Measurements of four-lepton production in pp collisions at √s=8 TeV with the ATLAS detector
The 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 co...
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| Formato: | JOUR |
| Acceso en línea: | http://hdl.handle.net/20.500.12110/paper_03702693_v753_n_p552_Aad |
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| Sumario: | The 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 μ gg =2.4±1.0 (stat.)±0.5 (syst.)±0.8 (theory). © 2015 CERN for the benefit of the ATLAS Collaboration |
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