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Two-Loop QCD Anomalous Dimensions of Flavour-Changing Four-Quark Operators Within and Beyond the Standard Model

Andrzej J. Buras·Mikolaj Misiak·Joerg Urban
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Abstract

We calculate the two-loop QCD anomalous dimension matrix (ADM) gamma^(1)_NDR in the NDR-MSbar scheme for all the flavour-changing four-quark dimension-six operators that are relevant in both the Standard Model and its extensions. Both current-current and penguin diagrams are included. Some of our NDR-MSbar results for Delta F=1 operators overlap with the previous calculations, but several others have never been published before. In the case of Delta F=2 operators, our results are compatible with the ones obtained by Ciuchini et al. in the Regularization-Independent renormalization scheme, but differ from their NDR-MSbar results. In order to explain the difference, we calculate the ADM of Delta F=2 operators again, extracting it from the ADM of Delta F=1 operators.

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Andrzej J. Buras, Mikolaj Misiak, Joerg Urban. 2024-02-14. Two-Loop QCD Anomalous Dimensions of Flavour-Changing Four-Quark Operators Within and Beyond the Standard Model. https://doi.org/10.1016/s0550-3213(00)00437-5

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