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pi-pi scattering amplitudes constrained by Roy's equations

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

The scalar-isoscalar, scalar-isotensor and vector-isovector pi-pi amplitudes have been fitted simultaneously to experimental data and to to Roy's equations. Resulting pi-pi phase shifts up to 1600 MeV and near threshold observables have been analyzed. Only the amplitudes fitted to the "down-flat" set of phase shifts in scalar-isoscalar wave fulfill crossing symmetry conditions and can be regarded as physical.

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R. Kaminski, L. Lesniak, B. Loiseau. 2005-10-17. pi-pi scattering amplitudes constrained by Roy's equations. https://arxiv.org/abs/hep-ph/0510218

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