Evidence for the decay B0 →p p π0

Abstract

We report a search for the charmless baryonic decay B0→ppπ0 with a data sample corresponding to an integrated luminosity of 711 fb-1 containing (772±10)×106 BB pairs. The data were collected by the Belle experiment running on the (4S) resonance at the KEKB e+e- collider. We measure a branching fraction B(B0→ppπ0)=(5.0±1.8±0.6)×10-7, where the first uncertainty is statistical and the second is systematic. The signal has a significance of 3.1 standard deviations and constitutes the first evidence for this decay mode. We also search for the intermediate two-body decays B0→Δ+p and B0→Δ-p, and set an upper limit on the branching fraction, B(B0→Δ+p)+B(B0→Δ-p)<1.6×10-6 at 90% confidence level.