Quarkonium production in nuclear collisions

Abstract

In these proceedings, an overview of recent quarkonium measurements in nuclear collisions carried out at both RHIC and LHC is presented. In p+p collisions, despite theoretical progresses made in understanding the production mechanisms for quarkonia, a complete picture is still yet to be achieved. In p+A collisions where measurements are done to quantify the cold nuclear matter effects, significant suppression of quarkonium production is observed for low transverse momentum region at both forward-and mid-rapidities. Furthermore, results from A+A collisions show the interplay of dissociation and regeneration contributions for charmonium at different collision energies, while a correspondence between the suppression level and the binding energy is observed for bottomonium family. Comparisons to experimental data provide stringent tests to model calculations, and help constrain the temperature of the deconfined medium created in heavy-ion collisions.

Melting of heavy vector mesons and quasinormal modes in a finite density plasma from holography

“…As can be seen, u 2 1 does not depend on the chemical potential, while u 2 2 is always negative for µ > 0. Meanwhile, u 2 3 > 1 for µ > 0, while it becomes u 2 3 = 1 for µ = √ 6, and u 2 3 < 1 for µ > √ 6. For that reason we restrict our numerical analysis to the region where µ ≤ √ 6.…”

“…In this plasma, light quarks and gluons interact strongly but are not confined inside hadrons. It is believed that one can use heavy mesons as probes in order to extract relevant information of the medium in such extreme conditions [1][2][3]. The idea is that, in contrast to hadrons made of the light quarks: u (up), d (down), and s (strange), that dissociate at the critical temperature [4] when the plasma is formed, heavy mesons, made of c (charm) or b (bottom) quarks survive at higher temperatures.…”