Charmonia and open charm production in heavy ion collisions

The production of heavy flavours in heavy ion collisions has been of great interest since the prediction of Matsui and Satz regarding quarkonium suppression in the quark gluon plasma due to color screening mechanisms. The NA50 collaboration has produced the first charmonia measurements in heavy ion collisions which show evidence for strong and anomalous suppressions in central Pb-Pb collisions. For the suppression of bound state quark-antiquark pairs to be a plasma signature, the production of these quarks inside the cold nucleus should first be well known. Differences in the relative yield of heavy flavour between nucleon-nucleon an nucleon-nucleus collisions probes cold nuclear matter effects such as the modifications of the gluon distribution functions or parton energy loss. The gluon-gluon fusion represents the dominant mechanism for the production of quarkonia studied by the heavy ion experiments. The purpose of this presentation is to highlight the latest results from the CERN-SPS and Fermilab fixed target experiments and the first results from the heavy ion collider RHIC.