Electroweak production of Z bosons with forward-backward jets

The first measurement of the electroweak production cross section of a Z boson with two jets (EWK~Zjj) in proton-proton collisions at $\sqrt{s}=7$~TeV is discussed. Proton-proton data, recorded by the CMS experiment at the LHC and corresponding to an integrated luminosity of 5~fb$^{-1}$, is used to measure $\sigma({\rm EWK~Zjj})=154\pm24_{\rm stat}\pm 46_{\rm exp}\pm 27_{\rm th}\pm3_{\rm lumi}$~fb in agreement with the standard model prediction. The result establishes the basis for the more general study of vector boson fusion processes: Higgs boson searches, anomalous electroweak gauge couplings and the scattering of vector bosons.