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Astronomical applications of adaptive optics at Lawrence Livermore National Laboratory (LLNL) has a history that extends from 1984. The program started with the Lick Observatory Adaptive Optics system and has progressed through the years to lever-larger telescopes: Keck, and now the proposed CELT (California Extremely Large Telescope) 30m telescope. LLNL AO continues to be at the forefront of AO development and science.

Herein we compare three functional families for afterglow morphologies: the homogeneous afterglow with constant shock surface energy density, the structured afterglow for which the energy density decays as a power-law as a function of viewer angle, and the gaussian afterglow which has an exponential decay of energy density with viewer angle. We simulate observed lightcurves and polarization curves for each as seen from a variety of observer vantage points. We find that the homogeneous jet is likely inconsistent with observations and suggest that the future debate on the structure of afterglow jets will be between the other two candidates.

The short pulse x-ray sources will provide a major advance in dense matter studies important to understand implosion physics for ICF as a generator of warm dense matter or a probe of finite temperature dense matter. The interaction of such a high-energy photon pulse with the initially solid matter creates highly transient states of plasmas initially whose relaxation processes are of interest to the equation of states or spectral properties of these matter. For these plasmas, assumptions such as LTE population distributions or Maxwellian electron energy distributions should be tested by employing a method that does not make these assumption a priori. Our goal is to present a model that can be used to simulate the electron distributions, the ionization balance and the spectral output of transient systems generated in the future ICF experiments. We report on the progress in developing a non-LTE atomic population kinetics code integrated with Boltzmann equation solver to provide a self-consistent time-dependent solution of the level populations and the particle energy distributions.

Thermodynamic states encountered during afterburning of explosion products gases in air were analyzed with the Cheetah code. Results are displayed in the form of Le Chatelier diagrams: the locus of states of specific internal energy versus temperature, for six different condensed explosives charges. Accuracy of the results was confirmed by comparing the fuel and products curves with the heats of detonation and combustion, and species composition as measured in bomb calorimeter experiments. Results were fit with analytic functions u = f ( T ) suitable for specifying the thermodynamic properties required for gas-dynamic models of afterburning in explosions.

These proceedings contain papers prepared for the 25th Seismic Research Review -- Nuclear Explosion Monitoring: Building the Knowledge Base, held 23-25 September, 2003 in Tucson, Arizona. These papers represent the combined research related to ground-based nuclear explosion monitoring funded by the National Nuclear Security Administration (NNSA), Defense Threat Reduction Agency (DTRA), Air Force Research Laboratory (AFRL), US Army Space and Missile Defense Command, and other invited sponsors. The scientific objectives of the research are to improve the United States capability to detect, locate, and identify nuclear explosions. The purpose of the meeting is to provide the sponsoring agencies, as well as potential users, an opportunity to review research accomplished during the preceding year and to discuss areas of investigation for the coming year. For the researchers, it provides a forum for the exchange of scientific information toward achieving program goals, and an opportunity to discuss results and future plans. Paper topics include: seismic regionalization and calibration; detection and location of sources; wave propagation from source to receiver; the nature of seismic sources, including mining practices; hydroacoustic, infrasound, and radionuclide methods; on-site inspection; and data processing.

Cloud parameterizations in large-scale models often try to predict the amount of sub-grid scale variability in cloud properties to address the significant non-linear effects of radiation and precipitation. Statistical cloud schemes provide an attractive framework to self-consistently predict the variability in radiation and microphysics but require accurate predictions of the width and asymmetry of the distribution of cloud properties. Data from the Atmospheric Radiation Measurement (ARM) program are used to assess the variability in boundary layer cloud properties for a well- mixed stratocumulus observed at the Oklahoma ARM site during the March 2000 Intensive Observing Period. Cloud boundaries, liquid water content, and liquid water path are retrieved from the millimeter wavelength cloud radar and the microwave radiometer. Balloon soundings, aircraft data, and satellite observations provide complementary views on the horizontal cloud inhomogeneity. It is shown that the width of the liquid water path probability distribution function is consistent with a model in which horizontal fluctuations in liquid water content are vertically coherent throughout the depth of the cloud. Variability in cloud base is overestimated by this model, however; perhaps because an additional assumption that the variance of total water is constant with altitude throughout the depth of the boundary layer …

Molecular dynamics (MD) simulations were carried out on the DNA oligonucleotide GGGAACAACTAG:CTAGTTGTTCCC in its native form and with guanine in the central G19:C6 base pair replaced by 8-oxoguanine (8oxoG). A box of explicit water molecules was used for solvation and Na+ counterions were added to neutralize the system. The direction and magnitude of global bending were assessed by a technique used previously to analyze simulations of DNA containing a thymine dimer. The presence of 8oxoG did not greatly affect the magnitude of DNA bending; however, bending into the major groove was significantly more probable when 8oxoG replaced G19. Crystal structures of glycosylases bound to damaged-DNA substrates consistently show a sharp bend into the major groove at the damage site. We conclude that changes in bending dynamics that assist the formation of this kink are a part of the mechanism by which glycosylases of the base excision repair pathway recognize the presence of 8oxoG in DNA.

Successful development of metallic filters with high temperature oxidation/corrosion resistance for fly ash capture is a key to enabling advanced coal combustion and power generation technologies. Compared to ceramic filters, metallic filters can offer increased resistance to impact and thermal fatigue, greatly improving filter reliability. A beneficial metallic filter structure, composed of a thin-wall (0.5mm) tube with uniform porosity (about 30%), is being developed using a unique spherical powder processing and partial sintering approach, combined with porous sheet rolling and resistance welding. Alloy choices based on modified superalloys, e.g., Ni-16Cr-4.5Al-3Fe (wt.%), are being tested in porous and bulk samples for oxide (typically alumina) scale stability in simulated oxidizing/sulfidizing atmospheres found in PFBC and IGCC systems at temperatures up to 850 C. Recent ''hanging o-ring'' exposure tests in actual combustion systems at a collaborating DOE site (EERC) have been initiated to study the combined corrosive effects from particulate deposits and hot exhaust gases. New studies are exploring the correlation between sintered microstructure, tensile strength, and permeability of porous sheet samples.

This paper presents information and data relative to recent advances in the development at Oak Ridge National Laboratory of porous inorganic membranes for high-temperature hydrogen separation. The Inorganic Membrane Technology Laboratory, which was formerly an organizational element of Bechtel Jacobs Company, LLC, was formally transferred to Oak Ridge National Laboratory on August 1, 2002, as a result of agreements reached between Bechtel Jacobs Company, the management and integration contractor at the East Tennessee Technology Park (formerly the Oak Ridge Gaseous Diffusion Plant or Oak Ridge K-25 Site); UT-Battelle, the management and operating contractor of Oak Ridge National Laboratory; and the U.S. Department of Energy (DOE) Oak Ridge Operations Office. Research emphasis during the last year has been directed toward the development of high-permeance (high-flux) and high-separation-factor metal-supported membranes. Performance data for these membranes are presented and are compared with performance data for membranes previously produced under this program and for membranes produced by other researchers. New insights into diffusion mechanisms are included in the discussion. Fifteen products, many of which are the results of research sponsored by the DOE Fossil Energy Advanced Research Materials Program, have been declared unclassified and have been approved for commercial production.

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In this paper, we report on the halo formation and emittance growth driven by a parametric resonance during mismatched beam-beam collisions. In the regime of the weak-strong beam-beam interaction, if two beams have the same machine tunes, on-axis head-on collisions between a mismatched strong beam and a weak beam will not cause the formation of halo. However, if the two beams collide with an initial offset, the beam-beam force from the mismatched strong beam can cause halo formation and emittance growth in the weak beam. Meanwhile, if two beams have different machine tunes, for opposite charged colliding beams, when the machine tune of the weak beam is smaller than that of strong beam, there is emittance growth in the weak beam. When the machine tune of the weak beam is larger than that of the strong beam, there is little emittance growth. In the regime of strong-strong beam-beam interaction, halo is formed in both beams even when the two beams collide head-on on the axis with equal machine tunes. This puts a strong requirement for a good beam match during the injection to colliders in order to avoid the emittance growth.

Using ion implantation followed by pulsed-laser melting (PLM), we have synthesized ferromagnetic films of Ga{sub 1-x}Mn{sub x}As. Ion-channeling experiments reveal that these films are single crystalline and have high Mn substitutionality while variable temperature resistivity measurements reveal the strong Mn-hole interactions characteristic of carrier-mediated ferromagnetism in homogeneous DMS's. We have observed Curie temperatures (T{sub C}'s) of approximately 80 K for films with substitutional Mn concentrations of x=0.04. The use of n-type counter doping as a means of increasing Mn substitutionality and T{sub c} is explored by co-implantation of Mn and Te into GaAs. In Ga{sub 1-x}Mn{sub x}P samples synthesized using our technique, the implanted layer regrows as an epitaxial single crystal capped by a highly defective surface layer. These samples display ferromagnetism with T{sub c} {approx} 23 K.

During the past 30 years superconducting magnet systems have enabled accelerators to achieve energies and luminosities that would have been impractical if not impossible with resistive magnets. By far, NbTi has been the preferred conductor for this application because of its ductility and insensitivity of Jc to mechanical strain. This is despite the fact that Nb{sub 3}Sn has a more favorable Jc vs. B dependence and can operate at much higher temperatures. Unfortunately, NbTi conductor is reaching the limit of it usefulness for high field applications. Despite incremental increases in Jc and operation at superfluid temperatures, magnets are limited to approximately a 10 T field. Improvements in conductor performance combined with future requirements for accelerator magnets to have bore fields greater than 10 T or operate in areas of large beam-induced heat loads now make Nb{sub 3}Sn look attractive. Thus, laboratories in several countries are actively engaged in programs to develop Nb{sub 3}Sn accelerator magnets for future accelerator applications. A summary of this important research activity is presented along with a brief history of Nb{sub 3}Sn accelerator magnet development and a discussion of requirements for future accelerator magnets.

Polycrystalline SiC samples hot-pressed with aluminum, boron, and carbon sintering additions (ABC-SiC) were characterized using transmission electron microscopy. The study focused on the effects of high temperature treatment on microstructure.

Remediation of eight waste pits at the Department of Energy (DOE) Fernald site, located northwest of Cincinnati, Ohio, involves excavating approximately one million tonnes in-situ of low-level waste which were placed in pits during Fernald's production era. This unique project, one of the largest in the history of CERCLA/Superfund, includes uranium and thorium contaminated waste, soils and sludges. These wet soils and sludges are thermally dried in a processing facility to meet Department of Transportation (DOT) transportation and disposal facility waste acceptance criteria, loaded into railcars and shipped to the Envirocare waste disposal facility at Clive, Utah. This project is now approximately 60% complete with more than 415,000 tonnes (460,000 tons) of waste material safely shipped in 74 unit trains to Envirocare. Work is scheduled to be completed in early 2005. Success to date demonstrates that a major DOE site remediation project can be safely and successfully executed in partnership with private industry, utilizing proven commercial best practices, existing site labor resources and support of local stakeholders. In 1997 under the DOE's privatization initiative, Fluor Fernald, Inc. (Fluor Fernald) solicited the services of the remediation industry to design, engineer, procure, construct, own and operate a facility that would undertake the …

Two, 111 GBq (3 Curie) radium-beryllium (RaBe) sources were in underground storage at the Brookhaven National Laboratory (BNL) since 1988. These sources originated from Princeton Plasma Physics Laboratory (PPPL) where they were used to calibrate neutron detection diagnostics. In 1999, PPPL and BNL began a collaborative effort to expand the use of an innovative pilot-scale technology and bring it to full-scale deployment to shield these sources for eventual transport and burial at the Hanford Burial site. The transport/disposal container was constructed of depleted uranium oxide encapsulated in polyethylene to provide suitable shielding for both gamma and neutron radiation. This new material can be produced from recycled waste products (DU and polyethylene), is inexpensive, and can be disposed with the waste, unlike conventional lead containers, thus reducing exposure time for workers. This paper will provide calculations and information that led to the initial design of the shielding. We will also describe the production-scale processing of the container, cost, schedule, logistics, and many unforeseen challenges that eventually resulted in the successful fabrication and deployment of this shield. We will conclude with a description of the final configuration of the shielding container and shipping package along with recommendations for future shielding designs.

Computational fluid-dynamics numerical models are developed for joule-heated slurry fed waste glass melters, such as the Defense Waste Processing Facility Melter. An important feature of the analyses is the simulation of the cold cap region with its thermally resistant foamy layer. Using a simplified model which describes the foam void fraction as a function of temperature, based on laboratory sample testing, characteristic features of the cold cap are simulated. Two- and three-dimensional models are presented.

The physics potential of low-performance and high-performance neutrino factories is briefly reviewed.

Over the past decade, liquefaction assessments have been performed for many existing and planned critical facilities at the Department of Energy's Savannah River Site (SRS). The assessments incorporated site-specific Cyclic Resistance Ratio (CRR) and K with the use of the cone penetration test (CPT). The SRS-specific CRR and K were developed from laboratory testing of carefully collected samples. Test results show SRS soils have increased liquefaction resistance of two to three times when compared to standard literature for Holocene-age deposits. This increase in strength can be attributed to many factors such as aging and overconsolidation. The purpose of this paper is to discuss liquefaction methodologies used at the SRS. Specifically, (1) use of the CPT and correlations of CPT-derived results with that of high-quality undisturbed samples; (2) aging; and (3) K vertical confining stress factor.

Caching techniques have been used to improve the performance gap of storage hierarchies in computing systems. In data intensive applications that access large data files over wide area network environment, such as a data grid,caching mechanism can significantly improve the data access performance under appropriate workloads. In a data grid, it is envisioned that local disk storage resources retain or cache the data files being used by local application. Under a workload of shared access and high locality of reference, the performance of the caching techniques depends heavily on the replacement policies being used. A replacement policy effectively determines which set of objects must be evicted when space is needed. Unlike cache replacement policies in virtual memory paging or database buffering, developing an optimal replacement policy for data grids is complicated by the fact that the file objects being cached have varying sizes and varying transfer and processing costs that vary with time. We present an accurate model for evaluating various replacement policies and propose a new replacement algorithm referred to as ''Least Cost Beneficial based on K backward references (LCB-K).'' Using this modeling technique, we compare LCB-K with various replacement policies such as Least Frequently Used (LFU), Least Recently …

A theoretical study is reported of the transition between the ground state ({sup 1}A{sub g}) and the lowest triplet state (1{sup 3}B{sub 1u}) of ethylene based on the diffusion Monte Carlo (DMC) variant of the quantum Monte Carlo method. Using DMC trial functions constructed from Hartree-Fock, complete active space self-consistent field and multi-configuration self-consistent field wave functions, we have computed the atomization energy and the heat of formation of both states, and adiabatic and vertical energy differences between these states using both all-electron and effective core potential DMC. The ground state atomization energy and heat of formation are found to agree with experiment to within the error bounds of the computation and experiment. Predictions by DMC of the triplet state atomization energy and heat of formation are presented. The adiabatic singlet-triplet energy difference is found to differ by 5 kcal/mol from the value obtained in a recent photodissociation experiment.

The Fermilab Tevatron has the unique opportunity to explore physics at the electroweak scale with the highest ever proton-antiproton collision energy of {radical}s = 1.96 TeV and unprecedented luminosity. About 20 times more data is expected to be collected during the first phase of the collider Run II which is in its second year of data-taking. The second phase of Run II, expected to begin in 2005, will increase the integrated luminosity to about 10-15 fb{sup -1}. Discovering a low mass Higgs boson and evidence for Supersymmetry or for other new physics beyond the Standard Model are the main physics goals for Run II. It is widely recognized that the use of advanced analysis methods will be crucial to achieve these goals. I discuss the current status of Run II at the Tevatron, prospects and foreseen applications of advanced analysis methods.

As of October 2001, approximately 7,000 yd{sup 3} of stockpiled soil, contaminated to varying degrees with radioactive materials and heavy metals, remained at Brookhaven National Laboratory (BNL) after the remediation of the BNL Chemical/Animal/Glass Pits disposal area. During the 1997 removal action, the more hazardous/radioactive materials were segregated, along with, chemical liquids and solids, animal carcasses, intact gas cylinders, and a large quantity of metal and glass debris. Nearly all of these materials have been disposed of. In order to ensure that all debris was removed and to characterize the large quantity of heterogeneous soil, BNL initiated an extended sorting, segregation, and characterization project, co-funded by the BNL Environmental Management Directorate and the DOE EM Office of Science and Technology Accelerated Site Technology Deployment (ASTD) program. Project objectives were to remove any non-conforming items, and to assure that mercury and radioactive contaminant levels were within acceptable limits for disposal as low-level radioactive waste. Sorting and segregation were conducted simultaneously. Large stockpiles, ranging from 150 to 1,200 yd{sup 3}, were subdivided into manageable 20 yd{sup 3} ''subpiles'' after powered vibratory screening. The 1/2 inch screen removed gravel and almost all non-conforming items, which were separated for further characterization. Soil that passed …