Open and hidden charm in proton-nucleus and heavy-ion collisions

Understand

We review the collectivity and the suppression pattern of charmed mesons - produced in proton-nucleus and nucleus-nucleus collisions at SPS (158 AGeV) and RHIC energies (21 ATeV) - in comparison to dynamical and thermal models.

• In particular, we examine the charmonium `melting' and the `comover dissociation' scenarios - implemented in a microscopic transport approach - in comparison to the available data from the SPS and RHIC.
• The analysis shows that the dynamics of c, c-bar quarks at RHIC are dominated by partonic or `pre-hadronic' interactions in the strongly coupled plasma stage.
• Both the `charmonium melting' and the hadronic `comover absorption and recreation model' are found, however, to be compatible with the experimental observation at SPS energies; the experimental ratio of Psi'/J/Psi versus centrality clearly favors the `hadronic comover' scenario.