High-energy multiple muons viewed from the observation of gamma-ray families at mountain altitude

Based on the knowledge of the nature of primary cosmic rays inferred from the observations of gamma-ray family events with the large-scale emulsion chamber experiments at Mt. Fuji and at Mt. Kanbala, the three-dimensional Monte Carlo simulation on the high-energy multiple-muon events has been carried out. By comparing the simulation results with the composition of primary cosmic rays being heavy-nuclei dominant, is quite consistent with the observed results on the lateral spread of multiple-muon events