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arXiv · hep-ph/0603013

$B \to ππ$ decays: branching ratios and CP asymmetries

A. B. Kaidalov·M. I. Vysotsky
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Abstract

Theoretically motivated smallness of the penguin amplitude in $B \to ππ$ decays allowes to calculate the value of the unitarity triangle angle $α(ϕ_2)$ with good accuracy. The relatively large branching ratio of the decay into $π^0 π^0$ is explained by the large value of FSI phase difference between $ΔI = 1/2$ and $ΔI = 3/2$ tree amplitudes.

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A. B. Kaidalov, M. I. Vysotsky. 2006-09-13. $B \to ππ$ decays: branching ratios and CP asymmetries. https://doi.org/10.1134/s1063778807040138

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