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in publisher: "Oak Ridge National Lab., TN USA"

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mu. - and tau-pair production from relativistic heavy-ion collisions

The question is addressed of ..mu..- and tau-pair production from the motional Coulomb fields available at the new relativistic heavy-ion accelerators. A semiclassical field theory is developed which is appropriate for families of leptons which are coupled electromagnetically. The field equations are mapped on to a lattice of collocation points using basis spline methods, and techniques for solving the resulting lattice equations are outlined. The properties of the transverse electromagnetic fi… more

Date: January 1, 1986

Creator: Bottcher, C. & Strayer, M. R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Possibility of New Particle Production in Heavy-Ion Collisions

Two-body decay of a particle is hypothesized in order to explain the lack of strong Z dependence of positron emission spectra in low-energy heavy ion collisions. The consequences of such a hypothesis are discussed, as well as recent theoretical and experimental work motivated by it. 50 refs. (LEW)

Date: January 1, 1986

Creator: Balantekin, A. B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Crystal blocking in heavy ion reactions

The crystal blocking technique, used to measure very short lifetime (10/sup -18/ sec), was developed during the 1960's primarily in connection with the study of the channeling effect. Early blocking lifetime measurements involved light ion resonance reactions yielding typical lifetime values down to the order of 10/sup -17/ sec. Recently, studies of heavy-ion induced fission and fusion have extended the technique into the 10/sup -18/ to 10/sup -19/ sec scale. In this work measurements of fusion… more

Date: January 1, 1986

Creator: del Campo, J.G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Pair production at GeV/u energies

Electron and positron production in relativistic ion-atom collisions is discussed within the context of the time-dependent Dirac-Hartree approximation to a fully relativistic field theory of the collision. The time-dependent fields are treated classically, and the numerical methods employing basis splines are discussed in detail and contrasted with results obtained from the case of non-relativistic velocities. The results of a one-dimensional model are presented and show a moderately large prob… more

Date: January 1, 1985

Creator: Bottcher, C. & Strayer, M. R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Radiation effects in space

The paper discusses the radiation environment in space that astronauts are likely to be exposed to. Emphasis is on proton and HZE particle effects. Recommendations for radiation protection guidelines are presented. (ACR)

Date: January 1, 1986

Creator: Fry, R.J.M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Fabrication of three 2500-watt (thermal) strontium-90 heat sources

Three 2500-watt (thermal) heat sources were fabricated by the Oak Ridge National Laboratory (ORNL) for the purpose of fueling a 500-watt (electric) thermoelectric generator as part of the US Department of Energy's Byproducts Utilization Program (BUP). Each of the sources, which are the largest ever assembled, consist of hot-pressed pellets of /sup 90/Sr fluoride, doubly encapsulated in three Haynes-25 inner capsules and in a Hastelloy-S outer capsule. The total /sup 90/Sr inventory of all three… more

Date: August 1, 1986

Creator: DeVore, J. R.; Haff, K. W. & Tompkins, J. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Characterization of radiological emergencies

Several severe radiological emergencies were reviewed to determine the likely range of conditions which must be coped with by a mobile teleoperator designed for emergencies. The events reviewed included accidents at TMI (1978), SL-1 (1961), Y-12 (1958), Bethesda (1982), Chalk River (1952 and 1958), Lucens (1969). The important conditions were: radiation fields over 10,000 R/h, severe contamination, possible critical excursion, possible inert atmosphere, temperatures from 50/sup 0/C to -20/sup 0… more

Date: January 1, 1985

Creator: Chester, C. V.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Demonstrations of safeguards process monitoring sensitivities. Consolidated Fuel Reprocessing Program

Can process-monitoring information be incorporated into safeguards tests. What level of sensitivity to removals of materials can be achieved with process monitoring tests. These questions are being answered by a series of tests in US facilities. These tests involve full-scale facilities that simulate operating reprocessing plant conditions with natural or depleted uranium solutions as surrogate feed materials. Safeguards systems are in place to detect loss or unauthorized removals of solutions.… more

Date: September 1, 1986

Creator: Ehinger, M.H. & Wachter, J.W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Tensile and fracture properties of EBR-II-irradiated V-15Cr-5Ti containing helium

The alloy V-15Cr-5Ti was cyclotron-implanted with 80 appM He and subsequently irradiated in the Experimental Breeder Reactor (EBR-II) to 30 dpa. The same alloy was also irradiated in the 10, 20, and 30% cold-worked conditions. Irradiation temperatures ranged from 400 to 700/sup 0/C. No significant effects of helium on mechanical properties were found in this temperature range although the neutron irradiation shifted the temperature of transition from cleavage to ductile fracture to about 625/su… more

Date: January 1, 1986

Creator: Grossbeck, M.L. & Horak, J.A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Large coil task and results of testing US coils

The United States, EURATOM, Japan, and Switzerland have collaborated since 1978 in development of superconducting toroidal field coils for fusion reactor applications. The United States provided a test facility nd three coils; the other participants, one coil each. All coils have the same interface dimensions and performance requirements (stable at 8 T), but internal design was decided by each team. Two US coil teams chose bath-cooled NbTi, 10-kA conductors. One developed a Nb/sub 3/Sn conducto… more

Date: January 1, 1986

Creator: Haubenreich, P.N.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Scoping study of casks shipped from the MRS facility to various repository sites

The objective of this study was to determine the maximum number of specialized repository waste packages that could be shipped from the Monitored Retrievable Storage (MRS) facility in Pb-, Fe-, and U-shielded casks weighing 200,000 or 300,000 lbs. The study included 18 different waste packages designed for the Salt, Tuff, and Basalt repositories. Nine of these contained consolidated PWR fuel pins, and nine contained consolidated BWR fuel pins. Discrete ordinates calculations were performed to d… more

Date: August 1, 1986

Creator: Bucholz, J.A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Early history of neutron scattering at Oak Ridge

Most of the early development of neutron scattering techniques utilizing reactor neutrons occurred at the Oak Ridge National Laboratory during the years immediately following World War II. C.G. Shull, E.O. Wollan, and their associates systematically established neutron diffraction as a quantitative research tool and then applied this technique to important problems in nuclear physics, chemical crystallography, and magnetism. This article briefly summarizes the very important research at ORNL du… more

Date: July 1, 1985

Creator: Wilkinson, M.K.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Solid State Division Progress Report for period ending March 31, 1986

This report is divided into: theoretical solid-state physics, surface and near-surface properties of solids, defects in solids, transport properties of solids, neutron scattering, and synthesis and properties of novel materials. (DLC)

Date: August 1, 1986

Creator: Green, P. H. & Watson, D. M. (eds.)

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Resin bead methodology as applied to fuel burn-up and fissile inventories

A new technique has been developed that allows acquisition of samples from matrices difficult to access. While the examples given in this paper are from the nuclear field, the technique is readily modified to address other areas. The technique involves obtaining samples on resin beads; each bead then comprises a sample for mass spectrometric analysis. Through the application of isotope dilution, concentrations of the target elements can be obtained in addition to their isotopic compositions. Ex… more

Date: January 1, 1986

Creator: Smith, D. H.; Walker, R. L. & Carter, J. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Vacuum ultraviolet light generation applications to resonance ionization spectroscopy

A theoretical discussion is given for sum mixing with unfocused Gaussian beams. The four-wave sum and difference mixing are carried out in two ''active'' gases: xenon and krypton. In the negatively dispersive regions buffer gases are added to achieve phase matching. 6 refs., 2 figs. (WRF)

Date: August 1, 1986

Creator: Payne, M.G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Release and transport of fission product cesium in the TMI-2 accident

Approximately 50% of the fission product cesium was released from the overheated UO/sub 2/ fuel in the TMI-2 accident. Steam that boiled away from a water pool in the bottom of the reactor vessel transported the released fission products throughout the reactor coolant system (RCS). Some fission products passed directly through a leaking valve with steam and water into the containment structure, but most deposited on dry surfaces inside of the RCS before being dissolved or resuspended when the R… more

Date: January 1, 1986

Creator: Lorenz, R. A. & Collins, J. L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Void-precipitate association during neutron irradiation of austenitic stainless steel

Microstructural data has recently become available on a single heat of 316 stainless steel irradiated in EBR-II and HFIR, over a wide range of irradiation temperature (55 to 750/sup 0/C), dose (7 to 75 dpa), and helium generation rate (0.5 to 55 at. ppM He/dpa). Extensive information on precipitate compositions and characteristics are included. The data reveal several important relationships between the development of voids and precipitation. Precipitate associated voids dominate the swelling o… more

Date: January 1, 1986

Creator: Pedraza, D. F. & Maziasz, P. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Multicode comparison of selected source-term computer codes

This report summarizes the results of a study to assess the predictive capabilities of three radionuclide inventory/depletion computer codes, ORIGEN2, ORIGEN-S, and CINDER-2. The task was accomplished through a series of comparisons of their output for several light-water reactor (LWR) models (i.e., verification). Of the five cases chosen, two modeled typical boiling-water reactors (BWR) at burnups of 27.5 and 40 GWd/MTU and two represented typical pressurized-water reactors (PWR) at burnups of… more

Date: April 1, 1989

Creator: Hermann, O.W.; Parks, C.V.; Renier, J.P.; Roddy, J.W.; Ashline, R.C.; Wilson, W.B. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Strategy for conducting environmental surveillance of groundwater to comply with DOE orders

This document defines the strategy for conducting environmental surveillance of groundwater quality at Department of Energy (DOE) installations as it will be implemented by Martin Marietta Energy Systems, Inc. The primary objectives of defining this generic strategy prior to developing site-specific plans are to: clearly differentiate between effluent monitoring and environmental surveillance as they apply to groundwater, describe the principles and concepts of groundwater flow that must be con… more

Date: December 1, 1990

Creator: Forstrom, J.M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

High-throughput continuous cryopump

A cryopump with a unique method of regeneration which allows continuous operation at high throughput has been constructed and tested. Deuterium was pumped continuously at a throughput of 30 Torr.L/s at a speed of 2000 L/s and a compression ratio of 200. Argon was pumped at a throughput of 60 Torr.L/s at a speed of 1275 L/s. To produce continuous operation of the pump, a method of regeneration that does not thermally cycle the pump is employed. A small chamber (the ''snail'') passes over the pum… more

Date: January 1, 1986

Creator: Foster, C. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Pretest aerosol code comparisons for LWR aerosol containment tests LA1 and LA2

The Light-Water-Reactor (LWR) Aerosol Containment Experiments (LACE) are being performed in Richland, Washington, at the Hanford Engineering Development Laboratory (HEDL) under the leadership of an international project board and the Electric Power Research Institute. These tests have two objectives: (1) to investigate, at large scale, the inherent aerosol retention behavior in LWR containments under simulated severe accident conditions, and (2) to provide an experimental data base for validati… more

Date: January 1, 1986

Creator: Wright, A. L.; Wilson, J. H. & Arwood, P. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Mechanical Property Measurements on Ion-Irradiated Metals

A recently developed mechanical properties microprobe (MPM) has been used to investigate strength and elastic modulus changes in ion-irradiated metals. The indenter load and its displacement are simultaneously monitored while the indentation is being made and also during unloading. Microindentation hardness measurements have been performed on ion-irradiated copper and Cu-0.15% Zr (AMZIRC). The depth dependence of the ion damage has been investigated in selected specimens which were prepared usi… more

Date: August 1, 1986

Creator: Zinkle, S. J. & Oliver, W. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

An interim report on the materials and selection criteria analysis for the Compact Ignition Tokamak toroidal field coil turn-to-turn insulation system

This document contains photographs showing the results of laboratory testing of the combinations of epoxy resins, hardeners, and cures undertaken as part of the Compact Ignition Tokamak Insulation Screening Program. Cryogenic shock and soak to equilibrium proved to be the most demanding condition for these materials. The degree of damage to the basic materials when a poor candidate is selected is shown to be quite dramatic. 34 figs.

Date: January 1, 1990

Creator: Campbell, V. W.; Dooley, J. B.; Hubrig, J. G.; Janke, C. J.; McManamy, T. J. & Welch, D. E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Low-temperature phosphor thermometry: Calibration of europium-doped lanthanum oxysulfide between room temperature and minus 194 degrees C

Remote-temperature measurements can be accomplished by inducing fluorescence in doped phosphors and measuring emission lifetimes. Some phosphors have been calibrated for high temperature measurement from room temperature to about 1200{degree}C and are proving useful where remote sensing is require. Attention is now turned to remote thermal sensing at low-temperature ranges. Because is has strong emission spectra at low temperatures, as well as relatively high temperatures, lanthanum oxysulfide … more

Date: February 1, 1990

Creator: Simmons, C. M.; Beshears, D. L. & Cates, M. R.

Item Type: Report

Partner: UNT Libraries Government Documents Department