Measurement of W and Z boson production with the ATLAS detector

Abstract

The production of the W ± and Z bosons at the Large Hadron Collider is a sensitive test of the Standard Model. Precise total and differential cross-sect ion measurements by the ATLAS experiment are presented. The results are compared to Monte Carlo simulations and to predictions computed at up to next-to-next-to-leading order quantum-chromo-dynamics (QCD) for different sets of parton distribution functions. A measurement of angular correlations in Drell-Yan lepton pairs for neutral current process via the φ ∗ η observable is also presented. This variable probes the same physics as the Z/γ ∗ boson transverse momentum (pT) with a better experimental resolution. The measurement using φ ∗ η and the direct measurement of vector boson pT are compared to predictions based on QCD calculations and predictions from different Monte Carlo event generators. The production of jets in association with a W or Z boson is an important process to study QCD in a multi-scale environment. The cross sections, differen tial in several kinematics variables, have been measured up to high jet multiplicities and compared to high-order QCD calculations. The exclusive processes of W+b and W+c production have also been measured with high precision and cross sections are compared to state-of-the-art high-o rder QCD calculations.