Measurement of the WW Cross Section in 7 TeV pp Collisions with the ATLAS Detector

We report a measurement of the WW production cross section in pp collisions at $sqrt s $ = 7~TeV. The WW leptonic decay channels are analyzed using data corresponding to 1.02/fb of integrated luminosity collected by the ATLAS detector during 2011 at the CERN Large Hadron Collider. With 414 observed WW candidate events and an estimated background of 170$pm$28 events, the measured WW production cross section is $48.2 pm 4.0 { m(stat)} pm 6.4 { m(syst)} pm 1.8 { m(lumi)}$ pb, in agreement with the Standard Model NLO prediction of 46 $pm$ 3~pb.