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Experimental Study of the Radiative Decays K+ -> mu+ nu e+e- and K+ -> e+ nu e+e-

A. A. Poblaguev·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·H. Ma·W. Majid·S. Pislak·P. Rehak·A. Sher·J. A. Thompson·P. Truoel·M. E. Zeller
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Abstract

Experiment 865 at the Brookhaven AGS obtained 410 K+ -> e+ nu e+e- and 2679 K+ -> mu+ nu e+e- events including 10% and 19% background. The branching ratios were measured to be (2.48+-0.14(stat.)+-0.14(syst.))x10^-8 (m_ee>150 MeV) and (7.06+-0.16+-0.26)x10^-8 (m_ee>145 MeV), respectively. Results for the decay form factors are presented.

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A. A. Poblaguev, 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, H. Ma, W. Majid, S. Pislak, P. Rehak, A. Sher, J. A. Thompson, P. Truoel, M. E. Zeller. 2002-04-05. Experimental Study of the Radiative Decays K+ -> mu+ nu e+e- and K+ -> e+ nu e+e-. https://doi.org/10.1103/physrevlett.89.061803

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