Differential $t\bar{t}$ cross-section measurements using boosted top quarks with 139 fb$^{-1}$ of ATLAS data

TL;DR

This paper presents measurements of the differential cross-section of top-antitop quark pairs at high transverse momentum using the full ATLAS Run 2 dataset, comparing results with Standard Model predictions and constraining new physics.

Contribution

It provides the first detailed differential cross-section measurements for boosted top quarks in both lepton+jets and all-hadronic channels at 13 TeV with 139 fb$^{-1}$ of data, and sets limits on effective field theory parameters.

Findings

Measured spectra agree with Standard Model predictions.

Set limits on Wilson coefficients of effective field theory extensions.

Enhanced understanding of top quark production at high transverse momentum.

Abstract

Preliminary results of two differential cross-section measurements in the ATLAS experiment at CERN are presented. Measurements are focused on the top-antitop quark pair production in the~lepton+jets and the~all-hadronic channels in the kinematic region with high transverse momentum top quarks. Both measurements use the full Run 2 data of 13 TeV proton-proton collisions from the Large Hadron Collider collected by the ATLAS detector in 2015-2018, corresponding to an integrated luminosity of 139 fb$^{-1}$. The measured spectra are compared with the Standard Model predictions. They are also used to set limits on the Wilson coefficients of an effective field theory extension of the Standard Model.