Non-Perturbative Renormalisation of Composite Operators

TL;DR

This paper presents a non-perturbative method to accurately determine renormalisation constants of composite operators in lattice QCD using Chiral Ward identities, avoiding lattice perturbation theory.

Contribution

It introduces a new approach for computing renormalisation constants of composite operators non-perturbatively with high precision.

Findings

Renormalisation constants can be determined within a few percent accuracy.

The method does not rely on lattice perturbation theory.

18 gluon configurations suffice for high-precision results.

Abstract

It is shown that the renormalisation constants of two quark operators can be accurately determined (to a precision of a few per-cent using 18 gluon configurations) using Chiral Ward identities. A method for computing renormalisation constants of generic composite operators without the use of lattice perturbation theory is proposed.