EFT results in the top quark sector in CMS

TL;DR

This paper summarizes CMS's recent indirect searches in the top-quark sector using SMEFT, including CP violation studies, flavor structure measurements, and combined analyses, with outlook on future sensitivity improvements.

Contribution

It presents new CMS results on top-quark sector SMEFT interpretations, employing advanced machine learning and combined measurements for the first time.

Findings

Evidence of CP violation in top-quark processes

Disentangled flavor structure of SMEFT couplings

Enhanced sensitivity expected at high-luminosity LHC

Abstract

The CMS programme of indirect searches in the top-quark sector interprets precision measurements in the Standard Model Effective Field Theory (SMEFT) framework. These proceedings summarize recent CMS results highlighted in the TOP2025 talk: a search for CP violation in ttZ and tZq production using CP-odd observables constructed with physics-informed machine learning, a measurement that disentangles the flavour structure of electroweak SMEFT couplings in multilepton final states, and a Run 2 combination of complementary top+X measurements. We close with a brief outlook on the expected sensitivity gains at the high-luminosity LHC.