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arXiv · 1509.00146

Structure of near-threshold quasi-bound states

Yuki Kamiya·Tetsuo Hyodo
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Abstract

We study the compositeness of near-threshold quasi-bound states in the framework of effective field theory. From the viewpoint of the low-energy universality, we revisit the model-independent relations between the structure of the bound state and the observables in the weak binding limit. The effective field theory is utilized to generalize the weak-binding relation of the stable bound states to unstable quasi-bound states with decay modes. We present the interpretation of the complex values of the compositeness for the unstable states. Combining the model-independent relation and the threshold observables extracted from the experimental data, we show that Lambda(1405) is dominated by the Kbar N molecular structure and that a_0(980) is dominated by the non-Kbar K component.

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Yuki Kamiya, Tetsuo Hyodo. 2016-05-22. Structure of near-threshold quasi-bound states. https://doi.org/10.1103/physrevc.93.035203

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