Decays of excited strange mesons in the extended NJL model

Abstract

A chiral U(3)xU(3) Lagrangian, containing besides the usual meson fields their first radial excitations, is considered. The Lagrangian is derived by bosonization of the Nambu--Jona-Lasinio quark model with separable non-local interactions. The spontaneous breaking of chiral symmetry is governed by the NJL gap equation. The first radial excitations of the kaon, K^* and \phi are described with the help of two form factors. The values for the decay widths of the processes K^*' --> \rho K, K^*' --> K^* \pi, K^*'--> K \pi, \phi' --> K^* K, \phi' --> KK, K' --> K \rho, K' --> K^* \pi and K' --> K 2\pi are obtained in qualitative agreement with the experimental data.