1103.3484 (A. Neronov et al.)

Extragalactic Very-High-Energy gamma-ray background    [PDF]

A. Neronov, D. V. Semikoz

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, 130 GeV could be completely explained by emission from unresolved BL Lacs if k~3.

View original: http://arxiv.org/abs/1103.3484