Investigation of hidden-charm pentaquarks with strangeness $S=-1$

TL;DR

This paper uses a chiral quark model to analyze hidden-charm pentaquarks with strangeness S=-1, explaining the recently observed P_{cs}(4459) as a molecular state and predicting additional possible molecular states for future experimental verification.

Contribution

The study extends previous predictions to S=-1 systems, identifying the P_{cs}(4459) as a $\Xi_c ar{D}^*$ molecular state with specific quantum numbers and predicting other molecular states.

Findings

P_{cs}(4459) explained as $\Xi_c ar{D}^*$ molecule with $0(rac{1}{2})^-$

Predicted additional molecular states $\Xi_c ar{D}$, $\Xi_c^* ar{D}$, $\Xi_c' ar{D}^*$

Two-peak structure possible from $\Xi_c ar{D}^*$ states in different quantum configurations

Abstract

Recently, a new hidden-charm pentaquark state $P_{cs}(4459)$ was reported by the LHCb Collaboration. Stimulated by the fact that all hidden-charm pentaquark states in $S=0$ systems were successfully predicted by our chiral quark model, we extended this study to the $S=-1$ systems. All possible quantum numbers $IJ^P=0(\frac{1}{2})^-$, $0(\frac{3}{2})^-$, $0(\frac{5}{2})^-$, $1(\frac{1}{2})^-$, $1(\frac{3}{2})^-$ and $1(\frac{5}{2})^-$ have been investigated. The calculation results shows that the newly observed state $P_{cs}(4459)$ can be explained as $\Xi_c \bar{D}^*$ molecular state and the quantum number is $0(\frac{1}{2})^-$. In addition, we also find other molecular states $\Xi_c \bar{D}$, $\Xi_c^* \bar{D}$ and $\Xi_c' \bar{D}^*$. It is worth mentioning that $\Xi_c \bar{D}^*$ can form a two-peak structure from states in system $0(\frac{1}{2})^-$ and $0(\frac{3}{2})^-$. The decay width of all molecular states is given with the help of real scaling method. These hidden-charm pentaquark states is expected to be further verified in future experiments.