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First observation of the decay K+ -> e+ nu mu+ mu-

H. Ma·R. Appel·G. S. Atoyan·B. Bassalleck·D. R. Bergman·N. Cheung·S. Dhawan·H. Do·J. Egger·S. Eilerts·W. Herold·V. V. Issakov·H. Kaspar·D. E. Kraus·D. M. Lazarus·P. Lichard·J. Lowe·J. Lozano·W. Majid·S. Pislak·A. A. Poblaguev·P. Rehak·A. Sher·J. A. Thompson·P. Truoel·M. E. Zeller
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Abstract

Experiment 865 at the Brookhaven AGS has observed the decay K^+ -> e^+ nu mu^+ mu^-. The branching ratio extracted is (1.72 +/- 0.37(stat) +/- 0.17(syst) +/- 0.19(model)) x 10^{-8} where the third term in the error results from the use of a model to extrapolate into a kinematic region dominated by background.

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H. Ma, R. Appel, G. S. Atoyan, B. Bassalleck, D. R. Bergman, N. Cheung, S. Dhawan, H. Do, J. Egger, S. Eilerts, W. Herold, V. V. Issakov, H. Kaspar, D. E. Kraus, D. M. Lazarus, P. Lichard, J. Lowe, J. Lozano, W. Majid, S. Pislak, A. A. Poblaguev, P. Rehak, A. Sher, J. A. Thompson, P. Truoel, M. E. Zeller. 2006-01-13. First observation of the decay K+ -> e+ nu mu+ mu-. https://doi.org/10.1103/physrevd.73.037101

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