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Upper Limit on the eta to gamma gamma gamma Branching Ratio with the KLOE Detector

The KLOE Collaboration·A. Aloisio
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Abstract

We have searched for the C-violating decay eta to gamma gamma gamma in a sample of ~ 18 million eta mesons produced in phi to eta gamma decays, collected with the KLOE detector at the Frascati phi-factory DAFNE. No signal is observed and we obtain the upper limit BR(eta to gamma gamma gamma) less equal than 1.6x10^(-5) at 90 % C.L.

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The KLOE Collaboration, A. Aloisio. 2004-06-08. Upper Limit on the eta to gamma gamma gamma Branching Ratio with the KLOE Detector. https://doi.org/10.1016/j.physletb.2004.04.012

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