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Chiral-loop and vector-meson contributions to eta -> pi pi gamma gamma decays

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

The process eta -> pi0 pi0 gamma gamma is discussed in Chiral Perturbation Theory (ChPT) extending two recent analyses. Special attention is devoted to one-loop corrections, eta-eta' mixing effects and vector-meson dominance of ChPT counter-terms. The less interesting eta -> pi^+ pi^- gamma gamma transition is briefly discussed too.

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Ll. Ametller, J. Bijnens, A. Bramon, P. Talavera. 1997-02-11. Chiral-loop and vector-meson contributions to eta -> pi pi gamma gamma decays. https://doi.org/10.1016/s0370-2693(97)00378-x

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