Compositeness of Hadrons and Near-Threshold Dynamics

TL;DR

This paper reviews recent advances in understanding hadron resonance structures, emphasizing the model-independent determination of their compositeness and applying these insights to various hadrons.

Contribution

It introduces a framework for assessing the compositeness of hadron resonances that reduces model dependence and applies this to multiple hadronic states.

Findings

Near-threshold states have structure determined independently of models

The compositeness of various hadrons can be reliably assessed

The approach clarifies the nature of hadron resonances

Abstract

We present the recent developments in the studies of the structure of hadron resonances, focusing on the compositeness in terms of the hadronic degrees of freedom. We discuss the model dependence of the compositeness, and show that the structure of the near-threshold bound states and resonances is model-independently determined. The applications to various hadrons are summarized.