Contribution of intermediate stage gluons to J/Psi suppression in Lead-Lead collisions at 158 AGeV

Abstract

We point out that dissociation of J/Psi by partons (mostly gluons) present in the intermediate stage of heavy-ion collisions can explain J/Psi suppression observed recently by the NA-50 Collaboration at the CERN-SPS in Pb-Pb interactions. Suppression by intermediate stage gluons represents an additional multiplicative factor to that given by Gerschel-Hufner mechanism. The agreement with data on J/Psi suppression both in light- ions induced nuclear collisions and in Pb-Pb interactions requires that the life-time of intermediate gluons increases with nucleon numbers of colliding nuclei. In our model the energy density of intermediate stage gluons in Pb-Pb collisions approaches for a short time the critical density.

Comments: 17 pp,Latex, 1 Table in Latex,1 Fig. in Latex, amended computations, conclusions unchanged, instead of "pre- equilibrium gluons" we refer to less ambiguous "intermediate stage gluons"