Production de <i>J</i>/ψ dans les collisions de proton, oxygène et soufre sur cibles lourdes, à 200 GeV/N

The production of J/ψ at 200 GeV/N, in proton, oxygen, and sulfur collisions with copper and uranium targets has been studied by the NA38 collaboration. When the energy density reached in the collisions increases a suppression of the muon pairs coming from the J/ψ disintegration, relative to those from the continuum, is observed. This relative suppression is stronger when the J/ψ transverse momentum is smaller.[Journal translation]