ABSTRACTCONSTRAINTS ON MODELS FOR THE HIGGS BOSONWITH EXOTIC SPIN AND PARITYByEmily Hannah JohnsonThe production of a Higgs boson in association with a vector boson at the Tevatron offersa unique opportunity to study models for the Higgs boson with exotic spin J and parity Passignments. At the Tevatron the VH system is produced near threshold. Different JPassignments of the Higgs boson can be distinguished by examining the behavior of the crosssection near threshold. The relatively low backgrounds at the Tevatron compared to theLHC put us in a unique position to study the direct decay of the Higgs boson to fermions. Ifthe Higgs sector is more complex than predicted, studying the spin and parity of the Higgsboson in all decay modes is important. In this Thesis we will examine the WH → lνb ̄bproduction and decay mode using 9.7 fb−1 of data collected by the D0 experiment in anattempt to derive constraints on models containing exotic values for the spin and parity ofthe Higgs boson. In particular, we will examine models for a Higgs boson with JP = 0−and JP = 2+. We use a likelihood ratio to quantify the degree to which our data areincompatible with exotic JP predictions for a range of possible production rates. Assumingthe production cross section times branching ratio of the signals in the models consideredis equal to the standard model prediction, the WH → lνb ̄b mode alone is unable to rejecteither exotic model considered. We will also discuss the combination of the ZH → llb ̄b,WH → lνb ̄b, and VH → ννb ̄b production modes at the D0 experiment and with the CDFexperiment. When combining all three production modes at the D0 experiment we reject theJP = 0− and JP = 2+ hypotheses at the 97.6% CL and at the 99.0% CL, respectively, whenassuming the signal production cross section times branching ratio is equal to the standardmodel predicted value. When combining with the CDF experiment we reject the JP = 0−and JP = 2+ hypotheses with significances of 5.0 standard deviations and 4.9 standarddeviations, respectively.
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