One loop matching coefficients for a variant overlap action--and some of its simpler relatives

TL;DR

This paper computes one-loop matching coefficients between continuum QCD and lattice QCD with overlap fermions, focusing on a variant with fat link gauge connections, and compares results across different fermion discretizations.

Contribution

It provides the first one-loop perturbative calculations for a variant overlap fermion action with fat links, including various operators and renormalization factors.

Findings

Matching coefficients for overlap and other fermion actions are calculated.

Results include additive mass renormalization and current renormalizations.

The scale for the running coupling is determined using the Lepage-Mackenzie scheme.

Abstract

I present one-loop perturbative calculations of matching coefficients between matrix elements in continuum regulated QCD and lattice QCD with overlap fermions, with emphasis a recently-proposed variant discretization of the overlap. These fermions have extended (``fat link'') gauge connections. The scale for evaluation of the running coupling constant (in the context of the Lepage-Mackenzie fixing scheme) is also given. A variety of results (for additive mass renormalization, local currents, and some non-penguin four-fermion operators) for naive, Wilson, clover, and overlap actions are shown.