Measurement of electroweak production of two jets in association with a Z boson in proton-proton collisions at $\sqrt{s}=13~\mathrm{TeV}$

A measurement of the electroweak (EW) production of two jets in association with a Z boson in proton-proton collision at $\sqrt{s}=13~\mathrm{TeV}$ is presented, based on data recorded by the CMS experiment at the LHC corresponding to an integrated luminosity of $35.9~\mathrm{fb}^{-1}$. The measurement is performed using the $\ell\ell$jj final state (with $\ell =$e or $\mu$ and j representing the quarks produced in the hard interaction) in the kinematic region defined by $M_{\ell\ell} >50~\mathrm{GeV}$, $M_\mathrm{jj} >120~\mathrm{GeV}$, transverse momentum $p_\mathrm{T j} > 25~\mathrm{GeV}$. The cross section of the process is found to be $\sigma_\mathrm{EW}(\ell\ell\mathrm{jj})= 552 \pm 19(\mathrm{stat})\pm 55(\mathrm{syst})~\mathrm{fb}$, in agreement with leading order standard model predictions. The associated jet activity of events in a signal-enriched region is also studied, and the measurements are found to be in agreement with QCD predictions.