An efficient, scalable, parallel algorithm for treating contacts in solid mechanics has been applied to interactions between particles in smooth particle hydrodynamics (SPH). The algorithm uses three different decompositions within a single timestep: (1) a static FE-decomposition of mesh elements; (2) a dynamic SPH-decomposition of SPH particles; (3) and a dynamic contact-decomposition of contact nodes and SPH particles. The overhead cost of such a scheme is the cost of moving mesh and particle data between the decompositions. This cost turns out to be small in practice, leading to a highly load-balanced decomposition in which to perform each of the three major computational states within a timestep.

Ion-beam driven hohlraum targets were designed to absorb the energy of PBFAII lithium ion beams within a foam, which converted the ion beam energy into x-rays. The foam was held within a gold hohlraum. X-ray radiation was observed from the top of the target through a circular diagnostic aperture. On the bottom of the target was a gold-coated aluminum witness plate, which was a component of an active, shock-breakout diagnostic. Surrounding the outside of the hohlraum were five titanium pins which produced ion-induced inner-shell x-rays (4.5 keV) to diagnose the lithium beam. Several different manufacturing processes and characterization techniques were utilized to prepare these targets. Extensive documentation provided quality control on their preparation. This report summarizes the preparation, characterization, and documentation of targets for ion-beam driven hohlraum experiments.

The significance of cyclotron radiation losses in next-generation tokamaks depends on the reflectivity of first wall materials. An experimental study of the effective reflectivity for electron cyclotron frequencies in the graphite-walled DIII-D tokamak is reported. Measurements of optically-thin harmonics ({omega} = n{omega}{sub ce}, n > 4) are made for two polarizations from thermal plasma discharges using an absolutely calibrated Michelson interferometer. The reflectivity r and polarization transfer fraction p are obtained by matching measured spectra to simulations from an ECE radiation transport code with adjustable wall parameters. For the frequency range 150-400 GHz average values of r = 0.76 and p = 0.19 are found.

We present the results of the searches for new phenomena in pp collisions at {radical}s=1.8 TeV with the CDF detector using the full data sample of 110 pb{sup -1} collected between 1992 and 1995. We have searched for new physics in events with two photons, testing some of the hypotheses proposed to explain the appearance of the CDF ee{gamma}{gamma} E{sub T} event. New results on the search for a heavy neutral scalar object, charged Higgs bosons (H{sup {+-}}) and the scalar top quark are presented. Finally we summarize the CDF results on the search for third generation leptoquarks.

State-of-the-art in multi-sensor integration (MSI) application involves extensive research and development time to understand and characterize the application domain; to determine and define the appropriate sensor suite; to analyze, characterize, and calibrate the individual sensor systems; to recognize and accommodate the various sensor interactions; and to develop and optimize robust merging code. Much of this process can benefit from adaptive learning, i.e., an output-based system can take raw sensor data and desired merged results as input and adaptively develop/determine an effective method if interpretation and merger. This approach significantly reduces the time required to apply MSI to a given application, while increasing the quality of the final result and provides a quantitative measure for comparing competing MSI techniques and sensor suites. The ability to automatically develop and optimize MSI techniques for new sensor suites and operating environments makes this approach well suited to the detection of mines and mine-like targets. Perhaps more than any other, this application domain is characterized by diverse, innovative, and dynamic sensor suites, whose nature and interactions are not yet well established. This paper presents such an outcome-based multi-image analysis system. An empirical evaluation of its performance and its application, sensor and domain robustness is presented.

The Integrated Radwaste Treatment System (IRTS) at the West Valley Demonstration Project (WVDP) is a pretreatment scheme to reduce the amount of salts in the high-level radioactive waste (vitrification) stream. Following removal of cesium-137 (Cs-137) by ion-exchange in the Supernatant Treatment System (STS), the radioactive waste liquid is volume-reduced by evaporation. Trace amounts of Cs-137 in the resulting distillate are removed by ion-exchange, then the distillate is discharged to the existing plant water treatment system. The concentrated product, 37 to 41 percent solids by weight, is encapsulated in cement producing a stable, low-level waste form. The Integrated Radwaste Treatment System (IRTS) operated in this mode from May 1988 through November 1990, decontaminating 450,000 gallons of high-level waste liquid; evaporating and encapsulating the resulting concentrates into 10,393 71-gallon square drums. A number of process changes and variations from the original operating plan were required to increase the system flow rate and minimize waste volumes. This report provides a summary of work performed to operate the IRTS, including system descriptions, process highlights, and lessons learned.

A data parallel version of the 3-D transport solver in DANTSYS has been in use on the SIMD CM-200`s at LANL since 1994. This version typically obtains grind times of 150--200 nanoseconds on a 2,048 PE CM-200. The authors have now implemented a new message passing parallel version of DANTSYS, referred to as DANTSYS/MPI, on the 512 PE Cray T3D at Los Alamos. By taking advantage of the SPMD architecture of the Cray T3D, as well as its low latency communications network, they have managed to achieve grind times of less than 10 nanoseconds on real problems. DANTSYS/MPI is fully accelerated using DSA on both the inner and outer iterations. This paper describes the implementation of DANTSYS/MPI on the Cray T3D, and presents two simple performance models for the transport sweep which accurately predict the grind time as a function of the number of PE`s and problem size, or scalability.

A major function of the Tank Waste Remediation System is to characterize wastes in support of waste management and disposal activities at the Hanford Site. Analytical data from sampling and analysis, along with other available information about a tank, are compiled and maintained in a tank characterization report (TCR). This report and its appendices serve as the TCR for single-shell tank 241-C-104. The objectives of this report are: (1) to use characterization data in response to technical issues associated with tank 241-C-104 waste; and (2) to provide a standard characterization of this waste in terms of a best-basis inventory estimate. The response to technical issues is summarized in Section 2.0, and the best-basis inventory estimate is presented in Section 3.0. Recommendations regarding safety status and additional sampling needs are provided in Section 4.0. Supporting data and information are contained in the appendices. This report supports the requirements of the Hanford Federal Facility Agreement and Consent Order (Ecology et al. 1996) milestone M-44-10.

Due to various upstream beam manipulations, the longitudinal bunch shape at the interactions point of the Stanford Linear Collider (SLC) is highly non-Gaussian. In this paper, we report beam-beam simulations with realistic longitudinal bunch shapes for the present SLC parameters and for the SLC-2000 luminosity upgrade. The simulation results allow us to estimate the luminosity enhancement due to the pinch effect and to find optimum parameter settings for the bunch compressor and the linac.

The authors report on measurements of the bunch energy spectrum at the end of the SLAC linac. Using the spectra obtained for two different linac rf phases they obtain both the bunch induced voltage and the longitudinal distribution of the bunch. The measurement results are compared with theoretical predictions. In particular, the induced voltage is in good agreement with that obtained using the calculated wake function for the SLAC linac. This measurement technique may be useful for monitoring changes of the linac bunch shape in the SLC.

In the Stanford Linear Collider (SLC) each beam, after leaving a damping ring, is compressed in the Ring-to-Linac (RTL) transfer line before entering the linear accelerator. At a bunch population of 4.0 {times} 10{sup 10} particles, due to the limited energy acceptance of the RL, approximately 15% of the beam has normally been lost. During the 1996 run, however, to eliminate this loss the bunch was partially precompressed in the damping ring, just before extraction; the beam loss in the RTL was reduced to almost zero. In Ref. 1 the operation and performance of precompression are presented. Also given is an analysis which, however, does not include the effects of the longitudinal wakefield on the beam dynamics. In this report the authors extend that analysis to include these effects.

In the Next Linear Collider (NLC) after being accelerated the beam is collimated to remove tail particles. Wakefields generated in the collimator section, however, can significantly degrade the beam emittance. The collimators are, therefore, carefully designed to balance and minimize the effects of the geometric and the resistive wall wakefields. Recent measurements of collimator wakefields in the Stanford Linear Collider (SLC) linac seem to confirm the geometric wakefield calculations but yield results for the resistive wall wakefield that are 3-4 times as large as expected. One possibility is that this discrepancy is due to the roughness of the collimator surface. In this report we estimate this effect.

A mathematical model has been developed which computes the concentration of tritiated water reemitted into the atmosphere by surface evaporation and plant transpiration using the Penman-Monteith equation. Using these rates, and assuming a deposition velocity for tritium, a coupled set of diffusion equations are then solved which yield the concentration of tritiated water as a function of time. The model is driven by a number of environmental parameters.

Since the 1960`s, beryllium machining was performed to make nuclear weapon components at the Department of Energy (DOE) Rocky Flats Plant. Beryllium exposure was assessed via fixed airhead (FAH) sampling in which the filter cassette was affixed to the machine, generally within a few feet of the worker`s breathing zone. Approximately 500,000 FAH samples were collected for beryllium over three decades. From 1984 to 1987, personal breathing zone (PBZ) samples were also collected as part of the evaluation of a new high velocity/low volume local exhaust ventilation (HV/LV LEV) system. The purpose of this study was to determine how the two types of sampling data could be used for an exposure assessment in the beryllium shop.

For intense beams, the analysis of tenuous halo components of the particle distribution that surround the main core of the distribution can be challenging. So-called core/test particle models in which a test particle is evolved in the applied and space-charge forces of the beam core have been instrumental in understanding the structure and extent of transverse beam halo produced by resonant particle interactions with the oscillating space-charge forces of a mismatched beam core. Here we present a core/test particle model developed for the analysis of longitudinal beam halo in intense, ion-beam rf linacs. Equations of motion are derived for a test particle moving interior to, and exterior to, a uniform density ellipsoidal beam bunch. Coupled transverse-longitudinal mismatch modes of the ellipsoidal beam envelope are analyzed. Typical parameters suggest the possibility of a low-order resonant interaction between longitudinal particle oscillations and a low-frequency envelope mode. Properties of this resonance are in an accompanying paper by the authors in these proceedings.

The characteristics of a piezoresistive accelerometer in shock environments are being studied at Sandia National Laboratories in the Mechanical Shock Testing Laboratory. A beryllium Hopkinson bar capability has been developed to extend the understanding of the piezoresistive accelerometer, in two mechanical configurations and with and without mechanical isolation, in the high frequency, high shock environments where measurements are being made. In this paper, recent measurements with beryllium single and split-Hopkinson bar configurations are described. The in axis performance of the piezoresistive accelerometer in mechanical isolation for frequencies of dc-30 kHz and shock magnitudes of up to 6,000 g as determined from measurements with a beryllium Hopkinson bar with a certified laser doppler vibrometer as the reference measurement are presented. Results of characterizations of the accelerometers subjected to cross axis shocks in a split beryllium Hopkinson bar configuration are also presented.

Thin films of LiCoO{sub 2} have been synthesized in which the strongest x-ray reflection is either weak or missing, indicating a high degree of preferred orientation. Thin-film solid state batteries with these textured cathode films can deliver practical capacities at high current densities. For example, for one of the cells 70% of the maximum capacity between 4.2 V and 3 V ({approximately}0.2 mAh/cm{sup 2}) was delivered at a current of 2 mA/cm{sup 2}. When cycled at rates of 0.1 mA/cm{sup 2}, the capacity loss was 0.001 %/cycle or less. The reliability and performance of Li-LiCoO{sub 2} thin-film batteries make them attractive for application in implantable devices such as neural stimulators, pacemakers, and defibrillators.

The first sinkhole at the Weeks Island Strategic Petroleum Reserve (SPR) site was initially observed in May 1992. Concurrent with the increasing dissolution of salt over the mined oil storage area below, it has gradually enlarged and deepened. Beginning in 1994 and continuing to the present, the injection of saturated brine directly into the sinkhole throat some 76 m beneath the ground surface essentially arrested further dissolution, providing time to make adequate preparation for the safe and orderly transfer of crude oil to other storage facilities. This mitigation measure marked the first time that such a control procedure has been used in salt mining; previously all control has been achieved by either in-mine or from-surface grouting. A second and much smaller sinkhole was noticed in early 1995 on an opposite edge of the SPR mine, but with a very similar geological and mine mechanics setting. Both sinkholes occur where the edges of upper 152 m and lower 213 m mined storage levels are nearly vertically aligned. Such coincidence maximizes the tensional stress development, leading to fracturing in the salt. This cracking takes 20 or more years to develop. The cracks then become flow paths for brine incursion, which after time …

Radioisotope Thermoelectric Generators (RTG) convert heat generated by radioactive decay into electricity through the use of thermocouples. The RTGs have a long operating life, are reasonably lightweight, and require little or no maintenance, which make them particularly attractive for use in spacecraft. However, because RTGs contain significant quantities of radioactive materials, normally plutonium-238 and its decay products, they must be transported in packages built in accordance with Title 10, Code of Federal Regulations, Part 71 (10 CFR 71). To meet these regulations, a RTG Transportation System (RTGTS) that fully complies with 10 CFR 71 has been developed, which protects RTGs from adverse environmental conditions during normal conditions of transport (e.g., shock, vibration, and heat). To ensure the protection of RTGs from shock and vibration loadings during transport, extensive over-the-road testing was conducted on the RTG`S to obtain real-time recordings of accelerations of the air-ride suspension system trailer floor, packaging, and support structure. This paper provides an overview of the RTG`S, a discussion of the shock and vibration testing, and a comparison of the test results to the specified shock response spectra and power spectral density acceleration criteria.

The paper presents an application of a constructive learning algorithm to optimization of circuits. For a given Boolean function f. a fresh constructive learning algorithm builds circuits belonging to the smallest F{sub n,m} class of functions (n inputs and having m groups of ones in their truth table). The constructive proofs, which show how arbitrary Boolean functions can be implemented by this algorithm, are shortly enumerated An interesting aspect is that the algorithm can be used for generating both classical Boolean circuits and threshold gate circuits (i.e. analogue inputs and digital outputs), or a mixture of them, thus taking advantage of mixed analogue/digital technologies. One illustrative example is detailed The size and the area of the different circuits are compared (special cost functions can be used to closer estimate the area and the delay of VLSI implementations). Conclusions and further directions of research are ending the paper.

This document summarizes the information on the historical uses, present status, and the sampling and analysis results of waste stored in Tank 241-AW-102. This report supports the requirements of the Tri-Party Agreement Milestone M-44-05.

Acceptance Test Report for the Sluicer Control System, Project W-320 This Acceptance Test Procedure (ATP) has been prepared to demonstrate that the C-Farm tank C-106 sluicer functions as required by the design criteria.

The Slice Emittance diagnostic is applicable to particle bunches in a linac that are of the order of a few degrees of phase long. In this technique, the transverse phase space of a longitudinal slice about one degree long is measured. The Slice Emittance diagnostic has been demonstrated on an electron bunch produced by a laser-photocathode RF gun. We measured the transverse beam matrix of one picosecond slices out of a 10 picosecond long bunch (about 10 degrees at the RF frequency of 2856 MHz). To implement this diagnostic one needs a phase shifter on part of the linac, a momentum analyzer (a dipole magnet followed by a slit) and a transverse emittance measuring system following the analyzer. By dephasing the last section (or sections) of the linac, longitudinal position in the bunch is correlated with energy. The momentum analyzer selects a short longitudinal slice by discriminating on energy and the transverse phase space of this slice is measured downstream of the analyzer. The Slice Emittance diagnostic, particularly in conjunction with tomographic analysis of the transverse phase space of the slices, provides significant new information about the 6-D phase space distribution of the beam. The experimental work done with this …

This document summarizes the information on the historical uses, present status, and the sampling and analysis results of waste stored in Tank 241-B-109. This tank has been listed on the Organic Salts Watch List. This-report supports the requirements of the Tri-Party Agreement Milestone M 44-10.