Performance of the Jet Energy Calibration at ATLAS using pT Balance in Z + Jet Events

A precision measurement of the jet energy scale is essential for the success of the ATLAS experiment. This thesis investigates the suitability of pT balancing in Z + Jet events as an in situ technique for assessing the performance of the jet energy calibration. While the technique is shown to have a kinematic bias in the region pT_Z < 60 GeV/c, it is useful for studying jet performance at higher pT_Z . The effects of background processes and signal selection criteria on the pT balance are studied. This study also investigates the performance of jet reconstruction with various jet input constituents, jet algorithms and sizes, and jet calibration schemes.