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Lifetime Differences and CP Violation Parameters of Neutral B Mesons at the Next-to-Leading Order in QCD

M. Ciuchini·E. Franco·V. Lubicz·F. Mescia·C. Tarantino
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Abstract

We compute the next-to-leading order QCD corrections to the off-diagonal elements of the decay-width matrix Gamma entering the neutral B-meson oscillations. From this calculation the width differences DeltaGamma and the CP violation parameters (q/p) of Bd and Bs mesons are estimated, including the complete O}(alpha_s) QCD corrections and the 1/mb contributions. For the width difference DeltaGamma_s we agree with previous results. By using the lattice determinations of the relevant hadronic matrix elements we obtain the theoretical predictions DeltaGamma_d/Gamma_d=(2.42+-0.59) x 10^(-3) and DeltaGamma_s/Gamma_s=(7.4+-2.4) x 10^(-2). For the CP violation parameters, we find |(q/p)_d|-1=(2.96+-0.67) x 10^(-4) and |(q/p)_s|-1=(-1.28+-0.27) x 10^(-5). These predictions are compatible with the experimental measurements which, however, suffer at present from large uncertainties.

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M. Ciuchini, E. Franco, V. Lubicz, F. Mescia, C. Tarantino. 2003-09-10. Lifetime Differences and CP Violation Parameters of Neutral B Mesons at the Next-to-Leading Order in QCD. https://doi.org/10.1088/1126-6708%2F2003%2F08%2F031

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