The ALICE experiment has measured the inclusive J/$\psi$ production in Pb-Pb collisions at $\sqrt{ s_{ \mathrm{ NN}} } = 2.76$ TeV down to zero transverse momentum in the rapidity range $2.5 < y < 4$. A suppression of the inclusive J/$\psi$ yield in Pb-Pb is observed with respect to the one measured in pp collisions scaled by the number of binary nucleon-nucleon collisions. The nuclear modification factor, integrated over the 0-80% most central collisions, is $0.545 \pm 0.032 \rm{ (stat.)} \pm 0.083 \rm{ (syst.)}$ and does not exhibit a significant dependence on the collision centrality. These features appear significantly different from measurements at lower collision energies. Models including J/$\psi$ production from charm quarks in a deconfined partonic phase can describe our data.

Categories: hep-ex nucl-ex

J/$\psi$ suppression at forward rapidity in Pb-Pb collisions at $\sqrt{s_{\rm NN}}$ = 2.76 TeV