Techniques utilized in the simulated altitude testing of a 2D-CD vectoring and reversing nozzle

Simulated altitude testing of a two-dimensional, convergent-divergent, thrust vectoring and reversing exhaust nozzle was accomplished. An important objective of this test was to develop test hardware and techniques to properly operate a vectoring and reversing nozzle within the confines of an altitude test facility. This report presents detailed information on the major test support systems utilized, the operational performance of the systems and the problems encountered, and test equipment improvements recommended for future tests. The most challenging support systems included the multi-axis thrust measurement system, vectored and reverse exhaust gas collection systems, and infrared temperature measurement systems used to evaluate and monitor the nozzle. The feasibility of testing a vectoring and reversing nozzle of this type in an altitude chamber was successfully demonstrated. Supporting systems performed as required. During reverser operation, engine exhaust gases were successfully captured and turned downstream. However, a small amount of exhaust gas spilled out the collector ducts' inlet openings when the reverser was opened more than 60 percent. The spillage did not affect engine or nozzle performance. The three infrared systems which viewed the nozzle through the exhaust collection system worked remarkably well considering the harsh environment

New hypersonic facility capability at NASA Lewis Research Center

Four facility activities are underway at NASA Lewis Research Center to develop new hypersonic propulsion test capability. Two of these efforts consist of upgrades to existing operational facilities. The other two activities will reactivate facilities that have been in a standby condition for over 15 years. These four activities are discussed and the new test facilities NASA Lewis will have in place to support evolving high speed research programs are described

Neutrino-Lepton Masses, Zee Scalars and Muon g-2

Evidence for neutrino oscillations is pointing to the existence of tiny but finite neutrino masses. Such masses may be naturally generated via radiative corrections in models such as the Zee model where a singlet Zee-scalar plays a key role. We minimally extend the Zee model by including a right-handed singlet neutrino \nu_R. The radiative Zee-mechanism can be protected by a simple U(1)_X symmetry involving only the \nu_R and a Zee-scalar. We further construct a class of models with a single horizontal U(1)_FN (a la Frogatt-Nielsen) such that the mass patterns of the neutrinos and leptons are naturally explained. We then analyze the muon anomalous magnetic moment (g-2) and the flavor changing \mu --> e\gamma decay. The \nu_R interaction in our minimal extension is found to induce the BNL g-2 anomaly, with a light charged Zee-scalar of mass 100-300 GeV.Comment: Version for Phys. Rev. Lett. (typos corrected, minor refinements

Probing color-singlet exchange in Z+2Z+2-jet events at the LHC

The purely electroweak process $qq\to qqZ$ (via $t$-channel $\gamma/Z$ or $W$ exchange) provides a copious and fairly clean source of color-singlet exchange events in $pp$ collisions at the LHC. A judicious choice of phase-space region allows the suppression of QCD backgrounds to the level of the signal. The color-singlet-exchange signal can be distinguished from QCD backgrounds by the radiation patterns of additional minijets in individual events. A rapidity-gap trigger at the minijet level substantially enhances the signal versus the background. Analogous features of weak boson scattering events make $Z+2$-jet events at the LHC an ideal laboratory for investigation of the soft-jet activity expected in weak-boson scattering events.Comment: 24 pages (with 7 embedded figures), Revtex, uses epsf.sty. Z-compressed postscript version also available at http://phenom.physics.wisc.edu/pub/preprints/1996/madph-96-943.ps.Z or at ftp://phenom.physics.wisc.edu/pub/preprints/1996/madph-96-943.ps.

Composite Higgs Sketch

The coupling of a composite Higgs to the standard model fields can deviate substantially from the standard model values. In this case perturbative unitarity might break down before the scale of compositeness is reached, which would suggest that additional composites should lie well below this scale. In this paper we account for the presence of an additional spin 1 custodial triplet of rhos. We examine the implications of requiring perturbative unitarity up to the compositeness scale and find that one has to be close to saturating certain unitarity sum rules involving the Higgs and the rho couplings. Given these restrictions on the parameter space we investigate the main phenomenological consequences of the spin 1 triplet. We find that they can substantially enhance the Higgs di-photon rate at the LHC even with a reduced Higgs coupling to gauge bosons. The main existing LHC bounds arise from di-boson searches, especially in the experimentally clean channel where the charged rhos decay to a W-boson and a Z, which then decay leptonically. We find that a large range of interesting parameter space with 700 GeV < m(rho) < 2 TeV is currently experimentally viable.Comment: 37 pages, 12 figures; v4: sum rule corrected, conclusions unchange

The radiation-matter transition in Jordan-Brans-Dicke theory

We study the transition from radiation domination to matter domination in Jordan-Brans-Dicke theory, in particular examining how the Hubble length at equality depends on the coupling parameter $\omega$. We consider the prospects for using high-accuracy microwave anisotropy and large-scale structure data to constrain $\omega$ more strongly than by conventional solar system gravity experiments.Comment: 4 pages RevTeX file with one figures incorporated (uses RevTeX and epsf

Next-to-leading order QCD predictions for W+2j and Z+2j production at the CERN LHC

We present cross sections and differential distributions for QCD radiative corrections to the QCD processes pp -> W+2j and pp -> Z+2j at the CERN LHC. Calculations are performed with the Monte Carlo program MCFM. Cross section dependence on the renormalization and factorization scales is greatly reduced, except for the heavy-flavor case of Wbb~, which has new features at next-to-leading order at the LHC. We also present cross sections for Wbb~ and Z+2j in kinematic configurations relevant for Higgs boson searches.Comment: 24p, PRD version, ref's corrected, add. paragraph to explain pTmiss fi

Engineering the Redox Potential over a Wide Range within a New Class of FeS Proteins

Abstract: MitoNEET is a newly discovered mitochondrial protein and a target of the TZD class of antidiabetes drugs. MitoNEET is homodimeric with each protomer binding a [2Fe-2S] center through a rare 3-Cys and 1-His coordination geometry. Both the fold and the coordination of the [2Fe-2S] centers suggest that it could have novel properties compared to other known [2Fe-2S] proteins. We tested the robustness of mitoNEET to mutation and the range over which the redox potential (EM) could be tuned. We found that the protein could tolerate an array of mutations that modified the EM of the [2Fe-2S] center over a range of ∼700 mV, which is the largest EM range engineered in an FeS protein and, importantly, spans the cellular redox range (+200 to-300 mV). These properties make mitoNEET potentially useful for both physiological studies and industrial applications as a stable, water-soluble, redox agent