Hadronic interactions at energies around 103 TeV inferred from the large-scale emulsion-chamber experiment at Mt. Fuji

Details of experimental results, obtained with large-scale emulsion chambers at Mt. Fuji (3776 m above sea level), are presented. The experimental data, which is sensitive to hadronic interactions at energies around 103 TeV, is compared with Monte Carlo simulations based on various assumed interaction models and primary particles. The results may be briefly summarized as follows. (1) Scaling in the fragmentation region can be valid up to at least 103 TeV only if the primary particles are mixed with significant amounts of heavy nuclei at energies over 1014 eV. (2) Cross sections should continue to increase with energy up to 103 TeV, at least, at almost the same rate as that obtained at lower energies. (3) There exists some evidence to indicate remarkable production of particles or jets with high Pt of several GeV/c at energies around 103 TeV. (4) Hadron-to - ray ratios in the observed family events remain almost within the scope of simulation prediction. Other interesting characteristics of family events are also discussed.