Measurements of $W^{+}{W}^{-}$ production cross-sections in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector

Abstract

Measurements of $W^{+}{W}^{-}\to e^{\pm }\nu {\mu }^{\mp }\nu$ production cross-sections are presented, providing a test of the predictions of perturbative quantum chromodynamics and the electroweak theory. The measurements are based on data from $pp$ collisions at $\sqrt{s}=13$ TeV recorded by the ATLAS detector at the Large Hadron Collider in 2015-2018, corresponding to an integrated luminosity of 140 fb${}^{-1}$. The number of events due to top-quark pair production, the largest background, is reduced by rejecting events containing jets with $b$-hadron decays. An improved methodology for estimating the remaining top-quark background enables a precise measurement of $W^{+}{W}^{-}$ cross-sections with no additional requirements on jets. The fiducial $W^{+}{W}^{-}$ cross-section is determined in a maximum-likelihood fit with an uncertainty of 3.1%. The measurement is extrapolated to the full phase space, resulting in a total $W^{+}{W}^{-}$ cross-section of $127\pm 4$ pb. Differential cross-sections are measured as a function of twelve observables that comprehensively describe the kinematics of $W^{+}{W}^{-}$ events. The measurements are compared with state-of-the-art theory calculations and excellent agreement with predictions is observed. A charge asymmetry in the lepton rapidity is observed as a function of the dilepton invariant mass, in agreement with the Standard Model expectation. A CP-odd observable is measured to be consistent with no CP violation. Limits on Standard Model effective field theory Wilson coefficients in the Warsaw basis are obtained from the differential cross-sections.

63 pages in total, author list starting page 46, 16 figures, 7 tables, published by JHEP. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2020-16/

References in corpus (21)

• The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations
• An Introduction to PYTHIA 8.2
• Matching NLO QCD computations with Parton Shower simulations: the POWHEG method
• Herwig++ Physics and Manual
• Parton distributions in the LHC era: MMHT 2014 PDFs
• A parton shower algorithm based on Catani-Seymour dipole factorisation
• Tuning PYTHIA 8.1: the Monash 2013 Tune
• Pileup subtraction using jet areas
• An NNLO subtraction formalism in hadron collisions and its application to Higgs boson production at the LHC
• Single-top Wt-channel production matched with parton showers using the POWHEG method
• Two-loop soft anomalous dimensions for single top quark associated production with a W- or H-
• Single-top hadroproduction in association with a W boson
• ZZ production at hadron colliders in NNLO QCD
• $W^{+}{W}^{-}$ production at hadron colliders in NNLO QCD
• Helicity Selection Rules and Non-Interference for BSM Amplitudes
• Anomalous Triple Gauge Couplings in the Effective Field Theory Approach at the LHC
• On the maximal use of Monte Carlo samples: re-weighting events at NLO accuracy
• Novel measurements of anomalous triple gauge couplings for the LHC
• NNLO QCD+NLO EW with MATRIX+OpenLoops: precise predictions for vector-boson pair production
• Transverse momentum resummation effects in W^+W^- measurements
• Boost Asymmetry of the diboson productions in pp collisions

Cited by in corpus (1)

• Prospects for observing the ${\eta }_t$ $\to$ $W^{+}{W}^{-}$ decay at the HL-LHC