Measurement of the transverse momentum distribution of Drell–Yan lepton pairs in proton–proton collisions at √s = 13 TeV with the ATLAS detector

This paper describes precision measurements of the transverse momentum p^ℓℓ_T (ℓ = e, µ) and of the angular variable φ^∗_η distributions of Drell–Yan lepton pairs in a mass range of 66–116 GeV. The analysis uses data from 36.1 fb⁻¹ of proton–proton collisions at a centre-of-mass energy of √s = 13 TeV collected by the ATLAS experiment at the LHC in 2015 and 2016. Measurements in electron-pair and muon-pair final states are performed in the same fiducial volumes, corrected for detector effects, and combined. Compared to previous measurements in proton–proton collisions at √s = 7 and 8 TeV, this new measurement probes perturbative QCD at a higher centre-of-mass energy with a different composition of initial states. It reaches a precision of 0.2% for the normalized spectra at low values of p^ℓℓ_T . The data are compared with different QCD predictions, where it is found that predictions based on resummation approaches can describe the full spectrum within uncertainties.