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arXiv · hep-ex/9811038

New Limit on Muon and Electron Lepton Number Violation from $K^0_L \to μ^\pm e^\mp$ Decay

D. Ambrose
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Abstract

The most sensitive experiment to date to search for the muon and electron lepton number violating decay $K^0_L \to μ^\pm e^\mp$ has detected no events consistent with this process. Based on this result, the 90% confidence level upper limit on the branching fraction is $B(K^0_L \to μ^\pm e^\mp) < 4.7\times10^{-12}$.

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D. Ambrose. 1998-11-24. New Limit on Muon and Electron Lepton Number Violation from $K^0_L \to μ^\pm e^\mp$ Decay. https://doi.org/10.1103/physrevlett.81.5734

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