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arXiv · 1602.08852

Antikaon-nucleon interaction and Lambda(1405) in chiral SU(3) dynamics

Abstract

The properties of the Lambda(1405) resonance are key ingredients for determining the antikaon-nucleon interaction in strangeness nuclear physics, and the novel internal structure of the Lambda(1405) is of great interest in hadron physics, as a prototype case of a baryon that does not fit into the simple three-quark picture. We show that a quantitative description of the antikaon-nucleon interaction with the Lambda(1405) is achieved in the framework of chiral SU(3) dynamics, with the help of recent experimental progress. Further constraints on the Kbar N subthreshold interaction are provided by analyzing pi Sigma spectra in various processes, such as the K-d -> pi Sigma n reaction and the Lambda_c -> pi pi Sigma decay. The structure of the Lambda(1405) is found to be dominated by an antikaon-nucleon molecular configuration, based on its wavefunction derived from a realistic Kbar N potential and the compositeness criteria from a model-independent weak-binding relation.

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Yuki Kamiya, Kenta Miyahara, Shota Ohnishi, Yoichi Ikeda, Tetsuo Hyodo, Eulogio Oset, Wolfram Weise. 2016-02-29. Antikaon-nucleon interaction and Lambda(1405) in chiral SU(3) dynamics. https://doi.org/10.1016/j.nuclphysa.2016.04.013

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