The absence of direct evidence for new particles at the LHC has shifted the emphasis of the experimental program toward precision measurements as indirect probes of new interactions. The top-quark sector provides a particularly sensitive laboratory within the Standard Model Effective Field Theory (SMEFT) framework. This article reviews three recent CMS results that constrain electroweak interactions of the top quark: a search for CP violation in associated \(t\bar{t}Z\) and \(tZq\) production using CP-odd observables, a multilepton measurement probing the flavor structure of electroweak SMEFT couplings, and a Run 2 statistical combination of complementary top+X analyses. Their interpretation is discussed with explicit attention to EFT truncation, interference versus quadratic contributions, and the role of dimension-eight effects. Prospects for global SMEFT interpretations at the High-Luminosity LHC are examined.
- Open Access
- Article
Indirect Probes of Electroweak Interactions in the Top-Quark Sector: Recent SMEFT Results from CMS
- Andrea Piccinelli
Author Information
Received: 02 Mar 2026 | Revised: 20 Mar 2026 | Accepted: 23 Mar 2026 | Published: 27 Mar 2026
Abstract
Keywords
top quark | SMEFT | electroweak interactions | CP violation | multilepton final states | High-Luminosity LHC
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