Hadron multiplicities in nucleus--nucleus interactions are calculated in the
Dual Parton Model and its dependence on the number of collisions and the number
of participants is analyzed. Shadowing corrections are calculated as a function
of impact parameter and the multiplicity per participant as a funtion of
centrality is found to be in agreement with experiment at SPS and RHIC
energies. The obtained results are used to compute the J/ψ suppression in
a comover approach.Comment: 4 pages, 4 postscript figures. Talk given at XXXVI Rencontres de
Moriond, Les Arcs, France, March 200