Studies of beauty baryons decaying to $D^{0}p\pi^{-}$ and $D^{0}pK^{-}$

We study decays of beauty baryons to the $D^{0}p\pi^{-}$ and $D^{0}pK^{-}$ final states with the data collected by LHCb in March-June 2011. We present the first observation of the Cabibbo-suppressed decay $\Lambda^0_b \to D^{0}pK^{-}$ that can be used to measure the angle of $\gamma$ of the CKM unitarity triangle. The ratio of branching fractions is measured: $\cal{B}(\Lambda^0_b \to D^{0}pK^{-})/\cal{B}(\Lambda^0_b \to D^{0}p\pi^{-})$ = 0.112 $\pm$ 0.019$^{+0.011}_{-0.014}$. We also find a hint, with 2.6$\sigma$ significance, of the neutral beauty-strange baryon $\Xi_b^0$ reconstructed in the exclusive final state $D^{0}pK^{-}$