Gauge Invariance and Ward Identities in a Massive-Vector-Meson Model

Abstract
Normal-product techniques are applied to the study of gauge invariance in a massive-vector-meson model in renormalized perturbation theory. Composite fields are defined which are invariant under a one-parameter family of covariant gauge transformations. Ward identities are derived for Green's functions involving an arbitrary number of vector and axialvector currents. The lack of lowest-order radiative corrections to the triangle anomaly of the axial-vector Ward identity is verified using Bogoliubov-Parasiuk-Hepp-Zimmermann methods.