The Gamma-Ray Background from Blazars: A New Look
نویسنده
چکیده
We present the results of a new model calculation of the γ-ray background produced by unresolved blazars, using the second EGRET catalogue and taking account of flaring. These results are compared to the preliminary γ-ray background spectrum reported recently by the EGRET team. We find that blazars can account for the entire extragalactic γ-ray background observed by EGRET. In addition the EGRET spectrum shows some evidence of a signature for the blazar background, a concavity in the spectrum first pointed out in our earlier paper. Subject headings: galaxies: active – gamma-rays: theory – quasars: general
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