Higher-order QCD corrections to top-quark pair production in association with a jet

TL;DR

This paper presents the first next-to-next-to-leading order QCD predictions for top-quark pair production with a jet, significantly improving the precision of differential cross section calculations crucial for Standard Model tests.

Contribution

It introduces the first NNLO QCD calculations for top-quark pair plus jet production, including two-loop amplitudes in the leading-color approximation, reducing theoretical uncertainties.

Findings

Perturbative predictions show improved convergence.

Uncertainties from missing higher orders are significantly reduced.

Provides estimates for the impact of missing contributions.

Abstract

The production of a top-quark pair, the heaviest known elementary particle, in association with a light jet is a key process for studying the properties of the Standard Model of Particle Physics. Due to its significance as a signal process with considerable sensitivity to the top-quark mass and as a background process for new physics searches, it is crucial to predict differential cross sections with high precision. In this article, we present, for the first time, predictions for various kinematical observables at next-to-next-to-leading order in Quantum Chromodynamics. The perturbative behavior is analyzed, and uncertainties arising from missing higher-order contributions are substantially reduced. The necessary two-loop amplitudes have been evaluated in the leading-color approximation, and we provide estimates for the impact of the missing contributions.