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arXiv · hep-ph/9602429

Charged Pion-Pair Production and Pion Polarizabilities to two Loops

Urs Buergi
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Abstract

We evaluate the amplitude for gamma gamma --> pi^+ pi^- to two loops in the framework of chiral perturbation theory.The three new coupling constants that enter the result at this order in the low-energy expansion are estimated via resonance saturation. We discuss in addition the crossed channel processes gamma pi^+ --> gamma pi^+ - in particular the charged pion polarizabilities - to the same accuracy. The predictions are compared with available experimental information.

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Urs Buergi. 1996-02-29. Charged Pion-Pair Production and Pion Polarizabilities to two Loops. https://doi.org/10.1016/0550-3213(96)00454-3

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