[Submitted on 1 Sept 2015] (cross-list from hep-ph)
Structure of near-threshold quasi-bound states
Yuki Kamiya🇯🇵 · Tetsuo Hyodo🇯🇵
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.
- Comments:
- 5 pages, no figure, v3: published version
- Subjects:
- High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Theory (nucl-th)
- arXiv:
- 1509.00146 [pdf]