Speaker
Description
The experimentally observed dissociation and regeneration of bound charmonium states in heavy-ion collisions provide a powerful tool to probe the dynamics of the hot, dense plasma. These measurements are sensitive to the effects of color screening, color recombination, and possibly to other, new phenomena affecting dynamics of heavy quarks in the QCD medium. In the large-statistics Run 2 lead-lead and proton-lead collision data, these phenomena can be probed with unprecedented precision. Measurements of the ground and excited charmonium states, as well as their separation into prompt and non-prompt components, provide further opportunities to study the dynamics of heavy quark energy loss. In addition, charmonium production rates, and excited to ground states ratios, in small systems are a valuable probe of cold nuclear matter effects. In this talk, the latest ATLAS results on charmonia production will be presented, including new, differential measurements of charmonium suppression and azimuthal anisotropy in lead-lead and proton-lead collisions.
