Semileptonic baryonic B decays

Abstract

We study the semileptonic $B\to \mathbf{B}\overline{{\mathbf{B}}^{\prime }}L{\overline{L}}^{\prime }$ decays with $\mathbf{B}{\overline{\mathbf{B}}}^{\prime }$ ($L{\overline{L}}^{\prime }$) representing a baryon (lepton) pair. Using the new determination of the $B\to \mathbf{B}\overline{{\mathbf{B}}^{\prime }}$ transition form factors, we obtain $\mathcal{B}(B^{-}\to p\overline{p}{\mu }^{-}{\overline{\nu }}_{\mu })=(5.4\pm 2.0)\times {10}^{-6}$ agreeing with the current data. Besides, $\mathcal{B}(B^{-}\to \mathrm{\Lambda }\overline{p}\nu \overline{\nu })=(3.5\pm 1.0)\times {10}^{-8}$ is calculated to be 20 times smaller than the previous prediction. In particular, we predict $\mathcal{B}({\overline{B}}_s^0\to p\overline{\mathrm{\Lambda }}{e}^{-}{\overline{\nu }}_e,p\overline{\mathrm{\Lambda }}{\mu }^{-}{\overline{\nu }}_{\mu },p\overline{\mathrm{\Lambda }}{\tau }^{-}{\overline{\nu }}_{\tau })=(2.1\pm 0.6,2.1\pm 0.6,1.7\pm 1.0)\times {10}^{-6}$ and $\mathcal{B}({\overline{B}}_s^0\to \mathrm{\Lambda }\overline{\mathrm{\Lambda }}\nu \overline{\nu })=(0.8\pm 0.2)\times {10}^{-8}$, which can be accessible to the LHCb experiment.