Evidence for the decay B0→p¯pπ0

Abstract

We report a search for the charmless baryonic decay B0→p¯pπ0 with a data sample corresponding to an integrated luminosity of 711 fb−1 containing (772±10)×106 B¯B pairs. The data were collected by the Belle experiment running on the Υ(4S) resonance at the KEKB e+e− collider. We measure a branching fraction B(B0→p¯pπ0)=(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.