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

First radial excitations of the scalar-meson nonet and of the pseudoscalar mesons eta and eta' are described within a nonlocal chiral quark model of t he Nambu-Jona-Lasinio type with 't Hooft interaction. In this model, simple form factors are used, which allows us to describe first radial excitation s of the mesons and to retain the gap equations describing spontaneous brea kdown of chiral symmetry in the standard form. The external parameters of f orm factors are fixed by the masses of excited pseudoscalar mesons, and the same form factors are used to predict the masses of excited scalar mesons. The strong decays of excited scalar mesons and of eta and eta' mesons are described in satisfactory agreement with experimental data. (C) 2000 MAIK " Nauka/Interperiodica".