\phi\to\pi^0\eta\gamma and \phi\to\pi^0\pi^0\gamma decays and Mixing Between Low and High Mass Scalar Mesons

Abstract

Radiative decays \phi\to\eta\pi^0\gamma and \phi\to\pi^0\pi^0\gamma are studied assuming that these decays are caused through the intermediate a_0(980)\gamma and f_0(980)\gamma states, respectively. Fitting the experimental data of the \eta\pi^0 and \pi^0\pi^0 invariant mass spectrum in the decays \phi\to\eta\pi^0\gamma and \pi^0\pi^0\gamma, it is shown that the processes \phi\to a_0\gamma and \phi\to f_0\gamma are dominated by the K^+K^- loop interaction rather than the contact \phi a_0(f_0)\gamma one both for the non-derivative and derivative SPP coupling. The experimental data of \Gamma[\phi\to f_0\gamma]/\Gamma[\phi\to a_0\gamma] predicts that g_{f_0K\bar{K}}/g_{a_0K\bar{K}} \sim 2. Considering the effects of the mixing between low mass scalar qq\bar{q}\bar{q} states and high mass scalar q\bar{q} states to these coupling constants g_{f_0K\bar{K}} and g_{a_0K\bar{K}}, one suggests that the mixing is rather large.