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Related papers: Unidentified EGRET Sources

200 papers

The 3rd EGRET Catalog of High-energy Gamma-ray Sources contains 170 unidentified sources, and there is great interest in the nature of these sources. One means of determining source class is the study of flux variability on time scales of…

A large fraction of the detections to be made by the Gamma-ray Large Area Space Telescope (GLAST) will initially be unidentified. We argue that traditional methodological approaches to identify individuals and/or populations of $\gamma$-ray…

Astrophysics · Physics 2009-11-13 Diego F. Torres , Olaf Reimer

H.E.S.S. results from the first three years of nominal operation are presented. Among the many exciting measurements that have been made, most gamma-ray sources are of Galactic origin. I will concentrate here on an overview of Galactic…

Astrophysics · Physics 2016-11-09 D. Berge

The global contribution of unresolved gamma-ray point sources to the extragalactic gamma-ray background has been recently measured down to gamma-ray fluxes lower than those reached with standard source detection techniques, and by employing…

High Energy Astrophysical Phenomena · Physics 2020-05-27 Silvia Manconi , Michael Korsmeier , Fiorenza Donato , Nicolao Fornengo , Marco Regis , Hannes Zechlin

As the highest-energy photons, gamma rays have an inherent interest to astrophysicists and particle physicists studying high-energy, nonthermal processes. Gamma-ray telescopes complement those at other wavelengths, especially radio,…

Astrophysics · Physics 2009-11-10 David J. Thompson

Population studies of unidentified EGRET sources suggest that there exist at least three different populations of galactic gamma-ray sources. One of these populations is formed by young objects distributed along the galactic plane with a…

Astrophysics · Physics 2009-11-10 V. Bosch-Ramon , G. E. Romero , J. M. Paredes

Among unidentified gamma-ray sources in the galactic plane, there are some that present significant variability and have been proposed to be high-mass microquasars. To deepen the study of the possible association between variable low…

Astrophysics · Physics 2009-11-11 V. Bosch-Ramon , J. M. Paredes , G. E. Romero , D. F. Torres

In a novel approach in observational high-energy gamma-ray astronomy, observations carried out by imaging atmospheric Cherenkov telescopes provide necessary templates to pinpoint the nature of intriguing, yet unidentified EGRET gamma-ray…

Astrophysics · Physics 2008-11-26 Olaf Reimer , Stefan Funk

We suggest that ultraluminous X-ray sources (ULXs) and some of the variable low latitude EGRET gamma-ray sources may be two different manifestations of the same underlying phenomena: high-mass microquasars with relativistic jets forming a…

Astrophysics · Physics 2007-05-23 Yousaf M. Butt , Gustavo E. Romero , Diego F. Torres

We will present a summary of the observations of blazars by the Energetic Gamma Ray Experiment Telescope (EGRET) on the Compton Gamma Ray Observatory (CGRO). EGRET has detected high energy gamma-ray emission at energies greater than 100 MeV…

Astrophysics · Physics 2016-01-27 R. Mukherjee

We present a study of 40 low-latitude unidentified 3EG gamma-ray sources which were found to be not positionally coincident with any known class of potential gamma-ray emitters in the Galaxy (Romero, Benaglia & Torres, 1999). We have…

The EGRET telescope on the Compton Gamma-Ray Observatory detected over 200 sources and the majority of these are still unidentified. At least three subpopulations of EGRET sources have been associated with the Galaxy: bright sources lying…

Astrophysics · Physics 2009-11-10 A. K. Harding , P. L. Gonthier , I. A. Grenier , C. A. Perrot

The EGRET instrument on the Compton Gamma Ray Observatory (1991-2000) has positively detected high energy gamma-ray emission from more than 67 active galaxies of the blazar class. The majority of the EGRET blazars are flat-spectrum radio…

Astrophysics · Physics 2009-11-06 R. Mukherjee

When it comes to identifying or to characterizing gamma-ray sources, X-ray observations are of paramount importance. Correlated X-and-gamma-ray flux variations are a powerful identification tool, if the gamma-ray source is unidentified, or…

High Energy Astrophysical Phenomena · Physics 2009-12-25 Patrizia A. Caraveo

The EGRET source 3EG J1835+5918 is the brightest and most accurately positioned of the as-yet unidentified high-energy gamma-ray sources at high Galactic latitude (l,b=89,25). We present a multiwavelength study of the region around it,…

Astrophysics · Physics 2009-10-31 N. Mirabal , J. P. Halpern , M. Eracleous , R. H. Becker

Pulsars discovered since the end of the EGRET mission coincident with unidentified high-energy gamma-ray sources are prime targets for AGILE. Both general surveys and targeted observations have been successful in finding energetic young…

Astrophysics · Physics 2007-05-23 Mallory S. E. Roberts

We summarize basic observational properties of gamma-ray bursts (GRBs), including prompt emission properties, afterglow properties, and classification schemes. We also briefly comment on the current physical understanding of these…

High Energy Astrophysical Phenomena · Physics 2016-12-07 Bing Zhang , Hou-Jun Lü , En-Wei Liang

Nearly one-third of the gamma-ray sources detected by Fermi are still unidentified, despite significant recent progress in this effort. On the other hand, all the gamma-ray extragalactic sources associated in the second Fermi-LAT catalog…

High Energy Astrophysical Phenomena · Physics 2019-08-19 F. Massaro , R. D'Abrusco , A. Paggi , N. Masetti , M. Giroletti , G. Tosti , Howard A. Smith , S. Funk

The limited angular resolution of gamma-ray telescopes prevents the straight identification of the majority of the sources detected so far. While the only certified galactic gamma-ray emitters are associated with pulsars, more than 90% of…

Origin of extragalactic gamma-ray background (EGRB) is still a matter of debate. EGRB can either have truly diffuse or unresolved discrete point sources origin. Majority of the Fermi and EGRET detected identified sources are blazar. So,…

High Energy Astrophysical Phenomena · Physics 2011-12-06 Debbijoy Bhattacharya , M. Errando , R. Mukherjee , M. Boettcher , P. Sreekumar , R. Misra , P. Coppi