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arXiv · 1606.06054

$B^0-\bar{B}^0$ Mixing at Next-to-Leading Order

Andrey G. Grozin·Rebecca Klein·Thomas Mannel·Alexei A. Pivovarov
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Abstract

We compute the perturbative corrections to the HQET sum rules for the matrix element of the \Delta B=2 operator that determines the mass shift of $B^0$, $\bar{B}^0$ states. Technically, we obtain analytically the non-factorizable contributions at order $\alpha_s$ to the bag parameter that first appear at the three-loop level. Together with the known non-perturbative corrections due to vacuum condensates and $1/m_b$ corrections, the full next-to-leading order result is now available. We present a numerical value for the renormalization group invariant bag parameter that is phenomenologically relevant and discuss comparison with recent lattice determinations.

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Andrey G. Grozin, Rebecca Klein, Thomas Mannel, Alexei A. Pivovarov. 2016-06-20. $B^0-\bar{B}^0$ Mixing at Next-to-Leading Order. https://doi.org/10.1103/physrevd.94.034024

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