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Spontaneous breaking of supersymmetry (open access)

Spontaneous breaking of supersymmetry

There has been recently a revival of interest in supersymmetric gauge theories, stimulated by the hope that supersymmetry might help in clarifying some of the questions which remain unanswered in the so called Grand Unified Theories and in particular the gauge hierarchy problem. In a Grand Unified Theory one has two widely different mass scales: the unification mass M approx. = 10/sup 15/GeV at which the unification group (e.g. SU(5)) breaks down to SU(3) x SU(2) x U(1) and the mass ..mu.. approx. = 100 GeV at which SU(2) x U(1) is broken down to the U(1) of electromagnetism. There is at present no theoretical understanding of the extreme smallness of the ratio ..mu../M of these two numbers. This is the gauge hierarchy problem. This lecture attempts to review the various mechanisms for spontaneous supersymmetry breaking in gauge theories. Most of the discussions are concerned with the tree approximation, but what is presently known about radiative correction is also reviewed.
Date: December 1, 1981
Creator: Zumino, B.
System: The UNT Digital Library
Digital neutron radiography using plane converters with multiwire proportional chambers (open access)

Digital neutron radiography using plane converters with multiwire proportional chambers

The work described here was completed more than three years ago, and represents, in large part the PhD and MS thesis research of two of the present authors. Much of it has been reported previously elsewhere. It constitutes an effort to develop and study a moderately low cost, moderate resolution, high sensitivity, on-line method for digital neutron radiography, intended for use where neutron fluence was limited by source strength, or received dose. The basic imaging system consisted of a position-sensitive gas proportional chamber together with its associated imaging electronics, and a plane neutron converter. Enriched-boron, gadolinium, and polyethylene (for fast neutrons) converters were analyzed and tested. Some work was done on digital data enhancement, and efforts to improve spatial resolution included pressurizing the proportional-chamber gas to reduce the track lengths of the neutron-interaction products.
Date: December 1, 1981
Creator: Kaplan, S. N.; Director, B. A.; Perez-Mendez, V. & Valentine, K. H.
System: The UNT Digital Library
Development of annular-coated-pressurized and sphere-pac LWR fuels (open access)

Development of annular-coated-pressurized and sphere-pac LWR fuels

Annular-coated (graphite)-pressurized and sphere-pac fuel rod designs, which are expected to exhibit improved PCI-failure resistance, and, thus, more reliable extended burnup performance, are being developed. Data sufficient to provide the technical bases needed to license lead test assemblies of the improved designs for irradiation in commercial LWRs are being obtained. Out-of-reactor experiments, in-reactor instrumented experiments, in-reactor power-ramp tests, and lead-rod demonstration irradiations are providing the needed data to support the technical bases. Results obtained to-date confirm the expected performance improvement compared with a solid-pellet reference design. The degree of improvement with respect to PCI-resistance remains to be quantified during forthcoming power-ramp tests on fuel rod segments irradiated to moderate burnup levels in a commercial LWR.
Date: December 1, 1981
Creator: Buckman, F. W.; Crouthamel, C. E.; Freshley, M. D. & Barner, J. O.
System: The UNT Digital Library
Selected transuranic waste immobilization systems (open access)

Selected transuranic waste immobilization systems

Waste contaminated with transuranic (TRU) elements may require treatment prior to final disposal. Pacific Northwest Laboratory has conducted research and development to identify and characterize the wastes; to evaluate the possible immobilization requirements and treatment alternatives; and to develop immobilization process technologies. This paper describes systems that are anticipated to be capable of immobilizing a selected TRU waste stream consisting of a blend of process sludge and incinerator ash. The selected waste streams are based on the waste compositions generated at the Rocky Flats Plant, Golden, Colorado. The specific process and waste forms are: in-can glass melting, borosilicate glass monolith; joule-heated glass melting, borosilicate/aluminosilicate glass monolith; glass marble, borosilicate/aluminosilicate glass marble; basalt glass-ceramic, basalt glass-ceramic monolith; cast cement, cast cement monolith; pressed cement, pressed cement pellet; and cold-pressed sintered ceramic, pressed ceramic pellet.
Date: December 1, 1981
Creator: Timmerman, C.L.; Treat, R.L. & Ross, W.A.
System: The UNT Digital Library
Constructibility issues associated with a nuclear waste repository in basalt (open access)

Constructibility issues associated with a nuclear waste repository in basalt

This report contains the text and slide reproductions of a speech on nuclear waste disposal in basalt. The presentation addresses the layout of repository access shafts and subsurface facilities resulting from the conceptual design of a nuclear repository in basalt. The constructibility issues that must be resolved prior to construction are described. (DMC)
Date: December 4, 1981
Creator: Turner, D.A.
System: The UNT Digital Library
Occurrence and use of complex resonances (poles in scattering and radiation problems) (open access)

Occurrence and use of complex resonances (poles in scattering and radiation problems)

In a wide variety of physics problems, especially those which involve wave phenomena such as in electromagnetics and acoustics, a behavior results that can be described by systems of linear (partial) differential equations. Solutions to such problems often can be expressed simply in the form of an exponential series. Some specific background material for this approach is discussed, and a variety of example applications is summarized. (WHK)
Date: December 15, 1981
Creator: Miller, E. K.
System: The UNT Digital Library
Overview of geotechnical methods to characterize rock masses (open access)

Overview of geotechnical methods to characterize rock masses

The methods that are used to characterize discontinuous rock masses from a geotechnical point of view are summarized. Emphasis is put on providing key references on each subject. The topics of exploration, in-situ stresses, mechanical properties, thermal properties, and hydraulic properties are addressed.
Date: December 1, 1981
Creator: Heuze, F.E.
System: The UNT Digital Library
Laser-damage thresholds of thin-film optical coatings at 248 nm (open access)

Laser-damage thresholds of thin-film optical coatings at 248 nm

We have measured the laser-induced damage thresholds for 248 nm wavelength light of over 100 optical coatings from commercial vendors and research institutions. All samples were irradiated once per damage site with temporally multi-lobed, 20-ns pulses generated by a KrF laser. The survey included high, partial, and dichroic reflectors, anti-reflective coatings, and single layer films. The samples were supplied by ten vendors. The majority of samples tested were high reflectors and antireflective coatings. The highest damage thresholds were 8.5 to 9.4 J/cm/sup 2/, respectively. Although these represent extremes of what has been tested so far, several vendors have produced coatings of both types with thresholds which consistently exceed 6 J/cm/sup 2/. Repeated irradiations of some sites were made on a few samples. These yielded no degradation in threshold, but in fact some improvement in damage resistance. These same samples also exhibited no change in threshold after being retested seven months later.
Date: December 11, 1981
Creator: Milam, D.; Rainer, F. & Lowdermilk, W.H.
System: The UNT Digital Library
Magnetron co-sputtering system for coating ICF targets (open access)

Magnetron co-sputtering system for coating ICF targets

Fabrication of Inertial Confinement Fusion (ICF) targets requires deposition of various types of coatings on microspheres. The mechanical strength, and surface finish of the coatings are of concern in ICF experiments. The tensile strength of coatings can be controlled through grain refinement, selective doping and alloy formation. We have constructed a magnetron co-sputtering system to produce variable density profile coatings with high tensile strength on microspheres. The preliminary data on the properties of a Au-Cu binary alloy system by SEM and STEM analysis is presented.
Date: December 9, 1981
Creator: Hsieh, E. J.; Meyer, S. F.; Halsey, W. G.; Jameson, G. T. & Wittmayer, F. J.
System: The UNT Digital Library
Hamiltonian structure of multi-species fluid electrodynamics (open access)

Hamiltonian structure of multi-species fluid electrodynamics

The phase space for multi-species fluid electrodynamics is the function space of fluid variables and Maxwell field variables. The Poisson bracket on phase functionals is constructed as a Lie algebra product following general methods of infinite dimensional symplectic geometry.
Date: December 1, 1981
Creator: Spencer, R.G.
System: The UNT Digital Library
Initial-state interactions, factorization, and the Drell-Yan process (open access)

Initial-state interactions, factorization, and the Drell-Yan process

It is shown that initial state interactions violate the factorization conjecture for the Drell-Yan process order by order in perturbation theory. Also, the effects of elastic and inelastic initial state interactions on the observed cross sections are discussed.
Date: December 1, 1981
Creator: Bodwin, G. T.; Brodsky, S. J. & Lepage, G. P.
System: The UNT Digital Library
Coatings for laser fusion (open access)

Coatings for laser fusion

Optical coatings are used in lasers systems for fusion research to control beam propagation and reduce surface reflection losses. The performance of coatings is important in the design, reliability, energy output, and cost of the laser systems. Significant developments in coating technology are required for future lasers for fusion research and eventual power reactors.
Date: December 18, 1981
Creator: Lowdermilk, W.H.
System: The UNT Digital Library
Designing cost accounting models for woody biomass systems and direct applications of geothermal energy (open access)

Designing cost accounting models for woody biomass systems and direct applications of geothermal energy

A framework for determining the characteristics of cost accounting models most appropriate to evaluating energy technologies at different stages in their development is outlined. This analytical perspective is used to evaluate existing models for wood energy plantations and for direct (non-electric) applications of geothermal energy. The concern is with micro-economic cost estimation systems based on a simulation of the technology's physical plant and the projected cash flow resulting from the investment. For discussion purposes three general stages of technology evaluation are described. The level of detail in the engineering simulation should increase as the evaluation progresses through the three stages. Too much detail in the preliminary stage restricts applicability of model outputs to specific system designs, some of which may be inappropriate for other potentially attractive applications. The economic analysis should gradually shift from a general economic perspective on all costs and benefits of system operation to a more specific depiction of cash flows as seen by project developers. Unfortunately, developers of cost models for both woody biomass plantations and direct applications of geothermal energy appear to build all the engineering and financial detail available into their models. They then apply them to any stage in the evaluation process to …
Date: December 1, 1981
Creator: Barron, W.F. & Perlack, R.D.
System: The UNT Digital Library
Hamiltonian kinetic theory of plasma ponderomotive processes (open access)

Hamiltonian kinetic theory of plasma ponderomotive processes

The nonlinear nonresonant interaction of plasma waves and particles is formulated in a Hamiltonian kinetic theory which treats the wave-action and particle distributions on an equal footing, thereby displaying reciprocity relations. In the quasistatic limit, a nonlinear wave-kinetic equation is obtained. The generality of the formalism allows for applications to arbitrary geometry, with the nonlinear effects expressed in terms of the linear susceptibility.
Date: December 1, 1981
Creator: McDonald, S. W. & Kaufman, A. N.
System: The UNT Digital Library
Review of 1064-nm damage tests of electron-beam deposited Ta/sub 2/O/sub 5//SiO/sub 2/ antireflection coatings (open access)

Review of 1064-nm damage tests of electron-beam deposited Ta/sub 2/O/sub 5//SiO/sub 2/ antireflection coatings

Damage tests of Ta/sub 2/O/sub 5//SiO/sub 2/ antireflection films deposited under a variety of conditions showed that thresholds of films deposited at 175/sup 0/C were greater than thresholds of films deposited at either 250/sup 0/C or 325/sup 0/C. Deposition at high rate and low oxygen pressure produced highly absorptive films with low thresholds. Thresholds did not correlate with film reflectivity or net stress in the films, and correlated with film absorption only when the film absorption was greater than 10/sup 4/ ppM. Baking the films for four hours at 400/sup 0/C reduced film absorption, altered net film stress, and produced an increase in the average damage threshold.
Date: December 18, 1981
Creator: Milam, D.; Rainer, F.; Lowdermilk, W.H.; Swain, J.E.; Carniglia, C.K. & Hart, T.T.
System: The UNT Digital Library
On-line validation of linear process models using generalized likelihood ratios. [PWR] (open access)

On-line validation of linear process models using generalized likelihood ratios. [PWR]

A real-time method for testing the validity of linear models of nonlinear processes is described and evaluated. Using generalized likelihood ratios, the model dynamics are continually monitored to see if the process has moved far enough away from the nominal linear model operating point to justify generation of a new linear model. The method is demonstrated using a seventh-order model of a natural circulation steam generator.
Date: December 1, 1981
Creator: Tylee, J.L.
System: The UNT Digital Library
Economic feasibility of geothermal district heating: a case study (open access)

Economic feasibility of geothermal district heating: a case study

The application of a computerized methodology developed at Brookhaven National Laboratory (BNL) to an assessment of the economic feasibility of district heating in Reno, Nevada is described. To apply this methodology, assumptions concerning the characteristics of the heat load served, the price of competing fuels, and alternate forms of district heat utility ownership are combined with data describing the geothermal resource. Using these inputs along with engineering costs for geothermal field development and pipe installation, the methodology generates detailed engineering and economic descriptors of several proposed district heating systems. The impact of alternate construction expenditure schedules, retrofit costs, and system size on the unit cost of district heat is examined.
Date: December 1, 1981
Creator: Reisman, A. & Peterson, E.
System: The UNT Digital Library
Correlation of macroscopic material properties with microscopic nuclear data (open access)

Correlation of macroscopic material properties with microscopic nuclear data

Two primary irradiation-induced changes occur during neutron irradiation: the displacement of atoms forming crystal defects and the transmutation of atoms into either gaseous or solid products. The material scientist studying irradiation damage to material by fusion-produced neutrons is faced with several questions: Is the nature of high-energy (14-MeV) displacement damage the same as or different from that caused by fission neutrons (< 2 MeV). How do the high helium concentrations expected in a fusion environment affect the material properties. What effects do solid transmutation products have on the behavior of the irradiated materials. In the past few years, much work has been done to answer these questions. This paper reviews recent work in this area.
Date: December 18, 1981
Creator: Simons, R.L.
System: The UNT Digital Library
Computer-based test system for the Tactical Airfield Attack Munition (TAAM) safing, arming, and fuzing system (open access)

Computer-based test system for the Tactical Airfield Attack Munition (TAAM) safing, arming, and fuzing system

Testing and quality assurance of large numbers of firing systems are an essential part of the development of the Tactical Airfield Attack Munition (TAAM). A computerized test and data acquisition system has been developed to make the testing and quality assurance workload manageable. The system hardware utilizes an LSI-11/23 computer, a Tektronix 7612 transient digitizer, and various other programmable instruments and power supplies. The system is capable of measuring and analyzing mechanical shock and fireset transient waveforms, automating testing sequences, and making records and comparisons of the test results. The system architecture is flexible for general purpose firing system development work.
Date: December 1, 1981
Creator: Warhus, J.; Castleton, R. & Lanning, S.
System: The UNT Digital Library
Universality of Charged Multiplicity Distributions (open access)

Universality of Charged Multiplicity Distributions

The charged multiplicity distributions of the diffractive and non-diffractive components of hadronic interactions, as well as those of hadronic states produced in other reactions, are described well by a universal Gaussian function that depends only on the available mass for pionization, has a maximum at n{sub o} {approx_equal} 2M{sup 1/2}, where M is the available mass in GeV, and a peak to width ratio n{sub o}/D {approx_equal} 2.
Date: December 1, 1981
Creator: Goulianos, K.
System: The UNT Digital Library
Liquid-drop technique for generation of organic glass and metal shells (open access)

Liquid-drop technique for generation of organic glass and metal shells

We have for several years utilized the technique of capillary wave synchronization of the break-up of single and multiple component jets to produce uniform sized liquid drops and solid particles, and hollow liquid and solid shells. The technique has also been used to encapsulate a number of liquids in impermeable spherical shells. Highly uniform glass shells have been made by generating uniform drops of glass forming materials in an aqueous solution, subsequently evaporating the water, and then fusing and blowing the remaining solids in a high temperature vertical tube furnace. Experimental results will be presented and the critical problems in further research in this field will be discussed.
Date: December 23, 1981
Creator: Hendricks, C.D.
System: The UNT Digital Library
Study of emergency-action levels for light water reactors (open access)

Study of emergency-action levels for light water reactors

An emergency action level (EAL) is an observation or judgment that forms the basis for declaring an emergency status at a nuclear generating facility. There are four graded emergency category classifications which indicate an increasing potential for offsite radiological impact. Each emergency category is normally associated with an implementation procedure that outlines the preplanned actions that the emergency director will undertake. Thus a transient which causes a system or parameter to reach an EAL will also cause a transition of the normal station organization to an emergency organization. This transition will include an augmentation of the basic shift staff in order to support the corrective and mitigative actions of the nuclear reactor operators. In this regard, the major purpose of EALs is to provide an early indication of potential problems. Ideally, the ensuing response of the emergency organization will prevent a propagation of errors or failures that could result in serious consequences.
Date: December 1, 1981
Creator: Desrosiers, A.E.
System: The UNT Digital Library
Proceedings of the workshop on radioactivity associated with coal use (open access)

Proceedings of the workshop on radioactivity associated with coal use

A workshop on radioactivity in coal use was held on September 15 through 17, 1981, under the auspices of the US Department of Energy, Office of Environmental Programs, and the Los Alamos National Laboratory. The purpose of the workshop was to identify research issues associated with radioactivity resulting from the use of coal for electric power generation. The concensus of the 10 scientists participating in the workshop was that a moderate to strong need exists for research in solubility of fly ash in different fluids and for determination of radioactivity in construction materials. Several additional research issues were identified but were given a lower priority. Summaries of each presentation are included. Titles are: some effects of coal combustion on the radiation environment; radionuclides in western coal at Mound; low-level radiation in coals utilized and ashes produced at New York State electric utilities; radioactivity from coal use - where are the problems; chemistry of radionuclides in coal preparation; uranium daughters in natural atmospheric aerosols and coal-fired power plant emissions; possible contributions of coal extraction and utilization to radioactivity contributions in drinking water; and impact on water quality from radionuclides in coal. One paper has been abstracted separately for inclusion in the …
Date: December 1, 1981
Creator: unknown
System: The UNT Digital Library
Comparative analysis of polycyclic aromatic sulfur heterocycles isolated from four shale oils. [Polycyclic aromatic sulfur heterocycles; thiophenes] (open access)

Comparative analysis of polycyclic aromatic sulfur heterocycles isolated from four shale oils. [Polycyclic aromatic sulfur heterocycles; thiophenes]

This report describes the isolation of sulfur heterocycle fractions from four shale oils (Paraho, Geokinetics, Occidental, and Rio Blanco), the use of capillary column gas chromatography and mass spectrometry for the identification of individual mixture components, and a reverse (Ames) and forward mutation assay with Salmonella typhimurium to screen for possible health hazards. The major components of the Polycyclic Aromatic Sulfur Heterocycles (PASH) fractions for all four shale oils were found to be two- to three-ringed parent and alkylated thiophene compounds. In all cases the PASH fractions showed no more specific mutagenic response than the neutral PAC fractions from which they were isolated. The only mutagenic response which was detected in the PASH fractions was for the Rio Blanco shale oil and showed specific mutagenic response similar to the neutral PAC fraction from which it was isolated. Finally, the forward mutation 8-azaguanine test was apparently more sensitive than the Ames histidine reversion test in detecting mutagenic activity for the chemical fractions from the shale oils.
Date: December 1, 1981
Creator: Willey, C.; Pelroy, R. & Stewart, D.
System: The UNT Digital Library