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arXiv · hep-ex/0111091

Further Evidence for the Decay K+ to pi+ neutrino-antineutrino

E787 Collaboration
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Abstract

Additional evidence for the rare kaon decay K+ to pi+ neutrino-antineutrino has been found in a new data set with comparable sensitivity to the previously reported result. One new event was observed in the pion momentum region examined, 211<P<229 MeV/c, bringing the total for the combined data set to two. Including all data taken, the backgrounds were estimated to contribute 0.15 pm 0.05 events. The branching ratio is B=1.57^{+1.75}_{-0.82} 10^{-10}.

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E787 Collaboration. 2002-01-11. Further Evidence for the Decay K+ to pi+ neutrino-antineutrino. https://doi.org/10.1103/physrevlett.88.041803

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