Search for the Higgs boson in the H -> WW(*) -> lvlv channel using multivariate analysis techniques
LE3 .A278 2013
Bachelor of Science
A comparison of di erent analysis techniques used in the search for the SM Higgs boson in the H ! WW( ) ! ` ` + 2-jets channel is conducted using the signal sensitivity, Ssig = Nsig= p Nbg, as the gure of merit. The two analysis techniques compared are the cut-based analysis that is currently employed by the ATLAS col- laboration and the novel application of the Matrix Element Method, a multivariate analysis (MVA) technique. Although the Matrix Element Method has o ered im- proved sensitivity in other searches in the past, no improvement in signal sensitivity is observed in this study over the baseline cut-based analysis. The cut-based analysis produces a signal sensitivity Ssig = 405:25 4:99%(stat.) while the Matrix Element Method yields a signal sensitivity Ssig = 402:57 5:00%(stat.). However, it is believed that this null result is explained by the application of a b-tag veto, and in fact, further improvements by the HSG3 VBF MVA Group on the Matrix Element Analysis in this channel have yielded a 286% increase in signal sensitivity, veri ying the ME Method is capable of improving a search for the Higgs boson.
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