This seminar presents a precise measurement of the production properties of the Z-boson in the full phase space of the decay leptons, based on 8 TeV pp collision data collected by the ATLAS experiment in 2012. The double-differential cross-section distributions in Z-boson transverse momentum and rapidity are measured in the pole region. In a novel approach, the measured Z transverse momentum is used to determine the strong coupling constant. The analysis uses state-of-the-art predictions at third order accuracy in perturbative QCD, supplemented by resummation of logarithmically-enhanced contributions in the small transverse-momentum region of the lepton pairs. The extracted alphaS(mZ) result is the most precise single measurement to date.
Refreshments will be served at 10:30
Michelangelo Mangano, Jan Fiete Grosse-Oetringhaus and Pedro Silva