An investigation into the Fermilab approach to heavy quarks on the lattice

TL;DR

This paper evaluates a non-perturbatively fixed asymmetric fermion action for heavy quarks on the lattice, comparing its spectral and matrix element results with symmetric actions, supporting the Fermilab interpretation that heavy quark physics depends mainly on kinetic mass.

Contribution

It introduces a non-perturbatively tuned asymmetric fermion action and demonstrates its effectiveness in reproducing heavy quark physics consistent with the Fermilab approach.

Findings

Spectra and matrix elements agree with symmetric action results

Relativistic dispersion relation is restored

Supports the Fermilab interpretation of heavy quark physics

Abstract

We use a space-time asymmetric O(a) improved fermion action and fix the asymmetry non-perturbatively to restore the relativistic dispersion relation. We compute spectra and matrix elements of quarkonia and heavy-light mesons and compare with results obtained using a symmetric action with the Fermilab interpretation i.e. that the physics of heavy lattice quarks depends solely on their kinetic mass. We provide additional evidence to support this.