We first review the cold and hot nuclear matter effects on quarkonium production in high energy collisions, then discuss three kinds of models to describe the quarkonium suppression and regeneration: the sequential dissociation, the statistical production and the transport approach, and finally make comparisons between the models and the experimental data from heavy ion collisions at SPS, RHIC and LHC energies.
Towards understanding the $\phi$ meson in nuclear matter with finite momentum
