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
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Lawrence Livermore National Laboratory1, Stanford University2, University of California, Berkeley3, University of Arizona4, University of California, San Diego5, Ames Research Center6, University of Victoria7, Herzberg Institute of Astrophysics8, Space Telescope Science Institute9, Arizona State University10, Université de Montréal11, Los Alamos National Laboratory12, University of California, Los Angeles13, University of Western Ontario14, Subaru15, University of Hertfordshire16, Princeton University17, University of Toronto18, Centre national de la recherche scientifique19, University of Chicago20, University of California, Santa Cruz21, Durham University22, University of Exeter23, University of Georgia24, Stony Brook University25, University of California, Santa Barbara26, American Museum of Natural History27, University of Chile28, Universities Space Research Association29, Cornell University30, University of Toledo31, California Institute of Technology32
TL;DR: In this paper, the Gemini Planet Imager was used to detect a planet orbiting the star 51 Eridani at a projected separation of 13 astronomical units, with a spectrum with strong methane and water vapor absorption.
Abstract: Directly detecting thermal emission from young extrasolar planets allows measurement of their atmospheric composition and luminosity, which is influenced by their formation mechanism. Using the Gemini Planet Imager, we discovered a planet orbiting the \$sim$20 Myr-old star 51 Eridani at a projected separation of 13 astronomical units. Near-infrared observations show a spectrum with strong methane and water vapor absorption. Modeling of the spectra and photometry yields a luminosity of L/LS=1.6-4.0 x 10-6 and an effective temperature of 600-750 K. For this age and luminosity, "hot-start" formation models indicate a mass twice that of Jupiter. This planet also has a sufficiently low luminosity to be consistent with the "cold- start" core accretion process that may have formed Jupiter.
375 citations
University of Leicester1, Goddard Space Flight Center2, University of Maryland, College Park3, Pennsylvania State University4, University College London5, Los Alamos National Laboratory6, California Institute of Technology7, Tel Aviv University8, University of Maryland, Baltimore County9, INAF10, University of Warwick11, Agenzia Spaziale Italiana12, Istanbul University13, Southern Utah University14, Clemson University15, National Science Foundation16, Universities Space Research Association17, University of Copenhagen18, Stockholm University19, Aoyama Gakuin University20
TL;DR: In this paper, ultraviolet and x-ray observations from the Nuclear Spectroscopic Telescope Array (NSTA) of the binary neutron star merger GW170817 were used to detect a high mass (≈0.03 solar masses) wind-driven outflow with moderate electron fraction.
Abstract: With the first direct detection of merging black holes in 2015, the era of gravitational wave (GW) astrophysics began. A complete picture of compact object mergers, however, requires the detection of an electromagnetic (EM) counterpart. We report ultraviolet (UV) and x-ray observations by Swift and the Nuclear Spectroscopic Telescope Array of the EM counterpart of the binary neutron star merger GW170817. The bright, rapidly fading UV emission indicates a high mass (≈0.03 solar masses) wind-driven outflow with moderate electron fraction (Ye ≈ 0.27). Combined with the x-ray limits, we favor an observer viewing angle of ≈30° away from the orbital rotation axis, which avoids both obscuration from the heaviest elements in the orbital plane and a direct view of any ultrarelativistic, highly collimated ejecta (a γ-ray burst afterglow).
373 citations
Max Planck Society1, University of Alabama in Huntsville2, University of Edinburgh3, Istituto Nazionale di Fisica Nucleare4, University of Trieste5, University College Dublin6, Universities Space Research Association7, Marshall Space Flight Center8, Jacobs Engineering Group9, Goddard Space Flight Center10, University of Amsterdam11
TL;DR: In this article, the authors presented the updated set of spectral analyses of gamma-ray bursts (GRBs) detected by the Fermi Gamma-Ray Burst Monitor during its first four years of operation.
Abstract: In this catalog we present the updated set of spectral analyses of gamma-ray bursts (GRBs) detected by the Fermi Gamma-Ray Burst Monitor during its first four years of operation. It contains two types of spectra, time-integrated spectral fits and spectral fits at the brightest time bin, from 943 triggered GRBs. Four different spectral models were fitted to the data, resulting in a compendium of more than 7500 spectra. The analysis was performed similarly but not identically to Goldstein et al. All 487 GRBs from the first two years have been re-fitted using the same methodology as that of the 456 GRBs in years three and four. We describe, in detail, our procedure and criteria for the analysis and present the results in the form of parameter distributions both for the observer-frame and rest-frame quantities. The data files containing the complete results are available from the High-Energy Astrophysics Science Archive Research Center.
369 citations
University of Queensland1, Hebrew University of Jerusalem2, Leibniz Association3, University of Potsdam4, Sun Yat-sen University5, Spanish National Research Council6, Complutense University of Madrid7, University of Exeter8, Universities Space Research Association9, Wuhan University10, University of Haifa11, Marshall Space Flight Center12, Cooperative Institute for Research in the Atmosphere13, University of Maryland, College Park14, Goddard Space Flight Center15, Colorado School of Mines16, National Oceanic and Atmospheric Administration17
TL;DR: In this article, the authors outline the historical development of night-time optical sensors up to the current state-of-the-art sensors, highlight various applications of night light data, discuss the special challenges associated with remote sensing of night lights with a focus on the limitations of current sensors, and provide an outlook for the future of remote sensing.
369 citations
TL;DR: In this article, the authors presented an overview of the polarized sky as seen by Planck HFI at 353 GHz, which is the most sensitive Planck channel for dust polarization.
Abstract: This paper presents an overview of the polarized sky as seen by Planck HFI at 353 GHz, which is the most sensitive Planck channel for dust polarization. We construct and analyse maps of dust polarization fraction and polarization angle at 1° resolution, taking into account noise bias and possible systematic effects. The sensitivity of the Planck HFI polarization measurements allows for the first time a mapping of Galactic dust polarized emission on large scales, including low column density regions. We find that the maximum observed dust polarization fraction is high (pmax = 19.8%), in particular in some regions of moderate hydrogen column density (NH < 2 × 1021 cm-2). The polarization fraction displays a large scatter at NH below a few 1021 cm-2. There is a general decrease in the dust polarization fraction with increasing column density above NH ≃ 1 × 1021 cm-2 and in particular a sharp drop above NH ≃ 1.5 × 1022 cm-2. We characterize the spatial structure of the polarization angle using the angle dispersion function. We find that the polarization angle is ordered over extended areas of several square degrees, separated by filamentary structures of high angle dispersion function. These appear as interfaces where the sky projection of the magnetic field changes abruptly without variations in the column density. The polarization fraction is found to be anti-correlated with the dispersion of polarization angles. These results suggest that, at the resolution of 1°, depolarization is due mainly to fluctuations in the magnetic field orientation along the line of sight, rather than to the loss of grain alignment in shielded regions. We also compare the polarization of thermal dust emission with that of synchrotron measured with Planck, low-frequency radio data, and Faraday rotation measurements toward extragalactic sources. These components bear resemblance along the Galactic plane and in some regions such as the Fan and North Polar Spur regions. The poor match observed in other regions shows, however, that dust, cosmic-ray electrons, and thermal electrons generally sample different parts of the line of sight.
368 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 |