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Mirror hybrid reactor studies (open access)

Mirror hybrid reactor studies

The hybrid reactor studies are reviewed. The optimization of the point design and work on a reference design are described. The status of the nuclear analysis of fast spectrum blankets, systems studies for fissile fuel producing hybrid reactor, and the mechanical design of the machine are reviewed. (MHR)
Date: January 19, 1978
Creator: Bender, D.J.
System: The UNT Digital Library
Equilibrium water vapor pressure over adhesives and epoxies (open access)

Equilibrium water vapor pressure over adhesives and epoxies

None
Date: May 19, 1975
Creator: Colmenares, C. & McDavid, L.
System: The UNT Digital Library
Notes on Luminosity Variation at ISABELLE (open access)

Notes on Luminosity Variation at ISABELLE

In the present ISABELLE design, the luminosity at each insertion will be the same, unless special efforts are taken to get a low-..beta.. insertion or reduced crossing angle. These can only change the luminosity by factors of 2 to 4 from insertion to insertion. An estimation of the range of desired luminosities is given.
Date: October 19, 1977
Creator: Herrera, J. C.; Marx, M.; Roe, B. & Rosenberg, E. I.
System: The UNT Digital Library
Determination of chloride contamination on detonator components by SAM and ESCA (open access)

Determination of chloride contamination on detonator components by SAM and ESCA

None
Date: May 19, 1975
Creator: Colmenares, C.
System: The UNT Digital Library
Superconductor development program at Lawrence Livermore Laboratory (open access)

Superconductor development program at Lawrence Livermore Laboratory

Winding of a Nb--Ti test coil at the Lawrence Livermore Laboratory is nearly complete. The conductor in this coil operates in a maximum field of 7.5 T and provides the 2-T field required by the Mirror Fusion Test Facility. Nb/sub 3/Sn multifilamentary conductors, made using the ''bronze'' technique, appear capable of providing the higher fields needed by commercial reactors.
Date: January 19, 1978
Creator: Cornish, D.N.
System: The UNT Digital Library
Methods and calculations for regional, continental, and global dose assessments from a hypothetical fuel reprocessing facility (open access)

Methods and calculations for regional, continental, and global dose assessments from a hypothetical fuel reprocessing facility

The Savannah River Laboratory (SRL) is coordinating an interlaboratory effort to provide, test, and use state-of-the-art methods for calculating the environmental impact to an offsite population from the normal releases of radionuclides during the routine operation of a fuel-reprocessing plant. Results of this effort are the estimated doses to regional, continental, and global populations. Estimates are based upon operation of a hypothetical reprocessing plant at a site in the southeastern United States. The hypothetical plant will reprocess fuel used at a burn rate of 30 megawatts/metric ton and a burnup of 33,000 megawatt days/metric ton. All fuel will have been cooled for at least 365 days. The plant will have a 10 metric ton/day capacity and an assumed 3000 metric ton/year (82 percent online plant operation) output. Lifetime of the plant is assumed to be 40 years.
Date: March 19, 1978
Creator: Schubert, J. F.; Kern, C. D.; Cooper, R. E. & Watts, J. R.
System: The UNT Digital Library
Attack of stainless steel type 2169 by decomposition products of TATB studied by Auger spectroscopy and ESCA (open access)

Attack of stainless steel type 2169 by decomposition products of TATB studied by Auger spectroscopy and ESCA

None
Date: May 19, 1975
Creator: Colmenares, C.; Meisenheimer, R.; Smith, R.L. & Fischer, J.W.
System: The UNT Digital Library
Tokamak Fusion Test Reactor neutral beam injection system vacuum chamber (open access)

Tokamak Fusion Test Reactor neutral beam injection system vacuum chamber

Most of the components of the Neutral Beam Lines of the Tokamak Fusion Test Reactor (TFTR) will be enclosed in a 50 cubic meter box-shaped vacuum chamber. The chamber will have a number of unorthodox features to accomodate both neutral beam and TFTR requirements. The design constraints, and the resulting chamber design, are presented.
Date: October 19, 1977
Creator: Pedrotti, L.R.
System: The UNT Digital Library
Nature and effects of ion-cyclotron fluctuations in TMX (open access)

Nature and effects of ion-cyclotron fluctuations in TMX

In the tandem mirror experiment (TMX), coherent oscillations have been identified as resulting from the Alfven ion-cyclotron instability. Although the drive for this instability is localized in the end cell, the waves generated propagate out of the unstable region and interact with the central-cell ions. This interaction leads to an experimentally observed scaling of the stored end-cell energy with axial ion end-loss current.
Date: February 19, 1982
Creator: Casper, T. A.; Poulsen, P. & Smith, G. R.
System: The UNT Digital Library
Ultra-high Photoresponsivity in Suspended Metal-Semiconductor-Metal Mesoscopic Multilayer MoSâ‚‚ Broadband Detector from UV-to-IR with Low Schottky Barrier Contacts (open access)

Ultra-high Photoresponsivity in Suspended Metal-Semiconductor-Metal Mesoscopic Multilayer MoSâ‚‚ Broadband Detector from UV-to-IR with Low Schottky Barrier Contacts

This article describes the performance of a multifaceted investigation comprising of atomic force microscopy (AFM0, photoluminescence (PL) and Raman spectroscopy to analyze the structural and chemical characteristics to help shed insights on the origins of the superior optoelectronic device performance.
Date: February 23, 2017
Creator: Saenz, Gustavo A.; Karapetrov, Goran; Curtis, James & Kaul, Anupama
System: The UNT Digital Library
Ion-beam inertial fusion: the requirements posed by target and deposition physics (open access)

Ion-beam inertial fusion: the requirements posed by target and deposition physics

The demonstration of ICF scientific feasibility requires success in target design, driver development and target fabrication. Since these are interrelated, we present here some results of ion beam target studies and relate them to parameters of interest to ion accelerators. Ion deposition physics have long been a well known subject apart from high beam currents. Recent NRL experiments at up to 250 kA/cm/sup 2/ ions confirm the classical deposition physics now at current densities which are comparable to most ion targets. On the other hand, GSI data at low current density but 1 to 10 MeV/nucleon are continually being accumulated. They have yet to find anomalous results. Relying on target concepts outlined briefly, we report on the energy gain of ion-driven fusion targets as a function of input energy, ion ranges and focal spot radius. We also comment on some consequences of target gain versus driver and reactor requirements.
Date: October 19, 1981
Creator: Mark, J.W.K.
System: The UNT Digital Library
Performance of Argus as a laser fusion facility (open access)

Performance of Argus as a laser fusion facility

During the fifteen months that the Argus laser facility has been operating we have had two primary goals. These are: (1) to provide focusable, well characterized, high power beams for laser fusion experiments and (2) to further understand the propagation of high power and energy pulses. The propagation experiments have already led to increases in the laser output power and system reliability. Pulses appropriate for advanced targets are shaped to optimize the compression and heating of the target. In general they stress the laser in both limits of energy and power. In this work several results significant to the laser fusion program were realized. The neutron output of fusion targets increased by almost two orders of magnitude to more than 10/sup 9/ neutron/shot. An improved beam propagation technique (image relaying) was developed and partially implemented. It increased the focusable output power for short pulses (30-100 ps) to more than 4.0 TW. More than one kilojoule/beam was extracted from the laser in a high quality beam in a one nanosecond Gaussian pulse. A complex two step optical pulse was generated and successfully amplified to peak powers of more than 3.0 TW. The most recent of the system upgrades are complete image …
Date: September 19, 1977
Creator: Speck, D. R.; Simmons, W. W.; Hunt, J. T.; Boyle, M. J.; Rainer, F.; Storm, E. K. et al.
System: The UNT Digital Library
Use of x-ray imaging on laser fusion experiments (open access)

Use of x-ray imaging on laser fusion experiments

A variety of x-ray imaging techniques have been used to study the absorption, transport and implosion characteristics of exploding pusher microsphere targets irradiated with 1.06 ..mu..m light. Multichannel grazing incidence reflection microscopy, zone plate coded imaging and spatially resolved x-ray spectroscopy have observed the thermal and suprathermal x-ray emission associated with these phenomena. A second generation of x-ray imaging devices, designed for forthcoming high density implosion experiments, including axisymmetric x-ray microscopes and 1- and 2-D crystal line imaging devices, will also be briefly discussed.
Date: September 19, 1977
Creator: Boyle, M. J.; Attwood, D. T.; Ceglio, N. M.; Koppel, L. N.; Slivinsky, V. W.; Larsen, J. T. et al.
System: The UNT Digital Library
Performance of a Nova beamline with high damage threshold glass (open access)

Performance of a Nova beamline with high damage threshold glass

We report on measurements made on a Nova beamline whose output amplifier stages contain new high damage threshold, platinum particle-free laser glass. We project future operating limits for the Nova ten beam amplifier system. 4 refs.
Date: November 19, 1987
Creator: Bibeau, C.; Ehrlich, R. B.; Lawson, J. K.; Laumann, C. W.; Pennington, D. M.; Weiland, T. L. et al.
System: The UNT Digital Library
Delay line proportional chambers for the Fermilab external muon identifier (open access)

Delay line proportional chambers for the Fermilab external muon identifier

Thirty-nine one meter square proportional chambers with delay line readout were constructed for the external muon identifier of the Fermilab 15 foot bubble chamber. They provide X,Y,U(45/sup 0/) and T (avalanche time) information using a single wire plane, etched strip cathodes and nine amplifiers. They have a time resolution of +-27ns, single particle spatial resolution of +-2 to +-3mm and double particle resolution of approximately 2/sup 1///sub 2/ to 4cm. The energy accessible to each wire is limited so none of the wires in the first 25 chambers has broken since their installation in 1973 to 1974.
Date: October 19, 1977
Creator: Parker, S.; Orthel, J. & Marriner, J.
System: The UNT Digital Library
Design and implementation of a fiber-optic gamma-measurement system (open access)

Design and implementation of a fiber-optic gamma-measurement system

The design and implementation of the downhole portion of a measuring system for gamma rays is presented. Included are three alternative designs for radiation-resistant collimating and condensing lenses, sample cells, turning mirrors, and fiber-optic termination techniques. Also discussed are mechanical mounts and positioners, shielding, alignment, test methods, and field installation. Some general design suggestions for optical systems in adverse environments are also presented.
Date: May 19, 1980
Creator: Reedy, R.P.; Crawford, D.W. & Roeske, F. Jr.
System: The UNT Digital Library
Explosive vaporization of small droplets (open access)

Explosive vaporization of small droplets

A model has been created of the explosive vaporization of small droplets by the absorption of energy from a high energy laser beam. The model consists of a polarizable drop of fluid interacting with laser radiation. A criterion for the explosion of the droplet has been introduced. Selfsimilarity is invoked to reduce the spherically symmetric problem involving hydrodynamics and Maxwell's equations to simple quadrature. Experimental evidence in favor of the model is cited.
Date: August 19, 1986
Creator: Chitanvis, S.M.
System: The UNT Digital Library
Neutron capture studies: 1, Multiple capture reactions and implications for calculated beta-delayed fission rates: 2, The nuclear level structure of 238Np (open access)

Neutron capture studies: 1, Multiple capture reactions and implications for calculated beta-delayed fission rates: 2, The nuclear level structure of 238Np

Astrophysical r-process calculations of transbismuth elements are of interest because certain actinide pairs can be treated as chronometers in determining the duration of nucleosynthesis. For one such calculation where a particularly long galactic age was derived, 21 + 2 - 4 Gyr, we present evidence that the effect of beta-delayed fission appears to be seriously overestimated in uranium decay chains with A = 252 to 257. With this conclusion, it follows that this estimate of the galactic age must be considered more uncertain than if the calculated rates of beta-delayed fission were found to be acceptable. The nuclear level structure of 238Np has been investigated using the 237Np(n,..gamma..)238Np reaction and the alpha decay of 242mAm as experimental probes. Having established a level scheme for 238Np that includes 47 excited levels and 93 secondary transitions, we find a high degree of correspondence between the experimental band structure and that of a semi-empirical model developed to predict excitations in odd-odd deformed nuclei. 35 refs., 4 figs., 3 tabs.
Date: February 19, 1988
Creator: Hoff, R.W.
System: The UNT Digital Library
Selective generation and extraction of low emittance electrons from plasmas: A new concept for E-beam cathodes (open access)

Selective generation and extraction of low emittance electrons from plasmas: A new concept for E-beam cathodes

It is shown that hollow cathode discharges can operate in a mode characterized by a two-component electron energy distribution: bulk electrons with a thermal distribution with a temperature of a few electron volts, and a component of fast electrons with an energy of about 30 eV and a thermal spread of about 0.1 eV. Measurements of both parallel and perpendicular energy spreads confirm the existence of fast, low energy spread electrons. Selective extraction of these electrons can form the basis of a high current, high brightness electron gun which could be well suited for EBIS applications. 8 refs., 4 figs., 1 tab.
Date: September 19, 1991
Creator: Hershcovitch, A.
System: The UNT Digital Library
X-ray lines as a density diagnostic in DT plasmas near 100x solid density (open access)

X-ray lines as a density diagnostic in DT plasmas near 100x solid density

The use of electron impact broadened resonance lines to diagnose near-term high density diagnostics is discussed. In particular, the question of how to choose seed and pusher materials to have discernible broadening effects while maintaining line visibility is discussed.
Date: October 19, 1977
Creator: Bailey, D.S.
System: The UNT Digital Library
Beryllium Science: US-UK agreement on the use of Atomic Energy for mutual defense (open access)

Beryllium Science: US-UK agreement on the use of Atomic Energy for mutual defense

Twenty-seven papers are presented on beryllium supply, production, fabrication, safe handling, analysis, powder technology, and coatings. Separate abstracts have been prepared for the individual papers. (DLC)
Date: February 19, 1988
Creator: Hanafee, J.E. (ed.)
System: The UNT Digital Library
Inertial fusion power for space applications (open access)

Inertial fusion power for space applications

More than thirty-seven design concepts have been proposed for terrestrial ICF power plants. The design space is large because of the many allowable driver and reaction chamber combinations. These design studies have illustrated advantages of ICF power plants over other sources in lower impact on the environment, high safety, and almost no dependence on consumables like fuel. The fact that, once built, a 1000 MW/sub e/ ICF power plant would require only 240 kg of deuterium and from 770 to 9260 kg of lithium to run for five years (at 70% capacity factor) makes it potentially attractive for space power also. However, the designs proposed to date have emphasized features that would make the plant attractive for terrestrial applications, where economics, efficiency, and environmental considerations dominate. The resulting plants are large and contain many very heavy components that would not be at attractive for space applications. In this paper, we evaluate alternative ICF driver and reactor technologies using space application criteria and also discuss how some of those technologies can be altered to produce smaller, lighter fusion power sources for space.
Date: May 19, 1986
Creator: Meier, W. R.; Hogan, W. J.; Hoffman, N. J.; Murray, K. A. & Olson, R. E.
System: The UNT Digital Library
Neutral beam injection system for the Tokamak Fusion Test Reactor (open access)

Neutral beam injection system for the Tokamak Fusion Test Reactor

The Tokamak Fusion Test Reactor will be installed at the Princeton Plasma Physics Laboratory facility. This is a major step to reach the goal of fusion power using toroidal magnetic fields for plasma confinement. A major part of this test reactor will be four neutral beam injection systems. These systems will inject 20 MW of 120 kV neutral deuterium atoms into the plasma for 0.5 seconds. In order to achieve the required power input to the plasma, several systems are required within the neutral beam line. These are the source, neutralizer, ion deflection magnet, calorimeter and retraction system, ion dump, cryopumps and vacuum enclosure. All of these systems have constraints imposed which increase the complexity of their designs. Since all systems must operate in a tritium environment, remote handling capabilities must be incorporated into the design. An overview is presented of the Lawrence Livermore Laboratory/Lawrence Berkeley Laboratory Neutral Beam Injection System design. Specifications for the machine and a general description of the total system are presented.
Date: October 19, 1977
Creator: Pittenger, L.C.; Stone, R.R.; Valby, L.E. & Pedrotti, L.R.
System: The UNT Digital Library
Correlation between predicted and observed levels of airborne tritium at Lawrence Livermore Laboratory site boundary (open access)

Correlation between predicted and observed levels of airborne tritium at Lawrence Livermore Laboratory site boundary

At the Lawrence Livermore Laboratory, a computer code based on the Gaussian plume model is used to estimate radiation doses from routine or accidental release of airborne radioactive material. Routine releases of tritium have been used as a test of the overall uncertainty associated with these estimates. The ration of concentration to release rate at distances from the two principal release points to each of six site boundary sampling locations has been calcuated using local meteorological data. The concentration of airborne tritiated water vapor is continuously measured at the six sampling stations as part of the Laboratory's environmental monitoring program. Comparison of predicted with observed annual tritiated water concentrations in 1978 showed an average ratio of 2.6 with a range of from 0.97 to 5.8.
Date: February 19, 1980
Creator: Lindeken, C. L.; Silver, W. J.; Toy, A. J. & White, J. H.
System: The UNT Digital Library