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

Abstract

We consider QCD radiative corrections to W + W − production at the LHC and present the first fully differential predictions for this process at next-to-next-to-leading order (NNLO) in perturbation theory. Our computation consistently includes the leptonic decays of the W bosons, taking into account spin correlations, off-shell effects and nonresonant contributions. Detailed predictions are presented for the different-flavour channel pp → µ + e − ν µνe + X at √ s = 8 and 13 TeV. In particular, we discuss fiducial cross sections and distributions in the presence of standard selection cuts used in experimental W + W − and H → W + W − analyses at the LHC. The inclusive W + W − cross section receives large NNLO corrections, and, due to the presence of a jet veto, typical fiducial cuts have a sizeable influence on the behaviour of the perturbative expansion. The availability of differential NNLO predictions, both for inclusive and fiducial observables, will play an important role in the rich physics programme that is based on precision studies of W + W − signatures at the LHC.

Multiboson interactions at the LHC

“…For diboson production, the state of the art QCD calculation is NNLO for W + W − Grazzini et al, 2016a), W ± γ (Denner et al, 2015;Grazzini et al, 2015a), Grazzini et al, 2015a) and γγ (Campbell et al, 2016). There has been recent rapid progress on this front using q T subtraction techniques and in the near future public codes, such as MATRIX (Wiesemann et al, 2016), should be available to automate event generation.…”

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

“…As a first step beyond NLO QCD, the NLO predictions were matched to parton-shower programs without [10] and including [11][12][13][14][15] leptonic W decays. Recently, complete next-to-next-to-leading order (NNLO) QCD predictions were presented [16,17] after a continuous effort over several years [18,19]. Pushing up the inclusive WW cross section at the LHC by about 9% (12%) at a CM energy of 7 (14) TeV with respect to NLO QCD, the NNLO QCD prediction, which has a residual perturbative uncertainty of ∼ 3% in the qq channel, widely relaxed a tension between theory predictions for inclusive cross sections and LHC data.…”

Resummation of jet veto logarithms at N3LLa+NNLO for WDawson1, Jaiswal2, Li3 et al. 2016Phys. Rev. D281320View full textAdd to dashboardCite

“…The availability of two-loop matrix elements for W + W − production [28,29] has made possible NNLO predictions for the W + W − production total cross section [1] and differ-ential distributions [2]. Furthermore, it is possible to extend both transverse momentum resummation [30] to NNLL +NNLO (equivalent to NNLL'+NNLO in our log-counting convention) and jet-veto resummation calculations to partial N 3 LL+NNLO.…”

“…Finally, the result forÎ (2) qq , describing the quark beam function corresponding to the PDF of an anti-quark or a quark of a different flavor, iŝ…”

“…The h → W + W − signal has the standard model (SM) W + W − production as an irreducible background. All of these considerations make it crucial to understand electroweak W + W − production as accurately as possible [1][2][3][4][5][6].…”