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Analyzing B_s - bar B_s mixing: Non-perturbative contributions to bag parameters from sum rules

T. Mannel·B. D. Pecjak·A. A. Pivovarov
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Abstract

We use QCD sum rules to compute matrix elements of the Delta B=2 operators appearing in the heavy-quark expansion of the width difference of the B_s mass eigenstates. Our analysis includes the leading-order operators Q and Q_S, as well as the subleading operators R_2 and R_3, which appear at next-to-leading order in the 1/m_b expansion. We conclude that the violation of the factorization approximation for these matrix elements due to non-perturbative vacuum condensates is as low as 1-2%.

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T. Mannel, B. D. Pecjak, A. A. Pivovarov. 2007-03-22. Analyzing B_s - bar B_s mixing: Non-perturbative contributions to bag parameters from sum rules. https://arxiv.org/abs/hep-ph/0703244

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