Prospects for the Measurement of the Higgs CP Structure at ATLAS in Higgs to Four Lepton Decays

A Monte Carlo simulation is performed of Higgs decays in the H->ZZ->4l channel at ATLAS. Decay parameters are varied in order to model Higgs decays of differing CP states. A full analysis is performed, including trigger and background studies. Using various angular distributions as observables it is found that ATLAS should be able to exclude an anomalous CP odd coupling at 50 fb^-1 and an anomalous CP even coupling at 100 fb^-1. The CP violating case studied could not be excluded.