Consideration is given to the stability of negative ion beams which are neutralized through ionization of a background gas. Two types of instabilities are examined. First, beam-plasma instabilities are analyzed with the dispersion relation showing that they are unimportant if the beam velocity is less than the electron thermal velocity. Second, results of a computer simulation on the flow of a cylindrical beam and the resulting background plasma show that when the background neutral gas density is less than or approximately equal to a critical density as instability occurs. This critical density is the density that would be needed to space-charge neutralize the beam if the positive ions were not retarded by the beam. An approximate dispersion relation indicates that the nature of the instability is a transverse positive-ion acoustic wave which couples to the beam.

We propose to study the utilization of high-temperature (approximately 2000-2500K) process heat from fusion reactors for large-scale chemical process applications. Of particular interest is the decomposition reaction, CO/sub 2/ ..-->.. CO + /sup 1///sub 2/O/sub 2/, which at 2500K should yield approximately 60 percent conversion to CO if O/sub 2/ is partially removed through an oxide membrane. Hydrogen can be derived from CO at lower temperatures by reacting CO with steam, and C can also be derived from CO by a disproportionation into C and CO/sub 2/ at approximately 1000K. These chemicals, CO, H/sub 2/, and C, form the basis for a multitude of non-electrical energy applications in the areas of transportation, industrial processes, and residential and commercial uses. In addition to the CO/sub 2/ decomposition process, we propose to explore a variety of ideas and evaluate them for scientific and economic merit. A follow-on research and development program will be proposed if the ideas prove promising.

A number of mechanical and electrical measurements were made on joints in typical conductors for the proposed mirror fusion test facility (MFTF) and high field test facility (HFTF). For such measurements, a commercially available cold-pressure-welding machine was used. For joints in the MFTF conductor, which has a large proportion of superconductor, joint strength approached conductor strength. For the HFTF conductor, where the Cu-to-superconductor ratio is 4.33/1, the joint is stronger than the conductor. Electrically, the joints were not superconducting.. While the resistance is higher than might be achieved by other forms of joining, we feel that the cold-weld joint has the advantages of simplicity, speed, reliability, and reproducibility. This makes the method attractive for MFTF, where resistance losses will be small compared with the total 4 K refrigeration requirements.

A particularly simple problem exhibiting stochasticity is the motion of a charged particle in a uniform magnetic field and a single wave. Detailed studies of this wave-particle interaction show the following features. An electrostatic wave propagating obliquely to the magnetic field causes stochastic motion if the wave amplitude exceeds a certain threshold. The overlap of cyclotron resonances then destroys a constant of the motion, allowing strong particle acceleration. A wave of large enough amplitude would thus suffer severe damping and lead to rapid heating of a particle distribution. The stochastic motion resembles a diffusion process even though the wave spectrum contains only a single wave. The motion of ions in a nonuniform magnetic field and a single electrostatic wave is treated in our study of a possible saturation mechanism of the dissipative trapped-ion instability in a tokamak. A theory involving the overlap of bounce resonances predicts the main features found in the numerical integration of the equations of motion. Ions in a layer near the trapped-circulating boundary move stochastically. This motion leads to nonlinear stabilization mechanisms which are described qualitatively.

The geothermal resources of California's Imperial Valley have the potential for the production of an estimated 3000 to 5000 MW/yr of electricity for 30 yr, provided that adeuqate cooling water is available for power plants. There are five possible sources of cooling water: irrigation water, waste waters from agriculture, steam condensate, ground water, and water from the Salton Sea. Technical, environmental, and regulatory constraints, however, could limit the availability of the water supplies. Of particular concern are the constraints that could be imposed if different water policies were implemented. To study how future policies could affect geothermal development, six combinations of various policies were defined to represent potential regulatory controls. A range of future water balances in the valley was also specified. The water balances plus the six policy combinations were used to determine whether deficits of cooling water would eventually constrain low, medium, or high levels of geothermal energy production. A companion analysis of changes in the elevation and salinity of the Salton Sea resulting from the use of agricultural waters for cooling was also made.

A FORTRAN code to evaluate binary reaction rates (sigmav) for a plasma to a specified accuracy is described. Distribution functions permitted are (1) two Maxwellian species at different temperatures, (2) beam-Maxwellian, (3) cold gas with Maxwellian, and (4) beam-plasma with mirror distribution of the form f(v) varies as f(v) M (cos theta). Several functional forms are permitted for f(v) and M(cos theta). Cross-section subroutines for a number of interactions involving hydrogen, helium, and electrons are included, as is a routine allowing input of numerical data. The code is written as a subroutine to allow ready incorporation into larger plasma codes.

Performance of laser fusion targets depends critically on the characteristics of the incident beam. The spatial distribution and temporal behavior of the light incident on the target varies significantly with power, with choice of beam spatial profile and with location of spatial filters. On each ARGUS shot we photograph planes in the incident beams which are equivalent to the target plane. Array cameras record the time integrated energy distributions and streak cameras record the temporal behavior. Computer reduction of the photographic data provides detailed spatial energy distributions, and instantaneous power on target vs. time. Target performance correlates with the observed beam characteristics.

In this work, along with a previous paper three possible uses of 14-MeV deuterium--tritium fusion neutrons are investigated: energy production, neutron multiplication, and fissile-fuel breeding. The results presented include neutronic studies of fissioning and nonfissioning thorium systems, tritium breeding systems, various fuel options (UO/sub 2/, UC, UC/sub 2/, etc.), and uranium as well as refractory metal first-wall neutron-multiplying regions. A brief energy balance and an estimate of potential revenues for fusion devices are given to help illustrate the potentials of these designs.

The uranium-niobium alloy system was examined in the range of 5.3-to-6.9 weight percent niobium with respect to shape memory, mechanical properties, metallography, Coefficients of linear thermal expansion, and differential thermal analysis. Shape memory increased with increasing niobium levels in the study range. There were no useful correlations found between shape memory and the other tests. Coefficients of linear thermal expansion tests of as-quenched 5.8 and 6.2 weight percent niobium specimens, but not 5.3 and 6.9 weight percent niobium specimens, had a contraction component on heating, but the phenomenon was not a contributor to shape memory.

Efforts this past quarter were directed toward the determination of dissolution parameters in various reagents of PuO/sub 2/, PuO/sub 2/-UO/sub 2/ solid solution, and AmO/sub 2/-PuO/sub 2/. The reagents used were various concentrations of HNO/sub 3/-HF-H/sub 2/SO/sub 4/, HNO/sub 3/-HF, HNO/sub 3/-(NH/sub 4/)/sub 2/Ce(NO/sub 3/)/sub 6/, and HNO/sub 3/-H/sub 2/SO/sub 4/. In one series of tests, simulated contaminated HEPA filter media were used. This material was prepared by mixing shredded filter media with actinide oxides. In another series, actual HEPA glovebox filter media contaminated with PuO/sub 2/ were used. Fusion tests were also completed using simulated PuO/sub 2/ contaminated filter media. Both Na/sub 2/CO/sub 3/ and Na/sub 2/CO/sub 3/-KNO/sub 3/ were investigated as possible fusion agents.

Observations on the use of the SEMPEX computer code are given. The issues of proper sampling rate and total sampling interval are addressed. The effect that noise in the data has on the results and the ability of autocorrelation, truncation filtering, and the sliding-window technique to reduce these effects are also discussed. 35 figures, 24 tables.

We propose an extension of the present p-p small angle scattering experiment to a measurement of p-d scattering using a deuterium gas jet. In 400 hours of beam time we will measure as a function of energy; (a) the slope of the small angle p-d scattering; (b) the real part of the forward p-d scattering; (c) the total p-d cross section; and (d) the coherent diffraction dissociation of protons on deuterons. No new apparatus is required or need be installed for the performance of this experiment.

Experimental data on the mechanical properties of reactor graphites (excluding irradiation creep and fatigue) under High-Temperature Gas-Cooled Reactor (HTGR) conditions are reviewed. Based on an assessment of the literature, recommendations are made for design-basis values for the elastic properties and strength of irradiated graphite, and failure criteria are suggested for particular loading conditions. 78 references. (auth)

High purity copper foils were irradiated with 14.8-MeV neutrons from the rotating target neutron source facility at LLL. The average energy of the neutrons was 14.75 +- 0.1 MeV, and the average fluence was 7.0 x 10$sup 16$ n/ cm$sup 2$. After irradiation each foil was heated to the melting point and the released helium was measured by a mass spectrometer of special design. Isochronal heating was carried out on several samples to establish the type and temperature of maximum release. Calculated cross sections from the literature for the (eta,$alpha$) and (eta,eta'$alpha$) nuclear reactions were used, and the predicted amount of helium was consistently about 0.5 of that actually measured. Because there is very little data on helium generation in metals irradiated with high energy neutrons, these results are important and will be related to potential CTR materials. (auth)

It is noted that correction of the coupling resonance, ..nu../sub x/ - ..nu../sub y/ = 0, in intersecting storage accelerators with superconducting magnets requires two families of correcting skew quadrupoles with two independent power supplies. A possible location for the two families is suggested, and results are given for the required strengths of the skew quadrupoles and the required accuracy of the corrections. The results are applied to the ISABELLE storage accelerator.

Design and engineering panameters for the F-144-1 shipping container for transporting FFTF fuel pin bundles or fuel assemblies are presented. (TFD)