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arXiv · hep-lat/9211029

Unstable particles in finite volume: The broken phase of the $4$-d $O(4)$ non-linear $σ$-model

Frank Zimmermann·Jörg Westphalen·Meinulf Göckeler·Hans A. Kastrup
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Abstract

According to a proposal of Lüscher it is possible to determine elastic scattering phases in infinite volume from the energy spectrum of two-particle states in a periodic box. We demonstrate the applicability of this method in the broken phase of the 4-dimensional $O(4)$ non-linear $σ$-model in a Monte-Carlo study on finite lattices. This non-perturbative approach also permits the study of unstable particles, the $\sg$-particle in our case. We observe the $\sg$-resonance and extract its mass and its width.

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Frank Zimmermann, Jörg Westphalen, Meinulf Göckeler, Hans A. Kastrup. 1992-11-11. Unstable particles in finite volume: The broken phase of the $4$-d $O(4)$ non-linear $σ$-model. https://doi.org/10.1016/0920-5632(93)90347-9

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