The structure of pentaquarks ${\Omega }_c^0$ in the chiral quark model

Abstract

Recently, the experimental results of LHCb Collaboration suggested the existence of five new excited states of ${\Omega }_c^0$, ${\Omega }_c(3000{)}^0$, ${\Omega }_c(3050{)}^0$, ${\Omega }_c(3066{)}^0$, ${\Omega }_c(3090{)}^0$ and ${\Omega }_c(3119{)}^0$, the quantum numbers of these new particles are not determined now. To understand the nature of the states, a dynamical calculation of 5-quark systems with quantum numbers $I{J}^P=0(\frac{1}{2}{)}^{-}$, $0(\frac{3}{2}{)}^{-}$ and $0(\frac{5}{2}{)}^{-}$ is performed in the framework of chiral quark model with the help of gaussian expansion method. The results show the $\Xi -\bar{D}$, ${\Xi }_c\bar{K}$ and ${\Xi }_c^{\ast }\bar{K}$ are possible the candidates of these new particles. The distances between quark pairs suggest that the nature of pentaquark states.

Comments: 8 pages, 11 tables