Improved limit on the rate of the decay K+ --> pi(+)m(+)e(-)
/ Authors
R. Appel, G. Atoyan, B. Bassalleck, D. Bergman, D. N. Brown, N. Cheung, S. Dhawan, H. Do, J. Egger, S. Eilerts
and 26 more authors
C. Felder, H. Fischer, M. Gach, W. Herold, V. Issakov, H. Kaspar, D. Kraus, D. Lazarus, L. Leipuner, P. Lichard, J. Lowe, J. Lozano, H. Ma, W. Majid, W. Menzel, S. Pislak, A. Poblaguev, V. Postoev, A. L. Proskurjakov, P. Řehák, P. Robmann, A. Sher, J. Thompson, P. Truöl, H. Weyer, M. Zeller
/ Abstract
We report results of a search for the lepton-family number violating decay K+-->pi(+)m(+)e(-) from data collected by experiment E865 in 1996 at the Alternating Gradient Synchroton of Brookhaven National Laboratory. We place an upper limit on the branching ratio at 3.9x10(-11) ( 90% C.L.). Together with results based on data collected in 1995 and an earlier experiment, E777, this result establishes a combined 90% confidence level upper limit on the branching ratio at 2.8x10(-11). We also report a new upper limit on the branching ratio for pi(0)-->m(+)e(-) of 3.8x10(-10) ( 90% C. L.).
Journal: Physical Review Letters