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A 0. 4 mm Interferometer System Using Dielectric Waveguide (open access)

A 0. 4 mm Interferometer System Using Dielectric Waveguide

A 0.4 mm submillimeter-wave, phase-modulated polarimeter/interferometer is used for simultaneous time-dependent measurement of line-averaged electron density and poloidal field-induced Faraday rotation along chords of the plasma column in ISX-B tokamak. Heterodyna detection and hollow dielectric waveguide are utilized to achieve the high sensitivity required for the multichord equipment.
Date: January 1, 1982
Creator: Hutchinson, D. P.; Ma, C. H.; Staats, P. A. & Vander Sluis, K. L.
System: The UNT Digital Library
0/sup -/ to 0/sup +/ beta decay in A = 16 (open access)

0/sup -/ to 0/sup +/ beta decay in A = 16

Techniques and results of the measurement of the beta-decay rate of the first excited state of /sup 16/N to the ground state of /sup 16/O are reported. Energy levels involved in the decay are shown, and the /sup 16/N 0/sup -/ beta decay branching ration is given. (WHK)
Date: January 1, 1982
Creator: Gagliardi, C.; Garvey, G. T.; Wrobel, J. R. & Freedman, S. J.
System: The UNT Digital Library
1-D hybrid code for FRM start-up (open access)

1-D hybrid code for FRM start-up

A one-D hybrid has been developed to study the start-up of the FRM via neutral-beam injection. The code uses a multi-group numerical model originally developed by J. Willenberg to describe fusion product dynamics in a solenoidal plasma. Earlier we described such a model for use in determining self-consistent ion currents and magnetic fields in FRM start-up. However, consideration of electron dynamics during start-up indicate that the electron current will oppose the injected ion current and may even foil the attempt to achieve reversal. For this reason, we have combined the multi-group ion (model) with a fluid treatment for electron dynamics to form the hybrid code FROST (Field Reversed One-dimensional STart-up). The details of this merger, along with sample results of operation of FROST, are given.
Date: January 1, 1982
Creator: Stark, R. A. & Miley, G. H.
System: The UNT Digital Library
2. 6/sup 0/K refrigeration system for CBA magnet testing (open access)

2. 6/sup 0/K refrigeration system for CBA magnet testing

The superconducting magnets for the accelerator's rings will be cooled by a forced flow supercritical helium system from a central refrigeration plant. The design temperature for these magnets varies from 2.6 to 3.8/sup 0/K depending on a magnet's location in the ring. This paper describes the forced flow cooling system for testing a prototype magnet near 2.6/sup 0/K; this lowest temperature being of special interest to evaluate magnet quench protection. The test forced flow cooling system uses a three-stage approach, including an ejector pumped bath, similar to a cycle described previously. The coolant exists at 3.8/sup 0/K from these first stages and is then cooled further in a 64 cm diameter by 3 m high shielded liquid helium dewar. The supercritical helium gas passes through a submerged copper coil in this bath which is pumped to a pressure of 65 mm absolute by a screw compressor system. Temperatures are measured by thermistors located in the gas stream, and also embedded in the magnet coil.
Date: January 1, 1982
Creator: Bamberger, Joseph A.
System: The UNT Digital Library
2-D Eulerian hydrodynamics with fluid interfaces, self-gravity and rotation (open access)

2-D Eulerian hydrodynamics with fluid interfaces, self-gravity and rotation

The purpose of this paper is to describe in detail the numerical approach we have developed over the past five years for solving 2-dimensional gas-dynamical problems in astrophysics involving inviscid compressible flow, self-gravitation, rotation, and fluid instabilities of the Rayleigh-Taylor and Kelvin-Helmholtz types. The computer code to be described has been applied most recently to modeling jets in radio galaxies (Norman et al. 1981, 1982) and is an outgrowth of a code developed for studying rotating protostellar collapse (Norman, Wilson and Barton 1980; Norman 1980). This basic methodology draws heavily on the techniques and experience of James R. Wilson and James M. LeBlanc of the Lawrence Livermore National Laboratory, and thus the code is designed to be a general purpose 2-D Eulerian hydrocode, and is characterized by a high degree of simplicity, robustness, modularity and speed. Particular emphases of this article are: (1) the recent improvements to the code's accuracy through the use of vanLeer's (1977) monotonic advection algorithm, (2) a discussion of the importance of what we term consistent advection, and (3) a description of a numerical techique for modeling dynamic fluid interfaces in multidimensional Eulerian calculations developed by LeBlanc. 23 refs., 14 figs.
Date: January 1, 1982
Creator: Norman, M.L. & Winkler, K.H.A.
System: The UNT Digital Library
S = -2 dibaryons and hypernuclei (open access)

S = -2 dibaryons and hypernuclei

Future prospects for the exploration of doubly strange hypernuclear systems are evaluated. Such systems may be produced via the double strangeness exchange reactions (K/sup -/,K/sup +/) or (K/sup -/,K/sup 0/) on nuclear targets. Theoretical estimates are given of the formation cross sections for Xi/sup -/ hypernuclear states via the one-step K/sup -/p ..-->.. K/sup +/Xi/sup -/ process, or discrete states of the ..lambda lambda.. hypernucleus in the two step reaction K/sup -/p ..-->.. ..pi../sup 0/..lambda.. followed by ..pi../sup 0/p ..-->.. K/sup +/..lambda... Recently, there has been much discussion of six quark (dibaryon) states in the Bag Model. Arguments are given which indicate that the (K/sup -/,K/sup +/) reaction on light nuclear targets (ex. /sup 3/He) affords a very promising way of producing the lowest-lying S = -2 dibaryon (called the H).
Date: January 1, 1982
Creator: Dover, C.B.
System: The UNT Digital Library
3-D solution of flow in an infinite square array of circular tubes by using boundary-fitted coordinate system (open access)

3-D solution of flow in an infinite square array of circular tubes by using boundary-fitted coordinate system

Heat transfer and fluid flow over circular tubes have wide applications in the design of heat exchangers and nuclear reactors. However, it is often difficult to accurately calculate the detailed velocity and temperature distributions of the flow because of the complex geometry involved in the analysis, and a lack of an appropriate coordinate system for the analysis. Boundary conditions on the surfaces of the tubes are often interpolated. This interpolation process introduces inaccuracy. To overcome this difficulty, the present study used the technique of the boundary-fitted coordinate system. In this technique, all the physical boundaries are transformed into constant coordinate lines in the transformed coordinates. Therefore, the boundary conditions can be specified on the grid points without interpolation.
Date: January 1, 1982
Creator: Chen, B. C. J.; Chien, T. H.; Sha, W. T. & Kim, J. H.
System: The UNT Digital Library
A = 4 0/sup +/ - 1/sup +/ binding-energy difference (open access)

A = 4 0/sup +/ - 1/sup +/ binding-energy difference

The A = 4 ..lambda..-hypernuclei provide a rich source of information about the s-wave properties of the fundamental hyperon-nucleon (YN) force as well as offer a unique opportunity to investigate the complications that arise in calculations of the properties of bound systems in which one baryon (here the ..lambda..) with a given isospin couples strongly to another (the ..sigma..) with a different isospin. The ..lambda../sup 4/H - ..lambda../sup 4/He isodoublet ground-state energies are not consistent with a charge symmetry hypothesis for the YN interaction. The (spin-flip) excitation energies are quite sensitive to the ..lambda..N - ..sigma..N coupling of the YN interaction. In particular, when one represents the free YN interaction in terms of one-channel effective ..lambda..N potentials, the resulting 0/sup +/ (ground) state and 1/sup +/ (excited) spin-flip state are inversely ordered in terms of binding energies, the 1/sup +/ state being more bound. It is the ..sigma.. suppression that results from the reduced strength of the ..lambda..N - ..sigma..N off-diagonal coupling potential when the trinucleon core is restricted to isospin-1/2 which we study here. We find this spin-isospin suppression of the ..lambda..-..sigma.. conversion, which is due to the composite nature of the nuclear cores of the ..lambda../sup 4/H and …
Date: January 1, 1982
Creator: Gibson, B. F. & Lehman, D. R.
System: The UNT Digital Library
1982 engineering conference on reliability for the electrical power industry (open access)

1982 engineering conference on reliability for the electrical power industry

Emergency onsite ac power systems at nuclear power plants are a major concern in plant risk assessments because of the relatively large frequency of loss of offsite power and the dependence of most other safety systems on ac power. Detailed reviews of onsite ac power system designs and reviews of experience with diesel generators at US nuclear power plants form the basis of system reliability analyses that show significant improvements in reliability can be obtained at moderate cost for some plants. Onsite ac power system modifications analyzed include procedural modifications, minor equipment modifications and major equipment additions. Relative costs of various modifications are compared with associated system reliability improvements.
Date: January 1, 1982
Creator: Campbell, D. J.; Arendt, J. S.; Battle, R. E. & Baranowsky, P. W.
System: The UNT Digital Library
1D thermonuclear model for x-ray transients (open access)

1D thermonuclear model for x-ray transients

The thermonuclear evolution of a 1.41 M solar mass neutron star, with a radius of 14.3 km, accreting various mixtures of hydrogen, helium, and heavy elements at rates of 10/sup -11/ to 10/sup -10/ M solar mass/yr is examined, in conjunction with S.E. Woosley and T.A. Weaver, using a one-dimensional numerical model. We have ignored any effects due to general relativity or magnetic fields. Two cases shall be discussed. In both models, the accretion rate is such that the hydrogen shell burns to helium in steady state, with the hydrogen burning stabilized by the ..beta..-limited CNO cycle. A thick helium shell is produced, which is eventually ignited under extremely degenerate conditions, producing a thermonuclear runaway.
Date: January 1, 1982
Creator: Wallace, R. K.
System: The UNT Digital Library
Absolutely calibrated soft-x-ray streak camera for laser-fusion applications (open access)

Absolutely calibrated soft-x-ray streak camera for laser-fusion applications

The intensity output of a soft-x-ray streak camera was calibrated (SXRSC) in order to make absolute flux measurements of x rays emitted from laser-produced plasmas. The SXRSC developed at LLNL is used to time-resolve x-ray pulses to better than 20 ps. The SXRSC uses a Au photocathode on a thin carbon substrate which is sensitive to x rays from 100 eV to greater than 10 keV. Calibrations are done in the dynamic mode using a small laser-produced x-ray source. The SXRSC is calibrated by comparing its integrated signal to the output of calibrated x-ray diodes monitoring the source strength. The measured SXRSC response is linear over greater than two orders of magnitude. Using these calibrations, absolute intensities can be measured to an accuracy of +-30%.
Date: January 1, 1982
Creator: Kauffman, R.L.; Medecki, H. & Stradling, G.
System: The UNT Digital Library
Acceleration of heavy ions to very high energies (open access)

Acceleration of heavy ions to very high energies

The current interest of physicists in the collisions of heavy ions closes an interesting circle in the technology of accelerator building. The first cyclic accelerator, built by R. Wideroe, was a linear accelerator designed to accelerate potassium ions. Subsequent to Wideroe's achievement, much of the art of accelerator construction has been devoted to creating energetic beams of electrons and protons. Now we find ourselves returning to the heavy ions, and Wideroe's linear accelerator structure still plays an important role in many acceleration schemes. Fortunately, while the particle physics community has concentrated on the electron and proton machines, the nuclear physicists have kept alive the interest in heavy ions. Now a host of electrostatic machines, cyclotrons, and heavy ion linear accelerators provide beams of all species of ions at energies from about 100 MeV per nucleon for light isotopes to 10 MeV per nucleon for the heaviest isotopes in support of vigorous physics programs.
Date: January 1, 1982
Creator: Barton, M. Q.
System: The UNT Digital Library
Accident analysis and DOE criteria (open access)

Accident analysis and DOE criteria

In analyzing the radiological consequences of major accidents at DOE facilities one finds that many facilities fall so far below the limits of DOE Order 6430 that compliance is easily demonstrated by simple analysis. For those cases where the amount of radioactive material and the dispersive energy available are enough for accident consequences to approach the limits, the models and assumptions used become critical. In some cases the models themselves are the difference between meeting the criteria or not meeting them. Further, in one case, we found that not only did the selection of models determine compliance but the selection of applicable criteria from different chapters of Order 6430 also made the difference. DOE has recognized the problem of different criteria in different chapters applying to one facility, and has proceeded to make changes for the sake of consistency. We have proposed to outline the specific steps needed in an accident analysis and suggest appropriate models, parameters, and assumptions. As a result we feed DOE siting and design criteria will be more fairly and consistently applied.
Date: January 1, 1982
Creator: Graf, Joseph M. & Elder, John C.
System: The UNT Digital Library
Acoustic disturbance at ionospheric heights caused by the MILL RACE explosion (open access)

Acoustic disturbance at ionospheric heights caused by the MILL RACE explosion

The principal objective of the Los Alamos National Laboratory in the MILL RACE experiment was to measure the over-head ionospheric response due to the MILL RACE explosion. Such a measurement enables one to test computer models designed to quantitatively predict ionospheric disturbances caused by known sources. The emphasis of the models has been directed at calculating effects on rf propagation associated with the predicted ionospheric disturbances. Consequently vertical incidence phase sounding measurements of a well-characterized source provide a direct and sensitive test of the computer models and, for this reason, a vertical incidence phase sounder was located 3300 meters to the west of the MILL RACE ground zero. Another area of interest is the development of an understanding of the atmospheric response to known sources at distances where the acoustic response no longer dominates. Such an undertaking requires measurements at these remote points. Deployment of a bistatic sounding network enabled the investigation of this area of interest. Results are reported.
Date: January 1, 1982
Creator: Rickel, D.G. & Simons, D.J.
System: The UNT Digital Library
ACTAS/Proceedings: Volume 2 (open access)

ACTAS/Proceedings: Volume 2

Separate abstracts have been prepared for the 17 original papers and their translations included. (ACR)
Date: January 1, 1982
Creator: unknown
System: The UNT Digital Library
Adiabatic compression of elongated field-reversed configurations (open access)

Adiabatic compression of elongated field-reversed configurations

The simplest model of plasma dynamics is the adiabatic model. In this model the plasma is assumed to be in MHD equilibrium at each instant of time. The equilibria are connected by the requirement that they all have the same entropy per unit flux, i.e., the equilibria form a sequence generated by adiabatic changes. The standard way of computing such a sequence of equilibria was developed by Grad, but its practical use requires a fairly complicated code. It would be helpful if approximately the same results could be gotten either with a much simpler code or by analytical techniques. In Sec. II a one-dimensional equilibrium code is described and its results are checked against a two-dimensional equilibrium code; in Sec. III an even simpler analytic calculation is presented.
Date: January 1, 1982
Creator: Spencer, R.L.; Tuszewski, M. & Linford, R.K.
System: The UNT Digital Library
Adiabatic invariants for field-reversed configurations (open access)

Adiabatic invariants for field-reversed configurations

Field reversed configurations (FRCs) are characterized by azimuthal symmetry, so two exact constants of the particle motion are the total particle energy E and the canonical angular momentum P/sub theta/. For many purposes it is desirable to construct a third (diabatic) constant of the motion if this is possible. It is shown that for parameters characteristic of current FRCs that the magnetic moment ..mu.. is a poor adiabatic invariant, while the radial action J is conserved rather well.
Date: January 1, 1982
Creator: Schwarzmeier, J. L.; Lewis, H. R. & Seyler, C. E.
System: The UNT Digital Library
Advanced design of positive-ion sources for neutral-beam applications (open access)

Advanced design of positive-ion sources for neutral-beam applications

The APIS ion source is being developed to meet a goal of producing ion beams of less than or equal to 200 keV, 100 A, with 10-30-s pulse lengths. In a continuing effort to advance the state of the art and to produce long pulse ion beams, APIS ion sources with grid dimensions of 10 x 25 cm, 13 x 43 cm, and 16 x 48 cm are being developed. In the past year, the 10- x 25-cm ion source has been operated to produce ion beams in excess of 100 keV for many seconds pulse length. An advanced design concept is being pursued with the primary objectives to improve radiation protection, reduce fabrication costs, and simplify maintenance. The source magnetic sheild will be designed as a vacuum enclosure to house all source components. The electrical insulation requirements of energy recovery are also considered. Because of the frequent maintenance requirements, the electron emitter assembly will be designed with a remote handling capability. A new accelerator design which incorporates the necessary neutron shielding and associated steering gimbal system is also described.
Date: January 1, 1982
Creator: Marguerat, E. F.; Haselton, H. H.; Menon, M. M.; Schechter, D. E.; Stirling, W. L. & Tsai, C. C.
System: The UNT Digital Library
Advances in measurement of alpha-contaminated wastes (open access)

Advances in measurement of alpha-contaminated wastes

A comprehensive program is in progress at the Los Alamos National Laboratory for the development of sensitive, practical, nondestructive assay techniques for the quantification of low-level transuranics in bulk solid wastes. The program encompasses a broad range of techniques, including sophisticated active and passive gamma-ray spectroscopy, passive neutron detection systems, pulsed portable neutron generator interrogation systems, and electron accelerator-based techniques. The techniques can be used with either low-level or high-level beta-gamma wastes in either low-density or high-density matrices.
Date: January 1, 1982
Creator: Close, D. A.; Crane, T. W.; Caldwell, J. T.; Kunz, W. E.; Shunk, E. R.; Pratt, J. C. et al.
System: The UNT Digital Library
AEGIS methodology demonstration: case example in basalt (open access)

AEGIS methodology demonstration: case example in basalt

The AEGIS technology has been successfully demonstrated. For the same data, similar unpublished results have been obtained by RHO and INTERA Environmental Consultants, Inc. for contaminant transport. In addition to establishing the utility of computer codes and assessment methodology, the AEGIS technology demonstration in basalt has also produced some practical guidance for future field data gathering programs. The results of this basalt demonstration indicate that the geohydrologic systems separating the nuclear waste from the natural biosphere discharge site mitigate the consequences of the postulated fault intersection event. This analysis suggests that the basalt system satisfies the 1000- and 10,000-yr proposed standards for release to the accessible environment (limited release of /sup 129/I and /sup 14/C). The reader should be cautioned, however, that the results are valid only for one particular set of parameters and one postulated release scenario. A complete sensitivity analysis must be performed to evaluate the range of effects that might be observed under different release conditions and for the different range in parameters.
Date: January 1, 1982
Creator: Dove, F. Harvey
System: The UNT Digital Library
Air-over-ground calculations of the neutron, prompt, and secondary-gamma free-in-air tissue kerma from the Hiroshima and Nagasaki devices (open access)

Air-over-ground calculations of the neutron, prompt, and secondary-gamma free-in-air tissue kerma from the Hiroshima and Nagasaki devices

This paper reports preliminary results of the two-dimensional discrete-ordinate, calculations for the air-over-ground transport of radiation from the Hiroshima and Nagasaki weapon devices. It was found that the gamma-ray kerma dominated the total kerma for both environments.
Date: January 1, 1982
Creator: Pace, J. V. III; Knight, J. R. & Bartine, D. E.
System: The UNT Digital Library
Los Alamos DP West Plutonium Facility decontamination project (open access)

Los Alamos DP West Plutonium Facility decontamination project

The DP West Plutonium Facility operated by the Los Alamos National Laboratory, Los Alamos, New Mexico, was decontaminated between April 1978 and April 1981. The facility was constructed in 1944 to 1945 to produce plutonium metal and fabricate parts for nuclear weapons. It was continually used as a plutonium processing and research facility until mid-1978. Decontamination operations included dismantling and removing gloveboxes and conveyor tunnels; removing process systems, utilities, and exhaust ducts; and decontaminating all remaining surfaces. This report describes glovebox and conveyor tunnel separations, decontamination techniques, health and safety considerations, waste management procedures, and costs of the operation.
Date: January 1, 1982
Creator: Garde, R.; Cox, E.J. & Valentine, A.M.
System: The UNT Digital Library
Los Alamos Hot-Cell-Facility modifications for examining FFTF fuel pins (open access)

Los Alamos Hot-Cell-Facility modifications for examining FFTF fuel pins

Commissioned in 1960, the Wing 9 Hot Cell Facility at Los Alamos was recently modified to meet the needs of the 1980s. Because fuel pins from the Fast Flux Test Facility (FFTF) at the Hanford Engineering Development Laboratory (HEDL) are too long for examination in the original hot cells, we modified cells to accommodate longer fuel pins and to provide other capabilities as well. For instance, the T-3 shipping cask now can be opened in an inert atmosphere that can be maintained for all nondestructive and destructive examinations of the fuel pins. The full-length pins are visually examined and photographed, the wire wrap is removed, and fission gas is sampled. After the fuel pin is cropped, a cap is seal-welded on the section containing the fuel column. This section is then transferred to other cells for gamma-scanning, radiography, profilometry, sectioning for metallography, and chemical analysis.
Date: January 1, 1982
Creator: Campbell, B. M. & Ledbetter, J. M.
System: The UNT Digital Library
Los Alamos National Laboratory solar program (open access)

Los Alamos National Laboratory solar program

Progress is reported for passive solar tasks performed at the Los Alamos National Laboratory during FY 1982. Results on test cell experiments for the 1981-1982 winter are reported, as are Class A performance monitoring, passive cooling, both residential and commercial economic cooling assessments, and thermal effects of distributed mass in passive buildings.
Date: January 1, 1982
Creator: Reisfeld, S.K. & Neeper, D.A.
System: The UNT Digital Library