Measurement of W+W- production in association with one jet in proton-proton collisions at root s=8 TeV with the ATLAS detector
Abstract
The production of Wboson pairs in association with one jet in ppcollisions at SQUARE ROOTs=8TeVis studied using data corresponding to an integrated luminosity of 20.3fbMINUS SIGN 1collected by the ATLAS detector during 2012 at the CERN Large Hadron Collider. The cross section is measured in a fiducial phase-space region defined by the presence of exactly one electron and one muon, missing transverse momentum and exactly one jet with a transverse momentum above 25GeV and a pseudorapidity of |η| <4.5.
The leptons are required to have opposite electric charge and to pass transverse momentum and pseudorapidity requirements. The fiducial cross section is found to be σfid,1-jetWW=136 +-6 (stat)+-14 (syst)+-3 (lumi)fb.
In combination with a previous measurement restricted to leptonic final states with no associated jets, the fiducial cross section of WWproduction with zero or one jet is measured to be σfid,LESS-THAN OR EQUAL TO1-jetWW=511 +-9 (stat)+-26 (syst)+-10 (lumi)fb. The ratio of fiducial cross sections in final states with one and zero jets is determined to be 0.36 +-0.05.
Finally, a total cross section extrapolated from the fiducial measurement of WWproduction with zero or one associated jet is reported. The measurements are compared to theoretical predictions and found in good agreement.