Sensitivity study for the Higgs Boson decay H → WW(*) → l νl' ν' with the ATLAS Detector

One of the most exciting prospects for the LHC, is the discovery of the Higgs Boson. The search for the decay H → WW(*) → l νl' ν', with l,l'=e,μ, has large sensitivity to a Standard Model Higgs Boson in the mass range 130 < MH<200 GeV. The sensitivity of the ATLAS detector with a center of mass energy of 10 TeV and an integrated luminosity of 200 pb-1, based on a realistic full detector simulation, is presented. These studies separate the events according to the number of hadronic jets in the final state (0,1,2), and the cuts to apply vary accordingly, exploiting the differences between signal and backgrounds which are specific of every jet multiplicity. Different data-driven methods, used to reduce the dependence on Monte Carlo simulations for background estimation, are also discussed. Finally, the expected sensitivity for ATLAS to exclude a Standard Model Higgs Boson, at 95% confidence level, with 200 pb-1, is shown.