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2-D Axisymmetric Line Transport

Description: The methods used in the ALTAIR code for computing the transfer of spectral line radiation in two-dimensional axially-symmetric geometry are described. ALTAIR uses a variable-Eddington-tensor approach, in which the transfer equation of non-coherent line scattering is written in moment form, and the moments are closed with an assumed tensor relating the monochromatic pressure tensor and energy density; this Eddington tensor is obtained self-consistently using an accurate angle-dependent solution … more
Date: November 20, 1990
Creator: Castor, John I.; Dykema, Pieter G. & Klein, Richard I.
Partner: UNT Libraries Government Documents Department
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2 MW 110 GHz ECH heating system for DIII-D

Description: A 2 MW 110 GHz ECH system using Varian 0.5 MW gyrotrons is under construction for use on the DIII-D tokamak by late 1991. Most of the components are being design and fabricated at General Atomics, including the gyrotron tanks, superconducting magnets, and transmission line. These components are intended for operation with 10 second pulses and, in the future, with 1 MW gyrotrons. 6 refs., 5 figs.
Date: September 1990
Creator: Moeller, C.; Prater, R.; Callis, R.; Remsen, D.; Doane, J.; Cary, W. et al.
Partner: UNT Libraries Government Documents Department
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3 Dimensional radiation transport in dispersive media

Description: In plasmas the collective motion of free electrons affects the propagation of radiation by bending the light ray trajectory. The closer the light wave frequency is to the electron plasma frequency in value, the more pronounced the effect. We will present the results of radiation transport calculations in 3 spatial dimensions in the refractive plasma environment and compare the calculation to one done where the ray bending has been neglected (straight line ray paths). We also present the numeric… more
Date: November 1, 1990
Creator: Mayle, R.W.
Partner: UNT Libraries Government Documents Department
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A 4. pi. tracking TPC magnetic spectrometer for RHIC

Description: The primary physics objective of the 4{pi} TPC magnetic spectrometer proposal is to search for the Quark-Gluon Plasma. In previous workshops we have discussed what the possible hadronic signatures of such a state of matter would be. Succinctly, the QGP is a direct prediction of non-perturbative QCD. Therefore the question of the existence of this new state of matter bears directly on the validity of non-perturbative QCD. However, since non-perturbative QCD has never been established, it is appa… more
Date: January 1, 1990
Creator: Danby, G.; Eiseman, S. E.; Etkin, A.; Foley, K. J.; Hackenburg, R. W.; Longacre, R. S. et al.
Partner: UNT Libraries Government Documents Department
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A 15 MeV proton diagnostic for DIII-D

Description: A 15 MeV proton diagnostic that is patterned after the ASDEX proton probe is presently being fabricated for the DIII-D tokamak. A bellows assembly inserts a silicon detector into the vacuum for plasma operation and retracts it for baking. The detector preamplifier is situated in a reentrant tube (at atmosphere) beside the detector; electrically, the whole assembly is referenced to vessel potential. Orbit calculations in realistic magnetic field geometries predict a proton detection efficiency o… more
Date: October 1, 1990
Creator: Duong, Hau & Heidbrink, W.W. (California Univ., Irvine, CA (USA))
Partner: UNT Libraries Government Documents Department
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30+ years of plasma simulation

Description: No Description Available.
Date: December 19, 1990
Creator: Langdon, B.
Partner: UNT Libraries Government Documents Department
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A 40 mm bore quadrupole magnet for the SSC

Description: A 40 mm bore quadrupole magnet design, called QC'', has been made for the SSC with the following parameters: 208 T/m gradient at 6500A, 2-layer cos 2 {theta}'' winding arrangement with 30 strand cable and one spacer wedge per coil. Structural support is provided by self-supporting interlocking collars; two types of symmetrical laminations are pre-assembled into collar packs for ease of assembly. This paper will describe the design of a prototype quadrupole magnet for the SSC and preliminary tes… more
Date: September 1, 1990
Creator: Taylor, C.E.; Barale, P.; Caspi, S.; Dell'Orco, D.; Fritz, D.; Gilbert, W.S. et al.
Partner: UNT Libraries Government Documents Department
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50 kA, 50 kV DC international and switching systems for the Los Alamos ZTH experiment

Description: Los Alamos National Laboratory has completed the engineering design and development for the high power electrical switching networks for the ZTH experiment. ZTH is Reversed Field Pinch (RFP) plasma experiment with a 4 MA plasma current capability. Power to the ohmic heating (OH), equilibrium field (EF), and toroidal field (TF) coils will be provided from a 1.43 GVA turbo-alternator, which has over 600 MJ of extractable energy. The DC interrupting switch will handle 2.4 GVA, 150 MJ during initia… more
Date: January 1, 1990
Creator: Reass, W. A.; Cordova, R. J. & Garcia, J. G.
Partner: UNT Libraries Government Documents Department
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A 250-GHz CARM (Cyclotron Auto Resonance Maser) oscillator experiment driven by an induction linac

Description: A 250-GHz Cyclotron Auto Resonance Maser (CARM) oscillator has been designed and constructed and will be tested using a 1-kA, 2-MeV electron beam produced by the induction linac at the Accelerator Research Center (ARC) facility of Lawrence Livermore National Laboratory (LLNL). The oscillator circuit was made to operate in the TE{sub 11} mode at ten times cutoff using waveguide Bragg reflectors to create an external cavity Q of 8000. Theory predicts cavity fill times of less than 30 ns (pulse le… more
Date: September 14, 1990
Creator: Caplan, M.; Kulke, B.; Bubp, D.G. (Lawrence Livermore National Lab., CA (USA)); McDermott, D. & Luhmann, N. (California Univ., Los Angeles, CA (USA))
Partner: UNT Libraries Government Documents Department
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810 Future plans

Description: It is believed that a good bet for finding the Quark-Gluon Plasma at AGS energies is with the heaviest projectiles on the heaviest target, i.e. Au on Au. One of the likely signatures of the plasma is strangeness enhancement. Al Saulys has shown what it's like to find {Delta} and K{degree} with Si projectiles. Our Monte Carlo simulations show track densities 4 times higher for Au projectiles. In addition, the Au beam itself produces 30 times more ionization. Thus the present TPC's will be limite… more
Date: March 27, 1990
Creator: Etkin, A.; Foley, K. J.; Hackenburg, R. W.; Longacre, R. S.; Love, W. A.; Morris, T. W. et al.
Partner: UNT Libraries Government Documents Department
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1990 DOE/SANDIA crystalline photovoltaic technology project review meeting

Description: This document serves as the proceedings for the annual project review meeting held by Sandia's Photovoltaic Cell Research Division and Photovoltaic Technology Division. It contains information supplied by each organization making a presentation at the meeting, which was held August 7 through 9, 1990 at the Sheraton Hotel in Albuquerque, New Mexico. Sessions were held to discuss national photovoltaic programs, one-sun crystalline silicon cell research, concentrator silicon cell research, concent… more
Date: July 1, 1990
Creator: Ruby, D. S.
Partner: UNT Libraries Government Documents Department
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1990 fuel cell seminar: Program and abstracts

Description: This volume contains author prepared short resumes of the presentations at the 1990 Fuel Cell Seminar held November 25-28, 1990 in Phoenix, Arizona. Contained herein are 134 short descriptions organized into topic areas entitled An Environmental Overview, Transportation Applications, Technology Advancements for Molten Carbonate Fuel Cells, Technology Advancements for Solid Fuel Cells, Component Technologies and Systems Analysis, Stationary Power Applications, Marine and Space Applications, Tech… more
Date: December 31, 1990
Partner: UNT Libraries Government Documents Department
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A 2D electrostatic PIC code for the Mark III Hypercube

Description: We have implemented a 2D electrostastic plasma particle in cell (PIC) simulation code on the Caltech/JPL Mark IIIfp Hypercube. The code simulates plasma effects by evolving in time the trajectories of thousands to millions of charged particles subject to their self-consistent fields. Each particle`s position and velocity is advanced in time using a leap frog method for integrating Newton`s equations of motion in electric and magnetic fields. The electric field due to these moving charged partic… more
Date: December 31, 1990
Creator: Ferraro, R. D.; Liewer, P. C. & Decyk, V. K.
Partner: UNT Libraries Government Documents Department
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A 3D Particle Simulation Code for Heavy Ion Fusion Accelerator Studies

Description: We describe WARP, a new particle-in-cell code being developed and optimized for ion beam studies in true geometry. We seek to model transport around bends, axial compression with strong focusing, multiple beamlet interaction, and other inherently 3d processes that affect emittance growth. Constraints imposed by memory and running time are severe. Thus, we employ only two 3d field arrays ({rho} and {phi}), and difference {phi} directly on each particle to get E, rather than interpolating E from … more
Date: June 8, 1990
Creator: Friedman, A.; Bangerter, R. O.; Callahan, D. A.; Grote, D. P.; Langdon, A. B. & Haber, I.
Partner: UNT Libraries Government Documents Department
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3D Particle Simulation of Beams Using the Warp Code: Transport Around Bends

Description: WARP is a discrete-particle simulation program which was developed for studies of space charge dominated ion beams. It combines features of an accelerator code and a particle-in-cell plasma simulation. The code architecture, and techniques employed to enhance efficiency, are briefly described. Current applications are reviewed. In this paper we emphasize the physics of transport of three-dimensional beams around bends. We present a simple bent-beam PIC algorithm. Using this model, we have follo… more
Date: November 30, 1990
Creator: Friedman, A.; Grote, D. P.; Callahan, D. A.; Langdon, A. B. & Haber, I.
Partner: UNT Libraries Government Documents Department
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3D simulations of axially confined heavy ion beams in round and square pipes

Description: We have been using the 3d PIC code WARP6 to model the behavior of beams in a heavy ion induction accelerator; such linacs are candidates for an ICF driver. Improvements have been added to the code to model an axially confined beam using comoving axial electric fields to simulate the confining ears'' applied to the accelerating pulses in a real system. We have also added a facility for modeling a beam in a round pipe, applying a capacity matrix to each axial Fourier mode in turn. These additions… more
Date: November 30, 1990
Creator: Grote, D. P.; Friedman, A. (Lawrence Livermore National Lab., CA (USA)) & Haber, I. (Naval Research Lab., Washington, DC (USA))
Partner: UNT Libraries Government Documents Department
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The A dependence of dilepton production

Description: The discovery in 1982, by the EMC group, that the structure function F{sub 2}(x) per nucleon is different in iron than deuterium was the first evidence that the structure of the nucleon might be altered in nuclei. Much more extensive and precise and data have been taken since the original discovery. This body of data is now quite consistent and many of the features of the original EMC effect'' remain intact. There have been a variety of theoretical explanations of the data, but none are totally… more
Date: January 1, 1990
Creator: Garvey, Gerald T.
Partner: UNT Libraries Government Documents Department
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A1-U fuel foaming/recriticality considerations for production reactor core-melt accidents

Description: Severe accident studies for the Savannah River production reactors indicate that if coherent fuel melting and relocation occur in the absence of target melting, in-vessel recriticality may be achieved. In this paper, fuel-melt/target interaction potential is assessed, where fission gas-induced fuel foaming and melt attach on target material are evaluated and compared with available data. Models are developed to characterize foams for irradiated Al-based fuel. Predictions indicate transient foam… more
Date: January 1, 1990
Creator: Cronenberg, A.W. (Engineering Science and Analysis, Albuquerque, NM (USA)); Hyder, M.L. & Ellison, P.G. (Westinghouse Savannah River Co., Aiken, SC (USA))
Partner: UNT Libraries Government Documents Department
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Abiotic immobilization/detoxification of recalcitrant organics

Description: In contrast to many remedial techniques that simply transfer hazardous wastes from one part of the environment to another (e.g., off-site landfilling), in situ restoration may offer a safe and cost-effective solution through transformation (to less hazardous products) or destruction of recalcitrant organics. Currently, the US Environmental Protection Agency and US Department of Energy are encouraging research that addresses the development of innovative alternatives for hazardous-waste control.… more
Date: November 1, 1990
Creator: Whelan, G. & Sims, R. C.
Partner: UNT Libraries Government Documents Department
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ABRAC: A microcomputer-based Fortran code for multi-cyle burnup

Description: Pressurized-water reactors have reactor physics and fuel management characteristics which are very amenable to simplified analysis. Given models which account for the dominant features of core and fuel performance, it is possible to rapidly perform relatively accurate scoping studies of many years of reactor operation in just a few hours on a modern (386-class) microcomputer. Models are described for burnup-dependent cross-section generation, for burnup of fuel under irradiation, and for comput… more
Date: January 1, 1990
Creator: Olson, A. P.
Partner: UNT Libraries Government Documents Department
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[Abstracts from US Department of Energy contractors` meeting]

Description: A series of abstracts is given on the subjects of theory for multiply charged ions and low- and high-energy collisions involving multiply charged ions. 23 refs.
Date: 1990~
Creator: Richard, P.
Partner: UNT Libraries Government Documents Department
open access

Accelerating and storing polarized hadron beams

Description: Polarization hadron experiments at high energies continue to generate surprises. Many questions remain unanswered or unanswerable within the frame work of QCD. These include such basic questions as to why at high energies the polarization analyzing power in pp elastic scattering remains high, why hyperons are produced with high polarizations etc. It is, therefore, interesting to investigate the possibilities of accelerating and storing polarized beams in high energy colliders. On the technical … more
Date: October 1, 1990
Creator: Teng, L.C.
Partner: UNT Libraries Government Documents Department
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Acceleration of compact toruses and fusion applications

Description: The Compact Torus (Spheromak-type) is a near ideal plasma confinement configuration for acceleration. The fields are mostly generated by internal plasma currents, plasma confinement is toroidal, and the compact torus exhibits resiliency and stability in virtue of the ``rugged`` helicity invariant. Based on these considerations we are developing a coaxial rail-gun type Compact Torus Accelerator (CTA). In the CTA, the CT ring is formed between coaxial electrodes using a magnetized Marshall gun, i… more
Date: October 11, 1990
Creator: Hartman, C. W.; Eddleman, J. L.; Hammer, J. H.; Logan, B. G.; McLean, H. S. & Molvik, A. W.
Partner: UNT Libraries Government Documents Department
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