Quark content of f0(980) from the decay ratios into ππ, KK̄ and γγ

The quark content of the meson f0(980) is determined on the basis of coupling constants of the decays f0(980)→ππ, KK̄ and γγ. The combined analysis has been carried out with the Flatté formula for the ratio of coupling constants gKK̄/gππ found by fitting to data for the decays f0(980)→ππ, KK̄ and transition form factor f0(980)→qq̄→γγ, which is determined from the data on γγ partial width. For the flavour wave function of f0(980) written as nn̄cosφ+ss̄sinφ, two solutions appear: 1) φ≃55° and 2) φ≃−43°.