The masses and decay widths of the $S$-wave $\Lambda_c\bar{\Lambda}_c$ bound states

Abstract

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