Renormalization constants for one-derivative fermion operators in twisted mass QCD

TL;DR

This paper computes renormalization constants for one-derivative fermion operators in twisted mass QCD using both perturbative and non-perturbative methods, providing results across various lattice spacings and pion masses.

Contribution

It offers a comprehensive analysis of renormalization constants in twisted mass QCD, combining perturbative and non-perturbative approaches with detailed scale evolution and scheme conversion.

Findings

Renormalization constants are computed for multiple lattice spacings.

O(a^2) lattice artifacts are subtracted perturbatively.

Results are translated to MS-bar scheme at 2 GeV.

Abstract

We present perturbative and non-perturbative results on the renormalization constants of the local and one-derivative vector and axial vector operators. Non-perturbative results are obtained using the twistedmassWilson fermion formulation employing two degenerate dynamical quarks and the tree-level Symanzik improved gluon action for pion masses in the range of about 450-260 MeV and at there values of the lattice spacing, namely 0.055 fm, 0.070 fm and 0.089 fm. Subtraction of O(a^2) terms is carried out by performing the perturbative evaluation of these operators at 1- loop and up to O(a^2). The renormalization conditions are defined in the RI'-MOM scheme, for both perturbative and non-perturbative results. The Z-factors, obtained for different values of the renormalization scale, are evolved perturbatively to a reference scale set by the inverse of the lattice spacing. In addition, they are translated to MS-bar at 2 GeV using 3-loop perturbative results for the conversion factors.