Equation of state of a quark-meson mixture in the improved Polyakov–Nambu–Jona-Lasinio model at finite chemical potential
Résumé
We study the equation of state of QCD using an improved version of the three-flavor Polyakov–Nambu–Jona-Lasinio model beyond the mean-field approximation. It incorporates the effects of unquenched quarks into the Polyakov-loop effective potential, as well as mesonic contributions to the grand-canonical potential. We study in full detail the calculation of the thermodynamical potential in this approach and compare the resulting pressure and entropy density with the most-recent lattice-QCD calculations at zero baryochemical potential. Finally, we present some exploratory results at finite chemical potential which include the phase diagram of the model, the quark and meson masses, and finally, the thermodynamical pressure.
Mots clés
potential: chemical
potential: thermodynamical
quantum chromodynamics: equation of state
entropy: density
meson: mass
mean field approximation
lattice field theory
effective potential
Polyakov loop
quark: mass
critical phenomena: quark hadron
gap equation
effective Lagrangian
transition: chiral
Jona-Lasinio-Nambu model
temperature: low
quark hadron
numerical calculations