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1-2 GeV synchrotron radiation facility at Lawrence Berkeley Laboratory

Description: The Advanced Light Source (ALS), a dedicated synchrotron radiation facility optimized to generate soft x-ray and vacuum ultraviole (XUV) light using magnetic insertion devices, was proposed by the Lawrence Berkeley Laboratory in 1982. It consists of a 1.3-GeV injection system, an electron storage ring optimized at 1.3 GeV (with the capability of 1.9-GeV operation), and a number of photon beamlines emanating from twelve 6-meter-long straight sections, as shown in Fig. 1. In addition, 24 bending-… more
Date: October 1, 1985
Creator: Berkner, K.H.
open access

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.
open access

6. 4 Tesla dipole magnet for the SSC

Description: A design is presented for a dipole magnet suitable for the proposed SSC facility. Test results are given for model magnets of this design 1 m long and 4.5 m long. Flattened wedge-shaped cables (''keystoned'') are used in a graded, two-layer ''cos theta'' configuration with three wedges to provide sufficient field uniformity and mechanical rigidity. Stainless steel collars 15 mm wide, fastened with rectangular keys, provide structural support, and there is a ''cold'' iron flux return. The outer-… more
Date: May 1, 1985
Creator: Taylor, C.E.; Caspi, S.; Gilbert, W.; Meuser, R.; Mirk, K.; Peters, C. et al.
open access

6. 4 tesla dipole magnet for the SSC. Revision

Description: A design is presented for a dipole magnet suitable for the proposed SSC facility. Test results are given for model magnets of this design 1 m long and 4.5 m long. Flattened wedge-shaped cables (''keystoned'') are used in a graded, two-layer ''cos theta'' configuration with three wedges to provide sufficient field uniformity and mechanical rigidity. Stainless steel collars 15 mm in radial depth, fastened with rectangular keys, provide structural support, and there is a ''cold'' iron flux return.… more
Date: August 1, 1985
Creator: Taylor, C.E.; Caspi, S.; Gilbert, W.; Hassenzahl, W.; Meuser, R.; Mirk, K. et al.
open access

10-MHz high-voltage modulator with pulse-width and repetition-rate agility

Description: Requirements for control and rapid switching of the proton beam at the Los Alamos Meson Physics Facility (LAMPF) are continually revised to support accelerator upgrades and modifications. A recent upgrade required the development of a 10-MHz high-voltage modulator for an electrostatic kicker with real-time control of pulse width and repetition rate over a range of four decades. The modulator must be capable of producing a voltage pulse across a capacitive load with a rise time of less than or e… more
Date: January 1, 1985
Creator: Krausse, G.J.
open access

14 MeV neutron work at the Lawrence Livermore National Laboratory

Description: The 14 MeV neutron work at Lawrence Livermore National Laboratory (LLNL) covers two main areas of interest to this Symposium: (1) measurements and calculations of differential cross sections; and (2) integral measurements of the neutron and gamma emission spectra. In both areas a large number of materials have been studied, spanning a wide mass range (6 < A < 239), of interest to fusion and hybrid reactors. In this presentation a brief description of the experimental techniques and calculationa… more
Date: July 1, 1985
Creator: Hansen, L. F.
open access

20 keV undulators for a 6-GeV storage ring

Description: The main goal of the future 6-GeV electron storage ring is to provide 20-keV fundamental harmonic radiations from insertion devices. Parameter restrictions of REC-vanadium permendur hybrid undulators have been examined. The critical factor is the achievable minimum gap of the undulator. Variations of the spectral brilliance for different beam parameters are also shown. 6 refs., 5 figs.
Date: January 1, 1985
Creator: Kim, S. H. & Cho, Y.
open access

32-Bit computer for large memory applications on FASTBUS

Description: A FASTBUS based 32-bit computer is being built at Los Alamos National Laboratory for use in systems requiring large fast memory in the FASTBUS environment. A separate local execution bus allows data reduction to proceed concurrently with other FASTBUS operations. The computer, which can operate in either master or slave mode, includes the National Semiconductor NS32032 chip set with demand paged memory management, floating point slave processor, interrupt control unit, timers, and time-of-day c… more
Date: January 1, 1985
Creator: Blossom, J. M.; Hong, J. P. & Kellner, R. G.
open access

32-Bit FASTBUS computer

Description: Los Alamos National Laboratory is building a 32-bit FASTBUS computer using the NATIONAL SEMICONDUCTOR 32032 central processing unit (CPU) and containing 16 million bytes of memory. The board can act both as a FASTBUS master and as a FASTBUS slave. It contains a custom direct memory access (DMA) channel which can perform 80 million bytes per second block transfers across the FASTBUS.
Date: January 1, 1985
Creator: Blossom, J.M.; Hong, J.P. & Kellner, R.G.
open access

300-Element Silicon-Lithium Position-Sensitive Imaging Detector for Angiography

Description: Silicon lithium-drifted (Si(Li)) detectors 150 mm long, 10 mm wide and 5 mm thick with 300 individual elements have been fabricated as imaging detectors for noninvasive studies of human coronary arteries using 33 keV x-rays from a synchrotron radiation beamline. This detector is an extension of earlier work on 30 mm long devices with initially 30 and later 60 elements. The detector fabrication details are discussed highlighting problems in uniform lithium-ion compensation. The device structure … more
Date: October 1, 1985
Creator: Walton, J. T.; Sommer, H. A.; Thompson, A. C.; Hughes, E. B. & Zeman, H. D.
open access

1500-MeV fixed-field alternating-gradient synchrotron for a pulsed-spallation neutron source

Description: The first conceptual design of the FFAG for ASPUN was an 1100-MeV, 20-sector machine with an injection radius of 17.5 m and an extraction radius of 18.75 m. The conceptual design currently under study has a higher extraction energy, a larger average radius, but still has 20 sectors. The current interest in higher extraction energy is stimulated by calculations that indicate that the useful neutron production per incident proton is still increasing proportionally up to 1500 MeV. The larger radiu… more
Date: January 1, 1985
Creator: Kustom, R.L.; Khoe, T.K. & Crosbie, E.A.
open access

1982 THERMAL SHALLOW RESERVOIR TESTING

Description: An extensive study of the Thermal Shallow Reservoir at The Geysers was performed in 1982 to improve our understanding of the source and flow patterns of steam in the shallow anomaly and how they relate to the Thermal 4 blowout. This project included gathering and analyzing pressure transient, enthalpy, tracer and chemical data and developing a reservoir model that was consistent with this data. Following the pressure transient testing and analysis, a convection-plume with lateral-flow model was… more
Date: January 22, 1985
Creator: Mogen, P.; Pittinger, L. & Magers, M.
open access

2D ACAR momentum density study of the nature of the positron surface state on Al(100)

Description: The two-dimensional angular correlation of the 2..gamma.. annihilation radiation (2D ACAR) has been measured from an Al(100) surface bombarded by 200-eV positrons. After removing the contribution of fast para-positronium annihilation, the spectrum from positrons annihilating at the surface exhibits a nearly isotropic conical shape with a (7.1 +- 0.5) mrad FWHM. 5 refs., 6 figs.
Date: January 1, 1985
Creator: Berko, S.; Canter, K. F.; Lynn, K. G.; Mills, A. P.; Roellig, L. O. & West, R. N.
open access

3081/E processor and its on-line use

Description: The 3081/E is a second generation emulator of a mainframe IBM. One of it's applications will be to form part of the data acquisition system of the upgraded Mark II detector for data taking at the SLAC linear collider. Since the processor does not have direct connections to I/O devices a FASTBUS interface will be provided to allow communication with both SLAC Scanner Processors (which are responsible for the accumulation of data at a crate level) and the experiment's VAX 8600 mainframe. The 3081… more
Date: May 1, 1985
Creator: Rankin, P.; Bricaud, B.; Gravina, M.; Kunz, P. F.; Oxoby, G.; Trang, Q. et al.
open access

3D calculations of a fixed field alternating gradient synchrotron magnet

Description: A Spallation neutron source for materials science studies was designed at Argonne and required a fixed field alternating gradient (FFAG) synchrotron magnet. 3D electrostatic calculations were made to obtain the unsaturated magnet pole shape. This pole shape was refined using 3D magnetostatic calculations that included the steel permeability and coil geometry. Details of the calculations are given concerning such things as: size of the problem and how to split it up, the number and shape of the … more
Date: January 1, 1985
Creator: Lari, R.J.
open access

3lambda/4 post coupler for drift-tube linacs

Description: New permanent magnets for quadrupole focusing make possible smaller drift tubes in drift-tube linacs (DTLs), resulting in higher shunt impedance. However, ordinary post couplers cannot stabilize a DTL whose drift-tube-to-wall spacing exceeds one-quarter wavelength (lambda/4) by more than a few per cent for the accelerating mode frequency. We have built and tested post couplers that operate in the 3lambda/4 mode. These 3lambda/4 post couplers, when substituted for lambda/4 couplers, had similar … more
Date: January 1, 1985
Creator: Billen, J. H.; Garcia, J. A.; Potter, J. M. & Spalek, G.
open access

4X source

Description: Our Penning surface-plasma source (SPS) discharge chamber was enlarged 4X in two dimensions. To date, three pulsed discharge modes have been studied: two with noisy arc (greater than or equal to 20% H/sup -/ current fluctuations) and one with quiescent arc (less than or equal to 1% H/sup -/ current fluctuations). Lower arc magnetic field and higher H/sub 2/ gas flow allow switching from the noisy to the quiescent mode. The noisy modes yield up to 120 mA of 29-keV H/sup -/ beam; for 110 mA at 29… more
Date: January 1, 1985
Creator: Smith, H. Vernon, Jr.; Allison, Paul & Sherman, Joseph D.
open access

5cm, no iron SSC dipole 12m model cryostat thermal performance

Description: A 12 m long model of a 5 cm costheta dipole cryostat has been constructed and its thermal performance measured. The model utilized heat intercepted fiberglass reinforced plastic posts to support the 12 m long, 4.5 K cold mass and the 10 and 80 K thermal shields. A superinsulation blanket system utilizing aluminized polyester with fiberglass mat spacing material was developed and installed on the 10 and 80 K thermal shields. The heat gain to 4.5, 10 and 80 K was measured. We have compared the re… more
Date: September 1, 1985
Creator: Powers, R. J.; Gonczy, J. D.; Otavka, J.; Niemann, R. C.; Szymulanski, A. & Tague, J. L.
open access

5f-band narrowing in UX/sub 3/B compounds: evidence from resonant photoemission. [X = Ru or Rh]

Description: Resonant photoemission at the uranium 5d disorption edge has been used to determine the 5f emission in URu/sub 3/, URh/sub 3/, URu/sub 3/B, and URh/sub 3/B polycrystalline samples. The observed 5f band narrowing (from 2.0 to 1.5 eV as one goes from URu/sub 3/ to URu/sub 3/B, and from 2.8 to 1.1 eV for URh/sub 3/ and URh/sub 3/B respectively) is explained as due to a decrease in the f-d hybridization between uranium and rhodium (ruthenium) atoms.
Date: October 1985
Creator: Zolnierek, Z.; Arko, A. J. & Koelling, D. D.
open access

ABC's of pion charge exchange. [Absorption, blocking, and correlations]

Description: Calculations of pion single charge exchange using the PWIA and DWIA are presented. Emphasis is given to the effects of absorbtion and blocking. A microscopic calculation of the 0/sup 0/ excitation and low energy angular distribution is in excellent agreement with the data. A fixed nucleon multiple scattering calculation of the pion double charge exchange reaction is presented. Various valence neutron wave functions are used, and the contributions of different spatial orientations of the last tw… more
Date: 1985~
Creator: Gibbs, W.R.; Kaufmann, W.B. & Siegel, P.B.
open access

Abort kicker power supply systems at Fermilab

Description: Over the past several years, Fermilab has been operating with a single turn proton abort system in both the superconducting Tevatron and the conventional Main Ring. The abort kicker power supply for this system discharges a lumped capacitance into the inductive magnet load, causing the beam to enter the abort channel. The characteristics of this current waveform are defined by the requirements of the machine operation. The standard fixed target running mode calls for 12 booster batches of beam … more
Date: June 1, 1985
Creator: Krafczyk, G.; Dugan, G.; Harrison, M.; Koepke, K. & Tilles, E.
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