The quark propagator at finite temperature

Abstract

We study the quark propagator at finite temperature on euclidean lattices in the Landau gauge, and compare the results to an O(g²) lattice weak coupling calculation. The screening mass obtained from spatial correlation functions in the chiral symmetric phase is close to the Matsubara frequency. The temporal correlation functions yield a much smaller screening mass, which approaches the perturbative result, m_eff²=g²T²/6, for T≳1.75 T_c. Deviations from the perturbative behaviour are seen for T_c≤T≤1.75 T_c. For T≤T_c, the screening masses from both spatial and temporal correlation functions are large and close to half the mass of the ϱ-meson. Dispersion relations do not show any significant deviations from free particle behaviour.