Lone Higgs at the LHC

We address the possible scenario that the Large Hadron Collider (LHC) discovers only a Higgs boson after 10 fb^{-1} of operation, and attempt to identify this Higgs boson as that of the Standard Model (SM), the minimal universal extra dimension model (MUED), the littlest Higgs model with T-parity (LHT), or the minimal supersymmetric Standard Model (MSSM), using only the measurement of the product of gluon-fusion production cross section and the di-photon branching ratio. In MUED, by decoupling any new physics sufficiently to evade the discovery reach at the LHC, the deviation of the signal from the SM is not statistically significant. However, in LHT and MSSM, it is possible to have a significant deviation in the signal that is consistent with this "lone Higgs scenario", and, in the case of a very large suppression, we can distinguish MSSM and LHT before the discovery of any new resonances. Starting with the lone Higgs scenario and the deviation in this measurement from the Standard Model prediction (whether or not statistically significant), we offer tests that may discriminate the models and search strategies of discovering new physics signatures with increasing integrated luminosity.Comment: 32 pages, 25 figures, PRD versio

Materials Design - Towards a Functionally Graded Electrical Conductor

In this study, we discuss functionally graded (FG) materials as pulsed electrical conductors. These conductors can be designed to be more efficient and longer lasting by applying numerical modeling tools. One focus is on limiting the thermal fatigue damage in conductors caused by very high temperatures that develop during pulse heating. We have quantified the effect of various grading functions on the pulsed Joule heating generated and the peak temperature experienced in the conductors of an electromagnetic launcher by using a 1D numerical code and a state of the art 3D coupled finite element code, EMAP3D. Because FG materials incorporate applications-tailored compositions, structures, and dimensions, smoothly graded properties in lateral and longitudinal cross sections are obtainable. The Solid Freeform Fabrication (SFF) processing approach allows for architectures with a series of important features. These features include the selective use of high efficiency conducting materials in the core, preconditioned conductor/structure interfaces, and built-in features for enhanced cooling where necessary.Mechanical Engineerin

Insights into antibody catalysis: Structure of an oxygenation catalyst at 1.9-Å resolution

The x-ray crystal structures of the sulfide oxidase antibody 28B4 and of antibody 28B4 complexed with hapten have been solved at 2.2-Å and 1.9-Å resolution, respectively. To our knowledge, these structures are the highest resolution catalytic antibody structures to date and provide insight into the molecular mechanism of this antibody-catalyzed monooxygenation reaction. Specifically, the data suggest that entropic restriction plays a fundamental role in catalysis through the precise alignment of the thioether substrate and oxidant. The antibody active site also stabilizes developing charge on both sulfur and periodate in the transition state via cation-pi and electrostatic interactions, respectively. In addition to demonstrating that the active site of antibody 28B4 does indeed reflect the mechanistic information programmed in the aminophosphonic acid hapten, these high-resolution structures provide a basis for enhancing turnover rates through mutagenesis and improved hapten design

Evaluation of aerothermal modeling computer programs

Various computer programs based upon the SIMPLE or SIMPLER algorithm were studied and compared for numerical accuracy, efficiency, and grid dependency. Four two-dimensional and one three-dimensional code originally developed by a number of research groups were considered. In general, the accuracy and computational efficieny of these TEACH type programs were improved by modifying the differencing schemes and their solvers. A brief description of each program is given. Error reduction, spline flux and second upwind differencing programs are covered