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A HIGH-RESOLUTION HIGH-LUMINOSITY BETA-RAY SPECTROMETER DESIGN EMPLOYING AZIMUTHALLY VARYING MAGNETIC FIELDS (open access)

A HIGH-RESOLUTION HIGH-LUMINOSITY BETA-RAY SPECTROMETER DESIGN EMPLOYING AZIMUTHALLY VARYING MAGNETIC FIELDS

A double-focusing magnetic field for a spectrometer of the flat type which gives radial focusing to roughly the sixth order, and which utilizes azimuthal variation of the field coefficients, has been devised.
Date: April 6, 1966
Creator: Bergkvist, Karl-Erik & Sessler, Andrew M.
System: The UNT Digital Library
Monochromatic Cosmic Ray Deuterion Source (open access)

Monochromatic Cosmic Ray Deuterion Source

The reaction pp {yields} {pi}{sup +}d resulting from the high energy cosmic rays incident on the interstellar hydrogen gas gives rise to secondary deuterons. Since the total cross section for this reaction is appreciable only at proton kinetic energies of 600 MeV, the deuterons have a very small spread in energy. It is estimated that the flux of deuterons from this mechanism should be easily discernible from deuterons produced by other reactions and copious enough to be detected at the earth. The narrow deuteron energy distribution could provide an energy calibration for the study of the existence of a postinjection acceleration.
Date: August 6, 1968
Creator: Anderson, Jared A.
System: The UNT Digital Library
Direct Conversion of Neutron Energy and Other Advantages of a Large Yield Per Pulse, Inertial-Confinement Fusion Reactor (open access)

Direct Conversion of Neutron Energy and Other Advantages of a Large Yield Per Pulse, Inertial-Confinement Fusion Reactor

Aspects of an inertial-confinement, fusion reactor that uses an energy release {approx gt}10{sup 11} joules are discussed. The large energy release makes possible direct conversion of the fusion neutrons' energy after nuclear heating of an evaporated blanket to the plasma state. Surface damage by charged particles is avoided and structural damage by neutrons is alleviated. Complex fuel assemblies and other expandable parts may be used as a result of the high monetary value of the energy release.
Date: May 6, 1974
Creator: Burke, R. J. & Cutting, J. C.
System: The UNT Digital Library
Active readout KAP x-ray spectrometer. [Laser-produced plasma diagnostics] (open access)

Active readout KAP x-ray spectrometer. [Laser-produced plasma diagnostics]

It was found that a new type of solid-state detector known as the self-scanning photodiode array can be used to obtain the active readout of data in wavelength-dispersive x-ray spectrometers. The use of this device to recover x-ray spectral data for glass microspheres heated by Lawrence Livermore Laboratory's CYCLOPS laser is reported. The self-scanning photodiode array is a product of the MOS electronics fabrication technology. It consists of an array of semi-discrete diffused junction photodiodes deployed along a line on a silicon chip. The signals generated in the array of diodes are serially-scanned and multiplexed by a scanning circuit built on the chip. The sensitivity and other aspects of the response of the photodiode arrays to low-energy x-rays has been previously reported. The photodiode array was used in conjunction with a flat KAP single-crystal in a series of spectrometry experiments. Of particular interest has been the analysis of the hydrogen-like and helium-like 1s-2p radiations of silicon in the neighborhood of 2 keV.
Date: October 6, 1975
Creator: Koppel, L. N.; Richards, L. M. & Campbell, D. E.
System: The UNT Digital Library
Spectral measurements of x-rays and electrons emitted from 1. 06. mu. m laser produced plasmas (open access)

Spectral measurements of x-rays and electrons emitted from 1. 06. mu. m laser produced plasmas

Absolute spectral measurements were made of electrons escaping from plasmas produced by focusing 5-10 J, 50-100 picosecond, 1.06 ..mu..m laser pulses on 10 ..mu..m thick Parylene disk targets. Nine spectral bands with 3 to 7.5 keV resolution were obtained from 30 to 190 keV using a 90/sup 0/ focusing permanent magnet spectrometer and appropriately positioned silicon electron detectors.
Date: October 6, 1975
Creator: Tirsell, K. G.; Kornblum, H. N.; Catron, H. C. & Slivinsky, V. W.
System: The UNT Digital Library
X-ray line spectra from DT filled SiO/sub 2/ microshells (open access)

X-ray line spectra from DT filled SiO/sub 2/ microshells

This paper is a discussion of curved crystal x-ray spectrometry of laser induced plasmas for h..nu.. < 4 keV. The plasmas were produced by a short pulse (<200 ps) of 1.06 ..mu.. (neodymium glass) radiation on glass shells on the order of a hundred ..mu..m in diameter and a micron thick. Total absorbed laser energy is of the order of 10 joules and x-radiation .01-.1 joule/sr. The shells were filled with DT gas under compression.
Date: October 6, 1975
Creator: Richards, L. & Eckels, D.
System: The UNT Digital Library
High-intensity, subkilovolt x-ray calibration facility. [Cockroft--Walton accelerator facility] (open access)

High-intensity, subkilovolt x-ray calibration facility. [Cockroft--Walton accelerator facility]

A high-intensity subkilovolt x-ray calibration source utilizing proton-induced inner-shell atomic fluorescence of low-Z elements is described. The high photon yields and low bremsstrahlung background associated with this phenomenon are ideally suited to provide intense, nearly monoenergetic x-ray beams. The proton accelerator is a 3 mA, 300 kV Cockroft-Walton using a conventional rf hydrogen ion source. Seven remotely-selectable targets capable of heat dissipation of 5 kW/cm/sup 2/ are used to provide characteristic x-rays with energies between 100 and 1000 eV. Source strengths are of the order of 10/sup 13/ to 10/sup 14/ photons/sec. Methods of reducing spectral contamination due to hydrocarbon build-up on the target are discussed. Typical x-ray spectra (Cu-L, C-K and B-K) are shown.
Date: May 6, 1976
Creator: Kuckuck, R. W.; Gaines, J. L. & Ernst, R. D.
System: The UNT Digital Library
Method for determining branching ratios and cross sections of optical transitions in an atomic beam (open access)

Method for determining branching ratios and cross sections of optical transitions in an atomic beam

A general method for determining the branching ratio for an optical transition in neutral atom atomic beams is described. By utilizing the value of the branching ratio obtained, and the lifetime of the upper level, high precision absolute cross sections can be determined.
Date: July 6, 1976
Creator: Carlson, L. R.; Worden, E. F. & Johnson, S. A.
System: The UNT Digital Library
2XIIB plasma confinement experiments (open access)

2XIIB plasma confinement experiments

This paper reports results of 2XIIB neutral-beam injection experiments with plasma-stream stabilization. The plasma stream is provided either by a pulsed plasma generator located on the field lines outside the plasma region or by ionization of neutral gas introduced at the mirror throat. In the latter case, the gas is ionized by the normal particle flux through the magnetic mirror. A method of plasma startup and sustenance in a steady-state magnetic field is reported in which the plasma stream from the pulsed plasma generator serves as the initial target for the neutral beams. After an energetic plasma of sufficient density is established, the plasma generator stream is replaced by the gas-fed stream. Lifetimes of the stabilized plasma increase with plasma temperature in agreement with the plasma stabilization of the drift-cyclotron loss-cone mode. The following plasma parameters are attained using the pulsed plasma generator for stabilization: n approximately 5 x 10/sup 13/ cm/sup -3/, anti W/sub i/ approximately 13 keV, T/sub e/ = 140 eV, and ntau/sub p/ approximately 7 x 10/sup 10/ cm/sup -3/.s. With the gas feed, the mean deuterium ion energy is 9 keV and the peak density n approximately 10/sup 14/ cm/sup -3/. In the latter case, …
Date: August 6, 1976
Creator: Coensgen, F. H.; Clauser, J. F. & Correll, D. L.
System: The UNT Digital Library
Simultaneous reactions at disk and porous electrodes (open access)

Simultaneous reactions at disk and porous electrodes

Advances in electrochemical engineering are reviewed and the methodology of analysis of electrochemical systems outlined. Examples illustrative of current research concern simultaneous reactions for flow-through porous electrodes and the more fundamental system of a rotating-disk electrode. Here the undesirable side reaction is the formation of dissolved hydrogen, and the main reaction is the deposition of copper from sulfuric acid solutions. Distributions of reaction rate, concentration, and potential describe the detailed system behavior. The side reaction is responsible for the poorly defined limiting-current plateau on the disk electrode and provides a limit for the maximum flow rate at which good recovery can be achieved with the porous electrode. 16 figures.
Date: September 6, 1976
Creator: Newman, J.
System: The UNT Digital Library
Review of radiative transitions and decays of psi and psi' (open access)

Review of radiative transitions and decays of psi and psi'

Theoretical ideas about the new particle spectrum and dynamics are compared with the experimental data for the radiative transitions and decays of psi' and psi.
Date: October 6, 1976
Creator: Chanowitz, M. S.
System: The UNT Digital Library
National Waste Terminal Storage Program information meeting, December 7-8, 1976. [Slides only, no text] (open access)

National Waste Terminal Storage Program information meeting, December 7-8, 1976. [Slides only, no text]

Volume II of the report comprises copies of the slides from the talks presented at the second session of the National Waste Terminal Storage Program information meeting. This session was devoted to geologic studies. (LK)
Date: December 6, 1976
Creator: unknown
System: The UNT Digital Library
High-temperature borate liquids: physical properties of glass-forming compositions (open access)

High-temperature borate liquids: physical properties of glass-forming compositions

Several experimental routes can be used to develop a better understanding of the polymeric constitution (polyanionic and/or polyhedral distribution) of borate, germanate, and silicate glasses. Spectral, chemical, physical-chemical, and mechanical property information can be determined directly for the glass compositions of interest. Generally, only physical-chemical information is readily accessible for the corresponding high temperature liquids. It will be shown that information on each state of matter has its own particular merits. Most of the evidence thus far published suggests an excellent agreement between polyhedral distributions in an oxide glass and its corresponding high temperature liquid state. There is no well known oxide glass forming system for which such a state of affairs does not exist. In spite of this, occasional efforts are put forth which ignore some of what is known for oxide liquids, glasses, and crystals. Such attempts therefore invariably imply, if only indirectly, that significant changes occur in the polyhedral distributions close to the glass transition temperature region. Specific examples to be discussed will include efforts that avoid well known coordination change equilibria such as BO/sub 3/ reversible BO/sub 4/ and GeO/sub 4/ reversible GeO/sub 6/.
Date: May 6, 1977
Creator: Riebling, E.F.
System: The UNT Digital Library
Determination of sound velocity in liquid metals at temperatures above 4000 K (open access)

Determination of sound velocity in liquid metals at temperatures above 4000 K

Present techniques for measuring sound velocity in liquid metals have been limited by transducers that cannot survive in extreme temperatures for the long periods these techniques require. We are developing an alternative, noncontacting technique that takes very little time (approximately 1 ..mu..s) and can be used at very high temperatures (above 6000 K). We hope to use this method with our isobaric-expansion apparatus, in which we measure the thermal expansion, enthalpy, and temperature of wire samples electrically heated under high-pressure argon gas. Because we can already determine the specific heat C/sub p/ and the bulk thermal-expansion coefficient ..cap alpha.. for liquid metals, sound-velocity measurement would allow us to determine the Gruneisen parameter ..gamma../sub G/, specific heat C/sub v/, isothermal compressibility K/sub T/, entropy derivative (delta S/delta v)/sub T/, and internal-energy derivative (delta u/delta v)/sub T/. This paper describes this technique and the progress we have made with it to date.
Date: June 6, 1977
Creator: Gathers, G. R.; Shaner, J. W.; Calder, C. A. & Wilcox, W. W.
System: The UNT Digital Library
Mechanical structure of the Mirror Hybrid Reactor Power Plant (open access)

Mechanical structure of the Mirror Hybrid Reactor Power Plant

The mechanical structure of the LLL/GA Mirror Hybrid Reactor vessel is briefly discussed. Functional requirements and over-all design considerations leading to selection of a post-tensioned concrete reactor vessel and a modular blanket approach are indicated. Module design life of four years, module replacement, capability and remote fueling are provided by the chosen structural design. (RME)
Date: June 6, 1977
Creator: Culver, D.W. & Neef, W.S.
System: The UNT Digital Library
Shock compression of pyrolytic, ceylon natural, and a hot-pressed synthetic graphite to 120 GPa (open access)

Shock compression of pyrolytic, ceylon natural, and a hot-pressed synthetic graphite to 120 GPa

Recent improvements have made the two-stage, light-gas gun at Lawrence Livermore Laboratory into a dependable source of very energetic planar shocks. Also, the inclined-prism technique has proved useful in observing anomalous behavior of materials, especially at low pressure. The availability of these improved techniques presented an opportunity to re-examine the low pressure, shock-compression characteristics for graphite and, in a search for an additional transformation, to extend some of the data to higher pressures.
Date: June 6, 1977
Creator: Gust, W. H. & Young, D. A.
System: The UNT Digital Library
Design of the calorimeter and beam dump for the TFTR prototype neutral beam injector (open access)

Design of the calorimeter and beam dump for the TFTR prototype neutral beam injector

A calorimeter has been designed for use with the TFTR prototype neutral beam injection system. It consists of three vees each having two 18.8-mm-thick (0.75 in.) copper plates at a 6-deg angle, relative to the beam centerline. The maximum power density on a plate with this arrangement will be 2.0 kW/cm/sup 2/, resulting in a front surface temperature rise of about 420/sup 0/C. A support and retraction system moves the calorimeter in and out of the beam centerline. Various factors used in the selection of the absorber plate material will be discussed and also some experimental test results will be presented.
Date: October 6, 1977
Creator: Stone, R.R. & Haughian, J.M.
System: The UNT Digital Library
Fueling with neutral beams (open access)

Fueling with neutral beams

Neutral beams, which effectively heat and fuel mirror reactors, provide high-energy particles that readily cross magnetic fields to penetrate, heat, and fuel confined plasmas. The potential reliability, efficiency, and cost of large neutral-beam injectors make them desirable components of an operating mirror reactor. Because neutral beams are a poor source of low-energy particles, some other means of fueling large Tokamaks is needed.
Date: October 6, 1977
Creator: Fink, J.H.
System: The UNT Digital Library
LASNEX code for inertial confinement fusion (open access)

LASNEX code for inertial confinement fusion

A brief description is presented of the physical processes, models and numerical methods employed in the LASNEX code for calculating inertial confinement fusion.
Date: October 6, 1977
Creator: Zimmerman, G.; Kershaw, D.; Bailey, D. & Harte, J.
System: The UNT Digital Library
Mechanical design criteria for continuously operating neutral beams (open access)

Mechanical design criteria for continuously operating neutral beams

Mechanical design criteria for high-energy neutral beam injectors capable of prolonged operation are examined. The generalized structural, heat transfer, and hydraulics equations are presented for convectively cooled grids. The effectiveness of helium, liquid sodium, and subcooled water for cooling a 2-mm-diameter, 8-m-long grid tube is shown. Cooling effectiveness is determined as a function of the number of tubes in series vs heat flux, where the number of tubes in series ranges from 1 to 100 and the heat flux ranges from 100 to 10,000 W/cm/sup 2/. The stress analysis of the grid tube walls is presented, enabling data to be added to the heat transfer graphs and giving an upper flux limit for some grid materials. Sputtering is found to be a possible limiting factor for the grid lifetimes. In injectors designed for continuous use, long-term operation without excessive maintenance is required and sputtering must be minimized. To accomplish this, several procedures are proposed.
Date: October 6, 1977
Creator: Vosen, S. R.; Bender, D. J.; Fink, J. H. & Lee, J. D.
System: The UNT Digital Library
Damage history of Argus, a 4TW Nd-glass system (open access)

Damage history of Argus, a 4TW Nd-glass system

Argus is a twin beam, 20 cm output aperture, Nd:glass laser system that has delivered 4TW to a laser fusion target. This performance is based on the concepts that multiple spatial filtering can prevent beam fill factors. Damage to optics due to self focusing and filamentation does not occur on Argus. The only form of damage is induced by broadband radiation from xenon flashlamps interacting with contaminants on or in the Nd:glass. The severity of damage is measured by the fraction of the beam obscured by the damage sites. This averages 0.1% per surface or 0.75% per arm. The amount of damage does not appear to be strongly related to the number of amplifier firings and generally occurs during the first few firings.
Date: December 6, 1977
Creator: Stowers, I.F. & Patton, H.G.
System: The UNT Digital Library
Positive ion systems: state of the art and ultimate potential (open access)

Positive ion systems: state of the art and ultimate potential

The PLT or ISX-B ion source has been operated at 40-keV, 60-A, and 0.3-sec pulses with H(D) neutral injected power of 750 kW (approximately 1000 kW) on the PLT device. This report gives a brief description of this system and some future plans. (MOW)
Date: December 6, 1977
Creator: Haselton, H.H.
System: The UNT Digital Library
Waste management strategy for nuclear fusion power systems from a regulatory perspective (open access)

Waste management strategy for nuclear fusion power systems from a regulatory perspective

A waste management strategy for future nuclear fusion power systems is developed using existing regulatory methodology. The first step is the development of a reference fuel cycle. Next, the waste streams from such a facility are identified. Then a waste management system is defined to safely handle and dispose of these wastes. The future regulator must identify the decisions necessary to establish waste management performance criteria. The data base and methodologies necessary to make these decisions must then be developed. Safe management of nuclear fusion wastes is not only a technological challenge, but encompasses significant social, political, and ethical questions as well.
Date: December 6, 1977
Creator: Heckman, R.A.
System: The UNT Digital Library
Noncontact material testing using laser energy deposition and interferometry (open access)

Noncontact material testing using laser energy deposition and interferometry

A technique is described for the noncontact testing of materials using laser deposition to generate a stress pulse and interferometry to record the transient surface displacement. The dilatational wave speed can be measured and, in the particular case of rod or plate specimens, sufficient information can be obtained to evaluate the two elastic constants of an isotropic material. Several applications illustrating the advantages of the approach are summarized.
Date: February 6, 1978
Creator: Calder, C.A. & Wilcox, W.W.
System: The UNT Digital Library