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Signatures of AGN model for UHECR

V. Berezinsky·A. Z. Gazizov·S. I. Grigorieva
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Abstract

We demonstrate that the energy spectra of Ultra High Energy Cosmic rays (UHECR) as observed by AGASA, Fly's Eye, HiRes and Yakutsk detectors, have the imprints of UHE proton interaction with the CMB radiation in the form of the dip at $E\sim 1\times 10^{19}$~ eV, of the beginning of the GZK cutoff, and of very good agreement with calculated spectrum shape. We argue that these data, combined with small-angle clustering and correlation with AGN (BL Lacs), point to the AGN model of UHECR origin at energies $E \lsim 1\times 10^{20}$ eV. The excess of the events at $E \gsim 1\times 10^{20}$ eV, which is observed by AGASA (but absent in HiRes data) can be explained by another component of UHECR, e.g. by UHECR from superheavy dark matter.

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V. Berezinsky, A. Z. Gazizov, S. I. Grigorieva. 2002-10-04. Signatures of AGN model for UHECR. https://arxiv.org/abs/astro-ph/0210095

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