Cross Sections for the Dissociation of J/psi and psi' by pi and rho at low energies

Abstract

Using the quark-interchange model of Barnes and Swanson, we evaluate the dissociation cross sections for $J/\psi$ and $\psi'$ by $\pi$ and $\rho$ at low collision energies. In collisions with $\pi$ mesons near threshold the $\pi + J/\psi$ dissociation cross section is predicted to be small, but the $\pi +\psi'$ cross section is found to be quite large, in qualitative agreement with experimental data on $J/\psi$ and $\psi'$ production in high-energy heavy-ion collisions. The $\rho + J/\psi$ and $\rho + \psi'$ dissociation cross sections are both predicted to be large numerically and are divergent near threshold. These $\rho + J/\psi$ and $\rho + \psi'$ cross sections show considerable sensitivity to the mass of the $\rho$ meson if it is off energy shell.