Quarkonia production in small and large systems measured by ATLAS

The experimentally observed dissociation and regeneration of bound quarkonium 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, or other, new suppression mechanisms. 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 quarkonia states, as well as their separation into prompt and non-prompt components, provide further opportunities to study the dynamics of heavy parton energy loss in these large systems. In addition, quarkonium production rates, and their excited to ground states ratios, in small, asymmetric systems are an interesting probe of cold nuclear matter effects. In this talk, the latest ATLAS results on quarkonia production will be presented, including new, differential measurements of charmonium suppression and azimuthal modulation in lead-lead collisions, and a broad measurement of the production of five quarkonium states, differential in quarkonium kinematics, in proton-lead collisions.