Infrared regularization of non-Abelian gauge theories

Abstract

Curci and Ferrari found a unique BRS-invariant action for non-Abelian gauge theories which includes a mass term for the gauge bosons. I analyze this action. While the BRS operator is not nilpotent, the Zinn-Justin equation generalizes in a simple way so that the renormalization of the theory is consistent with the infrared regularization provided by the mass---infrared singularities and ultraviolet infinities are therefore clearly separated. Relations between renormalization constants are derived in dimensional regularization with minimal subtraction. Additional new symmetries allow a simple characterization of physical operators. A new formula is given for the gauge parameter dependence of physical operators.