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Master Formulae for Delta F=2 NLO-QCD Factors in the Standard Model and Beyond

Andrzej J. Buras·Sebastian Jager·Joerg Urban
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Abstract

We present analytic formulae for the QCD renormalization group factors relating the Wilson coefficients C_i(mu_t) and C_i(mu), with mu_t = O(m_t) and mu < mu_t, of the Delta F=2 dimension six four-quark operators Q_i in the Standard Model and in all of its extensions. Analogous analytic formulae for the QCD factors relating the matrix elements and with mu_K < 2GeV are also presented. The formulae are given in the NDR scheme. The strongest renormalization-group effects are found for the operators with the Dirac structures (1 - gamma_5)*(1 + gamma_5) and (1 - gamma_5)*(1 - gamma_5). We calculate the matrix elements <\bar K^0|Q_i|K^0> in the NDR scheme using the lattice results in the LRI scheme. We give expressions for the mass differences Delta M_K and Delta M_B and the CP-violating parameter epsilon_K in terms of the non-perturbative parameters B_i and the Wilson coefficients C_i(mu_t). The latter summarize the dependence on new physics contributions.

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Andrzej J. Buras, Sebastian Jager, Joerg Urban. 2001-02-26. Master Formulae for Delta F=2 NLO-QCD Factors in the Standard Model and Beyond. https://doi.org/10.1016/s0550-3213(01)00207-3

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