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Laboratory Directed Research and Development Program FY 2001

Description: The Ernest Orlando Lawrence Berkeley National Laboratory (Berkeley Lab or LBNL) is a multi-program national research facility operated by the University of California for the Department of Energy (DOE). As an integral element of DOE's National Laboratory System, Berkeley Lab supports DOE's missions in fundamental science, energy resources, and environmental quality. Berkeley Lab programs advance four distinct goals for DOE and the nation: (1) To perform leading multidisciplinary research in the computing sciences, physical sciences, energy sciences, biosciences, and general sciences in a manner that ensures employee and public safety and protection of the environment. (2) To develop and operate unique national experimental facilities for qualified investigators. (3) To educate and train future generations of scientists and engineers to promote national science and education goals. (4) To transfer knowledge and technological innovations and to foster productive relationships among Berkeley Lab's research programs, universities, and industry in order to promote national economic competitiveness. This is the annual report on Laboratory Directed Research and Development (LDRD) program for FY01.
Date: March 15, 2002
Creator: Hansen, Todd & Levy, Karin
Partner: UNT Libraries Government Documents Department

SUSY dark matter and non-universal gaugino masses

Description: In this talk the authors investigate the dark matter prospects for supersymmetric models with non-universal gaugino masses. They motivate the use of non-universal gaugino masses from several directions, including problems, with the current favorite scenario, the cMSSM. They then display new corridors of parameter space that allow an acceptable dark matter relic density once gaugino mass universality is relaxed. They finish with a specific string-derived model that allows this universality relaxation and then use the dark matter constraint to make specific statements about the hidden sector of the model.
Date: April 15, 2002
Creator: Birkedal-Hansen, Andreas
Partner: UNT Libraries Government Documents Department

Object-Oriented Analysis Code for Hall A Vertical Drift Chambers

Description: The high-resolution spectrometers in Jefferson Lab's Hall A use vertical drift chambers to determine charged particle tracks. The current analysis code for the vertical drift chambers is difficult to maintain and modify, which has prompted the development of an object-oriented version, which will be easier to maintain and more able to adapt to changes in the detector configuration. However, the object-oriented approach involves using a slightly different algorithm than ESPACE, which could lead to different results. In this project, a preliminary version of an object-oriented analysis program for the vertical drift chambers is created and its results are compared to the existing software to determine the impacts of the differences in the reconstruction algorithms. In addition, the algorithms themselves are compared, and minor differences in track reconstruction techniques are reported.
Date: January 1, 2002
Creator: Robbins, J. & Hansen, J.O.
Partner: UNT Libraries Government Documents Department

The Effect of pH on Nickel Alloy SCC and Corrosion Performance

Description: Alloy X-750 condition HTH stress corrosion crack growth rate (SCCGR) tests have been conducted at 360 C (680 F) with 50 cc/kg hydrogen as a function of coolant pH. Results indicate no appreciable influence of pH on crack growth in the pH (at 360 C) range of {approx} 6.2 to 8.7, consistent with previous alloy 600 findings. These intermediate pH results suggest that pH is not a key variable which must be accounted for when modeling pressurized water reactor (PWR) primary water SCC. In this study, however, a nearly three fold reduction in X-750 crack growth rate was observed in reduced pH environments (pH 3.8 through HCl addition and pH 4-5.3 through H{sub 2}SO{sub 4} addition). Crack growth rates did not directly correlate with corrosion film thickness. In fact, 10x thicker corrosion films were observed in the reduced pH environments.
Date: October 10, 2002
Creator: Morton, D.S. & Hansen, M.
Partner: UNT Libraries Government Documents Department

Vegetation Change Analysis User's Manual

Description: Approximately 70 percent of all U.S. military training lands are located in arid and semi-arid areas. Training activities in such areas frequently adversely affect vegetation, damaging plants and reducing the resilience of vegetation to recover once disturbed. Fugitive dust resulting from a loss of vegetation creates additional problems for human health, increasing accidents due to decreased visibility, and increasing maintenance costs for roads, vehicles, and equipment. Diagnostic techniques are needed to identify thresholds of sustainable military use. A cooperative effort among U.S. Department of Energy, U.S. Department of Defense, and selected university scientists was undertaken to focus on developing new techniques for monitoring and mitigating military impacts in arid lands. This manual focuses on the development of new monitoring techniques that have been implemented at Fort Irwin, California. New mitigation techniques are described in a separate companion manual. This User's Manual is designed to address diagnostic capabilities needed to distinguish between various degrees of sustainable and nonsustainable impacts due to military training and testing and habitat-disturbing activities in desert ecosystems. Techniques described here focus on the use of high-resolution imagery and the application of image-processing techniques developed primarily for medical research. A discussion is provided about the measurement of plant biomass and shrub canopy cover in arid. lands using conventional methods. Both semiquantitative methods and quantitative methods are discussed and reference to current literature is provided. A background about the use of digital imagery to measure vegetation is presented.
Date: October 2002
Creator: Hansen, D. J. & Ostler, W. K.
Partner: UNT Libraries Government Documents Department

Introduction to Methods Demonstrations for Authentication

Description: During the Trilateral Initiative Technical Workshop on Authentication & Certification, PNNL will demonstrate some authentication technologies. This paper briefly describes the motivation for these demonstrations and provide background on them.
Date: July 15, 2002
Creator: Kouzes, Richard T.; Hansen, Randy R. & Pitts, W. K.
Partner: UNT Libraries Government Documents Department

Commercial Decommissioning at DOE's Rocky Flats

Description: Due in large part to the number of nuclear facilities that make up the DOE complex, DOE-EM work has historically been paperwork intensive and driven by extensive regulations. Requirements for non-nuclear facilities are often grouped with those of nuclear facilities, driving up costs. Kaiser-Hill was interested in applying a commercial model to demolition of these facilities and wanted to apply necessary and sufficient standards to the work activities, but avoid applying unnecessary requirements. Faced with demolishing hundreds of uncontaminated or non-radiologically contaminated facilities, Kaiser-Hill has developed a subcontracting strategy to drastically reduce the cost of demolishing these facilities at Rocky Flats. Aiming to tailor the demolition approach of such facilities to more closely follow commercial practices, Kaiser-Hill recently released a Request for Proposals (RFP) for the demolition of the site's former central administration facility. The RFP significantly reduced requirements for compliance with specific DOE directives. Instead, the RFP required subcontractors to comply with health and safety requirements commonly found in the demolition of similar facilities in a commercial setting. This resulted in a number of bids from companies who have normally not bid on DOE work previously and at a reduced cost over previous approaches. This paper will discuss the details of this subcontracting strategy.
Date: February 25, 2002
Creator: Freiboth, C.; Sandlin, N.; Schubert, A. & Hansen, S.
Partner: UNT Libraries Government Documents Department

Pre-treating Seed to Enhance Germination of Desert Shrubs

Description: Creosotebush [Larrea tridentata (D.C.) Cav.] and white bursage [Ambrosia dumosa (A. Gray) W.W. Payne] seeds were subjected to pre-treatments of rinsing and soaking in water and thiourea to enhance germination in laboratory experiments. The effects of darkness, temperature, seed source, and soil moisture were also evaluated in the laboratory. The best pre-treatment from the laboratory experiments, rinsing with water for 36 hours followed by drying, was field-tested at Fort Irwin, California. Two sites and two seeding dates (early March and mid April) were determined for each site. Five mulch treatments (no mulch, straw, gravel, chemical stabilizer, and plastic) were evaluated in combination with the seed pre-treatments. Field emergence was greatly enhanced with the seed pre-treatment for white bursage during the March (18-42% increase in germination) and April seedings (16-23% increase in germination). Creosotebush showed poor germination during March (2-5%) when soil temperatures averaged 15 C, but germination increased during the April trials (6-43%) when soil temperatures averaged 23 C. The seed pre-treatment during the April trials increased germination from 16-23%. The plastic mulch treatment increased germination dramatically during both the March and April trials. The plastic mulch increased soil temperatures (8-10 C)and maintained high humidity during germination. Both the chemical stabilizer and the gravel mulches improved germination over the control while the straw mulch decreased germination. These results suggest that seed pre-treatments combined with irrigation and mulch are effective techniques to establish these two dominant Mojave Desert species from seed.
Date: June 1, 2002
Creator: Ostler, W. K.; Anderson, D. C. & Hansen, D. J.
Partner: UNT Libraries Government Documents Department

Habitats at Risk: Global Warming and Species Loss in Globally Significant Terrestrial Ecosystems

Description: This report studies how global warming could affect the planet's "crown jewels" of nature and rates Canada among those most vulnerable. Released by the David Suzuki Foundation and the World Wildlife Fund, the report highlights the urgent need to reduce greenhouse gas emissions.
Date: February 2002
Creator: Malcolm, Jay R.; Liu, Canran; Miller, Laurie B.; Allutt, Tom & Hansen, Lara
Partner: UNT Libraries

The D0 solenoid NMR magnetometer

Description: A field monitoring system for the 2 Tesla Solenoid of the D0 detector is described. It is comprised of a very small NMR probe cabled to a DSP based signal processing board. The design magnetic field range is from 1.0 to 2.2 Tesla, corresponding to an RF frequency range of 42.57 to 93.67 MHz. The desired an accuracy is one part in 10{sup 5}. To minimize material in the interaction region of the D0 detector, the overall thickness of the NMR probe is 4 mm, including its mounting plate, and its width is 10 mm. To minimize cable mass, 4mm diameter IMR-100A cables are used for transmitting the RF signals from a nearby patch panel 25 meters to each of four probes mounted within the bore of the solenoid. RG213U cables 45 meters long are used to send the RF from the movable counting house to the patch panel. With this setup, the detector signal voltage at the moving counting room is in the range of 250-400 mV.
Date: November 20, 2002
Creator: Sten Uldall Hansen Terry Kiper, Tom Regan, John Lofgren et al.
Partner: UNT Libraries Government Documents Department

Apparatus and Method for Increasing the Diameter of Metal Alloy Wires Within a Molten Metal Pool

Description: In a dip forming process the core material to be coated is introduced directly into a source block of coating material eliminating the need for a bushing entrance component. The process containment vessel or crucible is heated so that only a portion of the coating material becomes molten, leaving a solid portion of material as the entrance port of, and seal around, the core material. The crucible can contain molten and solid metals and is especially useful when coating core material with reactive metals. The source block of coating material has been machined to include a close tolerance hole of a size and shape to closely fit the core material. The core material moves first through the solid portion of the source block of coating material where the close tolerance hole has been machined, then through a solid/molten interface, and finally through the molten phase where the diameter of the core material is increased. The crucible may or may not require water-cooling depending upon the type of material used in crucible construction. The system may operate under vacuum, partial vacuum, atmospheric pressure, or positive pressure depending upon the type of source material being used.
Date: January 29, 2002
Creator: Hartman, Alan D.; Argetsinger, Edward R.; Hansen, Jeffrey S.; Paige, Jack I.; King, Paul E. & Turner, Paul C.
Partner: UNT Libraries Government Documents Department

Large historical changes of fossil-fuel black carbon aerosols

Description: Anthropogenic emissions of fine black carbon (BC) particles, the principal light-absorbing atmospheric aerosol, have varied during the past century in response to changes of fossil-fuel utilization, technology developments, and emission controls. We estimate historical trends of fossil-fuel BC emissions in six regions that represent about two-thirds of present day emissions and extrapolate these to global emissions from 1875 onward. Qualitative features in these trends show rapid increase in the latter part of the 1800s, the leveling off in the first half of the 1900s, and the re-acceleration in the past 50 years as China and India developed. We find that historical changes of fuel utilization have caused large temporal change in aerosol absorption, and thus substantial change of aerosol single scatter albedo in some regions, which suggests that BC may have contributed to global temperature changes in the past century. This implies that the BC history needs to be represented realistically in climate change assessments.
Date: September 26, 2002
Creator: Novakov, T.; Ramanathan, V.; Hansen, J.E.; Kirchstetter, T.W.; Sato, M.; Sinton, J.E. et al.
Partner: UNT Libraries Government Documents Department

Technology Development, Evaluation, and Application (TDEA) FY 2001 Progress Report Environment, Safety, and Health (ESH) Division

Description: This progress report presents the results of 11 projects funded ($500K) in FY01 by the Technology Development, Evaluation, and Application (TDEA) Committee of the Environment, Safety, and Health Division (ESH). Five projects fit into the Health Physics discipline, 5 projects are environmental science and one is industrial hygiene/safety. As a result of their TDEA-funded projects, investigators have published sixteen papers in professional journals, proceedings, or Los Alamos reports and presented their work at professional meetings. Supplement funds and in-kind contributions, such as staff time, instrument use, and workspace, were also provided to TDEA-funded projects by organizations external to ESH Divisions.
Date: May 1, 2002
Creator: Hoffman, L.G.; Alvar, K.; Buhl, T.; Foltyn, E.; Hansen, W.; Erdal, B. et al.
Partner: UNT Libraries Government Documents Department

Dopant and self-diffusion in extrinsic n-type silicon isotopically controlled heterostructures

Description: We present experimental results of dopant- and self-diffusion in extrinsic silicon doped with As. Multilayers of isotopically controlled {sup 28}Si and natural silicon enable simultaneous analysis of {sup 30}Si diffusion into the {sup 28}Si enriched layers and dopant diffusion throughout the multilayer structure. In order to suppress transient enhanced self- and dopant diffusion caused by ion implantation, we adopted a special approach to dopant introduction. First, an amorphous 250-nm thick Si layer was deposited on top of the Si isotope heterostructure. Then the dopant ions were implanted to a depth such that all the radiation damage resided inside this amorphous cap layer. These samples were annealed for various times and temperatures to study the impact of As diffusion and doping on Si self-diffusion. The Si self-diffusion coefficient and the dopant diffusivity for various extrinsic n-type conditions were determined over a wide temperature range. We observed increased diffusivities that we attribute to the increase in the concentration of the native defect promoting the diffusion.
Date: April 1, 2002
Creator: Silvestri, Hughes H.; Sharp, Ian D.; Bracht, Hartmut A.; Nicols, Sam P.; Beeman, Jeff W.; Hansen, John et al.
Partner: UNT Libraries Government Documents Department

Self- and dopant diffusion in extrinsic boron doped isotopically controlled silicon multilayer structures

Description: Isotopically controlled silicon multilayer structures were used to measure the enhancement of self- and dopant diffusion in extrinsic boron doped silicon. {sup 30}Si was used as a tracer through a multilayer structure of alternating natural Si and enriched {sup 28}Si layers. Low energy, high resolution secondary ion mass spectrometry (SIMS) allowed for simultaneous measurement of self- and dopant diffusion profiles of samples annealed at temperatures between 850 C and 1100 C. A specially designed ion- implanted amorphous Si surface layer was used as a dopant source to suppress excess defects in the multilayer structure, thereby eliminating transient enhanced diffusion (TED) behavior. Self- and dopant diffusion coefficients, diffusion mechanisms, and native defect charge states were determined from computer-aided modeling, based on differential equations describing the diffusion processes. We present a quantitative description of B diffusion enhanced self-diffusion in silicon and conclude that the diffusion of both B and Si is mainly mediated by neutral and singly positively charged self-interstitials under p-type doping. No significant contribution of vacancies to either B or Si diffusion is observed.
Date: April 1, 2002
Creator: Sharp, Ian D.; Bracht, Hartmut A.; Silvestri, Hughes H.; Nicols, Samuel P.; Beeman, Jeffrey W.; Hansen, John L. et al.
Partner: UNT Libraries Government Documents Department

One-piece, composite crucible with integral withdrawal/discharge section

Description: A one-piece, composite open-bottom casting mold with integral withdrawal section is fabricated by thermal spraying of materials compatible with and used for the continuous casting of shaped products of reactive metals and alloys such as, for example, titanium and its alloys or for the gas atomization thereof.
Date: July 30, 2002
Creator: Besser, Matthew (Iowa State Univ., Ames, IA); Terpstra, Robert L. (Iowa State Univ., Ames, IA); Sordelet, Daniel J. (Iowa State Univ., Ames, IA); Anderson, Iver E. (Iowa State Univ., Ames, IA); Hartman, Alan D.; Argetsinger, Edward R. et al.
Partner: UNT Libraries Government Documents Department

Hyperon-nucleon bound states and electroproduction of strangeness on light nuclei.

Description: The A(e,e{prime}K{sup +})Y X reaction has been investigated in Hall C at Jefferson Lab. Data were taken for Q{sup 2} {approx} 0.35 and 0.5 GeV{sup 2} at a beam energy of 3.245 GeV for {sup 1}H, {sup 2}H, {sup 3}He and {sup 4}He, C and Al targets. The missing mass spectra are fitted with Monte Carlo simulations including {Lambda}, {Sigma}{sup 0}, {Sigma}{sup -} hyperon production. Models for quasifree production are compared to the data, excess yields close to threshold are attributed to FSI. Evidence for {Lambda}-hypernuclear bound states is seen for {sup 3,4}He targets.
Date: June 25, 2002
Creator: Dohrmann, F.; Abbott, D.; Ahmidouch, A.; Ambrozewicz, P.; Armstrong, C. S.; Arrington, J. et al.
Partner: UNT Libraries Government Documents Department

Electroproduction of strangeness on light nuclei.

Description: The A(e,e{prime} K{sup +})YX reaction has been investigated in Hall C at Jefferson Laboratory for 6 different targets. Data were taken for Q{sup 2} {approx} 0.35 and 0.5 GeV{sup 2} at a beam energy of 3.245 GeV for {sup 1}H, {sup 2}H, {sup 3}He, {sup 4}He, C and Al targets. The missing mass spectra are fitted with Monte Carlo simulations taking into account the production of {Lambda} and {Sigma}{sup 0} hyperon production off the proton, and {Sigma}{sup -} off the neutron. Models for quasifree production are compared to the data, excess yields close to threshold are attributed to FSI. Evidence for {Lambda}-hypernuclear bound states is seen for {sup 3,4}He targets.
Date: May 16, 2002
Creator: Dohrmann, F.; Abbott, D.; Ahmidouch, A.; Ambrozewicz, P.; Armstrong, C. S.; Arrington, J. et al.
Partner: UNT Libraries Government Documents Department

Polarization Transfer in the He-4(polarized-e, e-prime polarized-p)H-3 Reaction up to Q{sup 2}=2.6 (GeV/c){sup 2}

Description: We have measured the proton recoil polarization in the {sup 4}He(polarized-e, e-prime, p){sup 3}H reaction at Q{sup 2} = 0.5, 1.0, 1.6, and 2.6 (GeV/c){sup 2}. The measured ratio of polarization transfer coefficients differs from a fully relativistic calculation, favoring the inclusion of a predicted medium modification of the proton form factors based on a quark-meson coupling model. In contrast, the measured induced polarizations agree reasonably well with the fully relativistic calculation indicating that the treatment of final-state interactions is under control.
Date: November 1, 2002
Creator: Strauch, S.; Dieterich, S.; Aniol, K.A.; Annand, J.R.M.; Baker, O.K.; Bertozzi, W. et al.
Partner: UNT Libraries Government Documents Department