Γγ in the Snd Experiment at Vepp-2m
نویسندگان
چکیده
The η → πγγ decay was investigated by the SND detector at VEPP-2M ee collider in the reaction ee → φ → ηγ. Here we present the results and some details of this study. We report an upper limit (90% c.l.) Br(η → πγγ) < 8.4×10−4 as our final result. Our upper limit does not contradict the earlier measurement by GAMS spectrometer. To facilitate future studies a rather detailed review of the problem is also given.
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