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Tracking down penguins at the poles

Jean-Marc Gerard·Christopher Smith·Stephanie Trine
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Abstract

QCD penguins are responsible for about 2/3 of the Delta I=1/2 rule in K to pi pi decays, as inferred from a combined analysis of K to pi pi and KL to gamma gamma. Further tests based on the decays KS to pi0 gamma gamma and K+ to pi+ gamma gamma are proposed. New insights into the treatment of pi0, eta, eta' pole amplitudes are also reported.

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Jean-Marc Gerard, Christopher Smith, Stephanie Trine. 2006-05-14. Tracking down penguins at the poles. https://arxiv.org/abs/hep-ph/0605165

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