Nuclear suppression of J/Psi: from RHIC to the LHC

TL;DR

This paper presents a parameter-free dipole model for J/Psi suppression in pA and AA collisions, successfully matching RHIC data and predicting effects at the LHC, with implications for understanding dense medium interactions.

Contribution

It introduces a refined, parameter-free dipole model accounting for initial state interactions and saturation effects, extending analysis from pA to AA collisions and predicting LHC suppression.

Findings

Good agreement with PHENIX pA data

Determined transport coefficient at RHIC energies

Predicted J/Psi suppression at LHC energies

Abstract

A parameter-free calculation for J/Psi suppression in pA collisions, based on the dipole description, is confronted with the new data from the PHENIX experiment. Achieving good agreement, we employed this model predicting the contribution of initial state interactions (ISI) to J/Psi suppression in AA collisions. Such a transition from pA to AA is not straightforward, since involves specific effects of double color filtering and boosting of the saturation scale. Relying on this refined ISI contribution, we updated the previous analysis of RHIC data on J/Psi production in Cu-Cu and Au-Au collisions at \sqrt{s}=200 GeV, and determined the transport coefficient of the created dense medium at q_0=0.6 GeV^2/fm. Nuclear effects for J/Psi production at the LHC are predicted using the transport coefficient q_0=0.8 GeV^2/fm, extracted from data on suppression of high-p_T hadrons in central lead-lead collisions at \sqrt{s}=2.76 TeV. Our analysis covers only direct J/Psi production, while data may also include the feed-down from decay of heavier states and B-mesons.