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97-ERD-022 final report: Supernova on Nova
This is the final year of the 3-year LDRD-ERD involving Lasers, D&NT, Physics, and ILSA to develope astrophysics experiments on intense lasers such as the Nova and Gekko lasers. During this 3 year period, we have developed a highly successful experiment probing the hydrodynamics of the explosion phase of core-collapse supernovae, which occurs during the first ~3 hours after core collapse. This was in collaboration with the Univ. of Arizona and CEA/Saclay. We also developed a very successful experiment to probe the hydrodynamics of the later time, young remnant phase, meaning the first ~10-20 years after core collapse. This was in collaboration with the Univ. of Michigan and Univ. of Colorado. Finally, we developed during the final year an exquisite experiment to probe the dynamics of radiative, high Mach number astrophysical jets, in collaboration with the Univ. of Maryland and Osaka Univ. Each experiment has received very high visibility, with a multitude of publications, both in the technical journals (most importantly, the astrophysical journals) and in the popular press. The attached publication list shows 25 papers published or submitted to technical journals, 5 articles appearing in the popular press (including a cover story of Sky and Telescope), and 65 conference …
Date:
March 11, 1999
Creator:
Remington, B. A.
Object Type:
Report
System:
The UNT Digital Library
The 239 Pu(n,2n)238Pu cross section: preliminary calculations
The primary motivation for the present work is to provide theoretical values for the ratio of the partial <sup>239</sup>Pu(n,2nx{gamma})<sup>238</sup>Pu to total <sup>239</sup> Pu(n,2n)<sup>238</sup>Pu cross section for several discrete gamma transitions. Results and conclusions of preliminary calculations from threshold to 20 MeV are presented. Calculations are based on theoretical models with parameters obtained from the literature or from our ad hoc systematics. Optical model cross sections and transmission coefficients were determined using the coupled-channels method. The calculations included a preequilibrium component followed by multiple particle and gamma-ray emissions. Fission competition was included at all stages of de-excitation. Suggestions for further verifications and possible improvements are provided.
Date:
March 12, 1999
Creator:
Chen, H.; Reffo, G.; Ross, M. A. & White, R. M.
Object Type:
Report
System:
The UNT Digital Library
15th Street News (Midwest City, Okla.), Vol. 28, No. 20, Ed. 1 Friday, March 5, 1999
Newspaper from Rose State College in Midwest City, Oklahoma that includes national, local, and campus news along with advertising.
Date:
March 5, 1999
Creator:
Pace, Joshua
Object Type:
Newspaper
System:
The Gateway to Oklahoma History
15th Street News (Midwest City, Okla.), Vol. 28, No. 21, Ed. 1 Friday, March 12, 1999
Newspaper from Rose State College in Midwest City, Oklahoma that includes national, local, and campus news along with advertising.
Date:
March 12, 1999
Creator:
Pace, Joshua
Object Type:
Newspaper
System:
The Gateway to Oklahoma History
15th Street News (Midwest City, Okla.), Vol. 28, No. 22, Ed. 1 Friday, March 26, 1999
Newspaper from Rose State College in Midwest City, Oklahoma that includes national, local, and campus news along with advertising.
Date:
March 26, 1999
Creator:
Pace, Joshua
Object Type:
Newspaper
System:
The Gateway to Oklahoma History
1998 Tier two emergency and hazardous chemical inventory - emergency planning and community right-to-know act section 312
The Hanford Site covers approximately 1,450 square kilometers (560 square miles) of land that is owned by the U.S, Government and managed by the U.S. Department of Energy, Richland Operations Office (DOE-RL). The Hanford Site is located northwest of the city of Richland, Washington. The city of Richland adjoins the southeastern portion of the Hanford Site boundary and is the nearest population center. Activities on the Hanford Site are centralized in numerically designated areas. The 100 Areas, located along the Columbia River, contain deactivated reactors. The processing units are in the 200 Areas, which are on a plateau approximately 11 kilometers (7 miles) from the Columbia River. The 300 Area, located adjacent to and north of Richland, contains research and development laboratories. The 400 Area, 8 kilometers (5 miles) northwest of the 300 Area, contains the Fast Flux Test Facility previously used for testing liquid metal reactor systems. Adjacent to the north of Richland, the 1100 Area contains offices associated with administration, maintenance, transportation, and materials procurement and distribution. The 600 Area covers all locations not specifically given an area designation. This Tier Two Emergency and Hazardous Chemical Inventory report contains information pertaining to hazardous chemicals managed by DOE-RL and …
Date:
March 2, 1999
Creator:
ZALOUDEK, D.E.
Object Type:
Report
System:
The UNT Digital Library
1999 Report on Hanford Site land disposal restriction for mixed waste
This report was submitted to meet the requirements of Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement) Milestone M-26-011. This milestone requires the preparation of an annual report that covers characterization, treatment, storage, minimization, and other aspects of managing land-disposal-restricted mixed waste at the Hanford Facility.
Date:
March 25, 1999
Creator:
Black, D. G.
Object Type:
Report
System:
The UNT Digital Library
1999 Small Agency Management Control Audit
Report of the Texas State Auditor's Office related to the identification and evaluation of management controls at seven small agencies, specifically controls that are most critical in supporting the accomplishment of legislative mandates.
Date:
March 1999
Creator:
Texas. Office of the State Auditor.
Object Type:
Report
System:
The Portal to Texas History
2D Numerical Simulation of the Resistive Reconnection Layer
In this paper we present a two-dimensional numerical simulation of a reconnection current layer in incompressible resistive magnetohydrodynamics with uniform resistivity in the limit of very large Lundquist numbers. We use realistic boundary conditions derived consistently from the outside magnetic field, and we also take into account the effect of the back pressure from flow into the separatrix region. We find that within a few Alfvén times the system reaches a steady state consistent with the Sweet-Parker model, even if the initial state is Petschek-like.
Date:
March 1, 1999
Creator:
Kulsrud, R. M. & Uzdensky, D. A.
Object Type:
Report
System:
The UNT Digital Library
Ab-initio based calculations of vacancy formation and clustering energies including lattice relaxation in Fe{sub 3}Al
Vacancy formation and clustering significantly affect structural properties of transition-metal aluminides. Ab-initio quantum mechanical total-energy calculations using a full-potential linear combination of muffin-tin orbitals (LMTO) technique provide a convenient method of studying relevant characteristics such as changes in density of states, and charge redistribution around defects. Augmented with Hellmann-Feymann forces, LMTO allows calculations of relaxation geometries and relaxation energies. The authors have performed such calculations for vacancies and antisite substitutional point defects in Fe{sub 3}Al with DO{sub 3} crystallographic structure. There are two limiting factors complicating calculations of defect formation energies directly from ab-initio calculations. The first is that a single defect, due to the lattice periodicity necessitated by the use of ab-initio total energy techniques, cannot be considered as an isolated defect, even in the maximum computable simulation cell. Unlike previous calculations, which did not find a dependency on the size of the simulation cell, the calculations have shown a significant difference in results for 32- and 16- atom cells. This difference provides information about vacancy clustering since it can be explained by a relatively small attractive interaction energy {approximately} 0.2 eV between two vacancies located in adjacent simulation cells and separated by the lattice constant distance (5.52 {angstrom}). …
Date:
March 1, 1999
Creator:
Muratov, L. S.; Cooper, B. R. & Wills, J. M.
Object Type:
Article
System:
The UNT Digital Library
An AC magnetohydrodynamic micropump: towards a true integrated microfluidic system
An AC Magnetohydrodynamic (MHD) micropump has been demonstrated in which the Lorentz force is used to propel an electrolytic solution along a microchannel etched in silicon. This micropump has no moving parts, produces a continuous (not pulsatile) flow, and is compatible with solutions containing biological specimens. micropump, using the Lorentz force as the pumping mechanism for biological analysis. The AC Magnetohydrodynamic (MHD) micropump investigated produces a continuous flow and allows for complex microchannel design.
Date:
March 1, 1999
Creator:
Lee, A. P.; Lemoff, A. V.; McConaghy, C. F. & Miles, R. R.
Object Type:
Article
System:
The UNT Digital Library
Accelerated Aging of Polymer Composite Bridge Materials
Accelerated aging research on samples of composite material and candidate ultraviolet (UV) protective coatings is determining the effects of six environmental factors on material durability. Candidate fastener materials are being evaluated to determine corrosion rates and crevice corrosion effects at load-bearing joints. This work supports field testing of a 30-ft long, 18-ft wide polymer matrix composite (PMC) bridge at the Idaho National Engineering and Environmental Laboratory (INEEL). Durability results and sensor data from tests with live loads provide information required for determining the cost/benefit measures to use in life-cycle planning, determining a maintenance strategy, establishing applicable inspection techniques, and establishing guidelines, standards, and acceptance criteria for PMC bridges for use in the transportation infrastructure.
Date:
March 1, 1999
Creator:
Rodriguez, J. G.; Blackwood, L. G.; Torres, L. L.; Carlson, N. M. & Yoder, T. S.
Object Type:
Article
System:
The UNT Digital Library
Accelerated Aging of Polymer Composite Bridge Materials
Accelerated aging research on samples of composite material and candidate ultraviolet (UV) protective coatings is determining the effects of six environmental factors on material durability. Candidate fastener materials are being evaluated to determine corrosion rates and crevice corrosion effects at load-bearing joints. This work supports field testing of a 30-ft long, 18-ft wide polymer matrix composite (PMC) bridge at the Idaho National Engineering and Environmental Laboratory (INEEL). Durability results and sensor data from tests with live loads provide information required for determining the cost/benefit measures to use in life-cycle planning, determining a maintenance strategy, establishing applicable inspection techniques, and establishing guidelines, standards, and acceptance criteria for PMC bridges for use in the transportation infrastructure.
Date:
March 1, 1999
Creator:
Carlson, Nancy Margaret; Blackwood, Larry Gene; Torres, Lucinda Laine; Rodriguez, Julio Gallardo & Yoder, Timothy Scott
Object Type:
Article
System:
The UNT Digital Library
Acceleration of Polarized Protons to High Energy.
High energy polarized beam collisions will open up the unique physics opportunities of studying spin effects in hard processes. However, the acceleration of polarized beams in circular accelerators is complicated by the numerous depolarizing spin resonances. Using a partial Siberian Snake and a rf dipole that ensure stable adiabatic spin motion during acceleration has made it possible to accelerate polarized protons to 25 GeV at the Brookhaven AGS. Full Siberian Snakes and polarimeters are being developed for RHIC to make the acceleration of polarized protons to 250 GeV possible. A similar scheme is being studied for the 800 GeV HERA proton accelerator.
Date:
March 29, 1999
Creator:
Roser, T.
Object Type:
Article
System:
The UNT Digital Library
Acceleration Stages for a Muon Collider.
None
Date:
March 29, 1999
Creator:
Berg, J. S.
Object Type:
Article
System:
The UNT Digital Library
Accident response -- X-ray to virtual environment
The Engineering Sciences and Applications (ESA) Division of Los Alamos National Laboratory (LANL) has been working to develop a process to extract topographical information from digital x-ray data for modeling in a Computer Aided Design (CAD) environment and translation into a virtual environment. The application for this process is the evolution of a field deployable tool for use by the Accident Response Group (ARG) at the Laboratory. The authors have used both CT Scan and radiography data in their process development. The data is translated into a format recognizable by Pro/ENGINEER{trademark} and then into a virtual environment that can be operated on by dVISE{trademark}. They have successfully taken both CT Scan and radiograph data of single components and created solid and virtual environment models for interrogation.
Date:
March 1, 1999
Creator:
Hefele, J.; Stupin, D.; Kelley, T.; Sheats, M. & Tsai, C.
Object Type:
Article
System:
The UNT Digital Library
An Accuracy Evaluation for the Madejski Splat-Quench Solidification Model
Development of methods to spray form materials by precisely controlled deposition of droplets can result in new manufacturing processes which offer improved metallurgical performance and reduced production costs. These processes require a more detailed knowledge of the fluid mechanics, heat transfer and solidification that occur during droplet spreading. Previous work using computer simulations of this process have been difficult to implement and have required long running times. This paper examines the use of an alternative, simplified, method developed by Madjeski for solving for the problem of droplet spreading and solidification. These simplifications reduce the overall splat spreading and solidification problem to a closed-form differential equation. This differential equation is then solved under various conditions as reported from recent publications of experimental and numerical results of drop analysis. The results from the model are compared in terms of maximum spl at diameter, minimum splat thickness, and time for the droplet spreading to reach 95% of the maximum diameter. The results indicate that the accuracy of the model can be improved by accounting for energy losses in the initial rate of droplet spreading. The model results show that the predictions of experimental results are improved to within 30% over a wide range …
Date:
March 1, 1999
Creator:
Aceves, S. M.; Sahai, V. & Shapiro, A. B.
Object Type:
Article
System:
The UNT Digital Library
Achieving Finite Element Mesh Quality via Optimization of the Jacobian Matrix Norm and Associated Quantities, Part II - A Framework for Volume Mesh Optimization and the Condition Number of the Jacobian Matrix
Three-dimensional unstructured tetrahedral and hexahedral finite element mesh optimization is studied from a theoretical perspective and by computer experiments to determine what objective functions are most effective in attaining valid, high quality meshes. The approach uses matrices and matrix norms to extend the work in Part I to build suitable 3D objective functions. Because certain matrix norm identities which hold for 2 x 2 matrices do not hold for 3 x 3 matrices. significant differences arise between surface and volume mesh optimization objective functions. It is shown, for example, that the equivalence in two-dimensions of the Smoothness and Condition Number of the Jacobian matrix objective functions does not extend to three dimensions and further. that the equivalence of the Oddy and Condition Number of the Metric Tensor objective functions in two-dimensions also fails to extend to three-dimensions. Matrix norm identities are used to systematically construct dimensionally homogeneous groups of objective functions. The concept of an ideal minimizing matrix is introduced for both hexahedral and tetrahedral elements. Non-dimensional objective functions having barriers are emphasized as the most logical choice for mesh optimization. The performance of a number of objective functions in improving mesh quality was assessed on a suite of realistic …
Date:
March 26, 1999
Creator:
Knupp, P.M.
Object Type:
Article
System:
The UNT Digital Library
Acoustic and Seismic Modalities for Unattended Ground Sensors
In this paper, we have presented the relative advantages and complementary aspects of acoustic and seismic ground sensors. A detailed description of both acoustic and seismic ground sensing methods has been provided. Acoustic and seismic phenomenology including source mechanisms, propagation paths, attenuation, and sensing have been discussed in detail. The effects of seismo-acoustic and acousto-seismic interactions as well as recommendations for minimizing seismic/acoustic cross talk have been highlighted. We have shown representative acoustic and seismic ground sensor data to illustrate the advantages and complementary aspects of the two modalities. The data illustrate that seismic transducers often respond to acoustic excitation through acousto-seismic coupling. Based on these results, we discussed the implications of this phenomenology on the detection, identification, and localization objectives of unattended ground sensors. We have concluded with a methodology for selecting the preferred modality (acoustic and/or seismic) for a particular application.
Date:
March 31, 1999
Creator:
Elbring, G.J.; Ladd, M.D.; McDonald, T.S. & Sleefe, G.E.
Object Type:
Article
System:
The UNT Digital Library
Acoustic detection of Immiscible Liquids in Sand
Laboratory cross-well P-wave transmission at 90 kHz was measured in a 61 cm diameter by 76 cm tall water-saturated sand pack, before and after introducing a non-aqueous phase organic liquid (NAPL) (n-dodecane). In one experiment NAPL was introduced to form a lens trapped by a low permeability layer; a second experiment considered NAPL residual trapped behind the front of flowing NAPL. The NAPL caused significant changes in the travel time and amplitude of first arrivals, as well as the generation of diffracted waves arriving after the direct wave. The spatial variations in NAPL saturation obtained from excavation at the end of the experiment correlated well with the observed variations in the P-wave amplitudes and travel times. NAPL residual saturation changes from NAPL flow channels of 3 to 4% were detectable and the 40 to 80% NAPL saturation in the NAPL lens was clearly visible at acoustic frequencies. The results of these experiments demonstrate that small NAPL saturations may be more easily detected with amplitude rather than travel time data, but that the relationships between the amplitude changes and NAPL saturation maybe more complex than those for velocity.
Date:
March 1, 1999
Creator:
Geller, Jil T.; Kowalsky, Michael B.; Seifert, Patricia K. & Nihei, Kurt T.
Object Type:
Article
System:
The UNT Digital Library
Adaptive Optics and NICMOS Uniqueness Space
As part of the HST Second Decade Study a subgroup consisting of Claire Max, James Beletic, Donald McCarthy, and Keith Noll has analyzed the expected performance of near-infra-red adaptive optics systems on the new generation of 8-10 meter ground-based telescopes, for comparison with HST. In addition the subgroup has polled the adaptive optics community regarding expected adaptive optics performance over the coming five years. Responses have been received from representatives of most of the major telescopes: Gemini, VLT, Keck, LBT, and the MMT, as well as of several operational 3-4 meter telescope AO systems. The present document outlines the conclusions to date, with emphasis on aspects relevant to the NICMOS cryocooler Independent Science Review. In general the near-infra-red capabilities of the new ground-based adaptive optics systems will be complementary to the capabilities of NICMOS. For example NICMOS will have greater H-band sensitivity, broader wavelength coverage, and higher point-spread-function stability, whereas ground-based adaptive optics instruments will have higher spatial and spectral resolution. Section 2 of this report outlines the operational constraints faced by the first generation of adaptive optics (AO) systems on new 8-10 meter telescopes. Section 3 describes the areas of relative strength of near-infra-red observing from the ground via …
Date:
March 22, 1999
Creator:
Max, C.
Object Type:
Report
System:
The UNT Digital Library
Adiabatic Excitation of Longitudinal Bunch Shape Oscillations.
By modulating the rf voltage at near twice the synchrotron frequency we are able to modulate the longitudinal bunch shape. We show experimentally that this can be done while preserving the longitudinal emittance when the rf voltage modulation is turned on adiabatically. Experimental measurements will be presented along with theoretical predictions.
Date:
March 29, 1999
Creator:
Bai, M.; Brown, K.; Fischer, W.; Roser, T.; Smith, K.; Tsoupas, N. et al.
Object Type:
Article
System:
The UNT Digital Library
Adult Education and Family Literacy Act, Title II of the Workforce Investment Act of 1998, P.L. 105-220
This report is concerned with the federal adult education and literacy programs authorized by the Adult Education and Family Literacy Act (AEFLA). The report covers funding and spending in the program and how it is budgeted. The report also discusses the consequences of the AEFLA repealing the Adult Education Act (AEA) but continuing some of the programs that were under it.
Date:
March 25, 1999
Creator:
Irwin, Paul M.
Object Type:
Report
System:
The UNT Digital Library
Advanced Combustor Design Concept to Control NOx and Air Toxics: Final Technical Report
Direct coal combustion needs to be a primary energy source for the electric utility industry and for heavy manufacturing during the next several decades because of the availability and economic advantage of coal relative to other fuels and because of the time required to produce major market penetration in the energy field. However, the major obstacle to coal utilization is a set of ever-tightening environmental regulations at both the federal and local level. It is, therefore, critical that fundamental research be conducted to support the development of low-emission, high-efficiency pulverized coal power systems. The objective of this program was to develop fundamental understanding regarding the impact of fuel and combustion changes on NOx formation, carbon burnout and air toxic emissions from pulverized coal (pc) combustion. During pc combustion, nitrogen in the coal can be oxidized to form nitrogen oxides (NO{sub x}). The 1990 Clean Air Act Amendments established much stricter NO{sub x} emissions limits for new and existing coal-fired plants, so there has been renewed interest in the processes by which NO{sub x} forms in pc flames. One of the least understood aspects of NO{sub x} formation from pc combustion is the process by which char-N (nitrogen remaining in the …
Date:
March 29, 1999
Creator:
Eddings, Eric G.; Pershing, David W.; Molina, Alejandro; Sarofim, Adel F.; Spinti, Jennifer P. & Veranth, John
Object Type:
Report
System:
The UNT Digital Library