On the interpretation of the cosmic-ray anisotropy at ultra-high energies

Abstract

A natural interpretation of the correlation between nearby Active Galactic Nuclei (AGN) and the highest-energy cosmic rays observed recently by the Pierre Auger Collaboration is that the sources of the cosmic rays are either AGN or other objects with a similar spatial distribution (the ``AGN hypothesis''). We question this interpretation. We calculate the expected distribution of the arrival directions of cosmic rays under the AGN hypothesis and argue that it is not supported by the data, one of manifestations of the discrepancy being the deficit of events from the direction of the Virgo supercluster. We briefly discuss possible alternative explanations including the origin of a significant part of the observed events from Cen A.

arXiv comment12 pages, 3 figures

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• Astrophysical implications of hypothetical stable TeV-scale black holes
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• Ultra-High Energy Cosmic Ray production in the polar cap regions of black hole magnetospheres
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• Mapping the most energetic cosmic rays
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• Lorentz symmetry violation and the results of the AUGER experiment
• Problems in High Energy Astrophysics
• Anisotropy Studies with the Pierre Auger Observatory
• Search for Nuclei Sources in the Ultra-High Energy Cosmic Ray Data