Measurement of ø-meson radiative decays at the storage ring VEPP-2M with the neutral detector

Abstract

Results of the first experiments with the Neutral Detector at the electron-positron storage ring VEPP-2M are presented. Branching ratios of the ø-meson radiative decays have been measured: B( ø→ ηγ)=(1.30±0.06)%, B( ø→ π 0 γ)=(0.130±0.013)%, their accuracy being several times higher than the world average. The width ratio is Γ(ø→ηγ) Γ(ø→π 0γ)=(10±1) . Using the abovementioned quantities, the ω− ø mixing angle θ v=(38.3±0.2) °, as well as the ratio between the effective magnetic moments of the s- and u-quarks, μ s μ u =(0.57±0.03) have been calculated.