Characteristic features of EAS in the energy range of 50–500 PeV by the Yakutsk data

Data for the electron-photon, the muon and Cerenkov components of EAS, registered with the Yakutsk array during long data collection periods, are presented. The data appear of specific interest as control samples for the development of advanced hadronic interaction models and for checks of differences of various types of models (scaling procedures — QCD inspired models). Preliminary results of the analysis exhibit a satisfactory description of the experimental observations above 10 18 eV by scaling violation, and they require slightly larger multiplicities of the secondary particle production in the energy range of 50 – 500 PeV. The results appear also to be in agreement with a mixed composition in this energy range, approximately like that known for primaries of 10 12 eV. This conclusion is also consistant with the frequency of muons (≥ 1 GeV), observed at 300 m distance from the core of 50 – 500 PeV EAS.