Nonlocal regularization and spontaneously broken abelian gauge theories for an arbitrary gauge parameter

Abstract

We study the nonlocal regularization for the case of a spontaneously broken abelian gauge theory in the Rξ-gauge with an arbitrary gauge parameter ξ. We consider a simple abelian-Higgs model with chiral couplings as an example. We show that if we apply the nonlocal regularization procedure (to construct a nonlocal theory with FINITE mass parameter) to the spontaneously broken Rξ-gauge Lagrangian, using the quadratic forms as appearing in this Lagrangian, we find that a physical observable in this model, an analogue of the muon anomalous magnetic moment, evaluated to order O [g2] does indeed show ξ-dependence. We then apply the modified form of nonlocal regularization that was recently advanced and studied for the unbroken non-abelian gauge theories and discuss the resulting WT identities and ξ-independence of the S-matrix elements.