title: Improved limit on the rate of the decay K+ --> pi(+)&mgr;(+)e(-)
abstract: We report results of a search for the lepton-family number violating decay K+-->pi(+)&mgr;(+)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)-->&mgr;(+)e(-) of 3.8x10(-10) ( 90% C. L.).
authors.affiliation: Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260 and Physics Department, Yale University, New Haven, Connecticut 06511, USA.
authors.initials: R
authors.lastname: Appel
authors.initials: GS
authors.lastname: Atoyan
authors.initials: B
authors.lastname: Bassalleck
authors.initials: DR
authors.lastname: Bergman
authors.initials: DN
authors.lastname: Brown
authors.initials: N
authors.lastname: Cheung
authors.initials: S
authors.lastname: Dhawan
authors.initials: H
authors.lastname: Do
authors.initials: J
authors.lastname: Egger
authors.initials: S
authors.lastname: Eilerts
authors.initials: C
authors.lastname: Felder
authors.initials: H
authors.lastname: Fischer
authors.initials: M
authors.lastname: Gach
authors.initials: W
authors.lastname: Herold
authors.initials: VV
authors.lastname: Issakov
authors.initials: H
authors.lastname: Kaspar
authors.initials: DE
authors.lastname: Kraus
authors.initials: DM
authors.lastname: Lazarus
authors.initials: L
authors.lastname: Leipuner
authors.initials: P
authors.lastname: Lichard
authors.initials: J
authors.lastname: Lowe
authors.initials: J
authors.lastname: Lozano
authors.initials: H
authors.lastname: Ma
authors.initials: W
authors.lastname: Majid
authors.initials: W
authors.lastname: Menzel
authors.initials: S
authors.lastname: Pislak