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arXiv · 2401.16904

A Simple Dirac Prescription for Two-Loop Anomalous Dimension Matrices

Jason Aebischer·Marko Pesut·Zachary Polonsky
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Abstract

A novel method to treat effects from evanescent operators in next-to-leading order (NLO) computations is introduced. The approach allows, besides further simplifications, to discard evanescent-to-physical mixing contributions in NLO calculations. The method is independent of the treatments of $\gamma_5$ and can therefore be combined with different renormalization schemes. We illustrate the utility of this result by reproducing literature results of two-loop anomalous dimension matrices for both $|\Delta F| = 1$ and $|\Delta F| = 2$ transitions.

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Jason Aebischer, Marko Pesut, Zachary Polonsky. 2024-01-30. A Simple Dirac Prescription for Two-Loop Anomalous Dimension Matrices. https://arxiv.org/abs/2401.16904

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