Renormalization of bilinear quark operators for the chirally improved lattice Dirac operator

TL;DR

This paper non-perturbatively computes renormalization constants for fermionic bilinears using chirally improved lattice fermions in quenched QCD, addressing finite size effects and scheme conversions.

Contribution

It provides the first non-perturbative renormalization constants for chirally improved lattice fermions in multiple schemes, including corrections to previous perturbative coefficients.

Findings

Renormalization constants are computed in RI', MSbar, and RGI schemes.

Finite size effects and Gribov copies influence the results.

A correction to the perturbative coefficient slightly alters scheme conversion factors.

Abstract

We compute non-perturbative renormalization constants of fermionic bilinears for the chirally improved lattice fermions in the quenched approximation of QCD. We address finite size effects and the influence of Gribov copies. Our results are presented in the RI' and MSbar schemes as well as in RGI form and we discuss relations between the renormalization constants implied by chiral symmetry. After publication we corrected the numerator of the first coefficient of \alpha_s^3 in (24) from 3696847 to 3890527, which yields a 0.2% higher value of the conversion coefficient at \mu=2 GeV.