Abstract
Several experiments around the world, like the ground-based observatories Pierre Auger and Telescope Array, and soon the space telescope JEM-EUSO, are investigating ultra-high-energy cosmic rays, trying to solve the mystery of their origin. The mass composition of these particles is a key piece of information crucial for a better understanding of the problem. Yet it cannot be observed directly but rather inferred from the simultaneous measure of the energy \(E_0\) of the primary particle and the atmospheric depth \(X_{\mathrm{max}}\) of its shower maximum. The conversion of (\(E_0, X_{\mathrm{max}}\)) into a primary mass can only be achieved by air-shower simulation. The paper investigates this question through detailed Monte Carlo calculations of air showers initiated by ultra-high-energy cosmic rays of \(10^{18}\)–\(10^{20}\) eV. The calculations were carried out using the code CONEX in combination with different up-to-date hadronic interaction models. The obtained results are compared to the most recent data from the current experiments.
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References
Aab A., et al. 2014, Phys. Rev. D, 90, 122006
Aab A., 2015a, Astrophys. J., 802, 111
Aab A., 2015b, Nucl. Instrum. Meth. Phys. Res. A, 798, 172
Aab A., 2017, Science, 357, 1266
Abbasi R. U., et al. 2014, Astrophys. J. Lett., 790, L21
Abbasi R. U., et al. 2015, Astropart. Phys., 64, 49
Abbasi R. U., et al. 2018, Astrophys. J., 858, 76
Abraham J., et al. 2010a, Phys. Rev. Lett., 104, 091101
Abraham J., et al. 2010b, Phys. Rev. B, 685, 239
Abu-Zayyad T., et al. 2012, Nucl. Instrum. Meth. Phys. Res. A, 689, 87
Abu-Zayyad T., et al. 2013, Astrophys. J. Lett., 768, L1
Adams J. H., et al. 2013, Astropart. Phys., 44, 76
Ahn E.-J., et al. 2009, Phys. Rev. D, 80, 094003
Allard D., et al. 2008, J. Cosmol. Astropart. Phys., 0810, 033
Alves Batista R., et al. 2019, Front. Astron. Space Sci., 6, 23
Anchordoqui L. A. 2019, Phys. Rep., 801, 1
Anchordoqui L. A., et al. 2020, Phys. Rev. D, 101, 023012
Bass S., et al. 1998, Prog. Part. Nucl. Phys., 41, 225
Bergmann T., et al. 2007, Astropart. Phys., 26, 420
Bird D. J., et al. 1995, Astrophys. J., 441, 144
Castellina A., et al. 2019, Proc. 36th Int. Cosmic Ray Conf., PoS(ICRC2019)004
Drescher H. J., Farrar G. R. 2003, Phys. Rev. D, 67, 116001
Engel J., et al. 1992, Phys. Rev. D, 46, 5013
Fletcher R., et al. 1994, Phys. Rev. D, 50, 5710
Gaisser T. 1990, Cosmic rays and particle physics (Cambridge: Cambridge University Press)
Gaisser T., Hillas A. 1977, Proc. 15th Int. Cosmic Ray Conf. (ICRC), 8, 353
Greisen K. 1966, Phys. Rev. Lett., 16, 748
Hanlon W., et al. 2018, JPS Conf. Proc., 19, 011013
Heck D., et al. 1998, Tech. Rep. 6019, Forschungszentrum Karlsruhe
Kalmykov N., et al. 1997, Nucl. Phys. B (Proc. Suppl.), 52, 17
Linsley J. 1963, Phys. Rev. Lett., 10, 146
Mollerach S., Roulet E. 2018, Prog. Part. Nucl. Phys., 98, 85
Ostapchenko S. 2011, Phys. Rev. D, 83, 014018
Ostapchenko S. 2014, Phys. Rev. D, 89, 074009
Pierog T., et al. 2006, Nucl. Phys. B Proc. Suppl., 151, 159
Pierog T., et al. 2015, Phys. Rev. D, 92, 034906
Sarazin F., et al. 2019, Bull. Am. Astrom. Soc., 51, 93
Yushkov A. 2019, Proceedings of the 36th International Cosmic Ray Conference, Madison, U.S.A PoS 482
Zatsepin G. T., Kuz’min V. A. 1966, J. Exp. Theor. Phys. Lett., 4, 78
Zyla P. A., et al. 2020, Prog. Theor. Exp. Phys., 083C01
Acknowledgements
We gratefully acknowledge the CORSIKA/CONEX team for making public their excellent simulation code, and for their assistance and support. We also wish to express our thanks to Dr Ralph Engel and Dr Ralf Ulrich from Karlsruhe Institute of Technology (KIT) for welcoming one of the authors during a training period on CORSIKA/CONEX at KIT.
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Lakel, G., Talai, M.C. & Attallah, R. Numerical study of the composition of ultra-high-energy cosmic rays. J Astrophys Astron 42, 108 (2021). https://doi.org/10.1007/s12036-021-09782-8
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DOI: https://doi.org/10.1007/s12036-021-09782-8