Chiral restoration of the momentum space quark propagator through Dirac low-mode truncation

TL;DR

This study investigates how removing low-lying Dirac eigenmodes affects the quark propagator in lattice QCD, revealing a gradual loss of dynamical mass and suppression of wave-function renormalization at low momenta, indicating chiral symmetry restoration.

Contribution

It provides a detailed lattice QCD analysis of chiral symmetry restoration through Dirac low-mode truncation and employs improved techniques to reduce discretization artifacts.

Findings

Dynamically generated mass dissolves with low-mode removal

Strong suppression of wave-function renormalization at small momenta

Chiral symmetry tends to restore gradually with mode truncation

Abstract

We calculate the chirally improved (CI) Landau gauge quark propagator in two flavor lattice Quantum Chromodynamics and study thereon the effects of Dirac low-mode removal. The application of tree-level improvement of the propagator and tree-level correction of the lattice dressing functions removes the leading discretization artifacts. We find the dynamically generated mass in the infrared domain of the mass function to dissolve continuously with the reduction level and furthermore we observe strong suppression of the wave-function renormalization function for small momenta.