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arXiv · 0806.0671

Observation of J/psi --> 3 gamma

CLEO Collaboration·G. S. Adams
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Abstract

We report the first observation of the decay J/psi --> 3 gamma. The signal has a statistical significance of 6 sigma and corresponds to a branching fraction of B(J/psi --> 3 gamma) = (1.2 +- 0.3 +- 0.2) x 10^-5, in which the errors are statistical and systematic, respectively. The measurement uses psi(2S) --> pi+ pi- J/psi events acquired with the CLEO-c detector operating at the CESR e+e- collider.

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CLEO Collaboration, G. S. Adams. 2008-06-04. Observation of J/psi --> 3 gamma. https://doi.org/10.1103/physrevlett.101.101801

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