Differential studies of inclusive J/ψ and ψ(2S) production at forward rapidity in Pb-Pb collisions at √sNN = 2.76 TeV

Abstract

The production of J/ and (2S) was studied with the ALICE detector in Pb-Pb collisions at the LHC. The measurement was performed at forward rapidity (2:5 < y < 4) down to zero transverse momentum (pt) in the dimuon decay channel. Inclusive J/ yields were extracted in di erent centrality classes and the centrality dependence of the average pt is presented. The J/ suppression, quanti ed with the nuclear modi cation factor (RAA), was measured as a function of centrality, transverse momentum and rapidity. Comparisons with similar measurements at lower collision energy and theoretical models indicate that the J/ production is the result of an interplay between color screening and recombination mechanisms in a decon ned partonic medium, or at its hadronization. Results on the (2S) suppression are provided via the ratio of (2S) over J/ measured in pp and Pb-Pb collisions.