Interaction of 1.5-Bev NegativeπMesons with Emulsion Nuclei

Abstract
The energy spectrum of charged pion secondaries, produced from emulsion nuclei by bombardment with 1.5-Bev negative pions, has been measured. The spectrum was observed to be sharply peaked for pions of laboratory energies from 100 to 150 Mev. The mean pion energy was 148 Mev, and 75% of the pions were in the energy range from 50 to 150 Mev. The observed number of charged pions per star was 0.66. Half of the emulsion stars had no meson track, 36% had a single meson, 12% two mesons, and 2% more than two mesons. The experimental results have been compared with Monte Carlo nuclear cascade calculations.