The first search for the rare kaon decay KL→π0π0νν̄ has been performed by the E391a collaboration at the KEK 12-GeV proton synchrotron. An upper limit of 4.7×10-5 at the 90% confidence level was set for the branching ratio of the decay KL→π0π0νν̄ using about 10% of the data collected during the first period of data taking. First limits for the decay mode KL→π0π0P, where P is a pseudoscalar particle, were also set.
ASJC Scopus subject areas
- Physics and Astronomy(all)
- Nuclear and High Energy Physics
- Mathematical Physics