Charmonium at finite temperature

TL;DR

This study investigates how charmonium states behave at high temperatures using lattice QCD, revealing that some ground states survive deconfinement while others dissociate early, informing understanding of quark-gluon plasma.

Contribution

It provides the first lattice QCD analysis of charmonium spectral functions at finite temperature with quenched approximation and isotropic lattices at multiple lattice spacings.

Findings

Ground state charmonia survive above deconfinement up to 1.5Tc.

P-wave charmonia dissociate at around 1.12Tc.

Medium modifications observed in spectral functions.

Abstract

We study charmoinum correlators and spectral functions at finite temperature within the quenched approximation using isotropic lattices with lattice spacing a^-1=4.86 GeV and 9.72 GeV. Although we observe some medium modifications of the ground state charmonium spectral function above deconfinement, we find that ground state charmonia (J/psi and eta_c) exist in the deconfined phase at least up to temperatures as high as 1.5Tc. P-wave charmonia (chi_c) on the other hand are dissociated already at 1.12Tc.