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Brookhaven highlights for fiscal year 1991, October 1, 1990--September 30, 1991

Description: This report highlights Brookhaven National Laboratory's activities for fiscal year 1991. Topics from the four research divisions: Computing and Communications, Instrumentation, Reactors, and Safety and Environmental Protection are presented. The research programs at Brookhaven are diverse, as is reflected by the nine different scientific departments: Accelerator Development, Alternating Gradient Synchrotron, Applied Science, Biology, Chemistry, Medical, National Synchrotron Light Source, Nuclea… more
Date: January 1, 1991
Creator: Rowe, M.S.; Cohen, A.; Greenberg, D.; Seubert, L. & Kuper, J.B.H.
Partner: UNT Libraries Government Documents Department
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Impulsive ion acceleration in earth's outer magnetosphere

Description: Considerable observational evidence is found that ions are accelerated to high energies in the outer magnetosphere during geomagnetic disturbances. The acceleration often appears to be quite impulsive causing temporally brief (10's of seconds), very intense bursts of ions in the distant plasma sheet as well as in the near-tail region. These ion bursts extend in energy from 10's of keV to over 1 MeV and are closely associated with substorm expansive phase onsets. Although the very energetic ions… more
Date: January 1, 1985
Creator: Baker, D.N. & Belian, R.D.
Partner: UNT Libraries Government Documents Department
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Institutional research and development, FY 1987

Description: The Institutional Research and Development program at Lawrence Livermore National Laboratory fosters exploratory work to advance science and technology, disciplinary research to develop innovative solutions to problems in various scientific fields, and long-term interdisciplinary research in support of defense and energy missions. This annual report describes research funded under this program for FY87. (DWL)
Date: January 1, 1987
Creator: Struble, G. L.; Lawler, G. M.; Crawford, R. B.; Kirvel, R. D.; Peck, T. M.; Prono, J. K. et al.
Partner: UNT Libraries Government Documents Department
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Relation between finite element methods and nodal methods in transport theory

Description: This paper examines the relationship between nodal methods and finite-element methods for solving the discrete-ordinates form of the transport equation in x-y geometry. Specifically, we will examine the relation of three finite-element schemes to the linear-linear (LL) and linear-nodal (LN) nodal schemes. The three finite-element schemes are the linear-continuous-diamond-difference (DD) scheme, the linear-discontinuous (LD) scheme, and the quadratic-discontinuous (QD) scheme. A brief derivation… more
Date: January 1, 1985
Creator: Walters, W. F.
Partner: UNT Libraries Government Documents Department
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Conductor qualification tests for the 30-MJ Bonneville Power Administration SMES coil

Description: The 30-MJ energy storage coil for the Bonneville Power Administration requires a low-loss, cryostable conductor that is able to carry 4.9 kA in a field of 2.8 T and will maintain its properties over 10/sup 8/ partial discharge cycles. The multi-level cable which satisfies these requirements has been extensively tested at various stages in its development and in its final form. Tests have been performed to determine the effect of manufacturing options on ac losses, low temperature electrical res… more
Date: January 1, 1980
Creator: Schermer, R. I.; Boenig, H. J.; Henke, M.; Turner, R. D. & Schramm, R.
Partner: UNT Libraries Government Documents Department
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Estimates of SASE power in the short wavelength region

Description: Given a sufficiently bright electron beam, the self-amplified-spontaneous emission (SASE) can provide gigawatts of short wavelength coherent radiation. The advantages of SASE approach are that is requires neither optical cavity nor an imput seed laser. In this note, we estimate the peak power performance of SASE for wavelengths shorter than 1000 {Angstrom}. At each wavelength, we calculate the saturated power from a uniform parameter undulator and the enhanced power from a tapered undulator. Th… more
Date: March 1, 1992
Creator: Kim, Kwang-Je.
Partner: UNT Libraries Government Documents Department
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Conceptual design of a superconducting magnet coil for the large coil program. [Flat-wound NbTi coils]

Description: A conceptual design for a toroidal field (TF) coil for a six coil test array has been developed. The electromagnetic, cryogenic, structural, manufacturing, quality assurance and verification testing requirements have been analyzed. The bore is oval shaped and is 2.35 meters horizontally and 3.35 meters vertically. The coil is designed to operate at 8T peak field at rated current of 10450 amperes when the other 5 coils in the toroidal array are at 80% rated current. Using-flat-wound NbTi conduct… more
Date: January 1, 1977
Creator: Quay, R.; Bryant, R. W.; Koenig, R. F.; Ferrante, J. J.; Linkinhoker, C. L.; Donato, J. W. et al.
Partner: UNT Libraries Government Documents Department
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Pseudorapidity distributions and correlations in central sup 16 O interactions at 200 A GeV

Description: Whether or not adequate energy densities for a transition to the Quark-Gluon Plasma (QGP) phase are possible in {sup 16}O and {sup 32}S induced reactions is still an open question. Before unambiguous signals can be identified it is necessary to understand the background upon which the expected QGP signatures can be sought. An important aim of early experiments in this new energy density regime is thus to understand the process of hadronization in a nuclear environment. In any discussion of high… more
Date: January 1, 1988
Creator: Wilkes, R. J.
Partner: UNT Libraries Government Documents Department
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Efficiencies of gas neutralizers for multi-MeV beams of light negative ions

Description: Measurements are reported of the neutral and charged particle fractions produced by running beams of Li/sup -/, C/sup -/, O/sup -/, and Si/sup -/ at energies up to 7 MeV through gas cells of N/sub 2/, Ar, or CO/sub 2/. We discuss the implications of these measurements for the design of neutralizers to produce high energy light atom beams for heating or current drive in tokamaks.
Date: November 1, 1981
Creator: Grisham, L. R.; Post, D. E.; Johnson, B. M.; Jones, K. W.; Barette, J.; Kruse, T. H. et al.
Partner: UNT Libraries Government Documents Department
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Cross Sections for X-Ray Photoelectron-Induced Desorption of Hydrogen Ions From Metal Surfaces

Description: We have measured the cross sections for x-ray photoelectron-induced desorption of hydrogen ions from beryllium, carbon, aluminum, tantalum, and gold surfaces. This report describes the results of the cross-section measurements, and discusses a time-of-flight technique that allows the determination of ionic-desorption cross sections as small as 10/sup -25/ cm/sup 2/ per photoelectron. 19 refs., 7 figs.
Date: September 20, 1985
Creator: Kinney, J. H.; Siekhaus, W. J. & Anderson, R. A.
Partner: UNT Libraries Government Documents Department
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Sources of polarized ions and atoms

Description: In this presentation we discuss methods of producing large quantities of polarized atoms and ions (Stern-Gerlach separation, optical pumping, and spin-exchange) as well as experimental methods of measuring the degree of polarization of atomic systems. The usefulness of polarized atoms in probing the microscopic magnetic surface properties of materials will also be discussed. 39 refs., 5 figs., 2 tabs.
Date: January 1, 1988
Creator: Cornelius, W.D.
Partner: UNT Libraries Government Documents Department
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Parametric study of the stability margins of cable-in-conduit superconductors: experiment

Description: In a previous experiment on the stability of cable-in-conduit superconductors, we sometimes observed multivalued stability margins, which we attributed to strong heating-induced transient flows. We proposed a schematic theory from which we derived a scaling relation for the limiting current below which the stability margin is always singlevalued. Measurements at different magnetic fields are used to test the scaling with critical temperature and resistivity. We also examine the scaling with hea… more
Date: January 1, 1980
Creator: Lue, J. W. & Miller, J. R.
Partner: UNT Libraries Government Documents Department
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Toroidal plasma equilibrium with gravity

Description: Toroidal magnetic field configuration in a gravitational field is calculated both from a simple force-balance and from the calculation using magnetic surfaces. The configuration is found which is positionally stable in a star. The vibrational frequency near the equilibrium point is proportional to the hydrostatic frequency of a star multiplied by the ratio (W/sub B//W/sub M/)/sup 1/2/ where W/sub B/ is the magnetic field energy density, and W/sub M/ is the material pressure at the equilibrium p… more
Date: September 1, 1980
Creator: Yoshikawa, S.
Partner: UNT Libraries Government Documents Department
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Photophoresis and the scattering of electromagnetic radiation

Description: Electron-microscope photographs of soot lend support to the picture in which a soot particle is modeled as a collection of chains of small carbon spheres. The soot particle itself is typically considerably larger than the small carbon spheres making up the chains. Thus the soot particles might have a size approx.0.1 - 1 ..mu..m while the small carbon spheres might have a size approx.0.03 ..mu..m in typical situations. Further, measurements of the density of soot yield values much less than that… more
Date: September 1, 1985
Creator: Ipser, J.R.
Partner: UNT Libraries Government Documents Department
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The solar flare of 18 August 1979: Incoherent scatter radar data and photochemical model comparisons

Description: Measurements of electron density at seven D-region altidues were made with the Arecibo radar during a Class-X solar flare on 18 August 1979. Measurements of solar x-ray fluxes during the same period were available from the GOES-2 satellite (0.5 to 4 /angstrom/ and 1 to 8 /angstrom/) and from ISEE-3 (in four bands between 26 and 400 keV). From the x-ray flux data we computed ionization rates in the D-region and the associated chemical changes, using a coupled atmospheric chemistry and diffusion … more
Date: April 1, 1988
Creator: Zinn, J.; Sutherland, C. D.; Fenimore, E. E. & Ganguly, S.
Partner: UNT Libraries Government Documents Department
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TPC magnet cryogenic system

Description: The Time Projection Chamber (TPC) magnet at LBL and its compensation solenoids are adiabatically stable superconducting solenoid magnets. The cryogenic system developed for the TPC magnet is discussed. This system uses forced two-phase tubular cooling with the two cryogens in the system. The liquid helium and liquid nitrogen are delivered through the cooled load by forced tubular flow. The only reservoirs of liquid cryogen exist in the control dewar (for liquid helium) and the conditioner dewar… more
Date: March 1, 1980
Creator: Green, M.A.; Burns, W.A.; Taylor, J.D. & Van Slyke, H.W.
Partner: UNT Libraries Government Documents Department
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Fractional charge search

Description: A device to search for fractional charge in matter is described. The sample is coupled to a low-noise amplifier by a periodically varying capacitor and the resulting signal is synchronously detected. The varying capacitor is constructed as a rapidly spinning wheel. Samples of any material in volumes of up to 0.05 ml may be searched in less than an hour.
Date: June 1, 1982
Creator: Innes, W.; Klein, S.; Perl, M. & Price, J.C.
Partner: UNT Libraries Government Documents Department
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Products from cosmic-ray interactions in extraterrestrial matter: What they tell us about radiation backgrounds in space

Description: The nuclides and the heavy-nuclei ''tracks'' made by the interactions of solar and galactic cosmic-ray particles with meteorites, lunar samples, and the Earth have been extensively studied, simulated, and modelled. Most research involves the use of these cosmogenic products to study the history of the ''targets'' or of the cosmic rays. However, much work has also been done in understanding these interactions and in predicting their rates as a function of the target's size and shape and of the l… more
Date: January 1, 1987
Creator: Reedy, R. C.
Partner: UNT Libraries Government Documents Department
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A cryogenic system design for the international thermonuclear experimental reactor (ITER)

Description: A conceptual design for ITER was completed last year. The author developed a suitable cryogenic system for ITER as part of this conceptual design effort. An overview of the design is reported. Emphasis is on the fact that cryogenics is a mature science, and a system supporting ITER needs can be made from time-proven components without loss of efficiency or reliability. Because of the large size of the ITER cryogenic system, large numbers of compressors and expanders must be used. Very high reli… more
Date: September 25, 1991
Creator: Slack, D.S.
Partner: UNT Libraries Government Documents Department
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Fermi molecular dynamics

Description: classical many body models supplemented by repulsive momentum-dependent potentials to simulate the Pauli and Heisenberg principles have been use with some success for nuclear and atomic bound state and collision problems. They are capable of describing mean ground state properties, hydrodynamics, shocks (if warranted by the physics), viscosity, correlations, clustering, fragmentation, etc. We have become interested in the Feldmeier Gaussian packet formulation since it is based on a variational … more
Date: January 1, 1991
Creator: Wilets, L. & Beck, W.
Partner: UNT Libraries Government Documents Department
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Structure of NH/sub 3/ on Ni(111)

Description: In a recent study of the adsorption of NH/sub 3/ on NI(111) at T approx. 190 K using angle resolved UPS, it was concluded that NH/sub 3/ is molecularly adsorbed, and is bonded to the surface via the N atom with the H atoms oriented away from the surface. To study the bonding configuration using a direct and independent technique, we have examined NH/sub 3/ on Ni(111) using the electron stimulated desorption ion angular distribution (ESDIAD) method, coupled with temperature programmed desorption… more
Date: January 1, 1980
Creator: Madey, T. E.; Houston, J. E.; Seabury, C. W. & Rhodin, T. N.
Partner: UNT Libraries Government Documents Department
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