The masses and decay widths of the S-wave cc bound states

In this work, we investigate possible bound states of the cc system in the Bethe-Salpeter formalism in the ladder and instantaneous approximations. By numerically solving the Bethe-Salpeter equation, we confirm the existence of cc bound states with quantum numbers J^PC=0^-+ and J^PC=1^--. We further investigate the partial decay widths of the cc bound states into NN, DD, DD^, D^^, , and KK. Our results indicate that the decay width of the cc bound state with J^PC=1^-- is much larger than that with J^PC=0^-+, and among their decay channels, the DD^ final state is the main decay mode. We suggest experiments to search for the cc bound states in the DD^ final state.