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Proceedings of the LAMPF workshop on physics with polarized nuclear targets (open access)

Proceedings of the LAMPF workshop on physics with polarized nuclear targets

Topics of discussion included static and dynamic methods for polarizing nuclei, proton and pion nucleus scattering experiments, and possible future experiments at LAMPF. Separate abstracts were prepared for 11 papers in this report. (DWL)
Date: August 1, 1986
Creator: Burleson, G.; Gibbs, W.; Hoffmann, G.; Jarmer, J. J. & Tanaka, N. (eds.)
Object Type: Article
System: The UNT Digital Library
Construction and testing of the Mirror Fusion Test Facility magnets (open access)

Construction and testing of the Mirror Fusion Test Facility magnets

This paper describes the construction and testing of the Mirror Fusion Test Facility superconducting magnet set. Construction of the first Yin Yang magnet was started in 1978. And although this particular magnet was later modified, the final construction of these magnets was not completed until 1985. When completed these 42 magnets weighed over 1200 tonnes and had a maximum stored energy of approximately 1200 MJ at full field. Together with power supplies, controls and liquid nitrogen radiation shields the cost of the fabrication of this system was over $100M. General Dynamics/Convair Division was responsible for the system design and the fabrication of 20 of the magnets. This contract was the largest single procurement action at the Lawrence Livermore National Laboratory. During the PACE acceptance tests, the 26 major magnets were operated at full field for more than 24 hours while other MFTF subsystems were tested. From all of the data, the magnets operated to the performance specifications. For physics operation in the future, additional helium and nitrogen leak checking and repair will be necessary. In this report we will discuss the operation and testing of the MFTF Magnet System, the world's largest superconducting magnet set built to date. The topics …
Date: August 1, 1986
Creator: Kozman, T.; Shimer, D.; VanSant, J. & Zbasnik, J.
Object Type: Article
System: The UNT Digital Library
Physics of antimatter-matter reactions for interstellar propulsion (open access)

Physics of antimatter-matter reactions for interstellar propulsion

At the stage of the antiproton-nucleon annihilation chain of events relevant to propulsion the annihilation produces energetic charged pions and gamma rays. If annihilation occurs in a complex nucleus, protons, neutrons, and other nuclear fragments are also produced. The charge, number, and energy of the annihilation products are such that annihilation rocket engine concepts involving relatively low specific impulse (I/sub sp/ approx. = 1000 to 2000 s) and very high I/sub sp/ (3 x 10/sup 7/ s) appear feasible and have efficiencies on the order of 50% for annihilation energy to propulsion energy conversion. At I/sub sp/'s of around 15,000 s, however, it may be that only the kinetic energy of the charged nuclear fragments can be utilized for propulsion in engines of ordinary size. An estimate of this kinetic energy was made from known pieces of experimental and theoretical information. Its value is about 10% of the annihilation energy. Control over the mean penetration depth of protons into matter prior to annihilation is necessary so that annihilation occurs in the proper region within the engine. Control is possible by varying the antiproton kinetic energy to obtain a suitable annihilation cross section. The annihilation cross section at low energies is …
Date: August 22, 1986
Creator: Morgan, D.L. Jr.
Object Type: Article
System: The UNT Digital Library
Calculation of three-dimensional MHD equilibria with islands and stochastic regions (open access)

Calculation of three-dimensional MHD equilibria with islands and stochastic regions

A three-dimensional MHD equilibrium code is described that does not assume the existence of good surfaces. Given an initial guess for the magnetic field, the code proceeds by calculating the pressure-driven current and then by updating the field using Ampere's law. The numerical algorithm to solve the magnetic differential equation for the pressure-driven current is described, and demonstrated for model fields having islands and stochastic regions. The numerical algorithm which solves Ampere's law in three dimensions is also described. Finally, the convergence of the code is illustrated for a particular stellarator equilibrium with no large islands.
Date: August 1, 1986
Creator: Reiman, A. & Greenside, H.
Object Type: Report
System: The UNT Digital Library
Nuclear alkali metal Rankine power systems for space applications (open access)

Nuclear alkali metal Rankine power systems for space applications

Nucler power systems utilizing alkali metal Rankine power conversion cycles offer the potential for high efficiency, lightweight space power plants. Conceptual design studies are being carried out for both direct and indirect cycle systems for steady state space power applications. A computational model has been developed for calculating the performance, size, and weight of these systems over a wide range of design parameters. The model is described briefly and results from parametric design studies, with descriptions of typical point designs, are presented in this paper.
Date: August 1, 1986
Creator: Moyers, J. C. & Holcomb, R. S.
Object Type: Article
System: The UNT Digital Library
Feasibility of laser pumping with neutron fluxes from present-day large tokamaks (open access)

Feasibility of laser pumping with neutron fluxes from present-day large tokamaks

The minimum fusion-neutron flux needed to observe nuclear-pumped lasing with tokamaks can be reduced substantially by optimizing neutron scattering into the laser cell, located between adjacent toroidal-field coils. The laser lines most readily pumped are probably the /sup 3/He-Ne lines at 0.633 ..mu.. and in the infrared, where the /sup 3/He-Ne gas is excited by energetic ions produced in the /sup 3/He(n,p)T reaction. These lines are expected to lase at the levels of D-T neutron flux foreseen for the TFTR in 1989 (>>10/sup 12/ n/cm/sup 2//s), while amplification should be observable at the existing levels of D-D neutron flux (greater than or equal to 5 x 10/sup 9/ n/cm/sup 2//s). Lasing on the 1.73 ..mu.. and 2.63 ..mu.. transitions of Xe may be observable at the maximum expected levels of D-T neutron flux in TFTR enhanced by scattering.
Date: August 1, 1986
Creator: Jassby, D. L.
Object Type: Report
System: The UNT Digital Library
Plutonium isotopic analysis of highly enriched mixed oxides (open access)

Plutonium isotopic analysis of highly enriched mixed oxides

We investigated the analysis method used by the International Atomic Energy Agency (IAEA) to determine the plutonium isotopic composition of highly enriched mixed oxides (MOX). The IAEA currently uses the Cicero multichannel analyzer and the IAEAPU algorithm for its analysis. In our investigation the plutonium isotopic measurements were found to be good for PuO/sub 2/ powder or low-enriched MOX, but acceptable for highly enriched MOX in IAEA special nuclear material (SNM) accountability applications. The gamma-ray interferences from /sup 235/U resulted in underestimation of the isotopic composition of /sup 239/Pu and overestimation of all other plutonium isotopes. Samples with high /sup 240/Pu content were found to have significantly higher error in plutonium isotopic analyses of highly enriched MOX. Code modifications or use of calibration curves are necessary for plutonium isotopic analyses of highly enriched MOX in IAEA SNM accountability applications.
Date: August 1, 1986
Creator: Clement, S. D. & Augustson, R. H.
Object Type: Report
System: The UNT Digital Library
Theoretical understanding of charm decays (open access)

Theoretical understanding of charm decays

A detailed description of charm decays has emerged. The various concepts involved are sketched. Although this description is quite successful in reproducing the data the chapter on heavy flavour decays is far from closed. Relevant questions like on th real strength of weak annihilation, Penguin operators, etc. are still unanswered. Important directions in future work, both on the experimental and theoretical side are identified.
Date: August 1, 1986
Creator: Bigi, I. I.
Object Type: Article
System: The UNT Digital Library
Time and space dependency of radiative transfer in magnesium (open access)

Time and space dependency of radiative transfer in magnesium

Radiative transfer in a magnesium vapor has been studied. The experimental cell was designed to provide stable density measurements with a ..delta..lambda/sup -2/ variation with respect to the magnesium resonance line, which indicated pure Rayleigh scattering and no evidence of impurities. Total intensity measurements show the radiation field to be highly anisotropic, although somewhat less at late times. 8 refs., 7 figs. (WRF).
Date: August 1, 1986
Creator: Cooper, J.
Object Type: Report
System: The UNT Digital Library
Fermilab Tevatron and Pbar source status report (open access)

Fermilab Tevatron and Pbar source status report

The antiproton production cycle is enumerated, and the commissioning of the antiproton source is described, giving milestones and major obstacles. The Tevatron collider operation is described, including procedure to load the Tevatron with three bunches of protons and three bunches of antiprotons. Commissioning of the Main Ring and Tevatron for collider operation is described. Development and accelerator studies in four areas were necessary: main ring RF manipulations; controls and applications software support; Tevatron storage and low-beta squeeze sequence; and study of various beam transfers, storage steps, and sequences. Final tests are described. A long range upgrade program is presently under evaluation to accomplish these goals: luminosity increase to 5 x 10/sup 31/ cm/sup -2/sec/sup -1/, production rates up to 4 x 10/sup 11/ antiprotons/hr, and intensity increase for fixed target operation. Beam quality is to be improved by the injector and main ring upgrades, and the luminosity goal is addressed by the Collider upgrade. (LEW)
Date: August 1, 1986
Creator: Edwards, H.
Object Type: Article
System: The UNT Digital Library
Physicochemical basis of the Na-K-Ca geothermometer (open access)

Physicochemical basis of the Na-K-Ca geothermometer

Regular changes in solution composition were observed experimentally during granite reaction with dilute NaCl (+CaCl/sub 2/) solutions; these changes closely follow the empirical Na-K-Ca geothermometer relationship. Initial minerals forming the granite (quartz, plagioclase, K-feldspar, and biotite) were etched by the reactions. Alteration phases formed include calcium-zeolite at <300/sup 0/C, feldspar overgrowths at >300/sup 0/C, and minor amounts of clay and calcsilicate at all temperatures. Amphibole overgrowths were also found at 340/sup 0/C. Quartz is near saturation in all experiments, and preliminary calculations of aqueous species distributions and mineral affinities indicate that the solutions achieve super-saturation with feldspars as the temperature increase. A consistent variation attributable to pH differences was observed in the empirical geothermometer relationship for all experimental data. At 340/sup 0/C, the experimental solutions appear to have deviated slightly from the empirical Na-K-Ca relationship. Such deviations may also be found in natural systems that attain such temperatures.
Date: August 1, 1986
Creator: Janecky, D. R.; Charles, R. W.; Bayhurst, Gregory K. & Benjamin, T. M.
Object Type: Report
System: The UNT Digital Library
Convective heat transport in geothermal systems (open access)

Convective heat transport in geothermal systems

Most geothermal systems under exploitation for direct use or electrical power production are of the hydrothermal type, where heat is transferred essentially by convection in the reservoir, conduction being secondary. In geothermal systems, buoyancy effects are generally important, but often the fluid and heat flow patterns are largely controlled by geologic features (e.g., faults, fractures, continuity of layers) and location of recharge and discharge zones. During exploitation, these flow patterns can drastically change in response to pressure and temperature declines, and changes in recharge/discharge patterns. Convective circulation models of several geothermal systems, before and after start of fluid production, are described, with emphasis on different characteristics of the systems and the effects of exploitation on their evolution. Convective heat transport in geothermal fields is discussed, taking into consideration (1) major geologic features; (2) temperature-dependent rock and fluid properties; (3) fracture- versus porous-medium characteristics; (4) single- versus two-phase reservoir systems; and (5) the presence of noncondensible gases.
Date: August 1, 1986
Creator: Lippmann, M.J. & Bodvarsson, G.S.
Object Type: Article
System: The UNT Digital Library
Gaugino masses in superstring inspired models (open access)

Gaugino masses in superstring inspired models

Contributions to the masses of the gauginos in models arising as low energy limits of superstring theories are considered.
Date: August 1, 1986
Creator: Dawson, S.
Object Type: Article
System: The UNT Digital Library
Numerical models for the evaluation of geothermal systems (open access)

Numerical models for the evaluation of geothermal systems

We have carried out detailed simulations of various fields in the USA (Bada, New Mexico; Heber, California); Mexico (Cerro Prieto); Iceland (Krafla); and Kenya (Olkaria). These simulation studies have illustrated the usefulness of numerical models for the overall evaluation of geothermal systems. The methodology for modeling the behavior of geothermal systems, different approaches to geothermal reservoir modeling and how they can be applied in comprehensive evaluation work are discussed.
Date: August 1, 1986
Creator: Bodvarsson, G.S.; Pruess, K. & Lippmann, M.J.
Object Type: Article
System: The UNT Digital Library
Tests of quantum electrodynamics in few-electron very high-Z ions (open access)

Tests of quantum electrodynamics in few-electron very high-Z ions

This article discusses our measurement of the Lamb shift in heliumlike uranium and outlines future tests of QED using few- electron very high atomic number (Z) ions. Our recently reported Lamb shift value of 70.4 (8.1) eV for the one- electron Lamb shift in uranium is in agreement with the theoretical value of 75.3 (0.4) eV. The experimental value was extracted from a beam-foil time-of-flight measurement of the 54.4 (3.3) ps lifetime of the 1s2p/sub 1/2/ /sup 3/P/sub 0/ state of heliumlike uranium. 24 refs., 5 figs., 1 tab.
Date: August 1, 1986
Creator: Gould, H. & Munger, C.T.
Object Type: Article
System: The UNT Digital Library
Applications of the MEVVA high current metal ion source (open access)

Applications of the MEVVA high current metal ion source

A new kind of ion source has been developed in which a metal vapor vacuum arc (MEVVA) is used to produce the plasma from which the ion beam is extracted. The novel and exciting feature of this source is the very high metal ion beam current attainable. A total ion beam current of over 1 Ampere has been extracted from the embodiment of the concept that we're presently using, and this is not a limit of the method. The source was developed to upgrade the uranium ion beam intensity of the Bevatron, LBL's heavy ion synchrotron, for basic nuclear physics research. Other important applications include its use within the Heavy Ion Fusion research effort; for ion implantation; and for other basic research uses. In this paper the source is described briefly, its performance outlined, and its poential and limitations for a variety of applications is discussed.
Date: August 1, 1986
Creator: Brown, I.G.
Object Type: Article
System: The UNT Digital Library
Top quark and light Higgs scalar mass bounds in no-scale supergravity (open access)

Top quark and light Higgs scalar mass bounds in no-scale supergravity

No-scale supergravity theories with the minimal low-energy particle content are shown to become untenable for a top quark mass m/sub T/ much less than 40 GeV. For m/sub T/ < 55 GeV, a stringent upper bound operates on the mass of the lowest-lying Higgs scalar. Further, the Higgs pseudoscalar is constrained to be nearly a quarter as massive as the gluino.
Date: August 29, 1986
Creator: Roy, P.
Object Type: Article
System: The UNT Digital Library
Fabrication and characterization of MCC approved testing material: ATM-11 glass (open access)

Fabrication and characterization of MCC approved testing material: ATM-11 glass

ATM-11 glass is designed to be representative of defense high-level waste glasses that will be produced by the Defense Waste Processing Facility at the Savannah River Plant in Aiken, South Carolina. It is representative of a 300-year-old nuclear waste glass and was intended as a conservative compromise between 10-year-old waste and 1000-year-old waste. The feedstock material for this glass was supplied by Savannah River Laboratory, Aiken, SC, as SRL-165 black frit to which was added Ba, Cs, Mo, Nd, Ni, Pd, Rb, Ru, Sr, Te, Y, and Zr, as well as /sup 241/Am, /sup 237/Np, /sup 239+240/Pu, /sup 151/Sm, /sup 99/Tc, and depleted U. The glass was melted under the reducing conditions that resulted from the addition of 0.7 wt% graphite during the final melting process. Nearly 3 kg of ATM-11 glass were produced from a feedstock melted in a nitrogen-atmosphere glove box at 1250/sup 0/C in Denver Fire Clay crucibles. After final melting, the glass was formed into stress-annealed rectangular bars 1.9 x 1.9 x 10 cm nominal size. Twenty-six bars were cast with a nominal weight of about 100 g each. The analyzed composition of ATM-11 glass is tabulated. Examination of a single transverse section from one bar …
Date: August 1, 1986
Creator: Wald, J. W. & Daniel, J. L.
Object Type: Report
System: The UNT Digital Library
Numerical solution of the Schroedinger integral equation for dt. mu. Progress report (open access)

Numerical solution of the Schroedinger integral equation for dt. mu. Progress report

The Schroedinger Integral Equation is derived for an N-body system, and solutions for required Green's functions are obtained. The initial method of numerical solution has yielded the correct ground states and lower excited states of He (test case) and dt..mu... Steps are being taken to improve the numerical accuracy.
Date: August 22, 1986
Creator: Morgan, D.L. Jr.
Object Type: Report
System: The UNT Digital Library
Measurement of energy deposition near high energy, heavy ion tracks. Progress report, December 1982-April 1985 (open access)

Measurement of energy deposition near high energy, heavy ion tracks. Progress report, December 1982-April 1985

The microscopic spatial distribution of energy deposition in irradiated tissue plays a significant role in the final biological effect produced. Therefore, it is important to have accurate microdosimetric spectra of radiation fields used for radiobiology and radiotherapy. The experiments desribed here were designed to measure the distributions of energy deposition around high energy heavy ion tracks generated at Lawrence Berkeley Laboratory's Bevalac Biomedical Facility. A small proportional counter mounted in a large (0.6 by 2.5 m) vacuum chamber was used to measure energy deposition distributions as a function of the distance between detector and primary ion track. The microdosimetric distributions for a homogeneous radiation field were then calculated by integrating over radial distance. This thesis discusses the rationale of the experimental design and the analysis of measurements on 600 MeV/amu iron tracks. 53 refs., 19 figs.
Date: August 1, 1986
Creator: Metting, N.F.; Braby, L.A.; Rossi, H.H.; Kliauga, P.J.; Howard, J.; Schimmerling, W. et al.
Object Type: Report
System: The UNT Digital Library
A project to improve the capabilities of minorities in energy fields and a cost benefit analysis of an ethyl alcohol plant (open access)

A project to improve the capabilities of minorities in energy fields and a cost benefit analysis of an ethyl alcohol plant

The project being reported in this document had three components: (1) a research project to carry out cost-benefit analysis of an ethyl alcohol plant at Tuskegee University, (2) seminars to improve the high-technology capabilities of minority persons, and (3) a class in energy management. The report provides a background on the three components listed above. The results from the research on the ethyl alcohol plant, are discussed, along with the seminars, and details of the energy management class.
Date: August 1, 1986
Creator: Sara, T.S. & Jones, M. Jr.
Object Type: Report
System: The UNT Digital Library
Ancillary effects of selected acid deposition control policies (open access)

Ancillary effects of selected acid deposition control policies

NAPAP is examining a number of potential ways to reduce the precursors (sulfur dioxide and nitrogen oxides) to acid deposition. However, the policies to reduce acid deposition will have other physical, biological and economic effects unrelated to acid deposition. For example, control policies that reduce sulfur dioxide emissions may also increase visibility. The effects of an acid deposition policy that are unrelated to acid deposition are referred to as ''ancillary'' effects. This reserch identifies and characterizes the principle physical and economic ancillary effects associated with acid deposition control and mitigation policies. In this study the ancillary benefits associated with four specific acid deposition policy options were investigated. The four policy options investigated are: (1) flue gas desulfurization, (2) coal blending or switching, (3) reductions in automobile emissions of NO/sub x/, and (4) lake liming. Potential ancillary benefits of each option were identified and characterized. Particular attention was paid to the literature on economic valuation of potential ancillary effects.
Date: August 1, 1986
Creator: Moe, R.J.; Lyke, A. J. & Nesse, R. J.
Object Type: Report
System: The UNT Digital Library
Program report for FY 1984 and 1985 Atmospheric and Geophysical Sciences Division of the Physics Department (open access)

Program report for FY 1984 and 1985 Atmospheric and Geophysical Sciences Division of the Physics Department

This annual report for the Atmospheric and Geophysical Sciences Division (G-Division) summarizes the activities and highlights of the past three years, with emphasis on significant research findings in two major program areas: the Atmospheric Release Advisory Capability (ARAC), with its recent involvement in assessing the effects of the Chernobyl reactor accident, and new findings on the environmental consequences of nuclear war. The technical highlights of the many other research projects are also briefly reported, along with the Division's organization, budget, and publications.
Date: August 1, 1986
Creator: Knox, J. B.; MacCracken, M. C.; Dickerson, M. H.; Gresho, P. M. & Luther, F. M.
Object Type: Report
System: The UNT Digital Library
Analysis of fuel shares in the residential sector: 1960 to 1995 (open access)

Analysis of fuel shares in the residential sector: 1960 to 1995

Historical and future energy use by fuel type in the residential sector of the United States are examined. Of interest is the likely relative demand for fuels as they affect national policy issues such as the potential shortfall of electric generating capacity in the mid to late 1990's and the ability of the residential sector to switch rapdily among fuels in response to fuel shortages, price increases and other factors. Factors affecting the share of a fuel used rather than the aggregate level of energy use are studied. However, the share of a fuel used is not independent of the level of energy consumption. In the analysis, the level of consumption of each fuel is computed as an intermediate result and is reported for completeness.
Date: August 1, 1986
Creator: Reilly, J.M.; Shankle, S.A. & Pomykala, J.S.
Object Type: Report
System: The UNT Digital Library