We study the singly Cabibbo suppressed decays Λc+→pη and Λc+→pπ0 using Λc+Λ- pairs produced by e+e- collisions at a center-of-mass energy of s=4.6 GeV. The data sample was collected by the BESIII detector at the BEPCII collider and corresponds to an integrated luminosity of 567 pb-1. We find the first evidence for the decay Λc+→pη with a statistical significance of 4.2σ and measure its branching fraction to be B(Λc+→pη)=(1.24±0.28(stat)±0.10(syst))×10-3. No significant Λc+→pπ0 signal is observed. We set an upper limit on its branching fraction B(Λc+→pπ0)<2.7×10-4 at the 90% confidence level.
- NONLEPTONIC DECAYS
- CHARMED BARYONS