INVESTIGATION OF INTERACTIONS OF HIGH-ENERGY PARTICLES WITH ATOMIC NUCLEI, AT MOUNTAIN ALTITUDES

A 10-m/sup 2/ counter array, with several layers of counters and Pb and C absorbers was used to study high-energy cosmic ray interactions at 3200 m, It was found that spectra of ionizing events depend strongly on the size of the apparatus. In the region from 3 x 10/sup 11/ to 10/sup 13/ ev the spectrum of events falls uniformly as the spectrum of nuclear-active particles, showing no breaks,'' Results show that pi /sup 0/-mesons take up a large share of the energy in the case of inelastic events. The measurement of pi /sup 0/-energy and the coefficient of inelasticity lead to excessive estimates of the initial particle energy. The integral spectrum of events caused by mu -mesons is exponential, with the exponent gamma = 2.22 plus or minus 0.14. At sea level mu -mesons generate ~70% of all ionizing events having --2 x 103 relativistic particles, and about 50% in the case of events having ~2 x 10/sup 4/ particles. (TTT)