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arXiv · hep-ph/9603345

Radiative Four--Meson Amplitudes in Chiral Perturbation Theory

G. D'Ambrosio·G. Ecker·G. Isidori·H. Neufeld
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Abstract

We present a general discussion of radiative four--meson processes to $O(p^4)$ in chiral perturbation theory. We propose a definition of ``generalized bremsstrahlung'' that takes full advantage of experimental information on the corresponding non--radiative process. We also derive general formulae for one--loop amplitudes which can be applied, for instance, to $η\ra 3πγ$, $ππ\ra ππγ$ and $K \ra 3πγ$.

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G. D'Ambrosio, G. Ecker, G. Isidori, H. Neufeld. 1996-03-19. Radiative Four--Meson Amplitudes in Chiral Perturbation Theory. https://doi.org/10.1016/0370-2693(96)00520-5

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