Dergi makalesi Açık Erişim

Overview of results on heavy flavour and quarkonia from the CMS collaboration

2013    Mironov, Camelia

The non-prompt J/psi from B-meson decays, the prompt J/psi, the inclusive psi' and the three Y states were measured separately using the Compact Muon Solenoid (CMS) experimental apparatus in both pp and heavy-ion collisions at root s(NN) = 2.76 TeV. The results are based on data collected in 2011 which correspond to an integrated luminosity of 150 pb-1 of PbPb and 231 nb(-1) of pp collisions. The yields measured in heavy-collisions are compared to those in pp scaled by the number of binary collisions via the nuclear modification factor, R-AA. The high-p(T) prompt J/psi show a suppression that does not vary with rapidity or p(T). The R-AA versus centrality calculated separately for Y(1S) and Y(2S), shows less suppression for the ground state. An upper limit for Y(3S) was also calculated. Combining all the quarkonia states RAA measured by CMS, and considering the binding energy of each state, an ordering of the suppression is observed, which establishes, experimentally, the validity of the sequential melting scenario in heavy-ion collisions. The non-prompt J/psi R-AA dependence with p(T) and rapidity was measured in fine bins of centrality. These represent the first detailed measurements, in heavy-ion collision, of the b-quark energy loss kinematic dependence.