The decays $ρ^{-}\toηπ^{-}$ and $τ^{-}\toη(η')π^{-}ν$ in the NJL model

Abstract

The widths of the decays $ρ^{-}\toηπ^{-}$ and $τ^{-}\toη(η')π^{-}ν$ are calculated in the framework of the NJL model. It is shown that these decays are defined by the $u$ and $d$ quark mass difference. It leads to the suppression of these decays in comparison with the main decay modes. In the process $ρ^{-}\toηπ^{-}$ the intermediate scalar $a_0^{-}$ state is taken into account. For the $τ$ decays the intermediate states with $a_0^{-}$, $ρ^{-}(770)$ and $ρ^{-}(1450)$ mesons are used. Our estimates are compared with the results obtained in other works.