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arXiv · 1311.5005

Measurement of the ratio of the leptonic widths $Γ_{ee}/Γ_{μμ}$ for the $J/ψ$ meson

KEDR Collaboration·V. M. Aulchenko·E. M. Baldin·A. K. Barladyan·A. Yu. Barnyakov·M. Yu. Barnyakov·S. E. Baru·I. Yu. Basok·A. M. Batrakov·A. E. Blinov·V. E. Blinov·A. V. Bobrov·V. S. Bobrovnikov·A. V. Bogomyagkov·A. E. Bondar·A. R. Buzykaev·S. I. Eidelman·D. N. Grigoriev·V. R. Groshev·Yu. M. Glukhovchenko·V. V. Gulevich·D. V. Gusev·S. E. Karnaev·G. V. Karpov·S. V. Karpov·T. A. Kharlamova·V. A. Kiselev·V. V. Kolmogorov·S. A. Kononov·K. Yu. Kotov·E. A. Kravchenko·V. N. Kudryavtsev·V. F. Kulikov·G. Ya. Kurkin·E. A. Kuper·E. B. Levichev·D. A. Maksimov·V. M. Malyshev·A. L. Maslennikov·O. I. Meshkov·S. I. Mishnev·I. I. Morozov·N. Yu. Muchnoi·V. V. Neufeld·S. A. Nikitin·I. B. Nikolaev·I. N. Okunev·A. P. Onuchin·S. B. Oreshkin·I. O. Orlov·A. A. Osipov·S. V. Peleganchuk·S. G. Pivovarov·P. A. Piminov·V. V. Petrov·A. O. Poluektov·V. G. Prisekin·O. L. Rezanova·A. A. Ruban·V. K. Sandyrev·G. A. Savinov·A. G. Shamov·D. N. Shatilov·B. A. Shwartz·E. A. Simonov·S. V. Sinyatkin·A. N. Skrinsky·A. V. Sokolov·A. M. Sukharev·E. V. Starostina·A. A. Talyshev·V. A. Tayursky·V. I. Telnov·Yu. A. Tikhonov·K. Yu. Todyshev·G. M. Tumaikin·Yu. V. Usov·A. I. Vorobiov·A. N. Yushkov·V. N. Zhilich·V. V. Zhulanov·A. N. Zhuravlev
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Abstract

The ratio of the electron and muon widths of the $J/ψ$ meson has been measured using direct $J/ψ$ decays in the KEDR experiment at the VEPP-4M electron-positron collider. The result $Γ_{ee}(J/ψ)/Γ_{μμ}(J/ψ)=1.0022\pm0.0044\pm0.0048\ (0.65\%)$ is in good agreement with the lepton universality. The experience collected during this analysis will be used for a $J/ψ$ lepton width determination with up to 1% accuracy.

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KEDR Collaboration, V. M. Aulchenko, E. M. Baldin, A. K. Barladyan, A. Yu. Barnyakov, M. Yu. Barnyakov, S. E. Baru, I. Yu. Basok, A. M. Batrakov, A. E. Blinov, V. E. Blinov, A. V. Bobrov, V. S. Bobrovnikov, A. V. Bogomyagkov, A. E. Bondar, A. R. Buzykaev, S. I. Eidelman, D. N. Grigoriev, V. R. Groshev, Yu. M. Glukhovchenko, V. V. Gulevich, D. V. Gusev, S. E. Karnaev, G. V. Karpov, S. V. Karpov, T. A. Kharlamova, V. A. Kiselev, V. V. Kolmogorov, S. A. Kononov, K. Yu. Kotov, E. A. Kravchenko, V. N. Kudryavtsev, V. F. Kulikov, G. Ya. Kurkin, E. A. Kuper, E. B. Levichev, D. A. Maksimov, V. M. Malyshev, A. L. Maslennikov, O. I. Meshkov, S. I. Mishnev, I. I. Morozov, N. Yu. Muchnoi, V. V. Neufeld, S. A. Nikitin, I. B. Nikolaev, I. N. Okunev, A. P. Onuchin, S. B. Oreshkin, I. O. Orlov, A. A. Osipov, S. V. Peleganchuk, S. G. Pivovarov, P. A. Piminov, V. V. Petrov, A. O. Poluektov, V. G. Prisekin, O. L. Rezanova, A. A. Ruban, V. K. Sandyrev, G. A. Savinov, A. G. Shamov, D. N. Shatilov, B. A. Shwartz, E. A. Simonov, S. V. Sinyatkin, A. N. Skrinsky, A. V. Sokolov, A. M. Sukharev, E. V. Starostina, A. A. Talyshev, V. A. Tayursky, V. I. Telnov, Yu. A. Tikhonov, K. Yu. Todyshev, G. M. Tumaikin, Yu. V. Usov, A. I. Vorobiov, A. N. Yushkov, V. N. Zhilich, V. V. Zhulanov, A. N. Zhuravlev. 2014-02-17. Measurement of the ratio of the leptonic widths $Γ_{ee}/Γ_{μμ}$ for the $J/ψ$ meson. https://doi.org/10.1016/j.physletb.2014.02.046

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