The inclusive J/ψ nuclear modification factor RAA in Pb-Pb collisions at √s(NN)=2.76 TeV 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 μ+μ− decay channel at forward-rapidity 2.5<y<4.The J/ψ yields measured in Pb-Pb are suppressed compared to those in pp collisions scaled by the number of binary collisions. The RAA 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 RAA are measured at forward-rapidity compared to measurements at lower energy. These features suggest that a contribution to the J/ψ yield originates from charm quarks (re)combination in the deconfined partonic medium.
Centrality, rapidity and transverse momentum dependence of J/Psi suppression in Pb-Pb collisions at √s(NN)=2.76TeV
DE CARO, ANNALISA;DE GRUTTOLA, DANIELE;DE PASQUALE, Salvatore;FUSCO GIRARD, Mario;PAGANO, PAOLA;VIRGILI, Tiziano;CALIVA', Alberto
2014-01-01
Abstract
The inclusive J/ψ nuclear modification factor RAA in Pb-Pb collisions at √s(NN)=2.76 TeV 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 μ+μ− decay channel at forward-rapidity 2.5I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.