Determining the Jet Energy Scale Uncertainty in the ATLAS detector

Using jets from proton-proton collisions at a centre of mass energy of s = 7 TeV measured with the ATLAS detector at the LHC the Jet Energy Scale and its systematic uncertainty have been determined. A Jet Energy Scale systematic uncertainty between 2-4% for jet pT >20GeV in the pseudo-rapidity region up to |η|=4.5 has been obtained. This uncertainty was derived from a combination of systematic variations in Monte Carlo simulations and single hadron response measurements performed in-situ and using test beam data. The uncertainty is confirmed using in-situ methods where a well measured reference object is balanced against the jet.