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arXiv · hep-ph/9601252

The rare decay $η\toππγγ$ in chiral perturbation theory

G. Kn"ochlein·S. Scherer·D. Drechsel
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Abstract

We investigate the rare radiative eta decay modes $η\toπ^+π^-γγ$ and $η\toπ^0π^0γγ$ within the framework of chiral perturbation theory at $O(p^4)$. We present photon spectra and partial decay rates for both processes as well as a Dalitz contour plot for the charged decay.

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G. Kn"ochlein, S. Scherer, D. Drechsel. 1996-01-12. The rare decay $η\toππγγ$ in chiral perturbation theory. https://doi.org/10.1103/physrevd.53.3634

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