We investigate the stability of a static, infinitely long and straight vacuum string solution under inhomogeneous axisymmetric time-dependent perturbations. We find it to be perturbatively stable. We further extend our work by finding a string solutions in an expanding Universe. The back reaction of the string on the gravitational field has been ignored. The background is assumed to be a Friedman-Robertson-Walker (FRW) cosmology. By numerically integrating the field equations in a radiation and matter dominated models, we discover oscillatory solutions. The possible damping of these oscillations is discussed. For late times the solution becomes identical to the static one studied in the first part of the paper. 19 refs., 8 figs.

An analytic model is developed and used to study the phenomenon of flow reversal which is observed in two-dimensional simulations of divertor plasmas. The effect is shown to be caused by the radial spread of neutral particles emitted from the divertor target which can lead to a strong peaking of the ionization source at certain radial locations. The results indicate that flow reversal over a portion of the width of the scrape-off layer is inevitable in high recycling conditions. Implications for impurity transport and particle removal in reactors are discussed.

The plasma described in this report is generated by a 15 to 34 kV ion beam, consisting primarily of protons, passing through an H/sub 2/ gas cell neutralizer. Plasma ions (or ion-electron pairs) are produced by electron capture from (or ionization of) gas molecules by beam ions and atoms. An explanation is provided for the observed anomalous behavior of the electron temperature (T/sub e/): a step-lite, nearly two-fold jump in T/sub e/ as the beam current approaches that which minimizes beam angular divergence; insensitivity of T/sub e/ to gas pressure; and the linear relation of T/sub e/ to beam energy.

Drillhole DOE-2 was drilled to investigate a structural depression marked by the downward displacement of stratigraphic markers in the Salado Formation. Contrary to several hypotheses, halite layers were thicker in the lower part of the Salado, not thinner as a result of any removal of halite. The upper Castile anhydrite in Drillhole DOE-2 is anomalously thick and is strongly deformed relative to the anhydrite in adjacent drillholes. In contrast, the halite was <8 ft thick and significantly thinner than usually encountered. The lower Castile anhydrite appears to be normal. The depression within the correlated marker beds in the Salado Formation in Drillhole DOE-2 is interpreted as a result of gravity-driven deformation of the underlying Castile Formation. Several stratigraphic units were hydrologically tested in Drillhole DOE-2. Testing of the unsaturated lower portion of the Dewey Lake Red Beds was unsuccessful because of exceptionally small rates of fluid intake. Drill-stem tests were conducted in five intervals in the Rustler Formation, over the Marker Bed 138-139 interval in the Salado formation, and over three sandstone members of the Bell Canyon Formation. A pumping test was conducted in the Culebra Dolomite Member of the Rustler Formation. Pressure-pulse tests were conducted over the entire Salado …

This document shows analytic solutions to the problem of contaminant dispersion from an array of point sources in a waste disposal site. These solutions are for waste sources in a fluid-saturated porous medium, and may be for isotropic or anisotropic dispersion. The solutions are illustrated through isopleths of contaminants for a planar array of point sources perpendicular to ground-water flow. The concentration fields several meters away from this plane can be approximated by equivalent plane sources. 2 refs., 4 figs.

The J-vector x B-vector forces associated with the surface current of a plasma-filled ion diode will accelerate this plasma fill toward the anode surface. It is well known that such a configuration with a high I is susceptible to the hydromagnetic Rayleigh-Taylor instability in certain geometries. A number of ion diode plasma sources have been proposed, most of which have a falling density going away from the wall. A somewhat more unstable case, however, is that of uniform density. In this report we attempt to establish an upper limit on this effect with a simple analytic model in which a uniform-density plasma is accelerated by the magnetic field anticipated in a PBFA-II diode. We estimate the number of linear e-foldings experienced by an unstable surface as well as the most damaging wavelength initial perturbation. This model, which accounts approximately for stabilization due to field diffusion, suggests that even with a uniform fill, densities in excess of a few 10/sup 15/ are probably not damaged by the instability. In addition, even lower densities might be tolerated if perturbations near the most damaging wavelength can be kept very small.

During Fiscal Years 1986 and 1987, Pacific Northwest Laboratory (PNL) achieved several major milestones: (1) a Site Access Agreement with San Diego Gas and Electric Company was signed and since renewed for Fiscal Year 1987; (2) the PNL field laboratory was moved from East Mesa to the Heber Binary Plant; (3) a subcontract was let to a commercial supplier of pH probes to build advanced transistor-based pH sensors; (4) a field test determined response of the transistor-based pH probes to Heber brines; (5) a filter test was performed to look at scaling tendencies of the Heber plant brine if it were cooled below 150/sup 0/F; and (6) two prototype particle counters based on ultrasonic sound and a laser beam scattering were tested in the laboratory and subjected to one field test.

The Twentieth Annual LAMPF Users Group Meeting was held October 27-28, 1986, at the Clinton P. Anderson Meson Physics Facility. The program included a number of invited talks on various aspects of nuclear and particle physics as well as status reports on LAMPF and discussions of upgrade options. The LAMPF working groups met and discussed plans for the secondary beam lines, experimental programs, and computing facilities. Individual papers have been cataloged separately.

Issues addressed were the adequacy of the data for the various models, effectiveness of the models to represent the data, particular information provided by the models, the role of caisson experiments in providing fundamental knowledge of porous-media water flow and solute transport, and the importance of geochemistry to the transport of nonconservative tracers. These proceedings include the presentations made by each of the modelers; the summary document written by the panel; and a transcript of the discussions, both the discussions that followed individual presentations and the general discussion held on the second day. This publication completes the series on the workshop. Volume I in the series (NUREG/CR-4615, Vol. I) contains background information and the data sets provided each modeler.

A much improved version of our gas-filled spectrometer for heavy-ion-induced fusion reactions is described. This instrument (SASSY II) is of the type D-Q-D wherein the dipoles are made with strong vertically-focussing gradients. The problems associated with experiments with cross sections in the picobarn range are discussed. In such experiments, it is necessary to identify single atoms with a high degree of confidence.

A scheme was developed for the determination of oxidation states of plutonium in environmental samples. The method involves a combination of solvent extractions and coprecipitation. It was tested on solutions with both high-level and trace-level concentrations. The scheme was used to determine Pu oxidation states in solutions from solubility experiments in groundwater from a potential nuclear waste disposal site. At steady-state conditions, Pu was found to be soluble predominantly as Pu(V) and Pu(VI).

An overview of the present capabilities of the NSLS 750 MeV VUV ring and the 2.5 GeV x-ray ring is presented. Emphasis is placed on performance of the now operational facility, the efforts to improve this performance, a description of the ''Phase II'' upgrade, and outlook for the future.

The Initial Engine Test Decommissioning Project is described in this report. The Initial Engine Test facility was constructed and operated at the National Reactor Testing Station, now known as the Idaho National Engineering Laboratory, to support the Aircraft Nuclear Propulsion Program and the Systems for Nuclear Auxiliary Power Transient test program, circa 1950 through 1960s. Due to the severe nature of these nuclear test programs, a significant amount of radioactive contamination was deposited in various portions of the Initial Engine Test Facility. Characterizations, decision analyses, and plans for decontamination and decommissioning were prepared from 1982 through 1985. Decontamination and decommissioning activities were performed in such a way that no radiological health or safety hazard to the public or to personnel at the Idaho National Engineering Laboratory remains. These decontamination and decommissioning activities began in 1985 and were completed in 1987. 13 figs.

This paper is targetted at personnel who have the responsibility of designing the radiation shielding against neutron fluences created when protons interact with matter. Shielding of walls and roofs are discussed, as well as neutron dose leakage through labyrinths. Experimental data on neutron flux attenuation are considered, as well as some calculations using the intranuclear cascade calculations and parameterizations.

Degassing of the TFTR graphite limiter by low density deuterium or helium discharges enables the limiter to pump deuterium, thereby reducing recycling and improving energy confinement in neutral-beam-heated discharges. During a helium degassing sequence the hydrogen influx decreased by a factor of 20. As a consequence of degassing sequences the low density limit in 0.8 mA deuterium discharges decreased from 1 x 10/sup 19/ m/sup -3/ to 0.5 x 10/sup 19/ m/sup -3/, the density-decay time dropped from greater than 10 s to 0.15 s, and the recycling coefficient dropped from nearly 1 to less than 0.4. Z/sub eff/ values in 2.2 MA L-mode discharges on the toroidal limiter with neutral-beam-heating power up to 15 MW are between 2 and 3 if the pre-beam plasma has low Z/sub eff/ (high density), but can be as high as 4.5 if the pre-beam target has high Z/sub eff/ (low density). Z/sub eff/ values in enhanced confinement shots drop from 7 during the ohmic phase to 3 with neutral beam heating. The radiated power drops from 60 to 70% of total heating power to 30 to 35% for beam powers from 10 to 20 MW.

Medicine Lake Volcano, a broad shield volcano about 50 km east of Mount Shasta in northern California, produced rhylotic eruptions as recently as 400 years ago. Because of this recent activity it is of considerable interest to producers of geothermal energy. The USGS and LLNL conducted an active seismic experiment designed to explore the area beneath and around the caldera. This experiment had two purposes: To produce high-quality velocity and attenuation images of the young magma body presumed to be the source for the young volcanic features, and to collect a dataset that can be used to develop and test seismic imaging methods that may be useful for understanding other geothermal systems. Eight large explosions were detonated in a 50 km radius circle around the volcano, a distance chosen to produce strong upward traveling signals through the area of interest. The data were inverted using Aki's method to produce three-dimensional velocity and attenuation images of the sub-surface. Preliminary interpretation shows low velocity and attenuation on the flanks of the volcano, and coincident high attenuation values and low velocities (-20%) from 3 to 5 km beneath the center of the caldera. This zone may be a region of partial melt which …

The technologies available for vertex detection and the restrictions imposed by event topologies and multiple coulomb scattering are discussed. It is shown that ultimate performance limits for collider detectors are set by how close active detection starts relative to the interaction region. This in turn is determined by the machine characteristics and the care taken to provide collimation and shielding to minimize radiation backgrounds.

Two Geothermal Technology Division (GTD)-sponsored programs: (1) Geothermal Materials Development, and (2) Advanced Biochemical Processes for Geothermal Brines, are described. In the former, work in the following tasks is in progress: (1) high temperature elastomeric materials for dynamic sealing applications, (2) advanced high temperature (300/sup 0/C) lightweight (1.1 g/cc) well cementing materials, (3) thermally conductive composites for heat exchanger tubing, (4) corrosion rates for metals in brine-contaminated binary plant working fluids, and (5) elastomeric liners for well casing. Methods for the utilization and/or the low cost environmentally acceptable disposal of toxic geothermal residues are being developed in the second program. This work is performed in two tasks. In one, microorganisms that can interact with toxic metals found in geothermal residues to convert them into soluble species for subsequent reinjection back into the reservoir or to concentrate them for removal by conventional processes are being identified. In the second task, process conditions are being defined for the encapsulation of untreated or partially biochemically treated residues in Portland cement-based formulations and the subsequent utilization of the waste fractions in building materials. Both processing methods yield materials which appear to meet disposal criteria for non-toxic solid waste, and their technical and economic feasibilities …

Initially, the goal of this report is to compare and contrast penetration rates of rotary-mud drilling and core drilling in young volcanic terranes. It is widely recognized that areas containing an abundance of recent volcanic rocks are excellent targets for geothermal resources. Exploration programs depend heavily upon reliable subsurface information, because surface geophysical methods may be ineffective, inconclusive, or both. Past exploration drilling programs have mainly relied upon rotary-mud rigs for virtually all drilling activity. Core-drilling became popular several years ago, because it could deal effectively with two major problems encountered in young volcanic terranes: very hard, abrasive rock and extreme difficulty in controlling loss of circulation. In addition to overcoming these difficulties, core-drilling produced subsurface samples (core) that defined lithostratigraphy, structure and fractures far better than drill-chips. It seemed that the only negative aspect of core drilling was cost. The cost-per-foot may be two to three times higher than an ''initial quote'' for rotary drilling. In addition, penetration rates for comparable rock-types are often much lower for coring operations. This report also seeks to identify the extent of wireline core drilling (core-drilling using wireline retrieval) as a geothermal exploration tool. 25 refs., 21 figs., 13 tabs.

The US Subseabed Disposal Program has compiled an extensive concentration factor and biological half-life data base from the international marine radioecological literature. A microcomputer-based data management system has been implemented to provide statistical and graphic summaries of these data. The data base is constructed in a manner which allows subsets to be sorted using a number of interstudy variables such as organism category, tissue/organ category, geographic location (for in situ studies), and several laboratory-related conditions (e.g., exposure time and exposure concentration). This report updates earlier reviews and provides summaries of the tabulated data. In addition to the concentration factor/biological half-life data base, we provide an outline of other published marine radioecological works. Our goal is to present these data in a form that enables those concerned with predictive assessment of radiation dose in the marine environment to make a more judicious selection of data for a given application. 555 refs., 19 figs., 7 tabs.

Results from a series of hydrostatic and triaxial compression tests which were performed on polyurethane foams are presented in this report. These tests indicate that the volumetric and deviatoric parts of the foam behavior are strongly coupled. This coupling behavior could not be captured with any of several commonly used plasticity models. Thus, a new constitutive model was developed. This new model was based on a decomposition of the foam response into two parts: (1) response of the polymer skeleton, and (2) response of the air inside the cells. The air contribution was completely volumetric. The new constitutive model was implemented in two finite element codes, SANCHO and PRONTO. Results from a series of analyses completed with these codes indicated that the new constitutive model captured all of the foam behaviors that had been observed in the experiments. Finally, a typical dynamic problem was analyzed using the new constitutive model and other constitutive models to demonstrate differences between the models. Results from this series of analyses indicated that the new constitutive model generated displacement and acceleration predictions that were between predictions obtained using the other models. This result was expected. 9 refs., 45 figs., 4 tabs.

In the Long Valley caldera, an area of recently (approx.550 y) active volcanism and current seismic activity, /sup 222/Rn concentrations in hot, warm, and cold spring waters have been measured since 1982. Rn contents of the waters correlate inversely with temperature and specific conductance, with high concentrations (1500 to 2500 pCi/l) occurring in dilute cold springs on the margins of the caldera, and low concentrations (12 to 25 pCi/l) in hot to boiling springs. Rn correlates only slightly with the uranium contents of the wide range of rocks which host the hydrological system feeding the springs. These environmental effects on the radon record may mask responses to small or distant seismic, volcanic, or crustal deformation events. To date, anomalous changes in water-borne Rn have been observed in connection with at least one earthquake, which occurred close to the monitoring site. This continuing study points out that an understanding of the geological setting, its associated hydrological system, and environmental influences is necessary to properly evaluate concentrations and changes in groundwater radioactivity.

Experimental measurements of sin/sup 2/theta/sub W/ are surveyed. They are shown to test electroweak unification at the quantum loop level and constrain new physics beyond the standard model. Neutrino oscillations are also examined in the framework of 3 generation mixing. Searches for nu/sub ..mu../ ..-->.. nu/sub tau/ oscillation at aceelerator facilities are advocated.

A simulated space environment test of a flight prototypic SP-100 reactor, control system, and flight shield will be conducted at the Hanford Engineering Development Laboratory (HEDL). The flight prototypic components and the supporting primary heat removal system are collectively known as the Nuclear Assembly Test Article (TA). The unique configuration and materials of fabrication for the Test Article require a specialized handling facility to support installation, maintenance, and final disposal operations. Westinghouse Hanford Company, the Test Site Operator, working in conjunction with General Electric Company, the Test Article supplier, developed and evaluated several handling concepts resulting in the selection of a reference Test Article Handling System. The development of the reference concept for the handling system is presented.