Dr. Abd El Nasser Saber Abd El Fatah :: Publications:

Many results obtained from studying the angular distributions of heavy fragments emitted from interaction of silicon nucleus with composite target nuclei of emulsion at collision energy 14.6 A GeV per nucleon. The angular distributions of grey and black secondary charged produced fragments are well described through statistical model. The average emission angle is 〖64〗^° for grey particles and 〖82〗^° for black particles that are nearly constant for different projectiles in range of collision energy 2.2 to 14.6 A GeV. The predicted rational velocity by statistical model χ_o which describe the system responsible for production of secondary particle is nearly equal to 0.5 for grey particles and tends to be ~0.13 for black particles. The velocity of the emitting system described by parameter β//, where the emitting system for grey particles is fast with typical longitudinal velocities β//g ~ 0.13-0.20 while it slow for emission black particle in the range β//b~0.008-0.019. The temperatures of the system responsible for emission of secondary slow fragments are found to be 58 and 6 MeV for fast grey and slow heavy fragments respectively. The angular distributions of slow fragments, grey and black particles show clear dependence on size of target nucleus. Most probable emission angles are in forward direction for interactions with light nuclei while it becomes symmetry around the middle angle for interactions with heavy nuclei. The emission system of these particles becomes slower and low temperature with increasing mass number of the interacting target nucleus.