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Standard Model Matrix Elements for Neutral B-Meson Mixing and Associated Decay Constants

UKQCD Collaboration·Laurent Lellouch·C. -J. David Lin
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Abstract

We present results of quenched lattice calculations of the matrix elements relevant for B_d-\bar B_d and B_s-\bar B_s mixing in the Standard Model. Results for the corresponding SU(3)-breaking ratios, which can be used to constrain or determine |V_{td}|, are also given. The calculations are performed at two values of the lattice spacing, corresponding to β= 6.0 and β= 6.2, with quarks described by a mean-field-improved Sheikholeslami-Wohlert action. As a by-product, we obtain the leptonic decay constants of B and D mesons. We also present matrix elements relevant for D^0-\bar D^0 mixing. Our results are summarized in the Introduction.

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UKQCD Collaboration, Laurent Lellouch, C. -J. David Lin. 2002-02-28. Standard Model Matrix Elements for Neutral B-Meson Mixing and Associated Decay Constants. https://doi.org/10.1103/physrevd.64.094501

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