Effect of the $K\overline{K}$ and $\eta \eta$ channels and interference phenomena in the two-pion and $K\overline{K}$ transitions of charmonia and bottomonia

Abstract

It is shown that the basic shape of dipion and $K\overline{K}$ mass spectra in decays $J/\psi \to \varphi (\pi \pi ,K\overline{K})$, $\psi (2S)\to J/\psi \pi \pi$, $Y(4260)\to J/\varphi \pi \pi$ and in the two-pion transitions of bottomonia states are explained by an unified mechanism based on the contribution of the $\pi \pi$, $K\overline{K}$ and $\eta \eta$ coupled channels including their interference. The role of the individual $f_0$ resonances in making up the shape of the dipion mass distributions in the charmonia and bottomonia decays is considered.

Comments: 13 pages, 9 figures