Strong decay of $\Lambda_c(2940)$ as a $2P$ state in the $\Lambda_c$ family

TL;DR

This paper investigates the nature of the $ ext{Lambda}_c(2940)$ baryon, proposing it as a $2P$ state with specific quantum numbers, and analyzes its decay behavior using the $^3P_0$ model to match experimental data.

Contribution

The study assigns $ ext{Lambda}_c(2940)$ as a $2P$ state and calculates its decay widths, providing a theoretical interpretation consistent with experimental observations.

Findings

The total decay widths for $J^P=1/2^-$ and $3/2^-$ states are 16.27 MeV and 25.39 MeV.

The $J^P=3/2^-$ assignment better matches experimental data.

Other $ ext{Sigma}_c(2P)$ states are predicted to be narrow and observable in future experiments.

Abstract

Considering the mass, parity and $D^0 p$ decay mode, we tentatively assign the $\Lambda_c(2940)$ as the $P-$wave states with one radial excitation. Then, via studying the strong decay behavior of the $\Lambda_c(2940)$ within the $^3P_0$ model, we obtain that the total decay widths of the $\Lambda_{c1}(\frac{1}{2}^-,2P)$ and $\Lambda_{c1}(\frac{3}{2}^-,2P)$ states are 16.27 MeV and 25.39 MeV, respectively. Compared with the experimental total width $27.7^{+8.2}_{-6.0}\pm0.9^{+5.2}_{-10.4}~\rm{MeV}$ measured by LHCb Collaboration, both assignments are allowed, and the $J^P=\frac{3}{2}^-$ assignment is more favorable. Other $\lambda-$mode $\Sigma_c(2P)$ states are also investigated, which are most likely to be narrow states and have good potential to be observed in future experiments.