Test of lepton-flavor universality in $B\to K^{\ast }{\ell }^{+}{\ell }^{-}$ decays at Belle

Belle Collaboration, S. Wehle, I. Adachi +179

We present a measurement of $R_{K^{\ast }}$, the branching fraction ratio $\mathcal{B}(B\to K^{\ast }{\mu }^{+}{\mu }^{-})$/ $\mathcal{B}(B\to K^{\ast }{e}^{+}{e}^{-})$, for both charged and neutral $B$ meso…