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Two-Loop Chiral Perturbation Theory and the Pion-Pion Phase Shifts

J. Sa Borges·J. Soares Barbosa·M. D. Tonasse·J. Haidenbauer
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Abstract

We want to test the predictive power of Chiral Perturbation Theory (ChPT). In this work, we use the ChPT pion-pion scattering amplitude, including two loop contributions, and we obtain S- and P-wave low-energy phase shifts. We show that, by varying just one free parameter, the resulting S- and P-wave phase shifts are in reasonable agreement with the experimental data.

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J. Sa Borges, J. Soares Barbosa, M. D. Tonasse, J. Haidenbauer. 1998-06-26. Two-Loop Chiral Perturbation Theory and the Pion-Pion Phase Shifts. https://arxiv.org/abs/hep-ph/9806500

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