Measurement of psi(3770) parameters

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; Beloborodova O L; Blinov A E; Blinov V E; Bobrov A V; Bobrovnikov V S; Bogomyagkov A V; Bondar A E; Buzykaev A R; Eidelman S I; Grigoriev D N; Glukhovchenko Yu M; Gulevich V V; Gusev D V; Karnaev S E; Karpov G V; Karpov S V; Kharlamova T A; Kiselev V A; Kolmogorov V V; Kononov S A; Kotov K Yu

来源：Physics Letters B, 2012, 711(3-4): 292-300.

DOI：10.1016/j.physletb.2012.04.019

We report the final results of a study of the psi(3770) meson using a data sample collected with the KEDR detector at the VEPP-4M electron-positron collider. The data analysis takes into account interference between the resonant and nonresonant D (D) over bar production, where the latter is related to the nonresonant part of the energy-dependent form factor F-D. The vector dominance approach and several empirical parameterizations have been tried for the nonresonant F-D(NR)(S). %26lt;br%26gt;Our results for the mass and total width of psi(3770) are %26lt;br%26gt;M = 3779.2(-1.7 -0.7 -0.3)(+1.8) (+0.5) (+0.3) MeV, %26lt;br%26gt;Gamma = 24.9(-4.0 -0.6 -0.9)(+4.6) (+0.5) (+0.2) MeV, %26lt;br%26gt;where the first, second and third uncertainties are statistical, systematic and model, respectively. For the electron partial width two possible solutions have been found: %26lt;br%26gt;(1) Gamma(ee) = 154(-58 -9 -25)(+79 + 17 + 13) eV. %26lt;br%26gt;(2) Gamma(ee) = 414(-80 -26 -10)(+72 +24 +90) eV. %26lt;br%26gt;Our statistics are insufficient to prefer one solution to another. The Solution (2) mitigates the problem of non-D (D) over bar decays but is disfavored by potential models. %26lt;br%26gt;It is shown that taking into account the resonance-continuum interference in the near-threshold region affects resonance parameters, thus the results presented cannot be directly compared with the corresponding PDG values obtained ignoring this effect.

• 出版日期2012-5-15