Backward slow protons production in the inelastic interactions of Li and Li nuclei with emulsion nuclei at Dubna energy
M. El-Nadi1 - A. Abdelsalam1 - N. Ali-Mossa2 - Z. Abou-Moussa1 - S. Kamel1 - Kh. Abdel-Waged3 - W. Osman1 - B. Badawy1
1 Physics Department, Faculty of Science, Cairo University, Egypt
2 Basic Science Department, Faculty of Engineering, Shoubra, Egypt
3 Physics Department, Faculty of Science, Benha University, Egypt (E-mail: Khelwagd@frcu.eun.eg)
Received: 25 August 1997 / Revised version: 5 May 1998 Communicated by C. Signorini
We report the experimental measurements on the multiplicity of slow target associated particles, in the forward () and backward () hemispheres, and the different correlations between the backward slow protons and the production of hadrons in both hemispheres in the interactions of 6Li(3.7 A GeV) and 7Li(2.2 A GeV) with emulsion nuclei. The study of the number of backward slow protons (Nbb and Nbg) indicates that while the number of backward black particles, Nbb, is a good factor representing the purely target fragments, the number of backward grey particles, Nbg, can be considered as an accurate experimental factor for the impact parameter dependence of the collision. It is also shown that the most central collisions are events having Nbg>0 and Nbs>0. We confront the data with a multiple scattering model incorporating both binary cascading and evaporation of residual nucleus. The model applies well in the region of limited cascading (backward hemisphere). As for the forward hemisphere, where cascading becomes more branched, the model becomes less applicable.
25.70.Mn Projectile and target fragmentation - 25.75.-q Relativistic heavy-ion collisions