Aad, G.G.AadAbbott, B.B.AbbottAbdallah, J.J.AbdallahAbdinov, O.O.AbdinovAben, R.R.AbenAbolins, M.M.AbolinsAbouZeid, O. S.O. S.AbouZeidAbramowicz, H.H.AbramowiczAbreu, H.H.AbreuAbreu, R.R.AbreuZwalinski, L.L.Zwalinski2012-09-272021-10-112012-09-272021-10-112011-07-20https://resolver.sub.uni-goettingen.de/purl?gro-2/90724This Letter presents a measurement of the W+W- production cross section in √s=7  TeV pp collisions by the ATLAS experiment, using 34  pb-1 of integrated luminosity produced by the Large Hadron Collider at CERN. Selecting events with two isolated leptons, each either an electron or a muon, 8 candidate events are observed with an expected background of 1.7±0.6 events. The measured cross section is 41-16+20(stat)±5(syst)±1(lumi)  pb, which is consistent with the standard model prediction of 44±3  pb calculated at next-to-leading order in QCD.18enCC BY 3.0https://creativecommons.org/licenses/by/3.0/proton-proton collisions;530journal_article10.1103/PhysRevLett.107.041802https://resolver.sub.uni-goettingen.de/purl?gs-1/7991openAccess