A QUANTITATIVE-ANALYSIS OF CHARMONIUM SUPPRESSION IN NUCLEAR COLLISIONS

Data from J/psi and psi(1). production in p - A collisions are used to determine the cross section for absorption of pre-resonance charmoniu m in nuclear matter. The J/psi suppression in O - Cu, O - U and S - U collisions is fully reproduced by the corresponding nuclear absorption , while Pb - Pb collisions show an additional suppression increasing w ith centrality. We study the onset of this change in terms of hadronic comover interactions and conclude that so far no conventional hadroni c description can consistently account for all data. Deconfinement, st arting at a critical point determined by central S-U collisions, is in accord with the observed suppression pattern.