EGRET gamma-ray blazars: luminosity function and contribution to the extragalactic gamma-ray background
نویسندگان
چکیده
منابع مشابه
EGRET Gamma-Ray Blazars: Luminosity Function and Contribution to the Extragalactic Gamma-Ray Background
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 γ-ray emission, it has been postulated that active galaxies might be one of the most likely candidates. However, some of our recent analysis indicate that only 25% of ...
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The large majority of EGRET point sources remain to this day without an identified low-energy counterpart. Whatever the nature of the EGRET unidentified sources, faint unresolved objects of the same class must have a contribution to the diffuse gamma-ray background: if most unidentified objects are extragalactic, faint unresolved sources of the same class contribute to the background, as a dist...
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The COMPTEL and EGRET detectors aboard the Compton Gamma-Ray Observatory measured an extragalactic γ-ray background (EGRB) extending from ∼ 1 MeV to ∼ 100 GeV. Calculations performed making reasonable assumptions indicate that blazars can account for the background between ∼ 10 MeV and ∼ 10 GeV. Below 30 MeV, the background flux and spectrum are not very well determined and a dedicated satellit...
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Very high energy gamma-rays (Eγ > 20 GeV) from blazars traversing cosmological distances through the metagalactic radiation field can convert to electron-positron pairs in photonphoton collisions. The converted gamma rays initiate electromagnetic cascades driven by inverseCompton scattering off the microwave background photons. The cascades shift the injected gamma ray spectrum to MeV-GeV energ...
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ژورنال
عنوان ژورنال: Astroparticle Physics
سال: 1999
ISSN: 0927-6505
DOI: 10.1016/s0927-6505(99)00052-3