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2-D emittance equation with acceleration and compression

Description: Since both acceleration and compression are required for an Inertial Fusion Driver, the understanding of their effect on the beam quality, emittance, is important. This report attempts to generalize the usual emittance formula for the drifting beam to include these effects. The derivation of the 2-D emittance equation is carried out and a comparison with the particle code results is given. The 2-D emittance at a given axial location is reasonable to consider for a long beam, particularly with v… more
Date: October 1, 1988
Creator: Hahn, K. D. & Smith, L.
Item Type: Refine your search to only Report
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2-D Eulerian hydrodynamics with fluid interfaces, self-gravity and rotation

Description: 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 study… more
Date: January 1, 1982
Creator: Norman, M.L. & Winkler, K.H.A.
Item Type: Refine your search to only Article
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2-D skin-current toroidal-MHD-equilibrium code

Description: A two-dimensional, toroidal, ideal MHD skin-current equilibrium computer code is described. The code is suitable for interactive implementation on a minicomptuer. Some examples of the use of the code for design and interpretation of toroidal cusp experiments are presented.
Date: September 1, 1982
Creator: Feinberg, B.; Niland, R. A.; Coonrod, J. & Levine, M. A.
Item Type: Refine your search to only Report
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2-D time evolution of T/sub e/ during sawtooth crash based on fast ECE (electron cyclotron emission) measurements on TFTR

Description: Electron cyclotron emission measurements taken at 20 locations in the horizontal midplane during a sawtooth crash have been analysed based on the assumption of fast rigid rotation of the plasma. Due to this fast rotation (approx.100..mu..sec), which remains fairly constant throughout the sawtooth crash, we have been able to make time-to-space reconstructions of half the poloidal plane using points which are separated in time by not more than 40..mu..sec. The existence of a temperature flattenin… more
Date: December 1, 1988
Creator: Kuo-Petravic, G.
Item Type: Refine your search to only Report
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S = -2 dibaryons and hypernuclei

Description: 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… more
Date: January 1, 1982
Creator: Dover, C.B.
Item Type: Refine your search to only Article
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2-Dimensional studies of the disk-and-washer and side-coupled resonant cavity structures

Description: The work done consists of three parts: optimizing the disk-and-washer (DAW) structure at ..beta.. = 0.5662 corresponding to E = 200 MeV; comparing the DAW structure with the side-coupled (SCS) structure at various values of beta, ranging from ..beta.. = 0.4569 and E = 116 MeV to ..beta.. = 0.7131 and E = 400 MeV; and re-optimizing the DAW structure at ..beta.. = 0.7131. 4 refs., 51 figs., 41 tabs.
Date: December 1, 1987
Creator: Larry, L.D. Jr.
Item Type: Refine your search to only Report
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N = 2 Maxwell-Einstein Supergravity Theories: Their Compact and Non-Compact Gaugings and Jordan Algebras

Description: In this talk we give a review of our work on the construction and classification of N = 2 Maxwell-Einstein Supergravity theories (MESGT), study of the underlying algebraical and geometrical structure of these theories, and their compact and non-compact gaugings. We begin by summarizing our construction of the N = 2 MESGT's in five dimensions and give a geometrical interpretation to various scalar dependent quantities in the Lagrangian, based on the constraiants implied by supersymmetry. This is… more
Date: January 1, 1985
Creator: Guenaydin, M.; Sierra, G. & Townsend, P.K.
Item Type: Refine your search to only Article
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A 2-MeV microwave thermionic gun

Description: A high-gradient, S-band microwave gun with a thermionic cathode is being developed in a collaborative effort by AET, Varian, and SSRL. A prototype design using an upgraded Varian dispenser cathode mounted with thermal isolation directly in the first half-cell of a 1-1/2 cell, side-coupled, standing-wave cavity has been fabricated and is being tested. Optimization of the cavity shape and beam formation was done using SUPERFISH, MASK, and PARMELA. An overview of design details, as well as the sta… more
Date: August 1, 1989
Creator: Tanabe, E.; Borland, M.; Green, M. C.; Miller, R. H.; Nelson, L. V.; Weaver, J. N. et al.
Item Type: Refine your search to only Article
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A 2-MV multi-beam injector for heavy ion fusion

Description: Construction of a sixteen beam (0.5 A per beam) injector for use in scaled heavy ion fusion experiments is underway at LBL. The machine was designed and partially constructed at LANL. The injector is designed to use carbon arc sources which will provide 25 mA/cm/sup 2/ of extractable current density. The plasma from the arcs is confined electrostatically from drifting into the ion gun before firing the extraction pulse. The acceleration column consists of a set of aperture lenses which both tra… more
Date: June 1, 1988
Creator: Rutkowski, H. L.; Faltens, A.; Vanecek, D.; Pike, C.; Humphries, S., Jr. & Meyer, E. A.
Item Type: Refine your search to only Article
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2, Pulse-mode expansions and refractive indices in plane-wave propagation

Description: This memo presents basic background theory for treating simultaneous propagation of electromagnetic pulses of various colors, directed along a common ray, through a molecular vapor. The memo discusses some techniques for expanding the positive frequency part of the transverse electric field into pulse modes, characterized by carrier frequencies within a modulated envelope. We discuss, in the approximation of plane waves with slowly varying envelopes, a set of uncoupled envelope equations in whi… more
Date: June 20, 1987
Creator: Shore, B. W.; Sacks, R.; Karr, T.; Morris, J. & Paisner, J. A.
Item Type: Refine your search to only Report
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3. 6 simplified methods for design

Description: Simplified design analysis methods for elevated temperature construction are classified and reviewed. Because the major impetus for developing elevated temperature design methodology during the past ten years has been the LMFBR program, considerable emphasis is placed upon results from this source. The operating characteristics of the LMFBR are such that cycles of severe transient thermal stresses can be interspersed with normal elevated temperature operational periods of significant duration, … more
Date: January 1, 1981
Creator: Nickell, R.E. & Yahr, G.T.
Item Type: Refine your search to only Article
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3-10 keV and 0. 1- to 2-MeV observations of four gamma-ray bursts

Description: Four catalogued ..gamma..-ray bursts that occurred between 79/3/7 and 79/7/31 have been observed over the 3 to 10 keV range by a joint NRL/Los Alamos experiment on the Air Force P78-1 satellite. The bursts were also well observed by members of the interplanetary network. In this paper we present hardness ratios, x-ray/..gamma..-ray luminosity ratios, and time histories. The most significant results presented herein can be summarized as follows: (1) gamma-ray bursters can emit fairly strongly at… more
Date: January 1, 1983
Creator: Laros, J. G.; Evans, W. D.; Fenimore, E. E.; Klebesadel, R. W.; Shulman, S. & Fritz, G.
Item Type: Refine your search to only Article
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3-body final states in peripheral heavy-ion collisions: nuclear clustering structure and projectile excitation revisited

Description: Even though peripheral heavy-ion collisions are less violent than their central counterparts, the large energy exchange between the reactants often leaves the primary products in excited particle-unstable states whose subsequent decay leads to 3 or more nuclei emerging in the final exit channel. These post-reaction, predominantly sequential de-excitation processes can sometimes provide interesting structural information about the parent nuclei. In fact, provided these processes are well underst… more
Date: February 1, 1986
Creator: Chan, Y.; Chavez, E.; Gazes, S.B.; Kamermans, R.; Schmidt, H.R.; Siwek-Wilczynska, J. et al.
Item Type: Refine your search to only Article
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3-D Analysis on Arbitrarily-Shaped Icrf Antennas and Faraday Shields

Description: Cavity antennas with Faraday shields are proposed to couple ion cyclotron radio frequency power for heating fusion plasmas. This application requires small, high-power, low-frequency antennas. The results are presented of a theoretical study of the ICRF antennas being developed for this purpose at the Radio Frequency Test Facility (RFTF). The objectives of this work are to optimize experimental designs and to confirm test results. (MOW)
Date: January 1, 1986
Creator: Chen, G. L.; Whealton, J. H.; Baity, F. W.; Hoffman, D. J. & Owens, T. L.
Item Type: Refine your search to only Article
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3-D computer simulations of EM field sin the APS vacuum chamber. Part 2: Time-domain analysis

Description: Our simulations suggest that the strong peak around 4 GHz in the narrow gap observed in the measurements is generated by TE modes. Therefore, one should not worry about this peak insofar as the coupling impedance is concerned. On the other hand, some discrepancies between our simulations and the measurements are noticed and remain to be resolved.
Date: January 20, 1989
Creator: Chou, W.
Item Type: Refine your search to only Report
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A 3-D dynamical/chemical GCM for simulating the anthropogenical effects on ozone

Description: In spite of the significantly increased attention atmospheric ozone has received over the last two decades or so, a fully quantitative understanding of the three-dimensional ozone structure remains unavailable. In the past, one-dimensional (vertical column) models have provided most of the quantitative simulations of atmospheric chemical systems, because these models can treat large ensembles of chemical process economically. More recently, two-dimensional (meridional cross section) models have… more
Date: January 1, 1989
Creator: Kao, C. Y. J.; Glatzmaier, G. A.; Malone, R. C. & Turco, R. P.
Item Type: Refine your search to only Article
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3-D heat transfer computer calculations of the performance of the IAEA's air-bath calorimeters

Description: A three dimensional (3-D) heat transfer computer code was developed to study and optimize the design parameters and to better understand the performance characteristics of the IAEA's air-bath calorimeters. The computer model accounts for heat conduction and radiation in the complex materials of the calorimeter and for heat convection and radiation at its outer surface. The temperature servo controller is modelled as an integral part of the heat balance equations in the system. The model predict… more
Date: January 1, 1989
Creator: Elias, E.; Kaizermann, S.; Perry, R. B. & Fiarman, S.
Item Type: Refine your search to only Article
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3-D hybrid PIC code to model the tilt mode in FRCs

Description: The results from QN3D are presented. QN3D is a 3-dimensional hybrid particle-in-cell code designed to run efficiently on the Cray-2 Multiprocessor. The chief application has been to the tilt mode instability in FRCs. QN3D accepts as input, the magnetic field, the ion particle density and the ion temperature on a two-dimensional r-z grid. These quantities are interpolated to the rest of the cartesian grid under the assumption of azimuthal symmetry. The particles are initialized with random numbe… more
Date: June 1, 1987
Creator: Horowitz, E. J. & Shumaker, D. E.
Item Type: Refine your search to only Article
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3-D magnetic field calculations for wiggglers using MAGNUS-3D

Description: The recent but steady trend toward increased magnetic and geometric complexity in the design of wigglers and undulators, of which tapered wigglers, hybrid structures, laced electromagnetic wigglers, magnetic cladding, twisters and magic structures are examples, has caused a need for reliable 3-D computer models and a better understanding of the behavior of magnetic systems in three dimensions. The capabilities of the MAGNUS-3D Group of Programs are ideally suited to solve this class of problems… more
Date: January 1, 1988
Creator: Pissanetzky, S. & Tompkins, P.
Item Type: Refine your search to only Article
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A 3-D measurement system using object-oriented FORTH

Description: Discussed is a system for storing 3-D measurements of points that relates the coordinate system of the measurement device to the global coordinate system. The program described here used object-oriented FORTH to store the measured points as sons of the measuring device location. Conversion of local coordinates to absolute coordinates is performed by passing messages to the point objects. Modifications to the object-oriented FORTH system are also described. 1 ref.
Date: January 1, 1989
Creator: Butterfield, K.B.
Item Type: Refine your search to only Article
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3-D Nonlinear Calculations of Resistive Tearing Modes

Description: Recent numerical calculations of the evolution of resistive tearing modes have been central to the understanding of magnetohydrodynamic activity and disruptions in tokamaks. The nonlinear, 3-D, initial-value computer code RSF has provided many of these results. This code assumes cylindrical geometry with a Fourier series representation in the two periodic coordinates and a finite-difference representation in the radial direction. This choice makes RSF considerably more accurate and efficient th… more
Date: March 1, 1981
Creator: Hicks, H. R.; Holmes, J. A.; Lee, D. K.; Carreras, B. & Waddell, B. V.
Item Type: Refine your search to only Report
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3-D numerical analysis of a high-gain free-electron laser

Description: We present a novel approach to the 3-dimensional high-gain free- electron laser amplifier problem. The method allows us to write the laser field as an integral equation which can be efficiently and accurately evaluated on a small computer. The model is general enough to allow the inclusion of various initial electron beam distributions to study the gain reduction mechanism and its dependence on the physical parameters. 16 refs., 8 figs., 1 tab.
Date: October 19, 1988
Creator: Gallardo, J.C.
Item Type: Refine your search to only Report
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3-D resistive MHD calculations for tokamak plasmas: beyond the simple reduced set of equations

Description: Numerical studies of the resistive stability of tokamak plasmas in cylindrical geometry have been performed using: (1) the full set of resistive Magnetohydrodynamic (MHD) equations and (2) an extended version of the reduced set of resistive MHD equations including diamagnetic and electron temperature effects. In particular, the nonlinear interaction of tearing modes of many helicities has been investigated. The numerical results confirm many of the features uncovered previously using the simple… more
Date: January 1, 1983
Creator: Carreras, B. A.; Garcia, L.; Hender, T. C.; Hicks, H. R.; Holmes, J. A.; Lynch, V. E. et al.
Item Type: Refine your search to only Article
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3-D solution of flow in an infinite square array of circular tubes by using boundary-fitted coordinate system

Description: 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 over… more
Date: January 1, 1982
Creator: Chen, B. C. J.; Chien, T. H.; Sha, W. T. & Kim, J. H.
Item Type: Refine your search to only Article
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