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International training course on nuclear materials accountability for safeguards purposes

Description: The two volumes of this report incorporate all lectures and presentations at the International Training Course on Nuclear Materials Accountability and Control for Safeguards Purposes, held May 27-June 6, 1980, at the Bishop's Lodge near Santa Fe, New Mexico. The course, authorized by the US Nuclear Non-Proliferation Act and sponsored by the US Department of Energy in cooperation with the International Atomic Energy Agency, was developed to provide practical training in the design, implementation, and operation of a National system of nuclear materials accountability and control that satisfies both National and IAEA International safeguards objectives. Volume I, covering the first week of the course, presents the background, requirements, and general features of material accounting and control in modern safeguard systems. Volume II, covering the second week of the course, provides more detailed information on measurement methods and instruments, practical experience at power reactor and research reactor facilities, and examples of operating state systems of accountability and control.
Date: December 1, 1980
Partner: UNT Libraries Government Documents Department

Ionospheric effects of rocket exhaust products (HEAO-C, Skylab and SPS-HLLV)

Description: This paper reviews the current state of our understanding of the problem of ionospheric F-layer depletions produced by chemical effects of the exhaust gases from large rockets, with particular emphasis on the Heavy Lift Launch Vehicles (HLLV) proposed for use in the construction of solar power satellites. The currently planned HLLV flight profile calls for main second-stage propulsion confined to altitudes below 124 km, and a brief orbit-circularization maneuver at apogee. The second-stage engines deposit 9 x 10/sup 31/ H/sub 2/O and H/sub 2/ molecules between 56 and 124 km. Model computations show that they diffuse gradually into the ionospheric F region, where they lead to weak but widespread and persistent depletions of ionization and continuous production of H atoms. The orbit-circularization burn deposits 9 x 10/sup 29/ exhaust molecules at about 480-km altitude. These react rapidly with the F2 region 0/sup +/ ions, leading to a substantial (factor-of-three) reduction in plasma density, which extends over a 1000- by 2000-km region and persists for four to five hours. Also described are experimental airglow and incoherent-scatter radar measurements performed in conjunction with the 1979 launch of satellite HEAO-C, together with prelaunch and post-launch computations of the ionospheric effects. Several improvements in the model have been driven by the experimental observations. The computer model is described in some detail.
Date: October 1, 1980
Creator: Zinn, J; Sutherland, D; Stone, S N; Duncan, L M & Behnke, R
Partner: UNT Libraries Government Documents Department

Homogeneous nucleation: a problem in nonequilibrium quantum statistical mechanics

Description: The master equation for cluster growth and evaporation is derived for many-body quantum mechanics and from a modified version of quantum damping theory used in laser physics. For application to nucleation theory, the quantum damping theory is generalized to include system and reservoir states that are not separate entities. Formulas for rate constants are obtained. Solutions of the master equation yield equations of state and system-averaged quantities recognized as thermodynamic variables. Formulas for Helmholtz free energies of clusters in a Debye approximation are derived. Coexistence-line equations for pressure, volume, and number of clusters are obtained from equations-of-state analysis. Coexistence-line and surface-tension data are used to obtain values of parameters for the Debye approximation. These data are employed in calculating both the nucleation current in diffusion cloud chamber experiments and the onset of condensation in expansion nozzle experiments. Theoretical and experimental results are similar for both cloud chamber and nozzle experiments, which measure water. Comparison with other theories reveals that classical theory only accidently agrees with experiment and that the Helmholtz free-energy formula used in the Lothe--Pound theory is incomplete. 27 figures, 3 tables, 149 references.
Date: August 1, 1978
Partner: UNT Libraries Government Documents Department

Publications of LASL research

Description: LASL now devotes about one-half of its total effort to unclassified research exploring several peaceful applications of nuclear and other forms of energy. LASL research covers a broad spectrum, ranging from medium-energy, low-energy, and high-energy nuclear physics research to programs involving medical and biological effects of radiation and basic work in molecular and cellular biology. Major nonweapons research activities at Los Alamos involve energy research in fields such as superconducting electrical energy transmission and storage, solar and geothermal energy development, laser fusion research and laser isotope separation, and controlled thermonuclear research using magnetic confinement. Facilities used in such research at the Laboratory include specialized laboratories, a nuclear reactor designed for a variety of experiments, particle accelerators such as the 24-MeV Van de Graaff and LAMPF, Scyllac, and a central computing facility. LASL, as of 1977, employed about 6,000 persons, about one-third of whom are scientists and engineers. The total operating costs are about $250 million per year. (RWR)
Date: January 1, 1977
Partner: UNT Libraries Government Documents Department

TRAC-P1: an advanced best estimate computer program for PWR LOCA analysis. I. Methods, models, user information, and programming details

Description: The Transient Reactor Analysis Code (TRAC) is being developed at the Los Alamos Scientific Laboratory (LASL) to provide an advanced ''best estimate'' predictive capability for the analysis of postulated accidents in light water reactors (LWRs). TRAC-Pl provides this analysis capability for pressurized water reactors (PWRs) and for a wide variety of thermal-hydraulic experimental facilities. It features a three-dimensional treatment of the pressure vessel and associated internals; two-phase nonequilibrium hydrodynamics models; flow-regime-dependent constitutive equation treatment; reflood tracking capability for both bottom flood and falling film quench fronts; and consistent treatment of entire accident sequences including the generation of consistent initial conditions. The TRAC-Pl User's Manual is composed of two separate volumes. Volume I gives a description of the thermal-hydraulic models and numerical solution methods used in the code. Detailed programming and user information is also provided. Volume II presents the results of the developmental verification calculations.
Date: May 1, 1978
Partner: UNT Libraries Government Documents Department

Magnetic induction technique for mapping vertical conductive fractures: theory of operation

Description: Utilization of a hot dry rock geothermal resource requires circulation of a fluid (water) through fractures in the rock. The Los Alamos Scientific Laboratory is presently investigating the feasibility and economics of tapping this energy resource. Presently, the fractures in the rock are created by conventional hydraulic fracturing techniques. Accurate determination of the geometry of the fracture system is required so that boreholes may be drilled to complete the circulation system. The theory of a technique designed to map vertical conductive fractures located in resistive rock is presented. The technique is based on magnetic induction. Fracture thickness and strike can be determined from measurements made in a single borehole.
Date: July 1, 1978
Partner: UNT Libraries Government Documents Department

800-MeV spin precessor for polarized H/sup -/ beams using H/sup -/ to H/sup 0/ stripping

Description: A new method is described for precessing the proton polarization axis of the incident H/sup -/ polarized beam at LAMPF. The method uses a thin stripper to convert H/sup -/ to H/sup 0/ with approx. 50% efficiency at 800 MeV, and uses relatively small magnets to precess the H/sup 0/ spin. The large magnetic moment of the H/sup 0/ relative to the charged ion (either H/sup +/ or H/sup -/) allows small magnets to produce any required spin orientation (with zero deflection of the neutral beam in the precession apparatus). Either H/sup 0/ or H/sup +/ beam is delivered; for H/sup 0/, the magnitude of the proton polarization oscillates in proper time at the hyperfine frequency. The theory and test results will be summarized. Areas of possible application will be mentioned, including use for experiments and spin axis control where neutral beams can be used for injection of accelerated H/sup -/ beams into storage rings or synchrotrons.
Date: January 1, 1979
Creator: van Dyck, O.B.
Partner: UNT Libraries Government Documents Department

870. 8-keV gamma ray from PuO/sub 2/

Description: A /sup 252/Cf neutron source and an /sup 241/Am alpha source were used with isotopically enriched water containing 43.9% /sup 17/O and 43.1% /sup 18/O, to study the (n,n'UPSILON) and (..cap alpha..,..cap alpha..'UPSILON) reactions in /sup 17/O and /sup 18/O. The production yields for the 870.8-keV gamma ray from /sup 17/O and the 1982.2-keV gamma ray from /sup 18/O were measured. In addition, the average cross sections over the /sup 252/Cf fission neutron spectrum for /sup 17/O(n,n'UPSILON)/sup 17/O and /sup 18/O(n,n'UPSILON)/sup 18/O were determined.
Date: January 1, 1981
Creator: Hsu, H.H.
Partner: UNT Libraries Government Documents Department

9519 biotite granodiorite reacted in a temperature gradient

Description: A biotite granodiorite from the Fenton Hill Hot Dry Rock (HDR) geothermal system was reacted in a controlled temperature gradient with initially distilled water for 60d. Polished rock prisms were located in the gradient at 72, 119, 161, 209, 270, and 310/sup 0/C. Scanning electron microscope and microprobe analyses show the appearance of secondary phases: Ca-montmorillonite at 72/sup 0/C and 119/sup 0/C; zeolite, either stilbite or heulandite, at 161/sup 0/C; and another zeolite, thomsonite, at higher temperatures. Solution analyses show a steady state equilibrium exists between solution and overgrowths after about 2 weeks of reaction. The chemographic relations for the system are explored in some detail indicating the divariant assemblages may be placed in a reasonable sequence in intensive variable space. These relations predict high and low temperature effects not directly observed experimentally as well as relevant univariant equilibria. Solution chemistry indicates the Na-Ca-K geothermometer more adequately predicts temperature in this system than does the silica geothermometer.
Date: October 1, 1980
Creator: Charles, R.W. & Bayhurst, G.K.
Partner: UNT Libraries Government Documents Department

30-MJ superconducting magnetic energy storage (SMES) unit for stabilizing an electric transmission system

Description: Electric power systems that have major loads and generation centers separated by large distances may experience low-frequency power oscillations. This type of oscillation has occurred on the Pacific ac intertie that connects southern California and the Pacific Northwest. A separate, almost parallel, dc-transmission line also connects these areas. The Bonneville Power Administration, which operates this transmission system, has overcome the instability by controlling the power transmitted on the dc-transmission line. A 30-MJ (8.4-kWh) superconducting magnetic energy storage unit with a 10-MW converter could also provide damping for this instability. The conceptual design of the 30-MJ coil and the cryogenic and electrical components of the system are described. The system is to operate at a maximum current of 5 kA and will modulate the ac Intertie at 0.35 Hz. Discharge will be controlled to retain a minimum stored energy of 20 MJ to limit cyclic strains in the coil and ac losses in the conductor. The conductor will be made of multistrand-copper and copper-matrix, multifilament NbTi superconducting wires on a stainless steel mandrel.
Date: January 1, 1978
Creator: Rogers, J.D.; Boenig, H.J.; Bronson, J.C.; Colyer, D.B.; Hassenzahl, W.V.; Turner, R.D. et al.
Partner: UNT Libraries Government Documents Department

60-inch annular pitch polisher for LASL's LASER-fusion effort

Description: The Antares laser will require that about 100 high-precision NaCl windows of 18-in. diameter be produced, maintained, and repaired. To aid the industry in achieving the required production rates, a polishing development program was undertaken by LASL's Laser Division in collaboration with the Air Force and International Laser Systems. The design and initial shakedown of the polishing machine is described. Preliminary results indicate the machine's design is sound, its operation is generally simple, and it should be capable of finishing 18-in. NaCl to better than lambda/2 visible and 20-10 surface. Shakedown work with glass has demonstrated 0-0 surface, complete absence of edge roll, and lambda/16 over 12 in., and lambda/6 over 19 in.
Date: November 9, 1978
Creator: Williamson, R.
Partner: UNT Libraries Government Documents Department

Heat transfer in the lithium-cooled blanket of a pulsed fusion reactor

Description: The transient temperature distribution in the lithium-cooled blanket of a pulsed fusion reactor has been calculated using a finite-element heat-conduction computer program. An auxiliary program was used to predict the coolant transient velocity in a network of parallel and series flow passages with constant driving pressure and varying magnetic field. The coolant velocity was calculated by a Runge-Kutta numerical integration of the conservation equations. The lithium coolant was part of the finite-element heat-conduction mesh with the velocity terms included in the total matrix. The matrix was solved implicitly at each time step for the nodal point temperatures. Slug flow was assumed in the coolant passages and the Boussinesq analogy was used to calculate turbulent heat transfer when the magnetic field was not present.
Date: January 1, 1978
Creator: Cort, G.E. & Krakowski, R.A.
Partner: UNT Libraries Government Documents Department

Fast transient absorption in optical fibers

Description: Transient absorption in optical fibers was studied with 2 ns resolution. The data show a very fast absorption peak (with little temperature dependence) superimposed on a slow, temperature dependent, recovery.
Date: January 1, 1981
Creator: Lyons, P.B.; Looney, L.D. & Kelly, R.E.
Partner: UNT Libraries Government Documents Department

Feasibility of Zircaloy as a fuel clad and structural material in an LAFR-LWR

Description: A preliminary analysis of the radiation environment in a Linear Accelerator Fuel Regenerator (LAFR) has been made. The response of Zircaloy to this environment in combination with that in a Light Water Reactor (LWR) has been projected. It is concluded that the response to irradiation of Zircaloy in a combined LAFR-LWR cycle will lead to a more deleterious change of properties than for an equivalent LWR exposure.
Date: January 1, 1979
Creator: Parkin, D.M.
Partner: UNT Libraries Government Documents Department

Experimental investigation of heating phenomena in linac mechanical interfaces due to RF field penetration

Description: In a high duty-factor, high-current, drift-tube linear accelerator, a critical interface exists between the drift-tube stem and the tank wall. This interface must provide vacuum integrity and RF continuity, while simultaneously allowing alignment flexibility. Because of past difficulties with RF heating of vacuum bellows and RF joints encountered by others, a paucity of available information, and the high reliability requirement for the Fusion Materials Irradiation Test (FMIT) accelerator, a program was initiated to study the problem. Because RF heating is the common failure mode, an attempt was made to find a correlation between the drift-tube-stem/linac-tank interface geometry and RF field penetration from the tank into the interface region. Experiments were performed at 80 MHz on an RF structure designed to simulate the conditions to which a drift-tube stem and vacuum bellows are exposed in a drift-tube linac. Additional testing was performed on a 367-MHz model of the FMIT prototype drift-tube linac. Experimental results, and a method to predict excessive RF heating, is presented. An experimentally tested solution to the problem is discussed.
Date: January 1, 1981
Creator: Fazio, M.V.; Reid, D.W. & Potter, J.M.
Partner: UNT Libraries Government Documents Department

Explosive flux compression generators for rail gun power sources

Description: A class of explosive magnetic flux compression generators is described that has been used successfully to power rail guns. A program to increase current magnitudes and pulse lengths is outlined. Various generator loss terms are defined and plans to overcome some of them are discussed. Included are various modifications of the conventional strip generators that are more resistant to undesirable expansion of generator components from magnetic forces. Finally, an integral rail gun is discussed that has coaxial geometry. Integral rail guns utilize the rails themselves as flux compression generator elements and, under ideal conditions, are theoretically capable of driving projectiles to arbitrarily high velocities. Integral coaxial rail guns should be superior in some regards to their square bore counterparts.
Date: January 1, 1980
Creator: Fowler, C.M.; Peterson, D.R.; Caird, R.S.; Erickson, D.J.; Freeman, B.L. & King, J.C.
Partner: UNT Libraries Government Documents Department

Extended likelihood inference in reliability

Description: Extended likelihood methods of inference are developed in which subjective information in the form of a prior distribution is combined with sampling results by means of an extended likelihood function. The extended likelihood function is standardized for use in obtaining extended likelihood intervals. Extended likelihood intervals are derived for the mean of a normal distribution with known variance, the failure-rate of an exponential distribution, and the parameter of a binomial distribution. Extended second-order likelihood methods are developed and used to solve several prediction problems associated with the exponential and binomial distributions. In particular, such quantities as the next failure-time, the number of failures in a given time period, and the time required to observe a given number of failures are predicted for the exponential model with a gamma prior distribution on the failure-rate. In addition, six types of life testing experiments are considered. For the binomial model with a beta prior distribution on the probability of nonsurvival, methods are obtained for predicting the number of nonsurvivors in a given sample size and for predicting the required sample size for observing a specified number of nonsurvivors. Examples illustrate each of the methods developed. Finally, comparisons are made with Bayesian intervals in those cases where these are known to exist.
Date: October 1, 1978
Creator: Martz, H.F. Jr.; Beckman, R.J. & Waller, R.A.
Partner: UNT Libraries Government Documents Department

Gyrocon Radio-Frequency-Generator project for FY-78 and -79

Description: The gyrocon is a high-power, high-efficiency amplifier that operates by deflection modulation of an electron beam. The bunching is better than that in a klystron, especially for very high powers and UHF frequencies, so the overall efficiency and the maximum output power can be higher than in a klystron. The present theory includes the effects of large signals, space charge, and finite beam size. The equations of motion are relativistically correct, and the space-charge fields are correct to first order in v/c. The theory is derived and a computer code to solve these equations is discussed. The code is then used to obtain several specific examples of gyrocon designs that have significant advantages over klystrons or gridded tubes in the 0.2- to 1.0-GHz frequency range. Several embodiments of the gyrocon are possible: the radial style and the spherical style are discussed in this report. The radial style has a bender magnet to increase the deflection of the beam, whereas the spherical gyrocon does not employ the bender magnet. The optimum frequency range for the spherical gyrocon is from 1.0 to 2.5 GHz.
Date: September 1, 1980
Creator: Tallerico, P.J. & Rankin, J.E.
Partner: UNT Libraries Government Documents Department

High pressure study of ferromagnetic US

Description: The variation of the ac magnetic susceptibility of a polycrystalline ferromagnet US as a function of hydrostatic pressure was investigated. The Curie temperature decreases linearly from 180.0/sup 0/K at the atmospheric pressure to 175.9/sup 0/K at 17.6 kbar.
Date: January 1, 1978
Creator: Huang, C.Y.; Laskowski, R.J.; Olsen, C.E. & Smith, J.L.
Partner: UNT Libraries Government Documents Department

High-radiation-zone design of the FMIT high-energy beam transport

Description: The Fusion Materials Irradiation Test (FMIT) deuteron linac, operating at 35 MeV and 100 mA continuous duty, is expected to spill 3 ..mu..A/m and to lose 10 ..mu..A at specific bending-magnet positions. The major impact of this spill will be felt in the High-Energy Beam Transport (HEBT), where many beam-line components must be maintained. A modular design concept, that uses segmented termination panels remotely located from the modules, is being employed. Radiation-hardened quadrupoles can be opened, clamshell fashion, to release the water-cooled beam tube replacement if there is beam damage or lithium contamination from the target. Termination panels contain electrical, water, and instrumentation fittings to service the module, and are positioned to allow room for neutron-absorbing shielding between the beamline and the panel. The modular construction allows laboratory prealignment and check-out of all components on a structural carriage and is adaptable to supporting gamma shields.
Date: January 1, 1981
Creator: Liska, D.J.; King, J.D.; Cole, T.R.; Cimabue, A.G.; Robeson, L.P.; Creek, K.O. et al.
Partner: UNT Libraries Government Documents Department

Further studies of long-term ecological effects of exposure to uranium

Description: Spatial variability in sampling for soil uranium distribution by a polar coordinate system was evaluated in randomly selected soil cores at the Los Alamos Scientific Laboratory. Variations for surface (0- to 2.5-cm-deep) soils were 0.18 at 10 m from the nuclear weapons test detonation point and 0.96 at 50 m. Results were strongly influenced by past uranium dispersal patterns, variable leaching of uranium debris, and surface water runoff. A total surface (0- to 5-cm) soil uranium inventory within a 12.6-ha circle centered on the E-F detonation point was estimated to be 3000 kg when calculated by soil uranium concentration isopleths and 4500 kg when using annuli of a polar coordinate sampling system. Uranium concentrations in tissues of deer mice (Peromyscus maniculatus) and pocket gophers (Thomomys bottae) were sufficiently different to conclude that the greater bioavailability of uranium in the top few millimeters of soil at E-F Site, combined with the difference in grooming and food habits of the animals, resulted in greater contamination of deer mice than of pocket gophers.
Date: July 1, 1978
Creator: Hanson, W.C. & Miera, F.R. Jr.
Partner: UNT Libraries Government Documents Department

High-performance graphics system for the CRAY-1

Description: The design and implementation of a state-of-the-art interactive vector graphics system connected to the CRAY-1 supercomputer are described. The primary design goal for this graphics system is that it supports large hydrodynamic computer programs used in weapons design calculations. The interactive use of these programs requires displays consisting of up to 20,000 vectors, extensive interaction tools, and high-bandwidth communication rates. The major system components selected for this project were an Evans and Sutherland Picture System 2 and a Digital Equipment Corporation (DEC) PDP-11/70 and PDP-11/34 running the UNIX operating system. The system design goals and performance criteria are presented. The hardware/software systems chosen for this project are reviewed, and the integration of this system into the Los Alamos Scientific Laboratory's Integrated Computer Network is described. This implementation involved most areas of applied computing, including computer graphics, communications, distributed processing, and computer security. The level of effort required for this implementation is described, and the results and benefits are presented. Future plans for this system are also briefly described. 3 figures, 2 tables.
Date: January 1, 1978
Creator: Ewald, R.H. & Maas, L.D.
Partner: UNT Libraries Government Documents Department