Measurements of the decays B0→D0pp, B0→D*0pp, B0→D-ppπ+, and B0→D*-ppπ+

We present measurements of branching fractions of B0 decays to multibody final states containing protons, based on 232x106 Υ(4S)→BB decays collected with the BABAR detector at the SLAC PEP-II asymmetric-energy B factory. We measure the branching fractions B(B0→D0pp)=(1.13±0.06±0.08)x10-4, B(B0→D*0pp)=(1.01±0.10±0.09)x10-4, B(B0→D-ppπ+)=(3.38±0.14±0.29)x10-4, and B(B0→D*-ppπ+)=(4.81±0.22±0.44)x10-4 where the first error is statistical and the second systematic. We present a search for the charmed pentaquark state, Θc(3100) observed by H1 and put limits on the branching fraction B(B0→Θcpπ+)xB(Θc→D*-p)<14x10-6 and B(B0→Θcpπ+)xB(Θc→D-p)<9x10-6. Upon investigation of the decay structure of the above four B0 decay modes, we see an enhancement at low pp mass and deviations from phase-space in the Dp and Dp invariant mass spectra