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arXiv · hep-ph/9707394

Two loops calculation in chiral perturbation theory and the unitarization program of current algebra

J. Sá Borges·J. Soares Barbosa·M. D. Tonasse
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Abstract

In this paper we compare two loop Chiral Perturbation Theory (ChPT) calculation of pion-pion scattering with the unitarity second order correction to the current algebra soft-pion theorem. It is shown that both methods lead to the same analytic structure for the scattering amplitude.

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J. Sá Borges, J. Soares Barbosa, M. D. Tonasse. 1997-07-18. Two loops calculation in chiral perturbation theory and the unitarization program of current algebra. https://doi.org/10.1103/physrevd.57.4108

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