ψ(2S) production and nuclear modification factor in nucleus–nucleus collisions with ALICE

Charmonium production is sensitive to deconfinement in nucleusnucleus collisions. The via regeneration within the QGP or at phase boundary has been identified as an important ingredient for description of centrality and transverse momentum dependence ( p T ) J /ψ nuclear modification factor R AA LHC. ψ(2S) relative one possible discriminator between two different scenarios. At there so far no significant observation central nucleus-nucleus collisions low- , where expected play role. combined Run 2 data set ALICE allows extract a signal this kinematic region forward rapidity, dimuon decay channel. In contribution, we present first time results on ψ(2S)-to-J/ψ single ratio double (to pp collisions) well factor, Pb-Pb √S NN = 5.02 TeV. ψ(2S)-to- are calculated using new proton-proton reference with improved precision. Results compared model calculations.