Measurement of the branching ratio of ${\bar{B}}^0\to D^{\ast +}{\tau }^{-}{\bar{\nu }}_{\tau }$ relative to ${\bar{B}}^0\to D^{\ast +}{\ell }^{-}{\bar{\nu }}_{\ell }$ decays with a semileptonic tagging method

Y. Sato, T. Iijima, K. Adamczyk +170

We report a measurement of the ratio $\mathcal{R}(D^{\ast })=\mathcal{B}({\bar{B}}^0\to D^{\ast +}{\tau }^{-}{\bar{\nu }}_{\tau })/\mathcal{B}({\bar{B}}^0\to D^{\ast +}{\ell }^{-}{\bar{\nu }}_{\ell })$, where $\ell$ d…