Unitarity and partial width forφ→3π

Abstract

It is shown that absorptive contributions to $g_{\phi \rho \pi }$ coming from $\phi \to K\overline{K}\to 3\pi$ may account for the observed magnitude of $\Gamma (\phi \to 3\pi )$. Two complementary calculations, one based on the Gell-Mann-Sharp-Wagner model and the other based on partial-wave unitarity, are presented. It is argued that $\psi \mathrm{}\left(3105\right)\mathrm{}$ and $\psi \mathrm{}\left(3695\right)\mathrm{}$ are especially narrow since similar absorptive corrections are absent.