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Duals for SU(N) SUSY Gauge Theories with an Antisymmetric Tensor: Five Easy Flavors (open access)

Duals for SU(N) SUSY Gauge Theories with an Antisymmetric Tensor: Five Easy Flavors

I consider N = 1 supersymmetric SU(N{sub c}) gauge theories with matter fields consisting of one antisymmetric representation, five flavors, and enough antifundamental representations to cancel the gauge anomaly. Previous analyses are extended to the case of even N{sub c} with no superpotential. Using holomorphy I show that the theory has an interacting infrared fixed point for sufficiently large N{sub c}. These theories are interesting due to the fact that in going from five to four flavors the theory goes from a non-trivial infrared fixed point to confinement, in contradistinction to SUSY QCD, but in analogy to the behavior expected in non-SUSY QCD.
Date: December 16, 1997
Creator: Terning, John
System: The UNT Digital Library
Requirements of the Proton Beam Accelerator for an Accelerator-Driven Reactor. (open access)

Requirements of the Proton Beam Accelerator for an Accelerator-Driven Reactor.

None
Date: November 16, 1997
Creator: Takahashi, H.; Zhao, Y.; An, Y. & Yamazaki, Y.
System: The UNT Digital Library
The characterization and testing of candidate immobilization forms for the disposal of plutonium. (open access)

The characterization and testing of candidate immobilization forms for the disposal of plutonium.

Candidate immobilization forms for the disposal of surplus weapons-useable are being tested and characterized. The goal of the testing program was to provide sufficient data that, by August 1997, an informed selection of a single immobilization form could be made so that the form development and production R and D could be more narrowly focused. Two forms have been under consideration for the past two years: glass and ceramic. In August, 1997, the Department of Energy (DOE) selected ceramic for plutonium disposition, halting further work on the glass material. In this paper, we will briefly describe these two waste forms, then describe our characterization techniques and testing methods. The analytical methods used to characterize altered and unaltered samples are the same. A full suite of microscopic techniques is used. Techniques used include optical, scanning electron, and transmission electron microscopies. For both candidate immobilization forms, the analyses are used to characterize the material for the presence of crystalline phases and amorphous material. Crystalline materials, either in the untested immobilization form or in the alteration products from testing, are characterized with respect to morphology, crystal structure, and composition. The goal of these analyses is to provide data on critical issues such as …
Date: December 16, 1997
Creator: Bakel, A. J.; Buck, E. C.; Chamberlain, D. B.; Ebbinghaus, B. B.; Fortner, J. A.; Marra, J. C. et al.
System: The UNT Digital Library
A modeling study of perched water phenomena in the vadose zone (open access)

A modeling study of perched water phenomena in the vadose zone

The presence of perched water bodies in the vicinity of the potential repository at Yucca Mountain has many implications, and however, it may provide insight into moisture movement, flow pathways, or surface infiltration history of the mountain. The first implication is that percolation flux does not travel vertically through the unsaturated zone to the water table, but has been trapped, blocked or diverted laterally. As a result, non-uniform recharge rates are expected at the water table. Another concern is that perched zones may divert water around low-permeability zeolitic lenses underlying the potential repository horizon. By-passing of these units, which are thought to have substantial capacity to retard radionuclide transport, could have important implications for the capability of the geologic system to mitigate radionuclide releases to the environment. We have conducted a series of 3-D modeling simulations to investigate the perched water occurrences at the Yucca Mountain site, using a numerical code and available perched water data from six boreholes. A spatially varying surface infiltration map (Flint et al., 1996) is used to describe areally distributed net infiltration at the model land surface. Perched water data observed in the field were used to calibrate the model in terms of matrix and …
Date: December 16, 1997
Creator: Wu, Y.-S.; Ritchey, A. C. & Bodvarsson, G. S.
System: The UNT Digital Library
Diamond radiation detectors II. CVD diamond development for radiation detectors (open access)

Diamond radiation detectors II. CVD diamond development for radiation detectors

Interest in radiation detectors has supplied some of the impetus for improving the electronic properties of CVD diamond. In the present discussion, we will restrict our attention to polycrystalhne CVD material. We will focus on the evolution of these materials over the past decade and the correlation of detector performance with other properties of the material.
Date: May 16, 1997
Creator: Kania, D.R.
System: The UNT Digital Library
Nonlinear Rayleigh-Taylor Instability Experiments in Nova (open access)

Nonlinear Rayleigh-Taylor Instability Experiments in Nova

We examined the progression of the Rayleigh-Taylor (RT) instability from an initial multimode perturbation. The RT experiments focused on the transition from the linear to non-linear regimes for perturbation growth at an embedded, or classical, interface. The multimode experiments have attempted to observe the process of bubble competition wherein neighboring structures either continue to rise or are washed downstream in the flow depending upon; their relative size. This competition is predicted to result in an inverse cascade at late times where progressively larger structures will begin to dominate the flow. Experiments to date have shown evidence of coupled modes arising, but have not yet accelerated the interface long enough to produce the several generations of coupling required for a true inverse cascade.
Date: June 16, 1997
Creator: Budil, K. S.; Remington, B. A.; Weber, S. V.; Perry, T. S. & Peyser, T. A.
System: The UNT Digital Library
Disposition of uranium-233 (open access)

Disposition of uranium-233

The US is developing a strategy for the disposition of surplus weapons-usable uranium-233 ({sup 233}U). The strategy (1) identifies the requirements for the disposition of surplus {sup 233}U; (2) identifies potential disposition options, including key issues to be resolved with each option; and (3) defines a road map that identifies future key decisions and actions. The disposition of weapons-usable fissile materials is part of a US international arms-control program for reduction of the number of nuclear weapons and the quantities of nuclear-weapons-usable materials worldwide. The disposition options ultimately lead to waste forms requiring some type of geological disposal. Major options are described herein.
Date: October 16, 1997
Creator: Tousley, D.R.; Forsberg, C.W. & Krichinsky, A.M.
System: The UNT Digital Library
New prototype equation of state data library (open access)

New prototype equation of state data library

Equation of State (EOS) data is a necessary requirement for the simulation of many dynamic processes, including shock wave propagation, high velocity impact, laser-matter interaction, laser medicine, x-ray deposition and planetary and stellar interior evolution. Realistic simulations require high accuracy and smoothness in the EOS. In addition, some processes require independent ionic, electronic and radiation physics. In order to meet these needs, we have implemented a new EOS data library that is platform independent, hierarchically structured and easily extensible for future development. We have just begun our user testing phase and are considering future improvements.
Date: July 16, 1997
Creator: Corey, E. M. & Young, D. A.
System: The UNT Digital Library
Measurement of RT amplitudes and wavelengths of laser driven plates (open access)

Measurement of RT amplitudes and wavelengths of laser driven plates

A laser drive plate, that is a dense solid plate drive by a laser heated, lower density plasma, is inherently Raleigh-Taylor (R-T) unstable, We have previously indicated that observed surface perturbation on the plate are probably R-T instabilities, initiated by the mode structure of the driving laser beam. Using a semi- transparent impact target viewed with a polarized Epi-Illuminated Confocal Streak Microscope, has allowed us to measure the amplitude and growth of the instability.
Date: October 16, 1997
Creator: Frank, A.M. & Gillespie, C.H.
System: The UNT Digital Library
Emerging patterns in cross-sector partnerships national lab partnerships: what works and what doesn`t (open access)

Emerging patterns in cross-sector partnerships national lab partnerships: what works and what doesn`t

All elements of the research triad in this country - universities, federal laboratories, and industrial labs - have spent a good part of the last decade in a very changeable and changing environment. In the area of partnerships with industry there have been a lot of experiments, such as the Advanced Technology Program (ATP), the Technology Reinvestment Program (TRP), and the Department of Energy`s (DOE) analog, the Technology Transfer Initiative (TM). We now have, at least in principle, gained enough experience with cross-sector partnerships to make some observations on what works and what doesn`t. My judgments are preliminary and driven by the idiosyncrasies of my own lab. I think the general themes at Livermore are reflected in other DOE national security labs and, at least to some extent, in other federal labs. Although we share some features in common with universities and industrial labs, I think the nature of our funding sources, and the way in which we are affected by global political factors such as the Cold War, pose a somewhat special set of circumstances for our institutions.
Date: June 16, 1997
Creator: Tarter, C.B.
System: The UNT Digital Library
Jet fragmentation properties at the Tevatron (open access)

Jet fragmentation properties at the Tevatron

Preliminary CDF results on inclusive momentum distributions of charged particles in high transverse momentum jets produced in {anti p}p collisions at {radical}s=1.8 TeV at the Tevatron are presented and compared with QCD predictions based on the Modified Leading Log Approximation.
Date: May 16, 1997
Creator: Goulianos, K.
System: The UNT Digital Library
Systematic approach to analyzing and reducing aerodynamic drag of heavy vehicles (open access)

Systematic approach to analyzing and reducing aerodynamic drag of heavy vehicles

This paper presents an approach for reducing aerodynamic drag of heavy vehicles by systematically analyzing trailer components using existing computational tools and moving on to the analyses of integrated tractor-trailers using advanced computational tools. Experimental verification and validation are also an important part of this approach. The project is currently in the development phase while we are in the process of constructing a Multi-Year Program Plan. Projects I and 2 as described in this paper are the anticipated project direction. Also included are results from past and current related activities by the project participants which demonstrate the analysis approach.
Date: September 16, 1997
Creator: McCallen, R.; Browand, F.; Leonard, A. & Rutledge, W.
System: The UNT Digital Library
Processing of Oak Ridge B&C pond sludge surrogate in the transportable vitrification system (open access)

Processing of Oak Ridge B&C pond sludge surrogate in the transportable vitrification system

The Transportable Vitrification System (TVS) developed at the Savannah River Site is designed to process low-level and mixed radioactive wastes into a stable glass product. The TVS consists of a feed preparation and delivery system, a joule-heated melter, and an offgas treatment system. Surrogate Oak Ridge Reservation (ORR) B&C pond sludge was treated in a demonstration of the TVS system at Clemson University and at ORR. After initial tests with soda-lime-silica (SLS) feed, three melter volumes of glass were produced from the surrogate feed. A forthcoming report will describe glass characterization; and melter feeding, operation, and glass pouring. Melter operations described will include slurry characterization and feeding, factors affecting feed melt rates, glass pouring and pour rate constraints, and melter operating temperatures. Residence time modeling of the melter will also be discussed. Characterization of glass; including composition, predicted liquidity and viscosity, Toxic Characteristic Leaching Procedure (TCLP), and devitrification will be covered. Devitrification was a concern in glass container tests and was found to be mostly dependent on the cooling rate. Crucible tests indicated that melter shutdown with glass containing Fe and Li was also a devitrification concern, so the melter was flushed with SLS glass before cooldown.
Date: April 16, 1997
Creator: Zamecnik, J. R.; Young, S. R.; Peeler, D. K. & Smith, M. E.
System: The UNT Digital Library
Requalification of the 235-F Metallograph Facility gloveboxes for use in the 773-A Pre-Processing/Re-Processing Laboratory and plutonium ``Can in Can`` demonstrations (open access)

Requalification of the 235-F Metallograph Facility gloveboxes for use in the 773-A Pre-Processing/Re-Processing Laboratory and plutonium ``Can in Can`` demonstrations

The proposed use for these gloveboxes are: (1) to utilize the Pu metal glovebox system for the primary containment associated with the Pre-Processing/Re-Processing Laboratory for obtaining radioactive glass compound viscometer analysis, and (2) to utilize the Pu oxide glovebox system for primary containment associated with the Pu Can in Can Demonstration for proof of principle testing specific to long term Pu immobilization and storage technology. This report presents objective evidence that supports the engineering judgment indicating the existing gloveboxes can be requalified for the proposed uses indicated above. SRS has the ability to duplicate the test parameters, with site forces, that will meet or exceed the identical acceptance criteria established to qualify the existing gloveboxes. The qualification effort will be a documented procedure using the leak test criteria characteristic of the original glovebox purchase. Two equivalent tests will be performed, one for post modification leak test acceptance and one for post installation leak test acceptance. Assurance of this approach is substantiated by thorough reviews of glovebox, leak test and weld standard guidance documents, as well as review of historical Project 3253 design and vendor information specific to the existing gloveboxes. Reuse of these gloveboxes will eliminate the need for competitive …
Date: April 16, 1997
Creator: Hinds, S. & Hidlay, J.
System: The UNT Digital Library
Requalification of the 235-F Metallograph Facility gloveboxes for use in the 773-A plutonium immobilization demonstration (open access)

Requalification of the 235-F Metallograph Facility gloveboxes for use in the 773-A plutonium immobilization demonstration

A concern has been identified regarding the viability of redesigning and requalifying existing glovebox lines for use as glovebox lines integral to future mission activities in the 773-A laboratory building at the Savannah River Site (SRS). The Bechtel Savannah River Inc. (BSRI) design engineering team has been requested to perform an evaluation which would investigate the reuse of these existing gloveboxes versus the procurement of completely new glovebox systems. The existing glovebox lines were manufactured for the Plutonium (Pu) Metallograph Facility, Project 3253, located in building 235-F at SRS. These gloveboxes were designed as independent, fully functional Pu `metal` and Pu `oxide` processing glovebox systems for this facility. These gloveboxes, although fully installed, have never processed radioactive material. The proposed use for these gloveboxes are: (1) to utilize the Pu `metal` glovebox system for the primary containment associated with the Pre-Processing/Re-Processing Laboratory for obtaining radioactive glass compound viscometer analysis and (2) to utilize the Pu `oxide` glovebox system for primary containment associated with the Pu `Can in Can` Demonstration for proof of principle testing specific to long term Pu immobilization and storage technology. This report presents objective evidence that supports the engineering judgment indicating the existing gloveboxes can be requalified …
Date: October 16, 1997
Creator: Hinds, S.S & Hidlay, J.
System: The UNT Digital Library
Phototransformation of Polycyclic Aromatic Hydrocarbons (PAHs) on a Non-Semi Conductive Surface Such as Silica (open access)

Phototransformation of Polycyclic Aromatic Hydrocarbons (PAHs) on a Non-Semi Conductive Surface Such as Silica

Polycyclic aromatic hydrocarbons (PAH), by products of fossil fuel production and consumption, constitute a large class of environmental pollutants. These toxic and sometimes carcinogenic compounds are also found in coal tar and fly ash. When released into the air, they can be sorbed onto particulates present in the atmosphere where they find their way into soil and ground water upon being washed by rain. During their residence time in the environment, PAHs will be exposed to solar radiation and may undergo phototransformation to other products. Thus, light induced photodegradation of PM`s at the solid/air interfaces can play a significant role in their depletion. Light-induced processes have been claimed to enhance transformation of these PM`s in the environment. However, detailed studies on the nature and identities of photoproducts formed during the transformation of these compounds on solid surfaces is scarce. Since insulators such as silica, alumina,silicoaluminates and calcium carbonate are believed to constitute up 20-30% of inorganic particulates present in the atmosphere, they serve as environmentally relevant model surfaces to study the photophysical and photochemical behavior of PM`s. Although photochemistry of organic compounds adsorbed on solid surfaces has received much attention in recent years, the specific properties of the interface which …
Date: September 16, 1997
Creator: Dabestani, R., Sigman, M.E.
System: The UNT Digital Library
Critical parameters for electron beam curing of cationic epoxies and property comparison of electron beam cured cationic epoxies versus thermal cured resins and composites (open access)

Critical parameters for electron beam curing of cationic epoxies and property comparison of electron beam cured cationic epoxies versus thermal cured resins and composites

Electron beam curing of composites is a nonthermal, nonautoclave curing process offering the following advantages compared to conventional thermal curing: substantially reduced manufacturing costs and curing times; improvements in part quality and performance; reduced environmental and health concerns; and improvements in material handling. In 1994 a Cooperative Research and Development Agreement (CRADA), sponsored by the Department of Energy Defense Programs and 10 industrial partners, was established to advance electron beam curing of composites. The CRADA has successfully developed hundreds of new toughened and untoughened resins, offering unlimited formulation and processing flexibility. Several patent applications have been filed for this work. Composites made from these easily processable, low shrinkage material match the performance of thermal cured composites and exhibit: low void contents comparable to autoclave cured composites (less than 1%); superb low water absorption values in the same range as cyanate esters (less than 1%); glass transition temperatures rivaling those of polyimides (greater than 390 C); mechanical properties comparable to high performance, autoclave cured composites; and excellent property retention after cryogenic and thermal cycling. These materials have been used to manufacture many composite parts using various fabrication processes including hand lay-up, tow placement, filament winding, resin transfer molding and vacuum assisted …
Date: January 16, 1997
Creator: Janke, C. J.; Norris, R. E.; Yarborough, K.; Havens, S. J. & Lopata, V. J.
System: The UNT Digital Library
Data warehousing, metadata, and the World Wide Web (open access)

Data warehousing, metadata, and the World Wide Web

The connection between data warehousing and the metadata. used to catalog and locate warehouse data is obvious, but what is the connection between data warehousing, metadata, and the World Wide Web (WWW)? Specifically, the WWW can be used to allow users to search metadata (data about the data) and retrieve data from a warehouse database. In addition, the Internet/Intranet can be used to manage the metadata in archive databases and to streamline the database administration functions of a large archive center. The Oak Ridge National Laboratory`s (ORNL`s) Distributed Active Archive Center (DAAC) is a data archive and distribution center for the National Air and Space Administration`s (NASA`s) Earth Observing System Data and Information System (EOSDIS); the ORNL DAAC provides access to tabular and imagery datasets used in ecological and environmental research. To support this effort, we have taken advantage of the rather unique and user-friendly features of the WWW to (1) allow users to search for and download the data we archive and (2) provide DAAC developers with effective metadata and data management tools. In particular, the ORNL DAAC has developed the Biogeochemical Information Ordering Management Environment (BIOME), a WWW search-and-order system, as well as a WWW-based database administrator`s (DBA`s) …
Date: April 16, 1997
Creator: Yow, T.G.; Smith, A.W. & Daugherty, P.F.
System: The UNT Digital Library
Improving spanning trees by upgrading nodes (open access)

Improving spanning trees by upgrading nodes

We study budget constrained optimal network upgrading problems. Such problems aim at finding optimal strategies for improving a network under some cost measure subject to certain budget constraints. A general problem in this setting is the following. We are given an edge weighted graph G = (V, E) where nodes represent processors and edges represent bidirectional communication links. The processor at a node v {element_of} V can be upgraded at a cost of c(v). Such an upgrade reduces the delay of each link emanating from v. The goal is to find a minimum cost set of nodes to be upgraded so that the resulting network has the best performance with respect to some measure. We consider the problem under two measures, namely, the weight of a minimum spanning tree and the bottleneck weight of a minimum bottleneck spanning tree. We present approximation and hardness results for the problem. Our results are tight to within constant factors. We also show that these approximation algorithms can be used to construct good approximation algorithms for the dual versions of the problems where there is a budget constraint on the upgrading cost and the objectives are minimum weight spanning tree and minimum bottleneck weight …
Date: January 16, 1997
Creator: Krumke, S. O.; Noltemeier, H. & Wirth, H. C.
System: The UNT Digital Library
Analysis, design, and implementation of PHENIX on-line computing systems software using Shlaer-Mellor object-oriented analysis and recursive design (open access)

Analysis, design, and implementation of PHENIX on-line computing systems software using Shlaer-Mellor object-oriented analysis and recursive design

An early prototype of the core software for on-line computing systems for the PHENIX detector at RHIC has been developed using the Shlaer-Mellor OOA/RD method, including the automatic generation of C++ source code using a commercial translation engine and {open_quotes}architecture{close_quotes}.
Date: February 16, 1997
Creator: Kozlowski, T.; Desmond, E. & Haggerty, J.
System: The UNT Digital Library
Diamond radiation detectors I. Detector properties for IIa diamond (open access)

Diamond radiation detectors I. Detector properties for IIa diamond

The detector properties and carrier dynamics of type IIa diamonds are reasonably well understood. The trends in the electron and hole mobilities have been characterized as a function of temperature, impurity content, electric field and carrier density. The carrier lifetimes are coupled through the nitrogen impurity. This leaves us with typical samples with collection distances of 20 to 50 micrometers. The detailed dynamics of the carriers can be modeled using a rate equation analysis. Much progress has been made in understanding the detector properties of diamond, but continued progress has been limited by the geologic processes used to make the material, for example sample size and no synthesis control. CVD diamond promises to eliminate these restrictions.
Date: May 16, 1997
Creator: Kania, D. R.
System: The UNT Digital Library
Peregrine monte carlo dose calculations for radiotherapy using clinically realistic neutron and proton beams (open access)

Peregrine monte carlo dose calculations for radiotherapy using clinically realistic neutron and proton beams

Lawrence Livermore National Laboratory (LLNL) has developed an all-particle Monte Carlo radiotherapy dose calculation code--PEREGRINE--for use in clinical radiation oncology. For PEREGRINE, we have assembled high-energy evaluated nuclear databases; created radiation source characterization and sampling algorithms; and simulated and characterized clinical beams for treatment with photons, neutrons and protons. Spectra are available for the Harper Hospital (Detroit, U.S.A.) Be(d,n) neutron therapy beam, the National Accelerator Centre (NAC, Faure, S.A.) Be(p,n) neutron therapy beam and many of the operating modes of the Loma Linda University Medical Center (LLUMC, Loma Linda, USA) proton treatment center. These beam descriptions are being used in PEREGRINE for Monte Carlo dose calculations on clinical configurations for comparisons to measurements. The methods of defining and sampling the beam phase space characterizations are discussed. We show calculations using these clinical beams compared to measurements in homogeneous water phantoms. The state of PEREGRINE's high energy neutron and proton transport database, PCSL, is reviewed and the remaining issues involving nuclear data needs for PEREGRINE are addressed.
Date: June 16, 1997
Creator: Cox, L. J., LLNL
System: The UNT Digital Library
Zephyr: a secure internet-based process to streamline engineering (open access)

Zephyr: a secure internet-based process to streamline engineering

None
Date: September 16, 1997
Creator: Jordan, C. W., LLNL
System: The UNT Digital Library