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arXiv · 0904.1320

The cusp effect in eta' --> eta pi pi decays

Bastian Kubis·Sebastian P. Schneider
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Abstract

Strong final-state interactions create a pronounced cusp in eta' --> eta pi0 pi0 decays. We adapt and generalize the non-relativistic effective field theory framework developed for the extraction of pi pi scattering lengths from K --> 3 pi decays to this case. The cusp effect is predicted to have an effect of more than 8% on the decay spectrum below the pi+ pi- threshold.

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Bastian Kubis, Sebastian P. Schneider. 2009-06-11. The cusp effect in eta' --> eta pi pi decays. https://doi.org/10.1140/epjc%2Fs10052-009-1054-7

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