Searching for eta to 3 gamma decay

The KLOE Collaboration; A. Aloisio

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arXiv · hep-ex/0307042

Searching for eta to 3 gamma decay

The KLOE Collaboration·A. Aloisio

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Abstract

Data collected by the KLOE experiment in years 2001/2002 for a total integrated luminosity of 410 pb$^{-1}$, corresponding to 17 million of produced $η$'s from the $Φ\to ηγ$ radiative decay, have been analyzed to look for the C-violating decay $η\toγγγ$. The signal is searched in events with 4 photons in the final state by using the spectrum of the most energetic photon. The background is evaluated from the data themself, doing a fifth degree polynomial fit outside the signal region, and extrapolating inside it. No signal has been observed and taking into account a selection efficiency $ε= 20.3 %$ we get from a likelihood fit Br$(η\toγγγ) \le 1.6\times10^{-5}$ at 95% CL. The procedure has a systematic ambiguity at the 35 % level.

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The KLOE Collaboration, A. Aloisio. 2003-07-17. Searching for eta to 3 gamma decay. https://arxiv.org/abs/hep-ex/0307042

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