National Library of Energy BETA

Sample records for inductively coupled plasma

  1. Closed inductively coupled plasma cell

    DOE Patents [OSTI]

    Manning, T.J.; Palmer, B.A.; Hof, D.E.

    1990-11-06

    A closed inductively coupled plasma cell generates a relatively high power, low noise plasma for use in spectroscopic studies is disclosed. A variety of gases can be selected to form the plasma to minimize spectroscopic interference and to provide a electron density and temperature range for the sample to be analyzed. Grounded conductors are placed at the tube ends and axially displaced from the inductive coil, whereby the resulting electromagnetic field acts to elongate the plasma in the tube. Sample materials can be injected in the plasma to be excited for spectroscopy. 1 fig.

  2. Mobile inductively coupled plasma system

    DOE Patents [OSTI]

    D'Silva, Arthur P. (Ames, IA); Jaselskis, Edward J. (Ames, IA)

    1999-03-30

    A system for sampling and analyzing a material located at a hazardous site. A laser located remote from the hazardous site is connected to an optical fiber, which directs laser radiation proximate the material at the hazardous site. The laser radiation abates a sample of the material. An inductively coupled plasma is located remotely from the material. An aerosol transport system carries the ablated particles to a plasma, where they are dissociated, atomized and excited to provide characteristic optical reduction of the elemental constituents of the sample. An optical spectrometer is located remotely from the site. A second optical fiber is connected to the optical spectrometer at one end and the plasma source at the other end to carry the optical radiation from the plasma source to the spectrometer.

  3. Mobile inductively coupled plasma system

    DOE Patents [OSTI]

    D`Silva, A.P.; Jaselskis, E.J.

    1999-03-30

    A system is described for sampling and analyzing a material located at a hazardous site. A laser located remotely from the hazardous site is connected to an optical fiber, which directs laser radiation proximate the material at the hazardous site. The laser radiation abates a sample of the material. An inductively coupled plasma is located remotely from the material. An aerosol transport system carries the ablated particles to a plasma, where they are dissociated, atomized and excited to provide characteristic optical reduction of the elemental constituents of the sample. An optical spectrometer is located remotely from the site. A second optical fiber is connected to the optical spectrometer at one end and the plasma source at the other end to carry the optical radiation from the plasma source to the spectrometer. 10 figs.

  4. Improvements to Laser Ablation-Inductively Coupled Plasma-Mass...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    to Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry for Quantitative Analysis using Short Pulse UV Laser DESCRIPTION: Laser ablation inductively coupled plasma-mass...

  5. Inductively coupled plasma chemistry examinations with visible acousto-optic tunable filter hyperspectral imaging{

    E-Print Network [OSTI]

    Duffin, Kirk

    to be a powerful tool for plasma chemistry research. Introduction Inductively coupled plasma optical emission

  6. Inductively Coupled Plasma Etching of Bulk Titanium for MEMS Applications

    E-Print Network [OSTI]

    MacDonald, Noel C.

    Inductively Coupled Plasma Etching of Bulk Titanium for MEMS Applications E. R. Parker,a, * B. J for the bulk micromachining of microelectromechanical MEMS devices. Titanium- based MEMS have the potential for the microfabrication of titanium-based MEMS devices. © 2005 The Electrochemical Society. DOI: 10.1149/1.2006647 All

  7. Inductively coupled plasma torch with laminar flow cooling

    DOE Patents [OSTI]

    Rayson, Gary D. (Las Cruces, NM); Shen, Yang (Las Cruces, NM)

    1991-04-30

    An improved inductively coupled gas plasma torch. The torch includes inner and outer quartz sleeves and tubular insert snugly fitted between the sleeves. The insert includes outwardly opening longitudinal channels. Gas flowing through the channels of the insert emerges in a laminar flow along the inside surface of the outer sleeve, in the zone of plasma heating. The laminar flow cools the outer sleeve and enables the torch to operate at lower electrical power and gas consumption levels additionally, the laminar flow reduces noise levels in spectroscopic measurements of the gaseous plasma.

  8. Method of processing materials using an inductively coupled plasma

    DOE Patents [OSTI]

    Hull, D.E.; Bieniewski, T.M.

    1987-04-13

    A method of processing materials. The invention enables ultrafine, ultrapure powders to be formed from solid ingots in a gas free environment. A plasma is formed directly from an ingot which insures purity. The vaporized material is expanded through a nozzle and the resultant powder settles on a cold surface. An inductively coupled plasma may also be used to process waste chemicals. Noxious chemicals are directed through a series of plasma tubes, breaking molecular bonds and resulting in relatively harmless atomic constituents. 3 figs.

  9. A Parametric Study of Electron Extraction from a Low Frequency Inductively Coupled RF-Plasma Source

    E-Print Network [OSTI]

    the arc discharge. Consider instead a non-emitting plasma cathode in which the plasma is produced by rfA Parametric Study of Electron Extraction from a Low Frequency Inductively Coupled RF-Plasma Source and Nathaniel J. Fisch 3 Princeton University Plasma Physics Laboratory, Princeton, NJ 08540, USA Abstract

  10. Plasma dynamics in a discharge produced by a pulsed dual frequency inductively coupled plasma source

    SciTech Connect (OSTI)

    Mishra, Anurag; Lee, Sehan [Department of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon, Gyeonggi-do 440-746 (Korea, Republic of); Yeom, Geun Y., E-mail: gyyeom@skku.edu [Department of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon, Gyeonggi-do 440-746, South Korea and SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University, Suwon, Gyeonggi-do 440-746 (Korea, Republic of)

    2014-11-01

    Using a Langmuir probe, time resolved measurements of plasma parameters were carried out in a discharge produced by a pulsed dual frequency inductively coupled plasma source. The discharge was sustained in an argon gas environment at a pressure of 10 mTorr. The low frequency (P{sub 2} {sub MHz}) was pulsed at 1 kHz and a duty ratio of 50%, while high frequency (P{sub 13.56} {sub MHz}) was maintained in the CW mode. All measurements were carried out at the center of the discharge and 20?mm above the substrate. The results show that, at a particular condition (P{sub 2} {sub MHz}?=?200 W and P{sub 13.56} {sub MHz?}=?600 W), plasma density increases with time and stabilizes at up to ?200 ?s after the initiation of P{sub 2} {sub MHz} pulse at a plasma density of (2?×?10{sup 17} m{sup ?3}) for the remaining duration of pulse “on.” This stabilization time for plasma density increases with increasing P{sub 2} {sub MHz} and becomes ?300 ?s when P{sub 2} {sub MHz} is 600 W; however, the growth rate of plasma density is almost independent of P{sub 2} {sub MHz}. Interestingly, the plasma density sharply increases as the pulse is switched off and reaches a peak value in ?10 ?s, then decreases for the remaining pulse “off-time.” This phenomenon is thought to be due to the sheath modulation during the transition from “pulse on” to “pulse off” and partly due to RF noise during the transition period. The magnitude of peak plasma density in off time increases with increasing P{sub 2} {sub MHz}. The plasma potential and electron temperature decrease as the pulse develops and shows similar behavior to that of the plasma density when the pulse is switched off.

  11. Wave propagation and power deposition in magnetically enhanced inductively coupled and helicon plasma sources

    E-Print Network [OSTI]

    Kushner, Mark

    Wave propagation and power deposition in magnetically enhanced inductively coupled and helicon are increased, axial standing wave patterns occur with substantial power deposition downstream. The ability processing are of interest because of their ability to deposit power within the volume of the plasma beyond

  12. HIGH-ASPECT-RATIO INDUCTIVELY COUPLED PLASMA ETCHING OF BULK TITANIUM FOR MEMS APPLICATIONS

    E-Print Network [OSTI]

    MacDonald, Noel C.

    HIGH-ASPECT-RATIO INDUCTIVELY COUPLED PLASMA ETCHING OF BULK TITANIUM FOR MEMS APPLICATIONS E. R system for the bulk micromachining of MEMS devices. Titanium-based MEMS have the potential to be used for the microfabrication of titanium- based MEMS devices. INTRODUCTION Traditionally, microelectromechanical systems (MEMS

  13. A comprehensive study of different gases in inductively coupled plasma torch operating at one atmosphere

    SciTech Connect (OSTI)

    Punjabi, Sangeeta B.; Joshi, N. K.; Mangalvedekar, H. A.; Lande, B. K.; Das, A. K.; Kothari, D. C.

    2012-01-15

    A numerical study is done to understand the possible operating regimes of RF-ICP torch (3 MHz, 50 kW) using different gases for plasma formation at atmospheric pressure. A two dimensional numerical simulation of RF-ICP torch using argon, nitrogen, oxygen, and air as plasma gas has been investigated using computational fluid dynamic (CFD) software fluent{sup (c)}. The operating parameters varied here are central gas flow, sheath gas flow, RF-power dissipated in plasma, and plasma gas. The temperature contours, flow field, axial, and radial velocity profiles were investigated under different operating conditions. The plasma resistance, inductance of the torch, and the heat distribution for various plasma gases have also been investigated. The plasma impedance of ICP torch varies with different operating parameters and plays an important role for RF oscillator design and power coupling. These studies will be useful to decide the design criteria for ICP torches required for different material processing applications.

  14. Determination of trace impurities in uranium hexafluoride using inductively coupled plasma-atomic emission spectroscopy

    SciTech Connect (OSTI)

    Floyd, M.A.; Morrow, R.W.; Lazader, W.B.; Farrar, R.B.; Halouma, A.A.

    1982-06-01

    A procedure has been developed to determine 30 trace elements in high-purity uranium hexafluoride (UF/sub 6/) using inductively coupled plasma-atomic emission spectroscopy. The analytical method consists of a liquid-liquid extraction of the uranium from the trace impurities with a tri-(2-ethyl-hexyl)-phosphate (TEHP)-hexane mixture. A computer-controlled scanning monochromator system interfaced to an inductively coupled plasma (ICP) is then used to determine the levels of 30 trace elements present in the UF/sub 6/. A single sample dissolution procedure is used for all elements investigated. This preliminary report details experimental work done to date as part of a countinuing program to determine metallic impurities in uranium by ICP.

  15. Reduced electron temperature in a magnetized inductively-coupled plasma with internal coil

    SciTech Connect (OSTI)

    Arancibia Monreal, J.; Chabert, P. [LPP, CNRS, Ecole Polytechnique, UPMC, Paris XI, 91128 Palaiseau (France)] [LPP, CNRS, Ecole Polytechnique, UPMC, Paris XI, 91128 Palaiseau (France); Godyak, V. [RF Plasma Consulting, Brookline, Massachusetts 02446 (United States) [RF Plasma Consulting, Brookline, Massachusetts 02446 (United States); Michigan Institute for Plasma Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109 (United States)

    2013-10-15

    The effect of magnetic filtering on the electron energy distribution function is studied in an inductive discharge with internal coil coupling. The coil is placed inside the plasma and driven by a low-frequency power supply (5.8 MHz) which leads to a very high power transfer efficiency. A permanent dipole magnet may be placed inside the internal coil to produce a static magnetic field around 100 Gauss. The coil and the matching system are designed to minimize the capacitive coupling to the plasma. Capacitive coupling is quantified by measuring the radiofrequency (rf) plasma potential with a capacitive probe. Without the permanent magnet, the rf plasma potential is significantly smaller than the electron temperature. When the magnet is present, the rf plasma potential increases. The electron energy distribution function is measured as a function of space with and without the permanent magnet. When the magnet is present, electrons are cooled down to low temperature in the downstream region. This region of low electron temperature may be useful for plasma processing applications, as well as for efficient negative ion production.

  16. Synthesis of Ozone at Atmospheric Pressure by a Quenched Induction-Coupled Plasma Torch

    SciTech Connect (OSTI)

    A. Blutke; B.C. Stratton; D.R. Mikkelsen; J. Vavruska; R. Knight

    1998-01-01

    The technical feasibility of using an induction-coupled plasma (ICP) torch to synthesize ozone at atmospheric pressure is explored. Ozone concentrations up to ~250 ppm were produced using a thermal plasma reactor system based on an ICP torch operating at 2.5 MHz and ~11 kVA with an argon/oxygen mixture as the plasma-forming gas. A gaseous oxygen quench formed ozone by rapid mixing of molecular oxygen with atomic oxygen produced by the torch. The ozone concentration in the reaction chamber was measured by Fourier Transform infrared (FTIR) spectroscopy over a wide range of experimental configurations. The geometry of the quench gas flow, the quench flow velocity, and the quench flow rate played important roles in determining the ozone concentration. The ozone concentration was sensitive to the torch RF power, but was insensitive to the torch gas flow rates. These observations are interpreted within the framework of a simple model of ozone synthesis.

  17. Double layer formation in the expanding region of an inductively coupled electronegative plasma

    E-Print Network [OSTI]

    Plihon, N; Chabert, P

    2015-01-01

    Double-layers (DLs) were observed in the expanding region of an inductively coupled plasma with $\\text{Ar}/\\text{SF}\\_6$ gas mixtures. No DL was observed in pure argon or $\\text{SF}\\_6$ fractions below few percent. They exist over a wide range of power and pressure although they are only stable for a small window of electronegativity (typically between 8\\% and 13\\% of $\\text{SF}\\_6$ at 1mTorr), becoming unstable at higher electronegativity. They seem to be formed at the boundary between the source tube and the diffusion chamber and act as an internal boundary (the amplitude being roughly 1.5$\\frac{kT\\_e}{e}$)between a high electron density, high electron temperature, low electronegativity plasma upstream (in the source), and a low electron density, low electron temperature, high electronegativity plasma downstream.

  18. Determination of trace amounts of cerium in paint by inductively coupled plasma atomic emission spectrometry

    SciTech Connect (OSTI)

    Wong, K.L.

    1981-11-01

    The determination of Ce in paint by inductively coupled plasma atomic emission spectrometry (ICP-OES) is described, and the detection limit of ICP-OES of 0.0004 ppM is compared with that of other methods. The effects of the major elemental components of paint, Si, Pb, Cr, and Na on the ICP-OES determination of Ce were studied. The interference of 400 ppM of the other ions on the determination of 10 ppM Ce was small (0 to 3% error). The method is applicable to the range of 0.2 to 700 ppM Ce. (BLM)

  19. On the possibility of the multiple inductively coupled plasma and helicon plasma sources for large-area processes

    SciTech Connect (OSTI)

    Lee, Jin-Won; Lee, Yun-Seong Chang, Hong-Young; An, Sang-Hyuk

    2014-08-15

    In this study, we attempted to determine the possibility of multiple inductively coupled plasma (ICP) and helicon plasma sources for large-area processes. Experiments were performed with the one and two coils to measure plasma and electrical parameters, and a circuit simulation was performed to measure the current at each coil in the 2-coil experiment. Based on the result, we could determine the possibility of multiple ICP sources due to a direct change of impedance due to current and saturation of impedance due to the skin-depth effect. However, a helicon plasma source is difficult to adapt to the multiple sources due to the consistent change of real impedance due to mode transition and the low uniformity of the B-field confinement. As a result, it is expected that ICP can be adapted to multiple sources for large-area processes.

  20. Tin removal from extreme ultraviolet collector optics by inductively coupled plasma reactive ion etching

    SciTech Connect (OSTI)

    Shin, H.; Srivastava, S. N.; Ruzic, D. N. [Center for Plasma Material Interactions, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States)

    2008-05-15

    Tin (Sn) has the advantage of delivering higher conversion efficiency compared to other fuel materials (e.g., Xe or Li) in an extreme ultraviolet (EUV) source, a necessary component for the leading next generation lithography. However, the use of a condensable fuel in a lithography system leads to some additional challenges for maintaining a satisfactory lifetime of the collector optics. A critical issue leading to decreased mirror lifetime is the buildup of debris on the surface of the primary mirror that comes from the use of Sn in either gas discharge produced plasma (GDPP) or laser produced plasma (LPP). This leads to a decreased reflectivity from the added material thickness and increased surface roughness that contributes to scattering. Inductively coupled plasma reactive ion etching with halide ions is one potential solution to this problem. This article presents results for etch rate and selectivity of Sn over SiO{sub 2} and Ru. The Sn etch rate in a chlorine plasma is found to be much higher (of the order of hundreds of nm/min) than the etch rate of other materials. A thermally evaporated Sn on Ru sample was prepared and cleaned using an inductively coupled plasma etching method. Cleaning was confirmed using several material characterization techniques. Furthermore, a collector mock-up shell was then constructed and etching was performed on Sn samples prepared in a Sn EUV source using an optimized etching recipe. The sample surface before and after cleaning was analyzed by atomic force microscopy, x-ray photoelectron spectroscopy, and Auger electron spectroscopy. The results show the dependence of etch rate on the location of Sn samples placed on the collector mock-up shell.

  1. Electron kinetics and non-Joule heating in near-collisionless inductively coupled plasmas V. I. Kolobov

    E-Print Network [OSTI]

    Economou, Demetre J.

    of the key processes that deter- mine the power deposition and spatial uniformity of the plasma. Heating; colli- sional Joule heating predominates. Heating at low pres- sures is due to a combined effectElectron kinetics and non-Joule heating in near-collisionless inductively coupled plasmas V. I

  2. Low-frequency, self-sustained oscillations in inductively coupled plasmas used for optical pumping

    SciTech Connect (OSTI)

    Coffer, J.; Encalada, N.; Huang, M.; Camparo, J. [Physical Sciences Laboratories, The Aerospace Corporation 2310, E. El Segundo Blvd., El Segundo, California 90245 (United States)

    2014-10-28

    We have investigated very low frequency, on the order of one hertz, self-pulsing in alkali-metal inductively-coupled plasmas (i.e., rf-discharge lamps). This self-pulsing has the potential to significantly vary signal-to-noise ratios and (via the ac-Stark shift) resonant frequencies in optically pumped atomic clocks and magnetometers (e.g., the atomic clocks now flying on GPS and Galileo global navigation system satellites). The phenomenon arises from a nonlinear interaction between the atomic physics of radiation trapping and the plasma's electrical nature. To explain the effect, we have developed an evaporation/condensation theory (EC theory) of the self-pulsing phenomenon.

  3. E?H mode transition density and power in two types of inductively coupled plasma configuration

    SciTech Connect (OSTI)

    Wang, Jian; Du, Yin-chang; Zhang, Xiao; Zheng, Zhe; Liu, Yu; Xu, Liang; Wang, Pi; Cao, Jin-xiang, E-mail: jxcao@ustc.edu.cn [Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China)

    2014-07-15

    E???H transition power and density were investigated at various argon pressures in inductively coupled plasma (ICP) in a cylindrical interlaid chamber. The transition power versus the pressure shows a minimum transition power at 4?Pa (?/?=1) for argon. Then the transition density hardly changes at low pressures (?/??1), but it increases clearly when argon pressure exceeds an appropriate value. In addition, both the transition power and transition density are lower in the re-entrant configuration of ICP compared with that in the cylindrical configuration of ICP. The result may be caused from the decrease of stochastic heating in the re-entrant configuration of ICP. This work is useful to understand E???H mode transition and control the transition points in real plasma processes.

  4. Methods for detecting and correcting inaccurate results in inductively coupled plasma-atomic emission spectrometry

    DOE Patents [OSTI]

    Chan, George C. Y. (Bloomington, IN); Hieftje, Gary M. (Bloomington, IN)

    2010-08-03

    A method for detecting and correcting inaccurate results in inductively coupled plasma-atomic emission spectrometry (ICP-AES). ICP-AES analysis is performed across a plurality of selected locations in the plasma on an unknown sample, collecting the light intensity at one or more selected wavelengths of one or more sought-for analytes, creating a first dataset. The first dataset is then calibrated with a calibration dataset creating a calibrated first dataset curve. If the calibrated first dataset curve has a variability along the location within the plasma for a selected wavelength, errors are present. Plasma-related errors are then corrected by diluting the unknown sample and performing the same ICP-AES analysis on the diluted unknown sample creating a calibrated second dataset curve (accounting for the dilution) for the one or more sought-for analytes. The cross-over point of the calibrated dataset curves yields the corrected value (free from plasma related errors) for each sought-for analyte.

  5. Standard test method for isotopic abundance analysis of uranium hexa?uoride and uranyl nitrate solutions by multi-collector, inductively coupled plasma-mass spectrometry

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    2008-01-01

    Standard test method for isotopic abundance analysis of uranium hexa?uoride and uranyl nitrate solutions by multi-collector, inductively coupled plasma-mass spectrometry

  6. Mode transition in CF{sub 4} + Ar inductively coupled plasma

    SciTech Connect (OSTI)

    Liu, Wei; Gao, Fei; Zhao, Shu-Xia; Li, Xue-Chun; Wang, You-Nian [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)] [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)

    2013-12-15

    The E to H mode transitions are studied by a hairpin probe and optical emission spectroscopy in inductively coupled CF{sub 4} + Ar plasmas. Electron density, optical emission intensity of Ar, and the voltage and current are measured during the E to H mode transitions. It is found that the electron density and plasma emission intensity increase continuously at low pressure during the E to H mode transition, while they jump up discontinuously at high pressure. Meanwhile, the transition threshold power and ?P (the power interval between E and H mode) increase by increasing the pressure. When the ratio of CF{sub 4} increases, the E to H mode transition happens at higher applied power, and meanwhile, the ?P also significantly increases. Besides, the effects of CF{sub 4} gas ratio on the plasma properties and the circuit electrical properties in both pure E and H modes were also investigated. The electron density and plasma emission intensity both decrease upon increasing the ratio of CF{sub 4} at the two modes, due to the stronger electrons loss scheme. The applied voltages at E and H modes both increase as increasing the CF{sub 4} gas ratio, however the applied current at two modes behave just oppositely with the gas ratio.

  7. Fluid simulations of frequency effects on nonlinear harmonics in inductively coupled plasma

    SciTech Connect (OSTI)

    Si Xuejiao; Xu Xiang; Wang Younian [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Zhao Shuxia [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Department of Chemistry, University of Antwerp, Campus Drie Eiken, Universiteitsplein 1, BE-2610 Wilrijk-Antwerp (Belgium); Bogaerts, A. [Department of Chemistry, University of Antwerp, Campus Drie Eiken, Universiteitsplein 1, BE-2610 Wilrijk-Antwerp (Belgium)

    2011-03-15

    A fluid model is self-consistently established to investigate the harmonic effects in an inductively coupled plasma, where the electromagnetic field is solved by the finite difference time domain technique. The spatiotemporal distribution of harmonic current density, harmonic potential, and other plasma quantities, such as radio frequency power deposition, plasma density, and electron temperature, have been investigated. Distinct differences in current density have been observed when calculated with and without Lorentz force, which indicates that the nonlinear Lorentz force plays an important role in the harmonic effects, especially at low frequencies. Moreover, the even harmonics are larger than the odd harmonics both in the current density and the potential. Finally, the dependence of various plasma quantities with and without the Lorentz force on various driving frequencies is also examined. It is shown that the deposited power density decreases and the depth of penetration increases slightly because of the Lorentz force. The electron density increases distinctly while the electron temperature remains almost the same when the Lorentz force is taken into account.

  8. Inductively Coupled Plasma: Fundamental Particle Investigations with Laser Ablation and Applications in Magnetic Sector Mass Spectrometry

    SciTech Connect (OSTI)

    Nathan Joe Saetveit

    2008-08-18

    Particle size effects and elemental fractionation in laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) are investigated with nanosecond and femtosecond laser ablation, differential mobility analysis, and magnetic sector ICP-MS. Laser pulse width was found to have a significant influence on the LA particle size distribution and the elemental composition of the aerosol and thus fractionation. Emission from individual particles from solution nebulization, glass, and a pressed powder pellet are observed with high speed digital photography. The presence of intact particles in an ICP is shown to be a likely source of fractionation. A technique for the online detection of stimulated elemental release from neural tissue using magnetic sector ICP-MS is described. Detection limits of 1 {micro}g L{sup -1} or better were found for P, Mn, Fe, Cu, and Zn in a 60 {micro}L injection in a physiological saline matrix.

  9. Atlas of Atomic Spectral Lines of Neptunium Emitted by Inductively Coupled Plasma

    SciTech Connect (OSTI)

    DeKalb, E.L. and Edelson, M. C.

    1987-08-01

    Optical emission spectra from high-purity Np-237 were generated with a glovebox-enclosed inductively coupled plasma (ICP) source. Spectra covering the 230-700 nm wavelength range are presented along with general commentary on the methodology used in collecting the data. The Ames Laboratory Nuclear Safeguards and Security Program has been charged with the task of developing optical spectroscopic methods to analyze the composition of spent nuclear fuels. Such materials are highly radioactive even after prolonged 'cooling' and are chemically complex. Neptunium (Np) is a highly toxic by-product of nuclear power generation and is found, in low abundance, in spent nuclear fuels. This atlas of the optical emission spectrum of Np, as produced by an inductively coupled plasma (ICP) spectroscopic source, is part of a general survey of the ICP emission spectra of the actinide elements. The ICP emission spectrum of the actinides originates almost exclusively from the electronic relaxation of excited, singly ionized species. Spectral data on the Np ion emission spectrum (i.e., the Np II spectrum) have been reported by Tomkins and Fred [1] and Haaland [2]. Tomkins and Fred excited the Np II spectrum with a Cu spark discharge and identified 114 Np lines in the 265.5 - 436.3 nm spectral range. Haaland, who corrected some spectral line misidentifications in the work of Tomkins and Fred, utilized an enclosed Au spark discharge to excite the Np II spectrum and reported 203 Np lines within the 265.4 - 461.0 nm wavelength range.

  10. COMPARISON OF LEAD CONCENTRATION IN SURFACE SOIL BY INDUCTED COUPLED PLASMA/OPTICAL EMISSION SPECTROMETRY AND X-RAY FLUORESCENCE

    E-Print Network [OSTI]

    Boyer, Edmond

    COMPARISON OF LEAD CONCENTRATION IN SURFACE SOIL BY INDUCTED COUPLED PLASMA/OPTICAL EMISSION-en-Halatte, France roseline.bonnard@ineris.fr) Keywords : soil lead concentration, soil samples, in situ measurements, X-ray fluorescence, ICP/OES ABSTRACT The lead concentration in the surface soil of a French village

  11. Separation Of Uranium And Plutonium Isotopes For Measurement By Multi Collector Inductively Coupled Plasma Mass Spectroscopy

    SciTech Connect (OSTI)

    Martinelli, R E; Hamilton, T F; Williams, R W; Kehl, S R

    2009-03-29

    Uranium (U) and plutonium (Pu) isotopes in coral soils, contaminated by nuclear weapons testing in the northern Marshall Islands, were isolated by ion-exchange chromatography and analyzed by mass spectrometry. The soil samples were spiked with {sup 233}U and {sup 242}Pu tracers, dissolved in minerals acids, and U and Pu isotopes isolated and purified on commercially available ion-exchange columns. The ion-exchange technique employed a TEVA{reg_sign} column coupled to a UTEVA{reg_sign} column. U and Pu isotope fractions were then further isolated using separate elution schemes, and the purified fractions containing U and Pu isotopes analyzed sequentially using multi-collector inductively coupled plasma mass spectrometer (MCICP-MS). High precision measurements of {sup 234}U/{sup 235}U, {sup 238}U/{sup 235}U, {sup 236}U/{sup 235}U, and {sup 240}Pu/{sup 239}Pu in soil samples were attained using the described methodology and instrumentation, and provide a basis for conducting more detailed assessments of the behavior and transfer of uranium and plutonium in the environment.

  12. Laser-ablation sampling for inductively coupled plasma distance-of-flight mass spectrometry

    SciTech Connect (OSTI)

    Gundlach-Graham, Alexander W.; Dennis, Elise; Ray, Steven J.; Enke, Christie G.; Barinaga, Charles J.; Koppenaal, David W.; Hieftje, Gary M.

    2015-01-01

    An inductively coupled plasma distance-of-flight mass spectrometer (ICP-DOFMS) has been coupled with laser-ablation (LA) sample introduction for the elemental analysis of solids. ICP-DOFMS is well suited for the analysis of laser-generated aerosols because it offers both high-speed mass analysis and simultaneous multi-elemental detection. Here, we evaluate the analytical performance of the LA-ICP-DOFMS instrument, equipped with a microchannel plate-based imaging detector, for the measurement of steady-state LA signals, as well as transient signals produced from single LA events. Steady-state detection limits are 1 mg g1, and absolute single-pulse LA detection limits are 200 fg for uranium; the system is shown capable of performing time-resolved single-pulse LA analysis. By leveraging the benefits of simultaneous multi-elemental detection, we also attain a good shot-to-shot reproducibility of 6% relative standard deviation (RSD) and isotope-ratio precision of 0.3% RSD with a 10 s integration time.

  13. Fundamental and methodological investigations for the improvement of elemental analysis by inductively coupled plasma mass soectrometry

    SciTech Connect (OSTI)

    Ebert, Christopher Hysjulien [Ames Laboratory

    2012-07-27

    This dissertation describes a variety of studies meant to improve the analytical performance of inductively coupled plasma mass spectrometry (ICP-MS) and laser ablation (LA) ICP-MS. The emission behavior of individual droplets and LA generated particles in an ICP is studied using a high-speed, high frame rate digital camera. Phenomena are observed during the ablation of silicate glass that would cause elemental fractionation during analysis by ICP-MS. Preliminary work for ICP torch developments specifically tailored for the improvement of LA sample introduction are presented. An abnormal scarcity of metal-argon polyatomic ions (MAr{sup +}) is observed during ICP-MS analysis. Evidence shows that MAr{sup +} ions are dissociated by collisions with background gas in a shockwave near the tip of the skimmer cone. Method development towards the improvement of LA-ICP-MS for environmental monitoring is described. A method is developed to trap small particles in a collodion matrix and analyze each particle individually by LA-ICP-MS.

  14. Effectiveness of electron-cyclotron and transmission resonance heating in inductively coupled plasmas

    E-Print Network [OSTI]

    Economou, Demetre J.

    Effectiveness of electron-cyclotron and transmission resonance heating in inductively coupled October 2005 The electron-cyclotron and transmission resonances in magnetically enhanced low-pressure one-cyclotron and transmission resonances, but normally does not exhibit a sharp peak at the electron-cyclotron resonance ECR

  15. A study on the maximum power transfer condition in an inductively coupled plasma using transformer circuit model

    SciTech Connect (OSTI)

    Kim, Young-Do; Lee, Hyo-Chang; Chung, Chin-Wook [Department of Electrical Engineering, Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791 (Korea, Republic of)] [Department of Electrical Engineering, Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791 (Korea, Republic of)

    2013-09-15

    Correlations between the external discharge parameters (the driving frequency ? and the chamber dimension R) and plasma characteristics (the skin depth ? and the electron-neutral collision frequency ?{sub m}) are studied using the transformer circuit model [R. B. Piejak et al., Plasma Sources Sci. Technol. 1, 179 (1992)] when the absorbed power is maximized in an inductively coupled plasma. From the analysis of the transformer circuit model, the maximum power transfer conditions, which depend on the external discharge parameters and the internal plasma characteristics, were obtained. It was found that a maximum power transfer occurs when ??0.38R for the discharge condition at which ?{sub m}/??1, while it occurs when ???(2)?(?/?{sub m})R for the discharge condition at which ?{sub m}/??1. The results of this circuit analysis are consistent with the stable last inductive mode region of an inductive-to-capacitive mode transition [Lee and Chung, Phys. Plasmas 13, 063510 (2006)], which was theoretically derived from Maxwell's equations. Our results were also in agreement with the experimental results. From this work, we demonstrate that a simple circuit analysis can be applied to explain complex physical phenomena to a certain extent.

  16. Multi-Collector Inductively Coupled Plasma Mass Spectrometer – Operational Performance Report

    SciTech Connect (OSTI)

    Matthew Watrous; Anthony Appelhans; Robert Hague; John Olson; Tracy Houghton

    2013-06-01

    The INL made an assessment of the commercially available inductively coupled plasma mass spectrometers (ICPMS) for actinide analysis; emphasizing low detection limits for plutonium. INL scientists subsequently determined if plutonium was present on a swipe, at a 10 million atom decision level. This report describes the evaluation of ICPMS instruments and the operational testing of a new process for the dissolution, separation and analysis via ICPMS of swipes for plutonium and uranium. The swipe dissolution, plutonium and uranium isolation, separation and purification are wet chemistry methods following established procedures. The ICPMS is a commercially available multi-collector magnetic sector mass spectrometer that utilizes five ion counting detectors operating simultaneously. The instrument includes a sample introduction system allowing for sample volumes of < 1 mL to be reproducibly injected into the instrument with minimal waste of the sample solution, while maximizing the useable signal. The performance of the instrument was measured using SRM 996 (244Pu spike) at concentrations of 12 parts per quadrillion (ppq, fg/mL) and with SRM 4350B Columbia River Sediment samples spiked onto swipes at the 10 million atom level. The measured limit of detection (LOD, defined as 3s) for 239Pu is 310,000 atoms based upon the instrument blank data. The limit of quantification (LOQ defined as 10 s) for 239Pu is 105,000 atoms. The measured limit of detection for 239Pu from the SRM 4350B spiked onto a swipe was 2.7 million atoms with the limit of quantification being 9.0 million atoms.

  17. Investigations into the origins of polyatomic ions in inductively coupled plasma-mass spectrometry

    SciTech Connect (OSTI)

    McIntyre, Sally M.

    2010-05-16

    An inductively coupled plasma-mass spectrometer (ICP-MS) is an elemental analytical instrument capable of determining nearly all elements in the periodic table at limits of detection in the parts per quadrillion and with a linear analytical range over 8-10 orders of magnitude. Three concentric quartz tubes make up the plasma torch. Argon gas is spiraled through the outer tube and generates the plasma powered by a looped load coil operating at 27.1 or 40.6 MHz. The argon flow of the middle channel is used to keep the plasma above the innermost tube through which solid or aqueous sample is carried in a third argon stream. A sample is progressively desolvated, atomized and ionized. The torch is operated at atmospheric pressure. To reach the reduced pressures of mass spectrometers, ions are extracted through a series of two, approximately one millimeter wide, circular apertures set in water cooled metal cones. The space between the cones is evacuated to approximately one torr. The space behind the second cone is pumped down to, or near to, the pressure needed for the mass spectrometer (MS). The first cone, called the sampler, is placed directly in the plasma plume and its position is adjusted to the point where atomic ions are most abundant. The hot plasma gas expands through the sampler orifice and in this expansion is placed the second cone, called the skimmer. After the skimmer traditional MS designs are employed, i.e. quadrupoles, magnetic sectors, time-of-flight. ICP-MS is the leading trace element analysis technique. One of its weaknesses are polyatomic ions. This dissertation has added to the fundamental understanding of some of these polyatomic ions, their origins and behavior. Although mainly continuing the work of others, certain novel approaches have been introduced here. Chapter 2 includes the first reported efforts to include high temperature corrections to the partition functions of the polyatomic ions in ICP-MS. This and other objections to preceeding papers in this area were addressed. Errors in the measured T{sub gas} values were found for given errors in the experimental and spectroscopic values. The ionization energy of the neutral polyatomic ion was included in calculations to prove the validity of ignoring more complicated equilibria. Work was begun on the question of agreement between kinetics of the plasma and interface and the increase and depletion seen in certain polyatomic ions. This dissertation was also the first to report day to day ranges for T{sub gas} values and to use a statistical test to compare different operating conditions. This will help guide comparisons of previous and future work. Chapter 4 was the first attempt to include the excited electronic state 2 in the partition function of ArO{sup +} as well as the first to address the different dissociation products of the ground and first electronic levels of ArO{sup +}. Chapter 5 reports an interesting source of memory in ICP-MS that could affect mathematical corrections for polyatomic ions. For future work on these topics I suggest the following experiments and investigations. Clearly not an extensive list, they are instead the first topics curiosity brings to mind. (1) Measurement of T{sub gas} values when using the flow injection technique of Appendix B. It was believed that there was a fundamental difference in the plasma when the auto-sampler was used versus a continuous injection. Is this reflected in T{sub gas} values? (2) The work of Chapter 3 can be expanded and supplemented with more trials, new cone materials (i.e. copper, stainless steel) and more cone geometries. Some of this equipment is already present in the laboratory, others could be purchased or made. (3) T{sub gas} values from Chapter 3 could be correlated with instrument pressures during the experiment. Pressures after the skimmer cone were recorded for many days but have yet to be collated with the measured T{sub gas} values. (4) The work in Chapter 5 could be expanded to include more metals. Does the curious correlation between measured T{sub gas} and element boili

  18. Halftoning band gap of InAs/InP quantum dots using inductively coupled argon plasma-enhanced intermixing

    SciTech Connect (OSTI)

    Nie, D.; Mei, T.; Xu, C. D.; Dong, J. R.

    2006-09-25

    Inductively coupled argon plasma-enhanced intermixing of InAs/InP quantum dots grown on InP substrate is investigated. Intermixing is promoted by the near-surface defects generated by plasma exposure in annealing at a temperature of 600 deg. C for 30 s. The annealing results in a maximum differential band-gap blueshift of 106 nm but a thermal shift of only 10 nm. Band-gap halftones are obtained by controlling the amount of near-surface defects via wet chemical etching on the plasma-exposed InP cap layer. No degradation of quantum-dot crystal quality due to the process has been observed as evidenced by photoluminescence intensity.

  19. Online tuning of impedance matching circuit for long pulse inductively coupled plasma source operation—An alternate approach

    SciTech Connect (OSTI)

    Sudhir, Dass; Bandyopadhyay, M. Chakraborty, A.; Kraus, W.; Gahlaut, A.; Bansal, G.

    2014-01-15

    Impedance matching circuit between radio frequency (RF) generator and the plasma load, placed between them, determines the RF power transfer from RF generator to the plasma load. The impedance of plasma load depends on the plasma parameters through skin depth and plasma conductivity or resistivity. Therefore, for long pulse operation of inductively coupled plasmas, particularly for high power (?100 kW or more) where plasma load condition may vary due to different reasons (e.g., pressure, power, and thermal), online tuning of impedance matching circuit is necessary through feedback. In fusion grade ion source operation, such online methodology through feedback is not present but offline remote tuning by adjusting the matching circuit capacitors and tuning the driving frequency of the RF generator between the ion source operation pulses is envisaged. The present model is an approach for remote impedance tuning methodology for long pulse operation and corresponding online impedance matching algorithm based on RF coil antenna current measurement or coil antenna calorimetric measurement may be useful in this regard.

  20. VOLUME 86, NUMBER 24 P H Y S I C A L R E V I E W L E T T E R S 11 JUNE 2001 Nonlocal Power Deposition in Inductively Coupled Plasmas

    E-Print Network [OSTI]

    Chen, Francis F.

    Deposition in Inductively Coupled Plasmas John D. Evans* and Francis F. Chen Electrical Engineering fields in an overdense plasma. This problem has resur- faced with the use of inductively coupled plasmas,10­17]. The extensive, ongoing work by Godyak, Piejak, and others [4,11­15] is done with a spiral "stove-top" antenna

  1. Non-invasive in situ plasma monitoring of reactive gases using the floating harmonic method for inductively coupled plasma etching application

    SciTech Connect (OSTI)

    Lee, J. H.; Kim, M. J.; Yoon, Y. S.

    2013-04-15

    The floating harmonic method was developed for in situ plasma diagnostics of allowing real time measurement of electron temperature (T{sub e}) and ion flux (J{sub ion}) without contamination of the probe from surface modification by reactive species. In this study, this novel non-invasive diagnostic system was studied to characterize inductively coupled plasma of reactive gases monitoring T{sub e} and J{sub ion} for investigating the optimum plasma etching conditions and controlling of the real-time plasma surface reaction in the range of 200-900 W source power, 10-100 W bias power, and 3-15 mTorr chamber pressure, respectively.

  2. Etching kinetics and surface roughening of polysilicon and dielectric materials in inductively coupled plasma beams

    E-Print Network [OSTI]

    Yin, Yunpeng, Ph. D. Massachusetts Institute of Technology

    2007-01-01

    Plasma etching processes often roughen the feature sidewalls forming anisotropic striations. A clear understanding of the origin and control of sidewall roughening is extremely desirable, particularly at the gate level ...

  3. Optical emission spectroscopy and Langmuir probe diagnostics of CH{sub 3}F/O{sub 2} inductively coupled plasmas

    SciTech Connect (OSTI)

    Karakas, Erdinc; Donnelly, Vincent M.; Economou, Demetre J. [Plasma Processing Laboratory, Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas 77204-4004 (United States)] [Plasma Processing Laboratory, Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas 77204-4004 (United States)

    2013-06-07

    A CH{sub 3}F:O{sub 2} (50%:50%) inductively coupled discharge, sustained in a compact plasma reactor, was investigated as a function of power (20-400 W) and pressure (9-30 mTorr), using optical emission spectroscopy and Langmuir probe measurements. The electron density increased linearly with power but only weakly with pressure. The effective electron temperature was nearly independent of power and pressure. The gas temperature, obtained from the rotational structure of N{sub 2} (C {yields} B) optical emission, increased from 400 to 900 K as a function of inductive mode power between 75 and 400 W at 10 mTorr. For constant feed gas flow, the absolute H, F, and O atom densities, estimated by optical emission rare gas actinometry, increased linearly with power. The absolute number density ratios H/Ar, F/Ar, and O/Ar, increased, decreased, and remained constant, respectively, with pressure. The H-atom density was estimated to be 5.4 Multiplication-Sign 10{sup 13} cm{sup -3} at 400 W and 10 mTorr (gas temperature = 900 K), implying a high degree of dissociation of the CH{sub 3}F feedstock gas. The F and O atom number densities were much lower (8.3 Multiplication-Sign 10{sup 12} cm{sup -3} and 5.9 Multiplication-Sign 10{sup 12} cm{sup -3}, respectively) for the same conditions, suggesting that most of the fluorine and oxygen is contained in reaction products HF, CO, CO{sub 2}, H{sub 2}O, and OH. The relative number densities of HF, CO, and CO{sub 2} were observed to first rapidly increase with power, and then reach a plateau or decay slightly at higher power. Reaction mechanisms were proposed to explain the observed behavior of the number density of F and HF vs. power and pressure.

  4. Determination of total chlorine and bromine in solid wastes by sintering and inductively coupled plasma-sector field mass spectrometry

    SciTech Connect (OSTI)

    Osterlund, Helene Rodushkin, Ilia; Ylinenjaervi, Karin; Baxter, Douglas C.

    2009-04-15

    A sample preparation method based on sintering, followed by analysis by inductively coupled plasma-sector field mass spectrometry (ICP-SFMS) for the simultaneous determination of chloride and bromide in diverse and mixed solid wastes, has been evaluated. Samples and reference materials of known composition were mixed with a sintering agent containing Na{sub 2}CO{sub 3} and ZnO and placed in an oven at 560 deg. C for 1 h. After cooling, the residues were leached with water prior to a cation-exchange assisted clean-up. Alternatively, a simple microwave-assisted digestion using only nitric acid was applied for comparison. Thereafter the samples were prepared for quantitative analysis by ICP-SFMS. The sintering method was evaluated by analysis of certified reference materials (CRMs) and by comparison with US EPA Method 5050 and ion chromatography with good agreement. Median RSDs for the sintering method were determined to 10% for both chlorine and bromine, and median recovery to 96% and 97%, respectively. Limits of detection (LODs) were 200 mg/kg for chlorine and 20 mg/kg for bromine. It was concluded that the sintering method is suitable for chlorine and bromine determination in several matrices like sewage sludge, plastics, and edible waste, as well as for waste mixtures. The sintering method was also applied for determination of other elements present in anionic forms, such as sulfur, arsenic, selenium and iodine.

  5. DETERMINATION OF 237NP AND PU ISOTOPES IN LARGE SOIL SAMPLES BY INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY

    SciTech Connect (OSTI)

    Maxwell, S.

    2010-07-26

    A new method for the determination of {sup 237}Np and Pu isotopes in large soil samples has been developed that provides enhanced uranium removal to facilitate assay by inductively coupled plasma mass spectrometry (ICP-MS). This method allows rapid preconcentration and separation of plutonium and neptunium in large soil samples for the measurement of {sup 237}Np and Pu isotopes by ICP-MS. {sup 238}U can interfere with {sup 239}Pu measurement by ICP-MS as {sup 238}UH{sup +} mass overlap and {sup 237}Np via {sup 238}U peak tailing. The method provides enhanced removal of uranium by separating Pu and Np initially on TEVA Resin, then transferring Pu to DGA resin for additional purification. The decontamination factor for removal of uranium from plutonium for this method is greater than 1 x 10{sup 6}. Alpha spectrometry can also be applied so that the shorter-lived {sup 238}Pu isotope can be measured successfully. {sup 239}Pu, {sup 242}Pu and {sup 237}Np were measured by ICP-MS, while {sup 236}Pu and {sup 238}Pu were measured by alpha spectrometry.

  6. Standard test method for determination of impurities in nuclear grade uranium compounds by inductively coupled plasma mass spectrometry

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 This test method covers the determination of 67 elements in uranium dioxide samples and nuclear grade uranium compounds and solutions without matrix separation by inductively coupled plasma mass spectrometry (ICP-MS). The elements are listed in Table 1. These elements can also be determined in uranyl nitrate hexahydrate (UNH), uranium hexafluoride (UF6), triuranium octoxide (U3O8) and uranium trioxide (UO3) if these compounds are treated and converted to the same uranium concentration solution. 1.2 The elements boron, sodium, silicon, phosphorus, potassium, calcium and iron can be determined using different techniques. The analyst's instrumentation will determine which procedure is chosen for the analysis. 1.3 The test method for technetium-99 is given in Annex A1. 1.4 The values stated in SI units are to be regarded as standard. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish ...

  7. First inductively coupled plasma-distance-of-flight mass spectrometer: instrument performance with a microchannel plate/phosphor imaging detector

    SciTech Connect (OSTI)

    Gundlach-Graham, Alexander W.; Dennis, Elise; Ray, Steven J.; Enke, Christie G.; Barinaga, Charles J.; Koppenaal, David W.; Hieftje, Gary M.

    2013-09-01

    Here we describe the first combination of a Distance-of-Flight Mass Spectrometry (DOFMS) instrument and an inductively coupled plasma (ICP) ion source. DOFMS is a velocity-based MS technique in which ions of a range of mass-to-charge (m/z) values are detected simultaneously along the length of a spatially selective detector. As a relative of time-of-flight (TOF) MS, DOFMS leverages benefits fromboth TOFMS and spatially dispersive MS. The simultaneous detection of groups of m/z values improves dynamic range by spreading ion signal across many detector elements and reduces correlated noise by signal ratioing. To ascertain the performance characteristics of the ICP-DOFMS instrument, we have employed a microchannel-plate/phosphor detection assembly with a scientific CCD to capture images of the phosphor plate. With this simple (and commercially available) detection scheme, elemental detection limits from 2–30 ng L*1 and a linear dynamic range of 5 orders of magnitude (10–106 ng L1) have been demonstrated. Additionally, a competitive isotope-ratio precision of 0.1% RSD has been achieved with only a 6 s signal integration period. In addition to first figures of merit, this paper outlines technical considerations for the design of the ICP-DOFMS.

  8. Standard practice for analysis of aqueous leachates from nuclear waste materials using inductively coupled plasma-atomic emission spectrometry

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 This practice is applicable to the determination of low concentration and trace elements in aqueous leachate solutions produced by the leaching of nuclear waste materials, using inductively coupled plasma-atomic emission spectroscopy (ICP-AES). 1.2 The nuclear waste material may be a simulated (non-radioactive) solid waste form or an actual solid radioactive waste material. 1.3 The leachate may be deionized water or any natural or simulated leachate solution containing less than 1 % total dissolved solids. 1.4 This practice should be used by analysts experienced in the use of ICP-AES, the interpretation of spectral and non-spectral interferences, and procedures for their correction. 1.5 No detailed operating instructions are provided because of differences among various makes and models of suitable ICP-AES instruments. Instead, the analyst shall follow the instructions provided by the manufacturer of the particular instrument. This test method does not address comparative accuracy of different devices...

  9. RAPID DETERMINATION OF 237 NP AND PU ISOTOPES IN WATER BY INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY AND ALPHA SPECTROMETRY

    SciTech Connect (OSTI)

    Maxwell, S.; Jones, V.; Culligan, B.; Nichols, S.; Noyes, G.

    2010-06-23

    A new method that allows rapid preconcentration and separation of plutonium and neptunium in water samples was developed for the measurement of {sup 237}Np and Pu isotopes by inductively-coupled plasma mass spectrometry (ICP-MS) and alpha spectrometry; a hybrid approach. {sup 238}U can interfere with {sup 239}Pu measurement by ICP-MS as {sup 238}UH{sup +} mass overlap and {sup 237}Np via peak tailing. The method provide enhanced removal of uranium by separating Pu and Np initially on TEVA Resin, then moving Pu to DGA resin for additional removal of uranium. The decontamination factor for uranium from Pu is almost 100,000 and the decontamination factor for U from Np is greater than 10,000. This method uses stacked extraction chromatography cartridges and vacuum box technology to facilitate rapid separations. Preconcentration is performed using a streamlined calcium phosphate precipitation method. Purified solutions are split between ICP-MS and alpha spectrometry so that long and short-lived Pu isotopes can be measured successfully. The method allows for simultaneous extraction of 20 samples (including QC samples) in 4 to 6 hours, and can also be used for emergency response. {sup 239}Pu, {sup 242}Pu and {sup 237}Np were measured by ICP-MS, while {sup 236}Pu, {sup 238}Pu, and {sup 239}Pu were measured by alpha spectrometry.

  10. Structural Study of SiC Nanoparticles Grown by Inductively Coupled Plasma and Laser Pyrolysis for Nano-structured Ceramics Elaboration

    SciTech Connect (OSTI)

    Leconte, Yann; Portier, Xavier; Herlin-Boime, Nathalie; Reynaud, Cecile

    2008-07-01

    Refractory carbide nano-structured ceramics as SiC constitute interesting materials for high temperature applications and particularly for fourth generation nuclear plants. To elaborate such nano-materials, weighable amounts of SiC nano-powders have to be synthesized first with an accurate control of the grain size and stoichiometry. The inductively coupled plasma and the laser pyrolysis techniques, respectively developed at EMPA Thun and CEA Saclay, allow meeting these requirements. Both techniques are able to produce dozens of grams per hour of silicon carbide nano-powders. The particle size can be adjusted down to around 20 nm for the plasma synthesis and even down to 5-10 nm for the laser pyrolysis. The stoichiometry Si/C can be tuned by the addition of methane into the plasma and acetylene for the laser process. (authors)

  11. Direct analysis of samples by mass spectrometry: From elements to bio-molecules using laser ablation inductively couple plasma mass spectrometry and laser desorption/ionization mass spectrometry

    SciTech Connect (OSTI)

    Perdian, David C.

    2009-08-19

    Mass spectrometric methods that are able to analyze solid samples or biological materials with little or no sample preparation are invaluable to science as well as society. Fundamental research that has discovered experimental and instrumental parameters that inhibit fractionation effects that occur during the quantification of elemental species in solid samples by laser ablation inductively coupled plasma mass spectrometry is described. Research that determines the effectiveness of novel laser desorption/ionization mass spectrometric methods for the molecular analysis of biological tissues at atmospheric pressure and at high spatial resolution is also described. A spatial resolution is achieved that is able to analyze samples at the single cell level.

  12. Comparative study of laminar and turbulent flow model with different operating parameters for radio frequency-inductively coupled plasma torch working at 3??MHz frequency at atmospheric pressure

    SciTech Connect (OSTI)

    Punjabi, Sangeeta B.; Sahasrabudhe, S. N.; Das, A. K.; Joshi, N. K.; Mangalvedekar, H. A.; Kothari, D. C.

    2014-01-15

    This paper provides 2D comparative study of results obtained using laminar and turbulent flow model for RF (radio frequency) Inductively Coupled Plasma (ICP) torch. The study was done for the RF-ICP torch operating at 50?kW DC power and 3?MHz frequency located at BARC. The numerical modeling for this RF-ICP torch is done using ANSYS software with the developed User Defined Function. A comparative study is done between laminar and turbulent flow model to investigate how temperature and flow fields change when using different operating conditions such as (a) swirl and no swirl velocity for sheath gas flow rate, (b) variation in sheath gas flow rate, and (c) variation in plasma gas flow rate. These studies will be useful for different material processing applications.

  13. Laser ablation-inductively coupled plasma-mass spectrometry: Examinations of the origins of polyatomic ions and advances in the sampling of particulates

    SciTech Connect (OSTI)

    Witte, Travis

    2011-11-30

    This dissertation provides a general introduction to Inductively coupled plasma-mass spectrometry (ICP-MS) and laser ablation (LA) sampling, with an examination of analytical challenges in the employment of this technique. It discusses the origin of metal oxide ions (MO+) in LA-ICP-MS, as well as the effect of introducing helium and nitrogen to the aerosol gas flow on the formation of these polyatomic interferences. It extends the study of polyatomic ions in LA-ICP-MS to metal argide (MAr+) species, an additional source of possible significant interferences in the spectrum. It describes the application of fs-LA-ICP-MS to the determination of uranium isotope ratios in particulate samples.

  14. Standard test method for the determination of impurities in plutonium metal: acid digestion and inductively coupled plasma-mass spectroscopy (ICP-MS) analysis

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    2006-01-01

    1.1 This Test Method covers the determination of 58 trace elements in plutonium (Pu) metal. The Pu sample is dissolved in acid, and the concentration of the trace impurities are determined by Inductively Coupled Plasma-Mass Spectroscopy (ICP-MS). 1.2 This Test Method is specific for the determination of trace impurities in Pu metal. It may be applied to other types of Pu materials, such as Pu oxides, if the samples are dissolved and oxidized to the Pu(IV) state. However, it is the responsibility of the user to evaluate the performance of other matrices. 1.3 This standard does not purport to address all of the safety concerns associated with its use. It is the responsibility of the user of this method to establish appropriate safety and health practices and to determine the applicability of regulatory limitations prior to use of this standard.

  15. InP Etching by HI/Xe Inductively Coupled Plasma for Photonic-Crystal Device Fabrication Toshihide IDE, Jun-ichi HASHIMOTO, Kengo NOZAKI, Eiichi MIZUTA and Toshihiko BABA

    E-Print Network [OSTI]

    Baba, Toshihiko

    InP Etching by HI/Xe Inductively Coupled Plasma for Photonic-Crystal Device Fabrication Toshihide: 10.1143/JJAP.45.L102] KEYWORDS: dry etching, ICP, InP, HI, photonic crystal, nanolaser Photonic this temperature is higher than the temperature limit of resists. In recent years, dry etching with HI gas has

  16. Harmonic content and time variation of electron energy distributions in high-plasma-density, low-pressure inductively coupled discharges

    E-Print Network [OSTI]

    Kushner, Mark

    Harmonic content and time variation of electron energy distributions in high-plasma-density, low-the-fly'' OTF Monte Carlo method. The OTF method directly computes the harmonic content of the EEDs using was incorporated into a two-dimensional plasma equipment model to investigate the harmonic content of the EEDs

  17. Comparative study of GaN mesa etch characteristics in Cl{sub 2} based inductively coupled plasma with Ar and BCl{sub 3} as additive gases

    SciTech Connect (OSTI)

    Rawal, Dipendra Singh, E-mail: dsrawal15@gmail.com; Arora, Henika; Sehgal, Bhupender Kumar; Muralidharan, Rangarajan [Solid State Physics Laboratory, Lucknow Road, Timarpur, Delhi-110054 (India)

    2014-05-15

    GaN thin film etching is investigated and compared for mesa formation in inductively coupled plasma (ICP) of Cl{sub 2} with Ar and BCl{sub 3} gas additives using photoresist mask. Etch characteristics are studied as a function of ICP process parameters, viz., ICP power, radio frequency (RF) power, and chamber pressure at fixed total flow rate. The etch rate at each ICP/RF power is 0.1–0.2??m/min higher for Cl{sub 2}/Ar mixture mainly due to higher Cl dissociation efficiency of Ar additive that readily provides Cl ion/radical for reaction in comparison to Cl{sub 2}/BCl{sub 3} mixture. Cl{sub 2}/Ar mixture also leads to better photoresist mask selectivity. The etch-induced roughness is investigated using atomic force microscopy. Cl{sub 2}/Ar etching has resulted in lower root-mean-square roughness of GaN etched surface in comparison to Cl{sub 2}/BCl{sub 3} etching due to increased Ar ion energy and flux with ICP/RF power that enhances the sputter removal of etch product. The GaN surface damage after etching is also evaluated using room temperature photoluminescence and found to be increasing with ICP/RF power for both the etch chemistries with higher degree of damage in Cl{sub 2}/BCl{sub 3} etching under same condition.

  18. Fabrication of ZnO photonic crystals by nanosphere lithography using inductively coupled-plasma reactive ion etching with CH{sub 4}/H{sub 2}/Ar plasma on the ZnO/GaN heterojunction light emitting diodes

    SciTech Connect (OSTI)

    Chen, Shr-Jia; Chang, Chun-Ming; Kao, Jiann-Shiun; Chen, Fu-Rong; Tsai, Chuen-Horng [Engineering and System Science, National Tsing Hua University, Hsinchu, 30013 Taiwan (China); Instrument Technology Research Center, National Applied Research Laboratories, Hsinchu, 300 Taiwan (China); Engineering and System Science, National Tsing Hua University, Hsinchu, 30013 Taiwan (China)

    2010-07-15

    This article reports fabrication of n-ZnO photonic crystal/p-GaN light emitting diode (LED) by nanosphere lithography to further booster the light efficiency. In this article, the fabrication of ZnO photonic crystals is carried out by nanosphere lithography using inductively coupled plasma reactive ion etching with CH{sub 4}/H{sub 2}/Ar plasma on the n-ZnO/p-GaN heterojunction LEDs. The CH{sub 4}/H{sub 2}/Ar mixed gas gives high etching rate of n-ZnO film, which yields a better surface morphology and results less plasma-induced damages of the n-ZnO film. Optimal ZnO lattice parameters of 200 nm and air fill factor from 0.35 to 0.65 were obtained from fitting the spectrum of n-ZnO/p-GaN LED using a MATLAB code. In this article, we will show our recent result that a ZnO photonic crystal cylinder has been fabricated using polystyrene nanosphere mask with lattice parameter of 200 nm and radius of hole around 70 nm. Surface morphology of ZnO photonic crystal was examined by scanning electron microscope.

  19. Coupling effects in inductive discharges with radio frequency substrate biasing

    SciTech Connect (OSTI)

    Schulze, J.; Schuengel, E.; Czarnetzki, U.

    2012-01-09

    Low pressure inductively coupled plasmas (ICP) operated in neon at 27.12 MHz with capacitive substrate biasing (CCP) at 13.56 MHz are investigated by phase resolved optical emission spectroscopy, voltage, and current measurements. Three coupling mechanisms are found potentially limiting the separate control of ion energy and flux: (i) Sheath heating due to the substrate biasing affects the electron dynamics even at high ratios of ICP to CCP power. At fixed CCP power, (ii) the substrate sheath voltage and (iii) the amplitude as well as frequency of plasma series resonance oscillations of the RF current are affected by the ICP power.

  20. Inductively coupled plasma–reactive ion etching of c- and a-plane AlGaN over the entire Al composition range: Effect of BCl{sub 3} pretreatment in Cl{sub 2}/Ar plasma chemistry

    SciTech Connect (OSTI)

    Shah, Amit P.; Laskar, Masihhur R.; Azizur Rahman, A.; Gokhale, Maheshwar R.; Bhattacharya, Arnab

    2013-11-15

    Inductively coupled plasma (ICP)–reactive ion etching (RIE) patterning is a standard processing step for UV and optical photonic devices based on III-nitride materials. There is little research on ICP-RIE of high Al-content AlGaN alloys and for nonpolar nitride orientations. The authors present a comprehensive study of the ICP-RIE of c- and a-plane AlGaN in Cl{sub 2}/Ar plasma over the entire Al composition range. The authors find that the etch rate decreases in general with increasing Al content, with different behavior for c- and a-plane AlGaN. They also study the effect of BCl{sub 3} deoxidizing plasma pretreatment. An ICP deoxidizing BCl{sub 3} plasma with the addition of argon is more efficient in removal of surface oxides from Al{sub x}Ga{sub 1?x}N than RIE alone. These experiments show that Al{sub x}Ga{sub 1?x}N etching is affected by the higher binding energy of AlN and the higher affinity of oxygen to aluminum compared to gallium, with oxides on a-plane AlGaN more difficult to etch as compared to oxides on c-plane AlGaN, specifically for high Al composition materials. The authors achieve reasonably high etch rate (?350 nm/min) for high Al-content materials with a smooth surface morphology at a low DC bias of ??45 VDC.

  1. Use of Electrodeposition for Sample Preparation and Rejection Rate Prediction for Assay of Electroformed Ultra High Purity Copper for 232Th and 238U Prior to Inductively Coupled Plasma Mass Spectrometry (ICP/MS)

    SciTech Connect (OSTI)

    Hoppe, Eric W.; Aalseth, Craig E.; Brodzinski, Ronald L.; Day, Anthony R.; Farmer, Orville T.; Hossbach, Todd W.; McIntyre, Justin I.; Miley, Harry S.; Mintzer, Esther E.; Seifert, Allen; Smart, John E.; Warren, Glen A.

    2008-07-01

    The search for neutrinoless double beta decay in 76Ge has driven the need for ultra-low background Ge detectors shielded by electroformed copper of ultra-high radiopurity (<0.1µBq/kg). Although electrodeposition processes are almost sophisticated enough to produce copper of this purity, to date there are no methods sensitive enough to assay it. Inductively-coupled plasma mass spectrometry (ICP/MS) can detect thorium and uranium at femtogram levels, but in the past, this assay has been hindered by high copper concentrations in the sample. Electrodeposition of copper samples removes copper from the solution while selectively concentrating thorium and uranium contaminants to be assayed by ICP/MS. Spiking 232Th and 238U into the plating bath simulates low purity copper and allows for the calculation of the electrochemical rejection rate of thorium and uranium in the electroplating system. This rejection value will help to model plating bath chemistry.

  2. Apparatus and method for reducing inductive coupling between...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and method for reducing inductive coupling between levitation and drive coils within a magnetic propulsion system United States Patent Patent Number: 6,250,230 Issued: June 26,...

  3. Simulation results of an inductively-coupled rf plasma torch in two and three dimensions for producing a metal matrix composite for nuclear fuel cladding 

    E-Print Network [OSTI]

    Holik III, Eddie Frank (Trey)

    2009-05-15

    I propose to develop a new method for the synthesis of metal matrix composites (MMC) using aerosol reactants in a radio frequency (RF) plasma torch. An inductivelycoupled RF plasma torch (ICPT) may potentially be designed ...

  4. 2110 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 37, NO. 11, NOVEMBER 2009 Low-Pressure Helicon-Plasma Discharge Initiation

    E-Print Network [OSTI]

    Scharer, John E.

    -temperature plasma research. Low- pressure (as low as 1 millitorr) inductively coupled plasmas are used for plasma

  5. Laser sampling system for an inductively-coupled atomic emission spectrometer. Final report

    SciTech Connect (OSTI)

    NONE

    1998-02-15

    A laser sampling system was attached to a Perkin Elmer Optima 3000 inductively-coupled plasma, atomic emission spectrometer that was already installed and operating in the Chemistry and Geochemistry Department at the Colorado School of Mines. The use of the spectrometer has been highly successful. Graduate students and faculty from at least four different departments across the CSM campus have used the instrument. The final report to NSF is appended to this final report. Appendices are included which summarize several projects utilizing this instrument: acquisition of an inductively-coupled plasma atomic emission spectrometer for the geochemistry program; hydrogen damage susceptibility assessment for high strength steel weldments through advanced hydrogen content analysis, 1996 and 1997 annual reports; and methods for determination of hydrogen distribution in high strength steel welds.

  6. Inductive and Electrostatic Acceleration in Relativistic Jet-Plasma Interactions

    SciTech Connect (OSTI)

    Ng, Johnny S.T.; Noble, Robert J.; /SLAC

    2005-07-13

    We report on the observation of rapid particle acceleration in numerical simulations of relativistic jet-plasma interactions and discuss the underlying mechanisms. The dynamics of a charge-neutral, narrow, electron-positron jet propagating through an unmagnetized electron-ion plasma was investigated using a three-dimensional, electromagnetic, particle-in-cell computer code. The interaction excited magnetic filamentation as well as electrostatic (longitudinal) plasma instabilities. In some cases, the longitudinal electric fields generated inductively and electrostatically reached the cold plasma wave-breaking limit, and the longitudinal momentum of about half the positrons increased by 50% with a maximum gain exceeding a factor of two. The results are relevant to understanding the micro-physics at the interface region of an astrophysical jet with the interstellar plasma, for example, the edge of a wide jet or the jet-termination point.

  7. Rapid Wireless Capacitor Charging Using a Multi-Tapped Inductively-Coupled Secondary Coil

    E-Print Network [OSTI]

    Mercier, Patrick P.

    This paper presents an inductive coupling system designed to wirelessly charge ultra-capacitors used as energy storage elements. Although ultra-capacitors offer the native ability to rapidly charge, it is shown that standard ...

  8. Baryon Dissociation in a Strongly Coupled Plasma

    E-Print Network [OSTI]

    Chethan Krishnan

    2008-11-14

    Using the dual string theory, we study a circular baryonic configuration in a wind of strongly coupled N=4 Yang-Mills plasma blowing in the plane of the baryon, before and after a quark has dissociated from it. A simple enough model that captures many interesting features is when there are four quarks in the baryon. As a step towards phenomenology, we compare representative dissociated configurations, and make some comments about their energetics and other properties. Related results that we find include the observation that the screening length formula L_s T ~ (1-v^2)^{1/4} obtained previously for other color singlet configurations, is robust for circular baryons as well.

  9. 180-nm CMOS Wideband Capacitor-free Inductively Coupled Power Receiver and Charger

    E-Print Network [OSTI]

    Rincon-Mora, Gabriel A.

    180-nm CMOS Wideband Capacitor-free Inductively Coupled Power Receiver and Charger Orlando Lazaro.lazaro@ece.gatech.edu, rincon-mora@gatech.edu Abstract: Wireless microsystems like biomedical implants and embedded sensors life is short. Periodically coupling power wirelessly is one way of replenishing onboard batteries

  10. Strongly Coupled Plasmas via Rydberg-Blockade of Cold Atoms

    E-Print Network [OSTI]

    Bannasch, G; Pohl, T

    2013-01-01

    We propose and analyze a new scheme to produce ultracold neutral plasmas deep in the strongly coupled regime. The method exploits the interaction blockade between cold atoms excited to high-lying Rydberg states and therefore does not require substantial extensions of current ultracold plasma experiments. Extensive simulations reveal a universal behavior of the resulting Coulomb coupling parameter, providing a direct connection between the physics of strongly correlated Rydberg gases and ultracold plasmas. The approach is shown to reduce currently accessible temperatures by more than an order of magnitude, which opens up a new regime for ultracold plasma research and cold ion-beam applications with readily available experimental techniques.

  11. Mission Statement Elemental analysis using inductively coupled plasma

    E-Print Network [OSTI]

    Chapman, Michael S.

    and feature pop science experiments such determining lead content in water at our annual Open House. Services to the success of your project. For optimal results, take advantage of the state-of-the-art scienti c resources Analysis Core hosts an annual Open House which typically features pop-science-based themes. These vary from

  12. A Vertical Hydrophone Array Coupled via Inductive Modem for Detecting Deep-Ocean Seismic and

    E-Print Network [OSTI]

    Bohnenstiehl, Delwayne

    A Vertical Hydrophone Array Coupled via Inductive Modem for Detecting Deep-Ocean Seismic synchronization methods based on three-wire serial or NTP network interface, it only requires an insulated single is active with seismicity and submarine eruptions. The results of the four-month long monitoring

  13. Effect of strongly coupled plasma on photoionization cross section

    SciTech Connect (OSTI)

    Das, Madhusmita

    2014-01-15

    The effect of strongly coupled plasma on the ground state photoionization cross section is studied. In the non relativistic dipole approximation, cross section is evaluated from bound-free transition matrix element. The bound and free state wave functions are obtained by solving the radial Schrodinger equation with appropriate plasma potential. We have used ion sphere potential (ISP) to incorporate the plasma effects in atomic structure calculation. This potential includes the effect of static plasma screening on nuclear charge as well as the effect of confinement due to the neighbouring ions. With ISP, the radial equation is solved using Shooting method approach for hydrogen like ions (Li{sup +2}, C{sup +5}, Al{sup +12}) and lithium like ions (C{sup +3}, O{sup +5}). The effect of strong screening and confinement is manifested as confinement resonances near the ionization threshold for both kinds of ions. The confinement resonances are very much dependent on the edge of the confining potential and die out as the plasma density is increased. Plasma effect also results in appearance of Cooper minimum in lithium like ions, which was not present in case of free lithium like ions. With increasing density the position of Cooper minimum shifts towards higher photoelectron energy. The same behaviour is also true for weakly coupled plasma where plasma effect is modelled by Debye-Huckel potential.

  14. Probing strongly coupled anisotropic plasmas from higher curvature gravity

    E-Print Network [OSTI]

    Viktor Jahnke; Anderson Seigo Misobuchi

    2015-10-23

    We consider five-dimensional AdS-axion-dilaton gravity with a Gauss-Bonnet term and use a black brane solution displaying spatial anisotropy as the gravity dual of a strongly coupled anisotropic plasma. We compute several observables relevant to the study of the plasma, namely, the drag force, the jet quenching parameter, the quarkonium potential and the thermal photon production. The effects of higher derivative corrections and of the anisotropy are discussed and compared with previous results.

  15. Viscoelastic modes in a strongly coupled, cold, magnetized dusty plasma

    SciTech Connect (OSTI)

    Banerjee, Debabrata; Mylavarapu, Janaki Sita; Chakrabarti, Nikhil

    2010-11-15

    A generalized hydrodynamical model has been used to study the low frequency modes in a strongly coupled, cold, magnetized dusty plasma. Such plasmas exhibit elastic properties due to the strong correlations among dust particles and the tensile stresses imparted by the magnetic field. It has been shown that longitudinal compressional Alfven modes and elasticity modified transverse shear mode exist in such a medium. The features of these collective modes are established and discussed.

  16. Viscoelastic modes in a strongly coupled cold magnetized dusty plasma

    E-Print Network [OSTI]

    Banerjee, Debabrata; Chakrabarti, Nikhil

    2013-01-01

    A generalized hydrodynamical model has been used to study low frequency modes in a strongly coupled, cold, magnetized dusty plasma. Such plasmas exhibit elastic properties due to strong correlations among dust particles and the tensile stresses imparted by the magnetic field. It has been shown that longitudinal compressional Alfven modes and elasticity modified transverse shear mode exist in such a medium. The features of these collective modes are established and discussed.

  17. Parton picture for the strongly coupled SYM plasma

    E-Print Network [OSTI]

    E. Iancu

    2008-05-27

    Deep inelastic scattering off the strongly coupled N=4 supersymmetric Yang-Mills plasma at finite temperature can be computed within the AdS/CFT correspondence, with results which are suggestive of a parton picture for the plasma. Via successive branchings, essentially all partons cascade down to very small values of the longitudinal momentum fraction x and to transverse momenta smaller than the saturation momentum Q_s\\sim T/x. This scale Q_s controls the plasma interactions with a hard probe, in particular, the jet energy loss and its transverse momentum broadening.

  18. Model for a transformer-coupled toroidal plasma source

    SciTech Connect (OSTI)

    Rauf, Shahid; Balakrishna, Ajit; Chen Zhigang; Collins, Ken [Applied Materials, Inc., 974 E. Arques Avenue, Sunnyvale, California 94085 (United States)

    2012-01-15

    A two-dimensional fluid plasma model for a transformer-coupled toroidal plasma source is described. Ferrites are used in this device to improve the electromagnetic coupling between the primary coils carrying radio frequency (rf) current and a secondary plasma loop. Appropriate components of the Maxwell equations are solved to determine the electromagnetic fields and electron power deposition in the model. The effect of gas flow on species transport is also considered. The model is applied to 1 Torr Ar/NH{sub 3} plasma in this article. Rf electric field lines form a loop in the vacuum chamber and generate a plasma ring. Due to rapid dissociation of NH{sub 3}, NH{sub x}{sup +} ions are more prevalent near the gas inlet and Ar{sup +} ions are the dominant ions farther downstream. NH{sub 3} and its by-products rapidly dissociate into small fragments as the gas flows through the plasma. With increasing source power, NH{sub 3} dissociates more readily and NH{sub x}{sup +} ions are more tightly confined near the gas inlet. Gas flow rate significantly influences the plasma characteristics. With increasing gas flow rate, NH{sub 3} dissociation occurs farther from the gas inlet in regions with higher electron density. Consequently, more NH{sub 4}{sup +} ions are produced and dissociation by-products have higher concentrations near the outlet.

  19. Suppression of Rayleigh Taylor instability in strongly coupled plasmas

    SciTech Connect (OSTI)

    Das, Amita; Kaw, Predhiman [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)

    2014-06-15

    The Rayleigh Taylor instability in a strongly coupled plasma medium has been investigated using the equations of generalized hydrodynamics. It is demonstrated that the visco-elasticity of the strongly coupled medium due to strong inter particle correlations leads to a suppression of the Rayleigh Taylor instability unless certain threshold conditions are met. The relevance of these results to experiments on laser compression of matter to high densities including those related to inertial confinement fusion using lasers has also been shown.

  20. Plasma Diagnostics and Plasma-Surface Interactions in Inductively Coupled Plasmas

    E-Print Network [OSTI]

    Titus, Monica Joy

    2010-01-01

    ICP simulation power to achieve wall ion currents equivalentapplied source power) until the simulation wall ion currentapplied source power) until the simulation wall ion current

  1. Plasma Diagnostics and Plasma-Surface Interactions in Inductively Coupled Plasmas

    E-Print Network [OSTI]

    Titus, Monica Joy

    2010-01-01

    are protected with a layer of polyimide coating and theplasma (ICP) chamber. Polyimide Coating Electronic Moduleprotected with a layer of polyimide coating and communicate

  2. Plasma Diagnostics and Plasma-Surface Interactions in Inductively Coupled Plasmas

    E-Print Network [OSTI]

    Titus, Monica Joy

    2010-01-01

    6.4.3 Chemical Dosimeter Application …………………………………………. 6.5using a chemical dosimeter-type monitor is demonstrated. Theion flux in the chemical dosimeter experiments. As shown

  3. 718 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 34, NO. 3, JUNE 2006 Nonlinear Effects and Anomalous Transport

    E-Print Network [OSTI]

    Chen, Francis F.

    -frequency plasmas: anomalous skin depth in inductively coupled plasmas, transport by fluctuations in helicon plasmas. II. ANOMALOUS SKIN DEPTH IN ICPS Inductively coupled plasmas (ICPs) are plasma sources ex- cited. The first is a spiral coil shaped like a stove-top heating element and placed on the dielectric top cover

  4. An experimental study and modeling of Transformer-Coupled Toroidal Plasma processing of materials

    E-Print Network [OSTI]

    Bai, Bo, Ph. D. Massachusetts Institute of Technology

    2006-01-01

    The Transformer Coupled Toroidal Plasma (TCTP) source uses a high power density plasma formed in a toroidal-shaped chamber by transformer coupling using a magnetic core. The objectives of the thesis are (1) to characterize ...

  5. Shear Waves in an inhomogeneous strongly coupled dusty plasma

    E-Print Network [OSTI]

    Janaki, M S; Chakrabarti, N

    2013-01-01

    The properties of electrostatic transverse shear waves propagating in a strongly coupled dusty plasma with an equilibrium density gradient are examined using the generalized hydrodynamic equation. In the usual kinetic limit, the resulting equation has similarity to zero energy Schrodinger's equation. This has helped in obtaining some exact eigenmode solutions in both cartesian and cylindrical geometries for certain nontrivial density profiles. The corresponding velocity profiles and the discrete eigenfrequencies are obtained for several interesting situations and their physics discussed.

  6. Quasilocalized charge approximation in strongly coupled plasma physics

    SciTech Connect (OSTI)

    Golden, Kenneth I. [Department of Mathematics and Statistics, Department of Physics, University of Vermont, Burlington, Vermont 05401-1455 (United States)] [Department of Mathematics and Statistics, Department of Physics, University of Vermont, Burlington, Vermont 05401-1455 (United States); Kalman, Gabor J. [Department of Physics, Boston College, Chestnut Hill, Massachusetts 02467 (United States)] [Department of Physics, Boston College, Chestnut Hill, Massachusetts 02467 (United States)

    2000-01-01

    The quasilocalized charge approximation (QLCA) was proposed in 1990 [G. Kalman and K. I. Golden, Phys. Rev. A 41, 5516 (1990)] as a formalism for the analysis of the dielectric response tensor and collective mode dispersion in strongly coupled Coulomb liquids. The approach is based on a microscopic model in which the charges are quasilocalized on a short-time scale in local potential fluctuations. The authors review the application of the QLC approach to a variety of systems which can exhibit strongly coupled plasma behavior: (i) the one-component plasma (OCP) model in three dimensions (e.g., laser-cooled trapped ions) and (ii) in two dimensions (e.g., classical 2D electron liquid trapped above the free surface of liquid helium), (iii) binary ionic mixture in a neutralizing uniform background (e.g., carbon-oxygen white dwarf interiors), (iv) charged particle bilayers (e.g., semiconductor electronic bilayers), and (v) charged particles in polarizable background (e.g., laboratory dusty plasmas). (c) 2000 American Institute of Physics.

  7. Exact propagating nonlinear singular disturbances in strongly coupled dusty plasmas

    SciTech Connect (OSTI)

    Das, Amita; Tiwari, Sanat Kumar; Kaw, Predhiman; Sen, Abhijit [Institute for Plasma Research, Bhat, Gandhinagar, Gujarat 382428 (India)

    2014-08-15

    The dynamical response of the strongly coupled dusty plasma medium has recently been described by utilizing the Generalized Hydrodynamic (GHD) model equations. The GHD equations capture the visco-elastic properties of the medium and have been successful in predicting a host of phenomena (e.g., existence of novel transverse shear waves in the fluid medium, modification of longitudinal wave dispersion by elastic effects, etc.) which have found experimental confirmation. In this paper, the nonlinear longitudinal response of the medium governed by GHD equations in strong coupling limit is discussed analytically. The structure of the equations rules out the balance between dispersion and nonlinearity, thereby, forbidding soliton formation. However, a host of new varieties of nonlinear solutions are found to exist, which have singular spatial profiles and yet have conservative properties. For instance, existence of novel conservative shock structures with zero strength is demonstrated, waves whose breaking produces no dissipation in the medium are observed, propagating solutions which produce cusp like singularities can exist and so on. It is suggested that simulations and experiments should look for these novel nonlinear structures in the large amplitude strong coupling limit of longitudinal disturbances in dusty plasmas.

  8. Strongly coupled plasma with electric and magnetic charges

    E-Print Network [OSTI]

    Jinfeng Liao; Edward Shuryak

    2006-12-12

    A number of theoretical and lattice results lead us to believe that Quark-Gluon Plasma not too far from $T_c$ contains not only electrically charged quasiparticles -- quarks and gluons -- but magnetically charged ones -- monopoles and dyons -- as well. Although binary systems like charge-monopole and charge-dyon were considered in details before in both classical and quantum settings, it is the first study of coexisting electric and magnetic particles in many-body context. We perform Molecular Dynamics study of strongly coupled plasmas with $\\sim 1000$ particles and different fraction of magnetic charges. Correlation functions and Kubo formulae lead to such transport properties as diffusion constant, shear viscosity and electric conductivity: we compare the first two with empirical data from RHIC experiments as well as results from AdS/CFT correspondence. We also study a number of collective excitations in these systems.

  9. Shear Flow instability in a strongly coupled dusty plasma

    E-Print Network [OSTI]

    Banerjee, D; Chakrabarti, N

    2013-01-01

    Linear stability analysis of strongly coupled incompressible dusty plasma in presence of shear flow has been carried out using Generalized Hydrodynamical(GH) model. With the proper Galilean invariant GH model, a nonlocal eigenvalue analysis has been done using different velocity profiles. It is shown that the effect of elasticity enhances the growth rate of shear flow driven Kelvin- Helmholtz (KH) instability. The interplay between viscosity and elasticity not only enhances the growth rate but the spatial domain of the instability is also widened. The growth rate in various parameter space and the corresponding eigen functions are presented.

  10. Apparatus having inductively coupled coaxial coils for measuring buildup of slay or ash in a furnace

    DOE Patents [OSTI]

    Mathur, Mahendra P. (Pittsburgh, PA); Ekmann, James M. (Bethel Park, PA)

    1989-01-01

    The buildup of slag or ash on the interior surface of a furnace wall is monitored by disposing two coils to form a transformer which is secured adjacent to the inside surface of the furnace wall. The inductive coupling between the two coils of the transformer is affected by the presence of oxides of iron in the slag or ash which is adjacent to the transformer, and the application of a voltage to one winding produces a voltage at the other winding that is related to the thickness of the slag or ash buildup on the inside surface of the furnace wall. The output of the other winding is an electrical signal which can be used to control an alarm or the like or provide an indication of the thickness of the slag or ash buildup at a remote location.

  11. The Weibel instability in a strongly coupled plasma

    SciTech Connect (OSTI)

    Mahdavi, M. Khanzadeh, H.

    2014-06-15

    In this paper, the growth rate of the Weibel instability is calculated for an energetic relativistic electron beam penetrated into a strongly coupled plasma, where the collision effects of background electron-ion scattering play an important role in equations. In order to calculate the growth rate of the Weibel instability, two different models of anisotropic distribution function are used. First, the distribution of the plasma and beam electrons considered as similar forms of bi-Maxwellian distribution. Second, the distribution functions of the plasma electrons and the beam electrons follows bi-Maxwellian and delta-like distributions, respectively. The obtained results show that the collision effect decreases the growth rate in two models. When the distribution function of electrons beam is in bi-Maxwellian form, the instability growth rate is greater than where the distribution function of beam electrons is in delta-like form, because, the anisotropic temperature for bi-Maxwellian distribution function in velocity space is greater than the delta-like distribution function.

  12. A Non-Resonant Self-Synchronizing Inductively Coupled 0.18-m CMOS Power Receiver and Charger

    E-Print Network [OSTI]

    Rincon-Mora, Gabriel A.

    A Non-Resonant Self-Synchronizing Inductively Coupled 0.18-µm CMOS Power Receiver and Charger wireless microsensors, cellular phones, and biomedical implants, to name a few, is on the rise. Not surprisingly, recharging batteries wirelessly is becoming increasingly popular today. Still, small pickup coils

  13. Diagnostics and modeling of plasma processes in ion sources

    E-Print Network [OSTI]

    Vertes, Akos

    radiation (inductively coupled plasma (ICI'), microwave-induced plasma (MU'), pulsed laser). The present-8), radiofrequency (9) and microwave ion sources (10-12) are under intense investigation. Diligent research

  14. Testing of inductively coupled Eddy current position sensor of diverse safety rod in sodium

    SciTech Connect (OSTI)

    Vijayashree, R.; Veeraswamy, R.; Nashine, B. K.; Dash, S. K.; Sharma, P.; Rajan, K. K.; Vijayakumar, G.; Rao, C. B.; Sosamma, S.; Kalyanasundaram, P. [Indira Gandhi Centre for Atomic Research, Dept. of Atomic Energy, Kalpakkam - 603 102 (India)

    2011-07-01

    Prototype Fast Breeder Reactor (PFBR) is 500 MWe sodium cooled reactor under construction at Kalpakkam (India)). To improve the reliability of shutdown, Diverse Safety Rods (DSRs) are used in-addition to normal Control and Safety rods. During reactor operating condition, the DSR is parked above the active core and held in its top position by an electromagnet. In the event of a scram signal from the safety logic, the electromagnet holding the DSR is de-energised. Hence the DSR is released into the active core and at the end of travel DSR gets deposited in its bottom position. Because of the mechanical constraints, hard wired connectivity is not permitted from the DSR subassembly to the instrumentation outside the reactor. Hence an inductively coupled Eddy Current Position Sensor (ECPS) has been conceptualized to detect that the DSR has reached its bottom most position and to measure the drop time. Results of feasibility study on laboratory model have been reported earlier. Testing of a 1:1 scale engineering model of ECPS is reported in this paper. Results obtained from the high temperature sodium testing of ECPS indicate a clearly measurable change in pick up voltage with sensitivity of 11 % at 675 Hz. The ECPS is in advanced stage of implementation in DSRDM of PFBR. (authors)

  15. Dense strongly coupled plasma in double laser pulse ablation of lithium: Experiment and simulation

    SciTech Connect (OSTI)

    Kumar, Ajai; Sivakumaran, V.; Ganesh, R.; Joshi, H. C. [Institute for Plasma Research, Bhat, Gandhinagar-382428 (India)] [Institute for Plasma Research, Bhat, Gandhinagar-382428 (India); Ashwin, J. [Weizmann Institute of Science, Rehovot - 76100 (Israel)] [Weizmann Institute of Science, Rehovot - 76100 (Israel)

    2013-08-15

    In a simple method of low power nano-second double pulsed laser ablation experiment in collinear geometry, formation of high density strongly coupled plasma is demonstrated. Using time-resolved measurements of the Stark broadened line width and line intensity ratio of the emission lines, the density and temperature of the plasma were estimated respectively. In this experiment, it is shown that ions are strongly coupled (ion-ion coupling parameter comes out to be >4). For comparison, both single and double pulsed laser ablations are presented. For the estimated experimental plasma parameters, first principle Langevin dynamics simulation corroborates the existence of a strongly coupled regime.

  16. Performance Optimization Criteria for Pulsed Inductive Plasma Acceleration Kurt A. Polzin

    E-Print Network [OSTI]

    the discharge is inductively driven. In ad- dition, a wider variety of propellants (e.g. CO2, H2O) be- comes as a greater fraction of the propellant is loaded nearer to the inductive acceleration coil. I. INTRODUCTION

  17. Kolmogorov flow in two dimensional strongly coupled dusty plasma

    SciTech Connect (OSTI)

    Gupta, Akanksha; Ganesh, R., E-mail: ganesh@ipr.res.in; Joy, Ashwin [Institute for Plasma Research, Bhat Gandhinagar, Gujarat 382 428 (India)

    2014-07-15

    Undriven, incompressible Kolmogorov flow in two dimensional doubly periodic strongly coupled dusty plasma is modelled using generalised hydrodynamics, both in linear and nonlinear regime. A complete stability diagram is obtained for low Reynolds numbers R and for a range of viscoelastic relaxation time ?{sub m} [0?

  18. Plasma and Fusion Research: Regular Articles Volume 2, 004 (2007) A Self-Organized Plasma with Induction, Reconnection, and

    E-Print Network [OSTI]

    Ji, Hantao

    2007-01-01

    2007 The Japan Society of Plasma Science and Nuclear Fusion Research Keywords: SPIRIT, FRC (Field properties [3]. Although high-beta FRC equilibria can be obtained relatively easily, plasma life- times these three critical issues by stabilizing and sus- taining an FRC plasma with the use of plasma shaping

  19. CHAPTER 7. BERYLLIUM ANALYSIS BY NON-PLASMA BASED METHODS

    SciTech Connect (OSTI)

    Ekechukwu, A

    2009-04-20

    The most common method of analysis for beryllium is inductively coupled plasma atomic emission spectrometry (ICP-AES). This method, along with inductively coupled plasma mass spectrometry (ICP-MS), is discussed in Chapter 6. However, other methods exist and have been used for different applications. These methods include spectroscopic, chromatographic, colorimetric, and electrochemical. This chapter provides an overview of beryllium analysis methods other than plasma spectrometry (inductively coupled plasma atomic emission spectrometry or mass spectrometry). The basic methods, detection limits and interferences are described. Specific applications from the literature are also presented.

  20. Under consideration for publication in J. Plasma Phys. 1 Flow dynamics and magnetic induction in

    E-Print Network [OSTI]

    .g. turbulence in thermonuclear fusion plasmas). Within the magnetohydrodynamic (MHD) frame of description

  1. Coupled microwave ECR and radio-frequency plasma source for plasma processing

    DOE Patents [OSTI]

    Tsai, Chin-Chi (Oak Ridge, TN); Haselton, Halsey H. (Knoxville, TN)

    1994-01-01

    In a dual plasma device, the first plasma is a microwave discharge having its own means of plasma initiation and control. The microwave discharge operates at electron cyclotron resonance (ECR), and generates a uniform plasma over a large area of about 1000 cm.sup.2 at low pressures below 0.1 mtorr. The ECR microwave plasma initiates the second plasma, a radio frequency (RF) plasma maintained between parallel plates. The ECR microwave plasma acts as a source of charged particles, supplying copious amounts of a desired charged excited species in uniform manner to the RF plasma. The parallel plate portion of the apparatus includes a magnetic filter with static magnetic field structure that aids the formation of ECR zones in the two plasma regions, and also assists in the RF plasma also operating at electron cyclotron resonance.

  2. Coupled microwave ECR and radio-frequency plasma source for plasma processing

    DOE Patents [OSTI]

    Tsai, C.C.; Haselton, H.H.

    1994-03-08

    In a dual plasma device, the first plasma is a microwave discharge having its own means of plasma initiation and control. The microwave discharge operates at electron cyclotron resonance (ECR), and generates a uniform plasma over a large area of about 1000 cm[sup 2] at low pressures below 0.1 mtorr. The ECR microwave plasma initiates the second plasma, a radio frequency (RF) plasma maintained between parallel plates. The ECR microwave plasma acts as a source of charged particles, supplying copious amounts of a desired charged excited species in uniform manner to the RF plasma. The parallel plate portion of the apparatus includes a magnetic filter with static magnetic field structure that aids the formation of ECR zones in the two plasma regions, and also assists in the RF plasma also operating at electron cyclotron resonance. 4 figures.

  3. Collisional, magnetic, and nonlinear skin effect in radio-frequency plasmas Francis F. Chen

    E-Print Network [OSTI]

    Chen, Francis F.

    . CLASSICAL VS ANOMALOUS SKIN EFFECT Inductively coupled plasmas ICPs are commonly used in plasma processing.11 The experiments of Godyak et al.3­6,9 were performed with a spiral ``stove-top'' antenna, which

  4. SIMULATIONS OF LASER PULSE COUPLING AND TRANSMISSION EFFICIENCY IN PLASMA CHANNELS

    E-Print Network [OSTI]

    Geddes, Cameron Guy Robinson

    and, hence, the maximum energy of trapped electrons [1]. Energy efficient coupling of laser pulses due to tunneling ioniza- tion of neutral gas on the periphery of the gas jet, ioniza- tion of neutral- tances (few millimeters). More precisely, ionized plasmas can sustain electron plasma waves (EPW

  5. Modeling of magnetically enhanced capacitively coupled plasma sources: ArC4F8 O2 discharges

    E-Print Network [OSTI]

    Kushner, Mark

    Modeling of magnetically enhanced capacitively coupled plasma sources: ArÕC4F8 ÕO2 discharges Alex Magnetically enhanced, capacitively coupled radio frequency plasma sources are finding continued use increase the plasma density at a given pressure or to lower the operating pressure. The use of MERIEs

  6. Recent Advances in the SPIRIT (Self-organized Plasma with Induction, Reconnection, and Injection Techniques)

    E-Print Network [OSTI]

    Ji, Hantao

    features of this concept are: (1) formation of large-flux Field Reversed Configuration (FRC) plasmas for large-flux FRCs. An improved understanding of FRC stability over plasma shape and kinetic parameter has been obtained in MRX. New numerical simulations showed that FRC plasmas can be globally stabilized

  7. Selective killing of ovarian cancer cells through induction of apoptosis by nonequilibrium atmospheric pressure plasma

    SciTech Connect (OSTI)

    Iseki, Sachiko; Tanaka, Hiromasa; Kondo, Hiroki; Hori, Masaru; Nakamura, Kae; Hayashi, Moemi; Kajiyama, Hiroaki; Kikkawa, Fumitaka; Kano, Hiroyuki

    2012-03-12

    Two independent ovarian cancer cell lines and fibroblast controls were treated with nonequilibrium atmospheric pressure plasma (NEAPP). Most ovarian cancer cells were detached from the culture dish by continuous plasma treatment to a single spot on the dish. Next, the plasma source was applied over the whole dish using a robot arm. In vitro cell proliferation assays showed that plasma treatments significantly decreased proliferation rates of ovarian cancer cells compared to fibroblast cells. Flow cytometry and western blot analysis showed that plasma treatment of ovarian cancer cells induced apoptosis. NEAPP could be a promising tool for therapy for ovarian cancers.

  8. Visco-elastic fluid simulations of coherent structures in strongly coupled dusty plasma medium

    SciTech Connect (OSTI)

    Singh Dharodi, Vikram; Kumar Tiwari, Sanat; Das, Amita, E-mail: amita@ipr.res.in [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)

    2014-07-15

    A generalized hydrodynamic model depicting the behaviour of visco-elastic fluids has often been invoked to explore the behaviour of a strongly coupled dusty plasma medium below their crystallization limit. The model has been successful in describing the collective normal modes of the strongly coupled dusty plasma medium observed experimentally. The paper focuses on the study of nonlinear dynamical characteristic features of this model. Specifically, the evolution of coherent vorticity patches is being investigated here within the framework of this model. A comparison with Newtonian fluids and molecular dynamics simulations treating the dust species interacting through the Yukawa potential has also been presented.

  9. Pedestal Fueling Simulations with a Coupled Kinetic-kinetic Plasma-neutral Transport Code

    SciTech Connect (OSTI)

    D.P. Stotler, C.S. Chang, S.H. Ku, J. Lang and G.Y. Park

    2012-08-29

    A Monte Carlo neutral transport routine, based on DEGAS2, has been coupled to the guiding center ion-electron-neutral neoclassical PIC code XGC0 to provide a realistic treatment of neutral atoms and molecules in the tokamak edge plasma. The DEGAS2 routine allows detailed atomic physics and plasma-material interaction processes to be incorporated into these simulations. The spatial pro le of the neutral particle source used in the DEGAS2 routine is determined from the uxes of XGC0 ions to the material surfaces. The kinetic-kinetic plasma-neutral transport capability is demonstrated with example pedestal fueling simulations.

  10. Energy Conservation Tests of a Coupled Kinetic-kinetic Plasma-neutral Transport Code

    SciTech Connect (OSTI)

    Stotler, D. P.; Chang, C. S.; Ku, S. H.; Lang, J.; Park, G.

    2012-08-29

    A Monte Carlo neutral transport routine, based on DEGAS2, has been coupled to the guiding center ion-electron-neutral neoclassical PIC code XGC0 to provide a realistic treatment of neutral atoms and molecules in the tokamak edge plasma. The DEGAS2 routine allows detailed atomic physics and plasma-material interaction processes to be incorporated into these simulations. The spatial pro le of the neutral particle source used in the DEGAS2 routine is determined from the uxes of XGC0 ions to the material surfaces. The kinetic-kinetic plasma-neutral transport capability is demonstrated with example pedestal fueling simulations.

  11. Theoretical investigation of phase-controlled bias effect in capacitively coupled plasma discharges

    SciTech Connect (OSTI)

    Kwon, Deuk-Chul; Yoon, Jung-Sik [Convergence Plasma Research Center, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of)

    2011-07-15

    We theoretically investigated the effect of phase difference between powered electrodes in capacitively coupled plasma (CCP) discharges. Previous experimental result has shown that the plasma potential could be controlled by using a phase-shift controller in CCP discharges. In this work, based on the previously developed radio frequency sheath models, we developed a circuit model to self-consistently determine the bias voltage from the plasma parameters. Results show that the present theoretical model explains the experimental results quite well and there is an optimum value of the phase difference for which the V{sub dc}/V{sub pp} ratio becomes a minimum.

  12. Influence of finite geometrical asymmetry of the electrodes in capacitively coupled radio frequency plasma

    SciTech Connect (OSTI)

    Bora, B., E-mail: bbora@cchen.cl; Soto, L. [Comisión Chilena de Energía Nuclear, Santiago, Chile and Center for Research and Applications in Plasma Physics and Pulsed Power, P4 (Chile)

    2014-08-15

    Capacitively coupled radio frequency (CCRF) plasmas are widely studied in last decades due to the versatile applicability of energetic ions, chemically active species, radicals, and also energetic neutral species in many material processing fields including microelectronics, aerospace, and biology. A dc self-bias is known to generate naturally in geometrically asymmetric CCRF plasma because of the difference in electrode sizes known as geometrical asymmetry of the electrodes in order to compensate electron and ion flux to each electrode within one rf period. The plasma series resonance effect is also come into play due to the geometrical asymmetry and excited several harmonics of the fundamental in low pressure CCRF plasma. In this work, a 13.56?MHz CCRF plasma is studied on the based on the nonlinear global model of asymmetric CCRF discharge to understand the influences of finite geometrical asymmetry of the electrodes in terms of generation of dc self-bias and plasma heating. The nonlinear global model on asymmetric discharge has been modified by considering the sheath at the grounded electrode to taking account the finite geometrical asymmetry of the electrodes. The ion density inside both the sheaths has been taken into account by incorporating the steady-state fluid equations for ions considering that the applied rf frequency is higher than the typical ion plasma frequency. Details results on the influences of geometrical asymmetry on the generation of dc self-bias and plasma heating are discussed.

  13. Resistive wall mode and neoclassical tearing mode coupling in rotating tokamak plasmas

    E-Print Network [OSTI]

    McAdams, Rachel; Chapman, I T

    2013-01-01

    A model system of equations has been derived to describe a toroidally rotating tokamak plasma, unstable to Resistive Wall Modes (RWMs) and metastable to Neoclassical Tearing Modes (NTMs), using a linear RWM model and a nonlinear NTM model. If no wall is present, the NTM growth shows the typical threshold/saturation island widths, whereas a linearly unstable kink mode grows exponentially in this model plasma system. When a resistive wall is present, the growth of the linearly unstable RWM is accelerated by an unstable island: a form of coupled RWM-NTM mode. Crucially, this coupled system has no threshold island width, giving the impression of a triggerless NTM, observed in high beta tokamak discharges. In addition, increasing plasma rotation at the island location can mitigate its growth, but does not restore the threshold width.

  14. Longitudinal electric current in classical collisional Maxwellian plasma, inducted by transversal electromagnetic wave

    E-Print Network [OSTI]

    Latyshev, A V

    2015-01-01

    Kinetic Vlasov equation for collisional Maxwellian plasmas is used. Collision integral of BGK (Bhatnagar, Gross and Krook) type is applied. From Vlasov equation we find distribution function of electrons in square-law approximation on size of transversal electric field. The formula for electric current calculation is deduced. This formula contains an one-dimensional quadrature. It is shown, that nonlinearity leads to revealing of the longitudinal electric current directed along a wave vector. This longitudinal current is perpendicular to known so-called transversal classical current. The classical current turns out at the linear analysis. The longitudinal current in case of small values of wave numbers is calculated. When frequency of collisions tends to zero, all received formulas for collisional plasmas pass in the known corresponding results for collisionless plasmas. Graphic research of dimensionless density of a current is carried out.

  15. Design of Dual-Polarization Horn-Coupled Kinetic Inductance Detectors for Cosmic Microwave Background Polarimetry

    E-Print Network [OSTI]

    Bryan, Sean; Che, George; Day, Peter; Flanigan, Daniel; Johnson, Bradley R; Jones, Glenn; Kjellstrand, Bjorn; Limon, Michele; Mauskopf, Philip; McCarrick, Heather; Miller, Amber; Smiley, Brian

    2015-01-01

    Mapping the polarization of the Cosmic Microwave Background is yielding exciting data on the origin of the universe, the reionization of the universe, and the growth of cosmic structure. Kilopixel arrays represent the current state of the art, but advances in detector technology are needed to enable the larger detector arrays needed for future measurements. Here we present a design for single-band dual-polarization Kinetic Inductance Detectors (KIDs) at 20% bandwidths centered at 145, 220, and 280 GHz. The detection and readout system is nearly identical to the successful photon-noise-limited aluminum Lumped-Element KIDs that have been recently built and tested by some of the authors. Fabricating large focal plane arrays of the feed horns and quarter-wave backshorts requires only conventional precision machining. Since the detectors and readout lines consist only of a single patterned aluminum layer on a SOI wafer, arrays of the detectors can be built commercially or at a standard university cleanroom.

  16. Apparatus and method for reducing inductive coupling between levitation and drive coils within a magnetic propulsion system

    DOE Patents [OSTI]

    Post, Richard F. (Walnut Creek, CA)

    2001-01-01

    An apparatus and method is disclosed for reducing inductive coupling between levitation and drive coils within a magnetic levitation system. A pole array has a magnetic field. A levitation coil is positioned so that in response to motion of the magnetic field of the pole array a current is induced in the levitation coil. A first drive coil having a magnetic field coupled to drive the pole array also has a magnetic flux which induces a parasitic current in the levitation coil. A second drive coil having a magnetic field is positioned to attenuate the parasitic current in the levitation coil by canceling the magnetic flux of the first drive coil which induces the parasitic current. Steps in the method include generating a magnetic field with a pole array for levitating an object; inducing current in a levitation coil in response to motion of the magnetic field of the pole array; generating a magnetic field with a first drive coil for propelling the object; and generating a magnetic field with a second drive coil for attenuating effects of the magnetic field of the first drive coil on the current in the levitation coil.

  17. Experimental and numerical studies of neutral gas depletion in an inductively coupled plasma

    E-Print Network [OSTI]

    Shimada, Masashi

    2006-01-01

    on Rare?ed Gas Dynamics, St. Petersburg, Russia (2006),on Rare?ed Gas Dynamics, St. Petersburg, Russia, to beRar- e?ed Gas Dynamics, St. Petersburg, Russia. In Chapter

  18. REPORT OF THE INDUCTIVELY COUPLED PLASMA -MASS SPECTROMETRY (ICP-MS)

    E-Print Network [OSTI]

    through varied research and the analysis of samples from industry, particularly from the environmental) (Fig. 8) 1 Autosampler (Fig. 10) 1 Flow Injector (Fig, 9) 1 Peristaltic Pump #12;-3- CLEAN LABORATORY

  19. Demountable direct injection high efficiency nebulizer for inductively coupled plasma mass spectrometry

    DOE Patents [OSTI]

    Montaser, Akbar; Westphal, Craig S.; Kahen, Kaveh; Rutkowski, William F.; Acon, Billy W.

    2006-12-05

    A nebulizer adapted for adjusting a position of a capillary tube contained within the nebulizer is provided. The nebulizer includes an elongated tubular shell having a gas input port and a gas output port, a capillary adjustment adapter for displacing the capillary tube in a lateral direction via a rotational force, and a connector for connecting the elongated tubular shell, the capillary adjustment adapter and the capillary tube.

  20. Improvements to Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverseIMPACT EVALUATION PLAN FOR THE SITE-218 58 84(Technical Report) | SciTechfor

  1. Ab-initio calculations on two-electron ions in strongly coupled plasma environment

    E-Print Network [OSTI]

    Bhattacharyya, S; Mukherjee, T K

    2015-01-01

    In this work, the controversy between the interpretations of recent measurements on dense aluminum plasma created with Linac coherent light sources (LCLS) X-ray free electron laser (FEL) and Orion laser has been addressed. In both kind of experiments, helium-like and hydrogen-like spectral lines are used for plasma diagnostics . However, there exist no precise theoretical calculations for He-like ions within dense plasma environment. The strong need for an accurate theoretical estimates for spectral properties of He-like ions in strongly coupled plasma environment leads us to perform ab initio calculations in the framework of Rayleigh-Ritz variation principle in Hylleraas coordinates where ion-sphere potential is used. An approach to resolve the long-drawn problem of numerical instability for evaluating two-electron integrals with extended basis inside a finite domain is presented here. The present values of electron densities corresponding to disappearance of different spectral lines obtained within the fram...

  2. Effects of gas pressure on 60/13.56 MHz dual-frequency capacitively coupled plasmas

    SciTech Connect (OSTI)

    Yuan, Q. H.; Yin, G. Q. [Key Laboratory of Atomic and Molecular Physics and Functional Materials of Gansu Province, College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070 (China); Xin, Y.; Ning, Z. Y. [School of Physical Science and Technology, Suzhou University, SuZhou 215006 (China)

    2011-05-15

    The electron energy probability functions (EEPFs) were measured with increasing gas pressure in 60/13.56 MHz dual-frequency capacitively coupled plasma (DF-CCP) using compensated Langmiur electrostatic probe. The transition pressure of heating mode from collisionless to collisional heating in 60/13.56 MHz DF-CCP is found to be significantly lower than that in 13.56 MHz single-frequency CCP. As the pressure increases, the EEPFs change from bi-Maxwellian to Druyvesteyn type which is similar with that in 60 MHz single-frequency CCP. The pressure dependence of electron densities, effective electron temperatures, floating potentials, and plasma potentials in 60/13.56 MHz DF-CCP were measured and were compared with that in 60 MHz single-frequency CCP. The pressure dependence of these plasma parameters in 60/13.56 MHz DF-CCP is similar with that in 60 MHz single-frequency CCP.

  3. Direct current dielectric barrier assistant discharge to get homogeneous plasma in capacitive coupled discharge

    SciTech Connect (OSTI)

    Du, Yinchang; Li, Yangfang; Cao, Jinxiang; Liu, Yu; Wang, Jian; Zheng, Zhe

    2014-06-15

    In this paper, we propose a method to get more homogeneous plasma in the geometrically asymmetric capacitive coupled plasma (CCP) discharge. The dielectric barrier discharge (DBD) is used for the auxiliary discharge system to improve the homogeneity of the geometrically asymmetric CCP discharge. The single Langmuir probe measurement shows that the DBD can increase the electron density in the low density volume, where the DBD electrodes are mounted, when the pressure is higher than 5?Pa. By this manner, we are able to improve the homogeneity of the plasma production and increase the overall density in the target volume. At last, the finite element simulation results show that the DC bias, applied to the DBD electrodes, can increase the homogeneity of the electron density in the CCP discharge. The simulation results show a good agreement with the experiment results.

  4. Coupling of Kelvin-Helmholtz instability and buoyancy instability in a thermally laminar plasma

    SciTech Connect (OSTI)

    Ren Haijun; Wu Zhengwei [CAS Key Laboratory of Basic Plasma Physics, University of Science and Technology of China, Hefei 230026 (China); Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong); Cao Jintao; Dong Chao [CAS Key Laboratory of Basic Plasma Physics, University of Science and Technology of China, Hefei 230026 (China); Chu, Paul K. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong)

    2011-02-15

    Thermal convective instability is investigated in a thermally stratified plasma in the presence of shear flow, which is known to give rise to the Kelvin-Helmholtz (KH) instability. We examine how the KH instability and magnetothermal instability (MTI) affect each other. Based on the sharp boundary model, the KH instability coupled with the MTI is studied. We present the growth rate and instability criteria. The shear flow is shown to significantly alter the critical condition for the occurrence of thermal convective instability.

  5. Equation of state of strongly coupled quark--gluon plasma -- Path integral Monte Carlo results

    E-Print Network [OSTI]

    V. S. Filinov; M. Bonitz; Y. B. Ivanov; V. V. Skokov; P. R. Levashov; V. E. Fortov

    2009-05-04

    A strongly coupled plasma of quark and gluon quasiparticles at temperatures from $ 1.1 T_c$ to $3 T_c$ is studied by path integral Monte Carlo simulations. This method extends previous classical nonrelativistic simulations based on a color Coulomb interaction to the quantum regime. We present the equation of state and find good agreement with lattice results. Further, pair distribution functions and color correlation functions are computed indicating strong correlations and liquid-like behavior.

  6. Simple thermodynamics of strongly coupled one-component-plasma in two and three dimensions

    SciTech Connect (OSTI)

    Khrapak, Sergey A.; Khrapak, Alexey G.

    2014-10-15

    Simple analytical approximations for the internal energy of the strongly coupled one-component-plasma in two and three dimensions are discussed. As a result, new practical expressions for the internal energy in the fluid phase are proposed. Their accuracy is checked by evaluating the location of the fluid-solid phase transition from the free energy consideration. Possible applications to other related systems are briefly discussed.

  7. Positron impact excitations of hydrogen atom embedded in weakly coupled plasmas: Formation of Rydberg atoms

    SciTech Connect (OSTI)

    Rej, Pramit; Ghoshal, Arijit

    2014-09-15

    Formation of Rydberg atoms due to 1s?nlm excitations of hydrogen, for arbitrary n, l, m, by positron impact in weakly coupled plasma has been investigated using a distorted-wave theory in the momentum space. The interactions among the charged particles in the plasma have been represented by Debye-Huckel potentials. Making use of a simple variationally determined wave function for the hydrogen atom, it has been possible to obtain the distorted-wave scattering amplitude in a closed analytical form. A detailed study has been made on the effects of plasma screening on the differential and total cross sections in the energy range 20–300?eV of incident positron. For the unscreened case, our results agree nicely with some of the most accurate results available in the literature. To the best of our knowledge, such a study on the differential and total cross sections for 1s?nlm inelastic positron-hydrogen collisions for arbitrary n, l, m in weakly coupled plasmas is the first reported in the literature.

  8. Chaoticity threshold in magnetized plasmas: Numerical results in the weak coupling regime

    SciTech Connect (OSTI)

    Carati, A., E-mail: andrea.carati@unimi.it; Benfenati, F.; Maiocchi, A.; Galgani, L. [Università degli Studi di Milano, Milano (Italy)] [Università degli Studi di Milano, Milano (Italy); Zuin, M., E-mail: matteo.zuin@igi.cnr.it [Consorzio RFX, Associazione EURATOM-ENEA sulla Fusione, Padova (Italy)

    2014-03-15

    The present paper is a numerical counterpart to the theoretical work [Carati et al., Chaos 22, 033124 (2012)]. We are concerned with the transition from order to chaos in a one-component plasma (a system of point electrons with mutual Coulomb interactions, in a uniform neutralizing background), the plasma being immersed in a uniform stationary magnetic field. In the paper [Carati et al., Chaos 22, 033124 (2012)], it was predicted that a transition should take place when the electron density is increased or the field decreased in such a way that the ratio ?{sub p}/?{sub c} between plasma and cyclotron frequencies becomes of order 1, irrespective of the value of the so-called Coulomb coupling parameter ?. Here, we perform numerical computations for a first principles model of N point electrons in a periodic box, with mutual Coulomb interactions, using as a probe for chaoticity the time-autocorrelation function of magnetization. We consider two values of ? (0.04 and 0.016) in the weak coupling regime ????1, with N up to 512. A transition is found to occur for ?{sub p}/?{sub c} in the range between 0.25 and 2, in fairly good agreement with the theoretical prediction. These results might be of interest for the problem of the breakdown of plasma confinement in fusion machines.

  9. The Integrated Plasma Simulator: A Flexible Python Framework for Coupled Multiphysics Simulation

    SciTech Connect (OSTI)

    Foley, Samantha S [ORNL; Elwasif, Wael R [ORNL; Bernholdt, David E [ORNL

    2011-11-01

    High-fidelity coupled multiphysics simulations are an increasingly important aspect of computational science. In many domains, however, there has been very limited experience with simulations of this sort, therefore research in coupled multiphysics often requires computational frameworks with significant flexibility to respond to the changing directions of the physics and mathematics. This paper presents the Integrated Plasma Simulator (IPS), a framework designed for loosely coupled simulations of fusion plasmas. The IPS provides users with a simple component architecture into which a wide range of existing plasma physics codes can be inserted as components. Simulations can take advantage of multiple levels of parallelism supported in the IPS, and can be controlled by a high-level ``driver'' component, or by other coordination mechanisms, such as an asynchronous event service. We describe the requirements and design of the framework, and how they were implemented in the Python language. We also illustrate the flexibility of the framework by providing examples of different types of simulations that utilize various features of the IPS.

  10. Self-bias Dependence on Process Parameters in Asymmetric Cylindrical Coaxial Capacitively Coupled Plasma

    E-Print Network [OSTI]

    Upadhyay, J; Popovi?, S; Valente-Feliciano, A -M; Phillips, L; Vuškovi?, L

    2015-01-01

    An rf coaxial capacitively coupled Ar/Cl2 plasma is applied to processing the inner wall of superconducting radio frequency cavities. A dc self-bias potential is established across the inner electrode sheath due to the surface area difference between inner and outer electrodes of the coaxial plasma. The self-bias potential measurement is used as an indication of the plasma sheath voltage asymmetry. The understanding of the asymmetry in sheath voltage distribution in coaxial plasma is important for the modification of the inner surfaces of three dimensional objects. The plasma sheath voltages were tailored to process the outer wall by providing an additional dc current to the inner electrode with the help of an external dc power supply. The dc self-bias potential is measured for different diameter electrodes and its variation on process parameters such as gas pressure, rf power and percentage of chlorine in the Ar/Cl2 gas mixture is studied. The dc current needed to overcome the self-bias potential to make it ...

  11. Dynamics of compressional Mach cones in a strongly coupled complex plasma

    SciTech Connect (OSTI)

    Bandyopadhyay, P., E-mail: pintu@ipr.res.in; Dey, R.; Sen, Abhijit [Institute for Plasma Research, Bhat, Gandhinagar-382428 (India); Kadyan, Sangeeta [Department of Physics, Maharshi Dayanand University, Rohtak 124001 (India)

    2014-10-15

    Using a Generalised-Hydrodynamic (GH) fluid model, we study the influence of strong coupling induced modification of the fluid compressibility on the dynamics of compressional Mach cones in a dusty plasma medium. A significant structural change of lateral wakes for a given Mach number and Epstein drag force is found in the strongly coupled regime. With the increase of fluid compressibility, the peak amplitude of the normalised perturbed dust density first increases and then decreases monotonically after reaching its maximum value. It is also noticed that the opening angle of the cone structure decreases with the increase of the compressibility of the medium and the arm of the Mach cone breaks up into small structures in the velocity vector profile when the coupling between the dust particles increases.

  12. Theoretical study of head-on collision of dust acoustic solitary waves in a strongly coupled complex plasma

    SciTech Connect (OSTI)

    Jaiswal, S., E-mail: surabhi@ipr.res.in; Bandyopadhyay, P.; Sen, A. [Institute for Plasma Research, Bhat, Gandhinagar, Gujarat 382428 (India)

    2014-05-15

    We investigate the propagation characteristics of two counter propagating dust acoustic solitary waves (DASWs) undergoing a head-on collision, in the presence of strong coupling between micron sized charged dust particles in a complex plasma. A coupled set of nonlinear dynamical equations describing the evolution of the two DASWs using the extended Poincaré-Lighthill-Kuo perturbation technique is derived. The nature and extent of post collision phase-shifts of these solitary waves are studied over a wide range of dusty plasma parameters in a strongly and a weakly coupled medium. We find a significant change in the nature and amount of phase delay in the strongly coupled regime as compared to a weakly coupled regime. The phase shift is seen to change its sign beyond a threshold value of compressibility of the medium for a given set of dusty plasma parameters.

  13. Thermal plasma process for recovering monomers and high value carbons from polymeric materials

    DOE Patents [OSTI]

    Knight, Richard (Philadelphia, PA); Grossmann, Elihu D. (Narberth, PA); Guddeti, Ravikishan R. (Philadelphia, PA)

    2002-01-01

    The present invention relates to a method of recycling polymeric waste products into monomers and high value forms of carbon by pyrolytic conversion using an induction coupled RF plasma heated reactor.

  14. Final Scientific/Technical Report for "Strongly-Coupled Dusty Plasmas"

    SciTech Connect (OSTI)

    John Goree

    2010-08-14

    The subject of the project is the basic-plasma physics topic of strongly-coupled plasmas, as studied experimentally using dusty plasmas. This topic is highly interdisciplinary, with significant overlap with astrophysics, space physics, and condensed matter physics. Among the successes of this project during the most recent four-year period are the 23 papers were produced for peer-reviewed scientific journals. These papers mostly report experiments, as well as some numerical simulations. Coauthors of the papers include collaborators in Germany, Hungary, and Russia, as well as the U.S. Research topics included traditional plasma physics themes such as transport, waves, instabilities, and experimental diagnostics. They also included interdisciplinary topics of melting (condensed matter physics) and rarefied gas dynamics (fluid mechanics). All of the research topics were chosen to have a high impact. Our success in achieving a high impact is demonstrated by the seven papers published in Physical Review Letters over a four-year period, and a significant number of invited talks. The project included a broader-impact element that included not only training of graduate students and public dissemination of research results, but also an outreach program. The outreach Included presentations motivated by the sound-wave experiments in this project for the 'Family Science Adventures' (for children and parents of Iowa City area) and hands-on experiments at a K12 school (3rd and 4th grades in 2007, and 5th and 6th grades in 2008).

  15. Study of ICRF wave propagation and plasma coupling efficiency in a linear magnetic mirror device

    SciTech Connect (OSTI)

    Peng, S.Y.

    1991-07-01

    Ion Cyclotron Range of Frequency (ICRF) wave propagation in an inhomogeneous axial magnetic field in a cylindrical plasma-vacuum system has historically been inadequately modelled. Previous works either sacrifice the cylindrical geometry in favor of a simpler slab geometry, concentrate on the resonance region, use a single mode to represent the entire field structure, or examine only radial propagation. This thesis performs both analytical and computational studies to model the ICRF wave-plasma coupling and propagation problem. Experimental analysis is also conducted to compare experimental results with theoretical predictions. Both theoretical as well as experimental analysis are undertaken as part of the thesis. The theoretical studies simulate the propagation of ICRF waves in an axially inhomogeneous magnetic field and in cylindrical geometry. Two theoretical analysis are undertaken - an analytical study and a computational study. The analytical study treats the inhomogeneous magnetic field by transforming the (r,z) coordinate into another coordinate system ({rho},{xi}) that allows the solution of the fields with much simpler boundaries. The plasma fields are then Fourier transformed into two coupled convolution-integral equations which are then differenced and solved for both the perpendicular mode number {alpha} as well as the complete EM fields. The computational study involves a multiple eigenmode computational analysis of the fields that exist within the plasma-vacuum system. The inhomogeneous axial field is treated by dividing the geometry into a series of transverse axial slices and using a constant dielectric tensor in each individual slice. The slices are then connected by longitudinal boundary conditions.

  16. Analysis and design of resonant inductively coupled circuits : application to benefit denial solutions for the retail industry

    E-Print Network [OSTI]

    Rony, Amaury

    2013-01-01

    ProTeqt develops benefit denial solutions that are electromagnetically deactivated. A magnetic field from the deactivation tablet inductively heats an enabler that provides the proper force to disengage the locking mechanism. ...

  17. VOLUME 78, NUMBER 8 P H Y S I C A L R E V I E W L E T T E R S 24 FEBRUARY 1997 Debye Shielding and Particle Correlations in Strongly Coupled Dusty Plasmas

    E-Print Network [OSTI]

    Otani, Niels F.

    in dusty plasma research, while fully aware that the dust particles are strongly coupled, have continued

  18. Drag force in strongly coupled, anisotropic plasma at finite chemical potential

    E-Print Network [OSTI]

    Somdeb Chakraborty; Najmul Haque

    2014-10-26

    We employ methods of gauge/string duality to analyze the drag force on a heavy quark moving through a strongly coupled, anisotropic \\mathcal{N}=4, SU(N) super Yang- Mills plasma in the presence of a finite U(1) chemical potential. We present numerical results valid for any value of the anisotropy parameter and the U(1) charge density and arbitrary direction of the quark velocity with respect to the direction of anisotropy. In the small anisotropy limit we are also able to furnish analytical results.

  19. The polarized Debye sheath effect on Kadomtsev-Petviashvili electrostatic structures in strongly coupled dusty plasma

    SciTech Connect (OSTI)

    Shahmansouri, M.; Alinejad, H.

    2015-04-15

    We give a theoretical investigation on the dynamics of nonlinear electrostatic waves in a strongly coupled dusty plasma with strong electrostatic interaction between dust grains in the presence of the polarization force (i.e., the force due to the polarized Debye sheath). Adopting a reductive perturbation method, we derived a three-dimensional Kadomtsev-Petviashvili equation that describes the evolution of weakly nonlinear electrostatic localized waves. The energy integral equation is used to study the existence domains of the localized structures. The analysis provides the localized structure existence region, in terms of the effects of strong interaction between the dust particles and polarization force.

  20. Kelvin-Helmholtz instability in a strongly coupled dusty plasma medium

    SciTech Connect (OSTI)

    Tiwari, Sanat Kumar; Das, Amita; Patel, Bhavesh G. [Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India); Angom, Dilip [Physical Research Laboratory, Ahmedabad 380 009 (India); Kaw, Predhiman [Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India); Physical Research Laboratory, Ahmedabad 380 009 (India)

    2012-07-15

    The Kelvin-Helmholtz (KH) instability in the context of strongly coupled dusty plasma medium has been investigated. In particular, the role of transverse shear and the compressional acoustic modes in both the linear and nonlinear regimes of the KH instability has been studied. It is observed that in addition to the conventional nonlocal KH instability, there exists a local instability in the strong coupling case. The interplay of the KH mode with this local instability shows up in the simulations as an interesting phenomenon of recurrence in the nonlinear regime. Thus, a cyclic KH instability process is observed to occur. These cyclic events are associated with bursts of activity in terms of transverse and compressional wave generation in the medium.

  1. Doubly fed induction machine

    DOE Patents [OSTI]

    Skeist, S. Merrill; Baker, Richard H.

    2005-10-11

    An electro-mechanical energy conversion system coupled between an energy source and an energy load including an energy converter device having a doubly fed induction machine coupled between the energy source and the energy load to convert the energy from the energy source and to transfer the converted energy to the energy load and an energy transfer multiplexer coupled to the energy converter device to control the flow of power or energy through the doubly fed induction machine.

  2. Multi-chord fiber-coupled interferometry of supersonic plasma jets andcomparisons with synthetic data

    SciTech Connect (OSTI)

    Merritt, Elizabeth C.; Lynn, Alan G.; Gilmore, Mark A.; Thoma, Carsten; Loverich, John; Hsu, Scott C.

    2012-05-03

    A multi-chord fiber-coupled interferometer [Merritt et al., Rev. Sci. Instrum. 83, 033506 (2012)] is being used to make time-resolved density measurements of supersonic argon plasma jets on the Plasma Liner Experiment [Hsu et al., Bull. Amer. Phys. Soc. 56, 307 (2011)]. The long coherence length of the laser (> 10 m) allows signal and reference path lengths to be mismatched by many meters without signal degradation, making for a greatly simplified optical layout. Measured interferometry phase shifts are consistent with a partially ionized plasma in which an initially positive phase shift becomes negative when the ionization fraction drops below a certain threshold. In this case, both free electrons and bound electrons in ions and neutral atoms contribute to the index of refraction. This paper illustrates how the interferometry data, aided by numerical modeling, are used to derive total jet density, jet propagation velocity ({approx} 15-50 km/s), jet length ({approx} 20-100 cm), and 3D expansion.

  3. Effects of the Running of the QCD Coupling on the Energy Loss in the Quark-Gluon Plasma

    E-Print Network [OSTI]

    Jens Braun; Hans-Jürgen Pirner

    2006-10-25

    Finite temperature modifies the running of the QCD coupling alpha_s(k,T) with resolution k. After calculating the thermal quark and gluon masses selfconsistently, we determine the quark-quark and quark-gluon cross sections in the plasma based on the running coupling. We find that the running coupling enhances these cross sections by factors of two to four depending on the temperature. We also compute the energy loss dE/dx of a high-energy quark in the plasma as a function of temperature. Our study suggests that, beside t-channel processes, inverse Compton scattering is a relevant process for a quantitative understanding of the energy loss of an incident quark in a hot plasma.

  4. N-body Lyapunov expansion rates in one component strongly coupled plasmas

    SciTech Connect (OSTI)

    Ueshima, Y.; Nishihara, K.; Barnett, D.M.; Tajima, T.; Furukawa, H. [Institute of Laser Engineering, Osaka University, Suita, Osaka 565 (Japan)

    1996-05-01

    Phase space Lyapunov expansion rates are measured for the first time for Coulomb many body systems with the use of a 3-{ital d} particle code. The time averaged Lyapunov exponents, {lambda}/{omega}{sub {ital p}}, are found to be proportional to {Gamma}{sup {minus}2/5} and the cubic root of the diffusion coefficient in the range of 1{lt}{Gamma}{lt}160, where {omega}{sub {ital p}} and {Gamma} are plasma frequency and ion coupling constant, respectively. A large jump of the averaged Lyapunov exponent is observed near {Gamma}{approximately}170, corresponding to the phase transition from liquid to solid. Instantaneous Lyapunov exponent has chaotic behavior and consists of three different spectra, flat, {ital f}{sup {minus}2} and {ital f}{sup {minus}1}. {copyright} {ital 1996 American Institute of Physics.}

  5. Energy loss, equilibration, and thermodynamics of a baryon rich strongly coupled quark-gluon plasma

    E-Print Network [OSTI]

    Rougemont, Romulo; Finazzo, Stefano; Noronha, Jorge

    2015-01-01

    Lattice data for the QCD equation of state and the baryon susceptibility near the crossover phase transition (at zero baryon density) are used to determine the input parameters of a 5-dimensional Einstein-Maxwell-Dilaton holographic model that provides a consistent holographic framework to study both equilibrium and out-of-equilibrium properties of a hot and {\\it baryon rich} strongly coupled quark-gluon plasma (QGP). We compare our holographic equation of state computed at nonzero baryon chemical potential, $\\mu_B$, with recent lattice calculations and find quantitative agreement for the pressure and the speed of sound for $\\mu_B \\leq 400$ MeV. This holographic model is used to obtain holographic predictions for the temperature and $\\mu_B$ dependence of the drag force and the Langevin diffusion coefficients associated with heavy quark jet propagation as well as the jet quenching parameter $\\hat{q}$ and the shooting string energy loss of light quarks in the dense plasma. We find that the energy loss of heavy ...

  6. Velocity Dependence of Baryon Screening in a Hot Strongly Coupled Plasma

    E-Print Network [OSTI]

    Christiana Athanasiou; Hong Liu; Krishna Rajagopal

    2008-05-12

    The L-dependence of the static potential between Nc quarks arranged in a circle of radius L (a "baryon") immersed in the hot plasma of a gauge theory with Nc colors defines a screening length Ls. We use the AdS/CFT correspondence to compute this screening length for the case of heavy quarks in the plasma of strongly coupled N=4 super Yang-Mills theory moving with velocity v relative to the baryon. We find that in the v -> 1 limit, Ls \\propto (1-v^2)^{1/4}/T, and find that corrections to this velocity dependence are small at lower velocities. This result provides evidence for the robustness of the analogous behavior of the screening length defined by the static quark-antiquark pair, which has been computed previously and in QCD is relevant to quarkonium physics in heavy ion collisions. Our results also show that as long as the hot wind is not blowing precisely perpendicular to the plane of the baryon configuration that we analyze, the Nc different quarks are not all affected by the wind velocity to the same degree, with those quarks lying perpendicular to the wind direction screened most effectively.

  7. Particle simulation of Lyapunov exponents in one-component strongly coupled plasmas

    SciTech Connect (OSTI)

    Ueshima, Y.; Nishihara, K. [Institute of Laser Engineering, Osaka University, Suita, Osaka 565 (Japan)] [Institute of Laser Engineering, Osaka University, Suita, Osaka 565 (Japan); Barnett, D.M.; Tajima, T. [Fusion Studies, University of Texas at Austin, Austin, Texas 78712 (United States)] [Fusion Studies, University of Texas at Austin, Austin, Texas 78712 (United States); Furukawa, H. [Institute for Laser Technology, Suita, Osaka 565 (Japan)] [Institute for Laser Technology, Suita, Osaka 565 (Japan)

    1997-03-01

    The Lyapunov exponents and instantaneous expansion rates in a phase space of Coulomb many-body systems are measured with the use of a three-dimensional particle code SCOPE [K. Nishihara, Kakuyugo Kenkyu {bold 66}, 253 (1991)]. The code calculates particle dynamics determined by Coulomb forces among individual particles. The Lyapunov exponents normalized by plasma frequency are found to be proportional to {Gamma}{sup {minus}2/5} in the range of 1{le}{Gamma}{le}160, where {Gamma} is the Coulomb coupling constant of the ion one-component plasma. There is a large jump of the Lyapunov exponent near {Gamma}{approximately}170, which corresponds to the phase transition from the liquid to the solid state in the one-component plasma. In the solid state, the normalized Lyapunov exponents are proportional to {Gamma}{sup {minus}6/5} for 170{lt}{Gamma}{lt}300. The observed dependence is discussed in analogy to a rigid-body particle system and a weakly nonlinear lattice system for liquid and solid states, respectively. Diffusion coefficients are found to be proportional to the third power of the Lyapunov exponent in the liquid state, that is, for 1{le}{Gamma}{le}160. These results imply that the Lyapunov exponent is in close relation to the transport processes. The instantaneous expansion rate starts from a small value and increases rapidly to a large peak value before declining slowly towards an asymptotic value. This stage is called the Lyapunov transient stage. Products of the transient time and the Lyapunov exponent are found to be 1.5{endash}2. Information of the initial state is lost after the transient time. The chaotic behavior of the instantaneous expansion rate is also shown. {copyright} {ital 1997} {ital The American Physical Society}

  8. Plasma Phys. Conhol. Fusion 36 (1994) 1391-1406. Printed in the UK An investigationof coupled energyand particletransportin

    E-Print Network [OSTI]

    Bishop, Christopher M.

    1994-01-01

    and energy ansport in tokamak plasmas and presents analytical and numerical investigations of this type of transport. This coupling generally leads to discrepancies between the effective thermal diffusivities lead to small apparent perturbations of the density, when the energy balance is perturbed, whilst still

  9. The effect of magnetic field on bistability in 1D photonic crystal doped by magnetized plasma and coupled nonlinear defects

    SciTech Connect (OSTI)

    Mehdian, H.; Mohammadzahery, Z.; Hasanbeigi, A. [Department of Physics and Institute for Plasma Research, Kharazmi University, 49 Dr Mofatteh Avenue, Tehran 15614 (Iran, Islamic Republic of)] [Department of Physics and Institute for Plasma Research, Kharazmi University, 49 Dr Mofatteh Avenue, Tehran 15614 (Iran, Islamic Republic of)

    2014-01-15

    In this work, we study the defect mode and bistability behavior of 1-D photonic band gap structure with magnetized plasma and coupled nonlinear defects. The transfer matrix method has been employed to investigate the magnetic field effect on defect mode frequency and bistability threshold. The obtained results show that the frequency of defect mode and bistability threshold can be altered, without changing the structure of the photonic multilayer. Therefore, the bistability behavior of the subjected structure in the presence of magnetized plasma can be utilized in manufacturing wide frequency range devices.

  10. Spectroscopy diagnostic of dual-frequency capacitively coupled CHF{sub 3}/Ar plasma

    SciTech Connect (OSTI)

    Liu, Wen-Yao; Du, Yong-Quan [Laboratory of Plasma Physical Chemistry, Dalian University of Technology, Dalian 116024 (China)] [Laboratory of Plasma Physical Chemistry, Dalian University of Technology, Dalian 116024 (China); Liu, Yong-Xin; Liu, Jia; Zhao, Tian-Liang; Wang, You-Nian [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)] [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Xu, Yong; Li, Xiao-Song; Zhu, Ai-Min [Laboratory of Plasma Physical Chemistry, Dalian University of Technology, Dalian 116024 (China) [Laboratory of Plasma Physical Chemistry, Dalian University of Technology, Dalian 116024 (China); School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)

    2013-11-15

    A combined spectroscopic method of absorption, actinometry, and relative optical emission intensity is employed to determine the absolute CF{sub 2} density, the relative F and H densities, H atom excitation temperature and the electron density in dual-frequency (60/2 MHz) capacitively coupled CHF{sub 3}/Ar plasmas. The effects of different control parameters, such as high-frequency (HF) power, low-frequency (LF) power, gas pressure, gap length and content of CHF{sub 3}, on the concentration of radical CF{sub 2}, F, and H and excitation temperature are discussed, respectively. It is found that the concentration of CF{sub 2} is strongly dependent on the HF power, operating pressure and the proportion of CHF{sub 3} in feed gas, while it is almost independent of the LF power and the gap length. A higher concentration ratio of F to CF{sub 2} could be obtained in dual-frequency discharge case. Finally, the generation and decay mechanisms of CF{sub 2} and F were also discussed.

  11. Influence of microwave driver coupling design on plasma density at Testbench for Ion sources Plasma Studies, a 2.45 GHz Electron Cyclotron Resonance Plasma Reactor

    SciTech Connect (OSTI)

    Megía-Macías, A.; Vizcaíno-de-Julián, A. [E.S.S. Bilbao, Edificio Cosimet, Landabarri 2, 48940-Leioa, Vizcaya (Spain)] [E.S.S. Bilbao, Edificio Cosimet, Landabarri 2, 48940-Leioa, Vizcaya (Spain); Cortázar, O. D., E-mail: dcortazar@essbilbao.org [E.S.S. Bilbao, Edificio Cosimet, Landabarri 2, 48940-Leioa, Vizcaya (Spain); Universidad de Castilla-La Mancha, ETSII, C.J. Cela s/n, 13170 Ciudad Real (Spain)

    2014-03-15

    A comparative study of two microwave driver systems (preliminary and optimized) for a 2.45 GHz hydrogen Electron Cyclotron Resonance plasma generator has been conducted. The influence on plasma behavior and parameters of stationary electric field distribution in vacuum, i.e., just before breakdown, along all the microwave excitation system is analyzed. 3D simulations of resonant stationary electric field distributions, 2D simulations of external magnetic field mapping, experimental measurements of incoming and reflected power, and electron temperature and density along the plasma chamber axis have been carried out. By using these tools, an optimized set of plasma chamber and microwave coupler has been designed paying special attention to the optimization of stationary electric field value in the center of the plasma chamber. This system shows a strong stability on plasma behavior allowing a wider range of operational parameters and even sustaining low density plasma formation without external magnetic field. In addition, the optimized system shows the capability to produce values of plasma density four times higher than the preliminary as a consequence of a deeper penetration of the magnetic resonance surface in relative high electric field zone by keeping plasma stability. The increment of the amount of resonance surface embedded in the plasma under high electric field is suggested as a key factor.

  12. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 39, NO. 12, DECEMBER 2011 3307 Microwave-Plasma-Coupled Re-Ignition of

    E-Print Network [OSTI]

    Lee, Tonghun

    , improved fuel efficiency through more complete combustion, reduction of pollution by altering oxidation by-assisted ig- nition and combustion research works. Results indicate that, for re-ignition to occur-ignition to occur. Index Terms--Auto-ignition temperature, laser induced fluores- cence, plasma assisted combustion

  13. Extraction of negative ions from pulsed electronegative inductively coupled plasmas having a radio-frequency substrate bias

    E-Print Network [OSTI]

    Kushner, Mark

    of Illinois, 1406 W. Green Street, Urbana, Illinois 61801 Mark J. Kushnerb) Department of Electrical and Computer Engineering, University of Illinois, 1406 W. Green Street, Urbana, Illinois 61801 Received 5 with an anisotropic angular distribution due to more favorable sheath formation. © 2004 American Vacuum Society. DOI

  14. The determination of sulfur-containing surfactants with a high pressure liquid chromatography-inductively coupled plasma emission spectrometry system 

    E-Print Network [OSTI]

    Hobill, Jonathan Edward

    1987-01-01

    and standard millivolt intensities 81 20 Detection limits for nickel calculated by using the blank and standard millivolt intensities 82 Detection limits of sulfur in methanol/water (411 v/v) matrix. . . . . . . . . . . . . . 85 22 Detection limits of sulfur... data from the PDP 11/03 to the PDP 11/44 and Z-8 computers). 100 DZM M(48) ID(48) IF(5) 105 REM DZM MZLLZVOLT ZNTES1TIES (M), INSTRUMENT PARAMETERS (D) AND 106 REM PZLE NAME FOR DATA STORAGE (F) 220 SENDS (5) 222 REM SEND TO ll/44 230 PRINT "RUN...

  15. Nanofabrication of sharp diamond tips by e-beam lithography and inductively coupled plasma reactive ion etching.

    SciTech Connect (OSTI)

    Moldovan, N.; Divan, R.; Zeng, H.; Carlisle, J. A.; Advanced Diamond Tech.

    2009-12-07

    Ultrasharp diamond tips make excellent atomic force microscopy probes, field emitters, and abrasive articles due to diamond's outstanding physical properties, i.e., hardness, low friction coefficient, low work function, and toughness. Sharp diamond tips are currently fabricated as individual tips or arrays by three principal methods: (1) focused ion beam milling and gluing onto a cantilever of individual diamond tips, (2) coating silicon tips with diamond films, or (3) molding diamond into grooves etched in a sacrificial substrate, bonding the sacrificial substrate to another substrate or electrodepositing of a handling chip, followed by dissolution of the sacrificial substrate. The first method is tedious and serial in nature but does produce very sharp tips, the second method results in tips whose radius is limited by the thickness of the diamond coating, while the third method involves a costly bonding and release process and difficulties in thoroughly filling the high aspect ratio apex of molding grooves with diamond at the nanoscale. To overcome the difficulties with these existing methods, this article reports on the feasibility of the fabrication of sharp diamond tips by direct etching of ultrananocrystalline diamond (UNCD{reg_sign}) as a starting and structural material. The UNCD is reactive ion etched using a cap-precursor-mask scheme. An optimized etching recipe demonstrates the formation of ultrasharp diamond tips ({approx} 10 nm tip radius) with etch rates of 650 nm/min.

  16. FIRST STEP IN THEORETICAL APPROACH IN STUDY OF MARS AND TITAN ATMOSPHERES WITH AN INDUCTIVELY COUPLED PLASMA TORCH

    E-Print Network [OSTI]

    with the titan atmosphere (CH4-N2) unlike the Mars atmosphere (CO2-N2). We observe the creation of solid], one can obtain the molar fraction versus temperature. The composition of Mars is assumed to be 97% CO22, CO2 - , N2O, N2O3, N2O4, N2O5, N2O+, N3, NCN, NO2, NO2 - , NO3, O3 and the electrons

  17. Photon noise from chaotic and coherent millimeter-wave sources measured with horn-coupled, aluminum lumped-element kinetic inductance detectors

    E-Print Network [OSTI]

    Flanigan, Daniel; Jones, Glenn; Johnson, Bradley R; Ade, Peter; Araujo, Derek; Bradford, Kristi; Cantor, Robin; Che, George; Day, Peter K; Doyle, Simon; Kjellstrand, Carl Bjorn; LeDuc, Henry G; Limon, Michele; Luu, Vy; Mauskopf, Philip; Miller, Amber; Mroczkowski, Tony; Tucker, Carole; Zmuidzinas, Jonas

    2015-01-01

    We report photon-noise limited performance of horn-coupled, aluminum lumped-element kinetic inductance detectors at millimeter wavelengths. The detectors are illuminated by a millimeter-wave source that uses an active multiplier chain to produce radiation between 140 and 160 GHz. We feed the multiplier with either amplified broadband noise or a continuous-wave tone from a microwave signal generator. We demonstrate that the detector response over a 40 dB range of source power is well-described by a simple model that considers the number of quasiparticles. The detector noise-equivalent power (NEP) is dominated by photon noise when the absorbed power is greater than approximately 1 pW, which corresponds to $\\mathrm{NEP} \\approx 2 \\times 10^{-17} \\; \\mathrm{W} \\; \\mathrm{Hz}^{-1/2}$, referenced to absorbed power. At higher source power levels we observe the relationships between noise and power expected from the photon statistics of the source signal: $\\mathrm{NEP} \\propto P$ for broadband (chaotic) illumination ...

  18. One-dimensional hybrid simulation of the dc/RF combined driven capacitively coupled CF{sub 4} plasmas

    SciTech Connect (OSTI)

    Wang Shuai [School of Science, Northeastern University, Shenyang 110891 (China); Xu Xiang; Wang Younian [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)

    2012-11-15

    We developed a one-dimensional hybrid model to simulate the dc/RF combined driven capacitively coupled plasma for CF{sub 4} discharges. The numerical results show the influence of the dc source on the plasma density distribution, ion energy distributions (IEDs), and ion angle distributions (IADs) on both RF and dc electrodes. The increase of dc voltage impels more ions with high energy to the electrode applied to the dc source, which makes the IEDs at the dc electrode shift toward higher energy and the peaks in IADs shift toward the small angle region. At the same time, it also decreases ion-energy at the RF electrode and enlarges the ion-angles which strike the RF electrode.

  19. Precocious suppression of baryon diffusion and transport in a baryon rich strongly coupled quark-gluon plasma

    E-Print Network [OSTI]

    Rougemont, Romulo

    2015-01-01

    Five dimensional black hole solutions that describe the QCD crossover transition seen in (2+1)-flavor lattice QCD calculations at nonzero baryon densities are used to obtain predictions for the baryon susceptibility, baryon conductivity, baryon diffusion constant, and thermal conductivity of the strongly coupled quark-gluon plasma in the range of temperatures $T=130-300$ MeV and baryon chemical potentials $\\mu_B=0-400$ MeV. Diffusive transport is predicted to be already suppressed in this region of the QCD phase diagram in a way that is consistent with the existence of a critical end point at larger baryon densities.

  20. Effect of bulk electric field reversal on the bounce resonance heating in dual-frequency capacitively coupled electronegative plasmas

    SciTech Connect (OSTI)

    Liu Yongxin; Zhang Quanzhi; Liu Jia; Song Yuanhong; Wang Younian [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Bogaerts, Annemie [Department of Chemistry, University of Antwerp, Campus Drie Eiken, Universiteitsplein 1, BE-2610 Wilrijk-Antwerp (Belgium)

    2012-09-10

    The electron bounce resonance heating (BRH) in dual-frequency capacitively coupled plasmas operated in oxygen and argon has been studied by different experimental methods. In comparison with the electropositive argon discharge, the BRH in an electronegative discharge occurs at larger electrode gaps. Kinetic particle simulations reveal that in the oxygen discharge, the bulk electric field becomes quite strong and is out of phase with the sheath field. Therefore, it retards the resonant electrons when traversing the bulk, resulting in a suppressed BRH. This effect becomes more pronounced at lower high-frequency power, when the discharge mode changes from electropositive to electronegative.

  1. Pressure and arc voltage coupling in dc plasma torches: Identification and extraction of oscillation modes

    SciTech Connect (OSTI)

    Rat, V.; Coudert, J. F.

    2010-08-15

    This work is devoted to the instabilities occurring in a plasma torch, such as those found in plasma spraying. These instabilities are responsible for a lack of reproducibility of coatings properties, especially in the case of suspension plasma spraying that is an innovative way to obtain thin coatings of submicron-sized particles. Strong Helmholtz oscillations are highlighted in the plasma flow and it is demonstrated that they overlap with different acoustic modes in addition with the more commonly admitted ''restrike'' mode, the later being due to rearcing events in the arc region. The instabilities occur in the arc voltage but it is experimentally shown in this paper that the pressure within the torch body presents the same kind of instabilities. Besides, a numerical filtering technique has been adapted to isolate the different instability components. The operating parameters of the plasma torch were varied in order to highlight their influence on the amplitude of the different modes, both for the arc voltage and the pressure.

  2. VELOCITY-SHEAR-INDUCED MODE COUPLING IN THE SOLAR ATMOSPHERE AND SOLAR WIND: IMPLICATIONS FOR PLASMA HEATING AND MHD TURBULENCE

    SciTech Connect (OSTI)

    Hollweg, Joseph V.; Chandran, Benjamin D. G.; Kaghashvili, Edisher Kh. E-mail: ekaghash@aer.com

    2013-06-01

    We analytically consider how velocity shear in the corona and solar wind can cause an initial Alfven wave to drive up other propagating signals. The process is similar to the familiar coupling into other modes induced by non-WKB refraction in an inhomogeneous plasma, except here the refraction is a consequence of velocity shear. We limit our discussion to a low-beta plasma, and ignore couplings into signals resembling the slow mode. If the initial Alfven wave is propagating nearly parallel to the background magnetic field, then the induced signals are mainly a forward-going (i.e., propagating in the same sense as the original Alfven wave) fast mode, and a driven signal propagating like a forward-going Alfven wave but polarized like the fast mode; both signals are compressive and subject to damping by the Landau resonance. For an initial Alfven wave propagating obliquely with respect to the magnetic field, the induced signals are mainly forward- and backward-going fast modes, and a driven signal propagating like a forward-going Alfven wave but polarized like the fast mode; these signals are all compressive and subject to damping by the Landau resonance. A backward-going Alfven wave, thought to be important in the development of MHD turbulence, is also produced, but it is very weak. However, we suggest that for oblique propagation of the initial Alfven wave the induced fast-polarized signal propagating like a forward-going Alfven wave may interact coherently with the initial Alfven wave and distort it at a strong-turbulence-like rate.

  3. Induction voidmeter

    DOE Patents [OSTI]

    Anderson, Thomas T. (Downers Grove, IL); Roop, Conard J. (Lockport, IL); Schmidt, Kenneth J. (Midlothian, IL); Brewer, John (Oak Lawn, IL)

    1986-01-01

    An induction voidmeter for detecting voids in a conductive fluid may comprise: a four arm bridge circuit having two adjustable circuit elements connected as opposite arms of said bridge circuit, an input branch, and an output branch; two induction coils, bifilarly wound together, connected as the remaining two opposing arms of said bridge circuit and positioned such that the conductive fluid passes through said coils; applying an AC excitation signal to said input branch; and detecting the output signal generated in response to said excitation signal across said output branch. The induction coils may be located outside or inside a non-magnetic pipe containing the conductive fluid.

  4. Induction voidmeter

    DOE Patents [OSTI]

    Anderson, T.T.; Roop, C.J.; Schmidt, K.J.; Brewer, J.

    1983-12-21

    An induction voidmeter for detecting voids in a conductive fluid may comprise: a four arm bridge circuit having two adjustable circuit elements connected as opposite arms of said bridge, an input branch, and an output branch; two induction coils, bifilarly wound together, connected as the remaining two opposing arms of said bridge circuit and positioned such that the conductive fluid passes through said coils; means for applying an AC excitation signal to said input branch; and means for detecting the output signal generated in response to said excitation signal across said output branch. The induction coils may be located outside or inside a non-magnetic pipe containing the conductive fluid.

  5. Coupling of ion temperature gradient and trapped electron modes in the presence of impurities in tokamak plasmas

    SciTech Connect (OSTI)

    Du, Huarong; Wang, Zheng-Xiong, E-mail: zxwang@dlut.edu.cn [MOE Key Laboratory of Materials Modification by Beams, School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)] [MOE Key Laboratory of Materials Modification by Beams, School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Dong, J. Q. [Institute for Fusion Theory and Simulation, Zhejiang University, Hangzhou 310027 (China) [Institute for Fusion Theory and Simulation, Zhejiang University, Hangzhou 310027 (China); Southwestern Institute of Physics, Chengdu 610041 (China); Liu, S. F. [School of Physics, Nankai University, Tianjin 300071 (China)] [School of Physics, Nankai University, Tianjin 300071 (China)

    2014-05-15

    The coupling of ion temperature gradient (ITG or ?{sub i}) mode and trapped electron mode (TEM) in the presence of impurity ions is numerically investigated in toroidal collisionless plasmas, using the gyrokinetic integral eigenmode equation. A framework for excitations of the ITG modes and TEMs with respect to their driving sources is formulated first, and then the roles of impurity ions played in are analyzed comprehensively. In particular, the characteristics of the ITG and TEM instabilities in the presence of impurity ions are emphasized for both strong and weak coupling (hybrid and coexistent) cases. It is found that the impurity ions with inwardly (outwardly) peaked density profiles have stabilizing (destabilizing) effects on the hybrid (namely the TE-ITG) modes in consistence with previous works. A new finding of this work is that the impurity ions have stabilizing effects on TEMs in small ?{sub i} (?{sub i}?1) regime regardless of peaking directions of their density profiles whereas the impurity ions with density gradient L{sub ez}=L{sub ne}/L{sub nz}>1 (L{sub ez}<1) destabilize (stabilize) the TEMs in large ?{sub i} (?{sub i}?1) regime. In addition, the dependences of the growth rate, real frequency, eigenmode structure, and wave spectrum on charge concentration, charge number, and mass of impurity ions are analyzed in detail. The necessity for taking impurity ion effects on the features of turbulence into account in future transport experimental data analyses is also discussed.

  6. Rapid Heating of a Strongly Coupled Plasma near the Solid-Liquid Phase Transition M. J. Jensen,1,* T. Hasegawa,1,2

    E-Print Network [OSTI]

    California at San Diego, University of

    Rapid Heating of a Strongly Coupled Plasma near the Solid-Liquid Phase Transition M. J. Jensen,1 phase transition. We observe an unexpected rapid heating of the 9 Be ions in the region of the predicted solid-liquid phase transition and show that this rapid heating is due to a very temperature

  7. Periodic patterning stem cells and induction of skin appendages: p-ERK-dependent mes-enchymal condensation is coupled with Turing mechanism to convert stripes to spots

    E-Print Network [OSTI]

    Maini, Philip K.

    ABSTRACTS 931 Periodic patterning stem cells and induction of skin appendages: p-ERK-dependent mes patterns remains unknown. Using the feather model, here we show ERK activity-dependent mesenchymal cell chemotaxis toward initial peaks is essential for completing pattern formation. Adding ERK inhibitors produced

  8. Polymer Chains and Baryons in a Strongly Coupled Quark-Gluon Plasma

    E-Print Network [OSTI]

    Jinfeng Liao; Edward V. Shuryak

    2005-11-03

    Recently there was a significant change of views on physical properties and underlying dynamics of Quark-Gluon Plasma at $T=170-350 MeV$, produced in heavy ion collisions at RHIC. Instead of being a gas of $q,g$ quasiparticles, a near-perfect liquid is observed. Also, precisely in this temperature interval, the interaction deduced from lattice studies is strong enough to support multiple binary bound states. This work is the first variational study of {\\em multibody} bound states. We will consider: (i) ``polymer chains'' of the type $\\bar q g g ..g q$; (ii) baryons $(qqq)$; (iii) closed (3-)chains of gluons $(ggg)$. We found that chains (i) form in exactly the same $T$ range as binary states, with the same binding {\\em per bond}. The binding and $T$-range for diquarks, baryons and closed 3-chains are also established. We point out that the presence of chains, or possibly even a chain network, may drastically change the transport properties of matter, such as charm diffusion or jet energy loss. We further suggest that it seems to exist only for $T=(1-1.5)T_c$ and thus there may be a ``latent period'' for charm/jet quenching in RHIC collisions, while matter cools down to such $T$.

  9. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 31, NO. 4, AUGUST 2003 495 Computational Study of Capacitively Coupled

    E-Print Network [OSTI]

    Raja, Laxminarayan L.

    of gas to form filamentary or arc plasmas. This phenomena is called the glow-to-arc transition. PressureIEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 31, NO. 4, AUGUST 2003 495 Computational Study collisionality of the HPG plasma results in significant discharge po- tential drop across the bulk plasma region

  10. Induction of electron injection and betatron oscillation in a plasma-waveguide-based laser wakefield accelerator by modification of waveguide structure

    SciTech Connect (OSTI)

    Ho, Y.-C.; Hung, T.-S.; Chen, W.-H. [Department of Physics, National Central University, Jhong-Li 320, Taiwan (China) [Department of Physics, National Central University, Jhong-Li 320, Taiwan (China); Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan (China); Jhou, J.-G. [Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan (China) [Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan (China); Department of Physics, National Taiwan University, Taipei 106, Taiwan (China); Qayyum, H.; Chen, S.-Y. [Department of Physics, National Central University, Jhong-Li 320, Taiwan (China) [Department of Physics, National Central University, Jhong-Li 320, Taiwan (China); Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan (China); Molecular Science and Technology Program, Taiwan International Graduate Program, Academia Sinica, Taipei 115, Taiwan (China); Chu, H.-H. [Department of Physics, National Central University, Jhong-Li 320, Taiwan (China)] [Department of Physics, National Central University, Jhong-Li 320, Taiwan (China); Lin, J.-Y. [Department of Physics, National Chung Cheng University, Chia-Yi 621, Taiwan (China)] [Department of Physics, National Chung Cheng University, Chia-Yi 621, Taiwan (China); Wang, J. [Department of Physics, National Central University, Jhong-Li 320, Taiwan (China) [Department of Physics, National Central University, Jhong-Li 320, Taiwan (China); Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan (China); Department of Physics, National Taiwan University, Taipei 106, Taiwan (China)

    2013-08-15

    By adding a transverse heater pulse into the axicon ignitor-heater scheme for producing a plasma waveguide, a variable three-dimensionally structured plasma waveguide can be fabricated. With this technique, electron injection in a plasma-waveguide-based laser wakefield accelerator was achieved and resulted in production of a quasi-monoenergetic electron beam. The injection was correlated with a section of expanding cross-section in the plasma waveguide. Moreover, the intensity of the X-ray beam produced by the electron bunch in betatron oscillation was greatly enhanced with a transversely shifted section in the plasma waveguide. The technique opens a route to a compact hard-X-ray pulse source.

  11. Solenoid-free Plasma Start-up in NSTX using Transient CHI

    SciTech Connect (OSTI)

    Raman, R; Jarboe, T; Nelson, B; Mueller, D; Soukhanovskii, V A

    2009-01-05

    Experiments in NSTX have now demonstrated the coupling of toroidal plasmas produced by the technique of Coaxial Helicity Injection (CHI) to inductive sustainment and ramp-up of the toroidal plasma current. In these discharges, the central Ohmic transformer was used to apply an inductive loop voltage to discharges with a toroidal current of about 100 kA created by CHI. The coupled discharges have ramped up to >700 kA and transitioned into an H-mode demonstrating compatibility of this startup method with conventional operation. The electron temperature in the coupled discharges reached over 800 eV and the resulting plasma had low inductance, which is preferred for long-pulse high performance discharges. These results from NSTX in combination with the previously obtained record 160 kA non-inductively-generated startup currents in an ST or tokamak in NSTX demonstrate that CHI is a viable solenoid-free plasma startup method for future STs and tokamaks.

  12. Effects of fast atoms and energy-dependent secondary electron emission yields in PIC/MCC simulations of capacitively coupled plasmas

    E-Print Network [OSTI]

    Derzsi, A; Schuengel, E; Donko, Z; Schulze, J

    2014-01-01

    In most PIC/MCC simulations of radio frequency capacitively coupled plasmas (CCPs) several simplifications are made: (i) fast neutrals are not traced, (ii) heavy particle induced excitation and ionization are neglected, (iii) secondary electron emission from boundary surfaces due to neutral particle impact is not taken into account, and (iv) the secondary electron emission coefficient is assumed to be constant, i.e. independent of the incident particle energy and the surface conditions. Here we question the validity of these simplifications under conditions typical for plasma processing applications. We study the effects of including fast neutrals and using realistic energy-dependent secondary electron emission coefficients for ions and fast neutrals in simulations of CCPs operated in argon at 13.56 MHz and at neutral gas pressures between 3 Pa and 100 Pa. We find a strong increase of the plasma density and the ion flux to the electrodes under most conditions, if these processes are included realistically in ...

  13. Low sidewall damage plasma etching using ICP-RIE with HBr chemistry of Si=SiGe

    E-Print Network [OSTI]

    beyond the expected limitation forecasted by the International Technology Roadmap for Semiconduc- tors:1:100). The combination of HBr process gas and very low substrate bias power (10 W) for inductively coupled plasma- junction bipolar transistors (HBT) make Si-based RITDs excellent candidates to extend the Si technology

  14. Plasma generation for controlled microwave-reflecting surfaces in plasma antennas

    SciTech Connect (OSTI)

    Bliokh, Yury P.; Felsteiner, Joshua; Slutsker, Yakov Z. [Physics Department, Technion-Israel Institute of Technology, 32000 Haifa (Israel)

    2014-04-28

    The idea of replacing metal antenna elements with equivalent plasma objects has long been of interest because of the possibility of switching the antenna on and off. In general, two kinds of designs have so far been reported: (a) Separate plasma “wires” which are thin glass tubes filled with gas, where plasma appears due to discharge inside. (b) Reflecting surfaces, consisting of tightly held plasma wires or specially designed large discharge devices with magnetic confinement. The main disadvantages of these antennas are either large weight and size or too irregular surfaces for proper reflection. To design a microwave plasma antenna in the most common radar wavelength range of 1–3?cm with a typical gain of 30?dB, a smooth plasma mirror having a 10–30?cm diameter and a proper curvature is required. The plasma density must be 10{sup 12}–10{sup 14}?cm{sup ?3} in order to exceed the critical density for the frequency of the electromagnetic wave. To achieve this we have used a ferromagnetic inductively coupled plasma (FICP) source, where a thin magnetic core of a large diameter is fully immersed in the plasma. In the present paper, we show a way to adapt the FICP source for creating a flat switchable microwave plasma mirror with an effective diameter of 30?cm. This mirror was tested as a microwave reflector and there was found no significant difference when compared with a copper plate having the same diameter.

  15. Steady-state inductive spheromak operation

    DOE Patents [OSTI]

    Janos, Alan C. (E. Windsor, NJ); Jardin, Stephen C. (Princeton, NJ); Yamada, Masaaki (Lawrenceville, NJ)

    1987-01-01

    The inductively formed spheromak plasma can be maintained in a highly stable and controlled fashion. Steady-state operation is obtained by forming the plasma in the linked mode, then oscillating the poloidal and toroidal fields such that they have different phases. Preferably, the poloidal and magnetic fields are 90.degree. out of phase.

  16. Measurement of vibrational, gas, and rotational temperatures of H{sub 2} (X{sup 1} {sigma}{sub g}{sup +}) in radio frequency inductive discharge plasma by multiplex coherent anti-Stokes Raman scattering spectroscopy technique

    SciTech Connect (OSTI)

    Shakhatov, V.A.; De Pascale, O.; Capitelli, M.; Hassouni, K.; Lombardi, G.; Gicquel, A.

    2005-02-01

    Translational, rotational, and vibrational temperatures of H{sub 2} in radio frequency inductive discharge plasmas at pressures and power release ranges, respectively, of 0.5-8 torr and 0.5-2 W/cm{sup 3} have been measured by using multiplex coherent anti-Stokes Raman scattering (CARS) spectroscopy. Computational codes have been developed to determine the rotational and vibrational temperatures and to analyze H{sub 2} CARS spectrum for nonequilibrium conditions. The results show a decrease of the vibrational temperature from 4250 to 2800 K by increasing the pressure from 0.5 to 8 torr and a corresponding increase of the rotational temperature from 525 to 750 K.

  17. Wave frequency dependence of H{sup -} ion production and extraction in a transformer coupled plasma H{sup -} ion source at SNU

    SciTech Connect (OSTI)

    An, Young Hwa; Cho, Won Hwi; Chung, Kyoung-Jae; Lee, Kern; Jang, Seung Bin; Lee, Seok-Geun; Hwang, Y. S. [Department of Nuclear Engineering, Seoul National University, Seoul 151-744 (Korea, Republic of)

    2012-02-15

    The effect of rf wave frequencies on the production of H{sup -} ion is investigated in a transformer coupled plasma H{sup -} ion source at Seoul National University. A Langmuir probe is installed to measure the plasma density and temperature, and these plasma parameters are correlated to the extracted H{sup -} beam currents at various frequencies. The Langmuir probe is also used to measure the density of H{sup -} ions at the ion source by generating photodetachment with an Nd:YAG laser. The extracted H{sup -} currents decrease to a minimum value until 13 MHz and then, increase as the driving frequency increases from 13 MHz while the relative H{sup -} population measured by photodetachment monotonically decreases as the driving rf frequency increases from 11 MHz to 15 MHz. A potential well formed at the extraction region at high frequencies of more than 13 MHz is considered responsible for the increased H{sup -} beam extraction even with a lower photodetachment signal. The variation in the driving rf frequency not only affects the density and temperature of the plasma but also modifies the plasma potential with the existence of a filtering magnetic field and consequently, influences the extracted H{sup -} current through the extraction as well as formation of H{sup -} ions.

  18. Inductive tuners for microwave driven discharge lamps

    DOE Patents [OSTI]

    Simpson, James E. (Gaithersburg, MD)

    1999-01-01

    An RF powered electrodeless lamp utilizing an inductive tuner in the waveguide which couples the RF power to the lamp cavity, for reducing reflected RF power and causing the lamp to operate efficiently.

  19. An Experimental Study of Waveguide Coupled Microwave Heating with Conventional Multicusp Negative Ion Source

    E-Print Network [OSTI]

    Komppula, J; Koivisto, H; Laulainen, J; Tarvainen, O

    2015-01-01

    Negative ion production with conventional multicusp plasma chambers utilizing 2.45 GHz microwave heating is demonstrated. The experimental results were obtained with the multicusp plasma chambers and extraction systems of the RFdriven RADIS ion source and the filament driven arc discharge ion source LIISA. A waveguide microwave coupling system, which is almost similar to the one used with the SILHI ion source, was used. The results demonstrate that at least one third of negative ion beam obtained with inductive RF-coupling (RADIS) or arc discharge (LIISA) can be achieved with 1 kW of 2.45 GHz microwave power in CW mode without any modification of the plasma chamber. The co-extracted electron to H^- ratio and the optimum pressure range were observed to be similar for both heating methods. The behaviour of the plasma implies that the energy transfer from the microwaves to the plasma electrons is mainly an off-resonance process.

  20. Non-ambipolar radio-frequency plasma electron source and systems and methods for generating electron beams

    DOE Patents [OSTI]

    Hershkowitz, Noah (Madison, WI); Longmier, Benjamin (Madison, WI); Baalrud, Scott (Madison, WI)

    2009-03-03

    An electron generating device extracts electrons, through an electron sheath, from plasma produced using RF fields. The electron sheath is located near a grounded ring at one end of a negatively biased conducting surface, which is normally a cylinder. Extracted electrons pass through the grounded ring in the presence of a steady state axial magnetic field. Sufficiently large magnetic fields and/or RF power into the plasma allow for helicon plasma generation. The ion loss area is sufficiently large compared to the electron loss area to allow for total non-ambipolar extraction of all electrons leaving the plasma. Voids in the negatively-biased conducting surface allow the time-varying magnetic fields provided by the antenna to inductively couple to the plasma within the conducting surface. The conducting surface acts as a Faraday shield, which reduces any time-varying electric fields from entering the conductive surface, i.e. blocks capacitive coupling between the antenna and the plasma.

  1. A double-plasma source of continuous bipolar ion-ion beam

    SciTech Connect (OSTI)

    Dudin, S. V.; Scientific Center of Physical Technologies, Svobody sq. 6, 61022 Kharkiv ; Rafalskyi, D. V.

    2013-01-21

    A double-plasma source capable of the generation of a continuous bipolar ion-ion beam is described. The quasi-neutral ion-ion flow to an extraction electrode is formed in the system containing primary inductively coupled plasma separated from a secondary plasma by an electrostatic grid-type filter. The total current of each ion species to the 250 mm diameter extraction electrode is about 80 mA; the electron current does not exceed 30% of the ion current. Method of positive/negative ion current ratio control is proposed, allowing the ion currents ratio variation in wide range.

  2. Standard test method for determination of impurities in plutonium: acid dissolution, ion exchange matrix separation, and inductively coupled plasma-atomic emission spectroscopic (ICP/AES) analysis

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    2003-01-01

    1.1 This specification covers blended uranium trioxide (UO3), U3O8, or mixtures of the two, powders that are intended for conversion into a sinterable uranium dioxide (UO2) powder by means of a direct reduction process. The UO2 powder product of the reduction process must meet the requirements of Specification C 753 and be suitable for subsequent UO2 pellet fabrication by pressing and sintering methods. This specification applies to uranium oxides with a 235U enrichment less than 5 %. 1.2 This specification includes chemical, physical, and test method requirements for uranium oxide powders as they relate to the suitability of the powder for storage, transportation, and direct reduction to UO2 powder. This specification is applicable to uranium oxide powders for such use from any source. 1.3 The scope of this specification does not comprehensively cover all provisions for preventing criticality accidents, for health and safety, or for shipping. Observance of this specification does not relieve the user of th...

  3. Standard operating procedure for the laboratory analysis of lead in paint, bulk dust, and soil by ultrasonic, acid digestion and inductively coupled plasma emission spectrometric measurement

    SciTech Connect (OSTI)

    Grohse, P.M.; Gutknecht, W.F.; Luk, K.K.; Wilson, B.M.; Van Hise, C.C.

    1997-09-01

    The details and performance of a simplified extraction procedure and analysis for three media are provided. Paint, bulk dust, and soil are collected using standard or referenced methods. Up to 0.25 g of paint, bulk dust, or soil weighted out and placed in a 50-mL centrifuge tube. Five mL of 25% (v/v) nitric acid is added and the sample is ultrasonicated for 30 minutes.

  4. Effects of obliqueness and strong electrostatic interaction on linear and nonlinear propagation of dust-acoustic waves in a magnetized strongly coupled dusty plasma

    SciTech Connect (OSTI)

    Shahmansouri, M. [Department of Physics, Faculty of Science, Arak University, Arak 38156- 8 8349 (Iran, Islamic Republic of)] [Department of Physics, Faculty of Science, Arak University, Arak 38156- 8 8349 (Iran, Islamic Republic of); Mamun, A. A. [Department of Physics, Jahangirnagar University, Savar, Dhaka-1342 (Bangladesh)] [Department of Physics, Jahangirnagar University, Savar, Dhaka-1342 (Bangladesh)

    2014-03-15

    Linear and nonlinear propagation of dust-acoustic waves in a magnetized strongly coupled dusty plasma is theoretically investigated. The normal mode analysis (reductive perturbation method) is employed to investigate the role of ambient/external magnetic field, obliqueness, and effective electrostatic dust-temperature in modifying the properties of linear (nonlinear) dust-acoustic waves propagating in such a strongly coupled dusty plasma. The effective electrostatic dust-temperature, which arises from strong electrostatic interactions among highly charged dust, is considered as a dynamical variable. The linear dispersion relation (describing the linear propagation characteristics) for the obliquely propagating dust-acoustic waves is derived and analyzed. On the other hand, the Korteweg-de Vries equation describing the nonlinear propagation of the dust-acoustic waves (particularly, propagation of dust-acoustic solitary waves) is derived and solved. It is shown that the combined effects of obliqueness, magnitude of the ambient/external magnetic field, and effective electrostatic dust-temperature significantly modify the basic properties of linear and nonlinear dust-acoustic waves. The results of this work are compared with those observed by some laboratory experiments.

  5. Modelling of arc jet plasma flow in transitional regime by Navier Stokes and state-to-state coupling

    SciTech Connect (OSTI)

    Alexandrova, T.; Izrar, B.; Lino da Silva, M.; Dudeck, M.

    2005-05-16

    The combination of 2D Navier-Stokes and state-to-state approaches has been used to describe the air plasma flow in an arc-jet. The gas dynamic parameters were calculated in Navier-Stokes approximation in a steady state description without chemical reaction and vibrational exchanges. And then, the set of equations of vibrational level densities and atomic species densities was locally solved. Experimental validations have been performed.

  6. Inductive Wireless Power Transfer for RFID & Embedded Devices: Coil Misalignment Analysis and Design 

    E-Print Network [OSTI]

    Fotopoulou, Kyriaki

    2008-01-01

    Radio frequency inductive coupling is extensively employed for wireless powering of embedded devices such as low power passive near-field RFID systems and implanted sensors. The efficiency of low power inductive links ...

  7. Non-carbon induction furnace

    DOE Patents [OSTI]

    Holcombe, C.E.; Masters, D.R.; Pfeiler, W.A.

    1984-01-06

    The present invention is directed to an induction furnace for melting and casting highly pure metals and alloys such as uranium and uranium alloys in such a manner as to minimize contamination of the melt by carbon derived from the materials and the environment within the furnace. The subject furnace is constructed of non-carbon materials and is housed within a conventional vacuum chamber. The furnace comprises a ceramic oxide crucible for holding the charge of metal or alloys. The heating of the crucible is achieved by a plasma-sprayed tungsten susceptor surrounding the crucible which, in turn, is heated by an rf induction coil separated from the susceptor by a cylinder of inorganic insulation. The furnace of the present invention is capable of being rapidly cycled from ambient temperatures to about 1650/sup 0/C for effectively melting uranium and uranium alloys without the attendant carbon contamination problems previously encountered when using carbon-bearing furnace materials.

  8. Carbon-free induction furnace

    DOE Patents [OSTI]

    Holcombe, Cressie E. (Knoxville, TN); Masters, David R. (Knoxville, TN); Pfeiler, William A. (Norris, TN)

    1985-01-01

    An induction furnace for melting and casting highly pure metals and alloys such as uranium and uranium alloys in such a manner as to minimize contamination of the melt by carbon derived from the materials and the environment within the furnace. The subject furnace is constructed of carbon free materials and is housed within a conventional vacuum chamber. The furnace comprises a ceramic oxide crucible for holding the charge of metal or alloy. The heating of the crucible is achieved by a plasma-sprayed tungsten susceptor surrounding the crucible which, in turn, is heated by an RF induction coil separated from the susceptor by a cylinder of inorganic insulation. The furnace of the present invention is capable of being rapidly cycled from ambient temperatures to about 1650.degree. C. for effectively melting uranium and uranium alloys without the attendant carbon contamination problems previously encountered when using carbon-bearing furnace materials.

  9. Steady-state inductive spheromak operation

    DOE Patents [OSTI]

    Janos, A.C.; Jardin, S.C.; Yamada, M.

    1985-02-20

    The inductively formed spheromak configuration (S-1) can be maintained in a highly stable and controlled fashion. The method described eliminates the restriction to pulsed spheromak plasmas or the use of electrodes for steady-state operation, and, therefore, is a reactor-relevant formation and sustainment method.

  10. Models of radiofrequency coupling for negative ion sources

    SciTech Connect (OSTI)

    Cavenago, M.; Petrenko, S. [INFN-LNL, viale dell'Universita n.2, 35020 Legnaro (Italy)

    2012-02-15

    Radiofrequency heating for ICP (inductively coupled plasma) ion sources depends on the source operating pressure, the presence or absence of a Faraday shield, the driver coil geometry, the frequency used, and the magnetic field configuration: in negative ion source a magnetic filter seems necessary for H{sup -} survival. The result of single particle simulations showing the possibility of electron acceleration in the preglow regime and for reasonable driver chamber radius (15 cm) is reported, also as a function of the static external magnetic field. An effective plasma conductivity, depending not only from electron density, temperature, and rf field but also on static magnetic field is here presented and compared to previous models. Use of this conductivity and of multiphysics tools for a plasma transport and heating model is shown and discussed for a small source.

  11. Computer Science Induction to

    E-Print Network [OSTI]

    Berger, Ulrich

    Computer Science Induction to Postgraduate Research Studies Ulrich Berger Head of Postgraduate Research Supervision Regulations Progression Regulations Computer Science Induction to Postgraduate Research Studies Ulrich Berger Head of Postgraduate Research Department of Computer Science Swansea

  12. Plasma sweeper. [Patents

    DOE Patents [OSTI]

    Motley, R.W.; Glanz, J.

    1982-10-25

    A device is described for coupling RF power (a plasma sweeper) from RF power introducing means to a plasma having a magnetic field associated therewith comprises at least one electrode positioned near the plasma and near the RF power introducing means. Means are described for generating a static electric field at the electrode directed into the plasma and having a component substantially perpendicular to the plasma magnetic field such that a non-zero vector cross-product of the electric and magnetic fields exerts a force on the plasma causing the plasma to drift.

  13. Deuterium fusion through nonequilibrium induction

    SciTech Connect (OSTI)

    Fang, P.H. )

    1991-03-01

    This paper presents a deuterium fusion system that is based on the induction of fusion through a nonequilibrium thermodynamical configuration. Mechanical excitation using ultrasound is applied to a palladium electrode with deuterium-containing liquid, a mixture of palladium powder and deuterium-containing liquid, and a system of palladium and a highly compressed deuterium gas that approximates a deuterium solid. The ultrasound, when coupled with the medium of these systems, instantaneously creates a high temperature and pressure that would induce fusion between deuterons.

  14. Twenty Five Years of Vibrational Kinetics and Negative Ion Production in H2 Plasmas: Modelling Aspects

    SciTech Connect (OSTI)

    Capitelli, M.; De Pascale, O.; Diomede, P.; Gorse, C.; Longo, S.; Pagano, D.; Gicquel, A.; Hassouni, K.

    2005-04-06

    Different approaches to study vibrational kinetics coupled to electron one for modeling different kinds of negative ion sources are presented. In particular two types of sources are investigated. The first one is a classical negative ion source in which the plasma is generated by thermoemitted electrons; in the second one, electrons already present in the mixture are accelerated by an RF field to sufficiently high energy to ionize the gas molecules. For the first kind of ion source a new computational scheme is presented to couple heavy particle and electron kinetics. Moreover models developed for an RF inductive discharge and for a parallel plate discharge are described.

  15. Plasma acceleration using a radio frequency self-bias effect

    SciTech Connect (OSTI)

    Rafalskyi, D.; Aanesland, A.

    2015-06-15

    In this work plasma acceleration using a RF self-bias effect is experimentally studied. The experiments are conducted using a novel plasma accelerator system, called Neptune, consisting of an inductively coupled plasma source and a RF-biased set of grids. The plasma accelerator can operate in a steady state mode, producing a plasma flow with separately controlled plasma flux and velocity without any magnetic configuration. The operating pressure at the source output is as low as 0.2?mTorr and can further be decreased. The ion and electron flows are investigated by measuring the ion and electron energy distribution functions both space resolved and with different orientations with respect to the flow direction. It is found that the flow of electrons from the source is highly anisotropic and directed along the ion flow and this global flow of accelerated plasma is well localized in the plasma transport chamber. The maximum flux is about 7.5·10{sup 15} ions s{sup ?1} m{sup ?2} (at standard conditions) on the axis and decreasing to almost zero at a radial distances of more than 15?cm from the flow axis. Varying the RF acceleration voltage in the range 20–350?V, the plasma flow velocity can be changed between 10 and 35?km/s. The system is prospective for different technology such as space propulsion and surface modification and also interesting for fundamental studies for space-related plasma simulations and investigation of the dynamo effect using accelerated rotating plasmas.

  16. Characterization of an RF plasma ion source for ion implantation

    SciTech Connect (OSTI)

    Kopalidis, Peter M.; Wan Zhimin

    2012-11-06

    A novel inductively coupled RF plasma ion source has been developed for use in a beamline ion implanter. Ion density data have been taken with an array of four Langmuir probes spaced equally at the source extraction arc slit. These provide ion density uniformity information as a function of source pressure, RF power and gas mixture composition. In addition, total extracted ion beam current data are presented for the same conditions. The comparative advantages of the RF source in terms of higher beam current, reduced maintenance and overall productivity improvement compared to a hot cathode source are discussed.

  17. Absolute CF{sub 2} density and gas temperature measurements by absorption spectroscopy in dual-frequency capacitively coupled CF{sub 4}/Ar plasmas

    SciTech Connect (OSTI)

    Liu, Wen-Yao; Xu, Yong, E-mail: yongxu@dlut.edu.cn; Peng, Fei; Gong, Fa-Ping; Li, Xiao-Song; Zhu, Ai-Min [Key Laboratory of Materials Modification by Laser, Ion, and Electron Beams (Ministry of Education), School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Laboratory of Plasma Physical Chemistry, Dalian University of Technology, Dalian 116024 (China); Liu, Yong-Xin; Wang, You-Nian [Key Laboratory of Materials Modification by Laser, Ion, and Electron Beams (Ministry of Education), School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)

    2014-10-15

    Broadband ultraviolet absorption spectroscopy has been used to determine the CF{sub 2} radical density in dual-frequency capacitively coupled CF{sub 4}/Ar plasmas, using the CF{sub 2} A{sup ~1}B{sub 1}?X{sup ~1}A{sub 1} system of absorption spectrum. The rotational temperature of ground state CF{sub 2} and excited state CF was also estimated by using A{sup ~1}B{sub 1}?X{sup ~1}A{sub 1} system and B{sup 2}??X{sup 2}? system, respectively. The translational gas temperature was deduced from the Doppler width of the Ar{sup *}({sup 3}P{sub 2}) and Ar{sup *}({sup 3}P{sub 0}) metastable atoms absorption line by using the tunable diode laser absorption spectroscopy. The rotational temperatures of the excited state CF are about 100?K higher than those of ground state CF{sub 2}, and about 200?K higher than the translational gas temperatures. The dependences of the radical CF{sub 2} density, electron density, electron temperature, rotational temperature, and gas temperature on the high frequency power and pressure have been analyzed. Furthermore, the production and loss mechanisms of CF{sub 2} radical and the gas heating mechanisms have also been discussed.

  18. A Compact Disk Type Plasma Propulsion System with Modulated Magnetic Field for Nanoscale Space Vehicles

    SciTech Connect (OSTI)

    Fukuda, Takeshi; Ueda, Satoshi; Ohnishi, Yukihiro; Inomoto, Michiaki [Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, 565-0871 Osaka (Japan)

    2008-12-31

    A compact 5 mm disk type plasma thruster simply composed of only a set of antenna windings and bias field coil which produces significant thrust of 0.74 mN with rotating magnetic field has been proposed and successfully developed for future applications to low altitude nanosatellites. The key technology issue is that the rotating speed is set above the ion plasma frequency but far below the electron plasma frequency, in order to produce the electron drag current and axial electric field as a consequence of the interaction with the bias field. The formation of axial electric field was confirmed and the produced plasma density was >6x10{sup 18} m{sup -3}, whereas the power consumption is 500 W in the inductively coupled mode of operation. The anticipated thrust density and specific thrust could potentially be extended to 7.64 Nm{sup -2} and 850 s, respectively, which is comparable to conventional Hall effect thrusters.

  19. Hume, Induction, Probability

    E-Print Network [OSTI]

    Fitelson, Branden

    Hume, Induction, and Probability Peter J.R. Millican The University of Leeds Department is to understand Hume's famous argument concerning induction, and to appraise its success in establishing its for the argument (§4.3); (g) Refutation of Stove's well-known alternative diagram (§5.1); (h) Likewise of Stove

  20. Master Thesis: Fusion Plasma Thermal Transport

    E-Print Network [OSTI]

    Master Thesis: Fusion Plasma Thermal Transport Radial and Poloidal Profile Modeling Martin Olesen-axis localised ion cyclotron resonance heating source. 2. Cold pulse shock induction at the plasma edge via laser wave propagation from heat modulation and the fast propagation of a cold pulse, at the same plasma

  1. Hybrid-secondary uncluttered induction machine

    DOE Patents [OSTI]

    Hsu, John S. (Oak Ridge, TN)

    2001-01-01

    An uncluttered secondary induction machine (100) includes an uncluttered rotating transformer (66) which is mounted on the same shaft as the rotor (73) of the induction machine. Current in the rotor (73) is electrically connected to current in the rotor winding (67) of the transformer, which is not electrically connected to, but is magnetically coupled to, a stator secondary winding (40). The stator secondary winding (40) is alternately connected to an effective resistance (41), an AC source inverter (42) or a magnetic switch (43) to provide a cost effective slip-energy-controlled, adjustable speed, induction motor that operates over a wide speed range from below synchronous speed to above synchronous speed based on the AC line frequency fed to the stator.

  2. Progress on a New RF Plasma Generator a

    E-Print Network [OSTI]

    Target Plasma Boundary ITER Plasma Core 1m Upstream Downstream Hot Plasma Channel 10 MW/m2 max on target-recycling, strongly coupled PMI regime Upstream Downstream Hot Plasma Channel Magnetic Field Linear plasma channelW) & downstream plasma flow · Inferred from best match: ­ D2 depleted by ~104 at plasma center ­ Strong fueling

  3. Induction melter apparatus

    DOE Patents [OSTI]

    Roach, Jay A [Idaho Falls, ID; Richardson, John G [Idaho Falls, ID; Raivo, Brian D [Idaho Falls, ID; Soelberg, Nicholas R [Idaho Falls, ID

    2008-06-17

    Apparatus and methods of operation are provided for a cold-crucible-induction melter for vitrifying waste wherein a single induction power supply may be used to effect a selected thermal distribution by independently energizing at least two inductors. Also, a bottom drain assembly may be heated by an inductor and may include an electrically resistive heater. The bottom drain assembly may be cooled to solidify molten material passing therethrough to prevent discharge of molten material therefrom. Configurations are provided wherein the induction flux skin depth substantially corresponds with the central longitudinal axis of the crucible. Further, the drain tube may be positioned within the induction flux skin depth in relation to material within the crucible or may be substantially aligned with a direction of flow of molten material within the crucible. An improved head design including four shells forming thermal radiation shields and at least two gas-cooled plenums is also disclosed.

  4. Linear induction accelerator

    DOE Patents [OSTI]

    Buttram, M.T.; Ginn, J.W.

    1988-06-21

    A linear induction accelerator includes a plurality of adder cavities arranged in a series and provided in a structure which is evacuated so that a vacuum inductance is provided between each adder cavity and the structure. An energy storage system for the adder cavities includes a pulsed current source and a respective plurality of bipolar converting networks connected thereto. The bipolar high-voltage, high-repetition-rate square pulse train sets and resets the cavities. 4 figs.

  5. Control of power to an inductively heated part

    DOE Patents [OSTI]

    Adkins, D.R.; Frost, C.A.; Kahle, P.M.; Kelley, J.B.; Stanton, S.L.

    1997-05-20

    A process for induction hardening a part to a desired depth with an AC signal applied to the part from a closely coupled induction coil includes measuring the voltage of the AC signal at the coil and the current passing through the coil; and controlling the depth of hardening of the part from the measured voltage and current. The control system determines parameters of the part that are functions of applied voltage and current to the induction coil, and uses a neural network to control the application of the AC signal based on the detected functions for each part. 6 figs.

  6. Control of power to an inductively heated part

    DOE Patents [OSTI]

    Adkins, Douglas R. (1620 Adelita Dr. NE., Albuquerque, NM 87112); Frost, Charles A. (1039 Red Oaks Loop NE., Albuquerque, NM 87122); Kahle, Philip M. (528 Longwood Loop NE., Rio Rancho, NM 87124); Kelley, J. Bruce (13200 Blue Corn Maiden Trail NE., Albuquerque, NM 87112); Stanton, Suzanne L. (2805 Palo Alto NE., Albuquerque, NM 87112)

    1997-01-01

    A process for induction hardening a part to a desired depth with an AC signal applied to the part from a closely coupled induction coil includes measuring the voltage of the AC signal at the coil and the current passing through the coil; and controlling the depth of hardening of the part from the measured voltage and current. The control system determines parameters of the part that are functions of applied voltage and current to the induction coil, and uses a neural network to control the application of the AC signal based on the detected functions for each part.

  7. RF-Plasma Source Commissioning in Indian Negative Ion Facility

    SciTech Connect (OSTI)

    Singh, M. J.; Bandyopadhyay, M.; Yadava, Ratnakar; Chakraborty, A. K. [ITER- India, Institute for Plasma Research, A-29, Sector 25, GIDC, Gandhinagar, Gujrat (India); Bansal, G.; Gahlaut, A.; Soni, J.; Kumar, Sunil; Pandya, K.; Parmar, K. G.; Sonara, J. [Institute for Plasma Research, Bhat Gandhinagar, Gujrat (India); Kraus, W.; Heinemann, B.; Riedl, R.; Obermayer, S.; Martens, C.; Franzen, P.; Fantz, U. [Max-Planck-Institut fuer Plasmaphysik, Boltzmannstrasse 2, D-85748 Garching (Germany)

    2011-09-26

    The Indian program of the RF based negative ion source has started off with the commissioning of ROBIN, the inductively coupled RF based negative ion source facility under establishment at Institute for Plasma research (IPR), India. The facility is being developed under a technology transfer agreement with IPP Garching. It consists of a single RF driver based beam source (BATMAN replica) coupled to a 100 kW, 1 MHz RF generator with a self excited oscillator, through a matching network, for plasma production and ion extraction and acceleration. The delivery of the RF generator and the RF plasma source without the accelerator, has enabled initiation of plasma production experiments. The recent experimental campaign has established the matching circuit parameters that result in plasma production with density in the range of 0.5-1x10{sup 18}/m{sup 3}, at operational gas pressures ranging between 0.4-1 Pa. Various configurations of the matching network have been experimented upon to obtain a stable operation of the set up for RF powers ranging between 25-85 kW and pulse lengths ranging between 4-20 s. It has been observed that the range of the parameters of the matching circuit, over which the frequency of the power supply is stable, is narrow and further experiments with increased number of turns in the coil are in the pipeline to see if the range can be widened. In this paper, the description of the experimental system and the commissioning data related to the optimisation of the various parameters of the matching network, to obtain stable plasma of required density, are presented and discussed.

  8. On Automating Inductive and Non-Inductive Termination Methods

    E-Print Network [OSTI]

    Kamareddine, Fairouz

    On Automating Inductive and Non-Inductive Termination Methods Fairouz Kamareddine and Francois of the function which satis es a notion of terminal prop- erty and then verifying that this construction processPre can only deal with the termination proofs that are inductive. There are however many functions

  9. Low inductance connector assembly

    DOE Patents [OSTI]

    Holbrook, Meghan Ann; Carlson, Douglas S

    2013-07-09

    A busbar connector assembly for coupling first and second terminals on a two-terminal device to first and second contacts on a power module is provided. The first terminal resides proximate the first contact and the second terminal resides proximate the second contact. The assembly comprises a first bridge having a first end configured to be electrically coupled to the first terminal, and a second end configured to be electrically coupled to the second contact, and a second bridge substantially overlapping the first bridge and having a first end electrically coupled to the first contact, and a second end electrically coupled to the second terminal.

  10. Effects of H{sub 2} plasma treatment on the electrical properties of titanium-doped indium oxide films prepared by polymer-assisted deposition

    SciTech Connect (OSTI)

    Hwang, Joo-Sang; Lee, Ji-Myon; Vishwanath, Sujaya Kumar; Kim, Jihoon

    2015-07-15

    The effects of hydrogen (H{sub 2}) plasma on the optical and electrical properties of titanium-doped InO (TIO) grown on glass substrates using polymer-assisted deposition are reported. Samples were exposed to H{sub 2} plasma formed by inductively coupled plasma (ICP). After plasma treatment at a power of 100?W, the sheet resistance of the TIO films decreased from 11?000 to 285??/sq. Additionally, the Hall mobility and sheet carrier concentration of the films increased as the ICP source power was increased to 100?W, without affecting the optical transmittance of the films, due to the removal of the polymer residues and the formation of oxygen vacancies.

  11. Low inductance busbar assembly

    DOE Patents [OSTI]

    Holbrook, Meghan Ann (Manhattan Beach, CA)

    2010-09-21

    A busbar assembly for electrically coupling first and second busbars to first and second contacts, respectively, on a power module is provided. The assembly comprises a first terminal integrally formed with the first busbar, a second terminal integrally formed with the second busbar and overlapping the first terminal, a first bridge electrode having a first tab electrically coupled to the first terminal and overlapping the first and second terminals, and a second tab electrically coupled to the first contact, a second bridge electrode having a third tab electrically coupled to the second terminal, and overlapping the first and second terminals and the first tab, and a fourth tab electrically coupled to the second contact, and a fastener configured to couple the first tab to the first terminal, and the third tab to the second terminal.

  12. Feedback regulated induction heater for a flowing fluid

    DOE Patents [OSTI]

    Migliori, Albert (Santa Fe, NM); Swift, Gregory W. (Los Alamos, NM)

    1985-01-01

    A regulated induction heater for heating a stream of flowing fluid to a predetermined desired temperature. The heater includes a radiofrequency induction coil which surrounds a glass tube through which the fluid flows. A heating element consisting of a bundle of approximately 200 stainless steel capillary tubes located within the glass tube couples the output of the induction coil to the fluid. The temperature of the fluid downstream from the heating element is sensed with a platinum resistance thermometer, the output of which is applied to an adjustable proportional and integral feedback control circuit which regulates the power applied to the induction coil. The heater regulates the fluid temperature to within 0.005.degree. C. at a flow rate of 50 cm.sup.3 /second with a response time of less than 0.1 second, and can accommodate changes in heat load up to 1500 watts.

  13. Feedback regulated induction heater for a flowing fluid

    DOE Patents [OSTI]

    Migliori, A.; Swift, G.W.

    1984-06-13

    A regulated induction heater for heating a stream of flowing fluid to a predetermined desired temperature. The heater includes a radiofrequency induction coil which surrounds a glass tube through which the fluid flows. A heating element consisting of a bundle of approximately 200 stainless steel capillary tubes located within the glass tube couples the output of the induction coil to the fluid. The temperature of the fluid downstream from the heating element is sensed with a platinum resistance thermometer, the output of which is applied to an adjustable porportional and integral feedback control circuit which regulates the power applied to the induction coil. The heater regulates the fluid temperature to within 0.005/sup 0/C at a flow rate of 50 cm/sup 3//sec with a response time of less than 0.1 second, and can accommodate changes in heat load up to 1500 watts.

  14. Properties of On-Chip Inductive Current Loops Andrey V. Mezhiba and Eby G. Friedman

    E-Print Network [OSTI]

    Friedman, Eby G.

    dimensions. This linear behavior can be used to simplify the inductance extraction and circuit analysis the interconnects are tightly coupled, the current return path is typically not known prior to the circuit analysis@ece.rochester.edu, friedman@ece.rochester.edu Abstract The variation of inductance with circuit length is investigated

  15. NSTX Weekly Report (September 10, 2010) FY 2010 NSTX plasma operations

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    . On Sept 7 and 8, we began the Coaxial Helicity Injection (CHI) experiment, XP 1034 "Flux saving to Ohmic plasmas reaching 1MA of current with significant flux savings over purely inductive plasmas

  16. Harmonic control of multiple-stator induction machines for voltage regulation

    E-Print Network [OSTI]

    Holloway, Jack Wade, 1980-

    2004-01-01

    Small, one to a few horsepower, three-phase induction machines with three sets of electrically-isolated, magnetically-coupled stator winding circuits are described. A voltage inverter is developed and used to drive one set ...

  17. Superconducting inductive displacement detection of a microcantilever

    SciTech Connect (OSTI)

    Vinante, A., E-mail: anvinante@fbk.eu [Istituto di Fotonica e Nanotecnologie, CNR - Fondazione Bruno Kessler, I-38123 Povo, Trento (Italy)

    2014-07-21

    We demonstrate a superconducting inductive technique to measure the displacement of a micromechanical resonator. In our scheme, a type I superconducting microsphere is attached to the free end of a microcantilever and approached to the loop of a dc Superconducting Quantum Interference Device (SQUID) microsusceptometer. A local magnetic field as low as 100??T, generated by a field coil concentric to the SQUID, enables detection of the cantilever thermomechanical noise at 4.2?K. The magnetomechanical coupling and the magnetic spring are in good agreement with image method calculations assuming pure Meissner effect. These measurements are relevant to recent proposals of quantum magnetomechanics experiments based on levitating superconducting microparticles.

  18. Resonant-cavity antenna for plasma heating

    DOE Patents [OSTI]

    Perkins, Jr., Francis W. (Princeton, NJ); Chiu, Shiu-Chu (San Diego, CA); Parks, Paul (San Diego, CA); Rawls, John M. (Del Mar, CA)

    1987-01-01

    Disclosed is a resonant coil cavity wave launcher for energizing a plasma immersed in a magnetic field. Energization includes launching fast Alfven waves to excite ion cyclotron frequency resonances in the plasma. The cavity includes inductive and capacitive reactive members spaced no further than one-quarter wavelength from a first wall confinement chamber of the plasma. The cavity wave launcher is energized by connection to a waveguide or transmission line carrying forward power from a remote radio frequency energy source.

  19. Experimental investigations of electron density and ion energy distributions in dual-frequency capacitively coupled plasmas for Ar/CF{sub 4} and Ar/O{sub 2}/CF{sub 4} discharges

    SciTech Connect (OSTI)

    Liu, Jia; Liu, Yong-Xin; Gao, Fei; Wang, You-Nian, E-mail: ynwang@dlut.edu.cn [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Bi, Zhen-Hua [School of Physics and Materials Engineering, Dalian Nationalities University, Dalian 116600 (China)

    2014-01-07

    The electron density and ion energy distribution (IED) are investigated in low-pressure dual-frequency capacitively coupled Ar/CF{sub 4} (90%/10%) and Ar/O{sub 2}/CF{sub 4} (80%/10%/10%) plasmas. The relations between controllable parameters, such as high-frequency (HF) power, low-frequency (LF) power and gas pressure, and plasma parameters, such as electron density and IEDs, are studied in detail by utilizing a floating hairpin probe and an energy resolved quadrupole mass spectrometer, respectively. In our experiment, the electron density is mainly determined by the HF power and slightly influenced by the LF power. With increasing gas pressure, the electron density first goes up rapidly to a maximum value and then decreases at various HF and LF powers. The HF power also plays a considerable role in affecting the IEDs under certain conditions and the ion energy independently controlled by the LF source is discussed here. For clarity, some numerical results obtained from a two-dimensional fluid model are presented.

  20. Effect of H2 on the etch profile of InPInGaAsP alloys in Cl2 ArH2 inductively coupled plasma reactive ion etching chemistries

    E-Print Network [OSTI]

    Rommel, Sean

    extensively. Dry-etching studies of InP have pursued two general chemistries: methane-based etching and Cl2-based etching. Reactive ion etching studies typically pursued a CH4 /H2 etch in conjunction Cl2 /Ar in a chemically assisted ion-beam etching chamber was established by Youtsey et al.7

  1. Engineering of porosity in amorphous materials. Plasma oxidation of hydrocarbon templates in polysilsesquioxanes

    SciTech Connect (OSTI)

    Loy, D.A.; Buss, R.J.; Assink, R.A. [Sandia National Labs., Albuquerque, NM (United States); Shea, K.J.; Oviatt, H. [Univ. of California, Irvine, CA (United States)

    1994-12-31

    Arylene- and alkylene-bridged polysilsesquioxanes were prepared by sol-gel processing of bis(triethoxysilyl)-arylene monomers 1--4, and alkylene monomers 5--9. The arylene polysilsesquioxanes were porous materials with surface areas as high as 830 m{sup 2}/g (BET). Treatment with an inductively coupled oxygen plasma resulted in the near quantitative removal of the arylene bridging groups and a coarsening of the pore structure. Solid state {sup 29}Si NMR was used to confirm the conversion of the sesquioxane silicons (T) to silica (Q). The alkylene-bridged polysilsesquioxanes were non-porous. Oxygen plasma treatment afforded silica gels with mesoporosity. The porosity in the silica gels appears to arise entirely from the oxidation of the alkylene spacers.

  2. Porous materials by design. Plasma oxidation of hydrocarbon templates in polysilsesquioxanes

    SciTech Connect (OSTI)

    Loy, D.A.; Buss, R.J.; Assink, R.A. [Sandia National Labs., Albuquerque, NM (United States); Shea, K.J.; Oviatt, H. [California Univ., Irvine, CA (United States). Dept. of Chemistry

    1992-12-31

    Arylene- and alkylene-bridged polysilsesquioxanes were prepared by sol-gel processing of bis(triethoxysilyl)-aryl monomers and decyl monomer. The arylene polysilsesquioxanes were porous materials with surface areas as high as 830 m{sup 2}/g (BET). Treatment with an inductively coupled oxygen plasma resulted in the near quantitative removal of the arylene bridging groups and a coarsening of the pore structure. Solid state {sup 29}Si NMR was used to confirm the conversion of the sesquioxane silicons (T) to silica (Q). The decylene-bridged polysilsesquioxane was a non-porous material. Oxygen plasma treatment afforded a silica gel with a surface area of 294 m{sup 2}/g and a mean pore diameter of 46 {Angstrom}. The porosity in the silica gel appears to arise entirely from the oxidation of the 1,10-decylene spacer.

  3. Porous materials by design. Plasma oxidation of hydrocarbon templates in polysilsesquioxanes

    SciTech Connect (OSTI)

    Loy, D.A.; Buss, R.J.; Assink, R.A. [Sandia National Laboratories, Albuquerque, NM (United States); Shea, K.J.; Oviatt, H. [Univ. of California, Irvine, CA (United States)

    1993-12-31

    Arylene- and alkylene-bridged polysilsesquioxanes were prepared by sol-gel processing of bis (triethoxysilyl)-aryl monomers 1-4 and decyl monomer 5. The arylene polysilsesquioxanes were porous materials with surface areas as high as 830 m{sup 2}/g (BET). Treatment with an inductively coupled oxygen plasma resulted in the near quantitative removal of the arylene bridging groups and a coarsening of the pore structure. Solid state {sup 29}Si NMR was used to confirm the conversion of the sesquioxane silicons (T) to silica (Q). The decylene-bridged polysilsesquinoxane was non-porous materials. Oxygen plasma treatment afforded a silica gel with a surface area of 294 m{sup 2}/g and a mean pore diameter of 46 {angstrom}. The porosity in the silica gel appears to arise entirely from the oxidation of the 1,10-decylene spacer.

  4. Advanced plasma flow simulations of cathodic-arc and ferroelectric plasma sources for neutralized drift compression experiments

    E-Print Network [OSTI]

    Gilson, Erik

    Advanced plasma flow simulations of cathodic-arc and ferroelectric plasma sources for neutralized cathodic-arc plasma source show the coupling efficiency of the plasma flow from the source to the drift drift compression experiments Adam B. Sefkow, Ronald C. Davidson, and Erik P. Gilson Plasma Physics

  5. Entangling flux qubits with a bipolar dynamic inductance

    E-Print Network [OSTI]

    B. L. T. Plourde; J. Zhang; K. B. Whaley; F. K. Wilhelm; T. L. Robertson; T. Hime; S. Linzen; P. A. Reichardt; C. -E. Wu; John Clarke

    2004-06-08

    We propose a scheme to implement variable coupling between two flux qubits using the screening current response of a dc Superconducting QUantum Interference Device (SQUID). The coupling strength is adjusted by the current bias applied to the SQUID and can be varied continuously from positive to negative values, allowing cancellation of the direct mutual inductance between the qubits. We show that this variable coupling scheme permits efficient realization of universal quantum logic. The same SQUID can be used to determine the flux states of the qubits.

  6. Implantation, flux and recoil distributions for plasma species impinging on tokamak divertor materials

    E-Print Network [OSTI]

    Moshman, Nathan David

    2009-01-01

    Plasma Species Impinging on Tokamak Divertor Materials. APlasma Species Impinging on Tokamak Divertor Materials. byquantities needed to couple tokamak edge plasma to coolant

  7. Accounting & Finance (BAcc) Induction 2014

    E-Print Network [OSTI]

    Glasgow, University of

    Accounting & Finance (BAcc) Induction 2014 Monday 15 September 2014 Induction Programme: 0945] Welcome from the Business School and Accounting & Finance 1000 The Accountancy Degrees 1015 Programme & 3 on Level 4 Accounting & Finance Bldg Tuesday 16 September 2014 Advising Session Lunch (provided

  8. HEALTH AND SAFETY INDUCTION Introduction

    E-Print Network [OSTI]

    Mucina, Ladislav

    HEALTH AND SAFETY INDUCTION Introduction Welcome to Curtin's online health and safety induction University is committed to providing and maintaining high standards of health and safety so we can prevent with staff, and by continually improving our health and safety management system. This course is designed

  9. Inductance due to spin current

    SciTech Connect (OSTI)

    Chen, Wei

    2014-03-21

    The inductance of spintronic devices that transport charge neutral spin currents is discussed. It is known that in a media that contains charge neutral spins, a time-varying electric field induces a spin current. We show that since the spin current itself produces an electric field, this implies existence of inductance and electromotive force when the spin current changes with time. The relations between the electromotive force and the corresponding flux, which is a vector calculated by the cross product of electric field and the trajectory of the device, are clarified. The relativistic origin generally renders an extremely small inductance, which indicates the advantage of spin current in building low inductance devices. The same argument also explains the inductance due to electric dipole current and applies to physical dipoles consist of polarized bound charges.

  10. Sensor Driven Intelligent Control System For Plasma Processing

    SciTech Connect (OSTI)

    Bell, G.; Campbell, V.B.

    1998-02-23

    This Cooperative Research and Development Agreement (CRADA) between Innovative Computing Technologies, Inc. (IC Tech) and Martin Marietta Energy Systems (MMES) was undertaken to contribute to improved process control for microelectronic device fabrication. Process data from an amorphous silicon thin film deposition experiment was acquired to validate the performance of an intelligent, adaptive, neurally-inspired control software module designed to provide closed loop control of plasma processing machines used in the microelectronics industry. Data acquisition software was written using LabView The data was collected from an inductively coupled plasma (ICP) source, which was available for this project through LMES's RF/Microwave Technology Center. Experimental parameters measured were RF power, RF current and voltage on the antenna delivering power to the plasma, hydrogen and silane flow rate, chamber pressure, substrate temperature and H-alpha optical emission. Experimental results obtained were poly-crystallin silicon deposition rate, crystallinity, crystallographic orientation and electrical conductivity. Owing to experimental delays resulting from hardware failures, it was not possible to assemble a complete data for IC Tech use within the time and resource constraints of the CRADA. IC Tech was therefore not able to verify the performance of their existing models and control structures and validate model performance under this CRADA.

  11. Plasma Physics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    4 Plasma Physics By leveraging plasma under extreme conditions, we concentrate on solving critical scientific challenges such as detecting smuggled nuclear materials, advancing...

  12. Magnetic field distribution in the plasma flow generated by a plasma focus discharge

    SciTech Connect (OSTI)

    Mitrofanov, K. N.; Krauz, V. I. Myalton, V. V.; Velikhov, E. P.; Vinogradov, V. P.; Vinogradova, Yu. V.

    2014-11-15

    The magnetic field in the plasma jet propagating from the plasma pinch region along the axis of the chamber in a megajoule PF-3 plasma focus facility is studied. The dynamics of plasma with a trapped magnetic flow is analyzed. The spatial sizes of the plasma jet region in which the magnetic field concentrates are determined in the radial and axial directions. The magnetic field configuration in the plasma jet is investigated: the radial distribution of the azimuthal component of the magnetic field inside the jet is determined. It is shown that the magnetic induction vector at a given point in space can change its direction during the plasma flight. Conclusions regarding the symmetry of the plasma flow propagation relative to the chamber axis are drawn.

  13. Induction loop detector systems crosstalk 

    E-Print Network [OSTI]

    Bhagat, Victor

    1994-01-01

    traffic control systems are necessary to obtain maximum possible efficiency from our freeway systems. A major component of freeway management systems is the induction loop detector. This research effort evaluated the methods by which crosstalk could...

  14. Operating an induction melter apparatus

    DOE Patents [OSTI]

    Roach, Jay A.; Richardson, John G.; Raivo, Brian D.; Soelberg, Nicholas R.

    2006-01-31

    Apparatus and methods of operation are provided for a cold-crucible-induction melter for vitrifying waste wherein a single induction power supply may be used to effect a selected thermal distribution by independently energizing at least two inductors. Also, a bottom drain assembly may be heated by an inductor and may include an electrically resistive heater. The bottom drain assembly may be cooled to solidify molten material passing therethrough to prevent discharge of molten material therefrom. Configurations are provided wherein the induction flux skin depth substantially corresponds with the central longitudinal axis of the crucible. Further, the drain tube may be positioned within the induction flux skin depth in relation to material within the crucible or may be substantially aligned with a direction of flow of molten material within the crucible. An improved head design including four shells forming thermal radiation shields and at least two gas-cooled plenums is also disclosed.

  15. Parallel algorithms for inductance extraction 

    E-Print Network [OSTI]

    Mahawar, Hemant

    2007-09-17

    In VLSI circuits, signal delays play an important role in design, timing verification and signal integrity checks. These delays are attributed to the presence of parasitic resistance, capacitance and inductance. With ...

  16. Modeling Stem Cell Induction Processes

    E-Print Network [OSTI]

    Gracio, Filipe

    Technology for converting human cells to pluripotent stem cell using induction processes has the potential to revolutionize regenerative medicine. However, the production of these so called iPS cells is still quite inefficient ...

  17. Particle formation and its control in dual frequency plasma etching reactors

    SciTech Connect (OSTI)

    Kim, Munsu; Cheong, Hee-Woon; Whang, Ki-Woong

    2015-07-15

    The behavior of a particle cloud in plasma etching reactors at the moment when radio frequency (RF) power changes, that is, turning off and transition steps, was observed using the laser-light-scattering method. Two types of reactors, dual-frequency capacitively coupled plasma (CCP) and the hybrid CCP/inductively coupled plasma (ICP), were set up for experiments. In the hybrid CCP/ICP reactor (hereafter ICP reactor), the position and shape of the cloud were strongly dependent on the RF frequency. The particle cloud becomes larger and approaches the electrode as the RF frequency increases. By turning the lower frequency power off later with a small delay time, the particle cloud is made to move away from the electrode. Maintaining lower frequency RF power only was also helpful to reduce the particle cloud size during this transition step. In the ICP reactor, a sufficient bias power is necessary to make a particle trap appear. A similar particle cloud to that in the CCP reactor was observed around the sheath region of the lower electrode. The authors can also use the low-frequency effect to move the particle cloud away from the substrate holder if two or more bias powers are applied to the substrate holder. The dependence of the particle behavior on the RF frequencies suggests that choosing the proper frequency at the right moment during RF power changes can reduce particle contamination effectively.

  18. Real-time, noninvasive monitoring of ion energy and ion current at a wafer surface during plasma etching

    SciTech Connect (OSTI)

    Sobolewski, Mark A. [National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States)

    2006-09-15

    A noninvasive, nonperturbing technique for real-time monitoring of ion energy distributions and total ion current at a wafer surface during plasma processing has been used to monitor rapid changes in CF{sub 4}/Ar etching plasmas in an inductively coupled, rf-biased plasma reactor. To mimic the effects of process recipe steps or reactor malfunctions, perturbations were made in the inductive source power, gas flow, and pressure, and the resulting effects on total ion current, sheath voltage, and ion energy were monitored. During etching of a thermal silicon dioxide film, smaller changes, which are caused by the etch process itself, were also observed. Sheath voltages determined by the noninvasive technique were in good agreement with simultaneous measurements made using a capacitive probe. In addition to providing a demonstration of the speed and accuracy of the technique, the results also provide useful information about the relative importance of different types of equipment malfunctions and suggest methods for minimizing their effects. In particular, operating at constant bias voltage, instead of constant bias power, gave more stable ion energies. The physical mechanisms that cause the observed changes in ion energy are discussed, and a comparison to other process monitoring methods is presented. No other noninvasive, nonperturbing method yields ion current or ion energies as accurately as the technique presented here.

  19. Noise performance of magneto-inductive cables

    SciTech Connect (OSTI)

    Wiltshire, M. C. K. Syms, R. R. A.

    2014-07-21

    Magneto-inductive (MI) waveguides are metamaterial structures based on periodic arrangements of inductively coupled resonant magnetic elements. They are of interest for power transfer, communications and sensing, and can be realised in a flexible cable format. Signal-to-noise ratio is extremely important in applications involving signals. Here, we present the first experimental measurements of the noise performance of metamaterial cables. We focus on an application involving radiofrequency signal transmission in internal magnetic resonance imaging (MRI), where the subdivision of the metamaterial cable provides intrinsic patient safety. We consider MI cables suitable for use at 300 MHz during {sup 1}H MRI at 7 T, and find noise figures of 2.3–2.8?dB/m, together with losses of 3.0–3.9?dB/m, in good agreement with model calculations. These values are high compared to conventional cables, but become acceptable when (as here) the environment precludes the use of continuous conductors. To understand this behaviour, we present arguments for the fundamental performance limitations of these cables.

  20. Plasma generating apparatus for large area plasma processing

    DOE Patents [OSTI]

    Tsai, C.C.; Gorbatkin, S.M.; Berry, L.A.

    1991-07-16

    A plasma generating apparatus for plasma processing applications is based on a permanent magnet line-cusp plasma confinement chamber coupled to a compact single-coil microwave waveguide launcher. The device creates an electron cyclotron resonance (ECR) plasma in the launcher and a second ECR plasma is created in the line cusps due to a 0.0875 tesla magnetic field in that region. Additional special magnetic field configuring reduces the magnetic field at the substrate to below 0.001 tesla. The resulting plasma source is capable of producing large-area (20-cm diam), highly uniform (.+-.5%) ion beams with current densities above 5 mA/cm[sup 2]. The source has been used to etch photoresist on 5-inch diam silicon wafers with good uniformity. 3 figures.

  1. Plasma generating apparatus for large area plasma processing

    DOE Patents [OSTI]

    Tsai, Chin-Chi (Oak Ridge, TN); Gorbatkin, Steven M. (Oak Ridge, TN); Berry, Lee A. (Oak Ridge, TN)

    1991-01-01

    A plasma generating apparatus for plasma processing applications is based on a permanent magnet line-cusp plasma confinement chamber coupled to a compact single-coil microwave waveguide launcher. The device creates an electron cyclotron resonance (ECR) plasma in the launcher and a second ECR plasma is created in the line cusps due to a 0.0875 tesla magnetic field in that region. Additional special magnetic field configuring reduces the magnetic field at the substrate to below 0.001 tesla. The resulting plasma source is capable of producing large-area (20-cm diam), highly uniform (.+-.5%) ion beams with current densities above 5 mA/cm.sup.2. The source has been used to etch photoresist on 5-inch diam silicon wafers with good uniformity.

  2. Loop-to-loop coupling.

    SciTech Connect (OSTI)

    Warne, Larry Kevin; Lucero, Larry Martin; Langston, William L.; Salazar, Robert Austin; Coleman, Phillip Dale; Basilio, Lorena I.; Bacon, Larry Donald

    2012-05-01

    This report estimates inductively-coupled energy to a low-impedance load in a loop-to-loop arrangement. Both analytical models and full-wave numerical simulations are used and the resulting fields, coupled powers and energies are compared. The energies are simply estimated from the coupled powers through approximations to the energy theorem. The transmitter loop is taken to be either a circular geometry or a rectangular-loop (stripline-type) geometry that was used in an experimental setup. Simple magnetic field models are constructed and used to estimate the mutual inductance to the receiving loop, which is taken to be circular with one or several turns. Circuit elements are estimated and used to determine the coupled current and power (an equivalent antenna picture is also given). These results are compared to an electromagnetic simulation of the transmitter geometry. Simple approximate relations are also given to estimate coupled energy from the power. The effect of additional loads in the form of attached leads, forming transmission lines, are considered. The results are summarized in a set of susceptibility-type curves. Finally, we also consider drives to the cables themselves and the resulting common-to-differential mode currents in the load.

  3. F1-CN-64/AP2-17 DEUTERIUM-TRITIUM TFTR PLASMAS WITH HIGH

    E-Print Network [OSTI]

    Budny, Robert

    . The fusion power output, Pf, in high temperature tokamak plasmas heated by neutral beam injection scales by increasing the product of li Ip . Technical aspects of generating the high li plasma in previous experimentsF1-CN-64/AP2-17 DEUTERIUM-TRITIUM TFTR PLASMAS WITH HIGH INTERNAL INDUCTANCE* S. A. SABBAGH1 , E. D

  4. Radiofrequency plasma antenna generated by femtosecond laser filaments in air

    SciTech Connect (OSTI)

    Brelet, Y.; Houard, A.; Point, G.; Prade, B.; Carbonnel, J.; Andre, Y.-B.; Mysyrowicz, A. [Laboratoire d'Optique Appliquee, ENSTA ParisTech, Ecole Polytechnique, CNRS, 91761 Palaiseau (France); Arantchouk, L. [Laboratoire de Physique des Plasmas, Ecole Polytechnique, CNRS, Palaiseau (France); Pellet, M. [Etat-major de la Marine Nationale, Paris (France)

    2012-12-24

    We demonstrate tunable radiofrequency emission from a meter-long linear plasma column produced in air at atmospheric pressure. A short-lived plasma column is initially produced by femtosecond filamentation and subsequently converted into a long-lived discharge column by application of an external high voltage field. Radiofrequency excitation is fed to the plasma by induction and detected remotely as electromagnetic radiation by a classical antenna.

  5. The Automation Of Proof By Mathematical Induction 

    E-Print Network [OSTI]

    Bundy, Alan

    This paper is a chapter of the Handbook of Automated Reasoning edited by Voronkov and Robinson. It describes techniques for automated reasoning in theories containing rules of mathematical induction. Firstly, inductive reasoning is defined and its...

  6. Sensorless performance evaluation of induction motors 

    E-Print Network [OSTI]

    Ahmed, Shehab

    2000-01-01

    In this thesis, various aspects of induction motor performance are discussed. The importance of the speed-torque curve for an induction motor system and its various applications are emphasized. Difficulties in the presently available methods...

  7. Helix coupling

    DOE Patents [OSTI]

    Ginell, W.S.

    1982-03-17

    A coupling for connecting helix members in series, which consists of a pair of U-shaped elements, one of which is attached to each helix end with the U sections of the elements interlocked. The coupling is particularly beneficial for interconnecting helical Nitinol elements utilized in thermal actuators or engines. Each coupling half is attached to the associated helix at two points, thereby providing axial load while being easily removed from the helix, and reusable.

  8. Helix coupling

    DOE Patents [OSTI]

    Ginell, William S. (Encino, CA)

    1989-04-25

    A coupling for connecting helix members in series, which consists of a pair of U-shaped elements, one of which is attached to each helix end with the "U" sections of the elements interlocked. The coupling is particularly beneficial for interconnecting helical Nitinol elements utilized in thermal actuators or engines. Each coupling half is attached to the associated helix at two points, thereby providing axial load while being easily removed from the helix, and reusable.

  9. Advanced ST Plasma Scenario Simulations for NSTX

    SciTech Connect (OSTI)

    C.E. Kessel; E.J. Synakowski; D.A. Gates; R.W. Harvey; S.M. Kaye; T.K. Mau; J. Menard; C.K. Phillips; G. Taylor; R. Wilson; the NSTX Research Team

    2004-10-28

    Integrated scenario simulations are done for NSTX [National Spherical Torus Experiment] that address four primary milestones for developing advanced ST configurations: high {beta} and high {beta}{sub N} inductive discharges to study all aspects of ST physics in the high-beta regime; non-inductively sustained discharges for flattop times greater than the skin time to study the various current-drive techniques; non-inductively sustained discharges at high {beta} for flattop times much greater than a skin time which provides the integrated advanced ST target for NSTX; and non-solenoidal start-up and plasma current ramp-up. The simulations done here use the Tokamak Simulation Code (TSC) and are based on a discharge 109070. TRANSP analysis of the discharge provided the thermal diffusivities for electrons and ions, the neutral-beam (NB) deposition profile, and other characteristics. CURRAY is used to calculate the High Harmonic Fast Wave (HHFW) heating depositions and current drive. GENRAY/CQL3D is used to establish the heating and CD [current drive] deposition profiles for electron Bernstein waves (EBW). Analysis of the ideal-MHD stability is done with JSOLVER, BALMSC, and PEST2. The simulations indicate that the integrated advanced ST plasma is reachable, obtaining stable plasmas with {beta} {approx} 40% at {beta}{sub N}'s of 7.7-9, I{sub P} = 1.0 MA, and B{sub T} = 0.35 T. The plasma is 100% non-inductive and has a flattop of 4 skin times. The resulting global energy confinement corresponds to a multiplier of H{sub 98(y,2)} = 1.5. The simulations have demonstrated the importance of HHFW heating and CD, EBW off-axis CD, strong plasma shaping, density control, and early heating/H-mode transition for producing and optimizing these plasma configurations.

  10. INDUCTION MOTOR FAULT DIAGNOSTIC AND MONITORING METHODS

    E-Print Network [OSTI]

    Povinelli, Richard J.

    INDUCTION MOTOR FAULT DIAGNOSTIC AND MONITORING METHODS by Aderiano M. da Silva, B.S. A Thesis;i Abstract Induction motors are used worldwide as the "workhorse" in industrial applications material. However, induction motor faults can be detected in an initial stage in order to prevent

  11. Stability of coupled tearing and twisting modes in tokamaks Richard Fitzpatrick

    E-Print Network [OSTI]

    Fitzpatrick, Richard

    Stability of coupled tearing and twisting modes in tokamaks Richard Fitzpatrick Citation: Physics tearing and twisting modes in tokamaks''' [Phys. Plasmas 1, 3308 (1994)] Phys. Plasmas 2, 3925 (1995); 10.1063/1.871024 Comment on ``Stability of coupled tearing and twisting modes in tokamaks'' [Phys. Plasmas 1, 3308 (1994

  12. Comparison of surface vacuum ultraviolet emissions with resonance level number densities. I. Argon plasmas

    SciTech Connect (OSTI)

    Boffard, John B., E-mail: jboffard@wisc.edu; Lin, Chun C. [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States); Culver, Cody [Materials Science Program, University of Wisconsin, Madison, WI 53706 (United States); Wang, Shicong; Wendt, Amy E. [Department of Electrical and Computer Engineering, University of Wisconsin, Madison, WI 53706 (United States); Radovanov, Svetlana; Persing, Harold [Varian Semiconductor Equipment, Applied Materials Inc., Gloucester, MA 01939 (United States)

    2014-03-15

    Vacuum ultraviolet (VUV) photons emitted from excited atomic states are ubiquitous in material processing plasmas. The highly energetic photons can induce surface damage by driving surface reactions, disordering surface regions, and affecting bonds in the bulk material. In argon plasmas, the VUV emissions are due to the decay of the 1s{sub 4} and 1s{sub 2} principal resonance levels with emission wavelengths of 104.8 and 106.7?nm, respectively. The authors have measured the number densities of atoms in the two resonance levels using both white light optical absorption spectroscopy and radiation-trapping induced changes in the 3p{sup 5}4p?3p{sup 5}4s branching fractions measured via visible/near-infrared optical emission spectroscopy in an argon inductively coupled plasma as a function of both pressure and power. An emission model that takes into account radiation trapping was used to calculate the VUV emission rate. The model results were compared to experimental measurements made with a National Institute of Standards and Technology-calibrated VUV photodiode. The photodiode and model results are in generally good accord and reveal a strong dependence on the neutral gas temperature.

  13. Plasma Physics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    state. Formed at high temperatures, plasmas consist of freely moving ions and free electrons. They are often called the "fourth state of matter" because their unique physical...

  14. Plasma gun notes Here are some notes based on an idea of Paul Bellan's (see his Spheromak

    E-Print Network [OSTI]

    Brown, Michael R.

    Plasma gun notes Here are some notes based on an idea of Paul Bellan's (see his Spheromak book H pj = qj The Hamilton approach is elegant and exposes conservation laws. 2. Plasma gun: We can model the plasma gun as coaxial inductor with inductance L(x) = L0 +Lx and a fixed capacitor on the back

  15. Elevated levels of plasma Big endothelin-1 and its relation to hypertension and skin lesions in individuals exposed to arsenic

    SciTech Connect (OSTI)

    Hossain, Ekhtear; Islam, Khairul; Yeasmin, Fouzia [Department of Biochemistry and Molecular Biology, Rajshahi University, Rajshahi-6205 (Bangladesh)] [Department of Biochemistry and Molecular Biology, Rajshahi University, Rajshahi-6205 (Bangladesh); Karim, Md. Rezaul [Department of Applied Nutrition and Food Technology, Islamic University, Kushtia-7003 (Bangladesh)] [Department of Applied Nutrition and Food Technology, Islamic University, Kushtia-7003 (Bangladesh); Rahman, Mashiur; Agarwal, Smita; Hossain, Shakhawoat; Aziz, Abdul; Al Mamun, Abdullah; Sheikh, Afzal; Haque, Abedul; Hossain, M. Tofazzal [Department of Biochemistry and Molecular Biology, Rajshahi University, Rajshahi-6205 (Bangladesh)] [Department of Biochemistry and Molecular Biology, Rajshahi University, Rajshahi-6205 (Bangladesh); Hossain, Mostaque [Department of Medicine, Bangladesh Institute of Research and Rehabilitation in Diabetes, Endocrine and Metabolic Disorders (BIRDEM), Dhaka (Bangladesh)] [Department of Medicine, Bangladesh Institute of Research and Rehabilitation in Diabetes, Endocrine and Metabolic Disorders (BIRDEM), Dhaka (Bangladesh); Haris, Parvez I. [Faculty of Health and Life Sciences, De Montfort University, Leicester, LE1 9BH (United Kingdom)] [Faculty of Health and Life Sciences, De Montfort University, Leicester, LE1 9BH (United Kingdom); Ikemura, Noriaki; Inoue, Kiyoshi; Miyataka, Hideki; Himeno, Seiichiro [Laboratory of Molecular Nutrition and Toxicology, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Tokushima 770–8514 (Japan)] [Laboratory of Molecular Nutrition and Toxicology, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Tokushima 770–8514 (Japan); Hossain, Khaled, E-mail: khossain69@yahoo.com [Department of Biochemistry and Molecular Biology, Rajshahi University, Rajshahi-6205 (Bangladesh)] [Department of Biochemistry and Molecular Biology, Rajshahi University, Rajshahi-6205 (Bangladesh)

    2012-03-01

    Chronic arsenic (As) exposure affects the endothelial system causing several diseases. Big endothelin-1 (Big ET-1), the biological precursor of endothelin-1 (ET-1) is a more accurate indicator of the degree of activation of the endothelial system. Effect of As exposure on the plasma Big ET-1 levels and its physiological implications have not yet been documented. We evaluated plasma Big ET-1 levels and their relation to hypertension and skin lesions in As exposed individuals in Bangladesh. A total of 304 study subjects from the As-endemic and non-endemic areas in Bangladesh were recruited for this study. As concentrations in water, hair and nails were measured by Inductively Coupled Plasma Mass Spectroscopy (ICP-MS). The plasma Big ET-1 levels were measured using a one-step sandwich enzyme immunoassay kit. Significant increase in Big ET-1 levels were observed with the increasing concentrations of As in drinking water, hair and nails. Further, before and after adjusting with different covariates, plasma Big ET-1 levels were found to be significantly associated with the water, hair and nail As concentrations of the study subjects. Big ET-1 levels were also higher in the higher exposure groups compared to the lowest (reference) group. Interestingly, we observed that Big ET-1 levels were significantly higher in the hypertensive and skin lesion groups compared to the normotensive and without skin lesion counterpart, respectively of the study subjects in As-endemic areas. Thus, this study demonstrated a novel dose–response relationship between As exposure and plasma Big ET-1 levels indicating the possible involvement of plasma Big ET-1 levels in As-induced hypertension and skin lesions. -- Highlights: ? Plasma Big ET-1 is an indicator of endothelial damage. ? Plasma Big ET-1 level increases dose-dependently in arsenic exposed individuals. ? Study subjects in arsenic-endemic areas with hypertension have elevated Big ET-1 levels. ? Study subjects with arsenic-induced skin lesions show elevated plasma Big ET-1 levels. ? Arsenic-induced hypertension and skin lesions may be linked to plasma Big ET-1 levels.

  16. High frequency inductive lamp and power oscillator

    DOE Patents [OSTI]

    MacLennan, Donald A. (Gaithersburg, MD); Turner, Brian P. (Damascus, MD); Dolan, James T. (Frederick, MD); Kirkpatrick, Douglas A. (Great Falls, VA); Leng, Yongzhang (Damascus, MD)

    2000-01-01

    A high frequency inductively coupled electrodeless lamp includes an excitation coil with an effective electrical length which is less than one half wavelength of a driving frequency applied thereto, preferably much less. The driving frequency may be greater than 100 MHz and is preferably as high as 915 MHz. Preferably, the excitation coil is configured as a non-helical, semi-cylindrical conductive surface having less than one turn, in the general shape of a wedding ring. At high frequencies, the current in the coil forms two loops which are spaced apart and parallel to each other. Configured appropriately, the coil approximates a Helmholtz configuration. The lamp preferably utilizes an bulb encased in a reflective ceramic cup with a pre-formed aperture defined therethrough. The ceramic cup may include structural features to aid in alignment and/or a flanged face to aid in thermal management. The lamp head is preferably an integrated lamp head comprising a metal matrix composite surrounding an insulating ceramic with the excitation integrally formed on the ceramic. A novel solid-state oscillator preferably provides RF power to the lamp. The oscillator is a single active element device capable of providing over 70 watts of power at over 70% efficiency. Various control circuits may be employed to match the driving frequency of the oscillator to a plurality of tuning states of the lamp.

  17. High frequency inductive lamp and power oscillator

    DOE Patents [OSTI]

    MacLennan, Donald A. (Gaithersburg, MD); Dymond, Jr., Lauren E. (North Potomac, MD); Gitsevich, Aleksandr (Montgomery Village, MD); Grimm, William G. (Silver Spring, MD); Kipling, Kent (Gaithersburg, MD); Kirkpatrick, Douglas A. (Great Falls, VA); Ola, Samuel A. (Silver Spring, MD); Simpson, James E. (Gaithersburg, MD); Trimble, William C. (Columbia, MD); Tsai, Peter (Olney, MD); Turner, Brian P. (Damascus, MD)

    2001-01-01

    A high frequency inductively coupled electrodeless lamp includes an excitation coil with an effective electrical length which is less than one half wavelength of a driving frequency applied thereto, preferably much less. The driving frequency may be greater than 100 MHz and is preferably as high as 915 MHz. Preferably, the excitation coil is configured as a non-helical, semi-cylindrical conductive surface having less than one turn, in the general shape of a wedding ring. At high frequencies, the current in the coil forms two loops which are spaced apart and parallel to each other. Configured appropriately, the coil approximates a Helmholtz configuration. The lamp preferably utilizes an bulb encased in a reflective ceramic cup with a pre-formed aperture defined therethrough. The ceramic cup may include structural features to aid in alignment and I or a flanged face to aid in thermal management. The lamp head is preferably an integrated lamp head comprising a metal matrix composite surrounding an insulating ceramic with the excitation integrally formed on the ceramic. A novel solid-state oscillator preferably provides RF power to the lamp. The oscillator is a single active element device capable of providing over 70 watts of power at over 70% efficiency. Various control circuits may be employed to adjust the driving frequency of the oscillator.

  18. Plasma valve

    DOE Patents [OSTI]

    Hershcovitch, Ady (Mount Sinai, NY); Sharma, Sushil (Hinsdale, IL); Noonan, John (Naperville, IL); Rotela, Elbio (Clarendon Hills, IL); Khounsary, Ali (Hinsdale, IL)

    2003-01-01

    A plasma valve includes a confinement channel and primary anode and cathode disposed therein. An ignition cathode is disposed adjacent the primary cathode. Power supplies are joined to the cathodes and anode for rapidly igniting and maintaining a plasma in the channel for preventing leakage of atmospheric pressure through the channel.

  19. Low inductance power electronics assembly

    DOE Patents [OSTI]

    Herron, Nicholas Hayden; Mann, Brooks S.; Korich, Mark D.; Chou, Cindy; Tang, David; Carlson, Douglas S.; Barry, Alan L.

    2012-10-02

    A power electronics assembly is provided. A first support member includes a first plurality of conductors. A first plurality of power switching devices are coupled to the first support member. A first capacitor is coupled to the first support member. A second support member includes a second plurality of conductors. A second plurality of power switching devices are coupled to the second support member. A second capacitor is coupled to the second support member. The first and second pluralities of conductors, the first and second pluralities of power switching devices, and the first and second capacitors are electrically connected such that the first plurality of power switching devices is connected in parallel with the first capacitor and the second capacitor and the second plurality of power switching devices is connected in parallel with the second capacitor and the first capacitor.

  20. Quantum entanglement and controlled logical gates using coupled SQUID flux qubits

    E-Print Network [OSTI]

    Zhou, Zhongyuan; Han, Siyuan; Chu, Shih-I

    2005-06-01

    We present an approach to realize universal two-bit quantum gates using two SQUID flux qubits. In this approach the basic unit consists of two inductively coupled SQUIDs with realistic device parameters. Quantum logical gates are implemented...

  1. Coupling Schemes in Terahertz Planar Metamaterials

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Roy Chowdhury, Dibakar; Singh, Ranjan; Taylor, Antoinette J.; Chen, Hou-Tong; Zhang, Weili; Azad, Abul K.

    2012-01-01

    We present a review of the different coupling schemes in a planar array of terahertz metamaterials. The gap-to-gap near-field capacitive coupling between split-ring resonators in a unit cell leads to either blue shift or red shift of the fundamental inductive-capacitive (LC) resonance, depending on the position of the split gap. The inductive coupling is enhanced by decreasing the inter resonator distance resulting in strong blue shifts of theLCresonance. We observe theLCresonance tuning only when the split-ring resonators are in close proximity of each other; otherwise, they appear to be uncoupled. Conversely, the higher-order resonances are sensitive to the smallest changemore »in the inter particle distance or split-ring resonator orientation and undergo tremendous resonance line reshaping giving rise to a sharp subradiant resonance mode which produces hot spots useful for sensing applications. Most of the coupling schemes in a metamaterial are based on a near-field effect, though there also exists a mechanism to couple the resonators through the excitation of lowest-order lattice mode which facilitates the long-range radiative or diffractive coupling in the split-ring resonator plane leading to resonance line narrowing of the fundamental as well as the higher order resonance modes.« less

  2. Induction slag reduction process for making titanium

    DOE Patents [OSTI]

    Traut, Davis E. (Corvallis, OR)

    1991-01-01

    Continuous process for preparing titanium comprising fluorinating titanium ore, and reducing the formed alkaline earth fluotitanate with an alkaline earth metal in an induction slag reactor.

  3. Localized Induction Equation for Stretched Vortex Filament

    E-Print Network [OSTI]

    Kimiaki Konno; Hiroshi Kakuhata

    2006-03-02

    We study numerically the motion of the stretched vortex filaments by using the localized induction equation with the stretch and that without the stretch.

  4. 164 INDUCTIVE LOGIC "Corroboration versus Induction," British Journal for the Philosophy of Science

    E-Print Network [OSTI]

    Fitelson, Branden

    164 INDUCTIVE LOGIC "Corroboration versus Induction," British Journal for the Philosophy of Science: D. C. Stove,review of Popper's, Logic of Scientij5c Discovery, AustralasianJournal of Philosophy 38 Measures of Evidential Strength" appears in Aspects of Inductive Logic (Hintikka and Suppes, eds.), North

  5. Princeton Plasma Physics Laboratory NSTX Experimental Proposal

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    Author: G. Taylor Date ATI ­ ET Group Leader: G. Taylor Date RLM - Run Coordinator: E. Fredrickson Date-Driven 100% Non-Inductive H-Mode Plasma No. OP-XP-1010 AUTHORS: G. Taylor, D. Mueller, J.C. Hosea, S. Gerhardt, C. Kessel, B.P. LeBlanc, C.K. Phillips, S. Zweben, R. Maingi, P.M. Ryan, R. Maingi DATE: February

  6. A Material Theory of Induction* John D. Nortonyz

    E-Print Network [OSTI]

    that there are no universal inductive inference schemas. The inductive inferences of science are grounded in matters of fact assess and control the inductive risk taken in an induction by investigating the warrant for its to be reconciled with our continued failure to agree on an explicit systematization of inductive inference

  7. Comparative Analysis of Carbon Plasma in Arc and RF Reactors

    SciTech Connect (OSTI)

    Todorovic-Markovic, B.; Markovic, Z.; Mohai, I.; Szepvolgyi, J.

    2004-12-01

    Results on studies of molecular spectra emitted in the initial stages of fullerene formation during the processing of graphite powder in induction RF reactor and evaporation of graphite electrodes in arc reactor are presented in this paper. It was found that C2 radicals were dominant molecular species in both plasmas. C2 radicals have an important role in the process of fullerene synthesis. The rotational-vibrational temperatures of C2 and CN species were calculated by fitting the experimental spectra to the simulated ones. The results of optical emission study of C2 radicals generated in carbon arc plasma have shown that rotational temperature of C2 species depends on carbon concentration and current intensity significantly. The optical emission study of induction RF plasma and SEM analysis of graphite powder before and after plasma treatment have shown that evaporation of the processed graphite powder depends on feed rate and composition of gas phase significantly. Based on the obtained results, it was concluded that in the plasma region CN radicals could be formed by the reaction of C2 species with atomic nitrogen at smaller loads. At larger feed rate of graphite powder, CN species were produced by surface reaction of the hot carbon particles with nitrogen atoms. The presence of nitrogen in induction RF plasma reduces the fullerene yield significantly. The fullerene yield obtained in two different reactors was: 13% in arc reactor and 4.1% in induction RF reactor. However, the fullerene production rate was higher in induction RF reactor-6.4 g/h versus 1.7 g/h in arc reactor.

  8. Implementation Techniques for Inductive Types in Plastic ?

    E-Print Network [OSTI]

    Luo, Zhaohui

    Implementation Techniques for Inductive Types in Plastic ? Paul Callaghan and Zhaohui Luo://www.dur.ac.uk/CARG fP.C.Callaghan, Zhaohui.Luog@durham.ac.uk Abstract. In the context of Plastic, a proof assistant the reduction mechanisms of Plastic, and briefly considers optimisations for inductive types. Key words: type

  9. A segmented multi-loop antenna for selective excitation of azimuthal mode number in a helicon plasma source

    SciTech Connect (OSTI)

    Shinohara, S.; Tanikawa, T.; Motomura, T.

    2014-09-15

    A flat type, segmented multi-loop antenna was developed in the Tokai Helicon Device, built for producing high-density helicon plasma, with a diameter of 20 cm and an axial length of 100 cm. This antenna, composed of azimuthally splitting segments located on four different radial positions, i.e., r = 2.8, 4.8, 6.8, and 8.8 cm, can excite the azimuthal mode number m of 0, ±1, and ±2 by a proper choice of antenna feeder parts just on the rear side of the antenna. Power dependencies of the electron density n{sub e} were investigated with a radio frequency (rf) power less than 3 kW (excitation frequency ranged from 8 to 20 MHz) by the use of various types of antenna segments, and n{sub e} up to ?5 × 10{sup 12} cm{sup ?3} was obtained after the density jump from inductively coupled plasma to helicon discharges. Radial density profiles of m = 0 and ±1 modes with low and high rf powers were measured. For the cases of these modes after the density jump, the excited mode structures derived from the magnetic probe measurements were consistent with those expected from theory on helicon waves excited in the plasma.

  10. Ramp-up of CHI Initiated Plasmas on NSTX

    SciTech Connect (OSTI)

    Mueller, D; Bell, R E; LeBlanc, B; Roquemore, A L; Raman, R; Jarboe, T R; Nelson, B A

    2009-10-29

    Experiments on the National Spherical Torus (NSTX) have now demonstrated flux savings using transient coaxial helicity injection (CHI). In these discharges, the discharges initiated by CHI are ramped up with an inductive transformer and exhibit higher plasma current than discharges without the benefit of CHI initiation.

  11. Bridget C. Ennevor Department of Fisheries and Oceans. 327-555 West Hastings Street

    E-Print Network [OSTI]

    of the vertebral column, otoliths, and scales by inductively coupled plasma-mass spectrom- etry (lCP-MS) revealed

  12. Cold atmospheric plasma in cancer therapy

    SciTech Connect (OSTI)

    Keidar, Michael; Shashurin, Alex; Volotskova, Olga; Ann Stepp, Mary; Srinivasan, Priya; Sandler, Anthony; Trink, Barry

    2013-05-15

    Recent progress in atmospheric plasmas has led to the creation of cold plasmas with ion temperature close to room temperature. This paper outlines recent progress in understanding of cold plasma physics as well as application of cold atmospheric plasma (CAP) in cancer therapy. Varieties of novel plasma diagnostic techniques were developed recently in a quest to understand physics of CAP. It was established that the streamer head charge is about 10{sup 8} electrons, the electrical field in the head vicinity is about 10{sup 7} V/m, and the electron density of the streamer column is about 10{sup 19} m{sup ?3}. Both in-vitro and in-vivo studies of CAP action on cancer were performed. It was shown that the cold plasma application selectively eradicates cancer cells in-vitro without damaging normal cells and significantly reduces tumor size in-vivo. Studies indicate that the mechanism of action of cold plasma on cancer cells is related to generation of reactive oxygen species with possible induction of the apoptosis pathway. It is also shown that the cancer cells are more susceptible to the effects of CAP because a greater percentage of cells are in the S phase of the cell cycle.

  13. Novel Manufacturing Technologies for High Power Induction and...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Manufacturing Technologies for High Power Induction and Permanent Magnet Electric Motors Novel Manufacturing Technologies for High Power Induction and Permanent Magnet Electric...

  14. Plasma-produced phase-pure cuprous oxide nanowires for methane gas sensing

    SciTech Connect (OSTI)

    Cheng, Qijin Zhang, Fengyan; Yan, Wei; Randeniya, Lakshman; Ostrikov, Kostya

    2014-03-28

    Phase-selective synthesis of copper oxide nanowires is warranted by several applications, yet it remains challenging because of the narrow windows of the suitable temperature and precursor gas composition in thermal processes. Here, we report on the room-temperature synthesis of small-diameter, large-area, uniform, and phase-pure Cu{sub 2}O nanowires by exposing copper films to a custom-designed low-pressure, thermally non-equilibrium, high-density (typically, the electron number density is in the range of 10{sup 11}–10{sup 13}?cm{sup ?3}) inductively coupled plasmas. The mechanism of the plasma-enabled phase selectivity is proposed. The gas sensors based on the synthesized Cu{sub 2}O nanowires feature fast response and recovery for the low-temperature (?140?°C) detection of methane gas in comparison with polycrystalline Cu{sub 2}O thin film-based gas sensors. Specifically, at a methane concentration of 4%, the response and the recovery times of the Cu{sub 2}O nanowire-based gas sensors are 125 and 147?s, respectively. The Cu{sub 2}O nanowire-based gas sensors have a potential for applications in the environmental monitoring, chemical industry, mining industry, and several other emerging areas.

  15. Electrochemical characteristics of plasma-etched black silicon as anodes for Li-ion batteries

    SciTech Connect (OSTI)

    Lee, Gibaek; Wehrspohn, Ralf B., E-mail: ralf.b.wehrspohn@iwmh.fraunhofer.de [Fraunhofer Institute for Mechanics of Materials IWM, Halle (Saale) 06120, Germany and Department of Physics, Martin-Luther University, Halle (Saale) 06099 (Germany); Schweizer, Stefan L. [Department of Physics, Martin-Luther University, Halle (Saale) 06099 (Germany)

    2014-11-01

    Nanostructured silicon as an anode material for Li-ion batteries is produced for the first time by inductively coupled plasma–plasma etching of Si wafers in the black silicon regime. The microscopic structure strongly resembles other types of nanostructured silicon, with a well-arranged nanostructure possessing a sufficient porosity for accommodating large volume expansion. Despite these features, however, a high first-cycle irreversible capacity loss and a poor cycle life are observed. The main reason for these poor features is the formation of a thick solid-electrolyte interphase (SEI) layer related to the surface condition of the pristine nanostructured black silicon (b-Si) electrode. Therefore, the cycle life of the b-Si electrode is heavily influenced by the constant reformation of the SEI layer depending upon the surface composition in spite of the presence of nanostructured Si. In the fast lithiation experiments, the nanostructure region of the b-Si electrode is detached from the Si substrate owing to the kinetics difference between the lithium ion diffusion and the electron injection and phase transformation in the nanostructured Si region. This means that more Si substrate is involved in lithiation at high current rates. It is therefore important to maintain balance in the chemical kinetics during the lithiation of nanostructured Si electrodes with a Si substrate.

  16. Microwave Excitation In ECRIS plasmas

    SciTech Connect (OSTI)

    Ciavola, G.; Celona, L.; Consoli, F.; Gammino, S.; Maimone, F.; Barbarino, S.; Catalano, R. S.; Mascali, D.; Tumino, L.

    2007-09-28

    A number of phenomena related to the electron cyclotron resonance ion sources (ECRIS) has been better understood recently by means of the improvement of comprehension of the coupling mechanism between microwave generators and ECR plasma. In particular, the two frequency heating and the frequency tuning effect, that permit a remarkable increase of the current for the highest charge states ions, can be explained in terms of modes excitation in the cylindrical cavity of the plasma chamber. Calculations based on this theoretical approach have been performed, and the major results will be presented. It will be shown that the electric field pattern completely changes for a few MHz frequency variations and the changes in ECRIS performances can be correlated to the efficiency of the power transfer between electromagnetic field and plasma.

  17. Thermoacoustic couple

    DOE Patents [OSTI]

    Wheatley, J.C.; Swift, G.W.; Migliori, A.

    1983-10-04

    An apparatus and method for determining acoustic power density level and its direction in a fluid using a single sensor are disclosed. The preferred embodiment of the apparatus, which is termed a thermoacoustic couple, consists of a stack of thin, spaced apart polymeric plates, selected ones of which include multiple bimetallic thermocouple junctions positioned along opposite end edges thereof. The thermocouple junctions are connected in series in the nature of a thermopile, and are arranged so as to be responsive to small temperature differences between the opposite edges of the plates. The magnitude of the temperature difference, as represented by the magnitude of the electrical potential difference generated by the thermopile, is found to be directly related to the level of acoustic power density in the gas.

  18. Polar caps in the presence of an induction field

    E-Print Network [OSTI]

    Jones, P B

    2015-01-01

    Following the early paper of Goldreich & Julian (1969), polar-cap models have usually assumed that the closed sector of a pulsar magnetosphere corotates with the neutron star. Recent work by Melrose & Yuen has been a reminder that in an oblique rotator, the induction field arising from the time-varying magnetic flux density cannot be completely screened. The principal consequence is that the plasma does not corotate with the star. Here it is shown that the physics of the polar cap is not changed at the altitudes of the radio emission source. But the presence of a plasma drift velocity in the corotating frame of reference does provide a mechanism whereby the net charge of the star can be maintained within a stable band of values. It also shows directly how electron injection and acceleration occur in the outer gap of the magnetosphere. It is consistent with radio-loud pulsars in the Fermi LAT catalogue of gamma-emitters all having positive polar-cap charge density.

  19. Method and apparatus for steady-state magnetic measurement of poloidal magnetic field near a tokamak plasma

    DOE Patents [OSTI]

    Woolley, R.D.

    1998-09-08

    A method and apparatus are disclosed for the steady-state measurement of poloidal magnetic field near a tokamak plasma, where the tokamak is configured with respect to a cylindrical coordinate system having z, phi (toroidal), and r axes. The method is based on combining the two magnetic field principles of induction and torque. The apparatus includes a rotor assembly having a pair of inductive magnetic field pickup coils which are concentrically mounted, orthogonally oriented in the r and z directions, and coupled to remotely located electronics which include electronic integrators for determining magnetic field changes. The rotor assembly includes an axle oriented in the toroidal direction, with the axle mounted on pivot support brackets which in turn are mounted on a baseplate. First and second springs are located between the baseplate and the rotor assembly restricting rotation of the rotor assembly about its axle, the second spring providing a constant tensile preload in the first spring. A strain gauge is mounted on the first spring, and electronic means to continually monitor strain gauge resistance variations is provided. Electronic means for providing a known current pulse waveform to be periodically injected into each coil to create a time-varying torque on the rotor assembly in the toroidal direction causes mechanical strain variations proportional to the torque in the mounting means and springs so that strain gauge measurement of the variation provides periodic magnetic field measurements independent of the magnetic field measured by the electronic integrators. 6 figs.

  20. Method and apparatus for steady-state magnetic measurement of poloidal magnetic field near a tokamak plasma

    DOE Patents [OSTI]

    Woolley, Robert D. (Hillsborough, NJ)

    1998-01-01

    A method and apparatus for the steady-state measurement of poloidal magnetic field near a tokamak plasma, where the tokamak is configured with respect to a cylindrical coordinate system having z, phi (toroidal), and r axes. The method is based on combining the two magnetic field principles of induction and torque. The apparatus includes a rotor assembly having a pair of inductive magnetic field pickup coils which are concentrically mounted, orthogonally oriented in the r and z directions, and coupled to remotely located electronics which include electronic integrators for determining magnetic field changes. The rotor assembly includes an axle oriented in the toroidal direction, with the axle mounted on pivot support brackets which in turn are mounted on a baseplate. First and second springs are located between the baseplate and the rotor assembly restricting rotation of the rotor assembly about its axle, the second spring providing a constant tensile preload in the first spring. A strain gauge is mounted on the first spring, and electronic means to continually monitor strain gauge resistance variations is provided. Electronic means for providing a known current pulse waveform to be periodically injected into each coil to create a time-varying torque on the rotor assembly in the toroidal direction causes mechanical strain variations proportional to the torque in the mounting means and springs so that strain gauge measurement of the variation provides periodic magnetic field measurements independent of the magnetic field measured by the electronic integrators.

  1. Matching network for RF plasma source

    DOE Patents [OSTI]

    Pickard, Daniel S. (Palo Alto, CA); Leung, Ka-Ngo (Hercules, CA)

    2007-11-20

    A compact matching network couples an RF power supply to an RF antenna in a plasma generator. The simple and compact impedance matching network matches the plasma load to the impedance of a coaxial transmission line and the output impedance of an RF amplifier at radio frequencies. The matching network is formed of a resonantly tuned circuit formed of a variable capacitor and an inductor in a series resonance configuration, and a ferrite core transformer coupled to the resonantly tuned circuit. This matching network is compact enough to fit in existing compact focused ion beam systems.

  2. PPPL3252 Preprint: June 1997, UC420, 427 Role of Plasma Edge in the Direct Launch Ion

    E-Print Network [OSTI]

    installed in Tokamak Fusion Test Reactor (TFTR) to test a concept of generating sheared flow 2 in order efficiency for the core deposition. In order to launch IBW, it is necessary to first couple to cold plasma that it is difficult to couple directly. There are two cold plasma waves which can couple directly to IBW, namely

  3. PPPL-3252 -Preprint: June 1997, UC-420, 427 Role of Plasma Edge in the Direct Launch Ion

    E-Print Network [OSTI]

    in Tokamak Fusion Test Reactor (TFTR) to test a concept of generating sheared flow2 in order to trigger efficiency for the core deposition. In order to launch IBW, it is necessary to first couple to cold plasma that it is difficult to couple directly. There are two cold plasma waves which can couple directly to IBW, namely

  4. Holographic Jets in an Expanding Plasma

    E-Print Network [OSTI]

    Alexander Stoffers; Ismail Zahed

    2012-11-19

    We use the holographic principle to study quark jets with trailing strings in an expanding plasma that asymptotes Bjorken hydrodynamics. We make use of the fact that the trailing string is the locus of the light delay in bulk to obtain the explicit form for quark jets in the expanding plasma. From the trailing string solution we calculate the drag coefficient of a heavy quark in the strongly coupled expanding plasma. The energy scaling of the maximum penetration length of an ultrarelativistic light quark jet using light rays in bulk is estimated.

  5. Multi-Scale Investigation of Sheared Flows In Magnetized Plasmas

    SciTech Connect (OSTI)

    Edward, Jr., Thomas

    2014-09-19

    Flows parallel and perpendicular to magnetic fields in a plasma are important phenomena in many areas of plasma science research. The presence of these spatially inhomogeneous flows is often associated with the stability of the plasma. In fusion plasmas, these sheared flows can be stabilizing while in space plasmas, these sheared flows can be destabilizing. Because of this, there is broad interest in understanding the coupling between plasma stability and plasma flows. This research project has engaged in a study of the plasma response to spatially inhomogeneous plasma flows using three different experimental devices: the Auburn Linear Experiment for Instability Studies (ALEXIS) and the Compact Toroidal Hybrid (CTH) stellarator devices at Auburn University, and the Space Plasma Simulation Chamber (SPSC) at the Naval Research Laboratory. This work has shown that there is a commonality of the plasma response to sheared flows across a wide range of plasma parameters and magnetic field geometries. The goal of this multi-device, multi-scale project is to understand how sheared flows established by the same underlying physical mechanisms lead to different plasma responses in fusion, laboratory, and space plasmas.

  6. Experimental characterization of a coaxial plasma accelerator for a colliding plasma experiment

    SciTech Connect (OSTI)

    Wiechula, J.; Hock, C.; Iberler, M.; Manegold, T.; Schönlein, A.; Jacoby, J.

    2015-04-15

    We report experimental results of a single coaxial plasma accelerator in preparation for a colliding plasma experiment. The utilized device consisted of a coaxial pair of electrodes, accelerating the plasma due to J×B forces. A pulse forming network, composed of three capacitors connected in parallel, with a total capacitance of 27??F was set up. A thyratron allowed to switch the maximum applied voltage of 9?kV. Under these conditions, the pulsed currents reached peak values of about 103?kA. The measurements were performed in a small vacuum chamber with a neutral-gas prefill at gas pressures between 10?Pa and 14?000?Pa. A gas mixture of ArH{sub 2} with 2.8% H{sub 2} served as the discharge medium. H{sub 2} was chosen in order to observe the broadening of the H{sub ?} emission line and thus estimate the electron density. The electron density for a single plasma accelerator reached peak values on the order of 10{sup 16}?cm{sup ?3}. Electrical parameters, inter alia inductance and resistance, were determined for the LCR circuit during the plasma acceleration as well as in a short circuit case. Depending on the applied voltage, the inductance and resistance reached values ranging from 194 nH to 216 nH and 13 m? to 23 m?, respectively. Furthermore, the plasma velocity was measured using a fast CCD camera. Plasma velocities of 2?km/s up to 17?km/s were observed, the magnitude being highly correlated with gas pressure and applied voltage.

  7. Effect of dielectric barrier discharge plasma actuators on non-equilibrium hypersonic Ankush Bhatia, Subrata Roy, and Ryan Gosse

    E-Print Network [OSTI]

    Roy, Subrata

    flow velocity on momentum transfer of dielectric barrier discharge plasma actuators J. Appl. Phys. 116. Phys. 113, 243302 (2013); 10.1063/1.4809975 Momentum transfer and flow induction in a dielectric.1063/1.3682488 Modeling plasma actuators with air chemistry for effective flow control J. Appl. Phys. 101, 123308 (2007

  8. J. Plasma Physics: page 1 of 6. c Cambridge University Press 2014 doi:10.1017/S0022377814000270

    E-Print Network [OSTI]

    Merlino, Robert L.

    microparticles and the surrounding plasma are intimately coupled to each other. The origins of dusty plasma research began more than three decades ago. At that time, much of the emphasis was placed upon

  9. Parton Energy Loss in Two-Stream Plasma System

    E-Print Network [OSTI]

    M. E. Carrington; K. Deja; St. Mrowczynski

    2012-01-06

    The energy loss of a fast parton scattering elastically in a weakly coupled quark-gluon plasma is formulated as an initial value problem. The approach is designed to study an unstable plasma, but it also reproduces the well known result of energy loss in an equilibrium plasma. A two-stream system, which is unstable due to longitudinal chromoelectric modes, is discussed here some detail. In particular, a strong time and directional dependence of the energy loss is demonstrated.

  10. Numerical simulation of alumina spraying in argon-helium plasma jet

    SciTech Connect (OSTI)

    Chang, C.H.

    1992-01-01

    A new numerical model is described for simulating thermal plasmas containing entrained particles, with emphasis on plasma spraying applications. The plasma is represented as a continuum multicomponent chemically reacting ideal gas, while the particles are tracked as discrete Lagrangian entities coupled to the plasma. Computational results are presented from a transient simulation of alumina spraying in a turbulent argon-helium plasma jet in air environment, including torch geometry, substrate, and multiple species with chemical reactions. Particle-plasma interactions including turbulent dispersion have been modeled in a fully self-consistent manner. Interactions between the plasma and the torch and substrate walls are modeled using wall functions. (15 refs.)

  11. Numerical simulation of alumina spraying in argon-helium plasma jet

    SciTech Connect (OSTI)

    Chang, C.H.

    1992-08-01

    A new numerical model is described for simulating thermal plasmas containing entrained particles, with emphasis on plasma spraying applications. The plasma is represented as a continuum multicomponent chemically reacting ideal gas, while the particles are tracked as discrete Lagrangian entities coupled to the plasma. Computational results are presented from a transient simulation of alumina spraying in a turbulent argon-helium plasma jet in air environment, including torch geometry, substrate, and multiple species with chemical reactions. Particle-plasma interactions including turbulent dispersion have been modeled in a fully self-consistent manner. Interactions between the plasma and the torch and substrate walls are modeled using wall functions. (15 refs.)

  12. Photo-assisted etching of silicon in chlorine- and bromine-containing plasmas

    SciTech Connect (OSTI)

    Zhu, Weiye; Sridhar, Shyam; Liu, Lei; Hernandez, Eduardo; Donnelly, Vincent M. Economou, Demetre J.

    2014-05-28

    Cl{sub 2}, Br{sub 2}, HBr, Br{sub 2}/Cl{sub 2}, and HBr/Cl{sub 2} feed gases diluted in Ar (50%–50% by volume) were used to study etching of p-type Si(100) in a rf inductively coupled, Faraday-shielded plasma, with a focus on the photo-assisted etching component. Etching rates were measured as a function of ion energy. Etching at ion energies below the threshold for ion-assisted etching was observed in all cases, with Br{sub 2}/Ar and HBr/Cl{sub 2}/Ar plasmas having the lowest and highest sub-threshold etching rates, respectively. Sub-threshold etching rates scaled with the product of surface halogen coverage (measured by X-ray photoelectron spectroscopy) and Ar emission intensity (7504?Å). Etching rates measured under MgF{sub 2}, quartz, and opaque windows showed that sub-threshold etching is due to photon-stimulated processes on the surface, with vacuum ultraviolet photons being much more effective than longer wavelengths. Scanning electron and atomic force microscopy revealed that photo-etched surfaces were very rough, quite likely due to the inability of the photo-assisted process to remove contaminants from the surface. Photo-assisted etching in Cl{sub 2}/Ar plasmas resulted in the formation of 4-sided pyramidal features with bases that formed an angle of 45° with respect to ?110? cleavage planes, suggesting that photo-assisted etching can be sensitive to crystal orientation.

  13. Miniaturized cathodic arc plasma source

    DOE Patents [OSTI]

    Anders, Andre (Albany, CA); MacGill, Robert A. (Richmond, CA)

    2003-04-15

    A cathodic arc plasma source has an anode formed of a plurality of spaced baffles which extend beyond the active cathode surface of the cathode. With the open baffle structure of the anode, most macroparticles pass through the gaps between the baffles and reflect off the baffles out of the plasma stream that enters a filter. Thus the anode not only has an electrical function but serves as a prefilter. The cathode has a small diameter, e.g. a rod of about 1/4 inch (6.25 mm) diameter. Thus the plasma source output is well localized, even with cathode spot movement which is limited in area, so that it effectively couples into a miniaturized filter. With a small area cathode, the material eroded from the cathode needs to be replaced to maintain plasma production. Therefore, the source includes a cathode advancement or feed mechanism coupled to cathode rod. The cathode also requires a cooling mechanism. The movable cathode rod is housed in a cooled metal shield or tube which serves as both a current conductor, thus reducing ohmic heat produced in the cathode, and as the heat sink for heat generated at or near the cathode. Cooling of the cathode housing tube is done by contact with coolant at a place remote from the active cathode surface. The source is operated in pulsed mode at relatively high currents, about 1 kA. The high arc current can also be used to operate the magnetic filter. A cathodic arc plasma deposition system using this source can be used for the deposition of ultrathin amorphous hard carbon (a-C) films for the magnetic storage industry.

  14. Plasma Physics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass mapSpeeding access| DepartmentPeerFederal FleetUpSmall WindPrinceton PlasmaFlow

  15. Induction linacs for heavy ion fusion research

    SciTech Connect (OSTI)

    Fessenden, T.J.

    1984-05-01

    The new features of employing an induction linac as a driver for inertial fusion involve (1) transport of high-current low-emittance heavy ion beams, (2) multiple independently-focussed beams threading the same accelerator structure, and (3) synthesis of voltage waveforms to accomplish beam current amplification. A research program is underway at LBL to develop accelerators that test all these features with the final goal of producing an ion beam capable of heating matter to approx. 70 eV. This paper presents a discussion of some properties of induction linacs and how they may be used for HIF research. Physics designs of the High Temperature Experiment (HTE) and the Multiple Beam Experiment (MBE) accelerators are presented along with initial concepts of the MBE induction units.

  16. DOI: 10.1002/cvde.200606508 Plasma-Enhanced Atomic Layer Deposition of Palladium

    E-Print Network [OSTI]

    Wang, Gwo-Ching

    DOI: 10.1002/cvde.200606508 Full Paper Plasma-Enhanced Atomic Layer Deposition of Palladium, and Gwo-Ching Wang In this paper, a method for the plasma-enhanced (PE) atomic layer deposition (ALD is successfully deposited on PPX at 80 °C using a remote, in- ductively coupled, hydrogen/nitrogen plasma

  17. An Analysis of Energy Balance in a Helicon Plasma Source for Space Propulsion

    E-Print Network [OSTI]

    An Analysis of Energy Balance in a Helicon Plasma Source for Space Propulsion by Justin Matthew;An Analysis of Energy Balance in a Helicon Plasma Source for Space Propulsion by Justin Matthew Pucci are optical radiation emission, wall losses due to poor magnetic confinement, and poor antenna-plasma coupling

  18. Inaugural Lecture: The Warrant of Induction

    E-Print Network [OSTI]

    Mellor, David Hugh

    1988-01-21

    fatigue and caterpillars turning into butterflies are two more obvious examples. But we recognise them inductively. Our mortality statistics show that the observed chances of adults surviving another year have so far always or nearly always decreased... , or almost none, of the many lectures, on all subjects, which you've heard or heard of, have lasted that long. If many of them had, you wouldn't have known that this one won't; but as it is, you do know that. That's a piece of induction. We believe...

  19. Plasma generators, reactor systems and related methods

    DOE Patents [OSTI]

    Kong, Peter C. (Idaho Falls, ID); Pink, Robert J. (Pocatello, ID); Lee, James E. (Idaho Falls, ID)

    2007-06-19

    A plasma generator, reactor and associated systems and methods are provided in accordance with the present invention. A plasma reactor may include multiple sections or modules which are removably coupled together to form a chamber. Associated with each section is an electrode set including three electrodes with each electrode being coupled to a single phase of a three-phase alternating current (AC) power supply. The electrodes are disposed about a longitudinal centerline of the chamber and are arranged to provide and extended arc and generate an extended body of plasma. The electrodes are displaceable relative to the longitudinal centerline of the chamber. A control system may be utilized so as to automatically displace the electrodes and define an electrode gap responsive to measure voltage or current levels of the associated power supply.

  20. Apparatus for recording emissions from a rapidly generated plasma from a single plasma producing event

    DOE Patents [OSTI]

    Tan, Tai Ho (Los Alamos, NM); Williams, Arthur H. (Los Alamos, NM)

    1985-01-01

    An optical fiber-coupled detector visible streak camera plasma diagnostic apparatus. Arrays of optical fiber-coupled detectors are placed on the film plane of several types of particle, x-ray and visible spectrometers or directly in the path of the emissions to be measured and the output is imaged by a visible streak camera. Time and spatial dependence of the emission from plasmas generated from a single pulse of electromagnetic radiation or from a single particle beam burst can be recorded.

  1. Dynamic dipole polarizability of Li{sup +} embedded in plasmas

    SciTech Connect (OSTI)

    Kar, S., E-mail: skar@hit.edu.cn [Center for Theoretical Atomic and Molecular Physics, The Academy of Fundamental and Interdisciplinary Sciences, Harbin Institute of Technology, Harbin 150080, People's Republic of China and Institute of Mathematical Sciences, University of Malaya, Ku (Malaysia); Kamali, M. Z. M., E-mail: Mzmk200@yahoo.com [Centre for Foundation Studies in Science, University of Malaya, Kuala Lumpur (Malaysia); Ratnavelu, K., E-mail: Kururatan2012@gmail.com [Institute of Mathematical Sciences, University of Malaya, Kuala Lumpur (Malaysia)

    2014-03-05

    Dynamic dipole polarizabilities of the system Li{sup +} embedded in weakly coupled plasmas are investigated using highly correlated exponential wave functions in the framework of the pseudostate summation technique. The Debye-Hückel shielding approach of plasma modeling is used to represent weakly coupled plasma environment. In free-atomic cases, results obtained from the present study are in agreement with the available calculations. Frequency-dependent polarizability of Li{sup +} as function of screening parameter is presented for the first time. Resonance frequencies for Li{sup +} are also presented in terms of screening parameter.

  2. Beam Compression in Heavy-Ion Induction Linacs

    E-Print Network [OSTI]

    Seidl, P.A.

    2009-01-01

    with RF and cathodic-arc plasma sources [4]. Thissource [5], and cathodic arc plasma sources injected a high-in that range with cathodic-arc plasma sources. The plasma

  3. Voltage regulation in linear induction accelerators

    DOE Patents [OSTI]

    Parsons, W.M.

    1992-12-29

    Improvement in voltage regulation in a linear induction accelerator wherein a varistor, such as a metal oxide varistor, is placed in parallel with the beam accelerating cavity and the magnetic core is disclosed. The non-linear properties of the varistor result in a more stable voltage across the beam accelerating cavity than with a conventional compensating resistance. 4 figs.

  4. Voltage regulation in linear induction accelerators

    DOE Patents [OSTI]

    Parsons, William M. (Santa Fe, NM)

    1992-01-01

    Improvement in voltage regulation in a Linear Induction Accelerator wherein a varistor, such as a metal oxide varistor, is placed in parallel with the beam accelerating cavity and the magnetic core. The non-linear properties of the varistor result in a more stable voltage across the beam accelerating cavity than with a conventional compensating resistance.

  5. Control System Synthesis Through Inductive Learning

    E-Print Network [OSTI]

    Antsaklis, Panos

    Control System Synthesis Through Inductive Learning of Boolean Concepts Michael Lemmon, Panos the use of concept learning in the identification of discrete event system (DES) controllers. Introduction of bounded process uncertainty. If the resulting performance of the robust control system is unacceptable

  6. Global Electrical Conductivity Magnetic Satellite Induction Studies

    E-Print Network [OSTI]

    Constable, Steve

    CHAMPMeeting, September2003 c S.Constable SCRIPPSINST ITUTION OF OCE ANOGRAPHY UCSD #12;Contents: · Background: Earth conductivity · Background: EM induction · Some satellite results 2ndCHAMPMeeting, September2003 c SCHAMPMeeting, September2003 c S.Constable SCRIPPSINST ITUTION OF OCE ANOGRAPHY UCSD #12;Conductivity of Earth materials

  7. Local Constructive Set Theory and Inductive Definitions

    E-Print Network [OSTI]

    Aczel, Peter

    Local Constructive Set Theory and Inductive Definitions Peter Aczel 1 Introduction Local Constructive Set Theory (LCST) is intended to be a local version of con- structive set theory (CST principles, is also acceptable in topos mathematics, the mathematics that can be carried out in an arbi

  8. Rigorous theory of nuclear fusion rates in a plasma

    E-Print Network [OSTI]

    Lowell S. Brown; David C. Dooling; Dean L. Preston

    2005-09-22

    Real-time thermal field theory is used to reveal the structure of plasma corrections to nuclear reactions. Previous results are recovered in a fashion that clarifies their nature, and new extensions are made. Brown and Yaffe have introduced the methods of effective quantum field theory into plasma physics. They are used here to treat the interesting limiting case of dilute but very highly charged particles reacting in a dilute, one-component plasma. The highly charged particles are very strongly coupled to this background plasma. The effective field theory proves that this mean field solution plus the one-loop term dominate; higher loop corrections are negligible even though the problem involves strong coupling. Such analytic results for very strong coupling are rarely available, and they can serve as benchmarks for testing computer models.

  9. The Dynamic Creation of Induction Rules Using Proof Planning 

    E-Print Network [OSTI]

    Gow, Jeremy

    A key problem in automating proof by mathematical induction is choosing an induction rule suitable for a given conjecture. Since Boyer & Moore’s NQTHM system the standard approach has been based on recursion analysis, ...

  10. Excitation and control of a high-speed induction generator

    E-Print Network [OSTI]

    Englebretson, Steven Carl

    2005-01-01

    This project investigates the use of a high speed, squirrel cage induction generator and power converter for producing DC electrical power onboard ships and submarines. Potential advantages of high speed induction generators ...

  11. Semantic Taxonomy Induction from Heterogenous Evidence Computer Science Department

    E-Print Network [OSTI]

    Ng, Andrew Y.

    Semantic Taxonomy Induction from Heterogenous Evidence Rion Snow Computer Science Department­ tic taxonomies. Previous algorithms for taxonomy induction have typically focused on independent over heterogenous relationships to optimize the entire structure of the taxonomy, using knowl­ edge

  12. Semantic Taxonomy Induction from Heterogenous Evidence Computer Science Department

    E-Print Network [OSTI]

    Ng, Andrew Y.

    Semantic Taxonomy Induction from Heterogenous Evidence Rion Snow Computer Science Department- tic taxonomies. Previous algorithms for taxonomy induction have typically focused on independent over heterogenous relationships to optimize the entire structure of the taxonomy, using knowl- edge

  13. Induction Lighting: An Old Lighting Technology Made New Again

    Broader source: Energy.gov [DOE]

    Induction lighting is one of the best kept secrets in energy-efficient lighting. Simply stated, induction lighting is essentially a fluorescent light without electrodes or filaments, the items that...

  14. Magnetic induction systems to harvest energy from mechanical vibrations

    E-Print Network [OSTI]

    Jonnalagadda, Aparna S

    2007-01-01

    This thesis documents the design process for magnetic induction systems to harvest energy from mechanical vibrations. Two styles of magnetic induction systems - magnet-through-coil and magnet-across-coils - were analyzed. ...

  15. Plasma momentum meter for momentum flux measurements

    DOE Patents [OSTI]

    Zonca, F.; Cohen, S.A.; Bennett, T.; Timberlake, J.R.

    1993-08-24

    An apparatus is described for measuring momentum flux from an intense plasma stream, comprising: refractory target means oriented normal to the flow of said plasma stream for bombardment by said plasma stream where said bombardment by said plasma stream applies a pressure to said target means, pendulum means for communicating a translational displacement of said target to a force transducer where said translational displacement of said target is transferred to said force transducer by an elongated member coupled to said target, where said member is suspended by a pendulum configuration means and where said force transducer is responsive to said translational displacement of said member, and force transducer means for outputting a signal representing pressure data corresponding to said displacement.

  16. Fast wave evanescence in filamentary boundary plasmas

    SciTech Connect (OSTI)

    Myra, J. R. [Lodestar Research Corporation, Boulder, Colorado 80027 (United States)] [Lodestar Research Corporation, Boulder, Colorado 80027 (United States)

    2014-02-15

    Radio frequency waves for heating and current drive of plasmas in tokamaks and other magnetic confinement devices must first traverse the scrape-off-layer (SOL) before they can be put to their intended use. The SOL plasma is strongly turbulent and intermittent in space and time. These turbulent properties of the SOL, which are not routinely taken into account in wave propagation codes, can have an important effect on the coupling of waves through an evanescent SOL or edge plasma region. The effective scale length for fast wave (FW) evanescence in the presence of short-scale field-aligned filamentary plasma turbulence is addressed in this paper. It is shown that although the FW wavelength or evanescent scale length is long compared with the dimensions of the turbulence, the FW does not simply average over the turbulent density; rather, the average is over the exponentiation rate. Implications for practical situations are discussed.

  17. Observables in Strongly Coupled Anisotropic Theories

    E-Print Network [OSTI]

    Dimitrios Giataganas

    2013-12-30

    We review certain anisotropic gauge/gravity dualities, focusing more on a theory with space dependent axion term. Then we discuss and also present some new results for several observables: the static potential and force, the imaginary part of the static potential, the quark dipole in the plasma wind, the drag force and diffusion time, the jet quenching of heavy and light quarks, the energy loss of rotating quarks, the photon production and finally the violation of the holographic viscosity over entropy bound. The corresponding weakly coupled results are also discussed. Finally we investigate the bounds of the parameters of the current strongly coupled anisotropic theories attempting to match them with the observed quark-gluon plasma and report the problems appear.

  18. Dissipative and non-dissipative solitons in the SRS- backscattering of laser radiation in underdense plasma

    SciTech Connect (OSTI)

    Smetanin, Igor V. [P. N. Lebedev Physical Institute, Leninskii prosp. 53, 119991 Moscow (Russian Federation)

    2012-07-11

    The process of stimulated Raman backscattering of laser pulse in underdense plasma is considered self-consistently in 1D model. Solutions to this problem in the form of backward-propagating bright solitons (the Stokes scattered pulse and the plasma density wave) coupled with the dark soliton in the pump laser pulse are found. These solitary solutions exist both in the non-dissipative (non-collisional plasma) case and in the dissipative (collisional plasma) case.

  19. Polished Downhole Transducer Having Improved Signal Coupling

    DOE Patents [OSTI]

    Hall, David R. (Provo, UT); Fox, Joe (Spanish Fork, UT)

    2006-03-28

    Apparatus and methods to improve signal coupling in downhole inductive transmission elements to reduce the dispersion of magnetic energy at the tool joints and to provide consistent impedance and contact between transmission elements located along the drill string. A transmission element for transmitting information between downhole tools is disclosed in one embodiment of the invention as including an annular core constructed of a magnetically conductive material. The annular core forms an open channel around its circumference and is configured to form a closed channel by mating with a corresponding annular core along an annular mating surface. The mating surface is polished to provide improved magnetic coupling with the corresponding annular core. An annular conductor is disposed within the open channel.

  20. Anomalous radial transport in tokamak edge plasma

    E-Print Network [OSTI]

    Bodi, Vasudeva Raghavendra Kowsik

    2010-01-01

    Transport in tokamak plasma . . . . . . . . . . . . . . .Numerical simulations of tokamak plasma . . . . . . . . .of blobs in tokamak edge plasmas . . . . . . . . . . . . . .

  1. Collective flow of photons in strongly coupled gauge theories

    E-Print Network [OSTI]

    Yang, Di-Lun

    2015-01-01

    We investigate the shear viscosity of photons in a strongly coupled quark gluon plasma (QGP). We find that the shear viscosity due to the photon-parton scattering up to the leading order of electromagnetic coupling is suppressed when the coupling of the QGP is increased, which stems from the blue-shift of the thermal-photon spectrum at strong coupling. In addition, the shear viscosity rapidly increases near the deconfinement transition. We argue that the suppression of the photon shear viscosity in the QGP phase could lead to an enhancement of the anisotropic flow of direct photons in heavy ion collisions.

  2. Path Coupling and Aggregate Path Coupling

    E-Print Network [OSTI]

    Kovchegov, Yevgeniy

    2015-01-01

    In this survey paper, we describe and characterize an extension to the classical path coupling method applied statistical mechanical models, referred to as aggregate path coupling. In conjunction with large deviations estimates, we use this aggregate path coupling method to prove rapid mixing of Glauber dynamics for a large class of statistical mechanical models, including models that exhibit discontinuous phase transitions which have traditionally been more difficult to analyze rigorously. The parameter region for rapid mixing for the generalized Curie-Weiss-Potts model is derived as a new application of the aggregate path coupling method.

  3. Path Coupling and Aggregate Path Coupling

    E-Print Network [OSTI]

    Yevgeniy Kovchegov; Peter T. Otto

    2015-01-13

    In this survey paper, we describe and characterize an extension to the classical path coupling method applied statistical mechanical models, referred to as aggregate path coupling. In conjunction with large deviations estimates, we use this aggregate path coupling method to prove rapid mixing of Glauber dynamics for a large class of statistical mechanical models, including models that exhibit discontinuous phase transitions which have traditionally been more difficult to analyze rigorously. The parameter region for rapid mixing for the generalized Curie-Weiss-Potts model is derived as a new application of the aggregate path coupling method.

  4. Toroidal midplane neutral beam armor and plasma limiter

    DOE Patents [OSTI]

    Kugel, Henry W. (Somerset, NJ); Hand, Jr, Samuel W. (Hopewell Township, Mercer County, NJ); Ksayian, Haig (Titusville, NJ)

    1986-01-01

    For use in a tokamak fusion reactor having a midplane magnetic coil on the inner wall of an evacuated toriodal chamber within which a neutral beam heated, fusing plasma is magnetically confined, a neutral beam armor shield and plasma limiter is provided on the inner wall of the toroidal chamber to shield the midplane coil from neutral beam shine-thru and plasma deposition. The armor shield/plasma limiter forms a semicircular enclosure around the midplane coil with the outer surface of the armor shield/plasma limiter shaped to match, as closely as practical, the inner limiting magnetic flux surface of the toroidally confined, indented, bean-shaped plasma. The armor shield/plasma limiter includes a plurality of semicircular graphite plates each having a pair of coupled upper and lower sections with each plate positioned in intimate contact with an adjacent plate on each side thereof so as to form a closed, planar structure around the entire outer periphery of the circular midplane coil. The upper and lower plate sections are adapted for coupling to heat sensing thermocouples and to a circulating water conduit system for cooling the armor shield/plasma limiter.The inner center portion of each graphite plate is adapted to receive and enclose a section of a circular diagnostic magnetic flux loop so as to minimize the power from the plasma confinement chamber incident upon the flux loop.

  5. Circuit level modeling of inductive elements

    SciTech Connect (OSTI)

    Muyshondt, G.P.; Portnoy, W.M.

    1989-01-01

    Design and analysis of spacecraft power systems have been difficult to perform because of the lack of circuit level models for nonlinear inductive elements. This paper reviews some of the models which have been proposed, their limitations, and applications. An improved saturation dependent model will be described. The model has been implemented in SPICE and with a commercial circuit program and demonstrated to be satisfactory in both implementations. 3 refs., 9 figs.

  6. Cooling a quantum circuit via coupling to a multiqubit system

    E-Print Network [OSTI]

    Mihai A. Macovei

    2010-04-19

    The cooling effects of a quantum LC circuit coupled inductively with an ensemble of artificial qubits are investigated. The particles may decay independently or collectively through their interaction with the environmental vacuum electromagnetic field reservoir. For appropriate bath temperatures and the resonator's quality factors, we demonstrate an effective cooling well below the thermal background. In particular, we found that for larger samples the cooling efficiency is better for independent qubits. However, the cooling process can be faster for collectively interacting particles.

  7. Low pass filter for plasma discharge

    DOE Patents [OSTI]

    Miller, Paul A. (Albuquerque, NM)

    1994-01-01

    An isolator is disposed between a plasma reactor and its electrical energy source in order to isolate the reactor from the electrical energy source. The isolator operates as a filter to attenuate the transmission of harmonics of a fundamental frequency of the electrical energy source generated by the reactor from interacting with the energy source. By preventing harmonic interaction with the energy source, plasma conditions can be readily reproduced independent of the electrical characteristics of the electrical energy source and/or its associated coupling network.

  8. Action principle for Coulomb collisions in plasmas

    E-Print Network [OSTI]

    Hirvijoki, Eero

    2015-01-01

    In this letter we derive an action principle for Coulomb collisions in plasmas. Although no natural Lagrangian exists for the Landau-Fokker-Planck equation, an Eulerian variational formulation is found considering the system of partial differential equations that couple the distribution function and the Rosenbluth potentials. Exact conservation laws are derived after generalizing the energy-momentum stress tensor for second order Lagrangians and, in the case of a test-particle population in a given plasma background, the action principle is shown to correspond to the Langevin equation for individual particles. Being suitable for discretization, the presented action allows construction of variational integrators. Numerical implementation is left for a future study.

  9. Improved performance in long-pulse ELMy H-mode plasmas

    E-Print Network [OSTI]

    and fast ion losses Improvement of ELMy H-mode performance ­ Extension of sustained time duration of high NImproved performance in long-pulse ELMy H-mode plasmas with internal transport barrier in JT-60U N with large non- inductive current should be sustained longer than R. Sustainability of ITB, which drives

  10. Ising interaction between capacitively-coupled superconducting flux qubits

    E-Print Network [OSTI]

    Takahiko Satoh; Yuichiro Matsuzaki; Kosuke Kakuyanagi; Koichi Semba; Hiroshi Yamaguchi; Shiro Saito

    2015-01-30

    Here, we propose a scheme to generate a controllable Ising interaction between superconducting flux qubits. Existing schemes rely on inducting couplings to realize Ising interactions between flux qubits, and the interaction strength is controlled by an applied magnetic field On the other hand, we have found a way to generate an interaction between the flux qubits via capacitive couplings. This has an advantage in individual addressability, because we can control the interaction strength by changing an applied voltage that can be easily localized. This is a crucial step toward the realizing superconducting flux qubit quantum computation.

  11. Nonlinear plasma wave in magnetized plasmas

    SciTech Connect (OSTI)

    Bulanov, Sergei V.; Prokhorov Institute of General Physics, Russian Academy of Sciences, Moscow 119991; Moscow Institute of Physics and Technology, Dolgoprudny, Moscow region 141700 ; Esirkepov, Timur Zh.; Kando, Masaki; Koga, James K.; Hosokai, Tomonao; Zhidkov, Alexei G.; Japan Science and Technology Agency, CREST, 2-1, Yamadaoka, Suita, Osaka 565-0871 ; Kodama, Ryosuke; Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871

    2013-08-15

    Nonlinear axisymmetric cylindrical plasma oscillations in magnetized collisionless plasmas are a model for the electron fluid collapse on the axis behind an ultrashort relativisically intense laser pulse exciting a plasma wake wave. We present an analytical description of the strongly nonlinear oscillations showing that the magnetic field prevents closing of the cavity formed behind the laser pulse. This effect is demonstrated with 3D PIC simulations of the laser-plasma interaction. An analysis of the betatron oscillations of fast electrons in the presence of the magnetic field reveals a characteristic “Four-Ray Star” pattern.

  12. Coupled modes analysis of SRS backscattering, with Langmuir decay and possible cascadings

    E-Print Network [OSTI]

    Salcedo, Ante, 1969-

    2002-01-01

    Recent experiments aimed at understanding stimulated Raman scattering (SRS) in ICF laser-plasma interactions, suggest that SRS is coupled to the Langmuir decay interaction (LDI). The effects of LDI on the saturation of the ...

  13. A Space-Charge-Neutralizing Plasma for Beam Drift Compression

    SciTech Connect (OSTI)

    Roy, P.K.; Seidl, P.A.; Anders, A.; Bieniosek, F.M.; Coleman, J.E.; Gilson, E.P.; Greenway, W.; Grote, D.P.; Jung, J.Y.; Leitner, M.; Lidia, S.M.; Logan, B.G.; Sefkow, A.B.; Waldron, W.L.; Welch, D.R.

    2008-08-01

    Simultaneous radial focusing and longitudinal compression of intense ion beams are being studied to heat matter to the warm dense matter, or strongly coupled plasma regime. Higher compression ratios can be achieved if the beam compression takes place in a plasma-filled drift region in which the space-charge forces of the ion beam are neutralized. Recently, a system of four cathodic arc plasma sources has been fabricated and the axial plasma density has been measured. A movable plasma probe array has been developed to measure the radial and axial plasma distribution inside and outside of a {approx} 10 cm long final focus solenoid (FFS). Measured data show that the plasma forms a thin column of diameter {approx} 5 mm along the solenoid axis when the FFS is powered with an 8T field. Measured plasma density of {ge} 1 x 10{sup 13} cm{sup -3} meets the challenge of n{sub p}/Zn{sub b} > 1, where n{sub p} and n{sub b} are the plasma and ion beam density, respectively, and Z is the mean ion charge state of the plasma ions.

  14. Princeton Plasma Physics Laboratory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Plasma Physics Laboratory P.O. Box 451 Princeton, NJ 08543-0451 GPS: 100 Stellarator Road Princeton, NJ 08540 www.pppl.gov 2015 Princeton Plasma Physics Laboratory. A...

  15. Plasma window characterization

    SciTech Connect (OSTI)

    Krasik, Ya. E.; Gleizer, S.; Gurovich, V.; Kronhaus, I.; Hershcovitch, A.; Nozar, P.; Taliani, C.

    2007-03-01

    Parameters of an arc Ar plasma discharge used as a plasma window with a discharge current of {approx}50 A and a voltage of {approx}58 V are presented. It is shown that this arc discharge allows one to decrease the pressure at the low pressure end of the plasma window almost 380 times using relatively low pumping at the low pressure end of the plasma window. Calculations of the plasma parameters and their spatial distribution using a simple wall-stabilized arc model showed a satisfactory agreement with the experimentally obtained data. It is shown that a significant decrease in gas flow through the plasma window occurs due to the increase in plasma viscosity. An improvement of the plasma window ignition and some of its design aspects are described as well.

  16. Basics of Dusty Plasma

    SciTech Connect (OSTI)

    Ignatov, A.M. [Prokhorov Institute of General Physics, Russian Academy of Sciences, ul. Vavilova 38, Moscow, 119991 (Russian Federation)

    2005-01-15

    The paper presents an introductory review of the basic physical processes in dusty plasmas. The topics to be addressed are dust charging, forces acting on dust grains, interaction between dust grains, and dust-plasma structures.

  17. Segmented ceramic liner for induction furnaces

    DOE Patents [OSTI]

    Gorin, A.H.; Holcombe, C.E.

    1994-07-26

    A non-fibrous ceramic liner for induction furnaces is provided by vertically stackable ring-shaped liner segments made of ceramic material in a light-weight cellular form. The liner segments can each be fabricated as a single unit or from a plurality of arcuate segments joined together by an interlocking mechanism. Also, the liner segments can be formed of a single ceramic material or can be constructed of multiple concentric layers with the layers being of different ceramic materials and/or cellular forms. Thermomechanically damaged liner segments are selectively replaceable in the furnace. 5 figs.

  18. Segmented ceramic liner for induction furnaces

    DOE Patents [OSTI]

    Gorin, Andrew H. (Knoxville, TN); Holcombe, Cressie E. (Knoxville, TN)

    1994-01-01

    A non-fibrous ceramic liner for induction furnaces is provided by vertically stackable ring-shaped liner segments made of ceramic material in a light-weight cellular form. The liner segments can each be fabricated as a single unit or from a plurality of arcuate segments joined together by an interlocking mechanism. Also, the liner segments can be formed of a single ceramic material or can be constructed of multiple concentric layers with the layers being of different ceramic materials and/or cellular forms. Thermomechanically damaged liner segments are selectively replaceable in the furnace.

  19. Modeling of imploded annular plasmas. Annual report

    SciTech Connect (OSTI)

    Terry, R.E.; Guillory, J.U.

    1981-05-01

    This report treats three areas of advance during the 1980 effort: (I) improvements to the 1-D strongly-coupled plasma implosion and radiation code SPLAT and results of radiative yield studies using the code; (II) development of formalism for solving the field penetration/skin-depth problem in an inhomogeneous, time-varying imploding conductor in a plasma-loaded diode; (III) circuit equation and scaling of hard radiation in the presence of fully developed sausage instability (beading) of the assembled plasma. In addition, a short section (Chapter V) is devoted to work in progress: high-accuracy matrix inversion techniques and interpolators for solving the generalized Hertz vector equations used in II above, and for following CRE equations and diffusive behavior in general; and, beginning plans for modifying 1-D MHD codes, making them compatible with the field-diffusion and corona programs and with CRE radiation packages.

  20. Lithium Surface Coatings for Improved Plasma Performance in NSTX

    SciTech Connect (OSTI)

    Kugel, H W; Ahn, J -W; Allain, J P; Bell, R; Boedo, J; Bush, C; Gates, D; Gray, T; Kaye, S; Kaita, R; LeBlanc, B; Maingi, R; Majeski, R; Mansfield, D; Menard, J; Mueller, D; Ono, M; Paul, S; Raman, R; Roquemore, A L; Ross, P W; Sabbagh, S; Schneider, H; Skinner, C H; Soukhanovskii, V; Stevenson, T; Timberlake, J; Wampler, W R

    2008-02-19

    NSTX high-power divertor plasma experiments have shown, for the first time, significant and frequent benefits from lithium coatings applied to plasma facing components. Lithium pellet injection on NSTX introduced lithium pellets with masses 1 to 5 mg via He discharges. Lithium coatings have also been applied with an oven that directed a collimated stream of lithium vapor toward the graphite tiles of the lower center stack and divertor. Lithium depositions from a few mg to 1 g have been applied between discharges. Benefits from the lithium coating were sometimes, but not always seen. These improvements sometimes included decreases plasma density, inductive flux consumption, and ELM frequency, and increases in electron temperature, ion temperature, energy confinement and periods of MHD quiescence. In addition, reductions in lower divertor D, C, and O luminosity were measured.

  1. Thermal distributions in stellar plasmas, nuclear reactions and solar neutrinos

    E-Print Network [OSTI]

    M. Coraddu; G. Kaniadakis; A. Lavagno; M. Lissia; G. Mezzorani; P. Quarati

    1998-11-24

    The physics of nuclear reactions in stellar plasma is reviewed with special emphasis on the importance of the velocity distribution of ions. Then the properties (density and temperature) of the weak-coupled solar plasma are analysed, showing that the ion velocities should deviate from the Maxwellian distribution and could be better described by a weakly-nonexstensive (|q-1|solar neutrino fluxes, and on the pp neutrino energy spectrum, and analyse the consequences for the solar neutrino problem.

  2. A simple model for induction core voltage distributions

    E-Print Network [OSTI]

    Briggs, Richard J.; Fawley, William M.

    2004-01-01

    3 Electric fields around Metglas-mylar interface where •-,gaps between the four Metglas induction cores is veryare composed of 4"-wide Metglas tapewith anorrinal thickness

  3. Felix Bloch, Nuclear Induction, Bloch Equations, Bloch Theorem...

    Office of Scientific and Technical Information (OSTI)

    Felix Bloch, Nuclear Induction, and Bloch Equations Resources with Additional Information Stressing "the importance both of demonstrating the neutron's magnetic moment and of...

  4. Seismic baseline and induction studies- Roosevelt Hot Springs...

    Open Energy Info (EERE)

    Seismic baseline and induction studies- Roosevelt Hot Springs, Utah and Raft River, Idaho Jump to: navigation, search OpenEI Reference LibraryAdd to library Report: Seismic...

  5. Mirror plasma apparatus

    DOE Patents [OSTI]

    Moir, Ralph W. (Livermore, CA)

    1981-01-01

    A mirror plasma apparatus which utilizes shielding by arc discharge to form a blanket plasma and lithium walls to reduce neutron damage to the wall of the apparatus. An embodiment involves a rotating liquid lithium blanket for a tandem mirror plasma apparatus wherein the first wall of the central mirror cell is made of liquid lithium which is spun with angular velocity great enough to keep the liquid lithium against the first material wall, a blanket plasma preventing the lithium vapor from contaminating the plasma.

  6. Verification and validation for induction heating

    SciTech Connect (OSTI)

    Lam, Kin [Los Alamos National Laboratory; Tippetts, Trevor B [Los Alamos National Laboratory; Allen, David W [NON LANL

    2008-01-01

    Truchas is a software package being developed at LANL within the Telluride project for predicting the complex physical processes in metal alloy casting. The software was designed to be massively parallel, multi-material, multi-physics, and to run on 3D, fully unstructured meshes. This work describes a Verification and Validation assessment of Truchas for simulating the induction heating phase of a casting process. We used existing data from a simple experiment involving the induction heating of a graphite cylinder, as graphite is a common material used for mold assemblies. Because we do not have complete knowledge of all the conditions and properties in this experiment (as is the case in many other experiments), we performed a parameter sensitivity study, modeled the uncertainties of the most sensitive parameters, and quantified how these uncertainties propagate to the Truchas output response. A verification analysis produced estimates of the numerical error of the Truchas solution to our computational model. The outputs from Truchas runs with randomly sampled parameter values were used for the validation study.

  7. A HIGH REPETITION PLASMA MIRROR FOR STAGED ELECTRON ACCELERATION

    SciTech Connect (OSTI)

    Sokollik, Thomas; Shiraishi, Satomi; Osterhoff, Jens; Evans, Eugene; Gonsalves, Anthony; Nakamura, Kei; vanTilborg, Jeroen; Lin, Chen; Toth, Csaba; Leemans, Wim

    2011-07-22

    In order to build a compact, staged laser plasma accelerator the in-coupling of the laser beam to the different stages represents one of the key issues. To limit the spatial foot print and thus to realize a high overall acceleration gradient, a concept has to be found which realizes this in-coupling within a few centimeters. We present experiments on a tape-drive based plasma mirror which could be used to reflect the focused laser beam into the acceleration stage.

  8. Arc Plasma Torch Modeling

    E-Print Network [OSTI]

    Trelles, J P; Vardelle, A; Heberlein, J V R

    2013-01-01

    Arc plasma torches are the primary components of various industrial thermal plasma processes involving plasma spraying, metal cutting and welding, thermal plasma CVD, metal melting and remelting, waste treatment and gas production. They are relatively simple devices whose operation implies intricate thermal, chemical, electrical, and fluid dynamics phenomena. Modeling may be used as a means to better understand the physical processes involved in their operation. This paper presents an overview of the main aspects involved in the modeling of DC arc plasma torches: the mathematical models including thermodynamic and chemical non-equilibrium models, turbulent and radiative transport, thermodynamic and transport property calculation, boundary conditions and arc reattachment models. It focuses on the conventional plasma torches used for plasma spraying that include a hot-cathode and a nozzle anode.

  9. Global model of a gridded-ion thruster powered by a radiofrequency inductive coil

    SciTech Connect (OSTI)

    Chabert, P.; Arancibia Monreal, J.; Bredin, J.; Popelier, L.; Aanesland, A. [LPP, CNRS, Ecole Polytechnique, UPMC, Paris XI, 91128 Palaiseau (France)

    2012-07-15

    A global (volume-averaged) model of a gridded-ion thruster is proposed. The neutral propellant (xenon gas) is injected into the thruster chamber at a fixed rate and a plasma is generated by circulating a radiofrequency current in an inductive coil. The ions generated in this plasma are accelerated out of the thruster by a pair of DC biased grids. The neutralization downstream is not treated. Xenon atoms also flow out of the thruster across the grids. The model, based on particle and energy balance equations, solves for four global variables in the thruster chamber: the plasma density, the electron temperature, the neutral gas (atom) density, and the neutral gas temperature. The important quantities to evaluate the thruster efficiency and performances are calculated from these variables and from the voltage across the grids. It is found that the mass utilization efficiency rapidly decreases with the gas flow rate. However, the radiofrequency power transfer efficiency increases significantly with the injected gas flow rate. Therefore, there is a compromise to be found between these two quantities.

  10. Acoustic stabilization of electric arc instabilities in nontransferred plasma torches

    SciTech Connect (OSTI)

    Rat, V.; Coudert, J. F.

    2010-03-08

    Electric arc instabilities in dc plasma torches lead to nonhomogeneous treatments of nanosized solid particles or liquids injected within thermal plasma jets. This paper shows that an additional acoustic resonator mounted on the cathode cavity allows reaching a significant damping of these instabilities, particularly the Helmholtz mode of arc oscillations. The acoustic resonator is coupled with the Helmholtz resonator of the plasma torch limiting the amplitude of arc voltage variations. It is also highlighted that this damping is dependent on friction effects in the acoustic resonator.

  11. Study of surface kinetics in PECVD chamber cleaning using remote plasma source

    E-Print Network [OSTI]

    An, Ju Jin

    2008-01-01

    The scope of this research work is to characterize the Transformer Coupled Toroidal Plasma (TCTP); to understand gas phase reactions and surface reactions of neutrals in the cleaning chamber by analyzing the concentration ...

  12. Antenna coupled Kinetic Inductance Detectors camera design and performance at IRAM 30m telescope

    E-Print Network [OSTI]

    Leclercq, Samuel

    = 80.000 matched to expected sky load · Qi decreases with power loading · S21,min =Q/Qi Dark;Grenoble NIKA, 31 Aug 2010 9 · Sky loading simulated by temperature increase in dark environment · NEP noise to calculate individual pixel gain #12;Grenoble NIKA, 31 Aug 2010 14 NET of the system from Mars

  13. Modal S-matrix method for the optimum design of inductively direct-coupled

    E-Print Network [OSTI]

    Bornemann, Jens

    . Arndt, Dr.-Ing., Sen.Mem.I.E.E.E., J. Bornemann, Dr.-Ing., D. Heckmann, Dipl.-lng., C. Piontek, Dipl.-lng., H. Semmerow, Dipl.-lng., and H. Schueler, Dipl.-lng. Indexing terms: Computer-aided design

  14. Inductively Coupled Circuits with Spin Wave Bus for Information Processing A. Khitun, 1)

    E-Print Network [OSTI]

    Roshchin, Igor V.

    Architectonics (FENA), University of California at Los Angeles, Los Angeles, California, 90095-1594 2) Stanford, Stanford University, Stanford, California, 94305- 4045 3) Physics Department, University of California, San transmission is accomplished without electron transport. Besides, there are other significant advantages: (i

  15. Two-dimensional double layer in plasma in a diverging magnetic field

    SciTech Connect (OSTI)

    Saha, S. K.; Raychaudhuri, S.; Chowdhury, S.; Janaki, M. S.; Hui, A. K.

    2012-09-15

    Plasma created by an inductive RF discharge is allowed to expand along a diverging magnetic field. Measurement of the axial plasma potential profile reveals the formation of an electric double layer near the throat of the expansion chamber. An accelerated ion beam has been detected in the downstream region, confirming the presence of the double layer. The 2-D nature of the ion energy distribution function of the downstream plasma has been studied by a movable ion energy analyser, which shows that the beam radius increases along the axial distance. The 2-D structure of the plasma potential has been studied by a movable emissive probe. The existence of a secondary lobe in the contour plot of plasma equipotential is a new observation. It is also an interesting observation that the most diverging magnetic field line not intercepting the junction of the discharge tube and the expansion chamber has an electric field aligned with it.

  16. Collective plasma effects in scattering of radiation in astrophysical plasmas (Collective plasma processes and the solar neutrino problem)

    E-Print Network [OSTI]

    Tsytovich, V N; De Angelis, U; Forlani, A

    1995-01-01

    Collective plasma effects in scattering of radiation in astrophysical plasmas (Collective plasma processes and the solar neutrino problem)

  17. Three tooth kinematic coupling

    DOE Patents [OSTI]

    Hale, Layton C. (Livermore, CA)

    2000-01-01

    A three tooth kinematic coupling based on having three theoretical line contacts formed by mating teeth rather than six theoretical point contacts. The geometry requires one coupling half to have curved teeth and the other coupling half to have flat teeth. Each coupling half has a relieved center portion which does not effect the kinematics, but in the limit as the face width approaches zero, three line contacts become six point contacts. As a result of having line contact, a three tooth coupling has greater load capacity and stiffness. The kinematic coupling has application for use in precision fixturing for tools or workpieces, and as a registration device for a work or tool changer or for optics in various products.

  18. Plasma Camp | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Plasma Camp December 12, 2013 Due to unforeseen budget cuts, this program has been cancelled for 2014. We are very sorry we cannot offer the program and apologize for the late...

  19. Mixed Inductive/Coinductive Types and Strong Normalization

    E-Print Network [OSTI]

    Abel, Andreas

    and coinductive types. Most research on inductive types has focused on the iso-style, i. e., there are explicit programming language. Research partially supported by the EU coordination action TYPES (510996). #12;InMixed Inductive/Coinductive Types and Strong Normalization Andreas Abel Department of Computer

  20. Personality and Social Context: Impact on Emotion Induction from Movies

    E-Print Network [OSTI]

    Widmer, Gerhard

    Personality and Social Context: Impact on Emotion Induction from Movies Ante Odi´c1 , Marko Tkalcic were still interested in the impact of the social context on the emotion induction. If the social. In this paper we describe our preliminary work on under- standing the impact of personality on the emotion

  1. Induction slag reduction process for purifying metals

    DOE Patents [OSTI]

    Traut, Davis E. (Corvallis, OR); Fisher, II, George T. (Albany, OR); Hansen, Dennis A. (Corvallis, OR)

    1991-01-01

    A continuous method is provided for purifying and recovering transition metals such as neodymium and zirconium that become reactive at temperatures above about 500.degree. C. that comprises the steps of contacting the metal ore with an appropriate fluorinating agent such as an alkaline earth metal fluosilicate to form a fluometallic compound, and reducing the fluometallic compound with a suitable alkaline earth or alkali metal compound under molten conditions, such as provided in an induction slag metal furnace. The method of the invention is advantageous in that it is simpler and less expensive than methods used previously to recover pure metals, and it may be employed with a wide range of transition metals that were reactive with enclosures used in the prior art methods and were hard to obtain in uncontaminated form.

  2. Screening length in plasma winds

    E-Print Network [OSTI]

    Elena Caceres; Makoto Natsuume; Takashi Okamura

    2007-06-04

    We study the screening length L_s of a heavy quark-antiquark pair in strongly coupled gauge theory plasmas flowing at velocity v. Using the AdS/CFT correspondence we investigate, analytically, the screening length in the ultra-relativistic limit. We develop a procedure that allows us to find the scaling exponent for a large class of backgrounds. We find that for conformal theories the screening length is (boosted energy density)^{-1/d}. As examples of conformal backgrounds we study R-charged black holes and Schwarzschild-anti-deSitter black holes in (d+1)-dimensions. For non-conformal theories, we find that the exponent deviates from -1/d and as examples we study the non-extremal Klebanov-Tseytlin and Dp-brane geometries. We find an interesting relation between the deviation of the scaling exponent from the conformal value and the speed of sound.

  3. System and method for generating steady state confining current for a toroidal plasma fusion reactor

    DOE Patents [OSTI]

    Fisch, Nathaniel J. (Cambridge, MA)

    1981-01-01

    A system for generating steady state confining current for a toroidal plasma fusion reactor providing steady-state generation of the thermonuclear power. A dense, hot toroidal plasma is initially prepared with a confining magnetic field with toroidal and poloidal components. Continuous wave RF energy is injected into said plasma to establish a spectrum of traveling waves in the plasma, where the traveling waves have momentum components substantially either all parallel, or all anti-parallel to the confining magnetic field. The injected RF energy is phased to couple to said traveling waves with both a phase velocity component and a wave momentum component in the direction of the plasma traveling wave components. The injected RF energy has a predetermined spectrum selected so that said traveling waves couple to plasma electrons having velocities in a predetermined range .DELTA.. The velocities in the range are substantially greater than the thermal electron velocity of the plasma. In addition, the range is sufficiently broad to produce a raised plateau having width .DELTA. in the plasma electron velocity distribution so that the plateau electrons provide steady-state current to generate a poloidal magnetic field component sufficient for confining the plasma. In steady state operation of the fusion reactor, the fusion power density in the plasma exceeds the power dissipated in the plasma.

  4. System and method for generating steady state confining current for a toroidal plasma fusion reactor

    DOE Patents [OSTI]

    Bers, Abraham (Arlington, MA)

    1981-01-01

    A system for generating steady state confining current for a toroidal plasma fusion reactor providing steady-state generation of the thermonuclear power. A dense, hot toroidal plasma is initially prepared with a confining magnetic field with toroidal and poloidal components. Continuous wave RF energy is injected into said plasma to estalish a spectrum of traveling waves in the plasma, where the traveling waves have momentum components substantially either all parallel, or all anti-parallel to the confining magnetic field. The injected RF energy is phased to couple to said traveling waves with both a phase velocity component and a wave momentum component in the direction of the plasma traveling wave components. The injected RF energy has a predetermined spectrum selected so that said traveling waves couple to plasma electrons having velocities in a predetermined range .DELTA.. The velocities in the range are substantially greater than the thermal electron velocity of the plasma. In addition, the range is sufficiently broad to produce a raised plateau having width .DELTA. in the plasma electron velocity distribution so that the plateau electrons provide steady-state current to generate a poloidal magnetic field component sufficient for confining the plasma. In steady state operation of the fusion reactor, the fusion power density in the plasma exceeds the power dissipated inthe plasma.

  5. Fusion and Plasma Physics are at the Core of Nature's Most Intriguing Self-Driven Systems

    E-Print Network [OSTI]

    University Presented at Columbia University Plasma Physics Colloquium in the City of New York http for a Major Next Step Magnetic Fusion Experiment Explore and understand the strong non-linear couplingFusion and Plasma Physics are at the Core of Nature's Most Intriguing Self-Driven Systems CHANDRA

  6. Vacuum Induction Melting Unit Induction heating is a process wherein induced eddy currents heat conductive materials. This heating

    E-Print Network [OSTI]

    Subramaniam, Anandh

    Vacuum Induction Melting Unit Induction heating is a process wherein induced eddy currents heat can be melted at a time. There are three main parts to the system: chiller, power unit and vacuum unit. The vacuum unit with rotary and diffusion pumps can attain a vacuum of 106 m bar. The power can deliver

  7. Translation-coupling systems

    DOE Patents [OSTI]

    Pfleger, Brian; Mendez-Perez, Daniel

    2013-11-05

    Disclosed are systems and methods for coupling translation of a target gene to a detectable response gene. A version of the invention includes a translation-coupling cassette. The translation-coupling cassette includes a target gene, a response gene, a response-gene translation control element, and a secondary structure-forming sequence that reversibly forms a secondary structure masking the response-gene translation control element. Masking of the response-gene translation control element inhibits translation of the response gene. Full translation of the target gene results in unfolding of the secondary structure and consequent translation of the response gene. Translation of the target gene is determined by detecting presence of the response-gene protein product. The invention further includes RNA transcripts of the translation-coupling cassettes, vectors comprising the translation-coupling cassettes, hosts comprising the translation-coupling cassettes, methods of using the translation-coupling cassettes, and gene products produced with the translation-coupling cassettes.

  8. Earth coupled cooling techniques

    SciTech Connect (OSTI)

    Grondzik, W.T.; Boyer, L.L.; Johnston, T.L.

    1981-01-01

    Earth coupled cooling is an important consideration for residential and commercial designers, owners, and builders in many regions of the country. The potential benefits which can be expected from passive earth contact cooling are reviewed. Recommendations for the design of earth sheltered structures incorporating earth coupled cooling strategies are also presented.

  9. Plasma Processing Of Hydrocarbon

    SciTech Connect (OSTI)

    Grandy, Jon D; Peter C. Kong; Brent A. Detering; Larry D. Zuck

    2007-05-01

    The Idaho National Laboratory (INL) developed several patented plasma technologies for hydrocarbon processing. The INL patents include nonthermal and thermal plasma technologies for direct natural gas to liquid conversion, upgrading low value heavy oil to synthetic light crude, and to convert refinery bottom heavy streams directly to transportation fuel products. Proof of concepts has been demonstrated with bench scale plasma processes and systems to convert heavy and light hydrocarbons to higher market value products. This paper provides an overview of three selected INL patented plasma technologies for hydrocarbon conversion or upgrade.

  10. Tritium Plasma Experiment and

    Office of Environmental Management (EM)

    23-25, 2014 2 Safety concern: "in-vessel inventory source term" * Challenges in neutron-irradiated plasma facing components (PFCs) - Radiation damages (vacancy,...

  11. Princeton Plasma Physics Laboratory

    SciTech Connect (OSTI)

    Not Available

    1990-01-01

    This report discusses the following topics: principal parameters achieved in experimental devices fiscal year 1990; tokamak fusion test reactor; compact ignition tokamak; Princeton beta experiment- modification; current drive experiment-upgrade; international collaboration; x-ray laser studies; spacecraft glow experiment; plasma processing: deposition and etching of thin films; theoretical studies; tokamak modeling; international thermonuclear experimental reactor; engineering department; project planning and safety office; quality assurance and reliability; technology transfer; administrative operations; PPPL patent invention disclosures for fiscal year 1990; graduate education; plasma physics; graduate education: plasma science and technology; science education program; and Princeton Plasma Physics Laboratory reports fiscal year 1990.

  12. The model coupling toolkit.

    SciTech Connect (OSTI)

    Larson, J. W.; Jacob, R. L.; Foster, I.; Guo, J.

    2001-04-13

    The advent of coupled earth system models has raised an important question in parallel computing: What is the most effective method for coupling many parallel models to form a high-performance coupled modeling system? We present our solution to this problem--The Model Coupling Toolkit (MCT). We explain how our effort to construct the Next-Generation Coupler for NCAR Community Climate System Model motivated us to create this toolkit. We describe in detail the conceptual design of the MCT and explain its usage in constructing parallel coupled models. We present preliminary performance results for the toolkit's parallel data transfer facilities. Finally, we outline an agenda for future development of the MCT.

  13. Non-Equilibrium Vibrational Kinetics in Radiofrequency H2 Plasmas: a Comparison Between Theoretical and Experimental Results

    SciTech Connect (OSTI)

    Capitelli, M.; De Pascale, O.; Shakatov, V.; Hassouni, K.; Lombardi, G.; Gicquel, A.

    2005-05-16

    Vibrational and rotational experimental temperatures of molecular hydrogen obtained by Coherent Anti-Stokes Spectroscopy (CARS) in Radiofrequency Inductive Plasmas have been analyzed and interpreted in terms of vibration, electron, dissociation-recombination and attachment kinetics. The analysis clarifies the role of atomic hydrogen and its heterogeneous recombination in affecting the vibrational content of the molecules.

  14. ICP Plasma Jet For Target Interaction Studies Of O-atoms In O2 And CO2 Supersonic Flows

    SciTech Connect (OSTI)

    Dilecce, G.; Ambrico, P.F.; De Benedictis, S. [Istituto di Metodologie Inorganiche e dei Plasmai, CNR-sez. Ter. Bari, c/o Dipartimento di Chimica, Universita di Bari- Via Orabona 4, 7126 Bari (Italy)

    2005-05-16

    An RF plasma jet using a planar inductive discharge in CO2 or in O2 gases has been used to produce a supersonic flow of O atoms suitable for gas-surface interaction experiments. The supersonic O atom stream is characterized by 2D space resolved TALIF.

  15. Multi-sensor Wireless System for Fault Detection in Induction Motors

    E-Print Network [OSTI]

    Tarkesh Esfahani, Ehsan

    2012-01-01

    2 Faults in Motors 2.1 Bearing Faultcombined faults in induction motors,” IEEE Transactions onV. Climente-Alarcon, “Induction motor diagnosis based on a

  16. Health Monitoring of Drive Connected Three-Phase Induction Motors ----- From Wired Towards Wireless Sensor Networks

    E-Print Network [OSTI]

    Xue, Xin

    2009-01-01

    bars in operating induction motors," Energy Conversion, IEEEbe set up between several motors in a large facility. Multi-for in-service induction motors," Industry Applications,

  17. Radio frequency plasma power dependence of the moisture permeation barrier characteristics of Al{sub 2}O{sub 3} films deposited by remote plasma atomic layer deposition

    SciTech Connect (OSTI)

    Jung, Hyunsoo [Division of Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of) [Division of Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Samsung Display Co. Ltd., Tangjeong, Chungcheongnam-Do 336-741 (Korea, Republic of); Choi, Hagyoung; Lee, Sanghun [Division of Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of)] [Division of Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Jeon, Heeyoung [Department of Nano-scale Semiconductor Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of)] [Department of Nano-scale Semiconductor Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Jeon, Hyeongtag [Division of Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of) [Division of Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Department of Nano-scale Semiconductor Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of)

    2013-11-07

    In the present study, we investigated the gas and moisture permeation barrier properties of Al{sub 2}O{sub 3} films deposited on polyethersulfone films (PES) by capacitively coupled plasma (CCP) type Remote Plasma Atomic Layer Deposition (RPALD) at Radio Frequency (RF) plasma powers ranging from 100 W to 400 W in 100 W increments using Trimethylaluminum [TMA, Al(CH{sub 3}){sub 3}] as the Al source and O{sub 2} plasma as the reactant. To study the gas and moisture permeation barrier properties of 100-nm-thick Al{sub 2}O{sub 3} at various plasma powers, the Water Vapor Transmission Rate (WVTR) was measured using an electrical Ca degradation test. WVTR decreased as plasma power increased with WVTR values for 400 W and 100 W of 2.6 × 10{sup ?4} gm{sup ?2}day{sup ?1} and 1.2 × 10{sup ?3} gm{sup ?2}day{sup ?1}, respectively. The trends for life time, Al-O and O-H bond, density, and stoichiometry were similar to that of WVTR with improvement associated with increasing plasma power. Further, among plasma power ranging from 100 W to 400 W, the highest power of 400 W resulted in the best moisture permeation barrier properties. This result was attributed to differences in volume and amount of ion and radical fluxes, to join the ALD process, generated by O{sub 2} plasma as the plasma power changed during ALD process, which was determined using a plasma diagnosis technique called the Floating Harmonic Method (FHM). Plasma diagnosis by FHM revealed an increase in ion flux with increasing plasma power. With respect to the ALD process, our results indicated that higher plasma power generated increased ion and radical flux compared with lower plasma power. Thus, a higher plasma power provides the best gas and moisture permeation barrier properties.

  18. Tungsten dust impact on ITER-like plasma edge

    SciTech Connect (OSTI)

    Smirnov, R. D. Krasheninnikov, S. I.; Pigarov, A. Yu.; Rognlien, T. D.

    2015-01-15

    The impact of tungsten dust originating from divertor plates on the performance of edge plasma in ITER-like discharge is evaluated using computer modeling with the coupled dust-plasma transport code DUSTT-UEDGE. Different dust injection parameters, including dust size and mass injection rates, are surveyed. It is found that tungsten dust injection with rates as low as a few mg/s can lead to dangerously high tungsten impurity concentrations in the plasma core. Dust injections with rates of a few tens of mg/s are shown to have a significant effect on edge plasma parameters and dynamics in ITER scale tokamaks. The large impact of certain phenomena, such as dust shielding by an ablation cloud and the thermal force on tungsten ions, on dust/impurity transport in edge plasma and consequently on core tungsten contamination level is demonstrated. It is also found that high-Z impurities provided by dust can induce macroscopic self-sustained plasma oscillations in plasma edge leading to large temporal variations of edge plasma parameters and heat load to divertor target plates.

  19. Nonlinear dynamics of large amplitude modes in a magnetized plasma

    SciTech Connect (OSTI)

    Brodin, G.; Stenflo, L.

    2014-12-15

    We derive two equations describing the coupling between electromagnetic and electrostatic oscillations in one-dimensional geometry in a magnetized cold and non-relativistic plasma. The nonlinear interaction between the wave modes is studied numerically. The effects of the external magnetic field strength and the initial electromagnetic polarization are of particular interest here. New results can, thus, be identified.

  20. Scaled Synthesis of Boron Nitride Nanotubes, Nanoribbons, and Nanococoons Using Direct Feedstock Injection into an Extended-

    E-Print Network [OSTI]

    Zettl, Alex

    lack of availability of the synthesized materials. The original arc-plasma synthesis method of BNNTs Injection into an Extended- Pressure, Inductively-Coupled Thermal Plasma Aidin Fathalizadeh,, Thang Pham: A variable pressure (up to 10 atm) powder/gas/ liquid injection inductively coupled plasma system has been

  1. Weakly Ionized Plasmas in Hypersonics: Fundamental Kinetics and Flight Applications

    SciTech Connect (OSTI)

    Macheret, Sergey

    2005-05-16

    The paper reviews some of the recent studies of applications of weakly ionized plasmas to supersonic/hypersonic flight. Plasmas can be used simply as means of delivering energy (heating) to the flow, and also for electromagnetic flow control and magnetohydrodynamic (MHD) power generation. Plasma and MHD control can be especially effective in transient off-design flight regimes. In cold air flow, nonequilibrium plasmas must be created, and the ionization power budget determines design, performance envelope, and the very practicality of plasma/MHD devices. The minimum power budget is provided by electron beams and repetitive high-voltage nanosecond pulses, and the paper describes theoretical and computational modeling of plasmas created by the beams and repetitive pulses. The models include coupled equations for non-local and unsteady electron energy distribution function (modeled in forward-back approximation), plasma kinetics, and electric field. Recent experimental studies at Princeton University have successfully demonstrated stable diffuse plasmas sustained by repetitive nanosecond pulses in supersonic air flow, and for the first time have demonstrated the existence of MHD effects in such plasmas. Cold-air hypersonic MHD devices are shown to permit optimization of scramjet inlets at Mach numbers higher than the design value, while operating in self-powered regime. Plasma energy addition upstream of the inlet throat can increase the thrust by capturing more air (Virtual Cowl), or it can reduce the flow Mach number and thus eliminate the need for an isolator duct. In the latter two cases, the power that needs to be supplied to the plasma would be generated by an MHD generator downstream of the combustor, thus forming the 'reverse energy bypass' scheme. MHD power generation on board reentry vehicles is also discussed.

  2. Plasma technology directory

    SciTech Connect (OSTI)

    Ward, P.P.; Dybwad, G.L.

    1995-03-01

    The Plasma Technology Directory has two main goals: (1) promote, coordinate, and share plasma technology experience and equipment within the Department of Energy; and (2) facilitate technology transfer to the commercial sector where appropriate. Personnel are averaged first by Laboratory and next by technology area. The technology areas are accelerators, cleaning and etching deposition, diagnostics, and modeling.

  3. Triggered plasma opening switch

    DOE Patents [OSTI]

    Mendel, Clifford W. (Albuquerque, NM)

    1988-01-01

    A triggerable opening switch for a very high voltage and current pulse includes a transmission line extending from a source to a load and having an intermediate switch section including a plasma for conducting electrons between transmission line conductors and a magnetic field for breaking the plasma conduction path and magnetically insulating the electrons when it is desired to open the switch.

  4. Diamagnetism of rotating plasma

    SciTech Connect (OSTI)

    Young, W. C.; Hassam, A. B.; Romero-Talamas, C. A.; Ellis, R. F.; Teodorescu, C. [IREAP, University of Maryland, College Park, Maryland 20742 (United States)

    2011-11-15

    Diamagnetism and magnetic measurements of a supersonically rotating plasma in a shaped magnetic field demonstrate confinement of plasma pressure along the magnetic field resulting from centrifugal force. The Grad-Shafranov equation of ideal magnetohydrodynamic force balance, including supersonic rotation, is solved to confirm that the predicted angular velocity is in agreement with spectroscopic measurements of the Doppler shifts.

  5. Plasma opening switch

    DOE Patents [OSTI]

    Savage, Mark E. (Albuquerque, NM); Mendel, Jr., Clifford W. (Albuquerque, NM)

    2001-01-01

    A command triggered plasma opening switch assembly using an amplification stage. The assembly surrounds a coaxial transmission line and has a main plasma opening switch (POS) close to the load and a trigger POS upstream from the main POS. The trigger POS establishes two different current pathways through the assembly depended on whether it has received a trigger current pulse. The initial pathway has both POS's with plasma between their anodes and cathodes to form a short across the transmission line and isolating the load. The final current pathway is formed when the trigger POS receives a trigger current pulse which energizes its fast coil to push the conductive plasma out from between its anode and cathode, allowing the main transmission line current to pass to the fast coil of the main POS, thus pushing its plasma out the way so as to establish a direct current pathway to the load.

  6. Research | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Overview Experimental Fusion Research Theoretical Fusion Research Basic Plasma Science Plasma Astrophysics Other Physics and Engineering Research PPPL Technical Reports NSTX-U...

  7. Disformally coupled inflation

    E-Print Network [OSTI]

    van de Bruck, Carsten; Longden, Chris

    2015-01-01

    A disformal coupling between two scalar fields is considered in the context of cosmological inflation. The coupling introduces novel derivative interactions mixing the kinetic terms of the fields but without introducing superluminal or unstable propagation of the two scalar fluctuation modes. Though the typical effect of the disformal coupling is to inhibit one of the fields from inflating the universe, the energy density of the other field can drive viable near Sitter -inflation in the presence of nontrivial disformal dynamics, in particular when one assumes exponential instead of power-law form for the couplings. The linear perturbation equations are written for the two-field system, its canonical degrees of freedom are quantised, their spectra are derived and the inflationary predictions are reported for numerically solved exponential models. A generic prediction is low tensor-to-scalar ratio.

  8. Coupling in the Tevatron

    SciTech Connect (OSTI)

    Gelfand, N.M.

    1994-12-01

    The performance of the Fermilab Tevatron Collider at the commencement of run Ib was far below expectations. After a frustrating period of several months, a low-{beta} quad downstream of the interaction point at B0 was found to be rolled. This rolled quadrupole coupled the horizontal and vertical motion of the Tevatron beams. It also made matching the beam from the Main Ring to the Tevatron impossible, resulting in emittance blow up on injection. The net result of the roll was a significant reduction in the Tevatron luminosity. When the roll in the quadrupole was corrected the performance of the Tevatron improved dramatically. This note will discuss the experimental data indicating the presence of coupling and subsequent calculations which show how coupling an affect the luminosity. It is not intended to exhaust a discussion of coupling, which hopefully will be understood well enough to be discussed in a subsequent note.

  9. Negative-coupling resonances in pump-coupled lasers

    E-Print Network [OSTI]

    T. W. Carr; M. L. Taylor; I. B. Schwartz

    2005-10-28

    We consider coupled lasers, where the intensity deviations from the steady state, modulate the pump of the other lasers. Most of our results are for two lasers where the coupling constants are of opposite sign. This leads to a Hopf bifurcation to periodic output for weak coupling. As the magnitude of the coupling constants is increased (negatively) we observe novel amplitude effects such as a weak coupling resonance peak and, strong coupling subharmonic resonances and chaos. In the weak coupling regime the output is predicted by a set of slow evolution amplitude equations. Pulsating solutions in the strong coupling limit are described by discrete map derived from the original model.

  10. Boundary Plasma Issues in Burning Plasma Science

    E-Print Network [OSTI]

    Pitcher, C. S.

    impurity production 4. screening of impurities · why a burning plasma experiment? · BP contribution impurity production, high Zeff (not desirable mode of operation ) #12;···· we know a lot more now than helium ash - induce SOL flow towards divertor - control density · helium exhaust time, i.e. He , limited

  11. Boundary Plasma Issues in Burning Plasma Science

    E-Print Network [OSTI]

    impurity production 4. screening of impurities 5. burning plasma experiment? #12;(1) Wide Dispersal points are swept (BPX), but Tt will be high impurity production, high Zeff (not desirable mode- modes (tight baffling??) · allows efficient pumping to: - remove helium ash - induce SOL flow towards

  12. Boundary Plasma Issues in Burning Plasma Science

    E-Print Network [OSTI]

    Pitcher, C. S.

    impurity production 4. screening of impurities 5. burning plasma experiment? #12;(1) Wide Dispersal if strike points are swept (BPX), but Tt will be high impurity production, high Zeff (not desirable mode pressure for H- modes (tight baffling??) · allows efficient pumping to: - remove helium ash - induce SOL

  13. Synchronous Machine Modeling Notes2 1.0 Inductances

    E-Print Network [OSTI]

    McCalley, James D.

    Synchronous Machine Modeling ­ Notes2 1.0 Inductances Recall the relation between flux linkages. Rather, for each coil and coil pair in the synchronous machine, we are going to see if any of the terms

  14. Induction effects for heterochromatic brightness matching, heterochromatic flicker photometry,

    E-Print Network [OSTI]

    Dobkins, Karen R.

    Induction effects for heterochromatic brightness matching, heterochromatic flicker photometry flicker photometry (HFP), and minimally distinct border (MDB). For HBM, subjects varied the relative compared with those obtained on two other tasks: hetero- chromatic flicker photometry (HFP) and minimally

  15. Induction, Domains, Calculi: Strachey's Contributions to ProgrammingLanguage

    E-Print Network [OSTI]

    Schmidt, David A.

    Induction, Domains, Calculi: Strachey's Contributions to Programming­Language Engineering David A pioneered the analysis of programming languages in terms of semantic features. Three of Strachey programming languages designed by programming­language experts? Sometimes they are, but the requirements

  16. Development of magnetic induction machines for micro turbo machinery

    E-Print Network [OSTI]

    KöÅŸ er, Hür, 1976-

    2002-01-01

    This thesis presents the nonlinear analysis, design, fabrication, and testing of an axial-gap magnetic induction micro machine, which is a two-phase planar motor in which the rotor is suspended above the stator via mechanical ...

  17. An economical single to three phase converter for induction motors 

    E-Print Network [OSTI]

    Di Zerega, Philp Van Uytandaele

    1994-01-01

    There are several different types of single to three phase converters for induction motors available today. However, many of the presently available phase converters suffer from disadvantages such as high cost or low performance. An economical...

  18. A microfabricated ElectroQuasiStatic induction turbine-generator

    E-Print Network [OSTI]

    Steyn, J. Lodewyk (Jasper Lodewyk), 1976-

    2005-01-01

    An ElectroQuasiStatic (EQS) induction machine has been fabricated and has generated net electric power. A maximum power output of 192 [mu]W at 235 krpm has been measured under driven excitation of the six phases. Self ...

  19. Induction Consolidation/Molding of Thermoplastic Composites Using Smart Susceptors

    SciTech Connect (OSTI)

    None

    2009-02-01

    This factsheet describes a research project whose objective is to explore and define the technical and economic viability of induction consolidation for thermoplastic composites and to fabricate a wide spectrum of components in an energy-efficient manner.

  20. High School Science Teacher Induction in Texas: Implications for Policy 

    E-Print Network [OSTI]

    Ivey, Toni Ann

    2011-02-22

    . Induction Programs A Nation at Risk (National Commission on Excellence in Education 1983) publicly damned the quality of teachers in the nation?s schools. ?Ironically, ?blaming? teachers for failure of American education reinforced the idea that teachers...

  1. Induction machine stray loss from inter-bar currents

    E-Print Network [OSTI]

    Englebretson, Steven Carl

    2009-01-01

    Stray load loss refers generally to the sources of induction machine loss not accounted for by typical calculations of primary or secondary copper loss, no load core loss, or friction and windage loss. Harmonic rotor bar ...

  2. Parallel resistivity and ohmic heating of laboratory dipole plasmas

    SciTech Connect (OSTI)

    Fox, W.

    2012-08-15

    The parallel resistivity is calculated in the long-mean-free-path regime for the dipole plasma geometry; this is shown to be a neoclassical transport problem in the limit of a small number of circulating electrons. In this regime, the resistivity is substantially higher than the Spitzer resistivity due to the magnetic trapping of a majority of the electrons. This suggests that heating the outer flux surfaces of the plasma with low-frequency parallel electric fields can be substantially more efficient than might be naively estimated. Such a skin-current heating scheme is analyzed by deriving an equation for diffusion of skin currents into the plasma, from which quantities such as the resistive skin-depth, lumped-circuit impedance, and power deposited in the plasma can be estimated. Numerical estimates indicate that this may be a simple and efficient way to couple power into experiments in this geometry.

  3. Ion Temperature Evolution in an Ultracold Neutral Plasma

    E-Print Network [OSTI]

    McQuillen, P; Langin, T; Killian, T C

    2015-01-01

    We study the long-time evolution of the ion temperature in an expanding ultracold neutral plasma using spatially resolved, laser-induced-fluorescence spectroscopy. Adiabatic cooling reduces the ion temperature by an order of magnitude during the plasma expansion, to temperatures as low as 0.2 K. Cooling is limited by heat exchange between ions and the much hotter electrons. We also present evidence for an additional heating mechanism and discuss possible sources. Data are described by a model of the plasma evolution, including the effects of ion-electron heat exchange. We show that for appropriate initial conditions, the degree of Coulomb coupling of ions in the plasma increases during expansion.

  4. Linear induction accelerator and pulse forming networks therefor

    DOE Patents [OSTI]

    Buttram, Malcolm T. (Sandia Park, NM); Ginn, Jerry W. (Albuquerque, NM)

    1989-01-01

    A linear induction accelerator includes a plurality of adder cavities arranged in a series and provided in a structure which is evacuated so that a vacuum inductance is provided between each adder cavity and the structure. An energy storage system for the adder cavities includes a pulsed current source and a respective plurality of bipolar converting networks connected thereto. The bipolar high-voltage, high-repetition-rate square pulse train sets and resets the cavities.

  5. Heat transfer enhancement resulting from induction electrohydrodynamic pumping 

    E-Print Network [OSTI]

    Margo, Bryan David

    1992-01-01

    HEAT TRANSFER ENHANCEMENT RESULTING FROM INDUCTION ELECTROHYDRODYNAMIC PUMPING A Thesis by BRYAN DAVID MARGO Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE December 1992 Major Subject: Mechanical Engineering HEAT TRANSFER ENHANCEMENT RESULTING FROM INDUCTION ELECTROHYDRODYNAMIC PUMPING A Thesis by BRYAN DAVID MARGO Approved as to style and content by: Jamal Seyed- Yagoobi (Chair...

  6. Plasma-sprayed coatings

    SciTech Connect (OSTI)

    Herman, H.

    1988-09-01

    Plasma spraying is one way to apply protective coatings. The hot, high-speed flame of a plasma gun can melt a powder of almost any ceramic or metal and spray it to form a coating for protection against corrosion, wear or high temperature. The technique carries much less risk of degrading the coating and substrate than many other high-temperature processes do, because the gas in the plasma flame is chemically inert and the target can be kept fairly cool. And yet a plasma gun can be only a little more cumbersome than a paint sprayer. Investigators are applying this technique to new materials. The General Electric Company is using vacuum plasma spraying to make freestanding components: intricate aircraft engine parts formed by plasma-spraying a superalloy on a removable substrate. Other workers spray ceramic particles or fibers and metal powder simulatious wrong, stiff composite materials: the ceramic particles dispersed in a matrix of metal. The author and colleagues at the U.S. Naval Research Laboratory have fabricated a thick film of high-temperature superconductor by plasma-spraying the compound in the form of a powder. 7 figs.

  7. Optical plasma microelectronic devices

    E-Print Network [OSTI]

    Forati, Ebrahim; Dill, Thyler; Sievenpiper, Dan

    2015-01-01

    The semiconductor channel in conventional microelectronic devices was successfully replaced with an optically triggered gas plasma channel. The combination of DC and laser-induced gas ionizations controls the conductivity of the channel, enabling us to realize different electronic devices such as transistors, switches, modulators, etc. A special micro-scale metasurface was used to enhance the laser-gas interaction, as well as combining it with DC ionization properly. Optical plasma devices benefit form the advantages of plasma/vacuum electronic devices while preserving most of the integrablity of semiconductor based devices.

  8. Self-shielding of a plasma-exposed surface during extreme transient heat loads

    SciTech Connect (OSTI)

    Zielinski, J. J.; Meiden, H. J. van der; Morgan, T. W.; Hoen, M. H. J. 't; De Temmerman, G.; Schram, D. C.

    2014-03-24

    The power deposition on a tungsten surface exposed to combined pulsed/continuous high power plasma is studied. A study of the correlation between the plasma parameters and the power deposition on the surface demonstrates the effect of particle recycling in the strongly coupled regime. Upon increasing the input power to the plasma source, the energy density to the target first increases then decreases. We suggest that the sudden outgassing of hydrogen particles from the target and their subsequent ionization causes this. This back-flow of neutrals impedes the power transfer to the target, providing a shielding of the metal surface from the intense plasma flux.

  9. Magnetic filter apparatus and method for generating cold plasma in semicoductor processing

    DOE Patents [OSTI]

    Vella, Michael C. (San Leandro, CA)

    1996-01-01

    Disclosed herein is a system and method for providing a plasma flood having a low electron temperature to a semiconductor target region during an ion implantation process. The plasma generator providing the plasma is coupled to a magnetic filter which allows ions and low energy electrons to pass therethrough while retaining captive the primary or high energy electrons. The ions and low energy electrons form a "cold plasma" which is diffused in the region of the process surface while the ion implantation process takes place.

  10. Development of a stable dielectric-barrier discharge enhanced laminar plasma jet generated at atmospheric pressure

    SciTech Connect (OSTI)

    Tang Jie; Li Shibo; Zhao Wei; Wang Yishan [State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics of CAS, Xi'an (China); Duan Yixiang [State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics of CAS, Xi'an (China); Research Center of Analytical Instrumentation, Sichuan University, Chengdu (China)

    2012-06-18

    A stable nonthermal laminar atmospheric-pressure plasma source equipped with dielectric-barrier discharge was developed to realize more efficient plasma generation, with the total energy consumption reduced to nearly 25% of the original. Temperature and emission spectra monitoring indicates that this plasma is uniform in the lateral direction of the jet core region. It is also found that this plasma contains not only abundant excited argon atoms but also sufficient excited N{sub 2} and OH. This is mainly resulted from the escape of abundant electrons from the exit, due to the sharp decrease of sustaining voltage and the coupling between ions and electrons.

  11. Prototyping Energy Efficient Thermo-Magnetic & Induction Hardening for Heat Treat & Net Shape Forming Applications

    SciTech Connect (OSTI)

    Aquil Ahmad

    2012-08-03

    Within this project, Eaton undertook the task of bringing about significant impact with respect to sustainability. One of the major goals for the Department of Energy is to achieve energy savings with a corresponding reduction in carbon foot print. The use of a coupled induction heat treatment with high magnetic field heat treatment makes possible not only improved performance alloys, but with faster processing times and lower processing energy, as well. With this technology, substitution of lower cost alloys for more exotic alloys became a possibility; microstructure could be tailored for improved magnetic properties or wear resistance or mechanical performance, as needed. A prototype commercial unit has been developed to conduct processing of materials. Testing of this equipment has been conducted and results demonstrate the feasibility for industrial commercialization.

  12. Nonlinear Dual-Mode Control of Variable-Speed Wind Turbines with Doubly Fed Induction Generators

    E-Print Network [OSTI]

    Tang, Choon Yik; Jiang, John N

    2010-01-01

    This paper presents a feedback/feedforward nonlinear controller for variable-speed wind turbines with doubly fed induction generators. By appropriately adjusting the rotor voltages and the blade pitch angle, the controller simultaneously enables: (a) control of the active power in both the maximum power tracking and power regulation modes, (b) seamless switching between the two modes, and (c) control of the reactive power so that a desirable power factor is maintained. Unlike many existing designs, the controller is developed based on original, nonlinear, electromechanically-coupled models of wind turbines, without attempting approximate linearization. Its development consists of three steps: (i) employ feedback linearization to exactly cancel some of the nonlinearities and perform arbitrary pole placement, (ii) design a speed controller that makes the rotor angular velocity track a desired reference whenever possible, and (iii) introduce a Lyapunov-like function and present a gradient-based approach for mini...

  13. PLASMA PHYSICS PPPL UC Davis

    E-Print Network [OSTI]

    PRINCETON PLASMA PHYSICS LABORATORY PPPL UC Davis PRINCETON PLASMA PHYSICS LABORATORY PPPL UC Davis Scattering System for ETG physics on NSTX H. Park, E. Mazzucato, and D. Smith PPPL, Princeton University C, 2006 Hyatt Regency, Dallas, TX #12;PRINCETON PLASMA PHYSICS LABORATORY PPPL UC Davis PRINCETON PLASMA

  14. Predicting high harmonic ion cyclotron heating efficiency in Tokamak plasmas

    SciTech Connect (OSTI)

    Green, David L [ORNL; Jaeger, E. F. [XCEL; Berry, Lee A [ORNL; Chen, Guangye [ORNL; Ryan, Philip Michael [ORNL; Canik, John [ORNL

    2011-01-01

    Observations of improved radio frequency (RF) heating efficiency in high-confinement (H-) mode plasmas on the National Spherical Tokamak Experiment (NSTX) are investigated by whole-device linear simulation. We present the first full-wave simulation to couple kinetic physics of the well confined core plasma to the poorly confined scrape-off plasma. The new simulation is used to scan the launched fast-wave spectrum and examine the steady-state electric wave field structure for experimental scenarios corresponding to both reduced, and improved RF heating efficiency. We find that launching toroidal wave-numbers that required for fast-wave propagation excites large amplitude (kVm 1 ) coaxial standing modes in the wave electric field between the confined plasma density pedestal and conducting vessel wall. Qualitative comparison with measurements of the stored plasma energy suggest these modes are a probable cause of degraded heating efficiency. Also, the H-mode density pedestal and fast-wave cutoff within the confined plasma allow for the excitation of whispering gallery type eigenmodes localised to the plasma edge.

  15. Mechanism of carbon nanostructure synthesis in arc plasma

    SciTech Connect (OSTI)

    Keidar, M.; Shashurin, A.; Volotskova, O.; Raitses, Y.; Beilis, I. I.

    2010-05-15

    Plasma enhanced techniques are widely used for synthesis of carbon nanostructures. The primary focus of this paper is to summarize recent experimental and theoretical advances in understanding of single-wall carbon nanotube (SWNT) synthesis mechanism in arcs, and to describe methods of controlling arc plasma parameters. Fundamental issues related to synthesis of SWNTs, which is a relationship between plasma parameters and SWNT characteristics are considered. It is shown that characteristics of synthesized SWNTs can be altered by varying plasma parameters. Effects of electrical and magnetic fields applied during SWNT synthesis in arc plasma are explored. Magnetic field has a profound effect on the diameter, chirality, and length of a SWNT synthesized in the arc plasma. An average length of SWNT increases by a factor of 2 in discharge with magnetic field and an amount of long nanotubes with the length above 5 {mu}m also increases in comparison with that observed in the discharge without a magnetic field. In addition, synthesis of a few-layer graphene in a magnetic field presence is discovered. A coupled model of plasma-electrode phenomena in atmospheric-pressure anodic arc in helium is described. Calculations indicate that substantial fraction of the current at the cathode is conducted by ions (0.7-0.9 of the total current). It is shown that nonmonotonic behavior of the arc current-voltage characteristic can be reproduced taking into account the experimentally observed dependence of the arc radius on arc current.

  16. Pulsed, atmospheric pressure plasma source for emission spectrometry

    DOE Patents [OSTI]

    Duan, Yixiang; Jin, Zhe; Su, Yongxuan

    2004-05-11

    A low-power, plasma source-based, portable molecular light emission generator/detector employing an atmospheric pressure pulsed-plasma for molecular fragmentation and excitation is described. The average power required for the operation of the plasma is between 0.02 W and 5 W. The features of the optical emission spectra obtained with the pulsed plasma source are significantly different from those obtained with direct current (dc) discharge higher power; for example, strong CH emission at 431.2 nm which is only weakly observed with dc plasma sources was observed, and the intense CN emission observed at 383-388 nm using dc plasma sources was weak in most cases. Strong CN emission was only observed using the present apparatus when compounds containing nitrogen, such as aniline were employed as samples. The present apparatus detects dimethylsulfoxide at 200 ppb using helium as the plasma gas by observing the emission band of the CH radical. When coupled with a gas chromatograph for separating components present in a sample to be analyzed, the present invention provides an apparatus for detecting the arrival of a particular component in the sample at the end of the chromatographic column and the identity thereof.

  17. Active plasma resonance spectroscopy: A functional analytic description

    E-Print Network [OSTI]

    Lapke, Martin; Mussenbrock, Thomas; Brinkmann, Ralf Peter

    2012-01-01

    The term "Active Plasma Resonance Spectroscopy" refers to a class of diagnostic methods which employ the ability of plasmas to resonate on or near the plasma frequency. The basic idea dates back to the early days of discharge physics: An signal in the GHz range is coupled to the plasma via an electrical probe; the spectral response is recorded, and then evaluated with a mathematical model to obtain information on the electron density and other plasma parameters. In recent years, the concept has found renewed interest as a basis of industry compatible plasma diagnostics. This paper analyzes the diagnostics technique in terms of a general description based on functional analytic (or Hilbert Space) methods which hold for arbitrary probe geometries. It is shown that the response function of the plasma-probe system can be expressed as a matrix element of the resolvent of an appropriately defined dynamical operator. A specialization of the formalism for a symmetric probe desing is given, as well as an interpreation...

  18. Laser Plasma Interactions

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    processes. A typical configuration uses a low intensity laser beam (2nd, 3rd, or 4th harmonic of 1054-nm) to probe a plasma volume. The Thomson scattered light is collected by a...

  19. Accelerating Particles with Plasma

    SciTech Connect (OSTI)

    Litos, Michael; Hogan, Mark

    2014-11-05

    Researchers at SLAC explain how they use plasma wakefields to accelerate bunches of electrons to very high energies over only a short distance. Their experiments offer a possible path for the future of particle accelerators.

  20. Simulation of Fusion Plasmas

    ScienceCinema (OSTI)

    Holland, Chris [UC San Diego, San Diego, California, United States

    2010-01-08

    The upcoming ITER experiment (www.iter.org) represents the next major milestone in realizing the promise of using nuclear fusion as a commercial energy source, by moving into the ?burning plasma? regime where the dominant heat source is the internal fusion reactions. As part of its support for the ITER mission, the US fusion community is actively developing validated predictive models of the behavior of magnetically confined plasmas. In this talk, I will describe how the plasma community is using the latest high performance computing facilities to develop and refine our models of the nonlinear, multiscale plasma dynamics, and how recent advances in experimental diagnostics are allowing us to directly test and validate these models at an unprecedented level.

  1. Plasma isotope separation methods

    SciTech Connect (OSTI)

    Grossman, M.W. ); Shepp, T.A. )

    1991-12-01

    Isotope separation has many important industrial, medical, and research applications. Large-scale processes have typically utilized complex cascade systems; for example, the gas centrifuge. Alternatively, high single-stage enrichment processes (as in the case of the calutron) are very energy intensive. Plasma-based methods being developed for the past 15 to 20 years have attempted to overcome these two drawbacks. In this review, six major types of isotope separation methods which involve plasma phenomena are discussed. These methods are: plasma centrifuge, AVLIS (atomic vapor laser isotope separation), ion wave, ICR (ion-cyclotron resonance), calutron, and gas discharge. The emphasis of this paper is to describe the plasma phenomena in these major categories. An attempt was made to include enough references so that more detailed study or evaluation of a particular method could readily be pursued. A brief discussion of isotope separation using mass balance concepts is also carried out.

  2. Plasma Screen Floating Mount

    DOE Patents [OSTI]

    Eakle, Robert F. (New Ellenton, SC); Pak, Donald J. (Martine, GA)

    2004-10-26

    A mounting system for a flat display screen, particularly a plasma display screen, suspends the screen separately in each of the x-, y- and z-directions. A series of frames located by linear bearings and isolated by springs and dampers allows separate controlled movement in each axis. The system enables the use of relatively larger display screens in vehicles in which plasma screen are subject to damage from vibration.

  3. Electrostatics of moving plasma

    SciTech Connect (OSTI)

    Ignatov, A. M.

    2013-07-15

    The stability of charge distribution over the surface of a conducting body in moving plasma is analyzed. Using a finite-width plate streamlined by a cold neutralized electron flow as an example, it is shown that an electrically neutral body can be unstable against the development of spontaneous polarization. The plasma parameters at which such instability takes place, as well as the frequency and growth rate of the fundamental mode of instability, are determined.

  4. Influence of Penning effect on the plasma features in a non-equilibrium atmospheric pressure plasma jet

    SciTech Connect (OSTI)

    Chang, Zhengshi; Zhang, Guanjun; Jiang, Nan; Cao, Zexian

    2014-03-14

    Non-equilibrium atmospheric pressure plasma jet (APPJ) is a cold plasma source that promises various innovative applications. The influence of Penning effect on the formation, propagation, and other physical properties of the plasma bullets in APPJ remains a debatable topic. By using a 10?cm wide active electrode and a frequency of applied voltage down to 0.5?Hz, the Penning effect caused by preceding discharges can be excluded. It was found that the Penning effect originating in a preceding discharge helps build a conductive channel in the gas flow and provide seed electrons, thus the discharge can be maintained at a low voltage which in turn leads to a smaller propagation speed for the plasma bullet. Photographs from an intensified charge coupled device reveal that the annular structure of the plasma plume for He is irrelevant to the Penning ionization process arising from preceding discharges. By adding NH{sub 3} into Ar to introduce Penning effect, the originally filamentous discharge of Ar can display a rather extensive plasma plume in ambient as He. These results are helpful for the understanding of the behaviors of non-equilibrium APPJs generated under distinct conditions and for the design of plasma jet features, especially the spatial distribution and propagation speed, which are essential for application.

  5. Dynamics of an Ion Coupled to a Parametric Superconducting Circuit

    E-Print Network [OSTI]

    Dvir Kafri; Prabin Adhikari; Jacob M. Taylor

    2015-04-15

    Superconducting circuits and trapped ions are promising architectures for quantum information processing. However, the natural frequencies for controlling these systems -- radio frequency ion control and microwave domain superconducting qubit control -- make direct Hamiltonian interactions between them weak. In this paper we describe a technique for coupling a trapped ion's motion to the fundamental mode of a superconducting circuit. We do this by applying a carefully modulated external magnetic flux to the circuit. In conjunction with a non-linear element (Josephson junction), this gives the circuit an effective time-dependent inductance. We then show how to tune the external flux to generate a resonant coupling between circuit and ion's motional mode, and discuss the limitations of this approach compared to using a time-dependent capacitance.

  6. Induction time effects in pulse combustors

    SciTech Connect (OSTI)

    Bell, J B; Marcus, D L; Pember, R B

    1999-04-09

    Combustion systems that take advantage of a periodic combustion process have many advantages over conventional systems. Their rate of heat transfer is greatly enhanced and their pollutant emissions are lower. They draw in their own supply of fuel and air and they are self-venting. They have few moving parts. The most common type of pulse combustor is based on a Helmholtz resonator - a burning cycle drives a resonant pressure wave, which in turn enhances the rate of combustion, resulting in a self-sustaining, large-scale oscillation. Although the basic physical mechanisms controlling such a process were explained by Rayleigh over a century ago, a full understanding of the operation of a pulse combustor still does not exist. The dominant processes in such a system--combustion, turbulent fluid dynamics, acoustics--are highly coupled and interact nonlinearly, which has reduced the design process to a costly and inefficient trial-and-error procedure. Several recent numerical and experimental studies, however, have been focused towards a better understanding of the basic underlying physics. Barr et al. [l] have elucidated the relative roles of the time scales governing the energy release, the turbulent mixing, and the acoustics. Keller et al. [5] have demonstrated the importance of the phase relation between the resonant pressure field in the tailpipe and the periodic energy release. Marcus et al. [6] have developed the capability for a fully three-dimensional simulation of the reacting flow in a pulse combustor. This paper is an application of that methodology to a detailed investigation of the frequency response of the model to changes in the chemical kinetics. The methodology consists of a fully conservative second-order Godunov algorithm for the inviscid, reacting gas dynamics equations coupled to an adaptive mesh refinement procedure[2]. The axisymmetric and three-dimensional simulations allow us to explore in detail the interaction between the transient fluid dynamics phenomena and the energy release associated with the combustion. For these simulations, we couple a second-order, unsplit Godunov algorithm for the inviscid, reacting gas dynamics equations to an adaptive Cartesian grid scheme[7]. In order to keep computational costs relatively low, we have developed a ''bootstrap'' procedure to initialize progressively higher-dimensional calculations. The quasi-one-dimensional code is run until transient phenomena have subsided and a desirable quasi-steady state has been achieved. The state data is then extrapolated to axisymmetric coordinates and these conditions used to initialize an axisymmetric calculation. The axisymmetric code is then run through several full combustion cycles and the data mapped to initialize a three-dimensional calculation.

  7. Mechanisms of plasma disruption and runaway electron losses in tokamaks

    E-Print Network [OSTI]

    Abdullaev, S S; Wongrach, K; Tokar, M; Koslowski, H R; Willi, O; Zeng, L

    2015-01-01

    Based on the analysis of data from the numerous dedicated experiments on plasma disruptions in the TEXTOR tokamak mechanisms of the formation of runaway electron beams and their losses are proposed. The plasma disruption is caused by strong stochastic magnetic field formed due to nonlinearly excited low-mode number MHD modes. It is hypothesized that the runaway electron beam is formed in the central plasma region confined inside the intact magnetic surface located between $q=1$ and the closest low--order rational [$q=4/3$ or $q=3/2$] magnetic surfaces. The thermal quench time caused by the fast electron transport in a stochastic magnetic field is calculated using the collisional transport model. The current decay stage is due to the ambipolar particle transport in a stochastic magnetic field. The runaway electron beam in the confined plasma region is formed due to their acceleration the inductive toroidal electric field. The runaway electron beam current is modeled as a sum of toroidally symmetric part and a ...

  8. Plasma phenomenology in astrophysical systems: Radio-sources and jets

    SciTech Connect (OSTI)

    Montani, Giovanni; Petitta, Jacopo

    2014-06-15

    We review the plasma phenomenology in the astrophysical sources which show appreciable radio emissions, namely Radio-Jets from Pulsars, Microquasars, Quasars, and Radio-Active Galaxies. A description of their basic features is presented, then we discuss in some details the links between their morphology and the mechanisms that lead to the different radio-emissions, investigating especially the role played by the plasma configurations surrounding compact objects (Neutron Stars, Black Holes). For the sake of completeness, we briefly mention observational techniques and detectors, whose structure set them apart from other astrophysical instruments. The fundamental ideas concerning angular momentum transport across plasma accretion disks—together with the disk-source-jet coupling problem—are discussed, by stressing their successes and their shortcomings. An alternative scenario is then inferred, based on a parallelism between astrophysical and laboratory plasma configurations, where small-scale structures can be found. We will focus our attention on the morphology of the radio-jets, on their coupling with the accretion disks and on the possible triggering phenomena, viewed as profiles of plasma instabilities.

  9. Graphene Coating Coupled Emission

    E-Print Network [OSTI]

    Shyamasundar, R.K.

    Graphene Coating Coupled Emission A COMSET, A single sheet of sp2-hybridized carbon atoms, called of graphene and its unique properties, I will present amplification of surface graphene-Ag hybrid films which when graphene is used as the spacer layer in a conventional Ag- harnessed the nonlinear properties

  10. PHYSICAL REVIEW E 85, 066402 (2012) Frequency-dependent shear viscosity of a liquid two-dimensional dusty plasma

    E-Print Network [OSTI]

    Goree, John

    2012-01-01

    of a liquid for a particular time scale -1 . A simple model of the frequency-dependent viscosity is predicted-feng@uiowa.edu magnetically in a Penning trap [16], vortex arrays in the mixed state of type II superconductors [17], and strongly coupled dusty plasmas levitated in a single layer [11,18]. A dusty plasma [19­25], sometimes

  11. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 37, NO. 12, DECEMBER 2009 2303 Nitric Oxide Formation in a Premixed Flame With

    E-Print Network [OSTI]

    Lee, Tonghun

    IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 37, NO. 12, DECEMBER 2009 2303 Nitric Oxide Formation in a Premixed Flame With High-Level Plasma Energy Coupling Xing Rao, Igor B. Matveev, and Tonghun Lee Abstract) in a transient-arc direct-current plasmatron igniter using premixed air/fuel mixtures. Quantitative measurements

  12. Bifurcation and control of chaos in Induction motor drives

    E-Print Network [OSTI]

    Krishnendu Chakrabarty; Urmila Kar

    2014-10-24

    The induction motor controlled by Indirect Field Oriented Control (IFOC) is known to have high performance and better stability. This paper reports the dynamical behavior of an indirect field oriented control (IFOC) induction motor drive in the light of bifurcation theory. The speed of high performance induction motor drive is controlled by IFOC method. The knowledge of qualitative change of the behavior of the motor such as equilibrium points, limit cycles and chaos with the change of motor parameters and load torque are essential for proper control of the motor. This paper provides a numerical approach to understand better the dynamical behavior of an indirect field oriented control of a current-fed induction motor. The focus is on bifurcation analysis of the IFOC motor, with a particular emphasis on the change that affects the dynamics and stability under small variations of Proportional Integral controller (PI) parameters, load torque and k, the ratio of the rotor time constant and its estimate etc. Bifurcation diagrams are computed. This paper also attempts to discuss various types of the transition to chaos in the induction motor. The results of the obtained bifurcation simulations give useful guidelines for adjusting both motor model and PI controller parameters. It is also important to ensure desired operation of the motor when the motor shows chaotic behavior. Infinite numbers of unstable periodic orbits are embedded in a chaotic attractor. Any unstable periodic orbit can be stabilized by proper control algorithm. The delayed feedback control method to control chaos has been implemented in this system.

  13. The effect of plasma flow on line-tied magnetohydrodynamic modes

    SciTech Connect (OSTI)

    Arcudi, Francesco [Dipartimento di Energetica, Politecnico di Torino, 10129 Torino (Italy); Delzanno, Gian Luca; Finn, John M. [T-5, Applied Mathematics and Plasma Physics Group, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2010-06-15

    The linear stability of a linear pinch to kink modes with line-tying boundary conditions and equilibrium axial flow is studied. Numerical results in visco-resistive magnetohydrodynamics show that for long plasmas, in which the line-tying stabilization effect is weak, plasma flow is stabilizing. For shorter plasmas, near the length at which line-tying stabilizes the mode for zero flow, the flow can be destabilizing. A simple model using reduced ideal magnetohydrodynamics with a step-function current density and an even simpler one-dimensional sound wave model with equilibrium flow elucidate these effects. It is concluded that: (1) The stabilization in long plasmas is due to convective stabilization; (2) the destabilization for short plasmas can be explained using a picture involving the coupling of two stable waves, one propagating in the forward direction and one in the backward direction; and (3) strong magnetic shear suppresses the flow destabilization for short plasmas.

  14. Metal plasmas for the fabrication of nanostructures

    E-Print Network [OSTI]

    Anders, Andre

    2006-01-01

    10] Anders A, Cathodic Arc Plasma Deposition: From Fractalalmost all cathodic arc plasmas contain multiply chargedconsider filtered cathodic arc plasma. The first report on

  15. Atomic scale heating in energetic plasma deposition

    E-Print Network [OSTI]

    Anders, Andre

    2001-01-01

    equation (2), for cathodic arc plasmas. The kinetic energiesscale heating in cathodic arc plasma deposition André Andersscale heating in cathodic arc plasma deposition André Anders

  16. Plasma jet ignition device

    DOE Patents [OSTI]

    McIlwain, Michael E. (Franklin, MA); Grant, Jonathan F. (Wayland, MA); Golenko, Zsolt (North Reading, MA); Wittstein, Alan D. (Fairfield, CT)

    1985-01-15

    An ignition device of the plasma jet type is disclosed. The device has a cylindrical cavity formed in insulating material with an electrode at one end. The other end of the cylindrical cavity is closed by a metal plate with a small orifice in the center which plate serves as a second electrode. An arc jumping between the first electrode and the orifice plate causes the formation of a highly-ionized plasma in the cavity which is ejected through the orifice into the engine cylinder area to ignite the main fuel mixture. Two improvements are disclosed to enhance the operation of the device and the length of the plasma plume. One improvement is a metal hydride ring which is inserted in the cavity next to the first electrode. During operation, the high temperature in the cavity and the highly excited nature of the plasma breaks down the metal hydride, liberating hydrogen which acts as an additional fuel to help plasma formation. A second improvement consists of a cavity insert containing a plurality of spaced, metal rings. The rings act as secondary spark gap electrodes reducing the voltage needed to maintain the initial arc in the cavity.

  17. A recipe for Hamiltonian of system-environment coupling applicable to ultrastrong light-matter interaction regime

    E-Print Network [OSTI]

    Motoaki Bamba; Tetsuo Ogawa

    2013-11-06

    When the light interacts with matters in a lossy cavity, in the standard cavity quantum electrodynamics, the dissipation of cavity fields is characterized simply by the strengths of the two couplings: the light-matter interaction and the system-environment coupling through the cavity mirror. However, in the ultrastrong light-matter interaction regime, the dissipation depends also on whether the two couplings are mediated by the electric field or the magnetic one (capacitive or inductive in superconducting circuits). Even if we know correctly the microscopic mechanism (Lagrangian) of the system-environment coupling, the coupling Hamiltonian itself is in principle modified due to the ultrastrong interaction in the cavity. In this paper, we show a recipe for deriving a general expression of the Hamiltonian of the system-environment coupling, which is applicable even in the ultrastrong light-matter interaction regime in the good-cavity and independent-transition limit.

  18. Power and Particle Exhaust in Tokamaks: Integration of Plasma Scenarios with Plasma Facing Materials and Components

    E-Print Network [OSTI]

    Power and Particle Exhaust in Tokamaks: Integration of Plasma Scenarios with Plasma Facing Materials and Components

  19. Effects of Plasma Dielectric Properties on Thomson Scattering of Millimetre Waves in Tokamak Plasmas

    E-Print Network [OSTI]

    Effects of Plasma Dielectric Properties on Thomson Scattering of Millimetre Waves in Tokamak Plasmas

  20. 2013 Plasma Camp | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-InspiredAtmosphericdevicesPPONeApril 30, 2013 9:30 am -NationalPlasma Camp View

  1. Basic Plasma Science | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory of raregovAboutRecovery ActTools toBadging, Badge Office Badging,Basic Plasma

  2. Heating mode transition in a hybrid direct current/dual-frequency capacitively coupled CF{sub 4} discharge

    SciTech Connect (OSTI)

    Zhang, Quan-Zhi; Wang, You-Nian; Bogaerts, Annemie

    2014-06-14

    Computer simulations based on the particle-in-cell/Monte Carlo collision method are performed to study the plasma characteristics and especially the transition in electron heating mechanisms in a hybrid direct current (dc)/dual-frequency (DF) capacitively coupled CF{sub 4} discharge. When applying a superposed dc voltage, the plasma density first increases, then decreases, and finally increases again, which is in good agreement with experiments. This trend can be explained by the transition between the four main heating modes, i.e., DF coupling, dc and DF coupling, dc source dominant heating, and secondary electron dominant heating.

  3. Fundamentals of plasma simulation

    SciTech Connect (OSTI)

    Forslund, D.W.

    1985-01-01

    With the increasing size and speed of modern computers, the incredibly complex nonlinear properties of plasmas in the laboratory and in space are being successfully explored in increasing depth. Of particular importance have been numerical simulation techniques involving finite size particles on a discrete mesh. After discussing the importance of this means of understanding a variety of nonlinear plasma phenomena, we describe the basic elements of particle-in-cell simulation and their limitations and advantages. The differencing techniques, stability and accuracy issues, data management and optimization issues are discussed by means of a simple example of a particle-in-cell code. Recent advances in simulation methods allowing large space and time scales to be treated with minimal sacrifice in physics are reviewed. Various examples of nonlinear processes successfully studied by plasma simulation will be given.

  4. Dynamical Yukawa Couplings

    E-Print Network [OSTI]

    Rodrigo Alonso

    2013-07-07

    The matter content of the Standard Model admits a global symmetry due to the generational structure of the spectrum respected by all interactions except for fermion couplings to the Higgs doublet. This symmetry is identified as the largest possible global symmetry of the free theory and extended to the case of massive neutrinos. The violation of such symmetry is then assumed dynamical and the value of the Yukawa couplings is fixed by a variational principle. This ansatz yields compelling results: Quark Yukawas naturally accommodate hierarchical masses and small mixing whereas Lepton Yukawas exhibit a hierarchical pattern for charged leptons and simultaneously degeneracy in the neutrino sector correlated with large mixing and Majorana phases. The difference in the mixing patterns of Quark and Leptons in this scheme stem from the Dirac vs Majorana nature of fermions.

  5. An analytical demonstration of coupling schemes between magnetohydrodynamic codes and eddy current codes

    SciTech Connect (OSTI)

    Liu Yueqiang [Euratom/UKAEA Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Albanese, R.; Rubinacci, G. [ENEA/CREATE, Universita Federico II di Napoli, Via Claudio 21, Napoli (Italy); Portone, A. [EFDA-CSU Barcelona, C/Josep Pla 2, B3, 08019 Barcelona (Spain); Villone, F. [ENEA/CREATE, DAEIMI, Universita di Cassino, Via di Biasio 43, Cassino (Italy)

    2008-07-15

    In order to model a magnetohydrodynamic (MHD) instability that strongly couples to external conducting structures (walls and/or coils) in a fusion device, it is often necessary to combine a MHD code solving for the plasma response, with an eddy current code computing the fields and currents of conductors. We present a rigorous proof of the coupling schemes between these two types of codes. One of the coupling schemes has been introduced and implemented in the CARMA code [R. Albanese, Y. Q. Liu, A. Portone, G. Rubinacci, and F. Villone, IEEE Trans. Magn. 44, 1654 (2008); A. Portone, F. Villone, Y. Q. Liu, R. Albanese, and G. Rubinacci, Plasma Phys. Controlled Fusion 50, 085004 (2008)] that couples the MHD code MARS-F[Y. Q. Liu, A. Bondeson, C. M. Fransson, B. Lennartson, and C. Breitholtz, Phys. Plasmas 7, 3681 (2000)] and the eddy current code CARIDDI[R. Albanese and G. Rubinacci, Adv. Imaging Electron Phys. 102, 1 (1998)]. While the coupling schemes are described for a general toroidal geometry, we give the analytical proof for a cylindrical plasma.

  6. Plasma Simulation Program

    SciTech Connect (OSTI)

    Greenwald, Martin

    2011-10-04

    Many others in the fusion energy and advanced scientific computing communities participated in the development of this plan. The core planning team is grateful for their important contributions. This summary is meant as a quick overview the Fusion Simulation Program's (FSP's) purpose and intentions. There are several additional documents referenced within this one and all are supplemental or flow down from this Program Plan. The overall science goal of the DOE Office of Fusion Energy Sciences (FES) Fusion Simulation Program (FSP) is to develop predictive simulation capability for magnetically confined fusion plasmas at an unprecedented level of integration and fidelity. This will directly support and enable effective U.S. participation in International Thermonuclear Experimental Reactor (ITER) research and the overall mission of delivering practical fusion energy. The FSP will address a rich set of scientific issues together with experimental programs, producing validated integrated physics results. This is very well aligned with the mission of the ITER Organization to coordinate with its members the integrated modeling and control of fusion plasmas, including benchmarking and validation activities. [1]. Initial FSP research will focus on two critical Integrated Science Application (ISA) areas: ISA1, the plasma edge; and ISA2, whole device modeling (WDM) including disruption avoidance. The first of these problems involves the narrow plasma boundary layer and its complex interactions with the plasma core and the surrounding material wall. The second requires development of a computationally tractable, but comprehensive model that describes all equilibrium and dynamic processes at a sufficient level of detail to provide useful prediction of the temporal evolution of fusion plasma experiments. The initial driver for the whole device model will be prediction and avoidance of discharge-terminating disruptions, especially at high performance, which are a critical impediment to successful operation of machines like ITER. If disruptions prove unable to be avoided, their associated dynamics and effects will be addressed in the next phase of the FSP.

  7. Magnetic coupling device

    DOE Patents [OSTI]

    Nance, Thomas A. (Aiken, SC)

    2009-08-18

    A quick connect/disconnect coupling apparatus is provided in which a base member is engaged by a locking housing through a series of interengagement pins. The pins maintain the shaft in a locked position. Upon exposure to an appropriately positioned magnetic field, pins are removed a sufficient distance such that the shaft may be withdrawn from the locking housing. The ability to lock and unlock the connector assembly requires no additional tools or parts apart from a magnetic key.

  8. Atomic oxygen patterning from a biomedical needle-plasma source

    SciTech Connect (OSTI)

    Kelly, Seán; Turner, Miles M.

    2013-09-28

    A “plasma needle” is a cold plasma source operating at atmospheric pressure. Such sources interact strongly with living cells, but experimental studies on bacterial samples show that this interaction has a surprising pattern resulting in circular or annular killing structures. This paper presents numerical simulations showing that this pattern occurs because biologically active reactive oxygen and nitrogen species are produced dominantly where effluent from the plasma needle interacts with ambient air. A novel solution strategy is utilised coupling plasma produced neutral (uncharged) reactive species to the gas dynamics solving for steady state profiles at the treated biological surface. Numerical results are compared with experimental reports corroborating evidence for atomic oxygen as a key bactericidal species. Surface losses are considered for interaction of plasma produced reactants with reactive solid and liquid interfaces. Atomic oxygen surface reactions on a reactive solid surface with adsorption probabilities above 0.1 are shown to be limited by the flux of atomic oxygen from the plasma. Interaction of the source with an aqueous surface showed hydrogen peroxide as the dominant species at this interface.

  9. A linear helicon plasma device with controllable magnetic field gradient

    SciTech Connect (OSTI)

    Barada, Kshitish K.; Chattopadhyay, P. K.; Ghosh, J.; Kumar, Sunil; Saxena, Y. C. [Institute for Plasma Research, Bhat, Gandhinagar, Gujarat 382428 (India)

    2012-06-15

    Current free double layers (CFDLs) are localized potential structures having spatial dimensions - Debye lengths and potential drops of more than local electron temperature across them. CFDLs do not need a current for them to be sustained and hence they differ from the current driven double layers. Helicon antenna produced plasmas in an expanded chamber along with an expanding magnetic field have shown the existence of CFDL near the expansion region. A helicon plasma device has been designed, fabricated, and installed in the Institute for Plasma Research, India to study the role of maximum magnetic field gradient as well as its location with respect to the geometrical expansion region of the chamber in CFDL formation. The special feature of this machine consisting of two chambers of different radii is its capability of producing different magnetic field gradients near the physical boundary between the two chambers either by changing current in one particular coil in the direction opposite to that in other coils and/or by varying the position of this particular coil. Although, the machine is primarily designed for CFDL experiments, it is also capable of carrying out many basic plasma physics experiments such as wave propagation, wave coupling, and plasma instabilities in a varying magnetic field topology. In this paper, we will present the details of the machine construction, its specialties, and some preliminary results about the production and characterization of helicon plasma in this machine.

  10. The interaction of intense subpicosecond laser pulses with underdense plasmas

    SciTech Connect (OSTI)

    Coverdale, C.A.

    1995-05-11

    Laser-plasma interactions have been of interest for many years not only from a basic physics standpoint, but also for their relevance to numerous applications. Advances in laser technology in recent years have resulted in compact laser systems capable of generating (psec), 10{sup 16} W/cm{sup 2} laser pulses. These lasers have provided a new regime in which to study laser-plasma interactions, a regime characterized by L{sub plasma} {ge} 2L{sub Rayleigh} > c{tau}. The goal of this dissertation is to experimentally characterize the interaction of a short pulse, high intensity laser with an underdense plasma (n{sub o} {le} 0.05n{sub cr}). Specifically, the parametric instability known as stimulated Raman scatter (SRS) is investigated to determine its behavior when driven by a short, intense laser pulse. Both the forward Raman scatter instability and backscattered Raman instability are studied. The coupled partial differential equations which describe the growth of SRS are reviewed and solved for typical experimental laser and plasma parameters. This solution shows the growth of the waves (electron plasma and scattered light) generated via stimulated Raman scatter. The dispersion relation is also derived and solved for experimentally accessible parameters. The solution of the dispersion relation is used to predict where (in k-space) and at what frequency (in {omega}-space) the instability will grow. Both the nonrelativistic and relativistic regimes of the instability are considered.

  11. Plasma heating power dissipation in low temperature hydrogen plasmas

    E-Print Network [OSTI]

    Komppula, J

    2015-01-01

    Theoretical framework for power dissipation in low temperature plasmas in corona equilibrium is developed. The framework is based on fundamental conservation laws and reaction cross sections and is only weakly sensitive to plasma parameters, e.g. electron temperature and density. The theory is applied to low temperature atomic and molecular hydrogen laboratory plasmas for which the plasma heating power dissipation to photon emission, ionization and chemical potential is calculated. The calculated photon emission is compared to recent experimental results.

  12. Quick torque coupling

    DOE Patents [OSTI]

    Luft, Peter A. (El Cerrito, CA)

    2009-05-12

    A coupling for mechanically connecting modular tubular struts of a positioning apparatus or space frame, comprising a pair of toothed rings (10, 12) attached to separate strut members (16), the teeth (18, 20) of the primary rings (10, 12) mechanically interlocking in both an axial and circumferential manner, and a third part comprising a sliding, toothed collar (14) the teeth (22) of which interlock the teeth (18, 20) of the primary rings (10, 12), preventing them from disengaging, and completely locking the assembly together. A secondary mechanism provides a nesting force for the collar, and/or retains it. The coupling is self-contained and requires no external tools for installation, and can be assembled with gloved hands in demanding environments. No gauging or measured torque is required for assembly. The assembly can easily be visually inspected to determine a "go" or "no-go" status. The coupling is compact and relatively light-weight. Because of it's triply interlocking teeth, the connection is rigid. The connection does not primarily rely on clamps, springs or friction based fasteners, and is therefore reliable in fail-safe applications.

  13. Plasma diagnostic reflectometry

    SciTech Connect (OSTI)

    Cohen, B.I.; Afeyan, B.B.; Garrison, J.C.; Kaiser, T.B.; Luhmann, N.C. Jr.; Domier, C.W.; Chou, A.E.; Baang, S.

    1996-02-26

    Theoretical and experimental studies of plasma diagnostic reflectometry have been undertaken as a collaborative research project between the Lawrence Livermore National Laboratory (LLNL) and the University of California Department of Applied Science Plasma Diagnostics Group under the auspices of the Laboratory Directed Research and Development Program at LLNL. Theoretical analyses have explored the basic principles of reflectometry to understand its limitations, to address specific gaps in the understanding of reflectometry measurements in laboratory experiments, and to explore extensions of reflectometry such as ultra-short-pulse reflectometry. The theory has supported basic laboratory reflectometry experiments where reflectometry measurements can be corroborated by independent diagnostic measurements.

  14. Bransen Plasma Asher

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 OutreachProductswsicloudwsiclouddenDVA N C E D B L OBransen Plasma Asher An O2 RF plasma can be used at CAMD to

  15. Study on the Mechanical Instability of MICE Coupling Magnets

    SciTech Connect (OSTI)

    Wang, Li; Pan, Heng; Gou, Xing Long; Wu, Hong; Zheng, Shi Xian; Green, Michael A

    2011-05-04

    The superconducting coupling solenoid magnet is one of the key equipment in the Muon Ionization Cooling Experiment (MICE). The coil has an inner radius of 750 mm, length of 281 mm and thickness of 104 mm at room temperature. The peak induction in the coil is about 7.3 T with a full current of 210 A. The mechanical disturbances which might cause the instability of the impregnated superconducting magnet involve the frictional motion between conductors and the cracking of impregnated materials. In this paper, the mechanical instability of the superconducting coupling magnet was studied. This paper presents the numerical calculation results of the minimum quench energy (MQE) of the coupling magnet, as well as the dissipated strain energy in the stress concentration region when the epoxy cracks and the frictional energy caused by 'stick-slip' of the conductor based on the bending theory of beam happens. Slip planes are used in the coupling coil and the frictional energy due to 'slow slip' at the interface of the slip planes was also investigated. The dissipated energy was compared with MQE, and the results show that the cracking of epoxy resin in the region of shear stress concentration is the main factor for premature quench of the coil.

  16. Backreaction effects due to matter coupled higher derivative gravity

    E-Print Network [OSTI]

    Lata Kh Joshi; P. Ramadevi

    2014-11-28

    AdS-hydrodynamics has proven to be a useful tool for obtaining transport coefficients observed in the collective flow of strongly coupled fluids like quark gluon plasma (QGP). Particularly, the ratio of shear viscosity to entropy density ${\\eta/ s}$ obtained from elliptic flow measurements can be matched with the computation done in the dual gravity theory. The experimentally observed temperature dependence of ${\\eta/ s}$ requires the study of scalar matter coupled AdS gravity including higher derivative curvature corrections. We obtain the backreaction to the metric for such a matter coupled AdS gravity in $D$-dimensional spacetime due to the higher derivative curvature corrections. Then, we present the backreaction corrections to shear-viscosity $\\eta$ and entropy density $s$.

  17. High Energy Density Laboratory Plasmas

    E-Print Network [OSTI]

    High Energy Density Laboratory Plasmas General Plasma Science Developing founda/ons and advancing fundamental understanding #12;The High Energy Density developing innovative techniques to study the properties of instabilities in magnetized-high-energy-density

  18. Computational study of flow dynamics from a dc arc plasma jet

    E-Print Network [OSTI]

    Trelles, Juan Pablo

    2013-01-01

    Plasma jets produced by direct-current (DC) non-transferred arc plasma torches, at the core of technologies ranging from spray coating to pyrolysis, present intricate dynamics due to the coupled interaction of fluid flow, thermal, and electromagnetic phenomena. The flow dynamics from an arc discharge plasma jet are investigated using time-dependent three-dimensional simulations encompassing the dynamics of the arc inside the torch, the evolution of the jet through the discharge environment, and the subsequent impingement of the jet over a flat substrate. The plasma is described by a chemical equilibrium and thermodynamic nonequilibrium (two-temperature) model. The numerical formulation of the physical model is based on a monolithic and fully-coupled treatment of the fluid and electromagnetic equations using a Variational Multiscale Finite Element Method. Simulation results uncover distinct aspects of the flow dynamics, including the jet forcing due to the movement of the electric arc, the prevalence of deviat...

  19. Instabilities and pattern formation in lowtemperature plasmas

    E-Print Network [OSTI]

    of the plasma region is approximately 20cm. (Produced by the Plasma Research Laboratory, Dublin City University

  20. PRINCETON PLASMA PHYSICS LABORATORY

    E-Print Network [OSTI]

    Budny, Robert

    Pressure(MPa) Major Radius (m) Transition time 2.0 2.5 Tim e (s) 2.0 3.0 2.0 3.0 With transition: ERS calculation includes off-diagonal contributions · Orbit squeezing effects from Shaing et al. [Phys. Plasmas 1 values calculated by NCLASS code Particle Diffusivities for Trace T and He Approach Neoclassical Levels

  1. Turbulence & Transport in Burning Plasmas

    E-Print Network [OSTI]

    , General Atomics, U. Maryland, PPPL, U. Colorado, UCLA, U. Texas) DOE Scientific Discovery Through Advanced Sciences, SciDAC (Scientific Discovery Through Advanced Computing) Project · devoted to studying plasma of toroidal plasma: plasma = heavy fluid B = "light fluid" geff = centrifugal force R v 2 R Growth rate: RLRLL

  2. Controlled zone microwave plasma system

    DOE Patents [OSTI]

    Ripley, Edward B. (Knoxville, TN); Seals, Roland D. (Oak Ridge, TN); Morrell, Jonathan S. (Knoxville, TN)

    2009-10-20

    An apparatus and method for initiating a process gas plasma. A conductive plate having a plurality of conductive fingers is positioned in a microwave applicator. An arc forms between the conductive fingers to initiate the formation of a plasma. A transport mechanism may convey process materials through the plasma. A spray port may be provided to expel processed materials.

  3. I. Introduction Equivalent loading of induction machines are

    E-Print Network [OSTI]

    Szabados, Barna

    phase synchronous machine. If the synchronous machine had a rotor with two windings with a spacial phaseI. Introduction Equivalent loading of induction machines are used to test machines for temperature loading tests, lead to the conclusion that synthetic loading is a viable simple test for large machines

  4. Verifying Concurrent Programs via Bounded Context-Switching and Induction

    E-Print Network [OSTI]

    Reps, Thomas W.

    on and extends context- bounded analysis (CBA), in which thread interleavings are consid- ered only up to K switch). Our approach uses CBA directly to handle the base case, and uses CBA as a subroutine when impediments to combining CBA and K-induction. The paper identifies these challenges and introduces three

  5. Applications of the Array Induction Tool in Saudi Arabia

    SciTech Connect (OSTI)

    Zainalabedin, K.A. [Saudi Aramco, Dhahran (Saudi Arabia); Cao Minh, C.

    1995-11-01

    Since its introduction in Saudi Arabia in 1993, the Array Induction Tool (AIT) has been run extensively in a wide variety of petrophysical environments. These include fresh mud, salty mud, high and low resistivity formations, hydrocarbon-bearing or water-bearing reservoirs in carbonates and clastics sequences. In some examples, the AIT was also run in conjunction with the Phasor Induction (PI) or Dual-Laterolog for comparison purpose. As with any resistivity device, the AIT`s primary product, an accurate Rt measurement, should not be overlooked. However, owing to the AIT`s multiple vertical resolutions and depths of investigation, the authors found that the tool yields additional information about the reservoirs that is not possible with older induction tools. The AIT improves the estimation of Rt in cases of thin laminations, complex invasion profiles or when the borehole correction is critical (wash-out, salty mud, high resistivity). In many instances, permeable beds that are invaded are much easier to identify with the AIT than with dual depths of investigation induction or laterolog tools. a typical case is the interpretation of annulus. Finally, they show the AIT characteristic response in a thing magnetic marker.

  6. Indices to detect Hopf bifurcation in Induction motor drives

    E-Print Network [OSTI]

    Krishnendu Chakrabarty; Urmila Kar

    2014-10-24

    The loss of stability of induction motor controlled by Indirect Field Oriented Control (IFOC) is a matter of great concern of operators and design engineers. This paper reports indices to detect and predict stability problem such as system oscillations. Oscillations as a result of loss of stability, due to Hopf bifurcation, for different parameter values of IFOC motor are studied using the proposed indices.

  7. Inductively heated particulate matter filter regeneration control system

    DOE Patents [OSTI]

    Gonze, Eugene V; Paratore Jr., Michael J; Kirby, Kevin W; Phelps, Amanda; Gregoire, Daniel J

    2012-10-23

    A system includes a particulate matter (PM) filter with an upstream end for receiving exhaust gas, a downstream end and zones. The system also includes a heating element. A control module selectively activates the heating element to inductively heat one of the zones.

  8. Plasticity constrained: over-generalized induction cues cause maladaptive phenotypes

    E-Print Network [OSTI]

    DeWitt, Thomas J.

    Plasticity constrained: over-generalized induction cues cause maladaptive phenotypes R. Brian TAMU, College Station, TX 77843-2258, USA ABSTRACT The adaptive value of phenotypic plasticity depends) may be a major constraint on the evolution of phenotypic plasticity. Furthermore, these induced

  9. Induction to the Third Year Dr Peter Tino

    E-Print Network [OSTI]

    Tino, Peter

    1 Induction to the Third Year Dr Peter Tino Director of Undergraduate Studies School of Computer Module(s) Getting to the Third Year #12;3 Progression Rules · University regulations are the definitive will use the appropriate one when the resit results are known. #12;6 Preparing for the Third Year · Choose

  10. Journal of Philosophy, Inc. Implications of Personal Probability for Induction

    E-Print Network [OSTI]

    Barrett, Jeffrey A.

    Journal of Philosophy, Inc. Implications of Personal Probability for Induction Author(s): Leonard J. Savage Source: The Journal of Philosophy, Vol. 64, No. 19, Sixty-Fourth Annual Meeting of the American Philosophical Association, Eastern Division (Oct. 5, 1967), pp. 593-607 Published by: Journal of Philosophy, Inc

  11. Latent-Descriptor Clustering for Unsupervised POS Induction Michael Lamar

    E-Print Network [OSTI]

    Bienenstock, Elie

    Latent-Descriptor Clustering for Unsupervised POS Induction Michael Lamar Department of Mathematics unsupervised, POS tagging, based on an adaptation of the EM algorithm for the esti- mation of a Gaussian evaluation criteria for unsupervised POS tagging, LDC shows a substantial im- provement in performance over

  12. NEAR-SURFACE CONTROLLED-SOURCE ELECTROMAGNETIC INDUCTION

    E-Print Network [OSTI]

    Meju, Max

    -D and advanced 3-D forward modeling and inversion for more detailed analyses. Previous reviews. EVERETT Dept. of Geology and Geophysics, Texas A&M University College Station TX 77843 U.S.A. MAX A. MEJU The controlled-source electromagnetic (CSEM) induction method is emerging as a leading geophysical technique

  13. Fast NarrowingDriven Partial Evaluation for Inductively Sequential Programs

    E-Print Network [OSTI]

    Vidal, Germán

    ). In this work, we introduce a faster partial evaluation scheme by ensuring the termination of the process evaluation---only contain finitely many different terms (and, thus, partial evaluation terminates). SinceFast Narrowing­Driven Partial Evaluation for Inductively Sequential Programs J. Guadalupe Ramos

  14. Event Year Requirements Induction 1 mandatory; 10 training points

    E-Print Network [OSTI]

    Obbard, Darren

    /masterclass 30 training points (module I); 50 training points (module I and II) 20 hours Training strand 3Event Year Requirements Induction 1 mandatory; 10 training points Symposium All mandatory; 20 training points in Y1 only Training strand 1: Research skills Thematic group meetings (4) Advanced

  15. Ethanol Tolerance Caused by slowpoke Induction in Drosophila

    E-Print Network [OSTI]

    Atkinson, Nigel

    Ethanol Tolerance Caused by slowpoke Induction in Drosophila Roshani B. Cowmeadow, Harish R in the ethanol response. Caenorhabditis elegans carrying mutations in this gene have altered ethanol sensitivity and Drosophila mutant for this gene are unable to acquire rapid tolerance to ethanol or anesthetics

  16. An Inductive Database Prototype Based on Virtual Mining Views

    E-Print Network [OSTI]

    Robardet, Céline

    An Inductive Database Prototype Based on Virtual Mining Views Hendrik Blockeel K.U. Leuven Leuven, Belgium Toon Calders T.U. Eindhoven Eindhoven, The Netherlands Elisa Fromont K.U. Leuven Leuven, Belgium Bart Goethals Universiteit Antwerpen Antwerp, Belgium Adriana Prado Universiteit Antwerpen Antwerp

  17. Plasma-chemical waste treatment of acid gases

    SciTech Connect (OSTI)

    Harkness, J.B.L.; Doctor, R.D.; Daniels, E.J.

    1993-09-01

    The research to date has shown that a H{sub 2}S waste-treatment process based on plasma-chemical dissociation technology is compatible with refinery and high-carbon-oxide acid-gas streams. The minor amounts of impurities produced in the plasma-chemical reactor should be treatable by an internal catalytic reduction step. Furthermore, the plasma-chemical technology appears to be more efficient and more economical than the current technology. The principal key to achieving high conversions with relatively low energies of dissociation is the concept of the high-velocity, cyclonic-flow pattern in the plasma reaction zone coupled with the recycling of unconverted hydrogen sulfide. Future work will include testing the effects of components that might be carried over to the plasma reactor by ``upset`` conditions in the amine purification system of a plant and testing the plasma-chemical process on other industrial wastes streams that contain potentially valuable chemical reagents. The strategy for the commercialization of this technology is to form a Cooperative Research and Development Agreement with the Institute of Hydrogen Energy and Plasma Technology of the Russian Scientific Center/Kurchatov Institute and with an American start-up company to develop an ``American`` version of the process and to build a commercial-scale demonstration unit in the United States. The timetable proposed would involve building a ``field test`` facility which would test the plasma-chemical reactor and sulfur recovery unit operations on an industrial hydrogen sulfide waste s at a scale large enough to obtain the energy and material balance data required for a final analysis of the commercial potential of this technology. The field test would then be followed by construction of a commercial demonstration unit in two to three years. The commercial demonstration unit would be a fully integrated plant consisting of one commercial-scale module.

  18. Fluctuations and intermittent poloidal transport in a simple toroidal plasma

    SciTech Connect (OSTI)

    Goud, T. S.; Ganesh, R.; Saxena, Y. C.; Raju, D. [Institute for Plasma Research, Gandhi nagar, Gujarat 382428 (India)] [Institute for Plasma Research, Gandhi nagar, Gujarat 382428 (India)

    2013-07-15

    In a simple magnetized toroidal plasma, fluctuation induced poloidal flux is found to be significant in magnitude. The probability distribution function of the fluctuation induced poloidal flux is observed to be strongly non-Gaussian in nature; however, in some cases, the distribution shows good agreement with the analytical form [Carreras et al., Phys. Plasmas 3, 2664 (1996)], assuming a coupling between the near Gaussian density and poloidal velocity fluctuations. The observed non-Gaussian nature of the fluctuation induced poloidal flux and other plasma parameters such as density and fluctuating poloidal velocity in this device is due to intermittent and bursty nature of poloidal transport. In the simple magnetized torus used here, such an intermittent fluctuation induced poloidal flux is found to play a crucial role in generating the poloidal flow.

  19. Quadratic fluctuation-dissipation theorem for multilayer plasmas

    SciTech Connect (OSTI)

    Golden, K.I. [Department of Mathematics and Statistics, University of Vermont, Burlington, Vermont 05401-1455 (United States)] [Department of Mathematics and Statistics, University of Vermont, Burlington, Vermont 05401-1455 (United States)

    1999-01-01

    The author establishes the dynamical and static quadratic fluctuation-dissipation theorems (QFDTs) for multilayer classical one-component plasmas in the absence of external magnetic fields. Areal densities and spacings between layers need not be equal. The static QFDT is used to derive the lowest-order (in coupling parameter) Mayer cluster expansion for the layer-space matrix elements of the equilibrium three-point correlation function. {copyright} {ital 1999} {ital The American Physical Society}

  20. Measurements of plasma bremsstrahlung and plasma energy density produced by electron cyclotron resonance ion source plasmas

    E-Print Network [OSTI]

    Noland, Jonathan David

    2011-01-01

    of x-ray power and plasma energy density with microwaveof diamagnetic loop used for plasma energy density mea-the average electron energy and density. During the slowly

  1. Analytic model for coaxial helicity injection in tokamak plasmas

    SciTech Connect (OSTI)

    Weening, R. H. [Department of Radiologic Sciences, Thomas Jefferson University, 130 S. 9th Street, Philadelphia, Pennsylvania 19107-5233 (United States)

    2011-12-15

    Using a partial differential equation for the time evolution of the mean-field poloidal magnetic flux that incorporates resistivity {eta} and hyper-resistivity {Lambda} terms, an exact analytic solution is obtained for steady-state coaxial helicity injection (CHI) in force-free large aspect ratio tokamaks. The analytic mean-field Ohm's law model allows for calculation of the tokamak CHI current drive efficiency and the plasma inductances at arbitrary levels of magnetic fluctuations, or dynamo activity. The results of the mean-field model suggest that CHI approaching Ohmic efficiency is only possible in tokamaks when the size of the effective current drive boundary layer, {delta}{identical_to}({Lambda}/{eta}){sup 1/2}, becomes greater than half the size of the plasma, {delta}>a/2, with a the plasma minor radius. The electron thermal diffusivity due to magnetic fluctuation induced transport is obtained from the expression {chi}{sub e}={Lambda}/{mu}{sub 0}d{sub e}{sup 2}, with {mu}{sub 0} the permeability of free space and d{sub e} the electron skin depth, which for typical tokamak fusion plasma parameters is on the order of a millimeter. Thus, the ratio of the energy confinement time to the resistive diffusion time in a tokamak plasma driven by steady-state CHI approaching Ohmic efficiency is shown to be constrained by the relation {tau}{sub E}/{tau}{sub {eta}}<(d{sub e}/a){sup 2}{approx_equal}10{sup -6}. The mean-field model suggests that steady-state CHI can be viewed most simply as a boundary layer of stochastically wandering magnetic field lines.

  2. Control of plasma process by use of harmonic frequency components of voltage and current

    DOE Patents [OSTI]

    Miller, Paul A. (Albuquerque, NM); Kamon, Mattan (Cambridge, MA)

    1994-01-01

    The present invention provides for a technique for taking advantage of the intrinsic electrical non-linearity of processing plasmas to add additional control variables that affect process performance. The technique provides for the adjustment of the electrical coupling circuitry, as well as the electrical excitation level, in response to measurements of the reactor voltage and current and to use that capability to modify the plasma characteristics to obtain the desired performance.

  3. An evaluation of inductance loop detector lead length and optimal speed trap distance 

    E-Print Network [OSTI]

    Hamm, Robert Alan

    1994-01-01

    component of freeway management systems is the inductance loop detector. This research effort evaluated the use of inductance loop detectors in a freeway management situation to determine maximum permissible lead lengths and an optimal speed trap distance...

  4. Specificity of Phenolic Glycoside Induction in Willow Seedlings (Salix sericea) in Response to Herbivory

    E-Print Network [OSTI]

    Orians, Colin

    Specificity of Phenolic Glycoside Induction in Willow Seedlings (Salix sericea) in Response Salix sericea (Marsh.) (Salicaceae) seedlings were used to investigate phyto- chemical induction . Specificity of elicitation . Salix . Plagiodera versicolora . Calligrapha multipunctata bigsbyana . Phenolic

  5. Sealing coupling. [LMFBR

    DOE Patents [OSTI]

    Pardini, J.A.; Brubaker, R.C.; Rusnak, J.J.

    1982-09-20

    Disclosed is a remotely operable releasable sealing coupling which provides fluid-tight joinder of upper and a lower conduit sections. Each conduit section has a concave conical sealing surface adjacent its end portion. A tubular sleeve having convex spherical ends is inserted between the conduit ends to form line contact with the concave conical end portions. An inwardly projecting lip located at one end of the sleeve cooperates with a retaining collar formed on the upper pipe end to provide swivel capture for the sleeve. The upper conduit section also includes a tapered lower end portion which engages the inside surface of the sleeve to limit misalignment of the connected conduit sections.

  6. FE ABUNDANCE IN SEMARKONA AND SAHARA 99555 Haolan Tang1,2

    E-Print Network [OSTI]

    as evidence that a supernova exploded in the vicinity of the birthplace of the Sun. However, our previous multi-collector inductively coupled plasma mass spectrometry (MC-ICPMS) measurements of a wide range multi-collector inductively coupled plasma mass spectrometry (MC-ICPMS), Tang & Dauphas (2012) found

  7. SLIM, Short-pulse Technology for High Gradient Induction Accelerators

    SciTech Connect (OSTI)

    Arntz, Floyd; Kardo-Sysoev, A.; Krasnykh, A.; /SLAC

    2008-12-16

    A novel short-pulse concept (SLIM) suited to a new generation of a high gradient induction particle accelerators is described herein. It applies advanced solid state semiconductor technology and modern microfabrication techniques to a coreless induction method of charged particle acceleration first proven on a macro scale in the 1960's. Because this approach avoids use of magnetic materials there is the prospect of such an accelerator working efficiently with accelerating pulses in the nanosecond range and, potentially, at megahertz pulse rates. The principal accelerator section is envisioned as a stack of coreless induction cells, the only active element within each being a single, extremely fast (subnanosecond) solid state opening switch: a Drift Step Recovery Diode (DSRD). Each coreless induction cell incorporates an electromagnetic pulse compressor in which inductive energy developed within a transmission-line feed structure over a period of tens of nanoseconds is diverted to the acceleration of the passing charge packet for a few nanoseconds by the abrupt opening of the DSRD switch. The duration of this accelerating output pulse--typically two-to-four nanoseconds--is precisely determined by a microfabricated pulse forming line connected to the cell. Because the accelerating pulse is only nanoseconds in duration, longitudinal accelerating gradients approaching 100 MeV per meter are believed to be achievable without inciting breakdown. Further benefits of this approach are that, (1) only a low voltage power supply is required to produce the high accelerating gradient, and, (2) since the DSRD switch is normally closed, voltage stress is limited to a few nanoseconds per period, hence the susceptibility to hostile environment conditions such as ionizing radiation, mismatch (e.g. in medical applications the peak beam current may be low), strong electromagnetic noise levels, etc is expected to be minimal. Finally, we observe the SLIM concept is not limited to linac applications; for instance, it could be employed to both accelerate the beam and to stabilize the superbunch mode of operation in circular track machines.

  8. Ferrite-Cored Solenoidal Induction Coil Sensor for BUD (MM-1667)

    E-Print Network [OSTI]

    Morrison, F.

    2012-01-01

    Research and Development Program Project MM-1667.INDUCTION COIL SENSOR FOR BUD (MM-1667) Frank Morrison 1 ,

  9. Electrical Engineering Department Los Angeles, California 90095-1594

    E-Print Network [OSTI]

    Chen, Francis F.

    ) plasmas: anomalous skin depth in inductively coupled plasmas (ICPs), transport by fluctuations in helicon is a spiral coil shaped like a stove-top heating element and placed on the dielectric top cover of a vacuum

  10. Fusion programs in applied plasma physics

    SciTech Connect (OSTI)

    Not Available

    1992-02-01

    The objectives of the theoretical science program are: To support the interpretation of present experiments and predict the outcome of future planned experiments; to improve on existing models and codes and validate against experimental results; and to conduct theoretical physics development of advanced concepts with applications for DIII-D and future devices. Major accomplishments in FY91 include the corroboration between theory and experiment on MHD behavior in the second stable regime of operation on DIII-D, and the frequency and mode structure of toroidal Alfven eigenmodes in high beta, shaped plasmas. We have made significant advances in the development of the gyro-Landau fluid approach to turbulence simulation which more accurately models kinetic drive and damping mechanisms. Several theoretical models to explain the bifurcation phenomenon in L- to H-mode transition were proposed providing the theoretical basis for future experimental verification. The capabilities of new rf codes have been upgraded in response to the expanding needs of the rf experiments. Codes are being employed to plan for a fully non-inductive current drive experiment in a high beta, enhanced confinement regime. GA's experimental effort in Applied Physics encompasses two advanced diagnostics essential for the operation of future fusion experiments: Alpha particle diagnostic, and current and density profile diagnostics. This paper discusses research in all these topics.

  11. SCOTT CAMPBELL and JAMES FRANKLIN RANDOMNESS AND THE JUSTIFICATION OF INDUCTION

    E-Print Network [OSTI]

    Franklin, James

    Stove defended and improved upon Williams' argument in The Rational- ity of Induction (1986). We call this proposed solution of induction the `Williams-Stove sampling thesis'. There has been no lack of objectionsSCOTT CAMPBELL and JAMES FRANKLIN RANDOMNESS AND THE JUSTIFICATION OF INDUCTION 1. INTRODUCTION

  12. Isentropic expansion of copper plasma in Mbar pressure range at “Luch” laser facility

    SciTech Connect (OSTI)

    Bel'kov, S. A.; Derkach, V. N.; Garanin, S. G.; Mitrofanov, E. I.; Voronich, I. N.; Fortov, V. E.; Levashov, P. R.; Minakov, D. V.

    2014-01-21

    We present experimental results on thermodynamic properties of dense copper plasma in Mbar pressure range. The laser facility “Luch” with laser intensity 10{sup 14}?W/cm{sup 2} is used to compress copper up to ?8?Mbar by a strong shock wave; subsequent expansion of copper plasma into Al, Ti, Sn allows us to obtain release isentropes of copper by the impedance–matching method. A theoretical analysis and quantum simulations show that in our experiments strongly coupled quantum plasma is generated.

  13. Relation between Lyapunov Exponent and Dielectric Response Function in Dilute One Component Plasmas

    SciTech Connect (OSTI)

    Ueshima, Y.; Nishihara, K. [Institute of Laser Engineering, Osaka University, Suita, Osaka 565 (Japan)] [Institute of Laser Engineering, Osaka University, Suita, Osaka 565 (Japan); Barnett, D.M.; Tajima, T. [Department of Physics and Institute of Fusion Studies, University of Texas at Austin, Austin, Texas 78712 (United States)] [Department of Physics and Institute of Fusion Studies, University of Texas at Austin, Austin, Texas 78712 (United States); Furukawa, H. [Institute for Laser Technology, Suita, Osaka 565 (Japan)] [Institute for Laser Technology, Suita, Osaka 565 (Japan)

    1997-09-01

    An analytical model is developed for the N -body largest Lyapunov exponent in the dilute plasma, and it is shown that the Lyapunov exponent relates to the dielectric response function. The relation provides a bridge between microscopic mechanical and macroscopic statistical quantities and it is expected to also be applicable for a weakly nonequilibrium system. In thermal equilibrium, the model shows that the Lyapunov exponent of dilute one component plasmas is of the same order as the plasma frequency and independent of the Coulomb coupling constant. These results agree fairly well with three dimensional particle simulations. {copyright} {ital 1997} {ital The American Physical Society}

  14. Rare-earth plasma extreme ultraviolet sources at 6.5-6.7 nm

    SciTech Connect (OSTI)

    Otsuka, Takamitsu; Higashiguchi, Takeshi; Yugami, Noboru; Yatagai, Toyohiko [Department of Advanced Interdisciplinary Sciences, Center for Optical Research and Education (CORE), Utsunomiya University, Yoto 7-1-2, Utsunomiya, Tochigi 321-8585 (Japan); Kilbane, Deirdre; White, John; Dunne, Padraig; O'Sullivan, Gerry [School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland); Jiang, Weihua [Department of Electrical Engineering, Nagaoka University of Technology, Kami-tomiokamachi 1603-1, Nagaoka, Niigata 940-2188 (Japan); Endo, Akira [Forschungszentrum Dresden, Bautzner Landstrs. 400, D-01328 Dresden (Germany)

    2010-09-13

    We have demonstrated a laser-produced plasma extreme ultraviolet source operating in the 6.5-6.7 nm region based on rare-earth targets of Gd and Tb coupled with a Mo/B{sub 4}C multilayer mirror. Multiply charged ions produce strong resonance emission lines, which combine to yield an intense unresolved transition array. The spectra of these resonant lines around 6.7 nm (in-band: 6.7 nm {+-}1%) suggest that the in-band emission increases with increased plasma volume by suppressing the plasma hydrodynamic expansion loss at an electron temperature of about 50 eV, resulting in maximized emission.

  15. Influence of ponderomotive force on the microwave and plasma interaction in an elliptical waveguide

    SciTech Connect (OSTI)

    Abdoli-Arani, A., E-mail: abdoliabbas@kashanu.ac.ir [Department of Photonics, Faculty of Physics, University of Kashan, Kashan, Islamic Republic of Iran (Iran, Islamic Republic of)

    2014-02-15

    The interaction effect of a high-power microwave with the plasma in an elliptical waveguide taking into account the ponderomotive force is presented. Here, we assume the fundamental mode that propagates in an evacuated elliptical waveguide and encounters a plasma, which is filled in another elliptical waveguide of the same size. Here, we consider a balance between the effects of ponderomotive force and the electron pressure and consider the plasma effect through its dielectric permittivity because the electron density distribution of the plasma is modified. The propagation of the mode is described by two nonlinear coupled differential equations obtained using the Maxwell's equations. These equations are solved numerically using fourth order Runge-Kutta method for the field amplitude of the microwave in the waveguide considering the waveguide to be made up of a perfect conductor and filled with homogeneous plasma density distribution. The effects of the electron temperature, the microwave filed, and the frequency on the perturbed density profile are studied.

  16. Regulation of Solar WindMagnetosphere Coupling by Ionospheric Outflows William Lotko, PI for Dartmouth College

    E-Print Network [OSTI]

    Lotko, William

    potential are also reduced, as is the flux of outflowing ionospheric ions, access of solar wind plasmaRegulation of Solar Wind­Magnetosphere Coupling by Ionospheric Outflows William Lotko, PI blunted as shown in the figure 2, which compares proton densities at 1634 UT in global simulations

  17. Princeton Plasma Physics Laboratory:

    SciTech Connect (OSTI)

    Phillips, C.A.

    1986-01-01

    This paper discusses progress on experiments at the Princeton Plasma Physics Laboratory. The projects and areas discussed are: Principal Parameters Achieved in Experimental Devices, Tokamak Fusion Test Reactor, Princeton Large Torus, Princeton Beta Experiment, S-1 Spheromak, Current-Drive Experiment, X-ray Laser Studies, Theoretical Division, Tokamak Modeling, Spacecraft Glow Experiment, Compact Ignition Tokamak, Engineering Department, Project Planning and Safety Office, Quality Assurance and Reliability, and Administrative Operations.

  18. Black hole temperature: Minimal coupling vs conformal coupling

    SciTech Connect (OSTI)

    Fazel, Mohamadreza; Mirza, Behrouz; Mansoori, Seyed Ali Hosseini

    2014-05-15

    In this article, we discuss the propagation of scalar fields in conformally transformed spacetimes with either minimal or conformal coupling. The conformally coupled equation of motion is transformed into a one-dimensional Schrödinger-like equation with an invariant potential under conformal transformation. In a second stage, we argue that calculations based on conformal coupling yield the same Hawking temperature as those based on minimal coupling. Finally, it is conjectured that the quasi normal modes of black holes are invariant under conformal transformation.

  19. Nonminimally coupled hybrid inflation

    SciTech Connect (OSTI)

    Koh, Seoktae [Center for Quantum Spacetime, Sogang University, Shinsu-dong 1, Mapo-gu, 121-742, Seoul (Korea, Republic of); Minamitsuji, Masato [Department of Physics, Graduate School of Science and Technology, Kwansei Gakuin University, Sanda 669-1337 (Japan)

    2011-02-15

    We discuss the hybrid inflation model where the inflaton field is nonminimally coupled to gravity. In the Jordan frame, the potential contains {phi}{sup 4} term as well as terms in the original hybrid inflation model. In our model, inflation can be classified into the type (I) and the type (II). In the type (I), inflation is terminated by the tachyonic instability of the waterfall field, while in the type (II) by the violation of slow-roll conditions. In our model, the reheating takes place only at the true minimum and even in the case (II) finally the tachyonic instability occurs after the termination of inflation. For a negative nonminimal coupling, inflation takes place in the vacuum-dominated region, in the large field region, or near the local minimum/maximum. Inflation in the vacuum-dominated region becomes either the type (I) or (II), resulting in a blue or red spectrum of the curvature perturbations, respectively. Inflation around the local maximum can be either the type (I) or the type (II), which results in the red spectrum of the curvature perturbations, while around the local minimum it must be the type (I), which results in the blue spectrum. In the large field region, to terminate inflation, potential in the Einstein frame must be positively tilted, always resulting in the red spectrum. We then numerically solve the equations of motion to investigate the whole dynamics of inflaton and confirm that the spectrum of curvature perturbations changes from red to blue ones as scales become smaller.

  20. PLASMA PHYSICS AND FUSION TECHNOLOGY; 79 ASTROPHYSICS, COSMOLOGY...

    Office of Scientific and Technical Information (OSTI)

    KINETICS; PHYSICS; PLASMA; PLASMA WAVES; PROCESSING; PROPULSION; SATELLITES; SHIELDING; SOLAR SYSTEM; THERMONUCLEAR REACTORS; UNIVERSE This introduction will define the plasma...