Air showers, hadronic models, and muon production

We report on a study about some characteristics of muon production during the development of extended air showers initiated by ultra-high-energy cosmic rays. Using simulations with the recent new version of the AIRES air shower simulation system, we analyze and discuss on the observed discrepancies between experimental measurements and simulated data.Comment: Presented at UHECR 2018 (Paris, Oct 2018

Characterization of the atmospheric depth profile using the ground-level temperature: The case of Malargüe, Argentina

We present a study of the atmospheric depth profile and the dependence with its characteristic parameters. We introduce a new model, named GAMMA, based on a parameterization that allows us to obtain the atmospheric depth profile specifying only one simple physical parameter, namely the temperature at ground. The GAMMA model consists of a multilayer representation of the atmosphere that can be adjusted conveniently via constrained fits that are built to ensure interlayer continuity for both atmospheric depth and density profiles. Our analysis uses experimental data collected at Malargüe, Argentina by meteorological radiosondes. The GAMMA model can reproduce the averaged atmospheric depth profiles in all the cases available for analysis with good accuracy. The relative differences between model predictions and averaged data are always less than approximately 0.7%.Fil: Moreno, Juan Cruz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Física; ArgentinaFil: Sciutto, Sergio Juan. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Física; Argentin

Muon Bremsstrahlung and Muonic Pair Production in Air Showers

The objective of this work is to report on the modifications in air shower development due to muon bremsstrahlung and muonic pair production. In order to do that we have implemented new muon bremsstrahlung and muonic pair production procedures in the AIRES air shower simulation system, and have used it to simulate ultra high energy showers in different conditions. The influence of the mentioned processes in the global development of the air shower is important for primary particles of large zenith angles, while they do not introduce significant changes in the position of the shower maximum.Comment: To be presented at the International Symposium on Very High Energy Cosmic Ray Interactions X

Influence of diffractive interactions on cosmic ray air showers

A comparative study of commonly used hadronic collision simulation packages is presented. The characteristics of the products of hadron-nucleus collisions are analyzed from a general perspective, but focusing on their correlation with diffractive processes. One of the purposes of our work is to give quantitative estimations of the impact that different characteristics of the hadronic models have on air shower observables. Several sets of shower simulations using different settings for the parameters controlling the diffractive processes are used to analyze the correlations between diffractivity and shower observables. We find that the relative probability of diffractive processes during the shower development have a non negligible influence over the longitudinal profile as well as the distribution of muons at ground level. The implications on experimental data analysis are discussed