An Improved upper limit on the decay K^+ -> pi^+ mu^+ e^-
/ Authors
A. Sher, R. Appel, G. Atoyan, B. Bassalleck, D. Bergman, N. Cheung, S. Dhawan, H. Do, J. Egger, S. Eilerts
and 17 more authors
W. Harold, V. Issakov, H. Kaspar, D. Kraus, D. Lazarus, P. Lichard, J. Lowe, J. Lozano, H. Ma, W. Majid, S. Pislak, A. Poblaguev, P. Řehák, A. Sher, J. Thompson, P. Truoel, M. Zeller
/ Abstract
Based on results of a search for the lepton-family-number-violating decay $K^+ \to \pi^+\mu^+ e^-$ with data collected by experiment E865 at the Alternating Gradient Synchrotron of Brookhaven National Laboratory, we place an upper limit on the branching ratio at $2.1 \times 10^{-11}$ (90% C.L.). Combining the results with earlier E865 data and those of a previous experiment, E777, an upper limit on the branching ratio of $1.3 \times 10^{-11}$ (90% C.L.) is obtained.
Journal: Physical Review D