Novel coupled channel framework connecting the quark model and lattice QCD for the near-threshold states

Yang, Z.*; Wang, G.-J.*; Wu, J.-J.*; Oka, Makoto   ; Zhu, S.-L.*

A novel framework is proposed to extract near-threshold resonant states from finite-volume energy levels of lattice QCD and is applied to elucidate structures of the positive parity . The quark model, the quark-pair-creation mechanism and interaction are incorporated into the Hamiltonian effective field theory. The bare states are almost purely given by the states with heavy-quark spin bases. The physical and are the mixtures of bare core and component, while the and are almost dominated by bare . Furthermore, our model well reproduce the clear level crossing of the with the scattering state at a finite volume.