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Title: Search for the standard model Higgs boson in association with a W boson at D0.

I present a search for the standard model Higgs boson, H, produced in association with a W boson in data events containing a charged lepton (electron or muon), missing energy, and two or three jets. The data analysed correspond to 9.7 fb-1 of integrated luminosity collected at a center-of-momentum energy of √s = 1.96 TeV with the D0 detector at the Fermilab Tevatron p$$\bar{p}$$ collider. This search uses algorithms to identify the signature of bottom quark production and multivariate techniques to improve the purity of H → b$$\bar{b}$$ production. We validate our methodology by measuring WZ and ZZ production with Z → b$$\bar{b}$$ and find production rates consistent with the standard model prediction. For a Higgs boson mass of 125 GeV, we determine a 95% C.L. upper limit on the production of a standard model Higgs boson of 4.8 times the standard model Higgs boson production cross section, while the expected limit is 4.7 times the standard model production cross section. I also present a novel method for improving the energy resolution for charged particles within hadronic signatures. This is achieved by replacing the calorimeter energy measurement for charged particles within a hadronic signature with the tracking momentum measurement. This technique leads to a ~ 20% improvement in the jet energy resolution, which yields a ~ 7% improvement in the reconstructed dijet mass width for H → b$$\bar{b}$$ events. The improved energy calculation leads to a ~ 5% improvement in our expected 95% C.L. upper limit on the Higgs boson production cross section.
Authors:
 [1]
  1. Michigan State Univ., East Lansing, MI (United States)
Publication Date:
OSTI Identifier:
1128454
Report Number(s):
FERMILAB-THESIS--2013-18
DOE Contract Number:
AC02-07CH11359
Resource Type:
Thesis/Dissertation
Research Org:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS