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arXiv · hep-ph/0004004

Fat penguins and imaginary penguins in perturbative QCD

Yong-Yeon Keum·Hsiang-nan Li·A. I. Sanda
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Abstract

We evaluate $B\to Kπ$ decay amplitudes in perturbative QCD picture. It is found that penguin contributions are dynamically enhanced by nearly 50% compared to those assumed in the factorization approximation. It is also shown that annihilation diagrams are not negligible, and give large strong phases. Our results for branching ratios of $B\to Kπ$ decays for a representative parameter set are consistent with data. We evaluate $B\to Kπ$ decay amplitudes in perturbative QCD picture. It is found that penguin contributions are dynamically enhanced by nearly 50% compared to those assumed in the factorization approximation. It is also shown that annihilation diagrams are not negligible, and give large strong phases. Our results for branching ratios of $B\to Kπ$ decays for a representative parameter set are consistent with data.

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Yong-Yeon Keum, Hsiang-nan Li, A. I. Sanda. 2001-01-12. Fat penguins and imaginary penguins in perturbative QCD. https://doi.org/10.1016/s0370-2693(01)00247-7

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