The Search for the Standard Model Higgs boson in the Four Lepton Final State with the ATLAS Detector.

The search for the Standard Model (SM) Higgs boson is one of the main objectives of the experiments at the Large Hadron Collider (LHC). The decay mode leading to a four lepton (electron/muon) final state provides an experimentally clean signature and one of the more promising channels for its discovery. The sensitivity of the ATLAS detector to a SM Higgs boson in the four lepton final state is presented for a range of masses, from 120 GeV to 600 GeV. Analysis strategies for selecting signal and rejecting backgrounds are described and methods for extracting backgrounds and estimating systematic uncertainties from data are discussed. The overall sensitivity of the ATLAS detector to a SM Higgs boson, after a combination with other decay channels, is also presented.