The ECRH diagnostics system monitors the net power delivered to the plasma by four 200-kW gyrotron oscillators, the frequency of each gyrotron, and some operating parameters of the gyrotron power supply system. The combination CAMAC- and GPIB-based data acquisition system is under desktop computer control that provides the capability for data conversion and display. The data acquisition system is also interfaced to the main computer system that acquires and archives the data.

The giant planets - Jupiter, Saturn, Uranus, and Neptune - differ markedly from the inner, or terrestrial, planets. Observations of their average density, gravitational moments, and atmospheric composition have enabled astrophysicists to draw some conclusions as to their structure, but efforts have been hampered by a lack of accurate data on the chemical, physical, and thermodynamic properties of constituent materials at the extremely high temperatures and pressures characteristic of planetary interiors. Shock-wave experiments conducted recently at LLNL have provided more accurate equations of state and electrical conductivities for many of these materials, and these have led to improved structural models of the giant planets.

This paper describes an analytical tool for evaluating the effectiveness of safeguards that protect special nuclear material (SNM). The tool quantifies the effectiveness using several measures, including probabilities and expected times to detect and respond to malevolent attempts against the facility. These measures are computed for a spectrum of threats involving outsiders, insiders, collusion, falsification, and deceit. Overall system effectiveness is judged using performance indices aggregated over all threats. These indices can be used by designers and regulators when comparing costs and benefits of various safeguards. The framework is demonstrated with an example in which we assess vulnerabilities of a safeguards system and identify cost-effective design modifications.

A one-dimensional Lagrangian calculation of the implosion of a hydrogen gas puff is presented. At maximum compression, 60% of the mass is located in a density spike .5 mm off the axis with a half width of 40 ..mu..m. The temperature on axis reaches 200 eV.

The High-Field Test Facility (HFTF) project has two primary goals. The first is to establish manufacturing capability for a Nb/sub 3/Sn conductor suitable for use in a mirror fusion coil. The second is to provide a test facility for evaluating other fusion conductor designs at high fields. This paper describes some of the problems encountered and the solutions devised in working toward the first goal. Construction of the test facility coils will be described in a subsequent paper.

The twenty-three (23) MFTF sustaining neutral beam arc power supplies were designed to provide 0.3 to 30 second output pulses over a range of 24 to 71 volts and 600 to 4000 amperes at 10 percent duty. For economic reasons, the circuit design consists of a 12 pulse rectifier which is asynchronously switched on and off by a three phase electromechanical contactor in the primary ac input. The paper describes the analysis of the problem, various possible solutions considered, and the simple and inexpensive solution adopted for use.

The backscattering of energetic hydrogen particles, 1-1000 eV, from alkali metal surfaces provides for a relatively large yield of negative hydrogen ions. These yields are enhanced by particle reflection from surfaces consisting of partial alkali coatings over high-Z transition-metal substrates. The theoretical data supporting these observations are reviewed. The parameters leading to optimum reflection yields are summarized. In the volume of a hydrogen discharge with electron temperatures of about one electron volt, negative ions are formed by dissociative attachment to vibrationally excited molecules. The vibrational distribution is determined by e-V collisions between low energy electrons and vibrationally excited molecules, E-V singlet electron excitation processes caused by high energy (100 eV) electrons colliding with ground state molecules exciting to electronic states followed by radiative decay to higher vibrational levels, and V-T collisions between molecules resulting in transfer of vibrational excitation to translational energy. The role of these different processes as they bear on the vibrational distribution is discussed. The possibility of a volume-surface interaction leading to a high volume density of negative ions is considered.

The High-Field Test Facility (HFTF) being built at Lawrence Livermore National Laboratory (LLNL) consists of a set of four Nb-Ti coils, inside of which there is a pair of multifilamentary Nb/sub 3/Sn coils. The outer coils are designed to generate 8 T in the 1-m bore; the Nb/sub 3/Sn coils will boost this to 12 T in a 40-cm bore. This paper describes the first operation of the complete set of Nb-Ti coils and describes and gives results from the data acquisition and analysis system that was used during the test.

This paper describes a new approach for implementing personnel safety interlocks logic using industrial-type programmable controllers. The logic for all personnel safety interlocks except those totally internal to a subsystem is implemented in two non-redundant controllers. A high degree of fail-safe reliability is achieved by augmenting the protective features intrinsic to each controller with those provided by a small amount of external support hardware. The controllers are interfaced to the host computer system via fiber optic data links to enable display of interlock and overall system status on the control room graphic displays. When fully implemented, the controllers will perform the equivalent of over 2000 discreet relay functions.

Four sources or error (uncertainty) are studied in water content obtained from neutron logs calibrated in partially saturated media for holes up to 3 m. For this calibration a special facility was built and an algorithm for a commercial epithermal neutron log was developed that obtains water content from count rate, bulk density, and gap between the neutron sonde and the borehole wall. The algorithm contained errors due to the calibration and lack of fit, while the field measurements included uncertainties in the count rate (caused by statistics and a short time constant), gap, and density. There can be inhomogeneity in the material surrounding the borehole. Under normal field conditions the hole-size-corrected water content obtained from such neutron logs can have an uncertainty as large as 15% of its value.

The present paper represents the first effort to date in which a combined experimental and theoretical approach has been used to study the effects of several inhibitors on hydrocarbon-air flames. This work is part of an attempt to build a consistent picture of chemical kinetic flame inhibition, beginning with a simple halogen molecule such as HBr and progressing sequentially towards more complex and more practical inhibitors such as CF/sub 3/Br. Inhibition efficiency can be defined as the rate of flame speed reduction, the amount of flame speed change per unit inhibitor added. Both the numerical model and the flame tube measurements found that the inhibition efficiency gradually decreases as the amount of inhibitor is increased. The present experimental and modeling results are shown, together with earlier data for CF/sub 3/Br-CH/sub 4/-air and CF/sub 3/Br-C/sub 3/H/sub 8/-air as well as HBr-CH/sub 4/-air, CH/sub 3/Br-CH/sub 4/-air and CF/sub 3/Br-CH/sub 4/-air. In the numerical study it was found that a stoichiometric methane-air mixture with up to 8% methyl bromide could support a flame, propagating at a speed of about 5 cm/sec, even though the addition of the first 1% of CH/sub 3/Br had reduced the flame speed from 38 cm/sec to about 26 …

An S-1 optical streak camera with 10-ps (optical) temporal resolution simultaneously records reflected 1.06-..mu..m laser light and suprathermal (> 30 keV) x rays from laser fusion targets. To make these measurements, the camera x-ray sensitivity is increased 30-fold without significant loss of temporal resolution by increasing the effective slit width from the normal 50 ..mu..m to 1500 ..mu..m. The measurement system is described and sample data are presented.

Topics discussed include thrashing in an RSX11M system - what to do; using solid state disk emulators as the swapping device - performance improvement, performance measurement techniques; capacity planning; bis buffering; and DECNET-11M optimization - performance that can be expected for real environments.

A system has been developed to perform neutron radiographic analysis of dynamic events having a duration of several milliseconds. The system has been operated in the range of 2000 to 10,000 frames/second. Synchronization has provided high-speed-motion neutron radiographs for evaluation of the firing cycle of 7.62 mm munition rounds within a steel rifle barrel. The system has also been used to demonstrate the ability to produce neutron radiographic movies of two-phase flow. The equipment uses the Oregon State University TRIGA reactor capable of pulsing to 3000 MW peak power, a neutron beam collimator, a scintillator neutron conversion screen coupled to an image intensifier, and a 16 mm high speed movie camera. The peak neutron flux incident at the object position is approximately 4 x 10/sup 11/ n/cm/sup 2/s with a pulse, full width at half maximum, of 9 ms. Special studies have been performed on the scintillator conversion screens and on the effects of statistical limitations on the image quality. Modulation transfer function analysis has been used to assist in the evaluation of the system performance.