Inclusive, prompt and non-prompt J/psi production at mid-rapidity in Pb-Pb collisions at root S-NN=2.76 TeV

Abstract

The transverse momentum (p(T)) dependence of the nuclear modification factor R-AA and the centrality dependence of the average transverse momentum LT p(T) GT for inclusive J/psi have been measured with ALICE for Pb-Pb collisions at root S-NN = 2.76TeV in the e(+)e(-) decay channel at mid-rapidity (vertical bar y vertical bar LT 0.8). The LT p(T) GT is significantly smaller than the one observed for pp collisions at the same centre-of-mass energy. Consistently, an increase of RAA is observed towards low p(T). These observations might be indicative of a sizable contribution of charm quark coalescence to the J/psi production. Additionally, the fraction of non-prompt J/psi from beauty hadron decays, f(B), has been determined in the region 1.5 LT p(T) LT 10 GeV/c in three centrality intervals. No significant centrality dependence of fB is observed. Finally, the RAA of non-prompt J/psi is discussed and compared with model predictions. The nuclear modification in the region 4.5 LT p(T) LT 10 GeV/c is found to be stronger than predicted by most models.