Analysis of the strong coupling constants ga0ηπ0 and ga0η′π0 with light-cone QCD sum rules

In this article, we take the point of view that the light scalar meson a0(980) is a qq̄ state, and calculate the strong coupling constants ga0ηπ0 and ga0η′π0 with the light-cone QCD sum rules. The strong coupling constant ga0ηπ0 is a basic parameter in studying the radiative decay φ(1020) → a0(980)γ → ηπ0γ. The lower bound of the decay width Γa0→ηπ0 = 127 +120 −53 MeV is compatible with the experimental data for the total decay width Γa0(980) = (50−100)MeV, while the upper bound is too large, the scalar meson a0(980) can’t be a pure qq̄ state. We give possible explanation for the discrepancy between the theoretical calculation and the experimental data. PACS numbers: 12.38.Lg; 13.25.Jx; 14.40.Cs