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Universal formula for the quasistatic second-order density perturbation by a cold magnetoplasma wave

Description: Using the general expression for the ponderomotive Hamiltonian, the quasi-static quasi-neutral density change caused by the ponderomotive force of a cold magnetoplasma wave of arbitrary frequency and polarization is obtained. This formula agrees with and extends previous results for unmagnetized and magnetized plasma.
Date: December 16, 1977
Creator: Kaufman, A. N.; Cary, J. R. & Pereira, N. R.
Partner: UNT Libraries Government Documents Department
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An IFE development strategy

Description: The development of inertial fusion as a power source will require achieving four principal milestones: ignition and propagating burn; high gain at low drive energy for the reactor driver; pulse repetition rates of a few Hz; and long-term reliability and economics of a reactor. To keep development time and costs to a minimum, these should be accomplished with as few major facilities as possible. A viable scenario for the Inertial Fusion Energy (IFE) Program would include establishing the first m… more
Date: July 16, 1991
Creator: Hogan, W.J.; Storm, E. & Lindl, J.D.
Partner: UNT Libraries Government Documents Department
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New concept for a high-power beam dump

Description: A new concept for a dump for the ion and neutral beams used in the controlled nuclear fusion program uses thin sheets of a refractory metal such as tungsten formed into troughs having semi-circular cross sections. High-velocity water flowing circumferentially removes heat by subcooled nucleate boiling. Possible advantages are modular construction, lower water-pumping power, and a lower pressure drop than in conventional beam dumps. An example design calculation is shown for a dump capable of ab… more
Date: April 16, 1980
Creator: Moir, R.W. & Taylor, C.E.
Partner: UNT Libraries Government Documents Department
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Magnetic shielding tests for MFTF-B neutral beamlines

Description: A test program to determine the effectiveness of various magnetic shielding designs for MFTF-B beamlines was established at Lawrence Livermore National Laboratory (LLNL). The proposed one-tenth-scale shielding-design models were tested in a uniform field produced by a Helmholtz coil pair. A similar technique was used for the MFTF source-injector assemblies, and the model test results were confirmed during the Technology Demonstration in 1982. The results of these tests on shielding designs for … more
Date: November 16, 1983
Creator: Kerns, J.; Fabyan, J.; Wood, R. & Koger, P.
Partner: UNT Libraries Government Documents Department
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Richtmyer-Meshkov instabilities in stratified fluids

Description: We present an analytic theory of Richtmyer-Meshkov instabilities in an arbitrary number N of stratified fluids subjected to a shock. Following our earlier work on Rayleigh-Taylor instabilities, the theory assumes incompressible flow in which a shock is treated an impulsive acceleration, g = ..delta.. v delta(tau/sub s), ..delta..v being the jump velocity induced in the system by a shock at time tau/sub s/. We discuss the special cases N = 2 and N = 3, and illustrate both Rayleigh-Taylor and Ric… more
Date: December 16, 1983
Creator: Mikaelian, K.O.
Partner: UNT Libraries Government Documents Department
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Acceleration of compact torus plasma rings in a coaxial rail-gun

Description: We discuss here theoretical studies of magnetic acceleration of Compact Torus plasma rings in a coaxial, rail-gun accelerator. The rings are formed using a magnetized coaxial plasma gun and are accelerated by injection of B/sub theta/ flux from an accelerator bank. After acceleration, the rings enter a focusing cone where the ring is decelerated and reduced in radius. As the ring radius decreases, the ring magnetic energy increases until it equals the entering kinetic energy and the ring stagna… more
Date: May 16, 1985
Creator: Hartman, C. W.; Hammer, J. H. & Eddleman, J.
Partner: UNT Libraries Government Documents Department
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Three wavelength optical alignment of the Nova laser

Description: The Nova laser, presently under construction at Lawrence Livermore National Laboratory, will be capable of delivering more than 100 kJ of focused energy to an Inertial Confinement Fusion (ICF) target. Operation at the fundamental wavelength of the laser (1.05 ..mu..m) and at the second and third harmonic will be possible. This paper will discuss the optical alignment systems and techniques being implemented to align the laser output to the target at these wavelengths prior to each target irradi… more
Date: November 16, 1983
Creator: Swift, C. D.; Bliss, E. S.; Jones, W. A. & Seppala, L. G.
Partner: UNT Libraries Government Documents Department
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Implicit methods in particle simulation

Description: This paper surveys recent advances in the application of implicit integration schemes to particle simulation of plasmas. The use of implicit integration schemes is motivated by the goal of efficiently studying low-frequency plasma phenomena using a large timestep, while retaining accuracy and kinetics. Implicit schemes achieve numerical stability and provide selective damping of unwanted high-frequency waves. This paper reviews the implicit moment and direct implicit methods. Lastly, the mergin… more
Date: March 16, 1982
Creator: Cohen, B.I.
Partner: UNT Libraries Government Documents Department
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Projections of transport scaling laws for small toroidal reactors

Description: Transport in present day Spheromaks is dominated by impurity radiation. Fortunately, this is largely from oxygen and carbon, not metal vapor from the walls of the vessel on plasma guns and it is expected this loss can be eliminated by improved technique. The formation and gross MHD stability properties of these plasmas are quite well understood and so the reactor predictions depend on estimates of the energy loss rates from the plasma. In the absence of significant experimental data one is driv… more
Date: November 16, 1981
Creator: McNamara, B.
Partner: UNT Libraries Government Documents Department
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Laser fusion experiments at LLL

Description: These notes present the experimental basis and status for laser fusion as developed at LLL. Two other chapters, one authored by K.A. Brueckner and the other by C. Max, present the theoretical implosion physics and laser plasma interaction physics. The notes consist of six sections. The first is an introductory section which provides some of the history of inertial fusion and a simple explanation of the concepts involved. The second section presents an extensive discussion of diagnostic instrume… more
Date: June 16, 1980
Creator: Ahlstrom, H.G.
Partner: UNT Libraries Government Documents Department
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Soft x-ray measurement of internal tearing mode structure in a reversed-field pinch

Description: The structure of internally resonant tearing modes has been studied in the Madison Symmetric Torus reversed-field pinch with a soft x-ray detector system consisting of an imaging array at one toroidal location and several detectors at different toroidal locations. The toroidal mode numbers of m = 1 structures are in the range n = {minus}5, {minus}6, {minus}7. The modes propagate with phase velocity v = 1--6 {times} 10{sup 6} cm/s, larger than the diamagnetic drift velocity v{sub d} {approximate… more
Date: September 16, 1991
Creator: Chartas, G. & Hokin, S.
Partner: UNT Libraries Government Documents Department
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Improving the bulk laser-damage resistance of KDP by baking and pulsed-laser irradiation

Description: Isolated bulk damage centers are produced when KDP crystals are irradiated by 1-ns 1064-nm pulses. We have tested about 100 samples and find the median threshold to be 7 J/cm/sup 2/ when the samples are irradiated only once at each test volume (1-on-1 tests). The median threshold increased to 11 J/cm/sup 2/ when the test volumes were first subjected to subthreshold laser irradiation (n-on-1 tests). We baked several crystals at temperatures from 110 to 165/sup 0/C and remeasured their thresholds… more
Date: September 16, 1981
Creator: Swain, J.E.; Stokowski, S.E.; Milam, D. & Rainer, F.
Partner: UNT Libraries Government Documents Department
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Irradiation response of materials. Final Quarterly technical progress report

Description: The simultaneous production of helium from (n,..cap alpha..) reactions and atomic displacement damage by energetic neutrons in reactor structural alloys is expected to have a strong influence on their irradiation response for first wall and structural applications in fusion power reactors. Charged particle bombardment offers the possibility of assessing the phenomenology and mechanisms of microstructural evolution in a wide range of materials exposed to simultaneous helium injection and creatio… more
Date: October 16, 1981
Creator: Spitznagel, J. A.; Wood, S. & Choyke, W. J.
Partner: UNT Libraries Government Documents Department
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Inertial-confinement-fusion targets

Description: Inertial confinement fusion (ICF) targets are made as simple flat discs, as hollow shells or as complicated multilayer structures. Many techniques have been devised for producing the targets. Glass and metal shells are made by using drop and bubble techniques. Solid hydrogen shells are also produced by adapting old methods to the solution of modern problems. Some of these techniques, problems and solutions are discussed. In addition, the applications of many of the techniques to fabrication of … more
Date: November 16, 1981
Creator: Hendricks, C.D.
Partner: UNT Libraries Government Documents Department
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Development of ITER 15 MA ELMy H-mode Inductive Scenario

Description: The poloidal field (PF) coil system on ITER, which provides both feedforward and feedback control of plasma position, shape, and current, is a critical element for achieving mission performance. Analysis of PF capabilities has focused on the 15 MA Q = 10 scenario with a 300-500 s flattop burn phase. The operating space available for the 15 MA ELMy H-mode plasma discharges in ITER and upgrades to the PF coils or associated systems to establish confidence that ITER mission objectives can be reach… more
Date: October 16, 2008
Creator: Kessel, C. E.; Campbell, D.; Gribov, Y.; Saibene, G.; Ambrosino, G.; Casper, T. et al.
Partner: UNT Libraries Government Documents Department
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New experimental measurements of electron clouds in ion beams with large tune depression

Description: We study electron clouds in high perveance beams (K = 8E-4) with a large tune depression of 0.2 (defined as the ratio of a single particle oscillation response to the applied focusing fields, with and without space charge). These 1 MeV, 180 mA, K+ beams have a beam potential of +2 kV when electron clouds are minimized. Simulation results are discussed in a companion paper [J-L. Vay, this Conference]. We have developed the first diagnostics that quantitatively measure the accumulation of electro… more
Date: March 16, 2006
Creator: Molvik, A W; Covo, M K; Cohen, R H; Friedman, A; Bieniosek, F M; Leister, C M et al.
Partner: UNT Libraries Government Documents Department
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Hyper-filter-fluorescer spectrometer for fusion x-ray diagnostics

Description: The filter-fluorescer spectrometer (FFS) is a powerful tool for measuring x-ray spectrum from high fluence x-ray sources. However, this technique is limited to energies less than 120 keV, because there are no practical absorption edges available above this energy. In this paper, we present a new method of utilizing the filter-fluorescer system for x-ray spectral measurement above 120 keV. The new apparatus is called hyper-filter-fluorescer spectrometer (HFFS).
Date: June 16, 1981
Creator: Wang, C. L.
Partner: UNT Libraries Government Documents Department
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Demountable vacuum seals for fusion reactor applications

Description: Demountable vacuum seals for fusion reactor applications must be compatible with the reactor environment, easily scalable, very reliable and readily maintained by remote handling methods. We are investigating gate valves as well as flanges in our efforts to provide such seals. They are all metal and scalable without becoming massive and require no axial fasteners. Preliminary tests on an initial 30 cm aluminum flange using no soft metal coatings or gaskets have given several vacuum tight closur… more
Date: October 16, 1987
Creator: Batzer, T. H. & Call, W. R.
Partner: UNT Libraries Government Documents Department
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Overview of the TIBER II (Tokamak Ignition/Burn Experimental Reactor) design

Description: The TIBER II Tokamak Ignition/Burn Experimental Reactor design is the result of efforts by numerous people and institutions, including many fusion laboratories, universities, and industries. While subsystems will be covered extensively in other reports, this overview will attempt to place the work in perspective. Major features of the design are compact size, low cost, and steady-state operation. These are achieved through plasma shaping and innovative features such as radiation tolerant magnet… more
Date: October 16, 1987
Creator: Henning, C. D. & Logan, B. G.
Partner: UNT Libraries Government Documents Department
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Chamber propagation

Description: Propagation of a heavy ion beam to the target appears possible under conditions thought to be realizable by several reactor designs. Beam quality at the lens is believed to provide adequate intensity at the target -- but the beam must pass through chamber debris and its self fields along the way. This paper reviews present consensus on propagation modes and presents recent results on the effects of photoionization of the beam ions by thermal x-rays from the heated target. Ballistic propagation … more
Date: January 16, 1991
Creator: Langdon, B.
Partner: UNT Libraries Government Documents Department
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The need for a fusion technology information program

Description: In providing an adequate energy technology for the future, which new programs should be considered by the Department of Energy national laboratories to ensure that the US remains in the forefront of international science and technology is an important question. This paper suggests that the urgency for energy independence demands an active communication program that would increase awareness of energy as a critical national issue and would present fusion, with its benefits and risks, as one of th… more
Date: June 16, 1987
Creator: Correll, D.L. Jr.
Partner: UNT Libraries Government Documents Department
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Some observations concerning alpha instabilities and driven tokamak reactors

Description: While much research is needed to assess the reality and consequences of alpha-induced instabilities, crude transport estimates for the TAE mode indicate that as little as 10 percent of the alpha energy would be deposited in steady-state. Even so, CIT and the ITER technology phase would meet their minimal goals of Q = 5 if only the alphas themselves are ejected and not the fuel itself. Higher gain up to Q {approximately} 20 may be possible in driven reactors of a different design, depending on t… more
Date: July 16, 1990
Creator: Fowler, T.K. (California Univ., Berkeley, CA (USA))
Partner: UNT Libraries Government Documents Department
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Design of neutron streak camera for fusion diagnostics

Description: In laser fusion, such as with the NOVA under construction at the Lawrence Livermore National Laboratory, the D-T reaction is expected to be complete within 100 ps. It is important to measure the time-dependence of the neutron flux from the fusion target. We describe the design of a new neutron detector of 20 ps resolving time that can be used to study the history of fusion burn.
Date: June 16, 1981
Creator: Wang, C. L.; Kalibjian, R. & Singh, M. S.
Partner: UNT Libraries Government Documents Department
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