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

Abstract

We compute, to two loops in perturbation theory, the fermionic contribution to rectangular R × T 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 → ∞ our results lead to the shift in the static quark energy, which can be used to determine the b-quark mass. We also evaluate the perturbative static potential as T → ∞. © 2008 Elsevier B.V. All rights reserved.