Study of associated WH production with H -> WW* in the 3 leptons final state

In order to evaluate the physics potential of the CMS detector, the WH associated production of a Higgs boson decaying into a W pair is studied. Performance of the data acquisition and the sophisticated trigger system, particle identification and event reconstruction are investigated by performing a detailed analysis on simulated data. Three-lepton final states are shown to provide interesting possibilities. For an integrated luminosity of 100fb^-1, a potential signal significance of more than 5 sigma is obtained in the mass interval between 155 and 178 GeV/c^2. The corresponding precision on the Higgs boson mass and partial decay width into W pairs are evaluated. This channel also provides one of the very few possible avenues towards the discovery of a fermiophobic Higgs boson below 180 GeV/c^2.