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arXiv · 1103.3484

Extragalactic Very-High-Energy gamma-ray background

A. Neronov·D. V. Semikoz
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Abstract

We study the origin of the extragalactic diffuse gamma-ray background using the data from the Fermi telescope. To estimate the background level, we count photons at high Galactic latitudes |b|>60 degrees. Subtracting photons associated to known sources and the residual cosmic ray and Galactic diffuse backgrounds, we estimate the Extragalactic Gamma-ray Background (EGB) flux. We find that the spectrum of EGB in the very-high-energy (VHE) band above 30 GeV follows the stacked spectrum of BL Lacs. LAT data reveal the positive (1+z)^k, 1 30 GeV could be completely explained by emission from unresolved BL Lacs if k~3.

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A. Neronov, D. V. Semikoz. 2011-03-17. Extragalactic Very-High-Energy gamma-ray background. https://doi.org/10.1088/0004-637x%2F757%2F1%2F61

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