Calculated cross sections for production and destruction of some long-lived nuclides of importance in fusion energy applications (open access)

Calculated cross sections for production and destruction of some long-lived nuclides of importance in fusion energy applications

Knowledge of the production and destruction of long-lived species via neutrons, photons, and charged-particles is required in many fusion energy applications, such as reactor first-wall and blanket design, radioactive waste management, etc. Here we describe our calculational results for the production, via the (n,2n) reaction, of the following long-lived species: {sup 150}Eu(t{sub 1/2} = 36 y), {sup 152}Eu(t{sub 1/2} = 13 y), and {sup 192m2}Ir(t{sub 1/2} = 241 y). Some comments on calculations that we`ve made for destruction reactions of these species are also included.
Date: July 8, 1993
Creator: Gardner, M. A. & Gardner, D. G.
System: The UNT Digital Library
Comparison of the folded stripline and stacked stripline concepts to the folded waveguide launcher (open access)

Comparison of the folded stripline and stacked stripline concepts to the folded waveguide launcher

Two new concepts are being developed as possible upgrades to the folded waveguide launcher. The folded stripline is a folded waveguide with an additional conductor positioned inside. The term stripline refers to the resemblance of the design to microwave microstrip line. The conductor provides support for TEM mode propagation, which eliminates cutoff and the nonlinear frequency dependence of the waveguide impedance and phase velocity. A natural extension to the folded stripline is the stacked stripline, which comprises several stacked, independent TEM waveguides. Initial measurements indicate that both concepts have better magnetic flux coupling than the folded waveguide.
Date: December 31, 1993
Creator: Gardner, W. L.; Caughman, J. B. O.; Hoffman, D. J. & Probert, P. H.
System: The UNT Digital Library
Indium donor complexes with cation vacancies in CdTe and ZnSe (open access)

Indium donor complexes with cation vacancies in CdTe and ZnSe

Very dilute (10{sub 12} cm{sup {minus}3}) indium donors in CdTe and ZnSe powders and in CdTe single crystals were investigated using {sup 111}In Perturbed angular correlation spectroscopy. Most indium atoms are in uncomplexed sites but can form weakly-bound complexes with native defects in very defective material. The only complex observed in CdTe is an indium-Cd vacancy pair. The CdTe in which these pairs occur is apparently n-type, most Cd vacancies are free and doubly-charged, and the binding energy with indium is 0.15 eV. In ZnSe, indium can pair with a Zn vacancy or with some other presently unidentified defect. These complexes form in ZnSe containing large concentrations of both free Zn vacancies and complexes of Zn vacancies with other defects. In CdTe, the pair formation equilibration time constant is two days at 15C,an implication that Cd vacancies are mobile at room temperature. Lattice relaxation around a Cd vacancy in CdTe was probed by single crystal PAC experiments.
Date: November 1, 1993
Creator: Griffith, J. W.; Lundquist, R.; Platzer, R.; Gardner, J. A.; Karczewski, G. & Furdyna, J. K.
System: The UNT Digital Library
Intercomparison of theoretical calculations of important activation cross sections for fusion reactor technology (open access)

Intercomparison of theoretical calculations of important activation cross sections for fusion reactor technology

Various theoretical calculations of radionuclides in the reactions {sup 94}Mo(n,p){sup 94}Nb, {sup 109}Ag(n,2n){sup 108m}Ag, {sup 151}Eu(n,2n){sup 150m}Eu, {sup 153}Eu(n,2n){sup 152g+m2}Eu, {sup 159}Tb(n,2n){sup 158}Tb, {sup 187}Re(n,2n){sup 186m}Re, {sup 179}Hf(n,2n){sup l78m2}Hf, {sup 193}Ir(n,2n){sup 192m2}Ir are compared. We normalize the theoretical results to the evaluated experimental data at 14.5 MeV, and take their average. This yields averaged theoretical excitation functions for the production of the various radionuclides at neutron energies ranging from threshold to 14.5 MeV. We discuss differences between the various theoretical results, and between theory and data where they exist. Our theoretical results may be used in conjunction with experimental data to produce evaluated radionuclide production cross sections for neutron energies lower than 14.5 MeV.
Date: November 1, 1993
Creator: Chadwick, M. B.; Gardner, M.; Gardner, D.; Grudzevich, O. T.; Ignatyuk, A. V.; Meadows, J. W. et al.
System: The UNT Digital Library
Harmonic analysis of the AGS Booster imperfection (open access)

Harmonic analysis of the AGS Booster imperfection

The harmonic content of magnetic field imperfections in the AGS Booster has been determined through careful measurements of the required field corrections of transverse resonances. An analysis of the required correction yielded amplitude and phase information which points to possible sources of imperfections. Dipole and quadrupole imperfections, which are proportional to the field of bending magnets (B), are mainly driven by any misalignment of the magnets. Quadrupole and sextupole imperfections, which are proportional to dB/dt, are driven by imperfections of the eddy-current correction system. The observations also suggest the presence of a remnant field.
Date: December 31, 1993
Creator: Shoji, Y. & Gardner, C.
System: The UNT Digital Library
On the high intensity aspects of AGS Booster proton operation (open access)

On the high intensity aspects of AGS Booster proton operation

Observations of high intensity effects on the proton performance of the AGS Booster are presented, including present operational limits and correction methods. The transverse emittances, optimum tune working points, damping of coherent transverse oscillations and correction of stopband resonances through third-order are discussed in addition to the observed tune spread due to space charge forces. The initial longitudinal phase space distribution, capture and acceleration parameters and measurements are also given. Operational tools and strategies relevant to the high intensity setup are mentioned.
Date: January 1, 1993
Creator: Reece, R. K.; Ahrens, L. A.; Bleser, E. J.; Brennan, J. M.; Gardner, C.; Glenn, J. W. et al.
System: The UNT Digital Library
On the high intensity aspects of AGS Booster proton operation (open access)

On the high intensity aspects of AGS Booster proton operation

Observations of high intensity effects on the proton performance of the AGS Booster are presented, including present operational limits and correction methods. The transverse emittances, optimum tune working points, damping of coherent transverse oscillations and correction of stopband resonances through third-order are discussed in addition to the observed tune spread due to space charge forces. The initial longitudinal phase space distribution, capture and acceleration parameters and measurements are also given. Operational tools and strategies relevant to the high intensity setup are mentioned.
Date: June 1, 1993
Creator: Reece, R. K.; Ahrens, L. A.; Bleser, E. J.; Brennan, J. M.; Gardner, C.; Glenn, J. W. et al.
System: The UNT Digital Library
The reaction of hydroperoxy-propyl radicals with molecular oxygen (open access)

The reaction of hydroperoxy-propyl radicals with molecular oxygen

Addition of hydroperoxy-alkyl radicals to molecular oxygen leads to chain branching in autoignition and engine knock, and in low temperature oxidation of paraffins. Rate constants and product channels for reaction of hydroperoxy-propyl radicals with O{sub 2} are estimated using thermodynamic properties, bimolecular quantum Kassel analysis and transition state theory. Thermochemistry of relevant molecules and radicals is estimated using group additivity and bond dissociation groups for radicals. Results show that rates of the hydroperoxy-propyl radical addition to O{sub 2} are near their high pressure limits at {ge} 1 atm. Main products at 1--15 atm are stabilization, reverse reaction to hydroperoxy-propyl + O{sub 2} and alkyl carbonyl + OH. Reactions of the stabilized adducts, dissociation rates and product channels are estimated using unimolecular quantum Kassel analysis, because stabilization is the most important hydroperoxy-propyl radical + O{sub 2} product channel. Below 700 K, the stabilized peroxy adducts react primarily to hydroperoxy-carbonyl + OH, products which lead to chain branching. Above 700K, the stabilized peroxy adducts react primarily to hydroperoxy-propyl radical + O{sub 2}, initial reactants, which inhibits the overall oxidation. This switchover in channels correlates well observed negative temperature coefficient behavior for propane oxidation. Rate expressions for reaction of each of the three …
Date: December 3, 1993
Creator: Bozzelli, J. W. & Pitz, W. J.
System: The UNT Digital Library
Observation and correction of resonance stopbands in the AGS Booster (open access)

Observation and correction of resonance stopbands in the AGS Booster

At the design intensity of 1.5 {times} 10{sup 13} ppp, the space charge tune shift in the AGS Booster at injection has been estimated to be about 0.35. Therefore, the beam is spread over may lower order resonance lines and the stopbands have to be corrected to minimize the amplitude growth by proper compensation of the driving harmonics resulting from random errors. The observation and correction of second and third order resonance stopbands in the AGS Booster, and the establishment of a favorable operating point at high intensity are discussed.
Date: June 1, 1993
Creator: Gardner, C.; Shoji, Y.; Ahrens, L.; Glenn, J. W.; Lee, Y. Y.; Roser, T. et al.
System: The UNT Digital Library
A standardized approach for determining radiological sabotage targets (open access)

A standardized approach for determining radiological sabotage targets

The US Department of Energy has required radiological sabotage vulnerability assessments to be conducted for years. However, the exact methodology to be used in this type of analysis still remains somewhat elusive. Therefore, there is tremendous variation in the methodologies and assumptions used to determine release levels and doses potentially affecting the health and safety of the public. In some cases, there are three orders of magnitude difference in results for dispersal of similar materials under similar meteorological conditions. To address this issue, the authors have developed an approach to standardizing radiological sabotage target analysis that starts by addressing basic assumptions and then directs the user to some recommended computerized analytical tools. Results from different dispersal codes are also compared in this analysis.
Date: July 1, 1993
Creator: Gardner, B. H. & Snell, M. K.
System: The UNT Digital Library
The Instructor-Free Training Department (open access)

The Instructor-Free Training Department

Today`s skills will be obsolete in the year 2000. That workforce will require a much higher degree of technical sophistication and adaptability. Enormous demands will be made of DOE contractor training departments even as federal deficit reduction actions increasingly restrict resources and as the emergence of electronic performance support systems appear to diminish the need for training. True training will still be required but they must, and can, train better, faster, and cheaper. These goals are attainable by implementing the implications of performance-based training and by focusing on learning instead of on teaching. (Indeed, ability to learn efficiently and rapidly will be the premier talent in the next century.) Training Departments must dedicate themselves to changing performance, not to teaching classes. The best training department of the future will have no {open_quotes}instructors{close_quotes}. Trainingforce 2000 will look and function much differently.
Date: November 1, 1993
Creator: Gardner, P. R. & Sanford, D. E.
System: The UNT Digital Library
MIMD massively parallel methods for engineering and science problems (open access)

MIMD massively parallel methods for engineering and science problems

MIMD massively parallel computers promise unique power and flexibility for engineering and scientific simulations. In this paper we review the development of a number of software methods and algorithms for scientific and engineering problems which are helping to realize that promise. We discuss new domain decomposition, load balancing, data layout and communications methods applicable to simulations in a broad range of technical field including signal processing, multi-dimensional structural and fluid mechanics, materials science, and chemical and biological systems.
Date: August 1, 1993
Creator: Camp, W. J. & Plimpton, S. J.
System: The UNT Digital Library
A survey of metallurgical research on several actinides (open access)

A survey of metallurgical research on several actinides

A Los Alamos perspective on metallurgical research on neptunium, plutonium, americium, curium, and californium is presented. Alloying behaviors of these metals are discussed. Metal fabrication technologies, principally for plutonium, are emphasized.
Date: November 1, 1993
Creator: Olivas, J. D. & Schonfeld, F. W.
System: The UNT Digital Library
Eighteenth workshop on geothermal reservoir engineering: Proceedings (open access)

Eighteenth workshop on geothermal reservoir engineering: Proceedings

PREFACE The Eighteenth Workshop on Geothermal Reservoir Engineering was held at Stanford University on January 26-28, 1993. There were one hundred and seventeen registered participants which was greater than the attendance last year. Participants were from eight foreign countries: Italy, Japan, United Kingdom, Mexico, New Zealand, the Philippines, Guatemala, and Iceland. Performance of many geothermal fields outside the United States was described in several of the papers. Dean Gary Ernst opened the meeting and welcomed the visitors to the campus. The key note speaker was J.E. ''Ted'' Mock who gave a brief overview of the Department of Energy's current plan. The Stanford Geothermal Program Reservoir Engineering Award for Excellence in Development of Geothermal Energy was awarded to Dr. Mock who also spoke at the banquet. Thirty-nine papers were presented at the Workshop with two papers submitted for publication only. Technical papers were organized in twelve sessions concerning: field operations, The Geysers, geoscience, hot-dry-rock, injection, modeling, slim hole wells, geochemistry, well test and wellbore. Session chairmen were major contributors to the program and we thank: John Counsil, Kathleen Enedy, Harry Olson, Eduardo Iglesias, Marcelo Lippmann, Paul Atkinson, Jim Lovekin, Marshall Reed, Antonio Correa, and David Faulder. The Workshop was organized by …
Date: January 28, 1993
Creator: Ramey, H.J., Jr.; Horne, R.J.; Kruger, P.; Miller, F. G.; Brigham, W. E. & Cook, J. W.
System: The UNT Digital Library
Prototype explosives detection system based on nuclear resonance absorption in nitrogen (open access)

Prototype explosives detection system based on nuclear resonance absorption in nitrogen

A-prototype explosives detection system that was developed for experimental evaluation of a nuclear resonance absorption techniques is described. The major subsystems are a proton accelerator and beam transport, high-temperature proton target, an airline-luggage tomographic inspection station, and an image-processing/detection- alarm subsystem. The detection system performance, based on a limited experimental test, is reported.
Date: December 1, 1993
Creator: Morgado, R. E.; Arnone, G.; Cappiello, C. C.; Gardner, S. D.; Hollas, C. L.; Ussery, L. E. et al.
System: The UNT Digital Library
Eddy current control in the AGS rapid cycling booster accelerator magnets (open access)

Eddy current control in the AGS rapid cycling booster accelerator magnets

The Booster requires highly variable magnet cycles. When B is large, eddy current induced sextupole, etc., in the dipole vacuum chamber (VC) is large, with a much smaller contribution from magnet ends. Simple passive coils excited automatically by transformer action cancel the B induced sextupole. A self correction coil is not required for the quadrupoles, since g induced aberrations are very small (< 1.0 {times} 10{sup {minus}4} at full aperture). Iron magnetization does not produce dipole or quadrupole magnet multipole aberrations, so these magnets have been effectively made independent of unwanted multipoles for all cycles. However, variations in the transfer functions and thus the Booster tune have not been automatically eliminated. Iron magnetization contributions are almost matched, but the B induced field retardation in the dipoles VC is larger than in the quadrupoles. Results of measurements will be presented, plus a simple system to overcome the mismatch and make the tune independent of B. Properties of special lattice magnets and their corrections will also be described.
Date: November 1, 1993
Creator: Danby, G. T.; Jackson, J. W. & Spataro, C.
System: The UNT Digital Library
A review of the ablative stabilization of the Rayleigh-Taylor instability in regimes relevant to Inertial Confinement Region. Revision 1 (open access)

A review of the ablative stabilization of the Rayleigh-Taylor instability in regimes relevant to Inertial Confinement Region. Revision 1

It has been recognized for many year`s that the most significant limitation of ICF is the Rayleigh-Taylor (R-T) instability. It limits the distance an ablatively driven shell can be moved to several times its initial thickness. Fortunately material flow through the unstable region at velocity v{sub A} reduces the growth rate to {radical}{sub 1+kL}/{sup kg} {minus}{beta}kv{sub A} with {beta} from 2-3. In recent years experiments using both x-ray drive and smoothed laser drive to accelerate foils have confirmed our understanding of the ablative R-T instability in planar geometry. The growth of small initial modulations on the foils is measured for growth factors up to 60 for direct drive and 80 for indirect drive. For x-ray drive large stabilization is evident. After some growth, the instability enters the non-linear phase when mode coupling and saturation are also seen and compare well with modeling. Normalized growth rates for direct drive are measured to be higher, but strategies for reduction by raising the isentrope are being investigated. For direct drive, high spatial frequencies are imprinted from the laser beam and amplified by the R-T instability. Modeling shows an understanding of this ``laser imprinting.``
Date: December 1, 1993
Creator: Kilkenny, J. D.; Glendinning, S. G. & Haan, S. W.
System: The UNT Digital Library
Oxygen sparging of residue salts (open access)

Oxygen sparging of residue salts

Oxygen sparge is a process for treating salt residues at Los Alamos National Laboratory by sparging oxygen through molten salts. Oxygen reacts with the plutonium trichloride in these salts to form plutonium dioxide. There is further reaction of the plutonium dioxide with plutonium metal and the molten salt to form plutonium oxychloride. Both of the oxide plutonium species are insoluble in the salt and collect atthe bottom of the crucible. This results in a decrease of a factor of 2--3 in the amount of salt that must be treated, and the amount of waste generated by aqueous treatment methods.
Date: March 1, 1993
Creator: Garcia, E.; Griego, W. J.; Owens, S. D.; Thorn, C. W. & Vigil, R. A.
System: The UNT Digital Library
Oxygen sparging of residue salts (open access)

Oxygen sparging of residue salts

Oxygen sparge is a process for treating salt residues at Los Alamos National Laboratory by sparging oxygen through molten salts. Oxygen reacts with the plutonium trichloride in these salts to form plutonium dioxide. There is further reaction of the plutonium dioxide with plutonium metal and the molten salt to form plutonium oxychloride. Both of the oxide plutonium species are insoluble in the salt and collect atthe bottom of the crucible. This results in a decrease of a factor of 2--3 in the amount of salt that must be treated, and the amount of waste generated by aqueous treatment methods.
Date: January 1, 1993
Creator: Garcia, E.; Griego, W.J.; Owens, S.D.; Thorn, C.W. & Vigil, R.A.
System: The UNT Digital Library
Laser driven hydrodynamic instability experiments. Revision 1 (open access)

Laser driven hydrodynamic instability experiments. Revision 1

An extensive series of experiments has been conducted on the Nova laser to measure hydrodynamic instabilities in planar foils accelerated by x-ray ablation. Single mode experiments allow a measurement of the fundamental growth rates from the linear well into the nonlinear regime. Two-mode foils allow a first direct observation of mode coupling. Surface-finish experiments allow a measurement of the evolution of a broad spectrum of random initial modes.
Date: February 17, 1993
Creator: Remington, B. A.; Weber, S. V.; Haan, S. W.; Kilkenny, J. D.; Glendinning, S. G.; Wallace, R. J. et al.
System: The UNT Digital Library
A superconducting short period undulator for a harmonic generation FEL experiment (open access)

A superconducting short period undulator for a harmonic generation FEL experiment

A three stage superconducting (SC) undulator for a high gain harmonic generation (HGE) FEL experiment in the infrared is under construction at the NSLS in collaboration with Grumman Corporation. A novel undulator technology suitable for short period (6--40mm) undulators will be employed for all three stages, the modulator, the dispersive section and the radiator. The undulator triples the frequency of a 10.4{mu}m CO{sub 2} seed laser. So far a 27 period (one third of the final radiator) prototype radiator has been designed, built and tested.
Date: July 1, 1993
Creator: Ingold, G.; Solomon, L.; Ben-Zvi, Ilan; Krinsky, S.; Li, D.; Lynch, D. et al.
System: The UNT Digital Library
Monte Carlo simulations of plutonium gamma-ray spectra (open access)

Monte Carlo simulations of plutonium gamma-ray spectra

Monte Carlo calculations were investigated as a means of simulating the gamma-ray spectra of Pu. These simulated spectra will be used to develop and evaluate gamma-ray analysis techniques for various nondestructive measurements. Simulated spectra of calculational standards can be used for code intercomparisons, to understand systematic biases and to estimate minimum detection levels of existing and proposed nondestructive analysis instruments. The capability to simulate gamma-ray spectra from HPGe detectors could significantly reduce the costs of preparing large numbers of real reference materials. MCNP was used for the Monte Carlo transport of the photons. Results from the MCNP calculations were folded in with a detector response function for a realistic spectrum. Plutonium spectrum peaks were produced with Lorentzian shapes, for the x-rays, and Gaussian distributions. The MGA code determined the Pu isotopes and specific power of this calculated spectrum and compared it to a similar analysis on a measured spectrum.
Date: July 16, 1993
Creator: Koenig, Z. M.; Carlson, J. B.; Wang, Tzu-Fang & Ruhter, W. D.
System: The UNT Digital Library
A 12-channel VMEbus-based pulse-height analysis module (open access)

A 12-channel VMEbus-based pulse-height analysis module

The author describes a 12-channel VMEbus-based pulse-height analysis board that was designed for use in a high-rate, multidetector, gamma-ray imaging system. This module was designed to minimize dead-time losses and to allow all key parameters to be software controlled. Gamma-ray detectors are connected directly to this module, eliminating the need for additional electronics.
Date: December 1, 1993
Creator: Arnone, G. J.
System: The UNT Digital Library
Proceedings of the IMOG (Interagency Manufacturing Operations Group) Numerical Systems Group. 62nd Meeting (open access)

Proceedings of the IMOG (Interagency Manufacturing Operations Group) Numerical Systems Group. 62nd Meeting

This document contains the proceedings of the 62nd Interagency Manufacturing Operations Group (IMOG) Numerical Systems Group. Included are the minutes of the 61st meeting and the agenda for the 62nd meeting. Presentations at the meeting are provided in the appendices to this document. Presentations were: 1992 NSG Annual Report to IMOG Steering Committee; Charter for the IMOG Numerical Systems Group; Y-12 Coordinate Measuring Machine Training Project; IBH NC Controller; Automatically Programmed Metrology Update; Certification of Anvil-5000 for Production Use at the Y-12 Plant; Accord Project; Sandia National Laboratories {open_quotes}Accord{close_quotes}; Demo/Anvil Tool Path Generation 5-Axis; Demo/Video Machine/Robot Animation Dynamics; Demo/Certification of Anvil Tool Path Generation; Tour of the M-60 Inspection Machine; Distributed Numerical Control Certification; Spline Usage Method; Y-12 NC Engineering Status; and Y-12 Manufacturing CAD Systems.
Date: October 1, 1993
Creator: Maes, G. J.
System: The UNT Digital Library