Prefer a chat interface with context about you and your work?
Upper limit on the branching ratio for the decay<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msup><mml:mi>π</mml:mi><mml:mn>0</mml:mn></mml:msup><mml:mo>→</mml:mo><mml:mi>ν</mml:mi><mml:mover accent="true"><mml:mi>ν</mml:mi><mml:mo>¯</mml:mo></mml:mover></mml:math>
A sample of kinematically identified K+→π+π0 decays obtained with the E949 detector was used to search for the helicity-suppressed decay π0→ν¯ν resulting in an upper limit of 2.7×10−7 at 90% confidence level. The upper limit is also applicable to π0 decays into unknown weakly-interacting particles.Received 11 June 2005DOI:https://doi.org/10.1103/PhysRevD.72.091102©2005 American Physical …