Speaker
Description
The Psi prime (Psi(2S)) meson yield in PbPb collisions is of particular interest when compared to the J/psi meson. A variety of effects modify the charmonium production in PbPb collisions with respect to pp collisions, including melting in the quark gluon plasma and statistical recombination, which can have a different impact on the J/psi and the Psi(2S) mesons. Using pp and PbPb data at sqrt(s_NN) = 2.76 TeV, the CMS Collaboration has previously reported that the Psi(2S) meson is more suppressed than the J/psi at midrapidity and high pt (|y|<1.6. pt>6.5), but a hint of less suppression at forward rapidity and intermediate pt (1.6<|y|<2.4, pt>3). New results on the relative J/psi and Psi(2S) modification, based on the pp and PbPb data recently collected at sqrt(s_NN) = 5.02 TeV by the CMS Collaboration, will be reported.
