Clark, Brian LeeFranklin, MelissaHuth, JohnIppolito, ValerioLazovich, TomoLopez Mateos, DavidMercurio, KevinMorii, MasahiroSpearman, WilliamSun, SiyuanTolley, EmmaTuna, AlexanderYen, AndyZambito, Stefano2017-06-202016ATLAS Collaboration. 2016. “Measurements of four-lepton production in pp collisions at s√= 8 TeV with the ATLAS detector.” Physics Letters B 753 (February): 552–572. doi:10.1016/j.physletb.2015.12.048.0370-2693http://nrs.harvard.edu/urn-3:HUL.InstRepos:33058571The four-lepton (4ℓ, ℓ=e,μ) production cross section is measured in the mass range from 80 to 1000 GeV using 20.3 fb−1 of data in pp collisions at s√=8 TeV collected with the ATLAS detector at the LHC. The 4ℓ events are produced in the decays of resonant Z and Higgs bosons and the non-resonant ZZ continuum originating from qq¯, gg, and qg initial states. A total of 476 signal candidate events are observed with a background expectation of 26.2±3.6 events, enabling the measurement of the integrated cross section and the differential cross section as a function of the invariant mass and transverse momentum of the four-lepton system. In the mass range above 180 GeV, assuming the theoretical constraint on the qq¯ production cross section calculated with perturbative NNLO QCD and NLO electroweak corrections, the signal strength of the gluon-fusion component relative to its leading-order prediction is determined to be μgg=2.4±1.0(stat.)±0.5(syst.)±0.8(theory).en-USJournal Article2017-06-2010.1016/j.physletb.2015.12.048