Strong decays of the ${\Lambda }_c(2910)$ and ${\Lambda }_c(2940)$ in the $N{D}^{\ast }$ molecular frame

Abstract

Stimulated by the observation of a new structure, named ${\Lambda }_c(2910)$, in the ${\Sigma }_c(2455{)}^{0,++}{\pi }^{+,-}$ decay channel from B meson decay process by the Belle Collaboration, and the similarity of the ${\Lambda }_c(2910)/{\Lambda }_c(2940)$ and $P_c$ states, we investigate the decay behavior of the ${\Lambda }_c(2910)$ and ${\Lambda }_c(2940)$ in the $N{D}^{\ast }$ molecular frame with the possible $J^P$ quantum numbers to be $1/2^{-}$ and $3/2^{-}$. We employ an effective Lagrangian approach to evaluate the partial widths of $ND$, ${\Sigma }_c\pi$ and ${\Sigma }_c^{\ast }\pi$ channels. The estimations in the present work indicate that the $J^P$ quantum numbers of ${\Lambda }_c(2910)$ and ${\Lambda }_c(2940)$ are preferred to be $1/2^{-}$ and $3/2^{-}$, respectively. From the present estimations, we also find the branching ratio of ${\Lambda }_c(3/2)\to {\Sigma }_c^{\ast }\pi$ is much larger than that of ${\Lambda }_c(1/2)\to {\Sigma }_c^{\ast }\pi$, thus ${\Sigma }_c^{\ast }\pi$ could be a good channel to distinguish the $J^P$ quantum numbers of ${\Lambda }_c(2910)$ and ${\Lambda }_c(2940)$. Therefore, we suggest to searching for the structure in ${\Sigma }_c^{\ast }\pi$ invariant mass distribution in Belle $⨿$.

Comments: 12 pages, 13 figures, 3 tables, accepted for publication in PRD