During the past few years, the use of computers in radiation safety systems has become more widespread. This is not surprising given the ubiquitous nature of computers in the modern technological world. But is a computer a good choice for the central logic element of a personnel safety system. Recent accidents at computer controlled medical accelerators would indicate that extreme care must be exercised if malfunctions are to be avoided. The Department of Energy has recently established a sub-committee to formulate recommendations on the use of computers in safety systems for accelerators. This paper will review the status of the committee's recommendations, and describe radiation protection interlock systems as applied to both accelerators and to irradiation facilities. Comparisons are made between the conventional relay approach and designs using computers. 6 refs., 6 figs.

After a brief enumeration of the advantages of electron-positron collisions to study elementary particle physics, the present and future of electron-positron facilities are briefly reviewed, and the perspectives for future physics with electron-positron collisions are discussed. 20 refs., 10 figs. (LEW)

A model for the W(001) surface reconstruction phase transition is studied to elucidate the dependence of transition temperature on interaction range and other model parameters. For the parameter set chosen extending the range of the interaction without changing the total reconstruction energy increases the model transition temperature somewhat. This reduces a previously reported discrepancy between the experimental transition temperature and that consistent with the calculated reconstruction energy, but only marginally. 12 refs., 1 fig., 1 tab.

Electron capture and loss by fast highly charged ions in a gas target, and ionization of the target by passage of the fast projectile beam, are fundamental processes in atomic physics. These processes, along with excitation, can be experimentally studied separately (''singles'') or together (''coincidence''). This paper is a review of recent results on singles measurements for electron capture and loss and for target ionization, for velocities which are generally high relative to the active electron, including recent ionization measurements for a nearly relativistic projectile. 11 refs., 6 figs.

We report as inelastic neutron scattering study of the uniaxial dilute antiferromagnets Fe/sub 1-x/Mg/sub x/Cl/sub 2/, for x = 0.3, 0.45 and 0.6. The first two samples have long-range AF order. Their spin-wave peaks are broadened by the exchange fluctuations. The x = 0.6 sample oders like an Ising spin-glass with a very short AF correlation length (xi approx. = 10 A). For wavelength lambda less than or equal to xi, the spin-wave peaks are similar to the dilute antiferromagnets, but for lambda less than or equal to 2xi, the peak shapens up and becomes resolution limited at the zone center. We give a simple explanation of this behavior. 13 refs., 1 fig.

We present a solid state accelerator concept utilizing particle acceleration along crystal channels by longitudinal electron plasma waves in a metal. Acceleration gradients of order 100 GV/cm are theoretically possible, but channeling radiation limits the maximum attainable energy to 10/sup 5/ TeV for protons. Beam dechanneling due to multiple scattering is substantially reduced by the high acceleration gradient. Plasma wave dissipation and generation in metals are also discussed.

Some examples of nuclear data in which the uncertainty has been underestimated, or at least appears to be underestimated, are reviewed. The subjective aspect of the problem of systematic uncertainties is discussed. Historical aspects of the data uncertainty problem are noted. 64 refs., 6 tabs.

Nuclear material entrained wastes are generated at the Plutonium Facility at Los Alamos National Laboratory. These wastes are removed from the glove box lines using the bagout method. This is a manual operation performed by technicians. An automated system is being developed to relieve the technicians from this task. The system will reduce the amount of accumulated radiation exposure to the worker. The primary components of the system consist of a six degree of freedom robot, a bag sealing device, and a small gantry robot. 1 ref., 5 figs.

A new method was presented for LMFBR intermediate heat exchanger (IHX) analysis in real time for purposes of continuous on-line data validation, plant state verification and fault identification. For the validation of this methodology the EBR-II IHX transient during Test 8A was analyzed. This paper presents the results of this analysis.

It has long been known that carbon steel exposed to some geothermal brines is aggressively attacked, and large corrosion allowances must be made in the design of piping used in such environments. In addition, scaling of the pipes reduces the flow through within a short period of time. Several high temperature polymer concretes have been developed which can be used as non-corrosive liner materials. In addition, polymer concretes with high thermal conductivities have been developed which may be used as heat exchanger tubes for geothermal brines. Studies have indicated that polymer concretes will not scale as rapidly as carbon steel does, thus making them attractive alternatives for heat exchanger tubes. Thin walled, thermally conductive polymer concrete tubes have been made that can withstand pressures >4.1 MPa at 150/sup 0/C without leaking. Continuing studies are being made to characterize these materials and evaluate them for heat exchanger applications.

Some examples are given of where current research in seismic and electromagnetic imaging may eventually lead to practical technologies for exploration. These are technologies that will provide a relatively high resolution, 2-D and 3-D parameterized picture of the earth to depths of two to three km. Parameters discussed include P- and S-wave velocities and electrical resistivity.

This paper covers selected aspects of the acute and long term health effects excluding acute radiation syndrome and carcinogenesis, resulting from exposure to ionizing radiation. The changes addressed in this paper are those witnessed within an organ or whole body rather than at the molecular or even cellular level. They include acute and late health effects. Some of these effects are threshold effects, meaning that the dose must exceed a certain threshold before one sees these effects. Less than the threshold dose results in no observable organ or whole body effect. The severity of the effects correlate directly with the amount of cell damage or cell death that has occurred. 15 refs., 4 figs., 8 tabs.

While fixed-target experiments in storage rings were suggested more than twenty-five years ago, little work has been done and virtually none in this country although interest seems to be growing. We survey the advantages, limitations and possibilities. Luminosities of L approx. = 10/sup 33/cm/sup -2/s/sup -1/ for electrons up to 15 GeV should be achievable now with the PEP storage ring at SLAC with good beam lifetime and emittance for target thicknesses n/sub t/ approx. 10/sup 15//cm/sup 2/. This is thin but ideal for optically pumped, polarized gas targets. Providing longitudinally polarized beams at such targets would provide a unique facility for high luminosity polarized e/sub +-/ + polarized ..gamma.., polarized e/sub +-/ + polarized A and polarized ..gamma.. + polarized A experiments. Other possibilities include the production of both external and internal beams for basic and applied science. Multiple bypass insertions are considered for thicker targets as well as production and storage of exotic, short-lived beams or for production of photon beams with undulators. The related question of multi-turn injection and extraction is also considered in such a context. Several systematic machine physics studies are suggested, e.g., ion-induced, multi-bunch instabilities with e/sub +-/ beams. The SLAC storage ring PEP …

The ultralow background Ge spectrometer developed by the USC/PNL group is used as a detector of cold dark matter candidates from the halo of our galaxy and of solar axions (and other light bosons), yielding interesting bounds. Some of them are: heavy standard Dirac neutrinos with mass 20 GeV less than or equal to m less than or equal to 1 TeV are excluded as main components of the halo of our galaxy; Dine-Fischler-Srednicki axion models with F/2x/sub e/' less than or equal to 0.5 x 10/sup 7/ GeV are excluded. 22 refs., 7 figs.

Storage rings with internal targets are described, using PEP as an example. The difference between electrons and heavier particles such as protons, antiprotons, and heavy ions is also discussed because it raises possibilities of bypass insertions for more exotic experiments. PEP is compared to other rings in various contexts to verify the assertion that it is an ideal ring for many fundamental and practical applications that can be carried on simultaneously. (LEW)

The effect of fabrication variables on the irradiation behavior of uranium silicide-aluminum dispersion fuel plates is examined. The presence of minor amounts of metallic uranium-silicon was found to have no detrimental effect, so that extensive annealing to remove this phase appears unnecessary. Uniform fuel dispersant loading, low temperature during plate rolling, and cold-worked metallurgical condition of the fuel plates all result in a higher burnup threshold for breakaway swelling in highly-loaded U/sub 3/Si fueled plates.

At the Second Regional Workshop, held at Argonne National Laboratory 23 to 24 June 1986, fifteen participants from four countries heard ten presentations on Problems 1, 2, and 6. This note includes information about the workshop and summaries of the results for Problems 1 and 2.

One important use of fusion product diagnostics is in the determination of the deuterium ion temperature from the magnitude of the 2.5 MeV d(d,n)/sup 3/He neutron emission. The detectors, calibration methods, and limitations of this technique are reviewed here with emphasis on procedures used at PPPL. In most tokamaks, the ion temperature deduced from neutrons is in reasonable agreement with the ion temperature deduced by other techniques.

Atomic data for the electron-impact ionization of ions in the Fe isonuclear sequence is reviewed. The best available data are identified. Comments are made on current research activities leading to future data for Fe ions. 23 refs., 29 figs., 12 tabs.

The growth of epitaxial films of cerium (Ce)/vanadium (V)/on single crystal sapphires (..cap alpha..-Al/sub 2/O/sub 3/) was studied by in-situ reflection high energy electron diffraction and x-ray scattering. For the first time Ce(111) single crystal films was grown on V(110)/Al/sub 2/O/sub 3/(1120) in the Frank-van der Merwe mode. A new epitaxial orientation, different from the well known Nishiyama-Wasserman or Kurdjumov-Sachs orientations is found in the present study. Subsequent V(110) layers grow epitaxially with three equivalent domains.

Coincidence measurements of charge transfer and simultaneous projectile electron excitation provide insight into correlated two-electron processes in energetic ion-atom collisions. Projectile excitation and electron capture can occur simultaneously in a collision of a highly charged ion with a target atom; this process is called resonant transfer and excitation (RTE). The intermediate excited state which is thus formed can subsequently decay by photon emission or by Auger-electron emission. Results are shown for RTE in both the K shell of Ca ions and the L shell of Nb ions, for simultaneous projectile electron loss and excitation, and for the effect of RTE on electron capture.

The goal of this workshop was to probe in depth a few of the areas of possible physics made possible by the availability of an intermediate energy heavy-ion physics facility. There was a special emphasis on physics that would be possible only with a storage/cooler ring. Topics discussed were nuclei far from stability, quantum electrodynamics, giant resonances and photonuclear reactions, and high energy gamma-ray production. Individual papers in this meeting were abstracted separately.

A range of issues pertaining to heavy flavors at the SSC is examined including heavy flavor production by gluon-gluon fusion and by shower evolution of gluon jets, flavor tagging, reconstruction of Higgs and W bosons, and the study of rare decays and CP violation in the B meson system. A specific detector for doing heavy flavor physics and tuned to this latter study at the SSC, the TASTER, is described. 36 refs., 10 figs.

Within the next few months the FASTBUS Software Working group hopes to distribute the Specification for Standard Routines for FASTBUS. The draft specification will go to the members of the overseeing NIM committee for review. This paper presents the current status of the specification. It includes a list of the goals of the specification; some details of the concepts embedded in it; as well as an overview of the software implementations of the previously distributed draft versions of the specification.