Measurement of the four-lepton invariant mass spectrum in 13 TeV proton-proton collisions with the ATLAS detector
No Journal Information
The collaboration

Abstract (data abstract)
CERN-LHC. A measurement of the four-lepton invariant mass spectrum is made with the ATLAS detector, using an integrated luminosity of 36.1 fb$^{-1}$ of proton-proton collisions at $\sqrt{s}$=13 TeV delivered by the Large Hadron Collider. The differential cross section is measured for events containing two same-flavour opposite-sign lepton pairs, and is corrected for detector effects. It exhibits a rich structure, with different mass regions dominated in the Standard Model by single Z production, Higgs production, and Z boson pair production, and non-negligible interference effects at high invariant masses. In addition, there may be contributions from beyond-the-Standard Model (BSM) physics. The measurement is compared to state-of-the-art Standard Model calculations, which are found to be consistent with the data. These calculations are used to interpret the data in terms of $gg\to ZZ \to 4\ell$ and $Z \rightarrow 4\ell$ subprocesses, and to place constraints on a possible BSM contribution.