A surface ionization-diffusion-type ionization source that uses a rhenium filament overplated with platinum has been developed and optimized for 0.1-ng neptunium samples. This source is capable of measuring the neptunium content of nuclear-test-debris samples to 0.15% precision at the 95% confidence level. 14 refs., 3 figs., 3 tabs.

Simultaneous erosion and redeposition of copper and 304 stainless steel under controlled and continuous plasma (D,He,Ar) bombardment has been investigated in the PISCES-facility, which generates typical edge-plasma conditions of magnetic fusion devices. The plasma bombardment conditions are: incident ion flux in the range from 10/sup 17/ to 10/sup 18/ ions/sec/cm/sup 2/, ion bombarding energy of 100 eV, electron temperature in the range from 5 to 15 eV, plasma density in the range from 10/sup 11/ to 10/sup 13/ cm/sup -3/, target temperature in the range from 300 to 900K, and the total ion fluence in the range from 10/sup 20/ to 10/sup 22/ ions/cm/sup 2/. The net erosion yield under redeposition is found to be significantly smaller than the classical sputtering yield data. A first-order modeling is attempted to interpret the erosion and redeposition behavior of materials under plasma bombardment. It is pointed out both theoretically and experimentally that the mean free path for electron impact ionization of the sputtered material is the key parameter to control the overall mechanism of erosion and redeposition. Strongly modified surface morphologies of bombarded targets are observed and indicate a retrapping effect.

Features of the beamstrahlung flux from the SLC interaction point are discussed, and intensity estimates given. A Cherenkov detector intended to monitor the flux is described.

The goals of the SLAC Linear Collider, SLC, are to develop the techniques of linear colliders and to do physics at and slightly above the energy necessary to produce the Z/sup 0/. A short review is given of the physics goals of the SLC, followed by the status of the SLC and its detectors. Plans for accelerating polarized electrons at SLC are also discussed. 6 figs. (LEW)

A new finite element mesh file format which provides a neutral interface from a mesh generation program to a finite element analysis program is described. The file format has been constructed to allow for multiple element types and flexible definition of boundary conditions. It provides for arbitrary element connectivity and attributes, so that continuum and structural elements can easily be accommodated in the same model. Element side boundary conditions as well as nodal point boundary conditions are supported. The file format is applicable to finite element models in any n-dimensional space. Both bandwidth and wavefront optimization schemes can be accommodated with the GENESIS file format. 1 ref.

The HIFAR program addresses the generation of high-power, high-brightness beams of heavy ions, the understanding of the scaling laws in this novel physics regime, and the validation of new accelerator strategies, to cut costs. Key elements to be addressed include: (1) beam quality limits set by transverse and longitudinal beam physics; (2) development of induction accelerating modules, and multiple beam hardware, at affordable costs; (3) acceleration of multiple beams with current amplification - both new features in a linac - without significant dilution of the optical quality of the beams; (4) fianl bunching, transport, and accurate focussing on a small target.

Ion temperature profiles with a time resolution of 2 to 5 ms have been measured on PBX by charge-exchange-recombination spectroscopy (CXRS) and a neutral-particle charge-exchange analyzer (NPA). The sightlines of both diagnostics crossed the trajectory of a near-perpendicular heating beam, which enhanced the local neutral density (proportional to signal strength) and provided spatial resolution. The time resolution of these two independent techniques is sufficient to see sawtooth oscillations and other MHD activity. Effects of these phenomena on the toroidal rotation velocity profile, v/sub phi/(r), are clearly observed by CXRS. For example, a sharp drop in the central v/sub phi/ occurs at the sawtooth crash, followed by a linear rise during the quiescent phase. The NPA results are compared with those from CXRS.

In February 1983, the US Department of Energy (DOE) identified a location in Deaf Smith County, Texas, as one of the nine potentially acceptable sites for mined geologic repository for spent nuclear fuel and high-level radioactive waste. To determine their suitability, the Deaf Smith County site and eight other potentially acceptable sites have been evaluated in accordance with the DOE's General Guidelines for the Recommendation of Sites for the Nuclear Waste Repositories. The Deaf Smith County site is in the Permian Basin, which is one of five distinct geohydrologic settings considered for the first repository. On the basis of the evaluations reported in this EA, the DOE has found that the Deaf Smith County site is not disqualified under the guidelines.

It is shown that new observations of large scale structure in the universe (voids, foam, and large-scale velocity fields) are best understood if the dominant matter of the universe is in the form of massive (9eV less than or equal to m/sub nu/ less than or equal to 35 eV) neutrinos. Cold dark matter, even with biasing, seems unable to duplicate the combination of these observations (although a fine-tuned loophole with cold matter and percolated explosions may also marginally work.) The previous fatal problems of galaxy formation with neutrinos can be remedied by combining them with either cosmic strings or explosive galaxy formation. The former naturally gives the scale-free correlation function for galaxies, clusters, and superclusters, and gives large, but not necessarily spherical voids. The latter naturally gives spherical voids, but requires fine tuning and percolation to get the large scales and the scale-free correlation function. 39 refs.

Management aspects of data communications facilities at Fermilab are described. Local area networks include Ferminet, a broadband CATV system which serves as a backbone-type carrier for high-speed data traffic between major network nodes; micom network, four Micom Micro-600/2A port selectors via private twisted pair cables, dedicated telephone circuits, or Micom 800/2 statistical multiplexors; and Decnet/Ethernet, several small local area networks which provide host-to-host communications for about 35 VAX computers systems. Wide area (off site) computer networking includes an off site Micom network which provides access to all of Fermilab's computer systems for 10 universities via leased lines or modem; Tymnet, used by many European and Japanese collaborations: Physnet, used for shared data processing task communications by large collaborations of universities; Bitnet, used for file transfer, electronic mail, and communications with CERN; and Mfenet, for access to supercomputers. Plans to participate in Hepnet are also addressed. 3 figs. (DWL)

In February 1983, the US Department of Energy (DOE) identified a location in Deaf Smith County, Texas, as one of nine potentially acceptable sites for mined geologic repository for spent nuclear fuel and high-level radioactive waste. To determine their suitability, the Deaf Smith County site and eight other potentially acceptable sites have been evaluated in accordance with the DOE's General Guidelines for the Recommendation of Sites for the Nuclear Waste Repositories. The Deaf Smith County site is in the Permian Basin, which is one of five distinct geohydrologic settings considered for the first repository. On the basis of the evaluations reported in this EA, the DOE has found that the Deaf Smith County site is not disqualified under the guidelines. On the basis of these findings, the DOE is nominating the Deaf Smith County site as one of five sites suitable for characterization. 3 figs.

A view of the software structure typical of a High Energy Physics experiment is given and the availability of general software modules in most of the important regions is discussed. The aim is to provide a framework for discussion of capabilities and inadequecies and thereby define areas where effort should be assigned and perhaps also to serve as a useful source document for the newcomer to High Energy Physics. 74 refs.

It is found that energy dependent diffusion theory provides excellent accuracy in the modelling of transport of neutral atoms in fusion plasmas. Two reasons in particular explain the good accuracy. First, while the plasma is optically thick for low energy neutrals, it is optically thin for high energy neutrals and diffusion theory with Marshak boundary conditions gives accurate results for an optically thin medium even for small values of 'c', the ratio of the scattering to the total cross section. Second, the effective value of 'c' at low energy becomes very close to one due to the down-scattering via collisions of high energy neutrals. The first reason is proven both computationally and theoretically by solving the transport equation in a power series in 'c' and the diffusion equation with 'general' Marshak boundary conditions. The second reason is established numerically by comparing the results from a one-dimensional, general geometry, multigroup diffusion theory code, written for this purpose, with the results obtained using the transport code ANISN.

The MARK III Collaboration has collected a data sample of 5.8 x 10/sup 6/ produced J/psi's. Results from the previous measurements in radiative decays are updated and compared with the hadronic decays. In particular, data which are relevant to understand the nature of the theta(1720), iota(1440) and/or E(1420), are presented. A preliminary analysis of a systematic study of direct J/psi decays into the vector(J/sup PC/=/sup - -/) and the tensor (J/sup PC/=2/sup + +/) mesons are presented. Some vector-scalar decays are discussed. Among the baryonic modes, observation of several SU(3) violating decays is reported. 23 refs., 10 figs.

The double-cone-shaped Cascade reaction chamber rotates at 50 rpm to keep a blanket of ceramic granules in place against the wall as they slide from the poles to the exit slots at the equator. The 1 m-thick blanket consists of layers of carbon, beryllium oxide, and lithium aluminate granules about 1 mm in diameter. The x rays and debris are stopped in the carbon granules; the neutrons are multiplied and moderated in the BeO and breed tritium in the LiAlO/sub 2/. The chamber wall is made up of SiO tiles held in compression by a network of composite SiC/Al tendons. Cascade operates at a 5 Hz pulse rate with 300 MJ in each pulse. The temperature in the blanket reaches 1600 K on the inner surface and 1350 K at the outer edge. The granules are automatically thrown into three separate vacuum heat exchangers where they give up their energy to high pressure helium. The helium is used in a Brayton cycle to obtain a thermal-to-electric conversion efficiency of 55%. Studies have been done on neutron activation, debris recovery, vaporization and recondensation of blanket material, tritium control and recovery, fire safety, and cost. These studies indicate that Cascade appears to …

This report is compiled by the Nuclear Waste Treatment Program and the Hanford Waste Vitrification Program at Pacific Northwest Laboratory to document progress on liquid-fed ceramic melter (LFCM) vitrification technology. Progress in the following technical subject areas during the fourth quarter of FY 1985 is discussed: melting process chemistry and glass development, feed preparation and transfer systems, melter systems, canister filling and handling systems, off-gas systems, process/product modeling and control, and supporting studies.

Magnetic helicity is approximately conserved by the turbulence associated with resistive instabilities of plasmas. To generalize the application of the concept of helicity, the helicity content of an arbitrary bounded region of space will be defined. The definition has the virtues that both the helicity content and its time derivative have simple expressions in terms of the poloidal and toroidal magnetic fluxes, the average toroidal loop voltage and the electric potential on the bounding surface, and the volume integral of E-B. The application of the helicity concept to tokamak plasmas is illustrated by a discussion of so-called MHD current drive, an example of a stable tokamak q profile with q less than one in the center, and a discussion of the possibility of a natural steady-state tokamak due to the bootstrap current coupling to tearing instabilities.

A device is designed to detect bremsstrahlung at wide angles and wavelengths near the visible. A schematic diagram of the monitor is shown. An analysis of the performance of the monitor is given in terms of photomultiplier output and luminosity. 3 refs., 1 fig. (DWL)

By using a photocathode instead of a thermionic cathode in a klystron, the possibility exists to make very short low energy spread bunches of high efficiency. However, there is a fundamental limit to the efficiency of a conventional output cavity, such as the one used in the SLAC XK-5 klystron. The fringing electric field in the drift tube acts on the beam as it leaves the output cavity and results in a net acceleration. All electrons which eventually reach the collector emerge from the drift tube with a substantial kinetic energy and as a result, the highest practical efficiency is about 80% for a 400 kV single output cavity tube. The behavior of these very short low energy spread bunches was calculated using MASK, a 2D field and particle program as well a much simpler 1D program. Using multiple output cavities, it may be possible to extract energy from the electrons more efficiently.

A method is developed to compress a heavy-ion beam longitudinally in such a way that the compressed pulse has a constant line-charge density profile and uniform longitudinal momentum. These conditions may be important from the standpoint of final focusing. By realizing the similarity of the equations that describe the 1-D charged-particle motion to the equations that describe 1-D ideal gas flow, the evolution of lambda and the velocity tilt can be calculated using the method of characteristics developed for unsteady supersonic gasdynamics. Particle simulations confirm the theory. Various schemes for pulse shaping have been investigated.

Two improvements to the SPRED multichannel VUV spectrographs used on the TFTR and PBX tokamaks have been made: (1) A new 2100-g/mm grating covering the 100 to 320 A region with 0.4 A resolution (FWHM) has been added to the existing 450 g/mm grating (100 to 1100 A with 2 A resolution), and (2) the TFTR SPRED has been absolutely calibrated using synchrotron radiation from the NBS SURF II facility, while the PBX system has been calibrated using conventional branching ratios along with line ratios from charge-exchange-recombination-excited lines. The availability of high resolution spectra in the 100 to 320 A range provides improved measurements of metallic ion emissions and, when the instrument views across a neutral beam as in PBX, allows carbon and oxygen densities to be measured via charge exchange recombination spectroscopy.

Calculation of the electrostatic scalar potential in ellipsoidal coordinates is outlined. The ellipsoidal coordinate system is described, and the Laplace equation is discussed for this system. Special charge distributions having ellipsoidal symmetry, and therefore most easily treated in ellipsoidal coordinates, are assumed and their scalar potentials calculated, including the ellipsoidal shell, two-dimensional and three-dimensional Gaussian charge distribution, and two-dimensional uniform distribution. 2 refs. (LEW)

In the thirty-odd years that core-disruptive accidents have been analyzed, great advances have been made both in understanding the physical phenomena involved and in development of computational techniques to deal with them. More realistic modeling has tended to reduce predicted accident consequences. Some safety issues have been satisfactorily resolved, but some new ones have arisen. The unprotected loss-of-flow accident continues to be a source of potentially significant energetics should core disruption occur. 27 refs.

We have conducted parametric economic studies for heavy-ion-fusion electric power plants. We examined the effects on the cost of electricity of several design parameters: cost and cost scaling for the reactor, driver, and target factory; maximum achievable chamber pulse rate; target gain; electric conversion efficiency; and net electric power. Using the most recent estimates for the heavy-ion-driver cost along with the Cascade reactor cost and efficiency, we found that a 1.5 to 3 GWe heavy-ion-fusion power plant, with a pulse rate of 5 to 10 Hz, can be competitive with nuclear and coal power plants.