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arXiv · hep-ex/9708012

Observation of the Decay K+ --> pi+ mu+ mu-

E787 Collaboration·S. Adler·M. S. Atiya·I-H. Chiang·J. S. Frank·J. S. Haggerty·T. F. Kycia·K. K. Li·L. S. Littenberg·A. Sambamurti·A. Stevens·R. C. Strand·C. Witzig·W. C. Louis·D. S. Akerib·M. Ardebili·M. R. Convery·M. M. Ito·D. R. Marlow·R. A. McPherson·P. D. Meyers·M. A. Selen·F. C. Shoemaker·A. J. S. Smith·E. W. Blackmore·D. A. Bryman·L. Felawka·A. Konaka·Y. Kuno·J. A. Macdonald·T. Numao·P. Padley·J-M. Poutissou·R. Poutissou·J. Roy·A. S. Turcot·P. Kitching·T. Nakano·M. Rozon·R. Soluk
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Abstract

We have observed the rare decay K+ --> pi+ mu+ mu- and measured the branching ratio Gamma(K+ --> pi+ mu+ mu-)/Gamma(K+ --> all) = (5.0 +/- 0.4 (stat.) +/- 0.7 (sys.) +/- 0.6 (theor.)) x 10^{-8}. We compare this result with predictions from chiral perturbation theory and estimates based on the decay K+ --> pi+ e+ e-.

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E787 Collaboration, S. Adler, M. S. Atiya, I-H. Chiang, J. S. Frank, J. S. Haggerty, T. F. Kycia, K. K. Li, L. S. Littenberg, A. Sambamurti, A. Stevens, R. C. Strand, C. Witzig, W. C. Louis, D. S. Akerib, M. Ardebili, M. R. Convery, M. M. Ito, D. R. Marlow, R. A. McPherson, P. D. Meyers, M. A. Selen, F. C. Shoemaker, A. J. S. Smith, E. W. Blackmore, D. A. Bryman, L. Felawka, A. Konaka, Y. Kuno, J. A. Macdonald, T. Numao, P. Padley, J-M. Poutissou, R. Poutissou, J. Roy, A. S. Turcot, P. Kitching, T. Nakano, M. Rozon, R. Soluk. 1997-10-19. Observation of the Decay K+ --> pi+ mu+ mu-. https://doi.org/10.1103/physrevlett.79.4756

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