Thermodynamics of the Glueball Resonance Gas

TL;DR

This paper models the thermodynamics of a glueball gas using the Glueball Resonance Gas approach, successfully describing Yang-Mills sector properties below the critical temperature and analyzing the impact of heavier and interacting glueballs.

Contribution

It introduces the Glueball Resonance Gas model incorporating lattice glueball states and assesses the effects of heavier and interacting glueballs on thermodynamic properties.

Findings

GRG describes Yang-Mills thermodynamics below T_c

Heavier glueballs add minimal correction

Interactions between glueballs are negligible

Abstract

We study the thermodynamic properties -- pressure, entropy and trace anomaly -- of a gas of glueballs that includes the glueball states obtained by various lattice simulations. We show that this model, called Glueball Resonance Gas (GRG) approach, describes well the thermal properties of the Yang-Mills sector of QCD below the critical temperature $T_c$, provided that $T_c$ is properly matched to the corresponding determination of the glueball masses, obtaining $T_c \sim 320 \pm 20$ MeV. The inclusion into the GRG of heavier glueballs not yet seen on the lattice, assuming that glueballs follow Regge trajectories as quark-antiquark states do, leads only to a small correction. We consider the contribution to the pressure of the interactions between scalar-scalar and tensor-tensor glueballs, which turn out to be also negligible.