Frozen motion model and dilepton production from 200A GeV S+W collisions at CERN SPS

Abstract

We have analysed the invariant mass distribution of dileptons in S+W collisions at 200A GeV as measured by the HELIOS-3 collaboration at CERN SPS. Three scenarios were considered where the collision lead to formation of (i) the quark-gluon plasma, (ii) the ideal hot hadron gas and (iii) the viscous hot hadron gas. The space-time evolution was governed by the minimal extension of the Bjorken hydrodynamics. All the three scenarios indicate excess dileptons in the experiment.