The interpretation of extensive air shower (EAS) measurements often requires the comparison with EAS simulations based on high-energy hadronic interaction models. These interaction models have to extrapolate into kinematical regions and energy ranges beyond the limit of present accelerators. Therefore, it is necessary to test whether these models are able to describe the EAS development in a co...

Using the large hadron calorimeter of the KASCADE experiment, hadronic cores of extensive air showers have been studied. The hadron lateral and energy distributions have been investigated in order to study the reliability of the shower simulation program CORSIKAwith respect to particle transport, decays, treatment of low-energy particles, etc. A good description of the data has been found at la...

Hadronic interaction models are a core ingredient of simulations extensive air showers and pose the major source uncertainties predictions shower observables. Recently, Pythia~8, hadronic model popular in accelerator-based high-energy physics, became usable as well. We have integrated Pythia~8 with its new capabilities into simulation framework CORSIKA~8. First results show significantly shallo...

A model based on the hadronic fluctuations of the real photon is developed to describe the total photonucleon and photonuclear cross sections in the energy region above the nucleon resonances. The hadronic spectral function of the photon is derived including the finite width of vector-meson resonances and the quark-antiquark continuum. The shadowing effect is evaluated considering the effective...

A model based on the hadronic fluctuations of the real photon is developed to describe the total photonucleon and photonuclear cross sections in the energy region above the nucleon resonances. The hadronic spectral function of the photon is derived including the finite width of vector-meson resonances and the quark-antiquark continuum. The shadowing effect is evaluated considering the effective...

The status of present theoretical description of very high energy hadronic interactions is reviewed. The impact of new results of accelerator and cosmic ray experiments on hadronic interaction model constructions is discussed in detail. Special attention is payed to remaining uncertainties in model extrapolations into the ultra-high energy domain, in particular, concerning model predictions for...

The leading contribution to the uncertainties of atmospheric neutrino flux calculations arise from cosmic-ray nucleon and production cross sections secondary particles in hadron-air interactions. data-driven model developed this work parametrizes particle yields fixed-target accelerator data. propagation errors data inclusive muon predictions results smaller than previous estimates, description...