In an experiment to search for the decay KL0ee using the 12-GeV Proton Synchrotron at KEK, we observed 18 events with the e+e- effective mass greater than 470 MeV/c2. They are presumed to come mainly from the decay KL0e+e-e+e-. Subtracting the background from the decay KL0ee and the external conversion of in the decays KL0 and KL0ee, the branching ratio of the decay KL0e+e-e+e- is estimated to be (621)×10-8. It is consistent with the previous experimental values.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)