Multiplicity and pseudorapidity distributions of charged particles from32S induced heavy ion interactions at 200A GeV

Abstract

Multiplicity and pseudorapidity distributions have been measured for S-32 + Al, Cu, Ag and Au at 200 A GeV. The widths of the pseudorapidity distributions increase from central to peripheral collisions. The main contribution is assumed to come from the increasing fraction of charged particles stemming from the fragmentation of the target for peripheral collisions as compared to central collisions. On the average 170-180 charged particles per unit of pseudorapidity are attained for the most central S-32 + Au events at the maximum of the distribution. The target dependence of the yield of charged particles for central collisions is investigated. In the target rapidity region the yield is directly proportional to the target mass. The transverse energy per charged particle has been studied as a function of centrality and pseudorapidity. The experimental results are compared to the results from the Monte-Carlo model VENUS 3.11 which includes rescattering among secondaries. A comparison between different centrality triggers is made.