Rapidity Dependence of $J/\psi$ Production at RHIC and LHC

TL;DR

This paper models the rapidity dependence of $J/$ production in heavy ion collisions at RHIC and LHC using a 3D transport equation, explaining observed suppression patterns through production mechanisms.

Contribution

It introduces a comprehensive 3D transport model that accounts for initial production and regeneration, clarifying rapidity-dependent suppression phenomena at RHIC and LHC.

Findings

Stronger $J/\psi$ suppression at forward rapidity at RHIC explained by production competition.

At LHC, regeneration dominates the rapidity dependence of $J/\psi$ production.

The model successfully reproduces experimental suppression patterns.

Abstract

The motion of charmonium in heavy ion collisions is described by a three dimensional transport equation with initial production and continuous regeneration in hot medium. The observation of apparently stronger $J/\psi$ suppression at forward rapidity compared to that at midrapidity, so called $J/\psi$ puzzle at RHIC, can well be explained by the competition between the two production mechanisms. At LHC, however, the rapidity dependence of the $J/\psi$ production is dominated by the regeneration process.