FINITE-TEMPERATURE CHIRAL TRANSITIONS IN QCD WITH THE WILSON QUARK ACTION

We investigate the finite-temperature phase structure and the scaling of the chiral condensate in lattice QCD with two degenerate light quar ks, using a renormalization group improved gauge action and the Wilson quark action. We obtain a phase diagram which is consistent with that from the parity-flavor breaking scenario. The scaling relation for th e chiral condensate assuming the critical exponents and the scaling fu nction of the three dimensional O(4) model is remarkably satisfied for a wide range of parameters. This indicates that the chiral transition in two flavor QCD is of second order in the continuum limit.