The observation by BESIII and LHCb of states with hidden charm and open strangeness (cc¯qs¯) presents new opportunities for the development of a global model of heavy-quark exotics. Here we extend the dynamical diquark model to encompass such states, using the same values of Hamiltonian parameters previously obtained from the nonstrange and hidden-strange sectors. The large mass splitting between Zcs(4000) and Zcs(4220) suggests substantial SU(3)flavor mixing between all JP=1+ states, while their average mass compared to that of other sectors offers a direct probe of flavor octet-singlet mixing among exotics. We also explore the inclusion of η-like exchanges within the states, and find their effects to be quite limited. In addition, using the same diquark-mass parameters, we find Pc(4312) and Pcs(4459) to fit well as corresponding nonstrange and open-strange pentaquarks.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)