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arXiv · hep-ph/0210334

Elimination of ambiguities in pion-pion phase shifts using crossing symmetry

R. Kaminski·L. Lesniak·B. Loiseau
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Abstract

Roy's equations, which incorporate crossing symmetry of the pion-pion scattering amplitudes, are used to resolve the present ambiguity between two solutions for the scalar-isoscalar phase shifts below 1 GeV. It is shown that the "down-flat" solution satisfies well Roy's equations and consequently crossing symmetry while the other solution called "up-flat" does not and thus should be eliminated.

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R. Kaminski, L. Lesniak, B. Loiseau. 2002-10-24. Elimination of ambiguities in pion-pion phase shifts using crossing symmetry. https://doi.org/10.1016/s0370-2693(02)03021-6

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