PHYSICAL REVIEW D, PARTICLES, FIELDS, GRAVITATION, AND COSMOLOGY
Abstract
We report the observation of the baryonic decay B ̄0→Λc+p ̄K-K+ using a data sample of 471×106 BB ̄ pairs produced in e+e- annihilations at s=10.58GeV. This data sample was recorded with the BABAR detector at the PEP-II storage ring at SLAC. We find B(B ̄0→Λc+p ̄K-K+)=(2.5±0.4(stat)±0.2(syst)±0.6B(Λc+))×10-5, where the uncertainties are statistical, systematic, and due to the uncertainty of the Λc+→pK-π+ branching fraction, respectively. The result has a significance corresponding to 5.0 standard deviations, including all uncertainties. For the resonant decay B ̄0→Λc+p ̄φ, we determine the upper limit B(B ̄0→Λc+p ̄φ)<1.2×10-5 at 90% confidence level.