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arXiv · hep-ex/0012039

Study of conversion decays phi->etae+e-, eta->e+e-g and eta->pi+pi-e+e- at CMD-2

2 collaboration
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Abstract

Using 15.1 pb^{-1} of data collected by CMD-2 in the phi-meson energy range, the branching ratios of the following conversion decays have been measured: B(ϕ\toηe^+e^-) = (1.14\pm0.10\pm0.06)\cdot10^{-4}, B(η\to e^+e^-γ) = (7.10\pm0.64\pm0.46)\cdot10^{-3}, B(η\toπ^+π^-e^+e^-) = (3.7^{+2.5}_{-1.8}\pm0.3)\cdot10^{-4}. The upper limits for the following rare conversion decays have been obtained at the 90% confidence level: B(ϕ\toημ^+μ^-) < 9.4\cdot10^{-6}, B(η\to e^+e^-e^+e^-) < 6.9\cdot10^{-5}.

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2 collaboration. 2000-12-16. Study of conversion decays phi->etae+e-, eta->e+e-g and eta->pi+pi-e+e- at CMD-2. https://doi.org/10.1016/s0370-2693(01)00123-x

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