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arXiv · hep-ex/0512068

Measurement of K^+ \to π^0 μ^+ νγdecay using stopped kaons

E470 Collaboration·S. Shimizu·K. Horie·M. A. Aliev·Y. Asano·T. Baker·P. Depommier·M. Hasinoff·Y. Igarashi·J. Imazato·A. P. Ivashkin·M. M. Khabibullin·A. N. Khotjantsev·Y. G. Kudenko·A. S. Levchenko·G. Y. Lim·J. A. Macdonald·O. V. Mineev·C. Rangacharyulu·S. Sawada
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Abstract

The K^+ \to π^0 μ^+ νγ($K_{μ3 γ}$) decay has been measured with stopped positive kaons at the KEK 12 GeV proton synchrotron. A $K_{μ3 γ}$ sample containing 125 events was obtained. The partial branching ratio $Br(K_{μ3 γ}, E_γ>30 {\rm MeV}, θ_{μ^+ γ}>20^{\circ})$ was found to be $[2.4 \pm 0.5(stat) \pm 0.6(syst)]\times 10^{-5}$, which is in good agreement with theoretical predictions.

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E470 Collaboration, S. Shimizu, K. Horie, M. A. Aliev, Y. Asano, T. Baker, P. Depommier, M. Hasinoff, Y. Igarashi, J. Imazato, A. P. Ivashkin, M. M. Khabibullin, A. N. Khotjantsev, Y. G. Kudenko, A. S. Levchenko, G. Y. Lim, J. A. Macdonald, O. V. Mineev, C. Rangacharyulu, S. Sawada. 2005-12-26. Measurement of K^+ \to π^0 μ^+ νγdecay using stopped kaons. https://doi.org/10.1016/j.physletb.2005.12.045

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