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arXiv · hep-ph/0307344

CP asymmetry in flavour-specific B decays beyond leading logarithms

M. Beneke·G. Buchalla·A. Lenz·U. Nierste
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Abstract

We compute next-to-leading order QCD corrections to the CP asymmetry a_{fs} = Im(Gamma_{12}/M_{12}) in flavour-specific B_{d,s} decays such as B_d->X l nu or B_s->D^-_s pi^+. The corrections reduce the uncertainties associated with the choice of the renormalization scheme for the quark masses significantly. In the Standard Model we predict a^d_{fs} = -(5.0 +- 1.1)*10^{-4}. As a by-product we also obtain the width difference in the B_d system at next-to-leading order in QCD.

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M. Beneke, G. Buchalla, A. Lenz, U. Nierste. 2003-08-21. CP asymmetry in flavour-specific B decays beyond leading logarithms. https://doi.org/10.1016/j.physletb.2003.09.089

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