In order to anticipate problems from the radioactivation of neutral beam sources as a result of testing, a code has been developed which calculates both the radioactivities produced and the dose rates resulting therefrom. The code ACDOS2 requires neutron source strength and spectral distribution as input, or alternately, the source strength can be calculated internally from an input of neutral beam source parameters. A variety of simple geometries can be specified, and up to 12 times of interest following the shutdown of the neutron source. Radiation attenuating and daughter radioactivities are treated accurately. ACDOS2 is also of use for neutron-induced radioactivation problems involving accelerators, fusion reactors, or fission reactors.

The utilization of deuterium-based fuels offers the potential advantages of greater flexibility in blanket design, significantly reduced tritium inventory, potential reduction in radioactivity level, and utilization of an inexhaustible fuel supply. The conventional DT-fueled Reversed-Field Pinch Reactor (RFPR) designs are reviewed, and the recent extension of these devices to advanced-fuel (catalyzed-DD) operation is presented. Attractive and economically competitive DD/RFPR systems are identified having power densities and plasma parameters comparable to the DT systems. Converting an RFP reactor from DT to DD primarily requires increasing the magnetic field levels a factor of two, still requiring only modest magnet coil fields (less than or equal to 4 T). When compared to the mainline tokamak, the unique advantages of the RFP (e.g., high beta, low fields at the coils, high ohmic-heating power densities, unrestricted aspect ratio) are particularly apparent for the utilization of advanced fuels.

This report incorporates all lectures and presentations at the Advanced International Training Course on State Systems of Accounting for and Control of Nuclear Material held April 27 through May 12, 1981 at Santa Fe and Los Alamos, New Mexico, and Richland, Washington, USA. Authorized by the US Nuclear Non-Proliferation Act and sponsored by the US Department of Energy in cooperation with the International Atomic Energy Agency, the course was developed to provide practical training in the design, implementation, and operation of a state system of nuclear materials accountability and control that satisfies both national and international safeguards. Major emphasis for the 1981 course was placed on safeguards methods used at bulk-handling facilities, particularly low-enriched uranium conversion and fuel fabrication plants. The course was conducted by the University of California's Los Alamos National Laboratory, the Battelle Pacific Northwest Laboratory, and Exxon Nuclear Company, Inc. Tours and demonstrations were arranged at both the Los Alamos National Laboratory, Los Alamos, New Mexico, and the Exxon Nuclear fuel fabrication plant, Richland, Washington.

We discuss the design and fabrication of the all-metal vacuum chamber presently in use in the ZT-40 device. ZT-40 is the current experiment in the Los Alamos Reversed-Field Pinch (RFP) program. The new vessel, which replaces a ceramic one, is made of Inconel 625 and has major and minor diameters of 228 cm and 40 cm, respectively. It consists of 24 convoluted and straight sections welded into a single toroidal geometry. Presented are several design features showing diagnostic and vacuum port tubulations and thermal-electrical insulation isolating the unit from its conducting shell. We also discuss fabrication techniques and our procedure for cleaning and heat treatment designed to eliminate residual gas contamination in the Inconel material.

Some of the essential features of the experimental results and theoretical interpretations of ..cap alpha..-transfer reactions are summarized. (WHK)

We have been investigating methods for numerically extending the analytic solutions of field reversed theta pinch equilibria so that the results may be used in various stability and dynamics studies. We have used generalizations of elliptical Hill's vortex equilibria which accomodate separatrices with more rectangular shapes and which allow plasma to exist outside the separatrix. Although the equilibria are specified analytically inside the plasma surface, numerical techniques are required to generate the solution in the vacuum region. Two computer codes have been used in sequence. The first determines a set of external coils and their currents so that they match the known coil field inside the plasma. Then, given this coil field, we compute the contribution from the plasma currents to the fields in the vacuum region.

This paper discusses an alternative to weighing and sampling which is coming into increasing use in Oak Ridge Y-12 Plant for obtaining the uranium content of heterogeneous compounds and mixtures. This technique, nondestructive analyses (NDA), is based on measuring the natural or induced radioactivity of the uranium contained in the by-product materials. Nondestructive analyses equipment has been used in Y-12 for many years for performing certain qualitative measurements. For example, materials for discard are routinely checked by NDA to verify that their uranium contamination is negligible. Recently, however, three quantitative NDA systems have been put into operation in Y-12. These include systems for measurement of low- and high-density solids and a system for analysis of solution samples. Also, a study of the feasibility of measuring the uranium content of solution streams in the uranium recovery facility has been carried out. These items are briefly discussed.

A new ASTM Standard Recommended Guide on Application of ENDF/A Cross Section and Uncertainty File is in preparation by ASTM Committee E10 on Nuclear Technology and Applications. This ASTM Standard is being prepared in support of the standardization of physics-dosimetry procedures and data needed for Light Water Reactor (LWR) power plant pressure vessel and support structure materials surveillance and test reactor development programs. The main subject of this paper is the estabilishment of the ENDF/A Cross Section and Uncertainty File. The development of evaluated cross section files such as the evaluated nuclear data file, ENDF/B, has occurred mainly to meet the needs of physics calculators. These files are tested by calculations of well-measured benchmark problems such as reactivity or critical mass measurements. Data in the files have then been re-evaluated where disagreements with the benchmark measurements indicate data to be deficient.

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Interest in the use of an induction linac to accelerate heavy ions for the purpose of providing the energy required to initiate an inertially confined fusion reaction has stimulated a theoretical effort to investigate various beam dynamical effects associated with high intensity heavy ion beams. This paper presents a summary of the work that has been done so far; transverse, longitudinal and coupled longitudinal transverse effects are discussed.

In neutral-beam injection systems either all or part of the gas flow into the neutralizer comes from the plasma source. When the beam is switched on, ions from the plasma source, which used to contribute to the gas flow, are converted to an energetic beam and are pumped away: hence reducing the gas input to the neutralizer. The large volume of the neutralizer and its high conductance damp out rapid changes; for example, when the gas to the source is first turned on, there is a 230 msec exponential rise time associated with pressure in the neutralizer. The neutralizer in turn acts as a source of gas to the first chamber and the first chamber to the second and so on. Beam dumps become additional sources of gas in the second chamber and target tank as gas molecules are collisionally desorbed from the surface of the dump. A simple analytical model (the equivalent of an electrical RC circuit) of the volumes and conductances of the system has been used to describe the pressure variations. The use of time dependent sources terms in the model gives an estimate of the desorption rate from the dumps and its time variation during a …

We have used CAMAC hardware to provide communications between dissimilar computers for the ELMO Bumpy Torus (EBT) experiment. The software supports file and individual message transfers. The system has proven to be both reliable and fast, with transmission rates of about 36,000 baud.

A pump limiter system is described which is compatible with in-situ recoating of the limiter surface. The recoating could be done during normal tokamak operation. We have shown how this system is compatible with most of the constraints of fusion reactor operation and might provide a significant advantage over magnetic diverter and some other pump limiter geometries.

Using /sup 14/C-spiked pyrolytic graphite-coated quartz crucibles for the growth of nine ultra-pure germanium single crystals, we have determined the carbon content and distribution in these crystals. Using autoradiography, we observe a rapidly decreasing carbon cluster concentration in successively grown crystals. Nuclear radiation detectors made from the crystals measure the betas from the internally decaying /sup 14/C nuclei with close to 100% efficiency. An average value for the total carbon concentration (/sup 14/C + /sup 12/C) is approx. 2 x 10/sup 14/ cm/sup -3/, a value substantially larger than expected from earlier metallurgical studies. Contrary to the most recent measurement, we find the shape of the beta spectrum to agree very well with the statistical shape predicted for allowed transitions.

The March 1979 accident at General Public Utilities Nuclear Corporation (GPUNC) Three Mile Island Nuclear Power Station Unit 2 (TMI-2), resulted in the transfer of more than 1100 m/sup 3/ of contaminated water to the auxiliary and fuel handling building. The principal sources of the water were the makeup and letdown purification system and the containment building sump. The contaminated water was processed through an ion exchange system designated as EPICOR II. The EPICOR-II System is a three-stage process. The contaminated water passes through a first stage of ion exchange media, designated as prefilters, and then through the second and third stages, designated as demineralizers. The majority of the activity was deposited in the first-stage prefilters, which have a maximum administrative loading limit of 1300 curies. The predominant radionuclides present in the prefilters are cesium and strontium.

A new high-current thermionic gun has been installed on the CID injector at SLAC and brought into operation. The gun and pulser system generate three nanosecond pulses of about six amps peak which, when bunched in the subharmonic buncher system, produce in excess of 10/sup 11/ electrons in a single S-band accelerated bunch. Preliminary operation of the gun is described, and details of the avalanche cathode drive pulser are presented.

Chemical and biological experiments measured the solubility of 16 elements in coal fly ash and the short-term toxicity of coal fly ash to clams and phytoplankton. Of the elements studied, 10 to 60% of the As, Br, Cr, Sb, Se, Ni, Pb, and Sr dissolved within a 24-hour period. Elements which were less than 10% soluble in 24-hours included Cu, Zn, Na, La, Sc, Fe, Co and Eu. Littleneck clams (Protothaca staminea) were exposed to coal fly ash in flowing seawater for a 25-day period. At the end of the exposure Cu concentration in gills was 15 ..mu..g g/sup -1/ dry wt compared to 6 ..mu..g g/sup -1/ in control clams. Elements that were not elevated in the exposed clams were Mn, Fe, Ni, Zn, Se and As. The effects of the soluble fraction of coal fly ash on primary production was measured by /sup 14/C uptake rate on coastal phytoplankton. The addition of soluble coal fly ash material had no effect on the /sup 14/C uptake rate of phytoplankton. These measurements were made in the productive Washington shelf water during August. The literature indicates coal fly ash has a relatively low toxicity to plants and animals. Disposal methods could …

The review discusses the status of charged currents, neutral current reactions, Glashow-Iliopoulos-Maiani model, extension to 6 quarks, and CP violation. 115 references. (GHT)

Inverse cascades of magnetic quantities for turbulent incompressible magnetohydrodynamics are reviewed, for two and three dimensions. The theory is extended to the Strauss equations, a description intermediate between two and three dimensions appropriate to tokamak magnetofluids. Consideration of the absolute equilibrium Gibbs ensemble for the system leads to a prediction of an inverse cascade of magnetic helicity, which may manifest itself as a major disruption. An agenda for computational investigation of this conjecture is proposed.

The design concept and performance characteristics of the first-wall design for the phase-1 INTOR (International Tokamak Reactor) study is described. The reference design consists of a water-cooled stainless steel panel. The major uncertainty regarding the performance of the bare stainless steel wall relates to the response of a thin-melt layer predicted to form on limited regions during a plasma disruption. A more-complex backup design, which incorporates radiatively cooled graphite tiles on the inboard wall, is briefly described.

A preliminary conceptual study has been made of the Modular Stellarator Reactor (MSR) as a steady-state, ignited, DT-fueled, magnetic fusion reactor. The MSR concept combines the physics of classic stellarator confinment with an innovative, modular-coil design. Parametric tradeoff calculations are described, leading to the selection of an interim design point for a 4.8-GWt plant based on Alcator transport scaling and an average beta value of 0.04 in an l = 2 system with a plasma aspect ratio of 11.

Limited-angle emission tomography was investigated using a two-dimensional phantom to generate positron events simulating a camera with two opposed parallel position-sensitive detectors collecting data within a 90/sup 0/ cone. The data, backprojected onto lines passing through the phantom volume, is used with a matrix reconstruction method to provide two-dimensional images. Image quality was measured using the standard deviation of the reconstructions with respect to the original phantom. The application of Phillips-Twomey smoothing to the deconvolution matrices has substantially improved the original reconstructions, a factor of 1.9 in signal to noise ratio, giving S/N = 3.4 for a phantom having an average of 150 events/pixel. Using photon time-of-flight to restrict the reconstruction volume a further considerable improvement is made. When the time-of-flight limited the contributing volume to 4 lines out of 11 the improvement was another factor of 1.9 giving S/N = 6.0 for the same phantom. Comparable increases in signal to noise ratios are expected for three-dimensional reconstructions.

Preliminary tests of a method for regulating the accelerator perveance of a high-power neutral beam, by controlling the plasma source have been conducted and are encouraging. The phase shifts and feedback paths were identified and quantified, and stabilization was achieved by adding an R-C snubber at the accelerator power supply output which reduced the destabilizing phase lags. The incorporation of such regulators into future systems is envisioned to make these high-power neutral beam systems cheaper and easier to operate.

The paramagnetic scattering was recently measured for EuO. It was found that spin-wave-like excitations develop for wave vectors approaching the zone boundary. The spectrum was found to be well described by damped harmonic oscillators (also called the two-pole-approximation). This approximation was used previously in the correlation theory primarily to calculate static properties. Selfconsistent dynamic and static calculations have been performed for EuO, which is an ideal Heisenberg magnet with significant second nearest neighbor interaction (J/sub 2/ = J/sub 1/5). The two-pole approximation describes accurately the correlation range, the static susceptibility and the qualitative behavior of the dynamic properties (i.e., the wave vector at which peaks appear in the spectrum as a function of temperature). However, in order to also obtain the correct frequency scale it is necessary to use a cut-off of the spectrum at high frequencies, which cannot be seen experimentally, but which significantly influences the frequency moments. It was found that the finite J/sub 2/ has significant importance for a comparison between theory and experiment. It is concluded that the calculation for a simple cubic n.n. magnet by Hubbard does not describe the EuO data accurately, neither with respect to lineshape nor frequency scale. Significant differences are to …