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Electron cyclotron resonant heating (ECRH) diagnostic system on TMX

Description: The ECRH diagnostics system monitors the net power delivered to the plasma by four 200-kW gyrotron oscillators, the frequency of each gyrotron, and some operating parameters of the gyrotron power supply system. The combination CAMAC- and GPIB-based data acquisition system is under desktop computer control that provides the capability for data conversion and display. The data acquisition system is also interfaced to the main computer system that acquires and archives the data.
Date: October 20, 1981
Creator: Coffield, F.E. & Griffin, D.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Directions for possible upgrades of the Mirror Fusion Test Facility (MFTF)

Description: The Mirror Fusion Test Facility (MFTF) may be upgraded by extending the time of plasma sustenance in an approach to steady-state operation and/or by increasing the neutral-beam injection energy. Some parameter bounds for these upgrades are discussed as they relate to a definition of the required neutral-beam development.
Date: December 20, 1977
Creator: Damm, C. C.; Coensgen, F. H.; Devoto, R. S.; Molvik, A. W.; Porter, G. D.; Shearer, J. W. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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An Overview of the Motional Stark Effect Diagnostic On DIII-D And Design Work For An ITER MSE

Description: The advanced tokamak research program at DIII-D relies critically on the measurement of the current density profile. This was made possible by the development of a Motional Stark Effect (MSE) polarimeter that was first installed in 1992. Three major upgrades have since occurred, and improvements in our understanding of critical performance issues and calibration techniques are ongoing. In parallel with these improvements, we have drawn on our DIII-D experience to begin studies and design work f… more
Date: September 20, 2007
Creator: Holcomb, C. T.; Allen, S. L.; Makowski, M. A.; Jayakumar, R. J.; Gu, M. F.; Lerner, S. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Probing the Universe with Mirrors That Trick Light

Description: For astrophysicists, stargazing may be different than for most people, who are content to admire a star's beauty or possibly make a wish. More than a few astrophysicists wish they could be closer to the stars--or to at least have more sophisticated probing instruments--to understand more about the universe. Astrophysicists study x-rays originating from our Sun, stars, and supernova remnants to understand the extreme physical processes occurring there. In recent years, Livermore researchers have… more
Date: September 20, 2005
Creator: Hazi, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Status of TMX upgrade diagnostics construction

Description: This report describes the status of the initial TMX Upgrade diagnostics and the state of development of additional diagnostics being prepared for later TMX Upgrade experiments. The initial diagnostic instrument set has been described in the TMX Upgrade Proposal. This set is required to get TMX Upgrade operational and to evaluate its initial performance. Additional diagnostic instruments are needed to then carry out the more detailed experiments outlined by the TMX Upgrade program milestones. Th… more
Date: July 20, 1981
Creator: Hornady, R. S.; Davis, J. C. & Simonen, T. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Anomalous transport in mirror systems

Description: As now being explored for fusion applications confinement systems based on the mirror principle embody two kinds of plasma regimes. These two regimes are: (a) high-beta plasmas, stabilized against MHD and other low frequency plasma instabilities by magnetic-well fields, but characterized by non-Maxwellian ion distributions; (b) near-Maxwellian plasmas, confined electrostatically (as in the tandem mirror) or in a field-reversed region within the mirror cell. Common to both situations are the que… more
Date: August 20, 1979
Creator: Post, Richard F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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X-Ray Reflectivity vs Mirror Surface Quality

Description: In an attempt to correlate x ray reflectivity with carbon mirror surface quality the relative reflectivity of five mirrors of different smoothness and optical flatness is compared. Measured and theoretical reflectivity values are in agreement for mirror smoothness <30 A and optical flatness <1000 A. Other correlation could not be established. 4 references.
Date: January 20, 1979
Creator: Stoering, J. P.; Rice, M.; Burginyon, G. A.; Crabb, R.; Augusta, E. L. & Wang, C. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Steps toward increasing Q in mirror systems

Description: Experiments such as the 2XIIB experiment at Livermore have established the ability of mirror systems to confine high temperature, high density plasmas at central beta values exceeding unity. Given these results the next tasks for the mirror approach are to explore means for increasing the energy gain factor Q and to scale up the plasma volume, both of these requirements deriving from economic constraints. This report discusses means for increasng Q, including recent improvements in the tandem m… more
Date: August 20, 1979
Creator: Post, Richard F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Manufacturing of neutral beam sources at Lawrence Livermore Laboratory

Description: Over 50 neutral beam sources (NBS) of the joint Lawrence Berkeley Laboratory (LBL)/Lawrence Livermore Laboratory (LLL) design have been manufactured, since 1973, in the LLL Neutral Beam Source Facility. These sources have been used to provide start-up and sustaining neutral beams for LLL mirror fusion experiments, including 2XIIB, TMX, and Beta II. Experimental prototype 20-kV and 80-kV NBS have also been designed, built, and tested for the Mirror Fusion Test Facility (MFTF). (MOW)
Date: November 20, 1979
Creator: Baird, E.D.; Duffy, T.J.; Harter, G.A.; Holland, E.D.; Kloos, W.A. & Pastrone, J.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Alternative connections for the large MFTF-B solenoids

Description: The MFTF-B central-cell solenoids are a set of twelve closely coupled, large superconducting magnets with similar but not exactly equal currents. Alternative methods of connecting them to their power supplies and dump resistors are investigated. The circuits are evaluated for operating conditions and fault conditions. The factors considered are the voltage to ground during a dump, short circuits, open circuits, quenches, and failure of the protection system to detect a quench. Of particular int… more
Date: May 20, 1983
Creator: Owen, E. W.; Shimer, D. W. & Wang, S. T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Computer simulation of radial transport in tandem mirror machines

Description: A code used for simulation of classical radial transport in the 2XIIB experiment has been modified to simulate radial transport in TMX. Results have been obtained using classical transport coefficients and also using very simple trial neoclassical resonant transport coefficients. Comparison of the results obtained with solely classical transport and with both classical and neo-classical transport indicate that neoclassical transport depresses the ion density by approximately 5%. The central cel… more
Date: February 20, 1979
Creator: Gilmore, J.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Elimination of output-current transients in the MFTF sustaining neutral-beam-arc power supplies

Description: The twenty-three (23) MFTF sustaining neutral beam arc power supplies were designed to provide 0.3 to 30 second output pulses over a range of 24 to 71 volts and 600 to 4000 amperes at 10 percent duty. For economic reasons, the circuit design consists of a 12 pulse rectifier which is asynchronously switched on and off by a three phase electromechanical contactor in the primary ac input. The paper describes the analysis of the problem, various possible solutions considered, and the simple and ine… more
Date: October 20, 1981
Creator: Van Ness, H. W.; Mayhall, D. J. & Wilson, J. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effect of non-adiabaticity of alpha particles in the axisymmetric cusp TMR

Description: One of the end plug configurations we have investigated for use in a tandem mirror reactor is the axisymmetric cusp. We show that because of non-adiabaticity, the containment of 3.5 MeV alpha particles in this configuration is insufficient for the attainment of acceptable plasma performance.
Date: July 20, 1981
Creator: Carlson, Gustav A. & Barr, William L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Continuous cryopump for steady-state Mirror Fusion Reactors

Description: The characteristics of Mirror Fusion Reactors, i.e., steady state operation, a low neutral gas density and a large gas throughput require unique vacuum pumping capabilities. One approach that appears to meet these requirements is a liquid helium cooled cryopump system in which a fixed portion can be isolated and degassed while the remainder continues to pump. The time to degas a rotating, fixed portion of the pumping area and the ratio of that area to the total area fixes the gas inventory in t… more
Date: September 20, 1982
Creator: Batzer, T. H. & Call, W. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Generalized energy principle for flute perturbations in axisymmetric mirror machines

Description: Axial symmetry is a very desirable property of the mirror devices both for fusion and neutron source applications. The main obstacle to be circumvented in the development of such systems, is the flute instability of axisymmetric mirrors. In recent years there appeared a number of proposals, devoted to the stabilization of the flute perturbations in the framework of axisymmetric magnetic configurations, which are based on the combining of the MHD unstable central cell with various types of end-c… more
Date: January 20, 1993
Creator: Lansky, I. M. & Ryutov, D. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Structural Characterization and Lifetime Stability of Mo/Y Extreme Ultraviolet Multilayer Mirrors

Description: We observe a dramatic dependence of the extreme ultraviolet (EUV) reflectivity of Mo/Y multilayers on the oxygen content of yttrium. This is explained by a change in microstructure, increase in roughness of the Y layers and not by an increase in absorption due to oxygen in Y layers. We find best reflectivity of 38.4% is achieved with an oxygen content of 25%, which reduces to 32.6% and 29.6% for multilayers manufactured from oxygen free yttrium and 39%-oxygen yttrium, respectively. These result… more
Date: May 20, 2004
Creator: Kjornrattanawanich, B & Bajt, S
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Programmable controllers replace relays in MFTF-B personnel-safety interlocks

Description: This paper describes a new approach for implementing personnel safety interlocks logic using industrial-type programmable controllers. The logic for all personnel safety interlocks except those totally internal to a subsystem is implemented in two non-redundant controllers. A high degree of fail-safe reliability is achieved by augmenting the protective features intrinsic to each controller with those provided by a small amount of external support hardware. The controllers are interfaced to the … more
Date: October 20, 1981
Creator: Branum, J. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Preface to International Workshop on X-ray Mirror Design, Fabrication, and Metrology

Description: The International Workshop on X-Ray Mirror Design, Fabrication, and Metrology (IWXM), Osaka, Japan, was held as a satellite meeting of the Conference on Synchrotron Radiation Instrumentation (SRI) 2009, Melbourne, Australia, in October, 2009. The workshop was organized by a collaboration of scientists from a number of leading synchrotron institutions and universities around the World, such as Osaka University, SPring-8, KEK (Japan), ALS, APS and NSLS (USA), ELETTRA (Italy), ESRF, Synchrotron SO… more
Date: April 20, 2010
Creator: Yamauchi, Kazuto; Yashchuk, Valeriy V. & Cocco, Daniele
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Laser-start-up system for magnetic mirror fusion

Description: A CO/sub 2/ laser system has been developed at LLL to provide hot start-up plasmas for magnetic mirror fusion experiments. A frozen ammonia pellet is irradiated with a laser power density in excess of 10/sup 13/ W/cm/sup 2/ in a 50-ns pulse. This system uses commercially available laser systems. Optical components were fabricated both by direct machining and standard techniques. The technologies used in this system are directly applicable to reactor scale systems.
Date: May 20, 1976
Creator: Frank, A. M.; Thomas, S. R.; Denhoy, B. S. & Chargin, A. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Modeling Results for Proposed NSTX 28 GHz and EBWH System

Description: A 28 GHz electron cyclotron heating (ECH) and electron Bernstein wave heating (EBWH) system has been proposed for installation on the National Spherical Torus Experiment (NSTX). A 350 kW gyrotron connected to a fixed horn antenna is proposed for ECH-assisted solenoid-free plasma startup. Modeling predicts strong first pass on-axis EC absorption, even for low electron temperature, Te ~ 20 eV, Coaxial Helicity Injection (CHI) startup plasmas. ECH will heat the CHI plasma to Te ~ 300 eV, providing… more
Date: March 20, 2008
Creator: Taylor, G; Ellis, R A; Fredd, E; Greenough, N; Hosea, J C; Wilgen, J B et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The SLS optics beamline

Description: A multipurpose beamline for tests and developments in the field of x-ray optics and synchrotron radiation instrumentation in general is under construction at the Swiss Light Source (SLS) bending magnet X05DA. The beamline uses a newly developed UHV compatible, 100 mm thick, brazed CVD diamond vacuum window. The very compact cryogenically cooled channel cut Si(111) monochromator and bendable 1:1 toroidal focusing mirror at 7:75 m from the source point are installed inside the shielding tunnel. T… more
Date: May 20, 2006
Creator: Flechsig, U.; Abela, R.; Betemps, R.; Blumer, H.; Frank, K.; Jaggi, A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Progress on PEEM3 - An Aberration Corrected X-Ray PhotoemissionElectron Microscope at the ALS

Description: A new ultrahigh-resolution photoemission electron microscope called PEEM3 is being developed and built at the Advanced Light Source (ALS). An electron mirror combined with a much-simplified magnetic dipole separator is to be used to provide simultaneous correction of spherical and chromatic aberrations. It is installed on an elliptically polarized undulator (EPU) beamline, and will be operated with very high spatial resolution and high flux to study the composition, structure, electric and magn… more
Date: May 20, 2006
Creator: MacDowell, Alastair A.; Feng, J.; DeMello, A.; Doran, A.; Duarte,R.; Forest, E. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Wave-driven Countercurrent Plasma Centrifuge

Description: A method for driving rotation and a countercurrent flow in a fully ionized plasma centrifuge is described. The rotation is produced by radiofrequency waves near the cyclotron resonance. The wave energy is transferred into potential energy in a manner similar to the α channeling effect. The countercurrent flow may also be driven by radiofrequency waves. By driving both the rotation and the flow pattern using waves instead of electrodes, physical and engineering issues may be avoided.
Date: March 20, 2009
Creator: Fisch, A.J. Fetterman and N.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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