Ultrahigh energy cosmic rays as heavy nuclei from cluster accretion shocks

Abstract

Large-scale accretion shocks around massive clusters of galaxies, generically expected in hierarchical scenarios of cosmological structure formation, are shown to be potential 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 testable by current and upcoming facilities in the near future through characteristic features in the UHECR spectrum, composition and anisotropy. The associated X-ray and gamma-ray signatures are also briefly discussed.

arXiv comment4 pages, 4 figures, Proceedings of the 30th ICRC, Merida, Mexico, 2007

References in corpus (1)

• Study of the Cosmic Ray Composition above 0.4 EeV using the Longitudinal Profiles of Showers observed at the Pierre Auger Observatory

Cited by in corpus (5)

• The microphysics of collisionless shock waves
• Blazars as Ultra-High-Energy Cosmic-Ray Sources: Implications for TeV Gamma-Ray Observations
• Galaxy Clusters as Reservoirs of Heavy Dark Matter and High-Energy Cosmic Rays: Constraints from Neutrino Observations
• On Gamma Ray Burst and Blazar AGN Origins of the Ultra-High Energy Cosmic Rays in Light of First Results from Auger
• Origin of ultra-high energy cosmic rays in the era of Auger and Telescope Array