Novel coupled channel framework connecting quark model and lattice QCD: an investigation on near-threshold $D_s$ states

TL;DR

This paper introduces a new coupled channel framework that combines quark models and lattice QCD to analyze near-threshold $D_s$ states, revealing their internal structure and level crossing behaviors.

Contribution

It develops a novel Hamiltonian effective field theory framework that connects quark model states with lattice QCD energy levels for near-threshold resonances.

Findings

The physical $D_s$ states are mixtures of quark model cores and meson components.

The model reproduces level crossing phenomena observed in lattice QCD.

Bare quark-antiquark states are predominantly pure in heavy-quark spin basis.

Abstract

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 $D_s$. The quark model, the quark-pair-creation mechanism and $D^{(*)}K$ interaction are incorporated into the Hamiltonian effective field theory. The bare $1^+$ $c\bar s$ states are almost purely given by the states with heavy-quark spin bases. The physical $D^*_{s0}(2317)$ and $D^*_{s1}(2460)$ are the mixtures of bare $c\bar s$ core and $D^{(*)}K$ component, while the $D^*_{s1}(2536)$ and $D^*_{s2}(2573)$ are almost dominated by bare $c\bar{s}$. Furthermore, our model reproduces the clear level crossing of the $D^*_{s1}(2536)$ with the scattering state at a finite volume.