Measurements of Drell-Yan and vector boson plus jet productions in ATLAS

The inclusive production of W and Z bosons as well the off-shell Z/gamma* production at hadron colliders provide a benchmark of our understanding of quantum chromodynamic (QCD) and electroweak (EW) processes. The measurement of their production cross-sections can be compared to theory calculations at NNLO QCD and have an impact on our knowledge of the parton densities of the proton. The production of heavy flavour in association with a W or Z boson represent important backgrounds to Higgs and BSM studies and are challenging to calculate in QCD. During the LHC Run 1, several precision measurements were performed by the ATLAS experiment using pp data at 7 TeV of integrated as well as differential cross sections. Comparisons are made to a diverse set of state-­of­the­-art NLO QCD calculations, some of which are interfaced to MC generators for parton showering and hadronization. Z+bb production probes the b­-quark production by high-­order QCD processes. Measurement of W+c production cross section has a unique sensitivity to the strange-­quark density, which is poorly known at low x. Measurements of the transverse momentum of Z/gamma* bosons and their decay lepton angular decorrelation with the phi* observable have been performed in different di-lepton invariant mass and rapidity regions . These measurements are sensitive to soft resummation effects and hard jet emissions for small and large momentum transfers, respectively, probing QCD in a unique way. The ratio of (W+jets) /(Z+jets) provides a precise test of QCD due to the large cancellations of theoretical and experimental uncertainties. In this talk, recent Run 2 results are also going to be presented. Measurements of the total inclusive production cross sections of $W \pm$ and Z bosons complemented with Z boson events produced in association with jets are discussed. These measurements were performed with pp collision data corresponding to an integrated luminosity of approximately 85 pb$^{−1}$, collected at √s = 13 TeV, showing agreement with theoretical calculations based on NNLO QCD