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Study of the $ρ$ and $ω$ meson decays into pseudoscalar meson and $e^+e^-$ pair with the CMD-2 detector

2 Collaboration
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Abstract

Using 3.3 pb$^{-1}$ of data collected with the CMD-2 detector in the 720 -- 840 MeV c.m. energy range, the branching fraction of the conversion decay $ω\toπ^0e^+e^-$ has been measured: $\mathcal{B}(ω\toπ^0e^+e^-)=(8.19\pm0.71\pm0.62)\cdot10^{-4}$. The upper limits for the branching fractions of the following conversion decays have been obtained at the 90% confidence level: $\mathcal{B}(ρ\toπ^0e^+e^-)<1.6\cdot10^{-5}$, $\mathcal{B}(ρ\toηe^+e^-)<0.7\cdot10^{-5}$ and $\mathcal{B}(ω\toηe^+e^-)<1.1\cdot10^{-5}$.

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2 Collaboration. 2005-02-10. Study of the $ρ$ and $ω$ meson decays into pseudoscalar meson and $e^+e^-$ pair with the CMD-2 detector. https://doi.org/10.1016/j.physletb.2005.03.019

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