Gluon mass generation without seagull divergences

TL;DR

This paper demonstrates a method to eliminate seagull divergences in dynamical gluon mass generation using a specific identity in dimensional regularization, leading to a unique solution for the gluon mass and effective charge.

Contribution

It introduces a novel approach that removes divergences and yields a unique, scheme-independent solution for gluon mass and effective charge in QCD.

Findings

Gluon mass remains finite and scheme-independent.

Effective charge freezes in the infrared.

Gluon mass exhibits power-law running in the ultraviolet.

Abstract

Dynamical gluon mass generation has been traditionally plagued with seagull divergences, and all regularization procedures proposed over the years yield finite but scheme-dependent gluon masses. In this work we show how such divergences can be eliminated completely by virtue of a characteristic identity, valid in dimensional regularization. The ability to trigger the aforementioned identity hinges crucially on the particular Ansatz employed for the three-gluon vertex entering into the Schwinger-Dyson equation governing the gluon propagator. The use of the appropriate three-gluon vertex brings about an additional advantage: one obtains two separate (but coupled) integral equations, one for the effective charge and one for the gluon mass. This system of integral equations has a unique solution, which unambiguously determines these two quantities. Most notably, the effective charge freezes in the infrared, and the gluon mass displays power-law running in the ultraviolet, in agreement with earlier considerations.