Energy dependence of the $\bar{K}N$ interaction and the two-pole structure of the $\Lambda(1405)$ -- are they real?

János Révai

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arXiv · 1811.09039

Energy dependence of the $\bar{K}N$ interaction and the two-pole structure of the $\Lambda(1405)$ -- are they real?

János Révai

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Abstract

It is shown, that the energy dependence of the chiral based $\bar{K}N$ potentials, responsible for the ocurence of two poles in the $I=0$ sector is the consequence of applying the on-shell factorization approximation [1]. When the dynamical equation is solved without this approximation, the $T$-matrix has only one pole in the region of the $\Lambda(1405)$ resonance.

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János Révai. 2018-11-22. Energy dependence of the $\bar{K}N$ interaction and the two-pole structure of the $\Lambda(1405)$ -- are they real?. https://arxiv.org/abs/1811.09039

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