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arXiv · 2410.13304

Precision tests of third-generation four-quark operators: one- and two-loop matching

Ulrich Haisch·Luc Schnell
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Abstract

We calculate the one- and two-loop matching corrections in the Standard Model effective field theory (SMEFT) that impact electroweak precision measurements and flavour physics observables, focusing on the contributions of third-generation four-quark operators. Our results provide a crucial ingredient for a model-independent analysis of constraints on beyond the Standard Model physics that primarily affects the sector of third-generation four-quark operators. Concise analytic expressions are provided for all considered precision observables, which should facilitate their inclusion into global SMEFT analyses.

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Ulrich Haisch, Luc Schnell. 2024-10-17. Precision tests of third-generation four-quark operators: one- and two-loop matching. https://arxiv.org/abs/2410.13304

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