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Plasma Science, IEEE Transactions on

Issue 1 • Date Feb. 2004

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Displaying Results 1 - 25 of 29
  • Table of contents

    Publication Year: 2004 , Page(s): c1 - 1
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    Freely Available from IEEE
  • IEEE Transactions on Plasma Science publication information

    Publication Year: 2004 , Page(s): c2
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  • Guest Editorial Special Issue on Plenary and Invited Papers From ICOPS 2003

    Publication Year: 2004 , Page(s): 2 - 3
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  • On the physics of lightning

    Publication Year: 2004 , Page(s): 4 - 17
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (376 KB) |  | HTML iconHTML  

    This paper discusses three issues related to lightning. The first is to provide a quantitative physical explanation of the lightning stepped leader, whereby breakdown from a cloud to the ground proceeds by luminous steps about 50 m in length, with about 50 μs separating each step. The second is to explain the initiation of upward leaders from tall objects on the ground, induced by the downward leaders from the cloud. Of particular importance is the concept of "critical radius," used in calculations for the effective attractive radius for the collection of lightning by lightning rods. The third, is the unresolved issue of "ball lightning," where observations have been reported during thunderstorms of luminous spheres of plasma a few centimeters in diameter, moving about 1 m above the ground for periods of up to 10 s, existing inside houses and even aeroplanes. Approximate quantitative calculations are given as proposed explanations of these phenomena, using numerical calculations based on the continuity equations for electrons and ions and also Poisson's Equation to account for space charge effects. Also used are the two material properties of air that at 1 bar the electric field to initiate breakdown is 2.5 MV/m (25 kV/cm) and the field required to sustain a glow discharge is 0.5 MV/m (5 kV/cm). View full abstract»

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  • Experimental and numerical analysis of streamers in pulsed corona and dielectric barrier discharges

    Publication Year: 2004 , Page(s): 18 - 24
    Cited by:  Papers (16)
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    Streamer characteristics have been experimentally and numerically analyzed for pulsed-corona discharge (PCD) and dielectric-barrier discharge (DBD) to find out how the discharge methods determine them and how they, in turn, affect the generation of radicals in flue gases. Experiments have been performed and compared for decomposition of a nitrogen oxide (NO) using PCD and DBD, and the electric field and average electron energy in the streamer are measured in each discharge by using the line ratio of N2+ to N2*. The measured results of electron energy reasonably explain in terms of "G-value" how the measured NO removal efficiencies have come out. The PCD having high electron energy turns out to be more efficient for generating N radicals, whereas the DBD containing relatively low electron energy is more effective for producing O radicals. Three-dimensional (3-D) and one-dimensional (1-D) numerical simulations have been carried out to understand the observed streamer dynamics in both the PCD and DBD reactors. The 3-D numerical simulation has successfully illustrated the images of streamer front propagation in a wire-cylinder PCD reactor. In the 1-D simulation for the DBD, the recurrence phenomena of streamers have numerically appeared during the rising phase of an AC voltage. Furthermore, these numerical models have properly predicted the electric fields that are comparable with the corresponding average electron energies estimated from the emission spectral measurements for the PCD and DBD. View full abstract»

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  • Diagnostics of NO oxidation process in a nonthermal plasma reactor: features of DC streamer-corona discharge and NO LIF profile

    Publication Year: 2004 , Page(s): 25 - 31
    Cited by:  Papers (4)
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    Features of the streamer-corona discharge and the NO processing area in corona radical shower system was studied experimentally. The time evolution of the streamer-corona discharges induced by laser irradiations was measured to understand the discharge characteristics responsible for NO removal. Using the wide-range planar laser-induced fluorescence imaging (image size: 240 mm in width and 35 mm in height), two-dimensional distributions of ground-state NO were observed not only at the discharge zone but also both the downstream and the upstream regions of the reactor. The obtained results showed that the density of NO molecules decreased not only in the plasma region formed by the corona streamers and downstream region of the reactor but also in the upstream region of the reactor. In the present reactor at low main gas flow rate, it was considered that electrohydrodynamic (EHD) flow became to be dominant, and the flow toward the upstream affected the decrease of NO in the upstream region. As the EHD-induced secondary flow is correlated with the current flow from the stressed electrode to grounded electrode, the control of the streamers seems to be an important factor for optimizing the reactors used for NOx removal. View full abstract»

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  • Effect of electrode shape in dielectric barrier discharge plasma reactor for NOx removal

    Publication Year: 2004 , Page(s): 32 - 38
    Cited by:  Papers (27)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (272 KB) |  | HTML iconHTML  

    An experimental study on nitrogen oxides (NOx) removal from a simulated diesel engine exhaust gas was carried out in geometry of various electrodes for dielectric barrier discharge reactor to improve the removal efficiency. The electrodes employed in the experiment were a plane, a trench, and a multipoint geometry. The right-pyramids, which were used as multipoint, had 45° tip angle and a height of 1-5 mm. The multipoint electrodes have 528-5000 pyramids in an area of 132 cm2 (22 × 6 cm). The trench electrode has knife-edge rails with 5-mm height and 45° tip angle. The alumina dielectric barrier coated plane electrode was used as a high-voltage electrode, to which a sinusoidal high voltage was applied with frequency of several tens kilohertz. The N2:O2=9:1 mixed gas containing 200-ppm NO was used as simulated gas with gas flow rate of 5 L/min. NO removals in case of the plane and the trench electrodes were lower than that in case of multipoint one. NO removal yield drastically decreases with increasing the number of pyramids on the electrode. NO removal efficiency was almost independent of the pyramid projection height under our experimental condition. View full abstract»

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  • Transient behavior of current modulated 2-T inductively coupled plasma

    Publication Year: 2004 , Page(s): 39 - 46
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (360 KB) |  | HTML iconHTML  

    Time-dependent thermal plasmas are not in an equilibrium condition even if they are operated at a very high pressure. Therefore, nonequilibrium modeling is required in order to understand the underlying physics. Unfortunately, substantial modeling complexities have prevented significant advancements in the state-of-the-art. This paper presents new information for the nonequilibrium situation where the electron temperature is generally assumed to be higher than the heavy particle or gas temperature. Calculations are done for a radio-frequency inductively coupled thermal plasma where the coil current is pulse modulated. The discharge medium is argon at one atmosphere of pressure. The high-level current (representing the on-time state) is 170 A and is reduced to 80% of the high-level current or 136 A during the off-time state. The on-time and off-time durations are 10 and 5 ms, respectively. The electron temperature is observed to be higher by a factor of two or three compared to the gas temperature in the cooler region of the discharge. The difference between electron and heavy-particle temperature is negligible in the plasma core. The temporal behavior of the electron and heavy-particle temperatures are similar during the off-time, whereas the electron temperature's response is much faster than that of the heavy particle during the on-time. The response of the electron temperature to a step change in input power is almost instantaneous and enhances the energy exchange mechanism through elastic collisions between electron and heavy particles. View full abstract»

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  • Simulation of capacitively coupled single- and dual-frequency RF discharges

    Publication Year: 2004 , Page(s): 47 - 53
    Cited by:  Papers (44)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (296 KB) |  | HTML iconHTML  

    For a single-frequency capacitively coupled radio-frequency discharge, the detailed examination has been carried out of plasma density and sheath width, average potential profiles, ion-energy distribution at the electrodes and electron-energy distribution in the bulk plasma as a function of pressure, voltage, and frequency using particle-in-cell/Monte Carlo simulation. The results for Ar gas are presented. Scaling of plasma parameters with external parameters is determined. The characteristics of dual-frequency argon discharge are studied for different ratio of high/low frequencies. Nonmonotonous behavior of plasma density versus low-frequency voltages is attributed to the increase of sheath width and, as a consequence, to the increase of energy absorbed by ions in the sheath region. Subsequent decrease of energy absorbed by electrons results in the decrease of plasma density. For certain frequency ratio with the further increase of power, the plasma density increases again until the collapse of the bulk occurs. View full abstract»

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  • Experimental and simulation studies of new configuration of virtual cathode oscillator

    Publication Year: 2004 , Page(s): 54 - 59
    Cited by:  Papers (16)
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    A new configuration of a virtual cathode oscillator (VCO) has been studied for high-power microwave generation. In this VCO configuration, a resonant cavity is used to enhance the beam-field interaction in order to improve the microwave efficiency. Experiments were carried out on a repetitive pulsed power generator "ETIGO-IV" (400 kV, 13 kA, 120 ns, 1 Hz). The output microwaves are diagnosed for peak power and dominant mode by using horn antennas and E-field probes. The microwave frequency is obtained by fast-Fourier transformation of the signal recorded by a high-speed digital oscilloscope. The initial experimental results obtained by E-field probes have indicated a beam-to-microwave conversion efficiency of ∼10%. In addition, three-dimensional particle-in-cell simulations were carried out by using simulation code "MAGIC". Simulation results are compared with experimental results to examine the effect of the cavity and possible ways of further improvement of microwave efficiency. View full abstract»

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  • Low-voltage operation of Ka-band folded waveguide traveling-wave tube

    Publication Year: 2004 , Page(s): 60 - 66
    Cited by:  Papers (26)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (384 KB) |  | HTML iconHTML  

    Low-voltage operation of millimeter-wave folded waveguide traveling-wave tube (TWT) was investigated using a 12 kV linear electron beam. Backward wave oscillation operated at second space harmonic was observed with output power of 20 W, linear tunability of 6% within 0.01 dB/MHz, and voltage-frequency stability of 0.56 MHz/V. The measured frequency and output power are in a good agreement with the predicted values using a particle-in-cell (PIC) code. In addition, backward-wave interaction at second-space harmonic as an amplifier was observed with a measured linear gain of 15 dB and a bandwidth of 0.3%. For forward wave interaction, a linear gain of 25 dB, bandwidth of 17%, and efficiency of 7% were predicted for fundamental space harmonic using a PIC code. Improvement in efficiency was predicted for the forward-wave amplifier where it was operated as an oscillator employing a delayed feedback. Output power was increased by 10 dB in the delayed feedback oscillator comparing with the backward-wave oscillator. The effect of period doubling due to potential fabrication inaccuracies on the stopband was studied experimentally. The folded waveguide TWT fabricated using the Lighographie, Galvanoformung, Abformung (LIGA) process operated at much higher frequencies is discussed. View full abstract»

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  • 24-84-GHz gyrotron systems for technological microwave applications

    Publication Year: 2004 , Page(s): 67 - 72
    Cited by:  Papers (38)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (256 KB) |  | HTML iconHTML  

    During the last decade, a line of gyrotrons ranging in frequency from 24 to 84 GHz with the output power from 3 to 35 kW continuous wave, and a series of gyrotron-based systems have been developed by the Institute of Applied Physics, Nizhny Novgorod, Russia, jointly with GYCOM, Ltd., Nizhny Novgorod. Main technical characteristics of the gyrotrons, as well as the architecture of the gyrotron-based millimeter-wave power sources for applications are presented. The purposely developed transmission lines, applicators, and power control make gyrotron systems flexible and easily adaptable tools for research and development. A number of millimeter-wave technologies are extensively studied today using gyrotron systems; ceramics sintering and joining (including nanoceramics), functionally graded coatings, rapid annealing of semiconductors, microwave plasma assisted chemical vapor deposition, multiply charged ion production are among the most advanced development. View full abstract»

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  • Microwave innovation for industrial composite fabrication-the HEPHAISTOS technology

    Publication Year: 2004 , Page(s): 73 - 79
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (352 KB) |  | HTML iconHTML  

    A novel high-frequency processing technology has been developed for automated fabrication of high quality carbon-fiber-reinforced plastics. The development has been assisted by extensive numerical simulations. The use of microwaves shows new approaches for the process interaction for the fiber materials, precursors, resin systems, and layup preparation. Prepreg and injection technologies are completely supported and optimized. View full abstract»

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  • High-current heavy ion beams in the electrostatic plasma lens

    Publication Year: 2004 , Page(s): 80 - 83
    Cited by:  Papers (13)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (216 KB) |  | HTML iconHTML  

    We describe applications of the electrostatic plasma lens for manipulating and focusing moderate-energy, high-current, broad, heavy ion beams. Use of a plasma lens in this way has been successfully demonstrated in a series of experiments carried out collaboratively between the Institute of Physics, National Academy of Sciences, Kiev, Ukraine, and the Lawrence Berkeley National Laboratory, Berkeley, CA, in recent years. Here, we briefly review the plasma lens fundamentals, peculiarities of focusing heavy ion beams, and summarize some recent developments (experiments, computer simulations, theory). We show that there is a very narrow range of low magnetic field for which the optical properties of the lens improve markedly. This opens up some attractive possibilities for the development of a new-generation compact lens based on permanent magnets. Preliminary experimental results obtained at Kiev and Berkeley on the operation of a permanent magnet plasma lens for manipulating wide aperture high-current heavy ion beams are presented and summarized. View full abstract»

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  • Use of neural network to characterize a low pressure temperature effect on refractive property of silicon nitride film deposited by PECVD

    Publication Year: 2004 , Page(s): 84 - 89
    Cited by:  Papers (12)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (360 KB) |  | HTML iconHTML  

    Using a neural network, a refractive index (RI) of silicon nitride film was predicted as a function of process parameters, including radio frequency (RF) power, pressure, substrate temperature, and SiH4, NH3, and N2 flow rates. The film was deposited by a plasma-enhanced chemical vapor deposition (PECVD) system. The PECVD process was characterized by a 26-1 fractional factorial experiment. Particular emphasis was placed on examining temperature effects at low pressure. Model prediction accuracy was optimized as a function of training factors. Predicted parameter effects were experimentally validated. Plots generated from an optimized model were used to qualitatively estimate deposition mechanisms. It is noticeable that under various plasma conditions, the RI varied little with the temperature. The temperature effect was extremely sensitive to the pressure level. Enhanced ion bombardment at high temperatures yielded a Si-rich film. Effect of each gas was little affected by the temperature. The SiH4 flow rate played the most significant role in determining the RI at low pressure. View full abstract»

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  • Prediction of a radial variation of plasma structure and ion distributions in the wafer interface in two-frequency capacitively coupled plasma

    Publication Year: 2004 , Page(s): 90 - 100
    Cited by:  Papers (17)
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    Two-frequency capacitively coupled plasmas (2f-CCP) are widely used as one of the powerful tools for SiO2 etching. We numerically performed the design of SiO2 etching by using VicAddress. Radial variation of plasma structure and ion distributions having a direct influence on etching were investigated in a 2f-CCP in CF4(5%)/Ar, which consists both of a power source [very high frequency (VHF) 100 MHz] for high-density plasma production and a bias source (1 MHz) for the acceleration of ions toward the wafer. Degradation of the radial uniformity was observed near the wafer edge due to the distortion of surface potential mainly caused by the nonuniformity of electron flux at a wafer. Furthermore, we proposed a way of reducing the charge build-up inside the micro trench with the aid of negative charge injection by using a pulsed operation of VHF power source, especially at the low pressure condition. View full abstract»

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  • Development of a slot-excited planar microwave discharge device for uniform plasma processing

    Publication Year: 2004 , Page(s): 101 - 107
    Cited by:  Papers (8)
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    Planar microwave discharges using a multislotted planar antenna are investigated. A three-dimensional finite-difference time-domain code is developed for the calculation of wave propagation in nonuniform plasmas. The enhancement of the microwave fields near the plasma resonance is revealed in accordance with the theory of the resonant absorption. The global wave electric field is obtained for various excitation modes of the antenna. By operating the antenna with transverse electric mode, where the field is rotating in the azimuthal direction, and by minimizing the reflected power from the antenna, highly uniform overdense plasmas can be produced in a wide range of gas pressures and microwave powers. View full abstract»

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  • Anode melting from free-burning argon arcs

    Publication Year: 2004 , Page(s): 108 - 117
    Cited by:  Papers (24)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (648 KB) |  | HTML iconHTML  

    Predictions have been made of anode melting for free-burning arcs by making two-dimensional calculations of temperature profiles of the arc and the electrodes to make predictions of weld depth and weld shape in arc welding. Predicted properties at 150 A, for various arc lengths, are compared with experimental results of: 1) weld shape; 2) heat intensity as a function of radius; and 3) current density as a function of radius at the anode. The whole region of the arc system is modeled, including the tungsten cathode, the arc plasma and the solid and molten anode, including convection within the molten weld-pool. Theoretical and experimental results are also obtained for highand low-sulfur steel, which have markedly different surface tension properties of the molten liquid, resulting in weld depths that differ by a factor of three because of changed convective circulation properties in the weld pool. Although total power to the anode increases with increasing electrode separation, the current density becomes less, with the result that for electrode distances above 2 mm, for argon, the width and depth of the molten region become less, in agreement with experimental results that we have obtained. View full abstract»

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  • Predicted results of a HID DC current lamp considering a P-1 radiation model

    Publication Year: 2004 , Page(s): 118 - 126
    Cited by:  Papers (12)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (456 KB) |  | HTML iconHTML  

    This paper presents a numerical model that can be used for designing and/or improving a high-intensity DC discharge lamp. For purposes of illustration, we present results for the plasma subregion considering a 10 A discharge in a mercury-argon mixture (91:9 mass concentrations) operating at 1.1 atm. Calculation is carried out for a simple geometry of lamp, which consists of spherical vessel and ellipsoidal electrodes with a 15 mm interelectrode gap. The steady-state transport equations for mass, momentum, and energy, Laplace's equation for electrostatic potential, Ampere's law for magnetic field intensity, the species continuity equation, and the P-1 radiation equation are solved simultaneously for a simple two-dimensional axisymmetric geometry. The buoyancy effect is introduced and the lamp is placed vertically with the anode at the top. We have found a maximum plasma temperature of 10 000 K and a maximum velocity magnitude of 6 m/s near the cathode surface. The values of maximum temperature and velocity are also predicted to be relatively high near the anode surface compared to the values calculated around the middle of the interelectrode gap. View full abstract»

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  • Two-dimensional structure of PDP micro-discharge plasmas obtained using laser Thomson scattering

    Publication Year: 2004 , Page(s): 127 - 134
    Cited by:  Papers (16)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (376 KB) |  | HTML iconHTML  

    Laser Thomson scattering (LTS) has been applied for measurements of the electron density and electron temperature in micro-discharge plasmas for plasma-display panel research. A brief description of the method for overcoming the sparsity of scattered photons by the data accumulation technique is presented. Then, the technique of applying LTS to micro-discharge plasmas is described where the use of a specially designed triple-grating spectrometer has turned out to be essential. Improvements in the experimental setup to allow, for the first time, to collect laser LTS spectra at heights as close as to 60 μm from the electrode surface are discussed. Spatial distributions of the electron density and electron temperature in the vertical direction above the electrode surface are presented. Finally, an extension of the measurements into two-dimensions, namely along the electrode surface and at different heights above the electrodes enabling to cover the discharge front to be made, are presented and compared with the results of optical emission measurements. View full abstract»

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  • Recent results and modification program of JT-60 toward high integrated performance

    Publication Year: 2004 , Page(s): 135 - 143
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1008 KB) |  | HTML iconHTML  

    The first half of this paper briefly describes the major achievements of the existing JT-60U machine, i.e., high-performance plasma with full noninductive current drive, long time sustainment of high-beta plasma, and real-time neoclassical tearing modes (NTM) suppression experiments. In addition, the ongoing minor modification of the pulse length prolongation for further enhancement of numerous plasma properties is mentioned. The second half describes the major modification program for the next generation full superconducting coil tokamak called JT-60SC. The object of JT-60SC is to help in the design of DEMO reactor which will improve the attractiveness of fusion power plants from the economical and environmental viewpoints. The present status of the machine design and major technological developments are also presented. View full abstract»

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  • Progress in the 10-MW ECRH system for the Stellarator W7-X

    Publication Year: 2004 , Page(s): 144 - 151
    Cited by:  Papers (1)
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    During the last few years, electron-cyclotron resonance heating (ECRH) and electron-cyclotron current drive (ECCD) has proven to be one of the most attractive heating schemes for stellarators, as it provides net current free plasma start up and heating. Extensive measurements on stellarators at Garching provide a solid physical and technological basis for the ECRH system on the new stellarator facility W7-X, which is now under construction at the Max Planck Institute of Plasma Physics, Greifswald, Germany. The ECRH system will be built up from ten gyrotrons each with a power of 1 MW at a frequency of 140 GHz operating under almost stationary conditions (30 min.). The scientific goals of the superconducting stellarator and the demands for the ECRH system including the gyrotron development and the transmission lines are discussed. View full abstract»

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  • A high-density field reversed configuration plasma for magnetized target fusion

    Publication Year: 2004 , Page(s): 152 - 160
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (536 KB) |  | HTML iconHTML  

    We describe a program to demonstrate the scientific basis of magnetized target fusion (MTF). MTF is a potentially low-cost path to fusion which is intermediate in plasma regime between magnetic (MFE) and inertial fusion energy (IFE). MTF involves the compression of a magnetized target plasma and pressure times volume (PdV) heating to fusion relevant conditions inside a converging flux conserving boundary. We have chosen to demonstrate MTF by using a field-reversed configuration (FRC) as our magnetized target plasma and an imploding metal liner for compression. These choices take advantage of significant past scientific and technical accomplishments in MFE and defense programs research and should yield substantial plasma performance (nτ>1013 s-cm-3 T>5 keV) using an available pulsed-power implosion facility at modest cost. We have recently shown the density, temperature, and lifetime of this FRC to be within a factor of 2-3 of that required for use as a suitable target plasma for MTF compression for a fusion demonstration. View full abstract»

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  • Production of high-density plasmas with high harmonic fast waves in the GAMMA 10 tandem mirror

    Publication Year: 2004 , Page(s): 161 - 166
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    By using high harmonic fast waves (HHFW), the density clamping due to the formation of axial eigenmodes becomes weak in the GAMMA 10 tandem mirror. The excitation of HHFW is confirmed and the transition from the mode with a large axial wave number to the mode with a small wave number is detected. The production of high-energy ions as well as high-density plasmas is observed and the initial ion-temperature dependence of the higher harmonic damping is discussed. View full abstract»

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  • LHD diagnostics toward steady-state operation

    Publication Year: 2004 , Page(s): 167 - 176
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (616 KB)  

    The large helical device (LHD) is the world largest helical system having all superconducting coils. After completion of LHD in 1998, six experimental campaigns have been carried out successfully. The maximum stored energy, central electron temperature, and volume averaged beta value are 1.16 MJ, 10 keV, and 3.2%, respectively. The confinement time of the LHD plasma appears to be equivalent to that of tokamaks. One of the most important missions for LHD is to prove steady-state operation, which is also significant to international thermonuclear experimental reactor (ITER) and to future fusion reactors. LHD is quite appropriate for this purpose based upon the beneficial feature of a helical system, that is, no necessity of the plasma current. So far, the plasma discharge duration was achieved up to 150 s. The plasma density was kept constant by feedback control of gas puffing with real time information of the line density. The issue for demonstrating steady-state operation is whether divertor function to control particle and heat flux is effective enough. Relevant to this, LHD diagnostics should be consistent with the following: 1) continuous operation of main diagnostics during long-pulse operation for feedback control and physics understanding; 2) measurement of fraction of H, He, and impurities in the plasma; 3) heat removal and measure against possible damage or surface erosion of diagnostic components inside of the vacuum chamber; 4) data acquisition system for handling real time data display and a huge amount of data. Although there are already some achievements on the above subjects, there remain still several issues to be resolved. On the other hand, the long-pulse operation of the plasma gives benefits to the diagnostics. For example, the polarizing angle of ECE emission can be changed during the discharge, and the intensity dependence on the polarizing angle has been obtained. The spatial scanning of the neutral particle analyzer and the spectrometer can supply the spatial profiles of the fast neutral particle flux and the specific impurity lines. In this paper, the present status of these issues and future plans are described. View full abstract»

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IEEE Transactions on Plasma Sciences focuses on plasma science and engineering, including: magnetofluid dynamics and thermionics; plasma dynamics; gaseous electronics and arc technology.

 

 

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Editor-in-Chief
Steven J. Gitomer, Ph.D.
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