Meson Showers and High-Energy Interactions in Light and Heavy Nuclei

A study has been made of nuclear disintegrations produced in electron-sensitive emulsions exposed to cosmic radiation at 80 000 ft. Of 93 stars containing more than three shower particles, 29 were interpreted as being induced in the light nuclei C, N, O, and 64 in the heavy nuclei Ag and Br. The low-energy tracks appear to be emitted isotropically from a slowly moving nucleus and the forward collimation of the remaining tracks is discussed. The average numbers of shower particles from the heavy and light nuclei are 7.7 and ${6.4}_5$, respectively, and it is shown that these figures are consistent with multiple processes of meson production. The difference between the angular distributions of shower particles from heavy and light nuclei is discussed on the assumption that it is mainly due to scattering.