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First search for $K_{L}\toπ^{0}π^{0}ν\barν$

J. Nix
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Abstract

The first search for the rare kaon decay $\kppnn$ has been performed by the E391a collaboration at the KEK 12-GeV proton synchrotron. An upper limit of $4.7\times10^{-5}$ at the 90 % confidence level was set for the branching ratio of the decay $\kppnn$ using about 10 % of the data collected during the first period of data taking. First limits for the decay mode $\kppP$, where $P$ is a pseudoscalar particle, were also set.

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J. Nix. 2007-08-02. First search for $K_{L}\toπ^{0}π^{0}ν\barν$. https://doi.org/10.1103/physrevd.76.011101

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