Search for the standard model Higgs boson in ℓν+jets final states in 9.7 fb^-1 of pp̄ collisions with the D0 detector

We present, in detail, a search for the standard model Higgs boson, H, in final states with a charged lepton (electron or muon), missing energy, and two or more jets in data corresponding to 9.7 fb^-1 of integrated luminosity collected at a center-of-mass energy of √s=1.96 TeV with the D0 detector at the Fermilab Tevatron pp̄ Collider. The search uses b-jet identification to categorize events for improved signal versus background separation and is sensitive to associated production of the H with a W boson, WH→ℓνbb̄; gluon fusion with the Higgs decaying to W-boson pairs, H→WW→ℓνjj; and associated production with a vector boson where the Higgs decays to W-boson pairs, VH→VWW→ℓνjjjj production (where V=W or Z). We observe good agreement between data and expected background. We test our method by measuring WZ and ZZ production with Z→bb̄ and find production rates consistent with the standard model prediction. For a Higgs boson mass of 125 GeV, we set a 95% C.L. upper limit on the production of a standard model Higgs boson of 5. 8×σ_SM, where σ_SM is the standard model Higgs boson production cross section, while the expected limit is 4.7×σ_SM. We also interpret the data considering models with fourth generation fermions, or a fermiophobic Higgs boson.