NLO QCD and electroweak corrections to WWW production at the LHC

Abstract

In this paper we calculate the next-to-leading order (NLO) QCD $[\mathcal{O}({\ensuremath{\alpha}}_{s}{\ensuremath{\alpha}}^{3})]$ and electroweak (EW) $[\mathcal{O}({\ensuremath{\alpha}}^{4})]$ corrections to the $WWW$ production at the LHC and deal with the subsequent leptonic decays from $W$ bosons by adopting an improved narrow-width approximation which takes into account the spin correlation and finite-width effects. The NLO QCD correction from the real jet radiation is discussed, which significantly enhances the production rate, particularly in the high-energy region. We also provide the integrated cross section for the $WWW$ production and various kinematic distributions of final products at the $\mathrm{QCD}+\mathrm{EW}$ NLO. We find that the convergence of the perturbative QCD description can be improved by applying a hard jet veto in the event selection, but this jet veto would introduce a new source of theoretical uncertainty. The pure NLO QCD relative correction to the integrated cross section for the ${W}^{+}{W}^{\ensuremath{-}}{W}^{+}$ production at the 14 TeV LHC is on the order of 30% in the jet-veto event selection scheme with ${p}_{T,\text{jet}}^{\mathrm{cut}}=50\text{ }\text{ }\mathrm{GeV}$, while the genuine NLO EW relative correction can reach about 15% in the inclusive event selection scheme. Our numerical results show that both the NLO QCD and NLO EW corrections should be taken into consideration in precision predictions.