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arXiv · 1804.11202

Proton Fraction in PCR Mass Composition at Energies of 10^15-10^17 eV (Experiment {\guillemotleft}Pamir{\guillemotright})

Z. M. Guseva·E. A. Kanevskaya·J. Kempa·V. M. Maximenko·R. A. Mukhamedshin·S. E. Pyatovsky·V. S. Puchkov·S. A. Slavatinsky
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Abstract

The fraction of halo events among gamma-hadron families with SUM(Egamma) > 500 TeV is analyzed. The comparison of experimental data and Monte-Carlo simulations by MC0 code of quark-gluon string model under various assumptions on the PCR mass composition suggests a slowly increasing contribution of nuclei heavier than protons and alpha-particles to PCR mass composition. Effective atomic number of PCR particles changes in the energy interval 10^15-10^17 eV so that lnA grows from 2 to 2.5.

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Z. M. Guseva, E. A. Kanevskaya, J. Kempa, V. M. Maximenko, R. A. Mukhamedshin, S. E. Pyatovsky, V. S. Puchkov, S. A. Slavatinsky. 2018-04-26. Proton Fraction in PCR Mass Composition at Energies of 10^15-10^17 eV (Experiment {\guillemotleft}Pamir{\guillemotright}). https://arxiv.org/abs/1804.11202

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