Analysis of $\Omega (2012)$ as a molecule in the chiral quark model

Abstract

Inspired by the updated information on $\Omega (2012)$ by the Belle Collaboration, we conduct a study of all possible $S$-wave pentaquark systems with quark contents $sssq\bar{q},q=u,d$ in a chiral quark model with the help of Gaussian expansion method. Channel coupling is also considered. The real-scaling method (stabilization method) is employed to identify and check the bound states and the genuine resonances. In addition, the decay widths of all resonances are given. The results show that $\Omega (2012)$ can be interpreted as a ${\Xi }^{\ast }K$ molecular state with quantum number of $I{J}^P=0(\frac{3}{2}{)}^{-}$. Other resonances are obtained: ${\Xi }^{\ast }{K}^{\ast }$ with $I{J}^P=0(\frac{1}{2}{)}^{-}$ and$0(\frac{3}{2}{)}^{-}$, $\Omega \pi$ with $I{J}^P=1(\frac{3}{2}{)}^{-}$. These pentaquark states is expected to be further verified in future experiments.

Comments: 10 pages, 5 figures. arXiv admin note: text overlap with arXiv:2109.09972