Resolving the J/ψ RHIC puzzles at the LHC

Experiments with gold–gold collisions at the RHIC have revealed (i) stronger suppression of charmonium production at forward rapidity than at mid-rapidity and (ii) the similarity between the suppression degrees at RHIC and SPS energies. To describe these findings we employ the model that includes nuclear shadowing effects, calculated within the Glauber–Gribov theory, rapidity-dependent absorptive mechanism, caused by energy–momentum conservation, and dissociation and recombination of the charmonium due to interaction with co-moving matter. The free parameters of the model are tuned and fixed by comparison with experimental data at lower energies. A good agreement with the RHIC results concerning the rapidity and centrality distributions is obtained for both heavy Au+Au and light Cu+Cu colliding systems. For pA and A+A collisions at the LHC the model predicts stronger suppression of the charmonium and bottomonium yields in stark contrast to thermal model predictions.