Measurement of electroweak production of two jets in association with a Z boson in proton–proton collisions at √s = 8TeV

Abstract

The purely electroweak (EW) cross section for the production of two jets in association with a Z boson, in proton–proton collisions at vs = 8TeV, is measured using data recorded by the CMS experiment at the CERN LHC, corresponding to an integrated luminosity of 19.7 fb-1. The electroweak cross section for the lljj final state (with l=e or µ and j representing the quarks produced in the hard interaction) in the kinematic region defined by Mll>50 GeV, Mjj>120 GeV, transverse momentum pTj>25 GeV, and pseudorapidity |?j|<5, is found to be sEW(lljj)=174±15(stat)±40(syst)\,fb, in agreement with the standard model prediction. The associated jet activity of the selected events is studied, in particular in a signal-enriched region of phase space, and the measurements are found to be in agreement with QCD predictions.