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Estimate of the Mass Composition of Ultrahigh Energy Cosmic Rays

A. A. Mikhailov·N. N. Efremov·N. S. Gerasimova·I. T. Makarov·G. V. Nikolayeva·G. G. Struchkov
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Abstract

It is proposed a new approach for estimating the composition of cosmic rays. It is found that the zenith angle distributions and muon components of EAS for energies E>10^19 eV and E>4.10^19 eV differ from each other. It is shown that the cosmic rays above E>4.10^19 eV is heavier than the cosmic rays at energy E~ 10^19 eV. According to our estimation the SUGAR array detected 8 showers above 10^20 eV. It is concluded that no sign of Greisen-Zatsepin-Kuzmin (GZK) cut off in the spectrum of cosmic rays and all cosmic rays are galactic.

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A. A. Mikhailov, N. N. Efremov, N. S. Gerasimova, I. T. Makarov, G. V. Nikolayeva, G. G. Struchkov. 2005-07-28. Estimate of the Mass Composition of Ultrahigh Energy Cosmic Rays. https://arxiv.org/abs/astro-ph/0507681

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