Stout-link smearing in lattice fermion actions

TL;DR

This study investigates how stout-link smearing affects the quark propagator functions in lattice QCD, revealing minor impacts on wave-function renormalization and mass functions for light quarks, but significant effects for heavy quarks.

Contribution

It provides a detailed analysis of the influence of stout-link smearing on the quark propagator in lattice QCD, highlighting the dependence on quark mass and smearing levels.

Findings

Wave-function renormalization is slightly affected by smearing.

Mass function shows minimal change for light quarks with smearing.

Heavy quark mass results are strongly dependent on smearing sweeps.

Abstract

The properties of the momentum space quark propagator in Landau gauge are studied for the overlap quark action in quenched lattice QCD. Numerical calculations are performed over four ensembles of gauge configurations, where three are smeared using either 1, 3, or 6 sweeps of stout-link smearing. We calculate the non-perturbative wave function renormalization function $Z(p)$ and the non-perturbative mass function $M(p)$ for a variety of bare quark masses. We find that the wave-function renormalization function is slightly sensitive to the number of stout-link smearing sweeps. For the mass function we find the effect of the stout-link smearing algorithm to be small for moderate to light bare quark masses. For a heavy bare quark mass we find a strong dependence on the number of smearing sweeps.