QCD phase transition with two flavors of Wilson quarks using a RG improved action

TL;DR

This study investigates the finite temperature QCD phase transition with two flavors of Wilson quarks on the lattice, demonstrating that a renormalization group improved gauge action resolves previous irregular behaviors and reveals a smooth transition.

Contribution

The paper introduces an RG-improved gauge action for lattice QCD with Wilson quarks, addressing issues seen with standard actions at finite temperature.

Findings

Improved action removes strange behaviors seen with standard actions.

Transition is continuous in the chiral limit and smoothens with increasing quark mass.

Results suggest a smoother crossover transition with the improved action.

Abstract

The finite temperature QCD phase transition is studied on the lattice with degenerate two flavors of Wilson quarks. Motivated by reported strange behaviors with the standard action on lattices with the temporal extention $N_t=4$ and 6, a renormalization group improved gauge action is applied. On an $N_t=4$ lattice, the strange behaviors observed with the standard action are removed with our improved action. The finite temperature transition is continuous in the chiral limit and it becomes quite smooth in all observables we studied when we increase the quark mass by increasing $\beta$ along the crossover line.