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Related papers: V404 Cygni with Fermi-LAT

200 papers

We perform a blind search for the variability of the gamma-ray sky in the energy range E>1 GeV using 308 weeks of the Fermi-LAT data. We use the technique based on the comparison of the weekly photon counts and exposures in sky pixels by…

High Energy Astrophysical Phenomena · Physics 2015-12-22 M. S. Pshirkov , G. I. Rubtsov

We use joint observations by the Neil Gehrels Swift X-ray Telescope (XRT) and the Fermi Large Area Telescope (LAT) of gamma-ray burst (GRB) afterglows to investigate the nature of the long-lived high-energy emission observed by Fermi LAT.…

High Energy Astrophysical Phenomena · Physics 2018-08-08 The Fermi LAT Collaboration

The Fermi source 4FGL J1848.7-0129 has been historically related to the globular cluster GLIMPSE-C01 since its very first detection. Although this association is widely accepted, as it appears in the most recent Fermi catalog, it deserves…

High Energy Astrophysical Phenomena · Physics 2022-12-07 Pedro L. Luque-Escamilla , Josep Martí , Enrique Mestre , Jorge A. Combi , Juan F. Albacete-Colombo

One of the most intriguing and challenging quests of current astrophysics is to understand the physical conditions and processes responsible for production of high-energy particles, and emission of \gamma-rays. A combination of…

High Energy Astrophysical Phenomena · Physics 2016-06-22 B. Rani , T. P. Krichbaum , J. A. Hodgson , J. A. Zensus

The Fermi Large Area Telescope (LAT) is the most sensitive instrument ever deployed in space for observing gamma-ray emission >100 MeV. This sensitivity has enabled the LAT to detect gamma-ray emission from the Sun during quiescent periods…

High Energy Astrophysical Phenomena · Physics 2013-04-04 N. Omodei , V. Petrosian , M. Pesce-Rollins , the Fermi-LAT Collaboration

The Fermi Gamma-ray Space Telescope was launched more than 13 years ago and since then it has dramatically changed our knowledge of the gamma-ray sky. With more than three billions photons from the whole sky, collected in the energy range…

High Energy Astrophysical Phenomena · Physics 2022-09-09 Giacomo Principe

We report the detection of the lunar gamma-ray emission during the first year of Fermi-LAT observations. Such emission is produced by cosmic ray nuclei interacting with the lunar surface. Thanks to the solar minimum conditions and the…

High Energy Astrophysical Phenomena · Physics 2019-08-15 N. Giglietto

We examine the constraints on the luminosity-dependent density evolution model for the evolution of blazars given the observed spectrum of the diffuse gamma-ray background (DGRB), blazar source-count distribution, and the blazar spectral…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Kevork N. Abazajian , Steve Blanchet , J. Patrick Harding

The Fermi observatory is advancing our knowledge of Gamma-Ray Bursts (GRBs) through pioneering observations at high energies, covering more than 7 decades in energy with the two on-board detectors, the Large Area Telescope (LAT) and the…

High Energy Astrophysical Phenomena · Physics 2010-07-21 Fermi-LAT , Fermi-GBM Collaborations

The Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope discovered a rapid (about 5 days duration), high-energy (E >100 MeV) gamma-ray outburst from a source identified with the blazar PKS 1502+106 (OR 103, S3 1502+10,…

High Energy Astrophysical Phenomena · Physics 2012-08-27 The Fermi LAT Collaboration , the Multifrequency Campaing Collaboration

We report the Fermi Large Area Telescope (LAT) detection of two very-high-energy (VHE, E>100 GeV) gamma-ray photons from the directional vicinity of the distant (redshift, z = 1.1) blazar PKS 0426-380. The null hypothesis that both the 134…

High Energy Astrophysical Phenomena · Physics 2015-06-16 Y. T. Tanaka , C. C. Cheung , Y. Inoue , L. Stawarz , M. Ajello , C. D. Dermer , D. L. Wood , A. Chekhtman , Y. Fukazawa , T. Mizuno , M. Ohno , D. Paneque , D. J. Thompson

Gamma rays from extragalactic sources are attenuated by pair-production interactions with diffuse photons of the extragalactic background light (EBL). Gamma-ray bursts (GRBs) are a source of high-redshift photons above 10 GeV, and could be…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Rudy C. Gilmore , Francisco Prada , Joel R. Primack

Very high-energy (VHE; E > 100 GeV) gamma-rays have been detected from a wide range of astronomical objects, such as SNRs, pulsars and pulsar wind nebulae, AGN, gamma-ray binaries, molecular clouds, and possibly star-forming regions as…

High Energy Astrophysical Phenomena · Physics 2010-01-19 P. H. Thomas Tam , Stefan Wagner , Omar Tibolla , Ryan Chaves

In this letter I report the Fermi Large Area Telescope (LAT) detection of Very High Energy (VHE; E>100 GeV) gamma-ray emission from the BL Lac object RBS 0970. 5.3 years of LAT observations revealed the presence of 3 VHE photon events…

High Energy Astrophysical Phenomena · Physics 2015-06-19 Anthony M. Brown

We present broadband (radio, optical, X-ray and GeV) fits to the afterglow light curves and spectra of three long-duration gamma-ray bursts (GRBs 080916C, 090902B, and 090926A) detected by the Gamma-Ray Burst Monitor (GBM) and Large Area…

High Energy Astrophysical Phenomena · Physics 2015-05-20 S. Y. Feng , Z. G. Dai

The Fermi Large Area Telescope (LAT) has detected thousands of sources since its launch in 2008, with many remaining unidentified. Some of these point sources may arise from source confusion. Specifically, there could be extended sources…

High Energy Astrophysical Phenomena · Physics 2025-04-07 Giovanni Cozzolongo , Alison M. W. Mitchell , Samuel T. Spencer , Dmitry Malyshev , Tim Unbehaun

We report the results of a cross-match study between the hard X-ray and GeV gamma-ray catalogs, by making use of the latest 105-month Swift-BAT and 10-yr Fermi-LAT catalogs, respectively. The spatial cross-matching between the two catalogs…

High Energy Astrophysical Phenomena · Physics 2021-07-26 Naomi Tsuji , Hiroki Yoneda , Yoshiyuki Inoue , Tsuguo Aramaki , Georgia Karagiorgi , Reshmi Mukherjee , Hirokazu Odaka

We present preliminary results of our analysis of the {\it Fermi}-LAT data from the direction of NGC 4151. We find a new gamma-ray source with a statistical significance sigma > 5, shifted by 0.5degr from the position of NGC 4151.…

High Energy Astrophysical Phenomena · Physics 2015-03-06 Rafal Wojaczynski , Andrzej Niedzwiecki , Fu-Guo Xie

We present simultaneous X-ray and radio observations of the black hole X-ray binary V404 Cygni at the end of its 2015 outburst. From 2015 July 11-August 5 we monitored V404 Cygni with Chandra, Swift, and NuSTAR in the X-ray, and with the…

At least a fraction of Gravitational Wave (GW) progenitors are expected to emit an electromagnetic (EM) signal in the form of a short gamma-ray burst (sGRB). Discovering such a transient EM counterpart is challenging because the…

High Energy Astrophysical Phenomena · Physics 2017-06-06 Giacomo Vianello , Nicola Omodei , James Chiang , Seth Digel