$J/\psi$ reaction mechanisms and suppression in the nuclear medium

Understand

Recent studies of the interaction of vector mesons with nuclei make possible and opportune the study of the interaction of the $J/\psi$ with nuclei and the investigation of the origin of the $J/\psi$ suppression in its propagation thorough a nuclear medium.

• We observe that the transition of $J/\psi N$ to $VN$ with $V$ being a light vector, $\rho, \omega,\phi$, together with the inelastic channels, $J/\psi N \to \bar D \Lambda_c$ and $J/\psi N \to \bar D \Sigma_c$ leads to a particular shape of the inelastic cross section.
• Analogously, we consider the mechanisms where the exchanged $D$ collides with a nucleon and gives $\pi \Lambda_c$ or $\pi \Sigma_c$.
• The cross section has a peak around $\sqrt s=4415$ MeV, where the $J/\psi N$ couples to a resonance predicted recently.