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arXiv · 0707.1601

Measurement of Prominent eta Decay Branching Fractions

A. Lopez·CLEO Collaboration
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Abstract

The decay psi(2S) --> eta J/psi is used to measure, for the first time, all prominent eta-meson branching fractions with the same experiment in the same dataset, thereby providing a consistent treatment of systematics across branching fractions. We present results for eta decays to gamma gamma, pi+pi-pi0, 3 pi0, pi+ pi- gamma, and e+ e- gamma, accounting for 99.9% of all eta decays. The precisions for several of the branching fractions and their ratios are improved. Two channels, pi+ pi- gamma and e+ e- gamma, show results that differ at the level of three standard deviations from those previously determined.

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A. Lopez, CLEO Collaboration. 2007-07-11. Measurement of Prominent eta Decay Branching Fractions. https://doi.org/10.1103/physrevlett.99.122001

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