Abstract
A measurement of the W boson pair production cross section in proton-proton collisions at $\sqrt{s} = 8$ TeV is presented. The data collected with the CMS detector at the LHC correspond to an integrated luminosity of 19.4 fb$^ {-1}$. The $W^{+}W^{−}$ candidates are selected from events with two charged leptons, electrons or muons, and large missing transverse energy. The measured $W^{+}W^{−}$ cross section is 60.1± 0.9 (stat) ± 3.2 (exp) ± 3.1 (theo) ± 1.6 (lumi) pb = 60.1± 4.8 pb , consistent with the standard model prediction. The $W^{+}W^{−}$ cross sections are also measured in two different fiducial phase space regions. The normalized differential cross section is measured as a function of kinematic variables of the final-state charged leptons and compared with several perturbative QCD predictions. Limits on anomalous gauge couplings associated with dimension-six operators are also given in the framework of an effective field theory. The corresponding 95 % confidence level intervals are $-5.7< c_{WWW}/Λ^{2} < 5.9 TeV^{-2}, -11.4< c_{W}/Λ^2 < 5.4 TeV^{-2}, -29.2< c_{B}/Λ^2 < 23.9 TeV^{-2}$, in the HISZ basis.