Gauge covariant approach to the electroweak interactions of mesons in the Nambu–Jona-Lasinio model with spin-1 states

Abstract

An extended Nambu–Jona-Lasinio (NJL) model with chiral group [Formula: see text] and spin-0 and spin-1 four quark interactions is used to develop the gauge covariant approach to the diagonalization of the [Formula: see text] mixing in the presence of electroweak forces. This allows for manifestly gauge covariant description of both the non-anomalous and anomalous parts of the effective Lagrangian. It is shown that in the non-anomalous sector the theory is equivalent to the standard non-covariant approach.