τlepton decays and CVC

V. A. Cherepanov, S. I. Eidelman

We use experimental data on $e^{+}{e}^{-}\to \eta ({\eta }^{\prime }){\pi }^{+}{\pi }^{-}$ and conservation of vector current to estimate the branching fractions of ${\tau }^{-}$ decay to $\eta ({\eta }^{\prime }){\pi }^{-}{\pi }^0{\nu }_{\tau }$. The…