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arXiv · hep-lat/9402011

Scattering phases on finite lattices in the broken phase of the four-dimensional O(4)-ϕ^4 theory

M. Goeckeler·H. A. Kastrup·J. Westphalen·F. Zimmermann
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Abstract

According to a proposal of Luescher 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 four-dimensional O(4) non-linear sigma-model in a Monte Carlo study on finite lattices. This non-perturbative approach also permits the study of unstable particles, the sigma-particle in our case. We observe the sigma-resonance and extract its mass and width. In all scattering channels investigated the results are completely consistent with perturbative calculations.

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M. Goeckeler, H. A. Kastrup, J. Westphalen, F. Zimmermann. 1994-02-15. Scattering phases on finite lattices in the broken phase of the four-dimensional O(4)-ϕ^4 theory. https://doi.org/10.1016/0550-3213(94)90186-4

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