Dr. Tanguy Pierog (Karlsruhe Institute of Technology, Institute for Nuclear Physics)
"Recent results from Auger and KASKADE-Grande, and introduction to the CORSIKA air shower simulation code"
In recent years the interpretation of high energy cosmic ray measurements took another direction. From the astrophysical point of view, it was usually admitted that extra-galactic charged cosmic rays were protons, but mass composition results for the Pierre Auger Observatory, in particular using hadronic interaction models updated with LHC data, show that a mixed composition is observed at energies well above the ankle of the spectrum. Using these new models in the knee region for KASCADE-Grande data analysis lead to significant change in the mass composition as well. Realistic air shower simulation and hadronic interaction models are the key points for a proper interpretation of charged cosmic ray data. After a first part dedicated to the CORSIKA and CONEX air shower simulation models and EPOS LHC and QGSJETII-04 hadronic interaction models, the latest results from the KASCADE-Grande and Pierre Auger Observatory will be presented with a focus given on mass composition and constrains on hadronic interactions.