The cross-section for the production of two jets in association with a leptonically decaying Z boson (Zjj) is measured in proton–proton collisions at a centre-of-mass energy of 13 TeV, using data recorded with the ATLAS detector at the Large Hadron Collider, corresponding to an integrated luminosity of 3.2 fb−1. The electroweak Zjj cross-section is extracted in a fiducial region chosen to enhance the electroweak contribution relative to the dominant Drell–Yan Zjj process, which is constrained using a data-driven approach. The measured fiducial electroweak cross-section is σEWZjj = 119±16(stat.)±20(syst.)±2(lumi.) fb for dijet invariant mass greater than 250 GeV, and 34.2±5.8(stat.)±5.5(syst.)±0.7(lumi.) fb for dijet invariant mass greater than 1 TeV. Standard Model predictions are in agreement with the measurements. The inclusive Zjj cross-section is also measured in six different fiducial regions with varying contributions from electroweak and Drell–Yan Zjj production.

Aaboud, M., Aad, G., Abbott, B., Abdinov, O., Abeloos, B., Abidi, S.H., et al. (2017). Measurement of the cross-section for electroweak production of dijets in association with a Z boson in pp collisions at s=13 TeV with the ATLAS detector. PHYSICS LETTERS. SECTION B, 775, 206-228 [10.1016/j.physletb.2017.10.040].

Measurement of the cross-section for electroweak production of dijets in association with a Z boson in pp collisions at s=13 TeV with the ATLAS detector

Ceradini F.;Di Micco B.;Di Nardo R.;Orestano D.;Petrucci F.;Salamanna G.;