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An Improved Limit on the Rate Of Decay K+ -> pi+ mu+ e-

R. Appel·G. S. Atoyan·B. Bassalleck·D. R. Bergman·D. N. Brown·N. Cheung·S. Dhawan·H. Do·J. Egger·S. Eilerts·C. Felder·H. Fischer·M. Gach·W. Herold·V. V. Issakov·H. Kaspar·D. E. Kraus·D. M. Lazarus·L. Leipuner·P. Lichard·J. Lowe·J. Lozano·H. Ma·W. Majid·W. Menzel·S. Pislak·A. A. Poblaguev·V. E. Postoev·A. L. Proskurjakov·P. Rehak·P. Robmann·A. Sher·J. A. Thompson·P. Truoel·H. Weyer·M. E. Zeller
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Abstract

The experiment E865 at BNL places an upper limit on the branching ratio for the decay K+ -> pi+ mu+ e- of 3.9x10^-11 (90% C.L.). Along with with other results this yields a combined upper limit on this branching ratio of 2.8x10^-11. A new upper limit on the branching ratio for pi0 -> mu+ e- of 3.8x10^-10 (90% C.L.) is also established. The experiment and analysis are described.

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R. Appel, G. S. Atoyan, B. Bassalleck, D. R. Bergman, D. N. Brown, N. Cheung, S. Dhawan, H. Do, J. Egger, S. Eilerts, C. Felder, H. Fischer, M. Gach, W. Herold, V. V. Issakov, H. Kaspar, D. E. Kraus, D. M. Lazarus, L. Leipuner, P. Lichard, J. Lowe, J. Lozano, H. Ma, W. Majid, W. Menzel, S. Pislak, A. A. Poblaguev, V. E. Postoev, A. L. Proskurjakov, P. Rehak, P. Robmann, A. Sher, J. A. Thompson, P. Truoel, H. Weyer, M. E. Zeller. 2000-05-10. An Improved Limit on the Rate Of Decay K+ -> pi+ mu+ e-. https://doi.org/10.1103/physrevlett.85.2450

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