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QCD factorisation and flavour symmetries illustrated in B_d,s -> KK decays

S. Descotes-Genon
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Abstract

We present a new analysis of B_d,s -> KK modes within the SM, relating them in a controlled way through SU(3)-flavour symmetry and QCD-improved factorisation. We propose a set of sum rules for B_d,s -> K^0 \bar K^0 observables. We determine B_s -> KK branching ratios and CP-asymmetries as functions of A_dir(B_d -> K^0 \bar K^0), with a good agreement with current experimental measurements of CDF. Finally, we predict the amount of U-spin breaking between B_d -> pi+ pi- and B_s -> K+K-.

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S. Descotes-Genon. 2007-02-01. QCD factorisation and flavour symmetries illustrated in B_d,s -> KK decays. https://arxiv.org/abs/hep-ph/0702013

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