title: First observation of the decay B --> J/psistraight phiK
abstract: We present the first observation of the decay B-->J/psistraight phiK. Using 9.6x10(6) B&Bmacr; meson pairs collected with the CLEO detector, we have observed ten fully reconstructed B-->J/psistraight phiK candidates, whereas the estimated background is 0.5+/-0.2 event. We obtain a branching fraction of B(B-->J/psistraight phiK) = (8. 8(+3.5)(-3.0)[stat]+/-1.3[syst])x10(-5). This is the first observed B meson decay requiring the creation of an additional s&smacr; quark pair.
authors.affiliation: Ohio State University, Columbus, Ohio 43210, USA.
authors.initials: JG
authors.lastname: Smith
authors.initials: JP
authors.lastname: Alexander
authors.initials: R
authors.lastname: Baker
authors.initials: C
authors.lastname: Bebek
authors.initials: BE
authors.lastname: Berger
authors.initials: K
authors.lastname: Berkelman
authors.initials: F
authors.lastname: Blanc
authors.initials: V
authors.lastname: Boisvert
authors.initials: DG
authors.lastname: Cassel
authors.initials: M
authors.lastname: Dickson
authors.initials: PS
authors.lastname: Drell
authors.initials: KM
authors.lastname: Ecklund
authors.initials: R
authors.lastname: Ehrlich
authors.initials: AD
authors.lastname: Foland
authors.initials: P
authors.lastname: Gaidarev
authors.initials: L
authors.lastname: Gibbons
authors.initials: B
authors.lastname: Gittelman
authors.initials: SW
authors.lastname: Gray
authors.initials: DL
authors.lastname: Hartill
authors.initials: BK
authors.lastname: Heltsley
authors.initials: PI
authors.lastname: Hopman
authors.initials: CD
authors.lastname: Jones
authors.initials: DL
authors.lastname: Kreinick
authors.initials: M
authors.lastname: Lohner
authors.initials: A
authors.lastname: Magerkurth
authors.initials: TO
authors.lastname: Meyer