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arXiv · hep-ph/9511397

Elastic $ππ$ scattering to two loops

J. Bijnens·G. Colangelo·G. Ecker·J. Gasser·M. E. Sainio
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Abstract

We evaluate analytically the elastic $ππ$ scattering amplitude to two loops in chiral perturbation theory and give numerical values for the two $S$--wave scattering lengths and for the phase shift difference $δ_0^0-δ_1^1$.

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J. Bijnens, G. Colangelo, G. Ecker, J. Gasser, M. E. Sainio. 1995-11-23. Elastic $ππ$ scattering to two loops. https://doi.org/10.1016/0370-2693(96)00165-7

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