Model for $J/\psi$ absorption in hadronic matter

Abstract

The cross sections for $J/\psi$ absorption by $\pi$ and $\rho$ mesons are studied in a meson-exchange model that includes not only pseudoscalar-pseudoscalar-vector-meson couplings but also three-vector-meson and four-point couplings. We find that they are much larger than in a previous study where only pseudoscalar-pseudoscalar-vector-meson couplings were considered. Including form factors at interaction vertices, the $J/\psi$ absorption cross sections ${\sigma }_{\pi \psi }$ and ${\sigma }_{\rho \psi }$ are found to have values on the order of 7 mb and 3 mb, respectively. Their thermal averages in hadronic matter at temperature T=150 MeV are, respectively, about 1 mb and 2 mb.

Comments: Appendix B added to show detailed comparisons, and meson matrices chosen to be traceless