Domain Wall Fermions in Quenched Lattice QCD

TL;DR

This paper investigates the chiral properties and perturbation theory validity of domain wall fermions in quenched lattice QCD at beta=6.0, finding small chiral symmetry breaking effects and consistent decay constants.

Contribution

It provides an analysis of chiral symmetry breaking and decay constants for domain wall fermions at finite fifth-dimensional extent in quenched lattice QCD.

Findings

Chiral symmetry breaking term is very small at Ns=10.

Decay constants from local and conserved currents agree well.

Evidence suggests the possible existence of a parity broken phase at finite Ns.

Abstract

We study the chiral properties and the validity of perturbation theory for domain wall fermions in quenched lattice QCD at beta=6.0. The explicit chiral symmetry breaking term in the axial Ward-Takahashi identity is found to be very small already at Ns=10, where Ns is the size of the fifth dimension, and its behavior seems consistent with an exponential decay in Ns within the limited range of Ns we explore. From the fact that the critical quark mass, at which the pion mass vanishes as in the case of the ordinary Wilson-type fermion, exists at finite Ns, we point out that this may be a signal of the parity broken phase and investigate the possible existence of such a phase in this model at finite Ns. The rho and pi meson decay constants obtained from the four-dimensional local currents with the one-loop renormalization factor show a good agreement with those obtained from the conserved currents.