Clusters of Galaxies as Storage Room for Cosmic Rays

摘要

It is demonstrated that clusters of galaxies are able to keep cosmic rays for a time exceeding the age of the universe. This phenomenon reveals itself by the production of the diffuse flux of high- energy gamma and neutrino radiation due to the interaction of the cosmic rays with the intracluster gas. The produced flux is determined by the cosmological density of baryons, if a large part of this density is provided by the intracluster gas. The signal from relic cosmic rays has to be compared with the flux produced by the late sources, which can be considered as a background in the search for cosmic-ray production in the past.