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Non-thermal Cosmic Backgrounds and prospects for future high-energy observations of blazars

P. Giommi·S. Colafrancesco
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Abstract

We discuss the contribution of the blazar population to the extragalactic background radiation across the electromagnetic (e.m.) spectrum with particular reference to the microwave, hard-X-ray and gamma-ray bands. Our estimates are based on a recently derived blazar radio LogN-LogS that was built by combining several radio and multi-frequency surveys. We show that blazar emission integrated over cosmic time gives rise to a considerable broad-band non-thermal cosmic background that dominates the extragalactic brightness in the high-energy part of the e.m. spectrum. We also estimate the number of blazars that are expected to be detected by future planned or hypothetical missions operating in the X-ray and gamma-ray energy bands.

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P. Giommi, S. Colafrancesco. 2006-02-10. Non-thermal Cosmic Backgrounds and prospects for future high-energy observations of blazars. https://arxiv.org/abs/astro-ph/0602243

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