THE QUARK PROPAGATOR AT FINITE TEMPERATURE

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(eff)2 = g2T2/6, for T greater than or similar to 1.75 T(c). Deviations from the perturbative behaviour are seen for T(c) less-than-or-equal-to T less-than-or-equal-to 1.75 T(c). For T less-than-or-equal-to T(c), the screening masses from both spatial and temporal correlation functions are large and close to half the mass of the rho-meson. Dispersion relations do not show any significant deviations from free particle behaviour.