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arXiv · 1011.0885

Evidence for psi' decays into gamma pi^0 and gamma eta

The BESIII Collaboration
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Abstract

The decays psi'->gamma pi^0, gamma eta and gamma eta' are studied using data collected with the BESIII detector at the BEPCII e^+e^- collider. Processes psi'->gamma pi^0 and psi'->gamma eta are observed for the first time with signal significances of 4.6 sigma and 4.3 sigma, respectively. The branching fractions are determined to be: B(psi'->gamma pi^0)=(1.58+-0.40+-0.13)x10^{-6}, B(psi'->gamma eta)=(1.38+-0.48+-0.09)x10^{-6}, and B(psi'->gamma eta')=(126+-3+-8) x 10^{-6}, where the first errors are statistical and the second ones systematic.

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The BESIII Collaboration. 2010-11-03. Evidence for psi' decays into gamma pi^0 and gamma eta. https://doi.org/10.1103/physrevlett.105.261801

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