Evidence for $$\text {W}\text {W}$$WW production from double-parton interactions in proton–proton collisions at $$\sqrt{s} = 13 \,\text {TeV} $$s=13TeV

Abstract

Abstract A search for $$\text {W}\text {W}$$WW production from double-parton scattering processes using same-charge electron-muon and dimuon events is reported, based on proton-proton collision data collected at a center-of-mass energy of $$13\,\text {TeV} $$13TeV. The analyzed data set corresponds to an integrated luminosity of $$77.4{\,\text {fb}^{-1}} $$77.4fb-1, collected using the CMS detector at the LHC in 2016 and 2017. Multivariate classifiers are used to discriminate between the signal and the dominant background processes. A maximum likelihood fit is performed to extract the signal cross section. This leads to the first evidence for $$\text {W}\text {W}$$WW production via double-parton scattering, with a significance of 3.9 standard deviations. The measured inclusive cross section is $$1.41\pm 0.28\,\text {(stat)} \pm 0.28\,\text {(syst)} \,\text {pb} $$1.41±0.28(stat)±0.28(syst)pb.