Statistical approach of the quark-gluon plasma

Nowadays, Quark-Gluon Plasma (QGP) is a very active research field both theoretically and
experimentally. QGP is a QCD state of matter obtained at large enough temperatures and/or
baryonic densities and characterized by a deconfinement of quarks and gluons (i.e. quarks and
gluons can move quasi freely). We propose here a quasiparticle approach to describe QGP.
We use an ideal-gas framework in which quark and gluon masses depend on temperature.
Our model is minimal in the sense that we use thermal quasiparticle masses (quarks and
gluons) computed from perturbative techniques with standard two-loop running coupling
constant and we do not allow any extra ansatz concerning the temperature-dependence of the
running coupling. We show that it is able to reproduce the most recent equations of state
computed on the lattice for temperatures typically higher than 2 times the critical temperature
(Tc). This approach is expected to be relevant well above Tc, in temperature range in which is
reasonable to neglect interactions between quasiparticles. We also compute this equation of
state for a generic gauge theory with gauge group SU(Nc) in order to study the accuracy of
various inequivalent large-Nc limits.