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

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 studied by the chiral quark model, we extended this study to the S = -1 systems. All possible states with quantum numbers IJ(P) = 0(1/2)(-), 0(3/2)(-), 0(5/2)(-), 1(1/2)(-), 1(3/2)(-) and 1(5/2)(-) have been investigated. The calculation results shows that the newly observed state P-cs (4459) can be explained as Xi(c)(D) over bar* molecular state and the quantum numbers are 0(1/2)(-). In addition, we also find other molecular states Xi(c)(D) over bar, Xi(c)*(D) over bar and Xi(c)'(D) over bar*. It is worth mentioning that Xi(c)(D) over bar can form a two-peak structure from states in system 0(1/2)(-) and 0(3/2)(-). The decay width of all molecular states is givenwith the help of real scalingmethod. These hidden-charm pentaquark states is expected to be further verified in future experiments.