Strong and radiative decays of the low-lying $D$-wave singly heavy baryons

Abstract

The strong and radiative decays of the low-lying $\lambda$-mode $D$-wave $\Lambda_{c(b)}$, $\Sigma_{c(b)}$, $\Xi_{c(b)}$, $\Xi_{c(b)}'$, and $\Omega_{c(b)}$ baryons are studied in a constituent quark model. Our calculation shows the following: (i) The missing $\lambda$-mode $D$-wave $\Omega_{c(b)}$, $\Lambda_{b}$, and $\Xi_{b}$ baryons have a relatively narrow decay width of a few MeV or a few tens of MeV and their dominant strong and radiative decay channels can be ideal for searching for their signals in future experiments. (ii) The $\lambda$-mode $1D$-wave excitations in the $\Sigma_{c(b)}$ and $\Xi_{c(b)}'$ families appear to have a relatively broad width of $\sim 50-200$ MeV.Most of the $1D$-wave states have large decay rates into the $1P$-wave heavy baryons via the pionic or kaonic strong decay processes, which should be taken seriously in future observations. (iii) Both $\Lambda_c(2860)$ and $\Xi_c(3050)$ seem to favor the $J^P=3/2^+$ excitation $|^2D_{\lambda\lambda} \frac{3}{2}^+ \rangle$ of $\bar{\mathbf{3}}_F$, while both $\Lambda_c(2880)$ and $\Xi_c(3080)$ may be assigned as the $J^P=5/2^+$ excitation $|^2D_{\lambda\lambda} \frac{5}{2}^+ \rangle$ of $\bar{\mathbf{3}}_F$. The nature of $\Xi_c(3050)$ and $\Xi_c(3080)$ could be tested by the radiative transitions $\Xi_c(3055)^0\to \Xi_c(2790)^0 \gamma$ and $\Xi_c(3080)^0 \to \Xi_c(2815)^0 \gamma$, respectively.