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UHECR spectrum: the spatial distribution of the sources

Gustavo Medina Tanco
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Abstract

The Ultra-high energy cosmic ray energy spectrum summarized by the AGASA collaboration indicates clearly that the cosmic ray spectrum extends well beyond the Greisen-Zatsepin-Kuzmin (GZK) cut-off at \sim 5 x 10^19 eV. Furthermore, despite the small number statistics involved, some structure in the spectrum may be emerging. Using numerical simulations, it is demonstrated in the present work that these features are consistent with a spatial distribution of sources that follows the distribution of luminous matter in the local Universe. Therefore, from this point of view, there is no need for a second high-energy component of cosmic rays dominating the spectrum beyond the GZK cut-off.

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Gustavo Medina Tanco. 1999-05-19. UHECR spectrum: the spatial distribution of the sources. https://arxiv.org/abs/astro-ph/9905239

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