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arXiv · 0810.1906

Dispersive representation of K -> 3 pi amplitudes and cusps

Karol Kampf·Marc Knecht·Jiri Novotny·Martin Zdrahal
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Abstract

The NA48/2 collaboration has shown clear experimental evidence for a cusp in the data for K -> pi pi^0 pi^0. This effect can be used to extract information on the pi-pi scattering lengths. We address this issue using a two-loop dispersive construction of pi pi -> pi pi and K -> pi pi pi amplitudes in the presence of isospin breaking.

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Karol Kampf, Marc Knecht, Jiri Novotny, Martin Zdrahal. 2008-10-10. Dispersive representation of K -> 3 pi amplitudes and cusps. https://doi.org/10.1016/j.nuclphysbps.2008.12.075

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