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arXiv · 0809.0734

Cosmic rays from active galactic nuclei

E. G. Berezhko
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Abstract

Cosmic ray (CR) acceleration at the shock created by the expanding cocoons around active galactic nuclei (AGNs) is studied. It is shown that above the energy $10^{18}$ eV the overall energy spectrum of CRs, produced during the AGN evolution and released in the intergalactic space, has the form $N\propto \epsilon^{-\gamma}$, with $\gamma\approx 2.6$, which extends up to $\epsilon_{max}\sim 10^{20}$ eV. It is concluded that cocoons shocks have to be considered as a main source of extragalactic CRs, which together with Galactic supernova remnants provide the observed CR spectrum.

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E. G. Berezhko. 2008-09-04. Cosmic rays from active galactic nuclei. https://doi.org/10.1086/592233

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