Perturbative results for the matrix elements of the vector current and the role of different infrared regulators

TL;DR

This paper calculates the one-loop matrix elements of the vector current in QCD using perturbation theory, examining the effects of different infrared regulators and the zero momentum transfer limit.

Contribution

It provides a detailed perturbative analysis of vector current matrix elements with a focus on infrared regulation methods and their impact, extending previous axial current studies.

Findings

Computed twist-2 GPDs at one-loop accuracy

Analyzed effects of quark mass and dimensional regularization as IR regulators

Explored the zero momentum transfer limit

Abstract

We investigate the twist-2 unpolarized generalized parton distributions (GPDs) of quarks for an on-shell gluon target in quantum chromodynamics. These GPDs parametrize the leading-twist matrix elements of the nonlocal light-like flavor-singlet vector current. We compute them at one-loop accuracy in perturbation theory using a quark mass and dimensional regularization as infrared regulators. In particular, we discuss the limit of vanishing momentum transfer. The present work extends our previous related study on the axial current.