Detailed measurements of charmonium suppression in PbPb collisions at $\sqrt{s_{NN}}=$ 2.76 TeV with CMS

CMS has measured the nuclear modification factors of prompt $J/\psi$ in PbPb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV. For prompt $J/\psi$ with relatively high $p_{\rm T}$ (6.5 $< p_{\rm T} <$ 30 GeV/c), a strong, centrality-dependent suppression is observed in PbPb collisions, compared to the yield in pp collisions scaled by the number of inelastic nucleon-nucleon collisions. During the 2011 data taking period the PbPb collision sample has been increased by a factor of twenty compared to 2010, which allows for more detailed charmonium measurements, e.g. mapping the transverse momentum and centrality dependence of the nuclear modification simultaneously. New results on charmonium suppression based on the full available 2011 data sample will be reported.