Recombinant charmonium in strongly coupled quark-gluon plasma

We update our previous work on a Langevin-with-interaction model for charmonium in heavy-ion collisions by considering the effect owing to recombination. We determine the contribution to J/ψ yields from c□c pairs whose constituent quarks originate from two different hard processes. Like the surviving J/ψ states, the recombinant J/ψ also undergo both a stochastic interaction, determined by a hydrodynamical simulation of the heavy-ion collision, and an interaction determined by the Q□Q potentials measured on the lattice for appropriate temperatures. From the results of these simulations, we determine both the direct and the recombinant contribution to the J/ψ yields for RHIC conditions and find that, for central collisions, between 30% and 50% of the J/ψ yield is caused by recombinant production. We compare our results with other models and look for how the recombinant contribution differs from the surviving contribution in the differential pT yields. Including the recombinant contribution improves the agreement with the latest analysis of charmonium at RHIC, which shows an absence of anomalous suppression except in the most central collisions.