Measurements of the hadronic activity and the electroweak production in events with a Z boson and two jets in proton-proton collisions with the CMS experiment

The observation of the electroweak production of a Z boson with two jets in pp collisions at $\sqrt{s} = 8$ TeV with the CMS experiment at the CERN LHC is presented, based on a data sample with an integrated luminosity of 19.7 fb$^{-1}$. The cross section measurement, combining the muon and electron channels, is in agreement with the theoretical expectations. Radiation patterns of selected Z plus two jets events, and the hadronic activity in the rapidity interval between the jets are also measured. These results are of substantial importance in the more general study of vector boson fusion processes, of relevance for Higgs boson searches and for measurements of electroweak gauge couplings and vector boson scattering.