A global fit to determine the pseudoscalar mixing angle and the gluonium content of the η ’ meson
نویسندگان
چکیده
We update the values of the η-η mixing angle and of the η gluonium content by fitting our measurement Rφ = BR(φ → ηγ)/BR(φ → ηγ) together with several vector meson radiative decays to pseudoscalars (V → Pγ), pseudoscalar mesons radiative decays to vectors (P → V γ) and the η → γγ, π0 → γγ widths. From the fit we extract a gluonium fraction of Z2 G = 0.12±0.04, the pseudoscalar mixing angle ψP = (40.4±0.6)◦ and the φ−ω mixing angle ψV = (3.32 ± 0.09). Z2 G and ψP are fairly consistent with those previously published. We also evaluate the impact on the η gluonium content determination of future experimental improvements of the η branching ratios and decay width.
منابع مشابه
η-η ′ mixing from V → Pγ and J/ψ → V P decays ∗
The η-η pseudoscalar mixing angle and the gluonium content of the η meson are deduced from an updated phenomenological analysis of V → Pγ and J/ψ → V P decays. In absence of gluonium, the value of the mixing angle in the quark-flavour basis is found to be φP = (41.5 ± 1.2) from V → Pγ and φP = (40.5±2.4)◦ from J/ψ → V P . In presence of gluonium, the values for the mixing angle and the gluonic ...
متن کاملx / 06 12 02 9 v 2 1 5 D ec 2 00 6 Measurement of the pseudoscalar mixing angle and η ′ gluonium content with KLOE detector
We have measured the ratio Rφ = BR(φ → ηγ)/BR(φ → ηγ) by looking for the radiative decays φ → ηγ and φ → ηγ in the final states π+π− 7 γ’s and 7 γ’s respectively, in a sample of ∼ 1.3 · 109 φ mesons produced at the Frascati φfactory. We obtain Rφ = (4.77 ± 0.09stat ± 0.19sys) · 10−3 from which we derive BR(φ → ηγ) = (6.20 ± 0.11stat ± 0.25sys) · 10−5. In the hypothesis of no gluonium content we...
متن کاملx / 06 12 02 9 v 1 1 3 D ec 2 00 6 Measurement of the pseudoscalar mixing angle and η ′ gluonium content with KLOE detector
We have measured the ratio Rφ = BR(φ → ηγ)/BR(φ → ηγ) by looking for the radiative decays φ → ηγ and φ → ηγ in the final states π+π− 7 γ’s and 7 γ’s respectively, in a sample of ∼ 1.3 · 109 φ mesons produced at the Frascati φfactory. We obtain Rφ = (4.77 ± 0.09stat ± 0.19sys) · 10−3 from which we derive BR(φ → ηγ) = (6.20 ± 0.11stat ± 0.25sys) · 10−5. In the hypothesis of no gluonium content we...
متن کاملx / 06 12 02 9 v 3 1 8 Ju l 2 00 7 Measurement of the pseudoscalar mixing angle and η ′ gluonium content with the KLOE detector
We have measured the ratio Rφ = BR(φ → ηγ)/BR(φ → ηγ) by looking for the radiative decays φ → ηγ and φ → ηγ into the final states π+π−7γ and 7γ, respectively, in a sample of ∼1.4×109 φ mesons produced at the Frascati φ factory. We obtain Rφ = (4.77 ± 0.09stat ± 0.19syst)× 10−3, from which we derive BR(φ → ηγ) = (6.20±0.11stat±0.25syst)×10. Assuming the η has zero gluonium content, we extract th...
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