Radial excitations of scalar and \eta, \eta' mesons in a chiral quark model

TL;DR

This paper models the first radial excitations of scalar and pseudoscalar mesons using a nonlocal chiral quark model, successfully predicting their masses and decay properties.

Contribution

It introduces a simple form factor approach within a nonlocal NJL model to describe radial excitations while maintaining chiral symmetry breaking dynamics.

Findings

Predicted masses of excited scalar and pseudoscalar mesons agree with experimental data.

Described strong decay widths of excited mesons consistent with observations.

Established a unified framework for meson excitations using fixed form factors.

Abstract

First radial excitations of the scalar meson nonet and pseudoscalar mesons \eta, \eta' are described in a nonlocal chiral quark model of the Nambu--Jona-Lasinio type with 't Hooft interaction. In this model simple form factors are used, which allows us to describe first radial excitations of the mesons and to conserve the gap equations describing spontaneous breaking of chiral symmetry in the standard form. The external parameters of form factors are fixed by masses of excited pseudoscalar mesons and the same form factors are used for predicting the masses of excited scalar mesons. Strong decays of excited scalar mesons and \eta, \eta' mesons are described in satisfactory agreement with experiment.