Anti-shadowing Effect on Charmonium Production at a Fixed-target Experiment Using LHC Beams

TL;DR

This paper studies how anti-shadowing influences charmonium production in Pb+Pb collisions at LHC fixed-target energies, revealing rapidity-dependent suppression effects on J/psi yields and transverse momentum.

Contribution

It introduces a transport model analysis of cold and hot nuclear matter effects, highlighting the role of anti-shadowing on charmonium suppression at fixed-target energies.

Findings

Yield suppression varies with rapidity due to shadowing effects.

Anti-shadowing impacts nuclear modification factors $R_{AA}$ and $r_{AA}$.

Suppression is more pronounced at less forward rapidity.

Abstract

We investigate charmonium production in Pb+Pb collisions at LHC beam energy $E_{\text {lab}}$=2.76 A TeV at fixed-target experiment ($\sqrt {s_{\text{NN}}}$=72 GeV). In the frame of a transport approach including cold and hot nuclear matter effects on charmonium evolution, we focus on the anti-shadowing effect on the nuclear modification factors $R_{AA}$ and $r_{AA}$ for the $J/\psi$ yield and transverse momentum. The yield is more suppressed at less forward rapidity ($y_\text{lab}\simeq$2) than that at very forward rapidity ($y_\text{lab}\simeq$4) due to the shadowing and anti-shadowing in different rapidity bins.