Effects of fermions in one-loop propagators in the Curci-Ferrari-Delbourgo-Jarvis gauge

TL;DR

This paper computes the one-loop quark propagator in the CFDJ gauge, revealing how finite gauge parameters influence infrared behavior and suggesting the gauge's potential as an infrared-safe framework for perturbative QCD with massive gluons.

Contribution

It extends previous one-loop analyses to include dynamical quarks and studies the impact of gauge parameters on infrared properties in the CFDJ gauge.

Findings

Coupling, gluon mass, and gauge parameter freeze below a finite energy scale.

Quark dressing function Z(p) varies with gauge parameter, aligning better with lattice data.

CFDJ gauge shows promise as an infrared-safe setting for perturbative QCD.

Abstract

We present the one-loop computation of the quark propagator in the Curci-Ferrari-Delbourgo- Jarvis (CFDJ) gauge, extending previous analyses to include dynamical quarks. Using the infrared- safe renormalization scheme, we study how finite gauge parameters affect the infrared behavior of QCD correlation functions. The coupling, gluon mass, and gauge parameter are found to freeze below a finite energy scale, confirming the infrared stability of the framework. The quark dressing function Z(p) shows a change in concavity between the Landau and finite-{\xi} cases, suggesting that nonvanishing gauges may better reproduce lattice trends. These results establish the CFDJ gauge as a possible infrared-safe setting candidate for perturbative QCD with massive gluons. In the case of a consistency check from lattice calculations, it could provide a basis for future studies of the quark-gluon vertex and related observables.