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open access

A 1.5 GeV compact light source with superconducting bending magnets

Description: This paper describes the design of a compact electron synchrotron light source for producing X-rays for medical imaging, protein crystallography, nano-machining and other uses up to 35 keV. The source will provide synchrotron light from six 6.9 tesla superconducting 60{degree} bending magnet stations. In addition the ring, contains conventional quadrupoles and sextupoles. The light source has a circumference of 26 meters, which permits it to be located in a variety of industrial and medical fac… more
Date: May 1995
Creator: Garren, A. A.; Cline, D. B.; Kolonko, J. J.; Green, M. A.; Johnson, D. E.; Leung, E. M. et al.
open access

A 2--4 nm Linac Coherent Light Source (LCLS) using the SLAC linac

Description: We describe the use of the SLAC linac to drive a unique, powerful. short wavelength Linac Coherent Light Source (LCLS). Operating as an FEL, lasing would be achieved in a single pass of a high peak current electron beam through a long undulator by self-amplified spontaneous emission (SASE). The main components are a high-brightness rf photocathode electron gun; pulse compressors; about 1/5 of the SLAC linac; and a long undulator with a FODO quadrupole focussing system. Using electrons below 8 G… more
Date: May 1, 1993
Creator: Winick, H.; Bane, K. & Boyce, R.
open access

2 {times} 2 TeV {mu}{sup +}{mu}{sup {minus}} collider: Lattice and accelerator-detector interface study

Description: The design for a high-luminosity {mu}{sup +}{mu}{sup {minus}} superconducting storage ring is presented based on first-pass calculations. Special attention is paid to two Iowa interaction regions (IR) whose optics are literally interlaced with the collider detectors. Various sources of backgrounds in IR are explored via realistic Monte Carlo simulations. An improved design of the collider lattice in the neighborhood of the interaction points (EP) is determined by the need to reduce significantl… more
Date: May 1, 1995
Creator: Gelfand, N. M. & Mokhov, N. V.
open access

A 10,000 A 1000 VDC solid state dump switch

Description: The superconducting magnet test program at Fermilab requires a switch, called a dump switch, rated 10,000 A, 1000 Vdc, which must be able to continuously carry rated current. A dump resistor rated 2 MJoules, is connected in parallel with the switch contacts and dissipates the stored energy from a magnet when the switch opens. The required switch opening time is 250 {mu}sec maximum after detection of a fault or a trip command. A successful switch can be constructed from six parallel inverter typ… more
Date: May 1, 1991
Creator: Visser, A.
open access

13 point video tape quality guidelines

Description: Until high definition television (ATV) arrives, in the U.S. we must still contend with the National Television Systems Committee (NTSC) video standard (or PAL or SECAM-depending on your country). NTSC, a 40-year old standard designed for transmission of color video camera images over a small bandwidth, is not well suited for the sharp, full-color images that todays computers are capable of producing. PAL and SECAM also suffers from many of NTSC`s problems, but to varying degrees. Video professi… more
Date: May 1, 1997
Creator: Gaunt, R.
open access

15.4% CuIn1-XGaXSe2-Based Photovoltaic Cells from Solution-Based Precursor Films

Description: We have fabricated 15.4%- and 12.4%-efficient CuIn1-XGaXSe2 (CIGS)-based photovoltaic devices from solution-based electrodeposition (ED) and electroless-deposition (EL) precursors. As-deposited precursors are Cu-rich CIGS. Additional In, Ga, and Se are added to the ED and EL precursor films by physical vapor deposition (PVD) to adjust the final film composition to CuIn1-XGaXSe2. The ED and EL device parameters are compared with those of a recent world record, an 18.8%-efficient PVD device. The … more
Date: May 25, 1999
Creator: Bhattacharya, R. N.; Batchelor, W.; Contreras, M. A.; Noufi, R. N. (National Renewable Energy Laboratory); Hiltner, J. F. & Sites, J. R. (Department of Physics, Colorado State University)
open access

25-ps neutron detector for measuring ICF-target burn history

Description: We have developed a fast, sensitive neutron detector for recording the fusion reaction-rate history of inertial-confinement fusion (ICF) experiments. The detector is based on the fast rise-time of a commercial plastic scintillator (BC-422) and has a response < 25 ps FWHM. A thin piece of scintillator material acts as a neutron-to-light converter. A zoom lens images scintillator light to a high-speed (15 ps) optical streak camera for recording. A retractable nose cone positions the scintillator … more
Date: May 2, 1994
Creator: Lerche, R. A.; Phillion, D. W. & Tietbohl, G. L.
open access

The 50 MeV Beam Test Facility at LBL

Description: A new beam line, expected to be built by September 1993, will transport the 50 MeV electron beam from the ALS LINAC into an experimental area to support various R&D activities in the Center for Beam Physics at LBL. A variety of experiments are planned involving the interaction of such a relativistic electron beam with plasmas (plasma focusing), laser beams (generation of femtosecond X-ray pulses) and electromagnetic cavities (Crab cavities etc....). The beam line is designed using the measured … more
Date: May 1, 1993
Creator: Leemans, W.; Behrsing, G.; Kim, K. J.; Krupnick, J.; Matuk, C.; Selph, F. et al.
open access

100 MW klystron development at SLAC

Description: A klystron designed to operate at 11.4 GHz and 440 kV is presently SLAC's strongest rf power source candidate for the Next Linear Collider. It is expected to provide 100 MW of rf power with a pulse width of 1 microsecond. Many of the conventional tube technologies are being pushed to their limits. High electron beam power densities, rf electric gradients in cavity gaps and stresses on the ceramic rf output windows are among the most severe problems to be dealt with. This paper describes progres… more
Date: May 1, 1991
Creator: Vlieks, A. E.; Callin, R. S.; Caryotakis, G.; Fant, K. S.; Fowkes, W. R.; Lee, T. G. et al.
open access

The 110 GHz ECH Installation on DII-D: Status and Initial Experimental Results

Description: Two 110 GHz gyrotrons with nominal output power of 1 MW each have been installed on the DIII-D tokamak. The gyrotrons, produced by Gycom and Communications and Power Industries, are connected to the tokamak by windowless evacuated transmission lines using circular corrugated waveguide carrying the HE{sub 11} mode. Initial experiments with the Gycom gyrotron showed good central heating efficiency at the second harmonic resonance with record central electron temperatures for DIII-D in excess of 1… more
Date: May 1997
Creator: Lohr, J.; Callis, R. W. & O`Neill, R. C.
open access

350 MW(t) MHTGR preassembly and modularization

Description: The Modular High Temperature Gas Cooled Reactor (MHTGR) provides a safe and economical nuclear power option for the world's electrical generation needs by the turn of the century. The proposed MHTGR plant is composed of four 350 MW(t) prismatic core reactor modules, coupled to a 2(2 {times} 1) turbine generator producing a net plant electrical output of 538 MW(e). Each of the four reactor module is located in a below-ground level concrete silo, and consists of a reactor vessel and a steam gener… more
Date: May 1, 1991
Creator: Venkatesh, M.C. (General Atomics, San Diego, CA (USA)); Jones, G. (Gas-Cooled Reactor Associates, San Diego, CA (USA)); Dilling, D.A. (Bechtel International Corp., San Francisco, CA (USA)) & Parker, W.J. (Stone and Webster Engineering Corp., Boston, MA (USA))
open access

A 600 MeV cyclotron for radioactive beam production

Description: The magnetic field design for a 600 MeV proton cyclotron is described. The cyclotron has a single stage, a normal conducting magnet coil and a 9.8 m outside yoke diameter. It has 8 sectors, with a transition to 4 sectors in the center region. The magnetic field design was done using 1958 Harwell rectangular ridge system measurements and was compared with recent 3-dimensional field calculations with the program TOSCA at NSCL. The center region 4--8 sector transition focussing was also checked wi… more
Date: May 17, 1993
Creator: Clark, D. J.
open access

The 16th Werner Brandt Workshop on charged particle penetration phenomena

Description: This report contains viewgraphs on the following topics: impact parameter dependence of charge transfer and energy loss; nonlinear dynamical response of the electron gas: comparison of some simple theories; stopping of ultrarelativistic ions in solids (33.2-TeV {sup 108}Pb); collective excitation in reduced dimensionality; collective states in atoms and cluster; plasmon coupling with external probes; atomic collisions with antiprotons; layer-number scaling in ultra-thin film stopping and energe… more
Date: May 1, 1996
open access

18th U.S. Department of Energy Low-Level Radioactive Waste Management Conference. Program

Description: This conference explored the latest developments in low-level radioactive waste management through presentations from professionals in both the public and the private sectors and special guests. The conference included two continuing education seminars, a workshop, exhibits, and a tour of Envirocare of Utah, Inc., one of America's three commercial low-level radioactive waste depositories.
Date: May 20, 1997
open access

The 1997 NRC IST workshops and the status of questions and issues directed to the ASME O and M committee

Description: This paper describes the results of the four NRC Inservice Testing (IST) Workshops which were held in early 1997 pertaining to NRC Inspection Procedure P 73756, Inservice Testing of Pumps and Valves. It also presents the status of the ASME code committees` resolution of certain questions forwarded to the ASME by the NRC. These questions relate to code interpretations, inconsistencies in the code, and industry concerns that are most appropriately resolved through the ASME consensus process. The … more
Date: May 1, 1998
Creator: DiBiasio, A. M.
open access

1st-Principles Step- and Kink-Formation Energies on Cu(111)

Description: In rough agreement with experimental values derived from Cu island shapes vs. temperature, ab-initio calculations yield formation energies of 0.27 and 0.26 eV/ step-edge-atom for (100)- and (111)-micro facet steps on Cu(lll), and 0.09 and 0.12 eV per kink in those steps. Comparison to ab-initio results for Al and Pt shows that as a rule, the average formation energy of straight steps on a close-packed metal surface equals -7% of the metal's cohesive energy.
Date: May 26, 1999
Creator: Feibelman, Peter J.
open access

3D-modeling for the LANL-APT RFQ

Description: An 8-m-long 4-vane radio frequency quadrupole (RFQ) has been proposed by LANL for use in high-current proton accelerators. This RFQ is made up of four 2-m-long coupled segments; the end regions and segment joints need full 3D modeling. In this paper, the strategies for piecewise treatment of the RFQ and results of the modeling are presented.
Date: May 1, 1996
Creator: Krawczyk, F. L. & Young, L. M.
open access

3D numerical thermal stress analysis of the high power target for the SLC Positron Source

Description: The volumetrically nonuniform power deposition of the incident 33 GeV electron beam in the SLC Positron Source Target is hypothesized to be the most likely cause target failure. The resultant pulsed temperature distributions are known to generate complicated stress fields with no known closed-form analytical solution. 3D finite element analyses of these temperature distributions and associated thermal stress fields in the new High Power Target are described here. Operational guidelines based on… more
Date: May 1, 1991
Creator: Reuter, E.M. & Hodgson, J.A.
open access

3D particle simulations of space-charge-dominated beams in HIF accelerator experiments

Description: The development of a high current, heavy-ion beam for inertial confinement fusion requires a detailed understanding of the behavior of the beam, including effects of the large self-fields. This necessity makes particle-in-cell (PIC) simulation the appropriate tool, and for this reason, the three-dimensional PIC/accelerator code WARP3d is being developed. WARP3d has been used extensively to study the creation and propagation of ion beams both to support experiments and for the understanding of b… more
Date: May 1, 1997
Creator: Grote, D. P.; Friedman, A.; Lund, S. M. & Haber, I.
open access

3D unstructured mesh ALE hydrodynamics with the upwind discontinuous galerkin method

Description: The authors describe a numerical scheme to solve 3D Arbitrary Lagrangian-Eulerian (ALE) hydrodynamics on an unstructured mesh using a discontinuous Galerkin method (DGM) and an explicit Runge-Kutta time discretization. Upwinding is achieved through Roe's linearized Riemann solver with the Harten-Hyman entropy fix. For stabilization, a 3D quadratic programming generalization of van Leer's 1D minmod slope limiter is used along with a Lapidus type artificial viscosity. This DGM scheme has been tes… more
Date: May 7, 1999
Creator: Kershaw, D S; Milovich, J L; Prasad, M K; Shaw, M J & Shestakov, A I
open access

A 3He{sup +}{sup +} RFQ accelerator for the production of PET isotopes

Description: Project status of the 3He{sup +}{sup +} 10.5 MeV RFQ Linear Accelerator for the production of PET isotopes will be presented. The accelerator design was begun in September of 1995 with a goal of completion and delivery of the accelerator to BRF in Shreveport, Louisiana by the summer of 1997. The design effort and construction is concentrated in Lab G on the Fermilab campus. Some of the high lights include a 25 mA peak current 3He` ion source, four RFQ accelerating stages that are powered by sur… more
Date: May 1, 1997
Creator: Pasquinelli, R.J. & Collaboration, E887
open access

Ab initio molecular orbital calculations of molten salt vapor complexes using Gaussian-2 theory: LiAlF{sub 4} and NaAlF{sub 4}

Description: The structures and energies of the molten salt vapor complexes LiAlF{sub 4} and NaAlF{sub 4} are studied using new high level ab initio molecular orbital methods. The structures are determined using Moller-Plesset perturbation theory to second-order and the total energies are determined using a recently introduced modification of Gaussian-2 (G2) theory. The total energies are used to determine relative energies of the corner-, edge-, and face-bridged structures and accurate reaction energies. T… more
Date: May 1993
Creator: Curtiss, L. A.
open access

Absolute, soft x-ray calorimetry on the Z facility at Sandia National Laboratories

Description: Simple and reliable x-ray fluence measurements, in addition to time-resolved diagnostics, are needed to understand the physics of hot Z-pinch plasmas. A commercially available laser calorimeter has been modified for measuring soft x-ray fluence from the Z facility at Sandia National Laboratories. The x-ray absorber of this calorimeter is an aluminum disk, attached to a two-dimensional thermopile and surrounded by an isoperibol shroud. The time-integral and the maximum of the thermopile voltage … more
Date: May 1, 1998
Creator: Fehl, D. L.; Muron, D. J.; Leeper, R. J.; Chandler, G. A.; Deeney, C. & Spielman, R. B.
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