Renormalization constants for 2-twist operators in twisted mass QCD

Abstract

Perturbative and non-perturbative results on the renormalization constants of the fermion field and the twist-2 fermion bilinears are presented with emphasis on the non-perturbative evaluation of the one-derivative twist-2 vector and axial vector operators. Non-perturbative results are obtained using the twisted mass Wilson fermion formulation employing two degenerate dynamical quarks and the tree-level Symanzik improved gluon action. The simulations have been performed for pion masses in the range of about 450-260 MeV and at three values of the lattice spacing $a$ corresponding to $\beta =3.9,4.05,4.20$. Subtraction of $\mathcal{O}(a^2)$ terms is carried out by performing the perturbative evaluation of these operators at 1-loop and up to $\mathcal{O}(a^2)$. The renormalization conditions are defined in the RI${}^{\prime }$-MOM scheme, for both perturbative and non-perturbative results. The renormalization 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 $\overline{\mathrm{MS}}$ at 2 GeV using 3-loop perturbative results for the conversion factors.

ETM Collaboration, 25 pages, 15 figures. Improvement on the continuum extrapolation and clarification on the estimate of the systematic errors. Typos corrected

References in corpus (1)

• Ab-initio Determination of Light Hadron Masses

Cited by in corpus (5)

• Moments of nucleon generalized parton distributions from lattice QCD
• Two loop renormalization of the n = 2 Wilson operator in the RI'/SMOM scheme
• Hadron Structure and Form Factors
• Amplitudes for the n = 3 moment of the Wilson operator at two loops in the RI/'SMOM scheme
• Nucleon Structure in Lattice QCD using twisted mass fermions