Glueballs and statistical mechanics of the gluon plasma

TL;DR

This paper models the gluon plasma as a gas of massive gluons and glueballs, using lattice data to determine temperature-dependent masses, and suggests the plasma is rich in glueballs near the critical temperature.

Contribution

It introduces a thermodynamically consistent quasiparticle model with temperature-dependent gluon masses and interprets the gluon plasma as a glueball-rich medium near the critical temperature.

Findings

Gluon mass derived from lattice QCD matches across formalisms.

Gluon plasma may be dominated by glueballs below 1.13 T_c.

Potential detection of glueballs in future quark-gluon plasma experiments.

Abstract

We study a pure gluon plasma in the context of quasiparticle models, where the plasma is considered as an ideal gas of massive bosons. In order to reproduce SU(3) gauge field lattice data within such a framework, we review briefly the necessity to use a temperature-dependent gluon mass which accounts for color interactions between the gluons near $T_{\text{c}}$ and agrees with perturbative QCD at large temperatures. Consequently, we discuss the thermodynamics of systems with temperature-dependent Hamiltonians and clarify the situation about the possible solutions proposed in the literature to treat consistently those systems. We then focus our attention to two possible formulations which are thermodynamically consistent and we extract the gluon mass from the equation of state obtained in SU(3) lattice QCD. We find that the thermal gluon mass is similar in both statistical formalisms. Finally, an interpretation of the gluon plasma as an ideal gas made of glueballs and gluons is also presented. The glueball mass is consistently computed within a relativistic formalism using a potential obtained from lattice QCD. We find that the gluon plasma might be a glueball-rich medium for $T\lesssim 1.13 T_{\text{c}}$ and suggest that glueballs could be detected in future experiments dedicated to the quark-gluon plasma.