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arXiv · hep-ex/0403036

Improved Measurement of the K+ to pi+ nu nubar Branching Ratio

E949 Collaboration·A. V. Artamonov
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Abstract

An additional event near the upper kinematic limit for K+ to pi+ nu nubar has been observed by Experiment E949 at Brookhaven National Laboratory. Combining previously reported and new data, the branching ratio is B(K+ to pi+ nu nubar)= 1.47 (+1.30, - 0.89) x 10-10 based on three events observed in the pion momentum region 211<P<229 MeV/c. At the measured central value of the branching ratio, the additional event had a signal-to-background ratio of 0.9.

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E949 Collaboration, A. V. Artamonov. 2004-07-14. Improved Measurement of the K+ to pi+ nu nubar Branching Ratio. https://doi.org/10.1103/physrevlett.93.031801

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