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Magnetic design of the axisymmetric throttle-coil addition to the tandem mirror experiment-upgrade

Description: The TMX-U magnet set has incorporated new axisymmetric throttle coils and fan-reversing transition magnets. This new magnet geometry, which will allow for the experimental verification of new physics issues related to axicell tandem mirrors, encompasses both engineering and physics considerations. Engineering considerations include structural integrity plus neutral beam and diagnostic access. Physics issues include the stability and radial transport of the confined plasma. We have calculated th… more
Date: November 28, 1983
Creator: Wong, R.L.
Partner: UNT Libraries Government Documents Department
open access

State of California initiative in geothermal development: its objectives, accomplishments and schedules

Description: California has the most abundant known reserves of geothermal resources in the nation, and California State government has taken several important actions to accelerate the environmentally acceptable development of geothermal energy. The roles played by various California State government agencies and the legislature to accomplish this goal are discussed.
Date: November 28, 1978
Creator: Reed, C. S.
Partner: UNT Libraries Government Documents Department
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Sharp Reduction of the Secondary Electron Emission Yield from Grooved Surfaces

Description: The effect of an artificially-enhanced rough surface on the secondary electron emission yield (SEY) was investigated both theoretically and experimentally. Analytical studies on triangular and rectangular grooved surfaces show the connection between the characteristic parameters of a given geometry to the SEY reduction. The effect of a strong magnetic field is also discussed. SEY of grooved samples have been measured and the results agree with Monte-Carlo simulations.
Date: November 28, 2007
Creator: Pivi, M. T. F.; King, F. K.; Kirby, R. E.; Ruabenheimer, T. O.; Stupakov, G. & Le Pimpec, F.
Partner: UNT Libraries Government Documents Department
open access

An Incompressible Navier-Stokes with Particles Algorithm andParallel Implementation

Description: We present a variation of an adaptive projection method forcomputing solutions to the incompressible Navier-Stokes equations withsuspended particles. To compute the divergence-free component of themomentum forcing due to the particle drag, we employ an approach whichexploits the locality and smoothness of the Laplacian of the projectionoperator applied to the discretized particle drag force. We presentconvergence and performance results to demonstrate the effectiveness ofthis approach.
Date: November 28, 2006
Creator: Martin, Daniel F.; Colella, Phillip & Keen, Noel D.
Partner: UNT Libraries Government Documents Department
open access

Search for CPT and Lorentz Violation in B0-B0bar Oscillations with Dilepton Events

Description: We report results of a search for CPT and Lorentz violation in B{sup 0}-{bar B}{sup 0} oscillations using inclusive dilepton events from 232 million {Upsilon}(4S) {yields} B{bar B} decays recorded by the BABAR detector at the PEP-II B Factory at SLAC. We find 2.8{sigma} significance, compatible with no signal, for variations in the complex CPT violation parameter z at the Earth's sidereal frequency and extract values for the quantities {Delta}a{sub {mu}} in the general Lorentz-violating standar… more
Date: November 28, 2007
Creator: Collaboration, The BABAR & Aubert, B.
Partner: UNT Libraries Government Documents Department
open access

Optical Damage Threshold of Silicon for Ultrafast Infrared Pulses

Description: We present measurements of the optical damage threshold of crystalline silicon in air for ultrafast pulses in the near infrared. The wavelengths tested span a range from the telecommunications band at 1550 nm, extending to 2260 nm. We discuss the motivation for the measurements and give theoretical context. We then describe the experimental setup, diagnostics, and procedure. The results show a breakdown threshold of 0.2J/cm{sup 2} at 1550 nm and 1.06 ps FWHM pulse duration, and a weak dependenc… more
Date: November 28, 2007
Creator: Cowan, Benjamin M. & /Tech-X, Boulder /SLAC
Partner: UNT Libraries Government Documents Department
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Highly Effective Polarized Electron Sources Based on Strained Semiconductor Superlattice with Distributed Bragg Reflector

Description: Resonance enhancement of the quantum efficiency of new polarized electron photocathodes based on a short-period strained superlattice structures is reported. The superlattice is a part of an integrated Fabry-Perot optical cavity. We demonstrate that the Fabry-Perot resonator enhances the quantum efficiency by the order of magnitude in the wavelength region of the main polarization maximum. The high structural quality implied by these results points to the very promising application of these pho… more
Date: November 28, 2007
Creator: Gerchikov, L. G.; Aulenbacher, K.; Clendenin, J. E.; Kuz'michev, V. V.; Mamaev, Yu. A.; Maruyama, T. et al.
Partner: UNT Libraries Government Documents Department
open access

Summary of Polarized e-/e+ Source Presentations

Description: The development of polarized electron sources in the 1970s capable of generating beams for injection into electron accelerators has been a major enabling factor for spin physics with electrons during the past quarter century. These sources continue to be refined for higher polarization and better operability. Recent developments were presented at this workshop in both plenary sessions and in 2 separate parallel sessions. The ILC plans to utilize not only a polarized electron source but also a p… more
Date: November 28, 2007
Creator: Clendenin, J. E.
Partner: UNT Libraries Government Documents Department
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Improvements in Monte Carlo Simulation of Large Electron Fields

Description: Two Monte Carlo systems, EGSnrc and Geant4, were used to calculate dose distributions in large electron fields used in radiotherapy. Source and geometry parameters were adjusted to match calculated results with measurement. Both codes were capable of accurately reproducing the measured dose distributions of the 6 electron beams available on the accelerator. Depth penetration was matched to 0.1 cm. Depth dose curves generally agreed to 2% in the build-up region, although there is an additional 2… more
Date: November 28, 2007
Creator: Faddegon, Bruce A.; /UC, San Francisco; Perl, Joseph & Asai, Makoto
Partner: UNT Libraries Government Documents Department
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3C454.3 Revelas the Structure and Physics of its 'Blazar Zone'

Description: Recent multi-wavelength observations of 3C454.3, in particular during its giant outburst in 2005, put severe constraints on the location of the 'blazar zone', its dissipative nature, and high energy radiation mechanisms. As the optical, X-ray, and millimeter light-curves indicate, significant fraction of the jet energy must be released in the vicinity of the millimeter-photosphere, i.e. at distances where, due to the lateral expansion, the jet becomes transparent at millimeter wavelengths. We c… more
Date: November 28, 2007
Creator: Sikora, M.; Moderski, R. & Madejski, G.M.
Partner: UNT Libraries Government Documents Department
open access

Characterization and Electrochemical Performance of SubstitutedLiNi0.4Co0.2-yAlyMn0.4O2 (0<_y<_0.2) Cathode Materials

Description: A complete series of LiNi0.4Co0.2-yAlyMn0.4O2 (0<_y<_0.2) materials have been synthesized and investigated as cathode materials for lithium ion batteries. When cycled between 2.0 and 4.3 V vs. Li/Li+ at a current density of 0.1 mA/cm2, stable capacities of ~;;160 mAh/g for y=0 to ~;;110 mAh/g for y=0.2 are achieved. Upon increasing the current density, it is found that all materials containing aluminum show reduced polarization and improved rate performance. The optimal performance at all… more
Date: November 28, 2007
Creator: Wilcox, James D. & Doeff, Marca M.
Partner: UNT Libraries Government Documents Department
open access

Commissioning the LCLS Injector

Description: The Linac Coherent Light Source (LCLS) is a SASE x-ray Free-Electron Laser (FEL) project presently under construction at SLAC. The injector section, from drive laser and RF photocathode gun through first bunch compressor chicane, was installed in fall 2006. Initial system commissioning with an electron beam was completed in August 2007, with the goal of a 1.2-micron emittance in a 1-nC bunch clearly demonstrated. The second phase of commissioning, including second bunch compressor and full lina… more
Date: November 28, 2007
Creator: Akre, R.; Dowell, D.; Emma, P.; Frisch, J.; Gilevich, S.; Hays, G. et al.
Partner: UNT Libraries Government Documents Department
open access

Parametric Modeling of Electron Beam Loss in Synchrotron Light Sources

Description: Synchrotron light is used for a wide variety of scientific disciplines ranging from physical chemistry to molecular biology and industrial applications. As the electron beam circulates, random single-particle collisional processes lead to decay of the beam current in time. We report a simulation study in which a combined neural network (NN) and first-principles (FP) model is used to capture the decay in beam current due to Touschek, Bremsstrahlung, and Coulomb effects. The FP block in the combi… more
Date: November 28, 2007
Creator: Sayyar-Rodsari, B.; Schweiger, C.; Hartman, E.; Corbett, J.; Lee, M.; Lui, P. et al.
Partner: UNT Libraries Government Documents Department
open access

Bunch Length Measurements in SPEAR3

Description: A series of bunch length measurements were made in SPEAR3 for two different machine optics. In the achromatic optics the bunch length increases from the low-current value of 16.6ps rms to about 30ps at 25ma/bunch yielding an inductive impedance of -0.17{Omega}. Reducing the momentum compaction factor by a factor of {approx}60 [1] yields a low-current bunch length of {approx}4ps rms. In this paper we review the experimental setup and results.
Date: November 28, 2007
Creator: Corbett, W.J.; Fisher, A.; Huang, X.; Safranek, J.; Sebek, J.; /SLAC et al.
Partner: UNT Libraries Government Documents Department
open access

Normal zone detectors for a large number of inductively coupled coils

Description: In order to protect a set of inductively coupled superconducting magnets, it is necessary to locate and measure normal zone voltages that are small compared with the mutual and self-induced voltages. The method described in this paper uses two sets of voltage measurements to locate and measure one or more normal zones in any number of coupled coils. One set of voltages is the outputs of bridges that balance out the self-induced voltages. The other set of voltages can be the voltages across the … more
Date: November 28, 1983
Creator: Owen, E. W. & Shimer, D. W.
Partner: UNT Libraries Government Documents Department
open access

Software for reflectivity calculations of x-ray mirrors. Revision 1

Description: With VAX software and the data libraries of Henke and Biggs-Lighthill, we have created a library of atomic scattering factors f/sub 1/ and f/sub 2/ in the energy range 0.1 keV to 10.0 keV. Scattering factor values for the elements Z = 1 to Z = 94 and in the above energy range are stored in a keyed access library (key = element symbol). This library allows one to calculate reflectivity rapidly and fold it with other components in an x-ray detector channel. Additional software allows the library … more
Date: November 28, 1984
Creator: Auerbach, J.M. & Tirsell, K.G.
Partner: UNT Libraries Government Documents Department
open access

Design of the electromagnetic fluctuations diagnostic for MFTF-B

Description: The Electromagnetic Fluctuations (EMF) diagnostic will be used to monitor ion fluctuations which could be unstable in MFTF-B. Each probe assembly includes a high impedance electrostatic probe to measure potential fluctuations, and a group of nested, single turn loops to measure magnetic fluctuations in three directions. Eventually, more probes and loops will be added to each probe assembly for making more detailed measurements. The sensors must lie physically close to the plasma edge and are ra… more
Date: November 28, 1983
Creator: House, P.A.; Goerz, D.A. & Martin, R.
Partner: UNT Libraries Government Documents Department
open access

Numerical simulation of turbulent mixing in shock-tube experiments

Description: We have carried out a number of 2D numerical simulations on an ALE code for shock-tube experiments in which a shock crosses one or more contact discontinuities and, after traveling through a homogeneous medium, reflects off a rigid wall at the end of the shock-tube and re-crosses the contact discontinuity. We have considered two-fluid and three-fluid experiments: the first fluid, which carries the original shock, is air; the other fluids are helium, freon, SF/sub 6/, or air again. Helium is lig… more
Date: November 28, 1988
Creator: Mikaelian, K.O.
Partner: UNT Libraries Government Documents Department
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/sup 163/Dy as a solar neutrino detector

Description: The possibility of using /sup 163/Dy as a low threshold solar neutrino detector is discussed. Solar neutrino absorption cross sections are calculated, and expected capture rates presented.
Date: November 28, 1984
Creator: Bennett, C. L.
Partner: UNT Libraries Government Documents Department
open access

Legal Aspects of National Implementation of the Chemical Weapons Convention

Description: The author discusses some legal aspects of measures at the national level to implement the Chemical Weapons Convention (CWC). These implementing measures are universal, applying not only to the few States Parties that will declare and destroy chemical weapons, but also to the many States Parties that have never had a chemical weapons program. This new need for national measures to implement multilateral arms control agreements has generated unease due to a perception that implementation may be … more
Date: November 28, 1994
Creator: Tanzman, Edward A.; Zeuli, Anthony R. & Kellman, Barry
Partner: UNT Libraries Government Documents Department
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Proton reaction cross sections measured in the BNL/AGS E943 experiment

Description: We have measured proton reaction cross sections over a wide mass and energy range at the Brookhaven AGS accelerator. The samples were elemental Be, C, Al, Cu, W, and Pb; the measurements were carried out at ten incident proton kinetic energies in the range 0.54 to 7.8 GeV. The experiment was similar to an earlier experiment in the 200-550 MeV range by Renberg et al. The new results are in good agreement with those of Renberg et al. at the overlap point near 550 MeV. The combined results of the … more
Date: November 28, 2000
Creator: Dietrich, F S; Hartouni, E P; Schmid, G J; Soltz, R; Abfalterer, W P; Haight, R C et al.
Partner: UNT Libraries Government Documents Department
open access

Expected Performance of the ATLAS Experiment - Detector, Trigger and Physics

Description: The Large Hadron Collider (LHC) at CERN promises a major step forward in the understanding of the fundamental nature of matter. The ATLAS experiment is a general-purpose detector for the LHC, whose design was guided by the need to accommodate the wide spectrum of possible physics signatures. The major remit of the ATLAS experiment is the exploration of the TeV mass scale where groundbreaking discoveries are expected. In the focus are the investigation of the electroweak symmetry breaking and li… more
Date: November 28, 2011
Creator: Aad, G.; Abat, E.; Abbott, B.; Abdallah, J.; Abdelalim, A. A.; Abdesselam, A. et al.
Partner: UNT Libraries Government Documents Department
open access

Design and Factory Test of the E /E- Frascati Linear Accelerator for DAFNE

Description: The electron-positron accelerator for the DAFNE project has been built and is in test at Titan Beta in Dublin, CA. This S-Band RF linac system utilizes four 45 MW sledded klystrons and 16-3 m accelerating structures to achieve the required performance. It delivers a 4 ampere electron beam to the positron converter and accelerates the resulting positrons to 550 MeV. The converter design uses a 4.3T pulsed tapered flux compressor along with a pseudo-adiabatic tapered field to a 5 KG solenoid over… more
Date: November 28, 2011
Creator: Anamkath, H.; Lyons, S.; Nett, D.; Treas, P.; Whitham, K.; Zante, T. et al.
Partner: UNT Libraries Government Documents Department
open access

Neutronics and mass transport in a chemical reactor associated with controlled thermonuclear fusion reactor

Description: The formation of ozone from oxygen and the dissociation carbon dioxide to carbon monoxide and oxygen is studied in a gamma-neutron chemical process blanket associated with a controlled thermonuclear reactor. Materials used for reactor tube wall will affect the efficiency of the energy absorption by the reactants and consequently the yield of reaction products. Three kinds of materials, aluminum, stainless steel and fiber (Al/sub 2/O/sub 3/)-aluminium are investigated for the tube wall material … more
Date: November 28, 1976
Creator: Dang, V D; Steinberg, M; Lazareth, O W & Powell, J R
Partner: UNT Libraries Government Documents Department
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