Constraints on off-shell Higgs boson production and the Higgs boson total width in Z Z → 4l and ZZ → 2l2ν final states using LHC proton–proton collision data at $\sqrt{s}$ = 13 TeV with the ATLAS detector.

A measurement of off-shell Higgs boson production in the ZZ → 4l and ZZ → 2l2ν decay channels, where l stands for either an electron or a muon, is performed using proton-proton collisions data at a center of mass energy of $\sqrt{s}$ = 13 TeV at LHC collected by the ATLAS experiment. An observed (expected) upper limit on the off-shell Higgs signal strength, defined as the event yield normalized to the Standard Model prediction, obtained at 95% confidence level (CL). Assuming the ratio of the Higgs boson couplings to the Standard Model predictions is independent of the momentum transfer of the Higgs production mechanism considered in the analysis, a combination with the on-shell signal-strength measurements yield an observed (expected) 95% CL upper limit on the Higgs boson total width.