Measurement of the WZ and ZZ Production Cross Sections Using the WZ →3l + MET and ZZ → 4l Channels


Measuring heavy diboson production in pp collisions is a way of probing the structure of the electroweak sector, and provides milestones on the way to sensitivity to rare processes such as Higgs boson production. We measure WZ and ZZ production in the three- and four-lepton channels. Using 6 fb^-1 of data collected by the CDF experiment in pp collisions at 1.96 TeV we reconstruct 50 WZ → 3l + ν candidate events, where l is a charged lepton, and measure the ratio σ(pp → WZ)/ σ(pp → Z) = (5.5 ± 0.9) x 10^-4 Using 4 ZZ → 4l candidate events with M(ZZ) < 300 GeV we measure the ratio of the ZZ production cross section to the inclusive Z production cross section σ(pp → ZZ)/ σ(pp → Z) = (2.3 +1.5-0.9(stat) ±0.3 (syst)) x 10^-4 Taking the theoretical value of σ (Z⁰→ l⁺l) pb we determine the diboson production cross sections σ(pp → WZ) = (4.1 ± 0.7) pb and σ(pp → ZZ ) = (1.7 +1.2-0.7 (stat) ± 0.2 (syst)) pb Normalizing to the inclusive Z production cross section reduces the systematic uncertainties on the measured cross sections.
Public Note
Public Note: CDF 10238
Plots

Public Note: CDF 10238