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Texas Stonewall Democratic Caucus Custom Report

Description: Custom report with a net income of $355.00 for the period ending on March 16, 2001. There is a balance sheet of total liabilities and equity of $355.00. Included is a general ledger of all the financial transactions as of March 16, 2001. Also, there is an Officers and Board of Directors phone list.
Date: March 16, 2001
Partner: UNT Libraries Special Collections
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Deposit Summary

Description: Deposit summary of $10.00 made on March 21, 2001
Date: March 21, 2001
Partner: UNT Libraries Special Collections
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Carbon fiber plates production for the CMS tracker outer barrel detector

Description: The production methods together with the achieved flatness and thickness of the composite support structures of the CMS tracker outer barrel (TOB) detector are presented. Possible areas of improvement in the process and in the materials used are also suggested.
Date: March 1, 2001
Creator: Lanfranco, Giobatta
Partner: UNT Libraries Government Documents Department
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Seismic Characterization of Coal-Mining Seismicity in Utah for CTBT Monitoring

Description: Underground coal mining (down to {approx}0.75 km depth) in the contiguous Wasatch Plateau (WP) and Book Cliffs (BC) mining districts of east-central Utah induces abundant seismicity that is monitored by the University of Utah regional seismic network. This report presents the results of a systematic characterization of mining seismicity (magnitude {le} 4.2) in the WP-BC region from January 1978 to June 2000-together with an evaluation of three seismic events (magnitude {le} 4.3) associated with underground trona mining in southwestern Wyoming during January-August 2000. (Unless specified otherwise, magnitude implies Richter local magnitude, M{sub L}.) The University of Utah Seismograph Stations (UUSS) undertook this cooperative project to assist the University of California Lawrence Livermore National Laboratory (LLNL) in research and development relating to monitoring the Comprehensive Test Ban Treaty (CTBT). The project, which formally began February 28, 1998, and ended September 1, 2000, had three basic objectives: (1) Strategically install a three-component broadband digital seismic station in the WP-BC region to ensure the continuous recording of high-quality waveform data to meet the long-term needs of LLNL, UUSS, and other interested parties, including the international CTBT community. (2) Determine source mechanisms--to the extent that available source data and resources allowed--for comparative seismic characterization of stress release in mines versus earthquakes in the WP-BC study region. (3) Gather and report to LLNL local information on mine operations and associated seismicity, including ''ground truth'' for significant events. Following guidance from LLNL's Technical Representative, the focus of Objective 2 was changed slightly to place emphasis on three mining-related events that occurred in and near the study area after the original work plan had been made, thus posing new targets of opportunity. These included: a magnitude 3.8 shock that occurred close to the Willow Creek coal mine in the Book Cliffs area on February 5, 1998 (UTC …
Date: March 1, 2001
Creator: Arabasz, W J & Pechmann, J C
Partner: UNT Libraries Government Documents Department
open access

Configuration Manual Polarized Proton Collider at RHIC

Description: In this report, the authors present their design to accelerate and store polarized protons in RHIC, with the level of polarization, luminosity, and control of systematic errors required by the approved RHIC spin physics program. They provide an overview of the physics to be studied using RHIC with polarized proton beams, and a brief description of the accelerator systems required for the project.
Date: March 1, 2001
Creator: Roser, T.; MacKay, W. W.; Alekseev, I.; Bai, M.; Brown, K.; Bunce, G. et al.
Partner: UNT Libraries Government Documents Department
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Chirped-Pulse Inverse Free Electron Laser: A Tabletop, High-Gradient Vacuum Laser Accelerator

Description: The inverse free-electron laser (IFEL) interaction is studied both theoretically and numerically in the case where the drive laser intensity approaches the relativistic regime, and the pulse duration is only a few optical cycles long. We show that by using an ultrashort, ultrahigh-intensity drive laser pulse, the IFEL interaction bandwidth and accelerating gradient are increased considerably, thus yielding large energy gains. Using a chirped pulse and negative dispersion focusing optics allows one to take further advantage of the laser optical bandwidth and produce a chromatic line focus maximizing the gradient. The combination of these novel ideas results in a compact vacuum laser accelerator capable of accelerating picosecond electron bunches with a high gradient (GeV/m) and very low energy spread. A computer code which takes into account the three-dimensional nature of the interaction is currently in development and results are expected this Spring.
Date: March 5, 2001
Creator: Hartemann, F. V.; Troha, A. L. & Baldis, H. A.
Partner: UNT Libraries Government Documents Department
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U.S. Energy Flow - 1999

Description: Lawrence Livermore National Laboratory (LLNL) has prepared similar flow charts of U.S. energy consumption since 1972. The chart follows the flow of individual fuels and compares these on the basis of a common energy unit of quadrillion British thermal units (Btu). A quadrillion, or ''quad,'' is 10{sup 15}. One Btu is the quantity of heat needed to raise the temperature of 1 pound of water by 1 F at or near 39.2 F. The width of each colored line across this chart is in proportion to the amount of quads conveyed. (Exception: lines showing extremely small amounts have been made wide enough to be clearly visible.) In most cases, the numbers used in this chart have been rounded to the nearest tenth of a quad, although the original data was published in hundredths or thousandths of a quad. As a consequence of independent rounding, some of the summary numbers may not appear to be a precise total of their various components. The first chart in this document uses quadrillion Btu's to conform with data from the U.S. Department of Energy's Energy Information Administration (EIA). However, the second chart is expressed in exajoules. A joule is the metric unit for heat. One Btu equals 1,055.06 joules; and one quadrillion Btu's equals 1.055 exajoules (an exajoule is 10{sup 18} joules).
Date: March 1, 2001
Creator: Kaiper, G V
Partner: UNT Libraries Government Documents Department
open access

Laboratory Studies of the Effects of Pressure and Dissolved Gas Supersaturation on Turbine-Passed Fish

Description: The objective of this study was to examine the relative importance of pressure changes as a source of turbine-passage injury and mortality. Specific tests were designed to quantify the response of fish to rapid pressure changes typical of turbine passage, with and without the complication of the fish being acclimated to gas supersaturated water. We investigated the responses of rainbow trout (Oncorhynchus mykiss), chinook salmon (O. tshawytscha), and bluegill sunfish (Lepomis macrochirus) to these two stresses, both singly and in combination.
Date: March 23, 2001
Creator: Abernethy, Cary S.; Amidan, Brett G. & Cada, G F.
Partner: UNT Libraries Government Documents Department
open access

Mapping of Enhanced Nuclear Stability in the Heaviest Elements

Description: Predictions of the properties of nuclides near the extreme limits of nuclear stability provide a measure of our understanding of the fundamental properties of matter and the fission process. Predictions of an ''island of stability'' of long-lived superheavy elements beyond the limits of the known nuclides date back more than 30 years; during this time, there have been many unsuccessful searches for these nuclei. During the last decade, there has been a large effort by our group and others to systematically discover and characterize the properties of the intervening unstable nuclei. Starting 10 years ago, in an on-going collaboration with Russian scientists at the Joint Institute for Nuclear Research (JINR) at Dubna, Russia, we observed the decays of previously unknown isotopes of elements 106, 108, and 110 whose properties are determined by subtleties in the nuclear structure caused by the shell effects that are predicted to result in the island of stability in the still-heavier elements. The resulting data have been successfully reproduced by the theoreticians, whose refined predictions of the decay modes and production rates of the superheavy elements have enabled us to design experiments with the sensitivity to locate these elusive nuclides.
Date: March 6, 2001
Creator: Moody, K J; Wild, J F; Stoyer, N J; Stoyer, M A; Laue, C A & Lougheed, R W
Partner: UNT Libraries Government Documents Department
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Development of a Multi-Layer Guided Wave Inspection Technique

Description: This study investigates the inspection of a particular layer of a multi-layer structure using ultrasonic guided waves. Techniques based on Lamb waves have been developed for the inspection of plate structures and are well understood. Guided waves also exist in multi-layered plates as well. Energy distributions vary across the thickness of a multi-layer structure depending on the mode and frequency. Hence, a potential way to inspect the bottom layer of a structure is to find modes with sufficient energy in the bottom layer.
Date: March 12, 2001
Creator: Quarry, M; Chinn, D & Hay, T
Partner: UNT Libraries Government Documents Department
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Distortion Correction for the Many Beam Fabry Perot Velocimeter

Description: Graphical curves and text tables are presented that map out time and space distortions for data obtained from film records of the Many Beam Fabry Perot Velocimeter. Effective distortion corrections extracted from these mappings can be applied to upcoming velocimetry experiments, but only with limited success over periods of a year or more into the future. A method of using three fiducials to provide fresh time and space distortion data on each film record is presented as a more reliable procedure to correct distortions to an acceptable level of accuracy.
Date: March 21, 2001
Creator: Avara, G.; Collins, L. & Rivera, A.
Partner: UNT Libraries Government Documents Department
open access

Science Day Abstracts

Description: No Description Available.
Date: March 12, 2001
Creator: Kline, K
Partner: UNT Libraries Government Documents Department
open access

Isotopic Tracers for Delineating Non-Point Source Pollutants in Surface Water

Description: This study tested whether isotope measurements of surface water and dissolved constituents in surface water could be used as tracers of non-point source pollution. Oxygen-18 was used as a water tracer, while carbon-14, carbon-13, and deuterium were tested as tracers of DOC. Carbon-14 and carbon-13 were also used as tracers of dissolved inorganic carbon, and chlorine-36 and uranium isotopes were tested as tracers of other dissolved salts. In addition, large databases of water quality measurements were assembled for the Missouri River at St. Louis and the Sacramento-San Joaquin Delta in California to enhance interpretive results of the isotope measurements. Much of the water quality data has been under-interpreted and provides a valuable resource to investigative research, for which this report exploits and integrates with the isotope measurements.
Date: March 1, 2001
Creator: Davisson, M L
Partner: UNT Libraries Government Documents Department
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Progress in Modeling Pu Properties and Aging - ESC Review, March 19-23, 2001

Description: An important component of the Pu aging programs both here at LLNL and at LANL is the development of models for the aging processes. These models will, in the foreseeable future, be validated with more and more data from different experiments, and eventually enable us to predict the lifetime of pits. The processes of aging from within the material are mainly caused by the radioactive decay of Pu, and this produces three drivers for changes in properties: (1) Radiation damage in the form of displacements, of defects, of dislocations, and voids. (2) Helium will aggregate in the form of bubbles and cavities. (3) Uranium, Americium, and Neptunium will change the chemical composition and perhaps the phase stability. All the three drivers act synergistically, no doubt. But it is useful to approach the complexity of Pu aging with the strategy of ''first divide, conquer, and then unify''. In this spirit, we have divided the program into three major task areas with individual subtasks to be conquered by various researchers. The subtasks and staffing has changed somewhat from last year, and this is indicated on the viewgraph by underlines. Undoubtedly, it will change in the future, but the objectives of the major tasks and of the entire project will not change until the mission as stated at the beginning will have been accomplished. As you see from the third task, there is a strong emphasis on providing theoretical and computational support for critical, fundamental experiments. Before reviewing the progress made last year for the various tasks, let me briefly state what the physical properties are that we monitor for signs of aging. Prominent is the change in density and microstructure, and its effects on strength and EOS. You will hear little if anything at all about the latter two properties, but work …
Date: March 29, 2001
Creator: Wolfer, W G; Caturla, M; Kubota, A; Quong, A; Sadigh, B; Sterne, P et al.
Partner: UNT Libraries Government Documents Department
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INCCA: Integrated Climate and Carbon

Description: The INCCA (Integrated Climate and Carbon) initiative will develop and apply the ability to simulate the fate and climate impact of fossil fuel-derived carbon dioxide (CO{sub 2}) and aerosols on a global scale. Coupled climate and carbon cycle modeling like that proposed for INCCA is required to understand and predict the future environmental impacts of fossil fuel burning. At present, atmospheric CO{sub 2} concentrations are prescribed, not simulated, in large climate models. Credible simulations of the entire climate system, however, need to predict time-evolving atmospheric greenhouse forcing using anthropogenic emissions as the fundamental input. Predicting atmospheric COS concentrations represents a substantial scientific advance because there are large natural sources and sinks of carbon that are likely to change as a result of climate change. Both terrestrial (e.g., vegetation on land) and oceanic components of the carbon cycle are known to be sensitive to climate change. Estimates of the amount of man-made CO{sub 2} that will accumulate in the atmosphere depend on understanding the carbon cycle. For this reason, models that use CO{sub 2} emissions, not prescribed atmospheric concentrations, as fundamental inputs are required to directly address greenhouse-related questions of interest to policymakers. INCCA is uniquely positioned to make rapid progress in this high-priority area of global change modeling and prediction because we can leverage previous and ongoing LLNL developments, and use existing component models that are well-developed and published. The need for a vastly improved carbon dioxide prediction capability is appreciated by the DOE. As the US Accelerated Climate Prediction Initiative (ACPI) progresses, we expect the DOE will emphasize the carbon cycle as the next major department-level earth science focus. INCCA will position LLNL for substantial additional funding as this new focus is realized. In the limited time since our LDRD funding was first received (1 November 2000) we have …
Date: March 13, 2001
Creator: Thompson, S. L.
Partner: UNT Libraries Government Documents Department
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NIF Inert Gas/Vacuum Management Prestart Review Phase 3 - Permit Spatial Filter Vacuum

Description: A Management Prestart Review (MPR) for the National Ignition Facility (NIF) vacuum testing of spatial filters, the Cavity Spatial Filter (CSF) and the Transport Spatial Filter (TSF), was conducted during March 2001. The review was performed to determine the readiness of the Beamline Infrastucture System (BIS) team and the Integration Management and Installation (IMI) contractor to start the vacuum testing of the components and assemblies that constitute the four CSF clusters and four TSF clusters in the NIF laser. This review assures that appropriate engineering, planning and management is in place to start this testing. Completion and acceptance of this report satisfies the LLNL requirement for MPRs to be conducted whenever a significant new risk is introduced into a project and is an essential part of the ISM work authorization process.
Date: March 1, 2001
Creator: Williams, J.; Beavers, T.; Bryan, S.; Hermes, G. & Patton, H.
Partner: UNT Libraries Government Documents Department
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User Manual for LLNL's 24-Chamber Instrument (a.k.a. PolyHanaa)

Description: The 24 chamber instrument, called the PolyHanaa, is designed to perform rapid, real-time detection of biological agents using the Polymerase Chain Reaction (PCR) process. Liquid samples are pipetted into small, disposable polypropylene inserts which are placed into each of the 24 thermal cycling chambers.
Date: March 29, 2001
Creator: Richards, J
Partner: UNT Libraries Government Documents Department
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Low Charge-State AMS for Biological Research

Description: University collaborations and internal research programs that trace isotopically labeled compounds in natural biological systems have grown significantly in the past few years. New research in molecular nutrition, protein sequencing, immunoassays, and toxicology now require hundreds to thousands of sample analyses per project. The goal of this effort was to strengthen this Laboratory and University health related research by the expansion of AMS access. This was achieved by our design and implementation of an AMS spectrometer that analyzes isotopic ions at lower energies in a more compact spectrometer without sacrificing precision or throughput. The decrease in ion energies is accompanied by a significant reduction in size and cost of the spectrometer. Our successful reduction in spectrometer cost, operation, and space will make this technology more appealing to research institutions, including industrial research centers. While others have also developed smaller spectrometers, these are limited in precision and throughput by the much lower intensities of ion beams that can be transmitted through them without differential loss of isotope species. The primary challenge in this project was mating the LLNL-designed high intensity negative ion source (Roberts, et al. 1994; Southon & Roberts, 2000) to available accelerator components and then showing that the precision and throughput would remain high enough to serve the research that needs large numbers of AMS analyses. The project also required reduction in operating complexity so that scientists and students would not require technical specialists to make their measurements. This report describes the experiments done to assure the needed spectrometer performance.
Date: March 1, 2001
Creator: Vogel, John S.; Ognibene, Theodore; Roberts, Mark; Brown, Thomas; Clifford, Andrew; Espinosa, Daniel et al.
Partner: UNT Libraries Government Documents Department
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Gas Generation from K East Basin Sludges - Series II Testing

Description: This report describes work to examine the gas generation behavior of actual K East (KE) Basin floor, pit and canister sludge. Mixed and unmixed and fractionated KE canister sludge were tested, along with floor and pit sludges from areas in the KE Basin not previously sampled. The first report in this series focused on gas generation from KE floor and canister sludge collected using a consolidated sampling technique. The third report will present results of gas generation testing of irradiated uranium fuel fragments with and without sludge addition. The path forward for management of the K Basin Sludge is to retrieve, ship, and store the sludge at T Plant until final processing at some future date. Gas generation will impact the designs and costs of systems associated with retrieval, transportation and storage of sludge.
Date: March 14, 2001
Creator: Bryan, Samuel A.; Delegard, Calvin H.; Schmidt, Andrew J.; Sell, Rachel L.; Silvers, Kurt L.; Gano, Susan R. et al.
Partner: UNT Libraries Government Documents Department
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Novel Parallel Numerical Methods for Radiation& Neutron Transport

Description: In many of the multiphysics simulations performed at LLNL, transport calculations can take up 30 to 50% of the total run time. If Monte Carlo methods are used, the percentage can be as high as 80%. Thus, a significant core competence in the formulation, software implementation, and solution of the numerical problems arising in transport modeling is essential to Laboratory and DOE research. In this project, we worked on developing scalable solution methods for the equations that model the transport of photons and neutrons through materials. Our goal was to reduce the transport solve time in these simulations by means of more advanced numerical methods and their parallel implementations. These methods must be scalable, that is, the time to solution must remain constant as the problem size grows and additional computer resources are used. For iterative methods, scalability requires that (1) the number of iterations to reach convergence is independent of problem size, and (2) that the computational cost grows linearly with problem size. We focused on deterministic approaches to transport, building on our earlier work in which we performed a new, detailed analysis of some existing transport methods and developed new approaches. The Boltzmann equation (the underlying equation to be solved) and various solution methods have been developed over many years. Consequently, many laboratory codes are based on these methods, which are in some cases decades old. For the transport of x-rays through partially ionized plasmas in local thermodynamic equilibrium, the transport equation is coupled to nonlinear diffusion equations for the electron and ion temperatures via the highly nonlinear Planck function. We investigated the suitability of traditional-solution approaches to transport on terascale architectures and also designed new scalable algorithms; in some cases, we investigated hybrid approaches that combined both.
Date: March 6, 2001
Creator: Brown, P N
Partner: UNT Libraries Government Documents Department
open access

Laser Science & Technology Program Annual Report - 2000

Description: The Laser Science and Technology (LS&T) Program Annual Report 2001 provides documentation of the achievements of the LLNL LS&T Program during the April 2001 to March 2002 period using three formats: (1) an Overview that is a narrative summary of important results for the year; (2) brief summaries of research and development activity highlights within the four Program elements: Advanced Lasers and Components (AL&C), Laser Optics and Materials (LO&M), Short Pulse Laser Applications and Technologies (SPLAT), and High-Energy Laser System and Tests (HELST); and (3) a compilation of selected articles and technical reports published in reputable scientific or technology journals in this period. All three elements (Annual Overview, Activity Highlights, and Technical Reports) are also on the Web: http://laser.llnl.gov/lasers/pubs/icfq.html. The underlying mission for the LS&T Program is to develop advanced lasers, optics, and materials technologies and applications to solve problems and create new capabilities of importance to the Laboratory and the nation. This mission statement has been our guide for defining work appropriate for our Program. A major new focus of LS&T beginning this past year has been the development of high peak power short-pulse capability for the National Ignition Facility (NIF). LS&T is committed to this activity.
Date: March 20, 2001
Creator: Chen, H. L.
Partner: UNT Libraries Government Documents Department
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Identification and Elimination of Mechanisms Leading to UV Damage of DKDP

Description: This LDRD project addressed both bulk and surface damage induced by UV-laser exposure. The primary objectives were (1) to complete our understanding of the factors leading to bulk damage, including growth conditions and orientational direction, and (2) to identify mechanisms of surface damage initiation and growth leading to mitigation methods. Due to the more advanced state of knowledge in bulk damage, a greater portion of that work was completed during the one-year term of this project. Three papers were presented at the 32nd Boulder Damage Symposium on Laser-Induced Damage in Optical Materials, and the three resulting manuscripts submitted to the Proceeding are attached: An important result from this work is that it established a dependence of obscuration from bulk damage on fluence and pulse length, which is shown.
Date: March 6, 2001
Creator: Burnham, A; Runkel, M; Chase, L; Demos, S; Staggs, M & Siekhaus, W
Partner: UNT Libraries Government Documents Department
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Flibe Coolant Cleanup and Processing in the HYLIFE-II Inertial Fusion Energy Power Plant

Description: In the HYLIFE-II chamber design, a thick flowing blanket of molten-salt (Li{sub 2}BeF{sub 4}) called flibe is used to protect structures from radiation damage. Since it is directly exposed to the fusion target, the flibe will absorb the target debris. Removing the materials left over from target explosions at the rate of {approx}6/s and then recycling some of these materials poses a challenge for the inertial fusion energy power plant. The choice of target materials derives from multi-disciplinary criteria such as target performance, fabricability, safety and environment, corrosion, and cost of recycle. Indirect-drive targets require high-2 materials for the hohlraum. Gold and gadolinium are favorite target materials for laboratory experiments but cost considerations may preclude their use in power plants or at least requires cost effective recycle because a year's supply of gold and gadolinium is estimated at 520 M$ and 40 M$. Environmental and waste considerations alone require recycle of this material. Separation by volatility appears to be the most attractive (e.g., Hg and Xe); centrifugation (e.g., Pb) is acceptable with some problems (e.g., materials compatibility) and chemical separation is the least attractive (e.g. Gd and Hf). Mercury, hafnium and xenon might be substituted with equal target performance and have advantages in removal and recycle due to their high volatility, except for hafnium. Alternatively, lead, tungsten and xenon might be used due to the ability to use centrifugation and gaseous separation. Hafnium or tantalum form fluorides, which will complicate materials compatibility, corrosion and require sufficient volatility of the fluoride for separation. Further complicating the coolant cleanup and processing is the formation of free fluorine due to nuclear transformation of lithium and beryllium in the flibe, which requires chemical control of the fluoride level to minimize corrosion. The study of the choice of target materials and the appropriate processing needs …
Date: March 23, 2001
Creator: Moir, R W
Partner: UNT Libraries Government Documents Department
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