A project team at Lawrence Livermore National Laboratory has been developing inspection procedures and training materials for the NRC inspectors of safeguards systems at licensed nuclear facilities. This paper describes (1) procedures developed for inspecting for compliance with the Code of Federal Regulations, (2) training materials for safeguards inspectors on technical topics related to safeguards systems, such as computer surety, alarm systems, sampling techniques, and power supplies, and (3) an inspector-oriented methodology for evaluating the overall effectiveness of safeguards systems.

In the first of these two lectures the Higgs mechanism is reviewed in its most general form, which does not necessarily require the existence of Higgs bosons. The general consequences of the hypothesis that electroweak symmetry breaking is due to the Higgs mechanism are deduced just from gauge invariance and unitarity. In the second lecture the general properties are illustrated with three specific models: the Weinberg-Salam model, its minimal supersymmetric extension, and technicolor. The second lecture concludes with a discussion of the experiment signals for strong WW scattering, whose presence or absence will allow us to determine whether the symmetry breaking sector lies above or below 1 TeV. 57 refs.

An approximate method is described to evaluate the maximum acceptable residual magnetic field in the background of a neutral beam. 5 refs., 8 figs.

The poloidal field (PF) coil system on ITER, which provides both feedforward and feedback control of plasma position, shape, and current, is a critical element for achieving mission performance. Analysis of PF capabilities has focused on the 15 MA Q = 10 scenario with a 300-500 s flattop burn phase. The operating space available for the 15 MA ELMy H-mode plasma discharges in ITER and upgrades to the PF coils or associated systems to establish confidence that ITER mission objectives can be reached have been identified. Time dependent self-consistent free-boundary calculations were performed to examine the impact of plasma variability, discharge programming, and plasma disturbances. Based on these calculations a new reference scenario was developed based upon a large bore initial plasma, early divertor transition, low level heating in L-mode, and a late H-mode onset. Equilibrium analyses for this scenario indicate that the original PF coil limitations do not allow low li (<0.8) operation or lower flux states, and the flattop burn durations were predicted to be less than the desired 400 s. This finding motivates the expansion of the operating space, considering several upgrade options to the PF coils. Analysis was also carried out to examine the feedback current …

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We present results from ab-initio electronic-structure calculations of mechanical properties of the rhombohedral phase of vanadium reported in recent experiments (R Ia), and other predicted high-pressure phases (R Ib and bcc), focusing on properties relevant to dynamic experiments. We find that of the three transitions the largest volume collapse (1.3%) is for the R Ia to R Ib transition. Calculations of the single crystal and polycrystal elastic constants reveal a remarkably small discontinuity across the phase transitions even at zero temperature where the transitions are first order.

A group of documents from the U.S. Department of Health and Human Services announcing 60 new postdoctoral fellowships in AIDS research with the support of the National Institute of Allergy and Infectious Diseases.

A wide variety of physical phenomena arising within many scientific disciplines can be described by systems of coupled partial differential equations (PDEs). The numerical approximation of these PDEs often involves the solution of a system of algebraic equations (possibly nonlinear) which are typically large, sparse and nonsymmetric. The increasing computational demands required by the solution of such complex scientific applications has motivated the current direction toward large-scale parallel computers. We, therefore, consider solution techniques of representative systems of equations on large scale MIMD machines. Our primary emphasis in this study is the evaluation of iterative methods for the solution of nonsymmetric systems. In particular, we discuss two Krylov subspace methods, the conjugate gradient squared algorithm (CGS) and the generalized minimum residual method (GMRES), along with the multigrid algorithm (MG) on massively parallel MIMD architectures. The focus of this evaluation considers the performance of various algorithm and implementation variations over a broad selection of problems using a parallel machine.

Americium-241 is widely used as a radiation source, but it also has some potential risk if taken into the body. Although the radiotoxicity of americium-241 is small compared to other transuranic actinides, its effects on the reproductive system and on development of the placenta are more damaging than the effects of plutonium-239. A previous report based on a worst-case scenario involving a hypothetical fire accident in a contaminated facility indicated that there could have been a significant impact on nearby residents from a unit release of americium-241 via atmospheric dispersion. However, because the facility is located in a rural region where most drinking water supplies are drawn from private wells, it is believed that deposition of americium-241 from the atmosphere might also have impacts via the groundwater pathway by infiltration of rainwater. In this analysis, a three-dimensional analytical mathematical model is used to assess several aspects of americium-241 contamination of groundwater, including radioactive transformation, advection, dispersion, and soil sorption. Simulation results indicate that no significant radiological impacts would occur to the nearby residents via the groundwater pathway. 15 refs., 2 figs., 2 tabs.

Demountable vacuum seals for fusion reactor applications must be compatible with the reactor environment, easily scalable, very reliable and readily maintained by remote handling methods. We are investigating gate valves as well as flanges in our efforts to provide such seals. They are all metal and scalable without becoming massive and require no axial fasteners. Preliminary tests on an initial 30 cm aluminum flange using no soft metal coatings or gaskets have given several vacuum tight closures. Weld fatigue of this preliminary design caused degradation of the seal with further cycling to leakage levels of 10/sup -6/ Tl/sec, which is acceptable with differential pumping for either valves or flanges. Additional flange pairs using slightly altered geometry, fabrication techniques, and seal plating materials will be tested and reported on.

The TIBER II Tokamak Ignition/Burn Experimental Reactor design is the result of efforts by numerous people and institutions, including many fusion laboratories, universities, and industries. While subsystems will be covered extensively in other reports, this overview will attempt to place the work in perspective. Major features of the design are compact size, low cost, and steady-state operation. These are achieved through plasma shaping and innovative features such as radiation tolerant magnets and optimized shielding. While TIBER II can operate in a pulsed mode, steady-state is preferred for nuclear testing. Current drive is achieved by a combination of lower hybrid and neutral beams. In addition, 10 MW of ECR is added for disruption control and current drive profiling. The TIBER II design has been the US option in preparation for the International Thermonuclear Experimental Reactor (ITER). Other equivalent national designs are the NET in Europe, the FER in Japan and the OTR in the USSR. These designs will help set the basis for the new international design effort. 9 refs.

Amplification of a longitudinal perturbation of an ion pulse in a linear induction accelerator is calculated. The simplified accelerator model consists only of an applied field (E/sub a/), distributed gap impedance per meter (R) and beam-pipe capacity per meter (C). The beam is treated as a cold, one-dimensional fluid. It is found that normal mode frequencies are nearly real, with only a very small damping rate proportional to R. This result is valid for a general current profile and is not restricted to small R. However, the mode structure exhibits spatial amplification from pulse head to tail by the factor exp(RCLv/sub o//2), where L is pulse length and v/sub 0/ is drift velocity. This factor is very large for typical HIF parameters. An initially small disturbance, when expanded in terms of the normal modes, is found to oscillate with maximum amplitude proportional to the amplification factor.

This discussion concerns analyses of physical shock-tube and shock-boundary layer interaction experiments, supplemented by computations. The basic issue is that of evaluating the influence of reflected shock waves on enhancing the balance of turbulent kinetic energy and resultant turbulent materials mixing during implosion and shock reflection intervals. Increases in random velocity amplitudes of a factor of 5 or greater implying turbulent kinetic energy increases of a factor of 12 or more have been observed in some low Mach Number shock-tube and boundary-layer shock wave interaction experiments. These results are analyzed to estimate their influence on increased turbulent material mixing subsequent to shock interaction. The analyses are developed with the assistance of two-dimensional, pseudospectral free turbulent field shock interaction numerical simulations as well as compressible turbulent boundary-layer shock interaction calculations. Of particular interest is the influence of Mach Number and pre-existing turbulent intensity on the enhancement ratios. 24 refs., 8 figs.

Results of the synthesis of SYNROC C from both high surface area (16m/sup 2//g) and low surface area (4m/sup 2//g) powders at low and high oxygen fugacities indicate variations in radionuclide distribution. These results are most striking for the partitioning of uranium between perovskite and zirconolite. In highly active powders, the formation of a pyrochlore precursor ensures that equilibrium partitioning is approached. In less active powders, no low temperature pyrochlore is formed. As a result, the uranium partitioning is a function of nucleation processes. At high oxygen fugacities, uranium is rejected from perovskite and an additional uranium rich phase is formed precluding the synthesis of SYNROC C in air.

An open divertor configuration has been adopted for TIBER. Most recent designs, including DIII-D, NET and CIT use open configurations and rely on a dense edge plasma to shield the plasma from the gas produced at the neutralizer plate. Experiments on ASDEX, PDX, D-III, and recently on DIII-D have shown that a dense edge plasma can be produced by re-ionizing most of the gas produced at the plate. This high recycling mode allows a large flux of particles to carry the heat to the plate, so that the mean energy per particle can be low. Erosion of the plate can be greatly reduced if the average impact energy of the ions at the plate can be reduced to near or below the threshold for sputtering of the plate material. The present configuration allows part of the flux of edge plasma ions to be neutralized at the entrance to the pumping duct so that helium is pumped as well as hydrogen. 7 refs., 3 figs.

The main focus of the research efforts presently underway is the LWR power reactor surveillance program in which metallurgical test specimens of the reactor PV and dosimetry sensors are placed in three or more surveillance capsules at or near the reactor PV inner wall. They are then irradiated in a temperature and neutron flux-spectrum environment as similar as possible to the PV itself for periods of about 1.5 to 15 effective full-power years (EFPY), with removal of the last capsule at a fluence corresponding to the 30- to 40-year plant end-of-life (EOL) fluence. Because the neutron flux level at the surveillance position is greater than at the vessel, the test is accelerated wit respect to the vessel exposure, allowing early assessment of EOL conditions.

Parameters for operating points of TIBER-II, different from the baseline steady-state operation, are presented. These results have been generated with the MUMAK tokamak power balance code. Pulsed ignited and high performance steady-state operating points are described. 20 refs.

The baseline neutral beam energy for TIBER II was chosen to be 500 keV consistent with the use of near term dc acceleration technology. Adequate penetration to the axis for core current drive in larger ETR devices requires higher beam energies. However, beam instabilities may limit the current drive efficiency at high energy to lower values than predicted classically. The characteristics of TIBER II and a device with 4.5 m major radius as functions of beam energy are presented. 11 refs.

The design of air-insulated cables, which meet strict requirements, is described. Inductance, heat transfer, and electrostatic computer codes are used in design. Tests include electric circiut parameters, dc voltage holdoff, impulse voltage holdoff, heat rise at greater than peak duty, and shield mechanical strength.

The microwave superheater uses the synchrotron radiation from a thermonuclear plasma to heat gas seeded with an alkali metal to temperatures far above the temperature of material walls. It can improve the efficiency of the Compact Fusion Advanced Rankine (CFAR) cycle described elsewhere in these proceedings. For a proof-of-principle experiment using helium, calculations show that a gas superheat ..delta..T of 2000/sup 0/K is possible when the wall temperature is maintained at 1000/sup 0/K. The concept can be scaled to reactor grade systems. Because of the need for synchrotron radiation, the microwave superheater is best suited for use with plasmas burning an advanced fuel such as D-/sup 3/He. 5 refs.

Isomer ratio calculations were made for the reactions: /sup 175/Lu(n,..gamma..)/sup 176m,g/Lu, /sup 175/Lu(n,2n)/sup 174m,g/Lu, /sup 237/Np(n,2n)/sup 236m,g/Np, /sup 241/Am(n,..gamma..)/sup 242m,g/Am, and /sup 243/Am(n,..gamma..)/sup 244m,g/Am using modeled level structures in the deformed, odd-odd product nuclei. The hundreds of discrete levels and their gamma-ray branching ratios provided by the modeling are necessary to achieve agreement with experiment. Many rotational bands must be included in order to obtain a sufficiently representative selection of K quantum numbers. The levels of each band must be extended to appropriately high values of angular momentum.

The changes in the sensitivity (S) and the equivalent X-ray limit (P/sub x/) of several Bayard-Alpert gauges (BAGs) were studied when the size of the collectors was reduced from 125 ..mu.. to 50 ..mu.. and when different mounting envelopes were used. Based on this study, 400 custom BAGs with 50 ..mu.. collector were purchased from a vendor. The S and the P/sub x/ of these thin-collector BAGs were also measured.

The Fokker-Planck package FPPAC had been converted to the Connection Machine 2 (CM2). For fine mesh cases the CM2 outperforms the Cray-2 when it comes to time-integrating the difference equations. For long Legendre expansions the CM2 is also faster at computing the Fokker-Planck coefficients. 3 refs.

We have derived absolute dipole strength-function information for /sup 176/Lu from an average resonance capture study of /sup 175/Lu with 2-keV neutrons and from neutron capture cross-section measurements with neutrons from 30 keV to about 1 MeV. We found that we needed to increase our previous estimate of the relative M1/E1 strengths near 5 MeV by a factor of 3 and to revise downward the absolute magnitude of our E1 strength function. We accomplished the latter, while still maintaining continuity with the photonuclear data, by adjusting the one free parameter in our line shape. The present E1 and M1 strengths now seem correct both near the neutron separation energy and also around 1 MeV.