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Related papers: Variability of EGRET Gamma-Ray Sources

200 papers

The identification of celestial gamma-ray sources with astronomical objects or object classes has remained the initial and most fundamental key for understanding their physical nature. The observational characteristic of a gamma-ray emitter…

Astrophysics · Physics 2009-11-11 Olaf Reimer

We present a method to assess the reliability of the identification of EGRET sources with extragalactic radio sources. We verify that EGRET is detecting the blazar class of AGN. However, many published identifications are found to be…

Astrophysics · Physics 2009-10-28 J. R. Mattox , J. Schachter , L. Molnar , R. C. Hartman , A. R. Patnaik

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 revisit the association of unidentified Galactic plane EGRET sources with tracers of recent massive star formation and death. Up-to-date catalogs of OB associations, SNRs, young pulsars, HII regions and young open clusters were used in…

Astrophysics · Physics 2009-10-28 I. -A. Yadigaroglu , Roger W. Romani

Microquasars are promising candidates to emit high-energy gamma-rays. Moreover, statistical studies show that variable EGRET sources at low galactic latitudes could be associated with the inner spiral arms. The variable nature and the…

Astrophysics · Physics 2014-10-13 V. Bosch-Ramon , J. M. Paredes , G. E. Romero , D. F. Torres

Using survey data, we have re-evaluated the correlation of flat spectrum radio sources with EGRET sources in the Northern sky. A likelihood analysis incorporating the radio and X-ray properties and the Gamma-ray source localization is used…

Astrophysics · Physics 2009-11-07 David Sowards-Emmerd , Roger W. Romani , Peter F. Michelson

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 identity of the persistent EGRET sources in the Galactic plane is largely a mystery. For one of these, 3EG J2227+6122, our complete census of X-ray and radio sources in its error circle reveals a remarkable superposition of an…

Astrophysics · Physics 2009-10-31 J. P. Halpern , E. V. Gotthelf , K. M. Leighly , D. J. Helfand

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

Identifying gamma-ray sources in the Galaxy is hampered by their poor localization, source confusion, and the large variety of potential emitters. Neutron stars and their environment offer various ways to power gamma-ray sources: pulsed…

Astrophysics · Physics 2017-08-23 I. A. Grenier

The vast majority of the celestial gamma-ray sources detected so far have not yet been identified with secure counterparts at other wavelenghts. Here we report the preliminary evidence of a probable association between galaxy clusters and…

Astrophysics · Physics 2009-11-07 Sergio Colafrancesco

The all-sky survey in high-energy gamma rays (E$>$30 MeV) carried out by the Energetic Gamma Ray Experiment Telescope (EGRET) aboard the Compton Gamma-Ray Observatory provides a unique opportunity to examine in detail the diffuse gamma-ray…

Astrophysics · Physics 2011-05-05 P. Sreekumar

The EGRET telescope has repeatedly observed 3EG J1835+5918 as a bright and steady source of high-energy gamma-ray radiation which has not yet been indentified. EGRET data from CGRO observation cycle 1 to 7 have been reanalysed above 100 MeV…

Astrophysics · Physics 2009-11-06 O. Reimer , K. T. S. Brazier , A. Carraminana , G. Kanbach , P. L. Nolan , D. J. Thompson

We investigate whether gamma-ray pulsars viewed at a large angle to the neutron star magnetic pole could contribute to the new population of galactic unidentified EGRET sources associated with the Gould Belt. The faint, soft nature of these…

Astrophysics · Physics 2009-10-31 Alice K. Harding , Bing Zhang

We present preliminary results of a campaign undertaken with different radio interferometers to observe a sample of the most variable unidentified EGRET sources. We expect to detect which of the possible counterparts of the gamma-ray…

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

The advent of the next generation of gamma-ray experiments, led by GLAST, AGILE, INTEGRAL and a host of atmospheric \v{C}erenkov telescopes coming on line in the next few years, will enable ground-breaking discoveries relating to the…

Astrophysics · Physics 2007-05-23 Matthew G. Baring

Using a likelihood analysis (updated since McLaughlin & Cordes 2000) and EGRET detections, upper limits and diffuse background measurements, we find a best-fit luminosity law for the gamma-ray pulsar population. We find that roughly 30 of…

Astrophysics · Physics 2007-05-23 M. A. McLaughlin , J. M. Cordes

We apply a likelihood analysis to pulsar detections, pulsar upper limits, and diffuse background measurements from the OSSE and EGRET instruments on the Compton Gamma Ray Observatory to constrain the luminosity law for gamma-ray pulsars and…

Astrophysics · Physics 2009-10-31 M. A. McLaughlin , J. M. Cordes

A remarkable number of pulsar wind nebulae (PWN) are coincident with EGRET gamma-ray sources. X-ray and radio imaging studies of unidentified EGRET sources have resulted in the discovery of at least 6 new pulsar wind nebulae (PWN).…