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arXiv · 1212.4012

Precision Measurement of the Ratio of the Charged Kaon Leptonic Decay Rates

The NA62 collaboration
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Abstract

A precision measurement of the ratio RK of the rates of kaon leptonic decays K+- --> e nu and K+- --> mu nu with the full data sample collected by the NA62 experiment at CERN in 2007-2008 is reported. The result, obtained by analysing ~150000 reconstructed K+- --> e nu candidates with 11% background contamination, is RK = (2.488+-0.010)*10^{-5}, in agreement with the Standard Model expectation.

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The NA62 collaboration. 2012-12-17. Precision Measurement of the Ratio of the Charged Kaon Leptonic Decay Rates. https://arxiv.org/abs/1212.4012

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