Recent Results on $\tau$ Decays

Abstract

We present herein new results from Belle on the ${\tau }^{-}\to {\pi }^{-}{\nu }_{\tau }{\ell }^{+}{\ell }^{-}$ branching fraction and from BABAR on the ${\tau }^{-}\to K^{-}(0,1,2,3){\pi }^0{\nu }_{\tau }$, ${\tau }^{-}\to {\pi }^{-}(3,4){\pi }^0{\nu }_{\tau }$ and ${\tau }^{-}\to K^{-}{K}_{\mathrm{S}}^0{\nu }_{\tau }$ branching fractions. From the $K^{-}{K}_{\mathrm{S}}^0$ mass spectrum we determine the spectral function. The improved branching fraction measurements of the ${\tau }^{-}\to K^{-}(0,1,2,3){\pi }^0{\nu }_{\tau }$ decays are used to determine $|V_{\mathrm{us}}|$ from ${\tau }^{-}\to X_{\mathrm{s}}^{-}{\nu }_{\tau }$ inclusive decays.

8 pages, 11 figures, plenary talk at the Flavor Physics and CP Violation conference, FPCP2019 in Victoria, Canada