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Angular Anisotropies in the Cosmic Gamma-ray Background as a Probe of its Origin

Francesco Miniati·Savvas M. Koushiappas·Tiziana Di Matteo
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Abstract

Notwithstanding the advent of the Gamma-ray Large Area Telescope, theoretical models predict that a significant fraction of the cosmic gamma-ray background (CGB), at the level of 20% of the currently measured value, will remain unresolved. The angular power spectrum of intensity fluctuations of the CGB contains information on its origin. We show that probing the latter from a few tens of arcmin to several degree scales, together with complementary GLAST observations of gamma-ray emission from galaxy clusters and the blazars luminosity function, can discriminate between a background that originates from unresolved blazars or cosmic rays accelerated at structure formation shocks.

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Francesco Miniati, Savvas M. Koushiappas, Tiziana Di Matteo. 2007-08-12. Angular Anisotropies in the Cosmic Gamma-ray Background as a Probe of its Origin. https://doi.org/10.1086/522085

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