Measurements and tests of hadronic interactions at ultra-high energies with the Pierre Auger Observatory

L. CAZON; THE PIERRE AUGER COLLABORATION.; S. J. SCIUTTO

Simposio; International Symposium on Ultra High Energy Cosmic Rays UHECR 2018; 2018

Extensive air showers are complex objects, resulting of billions of particle reactions initiated bysingle cosmic ray at ultra-high-energy. Their characteristics are sensitive both to the mass of the primary cosmicray and to the details of hadronic interactions. Many of the interactions that determine the shower features occurin kinematic regions and at energies beyond those tested by human-made accelerators.We will report on the measurement of the proton-air cross section for particle production at a center-of-massenergy per nucleon of 39 TeV and 56 TeV. We will also show comparisons of post-LHC hadronic interactionmodels with shower data by studying the moments of the distribution of the depth of the electromagneticmaximum, the number and production depth of muons in air showers, and finally a parameter based on the risetimeof the surface detector signal, sensitive to the electromagnetic and muonic component of the shower. Whilethere is good agreement found for observables based on the electromagnetic shower component, discrepanciesare observed for muon-sensitive quantities.