Physics Letters B (2018-06-01)

Measurement of Γee×Bμμ for ψ(2S) meson

  • V.V. Anashin,
  • O.V. Anchugov,
  • V.M. Aulchenko,
  • E.M. Baldin,
  • G.N. Baranov,
  • A.K. Barladyan,
  • A.Yu. Barnyakov,
  • M.Yu. Barnyakov,
  • S.E. Baru,
  • I.Yu. Basok,
  • A.M. Batrakov,
  • E.A. Bekhtenev,
  • A.E. Blinov,
  • V.E. Blinov,
  • A.V. Bobrov,
  • V.S. Bobrovnikov,
  • A.V. Bogomyagkov,
  • A.E. Bondar,
  • A.R. Buzykaev,
  • P.B. Cheblakov,
  • V.L. Dorohov,
  • S.I. Eidelman,
  • D.N. Grigoriev,
  • S.A. Glukhov,
  • S.E. Karnaev,
  • G.V. Karpov,
  • S.V. Karpov,
  • K.Yu. Karukina,
  • D.P. Kashtankin,
  • T.A. Kharlamova,
  • V.A. Kiselev,
  • V.V. Kolmogorov,
  • S.A. Kononov,
  • K.Yu. Kotov,
  • A.A. Krasnov,
  • E.A. Kravchenko,
  • V.N. Kudryavtsev,
  • V.F. Kulikov,
  • G.Ya. Kurkin,
  • I.A. Kuyanov,
  • E.A. Kuper,
  • E.B. Levichev,
  • D.A. Maksimov,
  • V.M. Malyshev,
  • A.L. Maslennikov,
  • O.I. Meshkov,
  • S.I. Mishnev,
  • I.A. Morozov,
  • I.I. Morozov,
  • N.Yu. Muchnoi,
  • S.A. Nikitin,
  • I.B. Nikolaev,
  • I.N. Okunev,
  • A.P. Onuchin,
  • S.B. Oreshkin,
  • A.A. Osipov,
  • I.V. Ovtin,
  • S.V. Peleganchuk,
  • S.G. Pivovarov,
  • P.A. Piminov,
  • V.V. Petrov,
  • V.G. Prisekin,
  • O.L. Rezanova,
  • A.A. Ruban,
  • G.A. Savinov,
  • A.G. Shamov,
  • D.N. Shatilov,
  • D.A. Shvedov,
  • B.A. Shwartz,
  • E.A. Simonov,
  • S.V. Sinyatkin,
  • A.N. Skrinsky,
  • A.V. Sokolov,
  • D.P. Sukhanov,
  • A.M. Sukharev,
  • E.V. Starostina,
  • A.A. Talyshev,
  • V.A. Tayursky,
  • V.I. Telnov,
  • Yu.A. Tikhonov,
  • K.Yu. Todyshev,
  • A.G. Tribendis,
  • G.M. Tumaikin,
  • Yu.V. Usov,
  • A.I. Vorobiov,
  • V.N. Zhilich,
  • A.A. Zhukov,
  • V.V. Zhulanov,
  • A.N. Zhuravlev

Journal volume & issue
Vol. 781
pp. 174 – 181

Abstract

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The product of the electronic width of the ψ(2S) meson and the branching fraction of its decay to the muon pair was measured in the e+e−→ψ(2S)→μ+μ− process using nine data sets corresponding to an integrated luminosity of about 6.5 pb−1 collected with the KEDR detector at the VEPP-4M electron–positron collider:Γee×Bμμ=19.3±0.3±0.5eV. Adding the previous KEDR results on hadronic and leptonic channels, the values of the ψ(2S) electronic width were obtained under two assumptions: either with the assumption of lepton universalityΓee=2.279±0.015±0.042keV or without it, summing up hadronic and three independent leptonic channelsΓee=2.282±0.015±0.042keV. Keywords: ψ(2S) meson, Leptonic width, Branching fraction