CENTRAL COLLISIONS INDUCED BY LIGHT TARGET NUCLEI

Abstract

For the interactions of p, 3 He , 4 He , and 6 Li with emulsion at 4.5 A GeV/c, an experimental study has been performed. The type of interactions chosen was central, which enables to analyze a specific interaction mechanism. The selection of the central events has been in the framework of the particles emitted beyond the kinematic limits (θ Lab ≥90°). This selection provides a strict criterion to distinguish the central collisions. For the sake of comparison, an additional criterion is introduced. It deals with interactions that exhibit an absence of projectile fragmentation. A detailed study of the emitted pions multiplicity is presented. The focusing is on the light emulsion target H and CNO in comparison with the heavy AgBr . The analysis reveals that the occultation of light projectile nuclei is possible in CNO targets along with the complete occultation in AgBr .