The pseudoscalar and vector excited mesons in the U(3)*U(3) chiral model

TL;DR

This paper develops a chiral U(3)*U(3) Lagrangian including first radial excitations of mesons, derived from a bosonized NJL quark model, and calculates their masses and decay constants.

Contribution

It introduces a novel chiral Lagrangian with radial excitations based on a bosonized NJL model, incorporating form factors with a single parameter each.

Findings

Calculated masses of excited mesons.

Determined weak decay constants for excited states.

Established a framework for excited meson phenomenology.

Abstract

A chiral U(3)*U(3) Lagrangian containing, besides the usual meson fields, their first radial excitations is constructed. The Lagrangian is derived by bosonization of the Nambu-Jona-Lasinio quark model with separable non-local interactions, with form factors corresponding to 3-dimensional ground and excited state wave functions. The spontaneous breaking of chiral symmetry is governed by the NJL gap equation. The first radial excitations of the pions, kaons and vector meson nonet are described with the help of five different form factors. Each form factor contains only one arbitrary parameter. The masses of these meson states and the weak decay constants $F_{\pi'}, F_K and F_{K'}$ are calculated.