The Nf=2 residual mass in Perturbative Lattice-HQET for an improved determination of the (MS bar) b-quark mass

TL;DR

This paper calculates the residual mass in Nf=2 lattice HQET to order alpha^3 using Numerical Stochastic Perturbation Theory, aiming to refine the b-quark mass determination in the MSbar scheme.

Contribution

It provides a high-order perturbative calculation of the residual mass in lattice HQET, enhancing the precision of b-quark mass extraction from lattice data.

Findings

Computed the residual mass coefficient to order alpha^3

Improved the accuracy of the b-quark mass determination

Demonstrated the effectiveness of Numerical Stochastic Perturbation Theory

Abstract

We determine to order alpha^3 the so-called residual mass in the lattice regularisation of the Heavy Quark Effective Theory for Nf=2. Our (gauge-invariant) strategy makes use of Numerical Stochastic Perturbation Theory to compute the static interquark potential where the above mentioned mass term appears as an additive contribution. We discuss how the new coefficient we compute in the expansion of the residual mass can improve the determination of the (MS bar) mass of the b-quark from lattice simulations of the Heavy Quark Effective Theory.