eta→3π decays and octet scalar mesons

The η→3π decays are calculated in a meson-pole-dominance model, assuming the existence of an octet of scalar mesons. An SU(3)-symmetric interaction of a scalar meson and two pseudo-scalar mesons is considered. By virtue of this interaction, the η-π0 transition estimated from the ordinary SU(3) argument reproduces the decay rate Γ(η→π+π-π0) = 0.58 KeV, which is in very good agreement with the experimental value. The coupling constant between the scalar and pseudo-scalar mesons, evaluated from the Dalitz-plot slope of the η→π+π-π0 decay, is found consistent with the present experimental data on the decay widths of scalar mesons.