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Two exercises in supersymmetry: a low-energy supergravity model and free string field theory (open access)

Two exercises in supersymmetry: a low-energy supergravity model and free string field theory

The new features of a supersymmetric standard model in the presence of heavy families are studied. The minimal set of Higgs fields, the desert between the electroweak and the grand unification scale and perturbative values of the dimensionless parameters throughout this region are assumed. Using the numerical as well as the approximate analytic solution of the renormalization group equations, the evolution of all the parameters of the theory are studied in the case of large Yukawa couplings for the fourth family. The desired spontaneous symmetry breaking of the electroweak symmetry takes place only for a rather unnatural choice of the initial values of certain mass parameters at the grand unification scale. If it is gravitino mass smaller than 200 GeV the vacuum expectation values of the Higgs fields emerge necessarily in an interplay of the tree level Higgs potential and its quantum corrections and are approximately equal. The qurak masses of the fourth family are roughly 135 GeV, while the mass of the fourth charged lepton has an upper bound of 90 GeV. Further characteristic features of this scenario are one light neutral Higgs field of mass 50 GeV and gluino masses below 75 GeV. If the gravitino mass is …
Date: September 1, 1986
Creator: Preitschopf, C.R.
Object Type: Report
System: The UNT Digital Library
Use of molybdenum ion source electrodes at RTNS-II (open access)

Use of molybdenum ion source electrodes at RTNS-II

Reports are reported for an ongoing effort to optimize D+ beam production by the MATS-III ion source used at RTNS-II. The three seven-aperture electrodes, originally consisting of water-cooled copper, have now been tested using uncooled molybdenum and with water cooling on the second (decel) electrode only. Details of the change, the results of the testing, and the benefits in operation, performance and cost are given.
Date: September 29, 1986
Creator: Massoletti, D.J.; Harter, G.A. & Heikkinen, D.W.
Object Type: Article
System: The UNT Digital Library
Magnetic measurements of the transuranium elements. Progress report, January 1-December 31, 1986 (open access)

Magnetic measurements of the transuranium elements. Progress report, January 1-December 31, 1986

Magnetic measurements have been made on polycrystalline CfCl/sub 3/ in both a hexagonal and orthorhombic crystal form. The magnetic properties were studied as a function of crystal structure by converting the same sample back and forth from one form to the other. In a continuation of a study of the magnetic transition temperature as a function of actinide-actinide separation of the curium pnictide series we have undertaken magnetic measurements on curium bismuthide during this contract period. We have accomplished several milestones in our program to grow single crystals of actinide metals and compounds and determine their solid-state properties. Previous physical property measurements on transamericium actinide materials have been mainly limited to polycrystalline samples due to the limited availability of materials and the great material losses incurred during the common crystal growth methods. We have investigated a low-loss, microscale technique of crystal growth using lanthanides as non-radioactive stand-ins for the radioactive actinides.
Date: September 1, 1986
Creator: Nave, S.E.
Object Type: Report
System: The UNT Digital Library
LFCM vitrification technology. Quarterly progress report, January-March 1986 (open access)

LFCM vitrification technology. Quarterly progress report, January-March 1986

This report is compiled by the Nuclear Waste Treatment Progrqam and the Hanford Waste Vitrification Program at Pacific Northwest Laboratory to document progress on liquid-fed ceramic melter (LFCM) vitrification technology. Progress in the following technical subject areas during the second quarter of FY 1986 is discussed: melting process chemistry and glass development, feed preparation and transfer systems, melter systems, canister filling and handling systems, off-gas systems, and process/product modeling and control.
Date: September 1, 1986
Creator: Burkholder, H. C. & Minor, J. E.
Object Type: Report
System: The UNT Digital Library
Multiple track Doppler-shift spectroscopy system for TFTR neutral beam injectors (open access)

Multiple track Doppler-shift spectroscopy system for TFTR neutral beam injectors

A Doppler-shift spectroscopy system has been installed on the TFTR neutral beam injection system to measure species composition during both conditioning and injection pulses. Two intensified vidicon detectors and two spectrometers are utilized in a system capable of resolving data from up to twelve ion sources simultaneously. By imaging the light from six ion sources onto one detector, a cost-effective system has been achieved. Fiber optics are used to locate the diagnostic in an area remote from the hazards of the tokamak test cell allowing continuous access, and eliminating the need for radiation shielding of electronic components. Automatic hardware arming and interactive data analysis allow beam composition to be computed between tokamak shots for use in analyzing plasma heating experiments. Measurements have been made using lines of sight into both the neutralizer and the drift duct. Analysis of the data from the drift duct is both simpler and more accurate since only neutral particles are present in the beam at this location. Comparison of the data taken at these two locations reveals the presence of partially accelerated particles possessing an estimated 1/e half-angle divergence of 15/sup 0/ and accounting for up to 30% of the extracted power.
Date: September 1, 1986
Creator: Kamperschroer, J. H.; Kugel, H. W.; Reale, M. A.; Hayes, S. L.; Johnson, G. A.; Lowrance, J. L. et al.
Object Type: Report
System: The UNT Digital Library
Geothermal technology publications and related reports: a bibliography, January 1984-December 1985 (open access)

Geothermal technology publications and related reports: a bibliography, January 1984-December 1985

Technological limitations restrict the commercial availability of US geothermal resources and prevent effective evaluation of large resources, as magma, to meet future US needs. The US Department of Energy has asked Sandia to serve as the lead laboratory for research in Geothermal Technologies and Magma Energy Extraction. In addition, technology development and field support has been provided to the US Continental Scientific Drilling Program. Published results for this work from January 1984 through December 1985 are listed in this bibliography.
Date: September 1, 1986
Creator: Cooper, D.L. (ed.)
Object Type: Report
System: The UNT Digital Library
Guidelines and workbook for assessment of organization and administration of utilities seeking operating license for a nuclear power plant. Guidelines for utility organization and administration plan. Volume 1, Revision 1 (open access)

Guidelines and workbook for assessment of organization and administration of utilities seeking operating license for a nuclear power plant. Guidelines for utility organization and administration plan. Volume 1, Revision 1

Volumes 1 and 2 of this report are a partial response to the requirements of Item I.B.1.1 of the ''NRC Action Plan Developed as a Result of the TMI-2 Accident,'' NUREG-0660, and are designed to serve as a basis for replacing the earlier NUREG-0731, ''Guidelines for Utility Management Structure and Technical Resources.'' These Guidelines are intended to provide guidance to the user in preparing a written plan for a proposed nuclear organization and administration. The purpose of the Workbook (Vol. 2) is to guide the NRC reviewer through a systematic review and assessment of a proposed organization and administration. It is the NRC's intention to incorporate these Guidelines and Workbook into a future revision of the Standard Review Plan (SRP), NUREG-0800. However, at this time the report is being published so that the material may be used on a voluntary basis by industry to systematically prepare or evaluate their organization or administration plans. Use of the report by the NRC would not occur until after it has been incorpoarted in the SRP.
Date: September 1, 1986
Creator: Thurber, J. A.; Olson, J.; Osborn, R. N.; Sommers, P. & Widrig, R. D.
Object Type: Report
System: The UNT Digital Library
Method to rapidly tune the halo spoilers of the tevatron muon beam (open access)

Method to rapidly tune the halo spoilers of the tevatron muon beam

An active shield has been constructed which forms a sharp magnetic edge around the central core of useful muons and sweeps the envelope of halo muons (those that enter the aperture of an experiment without having passed through the momentum tagging system) radially away from beam center. Two types of halo scrapers have been employed in this shield: conventional toroidal magnets and a newly developed magnetic element called ''mupipe''. The mupipes have eight degrees of motion, so attempting to tune the mupipe system by systematic measurements over the full range of each coordinate would be impractical. An algorithm was formulated to take a small set of measured values and from them predict the required positions of the two sections of mupipe to obtain maximum beam and minimum halo. The algorithm measures the muon and halo yields at a representative subset of coordinated, employs a fitting program to find a functional form for the yields in terms of the coorinated, and maximizes that function in terms of the coordinates. The algorithm was tested by applying a Monte Carlo program to predict the halo and muon yield for a given orientation of the two movable sections of mupipe. (LEW)
Date: September 1, 1986
Creator: Ojeda, Y.; Scott, B.; Malensek, A. & Morfin, J.G.
Object Type: Report
System: The UNT Digital Library
Development of superconductors for applications in high-field, high-current-density magnets for fusion research (open access)

Development of superconductors for applications in high-field, high-current-density magnets for fusion research

The development of large-bore, high-field magnets for fusion energy applications requires a system approach to both magnet and conductor design. At Lawrence Livermore National Laboratory (LLNL), the criteria used to choose superconductors include: strain tolerance, radiation tolerance, heat removal, stability, fabricability, and cost. We report on the performance of industrially produced, prototype, Ti-modified Nb/sub 3/Sn wires developed with LLNL support. Wire performance characteristics evaluated include critical current as a function of magnetic field, temperature, and applied strain. Tests were performed to determine how this performance translates to the performance of a cable-in-conduit conductor system using this wire. An alternative to Nb/sub 3/Sn superconductors is NbN, which is strain and radiation insensitive. We report preliminary efforts to produce multifilamentary NbN conductors by liquid-metal infiltration of NbN-coated, high-strength fibers. In addition, we discuss the fabrication of multifilamentary NbN conductors and their possible impact on magnet design.
Date: September 26, 1986
Creator: Summers, L. T. & Miller, J. R.
Object Type: Article
System: The UNT Digital Library
Spectroscopic analysis of low Z impurities in the Tandem Mirror Experiment-upgrade (open access)

Spectroscopic analysis of low Z impurities in the Tandem Mirror Experiment-upgrade

Two absolutely calibrated EUV instruments have been used to study the impurity characteristics in the Tandem Mirror Experiment-Upgrade (TMX-U). One instrument is a normal incidence spectrograph that measures the time histories of several impurity emission lines (300 to 1800 A) in a single shot; radial scans can be obtained on a shot-by-shot basis. The other instrument is a monochromator that measures time-resolved radial profiles of a given impurity emission line in a single shot. The common intrinsic impurities measured in TMX-U are C,N,O and Ti. It has been shown that large fractions of the oxygen and nitrogen in the plasma are associated with the neutral beams while the main source of carbon is the plasma wall. In general, the concentration of each of the impurities is low (<1%), and the power radiated by them is less than 10 kW, which is a small portion of the total input power to the plasma. The concentrations of the impurities can be reduced substantially blow discharge cleaning and titanium gettering. No significant accumulation of impurity ions in the thermal barrier region has been observed.
Date: September 1, 1986
Creator: Yu, T.L.
Object Type: Report
System: The UNT Digital Library
Atlas of atomic spectral lines of plutonium emitted by an inductively coupled plasma (open access)

Atlas of atomic spectral lines of plutonium emitted by an inductively coupled plasma

Optical emission spectra from high-purity Pu-242 were generated with a glovebox-enclosed inductively coupled plasma (ICP) source. Spectra covering the 2280 to 7008 Angstrom wavelength range are presented along with general commentary on ICP-Pu spectroscopy.
Date: September 1, 1986
Creator: Edelson, M. C.; DeKalb, E. L.; Winge, R. K. & Fassel, V. A.
Object Type: Report
System: The UNT Digital Library
Reconnaissance of intertidal and subtidal zones of Back Island, Behm Canal, Southeast Alaska (open access)

Reconnaissance of intertidal and subtidal zones of Back Island, Behm Canal, Southeast Alaska

A diver reconnaissance of the intertidal and subtidal zones of Back Island, Southeast Alaska, was performed May 20-22, 1986. The specific objectives were to catalog potentially vulnerable shellfish, other invertebrates, and plant resources, and to identify potential herring spawning sites. This effort was designed to supplement the existing ecological data base for Back Island that would be used during the National Environmental Policy Act (NEPA) documentation process. A NEPA document will be prepared that describes the site environment and assesses impacts from the proposed construction and operation of the Southeast Alaska Acoustic Measurement Facility (SEAFAC). Nine diver transects were established around Back Island. Particular attention was devoted to proposed locations for the pier and float facilities and range-operations and shore-power cable run-ups.
Date: September 1, 1986
Creator: Strand, J. A. & Young, J. S.
Object Type: Report
System: The UNT Digital Library
Literature review of the concentration ratios of selected radionuclides in freshwater and marine fish (open access)

Literature review of the concentration ratios of selected radionuclides in freshwater and marine fish

Concentration ratios (CR's) used for modeling the uptake and food chain transport of radionuclides in fish have usually been conservative; that is, at the high end of reported values. This practice ensures that the dose to the consumer of contaminated fish will not be underestimated. In many models, however, conservative values have been used for all variables that have any uncertainty associated with them. As a result the dose to the consumer is overestimated. Realistic CR values need to be developed to establish model parameters that will accurately reflect tissue burdens in fish and resulting dose rates to consumers. This report reviews and summarizes published literature on the uptake and distribution of stable and radioactive isotopes of 26 elements. Based on this review, we have made recommendations on CR values to be used for modeling the accumulation of radionuclides in fish. Our recommendations are compared with CR values reported in other publications. A generic discussion of abiotic and biotic factors that influence CR values is provided so that CR values may be adjusted based on site-specific characteristics of the fishes habitat. Recommended CR values for freshwater fish and for marine fish are listed. Although this report emphasizes radionuclides, it is …
Date: September 1, 1986
Creator: Poston, T. M. & Klopfer, D. C.
Object Type: Report
System: The UNT Digital Library
Panel discussion on laboratory accelerator programs: present and future (open access)

Panel discussion on laboratory accelerator programs: present and future

The present SLAC accelerator program is summarized briefly, and the future of electron-positron colliders is discussed. Present activities discussed include the PEP storage ring, the SPEAR storage ring, the Linear Accelerator, and the SLAC Linear Collider (SLC) project. Future prospects include a larger scale linear collider. The stability requirements on acceleration are briefly discussed. (LEW)
Date: September 1, 1986
Creator: Richter, B.
Object Type: Article
System: The UNT Digital Library
Oxide cathode lifetime improvements at RTNS-II (open access)

Oxide cathode lifetime improvements at RTNS-II

Results are reported for an ongoing effort to optimize D/sup +/ beam production by the MATS-III ion source used at the RTNS-II. The oxide cathode assembly originally designed for lower power operation has been modified and redesigned for higher electron current yield, longer life and serviceability. A factor of 2.5 has been gained in cathode lifetime due to these changes. The details of the changes and results and benefits in operation and performance are given. In addition, the technique used for manufacture of the filament is described.
Date: September 29, 1986
Creator: Massoletti, D.J.
Object Type: Article
System: The UNT Digital Library
Waste management system alternatives for treatment of wastes from spent fuel reprocessing (open access)

Waste management system alternatives for treatment of wastes from spent fuel reprocessing

This study was performed to help identify a preferred TRU waste treatment alternative for reprocessing wastes with respect to waste form performance in a geologic repository, near-term waste management system risks, and minimum waste management system costs. The results were intended for use in developing TRU waste acceptance requirements that may be needed to meet regulatory requirements for disposal of TRU wastes in a geologic repository. The waste management system components included in this analysis are waste treatment and packaging, transportation, and disposal. The major features of the TRU waste treatment alternatives examined here include: (1) packaging (as-produced) without treatment (PWOT); (2) compaction of hulls and other compactable wastes; (3) incineration of combustibles with cementation of the ash plus compaction of hulls and filters; (4) melting of hulls and failed equipment plus incineration of combustibles with vitrification of the ash along with the HLW; (5a) decontamination of hulls and failed equipment to produce LLW plus incineration and incorporation of ash and other inert wastes into HLW glass; and (5b) variation of this fifth treatment alternative in which the incineration ash is incorporated into a separate TRU waste glass. The six alternative processing system concepts provide progressively increasing levels of TRU …
Date: September 1, 1986
Creator: McKee, R. W.; Swanson, J. L.; Daling, P. M.; Clark, L. L.; Craig, R. A.; Nesbitt, J. F. et al.
Object Type: Report
System: The UNT Digital Library
Nuclear de-excitation processes following medium energy heavy ion collisions (open access)

Nuclear de-excitation processes following medium energy heavy ion collisions

As heavy ion reaction studies have progressed from beam energies below 10 MeV/nucleon to higher energies, many non-equilibrium reaction phenomena have been observed. Among these are nucleon emission with velocities in excess of the beam velocity, incomplete momentum transfer to evaporation residue and fission-like fragments, ..gamma..-rays with energies in excess of 100 MeV, and ..pi../sup 0/ production when beam energies are below the threshold for production by the nucleon-nucleon collision mechanism. Additionally, prefission neutrons have been observed in excess of numbers expected from equilibrium models. A few of the approaches which have been applied to these phenomena are as follows: Intranuclear cascade: two body collisions are assumed to mediate the equilibration. The geometry and momentum space is followed semiclassically. The approach has many successes though it may suffer in a few applications is not following holes; TDHF considers one body processes only; in the energy regime of interest, two body processes are important so that this may not be a viable approach; Boltzmann-Uehling-Uhlenbeck or Vlasov-Uehling-Uhlenbeck (BUU/VUU) equations combine both one body and two body dynamics. The spatial and momentum evolution of the reactions are followed in a mean field. These should be the Cadillacs of the models. They are computationally …
Date: September 1, 1986
Creator: Blann, M.
Object Type: Article
System: The UNT Digital Library
Bacteria transport through porous media. Annual report, December 31, 1984 (open access)

Bacteria transport through porous media. Annual report, December 31, 1984

The following five chapters in this report have been processed separately for inclusion in the Energy Data Base: (1) theoretical model of convective diffusion of motile and non-motile bacteria toward solid surfaces; (2) interfacial electrochemistry of oxide surfaces in oil-bearing sands and sandstones; (3) effects of sodium pyrophosphate additive on the ''huff and puff''/nutrient flooding MEOR process; (4) interaction of Escherichia coli B, B/4, and bacteriophage T4D with Berea sandstone rock in relation to enhanced oil recovery; and (5) transport of bacteria in porous media and its significance in microbial enhanced oil recovery.
Date: September 1, 1986
Creator: Yen, T.F.
Object Type: Report
System: The UNT Digital Library
Pellet fueling development at ORNL (open access)

Pellet fueling development at ORNL

Advanced plasma fueling systems for magnetic confinement devices are being developed at the Oak Ridge National Laboratory (ORNL). The general approach is that of producing and accelerating frozen hydrogenic pellets at speeds in the range of 1-2 km/s and higher. Two specific concepts are under development: (1) high-speed pneumatic acceleration; and (2) mechanical (centrifugal) acceleration. Both approaches are being pursued to meet the projected pellet size and delivery rates for major near-term plasma confinement devices, such as the Tokamak Fusion Test Reactor (TFTR), Tore Supra, the Joint European Torus (JET), JT-60, and Doublet III-D (DIII-D), as well as future applications. In addition to these confinement physics related activities, ORNL is pursuing advanced technologies to achieve pellet velocities significantly in excess of the 2-km/s range already attained with pneumatic injectors and has embarked on a development program designed to explore the feasibility of fabricating and accelerating tritium pellets. This paper describes these ongoing activities.
Date: September 1, 1986
Creator: Combs, S. K.; Milora, S. L.; Foster, C. A.; Schuresko, D. D.; Foust, C. R.; Simmons, D. W. et al.
Object Type: Article
System: The UNT Digital Library
Proceedings of the 1986 workshop on advanced time-of-flight neutron powder diffraction (open access)

Proceedings of the 1986 workshop on advanced time-of-flight neutron powder diffraction

This report contains abstracts of talks and summaries of discussions from a small workshop held to discuss the future of time-of-flight neutron powder diffraction and its implementation at the Los Alamos Neutron Scattering Center. 47 refs., 3 figs.
Date: September 1, 1986
Creator: Lawson, A. C. & Smith, K. (comps.)
Object Type: Article
System: The UNT Digital Library
Update on the tevatron muon shield (open access)

Update on the tevatron muon shield

In 1984, the dichromatic train was installed for an initial set of tests. Along with these tests of train performance, measurements of muon rates at various depths in the berm were taken in order to check Monte Carlo predictions. Data were taken at a range of train momentum settings, and from a bare target. The results of those studies are presented here and compared to predictions. In 1985, the quadrupole triplet train was installed for a wide band neutrino run. During this run, 5.5 m of 1.8 m diameter lead was installed at the request of the experimenters to harden the shield. Data obtained during this triplet run under a variety of conditions are also presented, and compared to Monte Carlo predictions. Finally, these results are used to determine how much additional shielding is needed for higher energy operation.
Date: September 15, 1986
Creator: Malensek, A. & Stutte, L.
Object Type: Report
System: The UNT Digital Library
Performance of low pressure tissue equivalent chambers and a new method for parameterizing the dose equivalent (open access)

Performance of low pressure tissue equivalent chambers and a new method for parameterizing the dose equivalent

The performance of spherical tissue equivalent chambers with equivalent diameters between 0.5 and 2..mu.. was tested experimentally using monoenergetic and polyenergetic neutron sources in the energy region of 10 keV to 14.5 MeV. Theoretical calculations were performed in order to obtain a simple algorithm for deriving the dose equivalent from the measured data. The algorithm relates the number of recoil particles to the dose equivalent, rather than having a one-to-one correspondence between the lineal energy and the linear energy transfer of the recoil particles. The calculations took into account neutron interactions with hydrogen atoms in the chamber wall as well as in the gas, and also the finite energy resolution determined by both the detector and the electronic system. Qualitatively, the calculations well dscribe the experimental results. The algorithm that was developed determines the neutron dose equivalent, from the data of the 0.5..mu.. chamber, to better than +-20% over the energy range of 30 keV to 14.5 MeV. The same algorithm also determines the dose equivalent from the data of the 2..mu.. chamber to better than +-20% over the energy of 70 keV to 14.5 MeV. The efficiency of the chambers is low and has an average value of 330 …
Date: September 1, 1986
Creator: Eisen, Y.; Vasilik, D. G.; Brake, R. J.; Erkkila, B. H. & Littlejohn, G. J.
Object Type: Report
System: The UNT Digital Library
Reactor-specific spent fuel discharge projections: 1985 to 2020 (open access)

Reactor-specific spent fuel discharge projections: 1985 to 2020

The creation of four spent-fuel data bases that contain information on the projected amounts of spent fuel to be discharged from US commercial nuclear reactors through the year 2020 is described. The data bases contain detailed spent-fuel information from existing, planned, and projected pressurized water reactors (PWR) and boiling water reactors (BWR). The projections are based on individual reactor information supplied by the US reactor owners. The basic information is adjusted to conform to Energy Information Agency (EIA) forecasts for nuclear installed capacity, generation, and spent fuel discharged. The EIA cases considered are: (1) No New Orders with Extended Burnup, (2) No New Orders with Constant Burnup, (3) Middle Case with Extended Burnup, and (4) Middle Case with Constant Burnup. Detailed, by-reactor tables are provided for annual discharged amounts of spent fuel, for storage requirements assuming maximum-at-reactor storage, and for storage requirements assuming maximum-at-reactor plus intra-utility transshipment of spent fuel.
Date: September 1, 1986
Creator: Heeb, C. M.; Libby, R. A.; Walling, R. C. & Purcell, W. L.
Object Type: Report
System: The UNT Digital Library
Moessbauer effect of europium metal under pressure (open access)

Moessbauer effect of europium metal under pressure

The pressure dependence of the magnetic hyperfine field and of the isomer shift of /sup 151/Eu in europium metal has been studied in a diamond anvil pressure cell at low temperatures. In the pressure range 0-12 GPa at 44/sup 0/K (T/sub N/ = 90/sup 0/K), the magnetic hyperfine field changes from -22 T to -8 T while the isomer shift increases from -7.3 to -3.8 mm s/sup -1/ relative to a SmF/sub 3/ source. The changes are interpreted as indicative of a pressure-driven intermediate valence state causing a reduced magnetic moment in Eu. Intermediate valence and magnetic order coexist over the range of pressures studied.
Date: September 1, 1986
Creator: Taylor, R. D. & Farrell, J. N.
Object Type: Article
System: The UNT Digital Library