Preliminary designs of an intense heavy-ion beam transport experiment to test issues for Heavy Ion Fusion (HIF) are presented. This transport channel will represent a single high current density beam at full driver scale and will evaluate practical issues such as aperture filling factors, electrons, halo, imperfect vacuum, etc., that cannot be fully tested using scaled experiments. Various machine configurations are evaluated in the context of the range of physics and technology issues that can be explored in a manner relevant to a full scale driver. it is anticipated that results from this experiment will allow confident construction of next generation ''Integrated Research Experiments'' leading to a full scale driver for energy production.

At relativistic energies, the cross section for the atomic photoelectric effect drops off as does the cross section for liberating any bound electron through Compton scattering. However, when the photon energy exceeds twice the rest mass of the electron, ionization may proceed via electron-positron pair creation. We used 1.33 MeV photons impinging on Au thin foils to study double K-shell ionization and vacuum-assisted photoionization. The preliminary results yield a ratio of vacuum-assisted photoionization and pair creation of 2x10{sup -3}, a value that is substantially higher than the ratio of photo double ionization to single photoionization that is found to be 0.5-1x10{sup -4}. Because of the difficulties and large error bars associated with the small cross sections additional measurements are needed to minimize systematic errors.

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The effective I/O bandwidth benchmark (b{_}eff{_}io) covers two goals: (1) to achieve a characteristic average number for the I/O bandwidth achievable with parallel MPI-I/O applications, and (2) to get detailed information about several access patterns and buffer lengths. The benchmark examines ''first write'', ''rewrite'' and ''read'' access, strided (individual and shared pointers) and segmented collective patterns on one file per application and non-collective access to one file per process. The number of parallel accessing processes is also varied and well-formed I/O is compared with non-well formed. On systems, meeting the rule that the total memory can be written to disk in 10 minutes, the benchmark should not need more than 15 minutes for a first pass of all patterns. The benchmark is designed analogously to the effective bandwidth benchmark for message passing (b{_}eff) that characterizes the message passing capabilities of a system in a few minutes. First results of the b{_}eff{_}io benchmark are given for IBM SP and Cray T3E systems and compared with existing benchmarks based on parallel Posix-I/O.

The ultimate limitation in obtainable resolution and sensitivity for space-based imaging systems is the size of the optical collecting aperture. Large collecting apertures are at odds with maintaining low launch costs and with current launch vehicle configurations. Development of a deployable mirror is one approach being considered to satisfy these conflicting requirements. The focus of this research is to develop fundamental technology toward the realization of deployable electron-gun-controlled piezoelectric thin films mirrors as shown below. A bimorph layer of film will bend in response to an applied electric field and can therefore be deformed into desirable shapes using a scanning electron gun. Surface curvature measurements govern the electron gun scanning strategy, yielding distributed shape corrections.

An edge-emitting buried-oxide waveguide (BOW) laser structure employing lateral selective oxidation of AlGaAs layers above and below the active region for waveguiding and current confinement is presented. This laser configuration has the potential for very small lateral optical mode size and high current confinement and is well suited for integrated optics applications where threshold current and overall efficiency are paramount. Optimization of the waveguide design, oxide layer placement, and bi-parabolic grading of the heterointerfaces on both sides of the AlGaAs oxidation layers has yielded 95% external differential quantum efficiency and 40% wall-plug efficiency from a laser that is very simple to fabricate and does not require epitaxial regrowth of any kind.

In this paper a new time-stepping method for simulating systems of rigid bodies is given. Unlike methods which take an instantaneous point of view, the method is based on impulse-momentum equations, and so does not need to explicitly resolve impulsive forces. On the other hand, the method is distinct from previous impulsive methods in that it does not require explicit collision checking and it can handle simultaneous impacts. Numerical results are given for one planar and one three-dimensional example, which demonstrate the practicality of the method, and its convergence as the step size becomes small.

The morphologies of U metal samples from deposits produced by electrorefining of Experimental Breeder Reactor-II (EBR-II) spent fuel were examined using scanning electron microscopy, energy- and wavelength-dispersive X-ray spectroscopy, and metallography. The morphologies were analyzed to find correlations with the chemistry of the samples, the ER run conditions, and the deposit performance. A rough correlation was observed between morphology and Zr concentration; samples with Zr contents greater than approximately 200 ppm showed fine-grained, polycrystalline dendritic morphologies, while samples with Zr contents less than approximately 100 ppm were comprised of agglomerations or linked chains of rhomboidal single crystals. There were few correlations found between morphology, run conditions, and deposit performance.

The major consumer electronics in U.S. homes accounted for nearly 7 percent of U.S. residential electricity consumption in 1999. We attribute more than half of this figure (3.6 percent) to televisions, videocassette recorders, and DVD players, and nearly one-third (1.8 percent) to audio products. Set-top boxes currently account for a relatively small fraction of residential electricity use (0.7 percent), but we expect this end-use to grow quickly with the proliferation of digital set-top boxes, which currently use 40 percent more energy per unit than the average TV set. In all, these consumer electronics plus telephone products consumed 75 TWh in the U.S. in 1999, half of which was consumed while the products were not in use. This energy use is expected to grow as products with new or advanced functionality hit the market.

An automated gas chromatography was used to analyze water samples contaminated with trace (parts-per-billion) concentrations of organic analytes. A custom interface introduced the liquid sample to the chromatography. This was followed by rapid chromatographic analysis. Characteristics of the analysis include response times less than one minute and automated data processing. Analytes were chosen based on their known presence in the recycle water streams of semiconductor manufacturers and their potential to reduce process yield. These include acetone, isopropanol, butyl acetate, ethyl benzene, p-xylene, methyl ethyl ketone and 2-ethoxy ethyl acetate. Detection limits below 20 ppb were demonstrated for all analytes and quantitative analysis with limited speciation was shown for multianalyte mixtures. Results are discussed with respect to the potential for on-line liquid process monitoring by this method.

The National Ignition Facility will be the largest laser system in the world. The facility, currently under construction, requires over 25,000 small optical components. The small-optics requirements and latest procurement strategy will be presented.

Quantum robots are described as mobile quantum computers and ancillary systems that move in and interact with arbitrary environments. Their dynamics is given as tasks which consist of sequences of alternating computation and action phases. A task example is considered in which a quantum robot searches a space region to find the location of a system. The possibility that the search can be more efficient than a classical search is examined by considering use of Grover's Algorithm to process the search results. This is problematic for two reasons. One is the removal of entanglements generated by the (reversible) search process. The other is that (ignoring the entanglement problem), the search process in 2 dimensional space regions is no more efficient than a classical search. However quantum searches of higher dimensional space regions are more efficient than classical searches. Reasons why quantum robots are interesting independent of these results are briefly summarized.

This paper formally introduces several stability characterizations of fixtured three-dimensional rigid bodies initially at rest and in unilateral contact with Coulomb friction. These characterizations, weak stability and strong stability, arise naturally from the dynamic model of the system, formulated as a complementarity problem. Using the tools of complementarity theory, these characterizations are studied in detail to understand their properties and to develop techniques to identify the stability classifications of general systems subjected to known external loads.

A two-dimensional (2D) photonic crystal is an attractive alternative and complimentary to its 3D counterpart, due to fabrication simplicity. A 2D crystal, however, confines light only in the 2D plane, but not in the third direction, the z-direction. Earlier experiments show that such a 2D system can exist, providing that the boundary effect in z-direction is negligible and that light is collimated in the 2D plane. Nonetheless, the usefulness of such 2D crystals is limited because they are incapable of guiding light in z-direction, which leads to diffraction loss. This drawback presents a major obstacle for realizing low-loss 2D crystal waveguides, bends and thresholdless lasers. A recent theoretical calculation, though, suggests a novel way to eliminate such a loss with a 2D photonic crystal slab. The concept of a lightcone is introduced as a criterion for fully guiding and controlling light. Although the leaky modes of a crystal slab have been studied, there have until now no experimental reports on probing its guided modes and band gaps. In this paper, a waveguide-coupled 2D photonic crystal slab is successfully fabricated from a GaAs/Al{sub x}O{sub y} material system and its intrinsic transmission properties are studied. The crystal slab is shown to have …

The support of the criticality safety community is allowing the production of benchmark descriptions of several assemblies from the ZPR Diagnostic Cores Program. The assemblies have high sensitivities to nuclear data for a few isotopes. This can highlight limitations in nuclear data for selected nuclides or in standard methods used to treat these data. The present work extends the use of the simplified model of the U9 benchmark assembly beyond the validation of k{sub eff}. Further simplifications have been made to produce a data testing benchmark in the style of the standard CSEWG benchmark specifications. Calculations for this data testing benchmark are compared to results obtained with more detailed models and methods to determine their biases. These biases or corrections factors can then be applied in the use of the less refined methods and models. Data testing results using Versions IV, V, and VI of the ENDF/B nuclear data are presented for k{sub eff}, f{sup 28}/f{sup 25}, c{sup 28}/f{sup 25}, and {beta}{sub eff}. These limited results demonstrate the importance of studying other integral parameters in addition to k{sub eff} in trying to improve nuclear data and methods and the importance of accounting for methods and/or modeling biases when using data …

Oracle WebDB is the easiest way to produce web enabled lightweight and enterprise-centric applications. This concept from Oracle has tantalized our taste for simplistic web development by using a purely web based tool that lives nowhere else but in the database. The use of online wizards, templates, and query builders, which produces PL/SQL behind the curtains, can be used straight ''out of the box'' by both novice and seasoned developers. The topic of this presentation will introduce lessons learned by developing and deploying applications built using the WebDB Component Builder in conjunction with custom PL/SQL code to empower a hybrid application. There are two kinds of WebDB components: those that display data to end users via reporting, and those that let end users update data in the database via entry forms. The presentation will also discuss various methods within the Component Builder to enhance the applications pushed to the desktop. The demonstrated example is an application entitled HOME (Helping Other's More Effectively) that was built to manage a yearly United Way Campaign effort. Our task was to build an end to end application which could manage approximately 900 non-profit agencies, an average of 4,100 individual contributions, and $1.2 million dollars. …

In the context of the LHC experiments, the physics of bottom flavoured hadrons enters in different contexts. It can be used for QCD tests, it affects the possibilities of B decays studies, and it is an important source of background for several processes of interest. The physics of b production at hadron colliders has a rather long story, dating back to its first observation in the UA1 experiment. Subsequently, b production has been studied at the Tevatron. Besides the transverse momentum spectrum of a single b, it has also become possible, in recent time, to study correlations in the production characteristics of the b and the b. At the LHC new opportunities will be offered by the high statistics and the high energy reach. One expects to be able to study the transverse momentum spectrum at higher transverse momenta, and also to exploit the large statistics to perform more accurate studies of correlations.

The development of a new class of laser systems: capable of producing intense radiation in the mid-infrared (MIR) regime (photon energies between 0.3 and 0.4 eV), opens the possibility of observing multiphoton processes in a new class of systems with lower ionization potentials than those previously studied. Of particular interest are the alkali metal atoms, which are true one-(valence)-electron systems. We present theoretical calculations of above threshold ionization (ATI) and high harmonic generation (HHG) from alkali metal atoms subject to 3-4 {micro}m laser irradiation. The ATI calculations, which use a multiple gauge propagation method, show a striking dependence in the production of high-order photoelectrons on the electron-ion potential. The HHG calculations illustrate the importance of the strong ground-to-first excited state coupling in multiphoton processes in the alkali metals.

The Demand Activated Manufacturing Architecture (DAMA) project during the last five years of work with the U.S. Integrated Textile Complex (retail, apparel, textile, and fiber sectors) has developed an inter-enterprise supply chain collaboration development methodology. The goal of this methodology is to enable a supply chain to work more efficiently and competitively. The outcomes of this methodology include: (1) A definitive description and evaluation of the role of business cultures and supporting business organizational structures in either inhibiting or fostering change to a more competitive supply chain; (2) ``As-Is'' and proposed ``To-Be'' supply chain business process models focusing on information flows and decision-making; and (3) Software tools that enable and support a transition to a more competitive supply chain, which results form a business driven rather than technologically driven approach to software design. This methodology development will continue in FY00 as DAMA engages companies in the soft goods industry in supply chain research and implementation of supply chain collaboration.

The authors have investigated the properties of GaAsSb/InGaAs type-II bilayer quantum well structures grown by molecule beam epitaxy for use in long-wavelength lasers on GaAs substrates. Structures with layer, strains and thicknesses designed to be thermodynamically stable against dislocation formation exhibit room-temperature photoluminescence at wavelengths as long as 1.43 {mu}m. The photoluminescence emission wavelength is significantly affected by growth temperature and the sequence of layer growth (InGaAs/GaAsSb vs GaAsSb/InGaAs), suggesting that Sb and/or In segregation results in non-ideal interfaces under certain growth conditions. At low injection currents, double heterostructure lasers with GaAsSb/InGaAs bilayer quantum well active regions display electroluminescence at wavelengths comparable to those obtained in photoluminescence, but at higher currents the electroluminescence shifts to shorter wavelengths. Lasers have been obtained with threshold current densities as low as 120 A/cm{sup 2} at 1.17 {mu}m, and 2.1 kA/cm{sup 2} at 1.21 {mu}m.

The authors have designed and assembled two generations of integrated micro-optical systems that deliver pump light and detect broadband laser-induced fluorescence in micro-fluidic chemical separation systems employing electrochromatography. The goal is to maintain the sensitivity attainable with larger, tabletop machines while decreasing package size and increasing throughput (by decreasing the required chemical volume). One type of micro-optical system uses vertical-cavity surface-emitting lasers (VCSELs) as the excitation source. Light from the VCSELs is relayed with four-level surface relief diffractive optical elements (DOEs) and delivered to the chemical volume through substrate-mode propagation. Indirect fluorescence from dye-quenched chemical species is collected and collimated with a high numerical aperture DOE. A filter blocks the excitation wavelength, and the resulting signal is detected as the chemical separation proceeds. Variations of this original design include changing the combination of reflective and transmissive DOEs and optimizing the high numerical aperture DOE with a rotationally symmetric iterative discrete on-axis algorithm. The authors will discuss the results of these implemented optimizations.

Alumina has been joined at 1150 degrees C and 1400 degrees C using multilayer copper/niobium/copper interlayers. Four-point bend strengths are sensitive to processing temperature, bonding pressure, and furnace environment (ambient oxygen partial pressure). Under optimum conditions, joints with reproducibly high room temperature strengths (approximately equal 240 plus/minus 20 MPa) can be produced; most failures occur within the ceramic. Joints made with sapphire show that during bonding an initially continuous copper film undergoes a morphological instability, resulting in the formation of isolated copper-rich droplets/particles at the sapphire/interlayer interface, and extensive regions of direct bonding between sapphire and niobium. For optimized alumina bonds, bend tests at 800 degrees C-1100 degrees C indicate significant strength is retained; even at the highest test temperature, ceramic failure is observed. Post-bonding anneals at 1000 degrees C in vacuum or in gettered argon were used to assess joint stability and to probe the effect of ambient oxygen partial pressure on joint characteristics. Annealing in vacuum for up to 200 h causes no significant decrease in room temperature bend strength or change in fracture path. With increasing anneal time in a lower oxygen partial pressure environment, the fracture strength decreases only slightly, but the fracture path shifts from …

Initiation and detonation properties are dramatically affected by an energetic material's microstructural properties. Sol-gel chemistry allows intimacy of mixing to be controlled and dramatically improved over existing methodologies. One material goal is to create very high power energetic materials which also have high energy densities. Using sol-gel chemistry we have made a nanostructured composite energetic material. Here a solid skeleton of fuel, based on resorcinol-formaldehyde, has nanocrystalline ammonium perchlorate, the oxidizer, trapped within its pores. At optimum stoichiometry it has approximately the energy density of HMX. Transmission electron microscopy indicated no ammonium perchlorate crystallites larger than 20 nm while near-edge soft x-ray absorption microscopy showed that nitrogen was uniformly distributed, at least on the scale of less than 80 nm. Small-angle neutron scattering studies were conducted on the material. Those results were consistent with historical ones for this class of nanostructured materials. The average skeletal primary particle size was on the order of 2.7 nm, while the nanocomposite showed the growth of small 1 nm size crystals of ammonium perchlorate with some clustering to form particles greater than 10 nm.