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arXiv · hep-ph/9512296

$γγ\to πππ$ to One Loop in Chiral Perturbation Theory

P. Talavera·Ll. Ametller·J. Bijnens·A. Bramon·F. Cornet
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Abstract

The $γγ\to π^0 π^0 π^0$ and $γγ\to π^+ π^- π^0$ amplitudes are discussed in the general context of Chiral Perturbation Theory (ChPT) to $O(p^6)$. Chiral loops are found to play a major role. This makes these processes a good test of ChPT, mainly in its anomalous sector. We correct earlier numerical results at tree level and determine the one-loop results as well.

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P. Talavera, Ll. Ametller, J. Bijnens, A. Bramon, F. Cornet. 1996-03-01. $γγ\to πππ$ to One Loop in Chiral Perturbation Theory. https://doi.org/10.1016/0370-2693(96)00299-7

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