A minimal quasiparticle approach for the QGP and its large-N c limits
Service de Physique Nucléaire et Subnucléaire, Université de Mons—UMONS, Place du Parc 20, 7000, Mons, Belgium
Revised: 20 September 2010
Published online: 19 November 2010
We propose a quasiparticle approach allowing to compute the equation of state of a generic gauge theory with gauge group SU(N c ) and quarks in an arbitrary representation. Our formalism relies on the thermal quasiparticle masses (quarks and gluons) computed from perturbative techniques, in which the standard two-loop running coupling constant is used. Our model is minimal in the sense that we do not allow any extra ansatz concerning the temperature-dependence of the running coupling. We first show that it is able to reproduce the most recent equations of state computed on the lattice for temperatures typically higher than 2T c . Well above T c indeed, an ideal-gas framework with thermal masses is expected to be relevant. Then we study the accuracy of various inequivalent large-N c limits concerning the description of the QCD results, as well as the equivalence between the QCD AS limit and the SUSY Yang–Mills theory.
© Springer-Verlag / Società Italiana di Fisica, 2010