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Related papers: Unidentified Gamma-Ray Sources and Microquasars

200 papers

The variability of the high-energy gamma ray sources in the Third EGRET catalog is analyzed by a new method. We re-analyze the EGRET data to calculate a likelihood function for the flux of each source in each observation, both for…

Astrophysics · Physics 2009-11-10 P. L. Nolan , W. F. Tompkins , I. A. Grenier , P. F. Michelson

Microquasars are potential candidates to produce a non-negligible fraction of the observed galactic cosmic rays. The protons accelerated at the jet termination shock interact with the interstellar medium and may produce detectable fluxes of…

Astrophysics · Physics 2009-11-10 V. Bosch-Ramon , F. A. Aharonian , J. M. Paredes

We explore the possible association between the microquasar LSI+61 303 and the EGRET source 2CG 135+01/3EG J0241$+$6103 by studying, with a detailed numerical model, whether this system can produce the emission and the variability detected…

Astrophysics · Physics 2009-11-10 Valenti Bosch-Ramon , Josep M. Paredes

Presently there are several classes of detected gamma-ray extragalatic sources. They are mostly associated to active galactic nuclei (AGN) and (at soft gamma rays) to gamma-ray bursts (GRB), but not only. Active galactic nuclei consist of…

High Energy Astrophysical Phenomena · Physics 2011-09-09 V. Bosch-Ramon

The possible associations between the microquasars LS 5039 and LS I +61 303 and the EGRET sources 3EG J1824-1514 and 3EG J0241+6103 suggest that microquasars could also be sources of high-energy gamma-rays. In this work, we present a…

Astrophysics · Physics 2014-10-13 V. Bosch-Ramon , J. M. Paredes

We describe the properties of the blazars detected by EGRET and summarize the results on the calculations of the evolution and luminosity function of these sources. Of the large number of possible origins of extragalactic diffuse gamma-ray…

Astrophysics · Physics 2009-10-31 R. Mukherjee , J. Chiang

The 3rd EGRET catalogue lists 271 sources and provides an identification for 101 of them. Thus, the unidentified sources are the majority in the gamma-ray sky, as we currently know it. Solving the mystery of the unidentified gamma-ray…

Astrophysics · Physics 2007-05-23 P. A. Caraveo

The discovery of the microquasar LS 5039 well within the 95% conficence contour of the Unidentified EGRET Source (UES) 3EG J1824-1514 was a major step towards the possible association between microquasars (MQs) and UESs. The recent…

Astrophysics · Physics 2007-05-23 M. Ribo , J. A. Combi , I. F. Mirabel

The EGRET catalogue of unidentified X-ray sources has more objects along the galactic disk than at high galactic latitude, where identifications are comparatively easier. On the other hand, the Egret/GRO mission has already identified…

Astrophysics · Physics 2009-10-30 P. A. Caraveo , G. F. Bignami

The vast majority of the high-energy gamma-ray sources discovered by EGRET are still unidentified. Percentages range from 50% at high galactic latitudes, where blazars are responsible for almost all identified sources, to more than 90% near…

Astrophysics · Physics 2009-11-06 P. A. Caraveo

The possible association between the microquasar LS 5039 and the EGRET source 3EG J1824-1514 suggests that microquasars could also be sources of high energy gamma-rays. In this paper, we explore, with a detailed numerical model, if this…

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

Microquasars are X-ray binaries with relativistic jets. The microquasar LS 5039 turned out to be the first high-energy gamma-ray microquasar candidate due to its likely association with the EGRET source 3EG J1824-1514. Further theoretical…

Astrophysics · Physics 2015-06-24 V. Bosch-Ramon , J. M. Paredes , G. E. Romero

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

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

Astrophysics · Physics 2008-11-26 Olaf Reimer , Diego F. Torres

Over half of GeV gamma-ray sources observed by the EGRET experiment have not yet been identified as known astronomical objects. There is an isotropic component of such unidentified sources, whose number is about 60 in the whole sky. Here we…

Astrophysics · Physics 2009-10-31 Tomonori Totani , Tetsu Kitayama

A model to explain variable gamma-ray sources with high-mass microblazars is described. Inverse Compton interactions between the jet of a microquasar and the UV-photon field of the stellar companion can produce high-energy gamma-rays. The…

Astrophysics · Physics 2007-05-23 M. M. Kaufman Bernado , G. E. Romero , I. F. Mirabel

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…

Very high energy gamma-rays probe the long-standing mystery of the origin of cosmic rays. Produced in the interactions of accelerated particles in astrophysical objects, they can be used to image cosmic particle accelerators. A first…

Astrophysics · Physics 2014-10-13 F. A. Aharonian

We present new theoretical estimates of the relative contributions of unresolved blazars and star-forming galaxies to the extragalactic gamma-ray background (EGB) and discuss constraints on the contributions from alternative mechanisms such…

High Energy Astrophysical Phenomena · Physics 2015-05-20 Floyd W. Stecker , Tonia M. Venters

Recently, Dixon et al. have re-analyzed the EGRET data, finding a statistically significant diffuse $\gamma$-ray emission from the galactic halo. We show that this emission can naturally be explained within a previously-proposed model for…

Astrophysics · Physics 2010-11-30 F. De Paolis , G. Ingrosso , Ph. Jetzer , M. Roncadelli