Effective model for hot gluodynamics - art. no. 045206

We consider an effective Lagrangian containing contributions from glueball and gluon degrees of freedom with a scale-invariant coupling between the tw o. The thermodynamic potential is calculated taking into account thermal fl uctuations of both fields. The glueball mean field dominates at low tempera ture, while the high temperature phase is governed by low-mass gluonlike ex citations. The model shows some similarities to the lattice results in the pure glue sector of QCD. In particular, it exhibits a strong first order ph ase transition at a critical temperature of approximately 265 MeV when reas onable parameters are taken.