Measurement of the WZ production cross section and limits on anomalous triple gauge couplings in proton-proton collisions at √s = 7 TeV with the ATLAS detector

This Letter presents a measurement of W± Z production in 1.02 fb−1 of pp collision data at √s = 7 TeV collected by the ATLAS experiment in 2011. Doubly leptonic decay events are selected with electrons, muons and missing transverse momentum in the final state. In total 71 candidates are observed, with a background expectation of 12.1 ± 1.4(stat.)+4.1−2.0(syst.) events. The total cross section for W± Z production for Z/γ ∗ masses within the range 66 GeV to 116 GeV is determined to be σtotWZ = 20.5+3.1−2.8(stat.)+1.4−1.3(syst.)+0.9−0.8(lumi.) pb, which is consistent with the Standard Model expectation of 17.3+1.3-0.8 pb. Limits on anomalous triple gauge boson couplings are extracted.