I present preliminary results of the measurement of the hadronic mass spectrum and its first three spectral moments in inclusive charmless semileptonic B-meson decays. The truncated hadronic mass moments are used for the first determination of the b-quark mass and the nonperturbative parameters {mu}{sub {pi}}{sup 2} and {rho}{sub D}{sup 3} in this B-meson decay channel. The study is based on 383 x 10{sup 6} B{bar B} decays collected with the BABAR experiment at the PEP-II e{sup +}e{sup -} storage rings, located at the Stanford Linear Accelerator Center. The first, second central, and third central hadronic mass moment with a cut on the hadronic mass m{sub X}{sup 2} < 6.4GeV{sup 2} and the lepton momentum p* > 1 GeV are measured to be: M{sub 1} = (1.96 {+-} 0.34{sub stat} {+-} 0.53{sub syst}) GeV{sup 2}; U{sub 2} = (1.92 {+-} 0.59{sub stat} {+-} 0.87{sub syst}) GeV{sup 4}; and U{sub 3} = (1.79 {+-} 0.62{sub stat} {+-} 0.78{sub syst}) GeV{sup 6}; with correlation coefficients {rho}{sub 12} = 0.99, {rho}{sub 23} = 0.94, and {rho}{sub 13} = 0.88, respectively. Using Heavy Quark Effective Theory-based predictions in the kinetic scheme we extract: m{sub b} = (4.60 {+-} 0.13{sub stat} {+-} 0.19{sub syst} {+-} 0.10{sub …

We have carried out a search for a charmed baryon {Omega}{sup *}{sub c} decaying to {Omega}{sup 0}{sub c} and a {gamma} where {Omega}{sub c} candidates are reconstructed using decay modes {Omega}{sup -}{pi}{sup +}(c1), {Omega}{sup -}{pi}{sup +}{pi}{sup 0}(c2), {Omega}{sup -}{pi}{sup +}{pi}{sup -}{pi}{sup +}(c3) and {Xi}{sup -}K{sup -}{pi}{sup +}{pi}{sup +}(c4). This search is performed by analyzing integrated luminosity of 230.7 fb{sup -1} data collected by the BABAR detector at the Stanford Linear Accelerator Center. In decay channel {Omega}{sup *}{sub c} {yields} {Omega}{sup 0}{sub c}({Omega}{sup -}{pi}{sup +}){gamma} (C1), we observe a signal yield of 39.2{sup +9.8}{sub -9.1}(stat){+-}6.0(syst) events with a significance of 4.2 standard deviations. In decay channels {Omega}{sup *}{sub c} {yields} {Omega}{sup 0}{sub c}({Omega}{sup -}{pi}{sup +}{pi}{sup 0}){gamma} (C2) and {Omega}{sup *}{sub c} {yields} {Omega}{sup 0}{sub c}({Xi}{sup -}K{sup -}{pi}{sup +}{pi}{sup +}){gamma} (C4), we observe signal yields of 55.2{sup 16.1}{sub -15.2} {+-} 5.6 and 20.2{sup +9.3}{sub -8.5} {+-} 3.1 with significances of 3.4 and 2.0 {sigma}, respectively. As for the {Omega}{sup *}{sub c} {yields} {Omega}{sup 0}{sub c}({Omega}{sup -}{pi}{sup +}{pi}{sup -}{pi}{sup +}){gamma} (C3) decay channel, we observe signal yields of -5.1{sup +5.3.8}{sub -4.7}{+-}1.0 without a positive significance. We assume the same production mechanism for the four decay channels of {Omega}{sup *}{sub c} studied. By combining …

The goal of this work is to characterize surfaces of intermetallics, including quasicrystals. In this work, surface characterization is primarily focused on composition and structure using X-ray photoelectron spectroscopy (XPS) and scanning tunneling microscopy (STM) performed under ultrahigh vacuum (UHV) conditions.

The synthesis of magnetic nanoparticles has long been an area of active research. Magnetic nanoparticles can be used in a wide variety of applications such as magnetic inks, magnetic memory devices, drug delivery, magnetic resonance imaging (MRI) contrast agents, and pathogen detection in foods. In applications such as MRI, particle uniformity is particularly crucial, as is the magnetic response of the particles. Uniform magnetic particles with good magnetic properties are therefore required. One particularly effective technique for synthesizing nanoparticles involves biomineralization, which is a naturally occurring process that can produce highly complex nanostructures. Also, the technique involves mild conditions (ambient temperature and close to neutral pH) that make this approach suitable for a wide variety of materials. The term 'bioinspired' is important because biomineralization research is inspired by the naturally occurring process, which occurs in certain microorganisms called 'magnetotactic bacteria'. Magnetotactic bacteria use biomineralization proteins to produce magnetite crystals having very good uniformity in size and morphology. The bacteria use these magnetic particles to navigate according to external magnetic fields. Because these bacteria synthesize high quality crystals, research has focused on imitating aspects of this biomineralization in vitro. In particular, a biomineralization iron-binding protein found in a certain species of …

This dissertation focused on new applications of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The diverse fields that were investigated show the versatility of the technique. In Chapter 2, LA-ICP-MS was used to investigate the rare earth element (REE) profiles of garnets from the Broken Hill Deposit in New South Wales, Australia. The normalized REE profiles helped to shed new light on the formation of deposits of sulfide ores. This information may be helpful in identifying the location of sulfide ore deposits in other locations. New sources of metals such as Pg, Zn, and Ag, produced from these ores, are needed to sustain our current technological society. The application of LA-ICP-MS presented in Chapter 3 is the forensics analysis of automotive putty and caulking. The elemental analysis of these materials was combined with the use of Principal Components Analysis (PCA). The PCA comparison was able to differentiate the automotive putty samples by manufacturer and lot number. The analysis of caulk was able to show a differentiation based on manufacturer, but no clear differentiation was shown by lot number. This differentiation may allow matching of evidence in the future. This will require many more analyses and the construction of a …

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The unique combination of magnetic properties and structural transitions exhibited by many members of the R{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4} family (R = rare earths, 0 ≤ x ≤ 1) presents numerous opportunities for these materials in advanced energy transformation applications. Past research has proven that the crystal structure and magnetic ordering of the R{sub 5(Si{sub x}Ge{sub 1-x}){sub 4} compounds can be altered by temperature, magnetic field, pressure and the Si/Ge ratio. Results of this thesis study on the crystal structure of the Er{sub 5}Si{sub 4} compound have for the first time shown that the application of mechanical forces (i.e. shear stress introduced during the mechanical grinding) can also result in a structural transition from Gd{sub 5}Si{sub 4}-type orthorhombic to Gd{sub 5}Si{sub 2}Ge{sub 2}-type monoclinic. This structural transition is reversible, moving in the opposite direction when the material is subjected to low-temperature annealing at 500 ˚C. Successful future utilization of the R{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4} family in novel devices depends on a fundamental understanding of the structure-property interplay on the nanoscale level, which makes a complete understanding of the microstructure of this family especially important. Past scanning electron microscopy (SEM) observation has shown that nanometer-thin plates exist in every …

The Standard Model (SM) is one of the most tested and verified physical theories of all time, present experimental observations are consistent with SM expectations. On the other hand SM can not explain many physical observations: the cosmological observations possibly infer the presence of dark matter which is clearly beyond the SM expectations; the SM Higgs model, while explaining the generation of fermion masses, can not explain the hierarchy problem and a non natural fine tuning of SM is needed to cancel out quadratic divergences in the Higgs boson mass. New physics (NP) beyond SM should hence be investigated: rising the energy above NP processes thresholds, and detecting new particles or new effects not predicted by the standard model directly, is one of the possible approaches; another approach is to make precision measurements of well known processes or looking for rare processes which involve higher order contribution from NP processes, this approach need higher luminosities with respect to the previous approach but lower beam energies. Search for Lepton Flavor Violation (LFV) in charged lepton decays is promising: neutrino physics provides indeed a clear and unambiguous evidence of LFV in the neutral lepton sector via mixing processes, which have been observed …

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The technological age has in large part been driven by the applications of semiconductors, and most notably by silicon. Our lives have been thoroughly changed by devices using the broad range of semiconductor technology developed over the past forty years. Much of the technological development has its foundation in research carried out on the different semiconductors whose properties can be exploited to make transistors, lasers, and many other devices. While the technological focus has largely been on silicon, many other semiconductor systems have applications in industry and offer formidable academic challenges. Diffusion studies belong to the most basic studies in semiconductors, important from both an application as well as research standpoint. Diffusion processes govern the junctions formed for device applications. As the device dimensions are decreased and the dopant concentrations increased, keeping pace with Moore's Law, a deeper understanding of diffusion is necessary to establish and maintain the sharp dopant profiles engineered for optimal device performance. From an academic viewpoint, diffusion in semiconductors allows for the study of point defects. Very few techniques exist which allow for the extraction of as much information of their properties. This study focuses on diffusion in the semiconductor gallium antimonide (GaSb). As will become …

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Designing an adaptive optics (AO) system for extremely large telescopes (ELT's) will present new optical engineering challenges. Several of these challenges are addressed in this work, including first-order design of multi-conjugate adaptive optics (MCAO) systems, pyramid wavefront sensors (PWFS's), and laser guide star (LGS) spot elongation. MCAO systems need to be designed in consideration of various constraints, including deformable mirror size and correction height. The y,{bar y} method of first-order optical design is a graphical technique that uses a plot with marginal and chief ray heights as coordinates; the optical system is represented as a segmented line. This method is shown to be a powerful tool in designing MCAO systems. From these analyses, important conclusions about configurations are derived. PWFS's, which offer an alternative to Shack-Hartmann (SH) wavefront sensors (WFS's), are envisioned as the workhorse of layer-oriented adaptive optics. Current approaches use a 4-faceted glass pyramid to create a WFS analogous to a quad-cell SH WFS. PWFS's and SH WFS's are compared and some newly-considered similarities and PWFS advantages are presented. Techniques to extend PWFS's are offered: First, PWFS's can be extended to more pixels in the image by tiling pyramids contiguously. Second, pyramids, which are difficult to manufacture, can …

When the field of modern publishing was on a collision course with telecommunications, publishing organizations had to come up to speed in fields that were, heretofore, completely foreign and technologically forbidding to them. For generations, the technology of publishing centered on offset lithography, typesetting, and photography--fields that saw evolutionary and incremental change from the time of Guttenberg. But publishing now includes making information available over the World Wide Web--Internet publishing--with its ever-accelerating rate of technological change and dependence on computers and networks. Clearly, we need a methodology to help anyone in the field of Internet publishing plan for the future, and there is a well-known, well-tested technique for just this purpose--Scenario Planning. Scenario Planning is an excellent tool to help organizations make better decisions in the present based on what they identify as possible and plausible scenarios of the future. Never was decision making more difficult or more crucial than during the years of this study, 1996-1999. This thesis takes the position that, by applying Scenario Planning, the Technical Information Department at LLNL, a large government laboratory (and organizations similar to it), could be confident that moving into the telecommunications business of Internet publishing stood a very good chance of …

The majority of this research has been in developing a model to describe the magnetostrictive properties of Terfenol-D, Tb{sub 1{minus}x}Dy{sub x}Fe{sub y} (x = 0.7-0.75 and y = 1.8--2.0), a rare earth-iron alloy which displays much promise for use in device applications. In the first chapter an introduction is given to the phenomena of magnetization and magnetostriction. The magnetic processes responsible for the observed magnetic properties of materials are explained. An overview is presented of the magnetic properties of rare earths, and more specifically the magnetic properties of Terfenol-D. In the second chapter, experimental results are presented on three composition of Tb{sub 1{minus}x}Dy{sub x}Fe{sub y} with x = 0.7, y= 1.9, 1.95, and x= 0.73, y= 1.95. The data were taken for various levels of prestress to show the effects of composition and microstructure on the magnetic and magnetostrictive properties of Terfenol-D. In the third chapter, a theoretical model is developed based on the rotation of magnetic domains. The model is used to explain the magnetic and magnetostrictive properties of Terfenol-D, including the observed negative strictions and large change in strain. The fourth chapter goes on to examine the magnetic properties of Terfenol-D along different crystallographic orientations. In the fifth …

Optical parametric amplification is an established broadband amplification technology based on a second-order nonlinear process of difference-frequency generation (DFG). When used in chirped pulse amplification (CPA), the technology has been termed optical parametric chirped pulse amplification (OPCPA). OPCPA holds a potential for producing unprecedented levels of peak and average power in optical pulses through its scalable ultrashort pulse amplification capability and the absence of quantum defect, respectively. The theory of three-wave parametric interactions is presented, followed by a description of the numerical model developed for nanosecond pulses. Spectral, temperature and angular characteristics of OPCPA are calculated, with an estimate of pulse contrast. An OPCPA system centered at 1054 nm, based on a commercial tabletop Q-switched pump laser, was developed as the front end for a large Nd-glass petawatt-class short-pulse laser. The system does not utilize electro-optic modulators or multi-pass amplification. The obtained overall 6% efficiency is the highest to date in OPCPA that uses a tabletop commercial pump laser. The first compression of pulses amplified in highly nondegenerate OPCPA is reported, with the obtained pulse width of 60 fs. This represents the shortest pulse to date produced in OPCPA. Optical parametric amplification in {beta}-barium borate was combined with laser amplification …

A note from January 26, 1981 on the name change from the DGPC to the Dallas Gay Alliance.

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Pond 207C at Rocky Flats Environmental Technology Site (RFETS) contains process wastewaters characterized by high levels of nitrates and other salts, heavy metal contamination, and low level alpha activity. The purpose of this research was to investigate the feasibility of treating a high-nitrate waste, contaminated with heavy metals, with a coupled dewateriug and S/S process, as well as to investigate the effects of biodenitrification pretreatment on the S/S process. Pond 207C residuals served as the target waste. A bench-scale treatability study was conducted to demonstrate an S/S process that would minimize final product volume without a significant decrease in contaminant stabilization or loss of desirable physical characteristics. The process formulation recommended as a result a previous S/S treatability study conducted on Pond 207C residuals was used as the baseline formulation for this research. Because the actual waste was unavailable due to difficulties associated with radioactive waste handling and storage, a surrogate waste, of known composition and representative of Pond 207C residuals, was used throughout this research. The contaminants of regulatory concern added to the surrogate were cadmium, chromium, nickel, and silver. Product volume reduction was achieved by dewatering the waste prior to S/S treatment. The surrogate was dewatered by evaporation …