SIZING UP THE NUCLEAR GLUE IN J PSI-PRODUCTION/

Nuclear gluon densities are of great importance to the physics of rela tivistic heavy ion collisions, in particular, in assessing the origin of J/psi-suppression. We describe our attempts to distinguish various models of the gluonic EMC-effect, using the existing J/psi-production data in proton-nucleus collisions. We find that no model is capable of explaining all the features of the high precision E772 data although the overall trend suggests this to be more a matter of fine-tuning the models than the presence of new physical effects.