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 ϕare described with the help of two form factors. The values for the decay widths of the processes K^*' --> ρK, K^*' --> K^* π, K^*'--> K π, ϕ' --> K^* K, ϕ' --> KK, K' --> K ρ, K' --> K^* πand K' --> K 2πare obtained in qualitative agreement with the experimental data.