Transmission electron microscopy of oxide dispersion strengthened (ODS) molybdenum: effects of irradiation on material microstructure (open access)

Transmission electron microscopy of oxide dispersion strengthened (ODS) molybdenum: effects of irradiation on material microstructure

Oxide dispersion strengthened (ODS) molybdenum has been characterized using transmission electron microscopy (TEM) to determine the effects of irradiation on material microstructure. This work describes the results-to-date from TEM characterization of unirradiated and irradiated ODS molybdenum. The general microstructure of the unirradiated material consists of fine molybdenum grains (< 5 {micro}m average grain size) with numerous low angle boundaries and isolated dislocation networks. 'Ribbon'-like lanthanum oxides are aligned along the working direction of the product form and are frequently associated with grain boundaries, serving to inhibit grain boundary and dislocation movement. In addition to the 'ribbons', discrete lanthanum oxide particles have also been detected. After irradiation, the material is characterized by the presence of nonuniformly distributed large ({approx} 20 to 100 nm in diameter), multi-faceted voids, while the molybdenum grain size and oxide morphology appear to be unaffected by irradiation.
Date: March 3, 2003
Creator: Baranwal, R. and Burke, M.G.
Object Type: Report
System: The UNT Digital Library
Hydrologic Tests at Characterization Wells R-9i, R-13, R-19, R-22, and R-31 (open access)

Hydrologic Tests at Characterization Wells R-9i, R-13, R-19, R-22, and R-31

Hydrologic information is essential for environmental efforts at Los Alamos National Laboratory. Testing at new characterization wells being drilled to the regional aquifer (''R wells'') to improve the conceptual hydrogeologic model of the Pajarito Plateau is providing such information. Drilling has been by air-rotary casing-advance or open-hole methods. Most wells are completed with multiple screens. After their construction, wells were rigorously developed by wire-brushing, bailing, followed by surging, swabbing, or jetting, and finally by pumping. These methods are effective based on field-parameter measurements and comparison of results of hydrologic testing at well R-31 before and after complete well development. We conducted field tests on various zones of saturation penetrated by the R wells to collect data needed for determining hydraulic properties. This document provides details of the design and execution of testing as well as an analysis of data for five of the new wells: R-9i, R-13, R-19, R-22, and R-31. One well was evaluated by a pumping test (R-13), another was evaluated by both straddle-packer/injection and pumping tests (R-9i), and the rest were evaluated by injection tests alone (R-19, R-22, R-31). Testing was constrained by the regional setting (complex geology and multiple zones of saturation) and well construction (multiscreen …
Date: March 1, 2003
Creator: Stone, W.J. & McLin, S.
Object Type: Report
System: The UNT Digital Library
Biomonitoring with Wireless Communications (open access)

Biomonitoring with Wireless Communications

This review is divided into three sections: technologies for monitoring physiological parameters; biosensors for chemical assays and wireless communications technologies including image transmissions. Applications range from monitoring high risk patients for heart, respiratory activity and falls to sensing levels of physical activity in military, rescue, and sports personnel. The range of measurements include, heart rate, pulse wave form, respiratory rate, blood oxygen, tissue pCO2, exhaled carbon dioxide and physical activity. Other feasible measurements will employ miniature chemical laboratories on silicon or plastic chips. The measurements can be extended to clinical chemical assays ranging from common blood assays to protein or specialized protein measurements (e.g., troponin, creatine, and cytokines such as TNF and IL6). Though the feasibility of using wireless technology to communicate vital signs has been demonstrated 32 years ago (1) it has been only recently that practical and portable devices and communications net works have become generally available for inexpensive deployment of comfortable and affordable devices and systems.
Date: March 1, 2003
Creator: Budinger, Thomas F.
Object Type: Article
System: The UNT Digital Library
Frequency Control Concerns in the North American Electric Power System (open access)

Frequency Control Concerns in the North American Electric Power System

This paper examines the relationship between system frequency, reliability and markets. It was prompted by the frequency deviations recently experienced at 2200 hours daily but is more generally concerned with the question of what frequency control is necessary. The paper does not provide new information or document new research. Nor is it intended to educate readers concerning power system engineering. Instead, the purpose is to reexamine well known truths concerning the power system and to freshly explore the basic relationship between frequency, reliability and markets: stepping back, if you will, to see if we are collectively missing something. The concern of this paper is with frequency and reliability. Off-nominal frequency can impact reliability and markets efficiency (as we are using the term here) in four ways. It could damage equipment (generation, transmission, or load). It could degrade the quality of the product being delivered to end users (too low and lights would flicker unacceptably, for example). It could result in the collapse of the power system itself (by triggering protective system actions, for example). Or it could result in overloading transmission lines as various generators try to restore system frequency impacting markets efficiency. Often these causes operate in concert. Generator …
Date: March 26, 2003
Creator: Kirby, B.J.
Object Type: Report
System: The UNT Digital Library
Results of Deposition Scoping Tests (open access)

Results of Deposition Scoping Tests

The processes of crystallization and solid deposit formation that led to the shutdown of the 2H evaporator operation at the Savannah River Site (SRS) and that could possibly cause similar problems in the future or in other evaporators need to be better understood. Through experimentation, thermodynamic modeling, and correlation of scaling to historical tank farm operations, progress has been made in developing guidelines as to the concentrations of silicon and aluminum that can be processed by evaporators while avoiding unacceptable levels of scale formation. However, because of limitations of the thermodynamic model and an insufficient amount of operational data at slightly supersaturated concentration levels, uncertainty still exists regarding acceptable feed concentrations. The objective of this effort is to provide information that can be used in defining acceptable levels of silicon and aluminum in evaporator feed solutions. Data collected previously showed that particle formation reactions can be rapid at evaporator temperatures for elevated silicon and aluminum concentrations. However, insufficient data exists to estimate the silicon and aluminum concentrations above which solids will form in the time frame of evaporator processing. The work described in this report was designed to determine the induction period for solutions of decreasing aluminum and silicon concentration …
Date: March 4, 2003
Creator: Hu, M.Z.
Object Type: Report
System: The UNT Digital Library
EOSN: A TOUGH2 module for noble gases (open access)

EOSN: A TOUGH2 module for noble gases

We developed a new fluid property module for TOUGH2, called EOSN, to simulate transport of noble gases in the subsurface. Currently, users may select any of five different noble gases as well as CO2, two at a time. For the three gas components (air and two user-specified noble gases) in EOSN, the Henry's coefficients and the diffusivities in the gas phase are no longer assumed constants, but are temperature dependent. We used the Crovetto et al. (1982) model to estimate Henry's coefficients, and the Reid et al. (1987) correlations to calculate gas phase diffusivities. The new module requires users to provide names of the selected noble gases, which properties are provided internally. There are options for users to specify any (non-zero) molecular weights and half-lives for the gas components. We provide two examples to show applications of TOUGH2IEOSN. While temperature effects are relatively insignificant for one example problem where advection is dominant, they cause almost an order of magnitude difference for the other case where diffusion becomes a dominant process and temperature variations are relatively large. It appears that thermodynamic effects on gas diffusivities and Henry's coefficients can be important for low-permeability porous media and zones with large temperature variations.
Date: March 7, 2003
Creator: Shan, Chao & Pruess, Karsten
Object Type: Report
System: The UNT Digital Library
Plutonium/High-Level Vitrified Waste Bdbe Dose Calculation (open access)

Plutonium/High-Level Vitrified Waste Bdbe Dose Calculation

In accordance with the Nuclear Waste Policy Amendments Act of 1987, Yucca Mountain was designated as the site to be investigated as a potential repository for the disposal of high-level radioactive waste. The Yucca Mountain site is an undeveloped area located on the southwestern edge of the Nevada Test Site (NTS), about 100 miles northwest of Las Vegas. The site currently lacks rail service or an existing right-of-way. If the Yucca Mountain site is found suitable for the repository, rail service is desirable to the Office of Civilian Waste Management (OCRWM) Program because of the potential of rail transportation to reduce costs and to reduce the number of shipments relative to highway transportation. A Preliminary Rail Access Study evaluated 13 potential rail spur options. Alternative routes within the major options were also developed. Each of these options was then evaluated for potential land use conflicts and access to regional rail carriers. Three potential routes having few land use conflicts and having access to regional carriers were recommended for further investigation. Figure 1-1 shows these three routes. The Jean route is estimated to be about 120 miles long, the Carlin route to be about 365 miles long, and Caliente route to …
Date: March 19, 2003
Creator: Richardson, D. C.
Object Type: Report
System: The UNT Digital Library
Improving the Efficiency of Solid State Light Sources (open access)

Improving the Efficiency of Solid State Light Sources

This proposal addresses the national need to develop a high efficiency light source for general illumination applications. The goal is to perform research that would lead to the fabrication of a unique solid state, white-emitting light source. This source is based on an InGaN/GaN UV-emitting chip that activates a luminescent material (phosphor) to produce white light. White-light LEDs are commercially available which use UV from a GaN chip to excite a phosphor suspended in epoxy around the chip. Currently, these devices are relatively inefficient. This research will target one technical barrier that presently limits the efficiency of GaN based devices. Improvements in efficiencies will be achieved by improving the internal conversion efficiency of the LED die, by improving the coupling between the die and phosphor(s) to reduce losses at the surfaces, and by selecting phosphors to maximize the emissions from the LEDs in conversion to white light. The UCSD research team proposes for this project to develop new phosphors that have high quantum efficiencies that can be activated by the UV-blue (360-410 nm) light emitted by the GaN device. The main goal for the UCSD team was to develop new phosphor materials with a very specific property: phosphors that could …
Date: March 31, 2003
Creator: McKittrick, Joanna
Object Type: Report
System: The UNT Digital Library
The Forcing of Mercury Oxidation as a Means of Promoting Low-Cost Capture (open access)

The Forcing of Mercury Oxidation as a Means of Promoting Low-Cost Capture

Trace amounts of mercury are found in all coals. During combustion this mercury is vaporized and can be released to the atmosphere. This has been a cause for concern for a number of years, and has resulted in a determination by the EPA to regulate and control these emissions. Present technology does not, however, provide inexpensive ways to capture or remove mercury from flue gases. The mercury that exits the furnace in the oxidized form (HgCl{sub 2}) is known to much more easily captured in existing wet pollution control equipment (e.g., wet FGD for SO{sub 2}), principally due to its high solubility in water. Until recently, however, nobody knew what caused this oxidation, or how to promote it. Recent DOE-funded research in our group, along with work by others, has identified the gas phase mechanism responsible for this oxidation. The scenario is as follows. In the flame the mercury is quantitatively vaporized as elemental mercury. Also, the chlorine in the fuel is released as HCl. The direct reaction Hg+HCl is, however, far too slow to be of practical consequence in oxidation. The high temperature region does supports a small concentration of atomic chlorine due to disassociation of HCl. As the …
Date: March 30, 2003
Creator: Kramlich, John C. & Castiglone, Linda
Object Type: Report
System: The UNT Digital Library
Assessment of CO2 Sequestration and ECBM Potential of U.S. Coalbeds (open access)

Assessment of CO2 Sequestration and ECBM Potential of U.S. Coalbeds

In October, 2000, the U.S. Department of Energy, through contractor Advanced Resources International, launched a multi-year government-industry R&D collaboration called the Coal-Seq project. The Coal-Seq project is investigating the feasibility of CO{sub 2} sequestration in deep, unmineable coalseams, by performing detailed reservoir studies of two enhanced coalbed methane recovery (ECBM) field projects in the San Juan basin. The two sites are the Allison Unit, operated by Burlington Resources, and into which CO{sub 2} is being injected, and the Tiffany Unit, operating by BP America, into which N{sub 2} is being injected (the interest in understanding the N{sub 2}-ECBM process has important implications for CO{sub 2} sequestration via flue-gas injection). The purposes of the field studies are to understand the reservoir mechanisms of CO{sub 2} and N{sub 2} injection into coalseams, demonstrate the practical effectiveness of the ECBM and sequestration processes, an engineering capability to simulate them, and to evaluate sequestration economics. In support of these efforts, laboratory and theoretical studies are also being performed to understand and model multi-component isotherm behavior, and coal permeability changes due to swelling with CO{sub 2} injection. This report describes the results of an important component of the overall project, applying the findings from the …
Date: March 31, 2003
Creator: Reeves, Scott R.
Object Type: Report
System: The UNT Digital Library
Influence of Clastic Dikes on Vertical Migration of Contaminants in the Vadose Zone at Hanford (open access)

Influence of Clastic Dikes on Vertical Migration of Contaminants in the Vadose Zone at Hanford

The purpose of this study was to examine the hypothesis that clastic dikes could form a preferential flow path through the vadose zone to the water table at the Hanford Site. Clastic dikes are subvertical structures that form within sedimentary sequences after deposition, and cut across the original sedimentary layers. They are common throughout the Hanford Site, often occurring in organized polygonal networks. In the initial phase of the project, we analyzed the large-scale geometry of the clastic dikes and developed an algorithm for simulating their spatial distribution. This result will be useful in providing maps of the potential distribution of clastic dikes in areas where they are not exposed at the surface (e.g., where covered by windblown sand or by construction of facilities like tank farms at the surface). In addition to the study of the large scale distribution of the dikes, a major focus of the project was on field, laboratory, and modeling studies of the hydrogeologic al properties of the clastic dikes and the effect that they have on transport of water through the vadose zone. These studies were performed at two field locations at the Hanford Site. We performed an extensive series of field and laboratory …
Date: March 14, 2003
Creator: Murray, Christopher J.; Ward, Anderson L. & Wilson, John L.
Object Type: Report
System: The UNT Digital Library
Feasibility Study of Passive Aerosol Sampler for Bio-Agent Detection (open access)

Feasibility Study of Passive Aerosol Sampler for Bio-Agent Detection

We propose to establish the feasibility of a passive aerosol sampler for bio-agent collection through laboratory experiments and theoretical analysis. The passive sampler, unlike the typical active sampler, does not require pumps and complex fixtures, and thereby allows for large-scale field monitoring not possible with current active samplers. We plan to conduct experiments using model (both biological and non-biological) aerosols generated in an instrumented test chamber and compare the particles collected on various passive samplers to conventional filter samplers, commercial aerosol measuring instruments and to conventional surface swipes. Theoretical analysis will be used to design prototype passive samplers and to compare experimental results with theory. A successful feasibility study will be used to seek outside funding for applications that will greatly enhance current LLNL programs such as NARAC's atmospheric dispersal modeling, NAI's programs in bioagent monitoring in public locations and fixed sampling stations, and EPD's environmental monitoring and decontamination research. In addition, the feasibility study will position us favorably for responding to new calls for proposals by NIH and EPA for large scale environmental studies.
Date: March 5, 2003
Creator: Keating, G. & Bergman, W.
Object Type: Report
System: The UNT Digital Library
Delamination Failure Investigation for Out-Of-Plane Loading in Laminates (open access)

Delamination Failure Investigation for Out-Of-Plane Loading in Laminates

In contrast to failure approaches at the lamina level or the micromechanics level the present work concerns failure characterization at the laminate level. Specifically, attention is given to the ultimate failure characterization for quasi-isotropic laminates. This is in further contrast to the commonly used approaches for initial damage or progressive damage. It is shown that the analytical failure forms decompose into two modes, one for out of plane, delamination type failure and one for in plane, fiber controlled type failure. The work here is mainly given over to the delamination mode of failure. Experimental results are presented for laminates in this mode of failure. These results are then integrated with the analytical forms to give a simple criterion for delamination failure.
Date: March 26, 2003
Creator: Christensen, R M & DeTeresa, S J
Object Type: Article
System: The UNT Digital Library
Updated Volumetric Expansion Factors for K Basin Sludge During Storage (open access)

Updated Volumetric Expansion Factors for K Basin Sludge During Storage

Sludge has accumulated in the K East (KE) and K West (KW) Basins at the Hanford Site. This sludge contains metallic uranium and uranium oxides that will corrode, hydrate, and generate and consume gases during containerized storage. From these corrosion reactions, two sludge expansion mechanisms can be expected: 1) expansion of the volume of the sludge solids from the generation of corrosion oxidation products that occupy more space than the starting-state sludge; and 2) expansion of the bulk sludge volume from the retention of hydrogen gas bubbles. This report provides a review and updated projections of the volumetric expansion occurring due to corrosion and gas retention during the containerized storage of K Basin sludge. New design and safety basis volume expansion values are provided for the following sludge streams: KW Floor, KW North Loadout Pit, KW canister, and fuel piece sludge.
Date: March 14, 2003
Creator: Schmidt, Andrew J. (BATTELLE (PACIFIC NW LAB)) & Delegard, Calvin H. (BATTELLE (PACIFIC NW LAB))
Object Type: Report
System: The UNT Digital Library
Laser Science and Technology Program Annual Report-2002 NIF Programs Directorate (open access)

Laser Science and Technology Program Annual Report-2002 NIF Programs Directorate

The Laser Science and Technology (LS&T) Program's mission is to develop advanced lasers, optics, materials technologies, and applications to solve problems and create new capabilities of importance to the nation and the Laboratory. A top, near-term priority is to provide technical support in the deployment and upgrade of the National Ignition Facility (NIF). Our other program activities synergistically develop technologies that are consistent with the goals of the NIF Directorate and develop state-of-the-art capabilities. The primary objectives of LS&T activities in 2002 have been fourfold--(a) to support deployment of hardware and to enhance laser and optics performance for NIF, (b) to develop high-energy petawatt laser science and technology for the Department of Energy (DOE), (c) to develop advanced solid-state laser systems and optical components for the Department of Defense (DoD), and (d) to invent, develop, and deliver improved concepts and hardware for other government agencies and industry. LS&T activities during 2002 focused on seven major areas: (1) NIF Project-LS&T led major advances in the deployment of NIF Final Optics Assembly (FOA) and the development of 30.1 optics processing and treatment technologies to enhance NIF's operations and performance capabilities. (2) Stockpile Stewardship Program (SSP)-LS&T personnel continued development of ultrashort-pulse lasers and …
Date: March 1, 2003
Creator: Hackel, L. & Chen, H. L.
Object Type: Report
System: The UNT Digital Library
A Systematic Approach for the Evaluation of Technology Opportunities to Enhance the Proliferation Resistance of Civilian Nuclear Energy Systems (open access)

A Systematic Approach for the Evaluation of Technology Opportunities to Enhance the Proliferation Resistance of Civilian Nuclear Energy Systems

Enhancing the proliferation resistance of nuclear energy systems and fuel cycles is an ambitious undertaking. Current systems, dominated by the light water reactor fuel cycle are quite proliferation resistant. However, continued accumulations of plutonium in spent fuel and accumulations of separated plutonium resulting from reprocessing are eroding the proliferation resistance of today's nuclear energy systems. Alternatives to address these issues invariably involve making trade-offs among different proliferation risks and advantages. For example, thorium cycles reduce the quantity and quality of plutonium in spent fuel, but do so at the expense of increased fresh fuel enrichment and/or production of separable U233. Evaluation of these tradeoffs is difficult, as there are serious and significant differences of opinion regarding the relative merits and significance of the various risks of and barriers to proliferation from commercial nuclear power fuel cycles.
Date: March 10, 2003
Creator: Hassberger, J
Object Type: Article
System: The UNT Digital Library
Passive Seismic Monitoring for Rockfall at Yucca Mountain: Concept Tests (open access)

Passive Seismic Monitoring for Rockfall at Yucca Mountain: Concept Tests

For the purpose of proof-testing a system intended to remotely monitor rockfall inside a potential radioactive waste repository at Yucca Mountain, a system of seismic sub-arrays will be deployed and tested on the surface of the mountain. The goal is to identify and locate rockfall events remotely using automated data collecting and processing techniques. We install seismometers on the ground surface, generate seismic energy to simulate rockfall in underground space beneath the array, and interpret the surface response to discriminate and locate the event. Data will be analyzed using matched-field processing, a generalized beam forming method for localizing discrete signals. Software is being developed to facilitate the processing. To date, a three-component sub-array has been installed and successfully tested.
Date: March 3, 2003
Creator: Cheng, J.; Twilley, K.; Murvosh, H.; Tu, Y.; Luke, B.; Yfantis, A. et al.
Object Type: Article
System: The UNT Digital Library
Rates, Polarizations, and Asymmetries in Charmless Vector-Vector B Decays (open access)

Rates, Polarizations, and Asymmetries in Charmless Vector-Vector B Decays

With a sample of approximately 89 million B{bar B} pairs collected with the BABAR detector, they measure branching fractions, determine the degree of longitudinal polarization, and search for direct CP violation in the decays B{sup 0} {yields} {phi}K*{sup 0} and B{sup +} {yields} {phi}K*{sup +}. They perform a search for other charmless vector-vector B decays involving {rho} and K*(892) resonances and observe the decays B{sup +} {yields} {rho}{sup 0} K*{sup +} and B{sup +} {yields} {rho}{sup 0}{rho}{sup +}. The branching fractions are measured to be {Beta}({phi}K*{sup 0}) = (11.1{sub -1.2}{sup +1.3} {+-} 1.1) x 10{sup -6}, {Beta}({phi}K*{sup +}) = (12.1{sub -1.9}{sup +2.1} {+-} 1.5) x 10{sup -6}, {Beta}({rho}{sup 0} K*{sup +}) = (7.7{sub -2.0}{sup +2.1} {+-} 1.4) x 10{sup -6}, and {Beta}({rho}{sup 0}{rho}{sup +}) = (9.9{sub -2.5}{sup +2.6} {+-} 2.5) x 10{sup -6}. The longitudinal polarization fractions are measured to be {Lambda}{sub L}/{Lambda}({phi}K*{sup 0}) = 0.65 {+-} 0.07 {+-} 0.04 and {Lambda}{sub L}/{Lambda}({phi}K*{sup +}) = 0.46 {+-} 0.12 {+-} 0.05. They measure the charge asymmetries: {Alpha}{sub CP}({phi}K*{sup 0}) = +0.04 {+-} 0.12 {+-} 0.02 and {Alpha}{sub CP}({phi}K*{sup +}) = +0.16 {+-} 0.17 {+-} 0.04.
Date: March 11, 2003
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Gaillard, J.-M.; Hicheur, A.; Karyotakis, Y. et al.
Object Type: Article
System: The UNT Digital Library
The LEOS Interpolation Package (open access)

The LEOS Interpolation Package

This report describes the interpolation package in the Livermore Equation of State (LEOS) system. It is an updated and expanded version of report [1], which described the status of the package as of May 1998, and of [2], which described its status as of the August 2001 release of the LEOS access library, and of [3], which described its status as of library version 7.02, released April 2002. This corresponds to library version 7.11, released March 2003. The main change since [3] has been the addition of the monotone bicubic Hermite (bimond) interpolation method. Throughout this report we assume that data has been given for some function f({rho},T) on a rectangular mesh {rho} = {rho}{sub 0}, {rho}{sub 1}, ..., {rho}{sub nr-1}; T = T{sub 0}, T{sub 1}, ..., T{sub nt-1}. Subscripting is from zero to be consistent with the C code. (Although we use this notation throughout, there is nothing in the package that assumes that the independent variables are actually density and temperature.) The data values are f{sub ij} = f({rho}{sub j},T{sub i}). (This subscript order is historical and reflects the notation used in the program.) There are nr x nt data values, (nr-1) x (nt-1) mesh rectangles (boxes). …
Date: March 12, 2003
Creator: Fritsch, F N
Object Type: Report
System: The UNT Digital Library
Design and Performance of Capping Layers for EUV Multilayer Mirrors (open access)

Design and Performance of Capping Layers for EUV Multilayer Mirrors

The reflectance stability of multilayer coatings for extreme ultraviolet lithography (EUVL) in a commercial tool environment is of uttermost importance to ensure continuous exposures with minimum maintenance cost. We have made substantial progress in designing the protective capping layer coatings, understanding their performance and estimating their lifetimes based on accelerated electron beam and EUV exposure studies. Our current capping layer coatings have about 40 times longer lifetimes than Si-capped multilayer optics. Nevertheless, the lifetime of current Ru-capped multilayers is too short to satisfy commercial tool requirements and further improvements are essential.
Date: March 10, 2003
Creator: Bajt, S.; Chapman, H. N.; Nuygen, N.; Alameda, J.; Robinson, J. C.; Malinowski, M. et al.
Object Type: Article
System: The UNT Digital Library
Advanced Petroleum-Based Fuels -- Diesel Emissions Control Project (APBF-DEC) (open access)

Advanced Petroleum-Based Fuels -- Diesel Emissions Control Project (APBF-DEC)

Annual progress report of the Advanced Petroleum-based fuels-Diesel Emissions Control Project. Contains information on 5 test projects to determine the best combinations of low-sulfur diesel fuels, lubricants, diesel engines, and emission control systems to meet projected emissions standards.
Date: March 1, 2003
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Associated Higgs Boson Production With Heavy Quarks. (open access)

Associated Higgs Boson Production With Heavy Quarks.

The production of a Higgs boson in association with a pair of e quarks will play a very important role at both hadron and lepton colliders. We review the status of theoretical predictions and their relevance to Higgs boson studies, with particular emphasis on the recently calculated NLO QCD corrections to the inclusive cross section for p{bar p}, pp {yields} t{bar t}h. We conclude by briefly discussing the case of exclusive b{bar b}h production and the potential of this process in revealing signals of new physics beyond the Standard Model.
Date: March 15, 2003
Creator: Dawson, S.; Orr, L. H.; Reina, L. & Wackeroth, D.
Object Type: Article
System: The UNT Digital Library
Adaptive Optics Applications in Vision Science (open access)

Adaptive Optics Applications in Vision Science

Adaptive optics can be used to correct the aberrations in the human eye caused by imperfections in the cornea and the lens and thereby, improve image quality both looking into and out of the eye. Under the auspices of the NSF Center for Adaptive Optics and the DOE Biomedical Engineering Program, Lawrence Livermore National Laboratory has joined together with leading vision science researchers around the country to develop and test new ophthalmic imaging systems using novel wavefront corrector technologies. Results of preliminary comparative evaluations of these technologies in initial system tests show promise for future clinical utility.
Date: March 17, 2003
Creator: Olivier, S. S.
Object Type: Article
System: The UNT Digital Library
6th Workshop on Fast Ignition of Fusion Targets (open access)

6th Workshop on Fast Ignition of Fusion Targets

None
Date: March 26, 2003
Creator: Key, M H
Object Type: Report
System: The UNT Digital Library