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arXiv · hep-ph/0405250

Vector Meson Contributions in epsilon'/epsilon

Anirban Kundu·Emmanuel A. Paschos·Yu-Feng Zhou
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Abstract

The CP violating parameter epsilon'/epsilon is computed using the low-energy dynamics of a chiral theory supplemented by vector resonances. The divergent contributions coming from strong pi-pi scattering are tamed by vector-meson exchange terms. This amounts to softening the fast growing high-energy behaviour of pi-pi scattering. The final result for epsilon'/epsilon shows a smooth dependence on the cut-off where low energy dynamics is matched with that of QCD.

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Anirban Kundu, Emmanuel A. Paschos, Yu-Feng Zhou. 2004-08-01. Vector Meson Contributions in epsilon'/epsilon. https://doi.org/10.1016/j.physletb.2004.06.096

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