Institution
Universities Space Research Association
Nonprofit•Columbia, Maryland, United States•
About: Universities Space Research Association is a nonprofit organization based out in Columbia, Maryland, United States. It is known for research contribution in the topics: Gamma-ray burst & Galaxy. The organization has 1921 authors who have published 5412 publications receiving 255681 citations. The organization is also known as: USRA.
Topics: Gamma-ray burst, Galaxy, Pulsar, Neutron star, Aerosol
Papers published on a yearly basis
Papers
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Max Planck Society1, University of Alabama in Huntsville2, Universities Space Research Association3, Istituto Nazionale di Fisica Nucleare4, University of Trieste5, University College Dublin6, Marshall Space Flight Center7, Jacobs Engineering Group8, Goddard Space Flight Center9, University of Amsterdam10
TL;DR: In this paper, the second catalog of gamma-ray bursts (GRBs) observed with the Fermi Gamma-ray Burst Monitor (GBM) is presented, which extends the first two-year catalog by two more years, resulting in an overall list of 953 triggered GRBs.
Abstract: This is the second of a series of catalogs of gamma-ray bursts (GRBs) observed with the Fermi Gamma-ray Burst Monitor (GBM). It extends the first two-year catalog by two more years, resulting in an overall list of 953 GBM triggered GRBs. The intention of the GBM GRB catalog is to provide information to the community on the most important observables of the GBM detected GRBs. For each GRB the location and main characteristics of the prompt emission, the duration, peak flux and fluence are derived. The latter two quantities are calculated for the 50-300 keV energy band, where the maximum energy release of GRBs in the instrument reference system is observed and also for a broader energy band from 10-1000 keV, exploiting the full energy range of GBMs low-energy detectors. Furthermore, information is given on the settings and modifications of the triggering criteria and exceptional operational conditions during years three and four in the mission. This second catalog is an official product of the Fermi GBM science team, and the data files containing the complete results are available from the High-Energy Astrophysics Science Archive Research Center.
253 citations
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TL;DR: In this paper, a review of single-frequency rain profiling methods for an airborne or spaceborne radar is presented starting from a unified point of view starting from the basic differential equation, which facilitates the comparisons between the methods and also provides a better understanding of the physical and mathematical basis of the methods.
Abstract: This paper briefly reviews several single-frequency rain profiling methods for an airborne or spaceborne radar. The authors describe the different methods from a unified point of view starting from the basic differential equation. This facilitates the comparisons between the methods and also provides a better understanding of the physical and mathematical basis of the methods. The application of several methods to airborne radar data taken during the Convective and Precipitation/Electrification Experiment is shown. Finally, the authors consider a hybrid method that provides a smooth transition between the Hitschfeld-Bordan method, which performs well at low attenuations, and the surface reference method, for which the relative error decreases with increasing path attenuation.
252 citations
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TL;DR: In this article, the authors present an early analysis of the Taurus molecular complex, on line-of-sight-averaged data and without component separation, and derive maps of the dust temperature T, the dust spectral emissivity index β, and the dust optical depth at 250 μm τ250.
Abstract: Planck allows unbiased mapping of Galactic sub-millimetre and millimetre emission from the most diffuse regions to the densest parts of molecular clouds. We present an early analysis of the Taurus molecular complex, on line-of-sight-averaged data and without component separation. The emission spectrum measured by Planck and IRAS can be fitted pixel by pixel using a single modified blackbody. Some systematic residuals are detected at 353 GHz and 143 GHz, with amplitudes around −7% and +13%, respectively, indicating that the measured spectra are likely more complex than a simple modified blackbody. Significant positive residuals are also detected in the molecular regions and in the 217 GHz and 100 GHz bands, mainly caused by the contribution of the J = 2 → 1a ndJ = 1 → 0 12 CO and 13 CO emission lines. We derive maps of the dust temperature T , the dust spectral emissivity index β, and the dust optical depth at 250 μm τ250. The temperature map illustrates the cooling of the dust particles in thermal equilibrium with the incident radiation field, from 16−17 K in the diffuse regions to 13−14 K in the dense parts. The distribution of spectral indices is centred at 1.78, with a standard deviation of 0.08 and a systematic error of 0.07. We detect a significant T − β anti-correlation. The dust optical depth map reveals the spatial distribution of the column density of the molecular complex from the densest molecular regions to the faint diffuse regions. We use near-infrared extinction and H i data at 21-cm to perform a quantitative analysis of the spatial variations of the measured dust optical depth at 250 μm per hydrogen atom τ250/NH. We report an increase of τ250/NH by a factor of about 2 between the atomic phase and the molecular phase, which has a strong impact on the equilibrium temperature of the dust particles.
250 citations
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Goddard Space Flight Center1, University of Maryland, College Park2, University of Massachusetts Boston3, Cooperative Institute for Research in the Atmosphere4, University of Alabama in Huntsville5, Marshall Space Flight Center6, Yale University7, Universities Space Research Association8, United States Forest Service9, University of Puerto Rico at Mayagüez10, University of Puerto Rico, Río Piedras11, Columbia University12, German Aerospace Center13
TL;DR: The Black Marble nighttime lights product suite (VNP46) is available at 500m resolution since January 2012 with data from the VISible Infrared Imaging Radiometer Suite (VIIRS) Day/Night Band (DNB) onboard the Suomi National Polar-orbiting Platform (SNPP) as discussed by the authors, which utilizes all high-quality, cloud-free, atmospheric-, terrain-, vegetation-, snow-, lunar-, and stray light-corrected radiances to estimate daily nighttime lights (NTL) and other intrinsic surface optical properties.
250 citations
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Zoological Society of London1, University of Würzburg2, German Aerospace Center3, University of Twente4, Wageningen University and Research Centre5, University of Dundee6, Higher University of San Andrés7, University of New South Wales8, University of Zurich9, United Nations Environment Programme10, European Academy of Bozen11, Universities Space Research Association12, Murray State University13, Azim Premji University14, Goddard Space Flight Center15, University of Maryland, College Park16, European Space Agency17, Stellenbosch University18, Carnegie Institution for Science19, University of Ottawa20, African Institute of Science and Technology21, Pennsylvania State University22, Helmholtz Centre for Environmental Research - UFZ23, Edmund Mach Foundation24, Australian Museum25, Office of Environment and Heritage26, Spanish National Research Council27, Council for Scientific and Industrial Research28, University of Granada29, Monash University, Clayton campus30, NASA Headquarters31, Minnesota Department of Natural Resources32, Museum für Naturkunde33, Finnish Environment Institute34, Stockholm Resilience Centre35
TL;DR: This contribution aims to advance the development of a global biodiversity monitoring strategy by updating the previously published definition of EBV, providing a definition of satellite remote sensing EBVs and introducing a set of principles that are believed to be necessary if ecologists and space agencies are to agree on a list of EBVs that can be routinely monitored from space.
Abstract: Although satellite-based variables have for long been expected to be key components to a unified and global biodiversity monitoring strategy, a definitive and agreed list of these variables still remains elusive. The growth of interest in biodiversity variables observable from space has been partly underpinned by the development of the essential biodiversity variable (EBV) framework by the Group on Earth Observations – Biodiversity Observation Network, which itself was guided by the process of identifying essential climate variables. This contribution aims to advance the development of a global biodiversity monitoring strategy by updating the previously published definition of EBV, providing a definition of satellite remote sensing (SRS) EBVs and introducing a set of principles that are believed to be necessary if ecologists and space agencies are to agree on a list of EBVs that can be routinely monitored from space. Progress toward the identification of SRS-EBVs will require a clear understanding of what makes a biodiversity variable essential, as well as agreement on who the users of the SRS-EBVs are. Technological and algorithmic developments are rapidly expanding the set of opportunities for SRS in monitoring biodiversity, and so the list of SRS-EBVs is likely to evolve over time. This means that a clear and common platform for data providers, ecologists, environmental managers, policy makers and remote sensing experts to interact and share ideas needs to be identified to support long-term coordinated actions.
249 citations
Authors
Showing all 1930 results
Name | H-index | Papers | Citations |
---|---|---|---|
Alexander S. Szalay | 166 | 936 | 145745 |
Naomi J. Halas | 140 | 435 | 82040 |
Krzysztof M. Gorski | 132 | 380 | 105912 |
William T. Reach | 131 | 535 | 90496 |
David C. Koo | 119 | 568 | 49040 |
Ranga B. Myneni | 114 | 393 | 53054 |
Chryssa Kouveliotou | 109 | 671 | 47748 |
Darren L. DePoy | 99 | 554 | 38932 |
Mario Hamuy | 95 | 389 | 30391 |
A. A. Moiseev | 95 | 263 | 36948 |
Holland C. Ford | 93 | 347 | 29661 |
Alistair R. Walker | 93 | 580 | 35142 |
Jonathan F. Ormes | 89 | 306 | 27022 |
Andreas Quirrenbach | 89 | 678 | 33504 |
Tyson Littenberg | 89 | 297 | 61373 |