Nature of $K^{\ast }(1680)$ and $q\bar{q}$-hybrid mixing as the SU(3) partner of ${\eta }_1(1855)$ in the strange sector

We presents an investigation of the $K^{\ast }(1680)$ state in its strong decays into two-body finial states within the flux-tube model and quark pair creation model. Since the charge conjugation parity is not conserved in the strange sector, the conventional $q\bar{q}$ states of $J^{P(C)}=1^{-(-)}$ can mix with the lowest hybrid states with $J^{P(C)}=1^{-(+)}$. Our analysis of the $K^{\ast }(1680)$ two-body strong decays indicates that the decay pattern of $K^{\ast }(1680)$ cannot be explained by the conventional $q\bar{q}$ scenario. Meanwhile, strong evidence shows the $q\bar{q}$-hybrid mixing mechanism in the strange sector. The phenomenological consequences of such a mixing are also discussed. Our study can provide a guidance for the future search for hybrid multiplets in experiment at BESIII, LHCb, and Belle-II.