Nonperturbative quark mass and coupling renormalization in two flavor QCD.

Abstract

Nonperturbative bare quark mass and coupling renormalization is studied for two flavor quantum chromodynamics (QCD). In particular, the β function for the case of Kogut-Susskind quarks is determined over the parameter space of existing lattice (spectrum) simulations from the existing spectrum data. This β function is combined with a series of finite temperature lattice simulations (N(t) = 4) to calculate the interaction measure, ε-3p, which together with the pressure yields the thermal equation of state. A method of computing the asymmetry, or Karsch, coefficients, is also given. These coefficients give the parameter renormalizations for anisotropic lattices. However, for the three points in parameter space that we studied (one using Wilson fermions and two using Kogut-Susskind fermions), a clear determination of the asymmetry coefficients could not be made because of the remarkable fact that ratios of masses measured in different directions on lattices with anisotropic couplings were Euclidean invariant.