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

Author:

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

Keyword:

High Energy Physics - Phenomenology, High Energy Physics - Phenomenology (hep-ph)

journal:

P3H-23-080, KA-TP-22-2023, TTP23-054

date:

2023-10-26 16:00:00

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.

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