Centrality, rapidity and transverse momentum dependence of the J/\(psi\) suppression in Pb-Pb collisions at \(\sqrt{s_{NN}}\)=2.76 TeV

Abstract

The inclusive J/\).psi\) nuclear modification factor \(R_{AA}\) in Pb-Pb collisions at \(\sqrt{s_{NN}}\).2.76TeV has been measured by ALICE as a function of centrality in the \(e^+e^-\) decay channel at mid-rapidity |y| < 0.8 and as a function of centrality, transverse momentum and rapidity in the \(\mu^+\mu^-\) decay channel at forward-rapidity 2.5 < y < 4.The J/\).psi\) yields measured in Pb-Pb are suppressed compared to those in pp collisions scaled by the number of binary collisions.The \(R_{AA}\) integrated over a centrality range corresponding to 90% of the inelastic Pb-Pb cross section is 0.72 +- 0.06 (stat.) +- 0.10 (syst.) at mid-rapidity and 0.57 +- 0.01 (stat.) +- 0.09 (syst.) at forward-rapidity. At low transverse momentum, significantly larger values of \(R_{AA}\) are measured at forward-rapidity compared to measurements at lower energy.These features suggest that a contribution to the J/\).psi\) yield originates from charm quarks (re)combination in the deconfined partonic medium.