Cold and Hot Nuclear Matter Effects on Charmonium Production in p+Pb Collisions at LHC Energy

TL;DR

This paper investigates how cold and hot nuclear matter influence charmonium production in proton-lead collisions at LHC energies, using a transport model to interpret experimental data and predict particle behavior.

Contribution

It introduces a transport approach to distinguish cold and hot medium effects on charmonium states, successfully explaining forward rapidity data and predicting $ ext{p}_T$ broadening.

Findings

Cold medium effects explain $J/\psi$ and $\psi'$ yields at forward rapidity.

Hot medium effects account for excited $c\bar c$ states at forward rapidity.

Predicted larger $\psi'$ $p_T$ broadening compared to $J/\psi$.

Abstract

We study cold and hot nuclear matter effects on charmonium production in p+Pb collisions at $\sqrt{s_\text{NN}}=5.02$ TeV in a transport approach. At the forward rapidity, the cold medium effect on all the $c\bar c$ states and the hot medium effect on the excited $c\bar c$ states only can explain well the $J/\psi$ and $\psi'$ yield and transverse momentum distribution measured by the ALICE collaboration, and we predict a significantly larger $\psi'$ $p_\text{T}$ broadening in comparison with $J/\psi$. However, we can not reproduce the $J/\psi$ and $\psi'$ data at the backward rapidity with reasonable cold and hot medium effects.