Muon Bundle Multiplicities in Deep Underground Detectors as a Probe of Pion-Air Interactions

by Dr Karolin Hymon

Wednesday 13 May 2026, 16:00 → 17:00 Europe/Berlin

CP-03-123 (TU Dortmund)

Several air shower experiments report a deficit of muons relative to simulation at ultra-high energies, with the discrepancy growing with energy, while other experiments observe no significant deficit depending on detector type and distance to the shower axis. Muon fluctuations and shower maximum X_max are consistent with hadronic model predictions, disfavoring the primary interaction as cause of the energy-dependent deficit. This points to secondary interactions accumulating through the cascade, in particular inelastic interactions of pions with air nuclei, which cannot be measured directly at colliders in the relevant energy range. In this talk, I will present a novel measurement approach to constrain the energy-dependence of the inelastic pion-air cross section using muon bundle multiplicities in deep-underground Cherenkov detectors, such as IceCube or KM3NeT.