Nuclear Interactions in Carbon Produced by Cosmic Rays with Energies between1010and1012ev

Abstract

An experiment is described in which high-energy nuclear interactions in the range of energies ${10}^{10}$-${10}^{12}$ ev were analyzed by means of a cloud chamber in a magnetic field. Measurements of ionization and momentum made possible the identification of electrons and $\pi$ mesons to about 20 Bev/c. Protons, $K$ mesons, and hyperons could not be identified unambiguously among themselves, except in very limited regions of momentum. The primary particles were cosmic-ray nucleons and a possible fraction of pions, the target nuclei were carbon and the velocities of the primaries were determined from balance of momentum in the center-of-mass system. A total of 41 events were analyzed, and the results compared to previous experimental work and the predictions of the theories of Heisenberg and Landau. The measurements made included the transverse momenta of the secondaries and their average energy in the center-of-mass system, the energy and angular distributions of the pions and heavy particles (protons, $K$ mesons, hyperons) in the center-of-mass system, the inelasticity of the collision, the multiplicity of the showers, the percentage of strange particles, and the positive excess of the secondaries.