A comprehensive study of shower to shower fluctuations

P.M. Hansen (1) , J. Alvarez-Muñiz (2) , R.A. Vázquez (2)

1 Departamento de Fisica
2 Facultade de Física

By means of Monte Carlo simulations of extensive air showers (EAS), we have performed a comprehensive study of the shower to shower fluctuations affecting the longitudinal and lateral development of EAS. We split the fluctuations into physical fluctuations and those induced by the thinning procedure customarily applied to simulate showers at EeV energies and above. We study the influence of thinning on the calculation of the shower to shower fluctuations in the simulations. For thinning levels larger than =10 - 10, the determination of the shower to shower fluctuations is hampered by the artificial fluctuations induced by the thinning procedure. However, we show that shower to shower fluctuations can still be approximately estimated, and we provide expressions to calculate them. The influence of fluctuations of the depth of first interaction on the determination of shower to shower fluctuations is also addressed.

Mots clés: Cosmic rays; Extensive air showers; Ground detector; Simulation; Muon component; Electromagnetic component

Domaines: Cosmologie et astrophysique extra-galactique [astro-ph.CO]; Cosmologie et astrophysique extra-galactique [astro-ph.CO]

P.M. Hansen, J. Alvarez-Muñiz, R.A. Vázquez. A comprehensive study of shower to shower fluctuations. Astroparticle Physics, 2010, 34 (6), pp.503. ⟨10.1016/j.astropartphys.2010.11.001⟩. ⟨hal-00710472⟩