Centrality Dependence Of J/Psi Production In Au+Au And Cu+Cu Collisions By The Phenix Experiment At Rhic

J/psi production has been measured in Au+Au and Cu+Cu collisions at root(NN)-N-S = 200 GeV by the PHENIX experiment at the relativistic heavy ion collider (RHIC) during 2004 and 2005, respectively, at mid-rapidity (vertical bar eta vertical bar <= 0.35) via J/psi -> e(+) e(-) decay and at forward rapidity (1.2 <= vertical bar eta vertical bar <= 2.2) via J/psi -> mu(+) mu(-) decay. The nuclear modification factor (R-AA) of J/psi is presented as a function of the collision centrality for Au+Au collisions (final results) and Cu+Cu collisions (preliminary results) in both rapidity windows. These results are compared to SPS results at lower energy and to various theoretical calculations.