Classical and quantum signatures of quark-gluon plasma formation in relativistic heavy ion collisions

Production mechanism of centrally-produced J/ψ particles in heavy ion collisions localizes the initial quark-antiquark pair within a spacetime region much smaller than the size of the observed bound state. The time evolution of the state then requires spreading wave packets with substantial relativistic components. Calculations of survival probability due to initial color force screening in a quark-gluon plasma are compared with that obtained when assuming classical motion of the quarks. Crucial differences are found in the characteristic dependence on transverse momentum, which will have significant impact on interpretation of future data. (author) 6 refs., 4 figs