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New limit on the $K^0_L \to π^0 ν\barν$ decay rate

E391a Collaboration·J. K. Ahn
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Abstract

The first dedicated experiment for the rare kaon decay $K^0_L \to π^0 ν\barν$ has been performed by the E391a collaboration at the KEK 12-GeV proton synchrotron. A new upper limit of $2.1 \times 10^{-7}$ at the 90% confidence level was set for the branching ratio of the decay $K^0_L \to π^0 ν\barν$ using about 10% of the data collected during the first period of data taking.

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E391a Collaboration, J. K. Ahn. 2006-09-18. New limit on the $K^0_L \to π^0 ν\barν$ decay rate. https://doi.org/10.1103/physrevd.74.051105%2010.1103%2Fphysrevd.74.079901

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