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arXiv · hep-ph/9511335

Simple Description of Pion-Pion Scattering to 1 GeV

Masayasu Harada·Francesco Sannino·Joseph Schechter
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Abstract

Motivated by the 1/Nc expansion, we present a simple model of pion-pion scattering as a sum of a `current-algebra' contact term and resonant pole exchanges. The model preserves crossing symmetry as well as unitarity up to 1.2 GeV. Key features include chiral dynamics, vector meson dominance, a broad low energy scalar (sigma) meson and a `Ramsauer-Townsend' mechanism for the understanding of the 980 MeV region. We discuss in detail the `regularization' (corresponding to rescattering effects) necessary to make all these nice features work.

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Masayasu Harada, Francesco Sannino, Joseph Schechter. 1995-11-16. Simple Description of Pion-Pion Scattering to 1 GeV. https://doi.org/10.1103/physrevd.54.1991

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