A study of $\overline {B}{^0} \to D^0 p\bar{p}$ decays with the LHCb experiment

This thesis presents the results of the study of $\overline {B}{^0} \to D^0 p\bar{p}$ decays with the LHCb experiment. The data of proton-proton collisions were taken with the LHCb detector at centre-of-mass energies of 7 TeV and 8 TeV, corresponding to an integrated luminosity of about $3\text {fb}^{-1}$. The branching fraction of $\overline {B}{^0} \to D^0 p\bar{p}$ decays has been already measured by the $B$ Factories Babar and Belle and will be verified with the higher statistics of the LHCb data. The relative branching fraction of $\overline {B}{^0} \to D^0 p\bar{p}$ decays to $\overline {B}{^0} \to D^0 pi^+ \pi^-$ decays is measured to be \begin{align} \frac {\mathcal B(\overline B{^0} \to D^0p\bar{p})}{\mathcal B(\overline B{^0} \to D^0 \pi^+ \pi^-} = (9.2 \pm 0.7 (stat) \pm 0.6 (syst)) \times 10^{-2}. \end{align} Using the world average of the $\overline B{^0} \to D^0 \pi^+ \pi^- $ branching fraction results in a branching fraction of \begin{align} \mathcal B(\overline B{^0} \to D^0p\bar{p}) = (0.81 \pm 0.06 (stat) \pm 0.06 (syst) \pm 0.05 (norm)) \times 10^{-4} \end{align} for $\overline {B}{^0} \to D^0 p\bar{p}$ decays. This is a deviation of less than 2$\sigma$ from Babar's branching fraction measurement. The invariant baryon-antibaryon mass of $\overline {B}{^0} \to D^0 p\bar{p}$ shows the expected behaviour of the so-called threshold enhancement for small invariant masses and an asymmetric behaviour of the angular distribution of the $p \bar {p}$ system at rest. Further structures are observed for the invariant $D^0 p$ mass.