A non-perturbative determination of Z_V and b_V for O(a) improved quenched and unquenched Wilson fermions

TL;DR

This paper non-perturbatively determines the renormalization constant Z_V and the quark mass improvement coefficient b_V for O(a) improved Wilson fermions by analyzing nucleon states and charge conservation, for both quenched and unquenched cases.

Contribution

It provides a non-perturbative calculation of Z_V and b_V for O(a) improved Wilson fermions, including unquenched configurations, enhancing accuracy in lattice QCD computations.

Findings

Determined Z_V and b_V non-perturbatively for quenched fermions.

Extended the determination to two-flavor unquenched fermions.

Confirmed charge conservation as a reliable method for renormalization.

Abstract

By considering the local vector current between nucleon states and imposing charge conservation we determine, for $O(a)$ improved Wilson fermions, its renormalisation constant and quark mass improvement coefficient. The computation is performed for both quenched and two flavour unquenched fermions.