First observations of the rare decays $B^{+}->K^{+}{\pi }^{+}{\pi }^{-}{\mu }^{+}{\mu }^{-}$ and $B^{+}->\varphi K^{+}{\mu }^{+}{\mu }^{-}$

LHCb collaboration, R. Aaij, B. Adeva +697

First observations of the rare decays $B^{+}\to K^{+}{\pi }^{+}{\pi }^{-}{\mu }^{+}{\mu }^{-}$ and $B^{+}\to \varphi K^{+}{\mu }^{+}{\mu }^{-}$ are presented using data corresponding to an integrated luminosity of $3.0\,{…