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arXiv · 0710.4456

Cusps in K_L --> 3 pi decays

M. Bissegger·A. Fuhrer·J. Gasser·B. Kubis·A. Rusetsky
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Abstract

The pion mass difference generates a pronounced cusp in K --> 3 pi decays, the strength of which is related to the pi pi S-wave scattering lengths. We apply an effective field theory framework developed earlier to evaluate the amplitudes for K_L --> 3 pi decays in a systematic manner, where the strictures imposed by analyticity and unitarity are respected automatically. The amplitudes for the decay eta --> 3 pi are also given.

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M. Bissegger, A. Fuhrer, J. Gasser, B. Kubis, A. Rusetsky. 2007-10-24. Cusps in K_L --> 3 pi decays. https://doi.org/10.1016/j.physletb.2007.11.008

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