AION/Magis

Abstract:

We present a measurement of the cross section for W-boson production in association with jets in pp̄ collisions at s=1.96TeV. The analysis uses a data sample corresponding to an integrated luminosity of 320pb-1 collected with the CDF II detector. W bosons are identified in their electron decay channel and jets are reconstructed using a cone algorithm. For each W+≥n-jet sample (n=1-4) we measure the differential cross section dσ(pp̄→W+≥ n-jet)/dETnth-jet×B(W→eν) with respect to the transverse energy ET of the nth-highest ET jet above 20GeV, and the total cross section σ(pp̄→W+≥n-jet;ETnth-jet>25GeV)×B(W→eν), for a restricted W→eν decay phase space. The cross sections, corrected for all detector effects, can be directly compared to particle level W+jet(s) predictions. We present here comparisons to leading order and next-to-leading order predictions. © 2008 The American Physical Society.

Abstract:

We report on the results of a search for standard model Higgs bosons produced in association with W bosons from pp̄ collisions at s=1.96TeV. The search uses a data sample corresponding to approximately 1fb-1 of integrated luminosity. Events consistent with the W→ ν and H→bb̄ signature are selected by triggering on a high-pT electron or muon candidate and tagging one or two of the jet candidates as having originated from b quarks. A neural network filter rejects a fraction of tagged charm and light-flavor jets, increasing the b-jet purity in the sample. We observe no excess νbb̄ production beyond the background expectation, and we set 95% confidence level upper limits on the production cross section times branching fraction σ(pp̄→WH)Br(H→bb̄) ranging from 3.9 to 1.3 pb, for specific Higgs boson mass hypotheses in the range 110 to 150GeV/c2, respectively. © 2008 The American Physical Society.

Abstract:

In 5-dimensional models with gauge-Higgs unification, the F-term vacuum expectation value of the radion provides, in close analogy to the Giudice-Masiero mechanism, a natural source for the mu and B mu term. Both the leading order gauge theory lagrangian and the supersymmetric Chern-Simons term contain couplings to the radion superfield which can be used for this purpose. We analyse the basic features of this mechanism for mu term generation and provide an explicit example, based on a variation of the SU(6) gauge-Higgs unification model of Burdman and Nomura. This construction contains all the relevant features used in our generic analysis. More generally, we expect our mechanism to be relevant to many of the recently discussed orbifold GUT models derived from heterotic string theory. This provides an interesting way of testing high-scale physics via Higgs mass patterns accessible at the LHC.