Study of $b$-hadron decays to $\hat{I}{›}_c^{+}{h}^{-}{h}^{\prime -}$ final states

Abstract

Decays of $\hat{I}{ž}_b^{-}$ and $\hat{I}{\text{c◯}}_b^{-}$ baryons to $\hat{I}{›}_c^{+}{h}^{-}{h}^{\prime -}$ final states, with $h^{-}{h}^{\prime -}$ being $\ddot{I}{€}^{-}\ddot{I}{€}^{-}$, $K^{-}\ddot{I}{€}^{-}$ and $K^{-}{K}^{-}$ meson pairs, are searched for using data collected with the LHCb detector. The data sample studied corresponds to an integrated luminosity of $8.7{\mathrm{fb}}^{-1}$ of $pp$ collisions collected at centre-of-mass energies $\sqrt{s}=7$, $8$ and $13\mathrm{Te}\mathrm{V}$. The products of the relative branching fractions and fragmentation fractions for each signal mode, relative to the $B^{-}\to \hat{I}{›}_c^{+}\overline{p}\ddot{I}{€}^{-}$ mode, are measured, with $\hat{I}{ž}_b^{-}\to \hat{I}{›}_c^{+}{K}^{-}\ddot{I}{€}^{-}$, $\hat{I}{ž}_b^{-}\to \hat{I}{›}_c^{+}{K}^{-}{K}^{-}$ and $\hat{I}{\text{c◯}}_b^{-}\to \hat{I}{›}_c^{+}{K}^{-}{K}^{-}$ decays being observed at over $5\ddot{I}ƒ$ significance. The $\hat{I}{ž}_b^{-}\to \hat{I}{›}_c^{+}{K}^{-}\ddot{I}{€}^{-}$ mode is also used to measure the $\hat{I}{ž}_b^{-}$ production asymmetry, which is found to be consistent with zero. In addition, the $B^{-}\to \hat{I}{›}_c^{+}\overline{p}{K}^{-}$ decay is observed for the first time, and its branching fraction is measured relative to that of the $B^{-}\to \hat{I}{›}_c^{+}\overline{p}\ddot{I}{€}^{-}$ mode.

All figures and tables, along with machine-readable versions and any supplementary material and additional information, are available at https://lbfence.cern.ch/alcm/public/analysis/full-details/1789