Effects of gluon depletion on J/psi suppression in pA and AA collisions - art. no. 054611

The enhanced suppression of J/psi production at large x(F) in pA collisions is studied in the framework of gluon depletion at large x(1). The nonpertu rbative process that modifies the gluon distribution as the gluons propagat e in nuclear matter is described by an evolution equation with a kernal to be determined by phenomenology. With nuclear shadowing and antishadowing ta ken into account, the effect on the gluon distribution is shown to be a dep letion in excess of 40% at x(1)approximate to0.8 for A>100. There is a smal l amount of enhancement of the gluon distribution at small x(1), but it doe s not lead to any contradiction with the existing data on J/psi suppression in the central region. Extentions to psi' suppression and AB collisions ar e also investigated in the framework of gluon redistribution.