The normalized distribution of Z->ee transverse momentum spectrum is measured in proton-proton collisions at center-of-mass energy of 7 TeV with the ATLAS detector. The results are based on a dataset corresponding to an integrated luminosity of 35 inverse pb collected in 2010.The major backgroundis from QCD processes and is studied by data-driven methods. A bin-by-bin unfolding method is used to correct for the detector acceptance and efficiency which is cross-checked with a regularized matrix unfolding method. A complete analysis of both theoretical and experimental uncertainties is also presented. The theoretical uncertainties arise fromQED and QCD corrections, which are estimated using Monte Carlo simulations. The experimental uncertainties arise from multiple sources with dominant ones being the electron identification, electron energy scale, and energy resolution. The measurement is compared to predictions of various MC event generators. The prediction of re-summed QCD combined with fixed order pQCD calculations is found to be in good agreement with data.
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Measurement of Z --> cc Transverse Momentum Distribution in Proton-proton Collisions ats = 7 TeV in the ATLAS Detector.