Inclusive and differential cross-sections for dilepton t¯t production measured in p s = 13 TeV pp collisions with the ATLAS detector

Differential and double-differential distributions of kinematic variables of leptons from decays of top-quark pairs (tt¯ ) are measured using the full LHC Run 2 data sample collected with the ATLAS detector. The data were collected at a pp collision energy of s√ = 13 TeV and correspond to an integrated luminosity of 140 fb−1. The measurements use events containing an oppositely charged eμ pair and b-tagged jets. The results are compared with predictions from several Monte Carlo generators. While no prediction is found to be consistent with all distributions, a better agreement with measurements of the lepton pT distributions is obtained by reweighting the tt¯ sample so as to reproduce the top-quark pT distribution from an NNLO calculation. The inclusive top-quark pair production cross-section is measured as well, both in a fiducial region and in the full phase-space. The total inclusive cross-section is found to be σtt¯=829±1 (stat)±13 (syst)±8 (lumi)±2 (beam) pb, where the uncertainties are due to statistics, systematic effects, the integrated luminosity and the beam energy. This is in excellent agreement with the theoretical expectation. ; CEA-DRF ; Cantons of Bern and Geneva ; DNSRC ; EU-ESF ; GenT Programmes Generalitat Valenciana, Spain ; La Caixa Banking Foundation ; MIZŠ ; MNE ; Norwegian Financial Mechanism ; PROMETEO ; RGC ; UNCE ; Wallenberg Foundation ; National Science Foundation ; U.S. Department of Energy ; Alexander von Humboldt-Stiftung ; CRC Health Group ; Canarie ; H2020 Marie Skłodowska-Curie Actions ; Multiple Sclerosis Scientific Research Foundation ; CERN ; Compute Canada ; Göran Gustafssons Stiftelser ; Natural Sciences and Engineering Research Council of Canada ; National Research Council Canada ; Canada Foundation for Innovation ; Science and Technology Facilities Council ; Leverhulme Trust ; European Research Council ; European Cooperation in Science and Technology ; Australian Research Council ; National Stroke Foundation ; Neurosurgical Research Foundation ; Helmholtz-Gemeinschaft ...