Measurement of J/psi -%26gt; gamma eta(c) decay rate and eta(c) parameters at KEDR

作者：Anashin V V; Aulchenko V M; Baldin E M; Barladyan A K; Barnyakov A Yu; Barnyakov M Yu; Baru S E; Basok I Yu; Bedny I V; Blinov A E; Blinov V E; Bobrov A V; Bobrovnikov V S; Bogomyagkov A V; Bondar A E; Buzykaev A R; Eidelman S I^*; Glukhovchenko Yu M; Gulevich V V; Gusev D V; Karnaev S E; Karpov G V; Karpov S V; Kharlamova T A; Kiselev V A; Kononov S A; Kotov K Yu; Kravchenko E A; Kulikov V F; Kurkin G Ya

来源：Physics Letters B, 2014, 738: 391-396.

DOI：10.1016/j.physletb.2014.09.064

• Charmonium
• Radiative decays

Using the inclusive photon spectrum based on a data sample collected at the J/psi peak with the KEDR detector at the VEPP-4M e(+)e(-) collider, wemeasured the rate of the radiative decay J/psi -%26gt; gamma eta(c) as well as eta(c) mass and width. Taking into account an asymmetric photon lineshape we obtained Gamma(0)(gamma eta c) = 2.98 +/- 0.18(-0.33)(+0.15) keV, M-eta c = 2983.5 +/- 1.4(-3.6)(+1.6) MeV/c(2), Gamma(eta c) = 27.2 +/- 3.1(-2.6)(+5.4) MeV.

• 出版日期2014-11-10