In this experimental work, the projectile fragmentation of 3.7A GeV 16O interaction with emulsion nuclei is investigated. Throughout a total scanned length of 195.58 meters, 1540 inelastic interactions are picked up. The measured mean free path is 12.70±0.33 cm, which corresponds to interaction cross-section = 988 ±25 mb. This value is compatible with those calculated on the basis of a geometrical consideration. The delta-ray counting method is used to identify the charge of each of projectile fragment. The delta ray distribution of each charge is fitted by a Gaussian shape. The fragmentation topology of 16O is presented and compared with that obtained in the interaction of 16O with emulsion nuclei at 60A GeV. The results show that the mechanism responsible for projectile fragmentation is independent of the projectile energy. The probabilities of the different produced projectile fragments indicate that the He is the most probable channel. This implies that 16O structure tends to have clustering behavior. This clustering effect is independent of the incident beam energy. The events associated with single nucleon participations are supposed to be due to a single charge particle or neutron stripped from the projectile. The multiplicity characteristics of particles produced from these events are compared with those due to p-Emulsion interaction at the same energy as well as the prediction of the cascade-evaporation model. The study shows that the interactions of these stripped nucleons occur only with a free or quasi free nucleon with the absence of cascading.

This thesis is concerned with analyses of the fast, and slow hadrons production, in 28Si-Em interactions at 14.6A GeV. The main motivation is the search for the effective mechanism responsible for this production. One key is the dependence of particle multiplicity on the projectile energy. In this species, 28Si -Em interactions at 3.7A GeV is used for comparison.