Institution
Oak Ridge Associated Universities
Education•Oak Ridge, Tennessee, United States•
About: Oak Ridge Associated Universities is a education organization based out in Oak Ridge, Tennessee, United States. It is known for research contribution in the topics: Population & Divertor. The organization has 1144 authors who have published 1684 publications receiving 41243 citations. The organization is also known as: ORAU & Oak Ridge Institute of Nuclear Studies.
Topics: Population, Divertor, Platelet-activating factor, Tokamak, Neutron
Papers published on a yearly basis
Papers
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TL;DR: The Fast Plasma Investigation (FPI) was developed for flight on the Magnetospheric Multiscale (MMS) mission to measure the differential directional flux of magnetospheric electrons and ions with unprecedented time resolution to resolve kinetic-scale plasma dynamics as mentioned in this paper.
Abstract: The Fast Plasma Investigation (FPI) was developed for flight on the Magnetospheric Multiscale (MMS) mission to measure the differential directional flux of magnetospheric electrons and ions with unprecedented time resolution to resolve kinetic-scale plasma dynamics. This increased resolution has been accomplished by placing four dual 180-degree top hat spectrometers for electrons and four dual 180-degree top hat spectrometers for ions around the periphery of each of four MMS spacecraft. Using electrostatic field-of-view deflection, the eight spectrometers for each species together provide 4pi-sr field-of-view with, at worst, 11.25-degree sample spacing. Energy/charge sampling is provided by swept electrostatic energy/charge selection over the range from 10 eV/q to 30000 eV/q. The eight dual spectrometers on each spacecraft are controlled and interrogated by a single block redundant Instrument Data Processing Unit, which in turn interfaces to the observatory’s Instrument Suite Central Instrument Data Processor. This paper describes the design of FPI, its ground and in-flight calibration, its operational concept, and its data products.
1,038 citations
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TL;DR: In this paper, the authors show that AAE values for an Aerosol Robotic Network (AERONET) set of retrievals from Sun-sky measurements describing full aerosol vertical columns are also strongly correlated with aerosol composition or type.
Abstract: . Recent results from diverse air, ground, and laboratory studies using both radiometric and in situ techniques show that the fractions of black carbon, organic matter, and mineral dust in atmospheric aerosols determine the wavelength dependence of absorption (often expressed as Absorption Angstrom Exponent, or AAE). Taken together, these results hold promise of improving information on aerosol composition from remote measurements. The main purpose of this paper is to show that AAE values for an Aerosol Robotic Network (AERONET) set of retrievals from Sun-sky measurements describing full aerosol vertical columns are also strongly correlated with aerosol composition or type. In particular, we find AAE values near 1 (the theoretical value for black carbon) for AERONET-measured aerosol columns dominated by urban-industrial aerosol, larger AAE values for biomass burning aerosols, and the largest AAE values for Sahara dust aerosols. These AERONET results are consistent with results from other, very different, techniques, including solar flux-aerosol optical depth (AOD) analyses and airborne in situ analyses examined in this paper, as well as many other previous results. Ambiguities in aerosol composition or mixtures thereof, resulting from intermediate AAE values, can be reduced via cluster analyses that supplement AAE with other variables, for example Extinction Angstrom Exponent (EAE), which is an indicator of particle size. Together with previous results, these results strengthen prospects for determining aerosol composition from space, for example using the Glory Aerosol Polarimetry Sensor (APS), which seeks to provide retrievals of multiwavelength single-scattering albedo (SSA) and aerosol optical depth (and therefore aerosol absorption optical depth (AAOD) and AAE), as well as shape and other aerosol properties. Multidimensional cluster analyses promise additional information content, for example by using the Ozone Monitoring Instrument (OMI) to add AAOD in the near ultraviolet and CALIPSO aerosol layer heights to reduce height-absorption ambiguity.
547 citations
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TL;DR: Data from Barrow, AK, at 71 degrees N show that rapid, photochemically driven oxidation of boundary-layer Hg0 after polar sunrise creates a rapidly depositing species of oxidized gaseous mercury in the remote Arctic troposphere at concentrations in excess of 900 pg m(-3).
Abstract: Gaseous elemental mercury (Hg0) is a globally distributed air toxin with a long atmospheric residence time. Any process that reduces its atmospheric lifetime increases its potential accumulation in the biosphere. Our data from Barrow, AK, at 71 degrees N show that rapid, photochemically driven oxidation of boundary-layer Hg0 after polar sunrise, probably by reactive halogens, creates a rapidly depositing species of oxidized gaseous mercury in the remote Arctic troposphere at concentrations in excess of 900 pg m(-3). This mercury accumulates in the snowpack during polar spring at an accelerated rate in a form that is bioavailable to bacteria and is released with snowmelt during the summer emergence of the Arctic ecosystem. Evidence suggests that this is a recent phenomenon that may be occurring throughout the earth's polar regions.
546 citations
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TL;DR: An alkyl ether analog of phosphatidylcholine was prepared from choline plasmalogen of fresh beef heart by reducing the alk-1-enyl moiety to anAlkyl group and by hydrolyzing the sn -2 acyl moieties and replacing it with an acetoyl group.
533 citations
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Goddard Space Flight Center1, Stanford University2, Marshall Space Flight Center3, University of Maryland, College Park4, Pennsylvania State University5, California Institute of Technology6, University of Leicester7, University College London8, Los Alamos National Laboratory9, Oak Ridge Associated Universities10, University of Virginia11, University of California, Santa Cruz12
TL;DR: In this paper, the authors report that the bright, nearby GRB 060614 does not fit into either class, while its temporal lag and peak luminosity fall entirely within the short-duration GRB subclass.
Abstract: Gamma-ray bursts (GRBs) are known to come in two duration classes, separated at ~2 s. Long-duration bursts originate from star-forming regions in galaxies, have accompanying supernovae when these are near enough to observe and are probably caused by massive-star collapsars. Recent observations show that short-duration bursts originate in regions within their host galaxies that have lower star-formation rates, consistent with binary neutron star or neutron star–black hole mergers. Moreover, although their hosts are predominantly nearby galaxies, no supernovae have been so far associated with short-duration GRBs. Here we report that the bright, nearby GRB 060614 does not fit into either class. Its ~102-s duration groups it with long-duration GRBs, while its temporal lag and peak luminosity fall entirely within the short-duration GRB subclass. Moreover, very deep optical observations exclude an accompanying supernova, similar to short-duration GRBs. This combination of a long-duration event without an accompanying supernova poses a challenge to both the collapsar and the merging-neutron-star interpretations and opens the door to a new GRB classification scheme that straddles both long- and short-duration bursts.
500 citations
Authors
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Name | H-index | Papers | Citations |
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Sheng Dai | 122 | 985 | 63472 |
C. Richard Boland | 88 | 314 | 30477 |
Charles O. Rock | 87 | 275 | 22236 |
Richard E. Carson | 83 | 587 | 31351 |
Andrew S. Murray | 80 | 455 | 32547 |
Lindy Blackburn | 78 | 242 | 24100 |
Thomas Thundat | 78 | 622 | 22684 |
Karren L. More | 74 | 428 | 28764 |
Gerald A. Tuskan | 73 | 313 | 25192 |
David B. Geohegan | 71 | 345 | 16422 |
Neil Greenberg | 69 | 429 | 22183 |
Eli Dwek | 68 | 268 | 16734 |
T. Sakamoto | 65 | 523 | 17443 |
Michael G. Stabin | 61 | 279 | 13617 |
Brian W. Sheldon | 60 | 285 | 12491 |