2–6 Jun 2025
CERN
Europe/Zurich timezone

Electroweak corrections in the SMEFT: four-fermion operators at high energies

4 Jun 2025, 12:10
15m
503/1-001 - Council Chamber (CERN)

503/1-001 - Council Chamber

CERN

162
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Speaker

Ken Mimasu

Description

In the Standard Model (SM), electroweak (EW) corrections become significant at high energies, particularly at the tera-electronvolt scale and beyond, due to the presence of Sudakov logarithms. At these energy scales, the Standard Model Effective Field Theory (SMEFT) framework provides an enhanced sensitivity to potential new physics effects. This motivates the inclusion of EW corrections not only for SM predictions but also for analyses within SMEFT.
In this work, we compute EW corrections in the high-energy limit for a selected set of dimension-six operators, specifically the class of four-fermion contact interactions, in key hard-scattering processes relevant to both current and future colliders: top-quark pair production at the Large Hadron Collider (LHC) and in a muon collider scenario, as well as the Drell-Yan process at the LHC. We first discuss the technical details and challenges associated with evaluating EW Sudakov logarithms in SMEFT, contrasting them with the SM case. We then present phenomenological results for the aforementioned processes, highlighting the non-trivial effects introduced by EW corrections arising from the insertion of dimension-six, four-fermion operators. Importantly, the resulting k-factors exhibit significant deviations from their SM counterparts, with dependencies not only on the process but also on the specific operators considered.
Finally, we explore the potential to lift flat directions in the SMEFT parameter space by incorporating higher-order corrections, using Fisher information techniques.

Authors

Davide Pagani (INFN, Bologna (IT)) Eleni Vryonidou (The University of Manchester (GB)) Hesham El Faham (The University of Manchester) Ken Mimasu Marco Zaro (Università degli Studi e INFN Milano (IT))

Presentation materials