Testing charm quark thermalisation within the Statistical Hadronisation Model

TL;DR

This paper extends the statistical hadronisation model to analyze J/ψ transverse momentum distributions in Pb-Pb collisions, testing charm quark thermalisation in the quark-gluon plasma using hydrodynamical input and experimental data.

Contribution

It introduces an extension of the statistical hadronisation model incorporating hydrodynamical inputs to study charm quark thermalisation in heavy-ion collisions.

Findings

J/ψ transverse momentum spectra are consistent with charm quark thermalisation.

The model successfully describes experimental data at different collision energies.

Evidence supports (re-)generation as a key production mechanism for J/ψ at low transverse momentum.

Abstract

A wealth of data on charmonium production in Pb-Pb collisions from the LHC experiments has provided strong evidence for (re-)generation as a dominant production mechanism at low transverse momentum. We present an important extension of the statistical hadronisation model to describe $\rm{J}/\psi$ transverse momentum distributions based on input parameters from hydrodynamical simulations. Comparison to the data allows the testing of the degree of thermalisation of charm quarks in the quark-gluon plasma. To this end we will report analyses of the $\rm{J}/\psi$ transverse momentum spectra in Pb-Pb collisions at $\sqrt{s_{\rm NN}} = 2.76$ and $5.02$ TeV.