On $\gamma_5$ schemes and the interplay of SMEFT operators in the Higgs-gluon coupling

Stefano Di Noi; Ramona Gröber; Gudrun Heinrich; Jannis Lang; Marco Vitti

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arXiv · 2310.18221

On $\gamma_5$ schemes and the interplay of SMEFT operators in the Higgs-gluon coupling

Stefano Di Noi·Ramona Gröber·Gudrun Heinrich·Jannis Lang·Marco Vitti

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Abstract

We calculate the four-top quark operator contributions to Higgs production via gluon fusion in the Standard Model Effective Field Theory. The four-top operators enter for the first time via two-loop diagrams. Due to their chiral structure they contain $\gamma_5$, so special care needs to be taken when using dimensional regularisation for the loop integrals. We use two different schemes for the continuation of $\gamma_5$ to $D$ space-time dimensions in our calculations and present a mapping for the parameters in the two schemes. This generically leads to an interplay of different operators, such as four-top operators, chromomagnetic operators or Yukawa-type operators at the loop level. We validate our results by examples of matching onto UV models.

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Stefano Di Noi, Ramona Gröber, Gudrun Heinrich, Jannis Lang, Marco Vitti. 2023-10-27. On $\gamma_5$ schemes and the interplay of SMEFT operators in the Higgs-gluon coupling. https://arxiv.org/abs/2310.18221

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