W+W− production at the LHC: fiducial cross sections and distributions in NNLO QCD

TLDR: In this article, the first fully differential calculation for W ± Z production in hadron collisions up to next-to-nextto-leading order (NNLO) in QCD perturbation theory is reported.

Abstract: We report on the first fully differential calculation for W ± Z production in hadron collisions up to next-to-next-to-leading order (NNLO) in QCD perturbation theory. Leptonic decays of the W and Z bosons are consistently taken into account, i.e. we include all resonant and non-resonant diagrams that contribute to the process pp → l ′± ν l ′ l + l − +X both in the same-flavour (l ′ = l) and the different-flavour (l ′ ≠ l) channel. Fiducial cross sections and distributions are presented in the presence of standard selection cuts applied in the experimental W ± Z analyses by ATLAS and CMS at centre-of-mass energies of 8 and 13 TeV. As previously shown for the inclusive cross section, NNLO corrections increase the NNLO result by about 10%, thereby leading to an improved agreement with experimental data. The importance of NNLO accurate predictions is also shown in the case of new-physics scenarios, where, especially in high-p T categories, their impact can reach $$ \mathcal{O}\left(20\%\right) $$ . The availability of differential NNLO predictions will play a crucial role in the rich physics programme that is based on precision studies of W ± Z signatures at the LHC.