Non-perturbative determination of heavy quark action coefficients

TL;DR

This paper introduces a non-perturbative method to determine heavy quark action coefficients by matching finite-volume gauge-fixed propagators and vertices with relativistic theory, using perturbative or step-scaling approaches.

Contribution

It presents a novel non-perturbative approach for tuning heavy quark action coefficients via off-shell amplitude matching in finite volume.

Findings

Tree-level matching results are provided.

Non-perturbative off-shell amplitudes are computed.

Method enables precise heavy quark simulations.

Abstract

We propose to determine the coefficients in the Fermilab heavy quark action by matching the finite-volume, off-shell, gauge-fixed propagator and vertex functions with those determined in the exact, relativistic theory. The matching relativistic amplitudes may be determined either from short-distance perturbation theory or from finite-volume step-scaling recursion. Tree-level matching and non-perturbative off-shell amplitudes are presented.