Experimental search for the decay long-lived neutral kaon going to muonium

Jon Erik Urheim, University of Pennsylvania


An experimental study of very rare decays of neutral kaons has been carried out at a new neutral beam line at the Alternating-Gradient Synchrotron at Brookhaven National Laboratory. One focus of this study was a search for the lepton-flavor violating decay $K\sbsp{L}{0}\to\mu e$. No candidate events indicating occurrence of this process were found. Measurement of the experimental sensitivity was performed by simultaneous observation of the decay $K\sbsp{L}{0}\to\pi\sp+\pi\sp-$. This yielded a limited at the 90% confidence level on the branching ratio $B(K\sbsp{L}{0}\to\mu e$) $<$ 2.2 $\times$ 10$\sp{-10}$. This limit represents a substantial improvement over previous limits on the rate for this process.

Subject Area

Particle physics

Recommended Citation

Urheim, Jon Erik, "Experimental search for the decay long-lived neutral kaon going to muonium" (1990). Dissertations available from ProQuest. AAI9026663.