We present a study of the inclusive photon spectra from 5.9 million J/ψ decays collected with the KEDR detector at the VEPP-4M e＋e collider. We measure the branching fraction of radiative decay J/ψ→ηcγ, ηc widt...We present a study of the inclusive photon spectra from 5.9 million J/ψ decays collected with the KEDR detector at the VEPP-4M e＋e collider. We measure the branching fraction of radiative decay J/ψ→ηcγ, ηc width and mass. Our preliminary results are： M（ηc） = 2979.4± 1.5 ± 1.9 MeV/c^2, Г（ηc） = 27.8±5.1 ±3.3 MeV, B（Jψ→ηcγ） = （2.34±0.15±0.40）%.展开更多
We report results of experiments performed with the KEDR detector at the VEPP-4M e^＋e^- collider. They include precise measurement of the D^0 and D^± meson masses, determination of the ψ（3770） resonance param...We report results of experiments performed with the KEDR detector at the VEPP-4M e^＋e^- collider. They include precise measurement of the D^0 and D^± meson masses, determination of the ψ（3770） resonance parameters, and a search for narrow resonances in e^＋e^- annihilation at center-of-mass energies between 1.85 and 3.1 GeV.展开更多
In an experiment with the Spherical Neutral Detector at VEPP-2M collider the cross section of the process e^＋e^- →π^＋π^-π^0π^0 was measured. At energies √s 〈 920 MeV this cross section was measured for the fi...In an experiment with the Spherical Neutral Detector at VEPP-2M collider the cross section of the process e^＋e^- →π^＋π^-π^0π^0 was measured. At energies √s 〈 920 MeV this cross section was measured for the first time. The energy dependence of the cross section is well discribed by the vector dominance model with contributions from p, p＇, p＂ mesons. The decay probability ρ→π^＋π^-π^0π^0 was found to be Bρ = （1.60±0.74±0.18） × 10^-5. The upper limit for the decay ω→π^＋π^-π^0π^0 was improved by two orders of magnitude compared to the previous measurements and is Bω 〈 2 × 10^-4 at 90% confidence level.展开更多
基金Supported by the Russian Foundation for Basic Research,grants 08-02-00258,08-02-00258RF Presidential Grant for Sc. Sch. NSh-5655.2008.2
文摘We present a study of the inclusive photon spectra from 5.9 million J/ψ decays collected with the KEDR detector at the VEPP-4M e＋e collider. We measure the branching fraction of radiative decay J/ψ→ηcγ, ηc width and mass. Our preliminary results are： M（ηc） = 2979.4± 1.5 ± 1.9 MeV/c^2, Г（ηc） = 27.8±5.1 ±3.3 MeV, B（Jψ→ηcγ） = （2.34±0.15±0.40）%.
基金Supported by Russian Foundation for Basic Research,Grant 04-02-16712,07-02-00816,07-02-01162RF Presidential Grant for Sc.Sch.NSh-5655.2008.2
文摘We report results of experiments performed with the KEDR detector at the VEPP-4M e^＋e^- collider. They include precise measurement of the D^0 and D^± meson masses, determination of the ψ（3770） resonance parameters, and a search for narrow resonances in e^＋e^- annihilation at center-of-mass energies between 1.85 and 3.1 GeV.
基金Supported by grant no.NSh 5655.2008.2 from the President of Russiasupported in part by RFBR grants 08-02-00328-a,8-02-00634-a,08-02-00660-a,07-02-00104-a
文摘In an experiment with the Spherical Neutral Detector at VEPP-2M collider the cross section of the process e^＋e^- →π^＋π^-π^0π^0 was measured. At energies √s 〈 920 MeV this cross section was measured for the first time. The energy dependence of the cross section is well discribed by the vector dominance model with contributions from p, p＇, p＂ mesons. The decay probability ρ→π^＋π^-π^0π^0 was found to be Bρ = （1.60±0.74±0.18） × 10^-5. The upper limit for the decay ω→π^＋π^-π^0π^0 was improved by two orders of magnitude compared to the previous measurements and is Bω 〈 2 × 10^-4 at 90% confidence level.
