The decay $\tau \to K^{\ast 0}(892)K^{-}{\nu }_{\tau }$ in the extended NJL model

Abstract

In the extended Nambu -- Jona-Lasinio model, the decay width of $\tau \to K^{\ast 0}(892)K^{-}{\nu }_{\tau }$ is calculated. The contributions from the contact diagram and diagrams with intermediate axial-vector, vector and pseudoscalar mesons in the ground and first radially excited states are taken into account. It is shown that axial-vector and vector channel with a contact diagram give a dominant contribution to the decay width. The obtained results for the decay width $\tau \to K^{\ast 0}(892)K^{-}{\nu }_{\tau }$ are in satisfactory agreement with experimental data. A prediction for differential distribution over the invariant mass of the meson pair $K^{\ast 0}(892)K^{-}$ is given.

Comments: 7 pages, 3 figures