Measurements of the decays B0 → ¯D0p¯p, B0 → ¯D*0p¯p, B0 → D−p¯pπ+, and B0 → D*−p¯p+

Abstract

We present measurements of branching fractions of B 0 decays to multibody final states containing protons, based on 232 × 10 6 Υ ( 4 S ) → B ¯¯¯ B decays collected with the BABAR detector at the SLAC PEP-II asymmetric-energy B factory. We measure the branching fractions B ( B 0 → ¯¯¯ D 0 p ¯ p ) = ( 1.13 ± 0.06 ± 0.08 ) × 10 − 4 , B ( B 0 → ¯¯¯ D * 0 p ¯ p ) = ( 1.01 ± 0.10 ± 0.09 ) × 10 − 4 , B ( B 0 → D − p ¯ p π + ) = ( 3.38 ± 0.14 ± 0.29 ) × 10 − 4 , and B ( B 0 → D * − p ¯ p π + ) = ( 4.81 ± 0.22 ± 0.44 ) × 10 − 4 where the first error is statistical and the second systematic. We present a search for the charmed pentaquark state, Θ c ( 3100 ) observed by H1 and put limits on the branching fraction B ( B 0 → Θ c ¯ p π + ) × B ( Θ c → D * − p ) < 14 × 10 − 6 and B ( B 0 → Θ c ¯ p π + ) × B ( Θ c → D − p ) < 9 × 10 − 6 . Upon investigation of the decay structure of the above four B 0 decay modes, we see an enhancement at low p ¯ p mass and deviations from phase-space in the ¯¯¯ D ¯ p and ¯¯¯ D p invariant mass spectra.