Observation of $\hat{I}{›}_b^0\to D^{+}p\ddot{I}{€}^{-}\ddot{I}{€}^{-}$ and $\hat{I}{›}_b^0\to D^{\ast +}p\ddot{I}{€}^{-}\ddot{I}{€}^{-}$ decays

Abstract

The multihadron decays $\hat{I}{›}_b^0\to D^{+}p\ddot{I}{€}^{-}\ddot{I}{€}^{-}$ and $\hat{I}{›}_b^0\to D^{\ast +}p\ddot{I}{€}^{-}\ddot{I}{€}^{-}$ are observed in data corresponding to an integrated luminosity of 3fb${}^{-1}$, collected in proton-proton collisions at centre-of-mass energies of 7 and 8TeV by the LHCb detector. Using the~decay $\hat{I}{›}_b^0\to \hat{I}{›}_c^{+}\ddot{I}{€}^{+}\ddot{I}{€}^{-}\ddot{I}{€}^{-}$ as a normalisation channel, the ratio of branching fractions is measured to be $$\frac{\mathcal{B}(\hat{I}{›}_b^0\to D^{+}p\ddot{I}{€}^{-}\ddot{I}{€}^{-})}{\mathcal{B}(\hat{I}{›}_b^0\to \hat{I}{›}_c^{+}\ddot{I}{€}^{+}\ddot{I}{€}^{-}\ddot{I}{€}^{-})}\times \frac{\mathcal{B}(D^{+}\to K^{-}\ddot{I}{€}^{+}\ddot{I}{€}^{+})}{\mathcal{B}(\hat{I}{›}_c^{+}\to p{K}^{-}\ddot{I}{€}^{+})}=(5.35\pm 0.21\pm 0.16)\%,$$ where the first uncertainty is statistical and the second systematic. The ratio of branching fractions for $\hat{I}{›}_b^0\to D^{\ast +}p\ddot{I}{€}^{-}\ddot{I}{€}^{-}$ and $\hat{I}{›}_b^0\to D^{+}p\ddot{I}{€}^{-}\ddot{I}{€}^{-}$ decays is found to be $$\frac{\mathcal{B}(\hat{I}{›}_b^0\to D^{\ast +}p\ddot{I}{€}^{-}\ddot{I}{€}^{-})}{\mathcal{B}(\hat{I}{›}_b^0\to D^{+}p\ddot{I}{€}^{-}\ddot{I}{€}^{-})}\times (\mathcal{B}(D^{\ast +}\to \ddot{I}{€}^0)+\mathcal{B}(D^{\ast +}\to {\hat{I}}^3))=(61.3\pm 4.3\pm 4.0)\%.$$

All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2021-040.html