Two-loop evaluation of large Wilson loops with overlap fermions: the b-quark mass shift, and the quark-antiquark potential

TL;DR

This paper performs a two-loop perturbative calculation of Wilson loops with overlap fermions to determine the b-quark mass shift and the quark-antiquark potential, comparing results with clover action and existing literature.

Contribution

It provides the first two-loop fermionic contribution calculations for Wilson loops using overlap fermions, including the b-quark mass shift and static potential evaluation.

Findings

Calculated fermionic contributions to Wilson loops at two loops

Determined the b-quark mass shift from large R,T limits

Evaluated the static quark-antiquark potential perturbatively

Abstract

We compute, to two loops in pertubation theory, the fermionic contribution to rectangular RxT Wilson loops, for different values of R and T. We use the overlap fermionic action. We also employ the clover action, for comparison with existing results in the literature. In the limit R, T -> Infinity our results lead to the shift in the b-quark mass. We also evaluate the perturbative static potential as T -> Infinity.