Muon content in air showers between 10 PeV and 1 EeV determined from measurements with KASCADE-Grande

Abstract

Muons in extensive air showers (EAS) are a sensitive probe for the primary cosmic ray mass and the physics of hadronic interactions at very high energies, hence it is important to precisely measure and carefully analyze this particular shower component. In practice, however, such measurements are difficult to carry out due to the penetrating nature of muons and their low density in the shower. This way just in a few experimental facilities the shower muon component has been measured event-by-event in combination with other EAS observables. One of them was the multicomponent air shower experiment KASCADE-Grande, which was designed to study cosmic rays in the energy interval from 1 PeV to 1 EeV and was located at the site of the Karlsruhe Institute of Technology, Germany at 110 m a.s.l. In this work, we will present an analysis of the KASCADE-Grande data in terms of the muon content (E µ > 230 MeV) of cosmic-ray induced air showers as a function of the primary energy (E = 10 PeV −1 EeV) and the zenith angle (< 35 •). We test also the predictions on the shower muon content of the post-LHC hadronic interaction models EPOS-LHC, QGSJET-II-04, SIBYLL 2.3 and SIBYLL 2.3c by comparing the model expectations with experimental results.

Lateral density distributions of muons and electrons in EAS from the KASCADE-Grande data for different zenith angle intervals.

“…We applied several quality cuts to diminish the systematic uncertainties, in particular, we only considered events obtained during stable data acquisition periods with no hardware problems [5]. We also kept events with shower cores located within the limits of a central area of 2.25×10 5 m 2 for radial distances in a range of = [150 m, 650 m] from the center of KASCADE array (see figure 1).…”