Non-zero elliptic flow has been observed for the J/\(\psi\) meson, providing further evidence that the charm quarks are thermalised and participate in the collective flow of the plasma, as expected in a recombination scenario. The elliptic flow at higher transverse momenta, where a significant contribution from primordial J/\(\psi\) is expected, is not well described by model calculations and currently not well understood.
The new Pb-Pb data will allow detailed investigations of the flow pattern as a function of collision centrality and transverse momentum, which may give additional information on the interactions of charm quarks with the plasma and the balance between different J/\(\psi\) production mechanisms.