First observation of the decay K+ -> e+ nu mu+ mu-
/ Authors
H.Ma, R. Appel, G. Atoyan, B. Bassalleck, D. Bergman, N. Cheung, S. Dhawan, H. Do, J. Egger, S. Eilerts
and 16 more authors
W. Herold, V. Issakov, H. Kaspar, D. Kraus, D. Lazarus, P. Lichard, J. Lowe, J. Lozano, W. Majid, S. Pislak, A. Poblaguev, P. Řehák, A. Sher, J. Thompson, P. Truoel, M. Zeller
/ 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.
Journal: Physical Review D