Toward establishing the low-lying $P$-wave $\Sigma_b$ states

Abstract

In the present work, we analyze the $P$-wave singly-heavy baryon spectrum belonging to $\mathbf{6}_F$ by combining the observations of the heavy baryon states, and restudy the strong decays of the $1P$ wave $\Sigma_b$ states within the $j$-$j$ coupling scheme using the chiral quark model. We obtain that: (i) the structure $\Sigma_b(6097)$ observed in the $\Lambda_b\pi$ final state may arise from the overlapping of $\Sigma_b|J^P=\frac{3}{2}^-,2\rangle$ and $\Sigma_b|J^P=\frac{5}{2}^-,2\rangle$. (ii) The broad structure $\Sigma_b(6072)$ observed in the $\Lambda_b\pi\pi$ final state may arise from the overlapping of $\Sigma_b|J^P=\frac{1}{2}^-,1\rangle$ and $\Sigma_b|J^P=\frac{3}{2}^-,1\rangle$. (iii) The missing state $\Sigma_b|J^P=\frac{1}{2}^-,0\rangle$ is most likely to be a narrow state with a width of $\Gamma\sim10$ MeV, and mainly decays into $\Lambda_b\pi$ channel.