Interactions between Nuclei at 100-500 MeV/nucleon

Abstract

Nucleus-nucleus interactions produced by heavy cosmic ray primaries in nuclear emulsions have been analysed. The kinetic energy of the incident nuclei is 100-500 MeV/nucleon. Whenever possible the particles leaving the point of interaction have been identified and their emission angles and kinetic energies have been measured. The angular and energy distribution of the protons emitted can be understood if reasonable values of the momenta of the interacting nucleons inside the colliding nuclei are considered, and if it is further assumed that interactions between nucleons and clusters of nucleons occur. The momentum distribution of the emitted protons and alpha-particles is consistent with an average recoil momentum of the target nuclei of about 23 MeV/c per nucleon. It is found that about 30% of the particles with ranges in the interval 10 μm<R<100 μm cannot be explained by ordinary evaporation theory. The spallation of the target and the projectile has been studied. It was found that the disintegration of the two interacting nuclei increases with increasing projectile energy.