleration contributions provided by saturation and dissipation, on the one hand, and the horizontal refraction of GWs by horizontal gradients of the mean flow, on the other hand.
C1 [Preusse, Peter; Ern, Manfred; Riese, Martin] Forschungszentrum Julich, Inst Chem & Dynam Geosphere, Res Ctr Juelich,ICG Stratosphere 1, D-52425 Julich, Germany.
[Eckermann, Stephen D.] USN, Res Lab, Div Space Sci, Washington, DC 20375 USA.
[Oberheide, Jens] Berg Univ Wuppertal, Dept Phys, D-42097 Wuppertal, Germany.
[Picard, Richard H.] USAF, Res Lab, RVBYM, Hanscom AFB, MA 01731 USA.
[Roble, Raymond G.] Natl Ctr Atmospher Res, High Altitude Observ, Boulder, CO 80307 USA.
[Russell, James M., III] Hampton Univ, Ctr Atmospher Sci, Hampton, VA 23668 USA.
[Mlynczak, Martin G.] NASA, Langley Res Ctr, Hampton, VA 23681 USA.
RP Preusse, P (reprint author), Forschungszentrum Julich, Inst Chem & Dynam Geosphere, Res Ctr Juelich,ICG Stratosphere 1, Postfach 1913, D-52425 Julich, Germany.
EM p.preusse@fz-juelich.de; stephen.eckermann@nrl.navy.mil
RI Oberheide, Jens/C-6156-2011; Mlynczak, Martin/K-3396-2012; Preusse,
Peter/A-1193-2013; Riese, Martin/A-3927-2013; Ern, Manfred/I-8839-2016
OI Oberheide, Jens/0000-0001-6721-2540; Preusse, Peter/0000-0002-8997-4965;
Riese, Martin/0000-0001-6398-6493; Ern, Manfred/0000-0002-8565-2125
FU DFG CAWSES [OB 299/2-2, ER 474/1-1]; NASA SABER Program Office; U.S. Air
Force Office of Scientific Research
FX Jens Oberheide is supported by DFG CAWSES grant OB 299/2-2. Part of the
work of Manfred Ern was supported by DFG CAWSES grant ER 474/1-1.
Richard H. Picard acknowledges support from NASA SABER Program Office
and Dr. Kent Miller of U.S. Air Force Office of Scientific Research. We
thank three anonymous reviewers for their helpful comments on the
determination of the intermittency factors, discussions, and data
presentation.
NR 87
TC 54
Z9 54
U1 4
U2 14
PU AMER GEOPHYSICAL UNION
PI WASHINGTON
PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA
SN 2169-897X
EI 2169-8996
J9 J GEOPHYS RES-ATMOS
JI J. Geophys. Res.-Atmos.
PD APR 30
PY 2009
VL 114
AR D08126
DI 10.1029/2008JD011214
PG 25
WC Meteorology & Atmospheric Sciences
SC Meteorology & Atmospheric Sciences
GA 439ZN
UT WOS:000265667300006
ER
PT J
AU Rutan, D
Rose, F
Roman, M
Manalo-Smith, N
Schaaf, C
Charlock, T
AF Rutan, David
Rose, Fred
Roman, Miguel
Manalo-Smith, Natividad
Schaaf, Crystal
Charlock, Tom
TI Development and assessment of broadband surface albedo from Clouds and
the Earth's Radiant Energy System Clouds and Radiation Swath data
product
SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
LA English
DT Article
ID REFLECTANCE DISTRIBUTION FUNCTION; BIDIRECTIONAL REFLECTANCE;
SATELLITE-OBSERVATIONS; OPTICAL-PROPERTIES; CLAMS EXPERIMENT;
VALIDATION; AEROSOL; MODEL; MODIS; RETRIEVALS
AB We describe a method to determine broadband albedo globally over land viewed by the Clouds and the Earth's Radiant Energy System (CERES) scanning radiometers on board the TRMM, Terra, and Aqua satellites. This albedo is used as a surface boundary condition for a fast radiation transfer code in the Surface and Atmospheric Radiation Budget (SARB) subsystem of the CERES processing scheme. Cloudy sky surface albedo is estimated from derived clear sky values. Clear sky surface albedo is assessed by comparing the CERES/SARB-based surface albedo with the bidirectional reflectance distribution function (BRDF)-based surface albedo supplied by the MODIS land surfaces group. The SARB method employs broadband observations at the top of atmosphere (TOA) and assumes relative spectral shape of surface albedo. The MODIS group uses higher spatial resolution observations in several shortwave window channels to retrieve spectral surface albedos and then scales up to broadband surface albedo. Comparisons over snow-free land show good agreement between the two independent products on the scale of the CERES footprint. Biases run approximately 0.005 absolute or 0.02 relative with SARB albedo, generally lower than MODIS. We find little dependence on view geometry and slight functional dependence on aerosol optical depth. The value selected for a priori surface spectral albedo is important, but not critical, when retrieving broadband surface albedo with broadband TOA data. However, based on calculations, aerosol forcing to TOA flux changes in spectral albedo shape can affect aerosol forcing for as much as would a 15% absolute change in the original broadband surface albedo.
C1 [Rutan, David; Rose, Fred; Manalo-Smith, Natividad] Sci Syst & Applicat Inc, Hampton, VA 23666 USA.
[Charlock, Tom] NASA, Langley Res Ctr, Hampton, VA 23681 USA.
[Roman, Miguel; Schaaf, Crystal] Boston Univ, Ctr Remote Sensing, Dept Geog, Boston, MA 02215 USA.
RP Rutan, D (reprint author), Sci Syst & Applicat Inc, 1 Enterprise Pkwy,Suite 200, Hampton, VA 23666 USA.
EM david.a.rutan@nasa.gov
RI Roman, Miguel/D-4764-2012;
OI Roman, Miguel/0000-0003-3953-319X; Rose, Fred G/0000-0003-0769-0772
FU NASA [NNX08AE94A]; DOE [DE-FG02-06ER64178]
FX The authors would like to thank the anonymous reviewers whose close
reading and suggestions led to a better-organized and stronger paper.
CERES data are supplied from the NASA Langley Research Center
Atmospheric Sciences Data Center. MODIS data are supplied from the NASA
Goddard Distributed Active Archive Center. ARM data are made available
through the U.S. Department of Energy as part of the Atmospheric
Radiation Measurement Program. GMD data are made available through the
NOAA's Earth System Research Laboratory/Global Monitoring
Division-Radiation (G-RAD). SURFRAD data are made available through
NOAA's Air Resources Laboratory/Surface Radiation Research Branch. IGBP
and Global Ecosystem maps are made available from the USGS Earth
Resources Observation and Science (EROS) data Center. C. Schaaf and M.
Roman are supported by NASA NNX08AE94A and DOE DE-FG02-06ER64178.
NR 51
TC 41
Z9 41
U1 1
U2 11
PU AMER GEOPHYSICAL UNION
PI WASHINGTON
PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA
SN 2169-897X
J9 J GEOPHYS RES-ATMOS
JI J. Geophys. Res.-Atmos.
PD APR 30
PY 2009
VL 114
AR D08125
DI 10.1029/2008JD010669
PG 19
WC Meteorology & Atmospheric Sciences
SC Meteorology & Atmospheric Sciences
GA 439ZN
UT WOS:000265667300003
ER
PT J
AU Wolkenberg, P
Grassi, D
Formisano, V
Rinaldi, G
D'Amore, M
Smith, M
AF Wolkenberg, P.
Grassi, D.
Formisano, V.
Rinaldi, G.
D'Amore, M.
Smith, M.
TI Simultaneous observations of the Martian atmosphere by Planetary Fourier
Spectrometer on Mars Express and Miniature Thermal Emission Spectrometer
on Mars Exploration Rover
SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
LA English
DT Article
ID WAVELENGTH CHANNEL; TEMPERATURES; CALIBRATION; RADIATION; RETRIEVAL;
MISSION; TES
AB In this study we present temperature profiles in the lower atmosphere of Mars from simultaneous observations performed by the Planetary Fourier Spectrometer (PFS) aboard the Mars Express spacecraft and the Miniature Thermal Emission Spectrometer (Mini-TES) aboard the Mars Exploration Rovers. Thermal infrared spectra were collected in both the upward and downward looking geometries from the surface and from orbit, respectively. We used two sets of criteria to select PFS observations. These criteria took into account the location around the landing sites of the rovers, the local time (LT), and the solar longitude (L-s) corresponding to the Martian solar day (sol). The first set of criteria included PFS measurements carried out within +/-1 degrees in latitude and longitude, within 1 h in local time, and on the same sol. From the restricted set of measurements we conclude that the PFS data are consistent with the Mini-TES data. The next set of criteria covered the area 5 degrees x 5 degrees around the landing sites, within 1 h in local time and within 9 sols. The latter criteria allow us to study the variation of parameters LT, distance, and Ls and their influence on changes of temperature profiles. This comparison for the group with relaxed criteria showed also that local time has strongest effect on temperature differences. The main purpose of this study is to confirm the validity of PFS temperature profiles close to the surface. Atmospheric temperatures below 5 km are retrieved from satellite measurements with a large uncertainty because of poor pieces of information in the wings of the CO2 absorption band at 667 cm(-1). The Mini-TES temperature profiles span atmospheric layers below 2 km. The good correspondence observed in a number of cases confirms the possibility of using PFS measurements to investigate the lower atmosphere.
C1 [Wolkenberg, P.; Grassi, D.; Formisano, V.; Rinaldi, G.; D'Amore, M.] INAF, IFSI, I-00133 Rome, Italy.
[Smith, M.] Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
RP Wolkenberg, P (reprint author), INAF, IFSI, Via Fosso Cavaliere 100, I-00133 Rome, Italy.
EM paulina.wolkenberg@ifsi-roma.inaf.it
RI Smith, Michael/C-8875-2012
NR 21
TC 3
Z9 3
U1 0
U2 3
PU AMER GEOPHYSICAL UNION
PI WASHINGTON
PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA
SN 2169-9097
EI 2169-9100
J9 J GEOPHYS RES-PLANET
JI J. Geophys. Res.-Planets
PD APR 30
PY 2009
VL 114
AR E04012
DI 10.1029/2008JE003216
PG 18
WC Geochemistry & Geophysics
SC Geochemistry & Geophysics
GA 440BV
UT WOS:000265674100002
ER
PT J
AU Schmidt, G
Archer, D
AF Schmidt, Gavin
Archer, David
TI CLIMATE CHANGE Too much of a bad thing
SO NATURE
LA English
DT Editorial Material
ID INTERFERENCE
C1 [Schmidt, Gavin] NASA, Goddard Inst Space Studies, New York, NY 10025 USA.
[Archer, David] Univ Chicago, Dept Geophys Sci, Chicago, IL 60637 USA.
RP Schmidt, G (reprint author), NASA, Goddard Inst Space Studies, 2880 Broadway, New York, NY 10025 USA.
EM gschmidt@giss.nasa.gov; d-archer@uchicago.edu
RI Schmidt, Gavin/D-4427-2012; Archer, David/K-7371-2012
OI Schmidt, Gavin/0000-0002-2258-0486; Archer, David/0000-0002-4523-7912
NR 8
TC 8
Z9 8
U1 0
U2 9
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 APR 30
PY 2009
VL 458
IS 7242
BP 1117
EP 1118
DI 10.1038/4581117a
PG 2
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA 441FL
UT WOS:000265754600029
PM 19407786
ER
PT J
AU Laurenza, M
Cliver, EW
Hewitt, J
Storini, M
Ling, AG
Balch, CC
Kaiser, ML
AF Laurenza, M.
Cliver, E. W.
Hewitt, J.
Storini, M.
Ling, A. G.
Balch, C. C.
Kaiser, M. L.
TI A technique for short-term warning of solar energetic particle events
based on flare location, flare size, and evidence of particle escape
SO SPACE WEATHER-THE INTERNATIONAL JOURNAL OF RESEARCH AND APPLICATIONS
LA English
DT Article
ID CORONAL MASS EJECTIONS; III RADIO-BURSTS; X-RAY FLARES; PROTON EVENTS;
MICROWAVE BURSTS; ACCELERATION; EMISSION; ELECTRON; DENSITY; SHOCKS
AB We have developed a technique to provide short-term warnings of solar energetic proton (SEP) events that meet or exceed the Space Weather Prediction Center threshold of J (>10 MeV) = 10 pr cm(-2) s(-1) sr(-1). The method is based on flare location, flare size, and evidence of particle acceleration/escape as parameterized by flare longitude, time-integrated soft X-ray intensity, and time-integrated intensity of type III radio emission at similar to 1 MHz, respectively. In this technique, warnings are issued 10 min after the maximum of >= M2 soft X-ray flares. For the solar cycle 23 (1995-2005) data on which it was developed, the method has a probability of detection of 63% (47/75), a false alarm rate of 42% (34/81), and a median warning time of similar to 55 min for the 19 events successfully predicted by our technique for which SEP event onset times were provided by Posner (2007). These measures meet or exceed verification results for competing automated SEP warning techniques but, at the present stage of space weather forecasting, fall well short of those achieved with a human (aided by techniques such as ours) making the ultimate yes/no SEP event prediction. We give some suggestions as to how our method could be improved and provide our flare and SEP event database in the auxiliary material to facilitate quantitative comparisons with techniques developed in the future.
C1 [Laurenza, M.; Storini, M.] INAF, Inst Interplanetary Space Phys, I-00133 Rome, Italy.
[Balch, C. C.] NOAA, Space Weather Predict Ctr, Boulder, CO 80305 USA.
[Cliver, E. W.; Hewitt, J.] AFRL, Space Vehicles Directorate, Hanscom AFB, MA 01731 USA.
[Ling, A. G.] Atmospher Environm Res Inc, Lexington, MA 02421 USA.
[Kaiser, M. L.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
RP Laurenza, M (reprint author), INAF, Inst Interplanetary Space Phys, Via Fosso Cavaliere 100, I-00133 Rome, Italy.
EM monica.laurenza@ifsi-roma.inaf.it
FU ASI [I/090/06/0]; European Office of Aerospace Research and Development
FX Part of the work by M. L. and M. S. was performed under COST 724 Action
and part under the ASI contract I/090/06/0. E. W. C. was supported
through the Window on Europe program of the European Office of Aerospace
Research and Development. We acknowledge a helpful discussion with Kent
Doggett of the SWPC.
NR 71
TC 28
Z9 28
U1 0
U2 1
PU AMER GEOPHYSICAL UNION
PI WASHINGTON
PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA
SN 1542-7390
J9 SPACE WEATHER
JI Space Weather
PD APR 30
PY 2009
VL 7
AR S04008
DI 10.1029/2007SW000379
PG 18
WC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology &
Atmospheric Sciences
SC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology &
Atmospheric Sciences
GA 440CQ
UT WOS:000265676400001
ER
PT J
AU Lin, WY
Zhang, MH
Wu, JB
AF Lin, Wuyin
Zhang, Minghua
Wu, Jingbo
TI Simulation of low clouds from the CAM and the regional WRF with multiple
nested resolutions
SO GEOPHYSICAL RESEARCH LETTERS
LA English
DT Article
ID PLANETARY BOUNDARY-LAYER; ATMOSPHERE; CONVECTION; STREETS; MODELS; FLOWS
AB Current climate models have shown systematic simulation biases of low clouds that have cast great uncertainties on the climate sensitivity of these models. Among them is the deficient amount of low clouds over the storm tracks. This study uses the NCAR Community Atmospheric Model (CAM) and the Weather Research and Forecasting model (WRF) to study the cause of the failure of the global model in simulating low clouds associated with a frontal passage over the North Atlantic. The global model is shown to simulate the large-scale circulation that can support the boundary layer instabilities responsible for the observed clouds, but because the global model does not resolve the unstable modes, the instability cannot be realized. The resolution requirement of cloud simulations is discussed. This study also demonstrates the feasibility of cloud parameterization by nesting high resolution models into coarse resolution models to tap into the dynamical properties of the large-scale flows. Citation: Lin, W., M. Zhang, and J. Wu (2009), Simulation of low clouds from the CAM and the regional WRF with multiple nested resolutions, Geophys. Res. Lett., 36, L08813, doi:10.1029/2008GL037088.
C1 [Lin, Wuyin; Zhang, Minghua] SUNY Stony Brook, Sch Marine & Atmospher Sci, Stony Brook, NY 11794 USA.
[Wu, Jingbo] Columbia Univ, NASA GISS, New York, NY 10025 USA.
RP Lin, WY (reprint author), SUNY Stony Brook, Sch Marine & Atmospher Sci, Stony Brook, NY 11794 USA.
EM wlin@atmsci.msrc.sunysb.edu
FU NASA MAP; DOE ARM; National Science Foundation to Stony Brook University
FX This research is supported under the NASA MAP program to Stony Brook
University. Partial support is also from the DOE ARM and CCPP program
and the National Science Foundation to Stony Brook University.
NR 21
TC 4
Z9 4
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 APR 29
PY 2009
VL 36
AR L08813
DI 10.1029/2008GL037088
PG 6
WC Geosciences, Multidisciplinary
SC Geology
GA 439YV
UT WOS:000265664800002
ER
PT J
AU Pogorzelski, RJ
AF Pogorzelski, Ronald J.
TI Beam steering dynamics in coupled oscillator based phased arrays with
coupling delay
SO RADIO SCIENCE
LA English
DT Article
AB A continuum solution for the phase evolution of a coupled oscillator array with coupling delay, when one oscillator is step detuned in time, is derived from the discrete model solution previously published. From this Green's function a differential equation is derived for the Laplace transform of the phase dynamics. The solution of this differential equation is expressed as a sum of the eigenfunctions of the differential operator for a finite length array with one oscillator detuned. The dynamic behavior of the aperture phase for beam steering is obtained by superposing two of the Green's function solutions corresponding to antisymmetric excitation at each end of the array. The far zone beam steering behavior is obtained by summing the elemental radiated signals. Generalization to planar arrays appears to be straightforward. An alternative more flexible formulation suitable for early times is also presented.
C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
RP Pogorzelski, RJ (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA.
EM ronald.j.pogorzelski@jpl.nasa.gov
FU JPL Mars Technology Program; Interplanetary Network Directorate
Technology Program; NASA
FX The work reported here was carried out at the Jet Propulsion Laboratory,
California Institute of Technology, under contract with the National
Aeronautics and Space Administration (NASA). Partial support from the
JPL Mars Technology Program, the Interplanetary Network Directorate
Technology Program, and the JPL Advanced Concepts Office of the NASA
Office of Space Exploration are gratefully acknowledged. Thanks are due
Vahraz Jamnejad of JPL for helpful theoretical discussions during the
early stages of the present work and R. A. York of the University of
California, Santa Barbara, for his early insight (circa 1998) concerning
the Sturm- Liouville nature of the differential equations and the
concomitant simple inverse Laplace transform of the Green's function
without coupling delay. Particular thanks are due Jason Martinez of
Wolfram Research for his help with the plots. Much of the computation
and graphing associated with this work was done using Mathematica1
byWolfram Research. Reference herein to any specific commercial product,
process, or service by trade name, trademark, manufacturer, or
otherwise, does not constitute or imply its endorsement by the United
States Government or the Jet Propulsion Laboratory, California Institute
of Technology.
NR 6
TC 0
Z9 0
U1 2
U2 3
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 APR 29
PY 2009
VL 44
AR RS2019
DI 10.1029/2008RS004056
PG 9
WC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology &
Atmospheric Sciences; Remote Sensing; Telecommunications
SC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology &
Atmospheric Sciences; Remote Sensing; Telecommunications
GA 440CP
UT WOS:000265676300002
ER
PT J
AU Salmun, H
Molod, A
Albrecht, J
Santos, F
AF Salmun, Haydee
Molod, Andrea
Albrecht, Jochen
Santos, Fernanda
TI Scales of variability of surface vegetation: Calculation and
implications for climate models
SO JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES
LA English
DT Article
ID CONVECTIVE BOUNDARY-LAYER; AMAZONIAN DEFORESTATION; LAND-USE; LANDSCAPE;
HETEROGENEITY; AGGREGATION; IMPACT; RESOLUTION; PATTERNS; FLUXES
AB The presence in the vegetation landscape of many varied scales of organization implies a complex set of land/atmosphere interactions. Larger scales of variability at the surface induce boundary layer heterogeneity and may induce secondary boundary layer circulation patterns. The quantification of the scales of heterogeneity in the surface vegetation, therefore, is essential to the understanding and modeling of the land/atmosphere interactions. The present study analyzes the scales of heterogeneity in the surface vegetation by using a satellite-derived land class category map and a discrete analysis tool. Results show substantial variability in scales near 1000 km for most land class categories other than Deciduous Broadleaf Forest. Implications for GCM modeling approaches to the land/atmosphere interactions were drawn based on the results of the study. Results are consistent with the use of a 'mosaic' rather than a 'mixture' approach and with extending the 'mosaic' approach up through the boundary layer.
C1 [Salmun, Haydee; Albrecht, Jochen; Santos, Fernanda] CUNY Hunter Coll, Dept Geog, New York, NY 10065 USA.
[Molod, Andrea] Univ Maryland Baltimore Cty, Goddard Modeling & Assimilat Off, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA.
RP Salmun, H (reprint author), CUNY Hunter Coll, Dept Geog, 695 Pk Ave, New York, NY 10065 USA.
EM hsalmun@hunter.cuny.edu
OI Santos, Fernanda/0000-0001-9155-5623
FU CUNY Research Foundation through PSC-CUNY award [65266-00 34]; NSF's
ADVANCE [0620087]; Society of Women Geographers
FX We gratefully acknowledge the partial support for this work provided the
CUNY Research Foundation through PSC-CUNY award 65266-00 34. Final
stages of the analysis and the writing of this manuscript were
accomplished under the auspices of the NSF's ADVANCE grant 0620087. F.
S. was partially supported by an award from the Society of Women
Geographers, and the calculations she contributed to this work
constitute an M. A. thesis in the Department of Geography at Hunter
College of CUNY. The authors also wish to acknowledge the constructive
critique of the two anonymous reviewers.
NR 36
TC 3
Z9 3
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-BIOGEO
JI J. Geophys. Res.-Biogeosci.
PD APR 28
PY 2009
VL 114
AR G02007
DI 10.1029/2008JG000762
PG 13
WC Environmental Sciences; Geosciences, Multidisciplinary
SC Environmental Sciences & Ecology; Geology
GA 440AC
UT WOS:000265669000001
ER
PT J
AU Gounelle, M
Chaussidon, M
Morbidelli, A
Barrat, JA
Engrand, C
Zolensky, ME
McKeegan, KD
AF Gounelle, Matthieu
Chaussidon, Marc
Morbidelli, Alessandro
Barrat, Jean-Alix
Engrand, Cecile
Zolensky, Michael E.
McKeegan, Kevin D.
TI A unique basaltic micrometeorite expands the inventory of solar system
planetary crusts
SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF
AMERICA
LA English
DT Article
DE asteroids; cosmic dust; differentiation
ID ANTARCTIC MICROMETEORITES; COSMIC SPHERULES; OXYGEN ISOTOPES; ACCRETION
RATE; PARENT BODY; SOUTH-POLE; MAIN BELT; METEORITES; VESTA; COLLECTION
AB Micrometeorites with diameter approximate to 100-200 mu m dominate the flux of extraterrestrial matter on Earth. The vast majority of micrometeorites are chemically, mineralogically, and isotopically related to carbonaceous chondrites, which amount to only 2.5% of meteorite falls. Here, we report the discovery of the first basaltic micrometeorite (MM40). This micrometeorite is unlike any other basalt known in the solar system as revealed by isotopic data, mineral chemistry, and trace element abundances. The discovery of a new basaltic asteroidal surface expands the solar system inventory of planetary crusts and underlines the importance of micrometeorites for sampling the asteroids' surfaces in a way complementary to meteorites, mainly because they do not suffer dynamical biases as meteorites do. The parent asteroid of MM40 has undergone extensive metamorphism, which ended no earlier than 7.9 Myr after solar system formation. Numerical simulations of dust transport dynamics suggest that MM40 might originate from one of the recently discovered basaltic asteroids that are not members of the Vesta family. The ability to retrieve such a wealth of information from this tiny (a few micrograms) sample is auspicious some years before the launch of a Mars sample return mission.
C1 [Gounelle, Matthieu] CNRS, UMR 7202, Lab Mineral, F-75005 Paris, France.
[Gounelle, Matthieu] CNRS, UMR 7202, Museum Natl Hist Nat, Cosmochim Museum, F-75005 Paris, France.
[Chaussidon, Marc] Nancy Univ, CNRS, UPR 2300, Ctr Rech Petrog & Geochim, Notre Dame Des Pauvres, France.
[Morbidelli, Alessandro] Observ Cote Azur, F-06304 Nice, France.
[Barrat, Jean-Alix] Univ Bretagne Occidentale, Inst Univ Europeen Mer, CNRS, UMR 6538 Domaines Ocean, F-29280 Plouzane, France.
[Engrand, Cecile] Univ Paris 11, Ctr Spectrometrie Nucl & Spectrometrie Masse, CNRS, F-91405 Orsay, France.
[Zolensky, Michael E.] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA.
[McKeegan, Kevin D.] Univ Calif Los Angeles, Dept Earth & Space Sci, Los Angeles, CA 90095 USA.
RP Gounelle, M (reprint author), CNRS, UMR 7202, Lab Mineral, CP52,57 Rue Cuvier, F-75005 Paris, France.
EM gounelle@mnhn.fr
RI McKeegan, Kevin/A-4107-2008; Jean-Alix, BARRAT/F-8035-2012; UCLA,
SIMS/A-1459-2011; Barrat, Jean-Alix/C-8416-2017; Chaussidon,
Marc/E-7067-2017
OI McKeegan, Kevin/0000-0002-1827-729X; Barrat,
Jean-Alix/0000-0003-3158-3109;
FU Program National de Planetologie (PNP); Centre National de la Recherche
Scientifique [2006-3482]; European Grant ORIGINS [MRTN-CT-2006-035519];
Institut Polaire Francais Paul-Emile Victor (IPEV)
FX We thank Michel Maurette and Gero Kurat for their pioneering work on
micrometeorites and for fruitful discussions and insights on the origin
of this particle, and two anonymous reviewers for their very
constructive comments, and for bringing our attention to the basaltic
clasts in ordinary chondrites. This work was supported by the Program
National de Planetologie (PNP), the France-Etats-Unis fund from Centre
National de la Recherche Scientifique [2006-3482], and European Grant
ORIGINS [MRTN-CT-2006-035519]. The Institut Polaire Francais Paul-Emile
Victor (IPEV) constantly supported the efforts of the Orsay group to
collect micrometeorites. This is CRPG contribution # 1989.
NR 47
TC 18
Z9 18
U1 1
U2 4
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 APR 28
PY 2009
VL 106
IS 17
BP 6904
EP 6909
DI 10.1073/pnas.0900328106
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA 438VS
UT WOS:000265584500009
PM 19366660
ER
PT J
AU Hiraga, JS
Kobayashi, Y
Tamagawa, T
Hayato, A
Bamba, A
Terada, Y
Petre, R
Katagiri, H
Tsunemi, H
AF Hiraga, Junko S.
Kobayashi, Yusuke
Tamagawa, Toru
Hayato, Asami
Bamba, Aya
Terada, Yukikatsu
Petre, Robert
Katagiri, Hideaki
Tsunemi, Hiroshi
TI Search for Sc-K Line Emission from RX J0852.0-4622 Supernova Remnant
with Suzaku
SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN
LA English
DT Article
DE ISM: supernova remnant; X-ray: individual [RX J0852.0-4622 (Vela Jr.)]
ID X-RAY; GALACTIC SUPERNOVA; BOARD SUZAKU; TI-44; J0852-4642; CASSIOPEIA;
CAS
AB We searched for evidence of line emission around 4 keV from the northwestern rim of the supernova remnant RX J0852.0-4622 using Suzaku XIS data. Several papers have reported on the detection of an emission line around 4.1 keV from this region of the sky. This line Would arise from K-band fluorescence by Sc-44, the immediate decay product of Ti-44. We performed spectral analysis for the entire portion of the NW rim of the remnant within the XIS field of view, as well as various regions corresponding to regions of published claims of line emission. We found no line emission around 4.1 keV anywhere, and are able to set a restrictive Upper limit to the X-ray flux: 1.1 x 10(-6) s(-1) cm(-2) for the entire field. For every region, our flux upper limit falls below that of the previously claimed detection. Therefore, we conclude that, to date, no definite X-ray line feature from Sc-K emission has been detected in the NW rim of RX J0852.0-4622. Our negative-detection supports the recent claim that RX J0852-4622 is neither young (1700-4000 yr) nor nearby (similar to 750 pc).
C1 [Hiraga, Junko S.; Tamagawa, Toru; Hayato, Asami] RIKEN, Wako, Saitama 3510198, Japan.
[Kobayashi, Yusuke; Bamba, Aya] Japan Aerosp Explorat Agcy, Inst Space & Astronaut Sci, Sagamihara, Kanagawa 2298510, Japan.
[Tamagawa, Toru; Hayato, Asami] Tokyo Univ Sci, Dept Phys, Shinjuku Ku, Tokyo 1628601, Japan.
[Terada, Yukikatsu] Saitama Univ, Dept Phys, Sakura Ku, Saitama 3388570, Japan.
[Petre, Robert] NASA, Goddard Space Flight Ctr, Astrophys Sci Div, Greenbelt, MD 20771 USA.
[Katagiri, Hideaki] Hiroshima Univ, Grad Sch Sci, Dept Phys Sci, Hiroshima 7398526, Japan.
[Tsunemi, Hiroshi] Osaka Univ, Grad Sch Sci Earth & Space Sci, Osaka 5600043, Japan.
RP Hiraga, JS (reprint author), RIKEN, 2-1 Hirosawa, Wako, Saitama 3510198, Japan.
EM jhiraga@crab.riken.jp
RI Terada, Yukikatsu/A-5879-2013; XRAY, SUZAKU/A-1808-2009
OI Terada, Yukikatsu/0000-0002-2359-1857;
NR 20
TC 10
Z9 10
U1 0
U2 1
PU OXFORD UNIV PRESS
PI OXFORD
PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND
SN 0004-6264
EI 2053-051X
J9 PUBL ASTRON SOC JPN
JI Publ. Astron. Soc. Jpn.
PD APR 25
PY 2009
VL 61
IS 2
BP 275
EP 281
DI 10.1093/pasj/61.2.275
PG 7
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 447YP
UT WOS:000266228300012
ER
PT J
AU Uchida, H
Tsunemi, H
Katsuda, S
Kimura, M
Kosugi, H
AF Uchida, Hiroyuki
Tsunemi, Hiroshi
Katsuda, Satoru
Kimura, Masashi
Kosugi, Hiroko
TI Ejecta Distributions of Heavy Elements in the Cygnus Loop
SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN
LA English
DT Article
DE ISM: abundances; ISM: individual (Cygnus Loop); ISM: supernova remnants;
X-rays: ISM
ID X-RAY-SPECTRUM; SUPERNOVA REMNANT; NORTHEASTERN RIM; SOUTHWESTERN RIM;
PLASMA STRUCTURE; SUZAKU; EMISSION; NUCLEOSYNTHESIS; ABSORPTION;
EXPLOSION
AB We analyzed the metal distribution of the Cygnus Loop using 14 and 7 pointing observation data obtained by the Suzaku and XMM-Newton observatories, respectively. The spectral analysis shows that all of the spectra are well fitted by a two-kT(e) nonequilibrium ionization plasma model, as shown by earlier observations. From the best-fit parameters of the high-kT(e), component, we calculated the emission measures about Various elements. and showed the metal distribution of the ejecta component. We found that the distributions of Si and Fe are centered South of the geometric center toward the blow-out region. From the best-fit parameters, we also estimated the progenitor mass of the Cygnus Loop from our field of view (FOV) and the metal-rich region with a radius of 25' from the metal center. The result obtained from the metal circle is similar to that obtained from our entire FOV which suggests a mixing of the metal. From the results, the mass of the progenitor star was estimated at 12-15 M-circle dot.
C1 [Uchida, Hiroyuki; Tsunemi, Hiroshi; Katsuda, Satoru; Kimura, Masashi; Kosugi, Hiroko] Osaka Univ, Grad Sch Sci, Dept Earth & Space Sci, Osaka 5600043, Japan.
[Katsuda, Satoru] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
RP Uchida, H (reprint author), Osaka Univ, Grad Sch Sci, Dept Earth & Space Sci, Osaka 5600043, Japan.
EM uchida@ess.sci.osaka-u.ac.jp
RI XRAY, SUZAKU/A-1808-2009
FU Ministry of Education, Culture, Sports, Science and Technology
[16002004]; JSPS Research Fellowship for Young Scientists
FX This work is partly supported by a Grant-in-Aid for Scientific Research
by the Ministry of Education, Culture, Sports, Science and Technology
(16002004). This study is also carried out as part of the 21st Century
COE Program, "Towards a new basic science: depth and synthesis". H. U.
and S. K. are supported by JSPS Research Fellowship for Young
Scientists.
NR 33
TC 10
Z9 10
U1 0
U2 0
PU OXFORD UNIV PRESS
PI OXFORD
PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND
SN 0004-6264
EI 2053-051X
J9 PUBL ASTRON SOC JPN
JI Publ. Astron. Soc. Jpn.
PD APR 25
PY 2009
VL 61
IS 2
BP 301
EP 308
DI 10.1093/pasj/61.2.301
PG 8
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 447YP
UT WOS:000266228300015
ER
PT J
AU Cravens, TE
McNutt, RL
Waite, JH
Robertson, IP
Luhmann, JG
Kasprzak, W
Ip, WH
AF Cravens, T. E.
McNutt, R. L., Jr.
Waite, J. H., Jr.
Robertson, I. P.
Luhmann, J. G.
Kasprzak, W.
Ip, W. -H.
TI Plume ionosphere of Enceladus as seen by the Cassini ion and neutral
mass spectrometer
SO GEOPHYSICAL RESEARCH LETTERS
LA English
DT Article
ID SATURNS MAGNETOSPHERE; PLASMA; ATMOSPHERE; CHEMISTRY; DYNAMICS
AB The Cassini spacecraft passed within 168 km of the surface of Enceladus on 14 July 2005 during the E2 flyby and passed closer (50 km) during the E3 encounter on 13 March 2008. During both flybys the ion and neutral mass spectrometer (INMS) detected a plume atmosphere mainly composed of water. During the E3 flyby, the INMS measured an ion mass spectrum with a large peak at mass number of 19 Daltons (interpreted as H(3)O(+) ions) but not at the mass numbers of other water group ion species (including H(2)O(+), OH(+), O(+)). In addition, the INMS observed ion species at mass numbers 36 and 37 possibly the water cluster ion species H(2)O(+) - H(2)O and H(3)O(+) - H(2)O. The INMS detection of cold H3O+ in the plume combined with the almost complete absence of cold H2O+ ions is attributed to an active ion-neutral chemistry operating in a plume "ionosphere.'' Citation: Cravens, T. E., R. L. McNutt Jr., J. H. Waite Jr., I. P. Robertson, J. G. Luhmann, W. Kasprzak, and W.-H. Ip (2009), Plume ionosphere of Enceladus as seen by the Cassini ion and neutral mass spectrometer, Geophys. Res. Lett., 36, L08106, doi:10.1029/2009GL037811.
C1 [Cravens, T. E.; Robertson, I. P.] Univ Kansas, Dept Phys & Astron, Lawrence, KS 66045 USA.
[Ip, W. -H.] Natl Cent Univ, Inst Astron, Jhongli 32001, Taiwan.
[Ip, W. -H.] Natl Cent Univ, Inst Space Sci, Jhongli 32001, Taiwan.
[Kasprzak, W.] NASA, Goddard Spaceflight Ctr, Greenbelt, MD 20771 USA.
[Luhmann, J. G.] Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA.
[McNutt, R. L., Jr.] Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA.
[Waite, J. H., Jr.] SW Res Inst, San Antonio, TX 78238 USA.
RP Cravens, TE (reprint author), Univ Kansas, Dept Phys & Astron, 1251 Wescoe Hall Dr, Lawrence, KS 66045 USA.
EM cravens@ku.edu
RI McNutt, Ralph/E-8006-2010
OI McNutt, Ralph/0000-0002-4722-9166
FU NASA Cassini [NFP45280]
FX Support from the NASA Cassini project ( grant NFP45280 via subcontract
from Southwest Research Institute) is acknowledged.
NR 25
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 APR 24
PY 2009
VL 36
AR L08106
DI 10.1029/2009GL037811
PG 4
WC Geosciences, Multidisciplinary
SC Geology
GA 438CR
UT WOS:000265534000003
ER
PT J
AU Choi, HJ
Chun, HY
Song, IS
AF Choi, Hyun-Joo
Chun, Hye-Yeong
Song, In-Sun
TI Gravity wave temperature variance calculated using the ray-based
spectral parameterization of convective gravity waves and its comparison
with Microwave Limb Sounder observations
SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
LA English
DT Article
ID MOMENTUM FLUX SPECTRUM; LARGE-SCALE MODELS; DRAG PARAMETERIZATION;
CUMULUS CONVECTION; MIDDLE ATMOSPHERE; STRATOSPHERE; FORMULATION;
REANALYSIS; GENERATION
AB The ray-based spectral parameterization of convective gravity wave drag, which explicitly calculates the gravity wave propagation properties, is validated against the Microwave Limb Sounder (MLS) on the Upper Atmosphere Research Satellite (UARS). Offline calculations of the ray-based parameterization are performed using global reanalysis data and gravity wave temperature variances calculated from the parameterization are compared with those measured from the MLS. The parameterized temperature variances are calculated from gravity wave packets that are visible from the MLS to allow for comparison. The MLS visibility is analytically obtained using the three-dimensional MLS filter function. Comparisons between the parameterization calculations and MLS measurements show that both the magnitude and spatial distribution of the MLS-filtered temperature variances in the ray-based parameterization are in good agreement with observations. However, the MLS-filtered temperature variances are found to be sensitive to the source-level wave propagation direction, which, until now, has been regarded as a free parameter in the ray-based parameterization. This result indicates that the wave propagation direction can be crucial for more realistic parameterization of gravity wave (GW) effects and thus needs to be reasonably determined. Comparisons between the ray-based parameterization and columnar parameterization, which considers the gravity wave propagation only in the vertical direction, are also made in terms of temperature variance, and both results, after filtered, are similar to MLS observations. However, the magnitude of the unfiltered temperature variance in the equatorial regions with weak MLS visibility is smaller in the ray-based parameterization than in the columnar parameterization.
C1 [Choi, Hyun-Joo; Chun, Hye-Yeong] Yonsei Univ, Dept Atmospher Sci, Seoul 120749, South Korea.
[Song, In-Sun] Univ Maryland, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21201 USA.
[Song, In-Sun] NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Greenbelt, MD 20771 USA.
RP Choi, HJ (reprint author), Yonsei Univ, Dept Atmospher Sci, 262 Seongsanno, Seoul 120749, South Korea.
EM chunhy@yonsei.ac.kr
FU Ministry of Science and Technology of Korea [M10500000114-06J0000-11410]
FX This work was supported by the Ministry of Science and Technology of
Korea through the National Research Laboratory Program
(M10500000114-06J0000-11410). The DCH data set was provided by the
cooperative research project of the NCEP-DOE Atmospheric Model
Intercomparison Project (AMIP-II) reanalysis (R-2) by NCEP and DOE. The
ECMWF ERA-40 reanalysis data set was provided by ECMWF from their data
server.
NR 36
TC 16
Z9 16
U1 1
U2 5
PU AMER GEOPHYSICAL UNION
PI WASHINGTON
PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA
SN 2169-897X
EI 2169-8996
J9 J GEOPHYS RES-ATMOS
JI J. Geophys. Res.-Atmos.
PD APR 24
PY 2009
VL 114
AR D08111
DI 10.1029/2008JD011330
PG 11
WC Meteorology & Atmospheric Sciences
SC Meteorology & Atmospheric Sciences
GA 438DB
UT WOS:000265535000006
ER
PT J
AU Suess, ST
Ko, YK
von Steiger, R
Moore, RL
AF Suess, S. T.
Ko, Y. -K.
von Steiger, R.
Moore, R. L.
TI Quiescent current sheets in the solar wind and origins of slow wind
SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
LA English
DT Article
ID CORONAL MASS EJECTION; HELIOSPHERIC CURRENT SHEET; PHYSICAL-PROPERTIES;
HELIUM ABUNDANCE; STREAMER BOUNDARIES; FLOW; EVOLUTION; SPEEDS; FLARES;
AU
AB Solar wind near the heliospheric current sheet is investigated using Ulysses and ACE data in a superposed epoch analysis for several days on either side of the current sheets. Only data near sunspot minima are used, minimizing the influence of transients. New results are shown for composition and ionization state. Existing results showing a similar to 2 day wide depletion in He/H (He(++)/H(+)) at the current sheet are confirmed, although the depletion is generally more narrow. A recent finding of a broad 5-10 day wide reduction in He/H around the current sheet is also confirmed. An important result is that the narrow depletion is not a real phenomenon but is instead a statistical consequence of the superposition of transient depletions that also create the broad reduction in the averages. These transient depletions last from a few hours up to several days, come from the core of streamers, and are embedded in a quasi-steady flow from streamers' legs. Most depletions contain a current sheet just inside one edge, leading to the apparent narrow depletion at the current sheet in the superposed epoch analysis. These results lead us to a hypothesis for how the He/H depletions form with a current sheet just inside one edge. Fe/O fluctuations associated with the He/H fluctuations further show that mixing of plasma from coronal holes adjacent to streamer brightness boundaries into outflow inside the brightness boundary is not an important process.
C1 [Suess, S. T.] NASA, George C Marshall Space Flight Ctr, Natl Space Sci & Technol Ctr, Huntsville, AL 35812 USA.
[Ko, Y. -K.] USN, Res Lab, Washington, DC 20375 USA.
[von Steiger, R.] Int Space Sci Inst, Bern, Switzerland.
RP Suess, ST (reprint author), NASA, George C Marshall Space Flight Ctr, Natl Space Sci & Technol Ctr, Mail Code VP62, Huntsville, AL 35812 USA.
EM stevesuess@bellsouth.net; yko@ssd5.nrl.navy.mil; vsteiger@issibern.ch;
ronald.1.moore@nasa.gov
RI Von Steiger, Rudolf/F-6822-2011
OI Von Steiger, Rudolf/0000-0002-3350-0023
FU ONR; NASA [NNX07AL72G]
FX We would like to thank the International Space Science Institute, Bern,
Switzerland, for the hospitality provided to our team studying the Role
of Current Sheets in Solar Eruptive Phenomena, where many of the ideas
presented in this work have been discussed. S. T. S. thanks the
Ulysses/SWOOPS instrument team for its long support of his research and
the Osservatorio Astrofisico di Arcetri for its hospitality while much
of this paper was being written. Y. K. K. acknowledges the support by
ONR and NASA grant NNX07AL72G.
NR 38
TC 26
Z9 26
U1 0
U2 1
PU AMER GEOPHYSICAL UNION
PI WASHINGTON
PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA
SN 0148-0227
J9 J GEOPHYS RES-SPACE
JI J. Geophys. Res-Space Phys.
PD APR 24
PY 2009
VL 114
AR A04103
DI 10.1029/2008JA013704
PG 18
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 438EQ
UT WOS:000265539100002
ER
PT J
AU Wu, EYS
Ade, P
Bock, J
Bowden, M
Brown, ML
Cahill, G
Castro, PG
Church, S
Culverhouse, T
Friedman, RB
Ganga, K
Gear, WK
Gupta, S
Hinderks, J
Kovac, J
Lange, AE
Leitch, E
Melhuish, SJ
Memari, Y
Murphy, JA
Orlando, A
Piccirillo, L
Pryke, C
Rajguru, N
Rusholme, B
Schwarz, R
O'Sullivan, C
Taylor, AN
Thompson, KL
Turner, AH
Zemcov, M
AF Wu, E. Y. S.
Ade, P.
Bock, J.
Bowden, M.
Brown, M. L.
Cahill, G.
Castro, P. G.
Church, S.
Culverhouse, T.
Friedman, R. B.
Ganga, K.
Gear, W. K.
Gupta, S.
Hinderks, J.
Kovac, J.
Lange, A. E.
Leitch, E.
Melhuish, S. J.
Memari, Y.
Murphy, J. A.
Orlando, A.
Piccirillo, L.
Pryke, C.
Rajguru, N.
Rusholme, B.
Schwarz, R.
O'Sullivan, C.
Taylor, A. N.
Thompson, K. L.
Turner, A. H.
Zemcov, M.
CA QUaD Collaboration
TI Parity Violation Constraints Using Cosmic Microwave Background
Polarization Spectra from 2006 and 2007 Observations by the QUaD
Polarimeter
SO PHYSICAL REVIEW LETTERS
LA English
DT Article
ID LORENTZ; PROBE; CMB
AB We constrain parity-violating interactions to the surface of last scattering using spectra from the QUaD experiment's second and third seasons of observations by searching for a possible systematic rotation of the polarization directions of cosmic microwave background photons. We measure the rotation angle due to such a possible "cosmological birefringence" to be 0.55 degrees +/- 0.82 degrees (random) +/- 0.5 degrees (systematic) using QUaD's 100 and 150 GHz temperature-curl and gradient-curl spectra over the spectra over the multipole range 200
80 eV, providing for the first time direct evidence of the stark temperature disparity between the two sides of an astrophysical CD and constraining the role of magnetic fields and heat conduction accordingly. Two colliding-wind binaries are noted to have similar RRCs suggesting a temperature jump, and CD crossing by ions may be a common feature of stellar-wind shocks.
C1 [Nordon, Raanan; Behar, Ehud; Soker, Noam] Technion Israel Inst Technol, Dept Phys, IL-32000 Haifa, Israel.
[Kastner, Joel H.; Yu, Young Sam] Rochester Inst Technol, Ctr Imaging Sci, Rochester, NY 14623 USA.
[Behar, Ehud] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
RP Nordon, R (reprint author), Max Planck Inst Extraterr Phys, Postfach 1312, D-85741 Garching, Germany.
EM nordon@mpe.mpg.de; behar@milkyway.gsfc.nasa.gov;
soker@physics.technion.ac.il; jhkpci@cis.rit.edu; yxy7181@cis.rit.edu
FU NASA [GO5-6008X, NAS8-03060]
FX We thank A. Laor, M. Leutenegger, and J. Raymond for useful discussions
and comments. The research at Rochester Institute of Technology was
supported by NASA through Chandra award GO5-6008X issued by the Chandra
X-ray observatory center, which is operated by the Smithsonian
Astrophysical Observatory for and on behalf of NASA under contract
NAS8-03060.
NR 40
TC 3
Z9 3
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 APR 20
PY 2009
VL 695
IS 2
BP 834
EP 843
DI 10.1088/0004-637X/695/2/834
PG 10
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 430VS
UT WOS:000265018300005
ER
PT J
AU Geballe, TR
Saumon, D
Golimowski, DA
Leggett, SK
Marley, MS
Noll, KS
AF Geballe, T. R.
Saumon, D.
Golimowski, D. A.
Leggett, S. K.
Marley, M. S.
Noll, K. S.
TI SPECTROSCOPIC DETECTION OF CARBON MONOXIDE IN TWO LATE-TYPE T DWARFS
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE infrared: general; stars: individual (Gliese 570D, 2MASS
J09373487+2931409); stars: low-mass, brown dwarfs
ID GLIESE 229B; BROWN DWARFS; SPECTRAL CLASSIFICATION; ATMOSPHERIC
CHEMISTRY; CHEMICAL-EQUILIBRIUM; ULTRACOOL DWARFS; SOLAR-SYSTEM;
ABUNDANCES; PHOTOMETRY; JUPITER
AB M-band spectra of two late-type T dwarfs, 2MASS J09373487+2931409, and Gliese 570D, confirm evidence from photometry that photospheric carbon monoxide (CO) is present at abundance levels far in excess of those predicted from chemical equilibrium. These new and unambiguous detections of CO, together with an earlier spectroscopic detection of CO in Gliese 229B and existing M-band photometry of a large selection of T dwarfs, suggest that vertical mixing in the photosphere drives the CO abundance out of chemical equilibrium and is a common, and likely universal feature of mid-to-late-type T dwarfs. The M-band spectra allow determinations of the timescale of vertical mixing in the radiative region of the atmosphere of each object, the first such measurements of this important parameter in late T dwarfs. A detailed analysis of the spectral energy distribution of 2MASS J09373487+2931409 results in the following values for metallicity, temperature, surface gravity, and luminosity: [M/H] similar to -0.3, T(eff) = 925-975 K, log g = 5.20-5.47, and log L/L(circle dot) = -5.308 +/- 0.027. The age is 3-10 Gyr and the mass is in the range 45-69 M(Jup).
C1 [Geballe, T. R.; Leggett, S. K.] Gemini Observ, Hilo, HI 96720 USA.
[Saumon, D.] Los Alamos Natl Lab, Los Alamos, NM 87545 USA.
[Golimowski, D. A.] Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA.
[Marley, M. S.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA.
[Noll, K. S.] Space Telescope Sci Inst, Baltimore, MD 21218 USA.
RP Geballe, TR (reprint author), Gemini Observ, 670 N Aohoku Pl, Hilo, HI 96720 USA.
EM tgeballe@gemini.edu
RI Noll, Keith/C-8447-2012; Marley, Mark/I-4704-2013
NR 47
TC 34
Z9 34
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 APR 20
PY 2009
VL 695
IS 2
BP 844
EP 854
DI 10.1088/0004-637X/695/2/844
PG 11
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 430VS
UT WOS:000265018300006
ER
PT J
AU Jung, YD
AF Jung, Young-Dae
TI RESONANT COMPTON SCATTERING IN NONTHERMAL ASTROPHYSICAL PLASMAS
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE atomic data; atomic processes; plasmas
ID DEBYE LENGTH; ELECTRONS
AB The nonthermal effect on the resonant Compton scattering process is investigated in Lorentzian astrophysical plasmas. The screened atomic wave functions and energies for the hydrogenic ion in Lorentzian plasmas are obtained by the Rayleigh-Ritz variational method. The resonance Compton scattering cross section in Lorentzian plasmas is also obtained as a function of the spectral index and plasma parameters by the photon-perturbation Hamiltonian in the dipole representation. It is shown that the nonthermal character of the Lorentzian plasma enhances the resonant Compton scattering cross section. In addition, the nonthermal effect on the cross section is found to be more significant in plasmas with higher densities.
C1 [Jung, Young-Dae] Hanyang Univ, Dept Appl Phys, Ansan 426791, Kyunggi Do, South Korea.
[Jung, Young-Dae] NASA, George C Marshall Space Flight Ctr, Natl Space Sci & Technol Ctr, Huntsville, AL 35805 USA.
RP Jung, YD (reprint author), Hanyang Univ, Dept Appl Phys, Ansan 426791, Kyunggi Do, South Korea.
EM ydjung@hanyang.ac.kr
FU Korean Government [KRF-2007-313-C00169]
FX The author gratefully acknowledges S. L. O'Dell and M. Weisskopf for
useful discussions and warm hospitality while visiting NASA/Marshall
Space Flight Center. The author would like to thank S. Federman and the
anonymous referee for suggesting improvements to this text. This work
was supported by the Korea Research Foundation Grant funded by the
Korean Government (MOEHRD, Basic Research Promotion Fund;
KRF-2007-313-C00169).
NR 19
TC 11
Z9 11
U1 0
U2 3
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 APR 20
PY 2009
VL 695
IS 2
BP 917
EP 920
DI 10.1088/0004-637X/695/2/917
PG 4
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 430VS
UT WOS:000265018300013
ER
PT J
AU Birn, J
Fletcher, L
Hesse, M
Neukirch, T
AF Birn, J.
Fletcher, L.
Hesse, M.
Neukirch, T.
TI ENERGY RELEASE AND TRANSFER IN SOLAR FLARES: SIMULATIONS OF
THREE-DIMENSIONAL RECONNECTION
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE MHD; Sun: corona; Sun: magnetic fields
ID X-RAY SOURCES; MAGNETIC RECONNECTION; FLUX ROPES; CHROMOSPHERIC
EVAPORATION; PARTICLE-ACCELERATION; EMISSION MEASURE; ACTIVE-REGION;
ALFVEN WAVES; TEMPERATURE; EVOLUTION
AB Using three-dimensional magnetohydrodynamic simulations we investigate energy release and transfer in a three-dimensional extension of the standard two-ribbon flare picture. In this scenario, reconnection is initiated in a thin current sheet (suggested to form below a departing coronal mass ejection) above a bipolar magnetic field. Two cases are contrasted: an initially force-free current sheet (low beta) and a finite-pressure current sheet (high beta), where beta represents the ratio between gas (plasma) and magnetic pressure. The energy conversion process from reconnection consists of incoming Poynting flux turned into up-and downgoing Poynting flux, enthalpy flux, and bulk kinetic energy flux. In the low-beta case, the outgoing Poynting flux is the dominant contribution, whereas the outgoing enthalpy flux dominates in the high-beta case. The bulk kinetic energy flux is only a minor contribution in the downward direction. The dominance of the downgoing Poynting flux in the low-beta case is consistent with an alternative to the thick target electron beam model for solar flare energy transport, suggested recently by Fletcher & Hudson, whereas the enthalpy flux may act as an alternative transport mechanism. For plausible characteristic parameters of the reconnecting field configuration, we obtain energy release timescales and energy output rates that compare favorably with those inferred from observations for the impulsive phase of flares. Significant enthalpy flux and heating are found even in the initially force-free case with very small background beta, resulting mostly from adiabatic compression rather than Ohmic dissipation. The energy conversion mechanism is most easily understood as a two-step process (although the two steps may occur essentially simultaneously): the first step is the acceleration of the plasma by Lorentz forces in layers akin to the slow shocks in the Petschek reconnection model, involving the conversion of magnetic energy to bulk kinetic energy. However, due to pressure gradient forces that oppose the Lorentz forces in approximate, or partial force balance, the accelerated plasma becomes slowed down and compressed, whereby the bulk kinetic energy is converted to heat, either locally deposited or transported away by enthalpy flux and deposited later. This mechanism is most relevant in the downflow region, which is more strongly governed by force balance; it is less important in the outflow above the reconnection site, where more energy remains in the form of fast bulk flow.
C1 [Birn, J.] Los Alamos Natl Lab, Los Alamos, NM 87545 USA.
[Fletcher, L.] Univ Glasgow, Glasgow G12 8QQ, Lanark, Scotland.
[Hesse, M.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
[Neukirch, T.] Univ St Andrews, St Andrews KY16 9AJ, Fife, Scotland.
RP Birn, J (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA.
EM jbirn@lanl.gov
RI Neukirch, Thomas/C-1981-2009; Hesse, Michael/D-2031-2012; NASA MMS,
Science Team/J-5393-2013
OI Neukirch, Thomas/0000-0002-7597-4980; NASA MMS, Science
Team/0000-0002-9504-5214
FU US Department of Energy; NASA; UK STFC [ST/F002637]; European Commission
[MTRNCT-2006-035484]
FX This work was conducted under the auspices of the US Department of
Energy, supported by NASA through its Heliophysic Theory, Living With a
Star, and Supporting Research and Technology programs. L. F. and T.N.
acknowledges support by the UK STFC under rolling grant ST/F002637 and
by the European Commission through the SOLAIRE Network
(MTRNCT-2006-035484).
NR 45
TC 30
Z9 30
U1 0
U2 8
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 APR 20
PY 2009
VL 695
IS 2
BP 1151
EP 1162
DI 10.1088/0004-637X/695/2/1151
PG 12
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 430VS
UT WOS:000265018300034
ER
PT J
AU Vanzella, E
Giavalisco, M
Dickinson, M
Cristiani, S
Nonino, M
Kuntschner, H
Popesso, P
Rosati, P
Renzini, A
Stern, D
Cesarsky, C
Ferguson, HC
Fosbury, RAE
AF Vanzella, E.
Giavalisco, M.
Dickinson, M.
Cristiani, S.
Nonino, M.
Kuntschner, H.
Popesso, P.
Rosati, P.
Renzini, A.
Stern, D.
Cesarsky, C.
Ferguson, H. C.
Fosbury, R. A. E.
CA GOODS Team
TI SPECTROSCOPIC OBSERVATIONS OF LYMAN BREAK GALAXIES AT REDSHIFTS similar
to 4, 5, AND 6 IN THE GOODS-SOUTH FIELD
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE cosmology: observations; galaxies: distances and redshifts; galaxies:
evolution; galaxies: formation
ID HUBBLE-SPACE-TELESCOPE; STAR-FORMING GALAXIES; ORIGINS DEEP SURVEY;
LY-ALPHA EMISSION; REST-FRAME ULTRAVIOLET; FORMATION HISTORY; VLT/FORS2
SPECTROSCOPY; LUMINOSITY FUNCTIONS; STELLAR POPULATIONS; RADIATION
TRANSFER
AB We report on observations of Lyman break galaxies (LBGs) selected from the Great Observatories Origins Deep Survey at mean redshifts z similar to 4, 5, and 6 (B(435-), V(606-), and i(775)-band dropouts, respectively), obtained with the red-sensitive FORS2 spectrograph at the ESO VLT. This program has yielded spectroscopic identifications for 114 galaxies (similar to 60% of the targeted sample), of which 51 are at z similar to 4, 31 at z similar to 5, and 32 at z similar to 6. We demonstrate that the adopted selection criteria are effective, identifying galaxies at the expected redshift with minimal foreground contamination. Of the 10% interlopers, 83% turn out to be Galactic stars. Once selection effects are properly accounted for, the rest-frame ultraviolet (UV) spectra of the higher redshift LBGs appear to be similar to their counterparts at z similar to 3. As at z similar to 3, LBGs at z similar to 4 and z similar to 5 are observed with Ly alpha both in emission and in absorption; when in absorption, strong interstellar lines are also observed in the spectra. The stacked spectra of Lya absorbers and emitters also show that the former have redder UV spectra and stronger but narrower interstellar lines, a fact also observed at z similar to 2 and 3. At z similar to 6, sensitivity issues bias our sample toward galaxies with Ly alpha in emission; nevertheless, these spectra appear to be similar to their lower redshift counterparts. As in other studies at similar redshifts, we find clear evidence that brighter LBGs tend to have weaker Ly alpha emission lines. At fixed rest-frame UV luminosity, the equivalent width of the Ly alpha emission line is larger at higher redshifts. At all redshifts where the measurements can be reliably made, the redshift of the Ly alpha emission line turns out to be larger than that of the interstellar absorption lines (ISLs), with a median velocity difference Delta V similar to 400 km s(-1) at z similar to 4 and 5, consistent with results at lower redshifts. This shows that powerful, large-scale winds are common at high redshift. In general, there is no strong correlation between the morphology of the UV light and the spectroscopic properties. However, galaxies with deep ISLs and strong Ly alpha absorption appear to be more diffuse than galaxies with Ly alpha in emission.
C1 [Vanzella, E.; Cristiani, S.; Nonino, M.] INAF Osservatorio Astron Trieste, I-40131 Trieste, Italy.
[Giavalisco, M.] Univ Massachusetts, Dept Astron, Amherst, MA 01003 USA.
[Dickinson, M.] Natl Opt Astron Observ, Tucson, AZ 85726 USA.
[Cristiani, S.] Natl Inst Nucl Phys, Ist Nazl Fis Nucl, I-34127 Trieste, Italy.
[Kuntschner, H.; Fosbury, R. A. E.] ST EFC, D-85748 Garching, Germany.
[Popesso, P.; Rosati, P.; Cesarsky, C.] ESO, D-85748 Garching, Germany.
[Renzini, A.] INAF Osservatorio Astron Padova, I-35122 Padua, Italy.
[Stern, D.] CALTECH, JPL, Pasadena, CA 91109 USA.
[Ferguson, H. C.] STScI, Baltimore, MD 21218 USA.
RP Vanzella, E (reprint author), INAF Osservatorio Astron Trieste, Via GB Tiepolo 11, I-40131 Trieste, Italy.
OI Fosbury, Robert/0000-0001-9975-8003; Cristiani,
Stefano/0000-0002-2115-5234; Kuntschner, Harald/0000-0002-2768-1198
FU NASA; [ASI/COFIN I/016/07/0]; [PRIN INAF 2007]
FX We are grateful to the ESO staff in Paranal and Garching who greatly
helped in the development of this programme. We acknowledge financial
contribution from contract ASI/COFIN I/016/07/0 and PRIN INAF 2007 "A
Deep VLT and LBT view of the Early Universe." E. V. thanks STScI and
NOAO for hospitality during a visit in which this paper was conceived
and partially written. E. V. thanks F. Calura for useful discussions
about the dust properties of high-redshift galaxies. The work of D. S.
was carried out at Jet Propulsion Laboratory, California Institute of
Technology, under a contract with NASA.
NR 91
TC 134
Z9 134
U1 0
U2 4
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 APR 20
PY 2009
VL 695
IS 2
BP 1163
EP 1182
DI 10.1088/0004-637X/695/2/1163
PG 20
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 430VS
UT WOS:000265018300035
ER
PT J
AU Fukumura, K
Kazanas, D
Stephenson, G
AF Fukumura, Keigo
Kazanas, Demosthenes
Stephenson, Gordon
TI QUASI-PERIODIC OSCILLATIONS FROM RANDOM X-RAY BURSTS AROUND ROTATING
BLACK HOLES
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE accretion, accretion disks; black hole physics; stars: oscillations;
X-rays: galaxies
ID ADVECTION-DOMINATED ACCRETION; ENERGY EXTRACTION; GRO J1655-40;
BINARIES; PRECESSION; DISCOVERY; MODELS; PLASMA; FLOWS; DISK
AB We continue our earlier studies of quasi-periodic oscillations (QPOs) in the power spectra of accreting, rapidly rotating black holes that originate from the geometric "light echoes" of X-ray flares occurring within the black hole ergosphere. Our present work extends our previous treatment to three-dimensional photon emission and orbits to allow for arbitrary latitudes in the positions of the distant observers and the X-ray sources in place of the mainly equatorial positions and photon orbits of the earlier consideration. Following the trajectories of a large number of photons, we calculate the response functions of a given geometry and use them to produce model light curves which we subsequently analyze to compute their power spectra and autocorrelation functions. In the case of an optically thin environment, relevant to advection-dominated accretion flows, we consistently find QPOs at frequencies on the order of similar to kHz for stellar-mass black hole candidates, while on the order of similar to mHz for typical active galactic nuclei (similar to 10(7)M(circle dot)) for a wide range of viewing angles (30 degrees-80 degrees) from X-ray sources predominantly concentrated toward the equator within the ergosphere. As in our previous treatment, here too, the QPO signal is produced by the frame-dragging of the photons by the rapidly rotating black hole, which results in photon "bunches" separated by constant time lags, the result of multiple photon orbits around the hole. Our model predicts for various source/observer configurations the robust presence of a new class of QPOs, which is inevitably generic to a curved spacetime structure in rotating black hole systems.
C1 [Fukumura, Keigo] UMBC CRESST, Baltimore, MD 21250 USA.
[Fukumura, Keigo; Kazanas, Demosthenes] NASA, Goddard Space Flight Ctr, Astrophys Sci Div, Greenbelt, MD 20771 USA.
[Stephenson, Gordon] Univ Calif San Diego, La Jolla, CA 92093 USA.
RP Fukumura, K (reprint author), UMBC CRESST, Baltimore, MD 21250 USA.
EM Keigo.Fukumura@nasa.gov
NR 37
TC 5
Z9 5
U1 0
U2 1
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 APR 20
PY 2009
VL 695
IS 2
BP 1199
EP 1209
DI 10.1088/0004-637X/695/2/1199
PG 11
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 430VS
UT WOS:000265018300038
ER
PT J
AU Rawat, A
Wadadekar, Y
De Mello, D
AF Rawat, Abhishek
Wadadekar, Yogesh
De Mello, Dulia
TI REST-FRAME UV VERSUS OPTICAL MORPHOLOGIES OF GALAXIES USING SERSIC
PROFILE FITTING: THE IMPORTANCE OF MORPHOLOGICAL K-CORRECTION
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE galaxies: evolution; galaxies: formation; galaxies: statistics
ID STAR-FORMING GALAXIES; LYMAN-BREAK GALAXIES; ORIGINS DEEP SURVEY; MERGER
RATE; FIELD; Z-SIMILAR-TO-3; PARALLELS; REDSHIFTS; EVOLUTION
AB We show a comparison of the rest-frame UV morphologies of a sample of 162 intermediate-redshift (z(median) = 1.02) galaxies with their rest-frame optical morphologies. We select our sample from the deepest near-UV image obtained with the Hubble Space Telescope (HST) using the Wide Field Planetary Camera 2 (WFPC2; F300W) as part of the parallel observations of the Hubble Ultra Deep Field campaign overlapping with the HST/ACS Great Observatories Origins Deep Survey data set. We perform single-component Sersic fits in both WFPC2/F300W (rest-frame UV) and ACS/F850LP (rest-frame optical) bands and deduce that the Sersic index n is estimated to be smaller in the rest-frame UV compared to the rest-frame optical, leading to an overestimation of the number of merger candidates by similar to 40%-100% compared to the rest-frame optical depending upon the cutoff in n employed for identifying merger candidates. This effect seems to be dominated by galaxies with low values of n(F300W) <= 0.5 that have a value of n(F850LP) similar to 1.0. We argue that these objects are probably clumpy star-forming galaxies or minor mergers, both of which are essentially contaminants, if one is interested in identifying major mergers. In addition, we also find evidence that the axis ratio b/a is lower, i.e., ellipticity (1-b/a) is higher in rest-frame UV compared to the rest-frame optical. Moreover, we find that in the rest-frame UV, the number of high ellipticity (e >= 0.8) objects are higher by a factor of similar to 2.8 compared to the rest-frame optical. This indicates that the reported dominance of elongated morphologies among high-z Lyman Break Galaxies might just be a bias related to the use of rest-frame UV data sets in high-z studies.
C1 [Rawat, Abhishek] Inter Univ Ctr Astron & Astrophys, Pune 411007, Maharashtra, India.
[Wadadekar, Yogesh] Natl Ctr Radio Astrophys, Pune 411007, Maharashtra, India.
[De Mello, Dulia] NASA, Goddard Space Flight Ctr, Observat Cosmol Lab, Greenbelt, MD 20771 USA.
[De Mello, Dulia] Catholic Univ Amer, Washington, DC 20064 USA.
[De Mello, Dulia] Johns Hopkins Univ, Baltimore, MD 21218 USA.
RP Rawat, A (reprint author), Inter Univ Ctr Astron & Astrophys, Post Bag 4, Pune 411007, Maharashtra, India.
EM rawat@iucaa.ernet.in
NR 18
TC 7
Z9 7
U1 0
U2 1
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 APR 20
PY 2009
VL 695
IS 2
BP 1315
EP 1326
DI 10.1088/0004-637X/695/2/1315
PG 12
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 430VS
UT WOS:000265018300048
ER
PT J
AU Novak, G
Dotson, JL
Li, H
AF Novak, G.
Dotson, J. L.
Li, H.
TI DISPERSION OF OBSERVED POSITION ANGLES OF SUBMILLIMETER POLARIZATION IN
MOLECULAR CLOUDS
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE ISM: magnetic fields; polarization; stars: formation; submillimeter
ID MAGNETIC-FIELD STRENGTHS; FAR-INFRARED POLARIMETRY; STAR-FORMATION; DUST
EMISSION; DARK CLOUDS; TURBULENCE; CORES; MODELS; SPARO; HERTZ
AB One can estimate the characteristic magnetic field strength in Giant Molecular Clouds (GMCs) by comparing submillimeter polarimetric observations of these sources with simulated polarization maps developed using a range of different values for the assumed field strength. The point of comparison is the degree of order in the distribution of polarization position angles. In a recent paper by H. Li and collaborators, such a comparison was carried out using SPARO observations of two GMCs, and employing simulations by E. Ostriker and collaborators. Here, we re-examine this same question, using the same data set and the same simulations, but using an approach that differs in several respects. The most important difference is that we incorporate new, higher angular resolution observations for one of the clouds, obtained using the Hertz polarimeter. We conclude that the agreement between observations and simulations is best when the total magnetic energy (including both uniform and fluctuating field components) is at least as large as the turbulent kinetic energy.
C1 [Novak, G.] Northwestern Univ, Dept Phys & Astron, Evanston, IL 60208 USA.
[Dotson, J. L.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA.
[Li, H.] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA.
RP Novak, G (reprint author), Northwestern Univ, Dept Phys & Astron, Evanston, IL 60208 USA.
EM g-novak@northwestern.edu
FU SPARO [OPP-01-30389]; Hertz [AST-02-04886]; Caltech Submillimeter
Observatory [AST-05-40882]
FX This work has benefited from illuminating discussions with R. Hildebrand
and A. Lazarian. We are also grateful to E. Ostriker for providing the
unpublished simulation, to P. Calisse for operating SPARO, and to the N.
S. F. for supporting SPARO (Award OPP-01-30389 to Northwestern
University), Hertz (Award AST-02-04886 to the University of Chicago),
and the Caltech Submillimeter Observatory (Award AST-05-40882 to
Caltech).
NR 30
TC 16
Z9 16
U1 0
U2 4
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 APR 20
PY 2009
VL 695
IS 2
BP 1362
EP 1369
DI 10.1088/0004-637X/695/2/1362
PG 8
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 430VS
UT WOS:000265018300053
ER
PT J
AU Leggett, SK
Cushing, MC
Saumon, D
Marley, MS
Roellig, TL
Warren, SJ
Burningham, B
Jones, HRA
Kirkpatrick, JD
Lodieu, N
Lucas, PW
Mainzer, AK
Martin, EL
McCaughrean, MJ
Pinfield, DJ
Sloan, GC
Smart, RL
Tamura, M
Van Cleve, J
AF Leggett, S. K.
Cushing, Michael C.
Saumon, D.
Marley, M. S.
Roellig, T. L.
Warren, S. J.
Burningham, Ben
Jones, H. R. A.
Kirkpatrick, J. D.
Lodieu, N.
Lucas, P. W.
Mainzer, A. K.
Martin, E. L.
McCaughrean, M. J.
Pinfield, D. J.
Sloan, G. C.
Smart, R. L.
Tamura, M.
Van Cleve, J.
TI THE PHYSICAL PROPERTIES OF FOUR similar to 600 K T DWARFS
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE stars: atmospheres; stars: individual (ULAS J003402.77-005206.7, ULAS
J133553.45+113005.2, 2MASS J09393548-2448279, CFBD J005910.82-011401.3);
stars: low-mass, brown dwarfs
ID SPITZER-SPACE-TELESCOPE; EXOPLANET HOST STAR; DIGITAL SKY SURVEY; BROWN
DWARF; SPECTRAL CLASSIFICATION; CHEMICAL-EQUILIBRIUM; ULTRACOOL DWARFS;
GLIESE 229B; PHOTOMETRY; 2MASS
AB We present Spitzer 7.6-14.5 mu m spectra of ULAS J003402.77-005206.7 and ULAS J133553.45+113005.2, two T9 dwarfs with the latest spectral types currently known. We fit synthetic spectra and photometry to the near-through mid-infrared energy distributions of these dwarfs and that of the T8 dwarf 2MASS J09393548-2448279. We also analyze near-infrared data for another T9, CFBD J005910.82-011401.3. We find that the ratio of the mid-to near-infrared fluxes is very sensitive to effective temperature at these low temperatures, and that the 2.2 mu m and 4.5 mu m fluxes are sensitive to metallicity and gravity; increasing gravity has a similar effect to decreasing metallicity, and vice versa, and there is a degeneracy between these parameters. The 4.5 mu m and 10 mu m fluxes are also sensitive to vertical transport of gas through the atmosphere, which we find to be significant for these dwarfs. The full near-through mid-infrared spectral energy distribution allows us to constrain the effective temperature (K)/gravity (ms(2))/metallicity ([m/H] dex) of ULAS J0034-00 and ULAS J1335+11 to 550-600/100-300/0.0-0.3 and 500-550/100-300/0.0-0.3, respectively. These fits imply low masses and young ages for the dwarfs of 5-20 M(Jupiter) and 0.1-2 Gyr. The fits to 2MASS J0939-24 are in good agreement with the measured distance, the observational data, and the earlier T8 near-infrared spectral type if it is a slightly metal-poor 4-10 Gyr old system consisting of a 500 K and 700 K, similar to 25 M(Jupiter) and similar to 40 M(Jupiter), pair, although it is also possible that it is an identical pair of 600 K, 30 M(Jupiter), dwarfs. As no mid-infrared data are available for CFBD J0059-01 its properties are less well constrained; nevertheless it appears to be a 550-600 K dwarf with g = 300-2000 ms(-2) and [m/H] = 0-0.3 dex. These properties correspond to mass and age ranges of 10-50 M(Jupiter) and 0.5-10 Gyr for this dwarf.
C1 [Leggett, S. K.] Gemini Observ, Hilo, HI 96720 USA.
[Cushing, Michael C.] Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA.
[Saumon, D.] Los Alamos Natl Lab, Los Alamos, NM 87545 USA.
[Marley, M. S.; Roellig, T. L.] NASA, Ames Res Ctr, Moffett Field, CA 94305 USA.
[Warren, S. J.] Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2AZ, England.
[Burningham, Ben; Jones, H. R. A.; Lucas, P. W.; Pinfield, D. J.] Univ Hertfordshire, Sci & Technol Res Inst, Ctr Astrophys Res, Hatfield AL10 9AB, Herts, England.
[Kirkpatrick, J. D.] CALTECH, IPAC, Pasadena, CA 91125 USA.
[Lodieu, N.; Martin, E. L.] Inst Astrofis Canarias, E-38200 San Cristobal la Laguna, Spain.
[Mainzer, A. K.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
[Martin, E. L.] Univ Cent Florida, Dept Phys, Orlando, FL 32816 USA.
[McCaughrean, M. J.] Univ Exeter, Sch Phys, Exeter EX4 4QL, Devon, England.
[Sloan, G. C.] Cornell Univ, Dept Astron, Ithaca, NY 14853 USA.
[Smart, R. L.] Osserv Astron Torino, INAF, I-10025 Pino Torinese, TO, Italy.
[Tamura, M.] Natl Inst Nat Sci, Natl Astron Observ Japan, Mitaka, Tokyo 1818588, Japan.
[Van Cleve, J.] Ball Aerosp & Technol Corp, Boulder, CO 80301 USA.
RP Leggett, SK (reprint author), Gemini Observ, 670 N Aohoku Pl, Hilo, HI 96720 USA.
EM sleggett@gemini.edu
RI Marley, Mark/I-4704-2013;
OI Burningham, Ben/0000-0003-4600-5627; Smart, Richard/0000-0002-4424-4766;
Jones, Hugh/0000-0003-0433-3665
FU NASA; Association of Universities for Research in Astronomy, Inc;
Spanish Ministry of Science [AYA2007-67458]
FX This work is based on observations made with the Spitzer Space
Telescope, which is operated by the Jet Propulsion Laboratory,
California Institute of Technology under a contract with NASA. Support
for this work was provided by NASA through an award issued by
JPL/Caltech. S.K.L.'s research is supported by the Gemini Observatory,
which is operated by the Association of Universities for Research in
Astronomy, Inc., on behalf of the international Gemini partnership of
Argentina, Australia, Brazil, Canada, Chile, the United Kingdom, and the
United States of America. E.L.M.'s research is supported by The Spanish
Ministry of Science via project AYA2007-67458.
NR 45
TC 52
Z9 52
U1 0
U2 4
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 APR 20
PY 2009
VL 695
IS 2
BP 1517
EP 1526
DI 10.1088/0004-637X/695/2/1517
PG 10
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 430VS
UT WOS:000265018300066
ER
PT J
AU Ziurys, LM
Tenenbaum, ED
Pulliam, RL
Woolf, NJ
Milam, SN
AF Ziurys, L. M.
Tenenbaum, E. D.
Pulliam, R. L.
Woolf, N. J.
Milam, S. N.
TI CARBON CHEMISTRY IN THE ENVELOPE OF VY CANIS MAJORIS: IMPLICATIONS FOR
OXYGEN-RICH EVOLVED STARS
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE astrochemistry; circumstellar matter; radio lines: stars; stars: AGB and
post-AGB; supergiants
ID GIANT BRANCH STARS; MASS-LOSS-RATE; CIRCUMSTELLAR ENVELOPES; BEARING
MOLECULES; ROTATIONAL-EXCITATION; AGB STARS; O-RICH; SOLAR NEIGHBORHOOD;
LINE EMISSION; 1ST DETECTION
AB Observations of the carbon-bearing molecules CO, HCN, CS, HNC, CN, and HCO(+) have been conducted toward the circumstellar envelope of the oxygen-rich red supergiant star, VY Canis Majoris (VY CMa), using the Arizona Radio Observatory (ARO). CO and HCN were also observed toward the O-rich shells of NML Cyg, TX Cam, IK Tau, and W Hya. Rotational transitions of these species at 1 mm, 0.8 mm, and 0.4 mm were measured with the ARO Submillimeter Telescope, including the J = 6 -> 5 line of CO at 691 GHz toward TX Cam and W Hya. The ARO 12 m was used for 2 mm and 3 mm observations. Four transitions were observed for HCO+ in VY CMa, the first definitive identification of this ion in a circumstellar envelope. Molecular line profiles from VY CMa are complex, indicating three separate outflows: a roughly spherical flow and separate red- and blueshifted winds, as suggested by earlier observations. Spectra from the other sources appear to trace a single outflow component. The line data were modeled with a radiative transfer code to establish molecular abundances relative to H(2) and source distributions. Abundances for CO derived for these objects vary over an order of magnitude, f similar to 0.4-5 x 10(-4), with the lower values corresponding to the supergiants. For HCN, a similar range in abundance is found (f similar to 0.9- 9 x 10(-6)), with no obvious dependence on the mass-loss rate. In VY CMa, HCO+ is present in all three outflows with f similar to 0.4-1.6 x 10(-8) and a spatial extent similar to that of CO. HNC is found only in the red- and blueshifted components with [HCN]/[ HNC] similar to 150-190, while [CN]/[HCN] similar to 0.01 in the spherical flow. All three velocity components are traced in CS, which has a confined spatial distribution and f similar to 2-6 x 10(-7). These observations suggest that carbon-bearing molecules in O-rich shells are produced by a combination of photospheric shocks and photochemistry. Shocks may play a more prominent role in the supergiants because of their macroturbulent velocities.
C1 [Ziurys, L. M.; Tenenbaum, E. D.; Pulliam, R. L.; Woolf, N. J.] Univ Arizona, Dept Astron, Tucson, AZ 85721 USA.
[Ziurys, L. M.; Tenenbaum, E. D.; Pulliam, R. L.; Woolf, N. J.] Univ Arizona, Steward Observ, Tucson, AZ 85721 USA.
[Ziurys, L. M.; Tenenbaum, E. D.; Pulliam, R. L.] Univ Arizona, Dept Chem, Tucson, AZ 85721 USA.
[Ziurys, L. M.] Univ Arizona, Arizona Radio Observ, Tucson, AZ 85721 USA.
[Milam, S. N.] NASA, Ames Res Ctr, SETI Inst, Moffett Field, CA 94035 USA.
RP Ziurys, LM (reprint author), Univ Arizona, Dept Astron, 933 N Cherry Ave, Tucson, AZ 85721 USA.
EM lziurys@as.arizona.edu; emilyt@as.arizona.edu;
rpulliam@email.arizona.edu; nwoolf@as.arizona.edu;
Stefanie.N.Milam@nasa.gov
RI Milam, Stefanie/D-1092-2012
OI Milam, Stefanie/0000-0001-7694-4129
FU NSF [AST-06-07803]; NASA Astrobiology Institute [CAN-02-0SS02]
FX This research is supported by NSF Grant AST-06-07803 and the NASA
Astrobiology Institute under cooperative agreement CAN-02-0SS02 issued
through the Office of Space Science. E. D. T. thanks the NSF for her
graduate fellowship. The authors also thank the staff of the ARO for
their assistance, and Eugene Lauria for his efforts in providing the
newARO 0.4 mm receiver.
NR 56
TC 30
Z9 30
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 APR 20
PY 2009
VL 695
IS 2
BP 1604
EP 1613
DI 10.1088/0004-637X/695/2/1604
PG 10
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 430VS
UT WOS:000265018300074
ER
PT J
AU Dodson-Robinson, SE
Bodenheimer, P
AF Dodson-Robinson, Sarah E.
Bodenheimer, Peter
TI DISCOVERING THE GROWTH HISTORIES OF EXOPLANETS: THE SATURN ANALOG HD
149026b
SO ASTROPHYSICAL JOURNAL LETTERS
LA English
DT Article
DE methods: analytical; planetary systems: formation; planetary systems:
protoplanetary disks; planets and satellites: formation
ID TRANSITING EXTRASOLAR PLANETS; GIANT PLANETS; CORE ACCRETION;
PROTOSTELLAR DISKS; SOLAR NEBULA; JUPITER; MIGRATION; MODELS; STARS; GAS
AB The transiting "hot Saturn" HD149026b, which has the highest mean density of any confirmed planet in the Neptune Jupiter mass range, has challenged theories of planet formation since its discovery in 2005. Previous investigations could not explain the origin of the planet's 45-110 Earth-mass solid core without invoking catastrophes such as gas giant collisions or heavy planetesimal bombardment launched by neighboring planets. Here we show that HD 149026b's large core can be successfully explained by the standard core accretion theory of planet formation. The keys to our reconstruction of HD 149026b are (1) applying a model of the solar nebula to describe the protoplanet nursery, (2) placing the planet initially on a long-period orbit at Saturn's heliocentric distance of 9.5 AU, and (3) adjusting the solid mass in the HD 149026 disk to twice that of the solar nebula in accordance with the star's heavy element enrichment. We show that the planet's migration into its current orbit at 0.042 AU is consistent with our formation model. Our study of HD 149026b demonstrates that it is possible to discover the growth history of any planet with a well-defined core mass that orbits a solar-type star.
C1 [Dodson-Robinson, Sarah E.] CALTECH, Exoplanet Sci Inst, NASA, Pasadena, CA 91125 USA.
[Bodenheimer, Peter] Univ Calif Santa Cruz, Lick Observ, UCO, Santa Cruz, CA 95064 USA.
RP Dodson-Robinson, SE (reprint author), CALTECH, Exoplanet Sci Inst, NASA, 770 S Wilson Ave, Pasadena, CA 91125 USA.
EM sdr@ipac.caltech.edu
FU NASA Origins [NNX08AH82G]
FX Support for S. D. R's work was provided by NASA through the Spitzer
Space Telescope Fellowship Program. P. B. received support from the NASA
Origins Grant NNX08AH82G. The authors thank Chas Beichman for helpful
comments.
NR 39
TC 9
Z9 9
U1 0
U2 2
PU IOP PUBLISHING LTD
PI BRISTOL
PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND
J9 ASTROPHYS J LETT
JI Astrophys. J. Lett.
PD APR 20
PY 2009
VL 695
IS 2
BP L159
EP L162
DI 10.1088/0004-637X/695/2/L159
PG 4
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 428TE
UT WOS:000264872100008
ER
PT J
AU Gosling, JT
McComas, DJ
Roberts, DA
Skoug, RM
AF Gosling, J. T.
McComas, D. J.
Roberts, D. A.
Skoug, R. M.
TI A ONE-SIDED ASPECT OF ALFVENIC FLUCTUATIONS IN THE SOLAR WIND
SO ASTROPHYSICAL JOURNAL LETTERS
LA English
DT Article
DE magnetic fields; plasmas; solar wind; turbulence; waves
ID TURBULENCE; WAVES; RECONNECTION; MODEL
AB Using Advanced Composition Explorer (ACE) 64 s data at 1 AU we find that Alfvenic fluctuations propagating outward from the Sun along the magnetic field, B, in the solar wind often produce one-sided variations in one of the equatorial components of Band velocity, V. This is a natural consequence of the fact that the Alfvenic fluctuations are transverse fluctuations in which |B| remains nearly constant. Thus, fluctuations in the field component that defines the underlying background field direction are always relative to a base value rather than to an average value. This suggests that conclusions derived from statistical analyses of fluctuations in the solar wind that assume the fluctuations in all field components are relative to average values need to be re-examined. We also find that discrete, sunward-propagating Alfvenic fluctuations or rotational discontinuities are extremely rare in the pristine solar wind; thus far we have identified such discrete events in ACE data only in association with events identified as magnetic reconnection exhausts and/or in association with backstreaming ions from reverse shocks, including Earth's bow shock.
C1 [Gosling, J. T.] Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80303 USA.
[McComas, D. J.] SW Res Inst, San Antonio, TX 78228 USA.
[Roberts, D. A.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
[Skoug, R. M.] Los Alamos Natl Lab, Los Alamos, NM 87545 USA.
RP Gosling, JT (reprint author), Univ Colorado, Atmospher & Space Phys Lab, 1234 Innovat Dr, Boulder, CO 80303 USA.
EM jack.gosling@lasp.colorado.edu
FU NASA [NNG06GC27G]; NASA/ACE program
FX J. G. thanks A. Balogh, J. Borovsky, T. Horbury, B. Matthaeus, M.
Neugebauer, C. Smith, and M. Velli, for a number of stimulating
conversations on one or more of the topics of this paper, C. Smith for
use of the magnetometer data, and M. Desai for providing energetic
particle observations. This work has been supported by NASA grant
NNG06GC27G and the SWEPAM portion of the NASA/ACE program.
NR 19
TC 23
Z9 24
U1 0
U2 4
PU IOP PUBLISHING LTD
PI BRISTOL
PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND
J9 ASTROPHYS J LETT
JI Astrophys. J. Lett.
PD APR 20
PY 2009
VL 695
IS 2
BP L213
EP L216
DI 10.1088/0004-637X/695/2/L213
PG 4
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 428TE
UT WOS:000264872100020
ER
PT J
AU Reynolds, SP
Borkowski, KJ
Green, DA
Hwang, U
Harrus, I
Petre, R
AF Reynolds, Stephen P.
Borkowski, Kazimierz J.
Green, David A.
Hwang, Una
Harrus, Ilana
Petre, Robert
TI X-RAY SPECTRAL VARIATIONS IN THE YOUNGEST GALACTIC SUPERNOVA REMNANT
G1.9+0.3
SO ASTROPHYSICAL JOURNAL LETTERS
LA English
DT Article
DE ISM: individual (G1.9+0.3); supernova remnants; X-rays: ISM
ID SHOCK ACCELERATION; HIGH-ENERGY; GRAINS
AB The discovery of the youngest Galactic supernova remnant (SNR) G1.9+0.3 has allowed a look at a stage of SNR evolution never before observed. We analyze the 50 ks Chandra observation with particular regard to spectral variations. The very high column density (N(H) similar to 6 x 10(22) cm(-2)) implies that dust scattering is important, and we use a simple scattering model in our spectral analysis. The integrated X-ray spectrum of G1.9+0.3 is well described by synchrotron emission from a power-law electron distribution with an exponential cutoff. Using our measured radio flux and including scattering effects, we find a rolloff frequency of 5.4(3.0, 10.2) x 10(17) Hz (h nu(roll) = 2.2 keV). Including scattering in a two-region model gives lower values of nu(roll) by over a factor of 2. Dividing G1.9+0.3 into six regions, we find a systematic pattern in which spectra are hardest (highest nu(roll)) in the bright southeast and northwest limbs of the shell. They steepen as one moves around the shell or into the interior. The extensions beyond the bright parts of the shell have the hardest spectra of all. We interpret the results in terms of dependence of shock acceleration properties on the obliquity angle theta(Bn) between the shock velocity and a fairly uniform upstream magnetic field. This interpretation probably requires a Type Ia event. If electron acceleration is limited by synchrotron losses, the spectral variations require obliquity-dependence of the acceleration rate independent of the magnetic-field strength.
C1 [Reynolds, Stephen P.; Borkowski, Kazimierz J.] N Carolina State Univ, Dept Phys, Raleigh, NC 27695 USA.
[Green, David A.] Univ Cambridge, Cavendish Lab, Cambridge CB3 0HE, England.
[Hwang, Una; Harrus, Ilana; Petre, Robert] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
RP Reynolds, SP (reprint author), N Carolina State Univ, Dept Phys, Raleigh, NC 27695 USA.
EM stephen_reynolds@ncsu.edu
RI Green, David/E-9609-2010
OI Green, David/0000-0003-3189-9998
FU NASA through Chandra General Observer Program [GO6- 7059X]
FX This work was supported by NASA through Chandra General Observer Program
grant GO6- 7059X. We thank A. Patil, D. Huard, and C. Fonnesbeck for
creating and making available the PyMC package.
NR 15
TC 21
Z9 21
U1 0
U2 2
PU IOP PUBLISHING LTD
PI BRISTOL
PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND
SN 2041-8205
J9 ASTROPHYS J LETT
JI Astrophys. J. Lett.
PD APR 20
PY 2009
VL 695
IS 2
BP L149
EP L153
DI 10.1088/0004-637X/695/2/L149
PG 5
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 428TE
UT WOS:000264872100006
ER
PT J
AU Gordley, LL
Thompson, E
McHugh, M
Remsberg, E
Russell, J
Magill, B
AF Gordley, Larry L.
Thompson, Earl
McHugh, Martin
Remsberg, Ellis
Russell, James, III
Magill, Brian
TI Accuracy of atmospheric trends inferred from the Halogen Occultation
Experiment data
SO JOURNAL OF APPLIED REMOTE SENSING
LA English
DT Article
DE solar occultation; atmospheric trends; satellite remote sensing;
radiometry
ID STRATOSPHERIC WATER-VAPOR; UARS PLATFORM; VALIDATION; OZONE; PROFILES;
QUALITY
AB The Halogen Occultation Experiment (HALOE) operated in orbit for over 14 years, providing high quality measurements from the upper troposphere into the lower thermosphere. Since the quality of this data set depended on the long-term stability of the instrument, a series of analysis tests were designed to routinely monitor instrument performance. These tests evaluated possible changes in the gas cells, electronic gains, optical performance, and signal temperature dependencies. The gas cell stability was determined from an analysis of the Doppler shift signature in retrieved mixing ratios. Electronic gain stability was determined by instrument scans of the solar disk, each with different balance settings. Optical and tracking performance was also determined from solar scan data. The only statistically significant changes detected were: 1. a small methane gas cell change, causing less than 0.5% per decade change in retrieved methane, and 2. a small optical alignment change in the HF channel that only affects HF results below 25 kilometers. These detailed analyses indicate that the HALOE instrument remained stable throughout the mission, adding confidence to the long-term atmospheric trends deduced from HALOE products.
C1 [Gordley, Larry L.; Thompson, Earl; McHugh, Martin] GATS Inc, Newport News, VA 23606 USA.
[Remsberg, Ellis] NASA, Langley Res Ctr, Atmospher Sci Directorate, Hampton, VA 23681 USA.
[Russell, James, III] Hampton Univ, Ctr Atmospher Sci, Hampton, VA 23668 USA.
[Magill, Brian] SSAI, Hampton, VA 23666 USA.
RP Gordley, LL (reprint author), GATS Inc, 11864 Canon Blvd,Suite 101, Newport News, VA 23606 USA.
EM l.l.gordley@gats-inc.com; r.e.thompson@gats-inc.com;
m.j.mchugh@gats-inc.com; e.e.remsberg@larc.nasa.gov;
james.russell@hamptonu.edu; brian_magill@ssaihq.com
FU NASA [NAS1-02058, NNG04GE42G]
FX We would like to thank Jeff Tabor of SAIC, Inc. for supplying us with
the DAC data and would also like to thank Janet Daniels of SAIC and John
Wells of NASA Langley for helpful discussions and suggestions. This work
was supported by NASA Contract No. NAS1-02058 and NASA Grant No.
NNG04GE42G.
NR 25
TC 8
Z9 8
U1 0
U2 1
PU SPIE-SOC PHOTOPTICAL INSTRUMENTATION ENGINEERS
PI BELLINGHAM
PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98225 USA
SN 1931-3195
J9 J APPL REMOTE SENS
JI J. Appl. Remote Sens.
PD APR 20
PY 2009
VL 3
AR 033526
DI 10.1117/1.3131722
PG 24
WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic
Technology
SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science &
Photographic Technology
GA 520WD
UT WOS:000271879300001
ER
PT J
AU Wu, DL
Austin, RT
Deng, M
Durden, SL
Heymsfield, AJ
Jiang, JH
Lambert, A
Li, JL
Livesey, NJ
McFarquhar, GM
Pittman, JV
Stephens, GL
Tanelli, S
Vane, DG
Waliser, DE
AF Wu, D. L.
Austin, R. T.
Deng, M.
Durden, S. L.
Heymsfield, A. J.
Jiang, J. H.
Lambert, A.
Li, J. -L.
Livesey, N. J.
McFarquhar, G. M.
Pittman, J. V.
Stephens, G. L.
Tanelli, S.
Vane, D. G.
Waliser, D. E.
TI Comparisons of global cloud ice from MLS, CloudSat, and correlative data
sets
SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
LA English
DT Article
ID MILLIMETER-WAVE RADAR; VISIBLE OPTICAL DEPTH; PACIFIC WARM POOL;
WATER-CONTENT; EOS MLS; RADIATIVE-TRANSFER; PROFILING RADAR; CIRRUS
CLOUDS; RETRIEVALS; SATELLITE
AB Aura Microwave Limb Sounder (MLS) version 2.2 (V2.2) and CloudSat R04 (release 4) ice water content (IWC) and partial-column ice water path (pIWP) measurements are analyzed and compared to other correlative data sets. The MLS IWC, representing an average over similar to 300 x 7 x 4 km(3) volume, is retrieved at 215-268 hPa with precision varying between 0.06 and 1 mg/m(3). The MLS pIWP products, representing the partial columns over similar to 100 x 7 km(2) area with the bottom at similar to 8, similar to 6, and similar to 11 km for 115, 240, and 640 GHz, have estimated precisions of 5, 1.5, and 0.8 g/m(2), respectively. CloudSat, on the other hand, shows a minimum detectable sensitivity of -31 dBZ in the reflectivity measurement at 94 GHz. CloudSat IWC is an average over similar to 1.8 x 1.4 x 0.5 km(3) volume, and its precision varies from 0.4 mg/m(3) at 8 km to 1.6 mg/m(3) at 12 km. The estimated single-profile precision for CloudSat IWP is similar to 9 g/m(2). However, these measurements are associated with relatively large systematic error, mostly due to uncertainties in the retrieval assumptions about microphysics, which lead to relatively poor accuracy compared to measurement precision. To characterize systematic differences among various observations and those derived from models, we employ the normalized probability density function (pdf) in the comparisons. CloudSat IWC shows generally consistent slopes of pdf distribution with in situ observations, particularly at similar to 12 km where the in situ data come mostly from long-leg flights. Despite similar IWC morphology found between MLS and CloudSat observations, CloudSat R04 IWC retrieval is higher compared to MLS, especially at 14-17 km where the MLS technique is not limited by sensitivity saturation. The MLS and CloudSat IWC pdf's agree well in the overlapped sensitivity range with relative difference <50%, but the difference appears to increase with IWC. MLS and CloudSat cloud ice measurements are compared with other data sets in terms of monthly map and pdf. Comparisons with European Center for Medium range Weather Forecasting (ECMWF) analyses show that grid box averages of monthly ECMWF IWC are much smaller (by similar to 5 x and similar to 20 x) than the same MLS and CloudSat averages. Comparisons of pIWP data from CloudSat and passive sensors reveal large uncertainties associated with passive techniques, such as penetration depth and sensitivity limitation. In particular, retrievals from Moderate Resolution Imaging Spectroradiometer (MODIS) and Advanced Microwave Sounding Unit-B (AMSU-B) differ largely in IWP pdf from the CloudSat R04 retrieval, showing CloudSat values generally lower (by similar to 5 x and similar to 8 x, respectively) at IWP = 10-500 g/m(2) but higher at IWP > 500 g/m(2).
C1 [Wu, D. L.; Durden, S. L.; Jiang, J. H.; Lambert, A.; Li, J. -L.; Livesey, N. J.; Tanelli, S.; Vane, D. G.; Waliser, D. E.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
[Austin, R. T.; Stephens, G. L.] Colorado State Univ, Dept Atmospher Sci, Ft Collins, CO 80523 USA.
[Deng, M.] Univ Wyoming, Dept Atmospher Sci, Laramie, WY 82071 USA.
[Heymsfield, A. J.] Natl Ctr Atmospher Res, Boulder, CO 80307 USA.
[McFarquhar, G. M.] Univ Illinois, Dept Atmospher Sci, Urbana, IL 61820 USA.
[Pittman, J. V.] NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA.
RP Wu, DL (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA.
EM dong.l.wu.@jpl.nasa.gov
RI Heymsfield, Andrew/E-7340-2011; Wu, Dong/D-5375-2012;
OI McFarquhar, Greg/0000-0003-0950-0135
NR 65
TC 45
Z9 46
U1 0
U2 13
PU AMER GEOPHYSICAL UNION
PI WASHINGTON
PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA
SN 2169-897X
J9 J GEOPHYS RES-ATMOS
JI J. Geophys. Res.-Atmos.
PD APR 18
PY 2009
VL 114
AR D00A24
DI 10.1029/2008JD009946
PG 20
WC Meteorology & Atmospheric Sciences
SC Meteorology & Atmospheric Sciences
GA 435FO
UT WOS:000265329500001
ER
PT J
AU Birn, J
Hesse, M
Schindler, K
Zaharia, S
AF Birn, J.
Hesse, M.
Schindler, K.
Zaharia, S.
TI Role of entropy in magnetotail dynamics
SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
LA English
DT Article
ID COLLISIONLESS MAGNETIC RECONNECTION; THIN CURRENT SHEETS; PLASMA SHEET;
EARTHS MAGNETOTAIL; ELECTRON DISSIPATION; FLUX TUBES; CONVECTION;
BUBBLES; BALANCE; FLOWS
AB The role of entropy conservation and loss in magnetotail dynamics, particularly in relation to substorm phases, is discussed on the basis of MHD theory and simulations, using comparisons with particle-in-cell (PIC) simulations for validation. Entropy conservation appears to be a crucial element leading to the formation of thin embedded current sheets in the late substorm growth phase and the potential loss of equilibrium. Entropy conservation also governs the accessibility of final states of evolution and the amount of energy that may be released. Entropy loss (in the form of plasmoids) is essential in the earthward transport of flux tubes (bubbles, bursty bulk flows). Entropy loss also changes the tail stability properties and may render ballooning modes unstable and thus contribute to cross-tail variability. We illustrate these effects through results from theory and simulations.
C1 [Birn, J.; Zaharia, S.] Los Alamos Natl Lab, Space Sci & Applicat Grp, Los Alamos, NM 87545 USA.
[Hesse, M.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
[Schindler, K.] Ruhr Univ Bochum, Inst Theoret Phys, D-44780 Bochum, Germany.
RP Birn, J (reprint author), Los Alamos Natl Lab, Space Sci & Applicat Grp, POB 1663, Los Alamos, NM 87545 USA.
EM 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
FU NASA Goddard Space Flight Center; NASA's Heliophysics Theory Program
FX This work was performed under the auspices of the U. S. Department of
Energy, supported by a grant from NASA Goddard Space Flight Center and
by NASA's Heliophysics Theory Program.; Wolfgang Baumjohann thanks the
reviewers for their assistance in evaluating this paper.
NR 38
TC 41
Z9 42
U1 0
U2 5
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 APR 18
PY 2009
VL 114
AR A00D03
DI 10.1029/2008JA014015
PG 11
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 435GN
UT WOS:000265332200005
ER
PT J
AU Michael, M
Tripathi, SN
Borucki, WJ
Whitten, RC
AF Michael, Marykutty
Tripathi, Sachchida Nand
Borucki, W. J.
Whitten, R. C.
TI Highly charged cloud particles in the atmosphere of Venus
SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
LA English
DT Article
ID AEROSOL ATTACHMENT COEFFICIENTS; COSMIC-RAY IONIZATION;
ELECTRICAL-CONDUCTIVITY; PLANETARY-ATMOSPHERES; NEGATIVE-IONS; NIGHT
SIDE; MODEL; MICROPHYSICS; DUST; IONOSPHERE
AB The accumulation of charges on cloud particles by the charge transfer of ions and attachment of electrons in the atmosphere of Venus is investigated in the present work. Three cloud layers between 45 and 70 km exist in the atmosphere of Venus. Ions and electrons are produced by the interaction of galactic cosmic rays with the neutral molecules. Ion to particle and electron to particle attachment coefficients are calculated. The charge balance equations include ion-ion recombination, ion-electron recombination, electron attachment to neutrals, electron detachment from negative ions, and attachment of electron and charge transfer from ions to particles. It is found that the ion concentrations are reduced by a maximum of a factor of 5 by charging of the particles, while the earlier studies showed a maximum reduction of about an order of magnitude due to the differences in the surface area of the particles. A similar result is observed in the calculation of electrical conductivity. Both monodisperse and polydisperse distribution of particles are considered. The conductivity was reduced by a factor of 3 when using the monodisperse distribution of particles, while the maximum reduction observed was a factor of 2 when using the polydisperse distribution. This result implies that the monodisperse particle distribution overestimates the effect of particles on the atmospheric conductivity. The ratio of negative to positive charges is found to be very large in the middle and upper cloud layers. The low abundance of the aerosols and high conductivity of the atmosphere appear to rule out lightning activity in the 40 to 70 km altitude region.
C1 [Michael, Marykutty; Tripathi, Sachchida Nand] Indian Inst Technol, Dept Civil Engn, Kanpur 208016, Uttar Pradesh, India.
[Borucki, W. J.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA.
[Whitten, R. C.] SETI Res Inst, Mountain View, CA 94043 USA.
RP Michael, M (reprint author), Indian Inst Technol, Dept Civil Engn, Kanpur 208016, Uttar Pradesh, India.
EM snt@iitk.ac.in
RI Tripathi, Sachchida/J-4840-2016
NR 64
TC 17
Z9 17
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-PLANET
JI J. Geophys. Res.-Planets
PD APR 17
PY 2009
VL 114
AR E04008
DI 10.1029/2008JE003258
PG 18
WC Geochemistry & Geophysics
SC Geochemistry & Geophysics
GA 435GF
UT WOS:000265331200001
ER
PT J
AU Hakkinen, S
Rhines, PB
AF Hakkinen, Sirpa
Rhines, Peter B.
TI Shifting surface currents in the northern North Atlantic Ocean
SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
LA English
DT Article
ID SUBPOLAR GYRE; THERMOHALINE CIRCULATION; KINETIC-ENERGY; LABRADOR SEA;
NORDIC SEAS; VARIABILITY; WATER; OSCILLATION; ALTIMETRY; PATHWAYS
AB Analysis of surface drifter tracks in the North Atlantic Ocean from the time period 1990 to 2007 provides evidence that warm subtropical waters have recently increased their penetration toward the Nordic seas. Prior to 2000, the warm water branches of the North Atlantic Current fed by the Gulf Stream turned southeastward in the eastern North Atlantic. Since 2001, these paths have shifted toward the Rockall Trough, through which the most saline North Atlantic waters pass to the Nordic seas. These surface drifters are able to overcome the Ekman drift, which would force them southward under the westerly winds dominating the subpolar Atlantic, yet the changes in path cannot be accounted for by changes in Ekman drift. Eddy kinetic energy from satellite altimetry shows increased energy along the shifted drifter pathways across the Mid-Atlantic Ridge since 2001. These near-surface changes have occurred during continual weakening of the North Atlantic subpolar gyre, as seen by altimetry. They are also consistent with the observed increase in temperature and salinity of the waters flowing northward into the Nordic seas. These findings suggest the changes in the vertical structure of the northern North Atlantic Ocean, its dynamics, and exchanges with the higher latitudes. Wind stress and its curl changes are discussed as a possible forcing of the changes in the pathways of the subtropical waters.
C1 [Hakkinen, Sirpa] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
[Rhines, Peter B.] Univ Washington, Sch Oceanog, Seattle, WA 98195 USA.
RP Hakkinen, S (reprint author), NASA, Goddard Space Flight Ctr, Code 614-2, Greenbelt, MD 20771 USA.
EM sirpa.hakkinen@nasa.gov
RI Hakkinen, Sirpa/E-1461-2012
FU NASA; OSTST Science Team
FX S. H. gratefully acknowledges the support from NASA Headquarters
Physical Oceanography Program for this work. P. B. R. is supported by
NASA through the OSTST Science Team. We thank Denise Worthen for the
invaluable technical assistance in data set analysis and graphics.
NR 40
TC 85
Z9 86
U1 4
U2 35
PU AMER GEOPHYSICAL UNION
PI WASHINGTON
PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA
SN 0148-0227
J9 J GEOPHYS RES-OCEANS
JI J. Geophys. Res.-Oceans
PD APR 16
PY 2009
VL 114
AR C04005
DI 10.1029/2008JC004883
PG 12
WC Oceanography
SC Oceanography
GA 435FV
UT WOS:000265330200001
ER
PT J
AU Zhou, D
Semones, E
Gaza, R
Johnson, S
Zapp, N
Lee, K
George, T
AF Zhou, D.
Semones, E.
Gaza, R.
Johnson, S.
Zapp, N.
Lee, K.
George, T.
TI Radiation measured during ISS-Expedition 13 with different dosimeters
SO ADVANCES IN SPACE RESEARCH
LA English
DT Article
DE Space radiation; Cosmic rays; Active and passive dosimeters; LET spectra
ID LOW-EARTH-ORBIT; HIGH-LET RADIATION; CR-39 DETECTORS; TRACK DETECTORS;
DOSE-EQUIVALENT; COSMIC-RAYS; SPECTRA; ETCH
AB Radiation in low Earth orbit (LEO) is mainly composed of galactic cosmic rays (GCR), solar energetic particles and particles in SAA (South Atlantic Anomaly). The biological impact of space radiation to astronauts depends strongly on the particles' linear energy transfer (LET) and is dominated by high LET radiation. It is important to measure the LET spectrum for the space radiation field and to investigate the influence of radiation oil astronauts. At present, the preferred active dosimeters sensitive to all LET are the tissue equivalent proportional counter (TEPC) and the silicon detectors in various configurations; the preferred passive dosimeters are CR-39 plastic nuclear track detectors (PNTDs) sensitive to high LET and thermoluminescence dosimeters (TLDs) as well as optically stimulated luminescence dosimeters (OSLDs) sensitive to low LET. The TEPC, CR-39 PNTDs, TLDs and OSLDs were used to investigate the radiation field for the ISS mission Expedition 13 (ISS-12S) in LEO. LET spectra and radiation quantities (fluence, absorbed dose, dose equivalent and quality factor) were measured for the space mission with different dosimeters. This paper introduces the role of high LET radiation in radiobiology, the operational principles for the different dosimeters, the LET spectrum method using CR-39 detectors, the method to combine the results measured with TLDs/OSLDs and CR-39 PNTDs, and presents the LET spectra and the radiation quantities measured and combined. Published by Elsevier Ltd on behalf of COSPAR.
C1 [Zhou, D.; Semones, E.; Gaza, R.; Johnson, S.; Zapp, N.; Lee, K.; George, T.] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA.
[Zhou, D.; Gaza, R.] Univ Space Res Assoc, Houston, TX 77058 USA.
RP Zhou, D (reprint author), NASA, Lyndon B Johnson Space Ctr, 2101 Nasa Pkwy, Houston, TX 77058 USA.
EM dazhuang.zhou-1@nasa.gov
NR 35
TC 12
Z9 14
U1 0
U2 5
PU ELSEVIER SCI LTD
PI OXFORD
PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND
SN 0273-1177
J9 ADV SPACE RES
JI Adv. Space Res.
PD APR 15
PY 2009
VL 43
IS 8
BP 1212
EP 1219
DI 10.1016/j.asr.2009.02.003
PG 8
WC Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology &
Atmospheric Sciences
SC Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences
GA 438OV
UT WOS:000265565900006
ER
PT J
AU Bamsey, M
Berinstain, A
Auclair, S
Battler, M
Binsted, K
Bywaters, K
Harris, J
Kobrick, R
Mckay, C
AF Bamsey, M.
Berinstain, A.
Auclair, S.
Battler, M.
Binsted, K.
Bywaters, K.
Harris, J.
Kobrick, R.
McKay, C.
TI Four-month Moon and Mars crew water utilization study conducted at the
Flashline Mars Arctic Research Station, Devon Island, Nunavut
SO ADVANCES IN SPACE RESEARCH
LA English
DT Article
DE Space analogue studies; Space life support; Water utilization; Moon/Mars
exploration
AB A categorized water usage study was undertaken at the Flashline Mars Arctic Research Station on Devon Island, Nunavut in the High Canadian Arctic. This study was conducted as part of a long duration four-month Mars mission simulation during the summer of 2007. The study determined that the crew of seven averaged 82.07 L/day over the expedition (standard deviation 22.58 L/day). The study also incorporated a Mars Time Study phase which determined that an average of 12.12 L/sol of water was required for each crewmember. Drinking, food preparation, hand/face, oral, dish wash, clothes wash, shower, shaving, cleaning, engineering, science, plant growth and medical water were each individually monitored throughout the detailed study phases. It was determined that implementing the monitoring program itself resulted in an approximate water savings of 1.5 L/day per crewmember. The seven person crew averaged 202 distinct water draws a day (standard deviation 34) with high water use periods focusing around meal times. No statistically significant correlation was established between total water use and EVA or exercise duration. Study results suggest that current crew water utilization estimates for long duration planetary surface stays are more than two times greater than that required. Crown copyright (C) 2009 Published by Elsevier Ltd. on behalf of COSPAR. All rights reserved.
C1 [Bamsey, M.; Berinstain, A.] Univ Guelph, Dept Environm Biol, Guelph, ON N1G 2W1, Canada.
[Berinstain, A.] Canadian Space Agcy, Longueuil, PQ J3Y 8Y9, Canada.
[Auclair, S.; Battler, M.] Univ Western Ontario, Dept Earth Sci, London, ON N6A 5B7, Canada.
[Binsted, K.] Univ Hawaii, NASA, Astrobiol Inst, Informat & Comp Sci Dept, Honolulu, HI 96744 USA.
[Bywaters, K.] Calif State Univ San Marcos, San Marcos, CA 92096 USA.
[Harris, J.] Austin Community Coll, Dept Comp Informat Syst, Austin, TX 78724 USA.
[Kobrick, R.] Univ Colorado, Dept Aerosp Engn Sci, Boulder, CO 80303 USA.
[McKay, C.] NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94035 USA.
RP Bamsey, M (reprint author), Univ Guelph, Dept Environm Biol, 50 Stone Rd E, Guelph, ON N1G 2W1, Canada.
EM mbamsey@uoguelph.ca
RI Battler, Melissa/N-2591-2014
FU Polar Continental Shelf Project
FX This work was carried out with the aid of a grant from the Canadian
Space Agency, Longueuil, Quebec, Canada. Arctic logistics support was
provided by the Polar Continental Shelf Project. Mars Society
International and Mars Society Canada are acknowledged for overall
project management and support of FMARS2007. Finally, Paul Graham
provided technical aid for on-site monitoring system deployment.
NR 22
TC 4
Z9 4
U1 5
U2 6
PU ELSEVIER SCI LTD
PI OXFORD
PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND
SN 0273-1177
J9 ADV SPACE RES
JI Adv. Space Res.
PD APR 15
PY 2009
VL 43
IS 8
BP 1256
EP 1274
DI 10.1016/j.asr.2009.01.009
PG 19
WC Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology &
Atmospheric Sciences
SC Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences
GA 438OV
UT WOS:000265565900013
ER
PT J
AU Murphy, KL
Rygalov, VY
Johnson, SB
AF Murphy, K. L.
Rygalov, V. Ye.
Johnson, S. B.
TI Minimal support technology and in situ resource utilization for risk
management of planetary spaceflight missions
SO ADVANCES IN SPACE RESEARCH
LA English
DT Article
DE In situ resource utilization; System closure; Reliability;
Interplanetary mission; System degradation; Risk mitigation
ID SPACE STATION; SYSTEM; MARS; MAINTENANCE; EXPLORATION
AB All artificial systems and components in space degrade at higher rates than oil Earth, depending in part oil environmental conditions, design approach, assembly technologies, and the materials used. This degradation involves not only the hardware and software systems but the humans that interact with those systems. All technological functions and systems can be expressed through functional dependence:
[Function] similar to [ERU] * [RUIS] * [ISR]/[DR]: where
[ERU] efficiency (rate) of environmental resource utilization
[RUIS] resource utilization infrastructure
[ISR] in situ resources
[DR] degradation rate
The limited resources of spaceflight and open space for autonomous missions require a high reliability (maximum possible, approaching 100%) for system functioning and operation, and must minimize the rate of any system degradation. To date, only a continuous human presence with a system in the spaceflight environment can absolutely mitigate those degradations. This mitigation is based on environmental amelioration for both the technology systems, as repair of data and spare parts, and the humans, as exercise and psychological support. Such maintenance now requires huge infrastructures, including research and development complexes and management agencies, which currently cannot move beyond the Earth. When considering what is required to move manned spaceflight from near Earth stations to remote locations such as Mars, what are the minimal technologies and infrastructures necessary for autonomous restoration of a degrading system in space? In all of the known system factors of a mission to Mars that reduce the mass load, increase the reliability, and reduce the mission's overall risk, the current common denominator is the use of undeveloped or untested technologies.
None of the technologies required to significantly reduce the risk for critical systems are currently available at acceptable readiness levels.
Long term interplanetary missions require that space programs produce a craft with all systems integrated so that they arc of the highest reliability. Right now, with current technologies, we cannot guarantee this reliability for a crew of six for 1000 days to Mars and back. Investigation of the technologies to answer this need and a focus of resources and research oil their advancement would significantly improve chances for a safe and successful mission. (C) 2008 COSPAR. Published by Elsevier Ltd. All rights reserved.
C1 [Murphy, K. L.] NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA.
[Rygalov, V. Ye.] Univ N Dakota, Dept Space Studies, Grand Forks, ND 58202 USA.
[Johnson, S. B.] Univ Colorado Colorado Springs, Larkspur, CO 80118 USA.
RP Murphy, KL (reprint author), NASA, George C Marshall Space Flight Ctr, Bldg 4600,Room 5318, Huntsville, AL 35812 USA.
EM karen.l.murphy@nasa.gov
NR 47
TC 2
Z9 2
U1 1
U2 3
PU ELSEVIER SCI LTD
PI OXFORD
PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND
SN 0273-1177
J9 ADV SPACE RES
JI Adv. Space Res.
PD APR 15
PY 2009
VL 43
IS 8
BP 1275
EP 1284
DI 10.1016/j.asr.2008.12.010
PG 10
WC Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology &
Atmospheric Sciences
SC Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences
GA 438OV
UT WOS:000265565900014
ER
PT J
AU Laity, JE
Bridges, NT
AF Laity, Julie E.
Bridges, Nathan T.
TI Ventifacts on Earth and Mars: Analytical, field, and laboratory studies
supporting sand abrasion and windward feature development
SO GEOMORPHOLOGY
LA English
DT Article
DE Aeolian geomorphology; Ventifacts; Aeolian abrasion; Wind erosion; Mars;
Deserts
ID PATHFINDER LANDING SITE; MERIDIANI-PLANUM; SEDIMENT-TRANSPORT;
OPPORTUNITY ROVER; COACHELLA VALLEY; GUSEV CRATER; DRIVEN SAND;
CALIFORNIA; EROSION; DUST
AB Terrestrial ventifacts - rocks that have been abraded by windblown particles - are found in desert, periglacial, and coastal environments. On Mars, their abundance suggests that aeolian abrasion is one of the most significant erosional processes on the planet. There are several conflicting viewpoints concerning the efficacy of potential abrasive agents, principally sand and dust, and the relationships between wind direction and ventifact form. Our research, supported by a review of the literature, shows that sand, rather than dust or other materials, is the principle abrasive agent on Earth and Mars. Relative to dust, sand delivers about 1000x the energy onto rock surfaces on a per particle basis. Even multiple dust collisions will do little or no damage because the stress field from the impact is much smaller than the spacing of microflaws in the rock. The abrasion profiles of terrestrial ventifacts are consistent with a kinetic energy flux due to saltating sand, not airborne dust. Furthermore, Scanning Electron Microscope images reveal surfaces that are fractured and cleaved by sand grain impact. With respect to their distribution, ventifacts are found in regions that contain sand or did so in the past, but are not found where only dust activity occurs. Contrary to some published reports, our evidence from field studies, analytical models, and wind tunnel and other experiments indicates that windward, not leeward, abrasion is responsible for facet development and feature formation (pits, flutes, and grooves). Leeward abrasion is confined to fluvial conditions, in which the high viscosity and density of water are able to entrain sand-size material in vortices. Therefore, ventifacts and abraded terrain provide an unambiguous proxy for the direction of the highest velocity winds, and can be used to reconstruct palaeowind flow. (C) 2008 Elsevier B.V. All rights reserved.
C1 [Laity, Julie E.] Calif State Univ Northridge, Dept Geog, Northridge, CA 91330 USA.
[Bridges, Nathan T.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
RP Laity, JE (reprint author), Calif State Univ Northridge, Dept Geog, 18111 Nordhaff St, Northridge, CA 91330 USA.
EM julie.laity@csun.edu; nathan.bridges@jpl.nasa.gov
RI Bridges, Nathan/D-6341-2016
FU NASA's Planetary Geology and Geophysics Program
FX We are grateful to A. Razdan and his research group at Arizona State
University, who conducted the laser scans and made the derived models.
We would also like to thank S.A.D'Agostino and M. Petkov at the jet
Propulsion Laboratory for performing the SEM analyses. We would like to
thank M. Banks, M. Benzit, and E.E. Eddlemon for assisting in the setup
and interpretation of the high speed video experiments and J-P. Wiens
for the filming and conversion of the HSV to MP4 files. David Deis of
the Department of Geography at California State University Northridge
drafted Fig. 13. Unofficial reviews from S.A. D'Agostino, M.P. Golombek,
and BJ. Thomson improved this paper. S.A. D'Agostino, R. Greeley, and
J.P, Marshall provided insight on rock elastic failure limits. N.T.
Bridges'work on this project was supported by NASA's Planetary Geology
and Geophysics Program. This paper benefited from reviews by two
anonymous referees.
NR 96
TC 31
Z9 34
U1 0
U2 12
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0169-555X
EI 1872-695X
J9 GEOMORPHOLOGY
JI Geomorphology
PD APR 15
PY 2009
VL 105
IS 3-4
BP 202
EP 217
DI 10.1016/j.geomorph.2008.09.014
PG 16
WC Geography, Physical; Geosciences, Multidisciplinary
SC Physical Geography; Geology
GA 426XQ
UT WOS:000264742100004
ER
PT J
AU Juarez, MD
Marcus, S
Dornbrack, A
Schroder, TM
Kivi, R
Iijima, BA
Hajj, GA
Mannucci, AJ
AF Juarez, M. de la Torre
Marcus, S.
Doernbrack, A.
Schroder, T. M.
Kivi, R.
Iijima, B. A.
Hajj, G. A.
Mannucci, A. J.
TI Detection of temperatures conducive to Arctic polar stratospheric clouds
using CHAMP and SAC-C radio occultation data
SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
LA English
DT Article
ID GLOBAL POSITIONING SYSTEM; GRAVITY-WAVE ACTIVITY; GPS OCCULTATION;
EARTHS ATMOSPHERE; DEPLETION; OZONE; WATER; DISTRIBUTIONS; METEOROLOGY;
PARTICLES
AB We use global positioning system radio occultation (GPSRO) data from the Challenging Mini-Satellite Payload for Geophysical Research and Application (CHAMP) and Satelite de Applicaciones Cientificas-C (SAC-C) low Earth orbiting satellites to investigate the occurrence of air with temperatures cold enough to allow the formation of polar stratospheric clouds (PSCs) during four successive Arctic winters spanning 2001 to 2005. The GPSRO data are validated and compared with analysis data from the European Centre for Medium-Range Weather Forecasts using a series of criteria designed to eliminate faulty soundings but retain profiles which do not differ too strongly from the model data. We find that GPSRO is able to detect more PSC-prone temperature profiles during winters with disturbed conditions (in particular during December 2001 and 2003) than the analysis, but that the model fully captures the extent of PSC-prone air in winters with strong, cold vortices (in particular December 2002 and January 2005). Examination of detailed profiles for December 2001 shows that this difference is due to the ability of GPSRO to detect short-vertical wavelength features which may represent either localized gravity or global-scale planetary waves. Since the GPSRO data are now being directly assimilated into operational analysis systems, the benefits of the higher vertical resolution retrievals it provides should become evident in future observational studies of PSC formation and ozone loss, particularly under the disturbed conditions noted in several recent winters.
C1 [Juarez, M. de la Torre; Marcus, S.; Schroder, T. M.; Iijima, B. A.; Hajj, G. A.; Mannucci, A. J.] CALTECH, Jet Prop Lab, Pasadena, CA 91189 USA.
[Doernbrack, A.] DLR, Inst Atmospher Phys, D-82230 Oberpfaffenhofen, Germany.
[Kivi, R.] FMI, Arctic Res Ctr, FI-99600 Sodankyla, Finland.
[Schroder, T. M.] Natl Acad Sci, Natl Res Council, Washington, DC 20418 USA.
RP Juarez, MD (reprint author), CALTECH, Jet Prop Lab, MS 169-237,4800 Oak Grove Dr, Pasadena, CA 91189 USA.
EM mtj@jpl.nasa.gov
OI Marcus, Steven/0000-0002-5763-6961
NR 47
TC 4
Z9 4
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 APR 15
PY 2009
VL 114
AR D07112
DI 10.1029/2008JD011261
PG 13
WC Meteorology & Atmospheric Sciences
SC Meteorology & Atmospheric Sciences
GA 435FH
UT WOS:000265328800003
ER
PT J
AU Kaul, AB
AF Kaul, Anupama B.
TI Gas sensing with long, diffusively contacted single-walled carbon
nanotubes
SO NANOTECHNOLOGY
LA English
DT Article
ID OHMIC CONTACTS; TRANSPORT; SENSORS; WIRES
AB A carbon nanotube thermal-conductivity-based pressure or gas sensor is described, which utilizes 5-10 mu m long, diffusively contacted single-walled nanotubes (SWNTs). Low temperature electrical transport measurements for these tubes were suggestive of a thermally activated hopping mechanism for electron localization, where a hopping energy of similar to 39 meV was computed. A negative differential conductance regime was also detected in suspended tubes, released using critical point drying, at high bias voltages. The pressure or gas sensitivity increased more dramatically as the bias power was increased up to 14 mu W, which was interpreted in the context of the high optical phonon density in the suspended SWNTs. Such devices are promising for use as pressure sensors, as well as for the chemical identification of species having differing gas thermal conductivities.
C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
RP Kaul, AB (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA.
EM anupama.b.kaul@jpl.nasa.gov
FU Defense Advanced Research Project Agency [715839, NAS7-03001]
FX We greatly acknowledge James Wishard for his assistance in the JPL
Micro-Devices Laboratory, Dr Eric Wong for CNT growth and annealing, Dr
Henry LeDuc for use of the low temperature electrical measurement
facility, Dr. Harish Manohara for initial interest, and Mr Ron Ruiz for
SEM imaging. This research was carried out at the Jet Propulsion
Laboratory, California Institute of Technology, under a contract with
the National Aeronautics and Space Administration and was funded by a
Defense Advanced Research Project Agency seedling fund (Task Order NMO#
715839 under NAS7-03001).
NR 20
TC 9
Z9 9
U1 0
U2 1
PU IOP PUBLISHING LTD
PI BRISTOL
PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND
SN 0957-4484
J9 NANOTECHNOLOGY
JI Nanotechnology
PD APR 15
PY 2009
VL 20
IS 15
AR 155501
DI 10.1088/0957-4484/20/15/155501
PG 6
WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary;
Physics, Applied
SC Science & Technology - Other Topics; Materials Science; Physics
GA 424BD
UT WOS:000264539600010
PM 19420548
ER
PT J
AU Calaway, MJ
Stansbery, EK
Keller, LP
AF Calaway, Michael J.
Stansbery, Eileen K.
Keller, Lindsay P.
TI Genesis capturing the sun: Solar wind irradiation at Lagrange 1
SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM
INTERACTIONS WITH MATERIALS AND ATOMS
LA English
DT Article
DE Irradiation damage; Radiation damage; NASA Genesis Mission; Solar wind;
Space weathering; Silicon defects
ID ION-IMPLANTED SILICON; AMORPHIZATION; RADIATION; MISSION; RATES; NEON
AB Genesis, a member of NASAs Discovery Mission program, is the world's first sample return mission since the Apollo program to bring home solar matter in ultra-pure materials. Outside the protection of Earth's magnetosphere at the Earth-Sun Lagrange 1 point, the deployed sample collectors were directly exposed to solar wind irradiation. The natural process of solar wind ion implantation into a highly pure silicon (Si) bulk composition array collector has been measured by spectroscopic ellipsometry and scanning transmission electron microscopy (STEM). Ellipsometry results show that bulk solar wind ions composed of approximately 95% H(+), 4% He(+) and < 1% other elements physically altered the first 59-63 nm of crystalline silicon substrate during 852.8 days of solar exposure. STEM analysis confirms that the solar accelerated ions caused significant strain and visible structural defects to the silicon structure forming a 60-75 nm thick irradiation damage region directly below the surface SiO(2) native oxide layer. Monte Carlo simulations of solar wind H, He, C, O, Ne, Mg, Si and Fe ion collisions in the Si collector with fluences calculated from the Genesis and ACE spacecrafts were used to estimate the energy deposited and Si vacancies produced by nuclear stopping in a flight-like Si bulk array collector. The coupled deposited energy model with the flown Genesis Si in situ measurements provides new insight into the basic principles of solar wind diffusion and space weathering of materials outside Earth's magnetosphere. (c) 2009 Elsevier B.V. All rights reserved.
C1 [Calaway, Michael J.] NASA, Lyndon B Johnson Space Ctr, Jacobs ESCG, Houston, TX 77058 USA.
RP Calaway, MJ (reprint author), NASA, Lyndon B Johnson Space Ctr, Jacobs ESCG, Mail Code KT,2101 NASA Pkwy, Houston, TX 77058 USA.
EM michael.calaway-1@nasa.gov
NR 51
TC 3
Z9 3
U1 1
U2 7
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0168-583X
J9 NUCL INSTRUM METH B
JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms
PD APR 15
PY 2009
VL 267
IS 7
BP 1101
EP 1108
DI 10.1016/j.nimb.2009.01.132
PG 8
WC Instruments & Instrumentation; Nuclear Science & Technology; Physics,
Atomic, Molecular & Chemical; Physics, Nuclear
SC Instruments & Instrumentation; Nuclear Science & Technology; Physics
GA 446XN
UT WOS:000266155000012
ER
PT J
AU Aghara, SK
Blattnig, SR
Norbury, JW
Singleterry, RC
AF Aghara, S. K.
Blattnig, S. R.
Norbury, J. W.
Singleterry, R. C.
TI Monte Carlo analysis of pion contribution to absorbed dose from Galactic
cosmic rays
SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM
INTERACTIONS WITH MATERIALS AND ATOMS
LA English
DT Article
DE Pions; Mesons; Space radiation; Monte Carlo; Neutron flux; Photon flux;
Absorbed dose; GCR; Space; Heavy ions
ID RADIATION ENVIRONMENT; CODE; SIMULATIONS; TRANSPORT; ENERGY; MCNPX
AB Accurate knowledge of the physics of interaction, particle production and transport is necessary to estimate the radiation damage to equipment used on spacecraft and the biological effects of space radiation. For long duration astronaut missions, both on the International Space Station and the planned manned missions to Moon and Mars, the shielding strategy must include a comprehensive knowledge of the secondary radiation environment. The distribution of absorbed dose and dose equivalent is a function of the type, energy and population of these secondary products. Galactic cosmic rays (GCR) comprised of protons and heavier nuclei have energies from a few MeV per nucleon to the ZeV region, with the spectra reaching flux maxima in the hundreds of MeV range. Therefore, the MeV-GeV region is most important for space radiation. Coincidentally, the pion production energy threshold is about 280 MeV. The question naturally arises as to how important these particles are with respect to space radiation problems. The space radiation transport code, HZETRN (High charge (Z) and Energy TRaNsport), currently used by NASA, performs neutron. proton and heavy ion transport explicitly, but it does not take into account the production and transport of mesons, photons and leptons. In this paper, we present results from the Monte Carlo code MCNPX (Monte Carlo N-Particle eXtended), showing the effect of leptons and mesons when they are produced and transported in a GCR environment. (c) 2009 Elsevier B.V. All rights reserved.
C1 [Aghara, S. K.] Prairie View A&M Univ, Chem Engn Nucl Program, Prairie View, TX 77446 USA.
[Blattnig, S. R.; Norbury, J. W.; Singleterry, R. C.] NASA, Langley Res Ctr, Hampton, VA 23681 USA.
RP Aghara, SK (reprint author), Prairie View A&M Univ, Chem Engn Nucl Program, POB 519,MS 2505, Prairie View, TX 77446 USA.
EM Sukesh.K.Aghara@nasa.gov
FU NASA Administrator's Fellow Program (NAFP); United Negro College Funds
Special Programs (UNCFSP) [003844]
FX We thank Dr. Ryan Norman, Dr. Francis Badavi and Dr. Steven Walker for
reviewing the manuscript. This research was supported by NASA
Administrator's Fellow Program (NAFP) managed by United Negro College
Funds Special Programs (UNCFSP), Grant No. 003844.
NR 33
TC 19
Z9 19
U1 1
U2 5
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0168-583X
J9 NUCL INSTRUM METH B
JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms
PD APR 15
PY 2009
VL 267
IS 7
BP 1115
EP 1124
DI 10.1016/j.nimb.2009.01.136
PG 10
WC Instruments & Instrumentation; Nuclear Science & Technology; Physics,
Atomic, Molecular & Chemical; Physics, Nuclear
SC Instruments & Instrumentation; Nuclear Science & Technology; Physics
GA 446XN
UT WOS:000266155000014
ER
PT J
AU Norbury, JW
AF Norbury, John W.
TI Total cross section parameterizations for pion production in
nucleon-nucleon collisions
SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM
INTERACTIONS WITH MATERIALS AND ATOMS
LA English
DT Article
DE Cross section; Pion production; Nuclear reactions
ID PP INTERACTIONS; CHARGED PIONS; GEV-C; GAMMA PRODUCTION; GEV/C;
PARTICLE; MULTIPLICITIES; PROTONS
AB Total cross section parameterizations for neutral and charged pion production in nucleon-nucleon collisions are compared to experimental data over the projectile momentum range from threshold to 300 GeV. Both proton-proton and proton-neutron reactions are considered. Overall excellent agreement between parameterizations and experiment is found, except for some disagreements near threshold. This gives much greater confidence to previously developed pion cross section formulas for nucleon-nucleon, proton-nucleus, and nucleus-nucleus reactions. These results are useful for particle transport. Published by Elsevier B.V.
C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA.
RP Norbury, JW (reprint author), NASA, Langley Res Ctr, Hampton, VA 23681 USA.
EM john.w.norbury@nasa.gov
NR 18
TC 2
Z9 2
U1 0
U2 0
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0168-583X
EI 1872-9584
J9 NUCL INSTRUM METH B
JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms
PD APR 15
PY 2009
VL 267
IS 7
BP 1209
EP 1212
DI 10.1016/j.nimb.2009.02.067
PG 4
WC Instruments & Instrumentation; Nuclear Science & Technology; Physics,
Atomic, Molecular & Chemical; Physics, Nuclear
SC Instruments & Instrumentation; Nuclear Science & Technology; Physics
GA 446XN
UT WOS:000266155000030
ER
PT J
AU Baldridge, AM
Hook, SJ
Grove, CI
Rivera, G
AF Baldridge, A. M.
Hook, S. J.
Grove, C. I.
Rivera, G.
TI The ASTER spectral library version 2.0
SO REMOTE SENSING OF ENVIRONMENT
LA English
DT Article
DE ASTER; Spectral library
ID SPACEBORNE THERMAL EMISSION; REFLECTION RADIOMETER ASTER; NEVADA;
IMAGES; MINERALS; CONTRAST; SPRINGS; SURFACE; FIELD
AB The Advanced Spaceborne Thermal Emission Reflection Radiometer (ASTER) on NASA's Terra platform has been widely used in geological and other science studies. In support of ASTER studies, a library of natural and man-made materials was compiled as the ASTER Spectral Library v1.2 and made available from http://speclib.jpl.nasa.gov. The library is a collection of contributions in a standard format with ancillary data from the jet Propulsion Laboratory (JPL), Johns Hopkins University (JHU) and the United States Geological Survey (USGS). A new version of the library (v2.0) is now available online or via CD, which includes major additions to the mineral and rock spectra. The ASTER library provides a comprehensive collection of over 2300 spectra of a wide variety of materials covering the wavelength range 0.4-15.4 Pm. (C) 2008 Elsevier Inc. All rights reserved.
C1 [Baldridge, A. M.; Hook, S. J.; Grove, C. I.; Rivera, G.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
RP Baldridge, AM (reprint author), CALTECH, Jet Prop Lab, MS 183-501,4800 Oak Grove Dr, Pasadena, CA 91109 USA.
EM alice.m.baldridge@jpl.nasa.gov
FU California Institute of Technology, Government sponsorship
FX The research described in this paper was carried out at the jet
Propulsion Laboratory, California Institute of Technology, under a
contract with the National Aeronautics and Space Administration. (C)
2008 California Institute of Technology, Government sponsorship is
acknowledged.
NR 18
TC 415
Z9 431
U1 4
U2 43
PU ELSEVIER SCIENCE INC
PI NEW YORK
PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA
SN 0034-4257
J9 REMOTE SENS ENVIRON
JI Remote Sens. Environ.
PD APR 15
PY 2009
VL 113
IS 4
BP 711
EP 715
DI 10.1016/j.rse.2008.11.007
PG 5
WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic
Technology
SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science &
Photographic Technology
GA 423NQ
UT WOS:000264503400002
ER
PT J
AU Zhang, QY
Middleton, EM
Margolis, HA
Drolet, GG
Barr, AA
Black, TA
AF Zhang, Qingyuan
Middleton, Elizabeth M.
Margolis, Hank A.
Drolet, Guillaume G.
Barr, Alan A.
Black, T. Andrew
TI Can a satellite-derived estimate of the fraction of PAR absorbed by
chlorophyll (FAPAR(chl)) improve predictions of light-use efficiency and
ecosystem photosynthesis for a boreal aspen forest?
SO REMOTE SENSING OF ENVIRONMENT
LA English
DT Article
DE MODIS; Aspen; Chlorophyll; Ecosystem flux; Gross primary production;
Gross ecosystem production; Light use efficiency (LUE); LUEchl;
FAPAR(chl); NDVI; LUEtower
ID GROSS PRIMARY PRODUCTION; SURFACE PARAMETERIZATION SIB2; DECIDUOUS
BROADLEAF FOREST; GLOBAL PRIMARY PRODUCTION; NET PRIMARY PRODUCTION;
LEAF-AREA INDEX; PRODUCT VALIDATION; ATMOSPHERIC GCMS; MODIS DATA; MODEL
AB We used daily MODerate resolution Imaging Spectroradiometer (MODIS) imagery obtained over a five-year period to analyze the seasonal and inter-annual variability of the fraction of absorbed photosynthetically active radiation (FAPAR) and photosynthetic light use efficiency (LUE) for the Southern Old Aspen (SOA) flux tower site located near the southern limit of the boreal forest in Saskatchewan, Canada. To obtain the spectral characteristics of a standardized land area to compare with tower measurements, we scaled up the nominal 500 m MODIS products to a 2.5 km x 2.5 kin area (5 x 5 MODIS 500 m grid cells). We then used the scaled-up MODIS products in a coupled canopy-leaf radiative transfer model, PROSAIL-2, to estimate the fraction of absorbed photosynthetically active radiation (APAR) by the part of the canopy dominated by chlorophyll (FAPAR(chl)) versus that by the whole canopy (FAPAR(canopy)). Using the additional information provided by flux tower-based measurements of gross ecosystem production (GEP) and incident PAR, we determined 90-minute averages for APAR and LUE (slope of GEP:APAR) for both the physiologically active foliage (APAR(chl), LUEchl) and for the entire canopy (APAR(canopy), LUEcanopy).
The flux tower measurements of GEP were strongly related to the MODIS-derived estimates of APAR(chl), (r(2)=0.78) but only weakly related to APAR(canopy) (r(2)=0.33). Gross LUE between 2001 and 2005 for LUEchl was 0.0241 mu mol C mu mol(-1) PPFD whereas LUEcanopy 6% lower. Time series of the 5-year normalized difference vegetation index (NDVI) were used to estimate the average length of the core growing season as days of year 152-259. Inter-annual variability in the core growing season LUEchl (mu mol C mu mol(-1) PPFD) ranged from 0.0225 in 2003 to 0.0310 in 2004. The five-year time series of LUEchl corresponded well with both the seasonal phase and amplitude of LUE from the tower measurements but this was not the case for LUEcanopy. We conclude that LUE,h, derived from MODIS observations could provide a more physiologically realistic parameter than the more commonly used LUEcanopy as an input to large-scale photosynthesis models. (C) 2009 Elsevier Inc. All rights reserved.
C1 [Zhang, Qingyuan; Middleton, Elizabeth M.] NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Greenbelt, MD 20771 USA.
[Zhang, Qingyuan] Univ Maryland, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA.
[Margolis, Hank A.; Drolet, Guillaume G.] Univ Laval, Fac Foresterie & Geomat, CEF, Quebec City, PQ G1K 7P4, Canada.
[Barr, Alan A.] Meteorol Serv Canada, Atmospher Sci & Technol Directorate, Saskatoon, SK S7N 3H5, Canada.
[Black, T. Andrew] Univ British Columbia, Biometeorol & Soil Phys Grp, Vancouver, BC V6T 1Z4, Canada.
RP Zhang, QY (reprint author), NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Bldg 33,Room G321,Code 614-4, Greenbelt, MD 20771 USA.
EM qyz72@yahoo.com
FU NASA Carbon Cycle Science Program; North American Carbon Program; FCRN
and BERMS programs through several Canadian funding sources (Environment
Canada, the Canadian Forest Service, NSERC, CFCAS, BIOCAP, Action Plan
2000 and PERD)
FX This project was supported by the NASA Carbon Cycle Science Program (Dr.
Diane Wickland, Program Manager) under the auspices of the North
American Carbon Program. Support was provided to the FCRN and BERMS
programs through several Canadian funding sources (Environment Canada,
the Canadian Forest Service, NSERC, CFCAS, BIOCAP, Action Plan 2000 and
PERD).
NR 45
TC 59
Z9 59
U1 3
U2 25
PU ELSEVIER SCIENCE INC
PI NEW YORK
PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA
SN 0034-4257
EI 1879-0704
J9 REMOTE SENS ENVIRON
JI Remote Sens. Environ.
PD APR 15
PY 2009
VL 113
IS 4
BP 880
EP 888
DI 10.1016/j.rse.2009.01.002
PG 9
WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic
Technology
SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science &
Photographic Technology
GA 423NQ
UT WOS:000264503400016
ER
PT J
AU Balin, Y
Kaul, B
Kokhanenko, G
Winker, D
AF Balin, Yurii
Kaul, Bruno
Kokhanenko, Grigorii
Winker, David
TI Application of circularly polarized laser radiation for sensing of
crystal clouds
SO OPTICS EXPRESS
LA English
DT Article
ID LIDAR; ORIENTATION; DEPOLARIZATION; PARTICLES
AB The application of circularly polarized laser radiation and measurement of the fourth Stokes parameter of scattered radiation considerably reduce the probability of obtaining ambiguous results for radiation depolarization in laser sensing of crystal clouds. The uncertainty arises when cloud particles appear partially oriented by their large diameters along a certain azimuth direction. Approximately in 30% of all cases, the measured depolarization depends noticeably on the orientation of the lidar reference plane with respect to the particle orientation direction. In this case, the corridor of the most probable depolarization values is about 0.1-0.15, but in individual cases, it can be noticeably wider. The present article considers theoretical aspects of this phenomenon and configuration of a lidar capable of measuring the fourth Stokes parameter together with an algorithm of lidar signal processing in the presence of optically thin cloudiness when molecular scattering cannot be neglected. It is demonstrated that the element a(44) of the normalized backscattering phase matrix (BSPM) can be measured. Results of measurements are independent of the presence or absence of azimuthal particle orientation. For sensing in the zenith or nadir, this element characterizes the degree of horizontal orientation of long particle diameters under the action of aerodynamic forces arising during free fall of particles. (C) 2009 Optical Society of America
C1 [Balin, Yurii; Kaul, Bruno; Kokhanenko, Grigorii] Russian Acad Sci, Siberian Branch, Inst Atmospher Opt, Tomsk 634055, Russia.
[Winker, David] NASA, Langley Res Ctr, Hampton, VA 23681 USA.
RP Balin, Y (reprint author), Russian Acad Sci, Siberian Branch, Inst Atmospher Opt, Tomsk 634055, Russia.
EM balin@iao.ru
NR 19
TC 10
Z9 12
U1 0
U2 3
PU OPTICAL SOC AMER
PI WASHINGTON
PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA
SN 1094-4087
J9 OPT EXPRESS
JI Opt. Express
PD APR 13
PY 2009
VL 17
IS 8
BP 6849
EP 6859
DI 10.1364/OE.17.006849
PG 11
WC Optics
SC Optics
GA 432BQ
UT WOS:000265108900103
PM 19365512
ER
PT J
AU Mitra, S
Sengupta, AS
Ray, S
Saha, R
Souradeep, T
AF Mitra, Sanjit
Sengupta, Anand S.
Ray, Subharthi
Saha, Rajib
Souradeep, Tarun
TI Cosmic microwave background power spectrum estimation with non-circular
beam and incomplete sky coverage
SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
LA English
DT Article
DE cosmic microwave background
ID PROBE WMAP OBSERVATIONS; PRIMORDIAL INHOMOGENEITY; STATISTICAL ISOTROPY;
HARMONIC-ANALYSIS; 2003 FLIGHT; PYTHON-V; ANISOTROPY; POLARIZATION;
MAPS; TEMPERATURE
AB Over the last decade, measurements of the cosmic microwave background (CMB) anisotropy have spearheaded the remarkable transition of cosmology into a precision science. However, addressing the systematic effects in the increasingly sensitive, high-resolution, 'full' sky measurements from different CMB experiments poses a stiff challenge. The analysis techniques must not only be computationally fast to contend with the huge size of the data, but the higher sensitivity also limits the simplifying assumptions which can then be invoked to achieve the desired speed without compromising the final precision goals. While maximum likelihood is desirable, the enormous computational cost makes the suboptimal method of power spectrum estimation using pseudo-C-l unavoidable for high-resolution data. The debiasing of the pseudo-C-l needs account for non-circular beams, together with non-uniform sky coverage. We provide a (semi) analytic framework to estimate bias in the power spectrum due to the effect of beam non-circularity and non-uniform sky coverage, including incomplete/masked sky maps and scan strategy. The approach is perturbative in the distortion of the beam from non-circularity, allowing for rapid computations when the beam is mildly non-circular. We advocate that it is computationally advantageous to employ 'soft' azimuthally apodized masks whose spherical harmonic transform die down fast with m. We numerically implement our method for non-rotating beams. We present preliminary estimates of the computational cost to evaluate the bias for the upcoming CMB anisotropy probes (l(max) similar to 3000), with angular resolution comparable to the Planck surveyor mission. We further show that this implementation and estimate are applicable for rotating beams on equal declination scans, and can possibly be extended to simple approximations to other scan strategies.
C1 [Mitra, Sanjit; Ray, Subharthi; Saha, Rajib; Souradeep, Tarun] Interuniv Ctr Astron & Astrophys, Pune 411007, Maharashtra, India.
[Mitra, Sanjit; Saha, Rajib] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
[Sengupta, Anand S.] CALTECH, LIGO Lab, Pasadena, CA 91125 USA.
[Ray, Subharthi] Univ KwaZulu Natal, Sch Math Sci, Astrophys & Cosmol Res Unit, ZA-4000 Durban, South Africa.
[Saha, Rajib] Indian Inst Technol, Kanpur 208016, Uttar Pradesh, India.
RP Mitra, S (reprint author), Interuniv Ctr Astron & Astrophys, Post Bag 4, Pune 411007, Maharashtra, India.
EM Sanjit.Mitra@jpl.nasa.gov
FU Council of Scientific and Industrial Research (India)
FX SM would like to thank Council of Scientific and Industrial Research
(India) for supporting his research. Part of the writing of this paper
was carried out at the Jet Propulsion Laboratory, California Institute
of Technology, under a contract with the National Aeronautics and Space
Administration. We thank Kris Gorski, Jeff Jewel and Ben Wandelt for
providing the reference and a code for computing Wigner-d functions. We
thank Olivier Dore and Mike Nolta for providing us with the data files
of the non-circular beam correction estimated by the WMAP team. We
acknowledge the fruitful discussions with Francois Bouchet, Simon Prunet
and Charles Lawrence. Computations were carried out at the HPC facility
available at IUCAA.
NR 57
TC 8
Z9 8
U1 0
U2 0
PU OXFORD UNIV PRESS
PI OXFORD
PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND
SN 0035-8711
EI 1365-2966
J9 MON NOT R ASTRON SOC
JI Mon. Not. Roy. Astron. Soc.
PD APR 11
PY 2009
VL 394
IS 3
BP 1419
EP 1439
DI 10.1111/j.1365-2966.2008.14277.x
PG 21
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 428AP
UT WOS:000264820500018
ER
PT J
AU Temi, P
Brighenti, F
Mathews, WG
AF Temi, Pasquale
Brighenti, Fabrizio
Mathews, William G.
TI EVIDENCE OF STAR FORMATION IN LOCAL S0 GALAXIES: Spitzer OBSERVATIONS OF
THE SAURON SAMPLE
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE galaxies: elliptical and lenticular, cD; galaxies: ISM; infrared:
galaxies; infrared: ISM
ID ELLIPTIC GALAXIES; LENTICULAR GALAXIES; PROJECT; EMISSION; KINEMATICS;
COLORS; DUST
AB We discuss infrared Spitzer observations of early-type galaxies in the SAURON sample at 24, 60, and 170 mu m. When compared with 2MASS K s band luminosities, lenticular (S0) galaxies exhibit a much wider range of mid-to-far-infrared luminosities than elliptical (E) galaxies. Mid- and far-infrared emission from E galaxies is a combination of circumstellar or interstellar emission from local mass-losing red giant stars, dust buoyantly transported from the galactic cores into distant hot interstellar gas and dust accreted from the environment. The source of mid- and far-IR emission in S0 galaxies is quite different and is consistent with low levels of star formation, 0.02-0.2 M(circle dot) yr(-1), in cold, dusty gaseous disks. The infrared 24 mu m-70 mu m color is systematically lower for (mostly S0) galaxies with known molecular disks. Our observations support the conjecture that cold dusty gas in some S0 galaxies is created by stellar mass loss at approximately the same rate that it is consumed by star formation, so the mass depletion of these disks by star formation will be slow. Unlike E galaxies, the infrared luminosities of S0 galaxies correlate with both the mass of molecular gas and the stellar H beta spectral index, and all are related to the recent star formation rate (SFR). However, star formation rates estimated from the H beta-emission-line luminosities L(H beta) in SAURON S0 galaxies are generally much smaller. Since L(H beta) does not correlate with 24 mu m emission from dust heated by young stars, optical emission lines appear to be a poor indicator of SFRs in SAURON S0 galaxies. The absence of H beta emission may be due to a relative absence of OB stars in the initial mass function or to dust absorption of H beta emission lines.
C1 [Temi, Pasquale] NASA, Ames Res Ctr, Astrophys Branch, Moffett Field, CA 94035 USA.
[Temi, Pasquale] Univ Western Ontario, Dept Phys & Astron, London, ON N6A 3K7, Canada.
[Brighenti, Fabrizio; Mathews, William G.] Univ Calif Santa Cruz, Board Studies Astron & Astrophys, Univ Calif Observ, Lick Observ, Santa Cruz, CA 95064 USA.
[Brighenti, Fabrizio] Univ Bologna, Dipartimento Astron, I-40127 Bologna, Italy.
RP Temi, P (reprint author), NASA, Ames Res Ctr, Astrophys Branch, MS 245-6, Moffett Field, CA 94035 USA.
EM pasquale.temi@nasa.gov; fabrizio.brighenti@unibo.it; mathews@ucolick.org
FU NASA [1407, RSA 1276023]; Spitzer Theory Grant; NSF
FX This work is based on observations made with the Spitzer Space
Telescope, which is operated by the Jet Propulsion Laboratory,
California Institute of Technology, under NASA contract 1407. Support
for this work was provided by NASA through Spitzer Guest Observer grant
RSA 1276023. Studies of the evolution of hot gas in elliptical galaxies
at UC Santa Cruz are supported by a Spitzer Theory Grant and an NSF
grant for which we are very grateful. Finally we thank the referee for
thoughtful remarks.
NR 23
TC 43
Z9 43
U1 0
U2 3
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 APR 10
PY 2009
VL 695
IS 1
BP 1
EP 11
DI 10.1088/0004-637X/695/1/1
PG 11
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 427KZ
UT WOS:000264779500001
ER
PT J
AU Corbet, RHD
Zand, JJMI
Levine, AM
Marshall, FE
AF Corbet, R. H. D.
Zand, J. J. M. In't
Levine, A. M.
Marshall, F. E.
TI ROSSI X-RAY TIMING EXPLORER AND BeppoSAX OBSERVATIONS OF THE TRANSIENT
X-RAY PULSAR XTE J1859+083
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE stars: individual (XTE J1859+083); stars: neutron; X-rays: binaries
ID PROPORTIONAL COUNTER ARRAY; BINARY-SYSTEMS; CALIBRATION; ACCRETION;
CATALOG
AB We present observations of the 9.8 s X-ray pulsar XTE J1859+083 made with the All Sky Monitor (ASM) and Proportional Counter Array (PCA) on board the Rossi X-ray Timing Explorer, and the Wide Field Camera (WFC) on board BeppoSAX. The ASM data cover a 12 year time interval and show that an extended outburst occurred between approximately MJD 50,250 and 50,460 (1996 June 16 to 1997 January 12). The ASM data excluding this outburst interval suggest a possible modulation with a period of 60.65 +/- 0.08 days. Eighteen sets of PCA observations were obtained over an approximately one month interval in 1999. The flux variability measured with the PCA appears consistent with the possible period found with the ASM. The PCA measurements of the pulse period showed it to decrease nonmonotonically and then to increase significantly. Doppler shifts due to orbital motion rather than accretion torques appear to be better able to explain the pulse period changes. Observations with the WFC during the extended outburst give a position that is consistent with a previously determined PCA error box, but which has a significantly smaller error. The transient nature of XTE J1859+083 and the length of its pulse period are consistent with it being a Be/neutron star binary. The possible 60.65 day orbital period would be of the expected length for a Be star system with a 9.8 s pulse period.
C1 [Corbet, R. H. D.] Univ Maryland, Baltimore, MD USA.
[Corbet, R. H. D.] NASA, Goddard Space Flight Ctr, CRESST, Greenbelt, MD 20771 USA.
[Zand, J. J. M. In't] SRON, Netherlands Inst Space Res, NL-3584 CA Utrecht, Netherlands.
[Zand, J. J. M. In't] Univ Utrecht, Astron Inst, NL-3508 GA Utrecht, Netherlands.
[Levine, A. M.] MIT, Kavli Inst Astrophys & Space Res, Cambridge, MA 02139 USA.
RP Corbet, RHD (reprint author), Univ Maryland, Baltimore, MD USA.
EM corbet@umbc.edu; jeanz@sron.nl
NR 17
TC 2
Z9 2
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 APR 10
PY 2009
VL 695
IS 1
BP 30
EP 35
DI 10.1088/0004-637X/695/1/30
PG 6
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 427KZ
UT WOS:000264779500003
ER
PT J
AU Whittet, DCB
Cook, AM
Chiar, JE
Pendleton, YJ
Shenoy, SS
Gerakines, PA
AF Whittet, D. C. B.
Cook, A. M.
Chiar, J. E.
Pendleton, Y. J.
Shenoy, S. S.
Gerakines, P. A.
TI THE NATURE OF CARBON DIOXIDE BEARING ICES IN QUIESCENT MOLECULAR CLOUDS
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE dust, extinction; infrared: ISM; ISM: lines and bands; ISM: molecules
ID TAURUS DARK CLOUD; SPITZER-SPACE-TELESCOPE; YOUNG STELLAR OBJECTS;
INFRARED SPECTROGRAPH; SPECTROSCOPIC SURVEY; GRAIN MANTLES; CO2 ICE;
BACKGROUND STARS; INTERSTELLAR ICE; SWS OBSERVATIONS
AB The properties of the ices that form in dense molecular clouds represent an important set of initial conditions in the evolution of interstellar and preplanetary matter in regions of active star formation. Of the various spectral features available for study, the bending mode of solid CO(2) near 15 mu m has proven to be a particularly sensitive probe of physical conditions, especially temperature. We present new observations of this absorption feature in the spectrum of Q21-1, a background field star located behind a dark filament in the Cocoon Nebula (IC 5146). We show the profile of the feature to be consistent with a two-component (polar + nonpolar) model for the ices, based on spectra of laboratory analogs with temperatures in the range 10-20 K. The polar component accounts for similar to 85% of the CO(2) in the line of sight. We compare for the first time 15 mu m profiles in three widely separated dark clouds (Taurus, Serpens, and IC 5146), and show that they are indistinguishable to within observational scatter. Systematic differences in the observed CO(2)/H(2)O ratio in the three clouds have little or no effect on the 15 mu m profile. The abundance of elemental oxygen in the ices appears to be a unifying factor, displaying consistent behavior in the three clouds. We conclude that the ice formation process is robust and uniformly efficient, notwithstanding compositional variations arising from differences in how the O is distributed between the primary species (H(2)O, CO(2), and CO) in the ices.
C1 [Whittet, D. C. B.; Cook, A. M.] Rensselaer Polytech Inst, Dept Phys Appl Phys & Astron, Troy, NY 12180 USA.
[Chiar, J. E.] SETI Inst, Mountain View, CA 94043 USA.
[Pendleton, Y. J.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA.
[Shenoy, S. S.] CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA.
[Gerakines, P. A.] Univ Alabama, Dept Phys, Birmingham, AL 35294 USA.
RP Whittet, DCB (reprint author), Rensselaer Polytech Inst, Dept Phys Appl Phys & Astron, 110 8th St, Troy, NY 12180 USA.
RI Gerakines, Perry/B-9705-2009; Gerakines, Perry/D-2226-2012;
OI Gerakines, Perry/0000-0002-9667-5904; Whittet,
Douglas/0000-0001-8539-3891
FU NASA [NNX07AK38G, 1290823, 1266411, 1267778]
FX This work is based on observations made with the Spitzer Space
Telescope, which is operated by the Jet Propulsion Laboratory,
California Institute of Technology, under a contract with NASA. The
authors acknowledge NASA support from grant NNX07AK38G and JPL/Caltech
Support Agreement No. 1290823 (D. C. B. W.) and JPL/Caltech subcontracts
1266411 and 1267778 (J.E.C.). We are grateful to an anonymous referee
for helpful comments that led to improvements to this paper.
NR 46
TC 29
Z9 29
U1 0
U2 4
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 APR 10
PY 2009
VL 695
IS 1
BP 94
EP 100
DI 10.1088/0004-637X/695/1/94
PG 7
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 427KZ
UT WOS:000264779500008
ER
PT J
AU Horan, D
Acciari, VA
Bradbury, SM
Buckley, JH
Bugaev, V
Byrum, KL
Cannon, A
Celik, O
Cesarini, A
Chow, YCK
Ciupik, L
Cogan, P
Falcone, AD
Fegan, SJ
Finley, JP
Fortin, P
Fortson, LF
Gall, D
Gillanders, GH
Grube, J
Gyuk, G
Hanna, D
Hays, E
Kertzman, M
Kildea, J
Konopelko, A
Krawczynski, H
Krennrich, F
Lang, MJ
Lee, K
Moriarty, P
Nagai, T
Niemiec, J
Ong, RA
Perkins, JS
Pohl, M
Quinn, J
Reynolds, PT
Rose, HJ
Sembroski, GH
Smith, AW
Steele, D
Swordy, SP
Toner, JA
Vassiliev, VV
Wakely, SP
Weekes, TC
White, RJ
Williams, DA
Wood, MD
Zitzer, B
Aller, HD
Aller, MF
Baker, M
Barnaby, D
Carini, MT
Charlot, P
Dumm, JP
Fields, NE
Hovatta, T
Jordan, B
Kovalev, YA
Kovalev, YY
Krimm, HA
Kurtanidze, OM
Lahteenmaki, A
Le Campion, JF
Maune, J
Montaruli, T
Sadun, AC
Smith, S
Tornikoski, M
Turunen, M
Walters, R
AF Horan, D.
Acciari, V. A.
Bradbury, S. M.
Buckley, J. H.
Bugaev, V.
Byrum, K. L.
Cannon, A.
Celik, O.
Cesarini, A.
Chow, Y. C. K.
Ciupik, L.
Cogan, P.
Falcone, A. D.
Fegan, S. J.
Finley, J. P.
Fortin, P.
Fortson, L. F.
Gall, D.
Gillanders, G. H.
Grube, J.
Gyuk, G.
Hanna, D.
Hays, E.
Kertzman, M.
Kildea, J.
Konopelko, A.
Krawczynski, H.
Krennrich, F.
Lang, M. J.
Lee, K.
Moriarty, P.
Nagai, T.
Niemiec, J.
Ong, R. A.
Perkins, J. S.
Pohl, M.
Quinn, J.
Reynolds, P. T.
Rose, H. J.
Sembroski, G. H.
Smith, A. W.
Steele, D.
Swordy, S. P.
Toner, J. A.
Vassiliev, V. V.
Wakely, S. P.
Weekes, T. C.
White, R. J.
Williams, D. A.
Wood, M. D.
Zitzer, B.
Aller, H. D.
Aller, M. F.
Baker, M.
Barnaby, D.
Carini, M. T.
Charlot, P.
Dumm, J. P.
Fields, N. E.
Hovatta, T.
Jordan, B.
Kovalev, Y. A.
Kovalev, Y. Y.
Krimm, H. A.
Kurtanidze, O. M.
Lahteenmaki, A.
Le Campion, J. F.
Maune, J.
Montaruli, T.
Sadun, A. C.
Smith, S.
Tornikoski, M.
Turunen, M.
Walters, R.
TI MULTIWAVELENGTH OBSERVATIONS OF MARKARIAN 421 IN 2005-2006
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE BL Lacertae objects: individual (Markarian 421); gamma rays:
observations; X-rays: individual (Markarian 421)
ID ACTIVE GALACTIC NUCLEI; BL-LACERTAE OBJECTS; GAMMA-RAY EMISSION;
SPECTRAL SLOPE VARIABILITY; TEV BLAZAR MARKARIAN-421; X-RAY; LAC
OBJECTS; CORRELATED VARIABILITY; TIMING EXPLORER; PROTON BLAZAR
AB Since 2005 September, the Whipple 10 m Gamma-ray Telescope has been operated primarily as a blazar monitor. The five northern hemisphere blazars that have already been detected at the Whipple Observatory, Markarian 421 (Mrk 421), H1426+428, Mrk 501, 1ES 1959+650, and 1ES 2344+514, are monitored routinely each night that they are visible. We report on the Mrk 421 observations taken from 2005 November to 2006 June in the gamma-ray, X-ray, optical, and radio bands. During this time, Mrk 421 was found to be variable at all wavelengths probed. Both the variability and the correlations among different energy regimes are studied in detail here. A tentative correlation, with large spread, was measured between the X-ray and gamma-ray bands, while no clear correlation was evident among the other energy bands. In addition to this, the well-sampled spectral energy distribution of Mrk 421 (1101+384) is presented for three different activity levels. The observations of the other blazar targets will be reported separately.
C1 [Horan, D.; Byrum, K. L.; Hays, E.; Smith, A. W.] Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA.
[Acciari, V. A.; Moriarty, P.] Galway Mayo Inst Technol, Dept Phys & Life Sci, Galway, Ireland.
[Acciari, V. A.; Kildea, J.; Perkins, J. S.; Weekes, T. C.] Harvard Smithsonian Ctr Astrophys, Fred Lawrence Whipple Observ, Amado, AZ 85645 USA.
[Bradbury, S. M.; Rose, H. J.; White, R. J.] Univ Leeds, Sch Phys & Astron, Leeds LS2 9JT, W Yorkshire, England.
[Cannon, A.; Grube, J.; Quinn, J.] Washington Univ, Dept Phys, St Louis, MO 63130 USA.
[Cannon, A.; Grube, J.; Quinn, J.] Univ Coll Dublin, Sch Phys, Dublin 4, Ireland.
[Celik, O.; Chow, Y. C. K.; Fegan, S. J.; Ong, R. A.; Vassiliev, V. V.; Wood, M. D.] Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA.
[Cesarini, A.; Gillanders, G. H.; Lang, M. J.; Toner, J. A.] Natl Univ Ireland, Sch Phys, Galway, Ireland.
[Ciupik, L.; Fortson, L. F.; Gyuk, G.; Steele, D.] Adler Planetarium & Astron Museum, Dept Astron, Chicago, IL 60605 USA.
[Cogan, P.; Hanna, D.] McGill Univ, Dept Phys, Montreal, PQ H3A 2T8, Canada.
[Falcone, A. D.] Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA.
[Finley, J. P.; Gall, D.; Sembroski, G. H.; Zitzer, B.] Purdue Univ, Dept Phys, W Lafayette, IN 47907 USA.
[Fortin, P.] Columbia Univ, Barnard Coll, Dept Phys & Astron, New York, NY 10027 USA.
[Hays, E.; Swordy, S. P.; Wakely, S. P.] Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA.
[Hays, E.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
[Kertzman, M.] Depauw Univ, Dept Phys & Astron, Greencastle, IN 46135 USA.
[Konopelko, A.] Pittsburg State Univ, Dept Phys, Pittsburg, KS 66762 USA.
[Krennrich, F.; Nagai, T.; Niemiec, J.; Pohl, M.] Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA.
[Niemiec, J.] Inst Fizyki Hadrowej PAN, PL-31342 Krakow, Poland.
[Reynolds, P. T.] Cork Inst Technol, Dept Appl Phys & Instrumentat, Cork, Ireland.
[Williams, D. A.] Univ Calif Santa Cruz, Santa Cruz Inst Particle Phys, Santa Cruz, CA 95064 USA.
[Williams, D. A.] Univ Calif Santa Cruz, Dept Phys, Santa Cruz, CA 95064 USA.
[Aller, H. D.; Aller, M. F.] Univ Michigan, Dept Astron, Ann Arbor, MI 48109 USA.
[Baker, M.; Dumm, J. P.; Fields, N. E.; Montaruli, T.] Univ Wisconsin, Madison, WI 53706 USA.
[Barnaby, D.; Carini, M. T.; Maune, J.; Smith, S.; Walters, R.] Western Kentucky Univ, Bowling Green, KY 42104 USA.
[Charlot, P.; Le Campion, J. F.] Univ Bordeaux, Observ Aquitain Sci Univ, F-33271 Floirac, France.
[Charlot, P.; Le Campion, J. F.] CNRS, UMR 5804, Lab Astrophys Bordeaux, F-33271 Floirac, France.
[Hovatta, T.; Lahteenmaki, A.; Tornikoski, M.; Turunen, M.] Helsinki Univ Technol, Metsahovi Radio Observ, Kylmala 02540, Finland.
[Jordan, B.] Dublin Inst Adv Studies, Sch Cosm Phys, Dublin 4, Ireland.
[Kovalev, Y. A.; Kovalev, Y. Y.] Ctr Astro Space, PN Lebedev Phys Inst, Moscow 117997, Russia.
[Kovalev, Y. Y.] Max Planck Inst Radioastron, D-53121 Bonn, Germany.
[Krimm, H. A.] CRESST, Greenbelt, MD 20771 USA.
[Krimm, H. A.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
[Krimm, H. A.] Univ Space Res Assoc, Columbia, MD 21044 USA.
[Kurtanidze, O. M.] Abastumani Observ, Abastumani, GA USA.
[Sadun, A. C.] Univ Colorado, Dept Phys, Denver, CO 80208 USA.
RP Horan, D (reprint author), Argonne Natl Lab, Div High Energy Phys, 9700 S Cass Ave, Argonne, IL 60439 USA.
EM deirdre.horan@gmail.com
RI Kovalev, Yuri/J-5671-2013; Lahteenmaki, Anne/L-5987-2013; Hays,
Elizabeth/D-3257-2012; Kurtanidze, Omar/J-6237-2014; Kovalev,
Yuri/N-1053-2015
OI Kovalev, Yuri/0000-0001-9303-3263;
NR 61
TC 35
Z9 35
U1 0
U2 4
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 APR 10
PY 2009
VL 695
IS 1
BP 596
EP 618
DI 10.1088/0004-637X/695/1/596
PG 23
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 427KZ
UT WOS:000264779500050
ER
PT J
AU Vinko, J
Sarneczky, K
Balog, Z
Immler, S
Sugerman, BEK
Brown, PJ
Misselt, K
Szabo, GM
Csizmadia, S
Kun, M
Klagyivik, P
Foley, RJ
Filippenko, AV
Csak, B
Kiss, LL
AF Vinko, J.
Sarneczky, K.
Balog, Z.
Immler, S.
Sugerman, B. E. K.
Brown, P. J.
Misselt, K.
Szabo, Gy. M.
Csizmadia, Sz.
Kun, M.
Klagyivik, P.
Foley, R. J.
Filippenko, A. V.
Csak, B.
Kiss, L. L.
TI THE YOUNG, MASSIVE, STAR CLUSTER SANDAGE-96 AFTER THE EXPLOSION OF
SUPERNOVA 2004dj IN NGC 2403
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE supernovae: individual (2004dj)
ID RED SUPERGIANT PROGENITOR; EVOLUTIONARY SYNTHESIS MODELS;
SPACE-TELESCOPE IMAGES; II-P SUPERNOVAE; STELLAR POPULATIONS; MAGELLANIC
CLOUDS; NEARBY GALAXIES; AGB STARS; X-RAY; SWIFT
AB The bright Type II-plateau supernova (SN) 2004dj occurred within the young, massive stellar cluster Sandage-96 in a spiral arm of NGC 2403. New multiwavelength observations obtained with several ground-based and space-based telescopes were combined to study the radiation from Sandage-96 after SN 2004dj faded away. Sandage-96 started to dominate the flux in the optical bands starting from 2006 September (similar to 800 days after explosion). The optical fluxes are equal to the pre-explosion ones within the observational uncertainties. An optical Keck spectrum obtained similar to 900 days after explosion shows the dominant blue continuum from the cluster stars shortward of 6000 angstrom as well as strong SN nebular emission lines redward. The integrated spectral energy distribution (SED) of the cluster has been extended into the ultraviolet region by archival XMM-Newton and new Swift observations, and compared with theoretical models. The outer parts of the cluster have been resolved by the Hubble Space Telescope, allowing the construction of a color-magnitude diagram (CMD). The fitting of the cluster SED with theoretical isochrones results in cluster ages distributed between 10 and 40 Myr, depending on the assumed metallicity and the theoretical model family. The isochrone fitting of the CMDs indicates that the resolved part of the cluster consists of stars having a bimodal age distribution: a younger population at similar to 10-16 Myr and an older one at similar to 32-100 Myr. The older population has an age distribution similar to that of the other nearby field stars. This may be explained with the hypothesis that the outskirts of Sandage-96 are contaminated by stars captured from the field during cluster formation. The young age of Sandage-96 and the comparison of its pre and postexplosion SEDs suggest 12 less than or similar to M-prog less than or similar to 20 M-circle dot as the most probable mass range for the progenitor of SN 2004dj. This is consistent with, but perhaps slightly higher than, most of the other Type II-plateau SN progenitor masses determined so far.
C1 [Vinko, J.; Sarneczky, K.; Balog, Z.; Csak, B.] Univ Szeged, Dept Opt & Quantum Elect, H-6720 Szeged, Hungary.
[Vinko, J.] Univ Texas Austin, Dept Astron, Austin, TX 78712 USA.
[Balog, Z.; Misselt, K.] Univ Arizona, Steward Observ, Tucson, AZ 85721 USA.
[Immler, S.] NASA, Goddard Space Flight Ctr, Astrophys Sci Div, Xray Astrophys Lab Code 662, Greenbelt, MD 20771 USA.
[Sugerman, B. E. K.] Goucher Coll, Dept Phys & Astron, Baltimore, MD 21204 USA.
[Brown, P. J.] Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA.
[Szabo, Gy. M.] Univ Szeged, Dept Expt Phys, Szeged, Hungary.
[Csizmadia, Sz.] German Aerosp Ctr, Inst Planetary Res, D-12489 Berlin, Germany.
[Kun, M.] Hungarian Acad Sci, Konkoly Observ, Budapest, Hungary.
[Klagyivik, P.] Eotvos Lorand Univ, Dept Astron, Budapest, Hungary.
[Foley, R. J.; Filippenko, A. V.] Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA.
[Foley, R. J.] Ctr Astrophys, Cambridge, MA 02138 USA.
[Kiss, L. L.] Univ Sydney, Inst Astron, Sch Phys, Sydney, NSW 2006, Australia.
RP Vinko, J (reprint author), Univ Szeged, Dept Opt & Quantum Elect, Dom ter 9, H-6720 Szeged, Hungary.
EM vinko@physx.u-szeged.hu
RI Kiss, Laszlo/A-2539-2008; Szabo, Gyula/A-8310-2012
FU NASA [NAS 5-26555, 1255094]; W. M. Keck Foundation; STScI [GO-10607,
GO-10182]; NSF [AST-0607485, AST-0707769]; Texas Advanced Research
Project grant [AST-0094]; Hungarian OTKA [TS049872]; Swift Science
Center
FX This work was based in part on observations made with the NASA/ESA HST,
obtained from the Data Archive at the Space Telescope Science Institute
(STScI), which is operated by the Association of Universities for
Research in Astronomy, Inc., under NASA contract NAS 5-26555. It is also
based in part on data from the W. M. Keck Observatory, which is operated
as a scientific partnership among the California Institute of
Technology, the University of California, and NASA; the observatory was
made possible by the generous financial support of the W. M. Keck
Foundation. This work was partially supported by NASA through contract
1255094 issued by JPL/Caltech, by NASA/HST grants GO-10607 (B. S.) and
GO-10182 (A. V. F.) from STScI, and by NSF grant AST-0607485 (A. V. F.).
J. V. received support from NSF grant AST-0707769 and Texas Advanced
Research Project grant AST-0094 to J. C. Wheeler, and from Hungarian
OTKA grant TS049872.; We are grateful for the support received from the
Swift Science Center. An anonymous referee provided many useful
suggestions and advice that helped us extend and improve the paper. The
SIMBAD database at CDS, the NASA ADS and NED, and the Canadian Astronomy
Data Centre have been used to access data and references.
NR 57
TC 28
Z9 28
U1 0
U2 4
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 APR 10
PY 2009
VL 695
IS 1
BP 619
EP 635
DI 10.1088/0004-637X/695/1/619
PG 17
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 427KZ
UT WOS:000264779500051
ER
PT J
AU Ogliore, RC
Stone, EC
Leske, RA
Mewaldt, RA
Wiedenbeck, ME
Binns, WR
Israel, MH
von Rosenvinge, TT
de Nolfo, GA
Moskalenko, IV
AF Ogliore, R. C.
Stone, E. C.
Leske, R. A.
Mewaldt, R. A.
Wiedenbeck, M. E.
Binns, W. R.
Israel, M. H.
von Rosenvinge, T. T.
de Nolfo, G. A.
Moskalenko, I. V.
TI THE PHOSPHORUS, SULFUR, ARGON, AND CALCIUM ISOTOPIC COMPOSITION OF THE
GALACTIC COSMIC RAY SOURCE
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE cosmic rays; Galaxy: abundances; ISM: abundances; ISM: bubbles;
supernovae: general
ID SUPERBUBBLE ORIGIN; SUPERNOVA-REMNANTS; STELLAR EVOLUTION; ABUNDANCES;
STARS; MODELS; DUST; NUCLEOSYNTHESIS; PROPAGATION; ELEMENTS
AB Galactic cosmic ray (GCR) measurements of the phosphorus, sulfur, argon, and calcium isotopes made by the Cosmic Ray Isotope Spectrometer aboard the Advanced Composition Explorer are reported over the energy range from similar to 100 to similar to 400 MeV nucleon(-1). The propagation of cosmic rays through the Galaxy and heliosphere is modeled with constraints imposed by measurements. Isotopic source abundance ratios (31)P/(32)S, (34)S/(32)S, (38)Ar/(36)Ar, and (44)Ca/(40)Ca are deduced. The derived (31)P/(32)S ratio is 2.34 +/- 0.34 times larger than the solar system value, lending further credence to the suggestion that refractory elements are enriched in the GCRs due to the sputtering of ions off grains in the cores of superbubbles. By determining the GCR source abundances of argon (a noble gas) and calcium (a refractory), it is determined that material in grains is accelerated to GCR energies a factor of 6.4 +/- 0.3 more efficiently than gas-phase material in this charge range. With this information, the dust fraction of phosphorus and sulfur in the interstellar material that is mixed with stellar ejecta to form the GCR seed material is found to be consistent with astronomical observations.
C1 [Wiedenbeck, M. E.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
[Binns, W. R.; Israel, M. H.] Washington Univ, St Louis, MO 63130 USA.
[von Rosenvinge, T. T.; de Nolfo, G. A.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
[Moskalenko, I. V.] Stanford Univ, HEPL, Stanford, CA 94305 USA.
[Moskalenko, I. V.] Stanford Univ, KIPAC, Stanford, CA 94305 USA.
[Ogliore, R. C.; Stone, E. C.; Leske, R. A.; Mewaldt, R. A.] CALTECH, Pasadena, CA 91125 USA.
RP Ogliore, RC (reprint author), Univ Calif Berkeley, Berkeley Space Sci Lab, 7 Gauss Way, Berkeley, CA 94704 USA.
EM ogliore@ssl.berkeley.edu
RI de Nolfo, Georgia/E-1500-2012; Moskalenko, Igor/A-1301-2007
OI Moskalenko, Igor/0000-0001-6141-458X
FU NASA at the California Institute of Technology [NAG5-12929]; Jet
Propulsion Laboratory; Goddard Space Flight Center; Washington
University; APRA
FX This work was supported by NASA at the California Institute of
Technology (under grant NAG5-12929), the Jet Propulsion Laboratory, the
Goddard Space Flight Center, and Washington University. I. V. M.
acknowledges NASA and APRA grants for partial support.
NR 65
TC 3
Z9 3
U1 1
U2 6
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 APR 10
PY 2009
VL 695
IS 1
BP 666
EP 678
DI 10.1088/0004-637X/695/1/666
PG 13
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 427KZ
UT WOS:000264779500055
ER
PT J
AU Soummer, R
Pueyo, L
Ferrari, A
Aime, C
Sivaramakrishnan, A
Yaitskova, N
AF Soummer, Remi
Pueyo, Laurent
Ferrari, Andre
Aime, Claude
Sivaramakrishnan, Anand
Yaitskova, Natalia
TI APODIZED PUPIL LYOT CORONAGRAPHS FOR ARBITRARY APERTURES. II.
THEORETICAL PROPERTIES AND APPLICATION TO EXTREMELY LARGE TELESCOPES
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE instrumentation: high angular resolution
ID SPHEROIDAL WAVE-FUNCTIONS; EXTRASOLAR GIANT PLANETS; PHASE-MASK
CORONAGRAPH; STELLAR CORONAGRAPH; RECTANGULAR APERTURES;
FOURIER-ANALYSIS; APODIZATION; PRINCIPLE
AB We study the application of Lyot coronagraphy to future Extremely Large Telescopes (ELTs), showing that Apodized Pupil Lyot Coronagraphs enable high-contrast imaging for exoplanet detection and characterization with ELTs. We discuss the properties of the optimal pupil apodizers for this application (generalized prolate spheroidal functions). The case of a circular aperture telescope with a central obstruction is considered in detail, and we discuss the effects of primary mirror segmentation and secondary mirror support structures as a function of the occulting mask size. In most cases where inner working distance is critical, e. g., for exoplanet detection, these additional features do not alter the solutions derived with just the central obstruction, although certain applications such as quasar-host galaxy coronagraphic observations could benefit from designs that explicitly accomodate ELT spider geometries. We illustrate coronagraphic designs for several ELT geometries including ESO/OWL, the Thirty Mirror Telescope, the Giant Magellan Telescope, and describe numerical methods for generating these designs.
C1 [Soummer, Remi] Space Telescope Sci Inst, Baltimore, MD 21218 USA.
[Pueyo, Laurent] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
[Ferrari, Andre; Aime, Claude] Univ Nice Sophia Antipolis, LUAN, F-06108 Nice, France.
[Sivaramakrishnan, Anand] Amer Museum Nat Hist, Dept Astrophys, New York, NY 10024 USA.
[Yaitskova, Natalia] European So Observ, D-85748 Garching, Germany.
EM lpueyo@jpl.nasa.gov; ferrari@unice.fr; aime@unice.fr; anand@amnh.org;
nyaitsko@eso.org
FU Michelson Postdoctoral Fellowship; NASA; AMNH Kalbfleisch; National
Science Fundation [AST-0215793, AST-0334916]; National Science
Foundation Science and Technology Center for Adaptive Optics, managed by
the University of California at Santa Cruz [AST 98-76783]
FX R. S. is supported by a Michelson Postdoctoral Fellowship, under
contract to the Jet Propulsion Laboratory (JPL) funded by NASA. JPL is
managed for NASA by the California Institute of Technology and partially
supported by an AMNH Kalbfleisch Fellowship. This work is based upon
work partially supported by the National Science Fundation: AST-0215793
and AST-0334916 and has also been partially supported by the National
Science Foundation Science and Technology Center for Adaptive Optics,
managed by the University of California at Santa Cruz under cooperative
agreement AST 98-76783.
NR 44
TC 29
Z9 29
U1 0
U2 5
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 APR 10
PY 2009
VL 695
IS 1
BP 695
EP 706
DI 10.1088/0004-637X/695/1/695
PG 12
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 427KZ
UT WOS:000264779500057
ER
PT J
AU Godfrey, LEH
Bicknell, GV
Lovell, JEJ
Jauncey, DL
Gelbord, J
Schwartz, DA
Marshall, HL
Birkinshaw, M
Georganopoulos, M
Murphy, DW
Perlman, ES
Worrall, DM
AF Godfrey, L. E. H.
Bicknell, G. V.
Lovell, J. E. J.
Jauncey, D. L.
Gelbord, J.
Schwartz, D. A.
Marshall, H. L.
Birkinshaw, M.
Georganopoulos, M.
Murphy, D. W.
Perlman, E. S.
Worrall, D. M.
TI A MULTIWAVELENGTH STUDY OF THE HIGH SURFACE BRIGHTNESS HOT SPOT IN PKS
1421-490
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE galaxies: active; galaxies: jets; quasars: individual (PKS 1421-490)
ID X-RAY-EMISSION; MAGNETOSONIC SHOCK-WAVES; POWERFUL RADIO GALAXIES;
ACTIVE GALACTIC NUCLEI; PARTICLE-ACCELERATION; CYGNUS-A; CHANDRA
OBSERVATIONS; PHYSICAL CONDITIONS; RELATIVISTIC JETS; OPTICAL-EMISSION
AB Long Baseline Array imaging of the z = 0.663 broadline radio galaxy PKS 1421-490 reveals a 400 pc diameter high surface brightness hot spot at a projected distance of similar to 40 kpc from the active galactic nucleus. The isotropic X-ray luminosity of the hot spot, L2-10 (keV) = 3 x 10(44) ergs s(-1), is comparable to the isotropic X-ray luminosity of the entire X-ray jet of PKS 0637-752, and the peak radio surface brightness is hundreds of times greater than that of the brightest hot spot in Cygnus A. We model the radio to X-ray spectral energy distribution using a one-zone synchrotron self-Compton model with a near equipartition magnetic field strength of 3 mG. There is a strong brightness asymmetry between the approaching and receding hotspots and the hot spot spectrum remains flat (alpha approximate to 0.5) well beyond the predicted cooling break for a 3 mG magnetic field, indicating that the hotspot emission may be Doppler beamed. A high plasma velocity beyond the terminal jet shock could be the result of a dynamically important magnetic field in the jet. There is a change in the slope of the hotspot radio spectrum at GHz frequencies, which we model by incorporating a cutoff in the electron energy distribution at gamma(min) approximate to 650, with higher values implied if the hotspot emission is Doppler beamed. We show that a sharp decrease in the electron number density below a Lorentz factor of 650 would arise from the dissipation of bulk kinetic energy in an electron/proton jet with a Lorentz factor Gamma(jet) greater than or similar to 5.
C1 [Godfrey, L. E. H.; Bicknell, G. V.] Australian Natl Univ, Res Sch Astron & Astrophys, Weston, ACT 2611, Australia.
[Godfrey, L. E. H.; Lovell, J. E. J.; Jauncey, D. L.] CSIRO, Australia Telescope Natl Facil, Epping, NSW 2121, Australia.
[Lovell, J. E. J.] CSIRO, Sydney, NSW 2070, Australia.
[Lovell, J. E. J.] Univ Tasmania, Sch Math & Phys, Hobart, Tas 7001, Australia.
[Schwartz, D. A.; Birkinshaw, M.; Worrall, D. M.] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA.
[Marshall, H. L.] MIT, Kavli Inst Astrophys & Space Res, Cambridge, MA 02139 USA.
[Birkinshaw, M.; Worrall, D. M.] Univ Bristol, Dept Phys, Bristol BS8 1TL, Avon, England.
[Georganopoulos, M.; Perlman, E. S.] Univ Maryland Baltimore Cty, Joint Ctr Astrophys, Dept Phys, Baltimore, MD 21250 USA.
[Georganopoulos, M.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
[Murphy, D. W.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
RP Godfrey, LEH (reprint author), Australian Natl Univ, Res Sch Astron & Astrophys, Cotter Rd, Weston, ACT 2611, Australia.
EM lgodfrey@mso.anu.edu.au
RI Godfrey, Leith/B-5283-2013
FU Commonwealth of Australia for operation as a National Facility managed
by CSIRO; National Aeronautics and Space Administration; National
Science Foundation
FX L. E. H. G. thanks John Kirk for very helpful discussions on the topic
of particle acceleration, and Emil Lenc for supplying the cordump patch
for DIFMAP. L. E. H. G. also thanks the Grote Reber Foundation for
financial support. The Australia Telescope Compact Array and Long
Baseline Array are part of the Australia Telescope which is funded by
the Commonwealth of Australia for operation as a National Facility
managed by CSIRO. This paper includes data gathered with the 6.5 meter
Magellan Telescopes located at Las Campanas Observatory, Chile. This
publication makes use of data products from the Two Micron All Sky
Survey, which is a joint project of the University of Massachusetts and
the Infrared Processing and Analysis Center/California Institute of
Technology, funded by the National Aeronautics and Space Administration
and the National Science Foundation.
NR 66
TC 26
Z9 26
U1 0
U2 2
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 APR 10
PY 2009
VL 695
IS 1
BP 707
EP 723
DI 10.1088/0004-637X/695/1/707
PG 17
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 427KZ
UT WOS:000264779500058
ER
PT J
AU Haas, M
Willner, SP
Heymann, F
Ashby, MLN
Fazio, GG
Wilkes, BJ
Chini, R
Siebenmorgen, R
Stern, D
AF Haas, Martin
Willner, S. P.
Heymann, Frank
Ashby, M. L. N.
Fazio, G. G.
Wilkes, Belinda J.
Chini, Rolf
Siebenmorgen, Ralf
Stern, Daniel
TI CLUSTERING OF RED GALAXIES AROUND THE z=1.53 QUASAR 3C 270.1
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE galaxies: clusters: individual (3C270.1); infrared: galaxies; quasars:
general
ID SPITZER-SPACE-TELESCOPE; LYMAN-BREAK GALAXIES; RADIO GALAXIES;
DISCOVERY; OBJECTS; IRAC; PROTOCLUSTER; OVERDENSITY; PHOTOMETRY;
SOFTWARE
AB In the paradigm of hierarchical galaxy formation, luminous radio galaxies mark mass assembly peaks that should contain clusters of galaxies. Observations of the z = 1.53 quasar 3C 270.1 with the Spitzer Space Telescope at 3.6-24 mu m and with the 6.5 m MMT in the z' and Y bands allow the detection of potential cluster members via photometric redshifts. Compared with nearby control fields, there is an excess of similar to 11 extremely red objects (EROs) at 1.33 <= z(phot) <= 1.73, consistent with a protocluster around the quasar. The spectral energy distributions of 3/4 of the EROs are better fitted with passive elliptical galaxies than with dust-reddened starbursts, and of four sources well detected on an archival Hubble Space Telescope (HST) snapshot image, all have undisturbed morphologies. However, one ERO, not covered by the HST image, is a double source with 0.'' 8 separation on the z' image and a marginal (2 sigma) 24 mu m detection indicating a dust-enshrouded starburst. The EROs are more luminous than L(star) (H = -23.6 AB mag at z approximate to 1.5).
C1 [Haas, Martin; Heymann, Frank; Chini, Rolf] Ruhr Univ Bochum, Inst Astron, D-44801 Bochum, Germany.
[Willner, S. P.; Ashby, M. L. N.; Fazio, G. G.; Wilkes, Belinda J.] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA.
[Heymann, Frank; Siebenmorgen, Ralf] European So Observ, D-85748 Garching, Germany.
[Stern, Daniel] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
RP Haas, M (reprint author), Ruhr Univ Bochum, Inst Astron, Univ Str 150, D-44801 Bochum, Germany.
EM haas@astro.rub.de
OI Wilkes, Belinda/0000-0003-1809-2364
FU NASA; Nordrhein-Westfalische Akademie der Wissenschaften
FX This work is based in part on observations made with the Spitzer Space
Telescope, which is operated by the Jet Propulsion Laboratory (JPL),
Caltech under a contract with NASA. Support for this work was provided
by NASA through an award issued by JPL/Caltech. The ground-based
observations reported here were obtained at the MMT Observatory, a joint
facility of the Smithsonian Institution and the University of Arizona.
This research has made use of the NASA/IPAC Extragalactic Database (NED)
and of the Sloan Digital Sky Survey (SDSS DR6). We thank Dominik Bomans
and Hans Hippelein for valuable discussions and comments on the
manuscript, and an anonymous referee for the constructive, critical
report. M. H. is supported by the Nordrhein-Westfalische Akademie der
Wissenschaften.
NR 40
TC 4
Z9 4
U1 0
U2 4
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 APR 10
PY 2009
VL 695
IS 1
BP 724
EP 731
DI 10.1088/0004-637X/695/1/724
PG 8
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 427KZ
UT WOS:000264779500059
ER
PT J
AU Abdo, AA
Ackermann, M
Atwood, WB
Baldini, L
Ballet, J
Barbiellini, G
Baring, MG
Bastieri, D
Baughman, BM
Bechtol, K
Bellazzini, R
Berenji, B
Bloom, ED
Bonamente, E
Borgland, AW
Bregeon, J
Brez, A
Brigida, M
Bruel, P
Burnett, TH
Caliandro, GA
Cameron, RA
Caraveo, PA
Casandjian, JM
Cecchi, C
Charles, E
Chekhtman, A
Cheung, CC
Chiang, J
Ciprini, S
Claus, R
Cohen-Tanugi, J
Cominsky, LR
Conrad, J
Dermer, CD
de Angelis, A
de Palma, F
Digel, SW
Donato, D
Dormody, M
Silva, EDE
Drell, PS
Dubois, R
Dumora, D
Edmonds, Y
Farnier, C
Favuzzi, C
Fleury, P
Focke, WB
Frailis, M
Fukazawa, Y
Funk, S
Fusco, P
Gargano, F
Gasparrini, D
Gehrels, N
Germani, S
Giebels, B
Giglietto, N
Giordano, F
Glanzman, T
Godfrey, G
Grenier, IA
Grondin, MH
Grove, JE
Guillemot, L
Guiriec, S
Harding, AK
Hayashida, M
Hays, E
Hughes, RE
Johannesson, G
Johnson, AS
Johnson, RP
Johnson, TJ
Johnson, WN
Johnston, S
Kamae, T
Katagiri, H
Kataoka, J
Kawai, N
Kerr, M
Knodlseder, J
Komin, N
Kramer, M
Kuehn, F
Kuss, M
Latronico, L
Lee, SH
Lemoine-Goumard, M
Longo, F
Loparco, F
Lott, B
Lovellette, MN
Lubrano, P
Makeev, A
Marelli, M
Mazziotta, MN
McConville, W
McEnery, JE
Meurer, C
Michelson, PF
Mitthumsiri, W
Mizuno, T
Moiseev, AA
Monte, C
Monzani, ME
Morselli, A
Moskalenko, IV
Murgia, S
Nolan, PL
Nuss, E
Ohsugi, T
Omodei, N
Orlando, E
Ormes, JF
Paneque, D
Panetta, JH
Parent, D
Pepe, M
Pesce-Rollins, M
Piron, F
Porter, TA
Raino, S
Rando, R
Razzano, M
Reimer, A
Reimer, O
Reposeur, T
Ritz, S
Rochester, LS
Rodriguez, AY
Romani, RW
Roth, M
Ryde, F
Sadrozinski, HFW
Sanchez, D
Sander, A
Parkinson, PMS
Sgro, C
Siskind, EJ
Smith, DA
Smith, PD
Spandre, G
Spinelli, P
Starck, JL
Strickman, MS
Suson, DJ
Tajima, H
Takahashi, H
Tanaka, T
Thayer, JB
Thayer, JG
Thompson, DJ
Thorsett, SE
Tibaldo, L
Torres, DF
Tosti, G
Tramacere, A
Uchiyama, Y
Usher, TL
Van Etten, A
Vilchez, N
Vitale, V
Waite, AP
Watters, K
Wood, KS
Ylinen, T
Ziegler, M
Hobbs, G
Keith, M
Manchester, RN
Weltevrede, P
AF Abdo, A. A.
Ackermann, M.
Atwood, W. B.
Baldini, L.
Ballet, J.
Barbiellini, G.
Baring, M. G.
Bastieri, D.
Baughman, B. M.
Bechtol, K.
Bellazzini, R.
Berenji, B.
Bloom, E. D.
Bonamente, E.
Borgland, A. W.
Bregeon, J.
Brez, A.
Brigida, M.
Bruel, P.
Burnett, T. H.
Caliandro, G. A.
Cameron, R. A.
Caraveo, P. A.
Casandjian, J. M.
Cecchi, C.
Charles, E.
Chekhtman, A.
Cheung, C. C.
Chiang, J.
Ciprini, S.
Claus, R.
Cohen-Tanugi, J.
Cominsky, L. R.
Conrad, J.
Dermer, C. D.
de Angelis, A.
de Palma, F.
Digel, S. W.
Donato, D.
Dormody, M.
do Couto e Silva, E.
Drell, P. S.
Dubois, R.
Dumora, D.
Edmonds, Y.
Farnier, C.
Favuzzi, C.
Fleury, P.
Focke, W. B.
Frailis, M.
Fukazawa, Y.
Funk, S.
Fusco, P.
Gargano, F.
Gasparrini, D.
Gehrels, N.
Germani, S.
Giebels, B.
Giglietto, N.
Giordano, F.
Glanzman, T.
Godfrey, G.
Grenier, I. A.
Grondin, M. -H.
Grove, J. E.
Guillemot, L.
Guiriec, S.
Harding, A. K.
Hayashida, M.
Hays, E.
Hughes, R. E.
Johannesson, G.
Johnson, A. S.
Johnson, R. P.
Johnson, T. J.
Johnson, W. N.
Johnston, S.
Kamae, T.
Katagiri, H.
Kataoka, J.
Kawai, N.
Kerr, M.
Knoedlseder, J.
Komin, N.
Kramer, M.
Kuehn, F.
Kuss, M.
Latronico, L.
Lee, S. -H.
Lemoine-Goumard, M.
Longo, F.
Loparco, F.
Lott, B.
Lovellette, M. N.
Lubrano, P.
Makeev, A.
Marelli, M.
Mazziotta, M. N.
McConville, W.
McEnery, J. E.
Meurer, C.
Michelson, P. F.
Mitthumsiri, W.
Mizuno, T.
Moiseev, A. A.
Monte, C.
Monzani, M. E.
Morselli, A.
Moskalenko, I. V.
Murgia, S.
Nolan, P. L.
Nuss, E.
Ohsugi, T.
Omodei, N.
Orlando, E.
Ormes, J. F.
Paneque, D.
Panetta, J. H.
Parent, D.
Pepe, M.
Pesce-Rollins, M.
Piron, F.
Porter, T. A.
Raino, S.
Rando, R.
Razzano, M.
Reimer, A.
Reimer, O.
Reposeur, T.
Ritz, S.
Rochester, L. S.
Rodriguez, A. Y.
Romani, R. W.
Roth, M.
Ryde, F.
Sadrozinski, H. F. -W.
Sanchez, D.
Sander, A.
Parkinson, P. M. Saz
Sgro, C.
Siskind, E. J.
Smith, D. A.
Smith, P. D.
Spandre, G.
Spinelli, P.
Starck, J. -L.
Strickman, M. S.
Suson, D. J.
Tajima, H.
Takahashi, H.
Tanaka, T.
Thayer, J. B.
Thayer, J. G.
Thompson, D. J.
Thorsett, S. E.
Tibaldo, L.
Torres, D. F.
Tosti, G.
Tramacere, A.
Uchiyama, Y.
Usher, T. L.
Van Etten, A.
Vilchez, N.
Vitale, V.
Waite, A. P.
Watters, K.
Wood, K. S.
Ylinen, T.
Ziegler, M.
Hobbs, G.
Keith, M.
Manchester, R. N.
Weltevrede, P.
TI DISCOVERY OF PULSED gamma-RAYS FROM THE YOUNG RADIO PULSAR PSR
J1028-5819 WITH THE FERMI LARGE AREA TELESCOPE
SO ASTROPHYSICAL JOURNAL LETTERS
LA English
DT Article
DE pulsars: general; stars: neutron
ID TIME-DIFFERENCING TECHNIQUE; SPACE TELESCOPE; RADIATION; EMISSION;
CATALOG; SEARCH; GAPS
AB Radio pulsar PSR J1028-5819 was recently discovered in a high-frequency search (at 3.1 GHz) in the error circle of the Energetic Gamma-Ray Experiment Telescope (EGRET) source 3EG J1027-5817. The spin-down power of this young pulsar is great enough to make it very likely the counterpart for the EGRET source. We report here the discovery of gamma-ray pulsations from PSR J1028-5819 in early observations by the Large Area Telescope (LAT) on the Fermi Gamma-Ray Space Telescope. The gamma-ray light curve shows two sharp peaks having phase separation of 0.460 +/- 0.004, trailing the very narrow radio pulse by 0.200 +/- 0.003 in phase, very similar to that of other known gamma-ray pulsars. The measured gamma-ray flux gives an efficiency for the pulsar of similar to 10-20% (for outer magnetosphere beam models). No evidence of a surrounding pulsar wind nebula is seen in the current Fermi data but limits on associated emission are weak because the source lies in a crowded region with high background emission. However, the improved angular resolution afforded by the LAT enables the disentanglement of the previous COS-B and EGRET source detections into at least two distinct sources, one of which is now identified as PSR J1028-5819.
C1 [Cheung, C. C.; Donato, D.; Gehrels, N.; Harding, A. K.; Hays, E.; Johnson, T. J.; McConville, W.; McEnery, J. E.; Ritz, S.; Thompson, D. J.] NASA, Goddard Space Flight Ctr, CRESST, Greenbelt, MD 20771 USA.
[Abdo, A. A.; Chekhtman, A.; Dermer, C. D.; Grove, J. E.; Johnson, W. N.; Lovellette, M. N.; Makeev, A.; Strickman, M. S.; Wood, K. S.] Naval Res Lab, Div Space Sci, Washington, DC 20375 USA.
[Ackermann, M.; Bechtol, K.; Berenji, B.; Bloom, E. D.; Borgland, A. W.; Cameron, R. A.; Charles, E.; Chiang, J.; Claus, R.; Digel, S. W.; do Couto e Silva, E.; Drell, P. S.; Dubois, R.; Edmonds, Y.; Focke, W. B.; Funk, S.; Glanzman, T.; Godfrey, G.; Hayashida, M.; Johannesson, G.; Johnson, A. S.; Kamae, T.; Lee, S. -H.; Michelson, P. F.; Mitthumsiri, W.; Monzani, M. E.; Moskalenko, I. V.; Murgia, S.; Nolan, P. L.; Paneque, D.; Panetta, J. H.; Reimer, A.; Reimer, O.; Rochester, L. S.; Romani, R. W.; Tajima, H.; Tanaka, T.; Thayer, J. B.; Thayer, J. G.; Tramacere, A.; Uchiyama, Y.; Usher, T. L.; Van Etten, A.; Waite, A. P.; Watters, K.] Stanford Univ, W W Hansen Expt Phys Lab, Kavli Inst Particle Astrophys & Cosmol, Dept Phys, Stanford, CA 94305 USA.
[Ackermann, M.; Bechtol, K.; Berenji, B.; Bloom, E. D.; Borgland, A. W.; Cameron, R. A.; Charles, E.; Chiang, J.; Claus, R.; Digel, S. W.; do Couto e Silva, E.; Drell, P. S.; Dubois, R.; Edmonds, Y.; Focke, W. B.; Funk, S.; Glanzman, T.; Godfrey, G.; Hayashida, M.; Johannesson, G.; Johnson, A. S.; Kamae, T.; Lee, S. -H.; Michelson, P. F.; Mitthumsiri, W.; Monzani, M. E.; Moskalenko, I. V.; Murgia, S.; Nolan, P. L.; Paneque, D.; Panetta, J. H.; Reimer, A.; Reimer, O.; Rochester, L. S.; Romani, R. W.; Tajima, H.; Tanaka, T.; Thayer, J. B.; Thayer, J. G.; Tramacere, A.; Uchiyama, Y.; Usher, T. L.; Van Etten, A.; Waite, A. P.; Watters, K.] Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94305 USA.
[Atwood, W. B.; Dormody, M.; Johnson, R. P.; Porter, T. A.; Sadrozinski, H. F. -W.; Parkinson, P. M. Saz; Thorsett, S. E.; Ziegler, M.] Univ Calif Santa Cruz, Santa Cruz Inst Particle Phys, Dept Phys, Santa Cruz, CA 95064 USA.
[Atwood, W. B.; Dormody, M.; Johnson, R. P.; Porter, T. A.; Sadrozinski, H. F. -W.; Parkinson, P. M. Saz; Thorsett, S. E.; Ziegler, M.] Univ Calif Santa Cruz, Dept Astron & Astrophys, Santa Cruz, CA 95064 USA.
[Baldini, L.; Bellazzini, R.; Bregeon, J.; Brez, A.; Kuss, M.; Latronico, L.; Omodei, N.; Pesce-Rollins, M.; Razzano, M.; Sgro, C.; Spandre, G.] Ist Nazl Fis Nucl, Sez Pisa, I-56127 Pisa, Italy.
[Ballet, J.; Casandjian, J. M.; Grenier, I. A.; Komin, N.; Starck, J. -L.] Univ Paris, CEA Saclay, Serv Astrophys, Lab AIM,CEA,IRFU,CNRS, F-91191 Gif Sur Yvette, France.
[Barbiellini, G.; Longo, F.] Ist Nazl Fis Nucl, Sez Trieste, I-34127 Trieste, Italy.
[Barbiellini, G.; Longo, F.] Univ Trieste, Dipartmento Fis, I-34127 Trieste, Italy.
[Baring, M. G.] Rice Univ, Dept Phys & Astron, Houston, TX 77251 USA.
[Bastieri, D.; Rando, R.; Tibaldo, L.] Ist Nazl Fis Nucl, Sez Padova, I-35131 Padua, Italy.
[Bastieri, D.; Rando, R.; Tibaldo, L.] Univ Padua, Dipartimento Fis G Galilei, I-35131 Padua, Italy.
[Baughman, B. M.; Hughes, R. E.; Kuehn, F.; Sander, A.; Smith, P. D.] Ohio State Univ, Dept Phys, Ctr Cosmol & Astro Particle Phys, Columbus, OH 43210 USA.
[Bonamente, E.; Cecchi, C.; Ciprini, S.; Germani, S.; Lubrano, P.; Pepe, M.; Tosti, G.] Ist Nazl Fis Nucl, Sez Perugia, I-06123 Perugia, Italy.
[Bonamente, E.; Cecchi, C.; Ciprini, S.; Germani, S.; Lubrano, P.; Pepe, M.; Tosti, G.] Univ Perugia, Dipartimento Fis, I-06123 Perugia, Italy.
[Brigida, M.; Caliandro, G. A.; de Palma, F.; Favuzzi, C.; Fusco, P.; Giglietto, N.; Giordano, F.; Loparco, F.; Monte, C.; Raino, S.; Spinelli, P.] Univ Politecn Bari, Dipartimento Fis M Merlin, I-70126 Bari, Italy.
[Brigida, M.; Caliandro, G. A.; de Palma, F.; Favuzzi, C.; Fusco, P.; Gargano, F.; Giglietto, N.; Giordano, F.; Loparco, F.; Mazziotta, M. N.; Monte, C.; Raino, S.] Ist Nazl Fis Nucl, Sez Bari, I-70126 Bari, Italy.
[Bruel, P.; Fleury, P.; Giebels, B.; Sanchez, D.] Ecole Polytech, CNRS, IN2P3, Lab Leprince Ringuet, F-91128 Palaiseau, France.
[Burnett, T. H.; Kerr, M.; Roth, M.] Univ Washington, Dept Phys, Seattle, WA 98195 USA.
[Caraveo, P. A.; Marelli, M.] INAF Ist Astrofis Spaziale & Fis Cosm, I-20133 Milan, Italy.
[Chekhtman, A.; Makeev, A.] George Mason Univ, Fairfax, VA 22030 USA.
[Cohen-Tanugi, J.; Farnier, C.; Guiriec, S.; Komin, N.; Nuss, E.; Piron, F.] Univ Montpellier 2, CNRS, IN2P3, Lab Phys Theor & Astroparticules, Montpellier, France.
[Cominsky, L. R.] Sonoma State Univ, Dept Phys & Astron, Rohnert Pk, CA 94928 USA.
[Conrad, J.; Meurer, C.; Ryde, F.; Ylinen, T.] Oskar Klein Ctr Cosmo Particle Phys, SE-10691 Stockholm, Sweden.
[Conrad, J.; Ryde, F.; Ylinen, T.] Royal Inst Technol, Dept Phys, KTH, SE-10691 Stockholm, Sweden.
[Conrad, J.; Meurer, C.] Stockholm Univ, Dept Phys, SE-10691 Stockholm, Sweden.
[de Angelis, A.; Frailis, M.] Univ Udine, Dipartimento Fis, I-33100 Udine, Italy.
[de Angelis, A.; Frailis, M.] Ist Nazl Fis Nucl, Sez Trieste, Grp Collegato Udine, I-33100 Udine, Italy.
[Dumora, D.; Grondin, M. -H.; Guillemot, L.; Lemoine-Goumard, M.; Lott, B.; Parent, D.; Reposeur, T.; Smith, D. A.] CEN Bordeaux Gradignan, CNRS, IN2P3, UMR 5797, F-33175 Gradignan, France.
[Dumora, D.; Grondin, M. -H.; Guillemot, L.; Lemoine-Goumard, M.; Lott, B.; Parent, D.; Reposeur, T.; Smith, D. A.] Univ Bordeaux, CEN Bordeaux Gradignan, UMR 5797, F-33175 Gradignan, France.
[Fukazawa, Y.; Katagiri, H.; Mizuno, T.; Ohsugi, T.; Takahashi, H.] Hiroshima Univ, Dept Phys Sci, Higashihiroshima 7398526, Japan.
[Fukazawa, Y.; Katagiri, H.; Mizuno, T.; Ohsugi, T.; Takahashi, H.] Hiroshima Univ, Hiroshima Astrophys Sci Ctr, Higashihiroshima 7398526, Japan.
[Gasparrini, D.] ASI, Sci Data Ctr, I-00044 Frascati, Roma, Italy.
[Gehrels, N.; Johnson, T. J.; Ritz, S.] Univ Maryland, College Pk, MD 20742 USA.
[Johnston, S.; Hobbs, G.; Keith, M.; Manchester, R. N.; Weltevrede, P.] CSIRO, Australia Telescope Natl Facil, Epping, NSW 1710, Australia.
[Kataoka, J.; Kawai, N.] Tokyo Inst Technol, Dept Phys, Tokyo 1528551, Japan.
[Kawai, N.] RIKEN, Inst Phys & Chem Res, Cosm Radiat Lab, Wako, Saitama 3510198, Japan.
[Knoedlseder, J.; Vilchez, N.] CNR, SUPS 47, Ctr Etud Spatiale Rayonnements, F-31028 Toulouse 4, France.
[Kramer, M.] Univ Manchester, Jodrell Bank, Ctr Astrophys, Manchester M13 9PL, Lancs, England.
[Morselli, A.; Vitale, V.] Ist Nazl Fis Nucl, Sez Roma Tor Vergata, I-00133 Rome, Italy.
[Orlando, E.] Max Planck Inst Extraterr Phys, D-85748 Garching, Germany.
[Ormes, J. F.] Univ Denver, Dept Phys & Astron, Denver, CO 80208 USA.
[Rodriguez, A. Y.; Torres, D. F.] CSIC, IEEC, Inst Ciencies Espai, Barcelona 08193, Spain.
[Siskind, E. J.] NYCB Real Time Comp Inc, Lattingtown, NY 11560 USA.
[Suson, D. J.] Purdue Univ Calumet, Dept Chem & Phys, Hammond, IN 46323 USA.
[Torres, D. F.] ICREA, Barcelona, Spain.
[Tramacere, A.] CIFS, I-10133 Turin, Italy.
[Vitale, V.] Univ Roma Tor Vergata, Dipartimento Fis, I-00133 Rome, Italy.
[Ylinen, T.] Univ Kalmar, Sch Pure & Appl Nat Sci, SE-39182 Kalmar, Sweden.
RP Harding, AK (reprint author), NASA, Goddard Space Flight Ctr, CRESST, Greenbelt, MD 20771 USA.
EM ahardingx@yahoo.com; Tyrel.J.Johnson@nasa.gov
RI Nolan, Patrick/A-5582-2009; De Angelis, Alessandro/B-5372-2009; Starck,
Jean-Luc/D-9467-2011; Thompson, David/D-2939-2012; Harding,
Alice/D-3160-2012; Gehrels, Neil/D-2971-2012; McEnery,
Julie/D-6612-2012; Baldini, Luca/E-5396-2012; lubrano,
pasquale/F-7269-2012; Kuss, Michael/H-8959-2012; giglietto,
nicola/I-8951-2012; Morselli, Aldo/G-6769-2011; Tosti, Gino/E-9976-2013;
Rando, Riccardo/M-7179-2013; Komin, Nukri/J-6781-2015; Hays,
Elizabeth/D-3257-2012; Johnson, Neil/G-3309-2014; Reimer,
Olaf/A-3117-2013; Funk, Stefan/B-7629-2015; Johannesson,
Gudlaugur/O-8741-2015; Gargano, Fabio/O-8934-2015; Loparco,
Francesco/O-8847-2015; Moskalenko, Igor/A-1301-2007; Mazziotta, Mario
/O-8867-2015; Sgro, Carmelo/K-3395-2016; Torres, Diego/O-9422-2016;
Orlando, E/R-5594-2016;
OI Starck, Jean-Luc/0000-0003-2177-7794; Thompson,
David/0000-0001-5217-9135; lubrano, pasquale/0000-0003-0221-4806;
giglietto, nicola/0000-0002-9021-2888; Morselli,
Aldo/0000-0002-7704-9553; Giordano, Francesco/0000-0002-8651-2394;
Thorsett, Stephen/0000-0002-2025-9613; SPINELLI,
Paolo/0000-0001-6688-8864; De Angelis, Alessandro/0000-0002-3288-2517;
Frailis, Marco/0000-0002-7400-2135; Caraveo,
Patrizia/0000-0003-2478-8018; Komin, Nukri/0000-0003-3280-0582; Reimer,
Olaf/0000-0001-6953-1385; Funk, Stefan/0000-0002-2012-0080; Johannesson,
Gudlaugur/0000-0003-1458-7036; Gargano, Fabio/0000-0002-5055-6395;
Loparco, Francesco/0000-0002-1173-5673; Moskalenko,
Igor/0000-0001-6141-458X; Mazziotta, Mario /0000-0001-9325-4672; Torres,
Diego/0000-0002-1522-9065; Rando, Riccardo/0000-0001-6992-818X; Sgro',
Carmelo/0000-0001-5676-6214
FU Istituto Nazionale di Astrofisica in Italy; K. A. Wallenberg Foundation
in Sweden
FX Additional support for science analysis during the operations phase from
the following agencies is also gratefully acknowledged: the Istituto
Nazionale di Astrofisica in Italy and the K. A. Wallenberg Foundation in
Sweden for providing a grant in support of a Royal Swedish Academy of
Sciences Research fellowship for J.C.; The Parkes radio telescope is
part of the Australia Telescope which is funded by the Commonwealth of
Australia for operation as a National Facility managed by the CSIRO.
NR 26
TC 30
Z9 31
U1 0
U2 1
PU IOP PUBLISHING LTD
PI BRISTOL
PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND
SN 2041-8205
EI 2041-8213
J9 ASTROPHYS J LETT
JI Astrophys. J. Lett.
PD APR 10
PY 2009
VL 695
IS 1
BP L72
EP L77
DI 10.1088/0004-637X/695/1/L72
PG 6
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 424BE
UT WOS:000264539700016
ER
PT J
AU Catelan, M
Grundahl, F
Sweigart, AV
Valcarce, AAR
Cortes, C
AF Catelan, M.
Grundahl, F.
Sweigart, A. V.
Valcarce, A. A. R.
Cortes, C.
TI CONSTRAINTS ON HELIUM ENHANCEMENT IN THE GLOBULAR CLUSTER M3 (NGC 5272):
THE HORIZONTAL BRANCH TEST
SO ASTROPHYSICAL JOURNAL LETTERS
LA English
DT Article
DE globular clusters: general; globular clusters: individual (M3=NGC 5272,
M13=NGC 6205); Hertzsprung-Russell diagram; stars: abundances; stars:
horizontal-branch
ID MAIN-SEQUENCE STARS; METAL-POOR STARS; OMEGA-CENTAURI; RR-LYRAE;
ABUNDANCES; METALLICITIES; SYSTEM; MASS; AGE; POPULATIONS
AB It has recently been suggested that the presence of multiple populations showing various amounts of helium enhancement is the rule, rather than the exception, among globular star clusters. An important prediction of this helium enhancement scenario is that the helium-enhanced blue horizontal branch (HB) stars should be brighter than the red HB stars which are not helium enhanced. In this Letter, we test this prediction in the case of the Galactic globular cluster M3 (NGC 5272), for which the helium-enhancement scenario predicts helium enhancements of greater than or similar to 0.02 in virtually all blue HB stars. Using high-precision Stromgren photometry and spectroscopic gravities for blue HB stars, we find that any helium enhancement among most of the cluster's blue HB stars is very likely less than 0.01, thus ruling out the much higher helium enhancements that have been proposed in the literature.
C1 [Catelan, M.; Valcarce, A. A. R.; Cortes, C.] Pontificia Univ Catolica Chile, Dept Astron & Astrofis, Santiago 7820436, Chile.
[Catelan, M.] Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA.
[Grundahl, F.] Aarhus Univ, Dept Phys & Astron, DK-8000 Aarhus, Denmark.
[Sweigart, A. V.] NASA, Goddard Space Flight Ctr, Explorat Universe Div, Greenbelt, MD 20771 USA.
[Cortes, C.] Univ Fed Rio Grande do Norte, Dept Fis Teor Expt, BR-59072970 Natal, RN, Brazil.
RP Catelan, M (reprint author), Pontificia Univ Catolica Chile, Dept Astron & Astrofis, Av Vicuna Mackenna 4860, Santiago 7820436, Chile.
FU Proyecto Basal [PFB-06/2007]; FONDAP Centro de Astrofisica [15010003];
Proyecto FONDECYT Regular [1071002]; John Simon Guggenheim Memorial
Foundation Fellowship; Carlsberg Foundation; Danish AsteroSeismology
Centre at Aarhus University; Danish National Research Council
FX We thank an anonymous referee for some helpful comments, and D. A.
VandenBerg and S. Moehler for some enlightening discussions. Support for
M. C. is provided by Proyecto Basal PFB-06/2007, by FONDAP Centro de
Astrofisica 15010003, by Proyecto FONDECYT Regular # 1071002, and by a
John Simon Guggenheim Memorial Foundation Fellowship. F. G. acknowledges
support from the Carlsberg Foundation and the Danish AsteroSeismology
Centre at Aarhus University, and support from the Danish National
Research Council to the Project "Stars: Central engines to the evolution
of the Universe".
NR 43
TC 34
Z9 34
U1 0
U2 2
PU IOP PUBLISHING LTD
PI BRISTOL
PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND
J9 ASTROPHYS J LETT
JI Astrophys. J. Lett.
PD APR 10
PY 2009
VL 695
IS 1
BP L97
EP L102
DI 10.1088/0004-637X/695/1/L97
PG 6
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 424BE
UT WOS:000264539700021
ER
PT J
AU Hamaguchi, K
Corcoran, MF
Ezoe, Y
Townsley, L
Broos, P
Gruendl, R
Vaidya, K
White, SM
Strohmayer, T
Petre, R
Chu, YH
AF Hamaguchi, Kenji
Corcoran, Michael F.
Ezoe, Yuichiro
Townsley, Leisa
Broos, Patrick
Gruendl, Robert
Vaidya, Kaushar
White, Stephen M.
Strohmayer, Tod
Petre, Rob
Chu, You-Hua
TI A SMOKING GUN IN THE CARINA NEBULA
SO ASTROPHYSICAL JOURNAL LETTERS
LA English
DT Article
DE ISM: bubbles; stars: evolution; stars: formation; stars: neutron;
supernova remnants; X-rays: stars
ID X-RAY EMISSION; ETA-CARINAE; XMM-NEWTON; MASSIVE STARS; NEUTRON-STAR;
MAGNETIC-FIELDS; ORION NEBULA; SPECTROSCOPY; PROGENITOR; TELESCOPE
AB The Carina Nebula is one of the youngest, most active sites of massive star formation in our Galaxy. In this nebula, we have discovered a bright X-ray source that has persisted for similar to 30 years. The soft X-ray spectrum, consistent with kT similar to 128 eV blackbody radiation with mild extinction, and no counterpart in the near- and mid-infrared wavelengths indicates that it is a similar to 10(6) year old neutron star housed in the Carina Nebula. Current star formation theory does not suggest that the progenitors of the neutron star and massive stars in the Carina Nebula, in particular. Car, are coeval. This result suggests that the Carina Nebula experienced at least two major episodes of massive star formation. The neutron star may be responsible for remnants of high-energy activity seen in multiple wavelengths.
C1 [Hamaguchi, Kenji; Corcoran, Michael F.] NASA, Goddard Space Flight Ctr, CRESST, Greenbelt, MD 20771 USA.
[Hamaguchi, Kenji; Corcoran, Michael F.] NASA, Goddard Space Flight Ctr, Xray Astrophys Lab, Greenbelt, MD 20771 USA.
[Hamaguchi, Kenji] Univ Maryland, Dept Phys, Baltimore, MD 21250 USA.
[Corcoran, Michael F.] Univ Space Res Assoc, Columbia, MD 21044 USA.
[Ezoe, Yuichiro] Tokyo Metropolitan Univ, Tokyo 1920397, Japan.
[Townsley, Leisa; Broos, Patrick] Penn State Univ, Dept Astron & Astrophys, Davey Lab 525, University Pk, PA 16802 USA.
[Gruendl, Robert; Vaidya, Kaushar; Chu, You-Hua] Univ Illinois, Dept Astron, Urbana, IL 61801 USA.
[White, Stephen M.] Univ Maryland, Dept Astron, College Pk, MD 20742 USA.
[Strohmayer, Tod; Petre, Rob] NASA, Goddard Space Flight Ctr, Astrophys Sci Div, Greenbelt, MD 20771 USA.
RP Hamaguchi, K (reprint author), NASA, Goddard Space Flight Ctr, CRESST, Greenbelt, MD 20771 USA.
FU NASA's Astrobiology Institute [RTOP 344-53-51]
FX We are grateful to T. R. Gull, K. E. Nielsen, S. Drake, K. Mukai, M.
Ishida, C. Markwardt, and the anonymous referee for useful comments.
This work was performed while K. H. was supported by NASA's Astrobiology
Institute (RTOP 344-53-51) to the Goddard Center for Astrobiology. This
research has made use of data and softwares obtained from the High
Energy Astrophysics Science Archive Research Center (HEASARC), provided
by NASA's Goddard Space Flight Center and Chandra X-ray Center (CXC).
NR 45
TC 17
Z9 17
U1 0
U2 1
PU IOP PUBLISHING LTD
PI BRISTOL
PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND
SN 2041-8205
EI 2041-8213
J9 ASTROPHYS J LETT
JI Astrophys. J. Lett.
PD APR 10
PY 2009
VL 695
IS 1
BP L4
EP L9
DI 10.1088/0004-637X/695/1/L4
PG 6
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 424BE
UT WOS:000264539700002
ER
PT J
AU Travnicek, PM
Hellinger, P
Schriver, D
Hercik, D
Slavin, JA
Anderson, BJ
AF Travnicek, Pavel M.
Hellinger, Petr
Schriver, David
Hercik, David
Slavin, James A.
Anderson, Brian J.
TI Kinetic instabilities in Mercury's magnetosphere: Three-dimensional
simulation results
SO GEOPHYSICAL RESEARCH LETTERS
LA English
DT Article
ID MESSENGERS 1ST FLYBY; MAGNETIC-FIELD
AB A self-consistent global three-dimensional kinetic study of Mercury's magnetosphere is carried out examining waves and instabilities generated by ion temperature anisotropy and plasma flow. The overall structure of Mercury's upstream bow shock and magnetosheath are qualitatively very similar to those of Earth. Beam-generated long-wavelength oscillations are present upstream of Mercury's quasi-parallel bow shock, whereas large-amplitude mirror waves develop downstream of the quasi-parallel bow shock in the magnetosheath. A train of mirror waves forms also downstream of the quasi-perpendicular bow shock. A velocity shear near the magnetopause can lead to formation of vortex-like structures. The magnetospheric cavity close to the planet's equatorial plane is filled with ions much hotter than the solar wind protons. A drift-driven plasma belt close to the equator is present in the model and contains plasma with high-temperature anisotropy, and the loss cone for charged particles in this region is large. The belt may cause diamagnetic effects superimposed on the planet's internal magnetic field and can interact with Mercury's magnetopause. Citation: Travnicek, P. M., P. Hellinger, D. Schriver, D. Hercik, J. A. Slavin, and B. J. Anderson (2009), Kinetic instabilities in Mercury's magnetosphere: Three-dimensional simulation results, Geophys. Res. Lett., 36, L07104, doi: 10.1029/2008GL036630.
C1 [Travnicek, Pavel M.; Hellinger, Petr; Hercik, David] Acad Sci Czech Republic, Inst Atmospher Phys, Prague 14131 4, Czech Republic.
[Slavin, James A.] NASA, Goddard Space Flight Ctr, Heliophys Sci Div, Greenbelt, MD 20771 USA.
[Travnicek, Pavel M.; Schriver, David] Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90095 USA.
[Anderson, Brian J.] Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA.
[Travnicek, Pavel M.; Hellinger, Petr] Acad Sci Czech Republic, Astron Inst, Prague 14131 4, Czech Republic.
RP Travnicek, PM (reprint author), Acad Sci Czech Republic, Inst Atmospher Phys, Bocni 2-1401, Prague 14131 4, Czech Republic.
EM trav@ig.cas.cz; petr.hellinger@ig.cas.cz; dave@igpp.ucla.edu;
james.a.slavin@nasa.gov; brian.j.anderson@jhuapl.edu
RI Anderson, Brian/I-8615-2012; Slavin, James/H-3170-2012; Hellinger,
Petr/F-5267-2014; Hercik, David/G-1224-2014; Travnicek,
Pavel/G-8608-2014
OI Slavin, James/0000-0002-9206-724X; Hellinger, Petr/0000-0002-5608-0834;
FU Academy of Sciences of the Czech Republic (ASCR) [300030805]; European
Space Agency [98068]; NASA MESSENGER Participating Scientist
[NNX07AR62G.]; Post Rouge, CNRS, France
FX Authors acknowledge the support of contract 300030805 from the Grant
Agency of the Academy of Sciences of the Czech Republic (ASCR), ESA PECS
contract 98068 from the European Space Agency, and NASA MESSENGER
Participating Scientist grant NNX07AR62G. This work has been performed
on the Amalka supercomputing facility, Institute of Atmospheric Physics,
ASCR. Part of this work has been supported by Post Rouge, CNRS, France,
awarded to PT.
NR 6
TC 24
Z9 24
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 APR 10
PY 2009
VL 36
AR L07104
DI 10.1029/2008GL036630
PG 5
WC Geosciences, Multidisciplinary
SC Geology
GA 431YT
UT WOS:000265101400001
ER
PT J
AU Tangborn, A
Stajner, I
Buchwitz, M
Khlystova, I
Pawson, S
Burrows, J
Hudman, R
Nedelec, P
AF Tangborn, Andrew
Stajner, Ivanka
Buchwitz, Michael
Khlystova, Iryna
Pawson, Steven
Burrows, John
Hudman, Rynda
Nedelec, Philippe
TI Assimilation of SCIAMACHY total column CO observations: Global and
regional analysis of data impact
SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
LA English
DT Article
ID CARBON-MONOXIDE; MODEL; EMISSIONS; SATELLITE; CHEMISTRY; MOPITT; SYSTEM
AB Carbon monoxide (CO) total column observations from the Scanning Imaging Absorption Spectrometer for Atmospheric Cartography (SCIAMACHY) on board Envisat-1 are assimilated into the Global Modeling and Assimilation Office constituent assimilation system for the period 1 April to 20 December 2004. The impact of the assimilation on CO distribution is evaluated using independent surface flask observations from the National Oceanic and Atmospheric Administration (NOAA)/ESRL global cooperative air sampling network and Measurement of Ozone and Water Vapor by Airbus In-Service Aircraft (MOZAIC) in situ CO profiles. Assimilation of SCIAMACHY data improves agreement of CO assimilation with both of these data sets on both global and regional scales compared to the free-running model. Regional comparisons with MOZAIC profiles made in western Europe, the northeastern United States, and the Arabian Peninsula show improvements at all three locations in the free troposphere and into the boundary layer over Arabia and the northeastern United States. Comparisons with NOAA Earth System Research Laboratory data improve at about two thirds of the surface observation sites. The systematic model errors related to the uncertainty of CO surface sources and the chemistry of CO losses are investigated through experiments with increased surface CO emissions over the Arabian Peninsula and/or globally reduced hydroxyl radical (OH) concentrations. Both model changes decrease mean CO errors at all altitudes in comparison to MOZAIC data over Dubai and Abu Dhabi. In contrast, errors in the assimilated CO are reduced by the increased emissions for pressures >= 800 hPa and by the reduced OH for pressures <= 600 hPa. Our analysis suggests that CO emissions over Dubai in 2004 are more than double those in the 1998 emissions inventory.
C1 [Tangborn, Andrew; Stajner, Ivanka; Pawson, Steven] NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Greenbelt, MD 20771 USA.
[Tangborn, Andrew] Univ Maryland Baltimore Cty, Joint Ctr Earth Syst Technol, Baltimore, MD 21228 USA.
[Buchwitz, Michael; Khlystova, Iryna; Burrows, John] Univ Bremen, Inst Environm Phys, D-28334 Bremen, Germany.
[Burrows, John] Ctr Ecol & Hydrol, Wallingford, Oxon, England.
[Hudman, Rynda] Harvard Univ, Atmospher Chem Modeling Grp, Cambridge, MA 02138 USA.
[Nedelec, Philippe] Univ Toulouse, CNRS, Lab Aerol, Observ Midi Pyrenees, F-31400 Toulouse, France.
RP Tangborn, A (reprint author), NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Code 610-1, Greenbelt, MD 20771 USA.
EM andrew.v.tangborn@nasa.gov; ivanka.stajner@noblis.org;
michael.buchwitz@iup.physik.uni-bremen.de;
iryna.khlystova@iup.physik.unibremen.de; steven.pawson@nasa.gov;
burrows@iup.physic.uni-bremen.de; hudman@berkeley.edu;
philippe.nedelec@aero.obs-mip.fr
RI Hudman, Rynda/C-6118-2009; Buchwitz, Michael/G-1510-2011; Stajner,
Ivanka/B-5228-2009; Pawson, Steven/I-1865-2014; Burrows,
John/B-6199-2014
OI Stajner, Ivanka/0000-0001-6103-3939; Pawson, Steven/0000-0003-0200-717X;
Burrows, John/0000-0002-6821-5580
FU GMAO [NASA NRA-03-OES-02]; NASA Modeling Analysis and Prediction (MAP)
grant
FX This project was funded in the GMAO under NASA NRA-03-OES-02 (carbon
cycle research) and a NASA Modeling Analysis and Prediction ( MAP)
grant. Computing resources were provided by NASA's High-End Computing
Program at GSFC. Funding for the University of Bremen came from DLR-Bonn
( grant 50EE0727), ESA ( PROMOTE), and the EU (AMFIC). The authors
acknowledge the strong support of the European Communities, Airbus, and
the airlines Lufthansa, Austrian, and Air France, who carry the MOZAIC
equipment free of charge and have performed maintenance since 1994. We
also gratefully acknowledge the contribution of Paul Novelli, who made
available the CO flask data from the NOAA/ESRL global cooperative air
sampling network. The comments from the three anonymous reviewers
greatly helped to improve the quality of the manuscript.
NR 31
TC 16
Z9 16
U1 0
U2 3
PU AMER GEOPHYSICAL UNION
PI WASHINGTON
PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA
SN 2169-897X
EI 2169-8996
J9 J GEOPHYS RES-ATMOS
JI J. Geophys. Res.-Atmos.
PD APR 10
PY 2009
VL 114
AR D07307
DI 10.1029/2008JD010781
PG 11
WC Meteorology & Atmospheric Sciences
SC Meteorology & Atmospheric Sciences
GA 431ZA
UT WOS:000265102100003
ER
PT J
AU Mostl, C
Farrugia, CJ
Miklenic, C
Temmer, M
Galvin, AB
Luhmann, JG
Kilpua, EKJ
Leitner, M
Nieves-Chinchilla, T
Veronig, A
Biernat, HK
AF Moestl, C.
Farrugia, C. J.
Miklenic, C.
Temmer, M.
Galvin, A. B.
Luhmann, J. G.
Kilpua, E. K. J.
Leitner, M.
Nieves-Chinchilla, T.
Veronig, A.
Biernat, H. K.
TI Multispacecraft recovery of a magnetic cloud and its origin from
magnetic reconnection on the Sun
SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
LA English
DT Article
ID CORONAL MASS EJECTIONS; FLUX ROPES; 2-RIBBON FLARE; CROSS-SECTION;
CLUSTER DATA; SOLAR-WIND; FIELD; MODEL; RECONSTRUCTION; MAGNETOPAUSE
AB Multipoint spacecraft observations of a magnetic cloud on 22 May 2007 have given us the opportunity to apply a multispacecraft technique to infer the structure of this large-scale magnetic flux rope in the solar wind. Combining WIND and STEREO-B magnetic field and plasma measurements, we construct a combined magnetic field map by integrating the Grad-Shafranov equation, this being one of the very first applications of this technique in the interplanetary context. From this we obtain robust results on the shape of the cross section, the orientation and magnetic fluxes of the cloud. The only slightly "flattened" shape is discussed with respect to its heliospheric environment and theoretical expectations. We also relate these results to observations of the solar source region and its associated two-ribbon flare on 19 May 2007, using Ha images from the Kanzelhohe observatory, SOHO/MDI magnetograms and SECCHI/EUVI 171 angstrom images. We find a close correspondence between the magnetic flux reconnected in the flare and the poloidal flux of the magnetic cloud. The axial flux of the cloud agrees with the prediction of a recent 3-D finite sheared arcade model to within a factor of 2, which is evidence for formation of at least half of the magnetic flux of the ejected flux rope during the eruption. We outline the relevance of this result to models of coronal mass ejection initiation, and find that to explain the solar and interplanetary observations elements from sheared arcade as well as erupting-flux-rope models are needed.
C1 [Moestl, C.; Miklenic, C.] Austrian Acad Sci, Space Res Inst, A-8042 Graz, Austria.
[Moestl, C.; Temmer, M.; Veronig, A.; Biernat, H. K.] Graz Univ, Inst Phys, A-8010 Graz, Austria.
[Farrugia, C. J.; Galvin, A. B.] Univ New Hampshire, Ctr Space Sci, Durham, NH 03824 USA.
[Farrugia, C. J.; Galvin, A. B.] Univ New Hampshire, Dept Phys, Durham, NH 03824 USA.
[Luhmann, J. G.; Kilpua, E. K. J.] Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA.
[Kilpua, E. K. J.] Univ Helsinki, Dept Phys, Div Theoret Phys, Helsinki, Finland.
[Leitner, M.] Univ Innsbruck, Inst Astro & Particle Phys, A-6020 Innsbruck, Austria.
[Nieves-Chinchilla, T.] NASA, Goddard Space Flight Ctr, Geospace Phys Lab, Greenbelt, MD 20771 USA.
RP Mostl, C (reprint author), Austrian Acad Sci, Space Res Inst, Schmiedlstr 6, A-8042 Graz, Austria.
EM moestlch@stud.uni-graz.at; charlie.farrugia@unh.edu
RI Kilpua, Emilia/G-8994-2012; Galvin, Antoinette/A-6114-2013; Veronig,
Astrid/B-8422-2009; Nieves-Chinchilla, Teresa/F-3482-2016;
OI Nieves-Chinchilla, Teresa/0000-0003-0565-4890; Moestl,
Christian/0000-0001-6868-4152; Temmer, Manuela/0000-0003-4867-7558
FU NASA WIND/SWE; MFI [NNG06GC75G, NNG06GD41G, NNX08AD11G]; University of
California, Berkeley [NAS5-03131]; Austrian Fonds zur Forderung der
wissenschaftlichen Forschung [P20145-N16, P20131-N16]
FX C. M. is supported by the young researchers fund of the Steiermarkische
Sparkasse. C.J.F. is a co-Investigator on STEREO/PLASTIC. This work is
supported by NASA WIND/SWE and MFI grants NNG06GC75G, NNG06GD41G and
NNX08AD11G. Work at the University of California, Berkeley, was
supported from STEREO grant NAS5-03131. It is also supported by the
Austrian Fonds zur Forderung der wissenschaftlichen Forschung under
projects P20145-N16 and P20131-N16. M. Temmer acknowledges project APART
11262 of the Austrian Academy of Sciences. We also acknowledge the use
of WIND data provided by the magnetometer and the solar wind experiment
teams at GSFC. This research was supported in part by an appointment to
the NASA Postdoctoral Program at Goddard Space Flight Center,
administered by Oak Ridge Associated Universities through a contract
with NASA.
NR 68
TC 27
Z9 27
U1 0
U2 2
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 APR 10
PY 2009
VL 114
AR A04102
DI 10.1029/2008JA013657
PG 19
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 432AD
UT WOS:000265105000002
ER
PT J
AU Ponchak, GE
Scardelletti, MC
Jordan, JL
AF Ponchak, G. E.
Scardelletti, M. C.
Jordan, J. L.
TI 270 degrees C, 1 GHz oscillator-type active antenna
SO ELECTRONICS LETTERS
LA English
DT Article
AB Reported is the first demonstration of an active antenna operating at 1 GHz and at temperatures above 200 degrees C. A Clapp oscillator integrated with a slot-ring antenna generated and transmitted a 1 GHz signal from 25 to 270 degrees C. The oscillation frequency varied by less than 4% over the temperature range.
RP Ponchak, GE (reprint author), NASA, Glenn Res Ctr, 21000 Brookpk Rd, Cleveland, OH 44135 USA.
EM george.ponchak@ieee.org
NR 7
TC 1
Z9 1
U1 0
U2 1
PU INST ENGINEERING TECHNOLOGY-IET
PI HERTFORD
PA MICHAEL FARADAY HOUSE SIX HILLS WAY STEVENAGE, HERTFORD SG1 2AY, ENGLAND
SN 0013-5194
J9 ELECTRON LETT
JI Electron. Lett.
PD APR 9
PY 2009
VL 45
IS 8
BP 386
EP U9
DI 10.1049/el.2009.0615
PG 2
WC Engineering, Electrical & Electronic
SC Engineering
GA 433VO
UT WOS:000265234100002
ER
PT J
AU Gautam, R
Hsu, NC
Lau, KM
Tsay, SC
Kafatos, M
AF Gautam, R.
Hsu, N. C.
Lau, K. -M.
Tsay, S. -C.
Kafatos, M.
TI Enhanced pre-monsoon warming over the Himalayan-Gangetic region from
1979 to 2007
SO GEOPHYSICAL RESEARCH LETTERS
LA English
DT Article
ID ASIAN SUMMER MONSOON; BLACK CARBON AEROSOLS; TIBETAN PLATEAU; CLIMATE;
EVOLUTION; IMPACTS; CLOUDS; TRENDS; RECORD
AB Fundamental to the onset of the Indian Summer Monsoon is the land-sea thermal gradient from the Indian Ocean to the Himalayas-Tibetan Plateau (HTP). The timing of the onset is strongly controlled by the meridional tropospheric temperature gradient due to the rapid pre-monsoon heating of the HTP compared to the relatively cooler Indian Ocean. Analysis of tropospheric temperatures from the longest available record of microwave satellite measurements reveals widespread warming over the Himalayan-Gangetic region and consequent strengthening of the land-sea thermal gradient. This trend is most pronounced in the pre-monsoon season, resulting in a warming of 2.7 degrees C in the 29-year record (1979-2007), when this region is strongly influenced by dust aerosols at elevated altitudes. The enhanced tropospheric warming is accompanied by increased atmospheric loading of absorbing aerosols, particularly vertically extended dust aerosols, raising the possibility that aerosol solar heating has amplified the seasonal warming and in turn strengthened the land-sea gradient. Citation: Gautam, R., N. C. Hsu, K.-M. Lau, S.-C. Tsay, and M. Kafatos (2009), Enhanced pre-monsoon warming over the Himalayan-Gangetic region from 1979 to 2007, Geophys. Res. Lett., 36, L07704, doi:10.1029/2009GL037641.
C1 [Gautam, R.] Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA.
[Gautam, R.; Hsu, N. C.; Lau, K. -M.; Tsay, S. -C.] NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA.
[Kafatos, M.] Chapman Univ, Schmid Coll Sci, Ctr Excellence Earth Observing, Orange, CA 92866 USA.
RP Gautam, R (reprint author), Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, 5523 Res Pk Dr,Suite 320, Baltimore, MD 21228 USA.
EM rgautam@umbc.edu
RI Gautam, Ritesh/E-9776-2010; Hsu, N. Christina/H-3420-2013; Tsay,
Si-Chee/J-1147-2014; Lau, William /E-1510-2012
OI Gautam, Ritesh/0000-0002-2177-9346; Lau, William /0000-0002-3587-3691
FU NASA EOS Program
FX This work is supported by grant from the NASA EOS Program, managed by
Hal Maring. We thank Colin Seftor for his help with the radiative
transfer model. We are grateful to the anonymous reviewers and the
associate Editor for providing constructive comments in improving an
earlier version of the manuscript.
NR 25
TC 91
Z9 92
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 APR 9
PY 2009
VL 36
AR L07704
DI 10.1029/2009GL037641
PG 5
WC Geosciences, Multidisciplinary
SC Geology
GA 431YS
UT WOS:000265101300003
ER
PT J
AU Devlin, MJ
Ade, PAR
Aretxaga, I
Bock, JJ
Chapin, EL
Griffin, M
Gundersen, JO
Halpern, M
Hargrave, PC
Hughes, DH
Klein, J
Marsden, G
Martin, PG
Mauskopf, P
Moncelsi, L
Netterfield, CB
Ngo, H
Olmi, L
Pascale, E
Patanchon, G
Rex, M
Scott, D
Semisch, C
Thomas, N
Truch, MDP
Tucker, C
Tucker, GS
Viero, MP
Wiebe, DV
AF Devlin, Mark J.
Ade, Peter A. R.
Aretxaga, Itziar
Bock, James J.
Chapin, Edward L.
Griffin, Matthew
Gundersen, Joshua O.
Halpern, Mark
Hargrave, Peter C.
Hughes, David H.
Klein, Jeff
Marsden, Gaelen
Martin, Peter G.
Mauskopf, Philip
Moncelsi, Lorenzo
Netterfield, Calvin B.
Ngo, Henry
Olmi, Luca
Pascale, Enzo
Patanchon, Guillaume
Rex, Marie
Scott, Douglas
Semisch, Christopher
Thomas, Nicholas
Truch, Matthew D. P.
Tucker, Carole
Tucker, Gregory S.
Viero, Marco P.
Wiebe, Donald V.
TI Over half of the far-infrared background light comes from galaxies at z
>= 1.2
SO NATURE
LA English
DT Article
ID DEGREE EXTRAGALACTIC SURVEY; DEEP SUBMILLIMETER SURVEY; FIELD-SOUTH
SURVEY; NUMBER COUNTS; SOURCE CATALOGS; STAR-FORMATION; HIGH-REDSHIFT;
LOCKMAN HOLE; SPITZER; CHANDRA
AB Submillimetre surveys during the past decade have discovered a population of luminous, high-redshift, dusty starburst galaxies(1-8). In the redshift range 1 <= z <= 4, these massive submillimetre galaxies go through a phase characterized by optically obscured star formation at rates several hundred times that in the local Universe. Half of the starlight from this highly energetic process is absorbed and thermally re-radiated by clouds of dust at temperatures near 30 K with spectral energy distributions peaking at 100 mu m in the rest frame(9). At 1 <= z <= 4, the peak is redshifted to wavelengths between 200 and 500 mu m. The cumulative effect of these galaxies is to yield extragalactic optical and far-infrared backgrounds with approximately equal energy densities. Since the initial detection of the far-infrared background (FIRB)(10), higher-resolution experiments have sought to decompose this integrated radiation into the contributions from individual galaxies. Here we report the results of an extragalactic survey at 250, 350 and 500 mu m. Combining our results at 500 mu m with those at 24 mu m, we determine that all of the FIRB comes from individual galaxies, with galaxies at z >= 1.2 accounting for 70% of it. As expected, at the longest wavelengths the signal is dominated by ultraluminous galaxies at z > 1.
C1 [Devlin, Mark J.; Klein, Jeff; Rex, Marie; Semisch, Christopher; Truch, Matthew D. P.] Univ Penn, Dept Phys & Astron, Philadelphia, PA 19104 USA.
[Ade, Peter A. R.; Griffin, Matthew; Hargrave, Peter C.; Mauskopf, Philip; Moncelsi, Lorenzo; Pascale, Enzo; Tucker, Carole] Cardiff Univ, Sch Phys & Astron, Cardiff CF24 3AA, S Glam, Wales.
[Aretxaga, Itziar; Hughes, David H.] Inst Nacl Astrofis Opt & Electr, Puebla, Mexico.
[Bock, James J.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
[Chapin, Edward L.; Halpern, Mark; Marsden, Gaelen; Ngo, Henry; Scott, Douglas] Univ British Columbia, Dept Phys & Astron, Vancouver, BC V6T 1Z1, Canada.
[Gundersen, Joshua O.; Thomas, Nicholas] Univ Miami, Dept Phys, Coral Gables, FL 33146 USA.
[Martin, Peter G.] Univ Toronto, Canadian Inst Theoret Astrophys, Toronto, ON M5S 3H8, Canada.
[Martin, Peter G.; Netterfield, Calvin B.; Viero, Marco P.] Univ Toronto, Dept Astron & Astrophys, Toronto, ON M5S 3H4, Canada.
[Netterfield, Calvin B.; Wiebe, Donald V.] Univ Toronto, Dept Phys, Toronto, ON M5S 1A7, Canada.
[Olmi, Luca] Univ Puerto Rico, Dept Phys, Rio Piedras, PR 00931 USA.
[Olmi, Luca] INAF Osservatorio Astrofis Arcetri, I-50125 Florence, Italy.
[Patanchon, Guillaume] Univ Paris Diderot, Lab APC, F-75205 Paris, France.
[Tucker, Gregory S.] Brown Univ, Dept Phys, Providence, RI 02912 USA.
RP Devlin, MJ (reprint author), Univ Penn, Dept Phys & Astron, 209 S 33rd St, Philadelphia, PA 19104 USA.
EM devlin@physics.upenn.edu
RI Klein, Jeffrey/E-3295-2013;
OI Scott, Douglas/0000-0002-6878-9840; Olmi, Luca/0000-0002-1162-7947; Ngo,
Henry/0000-0001-5172-4859
FU NASAUS National Science Foundation Office; Canadian Space Agency;
Natural Sciences and Engineering Research Council of Canada; UK Science
and Technology Facilities Council
FX We acknowledge the support of NASA, the US National Science Foundation
Office of Polar Programs, the Canadian Space Agency, the Natural
Sciences and Engineering Research Council of Canada and the UK Science
and Technology Facilities Council. We are grateful to B. Magnelli for
help with the FIDEL 24-mu m data. This research was enabled by the
WestGrid computing resources and the SIMBAD and NASA/IPAC databases. We
thank the Columbia Scientific Balloon Facility, Ken Borek Air Ltd and
the mountaineers of McMurdo Station for their work.
NR 28
TC 136
Z9 136
U1 0
U2 5
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 APR 9
PY 2009
VL 458
IS 7239
BP 737
EP 739
DI 10.1038/nature07918
PG 3
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA 433GZ
UT WOS:000265193600034
PM 19360081
ER
PT J
AU Konhauser, KO
Pecoits, E
Lalonde, SV
Papineau, D
Nisbet, EG
Barley, ME
Arndt, NT
Zahnle, K
Kamber, BS
AF Konhauser, Kurt O.
Pecoits, Ernesto
Lalonde, Stefan V.
Papineau, Dominic
Nisbet, Euan G.
Barley, Mark E.
Arndt, Nicholas T.
Zahnle, Kevin
Kamber, Balz S.
TI Oceanic nickel depletion and a methanogen famine before the Great
Oxidation Event
SO NATURE
LA English
DT Article
ID ATMOSPHERIC OXYGEN; METHANOBACTERIUM-THERMOAUTOTROPHICUM; RISE; NI;
GEOCHEMISTRY; TECTONICS; CHEMISTRY; SULFUR; MANTLE; GROWTH
AB It has been suggested that a decrease in atmospheric methane levels triggered the progressive rise of atmospheric oxygen, the so-called Great Oxidation Event, about 2.4 Gyr ago(1). Oxidative weathering of terrestrial sulphides, increased oceanic sulphate, and the ecological success of sulphate-reducing microorganisms over methanogens has been proposed as a possible cause for the methane collapse(1), but this explanation is difficult to reconcile with the rock record(2,3). Banded iron formations preserve a history of Precambrian oceanic elemental abundance and can provide insights into our understanding of early microbial life and its influence on the evolution of the Earth system(4,5). Here we report a decline in the molar nickel to iron ratio recorded in banded iron formations about 2.7 Gyr ago, which we attribute to a reduced flux of nickel to the oceans, a consequence of cooling upper-mantle temperatures and decreased eruption of nickel-rich ultramafic rocks at the time. We measured nickel partition coefficients between simulated Precambrian sea water and diverse iron hydroxides, and subsequently determined that dissolved nickel concentrations may have reached similar to 400nM throughout much of the Archaean eon, but dropped below similar to 200nM by 2.5 Gyr ago and to modern day values(6) (similar to 9 nM) by similar to 550 Myr ago. Nickel is a key metal cofactor in several enzymes of methanogens(7) and we propose that its decline would have stifled their activity in the ancient oceans and disrupted the supply of biogenic methane. A decline in biogenic methane production therefore could have occurred before increasing environmental oxygenation and not necessarily be related to it. The enzymatic reliance of methanogens on a diminishing supply of volcanic nickel links mantle evolution to the redox state of the atmosphere.
C1 [Konhauser, Kurt O.; Pecoits, Ernesto; Lalonde, Stefan V.] Univ Alberta, Dept Earth & Atmospher Sci, Edmonton, AB T6G 2E3, Canada.
[Papineau, Dominic] Carnegie Inst Sci, Geophys Lab, Washington, DC 20015 USA.
[Nisbet, Euan G.] Royal Holloway Univ London, Dept Earth Sci, Egham TW20 0EX, Surrey, England.
[Barley, Mark E.] Univ Western Australia, Sch Earth & Environm, Crawley, WA 6009, Australia.
[Arndt, Nicholas T.] Univ Grenoble 1, Lab Geodynam Chaine Alpines Maison Geosci, F-38041 Grenoble, France.
[Zahnle, Kevin] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA.
[Kamber, Balz S.] Laurentian Univ, Dept Earth Sci, Sudbury, ON P3E 2C6, Canada.
RP Konhauser, KO (reprint author), Univ Alberta, Dept Earth & Atmospher Sci, Edmonton, AB T6G 2E3, Canada.
EM kurtk@ualberta.ca
RI Kamber, Balz/A-1823-2008; Lalonde, Stefan/I-8879-2014;
OI Kamber, Balz/0000-0002-8720-0608; Lalonde, Stefan/0000-0003-1318-2280;
Konhauser, Kurt/0000-0001-7722-7068
FU Natural Science and Engineering Research Council of Canada (NSERC);
Australian Research Council (ARC)
FX We thank M. Labbe for sample preparation, G. Chen and A. Simonetti for
assistance with LA-ICP-MS analyses in the Radiogenic Isotope Facility at
the University of Alberta, and S. Matveev for assistance with electron
microprobe analyses. Field assistance by W. Mueller is acknowledged for
Hunter Mine Group samples. Samples from the Loch Maree Group were
provided by A. Wright. Funding was provided by the Natural Science and
Engineering Research Council of Canada (NSERC) to K. O. K., the Canada
Research Chairs Program to B. S. K., the Australian Research Council
(ARC) to M. E. B., and NASA Exobiology and Evolutionary Biology Program
individually to D. P. and K. Z. This manuscript was improved by
discussions with R. Buick, J. Kasting and M. Lesher, and reviews by R.
Frei and M. Saito.
NR 40
TC 165
Z9 177
U1 9
U2 106
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 APR 9
PY 2009
VL 458
IS 7239
BP 750
EP U85
DI 10.1038/nature07858
PG 5
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA 433GZ
UT WOS:000265193600038
PM 19360085
ER
PT J
AU Lovell, CS
Wise, KE
Kim, JW
Lillehei, PT
Harrison, JS
Park, C
AF Lovell, Conrad S.
Wise, Kristopher E.
Kim, Jae-Woo
Lillehei, Peter T.
Harrison, Joycelyn S.
Park, Cheol
TI Thermodynamic approach to enhanced dispersion and physical properties in
a carbon nanotube/polypeptide nanocomposite
SO POLYMER
LA English
DT Article
DE Copolypeptide; Single wall carbon nanotube (SWCNT); Nanotube/polymer
interactions
ID DESIGNED AMPHIPHILIC PEPTIDE; NANOTUBE-POLYMER COMPOSITES;
MECHANICAL-PROPERTIES; INFRARED SPECTRA; FUNCTIONALIZATION;
POLYPEPTIDES; STIFFNESS; BLENDS; PHASE
AB A high molecular weight synthetic polypeptide has been designed which exhibits favorable interactions with single wall carbon nanotubes (SWCNTs). The enthalpic and entropic penalties of mixing between these two molecules are reduced due to the polypeptide's aromatic sidechains and helical secondary structure, respectively. These enhanced interactions result in a well dispersed SWCNT/Poly (L-Leucineran-L-Phenylalanine) nanocomposite with enhanced mechanical and electrical properties using only shear mixing and sonication. At 0.5 wt% loading of SWCNT filler, the nanocomposite exhibits simultaneous increases in the Young's modulus, failure strain, and toughness of 8%, 120%, and 144%, respectively. At 1 kHz, the same nanotube loading level also enhances the dielectric constant from 2.95 to 22.81, while increasing the conductivity by four orders of magnitude. (c) 2009 Elsevier Ltd. All rights reserved.
C1 [Lovell, Conrad S.; Wise, Kristopher E.; Kim, Jae-Woo; Park, Cheol] Natl Inst Aerosp, Hampton, VA 23666 USA.
[Lovell, Conrad S.] Univ Virginia, Dept Mat Sci & Engn, Charlottesville, VA 22904 USA.
[Wise, Kristopher E.; Lillehei, Peter T.; Harrison, Joycelyn S.] NASA, Langley Res Ctr, Adv Mat & Proc Branch, Hampton, VA 23681 USA.
[Park, Cheol] Univ Virginia, Dept Mech & Aerosp Engn, Charlottesville, VA 22904 USA.
RP Park, C (reprint author), Natl Inst Aerosp, 100 Explorat Way, Hampton, VA 23666 USA.
EM cheol.park-1@nasa.gov
RI Kim, Jae-Woo/A-8314-2008; Lillehei, Peter/C-9196-2009
OI Lillehei, Peter/0000-0001-8183-9980
FU NASA University Research, Engineering and Technology Institute on Bio
Inspired Materials (BIMat) [NCC-1-02037]
FX The authors thank Nancy M. Holloway for electroding the samples. They
also acknowledge Timothy Deming, Galen Stucky and Edward Worthington for
supplying the LFcopolypepticle. Lovell appreciates the guidance and
discussion of Dr. James M. Fitz-Gerald at the University of Virginia.
Park and Wise appreciate NASA University Research, Engineering and
Technology Institute on Bio Inspired Materials (BIMat) under Award No.
NCC-1-02037 for support in part.
NR 53
TC 11
Z9 13
U1 0
U2 18
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 APR 9
PY 2009
VL 50
IS 8
BP 1925
EP 1932
DI 10.1016/j.polymer.2009.02.016
PG 8
WC Polymer Science
SC Polymer Science
GA 431ER
UT WOS:000265044600015
ER
PT J
AU Collilieux, X
Altamimi, Z
Ray, J
van Dam, T
Wu, X
AF Collilieux, X.
Altamimi, Z.
Ray, J.
van Dam, T.
Wu, X.
TI Effect of the satellite laser ranging network distribution on geocenter
motion estimation
SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
LA English
DT Article
ID TERRESTRIAL REFERENCE FRAME; SURFACE MASS VARIATIONS; LOADING DATA;
ENERGY BALANCES; TIME-SERIES; LAND WATER; EARTH; DEFORMATION; DORIS;
DEFINITION
AB SLR network translations estimated between a quasi-instantaneous station position set, theoretically expressed with respect to the center of mass of the Earth ( CM), and a secular reference frame are the signature of the motion of the CM with respect to the Earth crust. Geocenter motion is defined here to be the motion of the CM with respect to the geometric center of the solid Earth surface (CF). SLR translational variations cannot be rigorously interpreted as identical to geocenter motion due to the sparse and nonuniform distribution of the SLR network. Their difference is called the network effect, which should be dominated at subdecadal timescales by loading signals. We have computed translation time series of the SLR network using two independent geophysically based loading models. One is a displacement model estimated from surface fluid data ( Green's function approach), called forward model, and the other is a displacement model estimated from GPS and ocean bottom pressure (OBP) data, called inverse model. The translation models have been subtracted from their respective geocenter motion models computed from degree-1 mass load coefficients in order to evaluate their network effect biases. Scatter due to the SLR network effect is at the level of 1.5 mm RMS. It could slightly shift the phase of the annual SLR geocenter motion estimate by less than 1 month and could affect X and Z annual geocenter motion amplitudes at the 1-mm level, which is about one third of the expected signal. Two distinct methods are suggested to account for network effect when comparing SLR translations to geocenter motion models. The first is to add the network effect term predicted by a displacement model to the geocenter motion loading model. The second relies on an adequate combination of SLR and GPS products to estimate SLR translation that could be better compared with geocenter motion.
C1 [Collilieux, X.; Altamimi, Z.] Inst Geog Natl, Lab Rech Geodesie, F-77455 Marne La Vallee 2, France.
[Ray, J.] NOAA, Natl Geodet Survey, Silver Spring, MD 20910 USA.
[van Dam, T.] Univ Luxembourg, Dept Phys & Mat Sci, L-1511 Luxembourg, Luxembourg.
[Wu, X.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
RP Collilieux, X (reprint author), Inst Geog Natl, Lab Rech Geodesie, 6-8 Ave Blaise Pascal, F-77455 Marne La Vallee 2, France.
EM xavier.collilieux@ign.fr; tonie.vandam@uni.lu; Xiaoping.Wu@jpl.nasa.gov
RI Altamimi, Zuheir/A-4168-2009
NR 48
TC 31
Z9 33
U1 1
U2 14
PU AMER GEOPHYSICAL UNION
PI WASHINGTON
PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA
SN 2169-9313
EI 2169-9356
J9 J GEOPHYS RES-SOL EA
JI J. Geophys. Res.-Solid Earth
PD APR 7
PY 2009
VL 114
AR B04402
DI 10.1029/2008JB005727
PG 17
WC Geochemistry & Geophysics
SC Geochemistry & Geophysics
GA 431ZQ
UT WOS:000265103700001
ER
PT J
AU Sangalli, L
Knudsen, DJ
Larsen, MF
Zhan, T
Pfaff, RF
Rowland, D
AF Sangalli, L.
Knudsen, D. J.
Larsen, M. F.
Zhan, T.
Pfaff, R. F.
Rowland, D.
TI Rocket-based measurements of ion velocity, neutral wind, and electric
field in the collisional transition region of the auroral ionosphere
SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
LA English
DT Article
ID FREQUENCY; TEMPERATURES; ANALYZER; EISCAT; RADAR
AB The JOULE-II sounding rocket salvo was launched from Poker Flat Rocket Range into weak pulsating aurora following a moderate substorm at 0345 LT on 19 January 2007. We present in situ measurements of ion flow velocity and electric and magnetic fields combined with neutral wind observations derived from ground observations of in situ chemical tracers. Measured ion drifts in the 150-198 km and 92-105 km altitude ranges are consistent with (E) over right arrow X (B) over right arrow motion to within 16 m s(-1) rms and with neutral wind velocity to within 20 m s(-1), respectively. From these measurements we have calculated the ratio kappa of the ion cyclotron and ion collision frequencies, finding kappa = 1 at an altitude of 118 +/- 0.3 km. Using direct measurements of ion current, we calculate the Joule heating rate and Pedersen and Hall conductivity profiles for this moderately active event and find height-integrated values of 390 W km(-2) and 0.59 and 2.22 S, respectively. We also find that these values would have errors of up to tens of percent without coincident neutral wind measurements, and presumably more so during more active conditions. Ion flow vectors were measured at a rate of 125 s(-1); however, no significant fluctuations were observed at spatial/temporal scales below similar to 350 m and 0.5 s. Observational limits were 5.5 m and 0.016 s.
C1 [Sangalli, L.; Knudsen, D. J.] Univ Calgary, Dept Phys & Astron, Calgary, AB T2N 1N4, Canada.
[Larsen, M. F.; Zhan, T.] Clemson Univ, Dept Phys & Astron, Clemson, SC 29634 USA.
[Pfaff, R. F.; Rowland, D.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
RP Sangalli, L (reprint author), Univ Calgary, Dept Phys & Astron, 2500 Univ Dr NW, Calgary, AB T2N 1N4, Canada.
EM sangalli@phys.ucalgary.ca; knudsen@phys.ucalgary.ca;
mlarsen@clemson.edu; Robert.F.Pfaff@nasa.gov; Douglas.E.Rowland@nasa.gov
RI Rowland, Douglas/F-5589-2012; Larsen, Miguel/A-1079-2013; Pfaff,
Robert/F-5703-2012
OI Rowland, Douglas/0000-0003-0948-6257; Pfaff, Robert/0000-0002-4881-9715
NR 17
TC 17
Z9 17
U1 1
U2 4
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 APR 7
PY 2009
VL 114
AR A04306
DI 10.1029/2008JA013757
PG 10
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 432AA
UT WOS:000265104700001
ER
PT J
AU Glavin, DP
Dworkin, JP
AF Glavin, Daniel P.
Dworkin, Jason P.
TI Enrichment of the amino acid L-isovaline by aqueous alteration on CI and
CM meteorite parent bodies
SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF
AMERICA
LA English
DT Article
DE enantiomeric excess; homochirality; origin of life; carbonaceous
chondrite
ID STAR-FORMATION REGIONS; MURCHISON METEORITE; CARBONACEOUS CHONDRITES;
ASYMMETRIC AUTOCATALYSIS; CIRCULAR-POLARIZATION; ORGANIC-COMPOUNDS;
HOMOCHIRALITY; ORIGIN; AMPLIFICATION; MINERALOGY
AB The distribution and enantiomeric composition of the 5-carbon (C(5)) amino acids found in CI-, CM-, and CR-type carbonaceous meteorites were investigated by using liquid chromatography fluorescence detection/TOF-MS coupled with o-phthaldialdehyde/N-acetyl- L-cysteine derivatization. A large L-enantiomeric excess (ee) of the alpha-methyl amino acid isovaline was found in the CM meteorite Murchison (L(ee) = 18.5 +/- 2.6%) and the CI meteorite Orgueil (L(ee) = 15.2 +/- 4.0%). The measured value for Murchison is the largest enantiomeric excess in any meteorite reported to date, and the Orgueil measurement of an isovaline excess has not been reported previously for this or any CI meteorite. The L-isovaline enrichments in these two carbonaceous meteorites cannot be the result of interference from other C(5) amino acid isomers present in the samples, analytical biases, or terrestrial amino acid contamination. We observed no L-isovaline enrichment for the most primitive unaltered Antarctic CR meteorites EET 92042 and QUE 99177. These results are inconsistent with UV circularly polarized light as the primary mechanism for L-isovaline enrichment and indicate that amplification of a small initial isovaline asymmetry in Murchison and Orgueil occurred during an extended aqueous alteration phase on the meteorite parent bodies. The large asymmetry in isovaline and other alpha-dialkyl amino acids found in altered CI and CM meteorites suggests that amino acids delivered by asteroids, comets, and their fragments would have biased the Earth's prebiotic organic inventory with left-handed molecules before the origin of life.
C1 [Glavin, Daniel P.; Dworkin, Jason P.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
RP Glavin, DP (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
EM daniel.p.glavin@nasa.gov
RI Glavin, Daniel/D-6194-2012; Dworkin, Jason/C-9417-2012
OI Glavin, Daniel/0000-0001-7779-7765; Dworkin, Jason/0000-0002-3961-8997
FU National Aeronautics and Space Administration Astrobiology Institute;
National Aeronautics and Space Administration Cosmo-chemistry;
Astrobiology: Exobiology and Evolutionary Biology programs
FX We thank K. Righter, T. McCoy, L. Welzenbach, and P. Ehrenfreund for
providing the meteorite samples used in this study; S. Pizzarello, S.
Miller, S. Davies, R. Duke, and R. Hudson for several amino acid
standards; A. Lewis for optimizing the LC analytical separation
conditions; M. Martin for help optimizing the QqQ-MS conditions; C.
Alexander and L. Chizmadia for helpful discussions; O. Botta for
assistance with the meteorite extractions; and A. Schwartz and an
anonymous reviewer for helpful comments. Funding support was received
from the National Aeronautics and Space Administration Astrobiology
Institute and the National Aeronautics and Space Administration
Cosmo-chemistry and Astrobiology: Exobiology and Evolutionary Biology
programs.
NR 54
TC 133
Z9 137
U1 2
U2 39
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 APR 7
PY 2009
VL 106
IS 14
BP 5487
EP 5492
DI 10.1073/pnas.0811618106
PG 6
WC Multidisciplinary Sciences
SC Science & Technology - Other Topics
GA 430CX
UT WOS:000264967500008
PM 19289826
ER
PT J
AU Hudman, RC
Murray, LT
Jacob, DJ
Turquety, S
Wu, S
Millet, DB
Avery, M
Goldstein, AH
Holloway, J
AF Hudman, R. C.
Murray, L. T.
Jacob, D. J.
Turquety, S.
Wu, S.
Millet, D. B.
Avery, M.
Goldstein, A. H.
Holloway, J.
TI North American influence on tropospheric ozone and the effects of recent
emission reductions: Constraints from ICARTT observations
SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
LA English
DT Article
ID CARBON-MONOXIDE; SURFACE OZONE; POLLUTION; ATLANTIC; METEOROLOGY; MODEL
AB We use observations from the International Consortium for Atmospheric Research on Transport and Transformation (ICARTT) campaign over eastern North America in summer 2004, interpreted with a global 3-D model of tropospheric chemistry (GEOS-Chem), to improve and update estimates of North American influence on global tropospheric ozone and the effect of recent U. S. anthropogenic reductions on surface ozone pollution. We find that the 50% decrease in U. S. stationary NOx sources since 1999 has decreased mean U. S. boundary layer ozone concentrations by 6-8 ppbv in the southeast and 4-6 ppbv in the Midwest. The observed dO(3)/dCO molar enhancement ratio in the U. S. boundary layer during ICARTT was 0.46 mol mol(-1), larger than the range of 0.3-0.4 from studies in the early 1990s, possibly reflecting the decrease in the NOx/CO emission ratio as well as an increase in the ozone production efficiency per unit NOx. North American NOx emissions during summer 2004 as constrained by the ICARTT observations (0.72 Tg N fossil fuel, 0.11 Tg N biomass burning, 0.28 Tg N lightning for 1 July to 15 August) enhanced the hemispheric tropospheric ozone burden by 12.4%, with comparable contributions from fossil fuel and lightning (5-6%), but only 1% from biomass burning emissions despite 2004 being a record fire year over Alaska and western Canada.
C1 [Avery, M.] NASA, Langley Res Ctr, Div Atmospher Sci, Hampton, VA 23681 USA.
[Goldstein, A. H.] Univ Calif Berkeley, Dept Environm Sci Policy & Management, Berkeley, CA 94720 USA.
[Holloway, J.] NOAA, Earth Syst Res Lab, Boulder, CO 80305 USA.
[Hudman, R. C.; Murray, L. T.; Jacob, D. J.; Turquety, S.; Wu, S.; Millet, D. B.] Harvard Univ, Sch Engn & Appl Sci, Cambridge, MA 02138 USA.
[Hudman, R. C.; Murray, L. T.; Jacob, D. J.; Turquety, S.; Wu, S.; Millet, D. B.] Harvard Univ, Dept Earth & Planetary Sci, Cambridge, MA 02138 USA.
[Holloway, J.] Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA.
RP Hudman, RC (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA.
EM hudman@berkeley.edu
RI Hudman, Rynda/C-6118-2009; Goldstein, Allen/A-6857-2011; Millet,
Dylan/G-5832-2012; Holloway, John/F-9911-2012; Murray, Lee/F-2296-2014;
Chem, GEOS/C-5595-2014
OI Goldstein, Allen/0000-0003-4014-4896; Holloway,
John/0000-0002-4585-9594; Murray, Lee/0000-0002-3447-3952;
FU NASA Global Tropospheric Chemistry Program; NOAA Office of Global
Programs
FX This work was funded by the NASA Global Tropospheric Chemistry Program
and by the NOAA Office of Global Programs. Aboard the NOAA WP-3D
aircraft measurements were provided for ozone, NO, NO2 (Tom
Ryerson, NOAA ESRL), acetonitrile (Joost De Gouw, CIRES/NOAA ESRL), HNO3
(Andy Neuman, NOAA CIRES/ESRL), and PAN (Frank Flocke and Aaron Swanson,
NCAR) and aboard the NASA DC-8 aircraft for HCN and PAN (Hanwant Singh,
NASA Ames), NO2 (Ron Cohen and Tim Bertram, University of
California, Berkeley), and NO (Bill Brune and Xinrong Ren).
NR 49
TC 31
Z9 31
U1 1
U2 24
PU AMER GEOPHYSICAL UNION
PI WASHINGTON
PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA
SN 2169-897X
EI 2169-8996
J9 J GEOPHYS RES-ATMOS
JI J. Geophys. Res.-Atmos.
PD APR 4
PY 2009
VL 114
AR D07302
DI 10.1029/2008JD010126
PG 9
WC Meteorology & Atmospheric Sciences
SC Meteorology & Atmospheric Sciences
GA 428QE
UT WOS:000264863100001
ER
PT J
AU Yue, GK
Fromm, MD
Shettle, EP
AF Yue, Glenn K.
Fromm, Michael D.
Shettle, Eric P.
TI Intercomparison of aerosol extinction measured by Stratospheric Aerosol
and Gas Experiment (SAGE) II and III
SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
LA English
DT Article
ID POAM-III; SATELLITE EXPERIMENTS; INTEGRAL PROPERTIES; SAM-II; SIMULATED
EXTINCTION; SIZE DISTRIBUTIONS; POLAR OZONE; VALIDATION; INSTRUMENT;
RETRIEVAL
AB Stratospheric Aerosol and Gas Experiment (SAGE) II and SAGE III are two satellite experiments designed to monitor aerosol extinction and the concentration of trace gases in the atmosphere using the solar and/or lunar occultation technique. While SAGE III used nine aerosol channels, four of them were centered at wavelengths very close or equal to the four aerosol channels used by SAGE II. Since both satellites conducted measurements between 2002 and 2005, there are comparison opportunities when their measurement locations on the same day are nearly coincident. In this study, the coincidence events are identified, and the aerosol extinction coefficients, color ratios (ratio of the extinction at two wavelengths), and optical depths measured by both satellites are compared. It is found that in the main stratospheric aerosol layer, between about 18 and 26 km, the differences of extinction coefficients are generally within their measurement uncertainties and are less than about 30%. The discrepancy between the wavelength dependence of the aerosol extinction coefficient, color ratio, and optical depth measured by SAGE II and SAGE III is also discussed. In the main stratospheric aerosol layer, the SAGE III mode radius deduced from the color ratio is about 20 to 30% less than the SAGE II mode radius. Wavelength dependence biases of the aerosol extinction coefficient evident in prior releases of SAGE III data persist in version 4.00.
C1 [Yue, Glenn K.] NASA, Langley Res Ctr, Hampton, VA 23681 USA.
[Fromm, Michael D.; Shettle, Eric P.] USN, Res Lab, Washington, DC 20375 USA.
RP Yue, GK (reprint author), NASA, Langley Res Ctr, MS 475,100 NASA Rd, Hampton, VA 23681 USA.
EM glenn.k.yue@nasa.gov
RI Fromm, Michael/F-4639-2010
FU NASA Office of Earth Science; NRL internal funding (from the Office of
Naval Research)
FX M. D. F. and E. P. S. were supported in part by a grant from the NASA
Office of Earth Science and in part by NRL internal funding (from the
Office of Naval Research).
NR 25
TC 1
Z9 1
U1 0
U2 1
PU AMER GEOPHYSICAL UNION
PI WASHINGTON
PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA
SN 2169-897X
EI 2169-8996
J9 J GEOPHYS RES-ATMOS
JI J. Geophys. Res.-Atmos.
PD APR 4
PY 2009
VL 114
AR D07205
DI 10.1029/2008JD010452
PG 10
WC Meteorology & Atmospheric Sciences
SC Meteorology & Atmospheric Sciences
GA 428QE
UT WOS:000264863100002
ER
PT J
AU Clilverd, MA
Seppala, A
Rodger, CJ
Mlynczak, MG
Kozyra, JU
AF Clilverd, Mark A.
Seppala, Annika
Rodger, Craig J.
Mlynczak, Martin G.
Kozyra, Janet U.
TI Additional stratospheric NOx production by relativistic electron
precipitation during the 2004 spring NOx descent event
SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
LA English
DT Article
ID ODD NITROGEN; MIDDLE ATMOSPHERE; MODEL; THERMOSPHERE; CHEMISTRY
AB We analyze in detail the February 2004 Global Ozone Monitoring by Occultation of Stars (GOMOS) NO2 observations in the northern polar latitudes during the springtime descent of NOx from the mesosphere into the stratosphere. We combine GOMOS observations with SABER-observed NO 5.3 mu m radiated power and an AARDDVARK-derived radio wave index (RWI) to describe the impact of the 11 February geomagnetic storm. Energetic electron precipitation generated some additional NOx, supplementing the original amounts that were already descending. At altitudes of 50-70 km, GOMOS observations of NO2 showed a delayed response to the geomagnetic storm, with NO2 being generated 3 days after the start of the storm. The delayed response and duration of NO2 production was found to be consistent with the increase in the flux of relativistic electrons measured by GOES at geostationary orbit and by POES through relativistic electron contamination of the >16 MeV proton channel. Using the Sodankyla Ion and Neutral Chemistry model (SIC), we found that a good fit to the observed NO2 mixing ratios at the peak of the geomagnetic storm effect was produced by a monoenergetic 1.25 MeV electron beam with a flux of similar to 0.3 x10(6) el cm(-2) sr(-1) s(-1) keV(-1) or with a "hard'' electron spectra taken from Gaines et al. (1995) but with fluxes enhanced by a factor of 15, i.e., 8 x 10(4) el cm(-2) sr(-1) s(-1) for 2-6 MeV. Prior to the storm the descending NO2 had average mixing ratio values of similar to 150 ppbv. The geomagnetic storm-induced relativistic electron precipitation event doubled the amount of NOx descending into the stratosphere to similar to 300 ppbv after the storm.
C1 [Clilverd, Mark A.] British Antarctic Survey, NERC, Div Phys Sci, Cambridge CB3 0ET, England.
[Kozyra, Janet U.] Univ Michigan, Dept Atmospher Ocean & Space Sci, Coll Engn, Ann Arbor, MI 48109 USA.
[Mlynczak, Martin G.] NASA, Langley Res Ctr, Hampton, VA 23681 USA.
[Rodger, Craig J.] Univ Otago, Dept Phys, Dunedin, New Zealand.
[Seppala, Annika] Finnish Meteorol Inst, FIN-00101 Helsinki, Finland.
RP Clilverd, MA (reprint author), British Antarctic Survey, NERC, Div Phys Sci, High Cross,Madingley Rd, Cambridge CB3 0ET, England.
EM macl@bas.ac.uk; annika.seppala@fmi.fi; crodger@physics.otago.ac.nz;
martin.g.mlynczak@nasa.gov; jukozyra@umich.edu
RI Mlynczak, Martin/K-3396-2012; Seppala, Annika/C-8031-2014; Rodger,
Craig/A-1501-2011
OI Seppala, Annika/0000-0002-5028-8220; Rodger, Craig/0000-0002-6770-2707
FU Academy of Finland
FX M. A. C. would like to thank Glenda Harden at BAS for her valuable
support in the development of this work. A. S. thanks the Academy of
Finland for their support though the EPPIC project. The authors would
like to thank the SABER and GOMOS science teams for useful and
informative discussions regarding this work. We are grateful to NASA and
the National Oceanic and Atmospheric Administration (NOAA) for the
observations provided by the Polar Operational Environmental Satellite
(POES) and Geostationary Operational Environmental Satellite Program
(GOES) programs.
NR 43
TC 16
Z9 16
U1 0
U2 5
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 APR 3
PY 2009
VL 114
AR A04305
DI 10.1029/2008JA013472
PG 11
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 428RE
UT WOS:000264866100001
ER
PT J
AU Rath, C
Morfill, GE
Rossmanith, G
Banday, AJ
Gorski, KM
AF Raeth, C.
Morfill, G. E.
Rossmanith, G.
Banday, A. J.
Gorski, K. M.
TI Model-Independent Test for Scale-Dependent Non-Gaussianities in the
Cosmic Microwave Background
SO PHYSICAL REVIEW LETTERS
LA English
DT Article
ID PROBE SKY MAPS; ANISOTROPY-PROBE; INFLATIONARY UNIVERSE; K-INFLATION;
WMAP DATA; PERTURBATIONS; SIGNATURES; FLATNESS; ISOTROPY; HORIZON
AB We present a model-independent method to test for scale-dependent non-Gaussianities in combination with scaling indices as test statistics. Therefore, surrogate data sets are generated, in which the power spectrum of the original data is preserved, while the higher order correlations are partly randomized by applying a scale-dependent shuffling procedure to the Fourier phases. We apply this method to the Wilkinson Microwave Anisotropy Probe data of the cosmic microwave background and find signatures for non-Gaussianities on large scales. Further tests are required to elucidate the origin of the detected anomalies.
C1 [Raeth, C.; Morfill, G. E.; Rossmanith, G.] Max Planck Inst Extraterr Phys, D-85748 Garching, Germany.
[Banday, A. J.] Ctr Etud Spatiale Rayonnements, F-31028 Toulouse, France.
[Gorski, K. M.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
[Gorski, K. M.] Univ Warsaw Observ, PL-00478 Warsaw, Poland.
RP Rath, C (reprint author), Max Planck Inst Extraterr Phys, Giessenbachstr 1, D-85748 Garching, Germany.
FU LAMBDA; NASA Office of Space Science.
FX We acknowledge the use of LAMBDA. Support for LAMBDA is provided by the
NASA Office of Space Science.
NR 29
TC 32
Z9 32
U1 0
U2 1
PU AMER 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 APR 3
PY 2009
VL 102
IS 13
AR 131301
DI 10.1103/PhysRevLett.102.131301
PG 4
WC Physics, Multidisciplinary
SC Physics
GA 428YS
UT WOS:000264888600011
PM 19392345
ER
PT J
AU Meador, MAB
Weber, AS
Hindi, A
Naumenko, M
McCorkle, L
Quade, D
Vivod, SL
Gould, GL
White, S
Deshpande, K
AF Meador, Mary Ann B.
Weber, Amanda S.
Hindi, Alia
Naumenko, Melanie
McCorkle, Linda
Quade, Derek
Vivod, Stephanie L.
Gould, George L.
White, Shannon
Deshpande, Kiranmayi
TI Structure-Property Relationships in Porous 3D Nanostructures:
Epoxy-Cross-Linked Silica Aerogels Produced Using Ethanol as the Solvent
SO ACS APPLIED MATERIALS & INTERFACES
LA English
DT Article
DE aerogel; polymer cross-linking; nanoporous materials; hybrid materials;
sol-gel
ID AMINE-MODIFIED SILICA; ORGANIC-INORGANIC MATERIALS; COMPOSITE AEROGELS;
TRANSPARENT; SOL
AB Cross-linking silica aerogels with organic groups has been shown to improve the strength over un-cross-linked aerogels by as much as 2 orders of magnitude. Previous cross-linking chemistry has been developed using solvents specifically chosen to dissolve the monomers and accommodate the reaction temperature. Because the process of making the aerogels requires so much solvent, it is of interest to consider less toxic solvents such as ethanol to increase safety and enhance scale up. To this end, two different epoxy precursors with suitable solubility in ethanol were evaluated as cross-linkers for silica gels prepared from (3-aminopropyl)triethoxysilane and tetraethylorthosilicate. In addition, 1,6-bis(trimethoxysilyl)hexane (BTMSH) was used as an additive in the underlying silica structure to add flexibility to the aerogels. it was found that the ethanol-derived aerogels exhibited more shrinkage than those prepared from other solvents but that including BTMSH in the aerogels significantly reduced this shrinkage. Inclusion of BTMSH also imparted the ability of the aerogel monoliths to recover elastically when compressed up to 50% strain. In addition, optimized cross-linked aerogels prepared in this study have mechanical properties comparable to those using other more undesirable solvents and cross-linkers.
C1 [Meador, Mary Ann B.; Quade, Derek; Vivod, Stephanie L.] NASA, Glenn Res Ctr, Cleveland, OH 44135 USA.
[Gould, George L.; White, Shannon; Deshpande, Kiranmayi] Aspen Aerogels, Northborough, MA 01532 USA.
RP Meador, MAB (reprint author), NASA, Glenn Res Ctr, 21000 Brookpk Rd, Cleveland, OH 44135 USA.
EM maryann.meador@nasa.gov
OI Meador, Mary Ann/0000-0003-2513-7372
FU NASA's Fundamental Aeronautics Program; Undergraduate Student Researcher
Program
FX we gratefully acknowledge financial support from NASA's Fundamental
Aeronautics Program, NASA's Innovative Partnerships Program, and the
Undergraduate Student Researcher Program. We thank Dr. Baochau N. Nguyen
of the Ohio Aerospace Institute for running solid NMR and Anna Palczer
for porosimetry measurements.
NR 23
TC 51
Z9 54
U1 6
U2 66
PU AMER CHEMICAL SOC
PI WASHINGTON
PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA
SN 1944-8244
J9 ACS APPL MATER INTER
JI ACS Appl. Mater. Interfaces
PD APR
PY 2009
VL 1
IS 4
BP 894
EP 906
DI 10.1021/am900014z
PG 13
WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary
SC Science & Technology - Other Topics; Materials Science
GA 464VM
UT WOS:000267536100022
PM 20356015
ER
PT J
AU Lin, Y
Watson, KA
Fallbach, MJ
Ghose, S
Smith, JG
Delozier, DM
Cao, W
Crooks, RE
Connell, JW
AF Lin, Yi
Watson, Kent A.
Fallbach, Michael J.
Ghose, Sayata
Smith, Joseph G., Jr.
Delozier, Donavon M.
Cao, Wei
Crooks, Roy E.
Connell, John W.
TI Rapid, Solventless, Bulk Preparation of Metal Nanoparticle-Decorated
Carbon Nanotubes
SO ACS NANO
LA English
DT Article
DE carbon nanotubes; metal decoration; nanohybrids; solventless; bulk
preparation
ID GRAPHITE COMPOSITE ELECTRODES; SURFACE-ENHANCED RAMAN;
THERMAL-DECOMPOSITION; PALLADIUM NANOPARTICLES; GOLD NANOPARTICLES;
CHARGE-TRANSFER; FUEL-CELLS; SINGLE; SILVER; SPECTROSCOPY
AB A rapid, solventless method is described for the decoration of carbon nanotubes with metal nanoparticles. The straightforward two-step process utilizes neither reducing agents nor electric current and involves the dry mixing of a precursor metal salt (e.g., a metal acetate) with carbon nanotubes (single- or multi-walled) followed by heating in an inert atmosphere. The procedure is scalable to multigram quantities and generally applicable to various other carbon substrates (e.g., carbon nanofiber, expanded graphite, and carbon black) and many metal salts (e.g., Ag, Au, Co, Ni, and Pd acetates). As a model system, Ag nanoparticle-decorated carbon nanotube samples were prepared under various mixing techniques, metal loading levels, thermal treatment temperatures, and nanotube oxidative acid treatments. These nanohybrids were characterized by a variety of microscopic and spectroscopic techniques. For example, X-ray diffraction and scanning electron microscopy indicated that the average size of the Ag nanoparticles has little to do with the thermal treatment temperature but can be easily controlled by varying the Ag loading. Raman spectroscopy illustrated both the metal-nanotube electronic interactions and the surface enhancement effect from the Ag nanoparticle attachment. High-resolution transmission electron microscopy captured the in situ salt-to-metal conversion events on the nanotube surface. The mechanistic implications from the characterization results are discussed.
C1 [Watson, Kent A.; Ghose, Sayata; Delozier, Donavon M.; Crooks, Roy E.] Natl Inst Aerospace, Hampton, VA 23666 USA.
[Smith, Joseph G., Jr.; Connell, John W.] NASA, Langley Res Ctr, Adv Mat & Proc Branch, Hampton, VA 23681 USA.
[Cao, Wei] Old Dominion Univ, Appl Res Ctr, Newport News, VA 23606 USA.
[Lin, Yi; Fallbach, Michael J.] NASA, Langley Res Ctr, Hampton, VA 23681 USA.
RP Lin, Y (reprint author), NASA, Langley Res Ctr, Hampton, VA 23681 USA.
EM yi.lin-1@nasa.gov; john.w.connell@nasa.gov
RI Cao, Wei/E-8950-2011
FU Oak Ridge Associated Universities [NNH06CC03B]
FX Y.L. and MJ.F. were supported by appointments to the NASA Postdoctoral
Program at the Langley Research Center, administered by Oak Ridge
Associated Universities (through NASA contract NNH06CC03B) and the
National Research Council, respectively. The authors thank D. Hartman
for XRD experiments, T. Williams for assistance in sample preparation
and particle size measurements, and Drs. P. Lillehei, A. Belcher, and C.
Wohl for their valuable comments and suggestions. The authors are in
debt to Prof. Y.-P. Sun and his research group at Clemson University for
their generous help in microscopy and other experiments, and Dr. J.
Hudson at Clemson University for XPS measurements.
NR 83
TC 130
Z9 133
U1 3
U2 95
PU AMER CHEMICAL SOC
PI WASHINGTON
PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA
SN 1936-0851
J9 ACS NANO
JI ACS Nano
PD APR
PY 2009
VL 3
IS 4
BP 871
EP 884
DI 10.1021/nn8009097
PG 14
WC Chemistry, Multidisciplinary; Chemistry, Physical; Nanoscience &
Nanotechnology; Materials Science, Multidisciplinary
SC Chemistry; Science & Technology - Other Topics; Materials Science
GA 439HR
UT WOS:000265618700019
PM 19278218
ER
PT J
AU Demoulin, P
Pariat, E
AF Demoulin, P.
Pariat, E.
TI Modelling and observations of photospheric magnetic helicity
SO ADVANCES IN SPACE RESEARCH
LA English
DT Article
DE Magnetic fields; Magnetic helicity; Magneto-hydrodynamic; Photosphere;
Corona; Coronal mass ejections
ID SOLAR ACTIVE REGIONS; LOCAL CORRELATION TRACKING; CORONAL MASS EJECTION;
MINIMUM ENERGY FIT; FLUX TUBES; INDUCTION EQUATION; VECTOR MAGNETOGRAMS;
INVERSE CASCADE; INJECTION; FIELDS
AB Mounting observational evidence of the emergence of twisted magnetic flux tubes through the photosphere have now been published. Such flux tubes, formed by the solar dynamo and transported through the convection zone, eventually reach the solar atmosphere. Their accumulation in the solar corona leads to flares and coronal mass ejections. Since reconnections occur during the evolution of the flux tubes, the concepts of twist and magnetic stress become inappropriate. Magnetic helicity, as a well preserved quantity, in particular in plasma with high magnetic Reynolds number, is a more suitable physical quantity to use, even if reconnection is involved.
Only recently, it has been realized that the flux of magnetic helicity can be derived from magnetogram time series. This paper reviews the advances made in measuring the helicity injection rate at the photospheric level, mostly in active regions. It relates the observations to our present theoretical understanding of the emergence process. Most of the helicity injection is found during magnetic flux emergence, whereas the effect of differential rotation is small, and the long-term evolution of active regions is still puzzling. The photospheric maps of the injection of magnetic helicity provide new spatial information about the basic properties of the link between the solar activity and its sub-photospheric roots. Finally, the newest techniques to measure photospheric flows arc reviewed. (C) 2008 COSPAR. Published by Elsevier Ltd. All rights reserved.
C1 [Demoulin, P.] Observ Paris, LESIA, CNRS, UMR 8109, F-92195 Meudon, France.
[Pariat, E.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
[Pariat, E.] George Mason Univ, Coll Sci, Fairfax, VA 22030 USA.
[Pariat, E.] USN, Res Lab, Washington, DC 20375 USA.
RP Demoulin, P (reprint author), Observ Paris, LESIA, CNRS, UMR 8109, F-92195 Meudon, France.
EM Pascal.Demoulin@obspm.fr; epariat@helio.gsfc.nasa.gov
OI Demoulin, Pascal/0000-0001-8215-6532
NR 89
TC 46
Z9 46
U1 1
U2 4
PU ELSEVIER SCI LTD
PI OXFORD
PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND
SN 0273-1177
J9 ADV SPACE RES
JI Adv. Space Res.
PD APR 1
PY 2009
VL 43
IS 7
BP 1013
EP 1031
DI 10.1016/j.asr.2008.12.004
PG 19
WC Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology &
Atmospheric Sciences
SC Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences
GA 430OW
UT WOS:000264999400001
ER
PT J
AU Inman, JA
Danehy, PM
Alderfer, DW
Buck, GM
McCrea, A
AF Inman, Jennifer A.
Danehy, Paul M.
Alderfer, David W.
Buck, Gregory M.
McCrea, Andrew
TI Planar Fluorescence Imaging and Three-Dimensional Reconstructions of
Capsule Reaction-Control-System Jets
SO AIAA JOURNAL
LA English
DT Article
ID LASER-INDUCED FLUORESCENCE; TEMPERATURE-MEASUREMENTS; STREAMWISE
VORTICES; FLOW; VISUALIZATION; LAYER; NO
AB Planar laser-induced-fluorescence flowfield visualization has been used to investigate reaction-control-system jet flows in the wake of hypersonic capsule reentry vehicles. Pitch, roll, and yaw reaction-control-system jets were all studied. Planar laser-induced fluorescence was used to obtain offbody How images at planar slices in these flowfields, which are not easily visualized by other techniques, owing to characteristically low gas density. When viewed individually, these slices are shown to provide spatially and temporally resolved information, including the locations and characteristics of turbulent How structures and the location of the jet flow relative to the vehicle. In addition, ensembles of slices acquired at multiple locations throughout the flowfield are combined using computer visualization techniques to reconstruct the three-dimensional shape of the flow. Collectively, the offbody flow-visualization data set acquired in these tests represents a valuable complement to surface measurements, especially as a basis for explaining otherwise perplexing discrepancies between such measurements and computational fluid dynamics results. The tests described herein were conducted in the 31-Inch Mach 10 Air Tunnel at NASA Langley Research Center.
C1 [Inman, Jennifer A.; Danehy, Paul M.; Alderfer, David W.] NASA, Langley Res Ctr, Adv Sensing & Opt Measurement Branch, Hampton, VA 23681 USA.
[McCrea, Andrew] Alliant Techsyst, Adv Sensing & Opt Measurement Branch, Space Div, Hampton, VA 23681 USA.
[Buck, Gregory M.] NASA, Langley Res Ctr, Aerothermodynam Branch, Hampton, VA 23681 USA.
RP Inman, JA (reprint author), NASA, Langley Res Ctr, Adv Sensing & Opt Measurement Branch, Mail Stop 493, Hampton, VA 23681 USA.
FU NASA Fundamental Aeronautics Program's Hypersonics Project; NASA's
Constellation Orion Crew Exploration Vehicle Aeroscience Program (CAP)
FX We wish to acknowledge the contribution to this project from the NASA
Langley Research Center 31-Inch Mach 10 Air Tunnel technicians and
engineers, including Anthony Robbins, Kevin Hollingsworth, Sheila
Wright, Paul Tucker, Henry Fitz Fitzgerald, Johnny Ellis, Stan Mason,
and Doug Boggs. This work was Supported by the NASA Fundamental
Aeronautics Program's Hypersonics Project as well as NASA's
Constellation Orion Crew Exploration Vehicle Aeroscience Program (CAP).
Thanks also to Richard Schwartz from Alliant Techsystems, Hampton,
Virginia, for assisting with the computer visualizations of the data.
NR 41
TC 7
Z9 7
U1 0
U2 1
PU AMER INST AERONAUTICS ASTRONAUTICS
PI RESTON
PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA
SN 0001-1452
EI 1533-385X
J9 AIAA J
JI AIAA J.
PD APR
PY 2009
VL 47
IS 4
BP 803
EP 812
DI 10.2514/1.37116
PG 10
WC Engineering, Aerospace
SC Engineering
GA 432SA
UT WOS:000265153200002
ER
PT J
AU Watkins, AN
Buck, GM
Leighty, BD
Lipford, WE
Oglesby, DM
AF Watkins, A. Neal
Buck, Gregory M.
Leighty, Bradley D.
Lipford, William E.
Oglesby, Donald M.
TI Using Pressure- and Temperature-Sensitive Paint on the Aftbody of a
Capsule Vehicle
SO AIAA JOURNAL
LA English
DT Article
ID HEAT-TRANSFER
AB Pressure-sensitive and temperature-sensitive paint were used to visualize and quantify the surface interactions of reaction control system jets on the afthody of capsule reentry vehicle shapes. The first model tested was an Apollo-like configuration and was used to focus primarily on the effects of the forward facing roll and yaw jets. The second model tested was an early Orion crew module configuration blowing only out of its forward-most yaw jet, which was expected to have the most intense aerodynamic heating augmentation on the model surface. This paper will present the results from the experiments, which show that with proper system design, both pressure-sensitive and temperature-sensitive paint are effective tools for studying these types of interaction in hypersonic testing environments.
C1 [Watkins, A. Neal; Leighty, Bradley D.; Lipford, William E.] NASA, Langley Res Ctr, Adv Sensing & Opt Measurement Branch, Hampton, VA 23681 USA.
[Buck, Gregory M.] NASA, Langley Res Ctr, Aerothermodynam Branch, Hampton, VA 23681 USA.
[Oglesby, Donald M.] ATK Aerospace Co, Hampton, VA 23681 USA.
RP Watkins, AN (reprint author), NASA, Langley Res Ctr, Adv Sensing & Opt Measurement Branch, Mail Stop 493, Hampton, VA 23681 USA.
NR 34
TC 5
Z9 5
U1 1
U2 6
PU AMER INST AERONAUTICS ASTRONAUTICS
PI RESTON
PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA
SN 0001-1452
EI 1533-385X
J9 AIAA J
JI AIAA J.
PD APR
PY 2009
VL 47
IS 4
BP 821
EP 829
DI 10.2514/1.37258
PG 9
WC Engineering, Aerospace
SC Engineering
GA 432SA
UT WOS:000265153200004
ER
PT J
AU Mielke, AF
Elam, KA
Sung, CJ
AF Mielke, Amy F.
Elam, Kristie A.
Sung, Chih-Jen
TI Multiproperty Measurements at High Sampling Rates Using Rayleigh
Scattering
SO AIAA JOURNAL
LA English
DT Article
ID BRILLOUIN-SCATTERING; TEMPERATURE; DENSITY; FLOWS; GAS; FLUCTUATIONS;
THERMOMETRY; VELOCIMETRY
AB A molecular Rayleigh scattering technique is developed to measure gas velocity, temperature, and density in unseeded gas flows at sampling rates up to 32 kHz. A high-power continuous-wave laser beam is focused at a point in an air flowfield, and Rayleigh scattered light is collected and fiber-optically transmitted to a Fabry-Perot interferometer for spectral analysis. Photomultiplier tubes operated in the photon-counting mode allow high-frequency sampling of the total signal level and the circular interference pattern to provide density, temperature, and velocity measurements. Mean and root-mean-square fluctuation measurements in both an electrically heated jet facility with a 10-mm-diam nozzle and in a hydrogen-combustor-heated-jet facility with a 50.8-mm-diam nozzle at NASA John H. Glenn Research Center at Lewis Field are presented. Measurements are compared with hot-wire anemometry, cold-wire thermometry, and temporally resolved particle image velocimetry to validate the Rayleigh technique.
C1 [Mielke, Amy F.] NASA, John H Glenn Res Ctr Lewis Field, Opt Instrumentat & Nondestruct Evaluat Branch, Cleveland, OH 44135 USA.
[Elam, Kristie A.] Jacobs Sverdrup, Cleveland, OH 44135 USA.
[Sung, Chih-Jen] Case Western Reserve Univ, Dept Mech & Aerosp Engn, Cleveland, OH 44106 USA.
RP Mielke, AF (reprint author), NASA, John H Glenn Res Ctr Lewis Field, Opt Instrumentat & Nondestruct Evaluat Branch, 21000 Brookpk Rd,Mail Stop 77-1, Cleveland, OH 44135 USA.
NR 34
TC 7
Z9 7
U1 0
U2 1
PU AMER INST AERONAUTICS ASTRONAUTICS
PI RESTON
PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA
SN 0001-1452
EI 1533-385X
J9 AIAA J
JI AIAA J.
PD APR
PY 2009
VL 47
IS 4
BP 850
EP 862
DI 10.2514/1.37369
PG 13
WC Engineering, Aerospace
SC Engineering
GA 432SA
UT WOS:000265153200007
ER
PT J
AU Rumsey, CL
Spalart, PR
AF Rumsey, Christopher L.
Spalart, Philippe R.
TI Turbulence Model Behavior in Low Reynolds Number Regions of Aerodynamic
Flowfields
SO AIAA JOURNAL
LA English
DT Article
ID BOUNDARY-LAYERS; PREDICTING TRANSITION; UNSTRUCTURED GRIDS; AIRFOIL
FLOWS; HIGH-LIFT; EQUATION
AB The behaviors of the widely used Spalart-Allmaras and Menter shear-stress transport turbulence models at low Reynolds numbers and under conditions conducive to relaminarization are documented. The flows used in the investigation include 2-D zero-pressure-gradient flow over a flat plate from subsonic to hypersonic Mach numbers, 2- airfoil flow from subsonic to supersonic Mach numbers, 2-D subsonic sink flow, and 3-D subsonic flow over an infinite swept wing (particularly its leading-edge region). Both models exhibit a range over which they behave "transitionally" even with inflow values set to cause immediate growth of the turbulence quantities, in the sense that the flow is neither laminar nor fully turbulent, but these behaviors are different: the shear-stress transport model typically has a well-defined transition location, whereas the Spalart-Allmaras model does not. Both models are predisposed to delayed activation of turbulence with increasing freestream Mach number. Also, both models can be made to achieve earlier activation of turbulence by increasing their freestream levels, but too high a level can disturb the turbulent solution behavior. The technique of maintaining freestream levels of turbulence without decay in the shear-stress transport model, introduced elsewhere, is shown here to be useful in reducing grid dependence of the model's transitional behavior. Both models are demonstrated to be incapable of predicting relaminarization; eddy viscosities remain weakly turbulent in accelerating or laterally strained boundary layers for which experiment and direct simulations indicate turbulence suppression. The main conclusion is that these models are intended for fully turbulent high Reynolds number computations, and using them for transitional (e.g., low Reynolds number) or relaminarizing flows is not appropriate. Competing models which fare better in these areas have not been identified.
C1 [Rumsey, Christopher L.] NASA, Langley Res Ctr, Computat Aerosci Branch, Hampton, VA 23681 USA.
RP Rumsey, CL (reprint author), NASA, Langley Res Ctr, Computat Aerosci Branch, Mail Stop 128, Hampton, VA 23681 USA.
NR 39
TC 23
Z9 24
U1 2
U2 7
PU AMER INST AERONAUT ASTRONAUT
PI RESTON
PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA
SN 0001-1452
J9 AIAA J
JI AIAA J.
PD APR
PY 2009
VL 47
IS 4
BP 982
EP 993
DI 10.2514/1.39947
PG 12
WC Engineering, Aerospace
SC Engineering
GA 432SA
UT WOS:000265153200020
ER
PT J
AU Smith, SM
Gardner, KK
Locke, J
Zwart, SR
AF Smith, Scott M.
Gardner, Keri K.
Locke, James
Zwart, Sara R.
TI Vitamin D supplementation during Antarctic winter
SO AMERICAN JOURNAL OF CLINICAL NUTRITION
LA English
DT Article
ID CELL-MEDIATED-IMMUNITY; SERUM-LEVELS; OLDER-ADULTS; D DEFICIENCY;
25-HYDROXYVITAMIN-D; DISEASE; OSTEOPOROSIS; POPULATION; PREVALENCE;
WOMEN
AB Background: Persons with limited exposure to ultraviolet B light, including space travelers, may not receive enough vitamin D. Recent studies indicate that optimal serum 25-hydroxyvitamin D [25(OH) D] should be >= 80 nmol/L.
Objective: This study was designed to evaluate the effectiveness of 3 doses of vitamin D to raise and maintain 25(OH) D to a concentration.80 nmol/L in persons with limited ultraviolet B light exposure.
Design: This was a 5-mo, prospective, randomized, double-blind study of vitamin D supplementation. It was conducted during winter in Antarctica at the McMurdo Station, when ultraviolet B radiation levels are essentially zero. The 55 subjects were randomly divided into 3 groups for vitamin D supplementation: 2000 IU/d (n = 18), 1000 IU/d (n = 19), and 400 IU/d (n = 18). An additional 7 subjects did not take supplements or took supplements of their own choosing. Blood samples were collected about every 2 mo during the winter.
Results: About 5 mo after supplementation started, 25(OH)D increased to 71 +/- 23 nmol/L in the 2000-IU/d group, 63 +/- 25 nmol/L in the 1000-IU/d group, and 57 +/- 15 nmol/L in the 400-IU/d group and decreased to 34 +/- 12 nmol/L in the group not taking supplements.
Conclusions: These data will enable us to provide space crews with evidence-based recommendations for vitamin D supplementation. The findings also have implications for other persons with limited ultraviolet light exposure, including polar workers and the elderly. Am J Clin Nutr 2009; 89:1092-8.
C1 [Smith, Scott M.; Locke, James] NASA, Lyndon B Johnson Space Ctr, Space Life Sci Directorate, Houston, TX 77058 USA.
[Gardner, Keri K.] Univ Calif Los Angeles, Sch Med, Los Angeles, CA USA.
[Gardner, Keri K.] VA Greater Los Angeles Hlth Care Syst, Los Angeles, CA USA.
[Zwart, Sara R.] Univ Space Res Assoc, Houston, TX USA.
RP Smith, SM (reprint author), NASA, Lyndon B Johnson Space Ctr, Space Life Sci Directorate, Mail Code SK3,2101 NASA Pkwy, Houston, TX 77058 USA.
EM scott.m.smith@nasa.gov
FU NASA; National Science Foundation
FX Supported by the NASA Human Research Program and made possible by the
National Science Foundation.
NR 46
TC 43
Z9 44
U1 0
U2 6
PU AMER SOC CLINICAL NUTRITION
PI BETHESDA
PA 9650 ROCKVILLE PIKE, SUBSCRIPTIONS, RM L-3300, BETHESDA, MD 20814-3998
USA
SN 0002-9165
J9 AM J CLIN NUTR
JI Am. J. Clin. Nutr.
PD APR 1
PY 2009
VL 89
IS 4
BP 1092
EP 1098
DI 10.3945/ajcn.2008.27189
PG 7
WC Nutrition & Dietetics
SC Nutrition & Dietetics
GA 420WF
UT WOS:000264319200016
PM 19225122
ER
PT J
AU Hurowitz, JA
Tosca, NJ
Dyar, MD
AF Hurowitz, Joel A.
Tosca, Nicholas J.
Dyar, M. Darby
TI Acid production by FeSO4 center dot nH(2)O dissolution and implications
for terrestrial and martian aquatic systems
SO AMERICAN MINERALOGIST
LA English
DT Article
DE Mars; AMD; melanterite; pH; Mossbauer
ID X-RAY SPECTROMETER; THERMODYNAMIC BEHAVIOR; THEORETICAL PREDICTION;
AQUEOUS ELECTROLYTES; MERIDIANI-PLANUM; SULFATE MINERALS; HIGH
PRESSURES; IRON MOUNTAIN; MARS; TEMPERATURES
AB Combined experimental, modeling, and analytical results indicate that the rapid acidification of dilute waters in contact with nominally Fe2+-sulfate minerals (FeSO4 center dot nH(2)O) is caused by Fe3+ hydrolysis, which occurs when low levels (<1 mol%) of a contaminant Fe3+-sulfate phase are dissolved along with the FeSO4 center dot nH(2)O. This rapid acidification has previously been attributed to hydrolysis by Fe2+. However, dissolution experiments performed using ZnSO4 center dot nH(2)O, in which the Zn2+ cation has a higher hydrolysis constant (log K = -8.96) than Fe2+ (log K = -9.5), failed to produce significant changes in solution pH. We present the results of geochemical modeling simulations confirming that FeSO4 center dot nH(2)O dissolution alone cannot explain the experimentally observed change in pH from 5.65 to 3.50. Nor can the experimental observations be explained by oxidation of Fe2+ to Fe 31 in solution. Instead, our experimental results can be best explained by modeling the incorporation of <1 mol% Fe3+ contamination from any number of Fe3+ or mixed valence Fe-sulfate phases, including anhydrous Fe-2(3+)(SO4)(3), coquimbite, kornelite, romerite, bilinite, copiapite, or ferricopiapite, all of which are reasonable candidate phases for oxidative breakdown products of FeSO4 center dot nH(2)O. Laboratory Mossbauer spectra are consistent with Lip to 0.6 mol% of the total Fe in the sample to be present as Fe3+. Although the doublet has parameters that are not diagnostic of any specific Fe3+-sulfate, they do help constrain its identification. These results demonstrate that minor contamination of labile Fe2+ sulfates by Fe3+ can have dramatic effects on solution chemistry that should be considered when studying reactions relevant to acid mine drainage waste sites and other localities where Fe-sulfate minerals occur, such as the surface of Mars.
C1 [Hurowitz, Joel A.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
[Tosca, Nicholas J.] Harvard Univ, Dept Organism & Evolutionary Biol, Cambridge, MA 02138 USA.
[Dyar, M. Darby] Mt Holyoke Coll, Dept Astron, S Hadley, MA 01075 USA.
RP Hurowitz, JA (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA.
EM joel.a.hurowitz@jpl.nasa.gov
FU Jet Propulsion Laboratory, California Institute of Technology; NASA
[NNX06AB62G]
FX This work was carried out at the Jet Propulsion Laboratory, California
Institute of Technology, under a contract with NASA. This work was also
supported by NASA grant NNX06AB62G, and an Origins Initiative
Postdoctoral Fellowship to N.J.T. We thank Albert Yen for the use
oflaboratory facilities. and WilliamAbbey for assistance with XRD data
collection.
NR 35
TC 11
Z9 11
U1 2
U2 10
PU MINERALOGICAL SOC AMER
PI CHANTILLY
PA 3635 CONCORDE PKWY STE 500, CHANTILLY, VA 20151-1125 USA
SN 0003-004X
EI 1945-3027
J9 AM MINERAL
JI Am. Miner.
PD APR
PY 2009
VL 94
IS 4
BP 409
EP 414
DI 10.2138/am.2009.3085
PG 6
WC Geochemistry & Geophysics; Mineralogy
SC Geochemistry & Geophysics; Mineralogy
GA 432TL
UT WOS:000265157000001
ER
PT J
AU Chiesl, TN
Chu, WK
Stockton, AM
Amashukeli, X
Grunthaner, F
Mathies, RA
AF Chiesl, Thomas N.
Chu, Wai K.
Stockton, Amanda M.
Amashukeli, Xenia
Grunthaner, Frank
Mathies, Richard A.
TI Enhanced Amine and Amino Acid Analysis Using Pacific Blue and the Mars
Organic Analyzer Microchip Capillary Electrophoresis System
SO ANALYTICAL CHEMISTRY
LA English
DT Article
ID MURCHISON METEORITE; EXTRATERRESTRIAL EXPLORATION; CARBONACEOUS
CHONDRITES; BIOMARKER DETECTION; PARENT BODY; SURFACE; CHROMATOGRAPHY;
SEPARATIONS; MICRODEVICE; MICELLES
AB The fluorescent amine reactive probe Pacific Blue succinimidyl ester (PB) is used for the detection of trace amounts of amines and amino acids by microchip capillary electrophoresis on the Mars Organic Analyzer (MOA). The spectral and chemical properties of PB provide a 200-fold increase in sensitivity and improved resolution compared to fluorescamine derivatization. With the use of cross injection and PB labeling, the MOA detected amino acids at concentrations as low as 75 pM (sub-parts-per-trillion). Micellar electrokinetic chromatograpy (MEKC) which separates PB-labeled amino acids by their hydro-phobicity is also demonstrated. The optimized MEKC conditions (45 mM CHAPSO, pH 6 at 5 degrees C) effectively separated amines and 25 amino acids with enantiomeric resolution of alanine, serine, and citrulline. Samples from the Yungay Hills region in the Atacama Desert, Chile and from the Murchison meteorite are successfully analyzed using both techniques, and amino acids are found in the parts-per-billion range. Abiotic amino acids such as beta-alanine and epsilon-aminocaprioc acid are detected along with several neutral and acidic amino acids in the Murchison sample. The Atacama Desert sample is found to contain homochiral L-alanine and L-serine indicating the presence of extant or recently extinct life.
C1 [Chiesl, Thomas N.; Chu, Wai K.; Stockton, Amanda M.; Mathies, Richard A.] Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA.
[Amashukeli, Xenia; Grunthaner, Frank] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
RP Mathies, RA (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA.
EM ramathies@berkeley.edu
RI Stockton, Amanda/C-1173-2012
FU NASA [NNG04GB75G, NNX08AR09G]; Jet Propulsion Laboratory at Cal Tech
[1297596]
FX We acknowledge the assistance of the international Urey Instrument Team
as well as the ASAP participants in the course of this research.
Microfabrication was carried out at the University of California,
Berkeley, Microfabrication Laboratory. This research was supported by
NASA Grants NNG04GB75G and NNX08AR09G and by the Jet Propulsion
Laboratory at Cal Tech under contract no.1297596.
NR 41
TC 50
Z9 51
U1 4
U2 27
PU AMER CHEMICAL SOC
PI WASHINGTON
PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA
SN 0003-2700
EI 1520-6882
J9 ANAL CHEM
JI Anal. Chem.
PD APR 1
PY 2009
VL 81
IS 7
BP 2537
EP 2544
DI 10.1021/ac8023334
PG 8
WC Chemistry, Analytical
SC Chemistry
GA 427DG
UT WOS:000264759400017
PM 19245228
ER
PT J
AU Blum, JS
Han, S
Lanoil, B
Saltikov, C
Witte, B
Tabita, FR
Langley, S
Beveridge, TJ
Jahnke, L
Oremland, RS
AF Blum, Jodi Switzer
Han, Sukkyun
Lanoil, Brian
Saltikov, Chad
Witte, Brian
Tabita, F. Robert
Langley, Sean
Beveridge, Terry J.
Jahnke, Linda
Oremland, Ronald S.
TI Ecophysiology of "Halarsenatibacter silvermanii" Strain SLAS-1(T), gen.
nov., sp nov., a Facultative Chemoautotrophic Arsenate Respirer from
Salt-Saturated Searles Lake, California
SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY
LA English
DT Article
ID 16S RIBOSOMAL-RNA; GRADIENT GEL-ELECTROPHORESIS; SULFATE-REDUCING
BACTERIA; SODA LAKES; MONO LAKE; DISSIMILATORY ARSENATE; FATTY-ACIDS;
MEMBRANE-LIPIDS; SEQUENCE DATA; REDUCTION
AB Searles Lake occupies a closed basin harboring salt-saturated, alkaline brines that have exceptionally high concentrations of arsenic oxyanions. Strain SLAS-1(T) was previously isolated from Searles Lake (R. S. Orem-land, T. R. Kulp, J. Switzer Blum, S. E. Hoeft, S. Baesman, L. G. Miller, and J. F. Stolz, Science 308: 1305-1308, 2005). We now describe this extremophile with regard to its substrate affinities, its unusual mode of motility, sequenced arrABD gene cluster, cell envelope lipids, and its phylogenetic alignment within the order Halanaero-bacteriales, assigning it the name "Halarsenatibacter silvermanii" strain SLAS-1(T). We also report on the substrate dynamics of an anaerobic enrichment culture obtained from Searles Lake that grows under conditions of salt saturation and whose members include a novel sulfate reducer of the order Desulfovibriales, the archaeon Halorhabdus utahensis, as well as a close homolog of strain SLAS-1(T).
C1 [Blum, Jodi Switzer; Oremland, Ronald S.] US Geol Survey, Menlo Pk, CA 94025 USA.
[Han, Sukkyun] Univ Calif Riverside, Dept Environm Sci, Riverside, CA 92521 USA.
[Lanoil, Brian] Univ Alberta, Dept Biol Sci, Edmonton, AB T6G 2E1, Canada.
[Saltikov, Chad] Univ Calif Santa Cruz, Dept Microbiol & Environm Toxicol, Santa Cruz, CA 95064 USA.
[Witte, Brian; Tabita, F. Robert] Ohio State Univ, Dept Microbiol, Columbus, OH 43210 USA.
[Langley, Sean] Univ Ottawa, Dept Earth Sci, Ottawa, ON K1N 6N5, Canada.
[Beveridge, Terry J.] Univ Guelph, Dept Mol & Cellular Biol, Guelph, ON N1G 2W1, Canada.
[Jahnke, Linda] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA.
RP Oremland, RS (reprint author), US Geol Survey, MS 480,345 Middlefield Rd, Menlo Pk, CA 94025 USA.
EM roremlan@usgs.gov
OI Lanoil, Brian/0000-0001-8603-8330
FU USGS
FX This work was supported by the USGS National Research Program and by a
NASA Exobiology grant. We are indebted to H. Truper with his help with
the epithet.; We are grateful to J. Stolz, C. Pearce, and R. Sierra for
constructive criticism of earlier drafts of the manuscript. The TEMs
were conducted by S. L. and T. J. B. at the University of Guelph.
NR 65
TC 22
Z9 24
U1 0
U2 16
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 APR 1
PY 2009
VL 75
IS 7
BP 1950
EP 1960
DI 10.1128/AEM.02614-08
PG 11
WC Biotechnology & Applied Microbiology; Microbiology
SC Biotechnology & Applied Microbiology; Microbiology
GA 424EX
UT WOS:000264549400019
PM 19218420
ER
PT J
AU Gatewood, AG
Liebman, KA
Vourc'h, G
Bunikis, J
Hamer, SA
Cortinas, R
Melton, F
Cislo, P
Kitron, U
Tsao, J
Barbour, AG
Fish, D
Diuk-Wasser, MA
AF Gatewood, Anne G.
Liebman, Kelly A.
Vourc'h, Gwenael
Bunikis, Jonas
Hamer, Sarah A.
Cortinas, Roberto
Melton, Forrest
Cislo, Paul
Kitron, Uriel
Tsao, Jean
Barbour, Alan G.
Fish, Durland
Diuk-Wasser, Maria A.
TI Climate and Tick Seasonality Are Predictors of Borrelia burgdorferi
Genotype Distribution
SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY
LA English
DT Article
ID IXODES-SCAPULARIS ACARI; EARLY LYME-DISEASE; SENSU-STRICTO STRAINS;
MEDIUM-SIZED MAMMALS; WHITE-FOOTED MICE; SOUTHERN NEW-YORK;
UNITED-STATES; HEMATOGENOUS DISSEMINATION; POPULATION-DYNAMICS; RABIES
VIRUS
AB The blacklegged tick, Ixodes scapularis, is of significant public health importance as a vector of Borrelia burgdorferi, the agent of Lyme borreliosis. The timing of seasonal activity of each immature I. scapularis life stage relative to the next is critical for the maintenance of B. burgdorferi because larvae must feed after an infected nymph to efficiently acquire the infection from reservoir hosts. Recent studies have shown that some strains of B. burgdorferi do not persist in the primary reservoir host for more than a few weeks, thereby shortening the window of opportunity between nymphal and larval feeding that sustains their enzootic maintenance. We tested the hypothesis that climate is predictive of geographic variation in the seasonal activity of I. scapularis, which in turn differentially influences the distribution of B. burgdorferi genotypes within the geographic range of I. scapularis. We analyzed the relationships between climate, seasonal activity of I. scapularis, and B. burgdorferi genotype frequency in 30 geographically diverse sites in the northeastern and midwestern United States. We found that the magnitude of the difference between summer and winter daily temperature maximums was positively correlated with the degree of seasonal synchrony of the two immature stages of I. scapularis. Genotyping revealed an enrichment of 16S-23S rRNA intergenic spacer restriction fragment length polymorphism sequence type 1 strains relative to others at sites with lower seasonal synchrony. We conclude that climate-associated variability in the timing of I. scapularis host seeking contributes to geographic heterogeneities in the frequencies of B. burgdorferi genotypes, with potential consequences for Lyme borreliosis morbidity.
C1 [Gatewood, Anne G.; Liebman, Kelly A.; Cislo, Paul; Fish, Durland; Diuk-Wasser, Maria A.] Yale Univ, Sch Med, Dept Epidemiol & Publ Hlth, New Haven, CT 06520 USA.
[Vourc'h, Gwenael] Natl Inst Agr Res, Anim Epidemiol UR346, F-63122 St Genes Champanelle, France.
[Bunikis, Jonas; Barbour, Alan G.] Univ Calif Irvine, Dept Microbiol & Mol Genet, Irvine, CA 92697 USA.
[Hamer, Sarah A.; Tsao, Jean] Michigan State Univ, Dept Fisheries & Wildlife, E Lansing, MI 48824 USA.
[Cortinas, Roberto] Univ Nebraska, Dept Entomol, Lincoln, NE 68583 USA.
[Melton, Forrest] Calif State Univ Monterey Bay, Div Sci & Environm Policy, Seaside, CA 93955 USA.
[Melton, Forrest] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA.
[Kitron, Uriel] Emory Univ, Dept Environm Studies, Atlanta, GA 30322 USA.
[Tsao, Jean] Michigan State Univ, Dept Large Anim Clin Sci, E Lansing, MI 48824 USA.
RP Diuk-Wasser, MA (reprint author), 60 Coll St,POB 208034, New Haven, CT 06520 USA.
EM maria.diuk@yale.edu
RI Barbour, Alan/B-3160-2009
OI Barbour, Alan/0000-0002-0719-5248
FU U. S. Centers for Disease Control and Prevention (CDC) [5U01CI00
0171-04]; U. S. Department of Agriculture Agricultural Research Service
[58-0790-5-068]; G. Harold and Leila Y. Mathers Foundation
FX This research was supported by the U. S. Centers for Disease Control and
Prevention (CDC) under cooperative agreement no. 5U01CI00 0171-04, the
U. S. Department of Agriculture Agricultural Research Service under
cooperative agreement no. 58-0790-5-068, and the G. Harold and Leila Y.
Mathers Foundation. A. G. G. acknowledges support from the CDC
Fellowship Training Program in Vector-Borne Diseases.
NR 62
TC 79
Z9 81
U1 0
U2 41
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 APR
PY 2009
VL 75
IS 8
BP 2476
EP 2483
DI 10.1128/AEM.02633-08
PG 8
WC Biotechnology & Applied Microbiology; Microbiology
SC Biotechnology & Applied Microbiology; Microbiology
GA 429RC
UT WOS:000264936800028
PM 19251900
ER
PT J
AU Nixon, CA
Teanby, NA
Calcutt, SB
Aslam, S
Jennings, DE
Kunde, VG
Flasar, FM
Irwin, PGJ
Taylor, FW
Glenar, DA
Smith, MD
AF Nixon, Conor A.
Teanby, Nicholas A.
Calcutt, Simon B.
Aslam, Shahid
Jennings, Donald E.
Kunde, Virgil G.
Flasar, F. Michael
Irwin, Patrick G. J.
Taylor, Fredric W.
Glenar, David A.
Smith, Michael D.
TI Infrared limb sounding of Titan with the Cassini Composite InfraRed
Spectrometer: effects of the mid-IR detector spatial responses
SO APPLIED OPTICS
LA English
DT Article
ID ISOTOPIC-RATIOS; RADIATIVE-TRANSFER; ATMOSPHERE; CIRS; HC3N; HCN;
HYDROCARBONS; STRATOSPHERE; PROFILES; SPECTRA
AB The composite infrared spectrometer (CIRS) instrument on board the Cassini Saturn orbiter employs two 1 x 10 HgCdTe detector arrays for mid-infrared remote sensing of Titan's and Saturn's atmospheres. In this paper we show that the real detector spatial response functions, as measured in ground testing before launch, differ significantly from idealized "boxcar" responses. We further show that neglecting this true spatial response function when modeling CIRS spectra can have a significant effect on interpretation of the data, especially in limb-sounding mode, which is frequently used for Titan science. This result has implications not just for CIRS data analysis but for other similar instrumental applications. (C) 2009 Optical Society of America
C1 [Nixon, Conor A.; Kunde, Virgil G.] Univ Maryland, Dept Astron, College Pk, MD 20742 USA.
[Nixon, Conor A.; Aslam, Shahid; Jennings, Donald E.; Kunde, Virgil G.; Flasar, F. Michael; Glenar, David A.; Smith, Michael D.] NASA, Goddard Space Flight Ctr, Planetary Syst Branch, Greenbelt, MD 20771 USA.
[Teanby, Nicholas A.; Calcutt, Simon B.; Irwin, Patrick G. J.; Taylor, Fredric W.] Univ Oxford, Clarendon Lab, Subdept Atmospher Ocean & Planetary Phys, Oxford OX1 3PU, England.
[Aslam, Shahid] MEI Technol Inc, Houston, TX 77058 USA.
RP Nixon, CA (reprint author), Univ Maryland, Dept Astron, College Pk, MD 20742 USA.
EM conor.a.nixon@nasa.gov
RI Nixon, Conor/A-8531-2009; Flasar, F Michael/C-8509-2012; Smith,
Michael/C-8875-2012; Aslam, Shahid/D-1099-2012; Jennings,
Donald/D-7978-2012;
OI Nixon, Conor/0000-0001-9540-9121; Calcutt, Simon/0000-0002-0102-3170;
Teanby, Nicholas/0000-0003-3108-5775; Irwin, Patrick/0000-0002-6772-384X
FU Particle Physics and Astronomy Research Council (PPARC); Science and
Technology Facilities Council (STFC); NASA Cassini
FX The work described in this paper-including original laboratory
measurements and current analysis-was funded by the Particle Physics and
Astronomy Research Council (PPARC) and its successor, the Science and
Technology Facilities Council (STFC) for the UK component, and in the
U.S. by the NASA Cassini project, through their support for the design,
build, and operation of the CIRS instrument. We are grateful for the
helpful comments provided to us by two anonymous referees.
NR 22
TC 16
Z9 16
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 APR 1
PY 2009
VL 48
IS 10
BP 1912
EP 1925
DI 10.1364/AO.48.001912
PG 14
WC Optics
SC Optics
GA 436VH
UT WOS:000265443700050
PM 19340146
ER
PT J
AU Schafer, J
Lyons, W
Tong, WG
Danehy, PM
AF Schafer, J.
Lyons, W.
Tong, W. G.
Danehy, P. M.
TI Kinetic temperature and electron density measurement in an inductively
coupled plasma torch using degenerate four-wave mixing
SO APPLIED PHYSICS B-LASERS AND OPTICS
LA English
DT Article
ID ATMOSPHERIC-PRESSURE PLASMAS; SPECTROSCOPY; DIAGNOSTICS
AB Laser wave mixing is presented as an effective technique for spatially resolved kinetic temperature measurements in an atmospheric-pressure radio-frequency inductively coupled plasma. Measurements are performed in a 1 kW, 27 MHz radio-frequency plasma using a continuous-wave, tunable 811.5 nm diode laser to excite the 4s(3)P(2)-> 4p(3)D(3) argon transition. Kinetic temperature measurements are made at five radial steps from the center of the torch and at four different torch heights. The kinetic temperature is determined by measuring simultaneously the line shape of the sub-Doppler backward phase-conjugate degenerate four-wave mixing and the Doppler broadened forward-scattering degenerate four-wave mixing. The temperature measurements result in a range of 3,500 to 14,000 +/- 150 K. Electron densities measured range from 6.1 (+/- 0.3)x10(15) cm(-3) to 10.1 (+/- 0.3)x10(15) cm(-3). The experimental spectra are analyzed using a perturbative treatment of the backward phase-conjugate and forward-geometry wave-mixing theory. The Stark width is determined from the collisional broadening measured in the phase-conjugate geometry. Electron density measurements are made based on the Stark width. The kinetic temperature of the plasma was found to be more than halved by adding deionized water through the nebulizer.
C1 [Schafer, J.; Lyons, W.; Tong, W. G.] San Diego State Univ, Dept Chem & Biochem, San Diego, CA 92182 USA.
[Danehy, P. M.] NASA, Langley Res Ctr, Adv Sensing & Opt Measurement Branch, Hampton, VA 23681 USA.
RP Tong, WG (reprint author), San Diego State Univ, Dept Chem & Biochem, San Diego, CA 92182 USA.
EM william.tong@sdsu.edu
FU National Institute of General Medical Sciences, National Institutes of
Health [5-R01-GM41032]; Varian, Inc
FX We gratefully acknowledge partial support of this work from the National
Institute of General Medical Sciences, National Institutes of Health
under Grant No. 5-R01-GM41032, and Varian, Inc.
NR 20
TC 2
Z9 2
U1 1
U2 4
PU SPRINGER
PI NEW YORK
PA 233 SPRING ST, NEW YORK, NY 10013 USA
SN 0946-2171
J9 APPL PHYS B-LASERS O
JI Appl. Phys. B-Lasers Opt.
PD APR
PY 2009
VL 95
IS 1
BP 161
EP 168
DI 10.1007/s00340-009-3440-0
PG 8
WC Optics; Physics, Applied
SC Optics; Physics
GA 422XM
UT WOS:000264461000022
ER
PT J
AU Poulet, F
Beaty, DW
Bibring, JP
Bish, D
Bishop, JL
Dobrea, EN
Mustard, JF
Petit, S
Roach, LH
AF Poulet, Francois
Beaty, David W.
Bibring, Jean-Pierre
Bish, David
Bishop, Janice L.
Dobrea, Eldar Noe
Mustard, John F.
Petit, Sabine
Roach, Leah H.
TI Key Scientific Questions and Key Investigations from the First
International Conference on Martian Phyllosilicates
SO ASTROBIOLOGY
LA English
DT Article
DE Mars; Mineralogy; Space exploration; Phyllosilicates; Prebiotic
chemistry
ID MARS SOIL; REFLECTANCE SPECTROSCOPY; AQUEOUS ALTERATION; HOMOIONIC
CLAYS; SMECTITE CLAYS; MINERALS; ENVIRONMENT; LIFE; MICROORGANISMS;
NUCLEOTIDES
AB Minerals and their occurrences can tell us about the chemistry, pressure, and temperatures of past environments on Mars and thus allow inferences about the potential for habitability. Thanks to recent space exploration, a new vision is emerging wherein Mars hosted environmental conditions of potential astrobiological relevance. This epoch is identified by the presence of phyllosilicate-bearing deposits, which are generally contained in very ancient basement rocks. In October 2008, over 100 planetary scientists representing 11 countries met in Paris to assess and discuss the relevance of martian phyllosilicates. The conference was structured to promote the discussion and debate of key scientific questions and key essential investigations. The purpose of this report is to document the current state of knowledge related to martian phyllosilicates and to ascertain which questions remain to be addressed: What are the basic characteristics of the phyllosilicate minerals on Mars? What are the genetic mechanisms by which phyllosilicate minerals have formed on Mars? What is the relationship between the phyllosilicate minerals observed in martian meteorites and those detected from orbit? What are the implications of phyllosilicate-bearing rocks for the development of prebiotic chemistry and the preservation of biosignatures? The most promising investigations to address these questions are presented.
C1 [Poulet, Francois; Bibring, Jean-Pierre] Univ Paris 11, Inst Astrophys Spatiale, CNRS, F-91405 Orsay, France.
[Beaty, David W.; Dobrea, Eldar Noe] CALTECH, Jet Prop Lab, Pasadena, CA USA.
[Bish, David] Indiana Univ, Dept Geol Sci, Bloomington, IN 47405 USA.
[Bishop, Janice L.] NASA, Ames Res Ctr, SETI Inst, Mountain View, CA USA.
[Mustard, John F.; Roach, Leah H.] Brown Univ, Dept Geol Sci, Providence, RI 02912 USA.
[Petit, Sabine] Univ Poitiers, CNRS, HYDRASA, Poitiers, France.
RP Poulet, F (reprint author), Univ Paris 11, Inst Astrophys Spatiale, CNRS, Batiment 121, F-91405 Orsay, France.
EM francois.poulet@ias.u-psud.fr
NR 73
TC 11
Z9 11
U1 2
U2 5
PU MARY ANN LIEBERT, INC
PI NEW ROCHELLE
PA 140 HUGUENOT STREET, 3RD FL, NEW ROCHELLE, NY 10801 USA
SN 1531-1074
EI 1557-8070
J9 ASTROBIOLOGY
JI Astrobiology
PD APR
PY 2009
VL 9
IS 3
BP 257
EP 267
DI 10.1089/ast.2009.0335
PG 11
WC Astronomy & Astrophysics; Biology; Geosciences, Multidisciplinary
SC Astronomy & Astrophysics; Life Sciences & Biomedicine - Other Topics;
Geology
GA 457GC
UT WOS:000266915500001
PM 19400732
ER
PT J
AU Brozovic, M
Jacobson, RA
AF Brozovic, M.
Jacobson, R. A.
TI THE ORBITS OF THE OUTER URANIAN SATELLITES
SO ASTRONOMICAL JOURNAL
LA English
DT Article
DE ephemerides; planets and satellites: general; planets and satellites:
individual (Uranus)
ID IRREGULAR SATELLITES; DISCOVERY; URANUS; ORIGIN; INCLINATION; PLANETS;
CAPTURE
AB We report on the numerically integrated orbits for the nine outer Uranian satellites. The orbits are calculated based on fits to the astrometric observations for the period from 1984 to 2006. The results include the state vectors, post-fit residuals, and mean orbital elements. We also assess the accuracy of the orbital fits and discuss the need for future measurements.
C1 [Brozovic, M.; Jacobson, R. A.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
RP Brozovic, M (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA.
EM marina.brozovic@jpl.nasa.gov
FU Jet Propulsion Laboratory; California Institute of Technology; National
Aeronautics and Space Administration
FX The research described here was carried out at the Jet Propulsion
Laboratory, California Institute of Technology, under contract with the
National Aeronautics and Space Administration. The authors thank all of
the astronomers who contributed with their measurements to this orbital
calculation.
NR 22
TC 5
Z9 5
U1 0
U2 1
PU IOP PUBLISHING LTD
PI BRISTOL
PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND
SN 0004-6256
J9 ASTRON J
JI Astron. J.
PD APR
PY 2009
VL 137
IS 4
BP 3834
EP 3842
DI 10.1088/0004-6256/137/4/3834
PG 9
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 417AF
UT WOS:000264046100010
ER
PT J
AU Mattioda, AL
Ricca, A
Tucker, J
Bauschlicher, CW
Allamandola, LJ
AF Mattioda, A. L.
Ricca, A.
Tucker, J.
Bauschlicher, C. W., Jr.
Allamandola, L. J.
TI FAR-INFRARED SPECTROSCOPY OF NEUTRAL CORONENE, OVALENE, AND DICORONYLENE
SO ASTRONOMICAL JOURNAL
LA English
DT Article
DE astrochemistry; infrared: ISM; ISM: molecules; methods: laboratory;
methods: numerical; techniques: spectroscopic
ID POLYCYCLIC AROMATIC-HYDROCARBONS; PAH MOLECULES; EMISSION BANDS;
SPECTRA; DUST; GAS; IDENTIFICATION; FREQUENCIES; CATIONS; CARBON
AB Here we report the first far-IR (FIR) matrix-isolated spectra of the neutral polycyclic aromatic hydrocarbon (PAH) molecules coronene, ovalene, and dicoronylene. The experimental spectra covered the 650-100 cm(-1) (15.385-100 mu m) range and the theoretical spectra covered the 650-10 cm(-1) (15.385-1000 mu m) range. The experimentally measured values are in excellent agreement with theoretical values. The fundamental differences between the skeletal or drumhead modes of the FIR and the group vibrational modes of the mid-IR are discussed and detailed descriptions of the FIR vibrational modes are given.
C1 [Mattioda, A. L.; Ricca, A.; Bauschlicher, C. W., Jr.; Allamandola, L. J.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA.
[Ricca, A.] Carl Sagan Ctr, SETI Inst, Mountain View, CA 94043 USA.
[Tucker, J.] Amherst Coll, Amherst, MA 01002 USA.
RP Mattioda, AL (reprint author), NASA, Ames Res Ctr, Moffett Field, CA 94035 USA.
EM Andrew.L.Mattioda@nasa.gov; Alessandra.Ricca-1@nasa.gov;
Charles.W.Bauschlicher@nasa.gov; Louis.J.Allamandola@nasa.gov
FU NASA's Astronomy and Physics Research and Analysis (APRA) [NNX07AH02G];
Astrobiology [811073]; Spitzer Archival; Herschel Laboratory
Astrophysics Programs; SETI Institute Summer Research Experience for
Undergraduates [AST-0552751]
FX We acknowledge financial support from NASA's Astronomy and Physics
Research and Analysis (APRA) (NNX07AH02G), Astrobiology (811073),
Spitzer Archival, and Herschel Laboratory Astrophysics Programs.
Jonathan Tucker acknowledges the support of the SETI Institute Summer
Research Experience for Undergraduates (funded by NSF award
AST-0552751). We are deeply indebted to Robert Walker for his
outstanding technical support of all phases of the experimental work.
NR 30
TC 28
Z9 28
U1 0
U2 14
PU IOP PUBLISHING LTD
PI BRISTOL
PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND
SN 0004-6256
J9 ASTRON J
JI Astron. J.
PD APR
PY 2009
VL 137
IS 4
BP 4054
EP 4060
DI 10.1088/0004-6256/137/4/4054
PG 7
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 417AF
UT WOS:000264046100031
ER
PT J
AU Miroshnichenko, AS
Hofmann, KH
Schertl, D
Weigelt, G
Kraus, S
Manset, N
Albert, L
Balega, YY
Klochkova, VG
Rudy, RJ
Lynch, DK
Mazuk, S
Venturini, CC
Russell, RW
Grankin, KN
Puetter, RC
Perry, RB
AF Miroshnichenko, A. S.
Hofmann, K. -H.
Schertl, D.
Weigelt, G.
Kraus, S.
Manset, N.
Albert, L.
Balega, Y. Y.
Klochkova, V. G.
Rudy, R. J.
Lynch, D. K.
Mazuk, S.
Venturini, C. C.
Russell, R. W.
Grankin, K. N.
Puetter, R. C.
Perry, R. B.
TI A new spectroscopic and interferometric study of the young stellar
object V645 Cygni
SO ASTRONOMY & ASTROPHYSICS
LA English
DT Article
DE techniques: spectroscopic; techniques: interferometric; stars:
early-type; stars: winds, outflows; circumstellar matter; stars:
individual: V645 Cyg
ID HERBIG-AE/BE STARS; INFRARED SKY SURVEY; 6.7 GHZ; MOLECULAR OUTFLOW;
METHANOL MASERS; EMISSION; V645-CYGNI; ENVELOPES; ATLAS; DUST
AB Aims. We present the results of high-resolution optical spectroscopy, low-resolution near-IR spectroscopy and near-infrared speckle interferometry of the massive young stellar object candidate V645 Cyg, acquired to refine its fundamental parameters and the properties of its circumstellar envelope.
Methods. Speckle interferometry in the H- and K-bands and an optical spectrum in the range 5200-6680 angstrom with a spectral resolving power of R = 60 000 were obtained at the 6 m telescope of the Russian Academy of Sciences. Another optical spectrum in the range 4300-10 500 angstrom with R = 79 000 was obtained at the 3.6 m CFHT. Low-resolution spectra in the ranges 0.46-1.4 mu m and 1.4-2.5 mu m with R similar to 800 and similar to 700, respectively, were obtained at the 3 m Shane telescope of the Lick Observatory.
Results. Using a novel kinematical method based on the non-linear modeling of the neutral hydrogen density profile in the direction toward the object, we propose a distance of D = 4.2 +/- 0.2 kpc. We also suggest a revised estimate of the star's effective temperature, T-eff similar to 25 000 K. We resolved the object in both H- and K-bands. Using a two-component ring fit, we derived a compact component size of 14 mas and 12 mas in the H- and K-band, respectively, which correspond to 29 and 26 AU at the revised distance. Analysis of our own and previously published data indicates a similar to 2 mag decrease in the near-infrared brightness of V645 Cyg at the beginning of the 1980's. At the same time, the cometary nebular condensation N1 appears to fade in this wavelength range with respect to the N0 object, representing the star with a nearly pole-on optically-thick disk and an optically-thin envelope.
Conclusions. We conclude that V645 Cyg is a young, massive, main-sequence star, which recently emerged from its cocoon and has already experienced its protostellar accretion stage. The presence of accretion is not necessary to account for the high observed luminosity of (2-6) x 10(4) M-circle dot yr(-1). The receding part of a strong, mostly uniform outflow with a terminal velocity of similar to 800 km s(-1) is only blocked from view far from the star, where forbidden lines form. The near-infrared size of the source is consistent with the dust sublimation distance close to this hot and luminous star and is the largest among all young stellar objects observed interferometrically to-date.
C1 [Miroshnichenko, A. S.; Hofmann, K. -H.; Schertl, D.; Weigelt, G.; Kraus, S.] Max Planck Inst Radioastron, D-53121 Bonn, Germany.
[Miroshnichenko, A. S.] Univ N Carolina, Dept Phys & Astron, Greensboro, NC 27402 USA.
[Manset, N.; Albert, L.] Canada France Hawaii Telescope Corp, Kamuela, HI 96743 USA.
[Balega, Y. Y.; Klochkova, V. G.] Russian Acad Sci, Special Astrophys Observ, Nizhnyj Arkhyz 369167, Russia.
[Rudy, R. J.; Lynch, D. K.; Mazuk, S.; Venturini, C. C.; Russell, R. W.] Aerosp Corp, Los Angeles, CA 90009 USA.
[Grankin, K. N.] Crimean Astrophys Observ, UA-334413 Nauchnyi, Ukraine.
[Puetter, R. C.] Univ Calif San Diego, Ctr Astrophys & Space Sci, La Jolla, CA 92093 USA.
[Perry, R. B.] NASA, Langley Res Ctr, Earth & Space Sci Support Off, Hampton, VA 23665 USA.
RP Miroshnichenko, AS (reprint author), Max Planck Inst Radioastron, Hugel 69, D-53121 Bonn, Germany.
EM a_mirosh@uncg.edu
OI Grankin, Konstantin/0000-0001-5707-8448
NR 58
TC 4
Z9 5
U1 0
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
EI 1432-0746
J9 ASTRON ASTROPHYS
JI Astron. Astrophys.
PD APR
PY 2009
VL 498
IS 1
BP 115
EP 126
DI 10.1051/0004-6361/200810936
PG 12
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 440DL
UT WOS:000265679500014
ER
PT J
AU van Kempen, TA
van Dishoeck, EF
Salter, DM
Hogerheijde, MR
Jorgensen, JK
Boogert, ACA
AF van Kempen, T. A.
van Dishoeck, E. F.
Salter, D. M.
Hogerheijde, M. R.
Jorgensen, J. K.
Boogert, A. C. A.
TI The nature of the Class I population in Ophiuchus as revealed through
gas and dust mapping
SO ASTRONOMY & ASTROPHYSICS
LA English
DT Article
DE astrochemistry; circumstellar matter; stars: formation; submillimeter;
ISM: clouds; ISM: molecules
ID YOUNG STELLAR OBJECTS; LOW-MASS PROTOSTARS; SPECTRAL
ENERGY-DISTRIBUTIONS; STAR-FORMING REGIONS; SUBMILLIMETER CONTINUUM
OBSERVATIONS; 2-DIMENSIONAL RADIATIVE-TRANSFER; RHO-OPHIUCHI;
PROTOSTELLAR ENVELOPES; DARK CLOUD; MOLECULAR CLOUD
AB Context. The Ophiuchus clouds, in particular L 1688, are an excellent region to study the embedded phases of star formation, due to the relatively large number of protostars. However, the standard method of finding and characterizing embedded young stellar objects (YSOs) through just their infrared spectral slope does not yield a reliable sample. This may affect the age determinations, often derived from the statistics on the total number of embedded YSOs and pre-main sequence stars within a cloud.
Aims. Our aim is to characterize the structure of protostellar envelopes on an individual basis and to correctly identify the embedded YSO population of L 1688.
Methods. Spectral maps of the HCO(+) J = 4-3 and C(18)O J = 3-2 lines, using the HARP-B array on the James Clerk Maxwell Telescope and SCUBA 850 mu m dust maps, are obtained of all sources in the L 1688 region with infrared spectral slopes consistent with, or close to, that of embedded YSOs. Selected 350 mu m maps obtained with the Caltech Submillimeter Observatory are presented as well. The properties, extent and variation of dense gas, column density and dust up to 1' (similar to 7500 AU) are probed at 15 '' resolution. Using the spatial variation of the gas and dust, together with the intensity of the HCO(+) J = 4-3 line, we are able to accurately identify the truly embedded YSOs and determine their properties.
Results. The protostellar envelopes range from 0.05 to 0.5 M(circle dot) in mass. The concentration of HCO(+) emission (similar to 0.5 to 0.9) is generally higher than that of the dust concentration. Combined with absolute intensities, HCO(+) proves to be a better tracer of protostellar envelopes than dust, which can contain disk and cloud contributions. Our total sample of 45 sources, including all previously classified Class I sources, several flat-spectrum sources and some known disks, was re-classified using the molecular emission. Of these, only 17 sources are definitely embedded YSOs. Four of these embedded YSOs have little (0.1-0.2 M(circle dot)) envelope material remaining and are likely at the interesting transitional stage from embedded YSO to T Tauri star. About half of the flat-spectrum sources are found to be embedded YSOs and about half are disks.
Conclusions. The presented classification method is successful in separating embedded YSOs from edge-on disks and confused sources. The total embedded population of the Ophiuchus L 1688 cloud is found almost exclusively in Oph-A, Oph-B2 and the Ophiuchus ridge with only three embedded YSOs not related to these regions. The detailed characterization presented will be necessary to interpret deep interferometric ALMA and future Herschel observations.
C1 [van Kempen, T. A.; van Dishoeck, E. F.; Salter, D. M.; Hogerheijde, M. R.] Leiden Univ, Leiden Observ, NL-2300 RA Leiden, Netherlands.
[van Kempen, T. A.] Ctr Astrophys, Cambridge, MA 02138 USA.
[van Dishoeck, E. F.] Max Planck Inst Extraterr Phys, MPE, D-85748 Garching, Germany.
[Jorgensen, J. K.] Univ Bonn, Argelander Inst Astron, D-53121 Bonn, Germany.
[Boogert, A. C. A.] NASA, Herschel Sci Ctr, Infrared Proc & Anal Ctr IPAC, Pasadena, CA 91125 USA.
RP van Kempen, TA (reprint author), Leiden Univ, Leiden Observ, POB 9513, NL-2300 RA Leiden, Netherlands.
EM tvankempen@cfa.harvard.edu
RI Jorgensen, Jes Kristian/L-7936-2014
OI Jorgensen, Jes Kristian/0000-0001-9133-8047
NR 82
TC 50
Z9 50
U1 0
U2 0
PU EDP SCIENCES S A
PI LES ULIS CEDEX A
PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A,
FRANCE
SN 0004-6361
J9 ASTRON ASTROPHYS
JI Astron. Astrophys.
PD APR
PY 2009
VL 498
IS 1
BP 167
EP 194
DI 10.1051/0004-6361/200810445
PG 28
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 440DL
UT WOS:000265679500019
ER
PT J
AU Stute, M
Sahai, R
AF Stute, M.
Sahai, R.
TI Detection of X-rays from the jet-driving symbiotic star MWC 560
SO ASTRONOMY & ASTROPHYSICS
LA English
DT Article
DE accretion, accretion disks; binaries: symbiotic; stars: individual: MWC
560 (V694 Mon); stars: white dwarfs; X-rays: stars
ID PHOTON IMAGING CAMERA; SYSTEM CH-CYGNI; R-AQUARII; HYDRODYNAMICAL
SIMULATIONS; XMM-NEWTON; CATACLYSMIC VARIABLES; EMISSION; MWC-560;
SPECTRUM; RADIATION
AB Aims. We report the detection of X-ray emission from the jet-driving symbiotic star MWC 560.
Methods. We observed MWC 560 with XMM-Newton for 36 ks. We fitted the spectra from the EPIC pn, MOS1 and MOS2 instruments with XSPEC and examined the light curves with the package XRONOS.
Results. The spectrum can be fitted with a highly absorbed hard X-ray component from an optically thin hot plasma, a Gaussian emission line with an energy of 6.1 keV and a less absorbed soft thermal component. The best fit is obtained with a model in which the hot component is produced by optically thin thermal emission from an isobaric cooling flow with a maximum temperature of 61 keV, which might be created inside an optically thin boundary layer on the surface of the accreting with dwarf. The derived parameters of the hard component detected from MWC 560 are in good agreement with similar objects such as CH Cyg, SS7317, RT Cru and T CrB, which all form a new sub-class of symbiotic stars emitting hard X-rays. Our previous numerical simulations of the jet of MWC 560 showed that it should produce detectable soft X-ray emission. We infer a temperature of 0.17 keV for the observed soft component, i.e. less than expected from our models. The total soft X-ray flux (i.e. at <3 keV) is more than a factor 100 less than predicted for the propagating jet soon after its birth (<0.3 yr), but consistent with the value expected due its decrease with age. The ROSAT upper limit is also consistent with such a decrease. We find aperiodic or quasi-periodic variability on timescales of minutes and hours, but no periodic rapid variability.
Conclusions. All results are consistent with an accreting white dwarf powering the X-ray emission and the existence of an optically thin boundary layer around it.
C1 [Stute, M.] Univ Athens, Dept Phys, IASA, Athens 15784, Greece.
[Stute, M.] Univ Athens, Sect Astrophys Astron & Mech, Dept Phys, Athens 15784, Greece.
[Sahai, R.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
RP Stute, M (reprint author), Univ Athens, Dept Phys, IASA, Athens 15784, Greece.
EM mstute@phys.uoa.gr
NR 52
TC 9
Z9 9
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 APR
PY 2009
VL 498
IS 1
BP 209
EP 215
DI 10.1051/0004-6361/200811176
PG 7
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 440DL
UT WOS:000265679500021
ER
PT J
AU Roccatagliata, V
Henning, T
Wolf, S
Rodmann, J
Corder, S
Carpenter, JM
Meyer, MR
Dowell, D
AF Roccatagliata, V.
Henning, Th.
Wolf, S.
Rodmann, J.
Corder, S.
Carpenter, J. M.
Meyer, M. R.
Dowell, D.
TI Long-wavelength observations of debris discs around sun-like stars
SO ASTRONOMY & ASTROPHYSICS
LA English
DT Review
DE circumstellar matter; planetary systems: formation; stars: late-type;
Kuiper Belt
ID SCORPIUS OB ASSOCIATION; MAIN-SEQUENCE STARS; TERRESTRIAL PLANET
FORMATION; NEARBY YOUNG STARS; SOLAR-TYPE STARS; T-TAURI STARS;
CIRCUMSTELLAR DISKS; DUSTY DEBRIS; UPPER LIMITS; COLLISIONAL CASCADES
AB Context. Tracing the evolution of debris discs is essential for our understanding of the architecture of planetary system. Even though the evolution of their inner discs has been recently studied with the Spitzer Space Telescope at mid- to far-infrared wavelengths, the outer discs are best characterised by sensitive millimetre observations.
Aims. The goal of our study is to understand the evolution timescale of circumstellar debris discs, and the physical mechanisms responsible for such evolution around solar-type stars. In addition, we make a detailed characterisation of the detected debris discs.
Methods. Two deep surveys of circumstellar discs around solar-type stars at different ages were carried out at 350 mu m with the CSO and at 1.2 mm with the IRAM 30-m telescope. The dust disc masses were computed from the millimetre emission, where the discs are optically thin. Theoretically, the mass of the disc is expected to decrease with time. To test this hypothesis, we performed the generalised Kendall's tau correlation and three different two-sample tests. A characterisation of the detected debris discs has been obtained by computing the collision and Poynting-Robertson timescales and by modelling the spectral energy distribution.
Results. The Kendall's tau correlation yields a probability of 76% that the mass of debris discs and their age are correlated. Similarly, the three two-sample tests give a probability between 70 and 83% that younger and older debris systems belong to different parent populations in terms of dust mass. We detected submillimetre/millimetre emission from six debris discs, enabling a detailed SED modelling. Conclusions. Our results on the correlation and evolution of dust mass as a function of age are conditioned by the sensitivity limit of our survey. Deeper millimetre observations are needed to confirm the evolution of debris material around solar-like stars. In the case of the detected discs, the comparison between collision and Poynting-Robertson timescales supports the hypothesis that these discs are dominated by collisions. All detected debris disc systems show the inner part evacuated from small micron-sized grains.
C1 [Roccatagliata, V.; Henning, Th.; Wolf, S.] MPIA, D-69117 Heidelberg, Germany.
[Wolf, S.] Univ Kiel, Inst Theoret Phys & Astrophys, D-24098 Kiel, Germany.
[Rodmann, J.] Estec, ESA, Res & Sci Support Dept, NL-2201 AZ Noordwijk, Netherlands.
[Corder, S.; Carpenter, J. M.] CALTECH, Dept Astron, Pasadena, CA 91125 USA.
[Meyer, M. R.] Univ Arizona, Steward Observ, Tucson, AZ 85721 USA.
[Dowell, D.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
RP Roccatagliata, V (reprint author), MPIA, Konigstuhl 17, D-69117 Heidelberg, Germany.
EM roccata@mpia.de
RI Roccatagliata, Veronica/Q-3421-2016
FU German Research Foundation (DFG) through the Emmy Noether [WO 857/2];
NASA Astrobiology Institute; National Science Foundation [AST-0540882]
FX All the authors wish to thank the entire FEPS team for their work. V. R.
thanks A. Sicilia-Aguilar for helpful discussions on the IRAM data
reduction, E. Feigelson for his suggestions about the survival analysis,
L. Hillenbrand for some details about the stellar ages, S. J. Kim for
her suggestions about the FEPS sample, A. Pasquali and A.
Martinez-Sansigre for reading the manuscript. S. W. was supported at the
MPIA by the German Research Foundation (DFG) through the Emmy Noether
grant WO 857/2. J. R. wishes to thank Jesus Falcon-Barroso for a helpful
discussion on how to project 3-d isosurfaces to lower dimensions. M. R.
M. thanks support provided through the LAPLACE node of the NASA
Astrobiology Institute. Research at the Caltech Submillimetre
Observatory is supported by grant AST-0540882 from the National Science
Foundation.
NR 101
TC 38
Z9 38
U1 2
U2 5
PU EDP SCIENCES S A
PI LES ULIS CEDEX A
PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A,
FRANCE
SN 0004-6361
J9 ASTRON ASTROPHYS
JI Astron. Astrophys.
PD APR
PY 2009
VL 497
IS 2
BP 409
EP 421
DI 10.1051/0004-6361/200811018
PG 13
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 431XE
UT WOS:000265097300011
ER
PT J
AU Ferrero, P
Klose, S
Kann, DA
Savaglio, S
Schulze, S
Palazzi, E
Maiorano, E
Bohm, P
Grupe, D
Oates, SR
Sanchez, SF
Amati, L
Greiner, J
Hjorth, J
Malesani, D
Barthelmy, SD
Gorosabel, J
Masetti, N
Roth, MM
AF Ferrero, P.
Klose, S.
Kann, D. A.
Savaglio, S.
Schulze, S.
Palazzi, E.
Maiorano, E.
Boehm, P.
Grupe, D.
Oates, S. R.
Sanchez, S. F.
Amati, L.
Greiner, J.
Hjorth, J.
Malesani, D.
Barthelmy, S. D.
Gorosabel, J.
Masetti, N.
Roth, M. M.
TI GRB 060605: multi-wavelength analysis of the first GRB observed using
integral field spectroscopy
SO ASTRONOMY & ASTROPHYSICS
LA English
DT Article
DE gamma rays: bursts
ID GAMMA-RAY BURSTS; AFTERGLOW LIGHT CURVES; SWIFT XRT DATA; POTSDAM
MULTIAPERTURE SPECTROPHOTOMETER; X-RAY; OPTICAL AFTERGLOW; COMPREHENSIVE
ANALYSIS; COLUMN DENSITY; TELESCOPE; PROGENITOR
AB The long and relatively faint gamma-ray burst GRB 060605 detected by Swift/BAT lasted about 20 s. Its afterglow could be observed with Swift/XRT for nearly 1 day, while Swift/UVOT could detect the afterglow during the first 6 h after the event. Here, we report on integral field spectroscopy of its afterglow performed with PMAS/PPak mounted at the Calar Alto 3.5 m telescope. In addition, we report on a detailed analysis of XRT and UVOT data and on the results of deep late-time VLT observations that reveal the GRB host galaxy. We find that the burst occurred at a redshift of z = 3.773, possibly associated with a faint, RC = 26.4 +/- 0.3 host. Based on the optical and X-ray data, we deduce information on the SED of the afterglow, the position of the cooling frequency in the SED, the nature of the circumburst environment, its collimation factor, and its energetics. We find that the GRB fireball was expanding into a constant-density medium and that the explosion was collimated with a narrow half-opening angle of about 2.4 degrees. The initial Lorentz factor of the fireball was about 250; however, its beaming-corrected energy release in the gamma-ray band was comparably low. The optical, X-ray afterglow, on the other hand, was rather luminous. Finally, we find that the data are consistent within the error bars with an achromatic evolution of the afterglow during the suspected jet break time at about 0.27 days after the burst.
C1 [Ferrero, P.; Klose, S.; Kann, D. A.; Schulze, S.] Thuringer Landessternwarte Tautenburg, D-07778 Tautenburg, Germany.
[Savaglio, S.; Greiner, J.] Max Planck Inst Extraterr Phys, D-85748 Garching, Germany.
[Palazzi, E.; Maiorano, E.; Amati, L.; Masetti, N.] INAF Ist Astrofis Spaziale & Fis Cosm Bologna, I-40129 Bologna, Italy.
[Maiorano, E.] Univ Ferrara, Dipartimento Fis, I-44100 Ferrara, Italy.
[Boehm, P.; Roth, M. M.] Inst Astrophys, D-14482 Potsdam, Germany.
[Grupe, D.] Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA.
[Oates, S. R.] Univ Coll London, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England.
[Sanchez, S. F.] Ctr Astron Hispano Aleman Calar Alto, Almeria 04004, Spain.
[Hjorth, J.; Malesani, D.] Univ Copenhagen, Dark Cosmol Ctr, Niels Bohr Inst, DK-2100 Copenhagen, Denmark.
[Barthelmy, S. D.] NASA, Goddard Space Flight Ctr, Astroparticle Phys Lab, Greenbelt, MD 20771 USA.
[Gorosabel, J.] IAA CSIC, Inst Astrofis Andalucia, Granada 18080, Spain.
RP Ferrero, P (reprint author), Thuringer Landessternwarte Tautenburg, Sternwarte 5, D-07778 Tautenburg, Germany.
EM ferrero@tls-tautenburg.de
RI Barthelmy, Scott/D-2943-2012; Hjorth, Jens/M-5787-2014; Palazzi,
Eliana/N-4746-2015; Amati, Lorenzo/N-5586-2015;
OI Schulze, Steve/0000-0001-6797-1889; Hjorth, Jens/0000-0002-4571-2306;
Masetti, Nicola/0000-0001-9487-7740; Savaglio,
Sandra/0000-0003-2354-3238; Amati, Lorenzo/0000-0001-5355-7388; Palazzi,
Eliana/0000-0002-8691-7666
FU DFG [Kl 766/13-2]; German Academic Exchange Service (DAAD) [D/05/54048];
Spanish Ministry of Science and Education [AYA2004-01515,
ESP2005-07714-C03-03]; NASA [NAS5-00136]; Danish National Research
Foundation; ESO staff
FX P. F., S. K. and D. A. K., acknowledge financial support by DFG grant Kl
766/13-2 and by the German Academic Exchange Service (DAAD) under grant
No. D/05/54048. S. K. and S. S. thank Kim Page (Leicester) for useful
discussions. The research activities of J. G. are supported by the
Spanish Ministry of Science and Education through projects AYA2004-01515
and ESP2005-07714-C03-03. Swift is supported at PSU by NASA contract
NAS5-00136. The Dark Cosmology Centre is funded by the Danish National
Research Foundation. We thank the Calar Alto and the ESO staff for
excellent support and the referee for a very careful reading of the
manuscript and very helpful remarks.
NR 81
TC 28
Z9 28
U1 0
U2 1
PU EDP SCIENCES S A
PI LES ULIS CEDEX A
PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A,
FRANCE
SN 0004-6361
J9 ASTRON ASTROPHYS
JI Astron. Astrophys.
PD APR
PY 2009
VL 497
IS 3
BP 729
EP 741
DI 10.1051/0004-6361/200809980
PG 13
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 434ND
UT WOS:000265280500009
ER
PT J
AU van Peet, JCA
Costantini, E
Mendez, M
Paerels, FBS
Cottam, J
AF van Peet, J. C. A.
Costantini, E.
Mendez, M.
Paerels, F. B. S.
Cottam, J.
TI Properties of the ionised plasma in the vicinity of the neutron-star
X-ray binary EXO 0748-676
SO ASTRONOMY & ASTROPHYSICS
LA English
DT Article
DE atomic processes; stars: binaries: general; X-rays: binaries; X-rays:
individuals: EXO 0748-676
ID PHOTON IMAGING CAMERA; XMM-NEWTON; PHOTOIONIZED PLASMA; CIRCUMBINARY
DISKS; ECLIPSE TIMINGS; ACCRETION DISK; LIGHT CURVES; EXO-0748-676;
DISCOVERY; BURST
AB Aims. We present the spectral analysis of a large set of XMM-Newton observations of EXO 0748-676, a bright dipping low-mass X-ray binary. In particular, we focus on the dipping phenomenon as a result of changes in the properties of the ionised gas close to the source.
Methods. We analysed the high-resolution spectra collected with the reflection grating spectrometer on board XMM-Newton. We studied dipping and persistent spectra separately. We used the Epic data to constrain the broad-band continuum. We explored two simple geometrical scenarios for which we derived physical quantities of the absorbing material like the density, size, and mass.
Results. We find that the continuum is absorbed by a neutral gas, and by both a collisionally (temperature T similar to 70 eV) and photoionised (ionisation parameter log xi similar to 2.5) absorbers. Emission lines from OVII and OVIII are also detected. This is the first time that evidence of a collisionally ionised absorber has been found in a low-mass X-ray binary. The collisionally ionised absorber may be in the form of dense (n > 10(14) cm(-3)) filaments, located at a distance r greater than or similar to 10(11) cm. During dips, the photoionised absorber significantly increases its column density (factor 2-4) while becoming less ionised. This strengthens the idea that the colder material of the accretion stream impinging the disc is passing on our line of sight during dips. In this scenario, we find that the distance from the neutron star to the impact region (similar to 5 x 10(10) cm) is similar to the size of the neutron star's Roche lobe. The gas observed during the persistent state may have a flattened geometry. Finally, we explore the possibility of the existence of material forming an initial, hotter portion of a circumbinary disc.
C1 [van Peet, J. C. A.; Costantini, E.] Netherlands Inst Space Res, SRON, NL-3584 CA Utrecht, Netherlands.
[Mendez, M.] Univ Groningen, Kapteyn Astron Inst, NL-9700 AV Groningen, Netherlands.
[Paerels, F. B. S.] Columbia Univ, Dept Astron, Columbia Astrophys Lab, New York, NY 10027 USA.
[Cottam, J.] NASA, Goddard Space Flight Ctr, Explorat Universe Div, Greenbelt, MD 20771 USA.
RP van Peet, JCA (reprint author), Netherlands Inst Space Res, SRON, Sorbonnelaan 2, NL-3584 CA Utrecht, Netherlands.
EM e.costantini@sron.nl
RI Mendez, Mariano/C-8011-2012
OI Mendez, Mariano/0000-0003-2187-2708
FU NWO, The Netherlands Organisation for Scientific Research
FX The authors wish to thank the anonymous referee for his/her useful
comments. The Space Research Organisation of the Netherlands is
financially supported by NWO, The Netherlands Organisation for
Scientific Research.
NR 35
TC 10
Z9 10
U1 0
U2 0
PU EDP SCIENCES S A
PI LES ULIS CEDEX A
PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A,
FRANCE
SN 0004-6361
J9 ASTRON ASTROPHYS
JI Astron. Astrophys.
PD APR
PY 2009
VL 497
IS 3
BP 805
EP 813
DI 10.1051/0004-6361/200811181
PG 9
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 434ND
UT WOS:000265280500014
ER
PT J
AU Ibarra, A
Kuulkers, E
Osborne, JP
Page, K
Ness, JU
Saxton, RD
Baumgartner, W
Beckmann, V
Bode, MF
Hernanz, M
Mukai, K
Orio, M
Sala, G
Starrfield, S
Wynn, GA
AF Ibarra, A.
Kuulkers, E.
Osborne, J. P.
Page, K.
Ness, J. U.
Saxton, R. D.
Baumgartner, W.
Beckmann, V.
Bode, M. F.
Hernanz, M.
Mukai, K.
Orio, M.
Sala, G.
Starrfield, S.
Wynn, G. A.
TI Pre-nova X-ray observations of V2491 Cygni (Nova Cyg 2008b)
SO ASTRONOMY & ASTROPHYSICS
LA English
DT Article
DE X-rays: binaries; novae, cataclysmic variables
ID CATACLYSMIC VARIABLES; AM-HERCULIS; EMISSION; ROSAT; INTEGRAL/IBIS;
TELESCOPE; BAT
AB Classical novae are phenomena caused by explosive hydrogen burning onto an accreting white dwarf. Only one classical nova had been identified in X-rays before the actual optical outburst occurred (V2487 Oph). The recently discovered nova, V2491 Cyg, is one of the fastest (He/N) novae observed to date. Using archival ROSAT, XMM-Newton, and Swift data, we show that V2491 Cyg was a persistent X-ray source during its quiescent time before the optical outburst. We present the X-ray spectral characteristics and derive X-ray fluxes. The pre-outburst X-ray emission is variable, and, at least in one observation, it exhibits a soft X-ray source.
C1 [Ibarra, A.; Kuulkers, E.; Ness, J. U.; Saxton, R. D.] ESAC, ESA, Madrid 28691, Spain.
[Osborne, J. P.; Page, K.; Wynn, G. A.] Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England.
[Baumgartner, W.] Univ Maryland Baltimore Cty, Baltimore, MD 21250 USA.
[Beckmann, V.] ISDC Data Ctr Astrophys, CH-1290 Versoix, Switzerland.
[Beckmann, V.] Univ Geneva, Astron Observ, CH-1290 Sauverny, Switzerland.
[Bode, M. F.] Liverpool John Moores Univ, Astroph Res Inst, Birkenhead CH41 1LD7, Merseyside, England.
[Hernanz, M.] CSIC, IEEC, Fac Ciencies, Bellaterra 08193, Spain.
[Mukai, K.] NASA, Goddard Space Flight Ctr, CRESST, Greenbelt, MD 20771 USA.
[Mukai, K.] NASA, Goddard Space Flight Ctr, Xray Astrophys Lab, Greenbelt, MD 20771 USA.
[Orio, M.] Osserv Astron Padova, INAF, I-35122 Padua, Italy.
[Orio, M.] Univ Wisconsin, Dept Astron, Madison, WI 53706 USA.
[Sala, G.] Univ Politecn Cataluna, Dept Fis & Engn Nucl, Grp Astron & Astrofis, Barcelona 08036, Spain.
[Starrfield, S.] Arizona State Univ, Sch Earth & Space Explorat, Tempe, AZ 85287 USA.
EM Aitor.Ibarra@sciops.esa.int
RI Hernanz, Margarita/K-1770-2014
OI Hernanz, Margarita/0000-0002-8651-7910
FU XMM-Newton; ESA Member States; USA (NASA); STFC; NSF
FX We acknowledge the use of observations obtained with XMM-Newton, an ESA
science mission with instrument and contributions directly funded by ESA
Member States and the USA (NASA), as well as public data from the Swift
data archive. J. O. and K. P. acknowledge the support of the STFC; S. S.
acknowledges partial support from NASA and NSF grants to ASU.
NR 47
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 1432-0746
J9 ASTRON ASTROPHYS
JI Astron. Astrophys.
PD APR
PY 2009
VL 497
IS 1
BP L5
EP L8
DI 10.1051/0004-6361/200911710
PG 4
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 429AG
UT WOS:000264892600002
ER
PT J
AU Turyshev, VG
AF Turyshev, V. G.
TI Relativistic gravitational deflection of light and its impact on the
modeling accuracy for the Space Interferometry Mission
SO ASTRONOMY LETTERS-A JOURNAL OF ASTRONOMY AND SPACE ASTROPHYSICS
LA English
DT Article
DE Interferometric astrometry; SIM; tests of general relativity; solar
system
ID POST-NEWTONIAN FORMALISM; GENERAL-RELATIVITY; 2ND-ORDER CONTRIBUTIONS;
REFERENCE FRAME; TIME-DELAY; ASTROMETRY; GAIA; JUPITER; MASSES; GALAXY
AB We study the impact of relativistic gravitational deflection of light on the accuracy of future Space Interferometry Mission (SIM). We estimate the deflection angles caused by the monopole, quadrupole and octupole components of gravitational fields for a number of celestial bodies in the solar system. We observe that, in many cases, the magnitude of the corresponding effects is significantly larger than the 1 A mu as accuracy expected from SIM. This fact argues for the development of a relativistic observational model for the mission that would account for the influence of both static and time-varying effects of gravity on light propagation. Results presented here are different from the ones obtained elsewhere by the fact that we specifically account for the differential nature of the future SIM astrometric measurements. We also obtain an estimate for the accuracy of possible determination of the Eddington's parameter gamma via SIM global astrometric campaign; we conclude that accuracy of similar to 7 x 10(-6) is achievable via measurements of deflection of light by solar gravity.
C1 [Turyshev, V. G.] Moscow MV Lomonosov State Univ, Sternberg Astron Inst, Moscow 119992, Russia.
[Turyshev, V. G.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
RP Turyshev, VG (reprint author), Moscow MV Lomonosov State Univ, Sternberg Astron Inst, 13 Univ Pr, Moscow 119992, Russia.
EM turyshev@sai.msu.ru
NR 57
TC 5
Z9 5
U1 2
U2 3
PU MAIK NAUKA/INTERPERIODICA/SPRINGER
PI NEW YORK
PA 233 SPRING ST, NEW YORK, NY 10013-1578 USA
SN 1063-7737
EI 1562-6873
J9 ASTRON LETT+
JI Astron. Lett.-J. Astron. Space Astrophys.
PD APR
PY 2009
VL 35
IS 4
BP 215
EP 234
DI 10.1134/S106377370904001X
PG 20
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 429LV
UT WOS:000264922800001
ER
PT J
AU Scully, ST
Stecker, FW
AF Scully, S. T.
Stecker, F. W.
TI Lorentz invariance violation and the observed spectrum of ultrahigh
energy cosmic rays
SO ASTROPARTICLE PHYSICS
LA English
DT Article
DE Cosmic rays; Lorentz invariance; Quantum gravity
ID QUANTUM-GRAVITY; UNIVERSE; TESTS
AB There has been much interest in possible violations of Lorentz invariance, particularly motivated by quantum gravity theories. It has been suggested that a small amount of Lorentz invariance violation (LIV) could turn off photomeson interactions of ultrahigh energy cosmic rays (UHECRs) with photons of the cosmic background radiation and thereby eliminate the resulting sharp steepening in the spectrum of the highest energy CRs predicted by Greisen Zatsepin and Kuzmin (GZK). Recent measurements of the UHECR spectrum reported by the HiRes and Auger collaborations, however, indicate the presence of the GZK effect. We present the results of a detailed calculation of the modification of the UHECR spectrum caused by LIV using the formalism of Coleman and Glashow. We then compare these results with the experimental UHECR data from Auger and HiRes. Based on these data, we find a best-fit amount of LIV of 4.5(-4.5)(+1.5) X 10(-23), 10(-23) consistent with an upper limit of 6 x 10(-23). This possible amount of LIV can lead to a recovery of the cosmic ray spectrum at higher energies than presently observed. Such an LIV recovery effect can be tested observationally using future detectors. (C) 2009 Elsevier B.V. All rights reserved.
C1 [Stecker, F. W.] NASA, Goddard Space Flight Ctr, Astrophys Sci Div, Greenbelt, MD 20771 USA.
[Scully, S. T.] James Madison Univ, Dept Phys & Astron, Harrisonburg, VA 22807 USA.
RP Stecker, FW (reprint author), NASA, Goddard Space Flight Ctr, Astrophys Sci Div, Greenbelt, MD 20771 USA.
EM stecker@lheapop.gsfc.nasa.gov
RI Stecker, Floyd/D-3169-2012
FU Thomas F. and Kate Miller Jeffress Memorial Trust [J-805]
FX STS gratefully acknowledges partial support from the Thomas F. and Kate
Miller Jeffress Memorial Trust Grant No. J-805.
NR 38
TC 26
Z9 26
U1 0
U2 1
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0927-6505
EI 1873-2852
J9 ASTROPART PHYS
JI Astropart Phys.
PD APR
PY 2009
VL 31
IS 3
BP 220
EP 225
DI 10.1016/j.astropartphys.2009.01.002
PG 6
WC Astronomy & Astrophysics; Physics, Particles & Fields
SC Astronomy & Astrophysics; Physics
GA 435HK
UT WOS:000265334500007
ER
PT J
AU Collins, NR
Kraemer, SB
Crenshaw, DM
Bruhweiler, FC
Melendez, M
AF Collins, N. R.
Kraemer, S. B.
Crenshaw, D. M.
Bruhweiler, F. C.
Melendez, M.
TI PHYSICAL CONDITIONS IN THE NARROW-LINE REGION OF MARKARIAN 3. II.
PHOTOIONIZATION MODELING RESULTS
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE galaxies: individual (Markarian 3); galaxies: Seyfert; line: formation
ID ACTIVE GALACTIC NUCLEI; SEYFERT-2 GALAXY MARKARIAN-3;
LARGE-MAGELLANIC-CLOUD; SPACE-TELESCOPE; EMISSION-LINE; NGC 4151;
RESOLVED SPECTROSCOPY; ULTRAVIOLET ABSORBERS; INTERSTELLAR GRAINS;
INFRARED-EMISSION
AB We have examined the physical conditions in the narrow-line region (NLR) of the Seyfert 2 galaxy Markarian 3, using long-slit spectra obtained with the Hubble Space Telescope/Space Telescope Imaging Spectrograph, and photoionization models. We find three components of photoionized gas in the NLR. Two of these components, characterized by emission lines such as [Ne v]lambda 3426 and [O III]lambda 5007, lie within the envelope of the biconical region described in our previous kinematic study. A component of lower ionization gas, in which lines such as [O II]lambda 3727 arise, is found to lie outside the bicone. Each of these components is irradiated by a power-law continuum which is attenuated by intervening gas, presumably closer to the central source. The radiation incident upon the low-ionization gas, external to the bicone, is much more heavily absorbed. These absorbers are similar to the intrinsic UV and X-ray absorbers detected in many Seyfert 1 galaxies, which suggests that the collimation of the ionizing radiation occurs in a circumnuclear wind, rather than a thick, molecular torus. We estimate the mass for the observed NLR emitting gas to be 2 x 10(6) M(circle dot). It is likely that Markarian 3 acquired this gas through an ongoing interaction with the spiral galaxy UGC 3422.
C1 [Collins, N. R.; Kraemer, S. B.; Bruhweiler, F. C.] Catholic Univ Amer, Dept Phys, Inst Astrophys & Computat Sci, Washington, DC 20064 USA.
[Collins, N. R.; Kraemer, S. B.; Bruhweiler, F. C.] NASA, Goddard Space Flight Ctr, Astrophys Sci Div, Greenbelt, MD 20771 USA.
[Crenshaw, D. M.] Georgia State Univ, Dept Phys & Astron, Atlanta, GA 30303 USA.
RP Collins, NR (reprint author), Catholic Univ Amer, Dept Phys, Inst Astrophys & Computat Sci, Washington, DC 20064 USA.
EM nicholas.collins@nasa.gov; steven.b.kraemer@nasa.gov;
frederick.c.bruhweiler@nasa.gov; marcio@milkyway.gsfc.nasa.gov
FU NASA [NAS-526555, NAG5-7584]; [NAG5-4103]; [NAG5-13109]
FX We acknowledge the financial support of NAG5-4103 and NAG5-13109.
NR 47
TC 12
Z9 12
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 APR 1
PY 2009
VL 694
IS 2
BP 765
EP 788
DI 10.1088/0004-637X/694/2/765
PG 24
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 424AW
UT WOS:000264538900005
ER
PT J
AU Marshall, PJ
Hogg, DW
Moustakas, LA
Fassnacht, CD
Bradac, M
Schrabback, T
Blandford, RD
AF Marshall, Philip J.
Hogg, David W.
Moustakas, Leonidas A.
Fassnacht, Christopher D.
Bradac, Marusa
Schrabback, Tim
Blandford, Roger D.
TI AUTOMATED DETECTION OF GALAXY-SCALE GRAVITATIONAL LENSES IN
HIGH-RESOLUTION IMAGING DATA
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE galaxies: elliptical and lenticular, cD; gravitational lensing; methods:
data analysis; methods: statistical; surveys; techniques: miscellaneous
ID LYMAN BREAK GALAXY; HUBBLE DEEP FIELD; ALL-SKY SURVEY; ACS SURVEY;
CANDIDATE SELECTION; TIME DELAYS; EVOLUTION; SEARCH; QUASAR; SAMPLE
AB We expect direct lens modeling to be the key to successful and meaningful automated strong galaxy-scale gravitational lens detection. We have implemented a lens-modeling "robot" that treats every bright red galaxy (BRG) in a large imaging survey as a potential gravitational lens system. Having optimized a simple model for "typical" galaxy-scale gravitational lenses, we generate four assessments of model quality that are then used in an automated classification. The robot infers from these four data the lens classification parameter H that a human would have assigned; the inference is performed using a probability distribution generated from a human-classified training set of candidates, including realistic simulated lenses and known false positives drawn from the Hubble Space Telescope (HST) Extended Groth Strip (EGS) survey. We compute the expected purity, completeness, and rejection rate, and find that these statistics can be optimized for a particular application by changing the prior probability distribution for H; this is equivalent to defining the robot's "character." Adopting a realistic prior based on expectations for the abundance of lenses, we find that a lens sample may be generated that is similar to 100% pure, but only similar to 20% complete. This shortfall is due primarily to the oversimplicity of the model of both the lens light and mass. With a more optimistic robot, similar to 90% completeness can be achieved while rejecting similar to 90% of the candidate objects. The remaining candidates must be classified by human inspectors. Displaying the images used and produced by the robot on a custom "one-click" web interface, we are able to inspect and classify lens candidates at a rate of a few seconds per system, suggesting that a future 1000 deg(2) imaging survey containing 10(7) BRGs, and some 10(4) lenses, could be successfully, and reproducibly, searched in a modest amount of time. We have verified our projected survey statistics, albeit at low significance, using the HST EGS data, discovering four new lens candidates in the process.
C1 [Marshall, Philip J.; Blandford, Roger D.] Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93601 USA.
[Marshall, Philip J.; Bradac, Marusa; Blandford, Roger D.] Kavli Inst Particle Astrophys & Cosmol, Stanford, CA 94309 USA.
[Hogg, David W.] NYU, Dept Phys, Ctr Cosmol & Particle Phys, New York, NY 10003 USA.
[Moustakas, Leonidas A.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
[Fassnacht, Christopher D.] Univ Calif Davis, Dept Phys, Davis, CA 95616 USA.
[Schrabback, Tim] Univ Bonn, Argelander Inst Astron, D-53121 Bonn, Germany.
[Schrabback, Tim] Leiden Univ, Leiden Observ, NL-2333 CA Leiden, Netherlands.
RP Marshall, PJ (reprint author), Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93601 USA.
EM pjm@physics.ucsb.edu
OI Moustakas, Leonidas/0000-0003-3030-2360; Hogg, David/0000-0003-2866-9403
FU NASA [HST-AR-10676, NAS 5-26555]; Space Telescope Science Institute;
U.S. Department of Energy, at the Stanford Linear Accelerator Center
[DE-AC02-76SF00515]; TABASGO foundation; National Science Foundation;
Netherlands Organization for Scientific Research (NWO); German Ministry
for Science and Education (BMBF)
FX We thank Raphael Gavazzi, Tommaso Treu, Eric Morganson, Elisabeth
Newton, Marco Lombardi, Ole Moller, and Konrad Kuijken for useful
discussions, Jean-Paul Kneib for much encouragement, and Cecile Faure
for a careful reading of the manuscript. We also thank the anonymous
referee for their thoughtful queries and comments. We are grateful to
the EGS team for providing their high level science products at an early
stage in the project. D. W. H. thanks the staff of the Spitzer Science
Center for their hospitality during his visit when some of this work was
carried out. We are very grateful to Stuart Marshall and Glenn Morris at
KIPAC for providing computing support. Support for this work was
provided by NASA through grant HST-AR-10676 (the HAGGLeS project) from
the Space Telescope Science Institute, which is operated by AURA, Inc.,
under NASA contract NAS 5-26555. The work of P.J.M., R. D. B., and M. B.
was supported in part by the U.S. Department of Energy, under contract
DE-AC02-76SF00515 at the Stanford Linear Accelerator Center. P.J.M.
acknowledges support from the TABASGO foundation in the form of a
research fellowship. The work of L. A. M. was carried out at the Jet
Propulsion Laboratory, California Institute of Technology, under a
contract with NASA. The work of R. D. B. was supported in part by a
National Science Foundation grant, "Gravitational optics, dark matter,
and the evolution of faint galaxies," and by a U. S. Department of
Energy Computational Astrophysics Consortium grant, "3. supernovae,
gamma-ray bursts, and nucleosynthesis." T. S. acknowledges financial
support from the Netherlands Organization for Scientific Research (NWO)
and the German Ministry for Science and Education (BMBF) through the
TR33 "The Dark Universe."
NR 63
TC 35
Z9 35
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 APR 1
PY 2009
VL 694
IS 2
BP 924
EP 942
DI 10.1088/0004-637X/694/2/924
PG 19
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 424AW
UT WOS:000264538900015
ER
PT J
AU Lin, YT
Partridge, B
Pober, JC
El Bouchefry, K
Burke, S
Klein, JN
Coish, JW
Huffenberger, KM
AF Lin, Yen-Ting
Partridge, Bruce
Pober, J. C.
El Bouchefry, Khadija
Burke, Sarah
Klein, Jonathan N.
Coish, Joseph W.
Huffenberger, Kevin M.
TI SPECTRAL ENERGY DISTRIBUTION OF RADIO SOURCES IN NEARBY CLUSTERS OF
GALAXIES: IMPLICATIONS FOR SUNYAEV-ZEL'DOVICH EFFECT SURVEYS
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE galaxies: active; galaxies: clusters: general; galaxies: elliptical and
lenticular, cD; radio continuum: galaxies
ID ATACAMA COSMOLOGY TELESCOPE; ABELL CLUSTERS; HIGH-FREQUENCY; VLA SURVEY;
STATISTICAL-METHODS; ASTRONOMICAL DATA; SOURCE POPULATION; POINT
SOURCES; UPPER LIMITS; 30 GHZ
AB To explore the high-frequency radio spectra of galaxies in clusters, we used NRAO's Very Large Array at four frequencies, 4.9-43 GHz, to observe 139 galaxies in low redshift (z < 0.25), X-ray detected, clusters. The clusters were selected from the survey conducted by Ledlow and Owen, who provided redshifts and 1.4 GHz flux densities for all the radio sources. We find that more than half of the observed sources have steep microwave spectra as generally expected (alpha < -0.5, in the convention S alpha nu(alpha)). However, 60%-70% of the unresolved or barely resolved sources have flat or inverted spectra. Most of these show an upward turn in flux at nu > 22 GHz, implying a higher flux than would be expected from an extrapolation of the lower-frequency flux measurements. Our results quantify the need for careful source subtraction in increasingly sensitive measurements of the Sunyaev-Zel'dovich effect in clusters of galaxies (as currently being conducted by, for instance, the Atacama Cosmology Telescope and South Pole Telescope groups).
C1 [Lin, Yen-Ting] Princeton Univ Observ, Princeton, NJ 08544 USA.
[Lin, Yen-Ting] Pontificia Univ Catolica Chile, Dept Astron & Astrofis, Santiago, Chile.
[Partridge, Bruce; Pober, J. C.; El Bouchefry, Khadija; Burke, Sarah; Klein, Jonathan N.; Coish, Joseph W.] Haverford Coll, Dept Astron, Haverford, PA 19041 USA.
[El Bouchefry, Khadija] Univ KwaZulu Natal, Astrophys & Cosmol Res Unit, Durban, South Africa.
[Burke, Sarah] Swinburne Univ Technol, Hawthorn, Vic 3122, Australia.
[Huffenberger, Kevin M.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
[Huffenberger, Kevin M.] Univ Miami, Dept Phys, Coral Gables, FL 33146 USA.
RP Lin, YT (reprint author), Univ Tokyo, Inst Phys & Math Universe, Tokyo 1138654, Japan.
EM yen-ting.lin@ipmu.jp; bpartrid@haverford.edu
OI Huffenberger, Kevin/0000-0001-7109-0099; Pober,
Jonathan/0000-0002-3492-0433
FU Princeton-Catolica Fellowship; NSF [OISE-0530095, AST-0606975];
FONDAP-Andes; World Premier International Research Center Initiative,
MEXT, Japan; NASA; Alfred P. Sloan Foundation; U.S. Department of
Energy; National Aeronautics and Space Administration; Japanese
Monbukagakusho; Max Planck Society; Higher Education Funding Council for
England
FX This research has made use of the NED and BAX databases, and the data
products from the NVSS and GB6 surveys.
NR 40
TC 39
Z9 39
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 APR 1
PY 2009
VL 694
IS 2
BP 992
EP 1009
DI 10.1088/0004-637X/694/2/992
PG 18
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 424AW
UT WOS:000264538900021
ER
PT J
AU Mroczkowski, T
Bonamente, M
Carlstrom, JE
Culverhouse, TL
Greer, C
Hawkins, D
Hennessy, R
Joy, M
Lamb, JW
Leitch, EM
Loh, M
Maughan, B
Marrone, DP
Miller, A
Muchovej, S
Nagai, D
Pryke, C
Sharp, M
Woody, D
AF Mroczkowski, Tony
Bonamente, Max
Carlstrom, John E.
Culverhouse, Thomas L.
Greer, Christopher
Hawkins, David
Hennessy, Ryan
Joy, Marshall
Lamb, James W.
Leitch, Erik M.
Loh, Michael
Maughan, Ben
Marrone, Daniel P.
Miller, Amber
Muchovej, Stephen
Nagai, Daisuke
Pryke, Clem
Sharp, Matthew
Woody, David
TI APPLICATION OF A SELF-SIMILAR PRESSURE PROFILE TO SUNYAEV-ZEL'DOVICH
EFFECT DATA FROM GALAXY CLUSTERS
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE cosmology: observations; galaxies: clusters: individual (Abell 1835,
Abell 1914, CL J1226.9+3332); X-rays: galaxies: clusters
ID RAY-IMAGING-SPECTROSCOPY; COSMIC DISTANCE SCALE; X-RAY; XMM-NEWTON;
TEMPERATURE PROFILES; HOT PLASMA; MASS; GAS; CONSTRAINTS; SAMPLE
AB We investigate the utility of a new, self-similar pressure profile for fitting Sunyaev-Zel'dovich (SZ) effect observations of galaxy clusters. Current SZ imaging instruments-such as the Sunyaev-Zel'dovich Array (SZA)-are capable of probing clusters over a large range in a physical scale. A model is therefore required that can accurately describe a cluster's pressure profile over a broad range of radii from the core of the cluster out to a significant fraction of the virial radius. In the analysis presented here, we fit a radial pressure profile derived from simulations and detailed X-ray analysis of relaxed clusters to SZA observations of three clusters with exceptionally high-quality X-ray data: A1835, A1914, and CL J1226.9+3332. From the joint analysis of the SZ and X-ray data, we derive physical properties such as gas mass, total mass, gas fraction and the intrinsic, integrated Compton y-parameter. We find that parameters derived from the joint fit to the SZ and X-ray data agree well with a detailed, independent X-ray-only analysis of the same clusters. In particular, we find that, when combined with X-ray imaging data, this new pressure profile yields an independent electron radial temperature profile that is in good agreement with spectroscopic X-ray measurements.
C1 [Mroczkowski, Tony; Miller, Amber] Columbia Univ, Columbia Astrophys Lab, New York, NY 10027 USA.
[Mroczkowski, Tony; Muchovej, Stephen] Columbia Univ, Dept Astron, New York, NY 10027 USA.
[Mroczkowski, Tony] Univ Penn, Dept Phys & Astron, Philadelphia, PA 19104 USA.
[Bonamente, Max] Univ Alabama, Dept Phys, Huntsville, AL 35899 USA.
[Bonamente, Max; Joy, Marshall] NASA, Dept Space Sci, George C Marshall Space Flight Ctr, Huntsville, AL 35899 USA.
[Carlstrom, John E.; Culverhouse, Thomas L.; Greer, Christopher; Hennessy, Ryan; Leitch, Erik M.; Loh, Michael; Marrone, Daniel P.; Pryke, Clem; Sharp, Matthew] Univ Chicago, Kavli Inst Cosmol Phys, Chicago, IL 60637 USA.
[Carlstrom, John E.; Culverhouse, Thomas L.; Greer, Christopher; Hennessy, Ryan; Leitch, Erik M.; Pryke, Clem] Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA.
[Carlstrom, John E.; Marrone, Daniel P.; Pryke, Clem] Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA.
[Carlstrom, John E.; Loh, Michael; Sharp, Matthew] Univ Chicago, Dept Phys, Chicago, IL 60637 USA.
[Hawkins, David; Lamb, James W.; Woody, David] CALTECH, Owens Valley Radio Observ, Big Pine, CA 93513 USA.
[Maughan, Ben] Univ Bristol, Dept Phys, Bristol BS8 1TL, Avon, England.
[Maughan, Ben] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA.
[Miller, Amber] Columbia Univ, Dept Phys, New York, NY 10027 USA.
[Nagai, Daisuke] Yale Univ, Dept Phys, New Haven, CT 06520 USA.
[Nagai, Daisuke] Yale Univ, Yale Ctr Astron Astrophys, New Haven, CT 06520 USA.
RP Mroczkowski, T (reprint author), Columbia Univ, Columbia Astrophys Lab, New York, NY 10027 USA.
OI Marrone, Daniel/0000-0002-2367-1080; Mroczkowski,
Tony/0000-0003-3816-5372
FU James S. McDonnell Foundation; National Science Foundation [AST-0604982,
PHY-0114422, AST-0507545, AST-05-07161]; University of Chicago; Sloan
Fellowship; NRAO Jansky Fellowship; Chandra Fellowship
FX We thank John Cartwright, Ben Reddall, and Marcus Runyan for their
significant contributions to the construction and commissioning of the
SZA instrument. We thank Esra Bulbul and Nicole Hasler for their
insights, comments, and help with Chandra X-ray Observatory (CXO) data
reduction and figure production. We thank the staff of the Owens Valley
Radio Observatory and CARMA for their outstanding support. We thank
Samuel LaRoque for his help with the modeling code. We gratefully
acknowledge the James S. McDonnell Foundation, the National Science
Foundation and the University of Chicago for funding to construct the
SZA. The operation of the SZA is supported by NSF Division of
Astronomical Sciences through grant AST-0604982. Partial support is
provided by NSF Physics Frontier Center grant PHY-0114422 to the Kavli
Institute of Cosmological Physics at the University of Chicago, and by
NSF grants AST-0507545 and AST-05-07161 to Columbia University. A. M.
acknowledges support from a Sloan Fellowship, D. P. M. from an NRAO
Jansky Fellowship, B. M. from a Chandra Fellowship, and C. G., S. M.,
and M. S. from NSF Graduate Research Fellowships.
NR 52
TC 49
Z9 49
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 APR 1
PY 2009
VL 694
IS 2
BP 1034
EP 1044
DI 10.1088/0004-637X/694/2/1034
PG 11
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 424AW
UT WOS:000264538900024
ER
PT J
AU van Belle, GT
von Braun, K
AF van Belle, Gerard T.
von Braun, Kaspar
TI DIRECTLY DETERMINED LINEAR RADII AND EFFECTIVE TEMPERATURES OF EXOPLANET
HOST STARS
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE infrared: stars; stars: fundamental parameters; techniques:
interferometric
ID PALOMAR TESTBED INTERFEROMETER; CHARA ARRAY; ANGULAR DIAMETERS; M
GIANTS; NEARBY STARS; COOL STARS; SUPERGIANTS; HIPPARCOS; CATALOG;
SYSTEMS
AB We present interferometric angular sizes for 12 stars with known planetary companions, for comparison with 28 additional main-sequence stars not known to host planets. For all objects we estimate bolometric fluxes and reddenings through spectral-energy distribution (SED) fits, and in conjunction with the angular sizes, measurements of effective temperature. The angular sizes of these stars are sufficiently small that the fundamental resolution limits of our primary instrument, the Palomar Testbed Interferometer, are investigated at the sub-milliarcsecond level and empirically established based upon known performance limits. We demonstrate that the effective temperature scale as a function of dereddened (V - K)(0) color is statistically identical for stars with and without planets. A useful byproduct of this investigation is a direct calibration of the T(EFF) scale for solarlike stars, as a function of both spectral type and (V - K)(0) color, with an precision of (Delta T) over bar ((V-K)0) = 138 K over the range (V - K)(0) = 0.0- 4.0 and (Delta T) over bar (SpType) = 105 K for the range F6V- G5V. Additionally, in an Appendix we provide SED fits for the 166 stars with known planets which have sufficient photometry available in the literature for such fits; this derived "XO-Rad" database includes homogeneous estimates of bolometric flux, reddening, and angular size.
C1 [van Belle, Gerard T.] European So Observ, D-85748 Garching, Germany.
[von Braun, Kaspar] NASA, CALTECH, Exoplanet Sci Inst, Pasadena, CA 91125 USA.
RP van Belle, GT (reprint author), European So Observ, Karl Schwarzschild Str 2, D-85748 Garching, Germany.
EM gerard.van.belle@eso.org; kaspar@ipac.caltech.edu
NR 45
TC 76
Z9 76
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 APR 1
PY 2009
VL 694
IS 2
BP 1085
EP 1098
DI 10.1088/0004-637X/694/2/1085
PG 14
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 424AW
UT WOS:000264538900029
ER
PT J
AU Reichardt, CL
Ade, PAR
Bock, JJ
Bond, JR
Brevik, JA
Contaldi, CR
Daub, MD
Dempsey, JT
Goldstein, JH
Holzapfel, WL
Kuo, CL
Lange, AE
Lueker, M
Newcomb, M
Peterson, JB
Ruhl, J
Runyan, MC
Staniszewski, Z
AF Reichardt, C. L.
Ade, P. A. R.
Bock, J. J.
Bond, J. R.
Brevik, J. A.
Contaldi, C. R.
Daub, M. D.
Dempsey, J. T.
Goldstein, J. H.
Holzapfel, W. L.
Kuo, C. L.
Lange, A. E.
Lueker, M.
Newcomb, M.
Peterson, J. B.
Ruhl, J.
Runyan, M. C.
Staniszewski, Z.
TI HIGH-RESOLUTION CMB POWER SPECTRUM FROM THE COMPLETE ACBAR DATA SET
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE cosmic microwave background; cosmology: observations
ID COSMIC BACKGROUND IMAGER; PROBE WMAP OBSERVATIONS;
HUBBLE-SPACE-TELESCOPE; NUMBER COUNTS; COSMOLOGICAL PARAMETERS; LOCKMAN
HOLE; 2003 FLIGHT; SUBMILLIMETER MAPS; POINT SOURCES; DARK ENERGY
AB In this paper, we present results from the complete set of cosmic microwave background (CMB) radiation temperature anisotropy observations made with the Arcminute Cosmology Bolometer Array Receiver (ACBAR) operating at 150 GHz. We include new data from the final 2005 observing season, expanding the number of detector hours by 210% and the sky coverage by 490% over that used for the previous ACBAR release. As a result, the band- power uncertainties have been reduced by more than a factor of two on angular scales encompassing the third to fifth acoustic peaks as well as the damping tail of the CMB power spectrum. The calibration uncertainty has been reduced from 6% to 2.1% in temperature through a direct comparison of the CMB anisotropy measured by ACBAR with that of the dipole-calibrated WMAP5 experiment. The measured power spectrum is consistent with a spatially flat, Lambda CDM cosmological model. We include the effects of weak lensing in the power spectrum model computations and find that this significantly improves the fits of the models to the combined ACBAR+WMAP5 power spectrum. The preferred strength of the lensing is consistent with theoretical expectations. On fine angular scales, there is weak evidence (1.1 sigma) for excess power above the level expected from primary anisotropies. We expect any excess power to be dominated by the combination of emission from dusty protogalaxies and the Sunyaev-Zel'dovich effect (SZE). However, the excess observed by ACBAR is significantly smaller than the excess power at l > 2000 reported by the CBI experiment operating at 30 GHz. Therefore, while it is unlikely that the CBI excess has a primordial origin; the combined ACBAR and CBI results are consistent with the source of the CBI excess being either the SZE or radio source contamination.
C1 [Reichardt, C. L.; Bock, J. J.; Brevik, J. A.; Kuo, C. L.; Lange, A. E.; Runyan, M. C.] CALTECH, Pasadena, CA 91125 USA.
[Ade, P. A. R.] Cardiff Univ, Dept Phys & Astron, Cardiff CF24 3YB, S Glam, Wales.
[Bock, J. J.; Lange, A. E.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
[Bond, J. R.] Univ Toronto, Canadian Inst Theoret Astrophys, Toronto, ON M5S 3H8, Canada.
[Contaldi, C. R.] Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2AZ, England.
[Daub, M. D.; Holzapfel, W. L.] Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA.
[Dempsey, J. T.] Joint Astron Ctr, Hilo, HI 96720 USA.
[Goldstein, J. H.; Ruhl, J.; Staniszewski, Z.] Case Western Reserve Univ, Dept Phys, Cleveland, OH 44106 USA.
[Goldstein, J. H.] Arete Associates, Arlington, VA 22202 USA.
[Kuo, C. L.] Stanford Univ, Dept Phys, Stanford, CA 94305 USA.
[Kuo, C. L.] Stanford Univ, KIPAC, Stanford, CA 94305 USA.
[Newcomb, M.] Univ Chicago, Yerkes Observ, Williams Bay, WI 53191 USA.
[Peterson, J. B.] Carnegie Mellon Univ, Dept Phys, Pittsburgh, PA 15213 USA.
RP Reichardt, CL (reprint author), CALTECH, MS 59-33, Pasadena, CA 91125 USA.
RI Peterson, Jeffrey/O-4794-2014; Holzapfel, William/I-4836-2015;
OI Peterson, Jeffrey/0000-0003-1340-818X; Reichardt,
Christian/0000-0003-2226-9169
NR 65
TC 273
Z9 273
U1 0
U2 7
PU IOP PUBLISHING LTD
PI BRISTOL
PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND
SN 0004-637X
EI 1538-4357
J9 ASTROPHYS J
JI Astrophys. J.
PD APR 1
PY 2009
VL 694
IS 2
BP 1200
EP 1219
DI 10.1088/0004-637X/694/2/1200
PG 20
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 424AW
UT WOS:000264538900038
ER
PT J
AU Madore, BF
Freedman, WL
Catanzarite, J
Navarrete, M
AF Madore, Barry F.
Freedman, Wendy L.
Catanzarite, Joseph
Navarrete, Mauricio
TI THE CEPHEID DISTANCE TO NGC 0247
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE Cepheids; galaxies: distances and redshifts; galaxies: individual (NGC
0247)
ID BVRI CCD PHOTOMETRY; GALAXIES; FIELD; DISCOVERY; VARIABLES; PROJECT;
NGC-300; PROGRAM; SCALE; STARS
AB We report VRI CCD observations of nine Cepheids in the South Polar (Sculptor) Group spiral galaxy NGC 0247. Periods of these Cepheids range from 20 to 70 days. Over the past 20 years, the brightest Cepheid in our sample, NGC 0247:[MF09] C1, has decreased its period by 6%, faded by 0.8 mag in the V band, and become bluer by 0.23 mag in (V-I). A multiwavelength analysis of the Cepheid data yields a true distance modulus of mu(o) = 27.81 +/- 0.10 mag (3.65 +/- 0.17 Mpc) with a total line-of-sight reddening of E(V-I) = 0.07 +/- 0.04 mag, after adopting an LMC true distance modulus of 18.5 mag and reddening of E(B-V) = 0.10 mag. These results are in excellent agreement with other very recently published (Cepheid and tip of the red giant branch) distances to NGC 0247. Combining both Cepheid data sets gives mu(o) = 27.85 +/- 0.09 mag (3.72 +/- 0.15 Mpc) with E(V-I) = 0.11 +/- 0.03 mag.
C1 [Madore, Barry F.; Freedman, Wendy L.] Carnegie Inst Washington, Pasadena, CA 91101 USA.
[Catanzarite, Joseph] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
[Navarrete, Mauricio] Carnegie Inst Washington, Las Campanas Observ, La Serena, Chile.
RP Madore, BF (reprint author), Carnegie Inst Washington, 813 Santa Barbara St, Pasadena, CA 91101 USA.
EM barry@ociw.edu; wendy@ociw.edu; joseph.h.catanzarite@jpl.nasa.gov;
mnavarrete@lco.cl
NR 18
TC 4
Z9 4
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 APR 1
PY 2009
VL 694
IS 2
BP 1237
EP 1249
DI 10.1088/0004-637X/694/2/1237
PG 13
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 424AW
UT WOS:000264538900041
ER
PT J
AU Budavari, T
Heinis, S
Szalay, AS
Nieto-Santisteban, M
Gupchup, J
Shiao, B
Smith, M
Chang, RX
Kauffmann, G
Morrissey, P
Schiminovich, D
Milliard, B
Wyder, TK
Martin, DC
Barlow, TA
Seibert, M
Forster, K
Bianchi, L
Donas, J
Friedman, PG
Heckman, TM
Lee, YW
Madore, BF
Neff, SG
Rich, RM
Welsh, BY
AF Budavari, Tamas
Heinis, Sebastien
Szalay, Alexander S.
Nieto-Santisteban, Maria
Gupchup, Jayant
Shiao, Bernie
Smith, Myron
Chang, Ruixiang
Kauffmann, Guinevere
Morrissey, Patrick
Schiminovich, David
Milliard, Bruno
Wyder, Ted K.
Martin, D. Christopher
Barlow, Tom A.
Seibert, Mark
Forster, Karl
Bianchi, Luciana
Donas, Jose
Friedman, Peter G.
Heckman, Timothy M.
Lee, Young-Wook
Madore, Barry F.
Neff, Susan G.
Rich, R. Michael
Welsh, Barry Y.
TI GALEX-SDSS CATALOGS FOR STATISTICAL STUDIES
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE catalogs; methods: statistical; surveys; ultraviolet: general
ID DIGITAL SKY SURVEY; GALAXY-EVOLUTION-EXPLORER; FOOTPRINT SERVICES;
REPRESENTATIONS; CLASSIFICATION; CALIBRATION; FITS
AB We present a detailed study of the Galaxy Evolution Explorer's (GALEX) photometric catalogs with special focus on the statistical properties of the All-sky and Medium Imaging Surveys. We introduce the concept of primaries to resolve the issue of multiple detections and follow a geometric approach to define clean catalogs with well understood selection functions. We cross-identify the GALEX sources (GR2+3) with Sloan Digital Sky Survey (SDSS; DR6) observations, which indirectly provides an invaluable insight into the astrometric model of the UV sources and allows us to revise the band merging strategy. We derive the formal description of the GALEX footprints as well as their intersections with the SDSS coverage along with analytic calculations of their areal coverage. The crossmatch catalogs are made available for the public. We conclude by illustrating the implementation of typical selection criteria in SQL for catalog subsets geared toward statistical analyses, e. g., correlation and luminosity function studies.
C1 [Budavari, Tamas; Heinis, Sebastien; Szalay, Alexander S.; Nieto-Santisteban, Maria; Bianchi, Luciana; Heckman, Timothy M.] Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA.
[Gupchup, Jayant] Johns Hopkins Univ, Dept Comp Sci, Baltimore, MD 21218 USA.
[Shiao, Bernie; Smith, Myron] Space Telescope Sci Inst, Baltimore, MD 21218 USA.
[Chang, Ruixiang] Shanghai Astron Observ, Shanghai 200030, Peoples R China.
[Kauffmann, Guinevere] Max Planck Inst Astrophys, D-85748 Garching, Germany.
[Morrissey, Patrick; Wyder, Ted K.; Martin, D. Christopher; Barlow, Tom A.; Forster, Karl; Friedman, Peter G.] CALTECH, Pasadena, CA 91125 USA.
[Schiminovich, David] Columbia Univ, Dept Astron, New York, NY 10027 USA.
[Milliard, Bruno; Donas, Jose] Lab Astrophys Marseille, F-13376 Marseille 12, France.
[Forster, Karl; Madore, Barry F.] Observ Carnegie Inst Washington, Pasadena, CA 91101 USA.
[Lee, Young-Wook] Yonsei Univ, Ctr Space Astrophys, Seoul 120749, South Korea.
[Neff, Susan G.] NASA, Goddard Space Flight Ctr, Astron & Solar Phys Lab, Greenbelt, MD 20771 USA.
[Rich, R. Michael] Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA.
[Welsh, Barry Y.] Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA.
RP Budavari, T (reprint author), Johns Hopkins Univ, Dept Phys & Astron, 3701 San Martin Dr, Baltimore, MD 21218 USA.
EM budavari@jhu.edu
FU NASA; National Science Foundation
FX GALEX is a NASA Small Explorer. We acknowledge NASA's support for
construction, operation, and science analysis for the GALEX mission,
developed in cooperation with the Centre National d'Etudes Spatiales of
France and the Korean Ministry of Science and Technology. This research
has made use of data obtained from and software provided by the US
National Virtual Observatory, which is sponsored by the National Science
Foundation. T. B. gratefully acknowledges support from the Gordon and
Betty Moore Foundation via GBMF 554.
NR 28
TC 40
Z9 41
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 APR 1
PY 2009
VL 694
IS 2
BP 1281
EP 1292
DI 10.1088/0004-637X/694/2/1281
PG 12
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 424AW
UT WOS:000264538900045
ER
PT J
AU Galametz, A
Stern, D
Eisenhardt, PRM
Brodwin, M
Brown, MJI
Dey, A
Gonzalez, AH
Jannuzi, BT
Moustakas, LA
Stanford, SA
AF Galametz, Audrey
Stern, Daniel
Eisenhardt, Peter R. M.
Brodwin, Mark
Brown, Michael J. I.
Dey, Arjun
Gonzalez, Anthony H.
Jannuzi, Buell T.
Moustakas, Leonidas A.
Stanford, S. Adam
TI THE COSMIC EVOLUTION OF ACTIVE GALACTIC NUCLEI IN GALAXY CLUSTERS
SO ASTROPHYSICAL JOURNAL
LA English
DT Article
DE galaxies: active; galaxies: clusters: general; galaxies: evolution;
infrared: galaxies; radio continuum: galaxies; X-rays: galaxies
ID DUST-OBSCURED GALAXIES; IRAC SHALLOW SURVEY; QSO REDSHIFT SURVEY; X-RAY
SURVEY; LUMINOSITY FUNCTION; RADIO GALAXIES; ENERGY-DISTRIBUTIONS; LARGE
POPULATION; SKY SURVEY; 1.4 GHZ
AB We present the surface density of luminous active galactic nuclei (AGNs) associated with a uniformly selected galaxy cluster sample identified in the 8.5 deg(2) Bootes field of the NOAO Deep Wide-Field Survey. The clusters are distributed over a large range of redshift (0 < z < 1.5), and we identify AGN using three different selection criteria: mid-IR color, radio luminosity, and X-ray luminosity. Relative to the field, we note a clear overdensity of the number of AGNs within 0.5 Mpc of the cluster centers at z > 0.5. The amplitude of this AGN overdensity increases with redshift. Although there are significant differences between the AGN populations probed by each selection technique, the rise in cluster AGN surface density generally increases more steeply than that of field quasars. In particular, X-ray-selected AGNs are at least 3 times more prevalent in clusters at 1 < z < 1.5 compared to clusters at 0.5 < z < 1. This effect is stronger than can be explained by the evolving median richness of our cluster sample. We thus confirm the existence of a Butcher-Oemler-type effect for AGN in galaxy clusters, with the number of AGNs in clusters increasing with redshift.
C1 [Galametz, Audrey; Stern, Daniel; Eisenhardt, Peter R. M.; Moustakas, Leonidas A.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
[Galametz, Audrey] European So Observ, D-85748 Garching, Germany.
[Galametz, Audrey] Observ Astron, F-67000 Strasbourg, France.
[Brodwin, Mark; Dey, Arjun; Jannuzi, Buell T.] Natl Opt Astron Observ, Tucson, AZ 85719 USA.
[Brown, Michael J. I.] Monash Univ, Sch Phys, Clayton, Vic 3800, Australia.
[Gonzalez, Anthony H.] Univ Florida, Dept Astron, Gainesville, FL 32611 USA.
[Stanford, S. Adam] Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA.
RP Galametz, A (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA.
EM agalamet@eso.org
RI Brown, Michael/B-1181-2015;
OI Brown, Michael/0000-0002-1207-9137; Moustakas,
Leonidas/0000-0003-3030-2360
FU National Optical Astronomy Observatory (NOAO); National Science
Foundation; NSF [AST-0708490]; University of California, Lawrence
Livermore National Laboratory [W-7405-Eng-48]
FX We thank the anonymous referee whose comments significantly improved
this paper. We thank Joel Vernet and Carlos De Breuck for carefully
reading the manuscript. This work is partly based on observations made
with the Spitzer Space Telescope, which is operated by the Jet
Propulsion Laboratory, California Institute of Technology under a
contract with NASA. This work made use of data products provided by the
NOAO Deep Wide- Field Survey, which is supported by the National Optical
Astronomy Observatory (NOAO). NOAO is operated by AURA, Inc., under a
cooperative agreement with the National Science Foundation. A. H. G.
acknowledges support from NSF grant AST-0708490. SAS's work was
performed under the auspices of the U. S. Department of Energy, National
Nuclear Security Administration by the University of California,
Lawrence Livermore National Laboratory under contract No. W-7405-Eng-48.
NR 59
TC 46
Z9 46
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 APR 1
PY 2009
VL 694
IS 2
BP 1309
EP 1316
DI 10.1088/0004-637X/694/2/1309
PG 8
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 424AW
UT WOS:000264538900047
ER
PT J
AU Daddi, E
Dannerbauer, H
Stern, D
Dickinson, M
Morrison, G
Elbaz, D
Giavalisco, M
Mancini, C
Pope, A
Spinrad, H
AF Daddi, E.
Dannerbauer, H.
Stern, D.
Dickinson, M.
Morrison, G.
Elbaz, D.
Giavalisco, M.
Mancini, C.
Pope, A.
Spinrad, H.
TI TWO BRIGHT SUBMILLIMETER GALAXIES IN A z=4.05 PROTOCLUSTER IN
GOODS-NORTH, AND ACCURATE RADIO-INFRARED PHOTOMETRIC REDSHIFTS
SO ASTROPHYSICAL JOURNAL
LA English
DT Review
DE cosmology: observations; galaxies: formation; galaxies: high-redshift;
galaxies: starburst; infrared: galaxies; submillimeter
ID STAR-FORMING GALAXIES; HUBBLE-DEEP-FIELD; DEGREE EXTRAGALACTIC SURVEY;
LYMAN-BREAK GALAXIES; SCUBA SUPER-MAP; MASSIVE GALAXIES; FORMATION
HISTORY; ELLIPTIC GALAXIES; EVOLVED GALAXIES; PASSIVE GALAXIES
AB We present the serendipitous discovery of molecular gas CO emission lines with the IRAM Plateau de Bure interferometer coincident with two luminous submillimeter galaxies (SMGs) in the Great Observatories Origins Deep Survey North (GOODS-N) field. The identification of the millimeter emission lines as CO[4-3] at z = 4.05 is based on the optical and near-IR photometric redshifts, radio-infrared photometric redshifts, and Keck+DEIMOS optical spectroscopy. These two galaxies include the brightest submillimeter source in the field (GN20; S-850 mu m = 20.3 mJy, z(CO) = 4.055 +/- 0.001) and its companion (GN20.2; S-850 mu m = 9.9 mJy, z(CO) = 4.051 +/- 0.003). These are among the most distant submillimeter-selected galaxies reliably identified through CO emission and also some of the most luminous known. GN20.2 has a possible additional counterpart and a luminous active galactic nucleus inside its primary counterpart revealed in the radio. Continuum emission of 0.3 mJy at 3.3 mm (0.65 mm in the rest frame) is detected at 5 sigma for GN20, the first dust continuum detection in an SMG at such long wavelength, unveiling a spectral energy distribution that is similar to local ultra luminous IR galaxies. In terms of CO to bolometric luminosities, stellar mass, and star formation rates (SFRs), these newly discovered z > 4 SMGs are similar to z similar to 2-3 SMGs studied to date. These z similar to 4 SMGs have much higher specific star formation rates than those of typical B-band dropout Lyman break galaxies at the same redshift. The stellar mass-SFR correlation for normal galaxies does not seem to evolve much further, between z similar to 2 and z similar to 4. A significant z = 4.05 spectroscopic redshift spike is observed in GOODS-N, and a strong spatial overdensity of B-band dropouts and IRAC selected z > 3.5 galaxies appears to be centered on the GN20 and GN20.2 galaxies. This suggests a protocluster structure with total mass similar to 10(14) M-circle dot. Using photometry at mid-IR ( 24 mu m), submillimeter (850 mu m), and radio (20 cm) wavelengths, we show that reliable photometric redshifts (Delta z/(1 + z) similar to 0.1) can be derived for SMGs over 1 less than or similar to z less than or similar to 4. This new photometric redshift technique has been used to provide a first estimate of the space density of 3.5 < z < 6 hyper-luminous starburst galaxies, and to show that they both contribute substantially to the SFR density at early epochs and that they can account for the presence of old galaxies at z similar to 2-3. Many of these high-redshift starbursts will be within reach of Herschel. We find that the criterion S-1.4 GHz greater than or similar to S-24 mu m, coupled to optical, near-IR and mid-IR photometry, can be used to select z > 3.5 starbursts, regardless of their submillimeter/millimeter emission.
C1 [Daddi, E.; Elbaz, D.; Mancini, C.] Univ Paris Diderot, CNRS, Lab AIM, CEA,Irfu SAp, F-91191 Gif Sur Yvette, France.
[Dannerbauer, H.] Max Planck Inst Astron, D-69117 Heidelberg, Germany.
[Stern, D.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
[Dickinson, M.; Pope, A.] Natl Opt Astron Observ, Tucson, AZ 85719 USA.
[Morrison, G.] Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA.
[Morrison, G.] Canada France Hawaii Telescope Corp, Kamuela, HI 96743 USA.
[Giavalisco, M.] Univ Massachusetts, Dept Astron, Amherst, MA 01003 USA.
[Mancini, C.] Univ Firenze, Dipartimento Astron, I-50100 Florence, Italy.
[Spinrad, H.] Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA.
RP Daddi, E (reprint author), Univ Paris Diderot, CNRS, Lab AIM, CEA,Irfu SAp, F-91191 Gif Sur Yvette, France.
EM edaddi@cea.fr
RI Daddi, Emanuele/D-1649-2012
OI Daddi, Emanuele/0000-0002-3331-9590
FU INSU/CNRS ( France); MPG ( Germany); IGN ( Spain); French ANR
[ANR-07-BLAN-0228, ANR-08-JCJC0008]; NASA [1224666]
FX This study is based on observations carried out with the IRAM Plateau de
Bure Interferometer. IRAM is supported by INSU/CNRS ( France), MPG (
Germany), and IGN ( Spain). We are grateful to Grant Wilson for sharing
with us unpublished information from the GOODS-N AzTEC supermap. We
thank Arancha Castro- Carrizo for assistance with the reduction of the
IRAM Plateau de Bure Interferometer data, and Ranga-Ram Chary for
discussions. Comments by an anonymous referee helped improving the
paper. We acknowledge the use of GILDAS software
(http://www.iram.fr/IRAMFR/GILDAS). E. D., C. M., and D. E. acknowledge
support from the French ANR grant numbers ANR-07-BLAN-0228 and
ANR-08-JCJC0008. The work of D. S. was carried out at Jet Propulsion
Laboratory, California Institute of Technology, under a contract with
NASA. Support for this work was provided by NASA, contract number
1224666 issued by the JPL, Caltech, under NASA contract 1407.
NR 116
TC 215
Z9 216
U1 0
U2 4
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 APR 1
PY 2009
VL 694
IS 2
BP 1517
EP 1538
DI 10.1088/0004-637X/694/2/1517
PG 22
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 424AW
UT WOS:000264538900065
ER
PT J
AU Kim, JH
Wise, JH
Abel, T
AF Kim, Ji-Hoon
Wise, John H.
Abel, Tom
TI GALAXY MERGERS WITH ADAPTIVE MESH REFINEMENT: STAR FORMATION AND HOT GAS
OUTFLOW
SO ASTROPHYSICAL JOURNAL LETTERS
LA English
DT Article
DE galaxies: formation; galaxies: interactions; galaxies: starburst; stars:
formation
ID SMOOTHED PARTICLE HYDRODYNAMICS; FORMING GALAXIES; INTERSTELLAR-MEDIUM;
MULTIPHASE MODEL; MAJOR MERGERS; DISK GALAXIES; HOST GALAXIES;
SIMULATIONS; FEEDBACK; GASDYNAMICS
AB In hierarchical structure formation, merging of galaxies is frequent and known to dramatically affect their properties. To comprehend these interactions high-resolution simulations are indispensable because of the nonlinear coupling between pc and Mpc scales. To this end, we present the first adaptive mesh refinement (AMR) simulation of two merging, low mass, initially gas-rich galaxies (1.8 x 10(10) M(circle dot) each), including star formation and feedback. With galaxies resolved by similar to 2 x 10(7) total computational elements, we achieve unprecedented resolution of the multiphase interstellar medium, finding a widespread starburst in the merging galaxies via shock-induced star formation. The high dynamic range of AMR also allows us to follow the interplay between the galaxies and their embedding medium depicting how galactic outflows and a hot metal-rich halo form. These results demonstrate that AMR provides a powerful tool in understanding interacting galaxies.
C1 [Kim, Ji-Hoon; Abel, Tom] Kavli Inst Particle Astrophys & Cosmol, SLAC Natl Accelerator Lab, Menlo Pk, CA USA.
[Kim, Ji-Hoon; Abel, Tom] Stanford Univ, Dept Phys, Stanford, CA 94305 USA.
[Wise, John H.] NASA, Goddard Space Flight Ctr, Lab Astron & Cosmol, Greenbelt, MD 20771 USA.
RP Kim, JH (reprint author), Kavli Inst Particle Astrophys & Cosmol, SLAC Natl Accelerator Lab, Menlo Pk, CA USA.
EM mornkr@slac.stanford.edu
FU NASA ATFP grant [NNX08AH26G]; NSF [AST-0807312]
FX We thank Marcelo Alvarez, T. J. Cox, Andres Escala, Kristian Finlator,
Yuexing Li, Changbom Park, Cecilia Scannapieco, Volker Springel,
Elizabeth Tasker, Matthew Turk, Peng Wang, and Risa Wechsler for
insightful comments and advice. J. K. was supported by William R. and
Sara Hart Kimball Stanford Graduate Fellowship. J. H. W. was supported
by an appointment to the NASA Postdoctoral Program, administered by Oak
Ridge Associated Universities. This work was partially supported by NASA
ATFP grant NNX08AH26G and NSF AST-0807312. These calculations were
performed on 32 processors of the Orange cluster at KIPAC.
NR 44
TC 27
Z9 27
U1 0
U2 1
PU IOP PUBLISHING LTD
PI BRISTOL
PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND
J9 ASTROPHYS J LETT
JI Astrophys. J. Lett.
PD APR 1
PY 2009
VL 694
IS 2
BP L123
EP L127
DI 10.1088/0004-637X/694/2/L123
PG 5
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 419CL
UT WOS:000264196600008
ER
PT J
AU Evans, NJ
Dunham, MM
Jorgensen, JK
Enoch, ML
Merin, B
van Dishoeck, EF
Alcala, JM
Myers, PC
Stapelfeldt, KR
Huard, TL
Allen, LE
Harvey, PM
van Kempen, T
Blake, GA
Koerner, DW
Mundy, LG
Padgett, DL
Sargent, AI
AF Evans, Neal J., II
Dunham, Michael M.
Jorgensen, Jes K.
Enoch, Melissa L.
Merin, Bruno
van Dishoeck, Ewine F.
Alcala, Juan M.
Myers, Philip C.
Stapelfeldt, Karl R.
Huard, Tracy L.
Allen, Lori E.
Harvey, Paul M.
van Kempen, Tim
Blake, Geoffrey A.
Koerner, David W.
Mundy, Lee G.
Padgett, Deborah L.
Sargent, Anneila I.
TI THE SPITZER c2d LEGACY RESULTS: STAR-FORMATION RATES AND EFFICIENCIES;
EVOLUTION AND LIFETIMES
SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
LA English
DT Review
DE dust, extinction; infrared: stars; ISM: clouds; stars: formation
ID YOUNG STELLAR OBJECTS; INITIAL MASS FUNCTION; MAIN-SEQUENCE STARS;
SPECTRAL ENERGY-DISTRIBUTIONS; AURIGA MOLECULAR CLOUD; II DARK CLOUD;
T-TAURI STARS; SPACE-TELESCOPE OBSERVATIONS; DUST CONTINUUM EMISSION;
RHO-OPHIUCHI CLOUD
AB The c2d Spitzer Legacy project obtained images and photometry with both IRAC and MIPS instruments for five large, nearby molecular clouds. Three of the clouds were also mapped in dust continuum emission at 1.1 mm, and optical spectroscopy has been obtained for some clouds. This paper combines information drawn from studies of individual clouds into a combined and updated statistical analysis of star-formation rates and efficiencies, numbers and lifetimes for spectral energy distribution (SED) classes, and clustering properties. Current star-formation efficiencies range from 3% to 6%; if star formation continues at current rates for 10 Myr, efficiencies could reach 15-30%. Star-formation rates and rates per unit area vary from cloud to cloud; taken together, the five clouds are producing about 260 M(circle dot) of stars per Myr. The star-formation surface density is more than an order of magnitude larger than would be predicted from the Kennicutt relation used in extragalactic studies, reflecting the fact that those relations apply to larger scales, where more diffuse matter is included in the gas surface density. Measured against the dense gas probed by the maps of dust continuum emission, the efficiencies are much higher, with stellar masses similar to masses of dense gas, and the current stock of dense cores would be exhausted in 1.8 Myr on average. Nonetheless, star formation is still slow compared to that expected in a free-fall time, even in the dense cores. The derived lifetime for the Class I phase is 0.54 Myr, considerably longer than some estimates. Similarly, the lifetime for the Class 0 SED class, 0.16 Myr, with the notable exception of the Ophiuchus cloud, is longer than early estimates. If photometry is corrected for estimated extinction before calculating class indicators, the lifetimes drop to 0.44 Myr for Class I and to 0.10 for Class 0. These lifetimes assume a continuous flow through the Class II phase and should be considered median lifetimes or half-lives. Star formation is highly concentrated to regions of high extinction, and the youngest objects are very strongly associated with dense cores. The great majority (90%) of young stars lie within loose clusters with at least 35 members and a stellar density of 1 M(circle dot) pc(-3). Accretion at the sound speed from an isothermal sphere over the lifetime derived for the Class I phase could build a star of about 0.25 M(circle dot), given an efficiency of 0.3. Building larger mass stars by using higher mass accretion rates could be problematic, as our data confirm and aggravate the "luminosity problem" for protostars. At a given T(bol), the values for L(bol) are mostly less than predicted by standard infall models and scatter over several orders of magnitude. These results strongly suggest that accretion is time variable, with prolonged periods of very low accretion. Based on a very simple model and this sample of sources, half the mass of a star would be accreted during only 7% of the Class I lifetime, as represented by the eight most luminous objects.
C1 [Evans, Neal J., II; Dunham, Michael M.; Harvey, Paul M.] Univ Texas Austin, Dept Astron, Austin, TX 78712 USA.
[Jorgensen, Jes K.] Univ Bonn, Argelander Inst Astron, D-53121 Bonn, Germany.
[Enoch, Melissa L.; Sargent, Anneila I.] CALTECH, Div Phys Math & Astron, Pasadena, CA 91125 USA.
[Enoch, Melissa L.] Univ Calif Berkeley, Berkeley, CA 94720 USA.
[Merin, Bruno; van Dishoeck, Ewine F.; van Kempen, Tim] Leiden Univ, Leiden Observ, NL-2300 RA Leiden, Netherlands.
[Merin, Bruno] European Space Technol Ctr, European Space Agcy, Res & Sci Support Dept, NL-2200 AG Noordwijk, Netherlands.
[van Dishoeck, Ewine F.] Max Planck Inst Extraterr Phys, D-85748 Garching, Germany.
[Alcala, Juan M.] Osserv Astron Capodimonte, INAF, I-80131 Naples, Italy.
[Myers, Philip C.; Huard, Tracy L.; Allen, Lori E.] Harvard Univ, Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA.
[Stapelfeldt, Karl R.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
[Huard, Tracy L.; Mundy, Lee G.] Univ Maryland, Dept Astron, College Pk, MD 20742 USA.
[Blake, Geoffrey A.] CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA.
[Koerner, David W.] No Arizona Univ, Dept Phys & Astron, Flagstaff, AZ 86011 USA.
[Padgett, Deborah L.] CALTECH, Spitzer Sci Ctr, Pasadena, CA 91125 USA.
RP Evans, NJ (reprint author), Univ Texas Austin, Dept Astron, 1 Univ Stn,C1400, Austin, TX 78712 USA.
EM nje@astro.as.utexas.edu; mdunham@astro.as.utexas.edu;
jes@astro.uni-bonn.de; bmerin@rssd.esa.int; ewine@strw.LeidenUniv.nl;
alcala@oacn.inaf.it; pmyers@cfa.harvard.edu; krs@exoplanet.jpl.nasa.gov;
thuard@astro.umd.edu; leallen@cfa.harvard.edu; pmh@astro.as.utexas.edu;
gab@gps.caltech.edu; david.koerner@nau.edu; lgm@astro.umd.edu;
dlp@ipac.caltech.edu; afs@astro.caltech.edu
RI Stapelfeldt, Karl/D-2721-2012;
OI Alcala, Juan Manuel/0000-0001-8657-095X; Merin,
Bruno/0000-0002-8555-3012
FU NASA [1224608, 1230779, 1288658, 1288664, 1230782, 1407, NNG04GG24G,
NNX07AJ72G]; NSF [NSF PHY05-51164]; NWO Spinoza; NOVA
FX We thank the referee, Charles Lada, for a very thought-provoking report,
which helped us to improve the clarity of the paper. We thank the
Lorentz Center in Leiden for hosting several meetings that contributed
to this paper. Part of the work was done while in residence at the Kavli
Institute for Theoretical Physics in Santa Barbara, California. We thank
M. Krumholz for enlightening discussions and derivations of the speed of
star formation in dense gas and F. Comeron for drawing our attention to
biases caused by low-mass objects dropping out of the sample as they
age. We are also grateful to D. Ward-Thompson for helpful suggestions.
Support for this work, part of the Spitzer Legacy Science Program, was
provided by NASA through contracts 1224608, 1230779, 1288658, 1288664,
and 1230782 issued by the Jet Propulsion Laboratory, California
Institute of Technology, under NASA contract 1407. Additional support
came from NASA Origins grants NNG04GG24G and NNX07AJ72G to N.J.E. While
several coauthors were at the Kavli Institute, the research was
supported in part by the NSF under Grant No. NSF PHY05-51164. M. L. E.
acknowledges support of an NSF Graduate Research Fellowship and a
Spitzer Space Telescope Postdoctoral Fellowship. Astrochemistry in
Leiden is supported by a NWO Spinoza grant and a NOVA grant.
NR 179
TC 649
Z9 651
U1 3
U2 14
PU IOP PUBLISHING LTD
PI BRISTOL
PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND
SN 0067-0049
J9 ASTROPHYS J SUPPL S
JI Astrophys. J. Suppl. Ser.
PD APR
PY 2009
VL 181
IS 2
BP 321
EP 350
DI 10.1088/0067-0049/181/2/321
PG 30
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 426ZF
UT WOS:000264746700001
ER
PT J
AU Nielsen, KE
Kober, GV
Weis, K
Gull, TR
Stahl, O
Bomans, DJ
AF Nielsen, K. E.
Kober, G. Vieira
Weis, K.
Gull, T. R.
Stahl, O.
Bomans, D. J.
TI ETA CARINAE ACROSS THE 2003.5 MINIMUM: ANALYSIS IN THE VISIBLE AND
NEAR-INFRARED SPECTRAL REGION
SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
LA English
DT Article
DE circumstellar matter; line: identification; stars: individual (eta Car)
ID OSCILLATOR-STRENGTHS; HOMUNCULUS-NEBULA; FE-II; STELLAR EVOLUTION;
EJECTA ABSORPTION; CAR CAMPAIGN; ULTRAVIOLET; SPECTROSCOPY; EMISSION;
LINES
AB We present an analysis of the visible through near-infrared spectrum of Eta Carinae (eta Car) and its ejecta obtained during the "eta Car Campaign with the Ultraviolet and Visual Echelle Spectrograph (UVES) at the ESO Very Large Telescope (VLT)." This is a part of larger effort to present a complete eta Car spectrum, and extends the previously presented analyses with the Hubble Space Telescope/Space Telescope Imaging Spectrograph (HST/STIS) in the UV (1240-3159 angstrom) to 10,430 angstrom. The spectrum in the mid- and near-UV is characterized by the ejecta absorption. At longer wavelengths, stellar wind features from the central source and narrow-emission lines from the Weigelt condensations dominate the spectrum. However, narrow absorption lines from the circumstellar shells are present. This paper provides a description of the spectrum between 3060 and 10,430 angstrom, including line identifications of the ejecta absorption spectrum, the emission spectrum from the Weigelt condensations and the P Cygni stellar wind features. The high spectral resolving power of VLT/UVES enables equivalent width measurements of atomic and molecular absorption lines for elements with no transitions at the shorter wavelengths. However, the ground-based seeing and contributions of nebular-scattered radiation prevent direct comparison of measured equivalent widths in the VLT/UVES and HST/STIS spectra. Fortunately, HST/STIS and VLT/UVES have a small overlap in wavelength coverage which allows us to compare and adjust for the difference in scattered radiation entering the instruments' apertures. This paper provides a complete online VLT/UVES spectrum with line identifications and a spectral comparison between HST/STIS and VLT/UVES between 3060 and 3160 angstrom.
C1 [Nielsen, K. E.; Kober, G. Vieira] Catholic Univ Amer, Washington, DC 20064 USA.
[Nielsen, K. E.; Kober, G. Vieira; Gull, T. R.] NASA, Goddard Space Flight Ctr, Astrophys Sci Div, Greenbelt, MD 20771 USA.
[Weis, K.; Bomans, D. J.] Ruhr Univ Bochum, Astron Inst, D-44780 Bochum, Germany.
[Stahl, O.] Heidelberg Univ, ZAH, Landessternwarte Konigstuhl, D-69117 Heidelberg, Germany.
RP Nielsen, KE (reprint author), Catholic Univ Amer, Washington, DC 20064 USA.
EM krister.nielsen@nasa.gov
RI Gull, Theodore/D-2753-2012
OI Gull, Theodore/0000-0002-6851-5380
NR 63
TC 8
Z9 8
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 APR
PY 2009
VL 181
IS 2
BP 473
EP 485
DI 10.1088/0067-0049/181/2/473
PG 13
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 426ZF
UT WOS:000264746700012
ER
PT J
AU Cheung, CC
Healey, SE
Landt, H
Kleijn, GV
Jordan, A
AF Cheung, C. C.
Healey, Stephen E.
Landt, Hermine
Kleijn, Gijs Verdoes
Jordan, Andres
TI FIRST "WINGED" AND X-SHAPED RADIO SOURCE CANDIDATES. II. NEW REDSHIFTS
SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
LA English
DT Article
DE galaxies: active; galaxies: distances and redshifts; quasars: general
ID BL LACERTAE OBJECTS; REVISED 3C CATALOG; ABELL CLUSTERS; BLACK-HOLE;
OPTICAL SPECTROSCOPY; SURFACE PHOTOMETRY; GALAXY NGC-326; SKY SURVEY;
VLA SURVEY; EMISSION
AB We report optical spectroscopic observations of X-shaped radio sources with the Hobby-Eberly Telescope and Multiple-Mirror Telescope, focused on the sample of candidates from the FIRST survey presented in a previous paper. A total of 27 redshifts were successfully obtained, 21 of which are new, including a newly identified candidate source of this type which is presented here. With these observations, the sample of candidates from the previous paper is over 50% spectroscopically identified. Two new broad emission-lined X-shaped radio sources are revealed, while no emission lines were detected in about one-third of the observed sources; a detailed study of the line properties is deferred to a future paper. Finally, to explore their relation to the Fanaroff Riley division, the radio luminosities and host galaxy absolute magnitudes of a spectroscopically identified sample of 50 X-shaped radio galaxies are calculated to determine their placement in the Owen-Ledlow plane.
C1 [Cheung, C. C.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
[Cheung, C. C.; Healey, Stephen E.] Stanford Univ, Kavli Inst Particle Astrophys & Cosmol, Stanford, CA 94305 USA.
[Healey, Stephen E.] Stanford Univ, Dept Phys, Stanford, CA 94305 USA.
[Landt, Hermine; Jordan, Andres] Harvard Univ, Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA.
[Kleijn, Gijs Verdoes] Univ Groningen, Kapteyn Astron Inst, NL-9700 AV Groningen, Netherlands.
[Jordan, Andres] European So Observ, D-85748 Garching, Germany.
RP Cheung, CC (reprint author), NASA, Goddard Space Flight Ctr, Code 661, Greenbelt, MD 20771 USA.
EM Teddy.Cheung@nasa.gov
OI Jordan, Andres/0000-0002-5389-3944
FU National Science Foundation; NASA; DOE DE-AC03-76SF00515; University of
Texas at Austin; Pennsylvania State University; Stanford University;
Ludwig-Maximillians-Universitat Munchen; Georg-August-Universitat
Gottingen; HET; Instituto de Astronomia de la Universidad Nacional
Autonoma de Mexico
FX C. C. C. was supported by the National Radio Astronomy Observatory
(2004-2007), which is operated by Associated Universities, Inc. under a
cooperative agreement with the National Science Foundation, and
currently by an appointment to the NASA Postdoctoral Program at Goddard
Space Flight Center, administered by Oak Ridge Associated Universities
through a contract with NASA. S. E. H. is supported by the Stanford
Linear Accelerator Center under DOE contract DE-AC03-76SF00515. C. C. C.
is grateful to the MMT staff, particularly Mike Alegria and Grant
Williams for their assistance during the observing run, and Alessondra
Springmann for her assistance during a clouded out MMT run in July 2006.
The MMT is a facility operated jointly by the University of Arizona and
the Smithsonian Institution.; The Hobby-Eberly Telescope is a joint
project of the University of Texas at Austin, the Pennsylvania State
University, Stanford University, Ludwig-Maximillians-Universitat
Munchen, and Georg-August-Universitat Gottingen. The HET is named in
honor of its principal benefactors, William P. Hobby and Robert E.
Eberly. The Marcario Low-Resolution Spectrograph is named for Mike
Marcario of High Lonesome Optics, who fabricated several optics for the
instrument but died before its completion; it is a joint project of the
HET partnership and the Instituto de Astronomia de la Universidad
Nacional Autonoma de Mexico. This paper includes data taken with the
Harlan J. Smith Telescope at the McDonald Observatory of the University
of Texas at Austin.; This research has made use of NASA's Astrophysics
Data System Abstract Service and the NASA/IPAC Extragalactic Database
(NED) which is operated by the Jet Propulsion Laboratory, California
Institute of Technology, under contract with the National Aeronautics
and Space Administration.
NR 48
TC 12
Z9 12
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 APR
PY 2009
VL 181
IS 2
BP 548
EP 556
DI 10.1088/0067-0049/181/2/548
PG 9
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 426ZF
UT WOS:000264746700016
ER
PT J
AU Brassington, NJ
Fabbiano, G
Kim, DW
Zezas, A
Zepf, S
Kundu, A
Angelini, L
Davies, RL
Gallagher, J
Kalogera, V
Fragos, T
King, AR
Pellegrini, S
Trinchieri, G
AF Brassington, N. J.
Fabbiano, G.
Kim, D. -W.
Zezas, A.
Zepf, S.
Kundu, A.
Angelini, L.
Davies, R. L.
Gallagher, J.
Kalogera, V.
Fragos, T.
King, A. R.
Pellegrini, S.
Trinchieri, G.
TI DEEP CHANDRA MONITORING OBSERVATIONS OF NGC 4278: CATALOG OF SOURCE
PROPERTIES
SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
LA English
DT Article
DE galaxies: individual (NGC 4278); X-rays: binaries; X-rays: galaxies
ID X-RAY BINARIES; GLOBULAR-CLUSTER SYSTEMS; MULTIWAVELENGTH PROJECT;
ELLIPTIC GALAXIES; LUMINOSITY FUNCTION; SOURCE POPULATION; NEARBY
GALAXIES; POINT SOURCES; CENTAURUS-A; DISTANCES
AB We present the properties of the discrete X-ray sources detected in our monitoring program of the globular cluster ( GC) rich elliptical galaxy, NGC 4278, observed with Chandra ACIS-S in six separate pointings, resulting in a co-added exposure of 458 ks. From this deep observation, 236 sources have been detected within the region overlapped by all observations, 180 of which lie within the D(25) ellipse of the galaxy. These 236 sources range in L(X) from 3.5 x 10(36) erg s(-1) ( with 3 sigma upper limit <= 1 x 10(37) erg s(-1)) to similar to 2 x 10(40) erg s(-1), including the central nuclear source which has been classified as a LINER. From optical data, 39 X-ray sources have been determined to be coincident with a GC, these sources tend to have high X-ray luminosity, with 10 of these sources exhibiting L(X) > 1 x 10(38) erg s(-1). From X-ray source photometry, it has been determined that the majority of the 236 point sources that have well-constrained colors have values that are consistent with typical low-mass X-ray binary spectra, with 29 of these sources expected to be background objects from the log N - log S relation. There are 103 sources in this population that exhibit long-term variability, indicating that they are accreting compact objects. Three of these sources have been identified as transient candidates, with a further three possible transients. Spectral variations have also been identified in the majority of the source population, where a diverse range of variability has been identified, indicating that there are many different source classes located within this galaxy.
C1 [Brassington, N. J.; Fabbiano, G.; Kim, D. -W.; Zezas, A.] Harvard Univ, Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA.
[Zepf, S.; Kundu, A.] Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA.
[Angelini, L.] NASA, Goddard Space Flight Ctr, Lab Xray Astrophys, Greenbelt, MD 20771 USA.
[Davies, R. L.] Univ Oxford, Sub Dept Astrophys, Oxford OX1 3RH, England.
[Gallagher, J.] Univ Wisconsin, Dept Astron, Madison, WI 53706 USA.
[Kalogera, V.; Fragos, T.] Northwestern Univ, Dept Phys & Astron, Evanston, IL 60208 USA.
[King, A. R.] Univ Leicester, Theoret Astrophys Grp, Leicester LE1 7RH, Leics, England.
[Pellegrini, S.] Univ Bologna, Dipartimento Astron, I-40127 Bologna, Italy.
[Trinchieri, G.] Osserv Astron Brera, INAF, I-20121 Milan, Italy.
RP Brassington, NJ (reprint author), Harvard Univ, Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA.
EM nbrassington@head.cfa.harvard.edu
RI Zezas, Andreas/C-7543-2011; Fragos, Tassos/A-3581-2016
OI Zezas, Andreas/0000-0001-8952-676X; Trinchieri,
Ginevra/0000-0002-0227-502X; Fragos, Tassos/0000-0003-1474-1523
FU Chandra G0 [G06-7079A, G06-7079B]; NASA [NAS8-3907, NAG5-13056]; Italian
Space Agency ASI (Agenzia Spaziale Italiana) [ASI-INAF I/023/05/0]
FX We thank the CXC DS and SDS teams for their efforts in reducing the data
and developing the software used for the reduction (SDP) and analysis
(CIAO). We also thank the referee, Jimmy Irwin, for his helpful comments
which have improved this paper. This work was supported by Chandra G0
grant G06-7079A (PI: Fabbiano) and subcontract G06-7079B (PI: Kalogera).
We acknowledge partial support from NASA contract NAS8-39073 (CXC). A.
Zezas acknowledges support from NASA LTSA grant NAG5-13056. S.
Pellegrini acknowledges partial financial support from the Italian Space
Agency ASI (Agenzia Spaziale Italiana) through grant ASI-INAF
I/023/05/0.
NR 40
TC 29
Z9 29
U1 1
U2 2
PU IOP PUBLISHING LTD
PI BRISTOL
PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND
SN 0067-0049
J9 ASTROPHYS J SUPPL S
JI Astrophys. J. Suppl. Ser.
PD APR
PY 2009
VL 181
IS 2
BP 605
EP 626
DI 10.1088/0067-0049/181/2/605
PG 22
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 426ZF
UT WOS:000264746700019
ER
PT J
AU Bufano, F
Immler, S
AF Bufano, Filomena
Immler, Stefan
TI Ultraviolet SN observations with Swift
SO ASTROPHYSICS AND SPACE SCIENCE
LA English
DT Article; Proceedings Paper
CT Conference on Network for Ultra Violet Astronomy
CY JUN, 2007
CL Madrid, SPAIN
DE Supernovae; Ultraviolet: general
ID I SUPERNOVAE; TELESCOPE; MODELS; 2006JC; STAR
AB Ultraviolet (UV) data are powerful tools to understand supernovae (SNe). Currently, the Swift satellite is the best suited telescope available for SN UV studies, due to its photometric and spectroscopic capabilities and its fast response. We present recent results obtained with the Swift SN program, demonstrating the importance of the UV emission, which provides fundamental information about SN explosion mechanism, its environment and progenitor structure.
C1 [Bufano, Filomena] Univ Padua, Dipartimento Astron, I-35122 Padua, Italy.
[Bufano, Filomena] Osserv Astron Padova, INAF, I-35122 Padua, Italy.
[Bufano, Filomena; Immler, Stefan] NASA, Goddard Space Flight Ctr, Astrophys Sci Div, Swift Supernova Team, Greenbelt, MD 20771 USA.
RP Bufano, F (reprint author), Univ Padua, Dipartimento Astron, Vicolo Osservatorio 2, I-35122 Padua, Italy.
EM filomena.bufano@oapd.inaf.it
NR 21
TC 0
Z9 0
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 APR
PY 2009
VL 320
IS 1-3
BP 173
EP 176
DI 10.1007/s10509-008-9791-x
PG 4
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 418UK
UT WOS:000264174700028
ER
PT J
AU Roming, PWA
Gronwall, C
Berk, DEV
Page, MJ
Boyd, PT
AF Roming, P. W. A.
Gronwall, C.
Berk, D. E. Vanden
Page, M. J.
Boyd, P. T.
TI The Swift Ultra-Violet/Optical Telescope: a view of today and tomorrow
SO ASTROPHYSICS AND SPACE SCIENCE
LA English
DT Article; Proceedings Paper
CT Conference on Network for Ultra Violet Astronomy
CY JUN, 2007
CL Madrid, SPAIN
DE Space vehicles: instruments; Ultraviolet: general; Gamma rays: bursts
ID EARLY OPTICAL AFTERGLOWS; X-RAY; ULTRAVIOLET VARIABILITY; UVOT
OBSERVATIONS; MISSION; SUPERNOVA; EVOLUTION; GALAXIES; REGIONS; BURSTS
AB Currently there are four operating near-UV imaging space telescopes, one of which is the Swift Ultra-Violet/Optical Telescope (UVOT). Although the UVOT was primarily built for observations of gamma-ray bursts, it has become a powerful instrument for studying other types of UV and optical astronomical phenomena. Here we discuss the properties of the UVOT, summarize some of the science undertaken with the UVOT, and present other possible science goals for the UVOT that have not yet been pursued. We also discuss some lessons learned that apply to future UV telescopes.
C1 [Roming, P. W. A.; Gronwall, C.; Berk, D. E. Vanden] Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA.
[Page, M. J.] Univ Coll London, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England.
[Boyd, P. T.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
RP Roming, PWA (reprint author), Penn State Univ, Dept Astron & Astrophys, 525 Davey Lab, University Pk, PA 16802 USA.
EM roming@astro.psu.edu
RI Boyd, Patricia/D-3274-2012
NR 33
TC 3
Z9 3
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 APR
PY 2009
VL 320
IS 1-3
BP 203
EP 206
DI 10.1007/s10509-008-9813-8
PG 4
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 418UK
UT WOS:000264174700034
ER
PT J
AU Carpenter, KG
Schrijver, CJ
Karovska, M
AF Carpenter, Kenneth G.
Schrijver, Carolus J.
Karovska, Margarita
TI The Stellar Imager (SI) project: a deep space UV/Optical Interferometer
(UVOI) to observe the Universe at 0.1 milli-arcsec angular resolution
SO ASTROPHYSICS AND SPACE SCIENCE
LA English
DT Article; Proceedings Paper
CT Conference on Network for Ultra Violet Astronomy
CY JUN, 2007
CL Madrid, SPAIN
DE Observatories: space; Interferometry: space; Stars: surface features;
Stars: interiors; Galaxies: AGN; Planets: Exo-Solar
AB The Stellar Imager (SI) is a space-based, UV/Optical Interferometer (UVOI) designed to enable 0.1 milli-arcsecond (mas) spectral imaging of stellar surfaces and of the Universe in general. It will also probe via asteroseismology flows and structures in stellar interiors. SI's science focuses on the role of magnetism in the Universe and will revolutionize our understanding of the formation of planetary systems, of the habitability and climatology of distant planets, and of many magneto-hydrodynamically controlled processes, such as accretion, in the Universe. The ultra-sharp images of SI will revolutionize our view of many dynamic astrophysical processes by transforming point sources into extended sources, and snapshots into evolving views. SI is a "Flagship and Landmark Discovery Mission" in the 2005 Heliophysics Roadmap and a potential implementation of the UVOI in the 2006 Science Program for NASA's Astronomy and Physics Division. We present here the science goals of the SI Mission, a mission architecture that could meet those goals, and the technology development needed to en-able this mission. Additional information on SI can be found at: http://hires.gsfc.nasa.gov/si/.
C1 [Carpenter, Kenneth G.] NASA, Goddard Space Flight Ctr, Exoplanets & Stellar Astrophys Lab, Greenbelt, MD 20771 USA.
[Schrijver, Carolus J.] Lockheed Martin Adv Technol Ctr, Palo Alto, CA 94304 USA.
[Karovska, Margarita] SAO, Cambridge, MA 02138 USA.
RP Carpenter, KG (reprint author), NASA, Goddard Space Flight Ctr, Exoplanets & Stellar Astrophys Lab, Code 667, Greenbelt, MD 20771 USA.
EM Kenneth.G.Carpenter@nasa.gov
RI Carpenter, Kenneth/D-4740-2012
NR 8
TC 11
Z9 11
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 APR
PY 2009
VL 320
IS 1-3
BP 217
EP 223
DI 10.1007/s10509-008-9815-6
PG 7
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 418UK
UT WOS:000264174700036
ER
PT J
AU Yorks, JE
Thompson, AM
Joseph, E
Miller, SK
AF Yorks, John E.
Thompson, Anne M.
Joseph, Everette
Miller, Sonya K.
TI The variability of free tropospheric ozone over Beltsville, Maryland
(39N, 77W) in the summers 2004-2007
SO ATMOSPHERIC ENVIRONMENT
LA English
DT Article
DE Ozone; Ozonesonde; Vertical profile; Air quality model; Boundary layer
pollution
ID UNITED-STATES; EVOLUTION; MODEL
AB Ozone profiles are often used to investigate day-to-day and year-to-year variability in origins of free tropospheric ozone. With this in mind, more than 50 ozonesonde launches were conducted in Beltsville, MD, during the summers of 2004 through 2007. Budgets of free tropospheric ozone were calculated for each ozone profile in the four summers using a laminar identification (LID) method and unusual episodes were analyzed with respect to meteorological variables. The laminar method showed that stratosphere-to-troposphere transport (ST) accounted for greater than 50% of the free tropospheric ozone column on 17% of days sampled, a more pronounced influence than regional convective and lightning (RCL) sources. The ST origins were confirmed with trajectories, and tracers (water vapor and potential vorticity). The amount of free tropospheric ozone from ST and RCL Sources varied from year-to-year (up to 13%) and can be explained by differences in mean meteorological patterns. On average, almost 30% of the free tropospheric Column was attributed to ST influence, about twice as much as RCL, although the LID method may not capture weeks-old lightning influences as in a chemical model. The prevalence of ST ozone in summertime Beltsville soundings was similar to six sounding sites in the IONS-04 campaign [Thompson, A.M., et al.. 2007b. Intercontinental Transport Experiment Ozonesonde Network Study (IONS, 2004): 1. Summertime upper tropospheric/lower stratosphere ozone over northeastern North America. J. Geophys. Res. 112, D12S12; Thompson, A.M., et al., 2007c. Intercontinental Transport Experiment Ozonesonde Network Study (IONS, 2004): 2. Tropospheric ozone budgets and variability over northeastern North America. J. Geophys. Res. 112, D12S13.] and to statistics from a 30 year climatology of European soundings [Collette, A., Ancellet, G., 2005. Impact of vertical transport processes on the tropospheric ozone layering above Europe. Part II: Climatological analysis of the past 30 years. Atmos. Environ. 39, 5423-5435]. The Beltsville record also demonstrated the value of soundings for air quality forecasting in an urban area. The 22 nighttime soundings collected over Beltsville in 2004-2007 can be divided into distinct Polluted and unpolluted Subsets, the former 20 ppbv higher in residual layer ozone (I km) than the latter. These distinctions propagated to daytime differences of 10 ppbv at the surface in the Washington, DC, area, with the high-ozone residual layers leading to non-attainment of the National Ambient Air Quality Standard for ozone. More frequent ozone observations aloft appear essential for better understanding ozone variability and for enabling air quality modelers to achieve more accurate ozone forecasts. (C) 2008 Elsevier Ltd. All rights reserved.
C1 [Yorks, John E.; Thompson, Anne M.; Miller, Sonya K.] Penn State Univ, Dept Meteorol, University Pk, PA 16802 USA.
[Joseph, Everette] Howard Univ, Dept Phys & Astron, Washington, DC 20059 USA.
RP Yorks, JE (reprint author), Sci Syst & Applicat Inc, NASA, Goddard Space Flight Ctr, Code 613-1, Greenbelt, MD USA.
EM John.E.Yorks@nasa.gov; anne@meteo.psu.edu; ejosgm@gmail.com;
smiller@meteo.psu.edu
RI Thompson, Anne /C-3649-2014
OI Thompson, Anne /0000-0002-7829-0920
FU NASA; IONS; NCAS through NOAA's Educational Partnership Program
Cooperative [NA17AF.1623]; Maryland Department of the Environment (MDE);
Goddard Space Flight Center Directors Discretionary Fund; NASA's WAVES;
MDE
FX The Upper Atmosphere Research Program of NASA, NASA's Tropospheric
Chemistry Program and Aura Validation funded this study and IONS (M. J.
Kurylo, K. W. jucks, B. G. Doddridge, J. [I. Crawford). The Beltsville
site and the Soundings are supported by NCAS through NOAA's Educational
Partnership Program Cooperative Agreement No. NA17AF.1623 and Maryland
Department of the Environment (MDE). The 2004 Soundings were funded from
the Goddard Space Flight Center Directors Discretionary Fund; supplies
in 2006 and 2007 were funded through NASA's WAVES (Water Vapor
Validation Experiment for Satellites and Soundings), and MDE. Thanks to
D. N. Whiteman (NASA/GSFC), W. F. Ryan (PSU), B.F. TaUbman (Appalachian
State), W. R. Stockwell (Howard/NCAS) and numerous Students W110
Supported ozonesonde operations at Beltsville.
NR 37
TC 20
Z9 22
U1 0
U2 7
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 APR
PY 2009
VL 43
IS 11
BP 1827
EP 1838
DI 10.1016/j.atmosenv.2008.12.049
PG 12
WC Environmental Sciences; Meteorology & Atmospheric Sciences
SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences
GA 421HF
UT WOS:000264349300001
ER
PT J
AU Han, QY
Brenguier, JL
Kuo, KS
Naeger, A
AF Han, Qingyuan
Brenguier, Jean-Louis
Kuo, Kuo-Sen
Naeger, Aaron
TI A new IR technique for monitoring low cloud properties using
geostationary satellite data
SO ATMOSPHERIC SCIENCE LETTERS
LA English
DT Article
DE low cloud; infrared; SEVIRI
ID SYSTEM
AB A new technique of using satellite infrared radiance data for retrieving cloud properties is developed and applied to SEVIRI data, which is based on direct radiative transfer calculations, not on the emissivity approximation as used by other satellite IR only techniques. Instantaneous atmospheric profiles are used in the new technique for improving the accuracy of retrievals. Comparison of the retrieved results with coincident observations of CloudSat and CALIPSO shows excellent agreement for low clouds. This study shows that, using only IR radiances, the single layer assumption would significantly underestimate cloud optical depth when multilayered cloud system is presented. Copyright (C) 2009 Royal Meteorological Society
C1 [Han, Qingyuan; Naeger, Aaron] Univ Alabama, Dept Atmospher Sci, Huntsville, AL 35899 USA.
[Brenguier, Jean-Louis] GMEI, CNRM GAME, Toulouse, France.
[Kuo, Kuo-Sen] Caelum Res Corp, Greenbelt, MD USA.
[Kuo, Kuo-Sen] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
RP Han, QY (reprint author), Univ Alabama, Dept Atmospher Sci, Huntsville, AL 35899 USA.
EM han@nsstc.uah.edu
FU Atmospheric Radiation Measurement Program; Office of Science; U.S.
Department of Energy [DE-FG02-08ER64669]
FX We thank two anonymous reviewers for their very helpful comments and
suggestions. A. Naeger is supported by the Atmospheric Radiation
Measurement Program, Office of Science, U.S. Department of Energy, Grant
No. DE-FG02-08ER64669. K. S. Kuo is supported by NASA TC4 program for
this study. Thanks for the support of Meteo-France during Q. Han's
sabbatical when the work was started. The SEVIRI data were kindly
supplied by Marcel Derrien. NCEP reanalysis data provided by the
NOAA/OAR/ESRL PSD, from URL http://www.cdc.noaa.gov are acknowledged.
NR 13
TC 2
Z9 2
U1 1
U2 5
PU WILEY-BLACKWELL
PI HOBOKEN
PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA
SN 1530-261X
J9 ATMOS SCI LETT
JI Atmos. Sci. Lett.
PD APR
PY 2009
VL 10
IS 2
BP 115
EP 121
DI 10.1002/asl.218
PG 7
WC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences
SC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences
GA 460QK
UT WOS:000267202000008
ER
PT J
AU Berry, CA
Hoffler, GW
Jernigan, CA
Kerwin, JP
Mohler, SR
AF Berry, Charles A.
Hoffler, G. Wyckliffe
Jernigan, Clarence A.
Kerwin, Joseph P.
Mohler, Stanley R.
TI History of Space Medicine: The Formative Years at NASA
SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE
LA English
DT Article
DE spaceflight; history
AB Almost nothing was known about the effects of spaceflight on human physiology when, in May of 1961, President John F. Kennedy committed the United States to land a man on the Moon and return him safely to Earth within the decade. There were more questions than answers regarding the effects of acceleration, vibration, cabin pressure, CO(2) Concentration, and microgravity. There were known external threats to life, Such as solar and ultraviolet radiation, meteorites, and extreme temperatures as well as issues for which the physicians and scientists could not even formulate the questions. And there was no time for controlled experiments with the required numbers of animal or human subjects. Of necessity, risks were evaluated and mitigated or accepted based on minimal data. This article Summarizes presentations originally giver) as a panel at the 79(th) Annual Scientific Meeting of the Aerospace Medical Association in Boston in 2008. In it, five pioneers in space medicine at NASA looked back on the development of their field. The authors related personal anecdotes, discussed the roles of various people and presented examples of contributions to emerging U.S. initiatives for human spaceflight. Topics included the development of quarantine facilities for returning Apollo astronauts, the struggles between operational medicine and research personnel, and observations from the first U.S. medical officer to experience weightlessness on orbit. Brief biographies of the authors are appended to document their participation in these historic events.
C1 [Berry, Charles A.] UTMB, Galveston, TX USA.
[Berry, Charles A.; Kerwin, Joseph P.] Lyndon B Johnson Space Ctr, Houston, TX USA.
[Berry, Charles A.] NASA Headquarters, Washington, DC USA.
[Hoffler, G. Wyckliffe] Virginia Commonwealth Univ Med Coll Virginia, Richmond, VA USA.
[Hoffler, G. Wyckliffe] Med Coll Georgia, Augusta, GA 30912 USA.
[Hoffler, G. Wyckliffe] Ohio State Univ, Columbus, OH 43210 USA.
[Hoffler, G. Wyckliffe; Jernigan, Clarence A.] NASA, Manned Spacecraft Ctr, Washington, DC USA.
[Jernigan, Clarence A.] Galveston Cty Community Hlth Serv, Galveston Cty, TX USA.
[Mohler, Stanley R.] NIH, Ctr Aging Res, Bethesda, MD 20892 USA.
[Mohler, Stanley R.] FAA Headquarters, Civil Aviat Med Res Inst, Washington, DC USA.
[Mohler, Stanley R.] FAA Headquarters, Aeromed Applicat Div, Washington, DC USA.
[Mohler, Stanley R.] Wright State Univ, Aerosp Med Residency Program, Dayton, OH 45435 USA.
FU Space Medicine Association
FX This panel was sponsored by the Space Medicine Association, a
constituent organization of the AsMA. This summary was edited by E. A.
Bopp. The Space Medicine Association intends this to be the first of an
annual series of panels on Space Medicine History.
NR 0
TC 3
Z9 4
U1 1
U2 7
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 APR
PY 2009
VL 80
IS 4
BP 345
EP 352
DI 10.3357/ASEM.2463.2009
PG 8
WC Public, Environmental & Occupational Health; Medicine, General &
Internal; Sport Sciences
SC Public, Environmental & Occupational Health; General & Internal
Medicine; Sport Sciences
GA 427LL
UT WOS:000264780700001
PM 19378903
ER
PT J
AU Kamine, TH
Bendrick, GA
AF Kamine, Tovy Haber
Bendrick, Gregg A.
TI Visual Display Angles of Conventional and a Remotely Piloted Aircraft
SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE
LA English
DT Article
DE remotely piloted aircraft; display separation; human factors; instrument
panel; information access cost; uninhabited aerial vehicle
ID OPERATIONS
AB Introduction: Instrument display separation and proximity are important human factor elements used in the design and grouping of aircraft instrument displays. To assess display proximity in practical operations, the viewing visual angles of various displays in several conventional aircraft and in a remotely piloted vehicle were assessed. Methods: The horizontal and vertical instrument display visual angles from the pilot's eye position were measured in 12 different types of conventional aircraft, and in the ground control station (GCS) of a remotely piloted air craft (RPA). A total of 18 categories of instrument display were measured and compared. Results: In conventional aircraft almost all of the vertical and horizontal visual display angles lay within a "cone of easy eye movement" (CEEM). Mission-critical instruments particular to specific aircraft types sometimes displaced less important instruments outside the CEEM. For the RPA, all horizontal visual angles lay within the CEEM, but most vertical visual angles lay Outside this cone. Discussion: Most instrument displays in conventional aircraft were consistent with display proximity principles, but several RPA displays lay outside the CEEM in the vertical plane. Awareness of this fact by RPA operators may be helpful in minimizing information access cost, and in optimizing RPA operations.
C1 Univ Penn, Sch Med, Philadelphia, PA 19104 USA.
NASA, Dryden Flight Res Ctr, Edwards AFB, CA USA.
RP Kamine, TH (reprint author), 523 W 6th St,Ste 546, Los Angeles, CA 90014 USA.
EM tovy.kamine@gmail.com
NR 19
TC 0
Z9 0
U1 1
U2 4
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 APR
PY 2009
VL 80
IS 4
BP 409
EP 413
DI 10.3357/ASEM.2337.2009
PG 5
WC Public, Environmental & Occupational Health; Medicine, General &
Internal; Sport Sciences
SC Public, Environmental & Occupational Health; General & Internal
Medicine; Sport Sciences
GA 427LL
UT WOS:000264780700013
PM 19378915
ER
PT J
AU Tao, WK
Chern, JD
Atlas, R
Randall, D
Khairoutdinov, M
Li, JL
Waliser, DE
Hou, A
Lin, X
Peters-Lidard, C
Lau, W
Jiang, J
Simpson, J
AF Tao, Wei-Kuo
Chern, Jiun-Dar
Atlas, Robert
Randall, David
Khairoutdinov, Marat
Li, Jui-Lin
Waliser, Duane E.
Hou, Arthur
Lin, Xin
Peters-Lidard, Christa
Lau, William
Jiang, Jonathan
Simpson, Joanne
TI A MULTISCALE MODELING SYSTEM Developments, Applications, and Critical
Issues
SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY
LA English
DT Article
ID CLOUD-RESOLVING MODEL; CONVECTION PARAMETERIZATION CRCP; COMMUNITY
CLIMATE MODEL; MEASURING MISSION TRMM; DIURNAL CYCLE; SINGLE-COLUMN;
NUMERICAL-SIMULATION; MESOSCALE PROCESSES; MOMENTUM TRANSPORT;
HYDROLOGIC-CYCLE
AB A multiscale modeling framework (MMF), which replaces the conventional cloud parameterizations with a cloud-resolving model (CRM) in each grid column of a GCM, constitutes a new and promising approach for climate modeling. The MMF can provide for global coverage and two-way interactions between the CRMs and their parent GCM. The CRM allows for explicit simulation of cloud processes and their interactions with radiation and surface processes, and the GCM allows for global coverage.
A new MMF has been developed that is based on the NASA Goddard Space Flight Center (GSFC) finite-volume GCM (fvGCM) and the Goddard Cumulus Ensemble (GCE) model. This Goddard MMF produces many features that are similar to another MMF that was developed at Colorado State University (CSU), such as an improved surface precipitation pattern, better cloudiness, improved diurnal variability over both oceans and continents, and a stronger propagating Madden-Julian oscillation (MJO) compared to their parent GCMs using traditional cloud parameterizations. Both MMFs also produce a large and positive precipitation bias in the Indian Ocean and western Pacific during the Northern Hemisphere summer. However, there are also notable differences between the two MMFs. For example, the CSU MMF simulates less rainfall over land than its parent GCM. This is why the CSU MMF simulated less overall global rainfall than its parent GCM. The Goddard MMF simulates more global rainfall than its parent GCM because of the high contribution from the oceanic component. A number of critical issues (i.e., the CRM's physical processes and its configuration) involving the Goddard MMF are discussed in this paper.
C1 [Tao, Wei-Kuo; Chern, Jiun-Dar; Lau, William; Simpson, Joanne] NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA.
[Chern, Jiun-Dar; Lin, Xin] Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA.
[Atlas, Robert] NOAA Atlantic Oceanog & Meteorol Lab, Miami, FL USA.
[Khairoutdinov, Marat] Colorado State Univ, Dept Atmospher Sci, Ft Collins, CO 80523 USA.
[Li, Jui-Lin; Waliser, Duane E.; Jiang, Jonathan] CALTECH, Jet Prop Lab, Pasadena, CA USA.
[Hou, Arthur; Lin, Xin] NASA, Goddard Space Flight Ctr, Global Modeling & Assimilat Off, Greenbelt, MD 20771 USA.
[Peters-Lidard, Christa] NASA, Goddard Space Flight Ctr, Hydrol Sci Branch, Greenbelt, MD 20771 USA.
RP Tao, WK (reprint author), NASA, Goddard Space Flight Ctr, Atmospheres Lab, Code 613-1, Greenbelt, MD 20771 USA.
EM Wei-Kuo.Tao-I@nasa.gov
RI Atlas, Robert/A-5963-2011; Randall, David/E-6113-2011; Hou,
Arthur/D-8578-2012; Peters-Lidard, Christa/E-1429-2012; Lau, William
/E-1510-2012
OI Atlas, Robert/0000-0002-0706-3560; Randall, David/0000-0001-6935-4112;
Peters-Lidard, Christa/0000-0003-1255-2876; Lau, William
/0000-0002-3587-3691
NR 84
TC 65
Z9 65
U1 0
U2 16
PU AMER METEOROLOGICAL SOC
PI BOSTON
PA 45 BEACON ST, BOSTON, MA 02108-3693 USA
SN 0003-0007
EI 1520-0477
J9 B AM METEOROL SOC
JI Bull. Amer. Meteorol. Soc.
PD APR
PY 2009
VL 90
IS 4
BP 515
EP +
DI 10.1175/2008BAMS2542.1
PG 21
WC Meteorology & Atmospheric Sciences
SC Meteorology & Atmospheric Sciences
GA 445FI
UT WOS:000266035100010
ER
PT J
AU Nelson, R
Boudreau, J
Gregoire, TG
Margolis, H
Naesset, E
Gobakken, T
Stahl, G
AF Nelson, Ross
Boudreau, Jonathan
Gregoire, Timothy G.
Margolis, Hank
Naesset, Erik
Gobakken, Terje
Stahl, Goran
TI Estimating Quebec provincial forest resources using ICESat/GLAS
SO CANADIAN JOURNAL OF FOREST RESEARCH-REVUE CANADIENNE DE RECHERCHE
FORESTIERE
LA English
DT Article
ID BRAZILIAN AMAZON; CARBON SINK; BIOMASS; LASER; AIRBORNE; DEFORESTATION;
INVENTORY; REGROWTH
AB Ground plots, airborne profiling and space lidar (light detection and ranging) measurements of canopy height and crown closure, space radar topographic data, a Landsat cover type map, and a vegetation zone map were used in a model-assisted, two-phase sampling design to estimate the aboveground biomass and carbon resources of Quebec. It was determined that a simple random sampling estimator, with covariance terms added, could be used to quantify the variability of regional Geoscience Laser Altimeter System (GLAS) biomass estimates where interorbit distances are, on average, 15 km apart. Prediction error increased standard errors, on average, 24.4%, 4.6%, and 2.8% at the cover type, vegetation zone, and provincial levels, respectively. Inclusion of the covariance term in the calculation of grouped cover type variances increased the vegetation zone standard errors up to 3.7 times and the provincial standard errors 15.6 times. In the southern commercial forests of Quebec, GLAS underestimated ground-based biomass values by 7.3% (stratified linear model) and 10.2% (nonstratified linear model). Quebec forests support 2.57 +/- 0.33 gigatonnes of carbon (nonstratified linear model). Approximately 25% of that carbon was found to be located in two southern vegetation zones (northern hardwood and mixedwood), another 25% in two northern vegetation zones (taiga and treed tundra), and the remaining 50% in the boreal zone.
C1 [Nelson, Ross] NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Greenbelt, MD 20771 USA.
[Boudreau, Jonathan] Univ Laval, CEF, Dept Sci Bois & Foret, Quebec City, PQ G1K 7P4, Canada.
[Gregoire, Timothy G.] Yale Univ, Sch Forestry & Environm Studies, New Haven, CT 06511 USA.
[Margolis, Hank] Univ Laval, Fac Foresterie & Geomat, CEF, Ste Foy, PQ G1K 7P4, Canada.
[Naesset, Erik; Gobakken, Terje] Norwegian Univ Life Sci, Dept Ecol & Nat Resource Management, NO-1432 As, Norway.
[Stahl, Goran] Swedish Univ Agr Sci, Dept Forest Resource Management & Geomat, S-90183 Umea, Sweden.
RP Nelson, R (reprint author), NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Code 614-4, Greenbelt, MD 20771 USA.
EM Ross.F.Nelson@nasa.gov
NR 38
TC 35
Z9 37
U1 1
U2 12
PU CANADIAN SCIENCE PUBLISHING, NRC RESEARCH PRESS
PI OTTAWA
PA 1200 MONTREAL ROAD, BUILDING M-55, OTTAWA, ON K1A 0R6, CANADA
SN 0045-5067
EI 1208-6037
J9 CAN J FOREST RES
JI Can. J. For. Res.-Rev. Can. Rech. For.
PD APR
PY 2009
VL 39
IS 4
BP 862
EP 881
DI 10.1139/X09-002
PG 20
WC Forestry
SC Forestry
GA 468IJ
UT WOS:000267810400016
ER
PT J
AU Middleton, EM
Cheng, YB
Hilker, T
Black, TA
Krishnan, P
Coops, NC
Huemmrich, KF
AF Middleton, Elizabeth M.
Cheng, Yen-Ben
Hilker, Thomas
Black, T. Andrew
Krishnan, Praveena
Coops, Nicholas C.
Huemmrich, Karl Fred
TI Linking foliage spectral responses to canopy-level ecosystem
photosynthetic light-use efficiency at a Douglas-fir forest in Canada
SO CANADIAN JOURNAL OF REMOTE SENSING
LA English
DT Review
ID PHOTOCHEMICAL REFLECTANCE INDEX; RADIATION-USE-EFFICIENCY; GROSS PRIMARY
PRODUCTION; BOREAL ASPEN FOREST; THERMAL-ENERGY DISSIPATION; EDDY
COVARIANCE TECHNIQUE; NET PRIMARY PRODUCTION; CARBON-DIOXIDE FLUXES;
LEAF-AREA INDEX; CHLOROPHYLL FLUORESCENCE
AB The light-use efficiency (LUE) of a mature Canadian Douglas-fir forest (DF49) was studied using high-resolution in situ temporal, spatial, and spectral measurements in conjunction with fluxes acquired from an instrumented tower. We examined the photochemical reflectance index (PRI), a spectral index responsive to high light conditions that alters reflectance at 531 nm, in combination with several alternative reference bands at 551, 570, and 488 nm. These indices were derived from directional reflectance spectra acquired by a hyperspectral radiometer system mounted on the DF49 tower, viewing the canopy through almost 360 rotations multiple times an hour daily throughout the 2006 growing season. From canopy structure information, three foliage sectors within the canopy were delineated according to instantaneous illumination conditions (sunlit, shaded, and mixed shaded-sunlit). On sunny days, the PRI indices for the sunlit foliage sector captured high light-induced stress responses, expressed as significantly different PRI values for sunlit versus shaded foliage. This difference was not observed on highly diffuse or overcast days. PRIs on sunny days tracked the diurnal photoregulation responses throughout the growing season in concert with illumination intensity. We computed the effective instantaneous LUE for the three foliage groups (LUEfoliage) using modeled and measured information. We provide convincing evidence that LUEfoliage can be well described and strongly related to all variations of the PRI within this coniferous forest under relatively clear skies (0.59 > r(2) > 0.80, P < 0.0001). LUEfoliage varied through the growing season between 0.015 and 0.075 mu mol C mu mol(-1) absorbed photosynthetically active radiation (APAR), and the lowest daily values were associated with the sunlit foliage group. The mixed sunlit-shaded foliage was the only group to exhibit monthly averages close to the maximum ecosystem LUE parameter (epsilon(max)) used in LUE models for evergreen needle forests (0.0196 mu mol C mu mol(-1) APAR). Implications for remote sensing of carbon uptake dynamics and the interaction of canopy structure and physiology are discussed.
C1 [Middleton, Elizabeth M.; Cheng, Yen-Ben] NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Greenbelt, MD 20771 USA.
[Hilker, Thomas; Coops, Nicholas C.] Univ British Columbia, Fac Forest Resources Management, Vancouver, BC V6T 1Z4, Canada.
[Black, T. Andrew; Krishnan, Praveena] Univ British Columbia, Fac Land & Food Syst, Vancouver, BC V6T 1Z4, Canada.
[Krishnan, Praveena] Natl Ocean & Atmospher Adm, Atmospher Turbulence & Diffus Div, Oak Ridge, TN 37830 USA.
[Huemmrich, Karl Fred] Univ Maryland, Joint Ctr Earth Syst Technol, Catonsville, MD 21228 USA.
RP Middleton, EM (reprint author), NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Greenbelt, MD 20771 USA.
EM Elizabeth.M.Middleton@nasa.gov
RI Krishnan, Praveena/F-8169-2010; Cheng, Yen-Ben/G-1311-2012; Coops,
Nicholas/J-1543-2012
OI Coops, Nicholas/0000-0002-0151-9037
FU National Aeronautics and Space Administration (NASA); German Academic
Exchange Service (DAAD); Natural Sciences and Engineering Research
Council of Canada (NSERC)
FX This research was supported by National Aeronautics and Space
Administration (NASA) Research Opportunities in Space and Earth Sciences
(ROSES) funding through the Carbon Cycle Science Program (Diane
Wickland, Manager). Yen-Ben Cheng was supported through the NASA
Postdoctoral Program, administered by Oak Ridge Associated Universities.
Thomas Hilker was partially funded by a postgraduate scholarship of the
German Academic Exchange Service (DAAD), a Natural Sciences and
Engineering Research Council of Canada (NSERC) Discovery Grant to
Nicholas Coops, and funds provided to the University of British Columbia
(UBC) from the Comprehensive Community Plan (CCP), NSERC, and BIOCAP. We
acknowledge the following people for their assistance in technical
design, installation, and maintenance of the radiometer platform: Zoran
Nesic, Dominic Lessard, Rick Ketler, and Andrew Sauter from UBC Faculty
of Land and Food Systems (LFS).
NR 116
TC 47
Z9 47
U1 1
U2 22
PU CANADIAN AERONAUTICS SPACE INST
PI KANATA
PA 350 TERRY FOX DR, STE 104, KANATA, ON K2K 2W5, CANADA
SN 1712-7971
J9 CAN J REMOTE SENS
JI Can. J. Remote Sens.
PD APR
PY 2009
VL 35
IS 2
BP 166
EP 188
PG 23
WC Remote Sensing
SC Remote Sensing
GA 455BC
UT WOS:000266729300007
ER
PT J
AU Pitjeva, EV
Standish, EM
AF Pitjeva, E. V.
Standish, E. M.
TI Proposals for the masses of the three largest asteroids, the Moon-Earth
mass ratio and the Astronomical Unit
SO CELESTIAL MECHANICS & DYNAMICAL ASTRONOMY
LA English
DT Article
DE Ceres mass; DE ephemerides; EPM ephemerides; Pallas mass; Vesta mass;
Moon-Earth mass ratio; Astronomical Unit
ID 1 CERES; 4 VESTA; EPHEMERIS; PERTURBATIONS; PALLAS; MARS
AB We propose to the NSFA (the IAU Working Group on Numerical Standards for Fundamental Astronomy) the following representative values and realistic uncertainties for the masses of the three largest asteroids (Ceres, Pallas, Vesta), to be used as the current best estimates:
M(Cres)/M(circle dot) = 4.72 . 10(-10),
M(Pallas)/M(circle dot) = 1.03 . 10(-10),
M(Vesta)/M(circle dot) = 1.35 . 10(-10).
Unlike the values previously adopted in the Astronomical Almanac, these are consistent with nearly all of the twenty or so modern accurate determinations from various authors. We also have proposed the following values for the Moon-Earth mass ratio and the astronomical unit in meters obtained from the ephemeris improvement processes at JPL in Pasadena and at IAA RAS in St.Petersburg: M(Moon)/M(Earth) = 0.0123000371(4) and AU = 149597870700(3) m. The numerical value of the AU in meters is identical in both the TDB-based and the TCB-based systems of units if one uses the conversion proposed by Irwin and Fukushima, Brumberg and Groten, Brumberg and Simon.
C1 [Pitjeva, E. V.] Russian Acad Sci, Inst Appl Astron, St Petersburg 191187, Russia.
[Standish, E. M.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
RP Pitjeva, EV (reprint author), Russian Acad Sci, Inst Appl Astron, Kutuzov Quay 10, St Petersburg 191187, Russia.
EM evp@ipa.nw.ru; ems@jpl.nasa.gov
FU Institute of Applied Astronomy of Russian Academy of Sciences; Jet
Propulsion Laboratory, California Institute of Technology
FX The work described in this paper was carried out at the Institute of
Applied Astronomy of Russian Academy of Sciences and at the Jet
Propulsion Laboratory, California Institute of Technology, under
contract with the National Aeronautics and Space Administration.
NR 35
TC 32
Z9 35
U1 0
U2 3
PU SPRINGER
PI DORDRECHT
PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS
SN 0923-2958
J9 CELEST MECH DYN ASTR
JI Celest. Mech. Dyn. Astron.
PD APR
PY 2009
VL 103
IS 4
BP 365
EP 372
DI 10.1007/s10569-009-9203-8
PG 8
WC Astronomy & Astrophysics; Mathematics, Interdisciplinary Applications
SC Astronomy & Astrophysics; Mathematics
GA 431BP
UT WOS:000265036600005
ER
PT J
AU Pavlick, MM
Johnson, WS
Jensen, B
Weiser, E
AF Pavlick, M. M.
Johnson, W. S.
Jensen, Brian
Weiser, Erik
TI Evaluation of mechanical properties of advanced polymers for composite
cryotank applications
SO COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
LA English
DT Article
DE Polymers; Fracture toughness; Strength; Mechanical testing
AB Composite materials are actively being used in the aerospace industry as a means of reducing weight. In particular, polymer matrix composites (PMC) are good candidates due to their high strength-to-weight and stiffness-to-weight ratios. A fundamental step to understand how a PMC will behave in a cryotank's extreme environmental is to first understand how the constituents (namely, the polymer matrix) behave in that same environment. Therefore, both stress-based and fracture-based experiments were conducted to evaluate four candidate polymers supplied by NASA Langley Research Center. Each type of test was conducted at approximately -196 degrees C (-320 degrees F), 24 degrees C (76 degrees F), and 160 degrees C (320 degrees F). Based on the results of the four polymer systems, a recommendation as to the best candidate for polymer matrix and adhesive bonding for Reusable Launch Vehicle's (RLV's) composite cryotanks is made. (C) 2009 Elsevier Ltd. All rights reserved.
C1 [Johnson, W. S.] Georgia Inst Technol, Sch Mat Sci & Engn, Atlanta, GA 30332 USA.
[Pavlick, M. M.; Johnson, W. S.] Georgia Inst Technol, George W Woodruff Sch Mech Engn, Atlanta, GA 30332 USA.
[Jensen, Brian; Weiser, Erik] NASA LaRC, Adv Mat & Proc Branch, Hampton, VA 23662 USA.
RP Johnson, WS (reprint author), Georgia Inst Technol, Sch Mat Sci & Engn, Atlanta, GA 30332 USA.
EM steve.johnson@mse.gatech.edu
FU NASA Langley Research Center in Hampton, VA under NASA [NAG-1-02003]
FX This research was sponsored by NASA Langley Research Center in Hampton,
VA under NASA Grant NAG-1-02003. The authors thank Dr. C.P. Wong
(MSE/Georgia Tech) for his time invested during TMA analysis.
NR 12
TC 5
Z9 5
U1 1
U2 4
PU ELSEVIER SCI LTD
PI OXFORD
PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND
SN 1359-835X
J9 COMPOS PART A-APPL S
JI Compos. Pt. A-Appl. Sci. Manuf.
PD APR
PY 2009
VL 40
IS 4
BP 359
EP 367
DI 10.1016/j.compositesa.2008.12.009
PG 9
WC Engineering, Manufacturing; Materials Science, Composites
SC Engineering; Materials Science
GA 437BD
UT WOS:000265459800006
ER
PT J
AU Narock, TW
Szabo, A
Merka, J
AF Narock, T. W.
Szabo, A.
Merka, J.
TI Using semantics to extend the space physics data environment
SO COMPUTERS & GEOSCIENCES
LA English
DT Article; Proceedings Paper
CT Fall Meeting of the American-Geophysical-Union
CY DEC, 2006
CL San Francisco, CA
SP Amer Geophys Union
DE Virtual observatory; Ontology; Registry; Search and retrieval; Data
processing; Web services
AB The space physics data environment is evolving with the advent of virtual observatories. With the primary function of most virtual observatories being data search and retrieval, an emphasis has been placed on providing value-added data processing services. That is, creating web services that take discovered data and provide common and routine processing such as coordinate transformations and data sub-setting. As these services proliferate, finding, accessing and using them no longer becomes a trivial task. This paper discusses a semantic registry that enables the searching of these services via ontology. We discuss the benefits of such a registry and illustrate how the web and application programming interfaces benefit the space physics community. (C) 2008 Elsevier Ltd. All rights reserved.
C1 [Narock, T. W.; Merka, J.] Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21250 USA.
[Narock, T. W.; Szabo, A.; Merka, J.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
RP Narock, TW (reprint author), Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, 1000 Hilltop Circle, Baltimore, MD 21250 USA.
EM Thomas.W.Narock@nasa.gov
OI Narock, Tom/0000-0002-9785-4496
NR 10
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 0098-3004
J9 COMPUT GEOSCI-UK
JI Comput. Geosci.
PD APR
PY 2009
VL 35
IS 4
BP 791
EP 797
DI 10.1016/j.cageo.2007.12.010
PG 7
WC Computer Science, Interdisciplinary Applications; Geosciences,
Multidisciplinary
SC Computer Science; Geology
GA 437GS
UT WOS:000265475500011
ER
PT J
AU Nieves-Chinchilla, T
Vinas, AF
Hidalgo, M
AF Nieves-Chinchilla, T.
Vinas, A. -F.
Hidalgo, M. A.
TI Magnetic Field Profiles Within Magnetic Clouds: A Model-Approach
SO EARTH MOON AND PLANETS
LA English
DT Article; Proceedings Paper
CT European General Assembly on International Heliophysics Year
CY JUN, 2007
CL Torino, ITALY
DE Magnetic cloud; The cross-section distortion and expansion
ID CROSS-SECTION; TOPOLOGY; WIND
AB The model of Hidalgo (J. Geophys. Res. 108(A8):1320, 2003) has meant one more step in the understanding of the magnetic cloud events. We have modified a physical assumption over the y-components of the current density, have developed an algorithm which is able to resolve the elliptic integrals and have incorporated constrains over the parameters. This article is a new contribution for the improvement of the fitting procedure.
C1 [Nieves-Chinchilla, T.; Vinas, A. -F.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
[Hidalgo, M. A.] Univ Alcala de Henares, Space Res Grp, Alcala De Henares, Spain.
RP Nieves-Chinchilla, T (reprint author), NASA, Goddard Space Flight Ctr, 8800 Greenbelt Rd,Bld 21, Greenbelt, MD 20771 USA.
EM Teresa.Nieves@nasa.gov
RI Nieves-Chinchilla, Teresa/F-3482-2016; Hidalgo, Miguel/L-5826-2014
OI Nieves-Chinchilla, Teresa/0000-0003-0565-4890; Hidalgo,
Miguel/0000-0003-1617-2037
NR 7
TC 2
Z9 2
U1 0
U2 4
PU SPRINGER
PI DORDRECHT
PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS
SN 0167-9295
EI 1573-0794
J9 EARTH MOON PLANETS
JI Earth Moon Planets
PD APR
PY 2009
VL 104
IS 1-4
BP 109
EP 113
DI 10.1007/s11038-008-9252-0
PG 5
WC Astronomy & Astrophysics; Geosciences, Multidisciplinary
SC Astronomy & Astrophysics; Geology
GA 414MX
UT WOS:000263869300024
ER
PT J
AU Verdini, A
Velli, M
Buchlin, E
AF Verdini, A.
Velli, M.
Buchlin, E.
TI Reflection Driven MHD Turbulence in the Solar Atmosphere and Wind
SO EARTH MOON AND PLANETS
LA English
DT Article; Proceedings Paper
CT European General Assembly on International Heliophysics Year
CY JUN, 2007
CL Torino, ITALY
DE MHD; Waves; Turbulence; Sun: solar wind
ID ALFVEN WAVES; LOW-FREQUENCY; SHELL-MODEL; ACCELERATION; PROPAGATION;
REGION; SUN
AB Alfv,nic turbulence is usually invoked and used in many solar wind models (Isenberg and Hollweg, 1982, J. Geophys. Res. 87:5023; Tu et al. 1984, J. Geophys. Res. 89:9695; Hu et al. 2000, J. Geophys. Res. 105:5093; Li 2003, Astron. Astrphys. 406:345; Isenberg 2004, J. Geophys. Res. 109:3101) as a process responsible for the transfer of energy, released at large scale in the photosphere, towards small scale in the corona, where it is dissipated. Usually an initial spectrum is prescribed since the closest constraint to the spectrum is given by Helios measurements at 0.3 AU. With this work we intend to study the efficiency of the reflection as a driver for the nonlinear interactions of Alfv,n waves, the development of a turbulent spectrum and its evolution in the highly stratified solar atmosphere inside coronal holes. Our main finding is that the perpendicular spectral slope changes substantially at the transition region because of the steep density gradient. As a result a strong turbulent heating occurs, just above the transition region, as requested by current solar wind models.
C1 [Verdini, A.] Royal Observ Belgium, SIDC, Brussels, Belgium.
[Verdini, A.; Velli, M.] Univ Florence, Dept Astron, Florence, Italy.
[Velli, M.] JPL, Pasadena, CA USA.
[Buchlin, E.] Univ London Imperial Coll Sci Technol & Med, London, England.
RP Verdini, A (reprint author), Royal Observ Belgium, SIDC, Brussels, Belgium.
EM verdini@oma.be
OI Buchlin, Eric/0000-0003-4290-1897
NR 16
TC 4
Z9 5
U1 0
U2 2
PU SPRINGER
PI DORDRECHT
PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS
SN 0167-9295
EI 1573-0794
J9 EARTH MOON PLANETS
JI Earth Moon Planets
PD APR
PY 2009
VL 104
IS 1-4
BP 121
EP 125
DI 10.1007/s11038-008-9250-2
PG 5
WC Astronomy & Astrophysics; Geosciences, Multidisciplinary
SC Astronomy & Astrophysics; Geology
GA 414MX
UT WOS:000263869300026
ER
PT J
AU Zimbardo, G
Greco, A
Veltri, P
Voros, Z
Amata, E
Taktakishvili, A
Carbone, V
Sorriso-Valvo, L
Guerra, I
AF Zimbardo, G.
Greco, A.
Veltri, P.
Voros, Z.
Amata, E.
Taktakishvili, A. L.
Carbone, V.
Sorriso-Valvo, L.
Guerra, I.
TI Solar-Terrestrial Relations: Magnetic Turbulence in the Earth's
Magnetosphere and Geomagnetic Activity
SO EARTH MOON AND PLANETS
LA English
DT Article; Proceedings Paper
CT European General Assembly on International Heliophysics Year
CY JUN, 2007
CL Torino, ITALY
DE Magnetic turbulence; Magnetosphere; Transport; Solar wind
ID ELECTRON WHISTLER INTERACTION; DISTANT MAGNETOTAIL; PLASMA SHEET; BOW
SHOCK; DYNAMICS
AB Recent spacecraft observations of magnetic turbulence in the ion foreshock, in the magnetosheath, in the polar cusp regions, and in the magnetotail will be reviewed. Turbulence features like the fluctuation level, the spectral power law index, the turbulence anisotropy and intermittency, and the turbulence driver will be addressed.
C1 [Zimbardo, G.; Greco, A.; Veltri, P.; Carbone, V.; Sorriso-Valvo, L.; Guerra, I.] Univ Calabria, I-87036 Cosenza, Italy.
[Voros, Z.] Inst Atmospher Res, Prague, Czech Republic.
[Amata, E.] Ist Fis Spazio Interplanetario, INAF, Rome, Italy.
[Taktakishvili, A. L.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
[Taktakishvili, A. L.] Abastumani Astrophys Observ, Tbilisi, Rep of Georgia.
RP Zimbardo, G (reprint author), Univ Calabria, I-87036 Cosenza, Italy.
EM zimbardo@fis.unical.it
RI Sorriso-Valvo, Luca/A-9355-2008; Veltri, Pierluigi/J-1348-2014;
OI Sorriso-Valvo, Luca/0000-0002-5981-7758; Veltri,
Pierluigi/0000-0002-7412-1660; Voros, Zoltan/0000-0001-7597-238X;
Zimbardo, Gaetano/0000-0002-9207-2647; CARBONE,
Vincenzo/0000-0002-3182-6679
NR 15
TC 1
Z9 1
U1 0
U2 6
PU SPRINGER
PI DORDRECHT
PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS
SN 0167-9295
J9 EARTH MOON PLANETS
JI Earth Moon Planets
PD APR
PY 2009
VL 104
IS 1-4
BP 127
EP 129
DI 10.1007/s11038-008-9251-1
PG 3
WC Astronomy & Astrophysics; Geosciences, Multidisciplinary
SC Astronomy & Astrophysics; Geology
GA 414MX
UT WOS:000263869300027
ER
PT J
AU Bettarini, L
Landi, S
Velli, M
Londrillo, P
AF Bettarini, L.
Landi, S.
Velli, M.
Londrillo, P.
TI Magnetic and Velocity Shear Driven Instabilities in the Heliospheric
Plasma
SO EARTH MOON AND PLANETS
LA English
DT Article; Proceedings Paper
CT European General Assembly on International Heliophysics Year
CY JUN, 2007
CL Torino, ITALY
DE Solar wind; Ideal and resistive instabilities Magnetic reconnection; 3D
MHD numerical simulations Introduction
AB We have addressed the problem of combined magnetic and velocity shear driven instabilities in the context of the heliospheric plasma. New high-order numerical methods have been used to analyze the instability dynamics of the heliospheric current-sheet interacting with the structure determined by the slow component of the solar wind on the solar equatorial plane above the helmet streamers. Preliminary results are presented.
C1 [Bettarini, L.; Landi, S.; Velli, M.] Univ Florence, Dipartimento Astron & Sci Spazio, I-50125 Florence, Italy.
[Velli, M.] CALTECH, Jet Prop Lab, Pasadena, CA USA.
[Londrillo, P.] INAF Osservatorio Astronom Bologna, Bologna, Italy.
RP Bettarini, L (reprint author), Univ Florence, Dipartimento Astron & Sci Spazio, I-50125 Florence, Italy.
EM lapo.bettarini@wis.kuleuven.be
RI Landi, Simone/G-7282-2015
OI Landi, Simone/0000-0002-1322-8712
NR 8
TC 0
Z9 0
U1 0
U2 1
PU SPRINGER
PI DORDRECHT
PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS
SN 0167-9295
J9 EARTH MOON PLANETS
JI Earth Moon Planets
PD APR
PY 2009
VL 104
IS 1-4
BP 135
EP 137
DI 10.1007/s11038-008-9270-y
PG 3
WC Astronomy & Astrophysics; Geosciences, Multidisciplinary
SC Astronomy & Astrophysics; Geology
GA 414MX
UT WOS:000263869300029
ER
PT J
AU Gopalswamy, N
Eichhorn, G
Sakurai, T
Haubold, H
AF Gopalswamy, N.
Eichhorn, G.
Sakurai, T.
Haubold, H. J.
TI Preface to the Proceedings of the European General Assembly and the
United Nations Workshop
SO EARTH MOON AND PLANETS
LA English
DT Editorial Material
C1 [Gopalswamy, N.; Eichhorn, G.; Sakurai, T.; Haubold, H. J.] Vienna Int Ctr, UN Off Outer Space Affairs, A-1400 Vienna, Austria.
[Gopalswamy, N.] NASA, Goddard Space Flight Ctr, Code 695, Greenbelt, MD 20771 USA.
[Eichhorn, G.] Springer, Abstracting & Indexing, Norwell, MA 02061 USA.
[Sakurai, T.] Natl Astron Observ, Tokyo 181, Japan.
RP Haubold, H (reprint author), Vienna Int Ctr, UN Off Outer Space Affairs, Wagramerstr 5,POB 500, A-1400 Vienna, Austria.
EM hans.haubold@unvienna.org
RI Eichhorn, Guenther/C-9480-2009; Gopalswamy, Nat/D-3659-2012
OI Eichhorn, Guenther/0000-0002-3032-1978;
NR 0
TC 0
Z9 0
U1 0
U2 4
PU SPRINGER
PI DORDRECHT
PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS
SN 0167-9295
J9 EARTH MOON PLANETS
JI Earth Moon Planets
PD APR
PY 2009
VL 104
IS 1-4
BP 139
EP 140
DI 10.1007/s11038-008-9278-3
PG 2
WC Astronomy & Astrophysics; Geosciences, Multidisciplinary
SC Astronomy & Astrophysics; Geology
GA 414MX
UT WOS:000263869300030
ER
PT J
AU Gopalswamy, N
Yashiro, S
Michalek, G
Stenborg, G
Vourlidas, A
Freeland, S
Howard, R
AF Gopalswamy, N.
Yashiro, S.
Michalek, G.
Stenborg, G.
Vourlidas, A.
Freeland, S.
Howard, R.
TI The SOHO/LASCO CME Catalog
SO EARTH MOON AND PLANETS
LA English
DT Article; Proceedings Paper
CT European General Assembly on International Heliophysics Year
CY JUN, 2007
CL Torino, ITALY
DE Coronal mass ejections; Flares; Geomagnetic storms; Solar energetic
particle events
ID CORONAL MASS EJECTIONS; MAGNETIC CLOUDS; RADIO; SOLAR-CYCLE-23
AB Coronal mass ejections (CMEs) are routinely identified in the images of the solar corona obtained by the Solar and Heliospheric Observatory (SOHO) mission's Large Angle and Spectrometric Coronagraph (LASCO) since 1996. The identified CMEs are measured and their basic attributes are cataloged in a data base known as the SOHO/LASCO CME Catalog. The Catalog also contains digital data, movies, and plots for each CME, so detailed scientific investigations can be performed on CMEs and the related phenomena such as flares, radio bursts, solar energetic particle events, and geomagnetic storms. This paper provides a brief description of the Catalog and summarizes the statistical properties of CMEs obtained using the Catalog. Data products relevant to space weather research and some CME issues that can be addressed using the Catalog are discussed. The URL of the Catalog is: http://cdaw.gsfc.nasa.gov/CME_list.
C1 [Yashiro, S.; Michalek, G.; Stenborg, G.] Catholic Univ Amer, Washington, DC 20064 USA.
[Vourlidas, A.; Howard, R.] USN, Res Lab, Washington, DC 20375 USA.
[Freeland, S.] Lockheed Martin Adv Technol Ctr, Palo Alto, CA USA.
[Gopalswamy, N.] NASA, Goddard Space Flight Ctr, Code 695, Greenbelt, MD 20771 USA.
RP Gopalswamy, N (reprint author), NASA, Goddard Space Flight Ctr, Code 695, Greenbelt, MD 20771 USA.
EM nat.gopalswamy@nasa.gov; seiji.yashiro@nasa.gov; freeland@lmsal.com;
russ.howard@nrl.navy.mil
RI Vourlidas, Angelos/C-8231-2009; Gopalswamy, Nat/D-3659-2012
OI Vourlidas, Angelos/0000-0002-8164-5948;
NR 33
TC 159
Z9 160
U1 1
U2 7
PU SPRINGER
PI DORDRECHT
PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS
SN 0167-9295
J9 EARTH MOON PLANETS
JI Earth Moon Planets
PD APR
PY 2009
VL 104
IS 1-4
BP 295
EP 313
DI 10.1007/s11038-008-9282-7
PG 19
WC Astronomy & Astrophysics; Geosciences, Multidisciplinary
SC Astronomy & Astrophysics; Geology
GA 414MX
UT WOS:000263869300045
ER
PT J
AU Hill, F
Martens, P
Yoshimura, K
Gurman, J
Hourcle, J
Dimitoglou, G
Suarez-Sola, I
Wampler, S
Reardon, K
Davey, A
Bogart, R
Tian, K
AF Hill, Frank
Martens, Piet
Yoshimura, Keji
Gurman, Joseph
Hourcle, Joseph
Dimitoglou, George
Suarez-Sola, Igor
Wampler, Steve
Reardon, Kevin
Davey, Alisdair
Bogart, Richard S.
Tian, Karen Q.
TI The Virtual Solar Observatory-A Resource for International Heliophysics
Research
SO EARTH MOON AND PLANETS
LA English
DT Article; Proceedings Paper
CT European General Assembly on International Heliophysics Year
CY JUN, 2007
CL Torino, ITALY
DE Data management; Virtual observatories; Solar physics; Distributed
archives
ID SYSTEM
AB The Virtual Solar Observatory (VSO) has been developed to allow researchers, educators, and the general public to access data and images from the major sources of on-line solar data. The VSO substantially reduces the effort required to locate disparate data sets, and removes the need for the user to locate the data and learn multiple interfaces. The VSO provides a single interface to about 60 geographically distributed data sets including space- and ground-based sources. These data sets incorporate several physical variables including magnetic field, intensity, Doppler velocity, etc., and all wavelengths from X-ray to radio. All layers of the sun, from the interior to the corona, are included. In this paper we describe the system and present the interface that the user will encounter. We also discuss future enhancements planned for the system.
C1 [Hill, Frank; Suarez-Sola, Igor; Wampler, Steve] Natl Solar Observ, Tucson, AZ 85719 USA.
[Martens, Piet; Yoshimura, Keji] Montana State Univ, Bozeman, MT 59717 USA.
[Gurman, Joseph; Hourcle, Joseph; Dimitoglou, George] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
[Reardon, Kevin] Osservatorio Arcetri, Florence, Italy.
[Davey, Alisdair] SW Res Inst, Boulder, CO USA.
[Bogart, Richard S.; Tian, Karen Q.] Stanford Univ, Stanford, CA 94305 USA.
RP Hill, F (reprint author), Natl Solar Observ, 950 N Cherry Ave, Tucson, AZ 85719 USA.
EM fhill@noao.edu
OI Hourcle, Joe/0000-0002-0713-594X
NR 10
TC 5
Z9 5
U1 0
U2 1
PU SPRINGER
PI DORDRECHT
PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS
SN 0167-9295
EI 1573-0794
J9 EARTH MOON PLANETS
JI Earth Moon Planets
PD APR
PY 2009
VL 104
IS 1-4
BP 315
EP 330
DI 10.1007/s11038-008-9274-7
PG 16
WC Astronomy & Astrophysics; Geosciences, Multidisciplinary
SC Astronomy & Astrophysics; Geology
GA 414MX
UT WOS:000263869300046
ER
PT J
AU Lee, JSF
Berejikian, BA
AF Lee, Jonathan S. F.
Berejikian, Barry A.
TI Structural complexity in relation to the habitat preferences,
territoriality, and hatchery rearing of juvenile China rockfish
(Sebastes nebulosus)
SO ENVIRONMENTAL BIOLOGY OF FISHES
LA English
DT Article
DE Stock enhancement; Conservation hatchery; Predation risk; Rearing
effects
ID CORAL-REEF FISH; BODY-SIZE; DOMINANCE; SETTLEMENT; ECOLOGY; COMMUNITIES;
SURVIVAL; BEHAVIOR; GROWTH; SALMON
AB Conservation efforts require an understanding of the basic behavior and ecology of target species. However, limited information exists for a wide range of taxa, including declining species of rockfish (genus Sebastes). First, we observed captive juvenile China rockfish (S. nebulosus) to determine how they interact with their environment and conspecifics. Juveniles exhibited site fidelity and territoriality. These aggressive interactions occurred within the context of size-biased dominance, centered on competition for structurally complex habitat. Given the apparent importance of structure and the absence of structure in typical hatchery environments, we then asked how the absence of structure affects future behavior. When barren-reared and structure-reared juveniles were combined into a structurally complex aquarium, barren-reared fish displayed less structure use and less site fidelity than structure-reared fish. However, after 1 to 2 weeks, barren-reared fish began to use structure and showed site fidelity that eventually equaled that of structure-reared juveniles, showing that those behavioral effects of the rearing environment were not permanent. Though these short-term effects may still impact survival after hatchery release, we were unable to detect significant effects on vulnerability to a predator (lingcod, Ophiodon elongatus) in laboratory trials.
C1 [Lee, Jonathan S. F.; Berejikian, Barry A.] NW Fisheries Sci Ctr, Manchester Res Stn, Natl Marine Fisheries Serv, Resource Enhancement & Utilizat Technol Div, Manchester, WA 98353 USA.
RP Lee, JSF (reprint author), NW Fisheries Sci Ctr, Manchester Res Stn, Natl Marine Fisheries Serv, Resource Enhancement & Utilizat Technol Div, POB 130, Manchester, WA 98353 USA.
EM jon.lee@noaa.gov
RI Bizzarro, Joseph/A-2988-2012
FU NOAA Fisheries; Science Consortium for Ocean Replenishment (SCORE)
FX We thank Ken Massee (National Oceanic and Atmospheric
Administration-NOAA), Mike Rust (NOAA), Tom Waite (University of Idaho),
and the Seattle Aquarium for providing the juvenile China rockfish. We
also appreciate help from Jeff Atkins in preparing the flume and
aquaria, and Tom Flagg and Walt Dickhoff for reviewing the manuscript.
This study was funded by a NOAA Fisheries funded research consortium -
the Science Consortium for Ocean Replenishment (SCORE). The views
expressed are those of the authors and do not necessarily reflect those
of the funding agency.
NR 31
TC 4
Z9 4
U1 3
U2 12
PU SPRINGER
PI NEW YORK
PA 233 SPRING ST, NEW YORK, NY 10013 USA
SN 0378-1909
J9 ENVIRON BIOL FISH
JI Environ. Biol. Fishes
PD APR
PY 2009
VL 84
IS 4
BP 411
EP 419
DI 10.1007/s10641-009-9450-2
PG 9
WC Ecology; Marine & Freshwater Biology
SC Environmental Sciences & Ecology; Marine & Freshwater Biology
GA 420BG
UT WOS:000264262800011
ER
PT J
AU Ross, KW
Brown, ME
Verdin, JP
Underwood, LW
AF Ross, K. W.
Brown, M. E.
Verdin, J. P.
Underwood, L. W.
TI Review of FEWS NET biophysical monitoring requirements
SO ENVIRONMENTAL RESEARCH LETTERS
LA English
DT Review
DE applied remote sensing; requirements definition; Earth observations;
early warning
ID SPOT-VEGETATION; MODIS; RAINFALL; AFRICA; AVHRR
AB The Famine Early Warning System Network (FEWS NET) provides monitoring and early warning support to decision makers responsible for responding to famine and food insecurity. FEWS NET transforms satellite remote sensing data into rainfall and vegetation information that can be used by these decision makers. The National Aeronautics and Space Administration has recently funded activities to enhance remote sensing inputs to FEWS NET. To elicit Earth observation requirements, a professional review questionnaire was disseminated to FEWS NET expert end-users; it focused upon operational requirements to determine additional useful remote sensing data and, subsequently, to assess whether such data would be beneficial as FEWS NET biophysical supplementary inputs. The review was completed by over 40 experts from around the world. Reviewers were asked to evaluate the relative importance of environmental variables and spatio-temporal requirements for Earth science data products, in particular for rainfall and vegetation products. The results showed that spatio-temporal resolution requirements are complex and need to vary according to place, time, and hazard; that high resolution remote sensing products continue to be in demand; and that rainfall and vegetation products are valued as data that provide actionable food security information.
C1 [Ross, K. W.; Underwood, L. W.] Sci Syst & Applicat Inc, Poplarville, MS 39470 USA.
[Brown, M. E.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
[Verdin, J. P.] NOAA, ESRL, US Geol Survey, Boulder, CO 80305 USA.
RP Ross, KW (reprint author), Sci Syst & Applicat Inc, 411 W Michigan St, Poplarville, MS 39470 USA.
EM kenton_ross@ssaihq.com; molly.brown@nasa.gov; verdin@usgs.gov;
lauren_underwood@ssaihq.com
RI Brown, Molly/E-2724-2010; Brown, Molly/M-5146-2013;
OI Brown, Molly/0000-0001-7384-3314; Brown, Molly/0000-0001-7384-3314;
Ross, Kenton/0000-0002-6381-5894
FU NASA [NNS06AA60I, NNG06HU01G]
FX The USGS directs this work with funding provided through NASA
Interagency Purchase Request NNS06AA60I. K Ross, M Brown, and L
Underwood participate under NASA Grant NNG06HU01G.
NR 17
TC 5
Z9 5
U1 1
U2 5
PU IOP PUBLISHING LTD
PI BRISTOL
PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND
SN 1748-9326
J9 ENVIRON RES LETT
JI Environ. Res. Lett.
PD APR-JUN
PY 2009
VL 4
IS 2
AR 024009
DI 10.1088/1748-9326/4/2/024009
PG 10
WC Environmental Sciences; Meteorology & Atmospheric Sciences
SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences
GA 470QD
UT WOS:000267991900010
ER
PT J
AU Priester, JH
Stoimenov, PK
Mielke, RE
Webb, SM
Ehrhardt, C
Zhang, JP
Stucky, GD
Holden, PA
AF Priester, John H.
Stoimenov, Peter K.
Mielke, Randall E.
Webb, Samuel M.
Ehrhardt, Christopher
Zhang, Jin Ping
Stucky, Galen D.
Holden, Patricia A.
TI Effects of Soluble Cadmium Salts Versus CdSe Quantum Dots on the Growth
of Planktonic Pseudomonas aeruginosa
SO ENVIRONMENTAL SCIENCE & TECHNOLOGY
LA English
DT Article
ID ESCHERICHIA-COLI; OXIDATIVE STRESS; ANTIMICROBIAL ACTIVITY; SILVER
NANOPARTICLES; UNSATURATED BIOFILMS; CYTOTOXICITY; BACTERIA; MECHANISMS;
COMMUNITY; TOXICITY
AB With their increased use, engineered nanomaterials (ENMs) will enter the environment where they maybe altered by bacteria and affect bacterial processes. Metallic ENMs, such as CdSe quantum dots (QDs), are toxic due to the release of dissolved heavy metals, but the effects of cadmium ions versus intact QDs are mostly unknown. Here, planktonic Pseudomonas aeruginosa PG201 bacteria were cultured with similar total cadmium concentrations as either fully dissolved cadmium acetate (Cd(CH3COO)(2)) or ligand capped CdSe QDs, and cellular morphology, growth parameters, intracellular reactive oxygen species (ROS), along with the metal and metalloid fates were measured. QDs dissolved partially in growth media, but dissolution was less in biotic cultures compared to sterile controls. Dose-dependent growth effects were similar for low concentrations of either cadmium salts or QDs, but effects differed above a concentration threshold of 50 mg/L(total cadmium basis) where (1) the growth of QD-treated cells was more impaired, (2) the membranes of QD-grown cells were damaged, and (3) CID-grown cells contained QD-sized CdSe cytoplasmic inclusions in addition to Se-0 and dissolved cadmium. For most concentrations, intracellular ROS were higher for QD-versus cadmium salts-grown bacteria. Taken together, QDs were more toxic to this opportunistic pathogen than cadmium ions, and were affected by cells through QD extracellular stabilization, intracellular enrichment, and cell-associated decay.
C1 [Priester, John H.; Holden, Patricia A.] Univ Calif Santa Barbara, Donald Bren Sch Environm Sci & Management, Santa Barbara, CA 93106 USA.
[Stoimenov, Peter K.; Stucky, Galen D.] Univ Calif Santa Barbara, Dept Chem & Biochem, Santa Barbara, CA 93106 USA.
[Mielke, Randall E.] CALTECH, Jet Prop Lab, Ctr Life Detect, Pasadena, CA 91109 USA.
[Webb, Samuel M.] Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Menlo Pk, CA 94025 USA.
RP Holden, PA (reprint author), Univ Calif Santa Barbara, Donald Bren Sch Environm Sci & Management, Santa Barbara, CA 93106 USA.
EM holden@bren.ucsb.edu
RI Webb, Samuel/D-4778-2009;
OI Webb, Samuel/0000-0003-1188-0464; Ehrhardt,
Christopher/0000-0002-4909-0532
FU U.S. EPA STAR [R831712, R833323]; University of California Toxic
Substances Research and Training Program; Office of Science (BER), U.S.
Department of Energy [DE-FG02-05ER63949]; National Science Foundation
[DMR05-20415]; Environmental Protection Agency [EF 0830117]
FX This research was supported by the U.S. EPA STAR Awards R831712 and
R833323, by the University of California Toxic Substances Research and
Training Program: Lead Campus program in Nanotoxicology, and by the
Office of Science (BER), U.S. Department of Energy, Grant
DE-FG02-05ER63949. Publication of this material is Supported by the
National Science Foundation and the Environmental Protection Agency
under Cooperative Agreement EF 0830117. Any opinions, findings, and
conclusions or recommendations expressed in this material are those of
the author(s) and do not necessarily reflect the views of the National
Science Foundation or the Environmental Protection Agency. This work has
not been subjected to EPA review and no official endorsement should be
infer-red. This work made use of UCSB MRL Central Facilities supported
by the MRSEC Program of the National Science Foundation under award
DMR05-20415. Portions of this research were carried out at the Stanford
Synchrotron Radiation Laboratory, a national user facility operated by
Stanford University on behalf of the U.S. Department of Energy, Office
of Basic Energy Sciences.
NR 51
TC 90
Z9 93
U1 1
U2 54
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 APR 1
PY 2009
VL 43
IS 7
BP 2589
EP 2594
DI 10.1021/es802806n
PG 6
WC Engineering, Environmental; Environmental Sciences
SC Engineering; Environmental Sciences & Ecology
GA 427DI
UT WOS:000264759600072
PM 19452921
ER
PT J
AU Tseng, CC
Voytovych, DM
Kulatilaka, WD
Bhuiyan, AH
Lucht, RP
Merkle, CL
Hulka, JR
Jones, GW
AF Tseng, C. C.
Voytovych, D. M.
Kulatilaka, W. D.
Bhuiyan, A. H.
Lucht, R. P.
Merkle, C. L.
Hulka, J. R.
Jones, G. W.
TI Structure and mixing of a transient flow of helium injected into an
established flow of nitrogen: two dimensional measurement and simulation
SO EXPERIMENTS IN FLUIDS
LA English
DT Article
ID INDUCED FLUORESCENCE MEASUREMENTS; TURBULENT; LAYERS; INSTABILITIES;
TRANSITION; FRACTION; FLAMES; NO
AB The transient injection and mixing between nitrogen and helium in a confined chamber at atmospheric pressure is studied experimentally. The 2D injector and mixing chamber contained a middle injection slot for nitrogen flanked by a pair of outer slots for helium. Experiments were conducted by introducing the helium streams into a previously established quasi-steady flow of nitrogen. The nitrogen stream was seeded with nitric oxide (NO) that served as a source for quantitative, planar laser-induced fluorescence (PLIF) imaging of the transient mixing process. PLIF images were acquired by triggering an Nd:YAG laser system at selected times following helium valve actuation. The observed flow structures and extent of mixing between the two streams proved to be highly unsteady and irregular with the helium/nitrogen jets frequently deviating from the centerline toward the confining walls. Representative unsteady CFD solutions also show this same absence of symmetry and the same general flow structures as the measurements, however, they predict somewhat higher helium concentration in recirculation regions than were observed in the measurements.
C1 [Voytovych, D. M.; Merkle, C. L.] Purdue Univ, Sch Aeronaut & Astronaut, W Lafayette, IN 47907 USA.
[Tseng, C. C.; Voytovych, D. M.; Kulatilaka, W. D.; Bhuiyan, A. H.; Lucht, R. P.; Merkle, C. L.] Purdue Univ, Sch Mech Engn, W Lafayette, IN 47907 USA.
[Hulka, J. R.] Jacobs ESTS Grp, Huntsville, AL 35812 USA.
[Jones, G. W.] NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA.
RP Voytovych, DM (reprint author), Purdue Univ, Sch Aeronaut & Astronaut, W Lafayette, IN 47907 USA.
EM dvoyt@purdue.edu; lucht@purdue.edu; merkle@purdue.edu
FU NASA Constellation University Institutes Project (CUIP) [NCC8-200]; Ms.
Claudia Meyer and Dr. Jeff Rybak of Glenn Research Center; NASA
Combustion Devices Injector Technology (CDIT) Program; LabVIEW program
FX This project is supported by the NASA Constellation University
Institutes Project (CUIP) Program under Grant NCC8-200 with Ms. Claudia
Meyer and Dr. Jeff Rybak of Glenn Research Center as contract monitors.
The funding for the fabrication of the injector assembly and for the
initial measurements was provided by the NASA Combustion Devices
Injector Technology (CDIT) Program. The substantial efforts of Dr. James
Sisco and Dr. William Anderson (Purdue) in designing the injector, and
of Dr. Thomas Anderson (Purdue) in developing the LabVIEW program are
gratefully acknowledged.
NR 23
TC 4
Z9 4
U1 1
U2 4
PU SPRINGER
PI NEW YORK
PA 233 SPRING ST, NEW YORK, NY 10013 USA
SN 0723-4864
J9 EXP FLUIDS
JI Exp. Fluids
PD APR
PY 2009
VL 46
IS 4
BP 559
EP 575
DI 10.1007/s00348-008-0581-6
PG 17
WC Engineering, Mechanical; Mechanics
SC Engineering; Mechanics
GA 431RQ
UT WOS:000265081300001
ER
PT J
AU Evans, JM
Ayanampudi, V
Howarth, M
Moore, F
Patwardhan, A
Knapp, C
AF Evans, Joyce McClendon
Ayanampudi, Vijaya
Howarth, Mark
Moore, Fritz
Patwardhan, Abjihit
Knapp, Charles
TI Cardiovascular Regulation During Artificial Gravity Stress
SO FASEB JOURNAL
LA English
DT Meeting Abstract
C1 [Evans, Joyce McClendon; Ayanampudi, Vijaya; Howarth, Mark; Patwardhan, Abjihit; Knapp, Charles] Univ Kentucky, Lexington, KY USA.
[Moore, Fritz] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA.
NR 0
TC 0
Z9 0
U1 0
U2 0
PU FEDERATION AMER SOC EXP BIOL
PI BETHESDA
PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA
SN 0892-6638
J9 FASEB J
JI Faseb J.
PD APR
PY 2009
VL 23
MA 1035.3
PG 1
WC Biochemistry & Molecular Biology; Biology; Cell Biology
SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other
Topics; Cell Biology
GA V27OC
UT WOS:000208621505525
ER
PT J
AU Evans, JM
Meng, M
Patwardhan, A
Stenger, M
Feiveson, A
Knapp, C
AF Evans, Joyce McClendon
Meng, Martha
Patwardhan, Abjihit
Stenger, Michael
Feiveson, Alan
Knapp, Charles
TI Prediction of Changes in Orthostatic Tolerance after Head down Bed Rest
With and Without Artificial gravity Training
SO FASEB JOURNAL
LA English
DT Meeting Abstract
C1 [Evans, Joyce McClendon; Meng, Martha; Patwardhan, Abjihit; Knapp, Charles] Univ Kentucky, Ctr Biomed Engn, Lexington, KY 40506 USA.
[Stenger, Michael] Wyle Labs, Houston, TX USA.
[Feiveson, Alan] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA.
NR 0
TC 0
Z9 0
U1 0
U2 0
PU FEDERATION AMER SOC EXP BIOL
PI BETHESDA
PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA
SN 0892-6638
J9 FASEB J
JI Faseb J.
PD APR
PY 2009
VL 23
MA 1035.2
PG 1
WC Biochemistry & Molecular Biology; Biology; Cell Biology
SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other
Topics; Cell Biology
GA V27OC
UT WOS:000208621505262
ER
PT J
AU Dillon, JG
Miller, S
Bebout, B
Hullar, M
Pinel, N
Stahl, DA
AF Dillon, Jesse G.
Miller, Scott
Bebout, Brad
Hullar, Meredith
Pinel, Nicolas
Stahl, David A.
TI Spatial and temporal variability in a stratified hypersaline microbial
mat community
SO FEMS MICROBIOLOGY ECOLOGY
LA English
DT Article
DE microbial mat; hypersaline; T-RFLP; migration; cyanobacteria; Guerrero
Negro
ID SALINS-DE-GIRAUD; SULFATE-REDUCING BACTERIA; SOLAR LAKE SINAI;
CYANOBACTERIAL MATS; MEDITERRANEAN SALTERNS; VISIBLE IRRADIANCE;
VERTICAL MIGRATION; GUERRERO NEGRO; DIVERSITY; PHOTOSYNTHESIS
AB Hypersaline microbial mat communities have recently been shown to be more diverse than once thought. The variability in community composition of hypersaline mats, both in terms of spatial and temporal dimensions, is still poorly understood. Because this information is essential to understanding the complex biotic and abiotic interactions within these communities, terminal restriction fragment analysis and 16S rRNA gene sequencing were used to characterize the near-surface community of a hypersaline microbial mat in Guerrero Negro, Mexico. Core samples were analyzed to assay community variability over large regional scales (centimeter to kilometer) and to track depth-related changes in population distribution at 250-mu m intervals over a diel period. Significant changes in total species diversity were observed at increasing distances across the mat surface; however, key species (e.g. Microcoleus sp.) were identified throughout the mat. The vertical position and abundance of > 50% of the 60 peaks detected varied dramatically over a diel cycle, including Beggiatoa sp., cyanobacteria, Chloroflexus sp., Halochromatium sp., Bacteroidetes sp. and several as-yet-identified bacteria. Many of these migrations correlated strongly with diel changes in redox conditions within the mat, contributing to strong day-night community structure differences.
C1 [Dillon, Jesse G.; Pinel, Nicolas] Univ Washington, Dept Microbiol, Seattle, WA 98195 USA.
[Dillon, Jesse G.; Hullar, Meredith; Pinel, Nicolas; Stahl, David A.] Univ Washington, NASA Astrobiol Inst, Seattle, WA 98195 USA.
[Miller, Scott] Univ Montana, Div Biol Sci, Missoula, MT 59812 USA.
[Bebout, Brad] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA.
[Hullar, Meredith; Stahl, David A.] Univ Washington, Dept Civil & Environm Engn, Seattle, WA 98195 USA.
RP Dillon, JG (reprint author), Calif State Univ Long Beach, Dept Biol Sci, Long Beach, CA 90840 USA.
EM jdillon@csulb.edu
FU NSF-IGERT [DGE-9870713]; NSF [DEB-0213186]; NASA NAI [NCC2-1273]
FX This work was supported by NSF-IGERT grant (DGE-9870713) funding to
J.G.D. and NSF grant (DEB-0213186) and NASA NAI grant (NCC2-1273)
support to D.A.S. and J.G.D. We would like to thank Dr David Des Marais
and all of the NASA Ames EMERG group for logistical support and field
assistance on this project. We would like to thank the Mexican
government and the Exportadora de Sal, SA, for granting permission to
perform research in the salt ponds. We would like to thank Michael
Rothrock and Dr Ferran Garcia-Pichel for assistance with experimental
design and sampling. We would also like to thank Drs Jennifer Glick and
Joseph Beavo for the use of the cryotome. Dr Ann Bernhard is gratefully
acknowledged for her assistance in using PC-ORD.
NR 51
TC 27
Z9 27
U1 1
U2 26
PU WILEY-BLACKWELL PUBLISHING, INC
PI MALDEN
PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA
SN 0168-6496
J9 FEMS MICROBIOL ECOL
JI FEMS Microbiol. Ecol.
PD APR
PY 2009
VL 68
IS 1
BP 46
EP 58
DI 10.1111/j.1574-6941.2009.00647.x
PG 13
WC Microbiology
SC Microbiology
GA 415BN
UT WOS:000263909400005
PM 19175677
ER
PT J
AU Sewall, FF
Rodgveller, CJ
AF Sewall, Fletcher F.
Rodgveller, Cara J.
TI Changes in body composition and fatty acid profile during embryogenesis
of quillback rockfish (Sebastes maliger)
SO FISHERY BULLETIN
LA English
DT Article
ID EMBRYONIC-DEVELOPMENT; YELLOWTAIL ROCKFISH; MARINE FISH; LIPIDS;
METABOLISM; SCHLEGELI; DYNAMICS; MELANOPS
AB We investigated developmental changes in the body compositions and fatty acid (FA) profiles of embryos and preparturition larvae of the quillback rockfish (Sebastes maliger). Comparisons of proximate composition data from early-stage embryos with data from hatched preparturition larvae taken from wild-caught gravid females indicated that embryos gain over one-third their weight in moisture while consuming 20% of their dry tissue mass for energy as they develop into larvae. Lipid contributed 60% of the energy consumed and was depleted more rapidly than protein, indicating a protein-sparing effect. Oil globule volume was strongly correlated with lipid levels, affirming its utility as an indicator of energetic status. FA profiles of early embryos differed significantly from those of hatched larvae. Differences in the relative abundances of FAs between early embryos and hatched larvae indicated different FA depletion rates during embryonic development. We conclude that some metabolically important FAs may prove useful in assessing the condition of embryos and preparturition larvae, particularly 20:4n-6, which cannot be synthesized by many marine fish and which is conserved during embryogenesis. Variability in body composition and energy use among rockfish species should be considered when interpreting any measures of condition.
C1 [Sewall, Fletcher F.; Rodgveller, Cara J.] NOAA, Natl Marine Fisheries Serv, Alaska Fisheries Sci Ctr, Auke Bay Labs,Ted Stevens Marine Res Inst, Juneau, AK 99801 USA.
RP Sewall, FF (reprint author), NOAA, Natl Marine Fisheries Serv, Alaska Fisheries Sci Ctr, Auke Bay Labs,Ted Stevens Marine Res Inst, 17109 Pt Lena Loop Rd, Juneau, AK 99801 USA.
EM Fletcher.Sewall@noaa.gov
NR 30
TC 6
Z9 6
U1 0
U2 2
PU NATL MARINE FISHERIES SERVICE SCIENTIFIC PUBL OFFICE
PI SEATTLE
PA 7600 SAND POINT WAY NE BIN C15700, SEATTLE, WA 98115 USA
SN 0090-0656
J9 FISH B-NOAA
JI Fish. Bull.
PD APR
PY 2009
VL 107
IS 2
BP 207
EP 220
PG 14
WC Fisheries
SC Fisheries
GA 435VG
UT WOS:000265370800008
ER
PT J
AU Akkerman, V
Ivanov, M
Bychkov, V
AF Akkerman, V'yacheslav
Ivanov, Mikhail
Bychkov, Vitaly
TI Turbulent Flow Produced by Piston Motion in a Spark-ignition Engine
SO FLOW TURBULENCE AND COMBUSTION
LA English
DT Article
DE Spark-ignition (SI) engine; Piston motion; Direct numerical simulations
ID BURNING VELOCITY; PREMIXED FLAMES; LENGTH SCALES; PROPAGATION;
COMBUSTION; DISSIPATION; INSTABILITY; SIMULATION; EQUATION; MODEL
AB Turbulence produced by the piston motion in spark-ignition engines is studied by 2D axisymmetric numerical simulations in the cylindrical geometry as in the theoretical and experimental work by Breuer et al. (Flow Turbul Combust 74:145, 2005). The simulations are based on the Navier-Stokes gas-dynamic equations including viscosity, thermal conduction and non-slip at the walls. Piston motion is taken into account as a boundary condition. The turbulent flow is investigated for a wide range of the engine speed, 1,000-4,000 rpm, assuming both zero and non-zero initial turbulence. The turbulent rms-velocity and the integral length scale are investigated in axial and radial directions. The rms-turbulent velocity is typically an order-of-magnitude smaller than the piston speed. In the case of zero initial turbulence, the flow at the top-dead-center may be described as a combination of two large-scale vortex rings of a size determined by the engine geometry. When initial turbulence is strong, then the integral turbulent length demonstrates self-similar properties in a large range of crank angles. The results obtained agree with the experimental observations of Breuer et al. (Flow Turbul Combust 74:145, 2005).
C1 [Akkerman, V'yacheslav; Ivanov, Mikhail; Bychkov, Vitaly] Umea Univ, Dept Phys, S-90187 Umea, Sweden.
[Akkerman, V'yacheslav; Ivanov, Mikhail] Russian Acad Sci, Nucl Safety Inst, Moscow 115191, Russia.
[Akkerman, V'yacheslav; Ivanov, Mikhail] Moscow Inst Phys & Technol, Dept Phys & Power Engn, Dolgoprudnyi 141700, Moscow Region, Russia.
RP Akkerman, V (reprint author), Stanford Univ, NASA, Ames Res Ctr, 488 Escondido Mall, Stanford, CA 94305 USA.
EM akkerman@stanford.edu
RI Akkerman, V'yacheslav/H-7982-2012
FU Swedish Research Council (VR); Kempe Foundation
FX The authors are grateful to Martin Oberlack for the data of paper [1]
reproduced in Figs. 8, 9b, c. We also thank Mikhail Modestov for useful
discussions. This work has been supported by the Swedish Research
Council (VR) and by the Kempe Foundation.
NR 45
TC 3
Z9 4
U1 0
U2 8
PU SPRINGER
PI DORDRECHT
PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS
SN 1386-6184
EI 1573-1987
J9 FLOW TURBUL COMBUST
JI Flow Turbul. Combust.
PD APR
PY 2009
VL 82
IS 3
BP 317
EP 337
DI 10.1007/s10494-008-9179-6
PG 21
WC Thermodynamics; Mechanics
SC Thermodynamics; Mechanics
GA 423TZ
UT WOS:000264519900002
ER
PT J
AU Park, J
Garrison, DH
Bogard, DD
AF Park, Jisun
Garrison, Daniel H.
Bogard, Donald D.
TI Ar-39-Ar-40 ages of martian nakhlites
SO GEOCHIMICA ET COSMOCHIMICA ACTA
LA English
DT Article
ID BASALTIC SHERGOTTITES; NOBLE-GASES; PARENT BODY; METEORITES; MARS;
PETROLOGY; PETROGENESIS; AR-40-AR-39; ATMOSPHERE; MIL-03346
AB We report Ar-39-Ar-40 ages of whole rock (WR) and plagioclase and pyroxene mineral separates of nakhlites MIL 03346 and Y-000593, and of WR samples of nakhlites NWA 998 and Nakhla. All age spectra are complex and indicate variable degrees of Ar-39 recoil and variable amounts of trapped Ar-40 in the samples. Thus, we examine possible Ar-Ar ages in several ways. From consideration of both limited plateau ages and isochron ages, we prefer Ar-Ar ages of NWA 998 = 1334 +/- 11 Ma, MIL 03346 = 1368 +/- 83 Ma (mesostasis) and 1334 +/- 54 Ma (pyroxene), Y-000593 = 1367 +/- 7 Ma, and Nakhla = 1357 +/- 11 Ma, (2 sigma errors). For NWA 998 and MIL 03346 the Ar-Ar ages are within uncertainties of preliminary Rb-Sr isochron ages reported in the literature. These Ar-Ar ages for Y-000593 and Nakhla are several Ma older than Sm-Nd ages reported in the literature. We conclude that the major factor in producing Ar-Ar ages slightly too old is the presence of small amounts of trapped martian or terrestrial Ar-40 on weathered grain surfaces that was degassed along with the first several percent of Ar-39. A total K-Ar-40 isochron for WR and mineral data from five nakhlites analyzed by us, plus Lafayette data in the literature, gives an isochron age of 1325 +/- 18 Ma (2 sigma). We emphasize the precision of this isochron over the value of the isochron age. Our Ar-Ar data are consistent with a common formation age for nakhlites. The cosmic-ray exposure (CRE) age for NWA 998 of similar to 12 Ma is also similar to CRE ages for other nakhlites. (c) Published by Elsevier Ltd.
C1 [Park, Jisun; Garrison, Daniel H.; Bogard, Donald D.] NASA, Lyndon B Johnson Space Ctr, ARES, Code KR, Houston, TX 77058 USA.
[Garrison, Daniel H.] ESCD Barrios, JE23, Houston, TX 77058 USA.
RP Bogard, DD (reprint author), NASA, Lyndon B Johnson Space Ctr, ARES, Code KR, Houston, TX 77058 USA.
EM donald.d.bogard@nasa.gov
NR 54
TC 12
Z9 13
U1 1
U2 2
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 APR 1
PY 2009
VL 73
IS 7
BP 2177
EP 2189
DI 10.1016/j.gca.2008.12.027
PG 13
WC Geochemistry & Geophysics
SC Geochemistry & Geophysics
GA 423TL
UT WOS:000264518500024
ER
PT J
AU Ellis, JT
Morrison, RF
Priest, BH
AF Ellis, Jean T.
Morrison, Rebecca F.
Priest, Barry H.
TI Detecting impacts of sand grains with a microphone system in field
conditions
SO GEOMORPHOLOGY
LA English
DT Article; Proceedings Paper
CT 6th International Conference on Aeolian Research (ICAR VI)
CY JUL 24-28, 2006
CL Univ Guelph, Guelph, CANADA
HO Univ Guelph
DE Wind blown sediment; Miniphone; Saltation transport; Coastal
geomorphology; Aeolian geomorphology
ID AEOLIAN TRANSPORT; TRAP DESIGN; SALTATION; WIND; BEACH; LAYER
AB This paper describes the "miniplione," an instrument to measure aeolian saltation. This instrument is a modified electret microphone that detects the impacts of individual grains. The unidirectional miniphone is inexpensive (approximately US$10), small, and poses minimal disruption to the wind field. It can be sampled at rates up to 44,100 Hz using commonly available Sound card technology or it can be interfaced with a data acquisition system. Data from deployments on beaches on Marco Island, FL, USA and near Shoalhaven Heads, NSW, Australia using sample rates of 44,100 Hz and 6000 Hz, are presented. An algorithm for identifying discrete impacts of grains is described. The number of saltation impacts was not reduced when sub-sampling a record from 44,100 Hz to 6000 Hz. The most immediate use for the miniphone is for short-term deployments to detect unsteadiness in the saltation field. (C) 2008 Elsevier B.V. All rights reserved.
C1 [Ellis, Jean T.; Priest, Barry H.] Texas A&M Univ, Dept Geog, College Stn, TX 77843 USA.
[Morrison, Rebecca F.] Texas A&M Univ, Dept Elect Engn, College Stn, TX 77843 USA.
RP Ellis, JT (reprint author), NASA, Div Sci & Technol, Stennis Space Ctr, MS 39529 USA.
EM jean.t.ellis@nasa.gov
NR 34
TC 31
Z9 33
U1 1
U2 11
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0169-555X
EI 1872-695X
J9 GEOMORPHOLOGY
JI Geomorphology
PD APR 1
PY 2009
VL 105
IS 1-2
SI SI
BP 87
EP 94
DI 10.1016/j.geomorph.2008.02.017
PG 8
WC Geography, Physical; Geosciences, Multidisciplinary
SC Physical Geography; Geology
GA 414LZ
UT WOS:000263866600010
ER
PT J
AU Hu, SW
Kim, MHY
McClellan, GE
Cucinotta, FA
AF Hu, Shaowen
Kim, Myung-Hee Y.
McClellan, Gene E.
Cucinotta, Francis A.
TI MODELING THE ACUTE HEALTH EFFECTS OF ASTRONAUTS FROM EXPOSURE TO LARGE
SOLAR PARTICLE EVENTS
SO HEALTH PHYSICS
LA English
DT Article
DE analysis; risk; computer calculations; health effects; radiation risk
ID GALACTIC COSMIC-RAYS; SPACE RADIATION; LETHALITY; DOSIMETRY; HUMANS;
ISSUES; RISK; RBE; GY
AB Radiation exposure from Solar Particle Events (SPE) presents a significant health concern for astronauts for exploration missions outside the protection of the Earth's magnetic field, which could impair their performance and result in the possibility of failure of the mission. Assessing the potential for early radiation effects under such adverse conditions is of prime importance. Here we apply a biologically based mathematical model that describes the dose- and time-dependent early human responses that constitute the prodromal syndromes to consider acute risks from SPEs. We examine the possible early effects on crews from exposure to some historically large solar events on lunar and/or Mars missions. The doses and dose rates of specific organs were calculated using the Baryon radiation transport (BRYNTRN) code and a computerized anatomical man model, while the hazard of the early radiation effects and performance reduction were calculated using the Radiation-Induced Performance Decrement (RIPD) code. Based on model assumptions we show that exposure to these historical events would cause moderate early health effects to crew members inside a typical spacecraft or during extra-vehicular activities, if effective shielding and medical countermeasure tactics were not provided. We also calculate possible even worse cases (double intensity, multiple occurrences in a short period of time, etc.) to estimate the severity, onset and duration of various types of early illness. Uncertainties in the calculation due to limited data on relative biological effectiveness and dose-rate modifying factors for protons and secondary radiation, and the identification of sensitive sites in critical organs are discussed. Health Phys. 96(4):465-476; 2009
C1 [Cucinotta, Francis A.] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA.
[Hu, Shaowen; Kim, Myung-Hee Y.] Univ Space Res Assoc, Div Space Life Sci, Houston, TX 77058 USA.
[McClellan, Gene E.] Appl Res Associates Inc, Arlington, VA 22203 USA.
RP Cucinotta, FA (reprint author), NASA, Lyndon B Johnson Space Ctr, 2101 NASA Pkwy, Houston, TX 77058 USA.
EM Shaowen.Hu-1@nasa.gov; Francis.A.Cuciniotta@NASA.gov
FU Defense Threat Reduction Agency [DTRA01-03-D-0014-0015]
FX We wish to extend a note of gratitude to John Moulder for discussions on
models of acute risks. Funding for this study was provided by the NASA
Space Radiation Program, Risk Assessment Project. One of the authors
(GEM) participated with support from the Defense Threat Reduction
Agency, Contract DTRA01-03-D-0014-0015.
NR 38
TC 37
Z9 38
U1 6
U2 12
PU LIPPINCOTT WILLIAMS & WILKINS
PI PHILADELPHIA
PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA
SN 0017-9078
EI 1538-5159
J9 HEALTH PHYS
JI Health Phys.
PD APR
PY 2009
VL 96
IS 4
BP 465
EP 476
PG 12
WC Environmental Sciences; Public, Environmental & Occupational Health;
Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical
Imaging
SC Environmental Sciences & Ecology; Public, Environmental & Occupational
Health; Nuclear Science & Technology; Radiology, Nuclear Medicine &
Medical Imaging
GA 420BX
UT WOS:000264264500006
PM 19276707
ER
PT J
AU Thompson, WT
AF Thompson, W. T.
TI 3D triangulation of a Sun-grazing comet
SO ICARUS
LA English
DT Article
DE Comets, dynamics; Data reduction techniques
ID SUNGRAZING COMETS; STEREO; SOLAR; MISSION; SECCHI
AB The bright Kreutz Comet C/2007 L3 (SOHO) entered the fields of view of the twin Solar Terrestrial Relations Observatory (STEREO) COR1 telescopes oil 7-8 June 2007. The 12 degrees separation between the two spacecraft at the time afforded the opportunity to derive the position of the comet's tail in three-dimensional space using direct triangulation. The track of the comet's orbit is compared against more traditional orbital calculations using observations from the STEREO COR2 telescopes, and from the Large Angle and Spectrometric Coronagraph (LASCO) aboard the Solar and Heliospheric Observatory (SOHO). The shape of the comet's tail shows that it is composed of dust particles released when the comet was between 18 and 22 solar radii, with no significant dust production after that. The comet did not survive perihelion passage, but a rare faint remnant of the comet tail persisted for several hours after the break-up, and was seen by both the SOHO and STEREO coronagraphs to drift slowly away from the Sun. This tail remnant was found to be composed of particles far back from the head of the comet, The motion of the tail remnant shows a loss of angular momentum during the passage through the solar corona. Atmospheric drag is estimated to account for a significant fraction of this change in angular momentum. but indications are that other mechanisms may be required to completely account for the total amount of change. (C) 2008 Elsevier Inc. All rights reserved.
C1 NASA, Goddard Space Flight Ctr, Adnet Syst Inc, Greenbelt, MD 20771 USA.
RP Thompson, WT (reprint author), NASA, Goddard Space Flight Ctr, Adnet Syst Inc, Code 671, Greenbelt, MD 20771 USA.
EM William.T.Thompson@nasa.gov
RI Thompson, William/D-7376-2012
FU NASA [NNG06EB68C]
FX The author would like to thank Karl Battams for his many helpful
comments, and to the anonymous reviewer who suggested the approach
resulting in Eq. (4). This work was Supported by NASA grant NNG06EB68C.
NR 16
TC 23
Z9 23
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 APR
PY 2009
VL 200
IS 2
BP 351
EP 357
DI 10.1016/j.icarus.2008.12.011
PG 7
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 424NH
UT WOS:000264572900001
ER
PT J
AU Williams, KE
Toon, OB
Heldmann, JL
Mellon, MT
AF Williams, K. E.
Toon, O. B.
Heldmann, J. L.
Mellon, M. T.
TI Ancient melting of mid-latitude snowpacks on Mars as a water source for
gullies
SO ICARUS
LA English
DT Article
DE Ices; Mars, surface
ID POTENTIAL FORMATION MECHANISMS; MARTIAN GULLIES; VALLEY FORMATION;
SUMMIT SNOWPACK; CARBON-DIOXIDE; SURFACE RUNOFF; DEPOSITS; FEATURES;
ORIGIN; CONSTRAINTS
AB We hypothesize that during past epochs of high obliquity seasonal snowfields at mid-latitudes melted to produce springtime sediment-rich surface flows resulting in gully formation. Significant seasonal mid-latitude snowfall does not occur on Mars today. General Circulation Model (GCM) results, however, suggest that under past climate conditions there may have been centimeters of seasonal mid-latitude snowfall [Mischna, M.A., Richardson, M.I., Wilson, R.J., McCleese, D.J., 2003. J. Geophys. Res. Planets 108, doi:10.1029/2003JE002051. 5062). Gully locations have been tabulated by several researchers (e.g. [Heldmann, J.L., Mellon, M.T., 2004. Icarus 168, 285-304; Heldmann, J.L., Carlsson, E., johansson, H., Mellon, M.T., Toon, O.B., 2007. Icarus 188, 324-344; Malin, M.C., Edgett, K.S., 2000. Science 288, 233023351) and found to cot-respond to mid-latitude bands. A natural question is whether the latitudinal bands where the gullies are located correspond to areas where the ancient snowfalls may have melted, producing runoff which may have incised gullies. In this study we model thin snowpacks with thicknesses similar to those predicted by [Mischna, M.A., Richardson, M.I., Wilson, R.J., McCleese, D.J., 2003. J. Geophys. Res. Planets 108, doi:10.1029/2003JE002051. 50621. We model these snowpacks under past climate regimes in order to determine whether snowmelt runoff could have occurred, and whether significant amounts of warm soil (T > 273 K) existed on both poleward and equatorward slopes in the regions where gullies exist. Both warm soil and water amounts are modeled because soil and water may have mixed to form a sediment-rich flow. We begin by applying the snowpack model of Williams et al. [Williams, K.E., Toon, O.B., Heldmann, J.E., Mellon, M., 2008. Icarus 196, 565-5771 to past climate regimes characterized by obliquities of 35 degrees (600 ka before present) and 45 degrees (5.5 ma before present), and to all latitudes between 70 degrees N and 70 degrees S. We find that the regions containing significant snowmelt runoff correspond to the regions identified by Heldmann and Mellon [Heldmann, j.L., Mellon, M.T., 2004. Icarus 168, 285-304], Heldmann et al. [Heldmann, J.L, Carlsson, E., johansson, H., Mellon, M.T., Toon, O.B., 2007. Icarus 188, 324-344] and Malin and Edgett [Malin, M.C., Edgett, K.S., 2000. Science 288, 2330-2335] as containing large numbers of gullies. We find that the snowmelt runoff (>1 mm, with equivalent rainfall rates of 0.25 mm/h) and warm soil (>1 cm depth) would have occurred on slopes within the gullied latitudinal bands. The snowfall amounts modeled are predicted to be seasonal [Mischna, M.A., Richardson, M.I., Wilson, Rj., McCleese, D.J., 2003. J. Geophys. Res. Planets 108, doi: 10.1029/2003JE002051. 5062 1, and our modeling finds that under the previous climate regimes there would have been meltwater present on the slopes in question for brief periods of time, on the order of days, each year. Our model provides a simple explanation for the latitudinal distribution of the gullies, and also suggests that the gullies date to times when water migrated away from the present poles to the mid-latitudes. (C) 2008 Elsevier Inc. All rights reserved.
C1 [Williams, K. E.; Toon, O. B.; Mellon, M. T.] Univ Colorado, Dept Atmospher & Ocean Sci, Boulder, CO 80309 USA.
[Heldmann, J. L.] NASA, Ames Res Ctr, Div Space Sci & Astrobiol, Moffett Field, CA 94035 USA.
[Williams, K. E.; Mellon, M. T.] Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80309 USA.
RP Williams, KE (reprint author), NASA Ames, Mail Stop 245, Moffett Field, CA 94035 USA.
EM kaj.e.williams@nasa.gov
RI Mellon, Michael/C-3456-2016
NR 32
TC 54
Z9 54
U1 2
U2 6
PU ACADEMIC PRESS INC ELSEVIER SCIENCE
PI SAN DIEGO
PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA
SN 0019-1035
J9 ICARUS
JI Icarus
PD APR
PY 2009
VL 200
IS 2
BP 418
EP 425
DI 10.1016/j.icarus.2008.12.013
PG 8
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 424NH
UT WOS:000264572900007
ER
PT J
AU Janchen, J
Morris, RV
Bish, DL
Janssen, M
Hellwig, U
AF Jaenchen, Jochen
Morris, Richard V.
Bish, David L.
Janssen, Mareike
Hellwig, Udo
TI The H2O and CO2 adsorption properties of phyllosilicate-poor palagonitic
dust and smectites under martian environmental conditions
SO ICARUS
LA English
DT Article
DE Mars, surface; Mineralogy
ID MARS; INSTRUMENT; REGOLITH; MINERALS; ANALOG
AB The recent detection of up to similar to 10 wt% water-equivalent H heterogeneously distributed in the upper meter of the equatorial regions of the martian surface and the presence of the 3-mu m hydrations feature across the entire planet raises the question whether martian surficial dust can account for this water-equivalent H. We have investigated the H2O and CO2 adsorption properties of palagonitic dust (<5 mu m size fraction of phyllosilicate-poor palagonitic tephra HWMK919) as a martian dust analog and two smectites under simulated martian equatorial surface conditions. Our results show that the palagonitic dust, which contains hydrated and hydroxylated volcanic glass of basaltic composition, accommodates significantly more H2O under comparable humidity and temperature conditions than do the smectites nontronite and montmorillonite. (C) 2008 Elsevier Inc. All rights reserved.
C1 [Jaenchen, Jochen] ZeoSolar eV, TFH Wildau, D-12489 Berlin, Germany.
[Jaenchen, Jochen; Janssen, Mareike; Hellwig, Udo] Univ Appl Sci, TFH Wildau, D-15745 Wildau, Germany.
[Morris, Richard V.] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA.
[Bish, David L.] Indiana Univ, Bloomington, IN 47405 USA.
RP Janchen, J (reprint author), ZeoSolar eV, TFH Wildau, Volmerstr 13, D-12489 Berlin, Germany.
EM j.e.jaenchen@t-online.de
FU International Space Science Institute Bern, Switzerland; NASA Mars
Fundamental Research Program; NASA Mars Exploration Rover Project; NASA
Mars Reconnaissance Orbiter CRISM Program; NASA CRISM-OMEGA
Collaboration; NASA Johnson Space Center
FX Support by the International Space Science Institute Bern, Switzerland,
is acknowledged. D.L.B. gratefully acknowledges support by the NASA Mars
Fundamental Research Program. R.V.M. acknowledges support of the NASA
Mars Exploration Rover Project, the NASA Mars Reconnaissance Orbiter
CRISM Program, the NASA CRISM-OMEGA Collaboration, and the NASA Johnson
Space Center.
NR 21
TC 21
Z9 21
U1 0
U2 7
PU ACADEMIC PRESS INC ELSEVIER SCIENCE
PI SAN DIEGO
PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA
SN 0019-1035
J9 ICARUS
JI Icarus
PD APR
PY 2009
VL 200
IS 2
BP 463
EP 467
DI 10.1016/j.icarus.2008.12.006
PG 5
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 424NH
UT WOS:000264572900011
ER
PT J
AU Cui, J
Yelle, RV
Vuitton, V
Waite, JH
Kasprzak, WT
Gell, DA
Niemann, HB
Muller-Wodarg, ICF
Borggren, N
Fletcher, GG
Patrick, EL
Raaen, E
Magee, BA
AF Cui, J.
Yelle, R. V.
Vuitton, V.
Waite, J. H., Jr.
Kasprzak, W. T.
Gell, D. A.
Niemann, H. B.
Mueller-Wodarg, I. C. F.
Borggren, N.
Fletcher, G. G.
Patrick, E. L.
Raaen, E.
Magee, B. A.
TI Analysis of Titan's neutral upper atmosphere from Cassini Ion Neutral
Mass Spectrometer measurements
SO ICARUS
LA English
DT Article
DE Atmospheres, composition; Atmospheres, structure; Titan
ID COUPLING PHOTOCHEMISTRY; VOYAGER-1 ENCOUNTER; HAZE FORMATION;
IONOSPHERE; NITROGEN; MODEL; THERMOSPHERE; CHEMISTRY; HC3N; HCN
AB In this paper we present all in-depth study of the distributions of various neutral species in Titan's upper atmosphere, between 950 and 1500 km for abundant species (N-2, CH4, H-2) and between 950 and 1200 km for other minor species. Our analysis is based on a large sample of Cassini/INMS (Ion Neutral Mass Spectrometer) measurements in the CSN (Closed Source Neutral) mode, obtained during 15 close flybys of Titan. To untangle the overlapping cracking patterns, we adopt singular Value Decomposition (SVD) to determine simultaneously the densities of different species. Except for N-2, CH4, H-2 and Ar-40 (as well as their isotopes), all species present density enhancements measured during the outbound legs. This can be interpreted as a result of wall effects, which Could be either adsorption/desorption of these molecules or heterogeneous surface chemistry of the associated radicals on the chamber walls. In this paper, we provide both direct inbound measurements assuming ram pressure enhancement only and abundances corrected for wall adsorption/desorption based on a simple model to reproduce the observed time behavior.
Among all minor species of photochemical interest, we have firm detections of C2H2, C2H4. C2H6, CH3C2H, C4H2, C6H6, CH3CN, HC3N, C2N2 and NH3 in Titan's upper atmosphere. Upper limits are given for other minor species. The globally averaged distributions of N-2, CH4 and H-2 are each modeled with the diffusion approximation. The N-2 profile Suggests all average thermospheric temperature of 151 K. The CH4 and H-2 profiles constrain their fluxes to be 2.6 x 10(9) cm(2) s (1) and 1.1 x 10(10) cm (2) S (1), referred to Titan's surface. Both fluxes are significantly higher than the jeans escape values. The INMs data also suggest horizontal/diurnal variations of temperature and neutral gas distribution in Titan's thermosphere. The equatorial region, the ramside, as well as the nightside hemisphere of Titan appear to be warmer and present some evidence for the depletion of light species such as CH4. Meridional variations of some heavy species are also Observed, with a trend of depletion toward the north pole. Though some of the above variations might be interpreted by either the solar-driven models or auroral-driven models, a physical scenario that reconciles all the observed horizontal/diurnal variations in a consistent way is still missing. With a careful evaluation of the effect of restricted sampling, some of the features shown in the INMS data are more likely to be observational biases. (C) 2008 Elsevier Inc. All rights reserved.
C1 [Cui, J.; Mueller-Wodarg, I. C. F.] Univ London Imperial Coll Sci Technol & Med, Space & Atmospher Phys Grp, London SW7 2BW, England.
[Cui, J.; Yelle, R. V.; Borggren, N.] Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA.
[Vuitton, V.] Univ Grenoble 1, CNRS, Lab Planetol Grenoble, Grenoble 9, France.
[Waite, J. H., Jr.; Gell, D. A.; Fletcher, G. G.; Magee, B. A.] SW Res Inst, San Antonio, TX 78228 USA.
[Kasprzak, W. T.; Niemann, H. B.; Patrick, E. L.; Raaen, E.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
RP Cui, J (reprint author), Univ London Imperial Coll Sci Technol & Med, Space & Atmospher Phys Grp, London SW7 2BW, England.
EM jcui@imperial.ac.uk
RI Mueller-Wodarg, Ingo/M-9945-2014
OI Mueller-Wodarg, Ingo/0000-0001-6308-7826
NR 66
TC 120
Z9 120
U1 2
U2 31
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 APR
PY 2009
VL 200
IS 2
BP 581
EP 615
DI 10.1016/j.icarus.2008.12.005
PG 35
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 424NH
UT WOS:000264572900021
ER
PT J
AU Dodson-Robinson, SE
Willacy, K
Bodenheimer, P
Turner, NJ
Beichman, CA
AF Dodson-Robinson, Sarah E.
Willacy, Karen
Bodenheimer, Peter
Turner, Neal J.
Beichman, Charles A.
TI Ice lines, planetesimal composition and solid surface density in the
solar nebula
SO ICARUS
LA English
DT Article
DE Solar nebula; Planetary formation; Ices
ID TURBULENT PROTOPLANETARY DISKS; SPECTRAL ENERGY-DISTRIBUTIONS;
MOLECULAR-HYDROGEN FORMATION; INTER-STELLAR CLOUDS; GAS-GRAIN CHEMISTRY;
ACCRETION DISKS; GIANT PLANETS; INTERSTELLAR CLOUDS; T-TAURI;
PROTOSTELLAR DISKS
AB To date, there is no core accretion simulation that can Successfully account for the formation of Uranus or Neptune within the observed 2-3 Myr lifetimes of protoplanetary disks. Since solid accretion rate is directly proportional to the available planetesimal surface density, one way to speed up planet formation is to take a full accounting of all the planetesimal-forming solids present in the solar nebula. By combining a viscously evolving protostellar disk with a kinetic model of ice formation, which includes not just water but methane, ammonia, CO and 54 minor ices, we calculate the solid surface density of a possible giant planet-forming solar nebula as a function of heliocentric distance and time. Our results can be used to provide the starting planetesimal surface density and evolving solar nebula conditions for core accretion simulations, or to predict the composition of planetesimals as a function of radius. We find three effects that favor giant planet formation by the core accretion mechanism: (1) a decretion flow that brings mass from the inner solar nebula to the giant planet-forming region, (2) the fact that the ammonia and water ice lines should coincide, according to recent lab results from Collings et A [Collings, M.P., Anderson, M.A., Chen, R., Dever, J.W., Viti, S., Williams, D.A., McCoustra, M.R.S., 2004. Mon. Not. R. Astron. Soc. 354, 1133-1140], and (3) the presence of a substantial amount of methane ice in the trans-saturnian region. Our results show higher solid Surface densities than assumed in the core accretion models of Pollack et al. [Pollack, J.B., Hubickyj, O., Bodenheimer, P., Lissauer, J.J., Podolak, M., Greenzweig, Y., 1996. Icarus 124, 62-85] by a factor of 3-4 throughout the trans-saturnian region. We also discuss the location of ice lines and their movement through the solar nebula, and provide new constraints on the possible initial disk configurations from gravitational stability arguments. (c) 2008 Elsevier Inc. All rights reserved.
C1 [Dodson-Robinson, Sarah E.; Beichman, Charles A.] CALTECH, NASA, Exoplaret Sci Inst, Pasadena, CA 91125 USA.
[Willacy, Karen; Turner, Neal J.; Beichman, Charles A.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
[Bodenheimer, Peter] Univ Calif Santa Cruz, Dept Astron & Astrophys, Santa Cruz, CA 95064 USA.
RP Dodson-Robinson, SE (reprint author), CALTECH, NASA, Exoplaret Sci Inst, MC 100-22, Pasadena, CA 91125 USA.
EM sdr@ipac.caltech.edu
OI Turner, Neal/0000-0001-8292-1943
FU NSF Graduate Research Fellowship [AST-0507424]; College Scientists
Foundation; JPL Research and Technology Development Program; NASA
[NNX08AH82G]; Jet Propulsion Laboratory, California Institute of
Technology; National Aeronautics and Space Administration
FX We thank Julie Moses, Mark Marley and Doug Lin for helpful discussions
about the project design. S.D.R. was supported by grants from the NSF
Graduate Research Fellowship program and the Achievement Rewards for
College Scientists Foundation. K.W. and N.T. were supported by the JPL
Research and Technology Development Program. P.B. received funding from
NSF Grant AST-0507424 and NASA Origins Grant NNX08AH82G. The work of
K.W. and N.T. was carried out at the Jet Propulsion Laboratory,
California Institute of Technology under a contract with the National
Aeronautics and Space Administration, with funding provided by the JPL
Research and Technology Development Program.
NR 94
TC 54
Z9 54
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
J9 ICARUS
JI Icarus
PD APR
PY 2009
VL 200
IS 2
BP 672
EP 693
DI 10.1016/j.icarus.2008.11.023
PG 22
WC Astronomy & Astrophysics
SC Astronomy & Astrophysics
GA 424NH
UT WOS:000264572900026
ER
PT J
AU Webster, J
AF Webster, Jeffery
TI The Auditors Are Coming: A Practical Guide for Engineering Projects
SO IEEE AEROSPACE AND ELECTRONIC SYSTEMS MAGAZINE
LA English
DT Article
AB When management informs you that internal or external auditors are on their way to conduct an audit of your project, you may have many questions and, at times, few answers: Why are the auditors coming? Why now? What are they looking for? How long will the audit take? What can we do to prepare? What help will the project receive in responding to the auditors? This presents a description of the typical audit process, a list of do's and don'ts for projects undergoing an audit, how to design basic audit preparations into the project's design, and resources for, further information on auditing issues.
C1 CALTECH, Jet Prop Lab, Pasadena, CA USA.
RP Webster, J (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA USA.
FU National Aeronautics and Space Administration
FX The work described herein was performed at the Jet Propulsion
Laboratory, California Institute of Technology, under a contract with
the National Aeronautics and Space Administration.
NR 3
TC 0
Z9 0
U1 0
U2 1
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 APR
PY 2009
VL 24
IS 4
BP 9
EP 16
PG 8
WC Engineering, Aerospace; Engineering, Electrical & Electronic
SC Engineering
GA 435WO
UT WOS:000265374200003
ER
PT J
AU Jansma, PA
AF Jansma, P. A. Trisha
TI Got Software? What Managers and Engineers Need To Know
SO IEEE AEROSPACE AND ELECTRONIC SYSTEMS MAGAZINE
LA English
DT Article
AB As part of a JPL-wide software quality initiative aimed at addressing the challenges of developing, managing, and acquiring software, a team fit JPL generated a detailed Software Training Plan for both managers and engineers. The team took the approach of treating the software training program as though it were a system development task and went through all the typical phases of system development including requirements, design, and implementation.
During the requirements collection phase, the team conducted dozens; of interviews and identified the specific skills needed. The skills fell into categories such as software management, software engineering, systems engineering, and other technical areas. However, an equally important finding was that several "soft" skills were deemed critical for the successful and timely management and implementation of software-intensive systems. This discusses JPL's approach and "lessons learned" from planning and delivering a software training program. in an engineering and scientific environment.
C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
RP CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA.
FU National Aeronautics and Space Administration (NASA)
FX The work described herein was performed at the Jet Propulsion
Laboratory, California Institute of Technology under a contract with the
National Aeronautics and Space Administration (NASA). Reference herein
to any specific commercial product, process, or service by trade name,
trademark, manufacturer, or otherwise, does not constitute or imply its
endorsement by the United States Government, NASA, or the Jet Propulsion
Laboratory, California Institute of Technology.
NR 10
TC 0
Z9 0
U1 0
U2 1
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 APR
PY 2009
VL 24
IS 4
BP 25
EP 35
PG 11
WC Engineering, Aerospace; Engineering, Electrical & Electronic
SC Engineering
GA 435WO
UT WOS:000265374200005
ER
PT J
AU Acker, J
Lyon, P
Hoge, F
Shen, S
Roffer, M
Gawlikowski, G
AF Acker, James
Lyon, Paul
Hoge, Frank
Shen, Suhung
Roffer, Mitchell
Gawlikowski, Greg
TI Interaction of Hurricane Katrina With Optically Complex Water in the
Gulf of Mexico: Interpretation Using Satellite-Derived Inherent Optical
Properties and Chlorophyll Concentration
SO IEEE GEOSCIENCE AND REMOTE SENSING LETTERS
LA English
DT Article
DE Chlorophyll; dissolved organic matter; marine vegetation; optics;
plankton; remote sensing; sea coast; sea surface
ID UPPER OCEAN RESPONSE; DISSOLVED ORGANIC-MATTER; SOUTHERN STRAITS;
MATRIX-INVERSION; RADIANCE MODEL; RETRIEVAL; RESUSPENSION; VARIABILITY;
ABSORPTION; FLORIDA
AB When Hurricane Katrina passed over southern Florida, Florida Bay and the West Florida Shelf, and into the Gulf of Mexico, empirically derived chl a increases were observed in the Tortugas Gyre circulation feature, and in adjacent waters. Analysis of the empirically derived chl a increase within the gyre has been primarily attributed to initiation of a phytoplankton bloom promoted by nutrients upwelled by Katrina's winds. Detailed analysis of inherent optical properties derived from remotely sensed radiances, however, indicated the interaction of Katrina with shallow coastal and shelf waters likely entrained waters with higher concentrations of chromophoric dissolved organic matter (CDOM) into the gyre circulation, augmenting the chl a signa. Storm-induced upwelling would also transport optically active CDOM to the surface. Increases in empirically derived chl a in the Florida coastal waters influenced by Katrina's winds were therefore partly due to increased absorption by CDOM. This analysis indicates that elevated empirically derived chl a in hurricane-influenced waters should not be unambiguously attributed to increased phytoplankton productivity, particularly in an optically complex coastal environment.
C1 [Acker, James] NASA, Goddard Space Flight Ctr, Goddard Earth Sci Data & Informat Serv Ctr Wyle I, Greenbelt, MD 20771 USA.
[Lyon, Paul] USN, Res Lab, Ocean Opt Sect 7333, Stennis Space Ctr, Stennis Space Ctr, MS 39529 USA.
[Hoge, Frank] NASA, Goddard Space Flight Ctr, Wallops Flight Facil, Ocean Sci Branch,Hydrospher & Biospher Sci Lab, Wallops Isl, VA 23337 USA.
[Shen, Suhung] George Mason Univ, Goddard Earth Sci Data & Informat Serv Ctr, NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
[Roffer, Mitchell; Gawlikowski, Greg] Roffers Ocean Fishing Forecasting Serv Inc, Miami, FL 33155 USA.
RP Acker, J (reprint author), NASA, Goddard Space Flight Ctr, Goddard Earth Sci Data & Informat Serv Ctr Wyle I, Greenbelt, MD 20771 USA.
EM jim.acker@nasa.gov
NR 32
TC 9
Z9 9
U1 1
U2 25
PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
PI PISCATAWAY
PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA
SN 1545-598X
EI 1558-0571
J9 IEEE GEOSCI REMOTE S
JI IEEE Geosci. Remote Sens. Lett.
PD APR
PY 2009
VL 6
IS 2
BP 209
EP 213
DI 10.1109/LGRS.2008.2007658
PG 5
WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote
Sensing; Imaging Science & Photographic Technology
SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science
& Photographic Technology
GA 435XG
UT WOS:000265376000007
ER
PT J
AU Dinnat, EP
Abraham, S
Le Vine, DM
de Matthaeis, P
Jacob, D
AF Dinnat, Emmanuel Philippe
Abraham, Saji
Le Vine, David M.
de Matthaeis, Paolo
Jacob, Daniel
TI Effect of Emission From the Moon on Remote Sensing of Sea Surface
Salinity: An Example With the Aquarius Radiometer
SO IEEE GEOSCIENCE AND REMOTE SENSING LETTERS
LA English
DT Article
DE Microwave remote sensing; ocean salinity; radiation from Moon
ID L-BAND; SPACE; RADIATION; MISSION; WAVES; RADAR
AB This letter describes the effect of thermal emission from the Moon on remote sensing of sea surface salinity from space. In most cases, radiation from the Moon is negligible; however, at several times during the lunar cycle, it is possible for radiation to be reflected from the Earth's surface into the main beam of the radiometer antennas. The signal in such cases can be important because of the high radiometric accuracy required to monitor salinity. Examples are presented using the Aquarius orbit and antennas for both smooth and rough ocean surfaces.
C1 [Dinnat, Emmanuel Philippe; de Matthaeis, Paolo; Jacob, Daniel] Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA.
[Abraham, Saji; Le Vine, David M.] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
RP Dinnat, EP (reprint author), Univ Maryland Baltimore Cty, Goddard Earth Sci & Technol Ctr, Baltimore, MD 21228 USA.
EM David.M.Levine@nasa.gov
RI Dinnat, Emmanuel/D-7064-2012
OI Dinnat, Emmanuel/0000-0001-9003-1182
NR 21
TC 3
Z9 3
U1 0
U2 4
PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
PI PISCATAWAY
PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA
SN 1545-598X
J9 IEEE GEOSCI REMOTE S
JI IEEE Geosci. Remote Sens. Lett.
PD APR
PY 2009
VL 6
IS 2
BP 239
EP 243
DI 10.1109/LGRS.2008.2008822
PG 5
WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote
Sensing; Imaging Science & Photographic Technology
SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science
& Photographic Technology
GA 435XG
UT WOS:000265376000013
ER
PT J
AU Karam, LJ
Ebrahimi, T
Hemami, SS
Pappas, TN
Safranek, RJ
Wang, Z
Watson, AB
AF Karam, Lina J.
Ebrahimi, Touradj
Hemami, Sheila S.
Pappas, Thrasyvoulos N.
Safranek, Robert J.
Wang, Zhou
Watson, Andrew B.
TI Introduction to the Issue on Visual Media Quality Assessment
SO IEEE JOURNAL OF SELECTED TOPICS IN SIGNAL PROCESSING
LA English
DT Editorial Material
C1 [Karam, Lina J.] Arizona State Univ, Tempe, AZ 85287 USA.
[Ebrahimi, Touradj] LTSI, ITS, STI, EPFL, CH-1015 Lausanne, Switzerland.
[Ebrahimi, Touradj] Q2S NTNU, N-7034 Trondheim, Norway.
[Hemami, Sheila S.] Cornell Univ, Ithaca, NY 14853 USA.
[Pappas, Thrasyvoulos N.] Northwestern Univ, Evanston, IL 60208 USA.
[Safranek, Robert J.] Benevue Inc, Warren, NJ 07059 USA.
[Wang, Zhou] Univ Waterloo, Waterloo, ON N2L 3G1, Canada.
[Watson, Andrew B.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA.
RP Karam, LJ (reprint author), Arizona State Univ, Tempe, AZ 85287 USA.
RI Pappas, Thrasyvoulos/B-7261-2009; Pappas, Thrasyvoulos/D-5054-2013
NR 0
TC 22
Z9 22
U1 0
U2 7
PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
PI PISCATAWAY
PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA
SN 1932-4553
J9 IEEE J-STSP
JI IEEE J. Sel. Top. Signal Process.
PD APR
PY 2009
VL 3
IS 2
BP 189
EP 192
DI 10.1109/JSTSP.2009.2015485
PG 4
WC Engineering, Electrical & Electronic
SC Engineering
GA 439TH
UT WOS:000265649400001
ER
PT J
AU Siegel, PH
AF Siegel, Peter H.
TI Sir Jagadis Chunder Bose: Traversing the Interdisciplinary Gap Between
Physics and Biology
SO IEEE MICROWAVE MAGAZINE
LA English
DT Biographical-Item
C1 CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA.
RP Siegel, PH (reprint author), CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA.
NR 1
TC 1
Z9 1
U1 1
U2 1
PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
PI PISCATAWAY
PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA
SN 1527-3342
J9 IEEE MICROW MAG
JI IEEE Microw. Mag.
PD APR
PY 2009
VL 10
IS 2
BP 119
EP 121
DI 10.1109/MMM.2009.932241
PG 3
WC Engineering, Electrical & Electronic; Telecommunications
SC Engineering; Telecommunications
GA 420MJ
UT WOS:000264293600015
ER
PT J
AU Kennedy, TF
Fink, PW
Chu, AW
Champagne, NJ
Lin, GY
Khayat, MA
AF Kennedy, Timothy F.
Fink, Patrick W.
Chu, Andrew W.
Champagne, Nathan J., II
Lin, Gregory Y.
Khayat, Michael A.
TI Body-Worn E-Textile Antennas: The Good, the Low-Mass, and the Conformal
SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
LA English
DT Article
DE Antenna arrays; beamforming; conformal antennas; diversity methods;
e-textile antennas
ID 2.45 GHZ
AB Support of ever increasing applications for wireless data and communications on a body-centric platform requires novel antenna systems that can be integrated with the body-worn environment, while maintaining free-range of movement and minimal mass impact. E-textile antennas show great promise due to their ease of integration with other textile materials, and they are inherently low-mass and flexible relative to conventional antenna materials. Much attention has been given recently to multiple-antenna communication systems due to the increased performance compared to conventional single-antenna systems. For body-centric applications, the low-mass, flexibility, and integration simplicity of e-textile antennas can enable multiple-antenna systems, which otherwise would be precluded by the rigidity and mass of conventional antenna materials. Several examples of this are considered here with e-textile antennas in an array environment. A conventional microstrip array constructed with e-textiles is shown to have robust performance with moderate amounts of bending, similar to that which might be seen with body-worn arrays. In addition to the conventional array, a wide-band multiple-antenna system to support a variety of wireless communication protocols, while maintaining polarization diversity and excellent coverage over a majority of the radian sphere is demonstrated.
C1 [Kennedy, Timothy F.; Fink, Patrick W.; Chu, Andrew W.; Champagne, Nathan J., II; Lin, Gregory Y.; Khayat, Michael A.] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA.
RP Kennedy, TF (reprint author), NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA.
EM timothy.f.kennedy@nasa.gov
NR 29
TC 72
Z9 73
U1 1
U2 17
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 APR
PY 2009
VL 57
IS 4
BP 910
EP 918
DI 10.1109/TAP.2009.2014602
PG 9
WC Engineering, Electrical & Electronic; Telecommunications
SC Engineering; Telecommunications
GA 436TC
UT WOS:000265438000010
ER
PT J
AU Pan, B
Li, Y
Ponchak, GE
Papapolymerou, J
Tentzeris, MM
AF Pan, Bo
Li, Yuan
Ponchak, George E.
Papapolymerou, John
Tentzeris, Manos M.
TI A 60-GHz CPW-Fed High-Gain and Broadband Integrated Horn Antenna
SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
LA English
DT Article
DE Coplanar waveguide; integrated horn; micromachining; millimeter wave;
V-band
ID SUBMILLIMETER-WAVE APPLICATIONS; MILLIMETER-WAVE; FRONT-END; GUIDE; GHZ
AB An integrated horn antenna is presented for 60-GHz WPAN applications. Compared with other types of antenna for 60-GHz WPAN applications, an integrated horn antenna features wide bandwidth and high gain. This integrated H-plane horn is elevated on the top of the substrate using CMOS-compatible microfabrication steps. Antenna efficiency is greatly improved after eliminating dielectric loss. This antenna is excited using an integrated vertical current probe connected with a coplanar-wave-guide (CPW) by surface micromachining technologies. The lower part of the horn is constructed by rows of metallized pillars. The upper part and the top wall are built by stacking two layers of micromachined silicon wafers. The horn bottom is formed by metalizing the substrate's top surface. A prototype antenna is designed, fabricated, and characterized. Simulation and measurement results have shown wide input matching bandwidth and radiation bandwidth. The measured radiation pattern agrees well with the simulated one, demonstrating a gain as high as 14.6 dBi.
C1 [Li, Yuan; Papapolymerou, John; Tentzeris, Manos M.] Georgia Inst Technol, GEDC, Atlanta, GA 30332 USA.
[Ponchak, George E.] NASA, Glenn Res Ctr, Cleveland, OH 44135 USA.
RP Pan, B (reprint author), Wion Res, Realtek Semicond, Irvine, CA 92618 USA.
EM bo.pan@ieee.org; papapol@ece.gatech.edu
NR 23
TC 46
Z9 46
U1 0
U2 3
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 APR
PY 2009
VL 57
IS 4
BP 1050
EP 1056
DI 10.1109/TAP.2009.2015815
PG 7
WC Engineering, Electrical & Electronic; Telecommunications
SC Engineering; Telecommunications
GA 463BU
UT WOS:000267404200005
ER
PT J
AU Kerola, DX
Bruegge, CJ
Gross, HN
Helmlinger, MC
AF Kerola, Dana Xavier
Bruegge, Carol J.
Gross, Harry N.
Helmlinger, Mark C.
TI On-Orbit Calibration of the EO-1 Hyperion and Advanced Land Imager (ALI)
Sensors Using the LED Spectrometer (LSpec) Automated Facility
SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
LA English
DT Article
DE Atmospheric measurements; calibration; remote sensing
ID ANGLE IMAGING SPECTRORADIOMETER; MISR
AB Vicarious calibration (VC) technology, developed in the mid-1980s, has been employed to establish the absolute radiometric calibration of Earth-viewing sensors aboard satellites and aircraft. This method has heretofore required special visits by a field team to collect surface and atmospheric measurements, at specific times necessarily coincident with a sensor overflight. With the recent creation of an autonomous calibration facility, VC data can now be made available to the sensor community without the need for each research group to deploy its own field team. Beginning in mid-November 2006, there have been ongoing efforts to expand the data processing capabilities of the Jet Propulsion Laboratory-operated LED Spectrometer (LSpec) automatic facility, which has been making continual measurements of surface reflectances and atmospheric transmittances since that time. The facility is located at Frenchman Flat, within the Nevada Test Site. Data are used to support the VC of sensors which make observations at visible and near-infrared wavelengths. An array of eight LSpecs performs the autonomous function of recording surface reflectances at 5-min intervals, thereby permitting accurate and continual real-time adjustments to high-resolution Analytical Spectral Devices spectrometer measurements, acquired every several months during on-site visits. Moreover, resident at the LSpec site is a Cimel sunphotometer, used to make atmospheric transmittance measurements. The Cimel is part of the Aerosol Robotic Network (AERONET). Measurements made by the LSpec Cimel are used by AERONET to derive values of aerosol optical depths. From continuous in situ measurement of spectral reflectance of the playa surface, along with acquired aerosol optical depths and ozone optical depths (obtained from the Ozone Mapping Instrument), an LSpec database is being produced and is available via a web-based interface. To highlight the viability of making use of LSpec-derived data, we have executed a few distinct multiple scattering radiative transfer codes in order to perform VCs of the Earth Observing-1 (EO-1) Hyperion and EO-1 Advanced Land Imager sensors.
C1 [Kerola, Dana Xavier] Skillstorm Govt Integrated Serv, Pasadena, CA 91107 USA.
[Bruegge, Carol J.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
[Gross, Harry N.] Integrity Applicat Inc, Chantilly, VA 20151 USA.
[Helmlinger, Mark C.] Northrop Grumman Space Technol, Redondo Beach, CA 90278 USA.
RP Kerola, DX (reprint author), Skillstorm Govt Integrated Serv, Pasadena, CA 91107 USA.
EM Dina.X.Kerola@Jpl.Nasa.Gov; Carol.J.Bruegge@Jpl.Nasa.Gov;
hgross@integrity-apps.com; Mark.Helmlinger@ngc.com
NR 13
TC 15
Z9 17
U1 1
U2 5
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 APR
PY 2009
VL 47
IS 4
BP 1244
EP 1255
DI 10.1109/TGRS.2008.2008904
PG 12
WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote
Sensing; Imaging Science & Photographic Technology
SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science
& Photographic Technology
GA 425IM
UT WOS:000264630200024
ER
PT J
AU Wolff, R
Bhaduri, K
Kargupta, H
AF Wolff, Ran
Bhaduri, Kanishka
Kargupta, Hillol
TI A Generic Local Algorithm for Mining Data Streams in Large Distributed
Systems
SO IEEE TRANSACTIONS ON KNOWLEDGE AND DATA ENGINEERING
LA English
DT Article
DE Distributed data mining; peer-to-peer; local algorithms
AB In a large network of computers or wireless sensors, each of the components (henceforth, peers) has some data about the global state of the system. Much of the system's functionality such as message routing, information retrieval, and load sharing relies on modeling the global state. We refer to the outcome of the function (e. g., the load experienced by each peer) as the model of the system. Since the state of the system is constantly changing, it is necessary to keep the models up to date. Computing global data mining models, e. g., decision trees, k-means clustering in large distributed systems may be very costly due to the scale of the system and due to communication cost, which may be high. The cost further increases in a dynamic scenario when the data changes rapidly. In this paper, we describe a two-step approach for dealing with these costs. First, we describe a highly efficient local algorithm that can be used to monitor a wide class of data mining models. Then, we use this algorithm as a feedback loop for the monitoring of complex functions of the data such as its k-means clustering. The theoretical claims are corroborated with a thorough experimental analysis.
C1 [Wolff, Ran] Univ Haifa, Dept Management Informat Syst, IL-31905 Haifa, Israel.
[Bhaduri, Kanishka] NASA, Ames Res Ctr, Mission Crit Technol Inc, IDU Grp, Moffett Field, CA 94035 USA.
[Kargupta, Hillol] Univ Maryland, Dept Comp Sci & Elect Engn, Baltimore, MD 21250 USA.
[Kargupta, Hillol] AGNIK LLC, Columbia, MD 21045 USA.
RP Wolff, R (reprint author), Univ Haifa, Dept Management Informat Syst, IL-31905 Haifa, Israel.
EM rwolff@mis.haifa.il; kbhaduri@mail.arc.nasa.gov; hillol@cs.umbc.edu
FU US National Science Foundation CAREER Award [IIS-0093353]; NASA
[NNX07AV70G]
FX A preliminary version of this work was published in the Proceedings of
the 2006 SIAM Data Mining Conference (SDM '06). This work was done when
Kanishka Bhaduri was at UMBC. This research was supported by the US
National Science Foundation CAREER Award IIS-0093353 and NASA Grant
NNX07AV70G.
NR 25
TC 17
Z9 18
U1 0
U2 10
PU IEEE COMPUTER SOC
PI LOS ALAMITOS
PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA
SN 1041-4347
EI 1558-2191
J9 IEEE T KNOWL DATA EN
JI IEEE Trans. Knowl. Data Eng.
PD APR
PY 2009
VL 21
IS 4
BP 465
EP 478
DI 10.1109/TKDE.2008.169
PG 14
WC Computer Science, Artificial Intelligence; Computer Science, Information
Systems; Engineering, Electrical & Electronic
SC Computer Science; Engineering
GA 407WG
UT WOS:000263394400001
ER
PT J
AU Berg, MD
Label, KA
Kim, H
Friendlich, M
Phan, A
Perez, C
AF Berg, Melanie D.
LaBel, Kenneth A.
Kim, Hak
Friendlich, Mark
Phan, Anthony
Perez, Christopher
TI A Comprehensive Methodology for Complex Field Programmable Gate Array
Single Event Effects Test and Evaluation
SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE
LA English
DT Article
DE Evaluation; FPGA; scrubbing; Triple Mode Redundancy (TMR)
AB A methodology for evaluating various types of FPGAs targeted for space missions is presented. The premise is to supply unambiguous SEE information so that flight-projects may insert the optimal device for their application.
C1 [Berg, Melanie D.; LaBel, Kenneth A.; Kim, Hak; Friendlich, Mark; Phan, Anthony; Perez, Christopher] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
[Kim, Hak; Friendlich, Mark; Phan, Anthony; Perez, Christopher] MEI Technol, Lanham, MD 20706 USA.
RP Berg, MD (reprint author), NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
EM mdberg@pop500.gsfc.nasa.gov; kenneth.a.label@nasa.gov;
hak.s.kim@nasa.gov; mark.r.friendlich@nasa.gov; anthony.m.phan@nasa.gov;
christopher.e.perez@nasa.gov
NR 16
TC 9
Z9 9
U1 0
U2 2
PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
PI PISCATAWAY
PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA
SN 0018-9499
J9 IEEE T NUCL SCI
JI IEEE Trans. Nucl. Sci.
PD APR
PY 2009
VL 56
IS 2
BP 366
EP 374
DI 10.1109/TNS.2009.2013857
PG 9
WC Engineering, Electrical & Electronic; Nuclear Science & Technology
SC Engineering; Nuclear Science & Technology
GA 435WZ
UT WOS:000265375300001
ER
PT J
AU Sanmartin, JR
Charro, M
Lorenzini, EC
Garrett, HB
Bombardelli, C
Bramanti, C
AF Sanmartin, Juan R.
Charro, Mario
Lorenzini, Enrico C.
Garrett, Henry B.
Bombardelli, Claudio
Bramanti, Cristina
TI Electrodynamic Tether at Jupiter-II: Fast Moon Tour After Capture
SO IEEE TRANSACTIONS ON PLASMA SCIENCE
LA English
DT Article
DE Electrodynamic bare tether; Jovian mission design; planetary
exploration; propellantless space propulsion and power
AB An electrodynamic bare-tether mission to Jupiter, following the capture of a spacecraft (SC) into an equatorial highly elliptical orbit with perijove at about 1.3 times the Jovian radius, is discussed. Repeated applications of the propellantless Lorentz drag on a spinning tether, at the perijove vicinity, can progressively lower the apojove at constant perijove, for a tour of Galilean moons. Electrical energy is generated and stored as the SC moves from an orbit at 1: 1 resonance with a moon, down to resonance with the next moon; switching tether current off, stored power is then used as the SC makes a number of flybys of each moon. Radiation dose is calculated throughout the mission, during capture, flybys and moves between moons. The tour mission is limited by both power needs and accumulated dose. The three-stage apojove lowering down to Ganymede, Io, and Europa resonances would total less than 14 weeks, while 4 Ganymede, 20 Europa, and 16 Io flybys would add up to 18 weeks, with the entire mission taking just over seven months and the accumulated radiation dose keeping under 3 Mrad (Si) at 10-mm Al shield thickness.
C1 [Sanmartin, Juan R.; Charro, Mario] Univ Politecn Madrid, Dept Appl Phys, Sch Aeronaut Engn, E-28040 Madrid, Spain.
[Lorenzini, Enrico C.] Univ Padua, Dept Mech Engn, I-35100 Padua, Italy.
[Garrett, Henry B.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
[Bombardelli, Claudio; Bramanti, Cristina] European Space Agcy, Adv Concepts Team, European Space Res & Technol Ctr, NL-2200 AG Noordwijk, Netherlands.
RP Sanmartin, JR (reprint author), Univ Politecn Madrid, Dept Appl Phys, Sch Aeronaut Engn, E-28040 Madrid, Spain.
EM juanr.sanmartin@upm.es; mario.charro@upm.es; enrico.lorenzini@unipd.it
FU European Space Agency [19696/06]; Spanish Ministry of Science and
Technology [ESP2004-0151]
FX The works of J. R. Sanmartin and M. Charro were supported in part by the
European Space Agency under Contract 19696/06 and by the Spanish
Ministry of Science and Technology under Grant ESP2004-0151
NR 10
TC 13
Z9 13
U1 1
U2 2
PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
PI PISCATAWAY
PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA
SN 0093-3813
EI 1939-9375
J9 IEEE T PLASMA SCI
JI IEEE Trans. Plasma Sci.
PD APR
PY 2009
VL 37
IS 4
BP 620
EP 626
DI 10.1109/TPS.2009.2013955
PN 2
PG 7
WC Physics, Fluids & Plasmas
SC Physics
GA 435XK
UT WOS:000265376400013
ER
PT J
AU Mourikis, AI
Trawny, N
Roumeliotis, SI
Johnson, AE
Ansar, A
Matthies, L
AF Mourikis, Anastasios I.
Trawny, Nikolas
Roumeliotis, Stergios I.
Johnson, Andrew E.
Ansar, Adrian
Matthies, Larry
TI Vision-Aided Inertial Navigation for Spacecraft Entry, Descent, and
Landing
SO IEEE TRANSACTIONS ON ROBOTICS
LA English
DT Article; Proceedings Paper
CT Conference on Robotics - Science and Systems
CY JUN 26-30, 2007
CL Atlanta, GA
DE Descent and landing (EDL); entry; localization; sensor fusion; space
robotics; vision-aided inertial navigation
ID POSE ESTIMATION
AB In this paper, we present the vision-aided inertial navigation (VISINAV) algorithm that enables precision planetary landing. The vision front-end of the VISINAV system extracts 2-D-to-3-D correspondences between descent images and a surface map (mapped landmarks), as well as 2-D-to-2-D feature tracks through a sequence of descent images (opportunistic features). An extended Kalman filter (EKF) tightly integrates both types of visual feature observations with measurements from an inertial measurement unit. The filter computes accurate estimates of the lander's terrain-relative position, attitude, and velocity, in a resource-adaptive and hence real-time capable fashion. In addition to the technical analysis of the algorithm, the paper presents validation results from a sounding-rocket test flight, showing estimation errors of only 0.16 m/s for velocity and 6.4 m for position at touchdown. These results vastly improve current state of the art for terminal descent navigation without visual updates, and meet the requirements of future planetary exploration missions.
C1 [Mourikis, Anastasios I.] Univ Calif Riverside, Dept Elect Engn, Riverside, CA 92521 USA.
[Trawny, Nikolas; Roumeliotis, Stergios I.] Univ Minnesota, Dept Comp Sci & Engn, Minneapolis, MN 55455 USA.
[Johnson, Andrew E.; Ansar, Adrian; Matthies, Larry] CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA.
RP Mourikis, AI (reprint author), Univ Calif Riverside, Dept Elect Engn, Riverside, CA 92521 USA.
EM mourikis@ee.ucr.edu; trawny@cs.umn.edu; stergios@cs.umn.edu;
aej@jpl.nasa.gov; ansar@jpl.nasa.gov; lhm@jpl.nasa.gov
NR 48
TC 99
Z9 110
U1 3
U2 28
PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
PI PISCATAWAY
PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA
SN 1552-3098
EI 1941-0468
J9 IEEE T ROBOT
JI IEEE Trans. Robot.
PD APR
PY 2009
VL 25
IS 2
BP 264
EP 280
DI 10.1109/TRO.2008.2012342
PG 17
WC Robotics
SC Robotics
GA 435WA
UT WOS:000265372800005
ER
PT J
AU Vasavada, S
Sun, X
Ishii, M
Duval, W
AF Vasavada, S.
Sun, X.
Ishii, M.
Duval, W.
TI Benchmarking of the one-dimensional one-group interfacial area transport
equation for reduced-gravity bubbly flows
SO INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
LA English
DT Article
DE Liquid-liquid flow; Reduced gravity; Interfacial area; Coalescence;
Disintegration; Two-phase flow
ID BUOYANCY-DRIVEN MOTION; GAS-LIQUID FLOW; 2-PHASE FLOW; MICROGRAVITY
CONDITIONS; QUIESCENT LIQUID; VOID FRACTION; SLUG FLOW; COALESCENCE;
VELOCITY; MODEL
AB In order to properly design and safely operate two-phase flow systems, especially those deployed on future space missions, it is necessary to have accurate predictive capabilities. The application of a novel predictive method, the interfacial area transport equation (IATE), to dynamically predict the change of interfacial area concentration for reduced-gravity two-phase flows is described in this paper. Fluid particle interaction mechanisms such as coalescence and breakup that are present in reduced-gravity two-phase flows have been studied experimentally as reported in a previous paper by the current authors [Vasavada et al., 2007]. These mechanisms represent the source and sink terms in the IATE and their mechanistic models are benchmarked using experimental data obtained in a 25 mm inner diameter ground-based test section wherein reduced-gravity conditions were simulated. The comparison of the predictions from the model against experimental data shows good agreement. It has been found that, in contrast to the hypothesis extended in the literature, the wake entrainment based coalescence mechanism is present in reduced-gravity two-phase flows and in some cases is more important than coalescence due to random collision. Physics based arguments are extended to support this conclusion. (C) 2009 Elsevier Ltd. All rights reserved.
C1 [Vasavada, S.; Ishii, M.] Purdue Univ, Sch Nucl Engn, W Lafayette, IN 47907 USA.
[Sun, X.] Ohio State Univ, Dept Mech Engn, Columbus, OH 43210 USA.
[Duval, W.] NASA, Glenn Res Ctr, Fluid Phys & Transport Branch, Cleveland, OH 44135 USA.
RP Vasavada, S (reprint author), Energy Res Inc, 6189 Execut Blvd, Rockville, MD 20852 USA.
EM vasavad@purdue.edu; sxv@eri-world.com; ishii@purdue.edu;
Walter.M.Duval@grc.nasa.gov
RI Sun, Xiaodong/F-3752-2015
OI Sun, Xiaodong/0000-0002-9852-160X
FU National Aeronautics and Space Administration (NASA); Office of
Biological and Physical Research [NNC04GA26G]; NASA Glenn Research
Center, Cleveland, OH; En'urga Inc.; West Lafayette, IN
FX This work was supported by the National Aeronautics and Space
Administration (NASA), Office of Biological and Physical Research under
grant NNC04GA26G administered by the NASA Glenn Research Center,
Cleveland, OH. The authors thank Dr. Fran Chiaramonte of the NASA Glenn
Reserach Center for his support of this work. The authors also
acknowledge Dr. Y. Mi of En'urga Inc., West Lafayette, IN for his help
with the instrumentation.
NR 43
TC 4
Z9 4
U1 0
U2 5
PU PERGAMON-ELSEVIER SCIENCE LTD
PI OXFORD
PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND
SN 0301-9322
J9 INT J MULTIPHAS FLOW
JI Int. J. Multiph. Flow
PD APR
PY 2009
VL 35
IS 4
BP 323
EP 334
DI 10.1016/j.ijmultiphaseflow.2009.01.006
PG 12
WC Mechanics
SC Mechanics
GA 435DH
UT WOS:000265323400003
ER
PT J
AU Gaidos, E
Marteinsson, V
Thorsteinsson, T
Johannesson, T
Runarsson, AR
Stefansson, A
Glazer, B
Lanoil, B
Skidmore, M
Han, S
Miller, M
Rusch, A
Foo, W
AF Gaidos, Eric
Marteinsson, Viggo
Thorsteinsson, Thorsteinn
Johannesson, Tomas
Runarsson, Arni Rafn
Stefansson, Andri
Glazer, Brian
Lanoil, Brian
Skidmore, Mark
Han, Sukkyun
Miller, Mary
Rusch, Antje
Foo, Wilson
TI An oligarchic microbial assemblage in the anoxic bottom waters of a
volcanic subglacial lake
SO ISME JOURNAL
LA English
DT Article
DE acetogenesis; anoxia; extreme environments; microbial diversity;
psychrophily; sulfide oxidation
ID RIBOSOMAL-RNA SEQUENCES; SP-NOV.; OLIGONUCLEOTIDE PROBES; GEN. NOV.;
PHYLOGENETIC ANALYSIS; SULFATE REDUCTION; ONLINE RESOURCE; COMB. NOV;
DEEP-SEA; COMMUNITY
AB In 2006, we sampled the anoxic bottom waters of a volcanic lake beneath the Vatnajokull ice cap (Iceland). The sample contained 5 x 10(5) cells per ml, and whole-cell fluorescent in situ hybridization (FISH) and PCR with domain-specific probes showed these to be essentially all bacteria, with no detectable archaea. Pyrosequencing of the V6 hypervariable region of the 16S ribosomal RNA gene, Sanger sequencing of a clone library and FISH-based enumeration of four major phylotypes revealed that the assemblage was dominated by a few groups of putative chemotrophic bacteria whose closest cultivated relatives use sulfide, sulfur or hydrogen as electron donors, and oxygen, sulfate or CO(2) as electron acceptors. Hundreds of other phylotypes are present at lower abundance in our V6 tag libraries and a rarefaction analysis indicates that sampling did not reach saturation, but FISH data limit the remaining biome to < 10-20% of all cells. The composition of this oligarchy can be understood in the context of the chemical disequilibrium created by the mixing of sulfidic lake water and oxygenated glacial meltwater.
C1 [Gaidos, Eric; Rusch, Antje] Univ Hawaii Manoa, Dept Geol & Geophys, Honolulu, HI 96822 USA.
[Gaidos, Eric] NASA, Astrobiol Inst, Mountain View, CA USA.
[Marteinsson, Viggo; Runarsson, Arni Rafn] MATIS Prokaria, Reykjavik, Iceland.
[Thorsteinsson, Thorsteinn] Natl Energy Author, Hydrol Serv, Reykjavik, Iceland.
[Johannesson, Tomas] Iceland Meteorol Off, Reykjavik, Iceland.
[Stefansson, Andri] Univ Iceland, Inst Sci, IS-107 Reykjavik, Iceland.
[Glazer, Brian] Univ Hawaii, Dept Oceanog, Honolulu, HI 96822 USA.
[Lanoil, Brian; Han, Sukkyun; Foo, Wilson] Univ Calif Riverside, Dept Environm Sci, Riverside, CA 92521 USA.
[Skidmore, Mark] Montana State Univ, Dept Earth Sci, Bozeman, MT 59717 USA.
[Miller, Mary] Univ Texas Med Branch, Dept Microbiol & Immunol, Galveston, TX USA.
RP Gaidos, E (reprint author), Univ Hawaii Manoa, Dept Geol & Geophys, 1680 East West Rd, Honolulu, HI 96822 USA.
EM gaidos@hawaii.edu
RI Glazer, Brian/C-2248-2011;
OI Rusch, Antje/0000-0001-8686-9433; Lanoil, Brian/0000-0001-8603-8330
FU National Aeronautics and Space Administration [NNA04CC08A]; Icelandic
Centre for Research
FX This material is based upon work supported by the National Aeronautics
and Space Administration through the NASA Astrobiology Institute under
Cooperative Agreement no. NNA04CC08A issued through the Office of Space
Science and by the Icelandic Centre for Research. The Icelandic National
Energy Authority, National Power Company and Public Roads Administration
provided logistical support. Members of the Icelandic Glaciological
Society assisted in the field campaign on Vatnajokull. The NAI lead team
at the Marine Biological Laboratory performed pyrosequencing, and Mitch
Sogin, Hilary Morrison and Sue Huse assisted with procedures and
analysis. Ruth Richardson provided an enrichment culture for FISH. Brian
Popp and Terri Rust measured POM.
NR 70
TC 22
Z9 23
U1 1
U2 24
PU NATURE PUBLISHING GROUP
PI NEW YORK
PA 75 VARICK ST, 9TH FLR, NEW YORK, NY 10013-1917 USA
SN 1751-7362
J9 ISME J
JI ISME J.
PD APR
PY 2009
VL 3
IS 4
BP 486
EP 497
DI 10.1038/ismej.2008.124
PG 12
WC Ecology; Microbiology
SC Environmental Sciences & Ecology; Microbiology
GA 427LP
UT WOS:000264781100010
PM 19092861
ER
PT J
AU Fleurial, JP
AF Fleurial, Jean-Pierre
TI Thermoelectric Power Generation Materials: Technology and Application
Opportunities
SO JOM
LA English
DT Article
ID THERMAL-CONDUCTIVITY; EFFICIENCY; DEVICES; ALLOYS
AB Thermoelectric power sources have consistently demonstrated their extraordinary reliability and longevity for deep space missions (67 missions to date, more than 30 years of life) as well as terrestrial applications where unattended operation in remote locations is required. The development of new, more efficient materials and devices is the key to improving existing space power technology and expanding the range of terrestrial applications. The NASA Jet Propulsion Laboratory is leading collaborative research and development on novel advanced bulk materials capable of long-term operation at temperatures up to 1,300 K at more than 20% conversion efficiency. The research areas include refractory rare earth compounds and bulk three-dimensional nanostructures that emulate results obtained on low dimensional superlattices through "force engineering" and "self-assembling" techniques. Recent experimental results will be highlighted, and progress in transitioning thermoelectric technology to a more flexible, lower-cost modular array configuration suitable for various application opportunities will be discussed.
C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
RP Fleurial, JP (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,MS 277-207, Pasadena, CA 91109 USA.
EM jean-pierre.fleurial@jpl.nasa.gov
NR 29
TC 34
Z9 34
U1 5
U2 26
PU SPRINGER
PI NEW YORK
PA 233 SPRING ST, NEW YORK, NY 10013 USA
SN 1047-4838
EI 1543-1851
J9 JOM-US
JI JOM
PD APR
PY 2009
VL 61
IS 4
BP 79
EP 85
PG 7
WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical
Engineering; Mineralogy; Mining & Mineral Processing
SC Materials Science; Metallurgy & Metallurgical Engineering; Mineralogy;
Mining & Mineral Processing
GA 445GK
UT WOS:000266038200014
ER
PT J
AU Dresselhaus, MS
Chen, G
Ren, ZF
Dresselhaus, G
Henry, A
Fleurial, JP
AF Dresselhaus, M. S.
Chen, G.
Ren, Z. F.
Dresselhaus, G.
Henry, A.
Fleurial, J. -P.
TI New Composite Thermoelectric Materials for Energy Harvesting
Applications
SO JOM
LA English
DT Article
ID BULK ALLOYS; PERFORMANCE; FIGURE; MERIT
AB The concept of using nanostructured composite materials to enhance the dimensionless thermoelectric figure of merit ZT relative to that for their counterpart homogeneous alloyed bulk crystalline materials of similar chemical composition is presented in general terms. Specific applications are made to the Si-Ge and Bi (2-x)Sb(x)Te(3) systems for use in high-temperature power generation and cooling applications. The scientific advantages of the nanocomposite approach for the simultaneous increase in the power factor and decrease in the thermal conductivity are emphasized insofar as their simultaneous occurrence is enabled by the independent control of these physical properties through the special properties of their nanostructures. Also emphasized are the practical advantages of using such bulk samples both for thermoelectric property measurements and for providing a straightforward path to scaling up the materials synthesis and integration of such nanostructured materials into practical thermoelectric power-generation and cooling modules and devices.
C1 [Dresselhaus, M. S.; Chen, G.; Dresselhaus, G.; Henry, A.] MIT, Cambridge, MA 02139 USA.
[Ren, Z. F.] Boston Coll, Chestnut Hill, MA 02467 USA.
[Fleurial, J. -P.] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
RP Dresselhaus, MS (reprint author), MIT, 77 Massachusetts Ave, Cambridge, MA 02139 USA.
EM millie@mgm.mit.edu
RI Ren, Zhifeng/B-4275-2014; Chen, Gang/J-1325-2014
OI Chen, Gang/0000-0002-3968-8530
FU U.S. Department of Energy [DE-FG02-08ER46516]
FX The authors gratefully acknowledge the assistance of Mario Hofmann for
help with the preparation of the figures. MSD, GC, and ZR acknowledge
support for this work under U.S. Department of Energy BES Grant
DE-FG02-08ER46516. Part of this work was performed at the Jet Propulsion
Laboratory/California Institute of Technology under contract with NASA.
NR 15
TC 29
Z9 29
U1 4
U2 38
PU SPRINGER
PI NEW YORK
PA 233 SPRING ST, NEW YORK, NY 10013 USA
SN 1047-4838
J9 JOM-US
JI JOM
PD APR
PY 2009
VL 61
IS 4
BP 86
EP 90
PG 5
WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical
Engineering; Mineralogy; Mining & Mineral Processing
SC Materials Science; Metallurgy & Metallurgical Engineering; Mineralogy;
Mining & Mineral Processing
GA 445GK
UT WOS:000266038200015
ER
PT J
AU Miele, A
Ciarcia, M
Weeks, MW
AF Miele, A.
Ciarcia, M.
Weeks, M. W.
TI Rendezvous Guidance Trajectories via Multiple-Subarc Sequential
Gradient-Restoration Algorithm
SO JOURNAL OF AEROSPACE ENGINEERING
LA English
DT Article
AB We consider the three-dimensional rendezvous between a target spacecraft in a circular orbit and a chaser spacecraft with an initial separation distance and an initial separation velocity. We assume that the chaser spacecraft has variable mass and that its trajectory is governed by three controls, one determining the thrust magnitude and two determining the thrust direction. We employ the Clohessy-Wiltshire equations, describing the relative motion of the chaser vis-a-vis the target, and the multiple-subarc sequential gradient-restoration algorithm to produce first optimal trajectories and then guidance trajectories for the following problems: P1-minimum time, fuel free; P2-minimum fuel, time free; P3-minimum time, fuel given; P4-minimum fuel, time given; and P5-minimum timexfuel, time and fuel free. Clearly, P1 and P2 are basic problems, while P3, P4, and P5 are compromise problems. Problem P1 leads to a two-subarc solution including a max-thrust subarc followed by another max-thrust subarc. Problem P2 leads to a four-subarc solution including two coasting subarcs alternating with two max-thrust subarcs. Problems P5 leads to a three-subarc solution including two max-thrust subarcs alternating with one coasting subarc. Problems P3 and P4 include P1, P2, and P5 as particular cases and lead to two-, three-, or four-subarcs solutions depending on the prescribed value of fuel or time. For all problems, the thrust magnitude control is saturated at one of its extreme values: in optimization studies, we determine the best thrust direction controls; in guidance studies, we force the thrust direction controls to be constant in each subarc and determine the best thrust direction parameters. Of course, the time lengths of all the subarcs must also be determined. The computational results show that, for Problems P1-P5, the performance index of the multiple-subarc guidance trajectory approximates well the performance index of the multiple-subarc optimal trajectory: the pairwise relative differences in performance index are less than 1/100 in all cases. To sum up, the produced guidance trajectories are highly efficient and yet quite simple in implementation.
C1 [Miele, A.; Ciarcia, M.] Rice Univ, Houston, TX 77005 USA.
[Weeks, M. W.] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77005 USA.
RP Miele, A (reprint author), Rice Univ, Houston, TX 77005 USA.
EM michael.w.weeks@nasa.gov; ciarcia@rice.edu; michael.w.weeks@nasa.gov
NR 11
TC 0
Z9 0
U1 1
U2 2
PU ASCE-AMER SOC CIVIL ENGINEERS
PI RESTON
PA 1801 ALEXANDER BELL DR, RESTON, VA 20191-4400 USA
SN 0893-1321
J9 J AEROSPACE ENG
JI J. Aerosp. Eng.
PD APR
PY 2009
VL 22
IS 2
BP 160
EP 172
DI 10.1061/(ASCE)0893-1321(2009)22:2(160)
PG 13
WC Engineering, Aerospace; Engineering, Civil
SC Engineering
GA 418MK
UT WOS:000264152100007
ER
PT J
AU Liao, L
Meneghini, R
AF Liao, Liang
Meneghini, Robert
TI Validation of TRMM Precipitation Radar through Comparison of Its
Multiyear Measurements with Ground-Based Radar
SO JOURNAL OF APPLIED METEOROLOGY AND CLIMATOLOGY
LA English
DT Article
ID MEASURING MISSION TRMM; SIZE; SATELLITE; PARAMETERS; MODEL; SHAPE; SITE
AB A procedure to accurately resample spaceborne and ground-based radar data is described and then is applied to the measurements taken from the Tropical Rainfall Measuring Mission (TRMM) precipitation radar (PR) and the ground-based Weather Surveillance Radar-1988 Doppler (WSR-88D or WSR) for the validation of the PR measurements and estimates. Through comparisons with the well-calibrated, non-attenuated WSR at Melbourne, Florida, for the period 1998-2007, the calibration of the PR aboard the TRMM satellite is checked using measurements near the storm top. Analysis of the results indicates that the PR, after taking into account differences in radar reflectivity factors between the PR and WSR, has a small positive bias of 0.8 dB relative to the WSR, implying a soundness of the PR calibration in view of the uncertainties involved in the comparisons. Comparisons between the PR and WSR reflectivities are also made near the surface for evaluation of the attenuation-correction procedures used in the PR algorithms. It is found that the PR attenuation is accurately corrected in stratiform rain but is underestimated in convective rain, particularly in heavy rain. Tests of the PR estimates of rainfall rate are conducted through comparisons in the overlap area between the TRMM overpass and WSR scan. Analyses of the data are made both on a conditional basis, in which the instantaneous rain rates are compared only at those pixels at which both the PR and WSR detect rain, and an unconditional basis, in which the area-averaged rain rates are estimated independently for the PR and WSR. Results of the conditional rain comparisons show that the PR-derived rain is about 9% greater and 19% less than the WSR estimates for stratiform and convective storms, respectively. Overall, the PR tends to underestimate the conditional mean rain rate by 8% for all rain categories, a finding that conforms to the results of the area-averaged rain (unconditional) comparisons.
C1 [Liao, Liang] UMBC, Goddard Earth Sci & Technol Ctr, Greenbelt, MD 20771 USA.
[Meneghini, Robert] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA.
RP Liao, L (reprint author), UMBC, Goddard Earth Sci & Technol Ctr, Code 614-6, Greenbelt, MD 20771 USA.
EM liang.liao-1@nasa.gov
FU NASA's Precipitation Measurement Mission (PMM) [NNH06ZDA001N-PMM]
FX We thank David Wolff, David Marks, and the Goddard Space Flight Center
TRMM office for providing ground-based WSR data. This work is supported
by Dr. R. Kakar of NASA Headquarters under NASA's Precipitation
Measurement Mission (PMM) Grant NNH06ZDA001N-PMM.
NR 28
TC 20
Z9 21
U1 0
U2 0
PU AMER METEOROLOGICAL SOC
PI BOSTON
PA 45 BEACON ST, BOSTON, MA 02108-3693 USA
SN 1558-8424
J9 J APPL METEOROL CLIM
JI J. Appl. Meteorol. Climatol.
PD APR
PY 2009
VL 48
IS 4
BP 804
EP 817
DI 10.1175/2008JAMC1974.1
PG 14
WC Meteorology & Atmospheric Sciences
SC Meteorology & Atmospheric Sciences
GA 443EQ
UT WOS:000265893400008
ER
PT J
AU Nehrir, AR
Repasky, KS
Carlsten, JL
Obland, MD
Shaw, JA
AF Nehrir, Amin R.
Repasky, Kevin S.
Carlsten, John L.
Obland, Michael D.
Shaw, Joseph A.
TI Water Vapor Profiling Using a Widely Tunable, Amplified
Diode-Laser-Based Differential Absorption Lidar (DIAL)
SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY
LA English
DT Article
ID RAMAN LIDAR; DYE-LASER; TEMPERATURE; AIRBORNE; PERFORMANCE; RESOLUTION;
AEROSOL
AB A differential absorption lidar (DIAL) instrument for automated profiling of water vapor in the lower troposphere has been designed, tested, and is in routine operation at Montana State University. The laser transmitter for the DIAL instrument uses a widely tunable external cavity diode laser (ECDL) to injection seed two cascaded semiconductor optical amplifiers (SOAs) to produce a laser transmitter that accesses the 824-841-nm spectral range. The DIAL receiver utilizes a 28-cm-diameter Schmidt-Cassegrain telescope; an avalanche photodiode (APD) detector; and a narrowband optical filter to collect, discriminate, and measure the scattered light. A technique of correcting for the wavelength-dependent incident angle upon the narrowband optical filter as a function of range has been developed to allow accurate water vapor profiles to be measured down to 225 m above the surface. Data comparisons using the DIAL instrument and collocated radiosonde measurements are presented demonstrating the capabilities of the DIAL instrument.
C1 [Nehrir, Amin R.; Repasky, Kevin S.; Shaw, Joseph A.] Montana State Univ, Dept Elect & Comp Engn, Bozeman, MT 59717 USA.
[Carlsten, John L.; Obland, Michael D.] Montana State Univ, Dept Phys, Bozeman, MT 59717 USA.
[Obland, Michael D.] NASA, Langley Res Ctr, SSAI, Hampton, VA 23665 USA.
RP Repasky, KS (reprint author), Montana State Univ, Dept Elect & Comp Engn, Cobleigh Hall,Room 610, Bozeman, MT 59717 USA.
EM repasky@ece.montana.edu
FU NASA [NNX06AD11G]
FX This work was supported by NASA Grant NNX06AD11G. Partial support was
also provided by the NASA Graduate Student Researchers Program (GSRP).
NR 32
TC 19
Z9 19
U1 0
U2 2
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 APR
PY 2009
VL 26
IS 4
BP 733
EP 745
DI 10.1175/2008JTECHA1201.1
PG 13
WC Engineering, Ocean; Meteorology & Atmospheric Sciences
SC Engineering; Meteorology & Atmospheric Sciences
GA 443ZN
UT WOS:000265949400005
ER
PT J
AU Willis, JK
Lyman, JM
Johnson, GC
Gilson, J
AF Willis, Josh K.
Lyman, John M.
Johnson, Gregory C.
Gilson, John
TI In Situ Data Biases and Recent Ocean Heat Content Variability
SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY
LA English
DT Article
ID T-5 EXPENDABLE BATHYTHERMOGRAPH; SEA-LEVEL RISE; ALTIMETRIC HEIGHT;
STERIC HEIGHT; FALL-RATE; TOPEX/POSEIDON; TEMPERATURE; CIRCULATION;
EQUATION; PACIFIC
AB Two significant instrument biases have been identified in the in situ profile data used to estimate globally integrated upper-ocean heat content. A large cold bias was discovered in a small fraction of Argo floats along with a smaller but more prevalent warm bias in expendable bathythermograph (XBT) data. These biases appear to have caused the bulk of the upper-ocean cooling signal reported by Lyman et al. between 2003 and 2005. These systematic data errors are significantly larger than sampling errors in recent years and are the dominant sources of error in recent estimates of globally integrated upper-ocean heat content variability. The bias in the XBT data is found to be consistent with errors in the fall-rate equations, suggesting a physical explanation for that bias. With biased profiles discarded, no significant warming or cooling is observed in upper-ocean heat content between 2003 and 2006.
C1 [Willis, Josh K.] CALTECH, Jet Prop Lab, Pasadena, CA 90034 USA.
[Lyman, John M.; Johnson, Gregory C.] NOAA, Pacific Marine Environm Lab, Seattle, WA 98115 USA.
[Lyman, John M.] Univ Hawaii Manoa, JIMAR, Honolulu, HI 96822 USA.
[Gilson, John] Univ Calif San Diego, Scripps Inst Oceanog, La Jolla, CA 92093 USA.
RP Willis, JK (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr,M-S 300-323, Pasadena, CA 90034 USA.
EM joshua.k.willis@jpl.nasa.gov
RI Johnson, Gregory/I-6559-2012
OI Johnson, Gregory/0000-0002-8023-4020
NR 21
TC 42
Z9 43
U1 0
U2 8
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 APR
PY 2009
VL 26
IS 4
BP 846
EP 852
DI 10.1175/2008JTECHO608.1
PG 7
WC Engineering, Ocean; Meteorology & Atmospheric Sciences
SC Engineering; Meteorology & Atmospheric Sciences
GA 443ZN
UT WOS:000265949400015
ER
PT J
AU Liu, P
Kajikawa, Y
Wang, B
Kitoh, A
Yasunari, T
Li, T
Annamalai, H
Fu, XH
Kikuchi, K
Mizuta, R
Rajendran, K
Waliser, DE
Kim, D
AF Liu, Ping
Kajikawa, Yoshiyuki
Wang, Bin
Kitoh, Akio
Yasunari, Tetsuzo
Li, Tim
Annamalai, H.
Fu, Xiouhua
Kikuchi, Kazuyoshi
Mizuta, Ryo
Rajendran, Kavirajan
Waliser, Duane E.
Kim, Daehyun
TI Tropical Intraseasonal Variability in the MRI-20km60L AGCM
SO JOURNAL OF CLIMATE
LA English
DT Article
ID MADDEN-JULIAN OSCILLATION; GENERAL-CIRCULATION MODELS; ASIAN SUMMER
MONSOON; LARGE-SCALE MODELS; CONVECTION PARAMETERIZATION; VERTICAL
STRUCTURE; LIFE-CYCLE; PART II; SCHEME; SIMULATION
AB This study documents the detailed characteristics of the tropical intraseasonal variability (TISV) in the MRI-20km60L AGCM that uses a variant of the Arakawa-Schubert cumulus parameterization. Mean states, power spectra, propagation features, leading EOF modes, horizontal and vertical structures, and seasonality associated with the TISV are analyzed. Results show that the model reproduces the mean states in winds realistically and in convection comparable to that of the observations. However, the simulated TISV is less realistic. It shows low amplitudes in convection and low-level winds in the 30-60-day band. Filtered anomalies have standing structures. Power spectra and lag correlation of the signals do not propagate dominantly either in the eastward direction during boreal winter or in the northward direction during boreal summer. A combined EOF (CEOF) analysis shows that winds and convection have a loose coupling that cannot sustain the simulated TISV as realistically as that observed. In the composited mature phase of the simulated MJO, the low-level convergence does not lead convection clearly so that the moisture anomalies do not tilt westward in the vertical, indicating that the low-level convergence does not favor the eastward propagation. The less realistic TISV suggests that the representation of cumulus convection needs to be improved in this model.
C1 [Liu, Ping; Kajikawa, Yoshiyuki; Wang, Bin; Li, Tim; Annamalai, H.; Fu, Xiouhua; Kikuchi, Kazuyoshi] Univ Hawaii Manoa, Int Pacific Res Ctr, SOEST, Honolulu, HI 96822 USA.
[Kitoh, Akio] Met Res Inst, Tsukuba, Ibaraki, Japan.
[Yasunari, Tetsuzo] Japan Agcy Marine Earth Sci & Technol, Frontier Res Ctr Global Change, Kanagawa, Japan.
[Mizuta, Ryo] Meteorol Res Inst, Adv Earth Sci & Technol Org, Tsukuba, Ibaraki 305, Japan.
[Rajendran, Kavirajan] Natl Aerosp Labs, Ctr Math Modelling & Comp Simulat, Bangalore, Karnataka, India.
[Waliser, Duane E.] CALTECH, Jet Prop Lab, Pasadena, CA USA.
[Kim, Daehyun] Seoul Natl Univ, Sch Earth & Environm Sci, Seoul, South Korea.
RP Liu, P (reprint author), Univ Hawaii Manoa, Int Pacific Res Ctr, SOEST, 1680 East West Rd, Honolulu, HI 96822 USA.
EM pliu@hawaii.edu
RI Rajendran, Kavirajan/C-3334-2009; CMMACS, CSIR/A-2491-2011; Kikuchi,
Kazuyoshi/C-2744-2009; Kajikawa, Yoshiyuki/C-2807-2009
OI Rajendran, Kavirajan/0000-0002-9437-4729; Kikuchi,
Kazuyoshi/0000-0002-6200-0968;
FU Japan Agency of Marine Science and Technology (JAMESTEC); NASA
[NNX07AG53G]; International Pacific Research Center (IPRC); Jet
Propulsion Laboratory; National Aeronautics and Space Administration
FX This study is supported by the Japan Agency of Marine Science and
Technology (JAMESTEC) and NASA Grant NNX07AG53G through their
sponsorship of the International Pacific Research Center (IPRC). D.
Waliser was supported by the Jet Propulsion Laboratory under a contract
with the National Aeronautics and Space Administration. We thank the U.
S. CLIVAR MJO Working Group for providing the software package. We also
thank Diane Henderson and three reviewers for their comments.
NR 57
TC 12
Z9 13
U1 0
U2 3
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 APR
PY 2009
VL 22
IS 8
BP 2006
EP 2022
DI 10.1175/2008JCLI2406.1
PG 17
WC Meteorology & Atmospheric Sciences
SC Meteorology & Atmospheric Sciences
GA 444TH
UT WOS:000266002800008
ER
PT J
AU Wu, MLC
Schubert, SD
Suarez, MJ
Huang, NE
AF Wu, Man-Li C.
Schubert, Siegfried D.
Suarez, Max J.
Huang, Norden E.
TI An Analysis of Moisture Fluxes into the Gulf of California
SO JOURNAL OF CLIMATE
LA English
DT Article
ID NORTH-AMERICAN-MONSOON; PACIFIC TROPICAL CYCLOGENESIS; SOUTHWESTERN
UNITED-STATES; MADDEN-JULIAN OSCILLATION; EASTERN PACIFIC; HILBERT
SPECTRUM; ARIZONA MONSOON; SURGES; WAVES; SUMMER
AB This study examines the nature of episodes of enhanced warm-season moisture flux into the Gulf of California. Both spatial structure and primary time scales of the fluxes are examined using the 40-yr ECMWF Re-Analysis data for the period 1980-2001. The analysis approach consists of a compositing technique that is keyed on the low-level moisture fluxes into the Gulf of California. The results show that the fluxes have a rich spectrum of temporal variability, with periods of enhanced transport over the gulf linked to African easterly waves on subweekly (3-8 day) time scales, the Madden-Julian oscillation (MJO) at intraseasonal time scales (20-90 day), and intermediate (10-15 day) time-scale disturbances that appear to originate primarily in the Caribbean Sea-western Atlantic Ocean.
In the case of the MJO, enhanced low-level westerlies and large-scale rising motion provide an environment that favors large-scale cyclonic development near the west coast of Central America that, over the course of about 2 weeks, expands northward along the coast eventually reaching the mouth of the Gulf of California where it acts to enhance the southerly moisture flux in that region. On a larger scale, the development includes a northward shift in the eastern Pacific ITCZ, enhanced precipitation over much of Mexico and the southwestern United States, and enhanced southerly/southeasterly fluxes from the Gulf of Mexico into Mexico and the southwestern and central United States. In the case of the easterly waves, the systems that reach Mexico appear to redevelop/ reorganize on the Pacific coast and then move rapidly to the northwest to contribute to the moisture flux into the Gulf of California. The most intense fluxes into the gulf on these time scales appear to be synchronized with a midlatitude short-wave trough over the U. S. West Coast and enhanced low-level southerly fluxes over the U. S. Great Plains. The intermediate (10-15 day) time-scale systems have zonal wavelengths roughly twice that of the easterly waves, and their initiation appears to be linked to an extratropical U. S. East Coast ridge and associated northeasterly winds that extend well into the Caribbean Sea during their development phase. The short (3-8 day) and, to a lesser extent, the intermediate (10-15 day) time-scale fluxes tend to be enhanced when the convectively active phase of the MJO is situated over the Americas.
C1 [Wu, Man-Li C.; Schubert, Siegfried D.; Suarez, Max J.; Huang, Norden E.] NASA, Goddard Space Flight Ctr, Earth Sci Directorate, Greenbelt, MD 20771 USA.
RP Huang, NE (reprint author), NASA GSFC GMAO, 8800 Greenbelt Rd, Greenbelt, MD 20771 USA.
EM man-li.c.wu@nasa.gov
FU National Research Council, Taiwan [95-2119-M-008-031-MY3]
FX This work was supported by the NASA Earth Science Enterprises' Global
Modeling and Analysis Program. However, Dr. Norden E. Huang is supported
in part by a grant from National Research Council, Taiwan ( NSC
95-2119-M-008-031-MY3).
NR 39
TC 10
Z9 12
U1 0
U2 3
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 APR
PY 2009
VL 22
IS 8
BP 2216
EP 2239
DI 10.1175/2008JCLI2525.1
PG 24
WC Meteorology & Atmospheric Sciences
SC Meteorology & Atmospheric Sciences
GA 444TH
UT WOS:000266002800020
ER
PT J
AU Volz, MP
Mazuruk, K
Aggarwal, MD
Croll, A
AF Volz, M. P.
Mazuruk, K.
Aggarwal, M. D.
Croell, A.
TI Interface shape control using localized heating during Bridgman growth
SO JOURNAL OF CRYSTAL GROWTH
LA English
DT Article
DE Computer simulation; Convection; Heat transfer; Interfaces; Bridgman
technique
ID CRYSTAL-GROWTH; STOCKBARGER TECHNIQUE; CONFIGURATION; FURNACE
AB Numerical calculations were performed to assess the effect of localized radial heating on the melt-crystal interface shape during vertical Bridgman growth. System parameters examined include the ampoule, melt and crystal thermal conductivities, the magnitude and width of localized heating, and the latent heat of crystallization. Concave interface shapes, typical of semiconductor systems, could be flattened or made convex with localized heating. Although localized heating caused shallower thermal gradients ahead of the interface, the magnitude of the localized heating required for convexity was less than that which resulted in a thermal inversion ahead of the interface. A convex interface shape was most readily achieved with ampoules of lower thermal conductivity. Increasing melt convection tended to flatten the interface, but the amount of radial heating required to achieve a convex interface was essentially independent of the convection intensity. (C) 2009 Elsevier B.V. All rights reserved.
C1 [Volz, M. P.] NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA.
[Mazuruk, K.] Univ Alabama, Huntsville, AL 35899 USA.
[Aggarwal, M. D.] Alabama A&M Univ, Dept Phys, Normal, AL 35762 USA.
[Croell, A.] Univ Freiburg, Inst Kristallog, D-79104 Freiburg, Germany.
RP Volz, MP (reprint author), NASA, George C Marshall Space Flight Ctr, EM30, Huntsville, AL 35812 USA.
EM Martin.Volz@nasa.gov
RI Croell, Arne/A-2480-2013
OI Croell, Arne/0000-0002-8673-9994
NR 12
TC 8
Z9 8
U1 0
U2 7
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0022-0248
J9 J CRYST GROWTH
JI J. Cryst. Growth
PD APR 1
PY 2009
VL 311
IS 8
BP 2321
EP 2326
DI 10.1016/j.jcrysgro.2009.02.019
PG 6
WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied
SC Crystallography; Materials Science; Physics
GA 449SZ
UT WOS:000266351600016
ER
PT J
AU Fong, T
Nagatani, K
Wettergreen, D
AF Fong, Terrence
Nagatani, Keiji
Wettergreen, David
TI EDITORIAL: Space Robotics, Part II
SO JOURNAL OF FIELD ROBOTICS
LA English
DT Editorial Material
C1 [Fong, Terrence] NASA, Ames Res Ctr, Washington, DC 20546 USA.
[Nagatani, Keiji] Tohoku Univ, Sendai, Miyagi 980, Japan.
[Wettergreen, David] Carnegie Mellon Univ, Pittsburgh, PA 15213 USA.
RP Fong, T (reprint author), NASA, Ames Res Ctr, Washington, DC 20546 USA.
NR 0
TC 0
Z9 0
U1 0
U2 2
PU JOHN WILEY & SONS INC
PI HOBOKEN
PA 111 RIVER ST, HOBOKEN, NJ 07030 USA
SN 1556-4959
J9 J FIELD ROBOT
JI J. Field Robot.
PD APR
PY 2009
VL 26
IS 4
BP 335
EP 336
DI 10.1002/rob.20298
PG 2
WC Robotics
SC Robotics
GA 421HH
UT WOS:000264349500001
ER
PT J
AU Carsten, J
Rankin, A
Ferguson, D
Stentz, A
AF Carsten, Joseph
Rankin, Arturo
Ferguson, Dave
Stentz, Anthony
TI Global Planning on the Mars Exploration Rovers: Software Integration and
Surface Testing
SO JOURNAL OF FIELD ROBOTICS
LA English
DT Article
AB In January 2004, NASA!s twin Mars Exploration Rovers (MERs), Spirit and Opportunity, began searching the surface of Mars for evidence of past water activity. To locatize and approach scientifically interesting targets, the rovers employ an onboard navigation system. Given the latency in sending commands from Earth to the Martian rovers (and in receiving return data), a high level of navigational autonomy is desirable. Autonomous navigation with hazard avoidance (AutoNav) is currently performed using a local path planner called GESTALT (grid-based estimation of surface traversability applied to local terrain) that incorporates terrain and obstacle information generated from stereo cameras. GESTALT works well at guiding the rovers around narrow and isolated hazards; however, it is susceptible to failure when clusters of closely spaced, non traversable rocks form extended obstacles. In May 2005, a new technology task was initiated at the jet Propulsion Laboratory to address this limitation. Specifically, a version of the Field D* global path planner was integrated into MER flight software, enabling simultaneous local and global planning during AutoNav. A revised version of AutoNav was then uploaded to the rovers during the summer of 2006. In this paper we describe how this integration of global planning into the MER flight software was performed and provide results from both the MER surface system test bed rover and five fully autonomous runs by Opportunity on Mars. (C) 2009 Wiley Periodicals, Inc.
C1 [Carsten, Joseph; Rankin, Arturo] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA.
[Ferguson, Dave] Intel Res Pittsburgh, Pittsburgh, PA 15213 USA.
[Stentz, Anthony] Carnegie Mellon Univ, Inst Robot, Pittsburgh, PA 15213 USA.
RP Carsten, J (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA.
EM joseph.carsten@jpl.nasa.gov; arturo.rankin@jpl.nasa.gov;
dave.ferguson@intel.com; tony@cmu.edu
FU MER; Mars Technology Program (MTP)
FX The research described in this paper was performed at the Jet Propulsion
Laboratory (JPL), California Institute of Technology, under a contract
with the National Aeronautics and Space Administration (contract
NAS7-03001) and at Carnegie Mellon University (CMU) under a contract
with the JPL (contract 1263676). This research was funded by the MER
project and the Mars Technology Program (MTP) under task order
NM0710764. CMU configured Field D* for MER and provided it to JPL under
a research license with the California Institute of Technology, and JPL
integrated Field D* into the MER flight software. CMU's work was
performed under the MTP Reliable and Efficient Long-Range Autonomous
Rover Navigation task, and JPUs work was performed under the MTP D*
Integration into MER task. The authors would like to thank Mark Maimone
for his sage advice during the integration and testing process. Without
his assistance this process would have been infinitely more difficult.
NR 16
TC 18
Z9 18
U1 0
U2 5
PU WILEY-BLACKWELL
PI HOBOKEN
PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA
SN 1556-4959
EI 1556-4967
J9 J FIELD ROBOT
JI J. Field Robot.
PD APR
PY 2009
VL 26
IS 4
SI SI
BP 337
EP 357
DI 10.1002/rob.20287
PG 21
WC Robotics
SC Robotics
GA 421HH
UT WOS:000264349500002
ER
PT J
AU Helmick, D
Angelova, A
Matthies, L
AF Helmick, Daniel
Angelova, Anelia
Matthies, Larry
TI Terrain Adaptive Navigation for Planetary Rovers
SO JOURNAL OF FIELD ROBOTICS
LA English
DT Article
ID OFF-ROAD NAVIGATION; EXPLORATION ROVERS; OBSTACLE DETECTION; CLASSIFIER
FUSION; MOBILE ROBOT; PERFORMANCE; SLIP
AB This paper describes the design, implementation, and experimental results of a navigation system for planetary rovers called Terrain Adaptive Navigation (TANav). This system was designed to enable greater access to and more robust operations within terrains of widely varying slippage. The system achieves this goal by using onboard stereo cameras to remotely classify surrounding terrain, predict the slippage of that terrain, and use this information in the planning of a path to the goal. This navigation system consists of several integrated techniques: goodness map generation, terrain triage, terrain classification, remote slip prediction, path planning, High-Fidelity Traversability Analysis, and slip-compensated path following. Results from experiments with an end-to-end onboard implementation of the TANav system in a Mars analog environment are shown and compared to results from experiments with a more traditional navigation system that does not account for terrain properties. (C) 2009 Wiley Periodicals, Inc.
C1 [Helmick, Daniel] CALTECH, Jet Prop Lab, Mobil & Manipulat Grp, Pasadena, CA 91109 USA.
[Angelova, Anelia] CALTECH, Dept Comp Sci, Pasadena, CA 91125 USA.
[Matthies, Larry] CALTECH, Jet Prop Lab, Comp Vis Grp, Pasadena, CA 91109 USA.
RP Helmick, D (reprint author), CALTECH, Jet Prop Lab, Mobil & Manipulat Grp, 4800 Oak Grove Dr, Pasadena, CA 91109 USA.
EM dmh@jpl.nasa.gov; anelia@vision.caltech.edu; lhm@jpl.nasa.gov
FU NASA
FX The research described in this publication was carried out at the Jet
Propulsion Laboratory, California Institute of Technology, under
contract from the National Aeronautics and Space Administration (NASA),
with funding from the Mars Technology Program, NASA Science Mission
Directorate.
NR 42
TC 31
Z9 32
U1 2
U2 9
PU JOHN WILEY & SONS INC
PI HOBOKEN
PA 111 RIVER ST, HOBOKEN, NJ 07030 USA
SN 1556-4959
J9 J FIELD ROBOT
JI J. Field Robot.
PD APR
PY 2009
VL 26
IS 4
BP 391
EP 410
DI 10.1002/rob.20292
PG 20
WC Robotics
SC Robotics
GA 421HH
UT WOS:000264349500004
ER
PT J
AU DeBonis, JR
AF DeBonis, James R.
TI RANS Analyses of Turbofan Nozzles With Internal Wedge Deflectors for
Noise Reduction
SO JOURNAL OF FLUIDS ENGINEERING-TRANSACTIONS OF THE ASME
LA English
DT Article; Proceedings Paper
CT AIAA 46th Aerospace Sciences Meeting and Exhibit
CY JAN 07-10, 2008
CL Reno, NV
SP Amer Inst Aeronaut & Astronaut
DE computational fluid dynamics; jets; Navier-Stokes equations; noise;
nozzles; turbulence
ID EXHAUST
AB Computational fluid dynamics (CFD) was used to evaluate the flow field and thrust performance of a promising concept for reducing the noise at take-off of dual-stream turbofan nozzles. The concept, offset stream technology, reduces the jet noise observed on the ground by diverting (offsetting) a portion of the fan flow below the core flow, thickening and lengthening this layer between the high-velocity core flow and the ground observers. In this study a wedge placed in the internal fan stream is used as the diverter. Wind, a Reynolds averaged Navier-Stokes (RANS) code, was used to analyze the flow field of the exhaust plume and to calculate nozzle performance. Results showed that the wedge diverts all of the fan flow to the lower side of the nozzle, and the turbulent kinetic energy on the observer side of the nozzle is reduced. This reduction in turbulent kinetic energy should correspond to a reduction in noise. However, because all of the fan flow is diverted, the upper portion of the core flow is exposed to the freestream, and the turbulent kinetic energy on the upper side of the nozzle is increased, creating an unintended noise source. The blockage due to the wedge reduces the fan mass flow proportional to its blockage, and the overall thrust is consequently reduced. The CFD predictions are in very good agreement with experimental flow field data, demonstrating that RANS CFD can accurately predict the velocity and turbulent kinetic energy fields. While this initial design of a large scale wedge nozzle did not meet noise reduction or thrust goals, this study identified areas for improvement and demonstrated that RANS CFD can be used to improve the concept.
C1 NASA, Inlet & Nozzle Branch, Glenn Res Ctr, Cleveland, OH 44135 USA.
RP DeBonis, JR (reprint author), NASA, Inlet & Nozzle Branch, Glenn Res Ctr, Cleveland, OH 44135 USA.
EM james.r.debonis@nasa.gov
NR 18
TC 3
Z9 3
U1 2
U2 3
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 APR
PY 2009
VL 131
IS 4
AR 041104
DI 10.1115/1.3089536
PG 17
WC Engineering, Mechanical
SC Engineering
GA 418EY
UT WOS:000264132100004
ER
PT J
AU Vila, DA
de Goncalves, LGG
Toll, DL
Rozante, JR
AF Vila, Daniel A.
de Goncalves, Luis Gustavo G.
Toll, David L.
Rozante, Jose Roberto
TI Statistical Evaluation of Combined Daily Gauge Observations and Rainfall
Satellite Estimates over Continental South America
SO JOURNAL OF HYDROMETEOROLOGY
LA English
DT Article
ID PRECIPITATION CLIMATOLOGY PROJECT; GLOBAL PRECIPITATION; PASSIVE
MICROWAVE; RESOLUTION; DATASET
AB This paper describes a comprehensive assessment of a new high-resolution, gauge-satellite-based analysis of daily precipitation over continental South America during 2004. This methodology is based on a combination of additive and multiplicative bias correction schemes to get the lowest bias when compared with the observed values ( rain gauges). Intercomparisons and cross-validation tests have been carried out between independent rain gauges and different merging techniques. This validation process was done for the control algorithm [Tropical Rainfall Measuring Mission(TRMM) Multisatellite Precipitation Analysis real-time algorithm] and five different merging schemes: additive bias correction; ratio bias correction; TRMM Multisatellite Precipitation Analysis, research version; and the combined scheme proposed in this paper. These methodologies were tested for different months belonging to different seasons and for different network densities. All compared, merging schemes produce better results than the control algorithm; however, when finer temporal ( daily) and spatial scale ( regional networks) gauge datasets are included in the analysis, the improvement is remarkable. The combined scheme consistently presents the best performance among the five techniques tested in this paper. This is also true when a degraded daily gauge network is used instead of a full dataset. This technique appears to be a suitable tool to produce real-time, high-resolution, gauge-and satellite-based analyses of daily precipitation over land in regional domains.
C1 [Vila, Daniel A.] Univ Maryland, CICS, ESSIC, College Pk, MD 20742 USA.
[de Goncalves, Luis Gustavo G.; Toll, David L.] NASA, Goddard Space Flight Ctr, Hydrol Sci Branch, Greenbelt, MD 20771 USA.
[Rozante, Jose Roberto] Cachoeira Paulista, CPTEC, INPE, Sao Paulo, Brazil.
RP Vila, DA (reprint author), Univ Maryland, CICS, ESSIC, 2207 Comp & Space Bldg, College Pk, MD 20742 USA.
EM dvila@essic.umd.edu
RI Vila, Daniel/G-8379-2012; de Goncalves, Luis Gustavo/G-2522-2012;
OI Vila, Daniel/0000-0002-1015-5650; de Goncalves, Luis
Gustavo/0000-0002-1571-0916
FU NASA [NNX06AG91G]; Oak Ridge Associated Universities (ORAU)
FX This study was supported by NASA's LBA Ecology (Group CD36) Project
under Grant NNX06AG91G and the NASA Postdoctoral Program under the Oak
Ridge Associated Universities (ORAU).
NR 24
TC 58
Z9 61
U1 5
U2 17
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 APR
PY 2009
VL 10
IS 2
BP 533
EP 543
DI 10.1175/2008JHM1048.1
PG 11
WC Meteorology & Atmospheric Sciences
SC Meteorology & Atmospheric Sciences
GA 439PQ
UT WOS:000265639900012
ER
PT J
AU Das, S
Kyriakides, I
Chattopadhyay, A
Papandreou-Suppappola, A
AF Das, S.
Kyriakides, I.
Chattopadhyay, A.
Papandreou-Suppappola, A.
TI Monte Carlo Matching Pursuit Decomposition Method for Damage
Quantification in Composite Structures
SO JOURNAL OF INTELLIGENT MATERIAL SYSTEMS AND STRUCTURES
LA English
DT Article
DE wave propagation; structural health monitoring; fiber-reinforced
composite; matching pursuit decomposition; particle filtering; monte
carlo
ID ROLLING-ELEMENT BEARINGS; FREQUENCY RESONANCE TECHNIQUE; PARTICLE
FILTERS; TRACKING
AB In wave-based approach, the presence of damage is visualized in terms of the changes in the signature of the resultant wave that propagates through the structure. In structural health monitoring, the fundamental goal is to detect, localize, and quantify these damage signatures. The current approach uses matching pursuit decomposition (MPD) to compare signals from healthy and damaged structures. However, the major drawback of the MPD is that, in the decomposition process, it performs an exhaustive search over a large dictionary of elementary functions. Therefore, this method of decomposition is associated with a large computational expense. In this research, the Monte Carlo matching pursuit decomposition (MCMPD) is proposed, that adapts a smaller dictionary to the signal structure, thus avoiding the exhaustive search over the time-frequency plane. The proposed algorithm, sequentially estimates a dictionary that contains only those components that match the waveform structure, uses the matching pursuits for the decomposition of the signal and if necessary, adapts the dictionary to the structure of the residues for further decomposition. Finally, we demonstrate using real life data that the MCMPD retains the ability of the matching pursuit to decompose waveforms and quantify them accurately while reducing computational expense.
C1 [Das, S.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA.
[Kyriakides, I.] Arizona State Univ, Dept Elect Engn, Tempe, AZ 85287 USA.
[Chattopadhyay, A.] Arizona State Univ, Dept Mech & Aerosp Engn, Tempe, AZ 85287 USA.
[Chattopadhyay, A.; Papandreou-Suppappola, A.] Arizona State Univ, Adapt Intelligent Mat & Syst AIMS Ctr, Tempe, AZ 85287 USA.
[Papandreou-Suppappola, A.] Arizona State Univ, Dept Elect Engn, Tempe, AZ 85287 USA.
RP Das, S (reprint author), NASA, Ames Res Ctr, MS 269-1, Moffett Field, CA 94035 USA.
EM Santanu.Das@asu.edu
FU Air Force Office of Scientific Research [F496200310174]
FX This research was supported by the Air Force Office of Scientific
Research, grant number: F496200310174, technical monitor Dr Clark
Allred. The financial support is gratefully acknowledged. The authors
would also like to thank the MURI Program, Air Force Office of
Scientific Research, grant number: FA9550-06-1-0309; Technical Monitor,
Dr Victor Giurgiutiu.
NR 35
TC 14
Z9 14
U1 0
U2 1
PU SAGE PUBLICATIONS LTD
PI LONDON
PA 1 OLIVERS YARD, 55 CITY ROAD, LONDON EC1Y 1SP, ENGLAND
SN 1045-389X
J9 J INTEL MAT SYST STR
JI J. Intell. Mater. Syst. Struct.
PD APR
PY 2009
VL 20
IS 6
BP 647
EP 658
DI 10.1177/1045389X08097386
PG 12
WC Materials Science, Multidisciplinary
SC Materials Science
GA 423TH
UT WOS:000264518100001
ER
PT J
AU Xiang, Z
Thomas, GW
Thornburg, KM
Cabrol, N
Grin, E
Anderson, RC
AF Xiang, Zhen
Thomas, Geb W.
Thornburg, Kristopher M.
Cabrol, Nathalie
Grin, Edmond
Anderson, Robert C.
TI Slope Perception from Monoscopic Field Images: Applications to Mobile
Robot Navigation
SO JOURNAL OF INTELLIGENT & ROBOTIC SYSTEMS
LA English
DT Article
DE Slope perception; Slope estimation; Robotic teleoperation; Slope
perception model; Image perception
ID SLANT UNDERESTIMATION; GEOGRAPHICAL-SLANT; URBAN SEARCH; MODEL
AB When remotely navigating a mobile robot, operators must estimate the slope of local terrain in order to avoid areas that are too steep to climb or that slope so steeply downward that the operator would lose control of the rover. Although many rovers are equipped with sensor systems to aid the operator in this task, it is sometimes necessary to estimate slopes from two-dimensional images, either when planning operations or when the operator wishes to monitor the results of a sensor system. This experiment compares the operator's estimates of the slope in Martian terrain with the actual slope determined from three-dimensional data. The ten participants overestimated the slope of the indicated regions by an average of 19A degrees (SD 16A degrees). An analytic model of the error, based on psychophysical analysis, accurately predicts the average magnitude of the errors. Implementation of this model eliminates an average amount of participant error. However, the large estimate variance within and between participants and images still poses a challenge for accurate slope estimation.
C1 [Xiang, Zhen; Thomas, Geb W.; Thornburg, Kristopher M.] Univ Iowa, Iowa City, IA 52242 USA.
[Cabrol, Nathalie; Grin, Edmond] NASA Ames SETI, Moffett Field, CA USA.
[Anderson, Robert C.] CALTECH, Jet Prop Lab, Pasadena, CA USA.
RP Thornburg, KM (reprint author), Univ Iowa, Iowa City, IA 52242 USA.
EM kthornbu@engineering.uiowa.edu
NR 19
TC 0
Z9 0
U1 1
U2 3
PU SPRINGER
PI DORDRECHT
PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS
SN 0921-0296
J9 J INTELL ROBOT SYST
JI J. Intell. Robot. Syst.
PD APR
PY 2009
VL 54
IS 4
BP 595
EP 612
DI 10.1007/s10846-008-9281-y
PG 18
WC Computer Science, Artificial Intelligence; Robotics
SC Computer Science; Robotics
GA 423GM
UT WOS:000264484800003
ER
PT J
AU Foster, L
Waagen, A
Aijaz, N
Hurley, M
Luis, A
Rinsky, J
Satyavolu, C
Way, MJ
Gazis, P
Srivastava, A
AF Foster, Leslie
Waagen, Alex
Aijaz, Nabeela
Hurley, Michael
Luis, Apolonio
Rinsky, Joel
Satyavolu, Chandrika
Way, Michael J.
Gazis, Paul
Srivastava, Ashok
TI Stable and Efficient Gaussian Process Calculations
SO JOURNAL OF MACHINE LEARNING RESEARCH
LA English
DT Article
DE Gaussian processes; low rank approximations; numerical stability;
photometric redshift; subset of regressors method
ID PROCESS REGRESSION; FACTORIZATION
AB The use of Gaussian processes can be an effective approach to prediction in a supervised learning environment. For large data sets, the standard Gaussian process approach requires solving very large systems of linear equations and approximations are required for the calculations to be practical. We will focus on the subset of regressors approximation technique. We will demonstrate that there can be numerical instabilities in a well known implementation of the technique. We discuss alternate implementations that have better numerical stability properties and can lead to better predictions. Our results will be illustrated by looking at an application involving prediction of galaxy redshift from broadband spectrum data.
C1 [Foster, Leslie; Waagen, Alex; Aijaz, Nabeela; Hurley, Michael; Luis, Apolonio; Rinsky, Joel; Satyavolu, Chandrika] San Jose State Univ, Dept Math, San Jose, CA 95192 USA.
[Way, Michael J.] NASA, Goddard Inst Space Studies, New York, NY 10025 USA.
[Gazis, Paul; Srivastava, Ashok] NASA, Ames Res Ctr, Intelligent Syst Div, Moffett Field, CA 94035 USA.
RP Foster, L (reprint author), San Jose State Univ, Dept Math, San Jose, CA 95192 USA.
EM FOSTER@MATH.SJSU.EDU; AWAAGEN@MAILBOLT.COM; NABBO_A@YAHOO.COM;
MHURLEY@GMAIL.COM; JPOLOROLU@GMAIL.COM; JOEL_RINSKY@YAHOO.COM;
CHANDRIKA_S84@YAHOO.COM; MICHAEL.J.WAY@NASA.GOV;
PGAZIS@MAIL.ARC.NASA.GOV; ASHOK@EMAIL.ARC.NASA.GOV
RI Way, Michael/D-5254-2012;
OI Way, Michael/0000-0003-3728-0475
NR 30
TC 17
Z9 17
U1 0
U2 1
PU MICROTOME PUBL
PI BROOKLINE
PA 31 GIBBS ST, BROOKLINE, MA 02446 USA
SN 1532-4435
J9 J MACH LEARN RES
JI J. Mach. Learn. Res.
PD APR
PY 2009
VL 10
BP 857
EP 882
PG 26
WC Automation & Control Systems; Computer Science, Artificial Intelligence
SC Automation & Control Systems; Computer Science
GA 507BJ
UT WOS:000270824600002
ER
PT J
AU Shi, C
Zhang, Y
Gu, C
Chen, B
Seballos, L
Olson, T
Zhang, JZ
AF Shi, Chao
Zhang, Yi
Gu, Claire
Chen, Bin
Seballos, Leo
Olson, Tammy
Zhang, Jin Z.
TI Molecular Fiber Sensors Based on Surface Enhanced Raman Scattering
(SERS)
SO JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY
LA English
DT Review
DE Surface Enhanced Raman Scattering (SERS); Optical Fiber; Molecular
Detection; Silver Nanoparticles (SNPs)
ID RHODAMINE 6G MOLECULES; CHEMICAL SENSORS; SILVER ELECTRODE;
OPTICAL-FIBERS; METAL-FILMS; SPECTROSCOPY; NANOPARTICLES; RESONANCE;
DYE; BIOSENSORS
AB Molecular sensors based on surface enhanced Raman scattering (SERS) and optical fibers have been widely used in biological, environmental and chemical detection procedures due to their unique advantages, such as molecular specificity, high sensitivity and flexibility In this paper, we review the development and highlight some of the important milestones of SERS fiber sensor development with emphasis on recent work to improve the sensitivity of the fiber sensors. In particular in the area to increase the sensitivity, we've reviewed various methods of sample preparation as well as different fiber SERS sensors. One way is to strengthen the field enhancement around the surface of the probe tip and the other is to increase the number of the interacting particles during the SERS process. These techniques are known as the double substrate "sandwich" structure (DSSS) and the liquid core photonic crystal fiber (LCPCF), and in both cases the sensitivities are significantly improved. These fiber sensors were tested with Rhodamine 6G, human insulin and tryptophan and showed excellent performance.
C1 [Shi, Chao; Zhang, Yi; Gu, Claire] Univ Calif Santa Cruz, Dept Elect Engn, Santa Cruz, CA 95064 USA.
[Chen, Bin] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA.
[Seballos, Leo; Olson, Tammy; Zhang, Jin Z.] Univ Calif Santa Cruz, Dept Chem & Biochem, Santa Cruz, CA 95064 USA.
RP Gu, C (reprint author), Univ Calif Santa Cruz, Dept Elect Engn, Santa Cruz, CA 95064 USA.
FU National Science Foundation [ECS-0401206]; NASA PIDDP; ASTEP; Department
of Defense; UCSC special research grant; University Affiliated Research
Center's Aligned Research Program
FX We acknowledge the financial support from the National Science
Foundation (ECS-0401206), NASA PIDDP and ASTEP partial supports,
Department of Defense, the UCSC special research grant, and the
University Affiliated Research Center's Aligned Research Program.
NR 68
TC 19
Z9 19
U1 5
U2 36
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 APR
PY 2009
VL 9
IS 4
BP 2234
EP 2246
DI 10.1166/jnn.2009.SE41
PG 13
WC Chemistry, Multidisciplinary; Nanoscience & Nanotechnology; Materials
Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter
SC Chemistry; Science & Technology - Other Topics; Materials Science;
Physics
GA 423IK
UT WOS:000264489800006
PM 19437961
ER
PT J
AU Sun, LQ
Cui, RH
Jalbout, AF
Li, MJ
Pan, XM
Wang, RS
Xie, HM
AF Sun, L. Q.
Cui, R. H.
Jalbout, A. F.
Li, M. J.
Pan, X. M.
Wang, R. S.
Xie, H. M.
TI LiFePO4 as an optimum power cell material
SO JOURNAL OF POWER SOURCES
LA English
DT Article; Proceedings Paper
CT 14th International Meeting on Lithium Batteries
CY JUN 22-28, 2008
CL Tianjin, PEOPLES R CHINA
SP Tianjin Inst Power Sources, China Ind Assoc Power Sources, Tianjin Local Govt
DE LiFePO4; Polyacence; Lithium ion batteries; Power cells
ID CARBON-COATED LIFEPO4; CATHODE MATERIALS; ELECTROCHEMICAL PROPERTIES;
LITHIUM BATTERIES; ROUTE; COATINGS; LIXFEPO4; FEPO4; IRON
AB Nano-crystallized LiFePO4 has been synthesized with a simple three-step-synthesis technology in the presence of nano-ferric oxide as iron source and polyacence (PAS) as a reductive agent and high conductive carbon source. The use of PAS increases the conductivity and prevents the particles growth. The most feasible calcined temperature and time was investigated and the best cell performance was delivered by the sample calcined at 700 degrees C for 4 h. This material shows excellent specific capacity and cycle efficiency at high current rates, almost no capacity loss can be observed Lip to 100 cycles which make it more superior as an optimum power cell cathode material. (c) 2008 Elsevier B.V. All rights reserved.
C1 [Sun, L. Q.; Cui, R. H.; Li, M. J.; Pan, X. M.; Wang, R. S.; Xie, H. M.] NE Normal Univ, Fac Chem, Inst Funct Mat, Changchun 130024, Jilin, Peoples R China.
[Jalbout, A. F.] NASA, Astrobiol Inst, Tucson, AZ 85721 USA.
[Jalbout, A. F.] Univ Arizona, Dept Chem, Tucson, AZ 85721 USA.
RP Wang, RS (reprint author), NE Normal Univ, Fac Chem, Inst Funct Mat, Changchun 130024, Jilin, Peoples R China.
EM wangrs@nenu.edu.cn; xiehm136@nenu.edu.cn
NR 23
TC 22
Z9 28
U1 2
U2 6
PU ELSEVIER SCIENCE BV
PI AMSTERDAM
PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
SN 0378-7753
J9 J POWER SOURCES
JI J. Power Sources
PD APR 1
PY 2009
VL 189
IS 1
SI SI
BP 522
EP 526
DI 10.1016/j.jpowsour.2008.10.120
PG 5
WC Chemistry, Physical; Electrochemistry; Energy & Fuels; Materials
Science, Multidisciplinary
SC Chemistry; Electrochemistry; Energy & Fuels; Materials Science
GA 435BG
UT WOS:000265317600086
ER
PT J
AU Wesley, WR
Simpson, JR
Parker, PA
Pignatiello, JJ
AF Wesley, Wayne R.
Simpson, James R.
Parker, Peter A.
Pignatiello, Joseph J., Jr.
TI Exact Calculation of Integrated Prediction Variance for Response Surface
Designs on Cuboidal and Spherical Regions
SO JOURNAL OF QUALITY TECHNOLOGY
LA English
DT Article
DE Design Optimality; IV-Criterion; Region Moments; Restricted
Randomization
ID SECOND-ORDER DESIGNS; SPLIT-PLOT DESIGNS; EQUIVALENT ESTIMATION;
CONSTRUCTION; COMPOSITE; CRITERIA; MODELS
AB Over the years, design optimality evaluation of response surface designs focused mainly on D-optimality and G-optimality criteria. The apparent limited use of the IV-optimality criterion appears to be influenced by the computational challenges associated with the criterion. The lack of available computer code appears to be the main reason for limited use of the IV-optimality criterion. In addition, the IV-optimality criterion appears more difficult to code than the D-optimality criterion because of the integration required over the specified design region. In this paper, an efficient and exact method is presented for computing the IV-optimality criterion for selected response surface designs. The pseudo-code for the computer program is also presented. The investigation examines both spherical and cuboidal regions of interest. In addition, an analytical approach is outlined for computing the IV-optimality criterion for second-order split-plot designs. A particular feature of the analytical expressions is that they are derived using the design parameters. In addition, several comparisons of second-order response surface designs are illustrated for completely randomized designs and split-plot designs.
C1 [Wesley, Wayne R.] Univ Technol, Fac Engn & Comp, Kingston 6, Jamaica.
[Simpson, James R.] 53d Test Management Grp, Eglin AFB, FL USA.
[Parker, Peter A.] NASA, Langley Res Ctr, Hampton, VA 23681 USA.
[Pignatiello, Joseph J., Jr.] Florida State Univ, Dept Ind & Mfg Engn, Tallahassee, FL 32310 USA.
RP Wesley, WR (reprint author), Univ Technol, Fac Engn & Comp, Kingston 6, Jamaica.
EM wwesley3@hotmail.com; James.Simpson@eglin.af.mil;
peter.a.parker@nasa.gov; pigna@eng.fsu.edu
NR 29
TC 1
Z9 1
U1 2
U2 4
PU AMER SOC QUALITY CONTROL-ASQC
PI MILWAUKEE
PA 600 N PLANKINTON AVE, MILWAUKEE, WI 53203 USA
SN 0022-4065
J9 J QUAL TECHNOL
JI J. Qual. Technol.
PD APR
PY 2009
VL 41
IS 2
BP 165
EP 180
PG 16
WC Engineering, Industrial; Operations Research & Management Science;
Statistics & Probability
SC Engineering; Operations Research & Management Science; Mathematics
GA 424VH
UT WOS:000264595900008
ER
PT J
AU Mishchenko, MI
Geogdzhayev, IV
Liu, L
Lacis, AA
Cairns, B
Travis, LD
AF Mishchenko, Michael I.
Geogdzhayev, Igor V.
Liu, Li
Lacis, Andrew A.
Cairns, Brian
Travis, Larry D.
TI Toward unified satellite climatology of aerosol properties: What do
fully compatible MODIS and MISR aerosol pixels tell us?
SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
LA English
DT Article
DE Tropospheric aerosols; Remote sensing
ID OPTICAL DEPTH; RETRIEVALS; AERONET; OCEAN; SPACE; PRODUCTS; FUTURE;
RECORD
AB Because of the global nature of aerosol effects on climate, satellite observations have been and will be an indispensable source of information about aerosol characteristics for use in various assessments of climate and climate change. There have been parallel claims of unprecedented accuracy of aerosol retrievals with the moderate-resolution imaging spectroradiometer (MODIS) and multiangle imaging spectroradiometer (MISR). These claims have been based on limited comparisons with ground-based observations which, however, are not necessarily indicative of the actual global performance of these satellite sensors. Fortunately, both instruments have been flown for many years on the same Terra platform, which provides a unique opportunity to compare fully collocated pixel-level MODIS and MISR aerosol retrievals directly and globally. Our present extensive analysis of similar to 8 years of the MODIS-Terra and MISR aerosol data documents unexpected significant disagreements at the pixel level as well as between long-term and spatially averaged aerosol properties. The only point on which both datasets seem to fully agree is that there may have been a weak increasing tendency in the globally averaged aerosol optical thickness (AOT) over the land and no long-term AOT tendency over the oceans. Overall our new results suggest that the current knowledge of the global distribution of the AOT and, especially, aerosol microphysical characteristics remains unsatisfactory. Published by Elsevier Ltd.
C1 [Mishchenko, Michael I.; Geogdzhayev, Igor V.; Liu, Li; Lacis, Andrew A.; Cairns, Brian; Travis, Larry D.] NASA, Goddard Inst Space Studies, New York, NY 10025 USA.
RP Mishchenko, MI (reprint author), NASA, Goddard Inst Space Studies, 2880 Broadway, New York, NY 10025 USA.
EM mmishchenko@giss.nasa.gov
RI Lacis, Andrew/D-4658-2012; Mishchenko, Michael/D-4426-2012;
OI Cairns, Brian/0000-0002-1980-1022
FU NASA EOS; National Polar-orbiting Operational Environmental Satellite
System's Advanced Technology; Program Executive Office for Environmental
Satellites
FX We thank John Martonchik for valuable advice regarding the MISR aerosol
retrieval algorithm and datasets, Lorraine Remer for her assistance in
the understanding of the MODIS aerosol product, and Ralph Kahn for
valuable discussions. This research was funded by the NASA EOS program
and by the National Polar-orbiting Operational Environmental Satellite
System's Advanced Technology and Plans Program Element of the Program
Executive Office for Environmental Satellites.
NR 24
TC 33
Z9 33
U1 1
U2 6
PU PERGAMON-ELSEVIER SCIENCE LTD
PI OXFORD
PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND
SN 0022-4073
EI 1879-1352
J9 J QUANT SPECTROSC RA
JI J. Quant. Spectrosc. Radiat. Transf.
PD APR-MAY
PY 2009
VL 110
IS 6-7
BP 402
EP 408
DI 10.1016/j.jqsrt.2009.01.007
PG 7
WC Optics; Spectroscopy
SC Optics; Spectroscopy
GA 433VH
UT WOS:000265233400009
ER
PT J
AU Floros, MW
Johnson, W
AF Floros, Matthew W.
Johnson, Wayne
TI Performance Analysis of the Slowed-Rotor Compound Helicopter
Configuration
SO JOURNAL OF THE AMERICAN HELICOPTER SOCIETY
LA English
DT Article
AB The calculated performance of a slowed-rotor compound aircraft, particularly at high flight speeds, is examined. Correlation of calculated and measured performance is presented for a NASA Langley high advance ratio test to establish the capability to model rotors in such flight conditions. The predicted performance of an isolated rotor and a wing and rotor combination are examined in detail. Three tip speeds and a range of collective pitch settings are investigated. A tip speed of 230 ft/s and zero collective pitch are found to be the best condition to minimize rotor drag over a wide speed range. Detailed rotor and wing performance is examined for both sea level and cruise altitude conditions. Rotor and wing power are found to be primarily from profile drag, except at low speed where the wing is near stall. Increased altitude offloads lift from the rotor to the wing, reducing total power required.
C1 [Floros, Matthew W.] USA, Res Lab, Hampton, VA USA.
[Johnson, Wayne] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA.
RP Floros, MW (reprint author), NASA, Langley Res Ctr, MS 266, Hampton, VA 23681 USA.
EM matt.floros@us.army.mil
NR 14
TC 9
Z9 9
U1 1
U2 4
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 APR
PY 2009
VL 54
IS 2
AR 022002
DI 10.4050/JAHS.54.022002
PG 12
WC Engineering, Aerospace
SC Engineering
GA V16MQ
UT WOS:000207874100002
ER
PT J
AU Savas, O
Green, RB
Caradonna, FX
AF Savas, Oemer
Green, Richard B.
Caradonna, Francis X.
TI Coupled Thrust and Vorticity Dynamics during Vortex Ring State
SO JOURNAL OF THE AMERICAN HELICOPTER SOCIETY
LA English
DT Article
AB This paper focuses on the vortex ring state (VRS) that is observed in the flow around a rotor during rapid descent. In VRS, the vortex filaments trailed off the blades coalesce around the rotor disk. This vortex ring detaches into the wake periodically, causing extreme oscillations in thrust, with periods on the order of several tens of rotor revolutions. The phase relation between the thrust cycle and vorticity distribution at the rotor disk is discussed. Maxima of the VRS thrust oscillations correlate well with the maxima of circulation, enstrophy, and minima of enstrophy dispersion radius observed in the vicinity of the rotor disk.
C1 [Savas, Oemer] Univ Calif Berkeley, Dept Mech Engn, Berkeley, CA 94720 USA.
[Green, Richard B.] Univ Glasgow, Dept Aerosp Engn, Glasgow G12 8QQ, Lanark, Scotland.
[Caradonna, Francis X.] NASA Ames Res Ctr, Aeroflightdynam Directorate, Army RDECOM, Moffett Field, CA USA.
RP Savas, O (reprint author), Univ Calif Berkeley, Dept Mech Engn, Berkeley, CA 94720 USA.
EM savas@me.berkeley.edu
NR 26
TC 3
Z9 3
U1 0
U2 1
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 APR
PY 2009
VL 54
IS 2
AR 022001
DI 10.4050/JAHS.54.022001
PG 10
WC Engineering, Aerospace
SC Engineering
GA V16MQ
UT WOS:000207874100001
ER
PT J
AU Grinstead, JH
Wright, MJ
Bogdanoff, DW
Allen, GA
AF Grinstead, Jay H.
Wright, Michael J.
Bogdanoff, David W.
Allen, Gary A.
TI Shock Radiation Measurements for Mars Aerocapture Radiative Heating
Analysis
SO JOURNAL OF THERMOPHYSICS AND HEAT TRANSFER
LA English
DT Article; Proceedings Paper
CT AIAA 46th Aerospace Sciences Meeting and Exhibit
CY JAN 07-10, 2008
CL Reno, NV
SP Amer Inst Aeronaut & Astronaut
ID NONEQUILIBRIUM
AB NASA's In-Space Propulsion Technology program is supporting the development of shock radial. ion transport models for aerocapture missions to Mars and Venus. Phenomenological models of nonequilibrium shock radiation will be incorporated into high-fidelity flowlield computations used to predict the aerothermal environments for a Mars or Venus aerocapture entry vehicle. These models are validated with shock radiance measurements obtained at flight-relevant conditions. A comprehensive test series in the NASA Ames Electric Arc Shock Tube facility at a representative freestream condition was recently completed. The facility's optical instrumentation enabled spectral measurements of shocked gas radiation from the vacuum ultraviolet to the near infrared. The instrumentation captured the nonequilibrium postshock excitation and relaxation dynamics of dispersed spectral features. A description of the shock tube facility, optical instrumentation, and examples of the test data are presented.
C1 [Grinstead, Jay H.; Wright, Michael J.] NASA, Ames Res Ctr, Reacting Flow Environm Branch, Moffett Field, CA 94035 USA.
[Bogdanoff, David W.; Allen, Gary A.] ELORET Corp, Reacting Flow Environm Branch, Moffett Field, CA 94035 USA.
RP Grinstead, JH (reprint author), NASA, Ames Res Ctr, Reacting Flow Environm Branch, MS 230-2, Moffett Field, CA 94035 USA.
NR 21
TC 11
Z9 11
U1 0
U2 1
PU AMER INST AERONAUT ASTRONAUT
PI RESTON
PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA
SN 0887-8722
J9 J THERMOPHYS HEAT TR
JI J. Thermophys. Heat Transf.
PD APR-JUN
PY 2009
VL 23
IS 2
BP 249
EP 255
DI 10.2514/1.37281
PG 7
WC Thermodynamics; Engineering, Mechanical
SC Thermodynamics; Engineering
GA 434JT
UT WOS:000265271700003
ER
PT J
AU Marschall, J
Pejakovic, DA
Fahrenholtz, WG
Hilmas, GE
Zhu, SM
Ridge, J
Fletcher, DG
Asma, CO
Thomel, J
AF Marschall, Jochen
Pejakovic, Dusan A.
Fahrenholtz, William G.
Hilmas, Greg E.
Zhu, Sumin
Ridge, Jerry
Fletcher, Douglas G.
Asma, Cem O.
Thomel, Jan
TI Oxidation of ZrB(2)-SiC Ultrahigh-Temperature Ce