Muon pairs produced in Pb-Pb interactions at 158 GeV/c per nucleon are used
to study the transverse momentum distributions of the J/psi, psi' and dimu
ons in the mass continuum. In particular, the dependence of these distribut
ions on the centrality of the Pb-Pb collision is investigated in detail. (C
) 2001 Published by Elsevier Science B.V.