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arXiv · 2007.03392

Density of States of a Coupled-Channel System

Pok Man Lo
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Abstract

We demonstrate how an effective density of states can be derived from the S-matrix describing a coupled-channel system. Besides the locations of poles, the phase of the determinant of the S-matrix encodes essential details in characterizing the dynamics of resonant and non-resonant interactions. The density of states is computed for the two channel scattering problem ($\pi\pi, K \bar{K}$, S-wave), and the influences from the various dynamical structures: poles, roots, branch cuts, and Riemann sheets, are examined.

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Pok Man Lo. 2020-07-07. Density of States of a Coupled-Channel System. https://doi.org/10.1103/physrevd.102.034038

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