Study of the Higgs Boson Produced in Association with a Weak Boson and Decaying to WW* with a Same Sign Dilepton and Jets Final State in $\sqrt{s}$ =8 TeV pp Collisions with the ATLAS Detector at the LHC

The research described in this thesis is aimed at studying production of a Higgs boson in association with a W boson, in the H → W W ∗ decay mode, using 20 fb −1 of 8 TeV data collected in 2012. The specific final state studied in this thesis has the associated W boson and one of the W bosons from the Higgs decaying leptonically, while the last W boson decays hadronically, giving two leptons, jets, and missing transverse energy as the final state signature in the ATLAS detector. The two leptons are required to have the same sign charge in order to suppress the many Standard Model background processes with oppositely charged di-lepton final states. The most important backgrounds are the W Z process where a lepton is not correctly identified, the W +jets process where a jet is misidentified as a lepton, and the W γ process where a photon converts and is incorrectly identified as a lepton. The ultimate goal of the analysis is to measure the rate of W H production.