Ultrahigh energy cosmic rays as heavy nuclei from cluster accretion shocks
Abstract
Large-scale accretion shocks around massive clusters of galaxies, generically expected in the cold dark matter scenario of cosmological structure formation, are shown to be plausible sources of the observed ultrahigh energy cosmic rays (UHECRs) by accelerating a mixture of heavy nuclei including the iron group elements. Current observations can be explained if the source composition at injection for the heavier nuclei is somewhat enhanced from simple expectations for the accreting gas. The proposed picture should be clearly testable by current and upcoming facilities in the near future through characteristic features in the UHECR spectrum, composition and anisotropy, in particular the rapid increase of the average mass composition with energy from to eV.
Keywords
Cite
@article{arxiv.astro-ph/0701167,
title = {Ultrahigh energy cosmic rays as heavy nuclei from cluster accretion shocks},
author = {Susumu Inoue and Guenter Sigl and Francesco Miniati and Eric Armengaud},
journal= {arXiv preprint arXiv:astro-ph/0701167},
year = {2008}
}
Comments
revised version for PRD; 5 pages, 4 figures