# Possible hadronic molecular states composed of $S$-wave heavy-light mesons

## TL;DR

This study systematically investigates potential molecular states formed by S-wave heavy-light mesons, considering mixing effects, and suggests the X(3872) as a molecular state while predicting other possible molecules for experimental search.

## Contribution

It explicitly includes S-D mixing and $\eta-\eta^{\prime}$ mixing in the analysis, providing new insights into the nature of certain exotic mesons.

## Key findings

- X(3872) likely a Dar{D}* molecular state
- Zc(3900)/Zc(4020) and Zb(10610)/Zb(10650) are not molecular states
- Predicted new molecular states for future experimental verification

## Abstract

We perform a systematical study of possible molecular states composed of the $S$ wave heavy light mesons, where the $S-D$ mixing and {$\eta-\eta^{\prime}$ mixing} are explicitly included. Our calculation indicates that the observed $X(3872)$ could be a loosely shallow molecular state composed of $D\bar{D}^\ast +h.c$, while neither $Z_c(3900)/Z_c(4020)$ nor $Z_b(10610)/Z_b(10650)$ is supported to be a molecule. Some observed possible molecular states are predicted, which could be searched for by further experimental measurements.