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
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.
