Short-distance QCD is employed to calculate the J/ψ survival probability in an equilibrating parton gas whose evolution is governed by a set of master rate equations. Partons in the early stage of high-energy nuclear collisions may initially not be in equilibrium, but their average transverse momentum is sufficiently high to break up a QQ¯ bound state. Such a breakup during the evolution of the parton gas is shown to cause a substantial J/ψ suppression at both RHIC and LHC energies, using realistic estimates of the initial parton densities. The transverse momentum dependence of the suppression is also shown to be sensitive to the initial conditions and the evolution history of the parton plasma. © 1996 The American Physical Society.

• Received 27 November 1995

DOI:https://doi.org/10.1103/PhysRevC.53.3051