A brief parametric survey of the x-ray characteristics of a gold micro-disk irradiated at 3 x 10/sup 14/ watt/cm/sup 2/ by a 1 nsec Nd-glass laser pulse has been provided as an example of a laser generated bright x-ray source. It was shown that a simple phenomenological model of the laser generated x-ray source as a microscopic equilibrium plasma radiating as a blackbody for a finite time determined by its hydrodynamic disassembly and radiation losses, serves to provide an adequate approximation to the x-ray characteristics of such sources. The current state of x-ray microscopy within the LLL laser fusion program was briefly reviewed. Kirpatrick--Baez grazing incidence reflection x-ray microscopes are being used to provide 3 to 5 ..mu..m resolution, broadband images (..delta..E/E approx. 0.3) over a spectral range from .6 keV to 3.5 keV. Zone Plate Coded Imaging is used to provide 5 to 10 ..mu..m resolution, broadband (..delta..E/E approx. 0.5) images over a spectral range from 3 keV to 50 keV. Efficient x-ray lensing elements with anticipated submicron resolution are being developed for narrowband (..delta..E/E approx. 10/sup -2/) imaging applications over a spectral range .1 keV to 8 keV. The x-ray lens design is that of a transmission blazed …

Sections of the 40-kV, 40-A, TMX source are shown. This module is comprised of the arc chamber and accelerator sections. The source accelerator section uses a single rectangular insulator to perform three functions: providing voltage standoff, forming the supporting structure, and acting as the vacuum wall. Both machinable glass ceramic (Corning Macor/sup TM/) and F.R.P. (Nema G-10) have been used for this insulater. In either case, the insulator is joined to the titanium base plate and extractor electrode by thermal-setting-epoxy adhesive. The parts are self jigging; the bonding is done at 120 to 130 /sup 0/C under a load of .34 MPa (50 psi).

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A design for water-cooled extractor grids for long-pulse and continuously operated ion sources for neutral-beam injectors is described. The most serious design problem encountered is that of minimizing the thermal deformation (bowing) of these slender grid rails, which have typical overall spans of 150 mm and diameters on the order of 1 mm. A unique U-tube design is proposed that offers the possibility of keeping the thermal bowing down to about 0.05 mm (about 2.0 mils). However, the design requires high-velocity cooling water at a Reynolds number of about 3 x 10/sup 4/ and an inlet pressure on the order of 4.67 x 10/sup 6/ Pa (677 psia) in order to keep the axial and circumferential temperature differences small enough to achieve the desired small thermal bowing. It appears possible to fabricate and assemble these U-tube grids out of molybdenum with high precision and with a reasonably small number of brazes.

Flat plate chord tests are one experimental method used to investigate how fluid/structure interaction (FSI) effects modify the impulsive loading in nuclear reactor pressure suppression pools. This analytical study examines the applicability of using a flexible flat plate in an otherwise rigid shell to model dynamic pool wall response in a flexible shell pressure suppression torus. Bubble pressures varying by a factor of seven are used as input to two-dimensional finite-element models. Boundary response to various plate and shell thicknesses are compared on the basis of equivalent natural frequency. Results indicate the qualitative flat plate response compares well with the flexible shell but absolute pressures vary significantly and nonconservatively.

An automated system for the performance of ion-exchange chromatography with corrosive solvents has been built. It is LSI-II microcomputer controlled and is capable of selecting six sample/solvents and collecting six separate fractions. Preliminary results on the separation of plutonium from 8M HNO/sub 3/ solutions indicate that the system can achieve chemical yields, analytical accuracy, and precision fully comparable to manual column operation at a considerable savings of operator time.

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Several nonlinear effects which limit Brillouin and Raman scatter of intense light in large underdense plasmas are examined. After briefly considering ion trapping and harmonic generation, we focus on the self-consistent ion heating which occurs as an integral part of the Brillouin scattering process. In the long-term nonlinear state, the ion wave amplitude is determined by damping on the heated ion tail which self-consistently forms. A simple model of the scatter is presented and compared with particle simulations. A similar model is also applied to Raman scatter and compared with simulations. Our calculations emphasize that modest tails on the electron distribution function can significantly limit instabilities involving electron plasma waves.

On the basis of time-integrated emittance measurements, several different types of field emitter diodes were characterized at 1 to 3 kA, 1 MeV. These measurements were part of the design effort for the injector system of a linear induction accelerator, to be used as a flash x-ray source at Lawrence Livermore Laboratory. The experimental parameters were the cathode type, the anode mesh texture, the diode spacing and voltage, and the level of collimation of the emerging beam. Experimental results are presented that show that over a wide range, the emittance was proportional to the level of collimation. For any one diode, with the spacing left fixed, the emittance was found to be essentially independent of the diode voltage and current. Differential focusing of different energy beam components affects most strongly the peripheral components of the beam, and strong collimation was found to minimize the effects of momentum spread on the emittance. The lowest emittances (30 to 40 mr-cm at 400 A) were obtained with a foil-type cathode in a ball-over-plane configuration, using an etched tungsten mesh anode, and collimating the beam to one quarter of the total current.

There are nine different systems requiring over fifty computers in the Local Control and Instrumentation System for the Mirror Fusion Test Facility. Each computer system consists of an LSI-11/2 processor with 32,000 words of memory, a serial driver that implements the CAMAC serial highway protocol. With this large number of systems it is important that as much software as possible be common to all systems. A serial communications system has been developed for data transfers between the LSI-11/2's and the supervisory computers. This system is based on the RS 232 C interface with modem control lines. Six modem control lines are used for hardware handshaking, which allows totally independent full duplex communications to occur. Odd parity on each byte and a 16-bit checksum are used to detect errors in transmission.

To successfully develop the geothermal resources of the Imperial Valley, adequate supplies of cooling water must be obtained. The primary sources of water include waste waters from agricultural lands, condensate from flashed-steam facilities, and irrigation water. The major advantages and disadvantages of these supplies are examined and then the consequences of adopting six sets of water policies to support three scenarios of geothermal energy production are assessed. The assessment includes analyses of potential constraints to development as a result of restrictive water policies. It also includes predictions of changes in the Salton Sea's elevation and salinity caused by the consumption of agricultural drain water for cooling.

A single electrostatic wave in a magnetoplasma causes stochastic ion motion in several physically different situations. Various magnetic fields (uniform, tokamak, and mirror) and various propagation angles with respect to the field have been studied. A brief review of this work shows that all situations can be understood using the concept of overlapping resonances. Analytical calculations of the wave amplitude necessary for stochasticity have been carried out in some cases and compared with computer and laboratory experiments. In the case of an axisymmetric mirror field the calculations predict stochastic motion of ions with energy below a threshold that depends weakly on the wave amplitude and on the scale lengths of the magnetic field. Studies with an azimuthally asymmetric field show that the asymmetry causes substantial changes in the motion of some ions.

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Using a pair of lasers near 6000 A, the J = 6 ground state is excited to a J = 6 intermediate level and then to a J = 5 upper state. Non-resonant fluorescences from both excited states are separately detected. Results of a set of model calculations are tabulated. Level 3 average populations are always very small, since the system decays rapidly into inaccessible metastable states. This means that chemistry experiments are difficult. The differences between parallel and perpendicular polarization are modest. The fluorescence dips converge to a value near 50%. The level 3 populations do not approach a common value. This means that the most reliable experimental measurement does not determine the level populations. The most striking changes appear in the last two, most exact, models. The difference between the models is that one includes, for the first time, the linear frequency chirp produced by the fanlike spread of the focussed laser beams. This seemingly innocuous change halves the population left in the ground state. It appears that analogues of adiabatic passage and adiabatic rapid passage respectively are being observed.

A rapid and reliable method for analyzing technetium-99 in a wide variety of environmental samples, including waters, soils, stream sediments, and vegetations, has been developed. The procedure entails oxidizing the technitium to the heptavalent state and dissolving it in 6 N sulfuric acid. From that medium the technetium is quantitatively and selectively extracted into tributyl phosphate. A portion of the extract is then added to a scintillation cocktail, and technetium-99 activity is measured by liquid scintillation counting. Since a relatively large sample can be handled, the method can detest as little as 0.016 pCI /sup 99/Tc/ml water, 0.1 pCi /sup 99/Tc/g soil or sediment, and 0.2 pCi /sup 99/Tc/g vegetation. The procedure has also been adapted to analyzing urine samples, in which technetium activity as low as 0.12 pCi/ml can be detected.

Leach rates for /sup 237/Np and /sup 239/Pu are investigated with a single-pass leaching system. The factorial experimental design uses several combinations of solution composition and flow rate, and two temperatures, 25 and 75/sup 0/C. The 25/sup 0/C results are compared with those from a modified IAEA procedure. At 25/sup 0/C, leach rates decrease with time. Agreement between results from the single-pass and modified IAEA methods is fair with WIPP brine leachant, good with NaHCO/sub 3/, and good with distilled H/sub 2/O. Leach rates are approximately independent of flow rates at room temperature, but increase with flow rates at high temperature. Rates for /sup 237/Np increase with temperature, but those for /sup 239/Pu either decrease or do not change with temperature. 7 figures.