Next-to-leading-order electroweak corrections to pp → W+W- → 4 leptons at the LHC

We present results of the first calculation of next-to-leading-order electroweak corrections to W-boson pair production at the LHC that fully takes into account leptonic W-boson decays and off-shell effects. Employing realistic event selections, we discuss the corrections in situations that are typical for the study of W-boson pairs as a signal process or of Riggs-boson decays H -> WW*, to which NV-boson pair production represents an irreducible background. In particular, we compare the full off-shell results, obtained treating the NV-boson resonances in the complex-mass scheme, to previous results in the so-called double-pole approximation, which is based on an expansion of the loop amplitudes about the W resonance poles. At small and intermediate scales, i.e. in particular in angular and rapidity distributions, the two approaches show the expected agreement at the level of fractions of a percent, but larger differences appear in the TeV range. For transverse-momentum distributions, the differences can even exceed the 10% level in the TeV range where background diagrams with one instead of two resonant W bosons gain in importance because of recoil effects.