title: Measurement of structure-dependent K+ --> &mgr;(+)nu(&mgr;)gamma decay
abstract: We report the first measurement of a structure-dependent component in the decay K+-->&mgr;(+)nu(&mgr;)gamma. Using the kinematic region where the muon kinetic energy is greater than 137 MeV and the photon energy is greater than 90 MeV, we find that the absolute value of the sum of the vector and axial-vector form factors is |F(V)+F(A)| = 0.165+/-0.007+/-0.011. This corresponds to a branching ratio of B(SD+) = (1.33+/-0.12+/-0.18)x10(-5). We also set the limit -0. 04<F(V)-F(A)<0.24 at 90% C.L.
authors.affiliation: Brookhaven National Laboratory, Upton, New York 11973, USA.
authors.initials: S
authors.lastname: Adler
authors.initials: MS
authors.lastname: Atiya
authors.initials: IH
authors.lastname: Chiang
authors.initials: MV
authors.lastname: Diwan
authors.initials: JS
authors.lastname: Frank
authors.initials: JS
authors.lastname: Haggerty
authors.initials: SH
authors.lastname: Kettell
authors.initials: TF
authors.lastname: Kycia
authors.initials: KK
authors.lastname: Li
authors.initials: LS
authors.lastname: Littenberg
authors.initials: A
authors.lastname: Sambamurti
authors.initials: A
authors.lastname: Stevens
authors.initials: RC
authors.lastname: Strand
authors.initials: C
authors.lastname: Witzig
authors.initials: TK
authors.lastname: Komatsubara
authors.initials: M
authors.lastname: Kuriki
authors.initials: N
authors.lastname: Muramatsu
authors.initials: S
authors.lastname: Sugimoto
authors.initials: T
authors.lastname: Inagaki
authors.initials: S
authors.lastname: Kabe
authors.initials: M
authors.lastname: Kobayashi
authors.initials: Y
authors.lastname: Kuno
authors.initials: T
authors.lastname: Sato
authors.initials: T
authors.lastname: Shinkawa
authors.initials: Y
authors.lastname: Yoshimura
authors.initials: Y
authors.lastname: Kishi