Charmonium Production, Statistical Hadronization and the QCD Phase Boundary

Peter Braun-Munzinger

ExtreMe Matter Institute EMMI and Research Division
GSI, Darmstadt, Germany

We argue that, at collider energies, charmonium production in nucleus-nucleus collisions takes place after the formation of the quark-gluon plasma.  This, coupled with the copious production of charm quarks in each collision, leads to a characteristic centrality dependence of the corresponding nuclear modification factor if the charm quarks are deconfined in the hot and dense fireball.  We analyze data from RHIC  and from the LHC in terms of the statistical hadronization model [1] and describe the emerging physical picture.

[1] P. Braun-Munzinger and J. Stachel, Landolt review volume on relativistic nucleus-nucleus collisions, R. Stock, editor, Springer 2009, arXiv:0901.2500 [nucl-th]