Quark deconfinement and meson properties at finite temperature

Abstract

A simple confining separable interaction Ansatz for the rainbow-ladder truncated QCD Dyson-Schwinger equations is used to study quark deconfinement and meson states at finite temperature. The model is fixed at T=0 to implement quark confinement while preserving the Goldstone mechanism for the $\pi$. Within the Matsubara formalism, a very slow temperature dependence is found for the $\pi$ and $\rho$ meson masses $M_H(T)$ until near the deconfinement temperature $T_c=143$ MeV. Related to rapid decrease of the dynamically-generated quark mass function for $T>T_c$, this model produces $\pi$ and $\rho$ masses that rise significantly and are better interpreted as spatial screening masses. The $T$-dependent screening mass defect $\Delta M_H = 2\pi T-M_H(T)$ is compared to results of lattice gauge theory simulations and also to those of an infrared dominant analytic model.