In 2010, $\Lambda^*_{ c\bar{ c}}$ states were predicted as the strange number $S=-1$ partners of $N^*_{ c\bar{ c}}$, which are well known now as the $P_c$ states and observed experimentally by LHCb Collaboration. We analyze the decay behaviors of $\Lambda_{ c\bar{ c}}$ as S-wave hadronic molecules within the effective Lagrangian framework by a similar method, which has been applied on $P_c$ states successfully. With partial widths of possible decay channels calculated, we find that $\Lambda_{ c\bar{ c}}(4213)$ and $\Lambda_{ c\bar{ c}}(4403)$, which are formed as pseudoscalar meson baryon molecules, mainly decay to the $\eta_c \Lambda$ channel. For the two vector meson baryon molecule states, our results show that the total decay width with $J^P=\frac12^-$ is by one order of magnitude larger than that with $J^P=\frac32^-$. The decay patterns and relative decay ratios are very different for $\Lambda_{ c\bar{ c}}(4370)$ being a $D_s^{ * -} \Lambda_c^+$ or $\bar{ D}^{ *} \Xi_c$ molecule state. The main decay channels of $\Lambda_{ c\bar{ c}}(4550)$ are $\bar{ D}^{ (*)} \Xi^{ (*,\prime)}_c$ because of the pseudoscalar meson exchange mechanism. In addition, $\bar{ D}^{ *} \Xi_c$ is the dominant decay channel of $\Lambda_{ c\bar{ c}}(4490)$ which is assumed as a $\bar{ D} \Xi_c^{ *}$ bound state. These decay patterns of the $\Lambda^*_{ c\bar{ c}}$ states would provide a guidance for their future experimental searches and help us to understand their internal structures.
Categories: hep-ph