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 $6_F$ 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 ${\Sigma }_b|J^P={\frac{3}{2}}^{-},2⟩$ and ${\Sigma }_b|J^P={\frac{5}{2}}^{-},2⟩$. (ii) The broad structure ${\Sigma }_b(6072)$ observed in the ${\Lambda }_b\pi \pi$ final state may arise from the overlapping of ${\Sigma }_b|J^P={\frac{1}{2}}^{-},1⟩$ and ${\Sigma }_b|J^P={\frac{3}{2}}^{-},1⟩$. (iii) The missing state ${\Sigma }_b|J^P={\frac{1}{2}}^{-},0⟩$ is most likely to be a narrow state with a width of $\Gamma \sim 10$ MeV, and mainly decays into ${\Lambda }_b\pi$ channel.

Comments: 7 pages, 2 figures