The study of the muon content in extensive air showers (EAS) is relevant for understanding the origin and nature of cosmic rays. Moreover, muons serve as a sensitive observable to hadronic interactions in air showers, offering insight into high-energy physics processes. However, discrepancies between measured and predicted shower muon content have been reported by some EAS observatories, hinting to deficiencies of high-energy hadronic interaction models. In this work, we study the muon content of EAS with KASCADE-Grande data for primary energies between 10 PeV and 1 EeV, considering showers with zenith angles of θ ≤ 40°. In particular, we estimate the local muon density at fixed radial distances from the shower core and explore its dependence on atmospheric depth. Adapting the energy scale from the Pierre Auger Observatory (PAO) we compare the data against predictions of the QGSJet-II-04, EPOS-LHC and SIBYLL-2.3d hadronic interaction models. While good agreement is found in a large parameter space, a discrepancy between the measured and predicted local muon densities can be seen, especially for high primary energies and vertical events and here increasing for large radial distances of the measured muons from the EAS core. This could indicate an inadequate description of the attenuation of muons in the atmosphere.
César et al. (2025) studied this question.