Experimental studies of the muonic component of extensive air showers

• Ano de defesa: 2018
• Autor(a) principal: Prado, Raul Ribeiro
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Instituição de defesa: Biblioteca Digitais de Teses e Dissertações da USP
• Palavras-chave em Português: Air shower physics; Chuveiros atmosféricos extensos; Componente muônica de chuveiros atmosféricos; Extensive air showers; Física de chuveiros atmosféricos; Muonic component of air showers; Raios cósmicos de altas energias; Ultra-high energy cosmic rays
• Link de acesso: http://www.teses.usp.br/teses/disponiveis/76/76131/tde-21062018-150629/

Ultra-High Energy Cosmic Rays (UHECR) can only be measured by the detection of Extensive Air Showers (EAS) created by the interaction of the cosmic ray particle with an atmospheric nuclei. The inference of some of the properties of UHECR, like their mass composition, is only possible by the comparison of measurements of EAS observables to predictions from Monte Carlo simulations. The most important source of uncertainties on the description of EAS by the simulations is the modeling of hadronic interactions. For many years it has been known that the hadronic interaction models fail on predicting the EAS observables related to their muonic component. The most evident manifestation of that is called muon deficit problem due to the fact that the number of muons in EAS with energies above 1018 eV predicted by simulations is smaller than the observed ones. The aim of this thesis is to approach this problem in three distinct fronts. First, a method is developed to interpret measurements of number of muons in terms of cosmic rays composition in despite of the muon deficit problem. Second, an EAS observable which is sensitive to the muon energy spectrum at ground and, consequently, can be used to constrain hadronic interaction models is proposed and tested. Third and final, the muon production in air showers is studied through measurements of hadron production spectra in pion-carbon interactions.