Some of the activities in E (Experimental Physics) Division are described. E Division carries out basic and applied research in atomic and nuclear physics as well as in material and biomedical sciences, centered around the Laboratory's four major accelerators. Experiments are grouped under the headings of neutron, photon, and charged-particle interactions. Investigations in this past year involved fission cross sections, nuclear reactions with neutrons, charged particles and gamma rays, integral experiments on neutron and gamma ray transport, fissile materials safeguarding, radiation damage caused by neutrons and protons, dense plasma focus experiments, inner-shell vacancies produced in ion-atom collisions, coherent bremsstrahlung, Raman scattering, and biomedical applications.

U/sub 3/O/sub 8/ recovered as a by-product of the phosphate fertilizer industry may equal 3600-5200 tons by 1985 and represent 7-10 percent of the anticipated annual U.S. demand. If the enormous U.S. phosphate reserves and resources are mined primarily for their uranium content they appear sufficient to fill more than twice the projected cumulative U.S. demand to the year 2000.

A conceptual drawing of the MX experiment is given. The central feature of the MX is a large superconducting magnet. The magnet parameters and conductor parameters are listed. The electrical and engineering design of the magnet is given.

An overview of present operations concerned with the management of Hanford-generated high-level radioactive wastes is presented. Interim storage, leak experience, costs, and program operations are discussed. (LK)

Some new experiments designed to accurately determine the time interval required to produce a reactive event in confined explosives subjected to temperatures which will cause decomposition are described. Geometry and boundary conditions were both well defined so that these experiments on the rapid thermal decomposition of HE are amenable to predictive modelling. Experiments have been carried out on TNT, TATB and on two plastic-bonded HMX-based high explosives, LX-04 and LX-10. When the results of these experiments are plotted as the logarithm of the time to explosion versus 1/T K (Arrhenius plot), the curves produced are remarkably linear. This is in contradiction to the results obtained by an iterative solution of the Laplace equation for a system with a first order rate heat source. Such calculations produce plots which display considerable curvature. The experiments have also shown that the time to explosion is strongly influenced by the void volume in the containment vessel. Results of the experiments with calculations based on the heat flow equations coupled with first-order models of chemical decomposition are compared. The comparisons demonstrate the need for a more realistic reaction model.

The design and fabrication of a test mask suitable for the experimental evaluation of automated integrated circuit photomask inspection systems is described. This mask contains various types and sizes of intentional defects in known locations. The defects are superimposed on a background of images consisting of a typical integrated circuit pattern.

The Field-Reversed-Mirror is a plasma confinement scheme which uses the diamagnetic current of the D-T fuel plasma to convert the open field pattern of a conventional mirror machine into a closed-field pattern with plasma confinement properties which are expected to be considerably improved. If realized, this improvement in confinement will considerably improve the energy gain of the mirror reactor, and result in a reduction in the cost of producing energy. The Field Reversed Mirror device is described and compared with earlier field-reversed configurations, and the overall energy and particle balance relations are given. Based on this, preliminary engineering design calculations of the major components of an FRM reactor are presented. We find that the engineering design leads to simple structures for which reasonably accurate cost estimates are easy to make (circular coils, cylindrical vacuum tanks, etc.). A cost optimization has been performed, and the optimum DT reactor is found to have a fusion output of 23 MW/cell from a plasma radius 5 cm, length 15 cm, in a field of roughly 10 Tesla.

Like toroidal confinement, confinement by a potential barrier offers the possibility of unlimited Q if the barrier is good enough. For a barrier height PHI, approximately tau approximately equal to tau/sub collision/ exp PHI/T/sub i/. These notes review previous ideas about how to establish a potential barrier at the ends of a mirror machine and we also discuss a different possibility using mirror confinement itself to establish a barrier utilizing the positive ambipolar potential characteristic of mirror machines. One example consists of three mirrors in tandem, the two at the ends having a much smaller volume. Then mirror confinement in the end cells would be used to establish ambipolar barriers that stopper up the ends of the central, large mirror cell. An example is discussed in which, by approximate calculation, it appears that ignition might occur in a center cell 10 to 20 meters long and the overall Q is 5 or more, including the power required to sustain the end cells by neutral injection.

BLAST simulates the high temperature gas cooled reactor reheater-steam generator module with a multi-node, fixed boundary, homogenous flow model. The time dependent conservation of energy, mass, and momentum equations are solved by an implicit integration technique. The code contains equation of state formulations for both helium and water as well as heat transfer and friction factor correlations. Normal operational transients and more severe transients such as those resulting in low and/or reverse flow can be simulated. The code calculates helium and water temperature, pressure, flow rate, and tube bulk and wall temperatures at various points within the reheater-steam generator module during the transients. BLAST predictions will be compared with dynamic test results obtained from the Fort St. Vrain reactor owned by Public Service of Colorado, and, based on these comparisons, appropriate improvements will be made in BLAST. BLAST is written in FORTRAN IV for the IBM 360/91 computer at the Oak Ridge National Laboratory.

Microwave rotational spectrometry is a very selective analytical technique for polar gaseous compounds. For some selected molecules (e.g., HN/sub 3/, H/sub 2/CO, SO/sub 2/, etc.) concentrations as low as 100 ppB can be detected by continuously flowing the analyzed gas mixture through the absorption cell. However, some form of preconcentration of the desired species is required for detection limits below 100 ppB. Initial work with various trap materials for ammonia suggests using chromatographic packing material. Specifically, Chromasorb 104 provides an efficient trap and has been found to quantitatively release the ammonia upon slight heating. A preconcentrator/integrator module to thoroughly test the concept of quantitative preconcentration by the method of adsorption-desorption on chromatographic packing materials was constructed. It was used in conjunction with the microwave spectrometer ammonia detector to provide quantitative data of trapping efficiency and reproducibility. The preconcentrator/integrator system is described. (WHK)

A synopsis is given of the detailed characterization of the existing environment at Hanford. The following aspects are covered: demography, land use, meteorology, geology, hydrology, and seismology. It is concluded that Hanford is one of the most extensively characterized nuclear sites. 16 figures. (DLC)

The presence of hydrodynamic fluid instability at the ablation surface puts constraints on the kinds of targets, surface finish, and energy sources that one can use for thermonuclear micro-implosions. If Taylor-like modes grow at near the classical value, one is limited to low aspect ratio shells and surface finishes of 10-100 A. These surface finish requirements can be reduced by 1 to 2 orders of magnitude by exploiting density gradient modification techniques to obtain a shallow density gradient at the ablation surface. For laser driven targets, the gradient is achieved by utilizing suprathermal electrons with a high energy ''get lost'' region to eliminate severe preheat problems. For charged particle sources, the reduction is achieved by introducing an energy spread on the driving source.

The stacking order of the samples in the LLL Rotating Target Neutron Source is given. Neutron fluences calculated for the Nb dosimetry foils are listed. (DLC)

Dielectrophoretic filtration experiments were conducted on glass, polyester, dacron, Teflon, wool, acrylic and polypropylene filter media. A polydispersed (sigma g = 2.0, ammd = 0.95 ..mu.. m) sodium chloride particle was used as a test aerosol. All materials exhibited significant increases in efficiency with increasing field strengths. Efficiencies of greater than 99 percent could be obtained from glass fiber mats using a 13 kV/cm electric field at 16.3 cm/s face velocity.

The total cross section for the reaction K/sup -/p ..-->.. anti K/sup 0/n was measured between 500 and 1050 MeV/c in steps of 10 MeV/c. The experiment was performed at the Brookhaven AGS using a negative kaon beam focused onto a 41 cm long liquid hydrogen target. The target was surrounded by a box of scintillation counters which detected and vetoed all charged final states. The charged particle veto box was in turn surrounded by a box of lead-scintillator sandwich shower counters. These counters detected and vetoed all final states with photons or ..pi../sup 0/'s. The only reaction left unvetoed was K/sup -/p ..-->.. K/sub L/n, the cross section for which is just /sup 1///sub 2/ the K/sup -/p ..-->.. K/sub L/n, cross section. It was necessary to make a number of corrections to the data to account for event losses and inefficient background rejection. The final results have a statistical accuracy of 1% which is an improvement of almost a factor of 10 over previously existing data. An important new feature can be seen in the cross section, a significant shoulder between 825 and 900 MeV/c. Preliminary results from a partial wave analysis including the new data indicate that …

More than 2000 tensile and four-point bend tests were made at ambient temperature on specimens from one log of extruded near-isotropic petroleum-coke-based nuclear graphite (Great Lakes Carbon Corporation grade H-451). The mean strengths showed the expected systematic dependence on orientation and location, with axial specimens stronger than radial specimens and material near the edge of the log stronger than material near the centerline. There were additional local fluctuations in strength which, in some cases, corresponded to local variations in density. The coefficient of variation was lower for axial specimens than for radial specimens, and lower for bend specimens than for tensile specimens. The cumulative strength distribution could be fitted equally well by a normal (Gaussian) distribution or by a Weibull distribution. The value of the Weibull modulus, m, was lower for tensile tests than for bend tests, which conflicts with predictions of the Weibull model for the strength of brittle solids. The mean tensile strength of small tensile specimens (volume 724 mm/sup 3/) was higher than that of large tensile specimens (volume 9847 mm/sup 3/) by 3 percent (axial orientation) or 8 percent (radial orientation). These numbers disagree with differences of 28 percent and 38 percent, respectively, predicted by the …

The energy carried by particles and low energy x-rays resulting from irradiation of targets with .5 to 1 TW, 1.06 ..mu..m lasers has been measured. The energy distributions were obtained from measurements at discrete locations using calorimeters and work is in progress to obtain them over a hemisphere with a thermal imaging system. Azimuthal symmetry and polar distributions for different focusing schemes have been determined. The data have been integrated to obtain the absorbed energy and these values compared to box calorimetry and optical energy balance. The relative emission of low energy x-rays from different Z materials can be obtained by comparing these data to charge collector data. Such comparisons also showed that the effective ion charge can be as low as a factor of two below the completely ionized state. The existence of low charge state ions has since been confirmed with high resolutions spectrometers.

Good seeding and growth were achieved during the past quarter with the Heat Exchanger Method at melt superheats below 10/sup 0/C. To achieve a high enough seeding temperature at low superheat, the heat exchanger was raised one inch higher in the heat zone. For this higher position, seeding conditions had to be re-established since the temperature profile across the diameter of the heat zone was flatter; i.e., the temperature in the middle of the heat zone was closer to the temperature near the heating element. All the boules produced to date have cracked during cool down, regardless of the annealing and cool-down cycle. The cracking appears to be due to the expansion mismatch between the silicon and the silica which are tenaciously bonded together. The tabulation of the heat-exchanger and furnace temperatures for this quarter's runs are presented. (WDM)

Instrumentation has been developed at the Lawrence Livermore Laboratory for measuring subkilovolt x-rays from laser-produced plasmas. This information is needed to do a complete energy balance on laser fusion experiments. The instruments must have thin windows and yet discriminate against the severe environment of other intense target emissions such as ions, electrons, and scattered laser light. Low energy x-ray measurements down to 0.1 keV will be presented using these absolutely calibrated detectors on laser target shots with the LLL Terawatt laser facility, Cyclops. Precautions in using these detectors in a laser fusion target chamber will be enumerated from our experience in using these instruments on hundreds of laser shots.

Switching and power supply problems of neutral atom beam injection systems and superconducting magnets are briefly discussed. Typical power supplies for both systems are described.

In recent years several techniques have become available to characterize the structure and chemical composition of surfaces of ceramic materials. These techniques utilize electron scattering and scattering of ions from surfaces. Low-energy electron diffraction is used to determine the surface structure, Auger electron spectroscopy and other techniques of electron spectroscopy (ultraviolet and photoelectron spectroscopies) are employed to determine the composition of the surface. In addition the oxidation state of surface atoms may be determined using these techniques. Ion scattering mass spectrometry and secondary ion mass spectrometry are also useful in characterizing surfaces and their reactions. These techniques, their applications and the results of recent studies are discussed. 12 figures, 52 references, 2 tables.

The Possell bladeless turbine was tested at the LLL Geothermal Test Facility to evaluate its potential for application in the total flow process. Test description and performance data are given for 3000, 3500, 4000, and 4500 rpm. The maximum engine efficiency observed was less than 7 percent. It is concluded that the Possell turbine is not a viable candidate machine for the conversion of geothermal fluids by the total flow process. (LBS)

Thermodynamic studies are of interest for any chemically reacting system. Thermodynamics constitute the limiting cases for kinetically reacting systems. In many systems, as a result of the exponential nature of most chemical reactions (reaction rate = k Ae/sub -..delta..H/RT/), reactions of interest occur over a fairly narrow temperature region. At lower temperatures, reaction rates are negligible, while at higher temperatures the reaction can be so rapid as to be controlled either by thermodynamics or mass transfer. Thus, thermodynamic equilibrium at a characteristic temperature can often be a close approximation to a kinetic system. Previous work by Stephens in the coal-water-oxygen thermodynamic system is extended. Results with 20 percent combustion and amorphous carbon are shown to be a good approximation to kinetic data. Experimental Lurgi coal gasification data are closely approximated by a calculated thermodynamic temperature of 1060 K. This temperature is used to show that for underground coal gasification with a constant oxygen/coal ratio, optimum steam/oxygen ratios should be as low as possible. Probably the steam/oxygen ratio should exceed 3.6 to avoid slagging of the ash. At this ratio, about twice as much methane can be obtained in comparison to the Lurgi ratio of 7.7. (auth)

A preliminary set of experiments was conducted in order to determine the sorptive characteristics of rock with respect to ionic species under conditions of dynamic flow of an aqueous solution through a rock core. The results of the dynamic experiments have been compared to the results of static or batch experiments which were conducted under corresponding physical and chemical conditions. It was found that, gram for gram, sorption of the ion of interest was always greater in the dynamic experiments. These results are contrary to early predictions and indicate that the effect of rock surface area on adsorption was overshadowed by another parameter. It has been suggested as a working hypothesis that the competitive effect of ions that were dissolved and/or leached from the rock in batch experiments has resulted in reduced sorption of the ion of interest. If the hypothesis is confirmed by further experimental work, a ramification of the study is that calculations concerning transport of radioactivity in groundwater which utilize input parameters derived from static tests will tend to be conservative with respect to what occurs in nature. (auth)