CXXIV. Nuclear transmutations produced by cosmic-ray particles of great energy.—Part VI. Experimental results on meson production

Abstract

Summary An analysis has been made of the secondary particles ejected from nuclear disintegrations observed in electron sensitive emulsions exposed to the cosmic radiation at 68,000 ft. Scattering and grain density measure-ments have been carried out on the tracks of 2000 particles associated with these stars. In addition, the grain density and angular distribution of 3070 shower particles and 1508 “grey” tracks have been measured. For 200 stars, the energy of the primary particle which produced the disintegration was measured. A detailed analysis was made of such events. Single fast τ-mesons of kinetic energy less than 1 BeV. are found to interact strongly with nuclear matter. An estimate of the frequency of occurrence of neutral mesons was made from a consideration of the energy balance in stars of low multiplicity, n s .