O new physics, where art thou? A global search in the top sector

TL;DR

This paper conducts a comprehensive global analysis of LHC Run II top measurements using dimension-6 operators, highlighting the importance of four-quark operators and the impact of quadratic terms on Wilson coefficient limits.

Contribution

It provides the first detailed NLO QCD predictions for top observables with a focus on four-quark operators and discusses the role of quadratic terms in setting stable limits.

Findings

Quadratic terms stabilize limits on Wilson coefficients.

Theoretical uncertainties significantly affect the analysis.

Four-quark operators are crucial in top sector studies.

Abstract

We provide a comprehensive global analysis of Run II top measurements at the LHC in terms of dimension-6 operators. A distinctive feature of the top sector as compared to the Higgs-electroweak sector is the large number of four-quark operators. We discuss in detail how they can be tested and how quadratic terms lead to a stable limit on each individual Wilson coefficient. Predictions for all observables are computed at NLO in QCD. Our SFitter analysis framework features a detailed error treatment and shows that theoretical uncertainties are a limiting factor.