Test of lepton flavour universality with $B^{+}\to K^{+}{\pi }^{+}{\pi }^{-}{\ell }^{+}{\ell }^{-}$ decays

LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb +1132

The first test of lepton flavor universality between muons and electrons using $B^{+}\to K^{+}{\pi }^{+}{\pi }^{-}{\ell }^{+}{\ell }^{-}$ ($\ell =e,\mu$) decays is presented. The measurement is performed with d…