HQET Flavor Currents Using Automated Lattice Perturbation Theory

TL;DR

This paper uses automated lattice perturbation theory to evaluate candidate matching observables for heavy-light flavor currents in HQET, aiming to improve the precision of theoretical predictions relevant for particle physics phenomenology.

Contribution

It extends HQET matching calculations to include additional current components using automated lattice perturbation theory, testing observables for future non-perturbative studies.

Findings

Identified candidate observables for vector and axial vector currents.

Performed one-loop lattice perturbation theory calculations.

Provided insights for future non-perturbative matching efforts.

Abstract

Matrix elements of heavy-light flavor currents play an important role in modern particle physics and precise theory predictions are of interest for phenomenology. Heavy Quark Effective Theory (HQET) is a valuable tool to obtain such predictions. In the HQET matching program of the ALPHA collaboration presently only the temporal component of the axial vector current is included. Extending the matching to the temporal component of the vector current and the spatial components of the axial vector current thus seems desirable. Here we present a recent one-loop study in lattice perturbation theory to test two candidate matching observables for these currents for their quality to guide future non-perturbative investigations.