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Observation of the rare decay K_S -> pi^0mu^+mu^-

J. R. Batley
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Abstract

A search for the decay K_S -> pi^0mu^+mu^- has been made by the NA48/1 Collaboration at the CERN SPS accelerator. The data were collected during 2002 with a high-intensity K_S beam. Six events were found with a background expectation of 0.22^+0.18_-0.11 event. Using a vector matrix element and unit form factor, the measured branching ratio is B(K_S -> pi^0mu^+mu^-)=[2.9^+1.5_-1.2(stat)+/-0.2(syst)]x10^{-9}.

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J. R. Batley. 2004-09-02. Observation of the rare decay K_S -> pi^0mu^+mu^-. https://doi.org/10.1016/j.physletb.2004.08.058

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