First measurement of time-dependent $CP$ violation in the flavor-changing neutral-current decay $B^0\to K_S^0{\mu }^{+}{\mu }^{-}$

LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb +1165

A flavor-tagged time-dependent analysis of $B^0\to K_S^0{\mu }^{+}{\mu }^{-}$ decays is performed across the full dimuon mass range excluding the $J/\psi$ and $\psi (2S)$ resonance re…