In this paper, the width of the decay $\tau \rightarrow K^{ -}\pi^{ 0}\nu_{ \tau}$ is calculated in the framework of the Nambu-Jona-Lasinio model. The contributions of the intermediate vector $K^{ *}(892)$ and scalar $K_{ 0}^{ *}(800)$ mesons are taken into account. It is shown that the main contribution to the width of this decay is given by the subprocesses with the intermediate $W$-boson and vector $K^{ *}(892)$ meson. The scalar channel with the intermediate $K_{ 0}^{ *}(800)$ meson gives an insignificant contribution. In Appendix, it is shown that the contribution of the subprocess with the intermediate ${ K^{ *}}'(1410)$ meson is negligible as well. The obtained results are in satisfactory agreement with the experimental data.
Categories: hep-ph