Air Shower Development and Pion Interactions in the EPOS Model

In detailed air shower simulations, the uncertainty in the prediction of shower observable for different primary particles and energies is currently dominated by differences between hadronic interaction > models. With the results of the first run of the LHC, the difference between post-LHC model predictions has been reduced at the same level than experimental uncertainties of cosmic ray experiments. At the same time new type of air shower observable, like the muon production depth, has been measured adding new constraints on hadronic models. Currently no model is able to reproduce consistently all mass composition measurement possible within the Pierre Auger Observatory for instance. Using new modifications in EPOS and LHC data, we will show how air shower measurements can be used to constrain pion-air interactions in kinematic phase space which cannot be tested by laboratory experiments. The goal being a model which can reproduce all primary mass composition measurements from air showers in a consistent way.