Search for the rare decay K+-->π+e+e-
Abstract
A search for the rare decay K+-->π+e+e- has been carried out at the Lawrence Berkeley Laboratory using a sparkostrictive wire-chamber spectrometer. Analysis programs identified events with three tracks or with two tracks of which one was an electron and the other a positron. Analysis of the three-track events yields a branching ratio Γ(K+-->π+e+e- )Γ(K+-->all)<1.7×10-6 (90% confidence). The two-track events, analyzed by searching for sparks on a possible pion track, yield a limit of Γ(K+-->π+e+e- )Γ(K+-->all)<2.7×10-7 (90% confidence). The latter value implies that the coupling constant for a vector neutral current must be about three orders of magnitude smaller than the coupling constant for the charged vector current.
- Publication:
-
Physical Review D
- Pub Date:
- August 1974
- DOI:
- 10.1103/PhysRevD.10.776
- Bibcode:
- 1974PhRvD..10..776C