Cosmic rays from active galactic nuclei

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 infinity epsilon(-gamma), with gamma approximate to 2.6, which extends up to epsilon(max) similar to 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.