Differential and double-differential distributions of kinematic variables of leptons from decays of top-quark pairs (t (t) over bar) 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 root s = 13TeV and correspond to an integrated luminosity of 140 fb(-1). The measurements use events containing an oppositely charged e mu 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 p(T) distributions is obtained by reweighting the t (t) over bar sample so as to reproduce the top-quark p(T) 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 besigma(t (t) over bar) = 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.

Aad, G., Abbott, B., Abbott, D.C., Abeling, K., Abidi, S.H., Aboulhorma, A., et al. (2023). Inclusive and differential cross-sections for dilepton tt¯ production measured in √s = 13 TeV pp collisions with the ATLAS detector. JOURNAL OF HIGH ENERGY PHYSICS, 2023(7), 0-77 [10.1007/JHEP07(2023)141].

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

Alberghi, G. L.;Alfonsi, F.;Bindi, M.;Boscherini, D.;Cabras, G.;Carratta, G.;Cavalli, N.;Clissa, L.;De Castro, S.;Fabbri, F.;Fabbri, L.;Franchini, M.;Gabrielli, A.;Lasagni Manghi, F.;Massa, L.;