Mean Field Effect on J/psi Production in Heavy Ion Collisions

The mean field effect in quark-gluon plasma on J/\psi production in heavy ion collisions is perturbatively calculated in a transport approach. While the global nuclear modification factor R_{AA} is not sensitive to the mean field, the reduced threshold for J/\psi regeneration leads to a significant enhancement of R_{AA} at low transverse momentum at RHIC and LHC energies.