Test of lepton flavour universality using $B^0\to D^{\ast -}{\tau }^{+}{\nu }_{\tau }$ decays with hadronic $\tau$ channels

LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb +1051

The branching fraction $\mathcal{B}(B^0\to D^{\ast -}{\tau }^{+}{\nu }_{\tau })$ is measured relative to that of the normalization mode $B^0\to D^{\ast -}{\pi }^{+}{\pi }^{-}{\pi }^{+}$ using hadronic $τ^+ \to π^+π^-π^+(π^0)\o…