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Applications of induction linac technology to heavy ion fusion (open access)

Applications of induction linac technology to heavy ion fusion

Evaluation of the application of heavy ion accelerators to ignite d-t pellets in a thermonuclear reactor is discussed. Accelerator design requirements considered include transport-limited current, beam injection conditions, and pulse bunching and focusing characteristics. The desirability of resonant and non-resonant accelerating structures is comparatively examined. The required power system switch tubes are discussed. It is concluded that heavy ion accelerators could offer a promising solution to the pellet-igniter problem. The advantages pointed out for this approach include electric efficiency greater than 10 percent, the possibility of high repetition rates (1 to 10 Hz), and a mature technological base. (RME)
Date: July 1, 1977
Creator: Faltens, A. & Keefe, D.
System: The UNT Digital Library
Proceedings of the 1977 Isabelle Summer Workshop. [Seventy-four papers] (open access)

Proceedings of the 1977 Isabelle Summer Workshop. [Seventy-four papers]

A report is given of the activities of the 1977 ISABELLE Summer Workshop, held from July 18 to 29, 1977 at the Brookhaven National Laboratory. An abstract was prepared for each of the seventy-four separate presentations for inclusion in DOE Energy Research Abstracts (ERA). (PMA)
Date: July 18, 1977
Creator: unknown
System: The UNT Digital Library
Facility for the testing of the TFTR prototype neutral beam injector (open access)

Facility for the testing of the TFTR prototype neutral beam injector

The design of the prototype neutral beam injection system for TFTR is nearing completion at the Lawrence Livermore Laboratory. This paper describes some of the features of the facility at the Lawrence Berkeley Laboratory where this prototype will be assembled and tested.
Date: July 1, 1977
Creator: Haughian, J.M.
System: The UNT Digital Library
Measurement of pressure, fluidized bed level, and density in the Synthane Pilot Plant coal gasifier (open access)

Measurement of pressure, fluidized bed level, and density in the Synthane Pilot Plant coal gasifier

Fluid bed densities and levels are usually obtained from measurement of differential pressures between taps with a known vertical separation. Historically, this measurement has been difficult in high pressure coal gasification processes primarily due to plugging of the pressure taps and process instrument tubing. Likewise, the achievement of accurate and reliable pressure and differential pressure recordings is affected by similar circumstances. These typical problems were experienced at the SYNTHANE Pilot Plant at Bruceton which is operated for the U.S. Energy Research and Development Administration by the C.E. Lummus Company. Major changes were required in instrument location and selection, piping configuration, and methods of purging. Consistent and accurate data is now obtained. Recommendations for the installation and operation of such instruments are given.
Date: July 1, 1977
Creator: Bailey, D. M. & Runnels, O. D.
System: The UNT Digital Library
Brillouin scatter in laser-produced plasmas (open access)

Brillouin scatter in laser-produced plasmas

The absorption of intense laser light is found to be reduced when targets are irradiated by 1.06 ..mu..m light with long pulse widths (150-400 psec) and large focal spots (100-250 ..mu..m). Estimates of Brillouin scatter which account for the finite heat capacity of the underdense plasma predict this reduction. Spectra of the back reflected light show red shifts indicative of Brillouin scattering.
Date: July 18, 1977
Creator: Phillion, D.W.; Kruer, W.L. & Rupert, V.C.
System: The UNT Digital Library
Non-equilibrium aspects of water reactor safety (open access)

Non-equilibrium aspects of water reactor safety

A critical review of the thermal non-equilibrium phase change models applicable to the water reactor safety calculations is presented. Four specific areas are discussed: (1) rapid depressurization (flashing), (2) post-dryout heat transfer, (3) direct contact condensation, and (4) sub-cooled boiling. The models have been judged from a mechanistic viewpoint, and the areas where further work is needed have been pointed out. It is suggested that when a phase change occurs due to a difference in the bulk fluid temperatures, the non-equilibrium phase change process can be viewed as a linear, non-homogeneous thermal relaxation phenomenon. Direct measurements of the actual phase change rates and the interfacial area densities are emphasized. Finally, a recommendation for the volumetric vapor generation rates applicable to the above four specific areas is given.
Date: July 1, 1977
Creator: Jones, O.C. Jr. & Saha, P.
System: The UNT Digital Library
Conceptual design of a laser fusion power plant (open access)

Conceptual design of a laser fusion power plant

A conceptual design of a laser fusion power plant is extensively discussed. Recent advances in high gain targets are exploited in the design. A smaller blanket structure is made possible by use of a thick falling region of liquid lithium for a first wall. Major design features of the plant, reactor, and laser systems are described. A parametric analysis of performance and cost vs. design parameters is presented to show feasible design points. A more definitive follow-on conceptual design study is planned. (RME)
Date: July 14, 1977
Creator: Maniscalco, J. A.; Meier, W. R. & Monsler, M. J.
System: The UNT Digital Library
Laser driven fusion fission hybrids (open access)

Laser driven fusion fission hybrids

The role of the fusion-fission hybrid reactor (FFHR) as a fissile fuel and/or power producer is discussed. As long range options to supply the world energy needs, hybrid-fueled thermal-burner reactors are compared to liquid metal fast breeder reactors (LMFBR). A discussion of different fuel cycles (thorium, depleted uranium, and spent fuel) is presented in order to compare the energy multiplication, the production of fissile fuel, the laser efficiency and pellet gain requirements of the hybrid reactor. LLL has collaborated with Bechtel Corporation and with Westinghouse on the conceptual design of laser fusion power plants. The neutronic studies of these two designs are discussed. The operational parameters, such as energy multiplication, power density, burn-up and plutonium production as a function of time, are also presented.
Date: July 12, 1977
Creator: Hansen, L. F. & Maniscalco, J. A.
System: The UNT Digital Library
Fluorescence-pumped photolytic gas laser system for a commercial laser fusion power plant (open access)

Fluorescence-pumped photolytic gas laser system for a commercial laser fusion power plant

The first results are given for the conceptual design of a short-wavelength gas laser system suitable for use as a driver (high average power ignition source) for a commercial laser fusion power plant. A comparison of projected overall system efficiencies of photolytically excited oxygen, sulfur, selenium and iodine lasers is described, using a unique windowless laser cavity geometry which will allow scaling of single amplifier modules to 125 kJ per aperture for 1 ns pulses. On the basis of highest projected overall efficiency, a selenium laser is chosen for a conceptual power plant fusion laser system. This laser operates on the 489 nm transauroral transition of selenium, excited by photolytic dissociation of COSe by ultraviolet fluorescence radiation. Power balances and relative costs for optics, electrical power conditioning and flow conditioning of both the laser and fluorescer gas streams are discussed for a system with the following characteristics: 8 operating modules, 2 standby modules, 125 kJ per module, 1.4 pulses per second, 1.4 MW total average power. The technical issues of scaling visible and near-infrared photolytic gas laser systems to this size are discussed.
Date: July 14, 1977
Creator: Monsler, M.J.
System: The UNT Digital Library
Concerning the generation of very high pressures for EOS studies with ultra-high power laser pulses (open access)

Concerning the generation of very high pressures for EOS studies with ultra-high power laser pulses

The use of basic physical and geometric principles, coupled with current laser technology, seems likely to extend experimental hyperbaric physics investigations from the megabar region into the portions of parameter space in which the ideal (degenerate) Fermi gas approximation is valid for even the highest Z materials. Implosions and speed-multiplying rectilinear stacks of flat plates seem particularly apt techniques for the near-term, transient attainment of pressure of 10/sup 9/ atmospheres in the laboratory, and laser-energized pulsed x-ray ''cameras'' appear suitable for analyzing the basic properties of matter under such conditions.
Date: July 1, 1977
Creator: Wood, L. L.; Keeler, R. N. & Nuckolls, J. H.
System: The UNT Digital Library
Low frequency noise in freely suspended tin films at the superconducting transition. [Spectral density] (open access)

Low frequency noise in freely suspended tin films at the superconducting transition. [Spectral density]

The spectral density, S/sub v/(f), of the voltage noise across 1-D current-biased tin films has been measured at the superconducting transition. Each film was freely suspended between two thermal clamps a distance L apart in a vacuum can. A thin layer of lead was evaporated on the outer portion of the films to leave an uncoated middle region of length l. S/sub v/(f) was flat at frequencies below f/sub L/ approximately D/L/sup 2/, where D is the thermal diffusivity. At frequencies between f/sub L/ and f/sub l/ approximately (L/l)/sup 2/f/sub L/ the slope was typically -0.8, while at frequencies above f/sub l/ the slope was somewhat less steep than -1.5. The shape and magnitude of S/sub v/(f) were in good agreement with an equilibrium temperature fluctuation model in which the temperature fluctuations are spatially uncorrelated. Measurements of the autocorrelation function also strongly supported this model. These results are in contrast with those obtained for normal films and films at the superconducting transition supported by substrates, for which a model was required with spatially correlated fluctuations. It is concluded that the 1/f noise for films on substrates is mediated by an interaction between the substrate and the film.
Date: July 1, 1977
Creator: Ketchen, M.B. & Clarke, J.
System: The UNT Digital Library
Phase transformations, stability, and materials interactions (open access)

Phase transformations, stability, and materials interactions

The proceedings of the Materials Sciences Workshop on Phase Transformations, Stability, and Materials Interactions are divided into sections according to the following topics: (I) workshop scope and priorities; (II) study group reports--ERDA mission needs; (III) study group reports--technical area research priorities. (SDF)
Date: July 1, 1977
Creator: Morris, J.W. Jr.; Brewer, L.; Cost, J.R. & Shewmon, P.
System: The UNT Digital Library
Reactor concepts for laser fusion (open access)

Reactor concepts for laser fusion

Scoping studies were initiated to identify attractive reactor concepts for producing electric power with laser fusion. Several exploratory reactor concepts were developed and are being subjected to our criteria for comparing long-range sources of electrical energy: abundance, social costs, technical feasibility, and economic competitiveness. The exploratory concepts include: a liquid-lithium-cooled stainless steel manifold, a gas-cooled graphite manifold, and fluidized wall concepts, such as a liquid lithium ''waterfall'', and a ceramic-lithium pellet ''waterfall''. Two of the major reactor vessel problems affecting the technical feasibility of a laser fusion power plant are: the effects of high-energy neutrons and cyclical stresses on the blanket structure and the effects of x-rays and debris from the fusion microexplosion on the first-wall. The liquid lithium ''waterfall'' concept is presented here in more detail as an approach which effectively deals with these damaging effects.
Date: July 1, 1977
Creator: Meier, W. R. & Maniscalco, J. A.
System: The UNT Digital Library
Wind erosion research at an uranium mill tailings site (open access)

Wind erosion research at an uranium mill tailings site

A uranium mill tailings pile at Grants, New Mexico, was selected for wind erosion research since the configuration provides flat area containing fine sand and made up of larger particles. The wind erosion experiment is discussed. Experimental equipment consists of meteorological instrumentation to automatically activate air samplers as a function of wind speed increments and direction, particle cascade impactors to measure airborne respirable concentrations as a function of particle size, inertial impaction devices to measure nonrespirable fluxes of airborne particles, a virtual particle cascade impactor to measure airborne concentrations of toxic trace elements, and soil depth gauges to measure changes in surface soil elevations as a function of time. Both radioactive particles as well as toxic trace element concentrations are measured. Radioactive particles are measured with both particle cascade impactors as well as high-volume air samplers. In contrast, toxic trace element airborne concentrations are measured only with a two-stage virtual particle cascade impactor. Fluxes of nonrespirable airborne particles are measured with inertial impaction devices. At particle cascade impactor sites, a rotating cyclone preseparator collects nonrespirable particles. In addition at all sites, fluxes of nonrespirable particles are measured using an open cavity inertial impaction device. (JGB)
Date: July 1, 1977
Creator: Sehmel, G.A.
System: The UNT Digital Library
Calculation of probability table parameters to include intermediate resonance self-shielding (open access)

Calculation of probability table parameters to include intermediate resonance self-shielding

In order to demonstrate the practicality of the multi-band method (Cullen, Nucl. Sc. Eng., 55, 387 (1974)) as applied to all energy ranges, it is demonstrated that intermediate resonance effects may be included; usually only two or three, and at most four, bands are required in any cross section probability table; and a low-order rational approximation is an excellent means of defining Bonderenko sigma/sub 0/ self-shielded cross sections. 1 table.
Date: July 1, 1977
Creator: Cullen, D.E.
System: The UNT Digital Library
Adsorption Induced Losses in Interfacial Cohesion (open access)

Adsorption Induced Losses in Interfacial Cohesion

A model for interfacial cohesion is developed which describes the loss in the strength of an interface due to the segregation and adsorption of impurities on it. Distinctions are made between interface separations that occur too rapidly for any significant redistribution of adsorbing matter to take place and separations that are slow enough to allow full adsorption equilibrium. Expressions for the total work of complete decohesion are presented for both cases. The results are applied to well-known model adsorption isotherms and some experimental data for grain boundary adsorption of phosphorus in iron is analyzed with respect to the losses in intergranular cohesion.
Date: July 1, 1977
Creator: Asaro, R. J.
System: The UNT Digital Library
Theoretical interpretation of angle- and polarization-dependent laser light absorption measurements (open access)

Theoretical interpretation of angle- and polarization-dependent laser light absorption measurements

It is shown that recently published observations of angle- and polarization-dependent absorption of intense laser light are consistent with computer simulations of resonance absorption in a steepened plasma profile, with the additional assumption of a modestly rippled critical surface. About 10% absorption seems to be due to mechanisms not addressed in the simulations.
Date: July 18, 1977
Creator: Thomson, J. J.; Kruer, W. L.; Langdon, A. B.; Max, C. E. & Mead, W. C.
System: The UNT Digital Library
Transuranic and tracer simulant resuspension. [/sup 238/Pu, /sup 239/Pu, /sup 240/Pu] (open access)

Transuranic and tracer simulant resuspension. [/sup 238/Pu, /sup 239/Pu, /sup 240/Pu]

Plutonium resuspension results are summarized for experiments conducted at Rocky Flats, onsite on the Hanford reservation, and for winds blowing from offsite onto the Hanford reservation near the Prosser barricade boundary. In each case, plutonium resuspension was shown by increased airborne plutonium concentrations as a function of either wind speed or as compared to fallout levels. All measured airborne concentrations were below maximum permissible concentrations (MPC). Both plutonium and cesium concentrations on airborne soil were normalized by the quantity of airborne soil sampled. Airborne radionuclide concentrations in ..mu..Ci/g were related to published values for radionuclide concentrations on surface soils. For this ratio of radionuclide concentration per gram on airborne soil divided by that for ground surface soil, there are eight orders of magnitude uncertainty from 10/sup -4/ to 10/sup 4/. Horizontal plutonium fluxes on airborne nonrespirable soils at all three sites were bracketed within the same three to four orders of magnitude from 10/sup -7/ to 10/sup -3/ ..mu..Ci/(m/sup 2/ day) for plutonium-239 and 10/sup -8/ to 10/sup -5/ ..mu..Ci/(m/sup 2/ day) for plutonium-238. These are the entire experimental base for nonrespirable airborne plutonium transport. Airborne respirable plutonium-239 concentrations increased with wind speed for a southeast wind direction coming from …
Date: July 1, 1977
Creator: Sehmel, G. A.
System: The UNT Digital Library
Flow cytogenetics: progress toward chromosomal aberration detection. [X Radiation] (open access)

Flow cytogenetics: progress toward chromosomal aberration detection. [X Radiation]

Using clonal derivatives of the Chinese hamster M3-1 cell line, we demonstrate the potential of flow systems to karyotype homogeneous aberrations (aberrations which are identical and present in every cell) and to detect heterogeneous aberrations (aberrations which occur randomly in a population and are not identical in every cell). Flow cytometry (FCM) of ethidium bromide stained isolated chromosomes from clone 650A of the M3-1 cells distinguishes nine chromosome types from the fourteen present in the actual karyotype. X-irradiation of this parent 650A clone produced two sub-clones with an altered flow karyotype, that is, their FCM distributions were characterized by the addition of new peaks and alterations in area under existing peaks. From the relative DNA content and area for each peak, as determined by computer analysis, we predicted that each clone had undergone a reciprocal translocation involving chromosomes from two peaks. This prediction was confirmed by Giemsa-banding the metaphase cells. Heterogeneous aberrations are reflected in the flow karyotype as an increase in background, that is, an increase in area underlying the chromosome peaks. This increase is dose dependent but, as yet, the sample variability has been too large for quantitative analysis. Flow sorting of the valleys between chromosome peaks produces …
Date: July 1, 1977
Creator: Carrano, A. V.; Gray, J. W. & Van Dilla, M. A.
System: The UNT Digital Library
Field-enhanced REB deposition and Bremsstrahlung production (open access)

Field-enhanced REB deposition and Bremsstrahlung production

Recently developed models are employed to describe the interaction of a high-current REB (relativistic electron beam) with planar gold foils in the presence of macroscopic electromagnetic fields. It is shown that, under certain conditions, azimuthal magnetic fields which either penetrate into the foil and/or exist on the transmission side of the foil can significantly enhance the specific power deposited in the foil over that which would be deposited for diode fields alone. Similar field effects suggest methods for improving the external conversion efficiencies, softening the spectra and focussing the source intensities of flash x-ray facilities. Finally, preliminary results are shown from a new trajectory-field model for self-consistent REB transport.
Date: July 1977
Creator: Halbleib, J. A., Sr. & Widner, M. M.
System: The UNT Digital Library
Non-peripheral collisions of heavy ions in nuclear emulsion. [0. 2 to 2. 1 GeV/A] (open access)

Non-peripheral collisions of heavy ions in nuclear emulsion. [0. 2 to 2. 1 GeV/A]

The emulsion technique is being used to examine the angular and momentum distribution of fragments emitted from nonperipheral collisions between emulsion nuclei (AgBr) and heavy-ion projectiles /sup 4/He, /sup 16/O, and /sup 40/Ar in the range of energies 0.2 to 2.1 GeV/A. Selection criteria, scanning and measuring, measurements, and analytic procedure are addressed. Prong number distributions, range and angular distributions are shown. The following conclusions were drawn: there is no unique particle-emitting system; prong distributions dN/dtheta are broad and Maxwellian-like, with maxima that shift toward smaller angles as the fragment energy increases, and as the beam energy decreases; no statistically significant structure attributed to well-defined collective phenomena is observed; there is no evidence that the angular distribution for low-energy fragments depends on the impact parameters of the collision between heavy ions at 2.1 GeV/A; at 2.1 GeV/A the number of fragments per event emitted in the backward hemisphere is insensitive to projectile mass. 6 figures, 3 tables. (RWR)
Date: July 1, 1977
Creator: Heckman, H. H.; Crawford, H. J.; Greiner, D. E.; Lindstrom, P. J. & Wilson, L. W.
System: The UNT Digital Library
Measuring the seismic response of an HTGR core model (open access)

Measuring the seismic response of an HTGR core model

The main objective of the tests described was to provide experimental data in order to verify the analytical models used to develop HTGR core design loads. Most of the testing was performed on a one-fifth scale full array core model subjected to uniaxial horizontal excitation. The tests initially focused on evaluating the overall core frequency response, core damping, fuel element collision forces and displacements, and in particular, the lateral support response as a function of the excitation frequency and g-level. Following this series of tests, a second test program was executed on the model with emphasis placed on obtaining fuel element dowel forces and rocking angles, as well as possible element uplift. In addition, new tests were included to re-evaluate fuel element collision forces and overall core damping which were not satisfactorily obtained earlier. Several test results are included to illustrate application of the new instrumentation. Finally, a comprehensive error analysis of the test system is presented which provides estimates of the various error sources and total error in the data.
Date: July 1, 1977
Creator: Rakowski, J. E. & Olsen, B. E.
System: The UNT Digital Library
Large-scale cryopumping for controlled fusion (open access)

Large-scale cryopumping for controlled fusion

Vacuum pumping by freezing out or otherwise immobilizing the pumped gas is an old concept. In several plasma physics experiments for controlled fusion research, cryopumping has been used to provide clean, ultrahigh vacua. Present day fusion research devices, which rely almost universally upon neutral beams for heating, are high gas throughput systems, the pumping of which is best accomplished by cryopumping in the high mass-flow, moderate-to-high vacuum regime. Cryopumping systems have been developed for neutral beam injection systems on several fusion experiments (HVTS, TFTR) and are being developed for the overall pumping of a large, high-throughput mirror containment experiment (MFTF). In operation, these large cryopumps will require periodic defrosting, some schemes for which are discussed, along with other operational considerations. The development of cryopumps for fusion reactors is begun with the TFTR and MFTF systems. Likely paths for necessary further development for power-producing reactors are also discussed.
Date: July 25, 1977
Creator: Pittenger, L. C.
System: The UNT Digital Library
Metallic high pressure equation-of-state derived from experimental data (open access)

Metallic high pressure equation-of-state derived from experimental data

A program of making ''global'' fits to the large amount of experimental equation-of-state data on monatomic metals that has become available in recent years is described. The fits are made within the framework of a phenomenological scaling theory for metallic liquids which incorporates recently discovered general theoretical properties of the EOS of liquids. The theory is expected to be applicable to monatomic metals up to high temperatures (approximately 10 to 100 times the melting temperature, T/sub m/) and at all densities, so long as the metallic bonding does not change character. (GHT)
Date: July 21, 1977
Creator: Grover, Richard
System: The UNT Digital Library