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arXiv · 2512.20155

Internal structure of near-threshold states using compositeness

Tomona Kinugawa·Tetsuo Hyodo
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Abstract

Understanding the internal structure of near-threshold states is essential for revealing the nature of exotic hadrons. Motivated by this challenge, we discuss the clustering structures of near-threshold $s$-wave eigenstates using the compositeness, which characterizes the clustering nature of the states. We show that shallow bound states usually possess cluster-dominant structures, while near-threshold narrow resonances are non-cluster-dominant. Through this study, we establish a theoretical foundation for the threshold energy rule, which has been known empirically.

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Tomona Kinugawa, Tetsuo Hyodo. 2025-12-23. Internal structure of near-threshold states using compositeness. https://arxiv.org/abs/2512.20155

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