$J^P$ Assignments of $\Lambda_c^+$ Baryons

The "good" diquark is employed to study $\Lambda_c^{+}$ baryons within a mass loaded flux tube model. The study indicates that all $\Lambda_c^{+}$ baryons candidates in the 2008 review by the Particle Data Group (PDG) are well described in the mass loaded flux tube model. The quantum numbers $J^P$ of these $\Lambda_c^{+}$ candidates are assigned. If $\Lambda_c(2765)^{+}$ is an orbitally excited $\Lambda^+_c$, it is likely the $J^P={3\over 2}^+$ one. If $\Lambda_c(2765)^+$ is an orbitally excited $\Sigma_c$, there ought to be another $J^P={3\over 2}^+$ $\Lambda^+_c$ with mass $\approx 2770$ MeV. In the model, there exists no $J^P={1\over 2}^+$ $\Lambda_c(\approx 2700)^+$ predicted in existing literature. $\Lambda_c(2940)^{+}$ is very possible the orbitally excited baryon with $J^P={5\over 2}^-$.