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arXiv · 2310.14937

On the generalized Friedrichs-Lee model with multiple discrete and continuous states

Zhiguang Xiao·Zhi-Yong Zhou
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Abstract

In this study, we present several improvements of the non-relativistic Friedrichs-Lee model with multiple discrete and continuous states and still retain its solvability. Our findings establish a solid theoretical basis for the exploration of resonance phenomena in scenarios involving multiple interfering states across various channels. The scattering amplitudes associated with the continuum states naturally adhere to coupled-channel unitarity, rendering this framework particularly valuable for investigating hadronic resonant states appearing in multiple coupled channels. Moreover, this generalized framework exhibits a wide-range applicability, enabling investigations into resonance phenomena across diverse physical domains, including hadron physics, nuclear physics, optics, and cold atom physics, among others.

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Zhiguang Xiao, Zhi-Yong Zhou. 2023-10-23. On the generalized Friedrichs-Lee model with multiple discrete and continuous states. https://arxiv.org/abs/2310.14937

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