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arXiv · hep-ex/9911036

New measurement of the rare decay $ϕ\to η' γ$ with CMD-2

CMD2 collaboration
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Abstract

A new measurement of the rare decay ϕ\to η' γperformed with the CMD-2 detector at Novosibirsk is described. Of the data sample corresponding to the integrated luminosity of 14.5 pb^{-1}, twenty one events have been selected in the mode η'\toπ^+π^-η, η\toγγ. The following branching ratio was obtained: B(ϕ\to η' γ) = (8.2^{+2.1}_{-1.9} \pm 1.1) 10^{-5}.

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CMD2 collaboration. 1999-11-24. New measurement of the rare decay $ϕ\to η' γ$ with CMD-2. https://doi.org/10.1016/s0370-2693(99)01475-6

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