Abstract
We revisit the four-leptonic decays \({B^{-}\rightarrow\mu^{+}\mu^{-}e^{-}\bar{\nu}_{e}}\) and \({B^{-}\rightarrow e^{+}e^{-}\mu^{-}\bar{\nu}_{\mu}}\) within the framework of the Standard Model. Compared to our previous studies, nonzero lepton masses, more precise bremsstrahlung amplitude and heavy vector resonant contributions were taken into account. All calculations were performed in the method of orthogonal amplitudes. We update theoretical predictions of partial widths: \(\textrm{Br}({B^{-}\rightarrow\mu^{+}\mu^{-}e^{-}\bar{\nu}_{e}})\approx 3.7\times 10^{-8}\) and \(\textrm{Br}({B^{-}\rightarrow e^{+}e^{-}\mu^{-}\bar{\nu}_{\mu}})\approx 3.9\times 10^{-8}\) . Differential distributions and double differential distributions are presented as well.
