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Sample records for plasma source configuration

  1. Magnetosphere of Uranus: plasma sources, convection, and field configuration

    International Nuclear Information System (INIS)

    Voigt, G.; Hill, T.W.; Dessler, A.J.

    1983-01-01

    At the time of the Voyager 2 flyby of Uranus, the planetary rotational axis will be roughly antiparallel to the solar wind flow. If Uranus has a magnetic dipole moment that is approximately aligned with its spin axis, and if the heliospheric shock has not been encountered, we will have the rare opportunity to observe a ''pole-on'' magnetosphere as discussed qualitatively by Siscoe. Qualitative arguments based on analogy with Earth, Jupiter, and Saturn suggest that the magnetosphere of Uranus may lack a source of plasma adequate to produce significant internal currents, internal convection, and associated effects. In order to provide a test of this hypothesis with the forthcoming Voyager measurements, we have constructed a class of approximately self-consistent quantitative magnetohydrostatic equilibrium configurations for a pole-on magnetosphere with variable plasma pressure parameters. Given a few simplifying assumptions, the geometries of the magnetic field and of the tail current sheet can be computed for a given distribution of trapped plasma pressure. The configurations have a single funnel-shaped polar cusp that points directly into the solar wind and a cylindrical tail plasma sheet whose currents close within the tail rather than on the tail magnetopause, and whose length depends on the rate of decrease of thermal plasma pressure down the tail. Interconnection between magnetospheric and interplanetary fields results in a highly asymmetric tail-field configuration. These features were predicted qualtitatively by Siscoe; the quantitative models presented here may be useful in the interpretation of Voyager encounter results

  2. Plasma injection from the independent SHF-source in the open configuration 2. Magnetic fields of magnetic mirror configurations

    International Nuclear Information System (INIS)

    Beriya, Z.R.; Gogashvili, G.E.; Nanobashvili, S.I.

    1992-01-01

    The investigation was aimed at studying the characteristics and properties of plasma injected from independent stationary SHF source into an open magnetic trap of mirror geometry within a wide range of change in the experimental conditions. The investigations were primarily based on measurements of the distribution of charged particles in a plasma along the trap and on the dependence of the concentration on plasma production conditions in a SHF source. It is shown that the aggregate of the experimental data enables a conclusion that independent of SHF plasma can be succesfully used for filling on open magnetic trap of mirror configuration with plasma

  3. Configuration studies of LHD plasmas

    International Nuclear Information System (INIS)

    Okamoto, M.

    1997-01-01

    Configuration studies are performed on the plasmas of The Large Helical Device (LHD), the construction of which is almost completed at the National Institute for Fusion Science. The LHD has flexibility as an experimental device and can have various configurations by changing the poloidal magnetic fields, the pitch of the helical coils (pitch parameter), and the ratio of currents flowing in the two helical coils. Characteristics of the plasma are investigated for the standard configuration, the change in the pitch parameter, and the helical axis configuration

  4. Configuration studies of LHD plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Okamoto, Masao

    1997-03-01

    Configuration studies are performed on the plasmas of The Large Helical Device (LHD), the construction of which is almost completed at the National Institute for Fusion Science. The LHD has flexibility as an experimental device and can have various configurations by changing the poloidal magnetic fields, the pitch of the helical coils (pitch parameter), and the ratio of currents flowing in the two helical coils. Characteristics of the plasma are investigated for the standard configuration, the change in the pitch parameter, and the helical axis configuration. (author)

  5. Variable configuration plasmas in TCV

    International Nuclear Information System (INIS)

    Lister, J.B.; Hofmann, F.; Anton, M.

    1994-01-01

    During its first year of operation, TCV has achieved a wide variety of plasma shapes, limited and diverted, attaining 810 kA plasma current and elongation over 2.0. Ohmic H-Modes have been regularly produced, with a maximum confinement time of 80 msec and maximum normalised β N of 1.9. The conditions for the H-Mode transition differ from other experiments. The transitions from ELM-free to ELMy H-Modes and back have been selectively triggered for configurations close to a Double-Null. (author) 3 figs., 5 refs

  6. Variable configuration plasmas in TCV

    International Nuclear Information System (INIS)

    Lister, J.B.; Hofmann, F.; Anton, M.

    1995-01-01

    During its first year of operation, TCV has achieved a wide variety of plasma shapes, limited and diverted, attaining 810 kA plasma current and elongation over 2.0. Ohmic H modes have been regularly produced, with a maximum confinement time of 80 ms and a maximum normalized β N of 1.9. The conditions for the H mode transition differ from other experiments. The transitions from ELM free to ELMy H modes and back have been selectively triggered for configurations close to a double-null. (author). 5 refs, 3 figs

  7. Comparison of hollow cathode discharge plasma configurations

    International Nuclear Information System (INIS)

    Farnell, Casey C; Farnell, Cody C; Williams, John D

    2011-01-01

    Hollow cathodes used in plasma contactor and electric propulsion devices provide electrons for sustaining plasma discharges and enabling plasma bridge neutralization. Life tests show erosion on hollow cathodes exposed to the plasma environment produced in the region downstream of these devices. To explain the observed erosion, plasma flow field measurements are presented for hollow cathode generated plasmas using both directly immersed probes and remotely located plasma diagnostics. Measurements on two cathode discharge configurations are presented: (1) an open, no magnetic field configuration and (2) a setup simulating the discharge chamber environment of an ion thruster. In the open cathode configuration, large amplitude plasma potential oscillations, ranging from 20 to 85 V within a 34 V discharge, were observed using a fast response emissive probe. These oscillations were observed over a dc potential profile that included a well-defined potential hill structure. A remotely located electrostatic analyzer (ESA) was used to measure the energy of ions produced within the plasma, and energies were detected that met, and in some cases exceeded, the peak oscillatory plasma potentials detected by the emissive probe. In the ion thruster discharge chamber configuration, plasma potentials from the emissive probe again agreed with ion energies recorded by the remotely located ESA; however, much lower ion energies were detected compared with the open configuration. A simplified ion-transit model that uses temporal and spatial plasma property measurements is presented and used to predict far-field plasma streaming properties. Comparisons between the model and remote measurements are presented.

  8. Experimental study of a RF plasma source with helicon configuration in the mix Ar/H_2. Application to the chemical etching of carbon materials surfaces in the framework of the plasma-wall interactions studies of ITER's divertor

    International Nuclear Information System (INIS)

    Bieber, T.

    2012-01-01

    The issue of the interaction wall-plasma is important in thermonuclear devices. The purpose of this work is to design a very low pressure atomic plasma source in order to study chemical etching of carbon surfaces in the same conditions as edge plasma in tokamaks. The experimental work has consisted in 2 stages: first, the characterisation of the new helicon configuration reactor developed for this research and secondly the atomic hydrogen source used for the chemical etching. The first chapter recalls what thermonuclear fusion is. The helicon configuration reactor as well as its diagnostics (optical emission spectroscopy, laser induced fluorescence - LIF, and Langmuir probe) are described in the second chapter. The third chapter deals with the different coupling modes (RF power and plasma) identified in pure argon plasmas and how they are obtained by setting experimental parameters such as injected RF power, magnetic fields or pressure. The fourth chapter is dedicated to the study of the difference in behavior between the electronic density and the relative density of metastable Ar"+ ions. The last chapter presents the results in terms of mass losses of the carbon material surfaces obtained with the atomic hydrogen source. (A.C.)

  9. Magnetic Configuration Control of ITER Plasmas

    International Nuclear Information System (INIS)

    Albanese, R.; Artaserse, G.; Mattei, M.; Ambrosino, G.; Crisanti, F.; Tommasi, G. de; Fresa, R.; Portone, A.; Sartori, F.; Villone, F.

    2006-01-01

    The aim of this paper is to review the capability of the ITER Poloidal Field (PF) system of controlling the broad range of plasma configurations presently forecasted during ITER operation. The attention is focused on the axi-symmetric aspects of plasma magnetic configuration control since they pose the greatest challenges in terms of control power and they have the largest impact on machine capital cost. The paper is broadly divided in two main sections devoted, respectively, to open loop (feed-forward) and closed loop (feedback) control. In the first part of the study the PF system is assessed with respect to the initiation, ramp-up, sustained burn, ramp-down phases of the main plasma inductive scenario. The limiter-to-divertor configuration transition phase is considered in detail with the aim of assessing the PF capability to form an X-point at the lowest possible current and, therefore, to relax the thermal load on the limiter surfaces. Moreover, during the sustained burn it is important to control plasmas with a broad range of current density profiles. In the second part of the study the plasma vertical feedback control requirements are assessed in details, in particular for the high elongation configurations achievable during the early limiter-to-X point transition phase. Non-rigid plasma displacement models are used to assess the control system voltage and current requirements of different radial field control circuits obtained, for example, by connecting the outermost PF coils, some CS coils, coils sub-sections etc. At last, the main 3D effects of the vessel ports are modeled and their impact of vertical stabilization evaluated. (author)

  10. Magnetic configuration control of ITER plasmas

    International Nuclear Information System (INIS)

    Albanese, R.; Mattei, M.; Portone, A.; Ambrosino, G.; Artaserse, G.; Crisanti, F.; De Tommasi, G.; Fresa, R.; Sartori, F.; Villone, F.

    2007-01-01

    The aim of this paper is to present some new tools used to review the capability of the ITER Poloidal Field (PF) system in controlling the broad range of plasma configurations presently forecasted during ITER operation. The attention is focused on the axi-symmetric aspects of plasma magnetic configuration control since they pose the greatest challenges in terms of control power and they have the largest impact on machine capital cost. Some preliminary results obtained during ongoing activities in collaboration between ENEA/CREATE and EFDA are presented. The paper is divided in two main parts devoted, respectively, to the presentation of a procedure for the PF current optimisation during the scenario, and of a software environment for the study of the PF system capabilities using the plasma linearized response. The proposed PF current optimisation procedure is then used to assess Scenario 2 design, also taking into account the presence of axisymmetric eddy currents and possible variations of poloidal beta and internal inductance. The numerical linear model based tool derived from the JET oriented eXtreme Shape Controller (XSC) tools is finally used to obtain results on the strike point sweeping in ITER

  11. FAST Plasma Scenarios and Equilibrium Configurations

    International Nuclear Information System (INIS)

    Calabro, G.; Crisanti, F.; Ramogida, G.; Cardinali, A.; Cucchiaro, A.; Maddaluno, G.; Pizzuto, A.; Pericoli Ridolfini, V.; Tuccillo, A.A.; Zonca, F.; Albanese, R.; Granucci, G.; Nowak, S.

    2008-01-01

    In this paper we present the Fusion Advanced Studies Torus (FAST) plasma scenarios and equilibrium configurations, designed to reproduce the ITER ones (with scaled plasma current) and suitable to fulfil plasma conditions for integrated studies of burning plasma physics, Plasma Wall interaction, ITER relevant operation problems and Steady State scenarios. The attention is focused on FAST flexibility in terms of both performance and physics that can be investigated: operations are foreseen at a wide range of parameters from high performance H-Mode (toroidal field, B T , up to 8.5 T; plasma current, I P , up to 8 MA) to advanced tokamak (AT) operation (I P =3 MA) as well as full non inductive current scenario (I P =2 MA). The coupled heating power is provided with 30MW delivered by an Ion Cyclotron Resonance Heating (ICRH) system (30-90MHz), 6 MW by a Lower Hybrid (LH) system (3.7 or 5 GHz) for the long pulse AT scenario, 4 MW by an Electron Cyclotron Resonant Heating (ECRH) system (170 GHz-B T =6T) for MHD and electron heating localized control and, eventually, with 10 MW by a Negative Ion Beam (NNBI), which the ports are designed to accommodate. In the reference H-mode scenario FAST preserves (with respect to ITER) fast ions induced as well as turbulence fluctuation spectra, thus, addressing the cross-scale couplings issue of micro- to meso-scale physics. The noninductive scenario at I P =2MA is obtained with 60-70 % of bootstrap and the remaining by LHCD. Predictive simulations of the H-mode scenarios described above have been performed by means of JETTO code, using a semi-empirical mixed Bohm/gyro-Bohm transport model. Plasma position and Shape Control studies are also presented for the reference scenario

  12. TWRS configuration management requirement source document

    International Nuclear Information System (INIS)

    Vann, J.M.

    1997-01-01

    The TWRS Configuration Management (CM) Requirement Source document prescribes CM as a basic product life-cycle function by which work and activities are conducted or accomplished. This document serves as the requirements basis for the TWRS CM program. The objective of the TWRS CM program is to establish consistency among requirements, physical/functional configuration, information, and documentation for TWRS and TWRS products, and to maintain this consistency throughout the life-cycle of TWRS and the product, particularly as changes are being made

  13. Pulsed Plasma Electron Sources

    Science.gov (United States)

    Krasik, Yakov

    2008-11-01

    Pulsed (˜10-7 s) electron beams with high current density (>10^2 A/cm^2) are generated in diodes with electric field of E > 10^6 V/cm. The source of electrons in these diodes is explosive emission plasma, which limits pulse duration; in the case E Saveliev, J. Appl. Phys. 98, 093308 (2005). Ya. E. Krasik, A. Dunaevsky, and J. Felsteiner, Phys. Plasmas 8, 2466 (2001). D. Yarmolich, V. Vekselman, V. Tz. Gurovich, and Ya. E. Krasik, Phys. Rev. Lett. 100, 075004 (2008). J. Z. Gleizer, Y. Hadas and Ya. E. Krasik, Europhysics Lett. 82, 55001 (2008).

  14. Plasma source ion implantation

    International Nuclear Information System (INIS)

    Conrad, J.R.; Forest, C.

    1986-01-01

    The authors' technique allows the ion implantation to be performed directly within the ion source at higher currents without ion beam extraction and transport. The potential benefits include greatly increased production rates (factors of 10-1000) and the ability to implant non-planar targets without rastering or shadowing. The technique eliminates the ion extractor grid set, beam raster equipment, drift space and target manipulator equipment. The target to be implanted is placed directly within the plasma source and is biased to a large negative potential so that plasma ions gain energy as they accelerate through the potential drop across the sheath that forms at the plasma boundary. Because the sheath surrounds the target on all sides, all surfaces of the target are implanted without the necessity to raster the beam or to rotate the target. The authors have succeeded in implanting nitrogen ions in a silicon target to the depths and concentrations required for surface treatment of materials like stainless steel and titanium alloys. They have performed ESCA measurements of the penetration depth profile of a silicon target that was biased to 30 kV in a nitrogen discharge plasma. Nitrogen ions were implanted to a depth of 700A at a peak concentration of 30% atomic. The measured profile is quite similar to a previously obtained profile in titanium targets with conventional techniques

  15. Surface plasma source with saddle antenna radio frequency plasma generator.

    Science.gov (United States)

    Dudnikov, V; Johnson, R P; Murray, S; Pennisi, T; Piller, C; Santana, M; Stockli, M; Welton, R

    2012-02-01

    A prototype RF H(-) surface plasma source (SPS) with saddle (SA) RF antenna is developed which will provide better power efficiency for high pulsed and average current, higher brightness with longer lifetime and higher reliability. Several versions of new plasma generators with small AlN discharge chambers and different antennas and magnetic field configurations were tested in the plasma source test stand. A prototype SA SPS was installed in the Spallation Neutron Source (SNS) ion source test stand with a larger, normal-sized SNS AlN chamber that achieved unanalyzed peak currents of up to 67 mA with an apparent efficiency up to 1.6 mA∕kW. Control experiments with H(-) beam produced by SNS SPS with internal and external antennas were conducted. A new version of the RF triggering plasma gun has been designed. A saddle antenna SPS with water cooling is fabricated for high duty factor testing.

  16. Plasma antennas: dynamically configurable antennas for communications

    International Nuclear Information System (INIS)

    Borg, G.; Harris, J.

    1999-01-01

    In recent years, the rapid growth in both communications and radar systems has led to a concomitant growth in the possible applications and requirements of antennas. These new requirements include compactness and conformality, rapid reconfigurability for directionality and frequency agility. For military applications, antennas should also allow low absolute or out-of-band radar cross-section and facilitate low probability of intercept communications. Investigations have recently begun worldwide on the use of ionised gases or plasmas as the conducting medium in antennas that could satisfy these requirements. Such plasma antennas may even offer a viable alternative to metal in existing applications when overall technical requirements are considered. A recent patent for ground penetrating radar claims the invention of a plasma antenna for the transmission of pulses shorter than 100 ns in which it is claimed that current ringing is avoided and signal processing simplified compared with a metal antenna. A recent US ONR tender has been issued for the design and construction of a compact and rapidly reconfigurable antenna for dynamic signal reception over the frequency range 1 - 45 GHz based on plasma antennas. Recent basic physics experiments at ANU have demonstrated that plasma antennas can attain adequate efficiency, predictable radiation patterns and low base-band noise for HF and VHF communications. In this paper we describe the theory of the low frequency plasma antenna and present a few experimental results

  17. Simulations of a Plasma Thruster Utilizing the FRC Configuration

    Energy Technology Data Exchange (ETDEWEB)

    Rognlien, T. D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Cohen, B. I. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-10-10

    This report describes work performed by LLNL to model the behavior and performance of a reverse-field configuration (FRC) type of plasma device as a plasma thruster as summarized by Razin et al. [1], which also describes the MNX device at PPPL used to study this concept.

  18. Resistive instabilities in general toroidal plasma configurations

    International Nuclear Information System (INIS)

    Glasser, A.H.; Greene, J.M.; Johnson, J.L.

    1975-01-01

    Previous work by Johnson and Greene on resistive instabilities is extended to finite-pressure configurations. The Mercier criterion for the stability of the ideal magnetohydrodynamic interchange mode is rederived, the generalization of the earlier stability criterion for the resistive interchange mode is obtained, and a relation between the two is noted. Conditions for tearing mode instability are recovered with the growth rate scaling with the resistivity in a more complicated manner than eta 3 / 5 . Nyquist techniques are used to show that favorable average curvature can convert the tearing mode into an overstable mode and can often stabilize it

  19. Tearing instability in cylindrical plasma configuration

    International Nuclear Information System (INIS)

    Zelenyj, L.M.

    1979-01-01

    The effect of the neutral-layer cylindrical geometry on the development of the tearing instability has been investigated in detail. The increments of the instability for all the regimes have been found. The influence of cylindrical effects becomes manifesting itself at small, as compared to the layer characteristic thickness, distances from the axis, and, finally, the electron regime of the instability development transforms into an ion one. The results obtained are of interest for studying the plasma stability in the devices of the ''Astron'' type and in magnetospheres of cosmic objects

  20. Feedback control of plasma configuration in JT-60

    International Nuclear Information System (INIS)

    Ninomiya, Hiromasa; Kikuchi, Mitsuru; Yoshino, Ryuji; Hosogane, Nobuyuki; Kimura, Toyoaki; Kurihara, Kenichi; Takahashi, Minoru; Hayashi, Kazuo.

    1986-08-01

    Plasma current, plasma position (center of the outermost magnetic surface), decay index n index and width of the divertor throat are feedback controlled by using 5 kinds of poloidal field coils in JT-60. 5 control commands are calculated in a feedback control computer in each 1 msec. These feedback control functions are checked in ohmically heated plasma. The control characteristics of the plasma are well understood by the simplified control analysis and are consistent with the precise matrix transfer function analysis in the frequency domain and the simulation analysis which include the effects of eddy currents, delay time elements and mutual interactions between controllers. The usefulness of these analyses is experimentally confirmed. Each controlled variable is well feedback controlled to the command and the experimentally realized equilibrium configuration is checked by the well calibrated magnetic probes. Fast boundary identification code is used for the identification of the equilibrium and results are consistent with the precalculated plasma equilibria. By using this feedback control system of the plasma configuration and the equilibrium identification method, we have obtained the stable limiter and divertor configuration. The maximum parameters obtained during OH(I) experimental period are plasma current I p = 1.8 MA, the effective safety factor q eff e = 5.7 x 10 19 m -3 (Murakami parameter of 4.5) and the pulse length of 5 ∼ 10 sec. (author)

  1. Counter-facing plasma guns for efficient extreme ultra-violet plasma light source

    Science.gov (United States)

    Kuroda, Yusuke; Yamamoto, Akiko; Kuwabara, Hajime; Nakajima, Mitsuo; Kawamura, Tohru; Horioka, Kazuhiko

    2013-11-01

    A plasma focus system composed of a pair of counter-facing coaxial guns was proposed as a long-pulse and/or repetitive high energy density plasma source. We applied Li as the source of plasma for improvement of the conversion efficiency, the spectral purity, and the repetition capability. For operation of the system with ideal counter-facing plasma focus mode, we changed the system from simple coaxial geometry to a multi-channel configuration. We applied a laser trigger to make synchronous multi-channel discharges with low jitter. The results indicated that the configuration is promising to make a high energy density plasma with high spectral efficiency.

  2. Microwave interferometry of PEOS plasma sources

    International Nuclear Information System (INIS)

    Weber, B.V.; Commisso, R.J.; Goodrich, P.J.; Hinshelwood, D.D.; Neri, J.M.

    1988-01-01

    A 70 GHz microwave interferometer is used to measure the electron density for various configurations of sources used in plasma erosion opening switch (PEOS) experiments. The interferometer is a phase quadrature system, so the density can be measured as a function of time without ambiguity. Measurements have been made for carbon guns and flashboards driven by a .6 μF. 25 kV capacitor. The plasma density from a gun rises to its peak value in about 10 μs. Then decays in the next 40 μs. A metal screen placed between the gun and the microwave beam attenuates the plasma density by a factor greater than the geometrical transparency of the screen. Density measurements as a function of distance from the gun are analyzed to give the plasma spatial dependence, and the particle flux density and flow velocity are calculated from the continuity equation. Density values used to model previous PEOS experiments are comparable to the values measured here. The flashboard sources produce a denser, faster plasma that is more difficult to diagnose with the interferometer than the gun plasma because of refractive bending of the microwave beam. Reducing the plasma length reduces the refractive bending enough that some measurements are possible. Direct comparison with Gamble II PEOS experiments that used these flashboard sources may not be possible at this frequency because of refraction, but estimates based on measurements at larger distances give reasonable agreement with values used to model these experiments. Other measurements that will be presented include the effects of plasma flow against metal walls, effects of changing the driving current waveform, measurements made in actual experimental configurations and comparisons with Faraday cup and electric probe measurements

  3. Edge plasma control using an LID configuration on CHS

    Energy Technology Data Exchange (ETDEWEB)

    Masuzaki, S.; Komori, A.; Morisaki, T. [National Inst. for Fusion Science, Oroshi, Toki (Japan)] [and others

    1997-07-01

    A Local Island Divertor (LID) has been proposed to enhance energy confinement through neutral particle control. For the case of the Large Helical Device (LHD), the separatrix of an m/n = 1/1 magnetic island, formed at the edge region, will be utilized as a divertor configuration. The divertor head is inserted in the island, and the island separatrix provides connection between the edge plasma region surrounding the core plasma and the back plate of the divertor head through the field lines. The particle flux and associated heat flux from the core plasma strike the back plate of the divertor head, and thus particle recycling is localized in this region. A pumping duct covers the divertor head to form a closed divertor system for efficient particle exhaust. The advantages of the LID are ease of hydrogen pumping because of the localized particle recycling and avoidance of the high heat load that would be localized on the leading edge of the divertor head. With efficient pumping, the neutral pressure in the edge plasma region will be reduced, and hence the edge plasma temperature will be higher, hopefully leading to a better core confinement region. A LID configuration experiment was done on the Compact Helical System (CHS) to confirm the effect of the LID. The typical effects of the LID configuration on the core plasma are reduction of the line averaged density to a half, and small or no reduction of the stored energy. In this contribution, the experimental results which were obtained in edge plasma control experiments with the LID configuration in the CHS are presented.

  4. Double plasma system with inductively coupled source plasma and quasi-quiescent target plasma

    International Nuclear Information System (INIS)

    Massi, M.; Maciel, H.S.

    1995-01-01

    Cold plasmas have successfully been used in the plasma-assisted material processing industry. An understanding of the physicochemical mechanisms involved in the plasma-surface interaction is needed for a proper description of deposition and etching processes at material surfaces. Since these mechanisms are dependent on the plasma properties, the development of diagnostic techniques is strongly desirable for determination of the plasma parameters as well as the characterization of the electromagnetic behaviour of the discharge. In this work a dual discharge chamber, was specially designed to study the deposition of thin films via plasma polymerization process. In the Pyrex chamber an inductively coupled plasma can be excited either in the diffuse low density E-mode or in the high density H-mode. This plasma diffuses into the cylindrical stainless steel chamber which is covered with permanent magnets to produce a multidipole magnetic field configuration at the surface. By that means a double plasma is established consisting of a RF source plasma coupled to a quasi-quiescent target plasma. The preliminary results presented here refer to measurements of the profiles of plasma parameters along the central axis of the double plasma apparatus. Additionally a spectrum analysis performed by means of a Rogowski coil probe immersed into the source plasma is also presented. The discharge is made in argon with pressure varying from 10 -2 to 1 torr, and the rf from 10 to 150 W

  5. Development of very large helicon plasma source

    International Nuclear Information System (INIS)

    Shinohara, Shunjiro; Tanikawa, Takao

    2004-01-01

    We have developed a very large volume, high-density helicon plasma source, 75 cm in diameter and 486 cm in axial length; full width at half maximum of the plasma density is up to ∼42 cm with good plasma uniformity along the z axis. By the use of a spiral antenna located just outside the end of the vacuum chamber through a quartz-glass window, plasma can be initiated with a very low value of radio frequency (rf) power ( 12 cm -3 is successfully produced with less than several hundred Watt; achieving excellent discharge efficiency. It is possible to control the radial density profile in this device by changing the magnetic field configurations near the antenna and/or the antenna radiation-field patterns

  6. Density effects on electronic configurations in dense plasmas

    Science.gov (United States)

    Faussurier, Gérald; Blancard, Christophe

    2018-02-01

    We present a quantum mechanical model to describe the density effects on electronic configurations inside a plasma environment. Two different approaches are given by starting from a quantum average-atom model. Illustrations are shown for an aluminum plasma in local thermodynamic equilibrium at solid density and at a temperature of 100 eV and in the thermodynamic conditions of a recent experiment designed to characterize the effects of the ionization potential depression treatment. Our approach compares well with experiment and is consistent in that case with the approach of Stewart and Pyatt to describe the ionization potential depression rather than with the method of Ecker and Kröll.

  7. Translation experiment of a plasma with field reversed configuration

    International Nuclear Information System (INIS)

    Tanjyo, Masayasu; Okada, Shigefumi; Ito, Yoshifumi; Kako, Masashi; Ohi, Shoichi

    1984-01-01

    Experiments to translate the FRC plasma from is formation area (pinch coil) into two kinds of metal vessels (magnetic flux conservers) with larger and smaller bore than that of the pinch coil have been carried out in OCT with an aim of improving the particle confinement time tau sub(N) by increasing xsub(s) (ratio of the plasma radius to that of the conducting wall). Demonstrated were successful translations of the plasma into both vessels. The xsub(s) of the translated plasma increased to 0.6 in the larger bore vessel and to 0.7 in the smaller one from 0.4 of the source plasma in the pinch coil. With the increase in xsub(s), tau sub(N) and also decay time of the trapped magnetic flux are extended from 15 - 20 μs of the source plasma to 50 - 80 μs. The tau sub(N) is found to have stronger dependence on xsub(s) than on rsub(s). During the translation phase, almost half of the total particle and the plasma energy are lost. The plasma volume is, therefore, about half of that expected from the analysis on the ideal translation process. It is also found that the translation process is nearly isothermal as is expected from the analysis. (author)

  8. Ion source with plasma cathode

    International Nuclear Information System (INIS)

    Yabe, E.

    1987-01-01

    A long lifetime ion source with plasma cathode has been developed for use in ion implantation. In this ion source, a plasma of a nonreactive working gas serves as a cathode in place of a thermionic tungsten filament used in the Freeman ion source. In an applied magnetic field, the plasma is convergent, i.e., filamentlike; in zero magnetic field, it turns divergent and spraylike. In the latter case, the plasma exhibits a remarkable ability when the working gas has an ionization potential larger than the feed gas. By any combination of a working gas of either argon or neon and a feed gas of AsF 5 or PF 5 , the lifetime of this ion source was found to be more than 90 h with an extraction voltage of 40 kV and the corresponding ion current density 20 mA/cm 2 . Mass spectrometry results show that this ion source has an ability of generating a considerable amount of As + and P + ions from AsF 5 and PF 5 , and hence will be useful for realizing a fully cryopumped ion implanter system. This ion source is also eminently suitable for use in oxygen ion production

  9. 21 CFR 640.60 - Source Plasma.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Source Plasma. 640.60 Section 640.60 Food and... ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Source Plasma § 640.60 Source Plasma. The proper name of the product shall be Source Plasma. The product is defined as the fluid portion of human blood...

  10. Study of MRI in stratified viscous plasma configuration

    Science.gov (United States)

    Carlevaro, Nakia; Montani, Giovanni; Renzi, Fabrizio

    2017-02-01

    We analyze the morphology of the magneto-rotational instability (MRI) for a stratified viscous plasma disk configuration in differential rotation, taking into account the so-called corotation theorem for the background profile. In order to select the intrinsic Alfvénic nature of MRI, we deal with an incompressible plasma and we adopt a formulation of the local perturbation analysis based on the use of the magnetic flux function as a dynamical variable. Our study outlines, as consequence of the corotation condition, a marked asymmetry of the MRI with respect to the equatorial plane, particularly evident in a complete damping of the instability over a positive critical height on the equatorial plane. We also emphasize how such a feature is already present (although less pronounced) even in the ideal case, restoring a dependence of the MRI on the stratified morphology of the gravitational field.

  11. HEAVY ION FUSION SCIENCE VIRTUAL NATIONAL LABORATORY 3nd QUARTER 2009 MILESTONE REPORT: Upgrade plasma source configuration and carry out initial experiments. Characterize improvements in focal spot beam intensity

    International Nuclear Information System (INIS)

    Lidia, S.; Anders, A.; Barnard, J.J.; Bieniosek, F.M.; Dorf, M.; Faltens, A.; Friedman, A.; Gilson, E.; Greenway, W.; Grote, D.; Jung, J.Y.; Katayanagi, T.; Logan, B.G.; Lee, C.W.; Leitner, M.; Ni, P.; Pekedis, A.; Regis, M. J.; Roy, P. K.; Seidl, P. A.; Waldron, W.

    2009-01-01

    Simulations suggest that the plasma density must exceed the beam density throughout the drift compression and focusing section in order to inhibit the space charge forces that would limit the spot size and beam intensity on the target. WDM experiments will therefore require plasma densities up to 10 14 /cm 3 , with the highest density in the last few centimeters before the target. This work was guided by the simulations performed for the FY09 Q1 milestone. This milestone has been met and we report results of modifications made to the NDCX beamline to improve the longitudinal and radial distribution of the neutralizing plasma in the region near the target plane. In Section 2, we review pertinent simulation results from the FY09 Q1 milestone. Section 3 describes the design, and beam measurements following installation, of a biased, self-supporting metal grid that produces neutralizing electrons from glancing interception of beam ions. Section 4 describes the design and initial testing of a compact Ferro-Electric Plasma Source (FEPS) that will remove the remaining 'exclusion zone' in the neutralizing plasma close to the target plane. Section 5 describes the modification of the beamline to decrease the gap between the FEPS section exit and the final focus solenoid (FFS). Section 6 presents a summary and conclusions.

  12. Improved planar radio frequency inductively coupled plasma configuration in plasma immersion ion implantation

    International Nuclear Information System (INIS)

    Tang, D.L.; Fu, R.K.Y.; Tian, X.B.; Chu, P.K.

    2003-01-01

    Plasmas with higher density and better uniformity are produced using an improved planar radio frequency (rf) inductively coupled plasma configuration in plasma immersion ion implantation (PIII). An axial magnetic field is produced by external electromagnetic coils outside the discharge chamber. The rf power can be effectively absorbed by the plasma in the vicinity of the electron gyrofrequency due to the enhanced resonant absorption of electromagnetic waves in the whistler wave range, which can propagate nearly along the magnetic field lines thus greatly increases the plasma density. The plasma is confined by a longitudinal multipolar cusp magnetic field made of permanent magnets outside the process chamber. It can improve the plasma uniformity without significantly affecting the ion density. The plasma density can be increased from 3x10 9 to 1x10 10 cm -3 employing an axial magnetic field of several Gauss at 1000 W rf power and 5x10 -4 Torr gas pressure. The nonuniformity of the plasma density is less than 10% and can be achieved in a process chamber with a diameter of 600 mm. Since the plasma generation and process chambers are separate, plasma extinction due to the plasma sheath touching the chamber wall in high-energy PIII can be avoided. Hence, low-pressure, high-energy, and high-uniformity ion implantation can be accomplished using this setup

  13. A Flexible Power Electronics Configuration for Coupling Renewable Energy Sources

    Directory of Open Access Journals (Sweden)

    Mattia Filippini

    2015-05-01

    Full Text Available A combination of series, parallel and multilevel power electronics has been investigated as a potential interface for two different types of renewable energy sources and in order to reach higher power levels. Renewable energy sources are typically dispersed in a territory, and sources, like wind and solar, allow small to medium-scale generation of electricity. The configuration investigated in this article aims at adapting the coupling solution to the specific generation characteristics of the renewable energy source to make it fit the electrical network. The configuration consists of a combination of three-phase multilevel converters and single-phase inverters, which are designed to provide flexibility, high power quality and high efficiency. A detailed analysis and simulation is performed to identify the properties in conjunction with the electrical grid requirements and the potential challenges encountered during operation. An optimized operation example of wind generation combined with solar PV generation is presented to exemplify the flexibility and benefits of the proposed configuration.

  14. Isodynamical (omnigenous) equilibrium in symmetrically confined plasma configurations

    International Nuclear Information System (INIS)

    Bernardin, M.P.; Moses, R.W.; Tataronis, J.A.

    1986-01-01

    Isodynamical or omnigenous equilibrium has the property that the magnitude of the magnetic field is constant on magnetic surfaces. It is shown that in plasma confinement configurations with one ignorable coordinate there are three possible classes of solutions, characterized by the properties of the curvature of the magnetic axis, the magnitude of the magnetic field on axis, and the closure of magnetic surfaces about the magnetic axis. Solutions belonging to class (i) have a straight magnetic axis, a finite field on axis, and closed magnetic surfaces. Solutions in class (ii) have a curved magnetic axis, closed magnetic surfaces, and a magnetic field that vanishes on axis. Finally, solutions in class (iii) have a curved magnetic axis, a finite magnetic field on axis, and open magnetic surfaces

  15. Counter-facing plasma guns for efficient extreme ultra-violet plasma light source

    Directory of Open Access Journals (Sweden)

    Kuroda Yusuke

    2013-11-01

    Full Text Available A plasma focus system composed of a pair of counter-facing coaxial guns was proposed as a long-pulse and/or repetitive high energy density plasma source. We applied Li as the source of plasma for improvement of the conversion efficiency, the spectral purity, and the repetition capability. For operation of the system with ideal counter-facing plasma focus mode, we changed the system from simple coaxial geometry to a multi-channel configuration. We applied a laser trigger to make synchronous multi-channel discharges with low jitter. The results indicated that the configuration is promising to make a high energy density plasma with high spectral efficiency.

  16. A new large-scale plasma source with plasma cathode

    International Nuclear Information System (INIS)

    Yamauchi, K.; Hirokawa, K.; Suzuki, H.; Satake, T.

    1996-01-01

    A new large-scale plasma source (200 mm diameter) with a plasma cathode has been investigated. The plasma has a good spatial uniformity, operates at low electron temperature, and is highly ionized under relatively low gas pressure of about 10 -4 Torr. The plasma source consists of a plasma chamber and a plasma cathode generator. The plasma chamber has an anode which is 200 mm in diameter, 150 mm in length, is made of 304 stainless steel, and acts as a plasma expansion cup. A filament-cathode-like plasma ''plasma cathode'' is placed on the central axis of this source. To improve the plasma spatial uniformity in the plasma chamber, a disk-shaped, floating electrode is placed between the plasma chamber and the plasma cathode. The 200 mm diameter plasma is measure by using Langmuir probes. As a result, the discharge voltage is relatively low (30-120 V), the plasma space potential is almost equal to the discharge voltage and can be easily controlled, the electron temperature is several electron volts, the plasma density is about 10 10 cm -3 , and the plasma density is about 10% variance in over a 100 mm diameter. (Author)

  17. Simulating Sources of Superstorm Plasmas

    Science.gov (United States)

    Fok, Mei-Ching

    2008-01-01

    We evaluated the contributions to magnetospheric pressure (ring current) of the solar wind, polar wind, auroral wind, and plasmaspheric wind, with the surprising result that the main phase pressure is dominated by plasmaspheric protons. We used global simulation fields from the LFM single fluid ideal MHD model. We embedded the Comprehensive Ring Current Model within it, driven by the LFM transpolar potential, and supplied with plasmas at its boundary including solar wind protons, polar wind protons, auroral wind O+, and plasmaspheric protons. We included auroral outflows and acceleration driven by the LFM ionospheric boundary condition, including parallel ion acceleration driven by upward currents. Our plasmasphere model runs within the CRCM and is driven by it. Ionospheric sources were treated using our Global Ion Kinetics code based on full equations of motion. This treatment neglects inertial loading and pressure exerted by the ionospheric plasmas, and will be superceded by multifluid simulations that include those effects. However, these simulations provide new insights into the respective role of ionospheric sources in storm-time magnetospheric dynamics.

  18. High density plasma heating in the Tokamak à configuration variable

    International Nuclear Information System (INIS)

    Curchod, L.

    2011-04-01

    The Tokamak à Configuration Variable (TCV) is a medium size magnetic confinement thermonuclear fusion experiment designed for the study of the plasma performances as a function of its shape. It is equipped with a high power and highly flexible electron cyclotron heating (ECH) and current drive (ECCD) system. Up to 3 MW of 2 nd harmonic EC power in ordinary (O 2 ) or extraordinary (X 2 ) polarization can be injected from TCV low-field side via six independently steerable launchers. In addition, up to 1.5 MW of 3 rd harmonic EC power (X 3 ) can be launched along the EC resonance from the top of TCV vacuum vessel. At high density, standard ECH and ECCD are prevented by the appearance of a cutoff layer screening the access to the EC resonance at the plasma center. As a consequence, less than 50% of TCV density operational domain is accessible to X 2 and X 3 ECH. The electron Bernstein waves (EBW) have been proposed to overcome this limitation. EBW is an electrostatic mode propagating beyond the plasma cutoff without upper density limit. Since it cannot propagate in vacuum, it has to be excited by mode conversion of EC waves in the plasma. Efficient electron Bernstein waves heating (EBH) and current drive (EBCD) were previously performed in several fusion devices, in particular in the W7-AS stellarator and in the MAST spherical tokamak. In TCV, the conditions for an efficient O-X-B mode conversion (i.e. a steep density gradient at the O 2 plasma cutoff) are met at the edge of high confinement (H-mode) plasmas characterized by the appearance of a pedestal in the electron temperature and density profiles. TCV experiments have demonstrated the first EBW coupling to overdense plasmas in a medium aspect-ratio tokamak via O-X-B mode conversion. This thesis work focuses on several aspects of ECH and EBH in low and high density plasmas. Firstly, the experimental optimum angles for the O-X-B mode conversion is successfully compared to the full-wave mode conversion calculation

  19. Physics and applications of micro-plasmas in dielectric barrier and hollow cathode configurations

    International Nuclear Information System (INIS)

    Boeuf, J. P.; Pitchford, L. C.

    2005-01-01

    Non-equilibrium or non-thermal plasmas operate at low gas temperatures and this property make these plasmas very attractive in a number of applications, from etching and deposition in the microelectronics industry to plasma displays and pollution control. However, although it is quite easy to generate a large volume non-equilibrium plasma at pressure on the order or below 100 Pa, this is more of a challenge around atmospheric pressure. Large area plasma sources operating at atmospheric pressure represent a very cost-effective solution for material processing, light sources and other applications, and a large research effort has been devoted to the development of such sources in the last ten years. Dielectric Barrier Discharges (DBDs), where one or both electrodes are covered with a dielectric layer are good candidates for atmospheric non-equilibrium plasma generation because of their ability to limit the current and power deposition. It is also much easier to control an atmospheric discharge in a small volume. Therefore an atmospheric plasma source often consists of a number of micro-discharges arranged in a way that depends on the application. Even in DBDs with large electrode areas, the plasma is generally not uniform and consists in a large number of micro-discharges or filaments. In this lecture we present a discussion of the physical properties of non-equilibrium plasmas generated in different configurations and operating at atmospheric pressure. This discussion is based on results from numerical models and simulations of Dielectric Barrier Discharges to Micro-Hollow Cathode Discharges. We then focus on specific applications such as surface DBDs for flow control. These discharges (which have some similarities with the surface micro-discharges used in Plasma Display Panels) are being studied for their ability to modify the properties of the boundary layer along airfoils and hence to control the transition between laminar and turbulent regimes. We will show how

  20. Ion acceleration in the plasma source sheath

    International Nuclear Information System (INIS)

    Birdsall, C.K.

    1986-01-01

    This note is a calculation of the potential drop for a planar plasma source, across the source sheath, into a uniform plasma region defined by vector E = 0 and/or perhaps ∂ 2 PHI/∂ x 2 = 0. The calculation complements that of Bohm who obtained the potential drop at the other end of a plasma, at a planar collector sheath. The result is a relation between the source ion flux and the source sheath potential drop and the accompanying ion acceleration. This planar source sheath ion acceleration mechanism (or that from a distributed source) can provide the pre-collector-sheath ion acceleration as found necessary by Bohm. 3 refs

  1. Large area ion and plasma beam sources

    Energy Technology Data Exchange (ETDEWEB)

    Waldorf, J. [IPT Ionen- und Plasmatech. GmbH, Kaiserslautern (Germany)

    1996-06-01

    In the past a number of ion beam sources utilizing different methods for plasma excitation have been developed. Nevertheless, a widespread use in industrial applications has not happened, since the sources were often not able to fulfill specific demands like: broad homogeneous ion beams, compatibility with reactive gases, low ion energies at high ion current densities or electrical neutrality of the beam. Our contribution wants to demonstrate technical capabilities of rf ion and plasma beam sources, which can overcome the above mentioned disadvantages. The physical principles and features of respective sources are presented. We report on effective low pressure plasma excitation by electron cyclotron wave resonance (ECWR) for the generation of dense homogeneous plasmas and the rf plasma beam extraction method for the generation of broad low energy plasma beams. Some applications like direct plasma beam deposition of a-C:H and ion beam assisted deposition of Al and Cu with tailored thin film properties are discussed. (orig.).

  2. Large area ion and plasma beam sources

    International Nuclear Information System (INIS)

    Waldorf, J.

    1996-01-01

    In the past a number of ion beam sources utilizing different methods for plasma excitation have been developed. Nevertheless, a widespread use in industrial applications has not happened, since the sources were often not able to fulfill specific demands like: broad homogeneous ion beams, compatibility with reactive gases, low ion energies at high ion current densities or electrical neutrality of the beam. Our contribution wants to demonstrate technical capabilities of rf ion and plasma beam sources, which can overcome the above mentioned disadvantages. The physical principles and features of respective sources are presented. We report on effective low pressure plasma excitation by electron cyclotron wave resonance (ECWR) for the generation of dense homogeneous plasmas and the rf plasma beam extraction method for the generation of broad low energy plasma beams. Some applications like direct plasma beam deposition of a-C:H and ion beam assisted deposition of Al and Cu with tailored thin film properties are discussed. (orig.)

  3. Honeycomblike large area LaB6 plasma source for Multi-Purpose Plasma facility

    International Nuclear Information System (INIS)

    Woo, Hyun-Jong; Chung, Kyu-Sun; You, Hyun-Jong; Lee, Myoung-Jae; Lho, Taihyeop; Choh, Kwon Kook; Yoon, Jung-Sik; Jung, Yong Ho; Lee, Bongju; Yoo, Suk Jae; Kwon, Myeon

    2007-01-01

    A Multi-Purpose Plasma (MP 2 ) facility has been renovated from Hanbit mirror device [Kwon et al., Nucl. Fusion 43, 686 (2003)] by adopting the same philosophy of diversified plasma simulator (DiPS) [Chung et al., Contrib. Plasma Phys. 46, 354 (2006)] by installing two plasma sources: LaB 6 (dc) and helicon (rf) plasma sources; and making three distinct simulators: divertor plasma simulator, space propulsion simulator, and astrophysics simulator. During the first renovation stage, a honeycomblike large area LaB 6 (HLA-LaB 6 ) cathode was developed for the divertor plasma simulator to improve the resistance against the thermal shock fragility for large and high density plasma generation. A HLA-LaB 6 cathode is composed of the one inner cathode with 4 in. diameter and the six outer cathodes with 2 in. diameter along with separate graphite heaters. The first plasma is generated with Ar gas and its properties are measured by the electric probes with various discharge currents and magnetic field configurations. Plasma density at the middle of central cell reaches up to 2.6x10 12 cm -3 , while the electron temperature remains around 3-3.5 eV at the low discharge current of less than 45 A, and the magnetic field intensity of 870 G. Unique features of electric property of heaters, plasma density profiles, is explained comparing with those of single LaB 6 cathode with 4 in. diameter in DiPS

  4. Method and apparatus for generating and utilizing a compound plasma configuration

    International Nuclear Information System (INIS)

    Koloc, P.M.

    1977-01-01

    A method and apparatus for generating and utilizing a compound plasma configuration is disclosed. The plasma configuration includes a central toroidal plasma with electrical currents surrounded by a generally ellipsoidal mantle of ionized particles or electrically conducting matter. The preferred methods of forming this compound plasma configuration include the steps of forming a helical ionized path in a gaseous medium and simultaneously discharging a high potential through the ionized path to produce a helical or heliform current which collapses on itself to produce a toroidal current, or generating a toroidal plasmoid, supplying magnetic energy to the plasmoid, and applying fluid pressure external to the plasmoid. The apparatus of the present invention includes a pressure chamber wherein the compound plasma configuration can be isolated or compressed by fluid or other forms of mechanical or magnetic pressure. 47 claims, 10 figures

  5. Ball lightning as a spherical plasma configuration of relevance to industrial plasma engineering

    International Nuclear Information System (INIS)

    Roth, J.R.

    1992-01-01

    One of the most interesting spherical plasma configurations found in nature is ball lightning, which has been extensively observed in atmospheric air, usually in association with thunderstorms. If the physical processes responsible for ball lightning were understood, this knowledge would have very interesting implications not only for fusion research, but also for industrial plasma engineering. The ability to create a steady-state atmospheric glow discharge would allow many surface modification and other plasma processing applications to be carried out under atmospheric conditions, rather than in expensive vacuum systems which enforce batch processing operations. The existence of ball lightning offers encouragement for the belief that a steady-state atmospheric glow discharge may be possible. Much progress has been made in theoretical attempts to understand ball lightning, perhaps the most comprehensive of which is the Koloc model. This and related models have not satisfactorily dealt with the long plasma lifetimes in the face of electron scattering at atmospheric density. This leads to an unsatisfactory aspect of the Koloc model, the requirement of a shell of relativistic electrons with very low Coulomb scattering cross sections. This last major conceptual roadblock in understanding ball lightning may have been removed by the recent suggestion of Witalis who pointed out that atmospheric gases, or their products, can exhibit the Ramsauer effect, extremely low electron scattering cross sections at low electron kinetic temperatures, on the order of one eV. This recent progress in ball lightning models has stimulated research aimed at producing a steady state glow discharge in air at atmospheric pressure. Such a glow discharge in argon with a few ppm of acetone has been reported by Kanda, et al. At the UTK Plasma Science Laboratory, the authors have generated at 2.8 liter plasma in a steady-state atmospheric pressure glow discharge in helium and other gases

  6. Plasma phenomenology in astrophysical systems: Radio-sources and jets

    International Nuclear Information System (INIS)

    Montani, Giovanni; Petitta, Jacopo

    2014-01-01

    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

  7. Molecular dynamics simulation of equilibrium configurations of plasmas containing multi-species dusts

    International Nuclear Information System (INIS)

    Liu, Yanhong; Chew, Lock Yue

    2007-01-01

    Equilibrium configurations of dusty plasmas with grains of different sizes, which interact through a screened Coulomb force field and confined by a two-dimensional quadratic potential, are studied using molecular dynamics simulation. The system configuration depends on the sizes, masses and charges of the grain species as well as the screening strength of the background plasma. The consideration of the grain size has established a different equilibrium configuration relative to that of point grains. In the new configurations, grains of different species separate into different shells, with the grains of larger mass and charge located away from the system center, forming a shell that surrounds the grains of smaller mass and charge at the system center. This configuration occurs beyond a critical grain radius, and its structure and size are determined by the competing effects between the inter-grain electrostatic repulsive force, the screening effect of the plasma and the mass-dependent confinement force of the quadratic potential

  8. RF Plasma modeling of the Linac4 H− ion source

    CERN Document Server

    Mattei, S; Hatayama, A; Lettry, J; Kawamura, Y; Yasumoto, M; Schmitzer, C

    2013-01-01

    This study focuses on the modelling of the ICP RF-plasma in the Linac4 H− ion source currently being constructed at CERN. A self-consistent model of the plasma dynamics with the RF electromagnetic field has been developed by a PIC-MCC method. In this paper, the model is applied to the analysis of a low density plasma discharge initiation, with particular interest on the effect of the external magnetic field on the plasma properties, such as wall loss, electron density and electron energy. The use of a multi-cusp magnetic field effectively limits the wall losses, particularly in the radial direction. Preliminary results however indicate that a reduced heating efficiency results in such a configuration. The effect is possibly due to trapping of electrons in the multi-cusp magnetic field, preventing their continuous acceleration in the azimuthal direction.

  9. Electrode configuration for extreme-UV electrical discharge source

    Science.gov (United States)

    Spence, Paul Andrew; Fornaciari, Neal Robert; Chang, Jim Jihchyun

    2002-01-01

    It has been demonstrated that debris generation within an electric capillary discharge source, for generating extreme ultraviolet and soft x-ray, is dependent on the magnitude and profile of the electric field that is established along the surfaces of the electrodes. An electrode shape that results in uniform electric field strength along its surface has been developed to minimize sputtering and debris generation. The electric discharge plasma source includes: (a) a body that defines a circular capillary bore that has a proximal end and a distal end; (b) a back electrode positioned around and adjacent to the distal end of the capillary bore wherein the back electrode has a channel that is in communication with the distal end and that is defined by a non-uniform inner surface which exhibits a first region which is convex, a second region which is concave, and a third region which is convex wherein the regions are viewed outwardly from the inner surface of the channel that is adjacent the distal end of the capillary bore so that the first region is closest to the distal end; (c) a front electrode positioned around and adjacent to the proximal end of the capillary bore wherein the front electrode has an opening that is communication with the proximal end and that is defined by a non-uniform inner surface which exhibits a first region which is convex, a second region which is substantially linear, and third region which is convex wherein the regions are viewed outwardly from the inner surface of the opening that is adjacent the proximal end of the capillary bore so that the first region is closest to the proximal end; and (d) a source of electric potential that is connected across the front and back electrodes.

  10. Simple microwave plasma source at atmospheric pressure

    International Nuclear Information System (INIS)

    Kim, Jeong H.; Hong, Yong C.; Kim, Hyoung S.; Uhm, Han S.

    2003-01-01

    We have developed a thermal plasma source operating without electrodes. One electrodeless torch is the microwave plasma-torch, which can produce plasmas in large quantities. We can generate plasma at an atmospheric pressure by marking use of the same magnetrons used as commercial microwave ovens. Most of the magnetrons are operated at the frequency of 2.45 GHz; the magnetron power microwave is about 1kW. Electromagnetic waves from the magnetrons propagate through a shorted waveguide. Plasma was generated under a resonant condition, by an auxiliary ignition system. The plasma is stabilized by vortex stabilization. Also, a high-power and high-efficiency microwave plasma-torch has been operated in air by combining two microwave plasma sources with 1kW, 2.45 GHz. They are arranged in series to generate a high-power plasma flame. The second torch adds all its power to the plasma flame of the first torch. Basically, electromagnetic waves in the waveguide were studied by a High Frequency Structure Simulator (HFSS) code and preliminary experiments were conducted

  11. Design of a novel high efficiency antenna for helicon plasma sources

    Science.gov (United States)

    Fazelpour, S.; Chakhmachi, A.; Iraji, D.

    2018-06-01

    A new configuration for an antenna, which increases the absorption power and plasma density, is proposed for helicon plasma sources. The influence of the electromagnetic wave pattern symmetry on the plasma density and absorption power in a helicon plasma source with a common antenna (Nagoya) is analysed by using the standard COMSOL Multiphysics 5.3 software. In contrast to the theoretical model prediction, the electromagnetic wave does not represent a symmetric pattern for the common Nagoya antenna. In this work, a new configuration for an antenna is proposed which refines the asymmetries of the wave pattern in helicon plasma sources. The plasma parameters such as plasma density and absorption rate for a common Nagoya antenna and our proposed antenna under the same conditions are studied using simulations. In addition, the plasma density of seven operational helicon plasma source devices, having a common Nagoya antenna, is compared with the simulation results of our proposed antenna and the common Nagoya antenna. The simulation results show that the density of the plasma, which is produced by using our proposed antenna, is approximately twice in comparison to the plasma density produced by using the common Nagoya antenna. In fact, the simulation results indicate that the electric and magnetic fields symmetry of the helicon wave plays a vital role in increasing wave-particle coupling. As a result, wave-particle energy exchange and the plasma density of helicon plasma sources will be increased.

  12. Bifurcation of plasma balls and black holes to Lobed configurations

    International Nuclear Information System (INIS)

    Cardoso, Vitor; Dias, Oscar J.C.

    2009-01-01

    At high energy densities any quantum field theory is expected to have an effective hydrodynamic description. When combined with the gravity/gauge duality an unified picture emerges, where gravity itself can have a formal holographic hydrodynamic description. This provides a powerful tool to study black holes in a hydrodynamic setup. We study the stability of plasma balls, holographic duals of Scherck-Schwarz (SS) AdS black holes. We find that rotating plasma balls are unstable against m-lobed perturbations for rotation rates higher than a critical value. This unstable mode signals a bifurcation to a new branch of non-axisymmetric stationary solutions which resemble a 'peanut-like' rotating plasma. The gravitational dual of the rotating plasma ball must then be unstable and possibly decay to a non-axisymmetric long-lived SS AdS black hole. This instability provides therefore a mechanism that bounds the rotation of SS black holes. Our results are strictly valid for the SS AdS gravity theory dual to a SS gauge theory. The latter is particularly important because it shares common features with QCD, namely it is non-conformal, non-supersymmetric and has a confinement/deconfinement phase transition. We focus our analysis in 3-dimensional plasmas dual to SS AdS 5 black holes, but many of our results should extend to higher dimensions and to other gauge theory/gravity dualities with confined/deconfined phases and admitting a fluid description.

  13. Detection of electric field around field-reversed configuration plasma

    International Nuclear Information System (INIS)

    Ikeyama, Taeko; Hiroi, Masanori; Nogi, Yasuyuki; Ohkuma, Yasunori

    2010-01-01

    Electric-field probes consisting of copper plates are developed to measure electric fields in a vacuum region around a plasma. The probes detect oscillating electric fields with a maximum strength of approximately 100 V/m through a discharge. Reproducible signals from the probes are obtained with an unstable phase dominated by a rotational instability. It is found that the azimuthal structure of the electric field can be explained by the sum of an n=2 mode charge distribution and a convex-surface electron distribution on the deformed separatrix at the unstable phase. The former distribution agrees with that anticipated from the diamagnetic drift motions of plasma when the rotational instability occurs. The latter distribution suggests that an electron-rich plasma covers the separatrix.

  14. Plasma x-ray radiation source.

    Science.gov (United States)

    Popkov, N F; Kargin, V I; Ryaslov, E A; Pikar', A S

    1995-01-01

    This paper gives the results of studies on a plasma x-ray source, which enables one to obtain a 2.5-krad radiation dose per pulse over an area of 100 cm2 in the quantum energy range from 20 to 500 keV. Pulse duration is 100 ns. Spectral radiation distributions from a diode under various operation conditions of a plasma are obtained. A Marx generator served as an initial energy source of 120 kJ with a discharge time of T/4 = 10-6 s. A short electromagnetic pulse (10-7 s) was shaped using plasma erosion opening switches.

  15. Experimental investigation of plasma sheaths in magnetic mirror and cusp configurations

    Science.gov (United States)

    Jiang, Zhengqi; Wei, Zi-an; Ma, J. X.

    2017-11-01

    Sheath structures near a metal plate in a magnetized plasma were experimentally investigated in magnetic mirror and cusp configurations. Plasma parameters and the sheath potential distributions were probed by a planar and an emissive probe, respectively. The measured sheath profiles in the mirror configuration show that the sheath thickness first decreases and then increases when the magnetic strength is raised. A magnetic flux-tube model was used to explain this result. In the cusp configuration, the measured sheath thickness decreases with the increase of the coil current creating the magnetic cusp. However, when normalized by the electron Debye length, the dependence of the sheath thickness on the coil current is reversed.

  16. Plasma and Ion Sources in Large Area Coatings: A Review

    Energy Technology Data Exchange (ETDEWEB)

    Anders, Andre

    2005-02-28

    Efficient deposition of high-quality coatings often requires controlled application of excited or ionized particles. These particles are either condensing (film-forming) or assisting by providing energy and momentum to the film growth process, resulting in densification, sputtering/etching, modification of stress, roughness, texture, etc. In this review, the technical means are surveyed enabling large area application of ions and plasmas, with ion energies ranging from a few eV to a few keV. Both semiconductortype large area (single wafer or batch processing with {approx} 1000 cm{sup 2}) and in-line web and glass-coating-type large area (> 10{sup 7} m{sup 2} annually) are considered. Characteristics and differences between plasma and ion sources are explained. The latter include gridded and gridless sources. Many examples are given, including sources based on DC, RF, and microwave discharges, some with special geometries like hollow cathodes and E x B configurations.

  17. Open-Circuit End Effect of Microstrip Line Configuration in Plasma Medium

    Directory of Open Access Journals (Sweden)

    Prem Bhushan Mital

    1996-01-01

    Full Text Available The extension in length for open microstrip configuration in plasma media is determined using spectral domain technique under quasi static approach [1, 2]. The results were verified by modifying Hammerstad equation for plasma media. Good agreement is found between the two results.

  18. Effects of magnetic configuration on hot electrons in highly charged ECR plasma

    International Nuclear Information System (INIS)

    Zhao, H Y; Zhao, H W; Sun, L T; Wang, H; Ma, B H; Zhang, X Zh; Li, X X; Ma, X W; Zhu, Y H; Lu, W; Shang, Y; Xie, D Z

    2009-01-01

    To investigate the hot electrons in highly charged electron cyclotron resonance (ECR) plasma, Bremsstrahlung radiations were measured on two ECR ion sources at the Institute of Modern Physics. Used as a comparative index of the mean energy of the hot electrons, a spectral temperature, T spe , is derived through a linear fitting of the spectra in a semi-logarithmic representation. The influences of the external source parameters, especially the magnetic configuration, on the hot electrons are studied systematically. This study has experimentally demonstrated the importance of high microwave frequency and high magnetic field in the electron resonance heating to produce a high density of hot electrons, which is consistent with the empirical ECR scaling laws. The experimental results have again shown that a good compromise is needed between the ion extraction and the plasma confinement for an efficient production of highly charged ion beams. In addition, this investigation has shown that the correlation between the mean energy of the hot electrons and the magnetic field gradient at the ECR is well in agreement with the theoretical models.

  19. On plasma ion beam formation in the Advanced Plasma Source

    International Nuclear Information System (INIS)

    Harhausen, J; Foest, R; Hannemann, M; Ohl, A; Brinkmann, R P; Schröder, B

    2012-01-01

    The Advanced Plasma Source (APS) is employed for plasma ion-assisted deposition (PIAD) of optical coatings. The APS is a hot cathode dc glow discharge which emits a plasma ion beam to the deposition chamber at high vacuum (p ≲ 2 × 10 −4 mbar). It is established as an industrial tool but to date no detailed information is available on plasma parameters in the process chamber. As a consequence, the details of the generation of the plasma ion beam and the reasons for variations of the properties of the deposited films are barely understood. In this paper the results obtained from Langmuir probe and retarding field energy analyzer diagnostics operated in the plasma plume of the APS are presented, where the source was operated with argon. With increasing distance to the source exit the electron density (n e ) is found to drop by two orders of magnitude and the effective electron temperature (T e,eff ) drops by a factor of five. The parameters close to the source region read n e ≳ 10 11 cm −3 and T e,eff ≳ 10 eV. The electron distribution function exhibits a concave shape and can be described in the framework of the non-local approximation. It is revealed that an energetic ion population leaves the source region and a cold ion population in the plume is build up by charge exchange collisions with the background neutral gas. Based on the experimental data a scaling law for ion beam power is deduced, which links the control parameters of the source to the plasma parameters in the process chamber. (paper)

  20. Suppression of plasma turbulence during optimised shear configurations in JET

    International Nuclear Information System (INIS)

    Conway, G.D.; Borba, D.N.; Alper, B.

    1999-08-01

    Density turbulence suppression is observed in the internal transport barrier (ITB) region of JET discharges with optimised magnetic shear. The suppression occurs in two stages. First, low frequency turbulence is reduced across the plasma core by a toroidal velocity shear generated by intense auxiliary heating. Then when the ITB forms, high frequency turbulence is reduced locally within the steep pressure gradient region of the ITB, consistent with the effects of enhanced E x B poloidal shear. The turbulence suppression is correlated with reduced plasma transport and improved fusion performance. Much effort has been spent in recent years in developing alternative scenarios for operating tokamak fusion reactors. One particular scenario involves reversing or reducing the central magnetic shear to form an internal transport barrier (ITB). The result is reduced plasma core energy transport and enhanced fusion performance. It is believed that ITBs may be formed through a combination of E x B velocity shear and magnetic shear stabilisation of plasma turbulence and instabilities. In this Letter we present results from JET optimised shear discharges showing that turbulence suppression during ITB formation occurs in two stages. First low frequency turbulence is reduced across the plasma core, coinciding with a region of strong toroidal velocity shear; then high frequency turbulence is locally suppressed around the ITB region, consistent with enhanced pressure gradient driven E x B poloidal shear. The measurements were made using a system of X-mode reflectometers consisting of two, dual-channel toroidal correlation reflectometers at 75 GHz (covering plasma outboard edge) and 105 GHz (core and inboard edge), and a 92-96 GHz swept frequency radial correlation reflectometer (plasma core). Reflectometry is a powerful tool for measuring density fluctuations. The highly localised reflection of the microwave beam gives excellent spatial localisation. Measurements can be made

  1. Formation of Field-reversed-Configuration Plasma with Punctuated-betatron-orbit Electrons

    International Nuclear Information System (INIS)

    Welch, D.R.; Cohen, S.A.; Genoni, T.C.; Glasser, A.H.

    2010-01-01

    We describe ab initio, self-consistent, 3D, fully electromagnetic numerical simulations of current drive and field-reversed-configuration plasma formation by odd-parity rotating magnetic fields (RMFo). Magnetic-separatrix formation and field reversal are attained from an initial mirror configuration. A population of punctuated-betatron-orbit electrons, generated by the RMFo, carries the majority of the field-normal azimuthal electrical current responsible for field reversal. Appreciable current and plasma pressure exist outside the magnetic separatrix whose shape is modulated by the RMFo phase. The predicted plasma density and electron energy distribution compare favorably with RMFo experiments.

  2. Measuring the Plasma Density of a Ferroelectric Plasma Source in an Expanding Plasma

    International Nuclear Information System (INIS)

    Dunaevsky, A.; Fisch, N.J.

    2003-01-01

    The initial density and electron temperature at the surface of a ferroelectric plasma source were deduced from floating probe measurements in an expanding plasma. The method exploits negative charging of the floating probe capacitance by fast flows before the expanding plasma reaches the probe. The temporal profiles of the plasma density can be obtained from the voltage traces of the discharge of the charged probe capacitance by the ion current from the expanding plasma. The temporal profiles of the plasma density, at two different distances from the surface of the ferroelectric plasma source, could be further fitted by using the density profiles for the expanding plasma. This gives the initial values of the plasma density and electron temperature at the surface. The method could be useful for any pulsed discharge, which is accompanied by considerable electromagnetic noise, if the initial plasma parameters might be deduced from measurements in expanding plasma

  3. Construction of a high beta plasma source

    International Nuclear Information System (INIS)

    Naraghi, M.; Torabi-Fard, A.

    1976-02-01

    A high beta plasma source has been designed and constructed. This source will serve as a means of developing and exercising different diagnostic techniques as required for ALVAND I, linear theta pinch experiment. Also, it will serve to acquaint the technicians with some of the techniques and safety rules of high voltage and capacitor discharge experiments. The operating parameters of the theta pinch and Z-pinch preionization is presented and the program of diagnostic measurements on the high beta plasma source is discussed

  4. Consideration of beam plasma ion-source

    International Nuclear Information System (INIS)

    Sano, Fumimichi; Kusano, Norimasa; Ishida, Yoshihiro; Ishikawa, Junzo; Takagi, Toshinori

    1976-01-01

    Theoretical and experimental analyses and their comparison were made on the plasma generation and on the beam extraction for the beam plasma ion-source. The operational principle and the structure of the ion-source are explained in the first part. Considerations are given on the electron beam-plasma interaction and the resulting generation of high frequency or microwaves which in turn increases the plasma density. The flow of energy in this system is also explained in the second part. The relation between plasma density and the imaginary part of frequency is given by taking the magnetic flux density, the electron beam energy, and the electron beam current as parameters. The relations between the potential difference between collector and drift tube and the plasma density or the ion-current are also given. Considerations are also given to the change of the plasma density due to the change of the magnetic flux density at drift tube, the change of the electron beam energy, and the change of the electron beam current. The third part deals with the extraction characteristics of the ion beam. The structure of the multiple-aperture electrode and the relation between plasma density and the extracted ion current are explained. (Aoki, K.)

  5. Moderate pressure plasma source of nonthermal electrons

    Science.gov (United States)

    Gershman, S.; Raitses, Y.

    2018-06-01

    Plasma sources of electrons offer control of gas and surface chemistry without the need for complex vacuum systems. The plasma electron source presented here is based on a cold cathode glow discharge (GD) operating in a dc steady state mode in a moderate pressure range of 2–10 torr. Ion-induced secondary electron emission is the source of electrons accelerated to high energies in the cathode sheath potential. The source geometry is a key to the availability and the extraction of the nonthermal portion of the electron population. The source consists of a flat and a cylindrical electrode, 1 mm apart. Our estimates show that the length of the cathode sheath in the plasma source is commensurate (~0.5–1 mm) with the inter-electrode distance so the GD operates in an obstructed regime without a positive column. Estimations of the electron energy relaxation confirm the non-local nature of this GD, hence the nonthermal portion of the electron population is available for extraction outside of the source. The use of a cylindrical anode presents a simple and promising method of extracting the high energy portion of the electron population. Langmuir probe measurements and optical emission spectroscopy confirm the presence of electrons with energies ~15 eV outside of the source. These electrons become available for surface modification and radical production outside of the source. The extraction of the electrons of specific energies by varying the anode geometry opens exciting opportunities for future exploration.

  6. Resonant power absorption in helicon plasma sources

    International Nuclear Information System (INIS)

    Chen Guangye; Arefiev, Alexey V.; Bengtson, Roger D.; Breizman, Boris N.; Lee, Charles A.; Raja, Laxminarayan L.

    2006-01-01

    Helicon discharges produce plasmas with a density gradient across the confining magnetic field. Such plasmas can create a radial potential well for nonaxisymmetric whistlers, allowing radially localized helicon (RLH) waves. This work presents new evidence that RLH waves play a significant role in helicon plasma sources. An experimentally measured plasma density profile in an argon helicon discharge is used to calculate the rf field structure. The calculations are performed using a two-dimensional field solver under the assumption that the density profile is axisymmetric. It is found that RLH waves with an azimuthal wave number m=1 form a standing wave structure in the axial direction and that the frequency of the RLH eigenmode is close to the driving frequency of the rf antenna. The calculated resonant power absorption, associated with the RLH eigenmode, accounts for most of the rf power deposited into the plasma in the experiment

  7. Plasma-based EUV light source

    Science.gov (United States)

    Shumlak, Uri; Golingo, Raymond; Nelson, Brian A.

    2010-11-02

    Various mechanisms are provided relating to plasma-based light source that may be used for lithography as well as other applications. For example, a device is disclosed for producing extreme ultraviolet (EUV) light based on a sheared plasma flow. The device can produce a plasma pinch that can last several orders of magnitude longer than what is typically sustained in a Z-pinch, thus enabling the device to provide more power output than what has been hitherto predicted in theory or attained in practice. Such power output may be used in a lithography system for manufacturing integrated circuits, enabling the use of EUV wavelengths on the order of about 13.5 nm. Lastly, the process of manufacturing such a plasma pinch is discussed, where the process includes providing a sheared flow of plasma in order to stabilize it for long periods of time.

  8. A novel plasma source for sterilization of living tissues

    International Nuclear Information System (INIS)

    Martines, E; Zuin, M; Cavazzana, R; Gazza, E; Serianni, G; Spagnolo, S; Spolaore, M; Leonardi, A; Deligianni, V; Brun, P; Aragona, M; Castagliuolo, I; Brun, P

    2009-01-01

    A source for the production of low-power plasmas at atmospheric pressure, to be used for the nondamaging sterilization of living tissues, is presented. The source, powered by radiofrequency and working with a helium flow, has a specific configuration, studied to prevent the formation of electric arcs dangerous to living matter. It is capable of killing different types of bacteria with a decimal reduction time of 1-2 min; on the contrary, human cells such as conjunctival fibroblasts were found to be almost unharmed by the plasma. A high concentration of OH radicals, likely to be the origin of the sterilizing effect, is detected through their UV emission lines. The effect of the UV and the OH radicals on the fibroblasts was analysed and no significant effects were detected.

  9. Design and field configuration for a 14.4 GHz ECR ion source in Kolkata

    International Nuclear Information System (INIS)

    Rashid, M.H.; Bose, D.K.; Mallik, C.; Bhandari, R.K.

    2001-01-01

    The K500 cyclotron under construction will be capable of accelerating ions like O 6+ , Ne 4+ , Ar 16+ , Kr 27+ etc. We aim to get ∼200 euA maximum intensity of the extracted beam of O 6+ from the ion source and decided to have >2B ECR magnetic field on the cylindrical surface and the injection ends of the plasma chamber (P Ch) and slightly less than this at the extraction end. The success of the high field operation of ECRs at other places (U-AECR at LBL) suggests generation of proper magnetic field configuration for the 14.4 GHz microwave heating. The absolute composite magnetic field have been evaluated due to the coils (C1,C2) at the two ends and a -ve coil (NC) at the mid-length and a Halbach type sextupole (PM-Hex)

  10. Characterization of the equilibrium configuration for modulated beams in a plasma wakefield accelerator

    CERN Document Server

    Martorelli, Roberto

    2016-01-01

    We analyze the equilibrium configuration for a modulated beam with sharp boundaries exposed to the fields self-generated by the interaction with a plasma. Through a semi-analytical approach we show the presence of multiple equilibrium configurations and we determine the one more suitable for wakefield excitation. Once pointed out the absence of confinement for the front of the beam and the consequently divergence driven by the emittance, we study the evolution of the equilibrium configuration while propagating in the plasma, discarding all the others time-dependencies. We show the onset of a rigid backward drift of the equilibrium configuration and we provide an explanation in the increasing length of the first bunch.

  11. Volumetric plasma source development and characterization

    International Nuclear Information System (INIS)

    Crain, Marlon D.; Maron, Yitzhak; Oliver, Bryan Velten; Starbird, Robert L.; Johnston, Mark D.; Hahn, Kelly Denise; Mehlhorn, Thomas Alan; Droemer, Darryl W.

    2008-01-01

    The development of plasma sources with densities and temperatures in the 10 15 -10 17 cm -3 and 1-10eV ranges which are slowly varying over several hundreds of nanoseconds within several cubic centimeter volumes is of interest for applications such as intense electron beam focusing as part of the x-ray radiography program. In particular, theoretical work (1,2) suggests that replacing neutral gas in electron beam focusing cells with highly conductive, pre-ionized plasma increases the time-averaged e-beam intensity on target, resulting in brighter x-ray sources. This LDRD project was an attempt to generate such a plasma source from fine metal wires. A high voltage (20-60kV), high current (12-45kA) capacitive discharge was sent through a 100 (micro)m diameter aluminum wire forming a plasma. The plasma's expansion was measured in time and space using spectroscopic techniques. Lineshapes and intensities from various plasma species were used to determine electron and ion densities and temperatures. Electron densities from the mid-10 15 to mid-10 16 cm -3 were generated with corresponding electron temperatures of between 1 and 10eV. These parameters were measured at distances of up to 1.85 cm from the wire surface at times in excess of 1 (micro)s from the initial wire breakdown event. In addition, a hydrocarbon plasma from surface contaminants on the wire was also measured. Control of these contaminants by judicious choice of wire material, size, and/or surface coating allows for the ability to generate plasmas with similar density and temperature to those given above, but with lower atomic masses

  12. Plasma current sustained by fusion charged particles in a field reversed configuration

    International Nuclear Information System (INIS)

    Berk, H.L.; Momota, H.; Tajima, T.

    1987-04-01

    The distribution of energetic charged particles generated by thermonuclear fusion reactions in a field reversed configuration (FRC) are studied analytically and numerically. A fraction of the charged fusion products escapes directly while the others are trapped to form a directed particle flow parallel to the plasma current. It is shown that the resultant current density produced by these fusion charged particles can be comparable to background plasma current density that produces the original field reversed configuration in a D- 3 He reactor. Self-consistent equilibria arising from the currents of the background plasma and proton fusion products are constructed where the Larmor radius of the fusion product is of arbitrary size. Reactor relevant parameters are examined, such as how the fusion reactivity rate varies as a result of supporting the pressure associated with the fusion products. We also model the synchrotron emission from various pressure profiles and quantitatively show how synchrotron losses vary with different pressure profiles in an FRC configuration

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

    International Nuclear Information System (INIS)

    Singh, M. J.; Bandyopadhyay, M.; Yadava, Ratnakar; Chakraborty, A. K.; Bansal, G.; Gahlaut, A.; Soni, J.; Kumar, Sunil; Pandya, K.; Parmar, K. G.; Sonara, J.; Kraus, W.; Heinemann, B.; Riedl, R.; Obermayer, S.; Martens, C.; Franzen, P.; Fantz, U.

    2011-01-01

    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 18 /m 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.

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

    Science.gov (United States)

    Singh, M. J.; Bandyopadhyay, M.; Bansal, G.; Gahlaut, A.; Soni, J.; Kumar, Sunil; Pandya, K.; Parmar, K. G.; Sonara, J.; Yadava, Ratnakar; Chakraborty, A. K.; Kraus, W.; Heinemann, B.; Riedl, R.; Obermayer, S.; Martens, C.; Franzen, P.; Fantz, U.

    2011-09-01

    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 0.5-1×1018/m3, 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.

  15. Effect of configuration widths on the spectra of local thermodynamic equilibrium plasmas

    International Nuclear Information System (INIS)

    Bar-Shalom, A.; Oreg, J.; Goldstein, W.H.

    1995-01-01

    We present the extension of the supertransition-array (STA) theory to include configuration widths in the spectra of local thermodynamic equilibrium (LTE) plasmas. Exact analytic expressions for the moments of a STA are given, accounting for the detailed contributions of individual levels within the configurations that belong to a STA. The STA average energy is shifted and an additional term appears in its variance. Various cases are presented, demonstrating the effect of these corrections on the LTE spectrum

  16. Adaptation of metal arc plasma source to plasma source ion implantation

    International Nuclear Information System (INIS)

    Shamim, M.M.; Fetherston, R.P.; Conrad, J.R.

    1995-01-01

    In Plasma Source Ion Implantation (PSII) a target is immersed in a plasma and a train of high negative voltage pulses is applied to accelerate ions into the target and to modify the properties in the near surface region. In PSII, until now the authors have been using gaseous species to generate plasmas. However metal ion plasma may be used to modify the surface properties of material for industrial applications. Conventionally the ion implantation of metal ions is performed using beam line accelerators which have complex engineering and high cost. The employment of a metal arc source to PSII has tremendous potential due to its ability to process the conformal surfaces, simple engineering and cost effectiveness. They have installed metal arc source for generation of titanium plasma. Currently, they are investigating the properties of titanium plasma and material behavior of titanium implanted aluminum and 52100 steel. The recent results of this investigation are presented

  17. High-Current Plasma Electron Sources

    International Nuclear Information System (INIS)

    Gushenets, J.Z.; Krokhmal, V.A.; Krasik, Ya. E.; Felsteiner, J.; Gushenets, V.

    2002-01-01

    In this report we present the design, electrical schemes and preliminary results of a test of 4 different electron plasma cathodes operating under Kg h-voltage pulses in a vacuum diode. The first plasma cathode consists of 6 azimuthally symmetrically distributed arc guns and a hollow anode having an output window covered by a metal grid. Plasma formation is initiated by a surface discharge over a ceramic washer placed between a W-made cathode and an intermediate electrode. Further plasma expansion leads to a redistribution of the discharge between the W-cathode and the hollow anode. An accelerating pulse applied between the output anode grid and the collector extracts electrons from this plasma. The operation of another plasma cathode design is based on Penning discharge for preliminary plasma formation. The main glow discharge occurs between an intermediate electrode of the Penning gun and the hollow anode. To keep the background pressure in the accelerating gap at P S 2.5x10 4 Torr either differential pumping or a pulsed gas puff valve were used. The operation of the latter electron plasma source is based on a hollow cathode discharge. To achieve a sharp pressure gradient between the cathode cavity and the accelerating gap a pulsed gas puff valve was used. A specially designed ferroelectric plasma cathode initiated plasma formation inside the hollow cathode. This type of the hollow cathode discharge ignition allowed to achieve a discharge current of 1.2 kA at a background pressure of 2x10 4 Torr. All these cathodes were developed and initially tested inside a planar diode with a background pressure S 2x10 4 Torr under the same conditions: accelerating voltage 180 - 300 kV, pulse duration 200 - 400 ns, electron beam current - 1 - 1.5 kA, and cross-sectional area of the extracted electron beam 113 cm 2

  18. Characterization of the pulse plasma source

    International Nuclear Information System (INIS)

    Milosavljevic, V; Karkari, S K; Ellingboe, A R

    2007-01-01

    Characterization of the pulse plasma source through the determination of the local thermodynamic equilibrium (LTE) threshold is described. The maximum electron density measured at the peak in discharge current is determined by the width of the He II Paschen alpha spectral line, and the electron temperature is determined from the ratios of the relative intensities of spectral lines emitted from successive ionized stages of atoms. The electron density and temperature maximum values are measured to be 1.3 x 10 17 cm -3 and 19 000 K, respectively. These are typical characteristics for low-pressure, pulsed plasma sources for input energy of 15.8 J at 130 Pa pressure in helium-argon mixture. The use of LTE-based analysis of the emission spectra is justified by measurement of the local plasma electron density at four positions in the discharge tube using a floating hairpin resonance probe. The hairpin resonance probe data are collected during the creation and decay phases of the pulse. From the spatio-temporal profile of the plasma density a 60 μs time-window during which LTE exists throughout the entire plasma source is determined

  19. Plasma sources of solar system magnetospheres

    CERN Document Server

    Blanc, Michel; Chappell, Charles; Krupp, Norbert

    2016-01-01

    This volume reviews what we know of the corresponding plasma source for each intrinsically magnetized planet. Plasma sources fall essentially in three categories: the solar wind, the ionosphere (both prevalent on Earth), and the satellite-related sources. Throughout the text, the case of each planet is described, including the characteristics, chemical composition and intensity of each source. The authors also describe how the plasma generated at the source regions is transported to populate the magnetosphere, and how it is later lost. To summarize, the dominant sources are found to be the solar wind and sputtered surface ions at Mercury, the solar wind and ionosphere at Earth (the relative importance of the two being discussed in a specific introductory chapter), Io at Jupiter and – a big surprise of the Cassini findings – Enceladus at Saturn. The situation for Uranus and Neptune, which were investigated by only one fly-by each, is still open and requires further studies and exploration. In the final cha...

  20. Spatial configuration of a plasma bunch formed under gyromagnetic resonance in a magnetic mirror trap

    Energy Technology Data Exchange (ETDEWEB)

    Andreev, V. V.; Novitskii, A. A.; Umnov, A. M.; Chuprov, D. V., E-mail: chu-d@mail.ru [Peoples’ Friendship University of Russia (Russian Federation)

    2016-06-15

    The spatial configuration of a relativistic plasma bunch generated under the gyromagnetic autoresonance and confined in a magnetic mirror trap has been studied experimentally and numerically. The characteristics of bremsstrahlung generated by the plasma bunch from the gas and chamber walls were investigated using X-ray spectroscopy and radiometry, which made it possible to determine the localization of the bunch and analyze the dynamics of its confinement.

  1. Electron density and temperature profile diagnostics for C-2 field reversed configuration plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Deng, B. H.; Kinley, J. S.; Schroeder, J. [Tri Alpha Energy, Inc., Rancho Santa Margarita, California 92688 (United States)

    2012-10-15

    The 9-point Thomson scattering diagnostic system for the C-2 field reversed configuration plasmas is improved and the measured electron temperature profiles are consistent with theoretical expectations. Rayleigh scattering revealed a finite line width of the ruby laser emission, which complicates density calibration. Taking advantage of the plasma wobble motion, density profile reconstruction accuracy from the 6-chord two-color CO{sub 2}/HeNe interferometer data is improved.

  2. Performance of a plasma opening switch in positive polarity on Gamble I using flashboard plasma sources

    International Nuclear Information System (INIS)

    Renk, T.J.

    1995-01-01

    The successful development of the Plasma Opening Switch (POS) for inductive storage applications has been largely confined to negative polarity operation. Some models of POS behavior suggest that this is because in a positive polarity coaxial configuration, the weaker magnetic field at the cathode position retards the switch opening process. This article describes experiments in which both conductor radii in the POS region were significantly reduced. Anode- and cathode-side current monitors indicate that voltages greater than open-circuit are generated at the POS position, but there is a significant amount of electron flow out of the POS, depending upon load impedance. Flow impedance analysis indicates that a relatively small gap appears in the POS plasma after switch opening. Switch performance is also compared between flashboard and carbon gun plasma sources, with the latter operated both in positive and negative polarity

  3. Interaction of Fast Ions with Global Plasma Modes in the C-2 Field Reversed Configuration Experiment

    Science.gov (United States)

    Smirnov, Artem; Dettrick, Sean; Clary, Ryan; Korepanov, Sergey; Thompson, Matthew; Trask, Erik; Tuszewski, Michel

    2012-10-01

    A high-confinement operating regime [1] with plasma lifetimes significantly exceeding past empirical scaling laws was recently obtained by combining plasma gun edge biasing and tangential Neutral Beam Injection (NBI) in the C-2 field-reversed configuration (FRC) experiment [2, 3]. We present experimental and computational results on the interaction of fast ions with the n=2 rotational and n=1 wobble modes in the C-2 FRC. It is found that the n=2 mode is similar to quadrupole magnetic fields in its detrimental effect on the fast ion transport due to symmetry breaking. The plasma gun generates an inward radial electric field, thus stabilizing the n=2 rotational instability without applying the quadrupole magnetic fields. The resultant FRCs are nearly axisymmetric, which enables fast ion confinement. The NBI further suppresses the n=2 mode, improves the plasma confinement characteristics, and increases the plasma configuration lifetime [4]. The n=1 wobble mode has relatively little effect on the fast ion transport, likely due to the approximate axisymmetry about the displaced plasma column. [4pt] [1] M. Tuszewski et al., Phys. Rev. Lett. 108, 255008 (2012).[0pt] [2] M. Binderbauer et al., Phys. Rev. Lett. 105, 045003 (2010).[0pt] [3] H.Y. Guo et al., Phys. Plasmas 18, 056110 (2011).[0pt] [4] M. Tuszewski et al., Phys. Plasmas 19, 056108 (2012)

  4. Formation of compact toroidal configurations for magnetic confinement of high temperature plasmas

    International Nuclear Information System (INIS)

    Fuentes, N.O.; Rodrigo, A.B.

    1986-01-01

    The formation stage of inverted magnetic field toroidal configurations (FRC) for hot plasmas confinement using a low energy linear theta pinch is studied. The diagnostic techniques used are based on optical spectroscopy, ultrarapid photography, magnetic probes and excluded flux compensated bonds. The generalities of the present research program, the used diagnostic techniques and the results obtained are discussed. (Author)

  5. Superposed epoch analysis of pressure and magnetic field configuration changes in the plasma sheet

    International Nuclear Information System (INIS)

    Kistler, L.M.; Moebius, E.; Baumjohann, W.; Nagai, T.

    1993-01-01

    The authors report on an analysis of pressure and magnetic configuration within the plasma sheet following the initiation of substorm events. They have constructed this time dependent picture by using an epoch analysis of data from the AMPTE/IRM spacecraft. This analysis procedure can be used to construct a unified picture of events, provided they are reproducible, from a statistical analysis of a series of point measurements. The authors first determine the time dependent pressure changes in the plasma sheet. With some simplifying assumptions they then determine the z dependence of the pressure profiles, and from this distribution determine how field lines in the plasma sheet map to the neutral sheet

  6. Effects of background neutral particles on a field-reversed configuration plasma in the translation process

    International Nuclear Information System (INIS)

    Matsuzawa, Yoshiki; Asai, Tomohiko; Takahashi, Tsutomu; Takahashi, Toshiki

    2008-01-01

    A field-reversed configuration (FRC) plasma was translated into a weakly ionized plasma and the effects of heating and particle buildup of the FRC plasma due to the background neutral particles and plasma injection in the translation process were investigated. Improvement of the particle and poloidal flux confinements and delay of onset of n=2 rotational instability were observed in the translation process. It was found that the internal structure of the plasma pressure (plasma temperature and density) at the separatrix and field null was deformed by the particle injection. FRC plasma translation through the background particles was equivalent to an end-on particle beam injection to the FRC plasma. Particles and energy were supplied during the translation. The results obtained for the phenomena of particle supply and plasma heating were also supported by the results of two-dimensional particle simulation. The effects of background particle injection appear to be a promising process for the regeneration of translation kinetic energy to plasma internal energy

  7. Configuration of electro-optic fire source detection system

    Science.gov (United States)

    Fabian, Ram Z.; Steiner, Zeev; Hofman, Nir

    2007-04-01

    The recent fighting activities in various parts of the world have highlighted the need for accurate fire source detection on one hand and fast "sensor to shooter cycle" capabilities on the other. Both needs can be met by the SPOTLITE system which dramatically enhances the capability to rapidly engage hostile fire source with a minimum of casualties to friendly force and to innocent bystanders. Modular system design enable to meet each customer specific requirements and enable excellent future growth and upgrade potential. The design and built of a fire source detection system is governed by sets of requirements issued by the operators. This can be translated into the following design criteria: I) Long range, fast and accurate fire source detection capability. II) Different threat detection and classification capability. III) Threat investigation capability. IV) Fire source data distribution capability (Location, direction, video image, voice). V) Men portability. ) In order to meet these design criteria, an optimized concept was presented and exercised for the SPOTLITE system. Three major modular components were defined: I) Electro Optical Unit -Including FLIR camera, CCD camera, Laser Range Finder and Marker II) Electronic Unit -including system computer and electronic. III) Controller Station Unit - Including the HMI of the system. This article discusses the system's components definition and optimization processes, and also show how SPOTLITE designers successfully managed to introduce excellent solutions for other system parameters.

  8. Interaction of ICRF power and edge plasma in Tore Supra ergodic divertor configuration

    International Nuclear Information System (INIS)

    Nguyen, F.; Grosman, A.; Basiuk, V.; Fraboulet, D.; Beaumont, B.; Becoulet, A.; Ghendrih, Ph.; Ladurelle, L.; Meslin, B.

    2000-01-01

    The coupling of ICRF power to plasma is a crucial problem in Tore Supra for high power and long pulse operations and depends greatly on the edge parameters, in particular on the edge density. Conversely, the behaviour of the bulk plasma is related to the edge conditions and the injection of RF power also induces major modifications on the edge plasma. Moreover, the Ergodic Divertor (ED) of Tore Supra imposes a complex configuration at the edge due to the presence of the magnetic perturbation. Several diagnostics are available to study the interaction of ICRF power with the edge plasma: Langmuir probes on the ED modules, infra red (IR) cameras, charge exchange neutral analysers. In minority heating scheme, the edge density is very sensitive to any perturbation in the high recycling regime which is always found in the ED configuration for relevant plasma parameters. Partially detached regimes, with or without inhomogeneities of density and temperature induced by the flux tubes of the laminar layer, are obtained for high resistance coupling values. The coupling is then not very robust and feedback control or antenna automatic matching techniques are developed. In fast wave electron heating scheme with ED, various fast wave absorption mechanisms (minority heating, Mode Conversion, Alfven resonance) are present at the plasma edge due to the large size of the plasma. The ICRF coupling is difficult due to the low fast wave direct electron damping, even with high hydrogen minority scheme. An increase of the injected ICRF power could improve this situation

  9. Impurity screening in high density plasmas in tokamaks with a limiter configuration

    International Nuclear Information System (INIS)

    Ferro, C.; Zanino, R.

    1992-01-01

    Impurity screening in high density plasmas in tokamaks with a limiter configuration is investigated by means of a simple semi-analytical model. An iterative scheme is devised, in order to determine self-consistently the values of scrape-off layer thickness, edge electron density and temperature, and main plasma contamination parameter Z eff , as a function of given average electron density and temperature in the main plasma and given input power. The model is applied to the poloidal limiter case of the Frascati Tokamak Upgrade, and results are compared with experimental data. A reasonable agreement between the trends is found, emphasizing the importance of a high edge plasma density for obtaining a clean main plasma in limiter tokamaks. (orig.)

  10. Burning plasmas in ITER for energy source

    International Nuclear Information System (INIS)

    Inoue, Nobuyuki

    2002-01-01

    Fusion research and development has two aspects. One is an academic research on science and technology, i.e., discovery and understanding of unexpected phenomena and, development of innovative technology, respectively. The other is energy source development to realize fusion as a viable energy future. Fusion research has been made remarkable progress in the past several decades, and ITER will soon realize burning plasma that is essential for both academic research and energy development. With ITER, scientific research on unknown phenomena such as self-organization of the plasma in burning state will become possible and it contributes to create a variety of academic outcome. Fusion researchers will have a responsibility to generate actual energy, and electricity generation immediately after the success of burning plasma control experiment in ITER is the next important step that has to be discussed seriously. (author)

  11. Burning plasmas in ITER for energy source

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, Nobuyuki [Atomic Energy Commission, Tokyo (Japan)

    2002-10-01

    Fusion research and development has two aspects. One is an academic research on science and technology, i.e., discovery and understanding of unexpected phenomena and, development of innovative technology, respectively. The other is energy source development to realize fusion as a viable energy future. Fusion research has been made remarkable progress in the past several decades, and ITER will soon realize burning plasma that is essential for both academic research and energy development. With ITER, scientific research on unknown phenomena such as self-organization of the plasma in burning state will become possible and it contributes to create a variety of academic outcome. Fusion researchers will have a responsibility to generate actual energy, and electricity generation immediately after the success of burning plasma control experiment in ITER is the next important step that has to be discussed seriously. (author)

  12. Formation of a field reversed configuration for magnetic and electrostatic confinement of plasma

    Science.gov (United States)

    Rostoker, Norman; Binderbauer, Michl

    2003-12-16

    A system and method for containing plasma and forming a Field Reversed Configuration (FRC) magnetic topology are described in which plasma ions are contained magnetically in stable, non-adiabatic orbits in the FRC. Further, the electrons are contained electrostatically in a deep energy well, created by tuning an externally applied magnetic field. The simultaneous electrostatic confinement of electrons and magnetic confinement of ions avoids anomalous transport and facilitates classical containment of both electrons and ions. In this configuration, ions and electrons may have adequate density and temperature so that upon collisions they are fused together by nuclear force, thus releasing fusion energy. Moreover, the fusion fuel plasmas that can be used with the present confinement system and method are not limited to neutronic fuels only, but also advantageously include advanced fuels.

  13. Plasma immersion ion implantation (and deposition) inside metallic tubes of different dimensions and configurations

    Science.gov (United States)

    Ueda, M.; Silva, C.; Santos, N. M.; Souza, G. B.

    2017-10-01

    There is a strong need for developing methods to coat or implant ions inside metallic tubes for many practical contemporary applications, both for industry and science. Therefore, stainless steel tubes with practical diameters of 4, 11 and 16 cm, but short lengths of 20 cm, were internally treated by nitrogen plasma immersion ion implantation (PIII). Different configurations as tube with lid in one of the ends or both sides open were tested for better PIII performance, in the case of smallest diameter tube. Among these PIII tests in tubes, using the 4 cm diameter one with a lid, it was possible to achieve tube temperatures of more than 700 °C in 15 min and maintain it during the whole treatment time (typically 2 h). Samples made of different materials were placed at the interior of the tube, as the monitors for posterior analysis, and the tube was solely pulsed by high voltage pulser producing high voltage glow discharge and hollow cathode discharge both driven by a moderate power source. In this experiment, samples of SS 304, pure Ti, Ti6Al4V and Si were used for the tests of the above methods. Results on the analysis of the surface of these nitrogen PIII treated materials, as well as on their processing methods, are presented and discussed in the paper.

  14. Microwave Plasma Sources for Gas Processing

    International Nuclear Information System (INIS)

    Mizeraczyk, J.; Jasinski, M.; Dors, M.; Zakrzewski, Z.

    2008-01-01

    In this paper atmospheric pressure microwave discharge methods and devices used for producing the non-thermal plasmas for processing of gases are presented. The main part of the paper concerns the microwave plasma sources (MPSs) for environmental protection applications. A few types of the MPSs, i.e. waveguide-based surface wave sustained MPS, coaxial-line-based and waveguide-based nozzle-type MPSs, waveguide-based nozzleless cylinder-type MPS and MPS for microdischarges are presented. Also, results of the laboratory experiments on the plasma processing of several highly-concentrated (up to several tens percent) volatile organic compounds (VOCs), including Freon-type refrigerants, in the moderate (200-400 W) waveguide-based nozzle-type MPS (2.45 GHz) are presented. The results showed that the microwave discharge plasma fully decomposed the VOCs at relatively low energy cost. The energy efficiency of VOCs decomposition reached 1000 g/kWh. This suggests that the microwave discharge plasma can be a useful tool for environmental protection applications. In this paper also results of the use of the waveguide-based nozzleless cylinder-type MPS to methane reforming into hydrogen are presented

  15. Alternative RF coupling configurations for H− ion sources

    International Nuclear Information System (INIS)

    Briefi, S.; Fantz, U.; Gutmann, P.

    2015-01-01

    RF heated sources for negative hydrogen ions both for fusion and accelerators require very high RF powers in order to achieve the required H − current what poses high demands on the RF generators and the RF circuit. Therefore it is highly desirable to improve the RF efficiency of the sources. This could be achieved by applying different RF coupling concepts than the currently used inductive coupling via a helical antenna, namely Helicon coupling or coupling via a planar ICP antenna enhanced with ferrites. In order to investigate the feasibility of these concepts, two small laboratory experiments have been set up. The PlanICE experiment, where the enhanced inductive coupling is going to be investigated, is currently under assembly. At the CHARLIE experiment systematic measurements concerning Helicon coupling in hydrogen and deuterium are carried out. The investigations show that a prominent feature of Helicon discharges occurs: the so-called low-field peak. This is a local improvement of the coupling efficiency at a magnetic field strength of a few mT which results in an increased electron density and dissociation degree. The full Helicon mode has not been achieved yet due to the limited available RF power and magnetic field strength but it might be sufficient for the application of the coupling concept to ion sources to operate the discharge in the low-field-peak region

  16. Simulation of a dense plasma focus x-ray source

    International Nuclear Information System (INIS)

    Stark, R.A.

    1994-01-01

    The authors are performing simulations of the magnetohydrodynamics of a Dense Plasma Focus (DPF) x-ray source located at Science Research Laboratory (SRL), Alameda, CA, in order to optimize its performance. The SRL DPF, which was developed as a compact source for x-ray lithography, operates at 20 Hz, giving x-ray power (9--14 Angstroms) of 500 W using neon gas. The simulations are performed with the two dimensional MHD code MACH2, developed by Mission Research Corporation, with a steady state corona model as the equation of state. The results of studies of the sensitivity of x-ray output to charging voltage and current, and to initial gas density will be presented. These studies should indicate ways to optimize x-ray production efficiency. Simulations of various inner electrode configurations will also be presented

  17. Material impacts and heat flux characterization of an electrothermal plasma source with an applied magnetic field

    Science.gov (United States)

    Gebhart, T. E.; Martinez-Rodriguez, R. A.; Baylor, L. R.; Rapp, J.; Winfrey, A. L.

    2017-08-01

    To produce a realistic tokamak-like plasma environment in linear plasma device, a transient source is needed to deliver heat and particle fluxes similar to those seen in an edge localized mode (ELM). ELMs in future large tokamaks will deliver heat fluxes of ˜1 GW/m2 to the divertor plasma facing components at a few Hz. An electrothermal plasma source can deliver heat fluxes of this magnitude. These sources operate in an ablative arc regime which is driven by a DC capacitive discharge. An electrothermal source was configured with two pulse lengths and tested under a solenoidal magnetic field to determine the resulting impact on liner ablation, plasma parameters, and delivered heat flux. The arc travels through and ablates a boron nitride liner and strikes a tungsten plate. The tungsten target plate is analyzed for surface damage using a scanning electron microscope.

  18. Formation and sustainment of field reversed configuration (FRC) plasmas by spheromak merging and neutral beam injection

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Masaaki [Princeton Plasma Physics Laboratory, Princeton University Princeton, New Jersey USA (United States)

    2016-03-25

    This paper briefly reviews a compact toroid reactor concept that addresses critical issues for forming, stabilizing and sustaining a field reversed configuration (FRC) with the use of plasma merging, plasma shaping, conducting shells, neutral beam injection (NBI). In this concept, an FRC plasma is generated by the merging of counter-helicity spheromaks produced by inductive discharges and sustained by the use of neutral beam injection (NBI). Plasma shaping, conducting shells, and the NBI would provide stabilization to global MHD modes. Although a specific FRC reactor design is outside the scope of the present paper, an example of a promising FRC reactor program is summarized based on the previously developed SPIRIT (Self-organized Plasmas by Induction, Reconnection and Injection Techniques) concept in order to connect this concept to the recently achieved the High Performance FRC plasmas obtained by Tri Alpha Energy [Binderbauer et al, Phys. Plasmas 22,056110, (2015)]. This paper includes a brief summary of the previous concept paper by M. Yamada et al, Plasma Fusion Res. 2, 004 (2007) and the recent experimental results from MRX.

  19. Development and application of helicon plasma sources. Evolution of extensive plasma science

    International Nuclear Information System (INIS)

    Shinohara, Shunjiro

    2009-01-01

    Recent advances in plasma science are remarkable, and are deeply indebted to the development of sophisticated plasma sources. While numerous methods have been proposed for producing the plasma, helicon plasma sources, capable of generating high density (>10 13 cm -3 ) plasma with high ionization degree (>several ten percent) over a wide range of external control parameters, have been utilized in such broad areas as fundamental and processing plasmas, nuclear fusion, gas laser, modeling of space plasma, plasma acceleration/propulsion, among others. On the other hand, a number of important issues are left unsolved, in particular, those relevant to the wave phenomena and efficient plasma production. Solution to these issues are expected to play key roles in taking full advantage of the helicon plasma sources in the next generation. In this article, we overview our current understanding of the helicon plasma production and recent development of characteristic helicon plasma sources, and discuss possible future advancement of extensive plasma science utilizing them. (author)

  20. 21 CFR 640.74 - Modification of Source Plasma.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Modification of Source Plasma. 640.74 Section 640...) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Source Plasma § 640.74 Modification of Source Plasma. (a) Upon approval by the Director, Center for Biologics Evaluation and Research, Food and...

  1. The separatrix radius measurement of field-reversed configuration plasma in FRX-L

    International Nuclear Information System (INIS)

    Zhang, Shouyin; Tejero, Erik M.; Taccetti, Jose Martin; Wurden, Glen A.; Intrator, Thomas; Waganaar, William J.

    2004-01-01

    Magnetic pick-up coils and single turn flux loops are installed on the FRX-L device. The combination of the two measurements provides the excluded flux radius that approximates the separatrix radius of the field-reversed configuration plasma. Arrays of similar probes are used to map out local magnetic field dynamics beyond both ends of the theta-coil confinement region to help understand the effects of cusp locations on flux trapping during the FRC formation process. Details on the probe design and system calibrations are presented. The overall system calibration of excluded flux radius measurement is examined by replacing FRC plasma with a known radius aluminum conductor cylinder.

  2. Nonthermal plasmas around black holes, relevant collective modes, new configurations, and magnetic field amplification

    Energy Technology Data Exchange (ETDEWEB)

    Coppi, B., E-mail: coppi@mit.edu [Massachusetts Institute of Technology (United States)

    2017-03-15

    The radiation emission from Shining Black Holes is most frequently observed to have nonthermal features. It is therefore appropriate to consider relevant collective processes in plasmas surrounding black holes that contain high energy particles with nonthermal distributions in momentum space. A fluid description with significant temperature anisotropies is the simplest relevant approach. These anisotropies are shown to have a critical influence on: (a) the existence and characteristics of stationary plasma and field ring configurations, (b) the excitation of “thermo-gravitational modes” driven by temperature anisotropies and gradients that involve gravity and rotation, (c) the generation of magnetic fields over macroscopic scale distances, and (d) the transport of angular momentum.

  3. Magnetic plasma confinement for laser ion source

    International Nuclear Information System (INIS)

    Okamura, M.; Adeyemi, A.; Kanesue, T.; Tamura, J.; Kondo, K.; Dabrowski, R.

    2010-01-01

    A laser ion source (LIS) can easily provide a high current beam. However, it has been difficult to obtain a longer beam pulse while keeping a high current. On occasion, longer beam pulses are required by certain applications. For example, more than 10 μs of beam pulse is required for injecting highly charged beams to a large sized synchrotron. To extend beam pulse width, a solenoid field was applied at the drift space of the LIS at Brookhaven National Laboratory. The solenoid field suppressed the diverging angle of the expanding plasma and the beam pulse was widened. Also, it was observed that the plasma state was conserved after passing through a few hundred gauss of the 480 mm length solenoid field.

  4. Magnetic plasma confinement for laser ion source.

    Science.gov (United States)

    Okamura, M; Adeyemi, A; Kanesue, T; Tamura, J; Kondo, K; Dabrowski, R

    2010-02-01

    A laser ion source (LIS) can easily provide a high current beam. However, it has been difficult to obtain a longer beam pulse while keeping a high current. On occasion, longer beam pulses are required by certain applications. For example, more than 10 micros of beam pulse is required for injecting highly charged beams to a large sized synchrotron. To extend beam pulse width, a solenoid field was applied at the drift space of the LIS at Brookhaven National Laboratory. The solenoid field suppressed the diverging angle of the expanding plasma and the beam pulse was widened. Also, it was observed that the plasma state was conserved after passing through a few hundred gauss of the 480 mm length solenoid field.

  5. Investigation of Capacitively Coupled Argon Plasma Driven by Dual-Frequency with Different Frequency Configurations

    International Nuclear Information System (INIS)

    Yu Yiqing; Xin Yu; Ning Zhaoyuan; Lu Wenqi

    2011-01-01

    Low pressure argon dual-frequency (DF) capacitively coupled plasma (CCP) is generated by using different frequency configurations, such as 13.56/2, 27/2, 41/2, and 60/2 MHz. Characteristics of the plasma are investigated by using a floating double electrical probe and optical emission spectroscopy (OES). It is shown that in the DF-CCPs, the electron temperature T e decreases with the increase in exciting frequency, while the onset of 2 MHz induces a sudden increase in T e and the electron density increases basically with the increase in low frequency (LF) power. The intensity of 750.4 nm emission line increases with the LF power in the case of 13.56/2 MHz, while different tendencies of line intensity with the LF power appear for other configurations. The reason for this is also discussed.

  6. Phase mixing of Alfvén waves in axisymmetric non-reflective magnetic plasma configurations

    Science.gov (United States)

    Petrukhin, N. S.; Ruderman, M. S.; Shurgalina, E. G.

    2018-02-01

    We study damping of phase-mixed Alfvén waves propagating in non-reflective axisymmetric magnetic plasma configurations. We derive the general equation describing the attenuation of the Alfvén wave amplitude. Then we applied the general theory to a particular case with the exponentially divergent magnetic field lines. The condition that the configuration is non-reflective determines the variation of the plasma density along the magnetic field lines. The density profiles exponentially decreasing with the height are not among non-reflective density profiles. However, we managed to find non-reflective profiles that fairly well approximate exponentially decreasing density. We calculate the variation of the total wave energy flux with the height for various values of shear viscosity. We found that to have a substantial amount of wave energy dissipated at the lower corona, one needs to increase shear viscosity by seven orders of magnitude in comparison with the value given by the classical plasma theory. An important result that we obtained is that the efficiency of the wave damping strongly depends on the density variation with the height. The stronger the density decrease, the weaker the wave damping is. On the basis of this result, we suggested a physical explanation of the phenomenon of the enhanced wave damping in equilibrium configurations with exponentially diverging magnetic field lines.

  7. Magnetic configuration effects on plasma transport under Neutral Beam Injection at TJ-II (Simulation)

    International Nuclear Information System (INIS)

    Guasp, J.; Fuentes, C.; Liniers, M.

    2001-01-01

    A systematic analysis of magnetic configurations (27 in total), using a Transport model including impurity dynamics and sputtering effects has been done. For small size configurations or those close to rational t values there is radioactive collapse, independently of the external gas puffing (GP) strategy chosen. The reason is the insufficiency of observed power, either by the high shine through losses due to their low radii, or by the increase of fast ion orbit losses near the resonances. For the majority of configurations without collapse, fast ion orbit losses for CO injection (going in the same direction than the toroidal magnetic field) are higher, and in consequence the power absorption and the plasma β achieved are laser, than for the opposite direction. Nevertheless in the region placed just above the main resonances (1/3 and 1/2 per period) this situation reverses. The reasons have been analysed and explained at previous studies. A consequence of this fact is that the optima of confinement for the Counter case are shifted towards higher t values than the CO one, with higher plasma β, except near the resonances. As usual the balanced case is in between. The optima achieving stationary state are very close (and often are coincident) with those lacking that restriction. The best configuration (highest average β for balanced injection, with =1.1% and central value 3.2%, although in this region the results are rather insensitive to configuration and GP strategy. the configurations placed around the 100 4 4 would need also the lowest power entering the torus in order to avoid collapse and to achieve an acceptable NBI absorption level. (Author) 12 refs

  8. A study on the fusion reactor - Numerical analyses of MHD equilibrium and= edge plasma transport in tokamak fusion reactor with divertor configurations

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Sang Hee; Kang, Kyung Doo; Ryu, Ji Myung; Kim, Deok Kyu; Chung, TaeKyun; Chung, Mo Se [Seoul National University, Seoul (Korea, Republic of); Cho, Su Won [Kyungki University, Suwon (Korea, Republic of)

    1995-08-01

    In the present project for developing the numerical codes of 2-D MHD equilibrium, edge plasma transport and neutral particle transport for the tokamak plasmas, we computed the MHD equilibria of single and double null configurations and determined the external coil currents and the plasma parameters used for operation and control data. Also we numerically acquired the distributions of edge plasma parameters in poloidal and radial directions= and the design-related values according to the various operating conditions using the developed plasma transport code. Furthermore, a neutral particle transport code for the edge region is developed and them used for the analysis of the neutral particle behavior yielding the source terms in the fluid transport equations, and expected to supply the input parameters for the edge plasma transport code. 53 refs., 12 tabs., 44 figs. (author)

  9. Design and optimization of components and processes for plasma sources in advanced material treatments

    OpenAIRE

    Rotundo, Fabio

    2012-01-01

    The research activities described in the present thesis have been oriented to the design and development of components and technological processes aimed at optimizing the performance of plasma sources in advanced in material treatments. Consumables components for high definition plasma arc cutting (PAC) torches were studied and developed. Experimental activities have in particular focussed on the modifications of the emissive insert with respect to the standard electrode configuration, whi...

  10. Combustion flame-plasma hybrid reactor systems, and chemical reactant sources

    Science.gov (United States)

    Kong, Peter C

    2013-11-26

    Combustion flame-plasma hybrid reactor systems, chemical reactant sources, and related methods are disclosed. In one embodiment, a combustion flame-plasma hybrid reactor system comprising a reaction chamber, a combustion torch positioned to direct a flame into the reaction chamber, and one or more reactant feed assemblies configured to electrically energize at least one electrically conductive solid reactant structure to form a plasma and feed each electrically conductive solid reactant structure into the plasma to form at least one product is disclosed. In an additional embodiment, a chemical reactant source for a combustion flame-plasma hybrid reactor comprising an elongated electrically conductive reactant structure consisting essentially of at least one chemical reactant is disclosed. In further embodiments, methods of forming a chemical reactant source and methods of chemically converting at least one reactant into at least one product are disclosed.

  11. Ohm close-quote s law for plasmas in reversed field pinch configuration

    International Nuclear Information System (INIS)

    Martines, E.; Vallone, F.

    1997-01-01

    An analytical relationship between current density and applied electric field in reversed field pinch (RFP) plasmas has been derived in the framework of the kinetic dynamo theory, that is assuming a radial field-aligned momentum transport caused by the magnetic field stochasticity. This Ohm close-quote s law yields current density profiles with a poloidal current density at the edge which can sustain the magnetic field configuration against resistive diffusion. The dependence of the loop voltage on plasma current and other plasma parameters for RFP experiments has been obtained. The results of the theoretical work have been compared with experimental data from the RFX experiment, and a good agreement has been found. copyright 1997 The American Physical Society

  12. Rethermalization of a field-reversed configuration plasma in translation experiments

    International Nuclear Information System (INIS)

    Himura, H.; Okada, S.; Sugimoto, S.; Goto, S.

    1995-01-01

    A translation experiment of field-reversed configuration (FRC) plasma is performed on the FIX machine [Shiokawa and Goto, Phys. Fluids B 5, 534 (1993)]. The translated FRC bounces between magnetic mirror fields at both ends of a confinement region. The plasma loses some of its axial kinetic energy when it is reflected by the magnetic mirror field, and eventually settles down in the confinement region. In this reflection process, the plasma temperature rises significantly. Such plasma rethermalization has been observed in OCT-L1 experiments [Ito et al., Phys. Fluids 30, 168 (1987)], but rarely in FRX-C/T experiments [Rej et al., Phys. Fluids 29, 852 (1986)]. It is found that the rethermalization depends on the relation between the plasma temperature and the translation velocity. The rethermalization occurs only in the case where the translation velocity exceeds the sound velocity. This result implies the rethermalization is caused by a shock wave induced within the FRC when the plasma is reflected by the magnetic mirror field. copyright 1995 American Institute of Physics

  13. Profile formation and sustainment of autonomous tokamak plasma with current hole configuration

    International Nuclear Information System (INIS)

    Hayashi, N.; Takizuka, T.; Ozeki, T.

    2005-01-01

    We have investigated the profile formation and sustainment of tokamak plasmas with the current hole (CH) configuration by using 1.5D time-dependent transport simulations. A model of the current limit inside the CH on the basis of the Axisymmetric Tri-Magnetic-Islands equilibrium is introduced into the transport simulation. We found that a transport model with the sharp reduction of anomalous transport in the reversed-shear (RS) region can reproduce the time evolution of profiles observed in JT-60U experiments. The transport becomes neoclassical-level in the RS region, which results in the formation of profiles with internal transport barrier (ITB) and CH. The CH plasma has an autonomous property because of the strong interaction between a pressure profile and a current profile through the large bootstrap current fraction. The ITB width determined by the neoclassical-level transport agrees well with that measured in JT-60U. The energy confinement inside the ITB agrees with the scaling based on the JT-60U data. The scaling means the autonomous limitation of energy confinement in the CH plasma. The plasma with the large CH is sustained with the full current drive by the bootstrap current. The plasma with the small CH and the small bootstrap current fraction shrinks due to the penetration of inductive current. This shrink is prevented and the CH size can be controlled by the appropriate external current drive (CD). The CH plasma is found to respond autonomically to the external CD. (author)

  14. Inertial electro-magnetostatic plasma neutron sources

    International Nuclear Information System (INIS)

    Barnes, D.C.; Nebel, R.A.; Schauer, M.M.; Pickrel, M.M.

    1997-01-01

    Two types of systems are being studied experimentally as D-T plasma neutron sources. In both concepts, spherical convergence of either electrons or ions or both is used to produce a dense central focus within which D-T fusion reactions produce 14 MeV neutrons. One concept uses nonneutral plasma confinement principles in a Penning type trap. In this approach, combined electrostatic and magnetic fields provide a vacuum potential well within which electrons are confined and focused. A small (6 mm radius) spherical machine has demonstrated a focus of 30 microm radius, with a central density of up to 35 times the Brillouin density limit of a static trap. The resulting electron plasma of up to several 10 13 cm -3 provides a multi-kV electrostatic well for confining thermonuclear ions as a neutron source. The second concept (Inertial Electrostatic Confinement, or IEC) uses a high-transparence grid to form a global well for acceleration and confinement of ions. Such a system has demonstrated steady neutron output of 2 x 10 10 s -1 . The present experiment will scale this to >10 11 s -1 . Advanced designs based on each concept have been developed recently. In these proposed approaches, a uniform-density electron sphere forms an electrostatic well for ions. Ions so trapped may be focused by spherical convergence to produce a dense core. An alternative approach produces large amplitude spherical oscillations of a confined ion cloud by a small, resonant modulation of the background electrons. In both the advanced Penning trap approach and the advanced IEC approach, the electrons are magnetically insulated from a large (up to 100 kV) applied electrostatic field. The physics of these devices is discussed, experimental design details are given, present observations are analyzed theoretically, and the performance of future advanced systems are predicted

  15. Plasma Processing of Metallic and Semiconductor Thin Films in the Fisk Plasma Source

    Science.gov (United States)

    Lampkin, Gregory; Thomas, Edward, Jr.; Watson, Michael; Wallace, Kent; Chen, Henry; Burger, Arnold

    1998-01-01

    The use of plasmas to process materials has become widespread throughout the semiconductor industry. Plasmas are used to modify the morphology and chemistry of surfaces. We report on initial plasma processing experiments using the Fisk Plasma Source. Metallic and semiconductor thin films deposited on a silicon substrate have been exposed to argon plasmas. Results of microscopy and chemical analyses of processed materials are presented.

  16. A high-current pulsed cathodic vacuum arc plasma source

    International Nuclear Information System (INIS)

    Oates, T.W.H.; Pigott, J.; Mckenzie, D.R.; Bilek, M.M.M.

    2003-01-01

    Cathodic vacuum arcs (CVAs) are well established as a method for producing metal plasmas for thin film deposition and as a source of metal ions. Fundamental differences exist between direct current (dc) and pulsed CVAs. We present here results of our investigations into the design and construction of a high-current center-triggered pulsed CVA. Power supply design based on electrolytic capacitors is discussed and optimized based on obtaining the most effective utilization of the cathode material. Anode configuration is also discussed with respect to the optimization of the electron collection capability. Type I and II cathode spots are observed and discussed with respect to cathode surface contamination. An unfiltered deposition rate of 1.7 nm per pulse, at a distance of 100 mm from the source, has been demonstrated. Instantaneous plasma densities in excess of 1x10 19 m -3 are observed after magnetic filtering. Time averaged densities an order of magnitude greater than common dc arc densities have been demonstrated, limited by pulse repetition rate and filter efficiency

  17. Penning plasma based simultaneous light emission source of visible and VUV lights

    Energy Technology Data Exchange (ETDEWEB)

    Vyas, G. L., E-mail: glvyas27@gmail.com [Manipal University Jaipur (India); Prakash, R.; Pal, U. N. [CSIR-Central Electronics and Engineering Research Institute, Microwave Tubes Division (India); Manchanda, R. [Institute for Plasma Research (India); Halder, N. [Manipal University Jaipur (India)

    2016-06-15

    In this paper, a laboratory-based penning plasma discharge source is reported which has been developed in two anode configurations and is able to produce visible and VUV lights simultaneously. The developed source has simultaneous diagnostics facility using Langmuir probe and optical emission spectroscopy. The two anode configurations, namely, double ring and rectangular configurations, have been studied and compared for optimum use of the geometry for efficient light emissions and recording. The plasma is produced using helium gas and admixture of three noble gases including helium, neon, and argon. The source is capable to produce eight spectral lines for pure helium in the VUV range from 20 to 60 nm and total 24 spectral lines covering the wavelength range 20–106 nm for the admixture of gases. The large range of VUV lines is generated from gaseous admixture rather from the sputtered materials. The recorded spectrum shows that the plasma light radiations in both visible and VUV range are larger in double ring configuration than that of the rectangular configurations at the same discharge operating conditions. To clearly understand the difference, the imaging of the discharge using ICCD camera and particle-in-cell simulation using VORPAL have also been carried out. The effect of ion diffusion, metastable collision with the anode wall and the nonlinear effects are correlated to explain the results.

  18. Dense Plasma Focus - From Alternative Fusion Source to Versatile High Energy Density Plasma Source for Plasma Nanotechnology

    Science.gov (United States)

    Rawat, R. S.

    2015-03-01

    The dense plasma focus (DPF), a coaxial plasma gun, utilizes pulsed high current electrical discharge to heat and compress the plasma to very high density and temperature with energy densities in the range of 1-10 × 1010 J/m3. The DPF device has always been in the company of several alternative magnetic fusion devices as it produces intense fusion neutrons. Several experiments conducted on many different DPF devices ranging over several order of storage energy have demonstrated that at higher storage energy the neutron production does not follow I4 scaling laws and deteriorate significantly raising concern about the device's capability and relevance for fusion energy. On the other hand, the high energy density pinch plasma in DPF device makes it a multiple radiation source of ions, electron, soft and hard x-rays, and neutrons, making it useful for several applications in many different fields such as lithography, radiography, imaging, activation analysis, radioisotopes production etc. Being a source of hot dense plasma, strong shockwave, intense energetic beams and radiation, etc, the DPF device, additionally, shows tremendous potential for applications in plasma nanoscience and plasma nanotechnology. In the present paper, the key features of plasma focus device are critically discussed to understand the novelties and opportunities that this device offers in processing and synthesis of nanophase materials using, both, the top-down and bottom-up approach. The results of recent key experimental investigations performed on (i) the processing and modification of bulk target substrates for phase change, surface reconstruction and nanostructurization, (ii) the nanostructurization of PLD grown magnetic thin films, and (iii) direct synthesis of nanostructured (nanowire, nanosheets and nanoflowers) materials using anode target material ablation, ablated plasma and background reactive gas based synthesis and purely gas phase synthesis of various different types of

  19. Dense Plasma Focus - From Alternative Fusion Source to Versatile High Energy Density Plasma Source for Plasma Nanotechnology

    International Nuclear Information System (INIS)

    Rawat, R S

    2015-01-01

    The dense plasma focus (DPF), a coaxial plasma gun, utilizes pulsed high current electrical discharge to heat and compress the plasma to very high density and temperature with energy densities in the range of 1-10 × 10 10 J/m 3 . The DPF device has always been in the company of several alternative magnetic fusion devices as it produces intense fusion neutrons. Several experiments conducted on many different DPF devices ranging over several order of storage energy have demonstrated that at higher storage energy the neutron production does not follow I 4 scaling laws and deteriorate significantly raising concern about the device's capability and relevance for fusion energy. On the other hand, the high energy density pinch plasma in DPF device makes it a multiple radiation source of ions, electron, soft and hard x-rays, and neutrons, making it useful for several applications in many different fields such as lithography, radiography, imaging, activation analysis, radioisotopes production etc. Being a source of hot dense plasma, strong shockwave, intense energetic beams and radiation, etc, the DPF device, additionally, shows tremendous potential for applications in plasma nanoscience and plasma nanotechnology. In the present paper, the key features of plasma focus device are critically discussed to understand the novelties and opportunities that this device offers in processing and synthesis of nanophase materials using, both, the top-down and bottom-up approach. The results of recent key experimental investigations performed on (i) the processing and modification of bulk target substrates for phase change, surface reconstruction and nanostructurization, (ii) the nanostructurization of PLD grown magnetic thin films, and (iii) direct synthesis of nanostructured (nanowire, nanosheets and nanoflowers) materials using anode target material ablation, ablated plasma and background reactive gas based synthesis and purely gas phase synthesis of various different types of

  20. Plasma sources for EUV lithography exposure tools

    International Nuclear Information System (INIS)

    Banine, Vadim; Moors, Roel

    2004-01-01

    The source is an integral part of an extreme ultraviolet lithography (EUVL) tool. Such a source, as well as the EUVL tool, has to fulfil extremely high demands both technical and cost oriented. The EUVL tool operates at a wavelength in the range 13-14 nm, which requires a major re-thinking of state-of-the-art lithography systems operating in the DUV range. The light production mechanism changes from conventional lamps and lasers to relatively high temperature emitting plasmas. The light transport, mainly refractive for DUV, should become reflective for EUV. The source specifications are derived from the customer requirements for the complete tool, which are: throughput, cost of ownership (CoO) and imaging quality. The EUVL system is considered as a follow up of the existing DUV based lithography technology and, while improving the feature resolution, it has to maintain high wafer throughput performance, which is driven by the overall CoO picture. This in turn puts quite high requirements on the collectable in-band power produced by an EUV source. Increased, due to improved feature resolution, critical dimension (CD) control requirements, together with reflective optics restrictions, necessitate pulse-to-pulse repeatability, spatial stability control and repetition rates, which are substantially better than those of current optical systems. All together the following aspects of the source specification will be addressed: the operating wavelength, the EUV power, the hot spot size, the collectable angle, the repetition rate, the pulse-to-pulse repeatability and the debris induced lifetime of components

  1. Measurements of Plasma Power Losses in the C-2 Field-Reversed Configuration Experiment

    Science.gov (United States)

    Korepanov, Sergey; Smirnov, Artem; Garate, Eusebio; Donin, Alexandr; Kondakov, Alexey; Singatulin, Shavkat

    2013-10-01

    A high-confinement operating regime with plasma lifetimes significantly exceeding past empirical scaling laws was recently obtained by combining plasma gun edge biasing and tangential Neutral Beam Injection in the C-2 field-reversed configuration (FRC) experiment. To analyze the power balance in C-2, two new diagnostic instruments - the pyroelectric (PE) and infrared (IR) bolometers - were developed. The PE bolometer, designed to operate in the incident power density range from 0.1-100 W/cm2, is used to measure the radial power loss, which is dominated by charge-exchange neutrals and radiation. The IR bolometer, which measures power irradiated onto a thin metal foil inserted in the plasma, is designed for the power density range from 0.5-5 kW/cm2. The IR bolometer is used to measure the axial power loss from the plasma near the end divertors. The maximum measurable pulse duration of ~ 10 ms is limited by the heat capacitance of the IR detector. Both detectors have time resolution of about 10-100 μs and were calibrated in absolute units using a high power neutral beam. We present the results of first direct measurements of axial and radial plasma power losses in C-2.

  2. Plasma focus - a pulsed radiation source

    International Nuclear Information System (INIS)

    Blagoev, Alexandar; Zapryanov, Stanislav; Gol'tsev, Vasilii; Gemishev, Orlin

    2014-01-01

    The article is devoted to the applications of plasma focus (PF) in radiobiology. Briefly describes the principle of operation of the device and the parameters of the PF type 'Mader' at the Physics Department of the University. Phase pinch discharge zones appear hot and dense plasma, which is a source of X-ray and neutron pulse when the working gas is deuterium. These radiations are essential for biological applications. Besides these bundles are obtained from accelerated charged particles and shock wave of ionized gas. Described are some of the contributions of other authors using PF in radiobiology. Given the results in the exposure of living organisms with soft X-ray emission of PF. We examined the viability of the cells of the two types of yeasts, after irradiation with X-rays at a dose of 65 mSv, where no change was found on the performance. It is shown that soft X-ray radiation doses on the order of tens of mSv, cause a significant change in the productivity of the electronic transport in the photosynthetic apparatus of Chlamydomonas reinhardtii. Trichoderma reesei M7 shows remarkable vitality irradiation with substantial doses of hard X-ray radiation (tens Sv). Appear endoglyukonazata changes in the protein component and the residual mass

  3. High electronegativity multi-dipolar electron cyclotron resonance plasma source for etching by negative ions

    DEFF Research Database (Denmark)

    Stamate, Eugen; Draghici, M.

    2012-01-01

    A large area plasma source based on 12 multi-dipolar ECR plasma cells arranged in a 3 x 4 matrix configuration was built and optimized for silicon etching by negative ions. The density ratio of negative ions to electrons has exceeded 300 in Ar/SF6 gas mixture when a magnetic filter was used...... to reduce the electron temperature to about 1.2 eV. Mass spectrometry and electrostatic probe were used for plasma diagnostics. The new source is free of density jumps and instabilities and shows a very good stability for plasma potential, and the dominant negative ion species is F-. The magnetic field...... in plasma volume is negligible and there is no contamination by filaments. The etching rate by negative ions measured in Ar/SF6/O-2 mixtures was almost similar with that by positive ions reaching 700 nm/min. (C) 2012 American Institute of Physics...

  4. Inductively coupled plasma source mass spectrometry

    International Nuclear Information System (INIS)

    Price Russ, G. III

    1993-01-01

    Inductively coupled plasma source mass spectrometry (ICP-MS) is a relatively new (5 y commercial availability) technique for simultaneously determining the concentration and isotopic composition of a large number of elements at trace levels. The principle advantages of ICP-MS are the ability to measure essentially all the metallic elements at concentrations as low as 1 part in 10 12 by weight, to analyse aqueous samples directly, to determine the isotopic composition of essentially all the metallic elements, and to analyse samples rapidly (minutes). The history of the development of ICP-MS and discussions of a variety of applications have been discussed in detail in Date and Gray (1988). Koppenaal (1988, 1990) has reviewed the ICP-MS literature. In that ICP-MS is a relatively new and still evolving technique, this chapter will discuss potential capability more than proven performance. (author). 24 refs

  5. Analysis of magnetic-dipole transitions in tungsten plasmas using detailed and configuration-average descriptions

    Science.gov (United States)

    Na, Xieyu; Poirier, Michel

    2017-06-01

    This paper is devoted to the analysis of transition arrays of magnetic-dipole (M1) type in highly charged ions. Such transitions play a significant role in highly ionized plasmas, for instance in the tungsten plasma present in tokamak devices. Using formulas recently published and their implementation in the Flexible Atomic Code for M1-transition array shifts and widths, absorption and emission spectra arising from transitions inside the 3*n complex of highly-charged tungsten ions are analyzed. A comparison of magnetic-dipole transitions with electric-dipole (E1) transitions shows that, while the latter are better described by transition array formulas, M1 absorption and emission structures reveal some insufficiency of these formulas. It is demonstrated that the detailed spectra account for significantly richer structures than those predicted by the transition array formalism. This is due to the fact that M1 transitions may occur between levels inside the same relativistic configuration, while such inner configuration transitions are not accounted for by the currently available averaging expression. In addition, because of configuration interaction, transition processes involving more than one electron jump, such as 3p1/23d5/2 → 3p3/23d3/2, are possible but not accounted for in the transition array formulas. These missing transitions are collected in pseudo-arrays using a post-processing method described in this paper. The relative influence of inner- and inter-configuration transitions is carefully analyzed in cases of tungsten ions with net charge around 50. The need for an additional theoretical development is emphasized.

  6. Implosive Thermal Plasma Source for Energy Conversion

    Czech Academy of Sciences Publication Activity Database

    Šonský, Jiří; Tesař, Václav; Gruber, Jan; Mašláni, Alan

    2017-01-01

    Roč. 4, č. 1 (2017), s. 87-90 ISSN 2336-2626 Institutional support: RVO:61388998 ; RVO:61389021 Keywords : implosion * thermal plasma * detonation wave Subject RIV: BL - Plasma and Gas Discharge Physics; BL - Plasma and Gas Discharge Physics (UFP-V) OBOR OECD: Fluids and plasma physics (including surface physics); Fluids and plasma physics (including surface physics) (UFP-V) https://ppt.fel.cvut.cz/ppt2017.html#number1

  7. Operations manual for the plasma source ion implantation economics program

    International Nuclear Information System (INIS)

    Bibeault, M.L.; Thayer, G.R.

    1995-10-01

    Plasma Source Ion Implantation (PSII) is a surface modification technique for metal. PSIICOSTMODEL95 is an EXCEL-based program that estimates the cost for implementing a PSII system in a manufacturing setting where the number of parts to be processed is over 5,000 parts per day and the shape of each part does not change from day to day. Overall, the manufacturing process must be very well defined and should not change. This document is a self-contained manual for PSIICOSTMODEL95. It assumes the reader has some general knowledge of the technical requirements for PSII. Configuration of the PSII process versus design is used as the methodology in PSIICOSTMODEL95. The reason behind this is twofold. First, the design process cannot be programmed into a computer when the relationships between design variables are not understood. Second, the configuration methodology reduces the number of assumptions that must be programmed into our software. Misuse of results are less likely to occur if the user has fewer assumptions to understand

  8. End-shorting and electric field in edge plasmas with application to field-reversed configurations

    International Nuclear Information System (INIS)

    Steinhauer, Loren C.

    2002-01-01

    The shorting of open field lines where they intersect external boundaries strongly modifies the transverse electric field all along the field lines. The modified electric field is found by an extension of the familiar Boltzmann relation for the electric potential. This leads to a prediction of the electric drift. Flow generation by electrical shorting is applied here to three aspects of elongated field-reversed configurations: plasma rotation rate; the particle-loss spin-up mechanism; and the sustainability of the rotating magnetic field current drive method

  9. Plasma-gun-assisted field-reversed configuration formation in a conical θ-pinch

    Energy Technology Data Exchange (ETDEWEB)

    Weber, T. E., E-mail: tweber@lanl.gov; Intrator, T. P. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Smith, R. J. [Department of Aeronautics and Astronautics, University of Washington, Seattle, Washington 98195 (United States)

    2015-04-15

    Injection of plasma via an annular array of coaxial plasma guns during the pre-ionization phase of field-reversed configuration (FRC) formation is shown to catalyze the bulk ionization of a neutral gas prefill in the presence of a strong axial magnetic field and change the character of outward flux flow during field-reversal from a convective process to a much slower resistive diffusion process. This approach has been found to significantly improve FRC formation in a conical θ-pinch, resulting in a ∼350% increase in trapped flux at typical operating conditions, an expansion of accessible formation parameter space to lower densities and higher temperatures, and a reduction or elimination of several deleterious effects associated with the pre-ionization phase.

  10. Plasma-gun-assisted field-reversed configuration formation in a conical θ-pinch

    Science.gov (United States)

    Weber, T. E.; Intrator, T. P.; Smith, R. J.

    2015-04-01

    Injection of plasma via an annular array of coaxial plasma guns during the pre-ionization phase of field-reversed configuration (FRC) formation is shown to catalyze the bulk ionization of a neutral gas prefill in the presence of a strong axial magnetic field and change the character of outward flux flow during field-reversal from a convective process to a much slower resistive diffusion process. This approach has been found to significantly improve FRC formation in a conical θ-pinch, resulting in a ˜350% increase in trapped flux at typical operating conditions, an expansion of accessible formation parameter space to lower densities and higher temperatures, and a reduction or elimination of several deleterious effects associated with the pre-ionization phase.

  11. Experimental study on highly collisional edge plasmas in W7-AS island divertor configurations

    International Nuclear Information System (INIS)

    Grigull, P.; Hildebrandt, D.; Sardei, F.; Feng, Y.; Herre, G.; Herrmann, A.; Hofmann, J.V.; Kisslinger, J.; Kuehner, G.; Niedermeyer, H.; Schneider, R.; Verbeek, H.; Wagner, F.; Wolf, R.; Zhang, X.D.

    1997-01-01

    Edge plasma scenarios in island divertor configurations ('natural' magnetic islands intersected by targets) are studied by comparing data from moderate to high density NBI discharges with 3D code (EMC3/EIRENE) results. The data strongly indicate that high recycling with significant particle flux enhancement was achieved in this geometry. But, plasma pressure losses towards the targets are relatively strong, and high recycling sets in only at n e >10 20 m -3 . The respective density enhancement in front of the targets is moderate (up to a factor of about three relative to the upstream density). These scenarios are also in basic agreement with B2/EIRENE code predictions. At n e >1.5 x 10 20 m -3 detachment seems to develop. Improvements are expected from additional coils controlling the field line pitch inside the islands, and from optimized targets which will better focus recycling neutrals into the islands. Both are in preparation. (orig.)

  12. Brachytherapy Partial Breast Irradiation: Analyzing Effect of Source Configurations on Dose Metrics Relevant to Toxicity

    International Nuclear Information System (INIS)

    Cormack, Robert A.; Devlin, Phillip M.

    2008-01-01

    Purpose: Recently, the use of partial breast irradiation (PBI) for patients with early-stage breast cancer with low-risk factors has increased. The volume of the high-dose regions has been correlated with toxicity in interstitial treatment. Although no such associations have been made in applicator-based experience, new applicators are being developed that use complex noncentered source configurations. This work studied the effect of noncentered source placements on the volume of the high-dose regions around a spherical applicator. Methods and Materials: Many applicator configurations were numerically simulated for a range of inflation radii. For each configuration, a dose homogeneity index was used as a dose metric to measure the volume of the high-dose region. Results: All multisource configurations examined resulted in an increase of the high-dose region compared with a single-center source. The resulting decrease in the prescription dose homogeneity index was more pronounced for sources further from the center of the applicator, and the effect was reduced as the number of dwell locations was increased. Conclusion: The geometries of particular applicators were not considered to achieve a more general result. On the basis of the calculations of this work, it would appear that treatment using noncentered dwell locations will lead to an increase in the volume of the high-dose regions

  13. Monte Carlo simulation of a TRIGA source driven core configuration: Preliminary results

    International Nuclear Information System (INIS)

    Burgio, N.; Ciavola, C.; Santagata, A.

    2002-01-01

    The different core configurations with a k eff ranging from 0.93 to 0.98, and their response when driven by a pulsed neutron source were simulated with MCNP4C3 (Los Alamos - Monte Carlo N Particles). Simulation results could be considered both as preliminary check for nuclear data and a conceptual design for 'source jerk' experiments on the frame of TRIGA Accelerator Driven Experiment (TRADE) on the reactor facility of Casaccia research center. (author)

  14. Computerized study of several electrostatic, surface-ionization ion-source configurations

    Energy Technology Data Exchange (ETDEWEB)

    Balestrini, S.J.; Schuster, B.G.

    1984-08-01

    A computer-based method is presented whereby the optics of electrostatic, surface-ionization ion-source designs can be analyzed theoretically. The analysis solves for the luminosity and disperstion of a beam of charged particles at the final collimating slit and at locations preceding the slit. The performance of an ion source tested in 1960 and also some newer optical configurations are compared with theory.

  15. Measurement of performance parameters of plasma source for plasma opening switch on Qiangguang-Ⅰ generator

    International Nuclear Information System (INIS)

    Luo Weixi; Zeng Zhengzhong; Lei Tianshi; Wang Liangping; Hu Yixiang; Sun Tieping; Huang Tao

    2012-01-01

    The plasma source (cable guns) of the plasma opening switch (POS) on Qiangguang Ⅰ generator was chosen as the study object. The plasma source performance was investigated by using charge collectors. Experimental results show that the plasma ejection density is positively correlated with the structural parameter, the distance between gun core tip and muzzle plane, and the plasma ejection velocity is negatively correlated with the parameter. The increasing rate of plasma ejection density is less than that of drive current. As far as a plasma source with tens of cable plasma guns is concerned, the influence of single cable gun's discharge dispersancy on plasma uniformity is little. Analysis of uncertainty shows that the uncertainty of measurement can be reduced by increasing the number of experiments and averaging the results. The combined standard uncertainty of plasma ejection density is less than 10%. (authors)

  16. Towards easing the configuration and new team member accommodation for open source software based portals

    Science.gov (United States)

    Fu, L.; West, P.; Zednik, S.; Fox, P. A.

    2013-12-01

    For simple portals such as vocabulary based services, which contain small amounts of data and require only hyper-textual representation, it is often an overkill to adopt the whole software stack of database, middleware and front end, or to use a general Web development framework as the starting point of development. Directly combining open source software is a much more favorable approach. However, our experience with the Coastal and Marine Spatial Planning Vocabulary (CMSPV) service portal shows that there are still issues such as system configuration and accommodating a new team member that need to be handled carefully. In this contribution, we share our experience in the context of the CMSPV portal, and focus on the tools and mechanisms we've developed to ease the configuration job and the incorporation process of new project members. We discuss the configuration issues that arise when we don't have complete control over how the software in use is configured and need to follow existing configuration styles that may not be well documented, especially when multiple pieces of such software need to work together as a combined system. As for the CMSPV portal, it is built on two pieces of open source software that are still under rapid development: a Fuseki data server and Epimorphics Linked Data API (ELDA) front end. Both lack mature documentation and tutorials. We developed comparison and labeling tools to ease the problem of system configuration. Another problem that slowed down the project is that project members came and went during the development process, so new members needed to start with a partially configured system and incomplete documentation left by old members. We developed documentation/tutorial maintenance mechanisms based on our comparison and labeling tools to make it easier for the new members to be incorporated into the project. These tools and mechanisms also provided benefit to other projects that reused the software components from the CMSPV

  17. Plasma grid design for optimized filter field configuration for the NBI test facility ELISE

    International Nuclear Information System (INIS)

    Nocentini, R.; Gutser, R.; Heinemann, B.; Froeschle, M.; Riedl, R.

    2009-01-01

    Maintenance-free RF sources for negative hydrogen ions with moderate extraction areas (100-200 cm 2 ) have been successfully developed in the last years at IPP Garching in the test facilities BATMAN and MANITU. A facility with larger extraction area (1000 cm 2 ), ELISE, is being designed with a 'half-size' ITER-like extraction system, pulsed ion acceleration up to 60 kV for 10 s and plasma generation up to 1 h. Due to the large size of the source, the magnetic filter field (FF) cannot be produced solely by permanent magnets. Therefore, an additional magnetic field produced by current flowing through the plasma grid (PG current) is required. The filter field homogeneity and the interaction with the electron suppression magnetic field have been studied in detail by finite element method (FEM) during the ELISE design phase. Significant improvements regarding the field homogeneity have been introduced compared to the ITER reference design. Also, for the same PG current a 50% higher field in front of the grid has been achieved by optimizing the plasma grid geometry. Hollow spaces have been introduced in the plasma grid for a more homogeneous PG current distribution. The introduction of hollow spaces also allows the insertion of permanent magnets in the plasma grid.

  18. A Brief Study on the Ignition of the Non-Thermal Atmospheric Pressure Plasma Jet from a Double Dielectric Barrier Configured Plasma Pencil

    International Nuclear Information System (INIS)

    Begum, Asma; Laroussi, Mounir; Pervez, M. R.

    2013-01-01

    To understand the self sustained propagation of the plasma jet/bullet in air under atmospheric pressure, the ignition of the plasma jet/bullet, the plasma jet/bullet ignition point in the plasma pencil, the formation time and the formation criteria from a dielectric barrier configured plasma pencil were investigated in this study. The results were confirmed by comparing these results with the plasma jet ignition process in the plasma pencil without a dielectric barrier. Electrical, optical, and imaging techniques were used to study the formation of the plasma jet from the ignition of discharge in a double dielectric barrier configured plasma pencil. The investigation results show that the plasma jet forms at the outlet of the plasma pencil as a donut shaped discharge front because of the electric field line along the outlet's surface. It is shown that the required time for the formation of the plasma jet changes with the input voltage of the discharge. The input power calculation for the gap discharge and for the whole system shows that 56% of the average input power is used by the first gap discharge. The estimated electron density inside the gap discharge is in the order of 10 11 cm −3 . If helium is used as a feeding gas, a minimum 1.48×10 −8 C charge is required per pulse in the gap discharge to generate a plasma jet

  19. Experimental facility for determining plasma characteristics in ion sources

    International Nuclear Information System (INIS)

    Abroyan, M.A.; Kagan, Yu.M.; Kolokolov, N.B.; Lavrov, B.P.

    A facility for optical and electrical measurements of the plasma parameters in the arc plasma ion sources is described. The potentialities of the system are demonstrated on the basis of the electron concentration, the electron energy distribution function, and the radial population distribution of the excited states of hydrogen atoms in the arc plasma of the duoplasmatron. (U.S.)

  20. Analysis of the tuning characteristics of microwave plasma source

    Energy Technology Data Exchange (ETDEWEB)

    Miotk, Robert, E-mail: rmiotk@imp.gda.pl; Jasiński, Mariusz [Centre for Plasma and Laser Engineering, The Szewalski Institute of Fluid-Flow Machinery, Polish Academy of Sciences, Fiszera 14, 80-231 Gdańsk (Poland); Mizeraczyk, Jerzy [Department of Marine Electronics, Gdynia Maritime University, Morska 81-87, 81-225 Gdynia (Poland)

    2016-04-15

    In this paper, we present an analysis of the tuning characteristics of waveguide-supplied metal-cylinder-based nozzleless microwave plasma source. This analysis has enabled to estimate the electron concentration n{sub e} and electron frequency collisions ν in the plasma generated in nitrogen and in a mixture of nitrogen and ethanol vapour. The parameters n{sub e} and ν are the basic quantities that characterize the plasma. The presented new plasma diagnostic method is particularly useful, when spectroscopic methods are useless. The presented plasma source is currently used in research of a hydrogen production from liquids.

  1. Analysis of the tuning characteristics of microwave plasma source

    International Nuclear Information System (INIS)

    Miotk, Robert; Jasiński, Mariusz; Mizeraczyk, Jerzy

    2016-01-01

    In this paper, we present an analysis of the tuning characteristics of waveguide-supplied metal-cylinder-based nozzleless microwave plasma source. This analysis has enabled to estimate the electron concentration n_e and electron frequency collisions ν in the plasma generated in nitrogen and in a mixture of nitrogen and ethanol vapour. The parameters n_e and ν are the basic quantities that characterize the plasma. The presented new plasma diagnostic method is particularly useful, when spectroscopic methods are useless. The presented plasma source is currently used in research of a hydrogen production from liquids.

  2. Kinetic description of quasi-stationary axisymmetric collisionless accretion disk plasmas with arbitrary magnetic field configurations

    International Nuclear Information System (INIS)

    Cremaschini, Claudio; Miller, John C.; Tessarotto, Massimo

    2011-01-01

    A kinetic treatment is developed for collisionless magnetized plasmas occurring in high-temperature, low-density astrophysical accretion disks, such as are thought to be present in some radiatively inefficient accretion flows onto black holes. Quasi-stationary configurations are investigated, within the framework of a Vlasov-Maxwell description. The plasma is taken to be axisymmetric and subject to the action of slowly time-varying gravitational and electromagnetic fields. The magnetic field is assumed to be characterized by a family of locally nested but open magnetic surfaces. The slow collisionless dynamics of these plasmas is investigated, yielding a reduced gyrokinetic Vlasov equation for the kinetic distribution function. For doing this, an asymptotic quasi-stationary solution is first determined, represented by a generalized bi-Maxwellian distribution expressed in terms of the relevant adiabatic invariants. The existence of the solution is shown to depend on having suitable kinetic constraints and conditions leading to particle trapping phenomena. With this solution, one can treat temperature anisotropy, toroidal and poloidal flow velocities, and finite Larmor-radius effects. An asymptotic expansion for the distribution function permits analytic evaluation of all the relevant fluid fields. Basic theoretical features of the solution and their astrophysical implications are discussed. As an application, the possibility of describing the dynamics of slowly time-varying accretion flows and the self-generation of magnetic field by means of a ''kinetic dynamo effect'' are discussed. Both effects are shown to be related to intrinsically kinetic physical mechanisms.

  3. Plasma stream transport method (2) Use of charge exchange plasma source

    International Nuclear Information System (INIS)

    Tsuchimoto, T.

    1978-01-01

    The plasma stream transport method using a single plasma source has limitations for practical film deposition. Using a charge exchange phenomenon, a new plasma source is devised and tested by the plasma stream transport machine. Metals, silicon dioxide, and nitride films are deposited by this system. The mechanism of deposition under relatively high vacuum surrounding a silicon wafer is discussed as is the effect of radical atoms

  4. Magnetic Cusp and Electric Nested- or Single-Well Configurations for High Density Antihydrogen and Fusion Nonneutral Plasma Applications

    International Nuclear Information System (INIS)

    C.A. Ordonez

    1999-01-01

    Malmberg-Penning traps have had limited uses for applications that require high density nonneutral plasma confinement. For such traps, the density is severely limited because a magnetic field is used to provide a radially inward force to balance both self-electric and centrifugal radially outward forces. A possible way to confine higher density nonneutral plasmas is to use a magnetic cusp configuration. An annular nonneutral plasma would be confined in the radial magnetic field of a magnetic cusp such that radial confinement is provided by an externally produced electric potential well while axial confinement is provided by the magnetic field. In addition, a radial electric potential profile having a nested-well configuration can be used to simultaneously confine two oppositely signed plasma species (e.g., positrons and antiprotons) that overlap. In the work reported, various aspects of using magnetic cusp configurations and electric nested-well configurations are considered. Plasma confinement with these configurations may be useful for obtaining fast antihydrogen recombination and trapping rates and for achieving practical fusion power production

  5. Magnetic cusp and electric nested- or single-well configurations for high density antihydrogen and fusion nonneutral plasma applications

    International Nuclear Information System (INIS)

    Ordonez, C. A.

    1999-01-01

    Malmberg-Penning traps have had limited uses for applications that require high density nonneutral plasma confinement. For such traps, the density is severely limited because a magnetic field is used to provide a radially inward force to balance both self-electric and centrifugal radially outward forces. A possible way to confine higher density nonneutral plasmas is to use a magnetic cusp configuration. An annular nonneutral plasma would be confined in the radial magnetic field of a magnetic cusp such that radial confinement is provided by an externally produced electric potential well while axial confinement is provided by the magnetic field. In addition, a radial electric potential profile having a nested-well configuration can be used to simultaneously confine two oppositely signed plasma species (e.g., positrons and antiprotons) that overlap. In the work reported, various aspects of using magnetic cusp configurations and electric nested-well configurations are considered. Plasma confinement with these configurations may be useful for obtaining fast antihydrogen recombination and trapping rates and for achieving practical fusion power production

  6. Plasma-surface interaction in negative hydrogen ion sources

    Science.gov (United States)

    Wada, Motoi

    2018-05-01

    A negative hydrogen ion source delivers more beam current when Cs is introduced to the discharge, but a continuous operation of the source reduces the beam current until more Cs is added to the source. This behavior can be explained by adsorption and ion induced desorption of Cs atoms on the plasma grid surface of the ion source. The interaction between the ion source plasma and the plasma grid surface of a negative hydrogen ion source is discussed in correlation to the Cs consumption of the ion source. The results show that operation with deuterium instead of hydrogen should require more Cs consumption and the presence of medium mass impurities as well as ions of the source wall materials in the arc discharge enlarges the Cs removal rate during an ion source discharge.

  7. Capillary plasma jet: A low volume plasma source for life science applications

    Energy Technology Data Exchange (ETDEWEB)

    Topala, I., E-mail: ionut.topala@uaic.ro, E-mail: tmnagat@ipc.shizuoka.ac.jp [Alexandru Ioan Cuza University of Iasi, Faculty of Physics, Iasi Plasma Advanced Research Center (IPARC), Bd. Carol I No. 11, Iasi 700506 (Romania); Nagatsu, M., E-mail: ionut.topala@uaic.ro, E-mail: tmnagat@ipc.shizuoka.ac.jp [Graduate School of Science and Technology, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu 432-8561 (Japan)

    2015-02-02

    In this letter, we present results from multispectroscopic analysis of protein films, after exposure to a peculiar plasma source, i.e., the capillary plasma jet. This plasma source is able to generate very small pulsed plasma volumes, in kilohertz range, with characteristic dimensions smaller than 1 mm. This leads to specific microscale generation and transport of all plasma species. Plasma diagnosis was realized using general electrical and optical methods. Depending on power level and exposure duration, this miniature plasma jet can induce controllable modifications to soft matter targets. Detailed discussions on protein film oxidation and chemical etching are supported by results from absorption, X-ray photoelectron spectroscopy, and microscopy techniques. Further exploitation of principles presented here may consolidate research interests involving plasmas in biotechnologies and plasma medicine, especially in patterning technologies, modified biomolecule arrays, and local chemical functionalization.

  8. Capillary plasma jet: A low volume plasma source for life science applications

    Science.gov (United States)

    Topala, I.; Nagatsu, M.

    2015-02-01

    In this letter, we present results from multispectroscopic analysis of protein films, after exposure to a peculiar plasma source, i.e., the capillary plasma jet. This plasma source is able to generate very small pulsed plasma volumes, in kilohertz range, with characteristic dimensions smaller than 1 mm. This leads to specific microscale generation and transport of all plasma species. Plasma diagnosis was realized using general electrical and optical methods. Depending on power level and exposure duration, this miniature plasma jet can induce controllable modifications to soft matter targets. Detailed discussions on protein film oxidation and chemical etching are supported by results from absorption, X-ray photoelectron spectroscopy, and microscopy techniques. Further exploitation of principles presented here may consolidate research interests involving plasmas in biotechnologies and plasma medicine, especially in patterning technologies, modified biomolecule arrays, and local chemical functionalization.

  9. Computers in plasma physics: remote data access and magnetic configuration design

    International Nuclear Information System (INIS)

    Blackwell, B.D.; McMillan, B.F.; Searle, A.C.; Gardner, H.J.; Price, D.M.; Fredian, T.W.

    2000-01-01

    Full text: Two graphically intensive examples of the application of computers in plasma physics are described remote data access for plasma confinement experiments, and a code for real-time magnetic field tracing and optimisation. The application for both of these is the H-1NF National Plasma Fusion Research Facility, a Commonwealth Major National Research Facility within the Research School of Physical Science, Institute of Advanced Studies, ANU. It is based on the 'flexible' heliac stellarator H-1, a plasma confinement device in which the confining fields are generated solely by external conductors. These complex, fully three dimensional magnetic fields are used as examples for the magnetic design application, and data from plasma physics experiments are used to illustrate the remote access techniques. As plasma fusion experiments grow in size, increased remote access allows physicists to participate in experiments and data analysis from their home base. Three types of access will be described and demonstrated - a simple Java-based web interface, an example TCP client-server built around the widely used MDSPlus data system and the visualisation package IDL (RSI Inc), and a virtual desktop Environment (VNC: AT and T Research) that simulates terminals local to the plasma facility. A client server TCP/IP - web interface to the programmable logic controller that provides user interface to the programmable high power magnet power supplies is described. A very general configuration file allows great flexibility, and allows new displays and interfaces to be created (usually) without changes to the underlying C++ and Java code. The magnetic field code BLINE provides accurate calculation of complex magnetic fields, and 3D visualisation in real time, using a low cost multiprocessor computer and an OpenGL-compatible graphics accelerator. A fast, flexible multi-mesh interpolation method is used for tracing vacuum magnetic field lines created by arbitrary filamentary

  10. Re-configurable ATCA Hardware for Plasma Control and Data Acquisition

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, B.; Batista, A.; Correia, M.; Fernandes, H.; Sousa, J. [Instituto de Plasmas e Fusao Nuclear - Instituto Superior Tecnico, Lisbon (Portugal)

    2009-07-01

    The IST/EURATOM Association is developing a new generation of control and data acquisition hardware for fusion experiments based on the ATCA architecture. This emerging open standard offers a significantly higher data throughput over a reliable High Availability (HA) mechanical and electrical platform. One of this ATCA boards, has 32 galvanic isolated ADC channels (18 bit) each mounted on a exchangeable plug-in card, 8 DAC channels (16 bit), 8 digital I/O channels and embeds a high performance XILINX Virtex 4 family field programmable gate array (FPGA). The specific modular hardware design enables adaptable utilization of the board in dissimilar applications. The first configuration, specially developed for tokamak plasma Vertical Stabilization, consists of a Multiple-Input-Multiple-Output (MIMO) controller that is capable of feedback loops faster than 1 ms, using a multitude of input signals fed from different boards communicating through the Aurora point-to-point protocol. Massive parallel algorithms can be implemented inside the FPGA either with programmed digital logic, using a HDL hardware description language, or inside the two included silicon PowerPCs running a full fledged real-time operating system. The second board configuration is dedicated for transient recording of the entire 32 channels at 2 MSamples/s to the built-in 512 MBDDR2 memory. Signal data retrieval is accelerated by a DMA-driven PCI Express-x1 Interface to the ATCA system controller providing an overall throughput in excess of 250 MB/s. This paper illustrates these developments and discusses possible configurations for foreseen applications. (authors)

  11. Numerical simulation on multi-peak magnetic field configuration for negative hydrogen ion source

    International Nuclear Information System (INIS)

    Wang Xiaomin; Yang Chao; Liu Dagang; Wang Xueqiong

    2011-01-01

    Based on the magnetic charge model, the numerical algorithm of three-dimensional permanent magnets was derived by the finite difference method. Then combining the full three-dimensional particle-in-cell/Monte Carlo algorithm (PIC/MCC), two multi-peak magnetic field configurations, external magnetic filter and tent-shaped filter, were analyzed respectively, and their influences on electron energy distribution were compared. The simulation results show that both configurations can confine the diffusion of particles and can extract negative hydrogen ions; their electron energy distributions are basically similar, presenting double energy state, which are consistent with the basic mechanism of plasma discharge. The former configuration is stronger in confining and can produce more particles, whose total number is approximately four times that of the latter. The tent-shaped magnetic filter can efficiently prevent electron drift caused by inhomogeneous longitudinal magnetic field, leading to more uniform spatial distribution of negative hydrogen ions. The results of simulation are consistent with those from the foreign experiment. (authors)

  12. Influence of ion source configuration and its operation parameters on the target sputtering and implantation process.

    Science.gov (United States)

    Shalnov, K V; Kukhta, V R; Uemura, K; Ito, Y

    2012-06-01

    In the work, investigation of the features and operation regimes of sputter enhanced ion-plasma source are presented. The source is based on the target sputtering with the dense plasma formed in the crossed electric and magnetic fields. It allows operation with noble or reactive gases at low pressure discharge regimes, and, the resulting ion beam is the mixture of ions from the working gas and sputtering target. Any conductive material, such as metals, alloys, or compounds, can be used as the sputtering target. Effectiveness of target sputtering process with the plasma was investigated dependently on the gun geometry, plasma parameters, and the target bias voltage. With the applied accelerating voltage from 0 to 20 kV, the source can be operated in regimes of thin film deposition, ion-beam mixing, and ion implantation. Multi-component ion beam implantation was applied to α-Fe, which leads to the surface hardness increasing from 2 GPa in the initial condition up to 3.5 GPa in case of combined N(2)-C implantation. Projected range of the implanted elements is up to 20 nm with the implantation energy 20 keV that was obtained with XPS depth profiling.

  13. Directional sound beam emission from a configurable compact multi-source system

    KAUST Repository

    Zhao, Jiajun

    2018-01-12

    We propose to achieve efficient emission of highly directional sound beams from multiple monopole sources embedded in a subwavelength enclosure. Without the enclosure, the emitted sound fields have an indistinguishable or omnidirectional radiation directivity in far fields. The strong directivity formed in the presence of the enclosure is attributed to interference of sources under degenerate Mie resonances in the enclosure of anisotropic property. Our numerical simulations of sound emission from the sources demonstrate the radiation of a highly directed sound beam of unidirectional or bidirectional patterns, depending on how the sources are configured inside the enclosure. Our scheme, if achieved, can solve the challenging problem of poor directivity of a subwavelength sound system, and can guide beam forming and collimation by miniaturized devices.

  14. Confinement characteristics of the TPE reversed field pinch plasmas and effects of the boundary configuration

    International Nuclear Information System (INIS)

    Yagi, Y.; Maejima, Y.; Zollino, G.

    2001-01-01

    Confinement characteristics of the TPE series reversed field pinch (RFP) machines, TPE-1RM15, TPE-1RM20 and TPE-1RM20mod, at Electrotechnical Laboratory (ETL) are summarized. Especially data are synthesized in respect to the effects of the different boundary structures of the machines, where shell proximity and overlapped poloidal shell gaps by the multi-layered shell structure are featured. Comparison of the experimental results is shown in terms of the characteristics of magnetic fluctuations, global confinement properties in general, operation capability of the improved confinement in high pinch parameter (Q) discharges and locked mode events. Linear growth rate of the unstable modes as a function of the shell distance is numerically simulated. Understandings of RFP plasma physics have also made progress by the most recent intensive experiments on correlation studies between fast electrons and dynamo activities and measurement of the plasma and mode rotation. TPE-1RM20mod was shutdown in December 1996 and new RFP experiment has started in TPE-RX from March 1998. The new machine also succeeds the concept of the shell configuration of the TPE-1RM20. (author)

  15. The influence of plasma flows bringing the magnetotail back to a more symmetric configuration

    Science.gov (United States)

    Reistad, J. P.; Østgaard, N.; Laundal, K.; Tenfjord, P.; Snekvik, K.; Haaland, S.; Milan, S. E.; Ohma, A.; Grocott, A.; Oksavik, K.

    2017-12-01

    Research from the past decades, most importantly conjugate studies, have shown extensive evidence of the Earth's closed magnetotail being highly displaced from the quiet-day configuration in response to the IMF interacting with the magnetosphere. By displaced we here refer to the mapping of magnetic field-lines from one hemisphere to the other. The large-scale ionospheric convection related to such displaced closed field-lines has also been studied, showing that the footprint in one hemisphere tend to move faster to reduce the displacement, a process we refer to as the restoring of symmetry. Although the appearance and occurrence of the plasma flows related to the restoring of symmetry has been shown to have a strong Interplanetary Magnetic Field (IMF) control, its dynamics and relation to internal magnetospheric processes are unknown. Using multiple years of line-of-sight measurements of the ionospheric plasma convection from the Super Dual Auroral Radar Network binned by IMF, season, and SML index, we have found that the restoring symmetry flows dominate the average convection pattern in the nightside ionosphere during low levels of magnetotail activity, quantified by the SML index. For increasing magnetotail activity, signatures of the restoring symmetry process become less and less pronounced in the global average convection maps. This effect is seen for all clock angles away from IMF By = 0. These results are relevant in order to better understand the dynamic evolution of flux-tubes in the asymmetric magnetosphere.

  16. Shunting arc plasma source for pure carbon ion beam

    Energy Technology Data Exchange (ETDEWEB)

    Koguchi, H.; Sakakita, H.; Kiyama, S.; Shimada, T.; Sato, Y.; Hirano, Y. [Energy Technology Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan)

    2012-02-15

    A plasma source is developed using a coaxial shunting arc plasma gun to extract a pure carbon ion beam. The pure carbon ion beam is a new type of deposition system for diamond and other carbon materials. Our plasma device generates pure carbon plasma from solid-state carbon material without using a hydrocarbon gas such as methane gas, and the plasma does not contain any hydrogen. The ion saturation current of the discharge measured by a double probe is about 0.2 mA/mm{sup 2} at the peak of the pulse.

  17. Shunting arc plasma source for pure carbon ion beam.

    Science.gov (United States)

    Koguchi, H; Sakakita, H; Kiyama, S; Shimada, T; Sato, Y; Hirano, Y

    2012-02-01

    A plasma source is developed using a coaxial shunting arc plasma gun to extract a pure carbon ion beam. The pure carbon ion beam is a new type of deposition system for diamond and other carbon materials. Our plasma device generates pure carbon plasma from solid-state carbon material without using a hydrocarbon gas such as methane gas, and the plasma does not contain any hydrogen. The ion saturation current of the discharge measured by a double probe is about 0.2 mA∕mm(2) at the peak of the pulse.

  18. Plasma control for efficient extreme ultra-violet source

    International Nuclear Information System (INIS)

    Takahashi, Kensaku; Nakajima, Mitsuo; Kawamura, Tohru; Shiho, Makoto; Hotta, Eiki; Horioka, Kazuhiko

    2008-01-01

    To generate a high efficiency extreme-ultraviolet (EUV) source, effects of plasma shape for controlling radiative plasmas based on xenon capillary discharge are experimentally investigated. The radiation characteristics observed via tapered capillary discharge are compared with those of straight one. From the comparison, the long emission period and different plasma behaviors of tapered capillary discharge are confirmed. This means that control of the plasma geometry is effective for prolonging the EUV emission period. This result also indicates that the plasma shape control seems to have a potential for enhancing the conversion efficiency. (author)

  19. Ferroelectric plasma source for heavy ion beam space charge neutralization

    International Nuclear Information System (INIS)

    Efthimion, Philip C.; Gilson, Erik P.; Davidson, Ronald C.; Grisham, Larry; Grant Logan, B.; Seidl, Peter A.; Waldron, William; Yu, Simon S.

    2007-01-01

    Plasmas are a source of unbound electrons for charge neutralizing intense heavy ion beams to allow them to focus to a small spot size and compress their axial pulse length. The plasma source should be able to operate at low neutral pressures and without strong externally applied electric or magnetic fields. To produce 1 m-long plasma columns, sources based upon ferroelectric ceramics with large dielectric coefficients are being developed. The sources utilize the ferroelectric ceramic BaTiO 3 to form metal plasma. The drift tube inner surface of the Neutralized Drift Compression Experiment (NDCX) will be covered with ceramic material, and high voltage (∼7 kV) will be applied between the drift tube and the front surface of the ceramics. A prototype ferroelectric source, 20 cm in length, has produced plasma densities of 5x10 11 cm -3 . It was integrated into the Neutralized Transport Experiment (NTX), and successfully charge neutralized the K + ion beam. A 1 m-long source comprised of five 20-cm-long sources has been tested. Simply connecting the five sources in parallel to a single pulse forming network power supply yielded non-uniform performance due to the time-dependent nature of the load that each of the five plasma sources experiences. Other circuit combinations have been considered, including powering each source by its own supply. The 1-m-long source has now been successfully characterized, producing relatively uniform plasma over the 1 m length of the source in the mid-10 10 cm -3 density range. This source will be integrated into the NDCX device for charge neutralization and beam compression experiments

  20. Influence of the configuration of the magnetic filter field on the discharge structure in the RF driven negative ion source prototype for fusion

    Science.gov (United States)

    Lishev, S.; Schiesko, L.; Wünderlich, D.; Fantz, U.

    2017-08-01

    The study provides results for the influence of the filter field topology on the plasma parameters in the RF prototype negative ion source for ITER NBI. A previously developed 2D fluid plasma model of the prototype source was extended towards accounting for the particles and energy losses along the magnetic field lines and the presence of a magnetic field in the driver which is the case at the BATMAN and ELISE test-beds. The effect of the magnetic field in the driver is shown for the magnetic field configuration of the prototype source (i.e. a magnetic field produced by an external magnet frame) by comparison of plasma parameters without and with the magnetic field in the driver and for different axial positions of the filter. Since the ELISE-like magnetic field (i.e. a magnetic field produced by a current flowing through the plasma grid) is a new feature planned to be installed at the BATMAN test-bed, its effect on the discharge structure was studied for different strengths of the magnetic field. The obtained results show for both configurations of the magnetic filter the same main features in the patterns of the plasma parameters in the expansion chamber: a strong axial drop of the electron temperature and the formation of a groove accompanied with accumulation of electrons in front of the plasma grid. The presence of a magnetic field in the driver has a local impact on the plasma parameters: the formation of a second groove of the electron temperature in the case of BATMAN (due to the reversed direction of the filter field in the driver) and a strong asymmetry of the electron density. Accounting for the additional losses in the third dimension suppresses the drifts across the magnetic field and, thus, the variations of the electron density in the expansion chamber are less pronounced.

  1. The requirements for low-temperature plasma ionization support miniaturization of the ion source.

    Science.gov (United States)

    Kiontke, Andreas; Holzer, Frank; Belder, Detlev; Birkemeyer, Claudia

    2018-06-01

    Ambient ionization mass spectrometry (AI-MS), the ionization of samples under ambient conditions, enables fast and simple analysis of samples without or with little sample preparation. Due to their simple construction and low resource consumption, plasma-based ionization methods in particular are considered ideal for use in mobile analytical devices. However, systematic investigations that have attempted to identify the optimal configuration of a plasma source to achieve the sensitive detection of target molecules are still rare. We therefore used a low-temperature plasma ionization (LTPI) source based on dielectric barrier discharge with helium employed as the process gas to identify the factors that most strongly influence the signal intensity in the mass spectrometry of species formed by plasma ionization. In this study, we investigated several construction-related parameters of the plasma source and found that a low wall thickness of the dielectric, a small outlet spacing, and a short distance between the plasma source and the MS inlet are needed to achieve optimal signal intensity with a process-gas flow rate of as little as 10 mL/min. In conclusion, this type of ion source is especially well suited for downscaling, which is usually required in mobile devices. Our results provide valuable insights into the LTPI mechanism; they reveal the potential to further improve its implementation and standardization for mobile mass spectrometry as well as our understanding of the requirements and selectivity of this technique. Graphical abstract Optimized parameters of a dielectric barrier discharge plasma for ionization in mass spectrometry. The electrode size, shape, and arrangement, the thickness of the dielectric, and distances between the plasma source, sample, and MS inlet are marked in red. The process gas (helium) flow is shown in black.

  2. Electron heat transport analysis of low-collisionality plasmas in the neoclassical-transport-optimized configuration of LHD

    International Nuclear Information System (INIS)

    Murakami, Sadayoshi; Yamada, Hiroshi; Wakasa, Arimitsu

    2002-01-01

    Electron heat transport in low-collisionality LHD plasma is investigated in order to study the neoclassical transport optimization effect on thermal plasma transport with an optimization level typical of so-called ''advanced stellarators''. In the central region, a higher electron temperature is obtained in the optimized configuration, and transport analysis suggests the considerable effect of neoclassical transport on the electron heat transport assuming the ion-root level of radial electric field. The obtained experimental results support future reactor design in which the neoclassical and/or anomalous transports are reduced by magnetic field optimization in a non-axisymmetric configuration. (author)

  3. RF plasma source for heavy ion beam charge neutralization

    International Nuclear Information System (INIS)

    Efthimion, Philip C.; Gilson, Erik; Grisham, Larry; Davidson, Ronald C.; Yu, Simon S.; Logan, B. Grant

    2003-01-01

    Highly ionized plasmas are being used as a medium for charge neutralizing heavy ion beams in order to focus the ion beam to a small spot size. A radio frequency (RF) plasma source has been built at the Princeton Plasma Physics Laboratory (PPPL) in support of the joint Neutralized Transport Experiment (NTX) at the Lawrence Berkeley National Laboratory (LBNL) to study ion beam neutralization with plasma. The goal is to operate the source at pressures ∼ 10 -5 Torr at full ionization. The initial operation of the source has been at pressures of 10 -4 -10 -1 Torr and electron densities in the range of 10 8 -10 11 cm -3 . Recently, pulsed operation of the source has enabled operation at pressures in the 10 -6 Torr range with densities of 10 11 cm -3 . Near 100% ionization has been achieved. The source has been integrated with the NTX facility and experiments have begun

  4. Two-chamber configuration of Bio-Nano electron cyclotron resonance ion source for fullerene modification

    Energy Technology Data Exchange (ETDEWEB)

    Uchida, T., E-mail: uchida-t@toyo.jp [Bio-Nano Electronics Research Centre, Toyo University, Kawagoe 350-8585 (Japan); Graduate School of Interdisciplinary New Science, Toyo University, Kawagoe 350-8585 (Japan); Rácz, R.; Biri, S. [Institute for Nuclear Research (Atomki), Hungarian Academy of Sciences, Bem tér 18/C, H-4026 Debrecen (Hungary); Muramatsu, M.; Kitagawa, A. [National Institute of Radiological Sciences (NIRS), Chiba 263-8555 (Japan); Kato, Y. [Graduate School of Engineering, Osaka University, Suita 565-0871 (Japan); Yoshida, Y. [Bio-Nano Electronics Research Centre, Toyo University, Kawagoe 350-8585 (Japan); Faculty of Science and Engineering, Toyo University, Kawagoe 350-8585 (Japan)

    2016-02-15

    We report on the modification of fullerenes with iron and chlorine using two individually controllable plasmas in the Bio-Nano electron cyclotron resonance ion source (ECRIS). One of the plasmas is composed of fullerene and the other one is composed of iron and chlorine. The online ion beam analysis allows one to investigate the rate of the vapor-phase collisional modification process in the ECRIS, while the offline analyses (e.g., liquid chromatography-mass spectrometry) of the materials deposited on the plasma chamber can give information on the surface-type process. Both analytical methods show the presence of modified fullerenes such as fullerene-chlorine, fullerene-iron, and fullerene-chlorine-iron.

  5. Ferroelectric Plasma Source for Heavy Ion Beam Charge Neutralization

    CERN Document Server

    Efthimion, Philip; Gilson, Erik P; Grisham, Larry; Logan, B G; Waldron, William; Yu, Simon

    2005-01-01

    Plasmas are employed as a medium for charge neutralizing heavy ion beams to allow them to focus to a small spot size. Calculations suggest that plasma at a density of 1-100 times the ion beam density and at a length ~ 0.1-1 m would be suitable. To produce 1 meter plasma, large-volume plasma sources based upon ferroelectric ceramics are being considered. These sources have the advantage of being able to increase the length of the plasma and operate at low neutral pressures. The source will utilize the ferroelectric ceramic BaTiO3 to form metal plasma. The drift tube inner surface of the Neutralized Drift Compression Experiment (NDCX) will be covered with ceramic. High voltage (~ 1-5 kV) is applied between the drift tube and the front surface of the ceramic by placing a wire grid on the front surface. A prototype ferroelectric source 20 cm long produced plasma densities ~ 5x1011 cm-3. The source was integrated into the experiment and successfully charge neutralized the K ion beam. Presently, the 1 meter source ...

  6. Modeling of low pressure plasma sources for microelectronics fabrication

    International Nuclear Information System (INIS)

    Agarwal, Ankur; Bera, Kallol; Kenney, Jason; Rauf, Shahid; Likhanskii, Alexandre

    2017-01-01

    Chemically reactive plasmas operating in the 1 mTorr–10 Torr pressure range are widely used for thin film processing in the semiconductor industry. Plasma modeling has come to play an important role in the design of these plasma processing systems. A number of 3-dimensional (3D) fluid and hybrid plasma modeling examples are used to illustrate the role of computational investigations in design of plasma processing hardware for applications such as ion implantation, deposition, and etching. A model for a rectangular inductively coupled plasma (ICP) source is described, which is employed as an ion source for ion implantation. It is shown that gas pressure strongly influences ion flux uniformity, which is determined by the balance between the location of plasma production and diffusion. The effect of chamber dimensions on plasma uniformity in a rectangular capacitively coupled plasma (CCP) is examined using an electromagnetic plasma model. Due to high pressure and small gap in this system, plasma uniformity is found to be primarily determined by the electric field profile in the sheath/pre-sheath region. A 3D model is utilized to investigate the confinement properties of a mesh in a cylindrical CCP. Results highlight the role of hole topology and size on the formation of localized hot-spots. A 3D electromagnetic plasma model for a cylindrical ICP is used to study inductive versus capacitive power coupling and how placement of ground return wires influences it. Finally, a 3D hybrid plasma model for an electron beam generated magnetized plasma is used to understand the role of reactor geometry on plasma uniformity in the presence of E  ×  B drift. (paper)

  7. Modeling of low pressure plasma sources for microelectronics fabrication

    Science.gov (United States)

    Agarwal, Ankur; Bera, Kallol; Kenney, Jason; Likhanskii, Alexandre; Rauf, Shahid

    2017-10-01

    Chemically reactive plasmas operating in the 1 mTorr-10 Torr pressure range are widely used for thin film processing in the semiconductor industry. Plasma modeling has come to play an important role in the design of these plasma processing systems. A number of 3-dimensional (3D) fluid and hybrid plasma modeling examples are used to illustrate the role of computational investigations in design of plasma processing hardware for applications such as ion implantation, deposition, and etching. A model for a rectangular inductively coupled plasma (ICP) source is described, which is employed as an ion source for ion implantation. It is shown that gas pressure strongly influences ion flux uniformity, which is determined by the balance between the location of plasma production and diffusion. The effect of chamber dimensions on plasma uniformity in a rectangular capacitively coupled plasma (CCP) is examined using an electromagnetic plasma model. Due to high pressure and small gap in this system, plasma uniformity is found to be primarily determined by the electric field profile in the sheath/pre-sheath region. A 3D model is utilized to investigate the confinement properties of a mesh in a cylindrical CCP. Results highlight the role of hole topology and size on the formation of localized hot-spots. A 3D electromagnetic plasma model for a cylindrical ICP is used to study inductive versus capacitive power coupling and how placement of ground return wires influences it. Finally, a 3D hybrid plasma model for an electron beam generated magnetized plasma is used to understand the role of reactor geometry on plasma uniformity in the presence of E  ×  B drift.

  8. Plasma focus as a pulsed power source

    International Nuclear Information System (INIS)

    Sahlin, H.; McFarland, G.; Barlett, R.; Gullickson, R.

    1975-01-01

    The plasma focus is a remarkable natural phenomena that achieves significant space-time compression of both particle and field energy. Depending on the mode of operation, about 20 percent of the bank energy can be concentrated into the kinetic energy of a thin, dense, cylindrically convergent gas shell, or into a small-diameter, high-ν/γ relativistic electron burst and oppositely directed ion burst. The kinetic energy of the fast ions and electrons can exceed the applied voltage by a factor of greater than 100. The different modes of energy concentration by the plasma focus are presented and discussed both in terms of their role in the direct yield of the focus and for the case of a plasma focus supplemented by various fusionable targets

  9. Spectroscopic measurements of anode plasma with cryogenic pulsed ion sources

    International Nuclear Information System (INIS)

    Yoneda, H.; Urata, T.; Ohbayashi, K.; Kim, Y.; Horioka, K.; Kasuya, K.

    1987-01-01

    In ion beam diodes, electromagnetic wave is coupled to ion beam. Ion is extracted from anode plasma, which is produced early in the power pulse. However, exact mechanism of anode plasma production, expansion and ion extraction process is unknown. In particularly, anode plasma expansion is seemed to be one of the reasons of rapid impedance collapse of the diode, which is serious problem in high power experiments. Some experimental results showed that anode plasma expansion velocity was about 5 times larger than that inferred from simple thermal velocity. Several explanations for these results were proposed; for example, electron collisionarity in anode plasma, fast neutral gas particle, diamagnetism. To solve this question, it is necessary to measure the characteristic of anode plasma with space and time resolution. The authors made spectroscopic measurements to investigate variety of electron temperature, electron density, expansion velocity of anode plasma with various ion sources

  10. Modeling, numerical simulation and optimal control of plasma configuration evolution for the NET Tokamak and for the future generation of nuclear fusion

    International Nuclear Information System (INIS)

    Bourbon, F.

    1993-03-01

    The present thesis treats of the modeling, of the numerical simulation and equilibrium optimal control and configuration evolution of the plasma in a tokamak. In the first chapter, we establish the problem of equilibrium of the plasma by the finite elements method and a Newton algorithm. Then, we investigate the problem of equilibrium control: determination of currents in circuits of the tokamak to reach a given configuration. In the third chapter, we develop a model for evolution of the plasma configuration during a discharge. We solve this question by a Newton algorithm; with the fourth chapter, we treat the monitoring of plasma configuration evolution

  11. Numerical study of plasma generation process and internal antenna heat loadings in J-PARC RF negative ion source

    Energy Technology Data Exchange (ETDEWEB)

    Shibata, T., E-mail: shibat@post.j-parc.jp; Ueno, A.; Oguri, H.; Ohkoshi, K.; Ikegami, K.; Takagi, A.; Asano, H.; Naito, F. [J-PARC Center, Tokai-mura, Naka-gun, Ibaraki-ken 319-1195 (Japan); Nishida, K.; Mochizuki, S.; Hatayama, A. [Keio University, Hiyoshi, Kohoku-ku, Yokohama-shi, Kanagawa-ken 223-8522 (Japan); Mattei, S.; Lettry, J. [European Organization for Nuclear Research (CERN), 1211 Geneva 23 (Switzerland)

    2016-02-15

    A numerical model of plasma transport and electromagnetic field in the J-PARC (Japan Proton Accelerator Research Complex) radio frequency ion source has been developed to understand the relation between antenna coil heat loadings and plasma production/transport processes. From the calculation, the local plasma density increase is observed in the region close to the antenna coil. Electrons are magnetized by the magnetic field line with absolute magnetic flux density 30–120 Gauss which leads to high local ionization rate. The results suggest that modification of magnetic configuration can be made to reduce plasma heat flux onto the antenna.

  12. Studies of electron cyclotron resonance ion source plasma physics

    International Nuclear Information System (INIS)

    Tarvainen, O.

    2005-01-01

    This thesis consists of an introduction to the plasma physics of electron cyclotron resonance ion sources (ECRIS) and a review of the results obtained by the author and co-workers including discussion of related work by others. The thesis begins with a theoretical discussion dealing with plasma physics relevant for the production of highly charged ions in ECR ion source plasmas. This is followed by an overview of different techniques, such as gas mixing and double frequency heating, that can be used to improve the performance of this type of ion source. The experimental part of the work consists of studies related to ECRIS plasma physics. The effect of the gas mixing technique on the production efficiency of different ion beams was studied with both gaseous and solid materials. It was observed that gas mixing improves the confinement of the heavier element while the confinement of the lighter element is reduced. When the effect of gas mixing on MIVOC-plasmas was studied with several mixing gases it was observed that applying this technique can reduce the inevitable carbon contamination by a significant factor. In order to understand the different plasma processes taking place in ECRIS plasmas, a series of plasma potential and emittance measurements was carried out. An instrument, which can be used to measure the plasma potential in a single measurement without disturbing the plasma, was developed for this work. Studying the plasma potential of ECR ion sources is important not only because it helps to understand different plasma processes, but also because the information can be used as an input parameter for beam transport simulations and ion source extraction design. The experiments performed have revealed clear dependencies of the plasma potential on certain source parameters such as the amount of carbon contamination accumulated on the walls of the plasma chamber during a MIVOC-run. It was also observed that gas mixing affects not only the production efficiency

  13. Long plasma source for heavy ion beam charge neutralization

    International Nuclear Information System (INIS)

    Efthimion, Philip C.; Gilson, Erik P.; Grisham, Larry; Davidson, Ronald C.; Grant Logan, Larry B.; Seidl, Peter A.; Waldron, William

    2009-01-01

    Plasmas are a source of unbound electrons for charge neutralizing intense heavy ion beams to focus them to a small spot size and compress their axial length. The plasma source should operate at low neutral pressures and without strong externally applied fields. To produce long plasma columns, sources based upon ferroelectric ceramics with large dielectric coefficients have been developed. The source utilizes the ferroelectric ceramic BaTiO 3 to form metal plasma. The drift tube inner surface of the Neutralized Drift Compression Experiment (NDCX) is covered with ceramic material. High voltage (∼8 kV) is applied between the drift tube and the front surface of the ceramics. A BaTiO 3 source comprised of five 20-cm-long sources has been tested and characterized, producing relatively uniform plasma in the 5x10 10 cm -3 density range. The source was integrated into the NDCX device for charge neutralization and beam compression experiments, and yielded current compression ratios ∼120. Present research is developing multi-meter-long and higher density sources to support beam compression experiments for high-energy-density physics applications.

  14. Optimal configuration of power grid sources based on optimal particle swarm algorithm

    Science.gov (United States)

    Wen, Yuanhua

    2018-04-01

    In order to optimize the distribution problem of power grid sources, an optimized particle swarm optimization algorithm is proposed. First, the concept of multi-objective optimization and the Pareto solution set are enumerated. Then, the performance of the classical genetic algorithm, the classical particle swarm optimization algorithm and the improved particle swarm optimization algorithm are analyzed. The three algorithms are simulated respectively. Compared with the test results of each algorithm, the superiority of the algorithm in convergence and optimization performance is proved, which lays the foundation for subsequent micro-grid power optimization configuration solution.

  15. Electron Beam Diagnosis and Dynamics using DIADYN Plasma Source

    International Nuclear Information System (INIS)

    Toader, D.; Craciun, G.; Manaila, E.; Oproiu, C.; Marghitu, S.

    2009-01-01

    This paper is presenting results obtained with the DIADYN installation after replacing its vacuum electron source (VES L V) with a plasma electron source (PES L V). DIADYN is a low energy laboratory equipment operating with 10 to 50 keV electron beams and designed to help realize non-destructive diagnosis and dynamics for low energy electron beams but also to be used in future material irradiations. The results presented here regard the beam diagnosis and dynamics made with beams obtained from the newly replaced plasma source. We discuss both results obtained in experimental dynamics and dynamics calculation results for electron beams extracted from the SEP L V source.

  16. Negative ion surface plasma source development for plasma trap injectors in Novosibirsk

    International Nuclear Information System (INIS)

    Bel'chenko, Yu.I.; Dimov, G.I.; Dudnikov, V.G.; Kupriyanov, A.S.

    1989-01-01

    Work on high-current ion sources carried out at the Novosibirsk Institute of Nuclear Physics (INP) is presented. The INP investigations on ''pure plasma'' planotron and ''pure surface'' secondary emission systems of H - generation, which preceded the surface-plasma concept developed in Novosibirsk, are described. The physical basis of the surface-plasma method of negative-ion production is considered. The versions and operating characteristics of different surface-plasma sources including the multi-ampere (approx-gt 10A) source are discussed. Research on efficient large-area (∼10 2 cm 2 ) negative ion surface-plasma emitters is described. The INP long-pulse multiaperture surface- plasma generators, with a current of about 1A, are described. 38 refs., 17 figs

  17. Characterization of an electrothermal plasma source for fusion transient simulations

    Science.gov (United States)

    Gebhart, T. E.; Baylor, L. R.; Rapp, J.; Winfrey, A. L.

    2018-01-01

    The realization of fusion energy requires materials that can withstand high heat and particle fluxes at the plasma material interface. In this work, an electrothermal (ET) plasma source has been designed as a transient heat flux source for a linear plasma material interaction device. An ET plasma source operates in the ablative arc regime driven by a DC capacitive discharge. The current channel width is defined by the 4 mm bore of a boron nitride liner. At large plasma currents, the arc impacts the liner wall, leading to high particle and heat fluxes to the liner material, which subsequently ablates and ionizes. This results in a high density plasma with a large unidirectional bulk flow out of the source exit. The pulse length for the ET source has been optimized using a pulse forming network to have durations of 1 and 2 ms. The peak currents and maximum source energies seen in this system are 1.9 kA and 1.2 kJ for the 2 ms pulse and 3.2 kA and 2.1 kJ for the 1 ms pulse, respectively. This work is a proof of the principal project to show that an ET source produces electron densities and heat fluxes comparable to those anticipated in transient events in large future magnetic confinement fusion devices. Heat flux, plasma temperature, and plasma density were determined for each shot using infrared imaging and optical spectroscopy techniques. This paper will discuss the assumptions, methods, and results of the experiments.

  18. A Penning-assisted subkilovolt coaxial plasma source

    International Nuclear Information System (INIS)

    Wang Zhehui; Beinke, Paul D.; Barnes, Cris W.; Martin, Michael W.; Mignardot, Edward; Wurden, Glen A.; Hsu, Scott C.; Intrator, Thomas P.; Munson, Carter P.

    2005-01-01

    A Penning-assisted 20 MW coaxial plasma source (plasma gun), which can achieve breakdown at sub-kV voltages, is described. The minimum breakdown voltage is about 400 V, significantly lower than previously reported values of 1-5 kV. The Penning region for electrons is created using a permanent magnet assembly, which is mounted to the inside of the cathode of the coaxial plasma source. A theoretical model for the breakdown is given. A 900 V 0.5 F capacitor bank supplies energy for gas breakdown and plasma sustainment from 4 to 6 ms duration. Typical peak gun current is about 100 kA and gun voltage between anode and cathode after breakdown is about 200 V. A circuit model is used to understand the current-voltage characteristics of the coaxial gun plasma. Energy deposited into the plasma accounts for about 60% of the total capacitor bank energy. This plasma source is uniquely suitable for studying multi-MW multi-ms plasmas with sub-MJ capacitor bank energy

  19. Research on pinches driven by Speed-2 generator: Hard X-ray and neutron emission in plasma focus configuration

    Energy Technology Data Exchange (ETDEWEB)

    Soto, L.; Moreno, J.; Silva, P.; Sylvester, G.; Zambra, M.; Pavez, C. [Comision Chilena de Energia Nuclear, Santiago (Chile); Pavez, C. [Universidad de Concepcion (Chile); Raspa, V. [Buenos Aires Univ., PLADEMA, CONICET and INFIP (Argentina); Castillo, F. [Insitituto de Ciencias Nucleares, UNAM (Mexico); Kies, W. [Heinrich-Heine-Univ., Dusseldorf (Germany)

    2004-07-01

    Speed-2 is a generator based on Marx technology and was designed in the University of Dusseldorf. Speed-2 consists on 40 +/- Marx modules connected in parallel (4.1 {mu}F equivalent Marx generator capacity, 300 kV, 4 MA in short circuit, 187 kJ, 400 ns rise time, dI/dt {approx} 10{sup 13} A/s). Currently Speed-2 is operating at CCHEN (Chilean nuclear energy commission), being the most powerful and energetic device for dense transient plasma in the Southern Hemisphere. Most of the previous works developed in Speed-2 at Dusseldorf were done in a plasma focus configuration for soft X-ray emission and the neutron emission from Speed-2 was not completely studied. The research program at CCHEN considers experiments in different pinch configurations (plasma focus, gas puffed plasma focus, gas embedded Z-pinch, wire arrays) at current of hundred of kilo- to mega-amperes, using the Speed-2 generator. The Chilean operation has begun implementing and developing diagnostics in a conventional plasma focus configuration operating in deuterium in order to characterize the neutron emission and the hard X-ray production. Silver activation counters, plastics CR39 and scintillator-photomultiplier detectors are used to characterize the neutron emission. Images of metallic plates with different thickness are obtained on commercial radiographic film, Agfa Curix ST-G2, in order to characterize an effective energy of the hard X-ray outside of the discharge. (authors)

  20. LLNL large-area inductively coupled plasma (ICP) source: Experiments

    International Nuclear Information System (INIS)

    Richardson, R.A.; Egan, P.O.; Benjamin, R.D.

    1995-05-01

    We describe initial experiments with a large (76-cm diameter) plasma source chamber to explore the problems associated with large-area inductively coupled plasma (ICP) sources to produce high density plasmas useful for processing 400-mm semiconductor wafers. Our experiments typically use a 640-nun diameter planar ICP coil driven at 13.56 MHz. Plasma and system data are taken in Ar and N 2 over the pressure range 3-50 mtorr. RF inductive power was run up to 2000W, but typically data were taken over the range 100-1000W. Diagnostics include optical emission spectroscopy, Langmuir probes, and B probes as well as electrical circuit measurements. The B and E-M measurements are compared with models based on commercial E-M codes. Initial indications are that uniform plasmas suitable for 400-mm processing are attainable

  1. Pulsed, atmospheric pressure plasma source for emission spectrometry

    Science.gov (United States)

    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.

  2. Super Configuration Accounting Equation of State for WDM and HED plasma

    Science.gov (United States)

    Lee, T. G.; Busquet, M.; Gilles, D.; Klapisch, M.

    2017-10-01

    Rad-Hydro numerical codes require Equation of State (EOS) and opacities. We describe a procedure to obtain an EOS compatible with our STA opacity model. We use our relativistic super-configuration code - STA-2.5 to compute the average 〈 Z 〉 and excitation-ionization internal energy U and chemical potential _. These and other data will serve as basic inputs into a Yukawa Monte-Carlo improved version of quotidian EOS, known as YMCQ. The screening in the Yukawa potential describing the ion-ion interaction is modified by the data from STA. This integrated procedure yields the excess internal energy due to the non-ideal behavior of the EOS concordant with our opacity model and allows us to have an EOS model applicable from solid matter to very tenuous plasmas as found in laser fusion, astrophysics, or tokamaks. We shall present its application to Carbon, Aluminum and Iron. This work is made possible by a financial support from DOE/NNSA.

  3. RF Plasma Source for Heavy Ion Beam Charge Neutralization

    Science.gov (United States)

    Efthimion, P. C.; Gilson, E.; Grisham, L.; Davidson, R. C.

    2003-10-01

    Highly ionized plasmas are being employed as a medium for charge neutralizing heavy ion beams in order to focus to a small spot size. Calculations suggest that plasma at a density of 1 - 100 times the ion beam density and at a length 0.1-0.5 m would be suitable for achieving a high level of charge neutralization. An ECR source has been built at the Princeton Plasma Physics Laboratory (PPPL) in support of the joint Neutralized Transport Experiment (NTX) at the Lawrence Berkeley National Laboratory (LBNL) to study ion beam neutralization with plasma. The ECR source operates at 13.6 MHz and with solenoid magnetic fields of 0-10 gauss. The goal is to operate the source at pressures 10-5 Torr at full ionization. The initial operation of the source has been at pressures of 10-4 - 10-1 Torr. Electron densities in the range of 10^8 - 10^11 cm-3 have been achieved. Recently, pulsed operation of the source has enabled operation at pressures in the 10-6 Torr range with densities of 10^11 cm-3. Near 100% ionization has been achieved. The source has been integrated with NTX and is being used in the experiments. The plasma is approximately 10 cm in length in the direction of the beam propagation. Modifications to the source will be presented that increase its length in the direction of beam propagation.

  4. Plasma radiation dynamics with the upgraded Absolute Extreme Ultraviolet tomographical system in the Tokamak à Configuration Variable

    Energy Technology Data Exchange (ETDEWEB)

    Tal, B.; Nagy, D.; Veres, G. [Institute for Particle and Nuclear Physics, Wigner Research Centre for Physics, Hungarian Academy of Sciences, Association EURATOM, P. O. Box 49, H-1525 Budapest (Hungary); Labit, B.; Chavan, R.; Duval, B. [Ecole Polytechnique Fédérale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas, Association EURATOM-Confédération Suisse, EPFL SB CRPP, Station 13, CH-1015 Lausanne (Switzerland)

    2013-12-15

    We introduce an upgraded version of a tomographical system which is built up from Absolute Extreme Ultraviolet-type (AXUV) detectors and has been installed on the Tokamak à Configuration Variable (TCV). The system is suitable for the investigation of fast radiative processes usually observed in magnetically confined high-temperature plasmas. The upgrade consists in the detector protection by movable shutters, some modifications to correct original design errors and the improvement in the data evaluation techniques. The short-term sensitivity degradation of the detectors, which is caused by the plasma radiation itself, has been monitored and found to be severe. The results provided by the system are consistent with the measurements obtained with the usual plasma radiation diagnostics installed on TCV. Additionally, the coupling between core plasma radiation and plasma-wall interaction is revealed. This was impossible with other available diagnostics on TCV.

  5. Development of a long-slot microwave plasma source

    Energy Technology Data Exchange (ETDEWEB)

    Kuwata, Y., E-mail: euo1304@mail4.doshisha.ac.jp; Kasuya, T.; Miyamoto, N.; Wada, M. [Graduate School of Science and Engineering, Doshisha University, Kyotanabe, Kyoto 610-0321 (Japan)

    2016-02-15

    A 20 cm long 10 cm wide microwave plasma source was realized by inserting two 20 cm long 1.5 mm diameter rod antennas into the plasma. Plasma luminous distributions around the antennas were changed by magnetic field arrangement created by permanent magnets attached to the source. The distributions appeared homogeneous in one direction along the antenna when the spacing between the antenna and the source wall was 7.5 mm for the input microwave frequency of 2.45 GHz. Plasma density and temperature at a plane 20 cm downstream from the microwave shield were measured by a Langmuir probe array at 150 W microwave power input. The measured electron density and temperature varied over space from 3.0 × 10{sup 9} cm{sup −3} to 5.8 × 10{sup 9} cm{sup −3}, and from 1.1 eV to 2.1 eV, respectively.

  6. Performance Evaluation of the Single-Phase Split-Source Inverter Using an Alternative DC-AC Configuration

    DEFF Research Database (Denmark)

    Abdelhakim, Ahmed; Mattavelli, Paolo; Davari, Pooya

    2018-01-01

    This paper investigates and evaluates the performance of a single-phase split-source inverter (SSI), where an alternative unidirectional dc-ac configuration is used. Such configuration is utilized in order to use two common-cathode diodes in a single-device instead of using two separate diodes, r...

  7. 77 FR 6463 - Revisions to Labeling Requirements for Blood and Blood Components, Including Source Plasma...

    Science.gov (United States)

    2012-02-08

    ... Blood Components, Including Source Plasma; Correction AGENCY: Food and Drug Administration, HHS. ACTION..., Including Source Plasma,'' which provided incorrect publication information regarding a 60-day notice that...

  8. Verification of source and collimator configuration for Gamma Knife Perfexion using panoramic imaging

    International Nuclear Information System (INIS)

    Cho, Young-Bin; Prooijen, Monique van; Jaffray, David A.; Islam, Mohammad K.

    2010-01-01

    Purpose: The new model of stereotactic radiosurgery system, Gamma Knife Perfexion, allows automatic selection of built-in collimation, eliminating the need for the time consuming manual collimator installation required with previous models. However, the configuration of sources and collimators inside the system does not permit easy access for the verification of the selected collimation. While the conventional method of exposing a film at the isocenter is useful for obtaining composite dose information, it is difficult to interpret the data in terms of the integrity of each individual source and corresponding collimation. The primary aim of this study was to develop a method of verifying the geometric configuration of the sources and collimator modules of the Gamma Knife Perfexion. In addition, the method was extended to make dose measurements and verify the accuracy of dose distributions calculated by the mathematical formalism used in the treatment planning system, Leksell Gamma Plan. Methods: A panoramic view of all of 192 cobalt sources was simultaneously acquired by exposing a radiochromic film wrapped around the surface of a cylindrical phantom. The center of the phantom was mounted at the isocenter with its axis aligned along the longitudinal axis of the couch. The sizes and shapes of the source images projected on the phantom surface were compared to those calculated based on the manufacturer's design specifications. The measured dose at various points on the film was also compared to calculations using the algorithm of the planning system. Results: The panoramic images allowed clear identification of each of the 192 sources, verifying source integrity and selected collimator sizes. Dose on the film surface is due to the primary beam as well as phantom scatter and leakage contributions. Therefore, the dose at a point away from the isocenter cannot be determined simply based on the proportionality of collimator output factors; the use of a dose computation

  9. Hybrid Wing Body Shielding Studies Using an Ultrasonic Configurable Fan Artificial Noise Source Generating Simple Modes

    Science.gov (United States)

    Sutliff, Daniel, L.; Brown, Clifford, A.; Walker, Bruce, E.

    2012-01-01

    An Ultrasonic Configurable Fan Artificial Noise Source (UCFANS) was designed, built, and tested in support of the Langley Research Center s 14- by 22-Foot wind tunnel test of the Hybrid Wing Body (HWB) full three-dimensional 5.8 percent scale model. The UCFANS is a 5.8 percent rapid prototype scale model of a high-bypass turbofan engine that can generate the tonal signature of candidate engines using artificial sources (no flow). The purpose of the test was to provide an estimate of the acoustic shielding benefits possible from mounting the engine on the upper surface of an HWB aircraft and to provide a database for shielding code validation. A range of frequencies, and a parametric study of modes were generated from exhaust and inlet nacelle configurations. Radiated acoustic data were acquired from a traversing linear array of 13 microphones, spanning 36 in. Two planes perpendicular to the axis of the nacelle (in its 0 orientation) and three planes parallel were acquired from the array sweep. In each plane the linear array traversed five sweeps, for a total span of 160 in. acquired. The resolution of the sweep is variable, so that points closer to the model are taken at a higher resolution. Contour plots of Sound Pressure Level, and integrated Power Levels are presented in this paper; as well as the in-duct modal structure.

  10. Plasma Ion Source with an Internal Evaporator

    International Nuclear Information System (INIS)

    Turek, M.; Drozdziel, A.; Pyszniak, K.; Prucnal, S.; Maczka, D.

    2011-01-01

    A new construction of a hollow cathode ion source equipped with an internal evaporator heated by a spiral cathode filament and arc discharge is presented. The source is especially suitable for production of ions from solids. The proximity of arc discharge region and extraction opening enables production of intense ion beams even for very low discharge current (I a = 1.2 A). The currents of 50 μA (Al + ) and 70 μA (Bi + ) were obtained using the extraction voltage of 25 kV. The source is able to work for several tens of hours without maintenance breaks, giving possibility of high dose implantations. The paper presents the detailed description of the ion source as well as its experimental characteristics like dependences of extracted currents and anode voltage on anode and cathode currents. (author)

  11. SCRIC: a code dedicated to the detailed emission and absorption of heterogeneous NLTE plasmas; application to xenon EUV sources

    International Nuclear Information System (INIS)

    Gaufridy de Dortan, F. de

    2006-01-01

    Nearly all spectral opacity codes for LTE and NLTE plasmas rely on configurations approximate modelling or even supra-configurations modelling for mid Z plasmas. But in some cases, configurations interaction (either relativistic and non relativistic) induces dramatic changes in spectral shapes. We propose here a new detailed emissivity code with configuration mixing to allow for a realistic description of complex mid Z plasmas. A collisional radiative calculation. based on HULLAC precise energies and cross sections. determines the populations. Detailed emissivities and opacities are then calculated and radiative transfer equation is resolved for wide inhomogeneous plasmas. This code is able to cope rapidly with very large amount of atomic data. It is therefore possible to use complex hydrodynamic files even on personal computers in a very limited time. We used this code for comparison with Xenon EUV sources within the framework of nano-lithography developments. It appears that configurations mixing strongly shifts satellite lines and must be included in the description of these sources to enhance their efficiency. (author)

  12. Studies of plasma breakdown and electron heating on a 14 GHz ECR ion source through measurement of plasma bremsstrahlung

    Energy Technology Data Exchange (ETDEWEB)

    Ropponen, T; Machicoane, G; Leitner, D [National Superconducting Cyclotron Laboratory, MSU, East Lansing, MI 48824 (United States); Tarvainen, O; Toivanen, V; Koivisto, H; Kalvas, T; Peura, P; Jones, P [University of Jyvaeskylae, Department of Physics, PO Box 35 (YFL), 40500 Jyvaeskylae (Finland); Izotov, I; Skalyga, V; Zorin, V [Institute of Applied Physics, RAS, 46 Ulyanov St., 603950 Nizhny Novgorod (Russian Federation); Noland, J, E-mail: tommi.ropponen@gmail.com, E-mail: olli.tarvainen@jyu.fi [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States)

    2011-10-15

    Temporal evolution of plasma bremsstrahlung emitted by a 14 GHz electron cyclotron resonance ion source (ECRIS) operated in pulsed mode is presented in the energy range 1.5-400 keV with 100 {mu}s resolution. Such a high temporal resolution together with this energy range has never been measured before with an ECRIS. Data are presented as a function of microwave power, neutral gas pressure, magnetic field configuration and seed electron density. The saturation time of the bremsstrahlung count rate is almost independent of the photon energy up to 100 keV and exhibits similar characteristics with the neutral gas balance. The average photon energy during the plasma breakdown is significantly higher than that during the steady state and depends strongly on the density of seed electrons. The results are consistent with a theoretical model describing the evolution of the electron energy distribution function during the preglow transient.

  13. Plasma source by microwaves: design description

    International Nuclear Information System (INIS)

    Camps, E.; Olea, O.; Andrade, R.; Anguiano, G.

    1992-03-01

    The design of a device for the formation of a plasma with densities of the order of 10 12 cm - 3 and low temperatures (T e ∼ 40 eV) is described. For such purpose it was carried out in the device a microwave discharge (f o = 2.45 GHz) in a resonator of high Q factor, immersed in a static external magnetic field. The device worked in the regime ω ce ≤ ω o /2 (ω ce - cyclotron frequency of the electrons, (ω o = 2 π f o ) where is possible the excitement of non lineal phenomena of waves transformation. (Author)

  14. Spheroidal and toroidal configurations as sources of the Kerr metric. Pt. 1. A kinematical approach. [Boyer surface condition, singularity

    Energy Technology Data Exchange (ETDEWEB)

    de Felice, F; Nobili, L [Padua Univ. (Italy). Istituto di Fisica; Calvani, M [Padua univ. (Italy). Istituto di Astronomia

    1976-03-01

    The existence of extended Kerr metric sources of perfect fluid is taken as work-hypothesis to investigate the structure of the boundaries which derive from Boyer's surface condition. We find closed spheroidal configurations which hide an internal cavity as well as toroidal configurations; however, both the boundary of the internal cavity and the tori touch the ring singularity. We judge this feature non-physical and conclude that Boyer's condition is not sufficient to completely define a well behaved physical source.

  15. The isotope effect on divertor conditions and neutral pumping in horizontal divertor configurations in JET-ILW Ohmic plasmas

    Directory of Open Access Journals (Sweden)

    J. Uljanovs

    2017-08-01

    Full Text Available Understanding the impact of isotope mass and divertor configuration on the divertor conditions and neutral pressures is critical for predicting the performance of the ITER divertor in DT operation. To address this need, ohmically heated hydrogen and deuterium plasma experiments were conducted in JET with the ITER-like wall in varying divertor configurations. In this study, these plasmas are simulated with EDGE2D-EIRENE outfitted with a sub-divertor model, to predict the neutral pressures in the plenum with similar fashion to the experiments. EDGE2D-EIRENE predictions show that the increased isotope mass results in up to a 25% increase in peak electron densities and 15% increase in peak ion saturation current at the outer target in deuterium when compared to hydrogen for all horizontal divertor configurations. Indicating that a change from hydrogen to deuterium as main fuel decreases the neutral mean free path, leading to higher neutral density in the divertor. Consequently, this mechanism also leads to higher neutral pressures in the sub-divertor. The experimental data provided by the hydrogen and deuterium ohmic discharges shows that closer proximity of the outer strike point to the pumping plenum results in a higher neutral pressure in the sub-divertor. The diaphragm capacitance gauge pressure measurements show that a two to three-fold increase in sub-divertor pressure was achieved in the corner and nearby horizontal configurations compared to the far-horizontal configurations, likely due to ballistic transport (with respect to the plasma facing components of the neutrals into the sub-divertor. The corner divertor configuration also indicates that a neutral expansion occurs during detachment, resulting in a sub-divertor neutral density plateau as a function of upstream density at the outer-mid plane.

  16. A Comparison of Plasma Performance Between Single-Null and Double-Null Configurations During Elming H-Mode

    International Nuclear Information System (INIS)

    Petrie, T.W.; Fenstermacher, M.E.; Allen, S.L.; Carlstrom, T.N.; Gohil, P.; Groebner, R.J.; Greenfield, C.M.; Hyatt, A.W.; Lasnier, C.J.; La Haye, R.J.; Leonard, A.W.; Mahdavi, M.A.; Osborne, T.H.; Porter, G.D.; Rhodes, T.L.; Thomas, D.M.; Watkins, J.G.; West, W.P.; Wolf, N.S.

    1999-01-01

    Tokamak plasma performance generally improves with increased shaping of the plasma cross section, such as higher elongation and higher triangularity. The stronger shaping, especially higher triangularity, leads to changes in the magnetic topology of the divertor. Because there are engineering and divertor physics issues associated with changes in the details of the divertor flux geometry, especially as the configuration transitions from a single-null (SN) divertor to a marginally balanced double-null (DN) divertor, we have undertaken a systematic evaluation of the plasma characteristics as the magnetic geometry is varied, particularly with respect to (1) energy confinement, (2) the response of the plasma to deuterium gas fueling, (3) the operational density range for the ELMing H-mode, and (4) heat flux sharing by the diverters. To quantify the degree of divertor imbalance (or equivalently, to what degree the shape is double-null or single-null), we define a parameter DRSEP. DRSEP is taken as the radial distance between the upper divertor separatrix and the lower divertor separatrix, as determined at the outboard midplane. For example, if DRSEP=O, the configuration is a magnetically balanced DN; if DRSEP = +1.0 cm, the divertor configuration is biased toward the upper divertor. Three examples are shown in Fig. 1. In the following discussions, VB drift is directed toward the lower divertor

  17. Industrial application of electron sources with plasma emitters

    CERN Document Server

    Belyuk, S I; Rempe, N G

    2001-01-01

    Paper contains a description, operation, design and parameters of electron sources with plasma emitters. One presents examples of application of these sources as part of automated electron-beam welding lines. Paper describes application of such sources for electron-beam deposition of composite powders. Electron-beam deposition is used to rebuild worn out part and to increase strength of new parts of machines and tools. Paper presents some examples of rebuilding part and the advantages gained in this case

  18. Beam-plasma discharge in a Kyoto beam-plasma-ion source

    International Nuclear Information System (INIS)

    Ishikawa, J.; Takagi, T.

    1983-01-01

    A beam-plasma type ion source employing an original operating principle has been developed by the present authors. The ion source consists of an ion extraction region with an electron gun, a thin long drift tube as the plasma production chamber, and a primary electron beam collector. An electron beam is effectively utilized for the dual purpose of high density plasma production as a result of beam-plasma discharge, and high current ion beam extraction with ion space-charge compensation. A high density plasma of the order of 10 11 --10 13 cm -3 was produced by virtue of the beam-plasma discharge which was caused by the interaction between a space-charge wave on the electron beam and a high frequency plasma wave. The plasma density then produced was 10 2 --10 3 times the density produced only by collisional ionization by the electron beam. In order to obtain a stable beam-plasma discharge, a secondary electron beam emitted from the electron collector should be utilized. The mechanism of the beam-plasma discharge was analyzed by use of a linear theory in the case of the small thermal energy of the electron beam, and by use of a quasilinear theory in the case of the large thermal energy. High current ion beams of more than 0.1 A were extracted even at a low extraction voltage of 1--5 kV

  19. Development of the front end test stand and vessel for extraction and source plasma analyses negative hydrogen ion sources at the Rutherford Appleton Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Lawrie, S. R., E-mail: scott.lawrie@stfc.ac.uk [STFC ISIS Pulsed Spallation Neutron and Muon Facility, Rutherford Appleton Laboratory, Harwell Oxford, Harwell (United Kingdom); John Adams Institute of Accelerator Science, University of Oxford, Oxford (United Kingdom); Faircloth, D. C.; Letchford, A. P.; Perkins, M.; Whitehead, M. O.; Wood, T. [STFC ISIS Pulsed Spallation Neutron and Muon Facility, Rutherford Appleton Laboratory, Harwell Oxford, Harwell (United Kingdom); Gabor, C. [ASTeC Intense Beams Group, Rutherford Appleton Laboratory, Harwell Oxford, Harwell (United Kingdom); Back, J. [High Energy Physics Department, University of Warwick, Coventry (United Kingdom)

    2014-02-15

    The ISIS pulsed spallation neutron and muon facility at the Rutherford Appleton Laboratory (RAL) in the UK uses a Penning surface plasma negative hydrogen ion source. Upgrade options for the ISIS accelerator system demand a higher current, lower emittance beam with longer pulse lengths from the injector. The Front End Test Stand is being constructed at RAL to meet the upgrade requirements using a modified ISIS ion source. A new 10% duty cycle 25 kV pulsed extraction power supply has been commissioned and the first meter of 3 MeV radio frequency quadrupole has been delivered. Simultaneously, a Vessel for Extraction and Source Plasma Analyses is under construction in a new laboratory at RAL. The detailed measurements of the plasma and extracted beam characteristics will allow a radical overhaul of the transport optics, potentially yielding a simpler source configuration with greater output and lifetime.

  20. Application of a magnetized coaxial plasma gun for formation of a high-beta field-reversed configuration

    Energy Technology Data Exchange (ETDEWEB)

    Nishida, T. [College of Science and Technology, Nihon University, 1-8 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8308 (Japan); Kiguchi, T. [College of Science and Technology, Nihon University, 1-8 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8308 (Japan); Asai, T. [College of Science and Technology, Nihon University, 1-8 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8308 (Japan)]. E-mail: asai@phys.cst.nihon-u.ac.jp; Takahashi, T. [College of Science and Technology, Nihon University, 1-8 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8308 (Japan); Matsuzawa, Y. [College of Science and Technology, Nihon University, 1-8 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8308 (Japan); Okano, T. [College of Science and Technology, Nihon University, 1-8 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8308 (Japan); Nogi, Y. [College of Science and Technology, Nihon University, 1-8 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8308 (Japan)

    2006-11-15

    We have tested a field-reversed configuration (FRC) formation with a spheromak injection for the first time. In this method, initial pre-ionized plasma is injected as a magnetized spheromak-like plasmoid into the discharge chamber prior to main field reversal. The FRC plasma with an electron density of 1.3 x 10{sup 21} m{sup -3}, a separatrix radius of 0.04 m and a plasma length of 0.8 m was produced successfully in initial background plasma of about 1.6 x 10{sup 19} m{sup -3} by spheromak injection. The density is about one third of the conventional formed by the z-ionized method.

  1. Technical and experimental investigations of a plasma focus neutron source

    International Nuclear Information System (INIS)

    Rapp, H.K.

    The results obtained from two plasma-focus devices of different size allow to report on the technical and physical properties of such neutron flash sources. The results of some diagnostic methods used for the control of the gas discharge and for the measurement of the neutron production are included. The planning of plasma focus devices is illustrated with the aid of snow-plow calculations

  2. Performance evaluation of a permanent ring magnet based helicon plasma source for negative ion source research

    Science.gov (United States)

    Pandey, Arun; Bandyopadhyay, M.; Sudhir, Dass; Chakraborty, A.

    2017-10-01

    Helicon wave heated plasmas are much more efficient in terms of ionization per unit power consumed. A permanent magnet based compact helicon wave heated plasma source is developed in the Institute for Plasma Research, after carefully optimizing the geometry, the frequency of the RF power, and the magnetic field conditions. The HELicon Experiment for Negative ion-I source is the single driver helicon plasma source that is being studied for the development of a large sized, multi-driver negative hydrogen ion source. In this paper, the details about the single driver machine and the results from the characterization of the device are presented. A parametric study at different pressures and magnetic field values using a 13.56 MHz RF source has been carried out in argon plasma, as an initial step towards source characterization. A theoretical model is also presented for the particle and power balance in the plasma. The ambipolar diffusion process taking place in a magnetized helicon plasma is also discussed.

  3. Investigation of radiofrequency plasma sources for space travel

    International Nuclear Information System (INIS)

    Charles, C; Boswell, R W; Takahashi, K

    2012-01-01

    Optimization of radiofrequency (RF) plasma sources for the development of space thrusters differs from other applications such as plasma processing of materials since power efficiency, propellant usage, particle acceleration or heating become driving parameters. The development of two RF (13.56 MHz) plasma sources, the high-pressure (∼1 Torr) capacitively coupled ‘pocket rocket’ plasma micro-thruster and the low-pressure (∼1 mTorr) inductively coupled helicon double layer thruster (HDLT), is discussed within the context of mature and emerging electric propulsion devices. The density gradient in low-pressure expanding RF plasmas creates an electric field that accelerates positive ions out of the plasma. Generally, the total potential drop is similar to that of a wall sheath allowing the plasma electrons to neutralize the ion beam. A high-pressure expansion with no applied magnetic field can result in large dissociation rates and/or a collimated beam of ions of small area and a flowing heated neutral beam (‘pocket rocket’). A low-pressure expansion dominated by a magnetic field can result in the formation of electric double layers which produce a very directed neutralized beam of ions of large area (HDLT). (paper)

  4. Investigation of radiofrequency plasma sources for space travel

    Science.gov (United States)

    Charles, C.; Boswell, R. W.; Takahashi, K.

    2012-12-01

    Optimization of radiofrequency (RF) plasma sources for the development of space thrusters differs from other applications such as plasma processing of materials since power efficiency, propellant usage, particle acceleration or heating become driving parameters. The development of two RF (13.56 MHz) plasma sources, the high-pressure (˜1 Torr) capacitively coupled ‘pocket rocket’ plasma micro-thruster and the low-pressure (˜1 mTorr) inductively coupled helicon double layer thruster (HDLT), is discussed within the context of mature and emerging electric propulsion devices. The density gradient in low-pressure expanding RF plasmas creates an electric field that accelerates positive ions out of the plasma. Generally, the total potential drop is similar to that of a wall sheath allowing the plasma electrons to neutralize the ion beam. A high-pressure expansion with no applied magnetic field can result in large dissociation rates and/or a collimated beam of ions of small area and a flowing heated neutral beam (‘pocket rocket’). A low-pressure expansion dominated by a magnetic field can result in the formation of electric double layers which produce a very directed neutralized beam of ions of large area (HDLT).

  5. Characterization of DBD plasma source for biomedical applications

    Energy Technology Data Exchange (ETDEWEB)

    Kuchenbecker, M; Vioel, W [University of Applied Sciences and Arts, Faculty of Natural Sciences and Technology, Von-Ossietzky-Str. 99, 37085 Goettingen (Germany); Bibinov, N; Awakowicz, P [Institute for Electrical Engineering and Plasma Technology, Ruhr-Universitaet Bochum, Universitaetstr. 150, 44780 Bochum (Germany); Kaemlimg, A; Wandke, D, E-mail: m.kuchenbecker@web.d, E-mail: Nikita.Bibinov@rub.d, E-mail: awakowicz@aept-ruhr-uni-bochum.d, E-mail: vioel@hawk-hhg.d [CINOGY GmbH, Max-Naeder-Str. 15, 37114 Duderstadt (Germany)

    2009-02-21

    The dielectric barrier discharge (DBD) plasma source for biomedical application is characterized using optical emission spectroscopy, plasma-chemical simulation and voltage-current measurements. This plasma source possesses only one electrode covered by ceramic. Human body or some other object with enough high electric capacitance or connected to ground can serve as the opposite electrode. DBD consists of a number of microdischarge channels distributed in the gas gap between the electrodes and on the surface of the dielectric. To characterize the plasma conditions in the DBD source, an aluminium plate is used as an opposite electrode. Electric parameters, the diameter of microdischarge channel and plasma parameters (electron distribution function and electron density) are determined. The gas temperature is measured in the microdischarge channel and calculated in afterglow phase. The heating of the opposite electrode is studied using probe measurement. The gas and plasma parameters in the microdischarge channel are studied at varied distances between electrodes. According to an energy balance study, the input microdischarge electric energy dissipates mainly in heating of electrodes (about 90%) and partially (about 10%) in the production of chemical active species (atoms and metastable molecules).

  6. Simulation based investigation of source-detector configurations for non-invasive fetal pulse oximetry

    Directory of Open Access Journals (Sweden)

    Böttrich Marcel

    2015-09-01

    Full Text Available Transabdominal fetal pulse oximetry is a method to monitor the oxygen supply of the unborn child non-invasively. Due to the measurement setup, the received signal of the detector is composed of photons coding purely maternal and photons coding mixed fetal-maternal information. To analyze the wellbeing of the fetus, the fetal signal is extracted from the mixed component. In this paper we assess source-detector configurations, such that the mixed fetal-maternal components of the acquired signals are maximized. Monte-Carlo method is used to simulate light propagation and photon distribution in tissue. We use a plane layer and a spherical layer geometry to model the abdomen of a pregnant woman. From the simulations we extracted the fluence at the detector side for several source-detector distances and analyzed the ratio of the mixed fluence component to total fluence. Our simulations showed that the power of the mixed component depends on the source-detector distance as expected. Further we were able to visualize hot spot areas in the spherical layer model where the mixed fluence ratio reaches the highest level. The results are of high importance for sensor design considering signal composition and quality for non-invasive fetal pulse oximetry.

  7. Modeling of EUV emission from xenon and tin plasma sources for nanolithography

    Energy Technology Data Exchange (ETDEWEB)

    Poirier, M. [Service Photons, Atomes, et Molecules, CEA Saclay, bat. 522, F91191 Gif/Yvette Cedex (France)]. E-mail: michel.poirier@cea.fr; Blenski, T. [Service Photons, Atomes, et Molecules, CEA Saclay, bat. 522, F91191 Gif/Yvette Cedex (France); Gaufridy de Dortan, F. de [Service Photons, Atomes, et Molecules, CEA Saclay, bat. 522, F91191 Gif/Yvette Cedex (France); Gilleron, F. [CEA-DAM, F91680 Bruyeres-le-Chatel (France)

    2006-05-15

    Over the last decade there has been a major effort devoted to the development of efficient extreme UV sources designed for nanolithography, operating in the 13.5-nm range. Possible sources include laser-produced plasmas and discharge-produced plasmas. This paper, devoted to the modeling of such emission, emphasizes the atomic physics effects and particularly the effects of configuration interaction. Two types of theoretical approaches are presented, one involving the detailed computation with the parametric potential code HULLAC, the other based on the superconfiguration code SCO. Computations of emission spectra in xenon and tin are presented. The possible influence of non-local thermodynamic equilibrium (NLTE) effects is investigated using populations given by the simple collisional-radiative formulas from Colombant and Tonon. Convergence to LTE is analyzed in the tin case.

  8. Particle flux at the outlet of an Ecr plasma source

    International Nuclear Information System (INIS)

    Gutierrez T, C.; Gonzalez D, J.

    1999-01-01

    The necessity of processing big material areas this has resulted in the development of plasma sources with the important property to be uniform in these areas. Also the continuous diminution in the size of substrates to be processed have stimulated the study of models which allow to predict the control of energy and the density of the ions and neutral particles toward the substrate. On the other hand, there are other applications of the plasma sources where it is very necessary to understand the effects generated by the energetic fluxes of ions and neutrals. These fluxes as well as another beneficial effects can improve the activation energy for the formation and improvement of the diffusion processes in the different materials. In this work, using the drift kinetic approximation is described a model to calculate the azimuthal and radial fluxes in the zone of materials processing of an Ecr plasma source type. The results obtained are compared with experimental results. (Author)

  9. Microwave plasma source having improved switching operation from plasma ignition phase to normal ion extraction phase

    International Nuclear Information System (INIS)

    Sakudo, N.; Abe, K.; Koike, H.; Okada, O.; Tokiguchi, K.

    1985-01-01

    In a microwave plasma source, a discharge space supplied with a microwave electric field is supplied with a DC magnetic field. A material to be ionized is introduced into the discharge space to produce plasma, whereby ions are extracted through an ion extracting system. A switch is provided for effecting through switching operation the change-over of the magnetic field applied to the discharge space from the intensity for the ignition of plasma to the intensity for ion extraction in succession to completion of the plasma ignition

  10. Comparative study of atmospheric pressure low and radio frequency microjet plasmas produced in a single electrode configuration

    International Nuclear Information System (INIS)

    Kim, Dan Bee; Rhee, J. K.; Gweon, B.; Moon, S. Y.; Choe, W.

    2007-01-01

    Microsize jet-type plasmas were generated in a single pin electrode structure source for two separate input frequencies of 50 kHz and 13.56 MHz in the ambient air. The copper pin electrode radius was 360 μm, and it was placed in a Pyrex tube with a radius of 3 mm for helium gas supply. Due to the input frequency difference, the generated plasmas showed distinct discharge characteristics for their plasma physical appearances, electrical properties, gas temperatures, and optical properties. Strengths and weaknesses of both plasmas were discussed for further applications

  11. Impact of ECRH launcher flexibility on NTM stabilization and advanced scenarios in large toroidal configurations as JET plasmas

    International Nuclear Information System (INIS)

    Nowak, S.; Bruschi, A.; Ramponi, G.; Cirant, S.; Lazzaro, E.; Verhoeven, A.G.A.; Zohm, H.

    2003-01-01

    A beam-tracing code is used for extensive beam-tracing, ECCD and ECRH profile calculations in ideal JET-like plasmas with the main aim of specifying such crucial parameters for the ECRH launcher as the poloidal and toroidal steering ranges, the permitted error in the various launching angles and the optimal shape of the last mirrors reflecting surfaces. In order to be fusion-relevant, the calculations are performed on ideal target plasmas and equilibrium configurations scaled from real JET shots, selected by the JET-EP ECRH Physics Integration Project. The launching scheme is fully compliant with a launcher designed under the geometric constraints of JET, which consists of 6 to 8 beams arranged in pairs, with four end mirrors steerable both in the poloidal and in the toroidal directions. It is shown that with this arrangement all launching configurations requested by the physics goals of ECRH in a JET-like device are feasible. (authors)

  12. 21 CFR 640.64 - Collection of blood for Source Plasma.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Collection of blood for Source Plasma. 640.64... (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Source Plasma § 640.64 Collection of blood for Source Plasma. (a) Supervision. All blood for the collection of Source Plasma shall...

  13. Development of negative heavy ion sources for plasma potential measurement

    International Nuclear Information System (INIS)

    Sasao, M.; Okabe, Y.; Fujisawa, A.; Iguchi, H.; Fujita, J.; Yamaoka, H.; Wada, M.

    1991-10-01

    A plasma sputter negative ion source was studied for its applicability to the potential measurement of a fusion plasma. Both the beam current density and the beam energy spread are key issues. Energy spectra of a self extracted Au - beam from the source were measured under the condition of a constant work function of the production surface. The full width of half maximum (FWHM) increases from 3 eV to 9 eV monotonically as the target voltage increases from 50 V to 300 V, independently from the target surface work function of 2.2 - 3 eV. (author)

  14. Plasma source ion implantation research at southwestern institute of physics

    International Nuclear Information System (INIS)

    Shang Zhenkui; Geng Man; Tong Honghui

    1997-10-01

    The PSII-EX device and PSII-IM device for research and development of plasma source ion implantation (PSII) technology are described briefly. The functions, main technical specifications and properties of the devices are also discussed. After ion implantation by PSII, the improvements of the surface-mechanical properties (such as microhardness, wear-resistance, friction factor, biological compatibility, etc) for some materials, microanalysis and numerical simulation of modified layers of materials, the technical developments for the practical workpiece treatments and the preliminary experiments for plasma source ion implantation-enhanced deposition are introduced too. As last, the future work about PSII have been proposed

  15. Evaluation and Optimization of Electrode Configuration of Multi-Channel Corona Discharge Plasma for Dye-Containing Wastewater Treatment

    International Nuclear Information System (INIS)

    Ren Jingyu; Qu Guangzhou; Liang Dongli; Hu Shibin; Wang Tiecheng

    2015-01-01

    A discharge plasma reactor with a point-to-plane structure was widely studied experimentally in wastewater treatment. In order to improve the utilization efficiency of active species and the energy efficiency of this kind of discharge plasma reactor during wastewater treatment, the electrode configuration of the point-to-plane corona discharge reactor was studied by evaluating the effects of discharge spacing and adjacent point distance on discharge power and discharge energy density, and then dye-containing wastewater decoloration experiments were conducted on the basis of the optimum electrode configuration. The experimental results of the discharge characteristics showed that high discharge power and discharge energy density were achieved when the ratio of discharge spacing to adjacent point distance (d/s) was 0.5. Reactive Brilliant Blue (RBB) wastewater treatment experiments presented that the highest RBB decoloration efficiency was observed at d/s of 0.5, which was consistent with the result obtained in the discharge characteristics experiments. In addition, the biodegradability of RBB wastewater was enhanced greatly after discharge plasma treatment under the optimum electrode configuration. RBB degradation processes were analyzed by GC-MS and IC, and the possible mechanism for RBB decoloration was also discussed. (paper)

  16. The ionization length in plasmas with finite temperature ion sources

    Science.gov (United States)

    Jelić, N.; Kos, L.; Tskhakaya, D. D.; Duhovnik, J.

    2009-12-01

    The ionization length is an important quantity which up to now has been precisely determined only in plasmas which assume that the ions are born at rest, i.e., in discharges known as "cold ion-source" plasmas. Presented here are the results of our calculations of the ionization lengths in plasmas with an arbitrary ion source temperature. Harrison and Thompson (H&T) [Proc. Phys. Soc. 74, 145 (1959)] found the values of this quantity for the cases of several ion strength potential profiles in the well-known Tonks-Langmuir [Phys. Rev. 34, 876 (1929)] discharge, which is characterized by "cold" ion temperature. This scenario is also known as the "singular" ion-source discharge. The H&T analytic result covers cases of ion sources proportional to exp(βΦ) with Φ the normalized plasma potential and β =0,1,2 values, which correspond to particular physical scenarios. Many years following H&T's work, Bissell and Johnson (B&J) [Phys. Fluids 30, 779 (1987)] developed a model with the so-called "warm" ion-source temperature, i.e., "regular" ion source, under B&J's particular assumption that the ionization strength is proportional to the local electron density. However, it appears that B&J were not interested in determining the ionization length at all. The importance of this quantity to theoretical modeling was recognized by Riemann, who recently answered all the questions of the most advanced up-to-date plasma-sheath boundary theory with cold ions [K.-U. Riemann, Phys. Plasmas 13, 063508 (2006)] but still without the stiff warm ion-source case solution, which is highly resistant to solution via any available analytic method. The present article is an extension of H&T's results obtained for a single point only with ion source temperature Tn=0 to arbitrary finite ion source temperatures. The approach applied in this work is based on the method recently developed by Kos et al. [Phys. Plasmas 16, 093503 (2009)].

  17. Plasma properties of a modified beam-plasma type ion source

    International Nuclear Information System (INIS)

    Ishikawa, Junzo; Sano, Fumimichi; Tsuji, Hiroshi; Ektessabi, A.M.; Takagi, Toshinori

    1978-01-01

    The properties of the plasma produced by beam-plasma discharge were experimentally investigated. The ion source used for this work consists of three parts, that is, the ion-extracting region with an electron gun, the drift space and the collector region. Primary and secondary electron beams are injected in to the drift tube. The interaction between plasma and these electron beams causes production of high density plasma by virtue of the beam-plasma discharge. The gas inlet is located in the middle of the drift tube, so that the gas conductance is high. The energy of the primary and secondary electron beams is transferred to that microwaves through beam-plasma interaction. The microwaves heat the plasma electrons by the cyclotron resonance or other mechanism. The amount of the energetic plasma electrons is much larger than that of the beam electrons, so that neutral gas is ionized. The density of the produced plasma is 10 2 or 10 3 times as large as the plasma produced by impact ionization. With a probe located in the middle of the drift tube, the plasma density and the electron temperature can be measured, and the power and spectra of the microwaves can be detected. The microwave oscillation, the primary electron beam characteristics, and the gas pressure characteristics were studied. Larger current of the high energy primary of secondary electron beam is required for the effective discharge. The ion source has to be operated at the minimum gas pressure. The length of beam-plasma interaction and the magnetic field intensity in the drift tube are also important parameters. (Kato, T.)

  18. Investigation of rf plasma light sources for dye laser excitation

    International Nuclear Information System (INIS)

    Kendall, J.S.; Jaminet, J.F.

    1975-06-01

    Analytical and experimental studies were performed to assess the applicability of radio frequency (rf) induction heated plasma light sources for potential excitation of continuous dye lasers. Experimental efforts were directed toward development of a continuous light source having spectral flux and emission characteristics approaching that required for pumping organic dye lasers. Analytical studies were performed to investigate (1) methods of pulsing the light source to obtain higher radiant intensity and (2) methods of integrating the source with a reflective cavity for pumping a dye cell. (TFD)

  19. Pulsed, Inductively Generated, Streaming Plasma Ion Source for Heavy Ion Fusion Linacs

    International Nuclear Information System (INIS)

    Steven C. Glidden; Howard D Sanders; John B. Greenly; Daniel L. Dongwoo

    2006-01-01

    This report describes a compact, high current density, pulsed ion source, based on electrodeless, inductively driven gas breakdown, developed to meet the requirements on normalized emittance, current density, uniformity and pulse duration for an ion injector in a heavy-ion fusion driver. The plasma source produces >10 (micro)s pulse of Argon plasma with ion current densities >100 mA/cm2 at 30 cm from the source and with strongly axially directed ion energy of about 80 eV, and sub-eV transverse temperature. The source has good reproducibility and spatial uniformity. Control of the current density during the pulse has been demonstrated with a novel modulator coil method which allows attenuation of the ion current density without significantly affecting the beam quality. This project was carried out in two phases. Phase 1 used source configurations adapted from light ion sources to demonstrate the feasibility of the concept. In Phase 2 the performance of the source was enhanced and quantified in greater detail, a modulator for controlling the pulse shape was developed, and experiments were conducted with the ions accelerated to >40 kV

  20. Discharge regimes and density jumps in a helicon plasma source

    International Nuclear Information System (INIS)

    Shinohara, S.; Yonekura, K.

    1999-01-01

    A high density plasma source using a helicon wave is becoming very attractive in plasma processing and confinement devices. In the previous work, the characteristics of this wave and plasma performance with diameters of 5 and 45 cm have been studied, and the helicon wave was only observed after the density jump. Recently, density jumps from the low to high electron densities with a level of 10 13 cm -3 were investigated by changing the antenna wavenumber spectrum, and the obtained results were compared with the inductively coupled plasma (ICP). However, the mechanisms of density jumps and plasma production are still open questions to be answered. Here, the authors try to investigate the discharge regimes and density jumps in a helicon plasma source, by changing the antenna wavenumber spectrum. For he case of the parallel current directions in the antenna, where the low wavenumber spectrum part is large, the density jump was observed with the low RF input power of P in < 300 W regardless of the magnetic field. On the other hand, for the case of the opposite directions, where the low wavenumber spectrum part is small, the threshold power to obtain the jump became high with the increase in the magnetic field. This can be understood from the dispersion relation of the helicon wave. The wave structures and the dispersion relations in the discharge modes will be also shown

  1. Plasmas in compact traps: From ion sources to multidisciplinary research

    Science.gov (United States)

    Mascali, D.; Musumarra, A.; Leone, F.; Galatà, A.; Romano, F. P.; Gammino, S.

    2017-09-01

    In linear (minimum-B) magneto-static traps dense and hot plasmas are heated by electromagnetic radiation in the GHz domain via the Electron Cyclotron Resonance (ECR). The values of plasma density, temperature and confinement times ( n_eτ_i>10^{13} cm ^{-3} s; T_e>10 keV) are similar to the ones of thermonuclear plasmas. The research in this field -devoted to heating and confinement optimization- has been supported by numerical modeling and advanced diagnostics, for probing the plasma especially in a non-invasive way. ECR-based systems are nowadays able to produce extremely intense (tens or hundreds of mA) beams of light ions (p, d, He), and relevant currents of heavier elements (C, O, N) up to heavy ions like Xe, Pb, U. Such beams can be extracted from the trap by a proper electrostatic system. The above-mentioned properties make these plasmas very attractive for interdisciplinary researches also, such as i) nuclear decays rates measurements in stellar-like conditions, ii) energy conversion studies, being exceptional sources of short-wavelength electromagnetic radiation (EUV, X-rays, hard X-rays and gammas, useful in material science and archaeometry), iii) environments allowing precise spectroscopical measurements as benchmarks for magnetized astrophysical plasmas. The talk will give an overview about the state-of-the-art in the field of intense ion sources, and some new perspectives for interdisciplinary research, with a special attention to the developments based at INFN-LNS.

  2. Characterization of atomic oxygen from an ECR plasma source

    International Nuclear Information System (INIS)

    Naddaf, M; Bhoraskar, V N; Mandale, A B; Sainkar, S R; Bhoraskar, S V

    2002-01-01

    A low-power microwave-assisted electron cyclotron resonance (ECR) plasma system is shown to be a powerful and effective source of atomic oxygen (AO) useful in material processing. A 2.45 GHz microwave source with maximum power of 600 W was launched into the cavity to generate the ECR plasma. A catalytic nickel probe was used to determine the density of AO. The density of AO is studied as a function of pressure and axial position of the probe in the plasma chamber. It was found to vary from ∼1x10 20 to ∼10x10 20 atom m -3 as the plasma pressure was varied from 0.8 to 10 mTorr. The effect of AO in oxidation of silver is investigated by gravimetric analysis. The stoichiometric properties of the oxide are studied using the x-ray photoelectron spectroscopy as well as energy dispersive x-ray analysis. The degradation of the silver surface due to sputtering effect was viewed by scanning electron spectroscopy. The sputtering yield of oxygen ions in the plasma is calculated using the TRIM code. The effects of plasma pressure and the distance from the ECR zone on the AO density were also investigated. The density of AO measured by oxidation of silver is in good agreement with results obtained from the catalytic nickel probe

  3. Characterization of atomic oxygen from an ECR plasma source

    Science.gov (United States)

    Naddaf, M.; Bhoraskar, V. N.; Mandale, A. B.; Sainkar, S. R.; Bhoraskar, S. V.

    2002-11-01

    A low-power microwave-assisted electron cyclotron resonance (ECR) plasma system is shown to be a powerful and effective source of atomic oxygen (AO) useful in material processing. A 2.45 GHz microwave source with maximum power of 600 W was launched into the cavity to generate the ECR plasma. A catalytic nickel probe was used to determine the density of AO. The density of AO is studied as a function of pressure and axial position of the probe in the plasma chamber. It was found to vary from ~1×1020 to ~10×1020 atom m-3 as the plasma pressure was varied from 0.8 to 10 mTorr. The effect of AO in oxidation of silver is investigated by gravimetric analysis. The stoichiometric properties of the oxide are studied using the x-ray photoelectron spectroscopy as well as energy dispersive x-ray analysis. The degradation of the silver surface due to sputtering effect was viewed by scanning electron spectroscopy. The sputtering yield of oxygen ions in the plasma is calculated using the TRIM code. The effects of plasma pressure and the distance from the ECR zone on the AO density were also investigated. The density of AO measured by oxidation of silver is in good agreement with results obtained from the catalytic nickel probe.

  4. Characterization of atomic oxygen from an ECR plasma source

    Energy Technology Data Exchange (ETDEWEB)

    Naddaf, M [Center for Advanced Studies in Material Science and Solid State Physics, University of Pune, Pune 411 007 (India); Bhoraskar, V N [Center for Advanced Studies in Material Science and Solid State Physics, University of Pune, Pune 411 007 (India); Mandale, A B [National Chemical Laboratory, Pashan, Pune 411008 (India); Sainkar, S R [National Chemical Laboratory, Pashan, Pune 411008 (India); Bhoraskar, S V [Center for Advanced Studies in Material Science and Solid State Physics, University of Pune, Pune 411 007 (India)

    2002-11-01

    A low-power microwave-assisted electron cyclotron resonance (ECR) plasma system is shown to be a powerful and effective source of atomic oxygen (AO) useful in material processing. A 2.45 GHz microwave source with maximum power of 600 W was launched into the cavity to generate the ECR plasma. A catalytic nickel probe was used to determine the density of AO. The density of AO is studied as a function of pressure and axial position of the probe in the plasma chamber. It was found to vary from {approx}1x10{sup 20} to {approx}10x10{sup 20} atom m{sup -3} as the plasma pressure was varied from 0.8 to 10 mTorr. The effect of AO in oxidation of silver is investigated by gravimetric analysis. The stoichiometric properties of the oxide are studied using the x-ray photoelectron spectroscopy as well as energy dispersive x-ray analysis. The degradation of the silver surface due to sputtering effect was viewed by scanning electron spectroscopy. The sputtering yield of oxygen ions in the plasma is calculated using the TRIM code. The effects of plasma pressure and the distance from the ECR zone on the AO density were also investigated. The density of AO measured by oxidation of silver is in good agreement with results obtained from the catalytic nickel probe.

  5. Experimental investigation of thermal limits in parallel plate configuration for the Advanced Neutron Source Reactor

    International Nuclear Information System (INIS)

    Siman-Tov, M.; Felde, D.K.; Kaminaga, M.; Yoder, G.L.

    1993-01-01

    The Advanced Neutron Source Reactor (ANSR) is currently being designed to become the world's highest-flux, steady-state, thermal neutron source for scientific experiments. Highly subcooled, heavy-water coolant flows vertically upward at a very high velocity of 25 m/s through parallel aluminum fuel-plates. The core has average and peak heat fluxes of 5.9 and 12 MW/m 2 , respectively. In this configuration, both flow excursion (FE) and true critical heat flux (CHF), represent potential thermal limitations. The availability of experimental data for both FE and true CHF at the conditions applicable to the ANSR is very limited. A Thermal Hydraulic Test Loop (THTL) facility was designed and built to simulate a full-length coolant subchannel of the core, allowing experimental determination of both thermal limits under the expected ANSR T/H conditions. A series of FE tests with water flowing vertically upward was completed over a nominal heat flux range of 6 to 14 MW/m 2 and a corresponding velocity range of 8 to 21 m/s. Both the exit pressure (1.7 MPa) and inlet temperature (45 degrees C) were maintained constant for these tests, while the loop was operated in a ''stiff''(constant flow) mode. Limited experiments were also conducted at 12 MW/m 2 using a ''soft'' mode (near constant pressure-drop) for actual FE burnout tests and using a ''stiff' mode for true CHF tests, to compare with the original FE experiments

  6. Electron Beam Diagnosis and Dynamics using DIADYN Plasma Source

    Energy Technology Data Exchange (ETDEWEB)

    Toader, D; Craciun, G; Manaila, E; Oproiu, C [National Institute of Research for Laser, Plasma and Radiation Physics Bucuresti (Romania); Marghitu, S [ICPE Electrostatica S.A - Bucuresti (Romania)

    2009-11-15

    This paper is presenting results obtained with the DIADYN installation after replacing its vacuum electron source (VES{sub L}V) with a plasma electron source (PES{sub L}V). DIADYN is a low energy laboratory equipment operating with 10 to 50 keV electron beams and designed to help realize non-destructive diagnosis and dynamics for low energy electron beams but also to be used in future material irradiations. The results presented here regard the beam diagnosis and dynamics made with beams obtained from the newly replaced plasma source. We discuss both results obtained in experimental dynamics and dynamics calculation results for electron beams extracted from the SEP{sub L}V source.

  7. Operation of Ferroelectric Plasma Sources in a Gas Discharge Mode

    International Nuclear Information System (INIS)

    Dunaevsky, A.; Fisch, N.J.

    2004-01-01

    Ferroelectric plasma sources in vacuum are known as sources of ablative plasma, formed due to surface discharge. In this paper, observations of a gas discharge mode of operation of the ferroelectric plasma sources (FPS) are reported. The gas discharge appears at pressures between approximately 20 and approximately 80 Torr. At pressures of 1-20 Torr, there is a transition from vacuum surface discharge to the gas discharge, when both modes coexist and the surface discharges sustain the gas discharge. At pressures between 20 and 80 Torr, the surface discharges are suppressed, and FPS operate in pure gas discharge mode, with the formation of almost uniform plasma along the entire surface of the ceramics between strips. The density of the expanding plasma is estimated to be about 1013 cm-3 at a distance of 5.5 mm from the surface. The power consumption of the discharge is comparatively low, making it useful for various applications. This paper also presents direct measurements of the yield of secondary electron emission from ferroelectric ceramics, which, at low energies of primary electrons, is high and dependent on the polarization of the ferroelectric material

  8. Plasma source ion implantation of ammonia into electroplated chromium

    International Nuclear Information System (INIS)

    Scheuer, J.T.; Walter, K.C.; Rej, D.J.; Nastasi, M.; Blanchard, J.P.

    1995-01-01

    Ammonia gas (NH 3 ) has been used as a nitrogen source for plasma source ion implantation processing of electroplated chromium. No evidence was found of increased hydrogen concentrations in the bulk material, implying that ammonia can be used without risking hydrogen embrittlement. The retained nitrogen dose of 2.1 x 10 17 N-at/cm 2 is sufficient to increase the surface hardness of electroplated Cr by 24% and decrease the wear rate by a factor of 4

  9. Enhanced confinement in electron cyclotron resonance ion source plasma.

    Science.gov (United States)

    Schachter, L; Stiebing, K E; Dobrescu, S

    2010-02-01

    Power loss by plasma-wall interactions may become a limitation for the performance of ECR and fusion plasma devices. Based on our research to optimize the performance of electron cyclotron resonance ion source (ECRIS) devices by the use of metal-dielectric (MD) structures, the development of the method presented here, allows to significantly improve the confinement of plasma electrons and hence to reduce losses. Dedicated measurements were performed at the Frankfurt 14 GHz ECRIS using argon and helium as working gas and high temperature resistive material for the MD structures. The analyzed charge state distributions and bremsstrahlung radiation spectra (corrected for background) also clearly verify the anticipated increase in the plasma-electron density and hence demonstrate the advantage by the MD-method.

  10. Operation of the ORNL High Particle Flux Helicon Plasma Source

    International Nuclear Information System (INIS)

    Goulding, Richard Howell; Biewer, Theodore M.; Caughman, John B.; Chen, Guangye; Owen, Larry W.; Sparks, Dennis O.

    2011-01-01

    A high power, high particle flux rf-based helicon plasma source has been constructed at ORNL and operated at power levels up to 30 kW. High-density hydrogen and helium plasmas have been produced. The source has been designed as the basis for a linear plasma materials interaction (PMI) test facility that will generate particle fluxes Gamma(p) > 10(23) M-3 s(-1), and utilize additional ion and electron cyclotron heating to produce high parallel (to the magnetic field) heat fluxes of similar to 10 MW/m(2). An rf-based source for PMI research is of interest because high plasma densities are generated with no internal electrodes, allowing true steady state operation with minimal impurity generation. The ORNL helicon source has a diameter of 15 cm and to-date has operated at a frequency f = 13.56 MHz, with magnetic field strength vertical bar B vertical bar in the antenna region up to similar to 0.15 T. Maximum densities of 3 x 10(19) M-3 in He and 2.5 x 10(19) m(-3) in H have been achieved. Radial density profiles have been seen to be dependent on the axial vertical bar B vertical bar profile.

  11. Operation of the ORNL High Particle Flux Helicon Plasma Source

    International Nuclear Information System (INIS)

    Goulding, R. H.; Biewer, T. M.; Caughman, J. B. O.; Chen, G. C.; Owen, L. W.; Sparks, D. O.

    2011-01-01

    A high power, high particle flux rf-based helicon plasma source has been constructed at ORNL and operated at power levels up to 30 kW. High-density hydrogen and helium plasmas have been produced. The source has been designed as the basis for a linear plasma materials interaction (PMI) test facility that will generate particle fluxes Γ p 10 23 m -3 s -1 , and utilize additional ion and electron cyclotron heating to produce high parallel (to the magnetic field) heat fluxes of ∼10 MW/m 2 . An rf-based source for PMI research is of interest because high plasma densities are generated with no internal electrodes, allowing true steady state operation with minimal impurity generation. The ORNL helicon source has a diameter of 15 cm and to-date has operated at a frequency f = 13.56 MHz, with magnetic field strength |B| in the antenna region up to ∼0.15 T. Maximum densities of 3x10 19 m -3 in He and 2.5x10 19 m -3 in H have been achieved. Radial density profiles have been seen to be dependent on the axial |B| profile.

  12. A general framework to select working fluid and configuration of ORCs for low-to-medium temperature heat sources

    International Nuclear Information System (INIS)

    Vivian, Jacopo; Manente, Giovanni; Lazzaretto, Andrea

    2015-01-01

    Highlights: • General guidelines are proposed to select ORC working fluid and cycle layout. • Distance between critical and heat source temperature for optimal fluid selection. • Separate contributions of cycle efficiency and heat recovery factor. - Abstract: The selection of the most suitable working fluid and cycle configuration for a given heat source is a fundamental step in the search for the optimum design of Organic Rankine Cycles. In this phase cycle efficiency and heat source recovery factor lead to opposite design choices in the achievement of maximum system efficiency and, in turn, maximum power output. In this work, both separate and combined effects of these two performance factors are considered to supply a thorough understanding of the compromise resulting in maximum performance. This goal is pursued by carrying out design optimizations of four different ORC configurations operating with twenty-seven working fluids and recovering heat from sensible heat sources in the temperature range 120–180 °C. Optimum working fluids and thermodynamic parameters are those which simultaneously allow high cycle efficiency and high heat recovery from the heat source to be obtained. General guidelines are suggested to reach this target for any system configuration. The distance between fluid critical temperature and inlet temperature of the heat source is found to play a key role in predicting the optimum performance of all system configurations regardless of the inlet temperature of the heat source

  13. Characteristics of an elongated plasma column produced by magnetically coupled hollow cathode plasma source

    Science.gov (United States)

    Bhuva, M. P.; Karkari, S. K.; Kumar, Sunil

    2018-03-01

    An elongated plasma column in the presence of an axial magnetic field has been formed using a cylindrical hollow cathode (HC) and a constricted anode (CA). The plasma characteristics of the central line have been found to vary with the magnetic field strength and the axial distance from the source. It is believed that the primary electrons constituting the discharge current are steered by the axial magnetic field to undertake ionizing collisions along the plasma column. The current carrying electrons from the HC reach the anode by cross-field diffusion towards the central line. The above observation has been substantiated using a phenomenological model which links the observed characteristics of the source with the plasma column. The experimental results are found to be in qualitative agreement with the model.

  14. Optical emission spectra of a copper plasma produced by a metal vapour vacuum arc plasma source

    International Nuclear Information System (INIS)

    Yotsombat, B.; Poolcharuansin, P.; Vilaithong, T.; Davydov, S.; Brown, I.G.

    2001-01-01

    Optical emission spectroscopy in the range 200-800 nm was applied for investigation of the copper plasma produced by a metal vapour vacuum arc plasma source. The experiments were conducted for the cases when the plasma was guided by straight and Ω-shaped curved solenoids as well as without solenoids, and also for different vacuum conditions. It was found that, besides singly- and doubly-charged ions, a relatively high concentration of excited neutral copper atoms was present in the plasma. The relative fraction of excited atoms was much higher in the region close to the cathode surface than in the plasma column inside the solenoid. The concentration of excited neutral, singly- and doubly-ionized atoms increased proportionally when the arc current was increased to 400 A. Some weak lines were attributed to more highly ionized copper species and impurities in the cathode material. (author)

  15. Development of intense pulsed heavy ion beam diode using gas puff plasma gun as ion source

    International Nuclear Information System (INIS)

    Ito, H.; Higashiyama, M.; Takata, S.; Kitamura, I.; Masugata, K.

    2006-01-01

    A magnetically insulated ion diode with an active ion source of a gas puff plasma gun has been developed in order to generate a high-intensity pulsed heavy ion beam for the implantation process of semiconductors and the surface modification of materials. The nitrogen plasma produced by the plasma gun is injected into the acceleration gap of the diode with the external magnetic field system. The ion diode is operated at diode voltage approx. =200 kV, diode current approx. =2 kA and pulse duration approx. =150 ns. A new acceleration gap configuration for focusing ion beam has been designed in order to enhance the ion current density. The experimental results show that the ion current density is enhanced by a factor of 2 and the ion beam has the ion current density of 27 A/cm 2 . In addition, the coaxial type Marx generator with voltage 200 kV and current 15 kA has been developed and installed in the focus type ion diode. The ion beam of ion current density approx. =54 A/cm 2 is obtained. To produce metallic ion beams, an ion source by aluminum wire discharge has been developed and the aluminum plasma of ion current density ∼70 A/cm 2 is measured. (author)

  16. Electromagnetic diagnostics of ECR-Ion Sources plasmas: optical/X-ray imaging and spectroscopy

    Science.gov (United States)

    Mascali, D.; Castro, G.; Altana, C.; Caliri, C.; Mazzaglia, M.; Romano, F. P.; Leone, F.; Musumarra, A.; Naselli, E.; Reitano, R.; Torrisi, G.; Celona, L.; Cosentino, L. G.; Giarrusso, M.; Gammino, S.

    2017-12-01

    Magnetoplasmas in ECR-Ion Sources are excited from gaseous elements or vapours by microwaves in the range 2.45-28 GHz via Electron Cyclotron Resonance. A B-minimum, magnetohydrodynamic stable configuration is used for trapping the plasma. The values of plasma density, temperature and confinement times are typically ne= 1011-1013 cm-3, 01 eVSilicon Drift detectors with high energy resolution of 125 eV at 5.9 keV have been used for the characterization of plasma emission at 02plasmas have been measured for different values of neutral pressure, microwave power and magnetic field profile (they are critical for high-power proton sources).

  17. Linked tandem mirror configuration as a possible steady state high β plasma container

    International Nuclear Information System (INIS)

    Ikuta, Kazunari.

    1982-04-01

    A possibility of achieving steady state high β plasma confinement in toroidal geometry is considered in detail by closing off the ends of tandem mirrors entirely by flux bridges, where β is the ratio of plasma pressure to the magnetic pressure. The key problem of this approach seems to be the magnetic design of magneto-hydrodynamically stabilized, preferentially leaky bridges. (author)

  18. Equilibrium and stability of a toroidal-sector plasma discharge in an EXTRAP configuration

    International Nuclear Information System (INIS)

    Drake, J.R.

    1982-02-01

    Experimental studies of the equilibrium and stability of a sector of a toroidal EXTRAP plasma discharge have been studied. The high β plasma discharge, which had an Alfven transit time about 0.5 μsec, could be positioned in a stable equilibrium for the 300μsec time scale of the experiment. (author)

  19. ECR plasma source for heavy ion beam charge neutralization

    Science.gov (United States)

    Efthimion, Philip C.; Gilson, Erik; Grisham, Larry; Kolchin, Pavel; Davidson, Ronald C.; Yu, Simon; Logan, B. Grant

    2003-01-01

    Highly ionized plasmas are being considered as a medium for charge neutralizing heavy ion beams in order to focus beyond the space-charge limit. Calculations suggest that plasma at a density of 1 100 times the ion beam density and at a length [similar]0.1 2 m would be suitable for achieving a high level of charge neutralization. An Electron Cyclotron Resonance (ECR) source has been built at the Princeton Plasma Physics Laboratory (PPPL) to support a joint Neutralized Transport Experiment (NTX) at the Lawrence Berkeley National Laboratory (LBNL) to study ion beam neutralization with plasma. The ECR source operates at 13.6 MHz and with solenoid magnetic fields of 1 10 gauss. The goal is to operate the source at pressures [similar]10[minus sign]6 Torr at full ionization. The initial operation of the source has been at pressures of 10[minus sign]4 10[minus sign]1 Torr. Electron densities in the range of 108 to 1011 cm[minus sign]3 have been achieved. Low-pressure operation is important to reduce ion beam ionization. A cusp magnetic field has been installed to improve radial confinement and reduce the field strength on the beam axis. In addition, axial confinement is believed to be important to achieve lower-pressure operation. To further improve breakdown at low pressure, a weak electron source will be placed near the end of the ECR source. This article also describes the wave damping mechanisms. At moderate pressures (> 1 mTorr), the wave damping is collisional, and at low pressures (< 1 mTorr) there is a distinct electron cyclotron resonance.

  20. Grid system design on the plasma cathode electron source

    International Nuclear Information System (INIS)

    Agus Purwadi

    2014-01-01

    It has been designed the grid system on the Plasma Cathode Electron Source (PCES). Grid system with the electron emission hole of (15 x 60) cm 2 , the single aperture grid size of (0,5 x O,5) mm 2 and the grid wire diameter of 0,25 mm, will be used on the plasma generator chamber. If the sum of grid holes known and the value of electron emission current through every the grid hole known too then the total value of electron emission Current which emits from the plasma generator chamber can be determined It has been calculated the value of electron emission current I e as function of the grid radius r e =(0.28, 0.40, 0.49, 0.56, 0.63, 0.69) mm on the electron temperature of T e = 5 eV for varying of the value plasma electron densities n e = (10 15 , 10 16 , 10 17 , 10 18 ) m -3 . Also for the value of electron emission current fe as function of the grid radius r e = (0.28, 0.40, 0.49. 0.56, 0.63,0.69) mm on the electron density n e = 10 17 m -3 for varying of the value of plasma electron temperatures T e = (1, 2, 3, 4, 5) eV. electron emission current will be increase by increasing grid radius, electron temperature as well as plasma electron density. (author)

  1. Tailoring of materials by atomic oxygen from ECR plasma source

    International Nuclear Information System (INIS)

    Naddaf, Munzer; Bhoraskar, S.V.

    2002-01-01

    Full text: An intense source of oxygen finds important applications in many areas of science, technology and industry. It has been successfully used for surface activation and cleaning in the electronic, chemical and automotive industries. Atomic oxygen and interaction with materials have also a significant importance in space science and technology. This paper describes the detailed studies related to the surface modification and processing of different materials, which include metals and polymers by atomic oxygen produced in microwave assisted electron cyclotron resonance plasma. The energy distribution of ions was measured as a function of plasma parameters and density measurements were supplemented by catalytic probe using nickel and oxidation of silver surface

  2. Impurity radiation from a beam-plasma neutron source

    International Nuclear Information System (INIS)

    Molvik, A.W.

    1995-01-01

    Impurity radiation, in a worst case evaluation for a beam-plasma neutron source (BPNS), does not limit performance. Impurities originate from four sources: (a) sputtering from walls by charge exchange or alpha particle bombardment, (b) sputtering from limiters, (c) plasma desorption of gas from walls and (d) injection with neutral beams. Sources (c) and (d) are negligible; adsorbed gas on the walls of the confinement chamber and the neutral beam sources is removed by the steady state discharge. Source (b) is negligible for impinging ion energies below the sputtering threshold (T i ≤ 0.025 keV on tungsten) and for power densities to the limiter within the capabilities of water cooling (30-40 MW/m 2 ); both conditions can be satisfied in the BPNS. Source (a) radiates 0.025 MW/m 2 to the neutron irradiation samples, compared with 5 to 10 MW/m 2 of neutrons; and radiates a total of 0.08 MW from the plasma column, compared with 60 MW of injected power. The particle bombardment that yields source (a) deposits an average of 2.7 MW/m 2 on the samples, within the capabilities of helium gas cooling (10 MW/m 2 ). An additional worst case for source (d) is evaluated for present day 2 to 5 s pulsed neutral beams with 0.1% impurity density and is benchmarked against 2XIIB. The total radiation would increase a factor of 1.5 to ≤ 0.12 MW, supporting the conclusion that impurities will not have a significant impact on a BPN. (author). 61 refs, 7 figs, 2 tabs

  3. A self-organized plasma with induction, reconnection, and injection techniques: the SPIRIT concept for field reversed configuration research

    International Nuclear Information System (INIS)

    Yamada, Masaaki; JI, Hantao; Gerhardt, Stefan P.; Belova, Elena V.; Davidson, Ronald C.; Mikkelsen, David R.

    2007-01-01

    A comprehensive research concept, known as SPIRIT, is described for the investigation of the formation, stability, and sustainment of oblate field reversed configurations (FRCs). This concept, whose name stands for Self-organized Plasma with Induction, Reconnection, and Injection Techniques (SPIRIT), allows for the study of FRC stability properties on time scales much longer than the energy confinement time. Counter-helicity merging of inductively formed spheromaks is utilized to form large-flux FRCs. These FRCs are sustained by neutral beam injection with the initial aid of compact ohmic solenoids. Stability to n=1 tilt/shift modes is provided by plasma shaping and conducting shells. Stability to n ≥ 2 co-interchange modes is achieved by a distribution of high-energy non-thermal ions provided by the neutral beam. The combination of plasma shaping, conducting shells, current sustainment, and the non-thermal beam component are expected to lead to a configuration with stability to all global MHD modes, a regime recently discovered through hybrid-MHD simulation using the HYM code. An experimental test of the concept, utilizing the existing Magnetic Reconnection Experiment (MRX) facility, is described. Initial experiments in MRX have confirmed the viability of the SPIRIT concept, and calculations indicate that the confinement of high-energy ions in MRX should be sufficient to test the SPIRIT concept. (author)

  4. Influence of test configuration on the combustion characteristics of polymers as ignition sources

    Science.gov (United States)

    Julien, Howard L.

    1993-01-01

    The experimental evaluation of polymers as ignition sources for metals was accomplished at the NASA White Sands Test Facility (WSTF) using a standard promoted combustion test. These tests involve the transient burning of materials in high-pressure oxygen environments. They have provided data from which design decisions can be made; data include video recordings of ignition and non-ignition for specific combinations of metals and polymers. Other tests provide the measured compositions of combustion products for polymers at select burn times and an empirical basis for estimating burn rates. With the current test configuration, the detailed analysis of test results requires modeling a three-dimensional, transient convection process involving fluid motion, thermal conduction and convection, the diffusion of chemical species, and the erosion of sample surface. At the high pressure extremes, it even requires the analysis of turbulent, transient convection where the physics of the problem are not well known and the computation requirements are not practical at this time. An alternative test configuration that can be analyzed with a relatively-simple convection model was developed during the summer period. The principal change constitutes replacing a large-diameter polymer disk at the end of the metal test rod with coaxial polymer cylinders that have a diameter nearer to that of the metal rod. The experimental objective is to assess the importance of test geometries on the promotion of metal ignition by testing with different lengths of the polymer and, with an extended effort, to analyze the surface combustion in the redesigned promoted combustion tests through analytical modeling of the process. The analysis shall use the results of cone-calorimeter tests of the polymer material to model primary chemical reactions and, with proper design of the promoted combustion test, modeling of the convection process could be conveniently limited to a quasi-steady boundary layer

  5. Effect of magnetic field gradient on power absorption in compact microwave plasma sources

    International Nuclear Information System (INIS)

    Dey, Indranuj; Shamim, Md.; Bhattacharjee, Sudeep

    2006-01-01

    We study the effect of the change in magnetic field gradient at the electron cyclotron resonance (ECR) point, on the generated plasma for two different cylindrical minimum B-field configurations, viz. the hexapole and the octupole. The plasma parameters such as the electron and ion density, electron temperature including the wave field characteristics (B-field and E-field) in the plasma will be measured and compared for the two configurations. (author)

  6. Design of a helicon plasma source for ion–ion plasma production

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, N., E-mail: narayan.sharma@cppipr.res.in; Chakraborty, M.; Neog, N.K.; Bandyopadhyay, M.

    2017-04-15

    Highlights: • Development of a helicon plasma system to carry out ion–ion plasma studies in electronegative gases such as Hydrogen, Oxygen and Chlorine. • Determination of initial parameters of helicon plasma source for ion–ion plasma by using dispersion relation of bounded helicon waves. • Design and development of solenoid with magnetic field strength production capability of ∼ 600 G along the axis of the chamber. • Optimization of the chamber parameters using Helic codes and estimation of optimum attainable density. • Estimation of RF power requirements for various gases. - Abstract: A helicon plasma system is being designed and developed at CPP-IPR. The design parameters of the system are deduced from the dispersion relation of bounded helicon waves and the required magnetic fields are simulated by using Poisson Superfish code. The Helic code is used to simulate the power deposition profile for various conditions and to investigate the optimum values of chamber parameters for effective coupling of radio frequency (RF) power to plasma. The helicon source system is aimed at carrying out ion–ion plasma studies in electronegative gases such as Hydrogen, Oxygen and Chlorine. The system mainly consists of a source chamber in which helicon plasma will be produced by injecting RF power at a frequency of 13.56 MHz through a right helical antenna in presence of a DC magnetic field followed by an expansion chamber in which it is expected to produce negative ions along with the positive ions. Installation of the various parts of the system is in progress. The details of the design and development of the system is presented in this article.

  7. Three-dimensional modeling of a negative ion source with a magnetic filter: impact of biasing the plasma electrode on the plasma asymmetry

    Science.gov (United States)

    Fubiani, G.; Boeuf, J. P.

    2015-10-01

    The effect on the plasma characteristics of biasing positively the plasma electrode (PE) in negative ion sources with a magnetic filter is analysed using a 3D particle-in-cell model with Monte-Carlo collisions (PIC-MCC). We specialize to the one driver (i.e. one inductively coupled radio-frequency discharge) BATMAN negative ion source and the 4-drivers (large volume) ELISE device. Both are ITER prototype high power tandem-type negative ion sources developed for the neutral beam injector (NBI) system. The plasma is generated in the driver and diffuses inside the second chamber which is magnetized. Asymmetric plasma profiles originate from the formation of an electric field transverse to the electron current flowing through the magnetic filter (Hall effect). The model shows that the importance of the asymmetry increases with the PE bias potential, i.e. with the electron flow from the driver to the extraction region and depends on the shape of the magnetic filter field. We find that although the plasma density and potential profiles may be more or less asymmetric depending on the filter field configuration, the electron current to the plasma grid is always strongly asymmetric.

  8. Three-dimensional modeling of a negative ion source with a magnetic filter: impact of biasing the plasma electrode on the plasma asymmetry

    International Nuclear Information System (INIS)

    Fubiani, G; Boeuf, J P

    2015-01-01

    The effect on the plasma characteristics of biasing positively the plasma electrode (PE) in negative ion sources with a magnetic filter is analysed using a 3D particle-in-cell model with Monte-Carlo collisions (PIC-MCC). We specialize to the one driver (i.e. one inductively coupled radio-frequency discharge) BATMAN negative ion source and the 4-drivers (large volume) ELISE device. Both are ITER prototype high power tandem-type negative ion sources developed for the neutral beam injector (NBI) system. The plasma is generated in the driver and diffuses inside the second chamber which is magnetized. Asymmetric plasma profiles originate from the formation of an electric field transverse to the electron current flowing through the magnetic filter (Hall effect). The model shows that the importance of the asymmetry increases with the PE bias potential, i.e. with the electron flow from the driver to the extraction region and depends on the shape of the magnetic filter field. We find that although the plasma density and potential profiles may be more or less asymmetric depending on the filter field configuration, the electron current to the plasma grid is always strongly asymmetric. (paper)

  9. ITER-FEAT magnetic configuration and plasma position/shape control in the nominal PF scenario

    International Nuclear Information System (INIS)

    Gribov, Y.V.; Albanese, R.; Ambrosino, G.

    2001-01-01

    The capability of the ITER-FEAT poloidal field system to support the four 'design' scenarios and the high current 'assessed' scenario have been studied. To operate with highly elongated plasma, the system has segmentation of the central solenoid and a separate fast feedback loop for plasma vertical stabilisation. Within the limits imposed on the coil currents, voltages and power, the poloidal field system provides the required plasma scenario and control capabilities. The separatrix deviation from the required position, in scenarios with minor disruptions is within less than about 100 mm. (author)

  10. Plasma shape control by pulsed solenoid on laser ion source

    International Nuclear Information System (INIS)

    Sekine, M.; Ikeda, S.; Romanelli, M.; Kumaki, M.; Fuwa, Y.; Kanesue, T.; Hayashizaki, N.; Lambiase, R.; Okamura, M.

    2015-01-01

    A Laser ion source (LIS) provides high current heavy ion beams with a very simple mechanical structure. Plasma is produced by a pulsed laser ablation of a solid state target and ions are extracted by an electric field. However, it was difficult to manipulate the beam parameters of a LIS, since the plasma condition could only be adjusted by the laser irradiation condition. To enhance flexibility of LIS operation, we employed a pulsed solenoid in the plasma drift section and investigated the effect of the solenoid field on singly charged iron beams. The experimentally obtained current profile was satisfactorily controlled by the pulsed magnetic field. This approach may also be useful to reduce beam emittance of a LIS

  11. Plasma shape control by pulsed solenoid on laser ion source

    Science.gov (United States)

    Sekine, M.; Ikeda, S.; Romanelli, M.; Kumaki, M.; Fuwa, Y.; Kanesue, T.; Hayashizaki, N.; Lambiase, R.; Okamura, M.

    2015-09-01

    A Laser ion source (LIS) provides high current heavy ion beams with a very simple mechanical structure. Plasma is produced by a pulsed laser ablation of a solid state target and ions are extracted by an electric field. However, it was difficult to manipulate the beam parameters of a LIS, since the plasma condition could only be adjusted by the laser irradiation condition. To enhance flexibility of LIS operation, we employed a pulsed solenoid in the plasma drift section and investigated the effect of the solenoid field on singly charged iron beams. The experimentally obtained current profile was satisfactorily controlled by the pulsed magnetic field. This approach may also be useful to reduce beam emittance of a LIS.

  12. Plasma shape control by pulsed solenoid on laser ion source

    Energy Technology Data Exchange (ETDEWEB)

    Sekine, M. [Tokyo Institute of Technology, Meguro-ku, Tokyo 2-12-1 (Japan); RIKEN, Wako, Saitama 351-0198 (Japan); Ikeda, S. [Tokyo Institute of Technology, Yokohama, Kanagawa 226-8502 (Japan); RIKEN, Wako, Saitama 351-0198 (Japan); Romanelli, M. [Cornell University, Ithaca, NY 14850 (United States); Kumaki, M. [RIKEN, Wako, Saitama 351-0198 (Japan); Waseda University, Shinjuku, Tokyo 169-0072 (Japan); Fuwa, Y. [RIKEN, Wako, Saitama 351-0198 (Japan); Kyoto University, Uji, Kyoto 611-0011 (Japan); Kanesue, T. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Hayashizaki, N. [Tokyo Institute of Technology, Meguro-ku, Tokyo 2-12-1 (Japan); Lambiase, R. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Okamura, M. [RIKEN, Wako, Saitama 351-0198 (Japan); Brookhaven National Laboratory, Upton, NY 11973 (United States)

    2015-09-21

    A Laser ion source (LIS) provides high current heavy ion beams with a very simple mechanical structure. Plasma is produced by a pulsed laser ablation of a solid state target and ions are extracted by an electric field. However, it was difficult to manipulate the beam parameters of a LIS, since the plasma condition could only be adjusted by the laser irradiation condition. To enhance flexibility of LIS operation, we employed a pulsed solenoid in the plasma drift section and investigated the effect of the solenoid field on singly charged iron beams. The experimentally obtained current profile was satisfactorily controlled by the pulsed magnetic field. This approach may also be useful to reduce beam emittance of a LIS.

  13. Plasma diagnostic tools for optimizing negative hydrogen ion sources

    International Nuclear Information System (INIS)

    Fantz, U.; Falter, H.D.; Franzen, P.; Speth, E.; Hemsworth, R.; Boilson, D.; Krylov, A.

    2006-01-01

    The powerful diagnostic tool of optical emission spectroscopy is used to measure the plasma parameters in negative hydrogen ion sources based on the surface mechanism. Results for electron temperature, electron density, atomic-to-molecular hydrogen density ratio, and gas temperature are presented for two types of sources, a rf source and an arc source, which are currently under development for a neutral beam heating system of ITER. The amount of cesium in the plasma volume is obtained from cesium radiation: the Cs neutral density is five to ten orders of magnitude lower than the hydrogen density and the Cs ion density is two to three orders of magnitude lower than the electron density in front of the grid. It is shown that monitoring of cesium lines is very useful for monitoring the cesium balance in the source. From a line-ratio method negative ion densities are determined. In a well-conditioned source the negative ion density is of the same order of magnitude as the electron density and correlates with extracted current densities

  14. Soft x-ray measurements in the FN-II dense plasma focus device for different anode configurations

    International Nuclear Information System (INIS)

    Rojo-Blanco, C; Castillo-Mejía, F; Rangel-Gutiérrez, J; Herrera-Velázquez, J J E

    2012-01-01

    A study of the soft x-ray emission is presented, for a low energy (4.8 kJ) dense plasma focus device. Three Quantrad Si PIN-diodes with differential filter combinations of Be, Al, Ti, Ni, and Mo are employed as time-resolved x-ray detectors. The x-ray flux in different energy windows is measured as function of the deuterium filling pressure. A comparison is made for three anode configurations: (a) hollow, (b) flat, and (c) 2mm diameter W needle.

  15. Dynamics of ion beam charge neutralization by ferroelectric plasma sources

    Energy Technology Data Exchange (ETDEWEB)

    Stepanov, Anton D.; Gilson, Erik P.; Grisham, Larry R.; Kaganovich, Igor D.; Davidson, Ronald C. [Princeton Plasma Physics Laboratory, Princeton University, P.O. Box 451, Princeton, New Jersey 08543 (United States)

    2016-04-15

    Ferroelectric Plasma Sources (FEPSs) can generate plasma that provides effective space-charge neutralization of intense high-perveance ion beams, as has been demonstrated on the Neutralized Drift Compression Experiment NDCX-I and NDCX-II. This article presents experimental results on charge neutralization of a high-perveance 38 keV Ar{sup +} beam by a plasma produced in a FEPS discharge. By comparing the measured beam radius with the envelope model for space-charge expansion, it is shown that a charge neutralization fraction of 98% is attainable with sufficiently dense FEPS plasma. The transverse electrostatic potential of the ion beam is reduced from 15 V before neutralization to 0.3 V, implying that the energy of the neutralizing electrons is below 0.3 eV. Measurements of the time-evolution of beam radius show that near-complete charge neutralization is established ∼5 μs after the driving pulse is applied to the FEPS and can last for 35 μs. It is argued that the duration of neutralization is much longer than a reasonable lifetime of the plasma produced in the sub-μs surface discharge. Measurements of current flow in the driving circuit of the FEPS show the existence of electron emission into vacuum, which lasts for tens of μs after the high voltage pulse is applied. It is argued that the beam is neutralized by the plasma produced by this process and not by a surface discharge plasma that is produced at the instant the high-voltage pulse is applied.

  16. Laboratory Plasma Source as an MHD Model for Astrophysical Jets

    Science.gov (United States)

    Mayo, Robert M.

    1997-01-01

    The significance of the work described herein lies in the demonstration of Magnetized Coaxial Plasma Gun (MCG) devices like CPS-1 to produce energetic laboratory magneto-flows with embedded magnetic fields that can be used as a simulation tool to study flow interaction dynamic of jet flows, to demonstrate the magnetic acceleration and collimation of flows with primarily toroidal fields, and study cross field transport in turbulent accreting flows. Since plasma produced in MCG devices have magnetic topology and MHD flow regime similarity to stellar and extragalactic jets, we expect that careful investigation of these flows in the laboratory will reveal fundamental physical mechanisms influencing astrophysical flows. Discussion in the next section (sec.2) focuses on recent results describing collimation, leading flow surface interaction layers, and turbulent accretion. The primary objectives for a new three year effort would involve the development and deployment of novel electrostatic, magnetic, and visible plasma diagnostic techniques to measure plasma and flow parameters of the CPS-1 device in the flow chamber downstream of the plasma source to study, (1) mass ejection, morphology, and collimation and stability of energetic outflows, (2) the effects of external magnetization on collimation and stability, (3) the interaction of such flows with background neutral gas, the generation of visible emission in such interaction, and effect of neutral clouds on jet flow dynamics, and (4) the cross magnetic field transport of turbulent accreting flows. The applicability of existing laboratory plasma facilities to the study of stellar and extragalactic plasma should be exploited to elucidate underlying physical mechanisms that cannot be ascertained though astrophysical observation, and provide baseline to a wide variety of proposed models, MHD and otherwise. The work proposed herin represents a continued effort on a novel approach in relating laboratory experiments to

  17. Deposition Rate and Energy Enhancements of TiN Thin-Film in a Magnetized Sheet Plasma Source

    OpenAIRE

    Hamdi Muhyuddin D. Barra; Henry J. Ramos

    2011-01-01

    Titanium nitride (TiN) has been synthesized using the sheet plasma negative ion source (SPNIS). The parameters used for its effective synthesis has been determined from previous experiments and studies. In this study, further enhancement of the deposition rate of TiN synthesis and advancement of the SPNIS operation is presented. This is primarily achieved by the addition of Sm-Co permanent magnets and a modification of the configuration in the TiN deposition process. The ...

  18. High Current, High Density Arc Plasma as a New Source for WiPAL

    Science.gov (United States)

    Waleffe, Roger; Endrizzi, Doug; Myers, Rachel; Wallace, John; Clark, Mike; Forest, Cary; WiPAL Team

    2016-10-01

    The Wisconsin Plasma Astrophysics Lab (WiPAL) has installed a new array of nineteen plasma sources (plasma guns) on its 3 m diameter, spherical vacuum vessel. Each gun is a cylindrical, molybdenum, washer-stabilized, arc plasma source. During discharge, the guns are maintained at 1.2 kA across 100 V for 10 ms by the gun power supply establishing a high density plasma. Each plasma source is fired independently allowing for adjustable plasma parameters, with densities varying between 1018 -1019 m-3 and electron temperatures of 5-15 eV. Measurements were characterized using a 16 tip Langmuir probe. The plasma source will be used as a background plasma for the magnetized coaxial plasma gun (MCPG), the Terrestrial Reconnection Experiment (TREX), and as the plasma source for a magnetic mirror experiment. Temperature, density, and confinement results will be presented. This work is supported by the DoE and the NSF.

  19. Mass analyzer ``MASHA'' high temperature target and plasma ion source

    Science.gov (United States)

    Semchenkov, A. G.; Rassadov, D. N.; Bekhterev, V. V.; Bystrov, V. A.; Chizov, A. Yu.; Dmitriev, S. N.; Efremov, A. A.; Guljaev, A. V.; Kozulin, E. M.; Oganessian, Yu. Ts.; Starodub, G. Ya.; Voskresensky, V. M.; Bogomolov, S. L.; Paschenko, S. V.; Zelenak, A.; Tikhonov, V. I.

    2004-05-01

    A new separator and mass analyzer of super heavy atoms (MASHA) has been created at the FLNR JINR Dubna to separate and measure masses of nuclei and molecules with precision better than 10-3. First experiments with the FEBIAD plasma ion source have been done and give an efficiency of ionization of up to 20% for Kr with a low flow test leak (6 particle μA). We suppose a magnetic field optimization, using the additional electrode (einzel lens type) in the extracting system, and an improving of the vacuum conditions in order to increase the ion source efficiency.

  20. Mass analyzer 'MASHA' high temperature target and plasma ion source

    International Nuclear Information System (INIS)

    Semchenkov, A.G.; Rassadov, D.N.; Bekhterev, V.V.; Bystrov, V.A.; Chizov, A.Yu.; Dmitriev, S.N.; Efremov, A.A.; Guljaev, A.V.; Kozulin, E.M.; Oganessian, Yu.Ts.; Starodub, G.Ya.; Voskresensky, V.M.; Bogomolov, S.L.; Paschenko, S.V.; Zelenak, A.; Tikhonov, V.I.

    2004-01-01

    A new separator and mass analyzer of super heavy atoms (MASHA) has been created at the FLNR JINR Dubna to separate and measure masses of nuclei and molecules with precision better than 10 -3 . First experiments with the FEBIAD plasma ion source have been done and give an efficiency of ionization of up to 20% for Kr with a low flow test leak (6 particle μA). We suppose a magnetic field optimization, using the additional electrode (einzel lens type) in the extracting system, and an improving of the vacuum conditions in order to increase the ion source efficiency

  1. Efficient cesiation in RF driven surface plasma negative ion source

    Energy Technology Data Exchange (ETDEWEB)

    Belchenko, Yu.; Ivanov, A.; Konstantinov, S.; Sanin, A., E-mail: sanin@inp.nsk.su; Sotnikov, O. [Budker Institute of Nuclear Physics, Siberian Branch of Russian Academy of Sciences, Novosibirsk (Russian Federation)

    2016-02-15

    Experiments on hydrogen negative ions production in the large radio-frequency negative ion source with cesium seed are described. The system of directed cesium deposition to the plasma grid periphery was used. The small cesium seed (∼0.5 G) provides an enhanced H{sup −} production during a 2 month long experimental cycle. The gradual increase of negative ion yield during the long-term source runs was observed after cesium addition to the source. The degraded H{sup −} production was recorded after air filling to the source or after the cesium washing away from the driver and plasma chamber walls. The following source conditioning by beam shots produces the gradual recovery of H{sup −} yield to the high value. The effect of H{sup −} yield recovery after cesium coverage passivation by air fill was studied. The concept of cesium coverage replenishment and of H{sup −} yield recovery due to sputtering of cesium from the deteriorated layers is discussed.

  2. Development of a magnetized coaxial plasma gun for compact toroid injection into the C-2 field-reversed configuration device

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, T., E-mail: cstd14003@g.nihon-u.ac.jp; Sekiguchi, J.; Asai, T. [College of Science and Technology, Nihon University, 1-8-14 Kanda, Chiyoda-ku, Tokyo 1018308 (Japan); Gota, H.; Garate, E.; Allfrey, I.; Valentine, T.; Morehouse, M.; Roche, T.; Kinley, J.; Aefsky, S.; Cordero, M.; Waggoner, W.; Binderbauer, M. [Tri Alpha Energy, Inc., P.O. Box 7010 Rancho Santa Margarita, California 92688 (United States); Tajima, T. [Tri Alpha Energy, Inc., P.O. Box 7010 Rancho Santa Margarita, California 92688 (United States); Department of Physics and Astronomy, University of California, Irvine, California 92697 (United States)

    2016-05-15

    A compact toroid (CT) injector was developed for the C-2 device, primarily for refueling of field-reversed configurations. The CTs are formed by a magnetized coaxial plasma gun (MCPG), which consists of coaxial cylindrical electrodes and a bias coil for creating a magnetic field. First, a plasma ring is generated by a discharge between the electrodes and is accelerated by Lorenz self-force. Then, the plasma ring is captured by an interlinkage flux (poloidal flux). Finally, the fully formed CT is ejected from the MCPG. The MCPG described herein has two gas injection ports that are arranged tangentially on the outer electrode. A tungsten-coated inner electrode has a head which can be replaced with a longer one to extend the length of the acceleration region for the CT. The developed MCPG has achieved supersonic CT velocities of ∼100 km/s. Plasma parameters for electron density, electron temperature, and the number of particles are ∼5 × 10{sup 21} m{sup −3}, ∼40 eV, and 0.5–1.0 × 10{sup 19}, respectively.

  3. Development of a magnetized coaxial plasma gun for compact toroid injection into the C-2 field-reversed configuration device.

    Science.gov (United States)

    Matsumoto, T; Sekiguchi, J; Asai, T; Gota, H; Garate, E; Allfrey, I; Valentine, T; Morehouse, M; Roche, T; Kinley, J; Aefsky, S; Cordero, M; Waggoner, W; Binderbauer, M; Tajima, T

    2016-05-01

    A compact toroid (CT) injector was developed for the C-2 device, primarily for refueling of field-reversed configurations. The CTs are formed by a magnetized coaxial plasma gun (MCPG), which consists of coaxial cylindrical electrodes and a bias coil for creating a magnetic field. First, a plasma ring is generated by a discharge between the electrodes and is accelerated by Lorenz self-force. Then, the plasma ring is captured by an interlinkage flux (poloidal flux). Finally, the fully formed CT is ejected from the MCPG. The MCPG described herein has two gas injection ports that are arranged tangentially on the outer electrode. A tungsten-coated inner electrode has a head which can be replaced with a longer one to extend the length of the acceleration region for the CT. The developed MCPG has achieved supersonic CT velocities of ∼100 km/s. Plasma parameters for electron density, electron temperature, and the number of particles are ∼5 × 10(21) m(-3), ∼40 eV, and 0.5-1.0 × 10(19), respectively.

  4. Development of a magnetized coaxial plasma gun for compact toroid injection into the C-2 field-reversed configuration device

    International Nuclear Information System (INIS)

    Matsumoto, T.; Sekiguchi, J.; Asai, T.; Gota, H.; Garate, E.; Allfrey, I.; Valentine, T.; Morehouse, M.; Roche, T.; Kinley, J.; Aefsky, S.; Cordero, M.; Waggoner, W.; Binderbauer, M.; Tajima, T.

    2016-01-01

    A compact toroid (CT) injector was developed for the C-2 device, primarily for refueling of field-reversed configurations. The CTs are formed by a magnetized coaxial plasma gun (MCPG), which consists of coaxial cylindrical electrodes and a bias coil for creating a magnetic field. First, a plasma ring is generated by a discharge between the electrodes and is accelerated by Lorenz self-force. Then, the plasma ring is captured by an interlinkage flux (poloidal flux). Finally, the fully formed CT is ejected from the MCPG. The MCPG described herein has two gas injection ports that are arranged tangentially on the outer electrode. A tungsten-coated inner electrode has a head which can be replaced with a longer one to extend the length of the acceleration region for the CT. The developed MCPG has achieved supersonic CT velocities of ∼100 km/s. Plasma parameters for electron density, electron temperature, and the number of particles are ∼5 × 10"2"1 m"−"3, ∼40 eV, and 0.5–1.0 × 10"1"9, respectively.

  5. Behavior of a plasma in a high-density gas-embedded Z-pinch configuration

    International Nuclear Information System (INIS)

    Shlachter, J.S.

    1982-05-01

    The theoretical analysis of a high density Z-pinch (HDZP) begins with an examination of the steady state energy balance between ohmic heating and bremsstrahlung radiation losses for a plasma column in pressure equilibrium. The model is then expanded to include the time-varying internal energy and results in a quasi-equilibrium prescription for the load current through a constant radius plasma channel. This set of current waveforms is useful in the design of experimental systems. The behavior of a plasma for physically realizable conditions is first examined by allowing adiabatic changes in the column radius. A more complete model is then developed by incorporating inertial effects into the momentum equation, and the resultant global MHD computational model is compared with more sophisticated, and costly, one- and two-dimensional computer simulations. These comparisons demonstrate the advantages of the global MHD description over previously developed zero-dimensional models

  6. Regimes of pulsed formation of a compact plasma configuration with a high energy input

    Energy Technology Data Exchange (ETDEWEB)

    Romadanov, I. V.; Ryzhkov, S. V., E-mail: svryzhkov@bmstu.ru [Bauman Moscow State Technical University (Russian Federation)

    2015-10-15

    Results of experiments on the formation of a compact toroidal magnetic configuration at the Compact Toroid Challenge setup are presented. The experiments were primarily aimed at studying particular formation stages. Two series of experiments, with and without an auxiliary capacitor bank, were conducted. The magnetic field was measured, its time evolution and spatial distribution over the chamber volume were determined, and its influence on the formation regimes was investigated.

  7. Fast plasma discharge capillary design as a high power throughput soft x-ray emission source.

    Science.gov (United States)

    Wyndham, E S; Favre, M; Valdivia, M P; Valenzuela, J C; Chuaqui, H; Bhuyan, H

    2010-09-01

    We present the experimental details and results from a low energy but high repetition rate compact plasma capillary source for extreme ultraviolet and soft x-ray research and applications. Two lengths of capillary are mounted in two versions of a closely related design. The discharge operates in 1.6 and 3.2 mm inner diameter alumina capillaries of lengths 21 and 36 mm. The use of water both as dielectric and as coolant simplifies the compact low inductance design with nanosecond discharge periods. The stored electrical energy of the discharge is approximately 0.5 J and is provided by directly charging the capacitor plates from an inexpensive insulated-gate bipolar transistor in 1 μs or less. We present characteristic argon spectra from plasma between 30 and 300 Å as well as temporally resolved x-ray energy fluence in discrete bands on axis. The spectra also allow the level of ablated wall material to be gauged and associated with useful capillary lifetime according to the chosen configuration and energy storage. The connection between the electron beams associated with the transient hollow cathode mechanism, soft x-ray output, capillary geometry, and capillary lifetime is reported. The role of these e-beams and the plasma as measured on-axis is discussed. The relation of the electron temperature and the ionization stages observed is discussed in the context of some model results of ionization in a non-Maxwellian plasma.

  8. Spectroscopic and shadowgraphic analysis of laser induced plasmas in the orthogonal double pulse pre-ablation configuration

    International Nuclear Information System (INIS)

    Cristoforetti, G.; Legnaioli, S.; Pardini, L.; Palleschi, V.; Salvetti, A.; Tognoni, E.

    2006-01-01

    This work focuses on the study of the plumes obtained in the double pulse orthogonal Laser Induced Breakdown Spectroscopy (LIBS) in the pre-ablation configuration using both spectroscopic and shadowgraphic approaches. Single and double pulse LIBS experiments were carried out on a brass sample in air. Both the distance of the air plasma from the target surface and the interpulse delay were varied (respectively in the range 0.1-4.2 mm and up to 50 μs) revealing a significant variation of the plasma emission and of the plume-shock wave dynamical expansion in different cases. The intensity of both atomic and ionized zinc lines was measured in all the cases, allowing the calculation of the spatially averaged temperature and electron density and an estimation of the ablated mass. The line intensities and the thermodynamic parameters obtained by the spectroscopic measurements were discussed bearing in mind the dynamical expansion characteristics obtained from the shadowgraphic approach. All the data seem to be consistent with the model previously proposed for the double pulse collinear configuration where the line enhancement is mainly attributed to the ambient gas rarefaction produced by the first laser pulse, which causes a less effective shielding of the second laser pulse

  9. Conceptual design of a permanent ring magnet based helicon plasma source module intended to be used in a large size fusion grade ion source

    Energy Technology Data Exchange (ETDEWEB)

    Pandey, Arun; Sudhir, Dass; Bandyopadhyay, M., E-mail: mainak@iter-india.org; Chakraborty, A.

    2016-02-15

    A conceptual design of a permanent magnet based single driver helicon plasma source module along with its design approach is described in this paper. The module unit is intended to be used in a large size ion source. The conceptual design of the helicon source module has been carried out using a computer code, HELIC. The magnetic field topology for the ring magnet is simulated with another code, BFieldM and the magnetic field values obtained from the calculation are further used as input in HELIC calculation for the conceptual design. The module is conceptualized based on a cylindrical glass vessel to produce plasma of diameter ∼50 mm, height ∼50 mm. The inner diameter of the permanent ring magnets is also of the same dimension with thickness ∼10 mm each, placed slightly above the backplate to maintain the required magnetic field. The simulated results show that for hydrogen gas, expected plasma density can be achieved as high as ∼10{sup 12}–10{sup 13} cm{sup −3} in the proposed helicon source configuration using 1 kW 13.56 MHz RF generator. An experimental setup to characterize a Helicon source module unit, consisting of a cylindrical glass (plasma) chamber along with the vacuum system, RF power supplies, probes and data acquisition system is being installed.

  10. PWFA plasma source - interferometric diagnostics for Li vapor density measurements

    International Nuclear Information System (INIS)

    Sivakumaran, V.; Mohandas, K.K.; Singh, Sneha; Ravi Kumar, A.V.

    2015-01-01

    A prototype (40 cm long) plasma source based on Li heat pipe oven has been developed for the Plasma Wakefield Acceleration (PWFA) experiments at IPR (IPR), Gujarat as a part of the ongoing Accelerator Programme. Li vapor in the oven is produced by heating solid Li in helium buffer gas. A uniform column of Li plasma is generated by UV photo ionization (193 nm) of the Li vapor in the heat pipe oven. In these experiments, an accurate measurement of Li vapor density is important as it has got a direct consequence on the plasma electron density. In the present experiment, the vapor density is measured optically by using Hook method (spectrally resolved white light interferometry). The hook like structure formed near the vicinity of the Li 670.8 nm resonance line was recorded with a white light Mach Zehnder interferometer crossed with an imaging spectrograph to estimate the Li vapor density. The vapor density measurements have been carried out as a function of external oven temperature and the He buffer gas pressure. This technique has the advantage of being insensitive to line broadening and line shape, and its high dynamic range even with optically thick absorption line. Here, we present the line integrated Lithium vapor density measurement using Hook method and also compare the same with other optical diagnostic techniques (White light absorption and UV absorption) for Li vapor density measurements. (author)

  11. Preliminary Calculation for Plasma Chamber Design of Pulsed Electron Source Based on Plasma

    International Nuclear Information System (INIS)

    Widdi Usada

    2009-01-01

    This paper described the characteristics of pulsed electron sources with anode-cathode distance of 5 cm, electrode diameter of 10 cm, driven by capacitor energy of 25 J. The preliminary results showed that if the system is operated with diode resistance is 1.6 Ω, plasma resistance is 0.14 Ω, and β is 0.94, the achieved of plasma voltage is 640 V, its current is 4.395 kA with its pulse width of 0.8 μsecond. According to breakdown voltage based on Paschen empirical formula, with this achieved voltage, this system could be operated for operation pressure of 1 torr. (author)

  12. Modeling of magnetically enhanced capacitively coupled plasma sources: Ar discharges

    International Nuclear Information System (INIS)

    Kushner, Mark J.

    2003-01-01

    Magnetically enhanced capacitively coupled plasma sources use transverse static magnetic fields to modify the performance of low pressure radio frequency discharges. Magnetically enhanced reactive ion etching (MERIE) sources typically use magnetic fields of tens to hundreds of Gauss parallel to the substrate to increase the plasma density at a given pressure or to lower the operating pressure. In this article results from a two-dimensional hybrid-fluid computational investigation of MERIE reactors with plasmas sustained in argon are discussed for an industrially relevant geometry. The reduction in electron cross field mobility as the magnetic field increases produces a systematic decrease in the dc bias (becoming more positive). This decrease is accompanied by a decrease in the energy and increase in angular spread of the ion flux to the substrate. Similar trends are observed when decreasing pressure for a constant magnetic field. Although for constant power the magnitudes of ion fluxes to the substrate increase with moderate magnetic fields, the fluxes decreased at larger magnetic fields. These trends are due, in part, to a reduction in the contributions of more efficient multistep ionization

  13. New developments in metal ion implantation by vacuum arc ion sources and metal plasma immersion

    International Nuclear Information System (INIS)

    Brown, I.G.; Anders, A.; Anders, S.

    1996-01-01

    Ion implantation by intense beams of metal ions can be accomplished using the dense metal plasma formed in a vacuum arc discharge embodied either in a vacuum arc ion source or in a metal plasma immersion configuration. In the former case high energy metal ion beams are formed and implantation is done in a more-or-less conventional way, and in the latter case the substrate is immersed in the plasma and repetitively pulse-biased so as to accelerate the ions at the high voltage plasma sheath formed at the substrate. A number of advances have been made in the last few years, both in plasma technology and in the surface modification procedures, that enhance the effectiveness and versatility of the methods, including for example: controlled increase of the in charge states produced; operation in a dual metal-gaseous ion species mode; very large area beam formation; macroparticle filtering; and the development of processing regimes for optimizing adhesion, morphology and structure. These complementary ion processing techniques provide the plasma tools for doing ion surface modification over a very wide parameter regime, from pure ion implantation at energies approaching the MeV level, through ion mixing at energies in the ∼1 to ∼100 keV range, to IBAD-like processing at energies from a few tens of eV to a few keV. Here the authors review the methods, describe a number of recent developments, and outline some of the surface modification applications to which the methods have been put. 54 refs., 9 figs

  14. A compact and continuously driven supersonic plasma and neutral source

    Energy Technology Data Exchange (ETDEWEB)

    Asai, T.; Itagaki, H.; Numasawa, H.; Terashima, Y.; Hirano, Y. [Department of Physics, College of Science and Technology, Nihon University, Tokyo 101-8308 (Japan); Hirose, A. [Plasma Physics Laboratory, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E2 (Canada)

    2010-10-15

    A compact and repetitively driven plasma source has been developed by utilizing a magnetized coaxial plasma gun (MCPG) for diagnostics requiring deep penetration of a large amount of neutral flux. The system consists of a MCPG 95mm in length with a DN16 ConFlat connection port and an insulated gate bipolar transistor (IGBT) inverter power unit. The power supply consists of an array of eight IGBT units and is able to switch the discharge on and off at up to 10 kV and 600 A with a maximum repetitive frequency of 10 kHz. Multiple short duration discharge pulses maximize acceleration efficiency of the plasmoid. In the case of a 10 kHz operating frequency, helium-plasmoids in the velocity range of 20 km/s can be achieved.

  15. A compact and continuously driven supersonic plasma and neutral source.

    Science.gov (United States)

    Asai, T; Itagaki, H; Numasawa, H; Terashima, Y; Hirano, Y; Hirose, A

    2010-10-01

    A compact and repetitively driven plasma source has been developed by utilizing a magnetized coaxial plasma gun (MCPG) for diagnostics requiring deep penetration of a large amount of neutral flux. The system consists of a MCPG 95mm in length with a DN16 ConFlat connection port and an insulated gate bipolar transistor (IGBT) inverter power unit. The power supply consists of an array of eight IGBT units and is able to switch the discharge on and off at up to 10 kV and 600 A with a maximum repetitive frequency of 10 kHz. Multiple short duration discharge pulses maximize acceleration efficiency of the plasmoid. In the case of a 10 kHz operating frequency, helium-plasmoids in the velocity range of 20 km/s can be achieved.

  16. A Planar Source of Atmospheric-Pressure Plasma Jet

    Science.gov (United States)

    Zhdanova, O. S.; Kuznetsov, V. S.; Panarin, V. A.; Skakun, V. S.; Sosnin, E. A.; Tarasenko, V. F.

    2018-01-01

    In a single-barrier discharge with voltage sharpening and low gas consumption (up to 1 L/min), plane atmospheric pressure plasma jets with a width of up to 3 cm and length of up to 4 cm in air are formed in the slit geometry of the discharge zone. The energy, temperature, and spectral characteristics of the obtained jets have been measured. The radiation spectrum contains intense maxima corresponding to vibrational transitions of the second positive system of molecular nitrogen N2 ( C 3Π u → B 3Π g ) and comparatively weak transition lines of the first positive system of the N 2 + ion ( B 2Σ u + → X 2Σ g ). By an example of inactivation of the Staphylococcus aureus culture (strain ATCC 209), it is shown that plasma is a source of chemically active particles providing the inactivation of microorganisms.

  17. Soft x-ray source by laser produced Xe plasma

    International Nuclear Information System (INIS)

    Amano, Sho; Masuda, Kazuya; Miyamoto, Shuji; Mochizuki, Takayasu

    2010-01-01

    The laser plasma soft X-ray source in the wavelength rage of 5-17 nm was developed, which consisted of the rotating drum system supplying cryogenic Xe target and the high repetition rate pulse Nd:YAG slab laser. We found the maximum conversion efficiency of 30% and it demonstrated the soft X-ray generation with the high repetition rate pulse of 320 pps and the high average power of 20 W. The soft X-ray cylindrical mirror was developed and successfully focused the soft X-ray with an energy intensity of 1.3 mJ/cm 2 . We also succeeded in the plasma debris mitigation with Ar gas. This will allow a long lifetime of the mirror and a focusing power intensity of 400 mW/cm 2 with 320 pps. The high power soft X-ray is useful for various applications. (author)

  18. Modelling RF-plasma interaction in ECR ion sources

    Directory of Open Access Journals (Sweden)

    Mascali David

    2017-01-01

    Full Text Available This paper describes three-dimensional self-consistent numerical simulations of wave propagation in magnetoplasmas of Electron cyclotron resonance ion sources (ECRIS. Numerical results can give useful information on the distribution of the absorbed RF power and/or efficiency of RF heating, especially in the case of alternative schemes such as mode-conversion based heating scenarios. Ray-tracing approximation is allowed only for small wavelength compared to the system scale lengths: as a consequence, full-wave solutions of Maxwell-Vlasov equation must be taken into account in compact and strongly inhomogeneous ECRIS plasmas. This contribution presents a multi-scale temporal domains approach for simultaneously including RF dynamics and plasma kinetics in a “cold-plasma”, and some perspectives for “hot-plasma” implementation. The presented results rely with the attempt to establish a modal-conversion scenario of OXB-type in double frequency heating inside an ECRIS testbench.

  19. Improvement of a microwave ECR plasma source for the plasma immersion ion implantation and deposition process

    International Nuclear Information System (INIS)

    Wu Hongchen; Zhang Huafang; Peng Liping; Jiang Yanli; Ma Guojia

    2004-01-01

    The Plasma Immersion Ion Implantation and Deposition (PIII and D) process has many advantages over the pure plasma immersion ion implantation or deposition. It can compensate for or eliminate the disadvantages of the shallow modification layer (for PIII) and increase the bond strength of the coating (of deposition). For this purpose, a new type of microwave plasma source used in the PIII and D process was developed, composed of a vacuum bend wave guide and a special magnetic circuit, so that the coupling window was protected from being deposited with a coating and bombarded by high-energy particles. So the life of the window is increased. To enhance the bonding between the coating and substrate a new biasing voltage is applied to the work piece so that the implantation and deposition (or hybrid process) can be completed in one vacuum cycle

  20. Production of accelerated electrons near an electron source in the plasma resonance region

    International Nuclear Information System (INIS)

    Fedorov, V.A.

    1989-01-01

    Conditions of generation of plasma electrons accelerated and their characteristics in the vicinity of an electron source are determined. The electron source isolated electrically with infinitely conducting surface, being in unrestricted collisionless plasma ω 0 >>ν, where ω 0 - plasma frequency of nonperturbated plasma, ν - frequency of plasma electron collisions with other plasma particles, is considered. Spherically symmetric injection of electrons, which rates are simulated by ω frequency, occurs from the source surface. When describing phenomena in the vicinity of the electron source, one proceeds from the quasihydrodynamic equation set

  1. Plasma devices for hydrocarbon reformation

    KAUST Repository

    Cha, Min

    2017-01-01

    Plasma devices for hydrocarbon reformation are provided. Methods of using the devices for hydrocarbon reformation are also provided. The devices can include a liquid container to receive a hydrocarbon source, and a plasma torch configured

  2. Magnetic insulation of secondary electrons in plasma source ion implantation

    International Nuclear Information System (INIS)

    Rej, D.J.; Wood, B.P.; Faehl, R.J.; Fleischmann, H.H.

    1993-01-01

    The uncontrolled loss of accelerated secondary electrons in plasma source ion implantation (PSII) can significantly reduce system efficiency and poses a potential x-ray hazard. This loss might be reduced by a magnetic field applied near the workpiece. The concept of magnetically-insulated PSII is proposed, in which secondary electrons are trapped to form a virtual cathode layer near the workpiece surface where the local electric field is essentially eliminated. Subsequent electrons that are emitted can then be reabsorbed by the workpiece. Estimates of anomalous electron transport from microinstabilities are made. Insight into the process is gained with multi-dimensional particle-in-cell simulations

  3. One-dimensional modeling of plasma diffusion in field reversed configurations

    International Nuclear Information System (INIS)

    Hamasaki, S.; Krall, N.A.

    1986-03-01

    Over the past several years, a picture has emerged of transport in field reversed configuration (FRC) which explains many, though not all, of the loss phenomena observed in that device. That picture is complicated by the geometry, which includes both magnetically connected and magnetically isolated regions, and by the transport process, which includes a substantial contribution from short wavelength, fast time scale processes. This paper extends our previous work on this topic by carrying a one-dimensional model as far as it can be carried, in terms of goemetrical and physical consistency, and isolates the difference between the model and experiment as coming from phenomena beyond the scope of 1-D anomalous transport

  4. Energy efficiency of the CTX magnetized coaxial plasma source

    International Nuclear Information System (INIS)

    Fernandez, J.C.; Barnes, C.W.; Jarboe, T.R.; Knox, S.O.; Platts, D.A.; McKenna, K.F.

    1985-01-01

    The energy efficiency of the CTX coaxial plasma source in creating spheromaks is determined experimentally to be in agreement with the theoretical prediction of lambda/sub sp//lambda/sub g/, where del x B = lambda/sub sp/ B in the spheromak, and lambda/sub g/ identical with μ 0 I/sub g//phi/sub g/ with I/sub g/ the source current and phi/sub g/ the magnetic flux through either source electrode. This is shown to be equivalent to magnetic helicity conservation. The spheromak impurity radiation was measured using an absolutely calibrated single chord bolometer system. The theoretical efficiency is within the experimental uncertainty of the ratio of spheromak radiated energy to source input energy in a group of ''dirty'' discharges. But the radiation measurement uncertainty is too large to determine whether a substantial part of the excess source energy not used in the production of spheromak magnetic energy is radiated from the spheromak volume

  5. Estimation of Neutral Density in Edge Plasma with Double Null Configuration in EAST

    International Nuclear Information System (INIS)

    Zhang Ling; Xu Guosheng; Ding Siye; Gao Wei; Wu Zhenwei; Chen Yingjie; Huang Juan; Liu Xiaoju; Zang Qing; Chang Jiafeng; Zhang Wei; Li Yingying; Qian Jinping

    2011-01-01

    In this work, population coefficients of hydrogen's n = 3 excited state from the hydrogen collisional-radiative (CR) model, from the data file of DEGAS 2, are used to calculate the photon emissivity coefficients (PECs) of hydrogen Balmer-α (n = 3 → n = 2) (H α ). The results are compared with the PECs from Atomic Data and Analysis Structure (ADAS) database, and a good agreement is found. A magnetic surface-averaged neutral density profile of typical double-null (DN) plasma in EAST is obtained by using FRANTIC, the 1.5-D fluid transport code. It is found that the sum of integral D α and H α emission intensity calculated via the neutral density agrees with the measured results obtained by using the absolutely calibrated multi-channel poloidal photodiode array systems viewing the lower divertor at the last closed flux surface (LCFS). It is revealed that the typical magnetic surface-averaged neutral density at LCFS is about 3.5 x 10 16 m -3 . (magnetically confined plasma)

  6. Characterization of a gamma-ray source based on a laser-plasma accelerator with applications to radiography

    International Nuclear Information System (INIS)

    Edwards, R.D.; Sinclair, M.A.; Goldsack, T.J.; Krushelnick, K.; Beg, F.N.; Clark, E.L.; Dangor, A.E.; Najmudin, Z.; Tatarakis, M.; Walton, B.; Zepf, M.; Ledingham, K.W.D.; Spencer, I.; Norreys, P.A.; Clarke, R.J.; Kodama, R.; Toyama, Y.; Tampo, M.

    2002-01-01

    The application of high intensity laser-produced gamma rays is discussed with regard to picosecond resolution deep-penetration radiography. The spectrum and angular distribution of these gamma rays is measured using an array of thermoluminescent detectors for both an underdense (gas) target and an overdense (solid) target. It is found that the use of an underdense target in a laser plasma accelerator configuration produces a much more intense and directional source. The peak dose is also increased significantly. Radiography is demonstrated in these experiments and the source size is also estimated

  7. Optimal pulse modulator design criteria for plasma source ion implanters

    International Nuclear Information System (INIS)

    Reass, W.

    1993-01-01

    This paper describes what are believed to be the required characteristics of a high-voltage modulator for efficient and optimal ion deposition from the ''Plasma Source Ion Implantation'' (PSII) process. The PSII process is a method to chemically or physically alter and enhance surface properties of objects by placing them in a weakly ionized plasma and pulsing the object with a high negative voltage. The attracted ions implant themselves and form chemical bonds or are interstitially mixed with the base material. Present industrial uses of implanted objects tends to be for limited-production, high-value-added items. Traditional implanting hardware uses the typical low-current (ma) semiconductor ''raster scan'' implanters. The targets must also be manipulated to maintain a surface normal to the ion beam. The PSII method can provide ''bulk'' equipment processing on a large industrial scale. For the first generation equipment, currents are scaled from milliamps to hundreds of amps, voltages to -175kV, at kilohertz rep-rates, and high plasma ion densities

  8. Honeycomb surface-plasma negative-ion source

    International Nuclear Information System (INIS)

    Bel'chenko, Yu.I.

    1983-01-01

    A honeycomb surface-plasma source (SPS) of negative hydrogen ions the cathode of which consists of a great number of cells with spherical-concave surfaces, is described. Negative ions, knocked off the cathode by cesium-hydrogen discharge fast particles are accelerated in the near-cathode potential drop layer and focused geometrically on small emission apertures in the anode. Due to this, the gas and energy efficiency of the source is increased and the power density on the cathode is decreased. The H - yield is proportional to the number of celts. A pulse beam of negative ions with current up to 4 A is obtained and accelerated to 25 kV from the cathode effective area of 10.6 cm 2 through emission ports of 0.5 cm 2 total area. The honeycomb SPSs with a greater number of cells are promising as regards obtaining negative ion-beams with the current of scores of amperes

  9. Development of neutral beam source using electron beam excited plasma

    International Nuclear Information System (INIS)

    Hara, Yasuhiro; Hamagaki, Manabu; Mise, Takaya; Hara, Tamio

    2011-01-01

    A low-energy neutral beam (NB) source, which consists of an electron-beam-excited plasma (EBEP) source and two carbon electrodes, has been developed for damageless etching of ultra-large-scale integrated (ULSI) devices. It has been confirmed that the Ar ion beam energy was controlled by the acceleration voltage and the beam profile had good uniformity over the diameter of 80 mm. Dry etching of a Si wafer at the floating potential has been carried out by Ar NB. Si sputtering yield by an Ar NB clearly depends on the acceleration voltage. This result shows that the NB has been generated through the charge exchange reaction from the ion beam in the process chamber. (author)

  10. Configurations of Parental Preferences Concerning Sources of Sex Education for Adolescents

    Science.gov (United States)

    Libby, Roger W.; And Others

    1974-01-01

    The research purpose of this study was not merely parental preferences concerning sources of sex education for adolescents, but more importantly, parental preferences of combinations of social institutions as sources of sex education. (Author)

  11. Electron backstream to the source plasma region in an ion source

    International Nuclear Information System (INIS)

    Ohara, Y.; Akiba, M.; Arakawa, Y.; Okumura, Y.; Sakuraba, J.

    1980-01-01

    The flux of backstream electrons to the source plasma region increases significantly with the acceleration voltage of an ion beam, so that the back plate in the arc chamber should be broken for quasi-dc operation. The flux of backstream electrons is estimated at the acceleration voltage of 50--100 kV for a proton beam with the aid of ion beam simulation code. The power flux of backstream electrons is up to about 7% of the total beam output at the acceleration voltage of 75 kV. It is pointed out that the conventional ion sources such as the duoPIGatron or the bucket source which use a magnetic field for source plasma production are not suitable for quasi-dc and high-energy ion sources, because the surface heat flux of the back plate is increased by the focusing of backstream electrons and the removal of it is quite difficult. A new ion source which has an electron beam dump in the arc chamber is proposed

  12. RS-20 type repetitive generator with planar configuration of plasma opening switch

    Energy Technology Data Exchange (ETDEWEB)

    Agalakov, V P; Barinov, N U; Belenki, G S [Kurchatov Inst., Moscow (Russian Federation); and others

    1997-12-31

    The existing experience with the production of repetitive rate accelerators with a high peak power (in excess of 10{sup 10} W) and an average power above 50 kW makes it possible to resolve a number of physics and technology tasks which are connected with the reliability and life of the accelerator. The design and results on optimization of a simple plasma opening switch (POS) are discussed. The final design of the POS provided voltages of up to 2 MV and had a life of more than 105 pulses including 4 hours of continuous operation under 4 Hz repetition rate and wall plug power 65 kW. This unit was tested at the RS-20 type accelerator both at the Kurchatov Institute and at the Northwest Institute of Nuclear Technology in China. (author). 5 figs., 1 ref.

  13. KINETIC-J: A computational kernel for solving the linearized Vlasov equation applied to calculations of the kinetic, configuration space plasma current for time harmonic wave electric fields

    Science.gov (United States)

    Green, David L.; Berry, Lee A.; Simpson, Adam B.; Younkin, Timothy R.

    2018-04-01

    We present the KINETIC-J code, a computational kernel for evaluating the linearized Vlasov equation with application to calculating the kinetic plasma response (current) to an applied time harmonic wave electric field. This code addresses the need for a configuration space evaluation of the plasma current to enable kinetic full-wave solvers for waves in hot plasmas to move beyond the limitations of the traditional Fourier spectral methods. We benchmark the kernel via comparison with the standard k →-space forms of the hot plasma conductivity tensor.

  14. The gridless plasma ion source (GIS) for plasma ion assisted optical coating

    International Nuclear Information System (INIS)

    You Dawei; Li Xiaoqian; Wang Yu; Lin Yongchang

    2004-01-01

    High-quality optical coating is a key technology for modern optics. Ion-assisted deposition technology was used to improve the vaporized coating in 1980's. The GIS (gridless ion source), which is an advanced plasma source for producing a high-quality optical coating in large area, can produce a large area uniformity>1000 mm (diameter), a high ion current density ∼0.5 mA/cm 2 , 20 eV-200 eV energetic plasma ions and can activate reactive gas and film atoms. Now we have developed a GIS system. The GIS and the plasma ion-assisted deposition technology are investigated to achieve a high-quality optical coating. The GIS is a high power and high current source with a power of 1 kW-7.5 kW, a current of 10 A- 70 A and an ion density of 200 μA/cm 2 -500 μA/cm 2 . Because of the special magnetic structure, the plasma-ion extraction efficiency has been improved to obtain a maximum ion density of 500 μA/cm 2 in the medium power (∼4 kW) level. The GIS applied is of a special cathode structure, so that the GIS operation can be maintained under a rather low power and the lifetime of cathode will be extended. The GIS has been installed in the LPSX-1200 type box coating system. The coated TiO 2 , SiO 2 films such as antireflective films with the system have the same performance reported by Leybold Co, 1992, along with a controllable refractive index and film structure. (authors)

  15. Influence of source configuration on spectral composition of gamma-ray beams from 60Co teletherapy units

    International Nuclear Information System (INIS)

    Ehrlich, M.; Soares, C.G.; Jackson, B.; Lanoue, P.

    1978-01-01

    Measurements were made of the photon spectra of simulated 60 Co teletherapy beams. Various source configurations and source environments of practical interest were employed for this purpose. The sources consisted of activated cobalt pellets packed into steel capsules. Several combinations of capsule diameters and heights of pellet layers were used. The spacer materials filling the remaining capsule volume were chosen to be of high, intermediate, or low atomic number. The capsules could be inserted, one at a time, into a compartment of either tungsten or brass, simulating the central section of popular commercial 60 Co teletherapy units. There also was some choice in the atomic number of the structural elements holding the capsules in place in the compartment. The largest contribution of scattered photons was found to occur when the materials close to the source pellets had atomic numbers in the vicinity of 30. (author)

  16. Magnetic configuration effects on the edge heat flux in the limiter plasma on W7-X measured using the infrared camera and the combined probe

    Science.gov (United States)

    P, DREWS; H, NIEMANN; J, COSFELD; Y, GAO; J, GEIGER; O, GRULKE; M, HENKEL; D, HÖSCHEN; K, HOLLFELD; C, KILLER; A, KRÄMER-FLECKEN; Y, LIANG; S, LIU; D, NICOLAI; O, NEUBAUER; M, RACK; B, SCHWEER; G, SATHEESWARAN; L, RUDISCHHAUSER; N, SANDRI; N, WANG; the W7-X Team

    2018-05-01

    Controlling the heat and particle fluxes in the plasma edge and on the plasma facing components is important for the safe and effective operation of every magnetically confined fusion device. This was attempted on Wendelstein 7-X in the first operational campaign, with the modification of the magnetic configuration by use of the trim coils and tuning the field coil currents, commonly named iota scan. Ideally, the heat loads on the five limiters are equal. However, they differ between each limiter and are non-uniform, due to the (relatively small) error fields caused by the misalignment of components. It is therefore necessary to study the influence of the configuration changes on the transport of heat and particles in the plasma edge caused by the application of error fields and the change of the magnetic configuration. In this paper the up-stream measurements conducted with the combined probe are compared to the downstream measurements with the DIAS infrared camera on the limiter.

  17. Theory for beam-plasma millimeter-wave radiation source experiments

    International Nuclear Information System (INIS)

    Rosenberg, M.; Krall, N.A.

    1989-01-01

    This paper reports on theoretical studies for millimeter-wave plasma source experiments. In the device, millimeter-wave radiation is generated in a plasma-filled waveguide driven by counter-streaming electron beams. The beams excite electron plasma waves which couple to produce radiation at twice the plasma frequency. Physics topics relevant to the high electron beam current regime are discussed

  18. Discharge physics and chemistry of a novel atmospheric pressure plasma source

    Energy Technology Data Exchange (ETDEWEB)

    Park, J.; Henins, I.; Hermann, J.W.; Selwyn, G.S.; Jeong, J.Y.; Hickis, R.

    1999-07-01

    The atmospheric pressure plasma jet (APPJ) is a unique plasma source operating at atmospheric pressure. The APPJ operates with RF power and produces a stable non-thermal discharge in capacitively-coupled configuration. The discharge is spatially and temporally homogeneous and provides a unique gas phase chemistry that is well suited for various applications including etching, film deposition, surface treatment and decontamination of chemical and biological warfare (CBW) agents. A theoretical model shows electron densities of 0.2--2 x 10{sup 11} cm{sup {minus}3} for a helium discharge at a power level of 3--30 W cm{sup {minus}3}. The APPJ also produces a large flux, equivalent of up to 10,000 monolayer s{sup {minus}1}, of chemically-active, atomic and metastable molecular species which can impinge surfaces several cm downstream of the confined source. In addition, the efforts are in progress to measure the electron density using microwave diagnostics and to benchmark the gas phase chemical model by using LIF and titration.

  19. Effects of internal structure on equilibrium of field-reversed configuration plasma sustained by rotating magnetic field

    International Nuclear Information System (INIS)

    Yambe, Kiyoyuki; Inomoto, Michiaki; Okada, Shigefumi; Kobayashi, Yuka; Asai, Tomohiko

    2008-01-01

    The effects of an internal structure on the equilibrium of a field-reversed configuration (FRC) plasma sustained by rotating magnetic field is investigated by using detailed electrostatic probe measurements in the FRC Injection Experiment apparatus [S. Okada, et al., Nucl. Fusion. 45, 1094 (2005)]. An internal structure installed axially on the geometrical axis, which simulates Ohmic transformer or external toroidal field coils on the FRC device, brings about substantial changes in plasma density profile. The internal structure generates steep density-gradients not only on the inner side but on the outer side of the torus. The radial electric field is observed to sustain the ion thermal pressure-gradient in the FRC without the internal structure; however, the radial electric field is not sufficient to sustain the increased ion thermal pressure-gradient in the FRC with the internal structure. Spontaneously driven azimuthal ion flow will be accountable for the imbalance of the radial pressure which is modified by the internal structure.

  20. Discharge plasmas as EUV Sources for Future Micro Lithography

    Science.gov (United States)

    Kruecken, Thomas

    2007-08-01

    Future extreme ultraviolet (EUV) lithography will require very high radiation intensities in a narrow wavelength range around 13.5 nm, which is most efficiently emitted as line radiation by highly ionized heavy particles. Currently the most intense EUV sources are based on xenon or tin gas discharges. After having investigated the limits of a hollow cathode triggered xenon pinch discharge Philips Extreme UV favors a laser triggered tin vacuum spark discharge. Plasma and radiation properties of these highly transient discharges will be compared. Besides simple MHD-models the ADAS software package has been used to generate important atomic and spectral data of the relevant ion stages. To compute excitation and radiation properties, collisional radiative equilibria of individual ion stages are computed. For many lines opacity effects cannot be neglected. In the xenon discharges the optical depths allow for a treatment based on escape factors. Due to the rapid change of plasma parameters the abundancies of the different ionization stages must be computed dynamically. This requires effective ionization and recombination rates, which can also be supplied by ADAS. Due to very steep gradients (up to a couple orders of magnitude per mm) the plasma of tin vacuum spark discharges is very complicated. Therefore we shall describe here only some technological aspects of our tin EUV lamp: The electrode system consists of two rotating which are pulled through baths of molten tin such that a tin film remains on their surfaces. With a laser pulse some tin is ablated from one of the wheels and travels rapidly through vacuum towards the other rotating wheel. When the tin plasma reaches the other electrodes it ignites and the high current phase starts, i.e. the capacitor bank is unloaded, the plasma is pinched and EUV is radiated. Besides the good spectral properties of tin this concept has some other advantages: Erosion of electrodes is no severe problem as the tin film is

  1. A New Configuration for Power Sharing of Two Z-Source Inverters

    Directory of Open Access Journals (Sweden)

    M. Ghani varzaneh

    2017-09-01

    Full Text Available This paper presents a new structure to provide the ability for power sharing of two Z-source inverters. According to the operation principles of Z-source inverters, only one input source supplies the circuit, which is a limitation particularly for the stand alone systems feeded by limited output power such as photovoltaics and feul cells. Furthermore; if one source fails to supply,  the load can't be supplied. This paper covers those via interconnection of impedance network of two Z-source inverters. The operating principles of the proposed topology for the stand-alone and power sharing conditions are described and the relations are derived. The topology is simulated, which the results verify the theoretical analysis and well performance of the system. 

  2. Configurations and implementation of payroll system using open source erp: a case study of Koperasi PT Sri

    Science.gov (United States)

    Terminanto, A.; Swantoro, H. A.; Hidayanto, A. N.

    2017-12-01

    Enterprise Resource Planning (ERP) is an integrated information system to manage business processes of companies of various business scales. Because of the high cost of ERP investment, ERP implementation is usually done in large-scale enterprises, Due to the complexity of implementation problems, the success rate of ERP implementation is still low. Open Source System ERP becomes an alternative choice of ERP application to SME companies in terms of cost and customization. This study aims to identify characteristics and configure the implementation of OSS ERP Payroll module in KKPS (Employee Cooperative PT SRI) using OSS ERP Odoo and using ASAP method. This study is classified into case study research and action research. Implementation of OSS ERP Payroll module is done because the HR section of KKPS has not been integrated with other parts. The results of this study are the characteristics and configuration of OSS ERP payroll module in KKPS.

  3. Dynamic sheath studies in plasma source ion implantation

    International Nuclear Information System (INIS)

    Schever, J.T.; Shamim, M.; Conrad, J.R.

    1990-01-01

    Plasma Source Ion Implantation (PSII) is a non-line-of-sight method for materials processing in which a target is immersed in a plasma and pulse biased to a high negative voltage (∼ 50 kV). A model of the dynamic sheath which forms under these conditions has been developed and applied to planar, cylindrical and spherical geometries. This model assumes that the transient sheath obeys the Child-Langmuir law for space charge limited emission at each instant during the propagation. Ions uncovered by the propagating sheath edge supply the space charge limited current. This yields an equation relating sheath edge velocity to position, which can be integrated to obtain the sheath edge position as a function of time. The same procedure used in cylindrical and spherical geometry results in a similar equation which must be integrated numerically. Comparison of results of experimental measurements, our model and simulation will be presented for the dynamic sheath edge position and target current waveform. Measurements of implanted dose uniformity of wedge shaped targets are also presented

  4. Materials science issues of plasma source ion implantation

    International Nuclear Information System (INIS)

    Nastasi, M.; Faehl, R.J.; Elmoursi, A.A.

    1996-01-01

    Ion beam processing, including ion implantation and ion beam assisted deposition (IBAD), are established surface modification techniques which have been used successfully to synthesize materials for a wide variety of tribological applications. In spite of the flexibility and promise of the technique, ion beam processing has been considered too expensive for mass production applications. However, an emerging technology, Plasma Source Ion Implantation (PSII), has the potential of overcoming these limitations to become an economically viable tool for mass industrial applications. In PSII, targets are placed directly in a plasma and then pulsed-biased to produce a non-line-of-sight process for intricate target geometries without complicated fixturing. If the bias is a relatively high negative potential (20--100 kV) ion implantation will result. At lower voltages (50--1,200 V), deposition occurs. Potential applications for PSII are in low-value-added products such as tools used in manufacturing, orthopedic devices, and the production of wear coatings for hard disk media. This paper will focus on the technology and materials science associated with PSII

  5. Note: Triggering behavior of a vacuum arc plasma source

    Energy Technology Data Exchange (ETDEWEB)

    Lan, C. H., E-mail: lanchaohui@163.com; Long, J. D.; Zheng, L.; Dong, P.; Yang, Z.; Li, J.; Wang, T.; He, J. L. [Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900 (China)

    2016-08-15

    Axial symmetry of discharge is very important for application of vacuum arc plasma. It is discovered that the triggering method is a significant factor that would influence the symmetry of arc discharge at the final stable stage. Using high-speed multiframe photography, the transition processes from cathode-trigger discharge to cathode-anode discharge were observed. It is shown that the performances of the two triggering methods investigated are quite different. Arc discharge triggered by independent electric source can be stabilized at the center of anode grid, but it is difficult to achieve such good symmetry through resistance triggering. It is also found that the triggering process is highly correlated to the behavior of emitted electrons.

  6. Directional sound beam emission from a configurable compact multi-source system

    KAUST Repository

    Zhao, Jiajun; Jadhali, Rasha Al; Zhang, Likun; Wu, Ying

    2018-01-01

    We propose to achieve efficient emission of highly directional sound beams from multiple monopole sources embedded in a subwavelength enclosure. Without the enclosure, the emitted sound fields have an indistinguishable or omnidirectional radiation

  7. An improved barium plasma source for q-machines

    International Nuclear Information System (INIS)

    Paris, P.J.; Gorgerat, P.; Simik, A.; Rynn, N.; Roe, S.; Schleipen, M.

    1988-06-01

    We have developed a stable q-machine with well determined parameters for long term times, of constant plasma density and temperature. The plasma characteristics and gun behaviour allow research in fundamental plasma physics, especially with the use of non perturbing powerful optical (LIF) diagnostics in the determination of many of the plasma parameters. (author) 17 figs., 2 tabs., 7 refs

  8. Hall Current Plasma Source Having a Center-Mounted or a Surface-Mounted Cathode

    Science.gov (United States)

    Martinez, Rafael A. (Inventor); Williams, John D. (Inventor); Moritz, Jr., Joel A. (Inventor); Farnell, Casey C. (Inventor)

    2018-01-01

    A miniature Hall current plasma source apparatus having magnetic shielding of the walls from ionized plasma, an integrated discharge channel and gas distributor, an instant-start hollow cathode mounted to the plasma source, and an externally mounted keeper, is described. The apparatus offers advantages over other Hall current plasma sources having similar power levels, including: lower mass, longer lifetime, lower part count including fewer power supplies, and the ability to be continuously adjustable to lower average power levels using pulsed operation and adjustment of the pulse duty cycle. The Hall current plasma source can provide propulsion for small spacecraft that either do not have sufficient power to accommodate a propulsion system or do not have available volume to incorporate the larger propulsion systems currently available. The present low-power Hall current plasma source can be used to provide energetic ions to assist the deposition of thin films in plasma processing applications.

  9. Study on surface modification of polymer films by using atmospheric plasma jet source

    International Nuclear Information System (INIS)

    Takemura, Yuichiro; Hara, Tamio; Yamaguchi, Naohiro

    2008-01-01

    Reactive gas plasma treatments of poly(ethylene terephthalate) (PET) and polyimide (Kapton) have been performed using an atmospheric plasmas jet source. Characteristics of surface modification have been examined by changing the distance between the plasma jet source and the treated sample, and by changing the working gas spaces. Simultaneously, each plasma jet source has been investigated by space-resolving spectroscopy in the UV/visible region. Polymer surfaces have been analyzed by X-ray photoelectron spectroscopy (XPS). A marked improvement in the hydrophilicity of the polymer surfaces has been made by using N 2 or O 2 plasma jet source with a very short exposure time of about 0.01 s, whereas the less improvement has been obtained using on air plasma jet source because of NO x compound production. Changes in the chemical states of C of the polymer surfaces have been observed in XPS spectra after N 2 plasma jet spraying. (author)

  10. Plasma focus as an heavy ion source in the problem of heavy ion fusion

    International Nuclear Information System (INIS)

    Gribkov, V.A.; Dubrovskij, A.V.; Kalachev, N.V.; Krokhin, O.N.; Silin, P.V.; Nikulin, V.Ya.; Cheblukov, Yu.N.

    1984-01-01

    Results of experiments on the ion flux formation in a plasma focus (PF) to develop a multicharged ion source for thermonuclear facility driver are presented. In plasma focus accelerating section copper ions were injected. Advantages of the suggested method of ion beam formation are demonstrated. Beam emittance equalling < 0.1 cmxmrad is obtained. Plasma focus ion energy exceeds 1 MeV. Plasma focus in combination with a neodymium laser is thought to be a perspective ion source for heavy ion fusion

  11. Synchronized and configurable source of electrical pulses for x-ray pump-probe experiments

    International Nuclear Information System (INIS)

    Strachan, J. P.; Chembrolu, V.; Yu, X. W.; Tyliszczak, T.; Acremann, Y.

    2007-01-01

    A method is described for the generation of software tunable patterns of nanosecond electrical pulses. The bipolar, high repetition rate (up to 250 MHz), fast rise time (<30 ps), square pulses are suitable for applications such as the excitation sequence in dynamic pump-probe experiments. Synchronization with the time structure of a synchrotron facility is possible as well as fine control of the relative delay in steps of 10 ps. The pulse generator described here is used to excite magnetic nanostructures with current pulses. Having an excitation system which can match the high repetition rate of a synchrotron allows for utilization of the full x-ray flux and is needed in experiments which require a large photon flux. The fast rise times allow for picosecond time resolution in pump-probe experiments. All pulse pattern parameters are configurable by software

  12. On the possibility of forming a thermonuclear plasma by the injection of accelerated ions into a magnetic mirror configuration

    International Nuclear Information System (INIS)

    Prevot, Francois; Hubert, Pierre; Gourdon, Christian

    1959-01-01

    It is proposed to form a plasma at very high temperature by injection of fast molecular ions into a magnetic field, in such a way that the ions injected from a ring-shaped source pass through the revolution axis of the system and are dissociated from it. The properties of this movement provide reason to hope for favourable performances from this type of injection. A numerical example of its application is given. Reprint of a paper published in Comptes rendus des seances de l'Academie des Sciences, t. 249, p. 997-999, sitting of 14 September 1959 [fr

  13. Shielding Characteristics Using an Ultrasonic Configurable Fan Artificial Noise Source to Generate Modes - Experimental Measurements and Analytical Predictions

    Science.gov (United States)

    Sutliff, Daniel L.; Walker, Bruce E.

    2014-01-01

    An Ultrasonic Configurable Fan Artificial Noise Source (UCFANS) was designed, built, and tested in support of the NASA Langley Research Center's 14x22 wind tunnel test of the Hybrid Wing Body (HWB) full 3-D 5.8% scale model. The UCFANS is a 5.8% rapid prototype scale model of a high-bypass turbofan engine that can generate the tonal signature of proposed engines using artificial sources (no flow). The purpose of the program was to provide an estimate of the acoustic shielding benefits possible from mounting an engine on the upper surface of a wing; a flat plate model was used as the shielding surface. Simple analytical simulations were used to preview the radiation patterns - Fresnel knife-edge diffraction was coupled with a dense phased array of point sources to compute shielded and unshielded sound pressure distributions for potential test geometries and excitation modes. Contour plots of sound pressure levels, and integrated power levels, from nacelle alone and shielded configurations for both the experimental measurements and the analytical predictions are presented in this paper.

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

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jin-Won; Lee, Yun-Seong, E-mail: leeeeys@kaist.ac.kr; Chang, Hong-Young [Low-temperature Plasma Laboratory, Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 305-701 (Korea, Republic of); An, Sang-Hyuk [Agency of Defense Development, Yuseong-gu, Daejeon 305-151 (Korea, Republic of)

    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.

  15. An inexpensive way to analyze the optics of electrostatic, surface-ionization ion-source configurations

    International Nuclear Information System (INIS)

    Balestrini, S.J.

    1986-01-01

    The optical characteristics of surface ionization sources can often be studied in detail with the aid of a home computer. Sources with two-dimensional symmetry are considered. Ions are created on the surface of a hot filament. An accelerating voltage, V, is applied to the source and filament. The ions are accelerated and focused into a beam by a series of electrodes containing narrow axial slits. The ordering of elementary stages of acceleration that the electrodes form from is the optical stack. The focusing parameters are the fractions of the source voltage applied to the electrodes. A portion of the ions leaves the source through a beam-defining, collimating slit in the final electrode. An ion trajectory at any point along the symmetry axis is described by a vector with two phase space components, which are treated as small quantities. The components at the filament are ω, the displacement from the symmetry axis, and ν, the velocity component of the ion parallel to the filament surface divided by its speed when it leaves the first stage. Elsewhere, the trajectory components are the displacement from the symmetry axis and the slope

  16. Innovative ion sources for accelerators: the benefits of the plasma technology

    Czech Academy of Sciences Publication Activity Database

    Gammino, S.; Ciavola, G.; Celona, L.; Torrisi, L.; Ando, L.; Presti, M.; Láska, Leoš; Krása, Josef; Wolowski, J.

    2004-01-01

    Roč. 54, Suppl. C (2004), s. C883-C888 ISSN 0011-4626. [Symposium on Plasma Physics and Technology /21./. Praha, 14.06.2004-17.06.2004] R&D Projects: GA AV ČR IAA1010405 Institutional research plan: CEZ:AV0Z1010921 Keywords : plasma sources * ion sources * proton sources * ECR Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.292, year: 2004

  17. Jet outflow and open field line measurements on the C-2U advanced beam-driven field-reversed configuration plasma experiment.

    Science.gov (United States)

    Sheftman, D; Gupta, D; Roche, T; Thompson, M C; Giammanco, F; Conti, F; Marsili, P; Moreno, C D

    2016-11-01

    Knowledge and control of the axial outflow of plasma particles and energy along open-magnetic-field lines are of crucial importance to the stability and longevity of the advanced beam-driven field-reversed configuration plasma. An overview of the diagnostic methods used to perform measurements on the open field line plasma on C-2U is presented, including passive Doppler impurity spectroscopy, microwave interferometry, and triple Langmuir probe measurements. Results of these measurements provide the jet ion temperature and axial velocity, electron density, and high frequency density fluctuations.

  18. Electron cyclotron resonance ion source plasma characterization by X-ray spectroscopy and X-ray imaging

    Energy Technology Data Exchange (ETDEWEB)

    Mascali, David, E-mail: davidmascali@lns.infn.it; Castro, Giuseppe; Celona, Luigi; Neri, Lorenzo; Gammino, Santo [INFN–Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); Biri, Sándor; Rácz, Richárd; Pálinkás, József [Institute for Nuclear Research (Atomki), Hungarian Academy of Sciences, Bem tér 18/c, H-4026 Debrecen (Hungary); Caliri, Claudia [INFN–Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); Università degli Studi di Catania, Dip.to di Fisica e Astronomia, via Santa Sofia 64, 95123 Catania (Italy); Romano, Francesco Paolo [INFN–Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); CNR, Istituto per i Beni Archeologici e Monumentali, Via Biblioteca 4, 95124 Catania (Italy); Torrisi, Giuseppe [INFN–Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); Università Mediterranea di Reggio Calabria, DIIES, Via Graziella, I-89100 Reggio Calabria (Italy)

    2016-02-15

    An experimental campaign aiming to investigate electron cyclotron resonance (ECR) plasma X-ray emission has been recently carried out at the ECRISs—Electron Cyclotron Resonance Ion Sources laboratory of Atomki based on a collaboration between the Debrecen and Catania ECR teams. In a first series, the X-ray spectroscopy was performed through silicon drift detectors and high purity germanium detectors, characterizing the volumetric plasma emission. The on-purpose developed collimation system was suitable for direct plasma density evaluation, performed “on-line” during beam extraction and charge state distribution characterization. A campaign for correlating the plasma density and temperature with the output charge states and the beam intensity for different pumping wave frequencies, different magnetic field profiles, and single-gas/gas-mixing configurations was carried out. The results reveal a surprisingly very good agreement between warm-electron density fluctuations, output beam currents, and the calculated electromagnetic modal density of the plasma chamber. A charge-coupled device camera coupled to a small pin-hole allowing X-ray imaging was installed and numerous X-ray photos were taken in order to study the peculiarities of the ECRIS plasma structure.

  19. Compact tunable Compton x-ray source from laser-plasma accelerator and plasma mirror

    International Nuclear Information System (INIS)

    Tsai, Hai-En; Wang, Xiaoming; Shaw, Joseph M.; Li, Zhengyan; Zgadzaj, Rafal; Henderson, Watson; Downer, M. C.; Arefiev, Alexey V.; Zhang, Xi; Khudik, V.; Shvets, G.

    2015-01-01

    We present an in-depth experimental-computational study of the parameters necessary to optimize a tunable, quasi-monoenergetic, efficient, low-background Compton backscattering (CBS) x-ray source that is based on the self-aligned combination of a laser-plasma accelerator (LPA) and a plasma mirror (PM). The main findings are (1) an LPA driven in the blowout regime by 30 TW, 30 fs laser pulses produce not only a high-quality, tunable, quasi-monoenergetic electron beam, but also a high-quality, relativistically intense (a 0 ∼ 1) spent drive pulse that remains stable in profile and intensity over the LPA tuning range. (2) A thin plastic film near the gas jet exit retro-reflects the spent drive pulse efficiently into oncoming electrons to produce CBS x-rays without detectable bremsstrahlung background. Meanwhile, anomalous far-field divergence of the retro-reflected light demonstrates relativistic “denting” of the PM. Exploiting these optimized LPA and PM conditions, we demonstrate quasi-monoenergetic (50% FWHM energy spread), tunable (75–200 KeV) CBS x-rays, characteristics previously achieved only on more powerful laser systems by CBS of a split-off, counter-propagating pulse. Moreover, laser-to-x-ray photon conversion efficiency (∼6 × 10 −12 ) exceeds that of any previous LPA-based quasi-monoenergetic Compton source. Particle-in-cell simulations agree well with the measurements

  20. Feasibility study of Thermal Electric Generator Configurations as Renewable Energy Sources

    Science.gov (United States)

    Akmal Johar, Muhammad; Yahaya, Zulkarnain; Faizan Marwah, Omar Mohd; Jamaludin, Wan Akashah Wan; Najib Ribuan, Mohamed

    2017-10-01

    Thermoelectric Generator is a solid state device that able to convert thermal energy into electrical energy via temperature differences. The technology is based on Seebeck effect that was discovered in year 1821, however till now there is no real application to exploit this capability in mass scale. This research will report the performance analysis of TEG module in controlled environment of lab scale model. National Instrument equipment and Labview software has been choosen and developed to measure the TEG module in various configurations. Based on the experiment result, an additional passive cooling effort has produced a better ΔT by 7°C. The optimal electrical loading of single TEG is recorded at 200Ω. As for circuit connections, series connection has shown superior power output when compared to parallel connection or single TEG. A series connection of two TEGs has produced power output of 416.82μW when compared to other type connections that only produced around 100μW.

  1. Sequential Bayesian geoacoustic inversion for mobile and compact source-receiver configuration.

    Science.gov (United States)

    Carrière, Olivier; Hermand, Jean-Pierre

    2012-04-01

    Geoacoustic characterization of wide areas through inversion requires easily deployable configurations including free-drifting platforms, underwater gliders and autonomous vehicles, typically performing repeated transmissions during their course. In this paper, the inverse problem is formulated as sequential Bayesian filtering to take advantage of repeated transmission measurements. Nonlinear Kalman filters implement a random-walk model for geometry and environment and an acoustic propagation code in the measurement model. Data from MREA/BP07 sea trials are tested consisting of multitone and frequency-modulated signals (bands: 0.25-0.8 and 0.8-1.6 kHz) received on a shallow vertical array of four hydrophones 5-m spaced drifting over 0.7-1.6 km range. Space- and time-coherent processing are applied to the respective signal types. Kalman filter outputs are compared to a sequence of global optimizations performed independently on each received signal. For both signal types, the sequential approach is more accurate but also more efficient. Due to frequency diversity, the processing of modulated signals produces a more stable tracking. Although an extended Kalman filter provides comparable estimates of the tracked parameters, the ensemble Kalman filter is necessary to properly assess uncertainty. In spite of mild range dependence and simplified bottom model, all tracked geoacoustic parameters are consistent with high-resolution seismic profiling, core logging P-wave velocity, and previous inversion results with fixed geometries.

  2. Quasi-steady carbon plasma source for neutral beam injector

    International Nuclear Information System (INIS)

    Koguchi, H.; Sakakita, H.; Kiyama, S.; Shimada, T.; Sato, Y.; Hirano, Y.

    2014-01-01

    Carbon plasma is successfully sustained during 1000 s without any carrier gas in the bucket type ionization chamber with cusp magnetic field. Every several seconds, seed plasmas having ∼3 ms duration time are injected into the ionization chamber by a shunting arch plasma gun. The weakly ionized carbon plasma ejected from the shunting arch is also ionized by 2.45 GHz microwave at the electron cyclotron resonance surface and the plasma can be sustained even in the interval of gun discharges. Control of the gun discharge interval allows to keep high pressure and to sustain the plasma for long duration

  3. Quasi-steady carbon plasma source for neutral beam injector.

    Science.gov (United States)

    Koguchi, H; Sakakita, H; Kiyama, S; Shimada, T; Sato, Y; Hirano, Y

    2014-02-01

    Carbon plasma is successfully sustained during 1000 s without any carrier gas in the bucket type ionization chamber with cusp magnetic field. Every several seconds, seed plasmas having ∼3 ms duration time are injected into the ionization chamber by a shunting arch plasma gun. The weakly ionized carbon plasma ejected from the shunting arch is also ionized by 2.45 GHz microwave at the electron cyclotron resonance surface and the plasma can be sustained even in the interval of gun discharges. Control of the gun discharge interval allows to keep high pressure and to sustain the plasma for long duration.

  4. Perspective: The physics, diagnostics, and applications of atmospheric pressure low temperature plasma sources used in plasma medicine

    Science.gov (United States)

    Laroussi, M.; Lu, X.; Keidar, M.

    2017-07-01

    Low temperature plasmas have been used in various plasma processing applications for several decades. But it is only in the last thirty years or so that sources generating such plasmas at atmospheric pressure in reliable and stable ways have become more prevalent. First, in the late 1980s, the dielectric barrier discharge was used to generate relatively large volume diffuse plasmas at atmospheric pressure. Then, in the early 2000s, plasma jets that can launch cold plasma plumes in ambient air were developed. Extensive experimental and modeling work was carried out on both methods and much of the physics governing such sources was elucidated. Starting in the mid-1990s, low temperature plasma discharges have been used as sources of chemically reactive species that can be transported to interact with biological media, cells, and tissues and induce impactful biological effects. However, many of the biochemical pathways whereby plasma affects cells remain not well understood. This situation is changing rather quickly because the field, known today as "plasma medicine," has experienced exponential growth in the last few years thanks to a global research community that engaged in fundamental and applied research involving the use of cold plasma for the inactivation of bacteria, dental applications, wound healing, and the destruction of cancer cells/tumors. In this perspective, the authors first review the physics as well as the diagnostics of the principal plasma sources used in plasma medicine. Then, brief descriptions of their biomedical applications are presented. To conclude, the authors' personal assessment of the present status and future outlook of the field is given.

  5. Double-layer ion acceleration triggered by ion magnetization in expanding radiofrequency plasma sources

    International Nuclear Information System (INIS)

    Takahashi, Kazunori; Charles, Christine; Boswell, Rod W.; Fujiwara, Tamiya

    2010-01-01

    Ion energy distribution functions downstream of the source exit in magnetically expanding low-pressure plasmas are experimentally investigated for four source tube diameters ranging from about 5 to 15 cm. The magnetic-field threshold corresponding to a transition from a simple expanding plasma to a double layer-containing plasma is observed to increase with a decrease in the source tube diameter. The results demonstrate that for the four geometries, the double layer and the accelerated ion beam form when the ion Larmour radius in the source becomes smaller than the source tube radius, i.e., when the ions become magnetized in the source tube.

  6. Physics-electrical hybrid model for real time impedance matching and remote plasma characterization in RF plasma sources.

    Science.gov (United States)

    Sudhir, Dass; Bandyopadhyay, M; Chakraborty, A

    2016-02-01

    Plasma characterization and impedance matching are an integral part of any radio frequency (RF) based plasma source. In long pulse operation, particularly in high power operation where plasma load may vary due to different reasons (e.g. pressure and power), online tuning of impedance matching circuit and remote plasma density estimation are very useful. In some cases, due to remote interfaces, radio activation and, due to maintenance issues, power probes are not allowed to be incorporated in the ion source design for plasma characterization. Therefore, for characterization and impedance matching, more remote schemes are envisaged. Two such schemes by the same authors are suggested in these regards, which are based on air core transformer model of inductive coupled plasma (ICP) [M. Bandyopadhyay et al., Nucl. Fusion 55, 033017 (2015); D. Sudhir et al., Rev. Sci. Instrum. 85, 013510 (2014)]. However, the influence of the RF field interaction with the plasma to determine its impedance, a physics code HELIC [D. Arnush, Phys. Plasmas 7, 3042 (2000)] is coupled with the transformer model. This model can be useful for both types of RF sources, i.e., ICP and helicon sources.

  7. Hybrid Wing Body Shielding Studies Using an Ultrasonic Configurable Fan Artificial Noise Source Generating Typical Turbofan Modes

    Science.gov (United States)

    Sutliff, Daniel L.; Brown, Cliff; Walker, Bruce E.

    2014-01-01

    An Ultrasonic Configurable Fan Artificial Noise Source (UCFANS) was designed, built, and tested in support of the NASA Langley Research Center's 14x22 wind tunnel test of the Hybrid Wing Body (HWB) full 3-D 5.8% scale model. The UCFANS is a 5.8% rapid prototype scale model of a high-bypass turbofan engine that can generate the tonal signature of proposed engines using artificial sources (no flow). The purpose of the test was to provide an estimate of the acoustic shielding benefits possible from mounting the engine on the upper surface of an HWB aircraft using the projected signature of the engine currently proposed for the HWB. The modal structures at the rating points were generated from inlet and exhaust nacelle configurations - a flat plate model was used as the shielding surface and vertical control surfaces with correct plan form shapes were also tested to determine their additional impact on shielding. Radiated acoustic data were acquired from a traversing linear array of 13 microphones, spanning 36 inches. Two planes perpendicular, and two planes parallel, to the axis of the nacelle were acquired from the array sweep. In each plane the linear array traversed 4 sweeps, for a total span of 168 inches acquired. The resolution of the sweep is variable, so that points closer to the model are taken at a higher resolution. Contour plots of Sound Pressure Levels, and integrated Power Levels, from nacelle alone and shielded configurations are presented in this paper; as well as the in-duct mode power levels.

  8. Hybrid Wing Body Shielding Studies Using an Ultrasonic Configurable Fan Artificial Noise Source Generating Typical Turbofan Modes

    Science.gov (United States)

    Sutliff, Daniel l.; Brown, Clifford A.; Walker, Bruce E.

    2014-01-01

    An Ultrasonic Configurable Fan Artificial Noise Source (UCFANS) was designed, built, and tested in support of the NASA Langley Research Center's 14- by 22-ft wind tunnel test of the Hybrid Wing Body (HWB) full 3-D 5.8 percent scale model. The UCFANS is a 5.8 percent rapid prototype scale model of a high-bypass turbofan engine that can generate the tonal signature of proposed engines using artificial sources (no flow). The purpose of the test was to provide an estimate of the acoustic shielding benefits possible from mounting the engine on the upper surface of an HWB aircraft using the projected signature of the engine currently proposed for the HWB. The modal structures at the rating points were generated from inlet and exhaust nacelle configurations--a flat plate model was used as the shielding surface and vertical control surfaces with correct plan form shapes were also tested to determine their additional impact on shielding. Radiated acoustic data were acquired from a traversing linear array of 13 microphones, spanning 36 in. Two planes perpendicular, and two planes parallel, to the axis of the nacelle were acquired from the array sweep. In each plane the linear array traversed four sweeps, for a total span of 168 in. acquired. The resolution of the sweep is variable, so that points closer to the model are taken at a higher resolution. Contour plots of Sound Pressure Levels, and integrated Power Levels, from nacelle alone and shielded configurations are presented in this paper; as well as the in-duct mode power levels

  9. Ferroelectric plasma sources for NDCX-II and heavy ion drivers

    Energy Technology Data Exchange (ETDEWEB)

    Gilson, E.P., E-mail: egilson@pppl.gov [Princeton Plasma Physics Laboratory, Princeton University, P.O. Box 451, Princeton, New Jersey, 08543 (United States); Davidson, R.C.; Efthimion, P.C.; Kaganovich, I.D. [Princeton Plasma Physics Laboratory, Princeton University, P.O. Box 451, Princeton, New Jersey, 08543 (United States); Kwan, J.W.; Lidia, S.M.; Ni, P.A.; Roy, P.K.; Seidl, P.A.; Waldron, W.L. [Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, California, 94720 (United States); Barnard, J.J.; Friedman, A. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California, 94550 (United States)

    2014-01-01

    A barium titanate ferroelectric cylindrical plasma source has been developed, tested and delivered for the Neutralized Drift Compression Experiment NDCX-II at Lawrence Berkeley National Laboratory (LBNL). The plasma source design is based on the successful design of the NDCX-I plasma source. A 7 kV pulse applied across the 3.8 mm-thick ceramic cylinder wall produces a large polarization surface charge density that leads to breakdown and plasma formation. The plasma that fills the NDCX-II drift section upstream of the final-focusing solenoid has a plasma number density exceeding 10{sup 10} cm{sup −3} and an electron temperature of several eV. The operating principle of the ferroelectric plasma source are reviewed and a detailed description of the installation plans is presented. The criteria for plasma sources with larger number density will be given, and concepts will be presented for plasma sources for driver applications. Plasma sources for drivers will need to be highly reliable, and operate at several Hz for millions of shots.

  10. SCRIC: a code dedicated to the detailed emission and absorption of heterogeneous NLTE plasmas; application to xenon EUV sources; SCRIC: un code pour calculer l'absorption et l'emission detaillees de plasmas hors equilibre, inhomogenes et etendus; application aux sources EUV a base de xenon

    Energy Technology Data Exchange (ETDEWEB)

    Gaufridy de Dortan, F. de

    2006-07-01

    Nearly all spectral opacity codes for LTE and NLTE plasmas rely on configurations approximate modelling or even supra-configurations modelling for mid Z plasmas. But in some cases, configurations interaction (either relativistic and non relativistic) induces dramatic changes in spectral shapes. We propose here a new detailed emissivity code with configuration mixing to allow for a realistic description of complex mid Z plasmas. A collisional radiative calculation. based on HULLAC precise energies and cross sections. determines the populations. Detailed emissivities and opacities are then calculated and radiative transfer equation is resolved for wide inhomogeneous plasmas. This code is able to cope rapidly with very large amount of atomic data. It is therefore possible to use complex hydrodynamic files even on personal computers in a very limited time. We used this code for comparison with Xenon EUV sources within the framework of nano-lithography developments. It appears that configurations mixing strongly shifts satellite lines and must be included in the description of these sources to enhance their efficiency. (author)

  11. Numerical modeling of optical coherent transient processes with complex configurations-III: Noisy laser source

    International Nuclear Information System (INIS)

    Chang Tiejun; Tian Mingzhen

    2007-01-01

    A previously developed numerical model based on Maxwell-Bloch equations was modified to simulate optical coherent transient and spectral hole burning processes with noisy laser sources. Random walk phase noise was simulated using laser-phase sequences generated numerically according to the normal distribution of the phase shift. The noise model was tested by comparing the simulated spectral hole burning effect with the analytical solution. The noise effects on a few typical optical coherence transient processes were investigated using this numerical tool. Flicker and random walk frequency noises were considered in accumulation process

  12. Optimization of source and detector configurations based on Cramer-Rao lower bound analysis

    Science.gov (United States)

    Chen, Ling; Chen, Nanguang

    2011-03-01

    Optimization of source and detector (SD) arrangements in a diffuse optical tomography system is helpful for improving measurements' sensitivity to localized changes in imaging domain and enhancing the capacity of noise resistance. We introduced a rigorous and computationally efficient methodology and adapt it into the diffuse optics field to realize the optimizations of SD arrangements. Our method is based on Cramer-Rao lower bound analysis, which combines the diffusion-forward model and a noise model together. This method can be used to investigate the performance of the SD arrangements through quantitative estimations of lower bounds of the standard variances of the reconstructed perturbation depths and values. More importantly, it provides direct estimations of parameters without solving the inverse problem. Simulations are conducted in the reflection geometry to validate the effectiveness of the method on selections of the optimized SD sets, with a fixed number of sources and detectors, from an SD group on a planar probe surface. The impacts of different noise levels and target perturbation depths are considered in the simulations. It is demonstrated that the SD sets selected by this method afford better reconstructed images. This methodology can be adapted to other probe surfaces and other imaging geometries.

  13. The difference between the metal ion extracted from the R.F. ion source by applying plasma chemistry reaction and by non-plasma range chemistry reaction

    International Nuclear Information System (INIS)

    Bai Gui Bin

    1987-01-01

    The paper introduced the difference between using plasma chemistry reaction draw metal ion and non-plasma range chemistry reaction in the R.F. ion source. By using of the plasma chemistry reaction draw metal ion higher percentage than non-plasma range chemistry reaction in the R.F. ion source. The authors plasma chemistry reaction to R.F. ion source and implanter successfully. The effect is very well, it has its own characteristic

  14. Characterization of the effects of borehole configuration and interference with long term ground temperature modelling of ground source heat pumps

    International Nuclear Information System (INIS)

    Law, Ying Lam E.; Dworkin, Seth B.

    2016-01-01

    Highlights: • Long term ground temperature response is explored using finite element methods. • Simulation method is validated against experimental and analytical data. • Temperature changes at a fast rate in the first few years and slows down gradually. • ASHRAE recommended separation distances are not always sufficient. • Thermal accumulation occurs at the centre of borehole field. - Abstract: Ground source heat pumps (GSHPs) are an environmentally friendly alternative to conventional heating and cooling systems because of their high efficiency and low greenhouse gas emissions. The ground acts as a heat sink/source for the excess/required heat inside a building for cooling and heating modes, respectively. However, imbalance in heating and cooling needs can change ground temperature over the operating duration. This increase/decrease in ground temperature lowers system efficiency and causes the ground to foul—failing to accept or provide more heat. In order to ensure that GSHPs can operate to their designed conditions, thermal modelling is required to simulate the ground temperature during system operation. In addition, the borehole field layout can have a major impact on ground temperature. In this study, four buildings were studied—a hospital, fast-food restaurant, residence, and school, each with varying borehole configurations. Boreholes were modelled in a soil volume using finite-element methods and heating and cooling fluxes were applied to the borehole walls to simulate the GSHP operation. 20 years of operation were modelled for each building for 2 × 2, 4 × 4, and 2 × 8 borehole configurations. Results indicate that the borehole separation distance of 6 m, recommended by ASHRAE, is not always sufficient to prevent borehole thermal interactions. Benefits of using a 2 × 8 configuration as opposed to a 4 × 4 configuration, which can be observed because of the larger perimeter it provides for heat to dissipate to surrounding soil were

  15. Plasma particle sources due to interactions with neutrals in a turbulent scrape-off layer of a toroidally confined plasma

    DEFF Research Database (Denmark)

    Thrysøe, Alexander Simon; Løiten, M.; Madsen, J.

    2018-01-01

    The conditions in the edge and scrape-off layer (SOL) of magnetically confined plasmas determine the overall performance of the device, and it is of great importance to study and understand the mechanics that drive transport in those regions. If a significant amount of neutral molecules and atoms...... is present in the edge and SOL regions, those will influence the plasma parameters and thus the plasma confinement. In this paper, it is displayed how neutrals, described by a fluid model, introduce source terms in a plasma drift-fluid model due to inelastic collisions. The resulting source terms...... are included in a four-field drift fluid model, and it is shown how an increasing neutral particle density in the edge and SOL regions influences the plasma particle transport across the lastclosed-flux-surface. It is found that an appropriate gas puffing rate allows for the edge density in the simulation...

  16. Technological plasma source equipped with combined system of vacuum-arc discharge initiation

    International Nuclear Information System (INIS)

    Sysoev, Yu.O.

    2013-01-01

    The construction and the operation principle of erosion plasma source with a three-stage system of vacuum-arc discharge excitation is described. As first two step was used the modified contactless start system with plasma injector, which was widely used in standard plasma sources of the ''Bulat'' systems. The operation principle of the third stage was based on the transition of glow discharge to arc discharge. Coordinated operation of three stages during various stages of coating deposition provided significant increasing of service life and reliability of the system of vacuum-arc discharge initiation and extended the functionality of the plasma source

  17. Dependence of the source performance on plasma parameters at the BATMAN test facility

    Science.gov (United States)

    Wimmer, C.; Fantz, U.

    2015-04-01

    The investigation of the dependence of the source performance (high jH-, low je) for optimum Cs conditions on the plasma parameters at the BATMAN (Bavarian Test MAchine for Negative hydrogen ions) test facility is desirable in order to find key parameters for the operation of the source as well as to deepen the physical understanding. The most relevant source physics takes place in the extended boundary layer, which is the plasma layer with a thickness of several cm in front of the plasma grid: the production of H-, its transport through the plasma and its extraction, inevitably accompanied by the co-extraction of electrons. Hence, a link of the source performance with the plasma parameters in the extended boundary layer is expected. In order to characterize electron and negative hydrogen ion fluxes in the extended boundary layer, Cavity Ring-Down Spectroscopy and Langmuir probes have been applied for the measurement of the H- density and the determination of the plasma density, the plasma potential and the electron temperature, respectively. The plasma potential is of particular importance as it determines the sheath potential profile at the plasma grid: depending on the plasma grid bias relative to the plasma potential, a transition in the plasma sheath from an electron repelling to an electron attracting sheath takes place, influencing strongly the electron fraction of the bias current and thus the amount of co-extracted electrons. Dependencies of the source performance on the determined plasma parameters are presented for the comparison of two source pressures (0.6 Pa, 0.45 Pa) in hydrogen operation. The higher source pressure of 0.6 Pa is a standard point of operation at BATMAN with external magnets, whereas the lower pressure of 0.45 Pa is closer to the ITER requirements (p ≤ 0.3 Pa).

  18. Dependence of the source performance on plasma parameters at the BATMAN test facility

    International Nuclear Information System (INIS)

    Wimmer, C.; Fantz, U.

    2015-01-01

    The investigation of the dependence of the source performance (high j H − , low j e ) for optimum Cs conditions on the plasma parameters at the BATMAN (Bavarian Test MAchine for Negative hydrogen ions) test facility is desirable in order to find key parameters for the operation of the source as well as to deepen the physical understanding. The most relevant source physics takes place in the extended boundary layer, which is the plasma layer with a thickness of several cm in front of the plasma grid: the production of H − , its transport through the plasma and its extraction, inevitably accompanied by the co-extraction of electrons. Hence, a link of the source performance with the plasma parameters in the extended boundary layer is expected. In order to characterize electron and negative hydrogen ion fluxes in the extended boundary layer, Cavity Ring-Down Spectroscopy and Langmuir probes have been applied for the measurement of the H − density and the determination of the plasma density, the plasma potential and the electron temperature, respectively. The plasma potential is of particular importance as it determines the sheath potential profile at the plasma grid: depending on the plasma grid bias relative to the plasma potential, a transition in the plasma sheath from an electron repelling to an electron attracting sheath takes place, influencing strongly the electron fraction of the bias current and thus the amount of co-extracted electrons. Dependencies of the source performance on the determined plasma parameters are presented for the comparison of two source pressures (0.6 Pa, 0.45 Pa) in hydrogen operation. The higher source pressure of 0.6 Pa is a standard point of operation at BATMAN with external magnets, whereas the lower pressure of 0.45 Pa is closer to the ITER requirements (p ≤ 0.3 Pa)

  19. Sustainable application of renewable sources in water pumping systems: Optimized energy system configuration

    International Nuclear Information System (INIS)

    Ramos, J.S.; Ramos, H.M.

    2009-01-01

    Eighteen years ago, in Portugal, the expenses in a water supply system associated with energy consumption were quite low. However, with the successive crises of energy fuel and the increase of the energy tariff as well as the water demand, the energy consumption is becoming a larger and a more important part of the total budget of water supply pumping systems. Also, new governmental policies, essentially in developed countries, are trying to implement renewable energies. For these reasons, a case-study in Portugal of a water pumping system was analysed to operate connected to solar and wind energy sources. A stand-alone and a grid-connected systems were tested. The stand alone was compared with the cost of extending the national electric grid. In the grid-connected system two solutions were analysed, one with a water turbine and another without. To be able to implement a water turbine, a larger water pump was needed to pump the necessary water as for consumption as for energy production. For the case analysed the system without a water turbine proved to be more cost-effective because the energy tariff is not yet so competitive as well as the cost of water turbines

  20. Risk analysis of NPP in multi-unit site for configuration of AAC power source

    International Nuclear Information System (INIS)

    Kim, Myung Ki

    2000-01-01

    Because of the difficulties in finding new sites for nuclear power plants, more units are being added to the existing sites. In these multi-unit sites, appropriate countermeasures should be established to cope with the potential station blackout (SBO) accident. Currently, installation of additional diesel generator (DG) is considered to ensure an alternative AC power source, but it has not been decided yet how many DGs should be installed in a multi-unit site. In this paper, risk informed decision making method, which evaluates reliability of electrical system, core damage frequency, and site average core damage frequency, is introduced to draw up the suitable number of DG in multi-unit site. The analysis results show that installing two DGs lowered the site average core damage frequency by 1.4% compared to one DG in six unit site. In the light of risk-informed decisions in regulatory guide 1.174, there is no difference of safety between two alternatives. It is concluded that one emergency diesel generator sufficiently guarantees safety against station blackout of nuclear power plants in multi-unit site. (author)

  1. An Optimized Low-Charge Configuration of the LINAC Coherent Light Source

    CERN Document Server

    Emma, Paul; Huang, Zhirong; Limborg-Deprey, Cecile; Reiche, Sven; Wu, Juhao; Zolotorev, Max S

    2005-01-01

    The Linac Coherent Light Source (LCLS) is an x-ray free-electron laser (FEL) project based on the SLAC linac. The nominal parameter set is founded on a 1-nC bunch charge and normalized emittance of about 1 micron. The most challenging issues, such as emittance generation, wakefields, and coherent synchrotron radiation (CSR), are associated with the high bunch charge. In the LCLS in particular, with its strong linac wakefields, the bunch compression process produces sharp temporal horns at the head and tail of the bunch with degraded local emittance, effectively wasting much of the charge. The sharp horns intensify CSR in the bends and further drive a strong resistive-wall wakefield in the long FEL undulator. Although these issues are not insurmountable, they suggest a lower bunch charge may be more suitable. This study uses a 0.2-nC bunch charge and 0.85-micron emittance with only 30 A of peak current in the injector, producing the same FEL saturation length. The resulting performance is more stable, has negl...

  2. [Automatic adjustment control system for DC glow discharge plasma source].

    Science.gov (United States)

    Wan, Zhen-zhen; Wang, Yong-qing; Li, Xiao-jia; Wang, Hai-zhou; Shi, Ning

    2011-03-01

    There are three important parameters in the DC glow discharge process, the discharge current, discharge voltage and argon pressure in discharge source. These parameters influence each other during glow discharge process. This paper presents an automatic control system for DC glow discharge plasma source. This system collects and controls discharge voltage automatically by adjusting discharge source pressure while the discharge current is constant in the glow discharge process. The design concept, circuit principle and control program of this automatic control system are described. The accuracy is improved by this automatic control system with the method of reducing the complex operations and manual control errors. This system enhances the control accuracy of glow discharge voltage, and reduces the time to reach discharge voltage stability. The glow discharge voltage stability test results with automatic control system are provided as well, the accuracy with automatic control system is better than 1% FS which is improved from 4% FS by manual control. Time to reach discharge voltage stability has been shortened to within 30 s by automatic control from more than 90 s by manual control. Standard samples like middle-low alloy steel and tin bronze have been tested by this automatic control system. The concentration analysis precision has been significantly improved. The RSDs of all the test result are better than 3.5%. In middle-low alloy steel standard sample, the RSD range of concentration test result of Ti, Co and Mn elements is reduced from 3.0%-4.3% by manual control to 1.7%-2.4% by automatic control, and that for S and Mo is also reduced from 5.2%-5.9% to 3.3%-3.5%. In tin bronze standard sample, the RSD range of Sn, Zn and Al elements is reduced from 2.6%-4.4% to 1.0%-2.4%, and that for Si, Ni and Fe is reduced from 6.6%-13.9% to 2.6%-3.5%. The test data is also shown in this paper.

  3. Plasma ion sources and ion beam technology in microfabrications

    International Nuclear Information System (INIS)

    Ji, Lili

    2007-01-01

    For over decades, focused ion beam (FIB) has been playing a very important role in microscale technology and research, among which, semiconductor microfabrication is one of its biggest application area. As the dimensions of IC devices are scaled down, it has shown the need for new ion beam tools and new approaches to the fabrication of small-scale devices. In the meanwhile, nanotechnology has also deeply involved in material science research and bioresearch in recent years. The conventional FIB systems which utilize liquid gallium ion sources to achieve nanometer scale resolution can no longer meet the various requirements raised from such a wide application area such as low contamination, high throughput and so on. The drive towards controlling materials properties at nanometer length scales relies on the availability of efficient tools. In this thesis, three novel ion beam tools have been developed and investigated as the alternatives for the conventional FIB systems in some particular applications. An integrated focused ion beam (FIB) and scanning electron microscope (SEM) system has been developed for direct doping or surface modification. This new instrument employs a mini-RF driven plasma source to generate focused ion beam with various ion species, a FEI two-lens electron (2LE) column for SEM imaging, and a five-axis manipulator system for sample positioning. An all-electrostatic two-lens column has been designed to focus the ion beam extracted from the source. Based on the Munro ion optics simulation, beam spot sizes as small as 100 nm can be achieved at beam energies between 5 to 35 keV if a 5 (micro)m-diameter extraction aperture is used. Smaller beam spot sizes can be obtained with smaller apertures at sacrifice of some beam current. The FEI 2LE column, which utilizes Schottky emission, electrostatic focusing optics, and stacked-disk column construction, can provide high-resolution (as small as 20 nm) imaging capability, with fairly long working distance

  4. Dry reforming of methane via plasma-catalysis: influence of the catalyst nature supported on alumina in a packed-bed DBD configuration

    Science.gov (United States)

    Brune, L.; Ozkan, A.; Genty, E.; Visart de Bocarmé, T.; Reniers, F.

    2018-06-01

    These days, the consideration of CO2 as a feedstock has become the subject of more interest. The reutilization of CO2 is already possible via cold plasma techniques operating at atmospheric pressure. A promising technology is the dielectric barrier discharge (DBD). In most cases DBDs exhibit a low energy efficiency for CO2 conversion. However, several routes can be used to increase this efficiency and hence, the product formation. One of these routes is the packed-bed DBD configuration with porous beads inside the gap of the DBD, which also allows the coupling of plasma with catalysis. Catalysts can be introduced in such a configuration to exploit the synergistic effect between plasma and catalytically active surfaces, leading to a more efficient process. In this article, the dry reforming of methane (DRM) is studied, which aims to convert both CO2 and CH4, another greenhouse gas, at the same time. The conversions and energy costs of the DRM process are investigated and compared in both the packed-bed DBD configurations containing catalysts (Co, Cu or Ni) and the classical DBD. The change in filamentary behavior is studied in detail and correlated with the obtained conversions using gas chromatography, mass spectrometry and using an oscilloscope. A characterization of the catalysts on the beads is also carried out. Both the CO2 and CH4 conversions are clearly increased with the plasma-catalysis. Moreover, CH4 conversions as high as 90% can be obtained in certain conditions with copper catalysts.

  5. Development of Langmuir probe diagnostic system for 13.56 MHz plasma sources

    International Nuclear Information System (INIS)

    Ranjini, K.; Nabhiraj, P.Y.; Mallik, C.; Bhandari, R.K.

    2006-01-01

    A work on development of high brightness ion source has been started recently. Plasma parameters are strongly linked to the brightness of the ion beams produced from the ion sources. A self compensated Langmuir probe and related automation system for the measurement of plasma parameters is developed. This paper describes design of the probe, software, hardware and the results. (author)

  6. PIII Plasma Density Enhancement by a New DC Power Source

    International Nuclear Information System (INIS)

    Lopez-Callejas, R.; Godoy-Cabrera, O. G.; Granda-Gutierrez, E. E.; Piedad-Beneitez, A. de la; Munoz-Castro, A. E.; Valencia A, R.; Barocio, S. R.; Mercado-Cabrera, A.; Pena-Eguiluz, R.

    2006-01-01

    In practical terms, those plasmas produced by a DC voltage power supply do not attain densities above the 108 to 109 cm-3 band. Here we present a power supply, controlled in current and voltage, which has been successfully designed and constructed delivering plasma densities in the orders of 109 - 1010 cm-3. Its experimental performance test was conducted within one toroidal and one cylindrical chambers capable of 29 and 35 litres, respectively, using nitrogen gas. The DC plasma was characterized by a double electric probe. Several physical phenomena present in the PIII process have been keenly investigated including plasma sheath dynamics, interaction of plasma and surface, etc. In this paper we analyze the effect of the implantation voltage, plasma density and pulse time in the PIII average heating power and fluence density

  7. Two configurations of miniature Mirau interferometry for swept-source OCT imaging: applications in dermatology and gastroendoscopy

    Science.gov (United States)

    Gorecki, Christophe

    2015-08-01

    The early diagnosis of cancer is essential since it can be treated more effectively when detected earlier. Visual inspection followed by histological examination is, still today, the gold standard for clinicians. However, a large number of unnecessary surgical procedures are still performed. New diagnostics aids are emerging including the recent techniques of optical coherence tomography (OCT) which permits non-invasive 3D optical biopsies of biological tissues, improving patient's quality of life. Nevertheless, the existing bulk or fiber optics systems are expensive, only affordable at the hospital and thus, not sufficiently used by physicians or cancer's specialists as an early diagnosis tool. We developed two different microsystems based on Mirau interferometry and applied for swept source OCT imaging: one for dermatology and second for gastroenterology. In both cases the architecture is based tem based on spectrally tuned Mirau interferometry. The first configuration, developed in the frame of the European project VIAMOS, includes an active array of 4x4 Mirau interferometers. The matrix of Mirau reference mirrors is integrated on top of an electrostatic vertical comb-drive actuator. In second configuration, developed in the frame of Labex ACTION, we adapted VIAMOS technology to develop an OCT endomicroscope with a single-channel passive Mirau interferometer.

  8. Doubly and triply excited states for different plasma sources

    International Nuclear Information System (INIS)

    More, R.M.; Safronova, U.I.

    2000-01-01

    Autoionizing rates of doubly excited states as nln'l' configurations with n=2-9 and n'=2-9 are calculated. Analytical expressions of decay amplitude for two-electron system are derived. Expressions for autoionizing rates with averaging over LS are obtained for many-electron systems. The n and l dependence of doubly excited states as nln'l' configurations are investigated. (author)

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

    Directory of Open Access Journals (Sweden)

    Adam B. Sefkow

    2008-07-01

    Full Text Available Large-space-scale and long-time-scale plasma flow simulations are executed in order to study the spatial and temporal evolution of plasma parameters for two types of plasma sources used in the neutralized drift compression experiment (NDCX. The results help assess the charge neutralization conditions for ion beam compression experiments and can be employed in more sophisticated simulations, which previously neglected the dynamical evolution of the plasma. Three-dimensional simulations of a filtered cathodic-arc plasma source show the coupling efficiency of the plasma flow from the source to the drift region depends on geometrical factors. The nonuniform magnetic topology complicates the well-known general analytical considerations for evaluating guiding-center drifts, and particle-in-cell simulations provide a self-consistent evaluation of the physics in an otherwise challenging scenario. Plasma flow profiles of a ferroelectric plasma source demonstrate that the densities required for longitudinal compression experiments involving ion beams are provided over the drift length, and are in good agreement with measurements. Simulations involving azimuthally asymmetric plasma creation conditions show that symmetric profiles are nevertheless achieved at the time of peak on-axis plasma density. Also, the ferroelectric plasma expands upstream on the thermal expansion time scale, and therefore avoids the possibility of penetration into the acceleration gap and transport sections, where partial neutralization would increase the beam emittance. Future experiments on NDCX will investigate the transverse focusing of an axially compressing intense charge bunch to a sub-mm spot size with coincident focal planes using a strong final-focus solenoid. In order to fill a multi-tesla solenoid with the necessary high-density plasma for beam charge neutralization, the simulations predict that supersonically injected plasma from the low-field region will penetrate and

  10. Progress in the Development of a High Power Helicon Plasma Source for the Materials Plasma Exposure Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Goulding, Richard Howell [ORNL; Caughman, John B. [ORNL; Rapp, Juergen [ORNL; Biewer, Theodore M. [ORNL; Bigelow, Tim S. [ORNL; Campbell, Ian H. [ORNL; Caneses Marin, Juan F. [ORNL; Donovan, David C. [ORNL; Kafle, Nischal [ORNL; Martin, Elijah H. [ORNL; Ray, Holly B. [ORNL; Shaw, Guinevere C. [ORNL; Showers, Melissa A. [ORNL

    2017-09-01

    Proto-MPEX is a linear plasma device being used to study a novel RF source concept for the planned Material Plasma Exposure eXperiment (MPEX), which will address plasma-materials interaction (PMI) for nuclear fusion reactors. Plasmas are produced using a large diameter helicon source operating at a frequency of 13.56 MHz at power levels up to 120 kW. In recent experiments the helicon source has produced deuterium plasmas with densities up to ~6 × 1019 m–3 measured at a location 2 m downstream from the antenna and 0.4 m from the target. Previous plasma production experiments on Proto-MPEX have generated lower density plasmas with hollow electron temperature profiles and target power deposition peaked far off axis. The latest experiments have produced flat Te profiles with a large portion of the power deposited on the target near the axis. This and other evidence points to the excitation of a helicon mode in this case.

  11. Radiation sources based on laser-plasma interactions

    NARCIS (Netherlands)

    Jaroszynski, D.A.; Bingham, R.; Brunetti, E.; Ersfeld, B.; Gallacher, J.G.; Geer, van der S.B.; Issac, R.; Jamison, S.P.; Jones, D.; Loos, de M.J.; Lyachev, A.; Pavlov, V.M.; Reitsma, A.J.W.; Saveliev, Y.M.; Vieux, G.; Wiggins, S.M.

    2006-01-01

    Plasma waves excited by intense laser beams can be harnessed to produce femtosecond duration bunches of electrons with relativistic energies. The very large electrostatic forces of plasma density wakes trailing behind an intense laser pulse provide field potentials capable of accelerating charged

  12. Two-fluid (plasma-neutral) Extended-MHD simulations of spheromak configurations in the HIT-SI experiment with PSI-Tet

    Science.gov (United States)

    Sutherland, D. A.; Hansen, C. J.; Jarboe, T. R.

    2017-10-01

    A self-consistent, two-fluid (plasma-neutral) dynamic neutral model has been implemented into the 3-D, Extended-MHD code PSI-Tet. A monatomic, hydrogenic neutral fluid reacts with a plasma fluid through elastic scattering collisions and three inelastic collision reactions: electron-impact ionization, radiative recombination, and resonant charge-exchange. Density, momentum, and energy are evolved for both the plasma and neutral species. The implemented plasma-neutral model in PSI-Tet is being used to simulate decaying spheromak configurations in the HIT-SI experimental geometry, which is being compare to two-photon absorption laser induced fluorescence measurements (TALIF) made on the HIT-SI3 experiment. TALIF is used to measure the absolute density and temperature of monatomic deuterium atoms. Neutral densities on the order of 1015 m-3 and neutral temperatures between 0.6-1.7 eV were measured towards the end of decay of spheromak configurations with initial toroidal currents between 10-12 kA. Validation results between TALIF measurements and PSI-Tet simulations with the implemented dynamic neutral model will be presented. Additionally, preliminary dynamic neutral simulations of the HIT-SI/HIT-SI3 spheromak plasmas sustained with inductive helicity injection will be presented. Lastly, potential benefits of an expansion of the two-fluid model into a multi-fluid model that includes multiple neutral species and tracking of charge states will be discussed.

  13. Flux compression generators as plasma compression power sources

    International Nuclear Information System (INIS)

    Fowler, C.M.; Caird, R.S.; Erickson, D.J.; Freeman, B.L.; Thomson, D.B.; Garn, W.B.

    1979-01-01

    A survey is made of applications where explosive-driven magnetic flux compression generators have been or can be used to directly power devices that produce dense plasmas. Representative examples are discussed that are specific to the theta pinch, the plasma gun, the dense plasma focus and the Z pinch. These examples are used to illustrate the high energy and power capabilities of explosive generators. An application employing a rocket-borne, generator-powered plasma gun emphasizes the size and weight potential of flux compression power supplies. Recent results from a local effort to drive a dense plasma focus are provided. Imploding liners ae discussed in the context of both the theta and Z pinches

  14. Plasma potentials and performance of the advanced electron cyclotron resonance ion source

    International Nuclear Information System (INIS)

    Xie, Z.Q.; Lyneis, C.M.

    1994-01-01

    The mean plasma potential was measured on the LBL advanced electron cyclotron resonance (AECR) ion source for a variety of conditions. The mean potentials for plasmas of oxygen, argon, and argon mixed with oxygen in the AECR were determined. These plasma potentials are positive with respect to the plasma chamber wall and are on the order of tens of volts. Electrons injected into the plasma by an electron gun or from an aluminum oxide wall coating with a very high secondary electron emission reduce the plasma potential as does gas mixing. A lower plasma potential in the AECR source coincides with enhanced production of high charged state ions indicating longer ion confinement times. The effect of the extra electrons from external injection or wall coatings is to lower the average plasma potential and to increase the n e τ i of the ECR plasma. With sufficient extra electrons, the need for gas mixing can be eliminated or reduced to a lower level, so the source can operate at lower neutral pressures. A reduction of the neutral pressure decreases charge exchange between ions and neutrals and enhances the production of high charge state ions. An aluminum oxide coating results in the lowest plasma potential among the three methods discussed and the best source performance

  15. Plasma jet source parameter optimisation and experiments on injection into Globus-M spherical tokamak

    International Nuclear Information System (INIS)

    Gusev, V.K.; Petrov, Yu.V.; Sakharov, N.V.; Semenov, A.A.; Voronin, A.V.

    2005-01-01

    Results of theoretical and experimental research on the plasma sources and injection of plasma and gas jet produced by the modified source into tokamak Globus-M are presented. An experimental test stand was developed for investigation of intense plasma jet generation. Optimisation of pulsed coaxial accelerator parameters by means of analytical calculations is performed with the aim of achieving the highest flow velocity at limited coaxial electrode length and discharge current. The optimal parameters of power supply to generate a plasma jet with minimal impurity contamination and maximum flow velocity were determined. A comparison of experimental and calculation results is made. Plasma jet parameters are measured, such as: impurity species content, pressure distribution across the jet, flow velocity, plasma density, etc. Experiments on the interaction of a higher kinetic energy plasma jet with the magnetic field and plasma of the Globus-M tokamak were performed. Experimental results on plasma and gas jet injection into different Globus-M discharge phases are presented and discussed. Results are presented on the investigation of plasma jet injection as the source for discharge breakdown, plasma current startup and initial density rise. (author)

  16. Field distribution of a source and energy absorption in an inhomogeneous magneto-active plasma

    International Nuclear Information System (INIS)

    Galushko, N.P.; Erokhin, N.S.; Moiseev, S.S.

    1975-01-01

    In the present paper the distribution of source fields in in a magnetoactive plasma is studied from the standpoint of the possibility of an effective SHF heating of an inhomogeneous plasma in both high (ωapproximatelyωsub(pe) and low (ωapproximatelyωsub(pi) frequency ranges, where ωsub(pe) and ωsub(pi) are the electron and ion plasma frequencies. The localization of the HF energy absorption regions in cold and hot plasma and the effect of plasma inhomogeneity and source dimensions on the absorption efficiency are investigated. The linear wave transformation in an inhomogeneous hot plasma is taken into consideration. Attention is paid to the difference between the region localization for collisional and non-collisional absorption. It has been shown that the HF energy dissipation in plasma particle collisions is localized in the region of thin jets going from the source; the radiation field has a sharp peak in this region. At the same time, non-collisional HF energy dissipation is spread over the plasma volume as a result of Cherenkov and cyclotron wave attenuation. The essential contribution to the source field from resonances due to standing wave excitation in an inhomogeneous plasma shell near the source is pointed out

  17. Source formulation for electron-impact ionization for fluid plasma simulations

    DEFF Research Database (Denmark)

    Müller, S.H.; Holland, C.; Tynan, G.R.

    2009-01-01

    The derivation of the correct functional form of source terms in plasma fluid theory is revisited. The relation between the fluid source terms and atomic physics differential cross sections is established for particle-impact ionization. It is shown that the interface between atomic and plasma phy...... electron temperature regimes in a wide variety of basic plasma physics experiments, including the trends across different gases.......The derivation of the correct functional form of source terms in plasma fluid theory is revisited. The relation between the fluid source terms and atomic physics differential cross sections is established for particle-impact ionization. It is shown that the interface between atomic and plasma...... physics is completely described by three scalar functions of the incident particle energy. These are the total cross section and the newly introduced forward momentum and energy functions, which are properties of the differential cross sections only. For electron-impact ionization, the binary...

  18. A study on tokamak fusion reactor - Numerical analyses of MHD equilibrium= and edge plasma transport in tokamak fusion reactor with divertor configurations

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Sang Hee; Lim, Ki Hang; Kang, Kyung Doo; Ryu, Ji Myung; Kim, Duk Kyu [Seoul National University, Seoul (Korea, Republic of); Cho, Soo Won [Kyungki Unviersity, Suwon (Korea, Republic of)

    1995-08-01

    In the present project for developing the numerical codes of 2-DMHD equilibrium, edge plasma transport and neutral particle transport for the tokamak plasmas, we compute the plasma equilibrium of double null type and calculate the external coil currents and the plasma parameters used for operation and control data. Also the numerical algorithm is developed to analyse the behavior of edge plasmas in poloidal and radial directions and the programming and debugging of a 2-D transport code are completed. Furthermore, a neutral particle transport code for the edge region is developed and then used for the analysis of the neutral transport phenomena giving the sources in the fluid equations, and expected to supply the input parameters for the edge plasma transport code. 34 refs., 5 tabs., 28 figs. (author)

  19. kHz femtosecond laser-plasma hard X-ray and fast ion source

    International Nuclear Information System (INIS)

    Thoss, A.; Korn, G.; Stiel, H.; Voigt, U.; Elsaesser, T.; Richardson, M.C.; Siders, C.W.; Faubel, M.

    2002-01-01

    We describe the first demonstration of a new stable, kHz femtosecond laser-plasma source of hard x-ray continuum and K α emission using a thin liquid metallic jet target. kHz femtosecond x-ray sources will find many applications in time-resolved x-ray diffraction and microscopy studies. As high intensity lasers become more compact and operate at increasingly high repetition-rates, they require a target configuration that is both repeatable from shot-to-shot and is debris-free. We have solved this requirement with the use of a fine (10-30 μm diameter) liquid metal jet target that provides a pristine, unperturbed filament surface at rates >100 kHz. A number of liquid metal targets are considered. We will show hard x-ray spectra recorded from liquid Ga targets that show the generation of the 9.3 keV and 10.3 keV, K α and K β lines superimposed on a multi-keV Bremsstrahlung continuum. This source was generated by a 50fs duration, 1 kHz, 2W, high intensity Ti:Sapphire laser. We will discuss the extension of this source to higher powers and higher repetition rates, providing harder x-ray emission, with the incorporation of pulse-shaping and other techniques to enhance the x-ray conversion efficiency. Using the same liquid target technology, we have also demonstrated the generation of forward-going sub-MeV protons from a 10 μm liquid water target at 1 kHz repetition rates. kHz sources of high energy ions will find many applications in time-resolved particle interaction studies, as well as lead to the efficient generation of short-lived isotopes for use in nuclear medicine and other applications. The protons were detected with CR-39 track detectors both in the forward and backward directions up to energies of ∼500 keV. As the intensity of compact high repetition-rate lasers sources increase, we can expect improvements in the energy, conversion efficiency and directionality to occur. The impact of these developments on a number of fields will be discussed. As compact

  20. Plasma ignition and steady state simulations of the Linac4 H$^{-}$ ion source

    CERN Document Server

    Mattei, S; Yasumoto, M; Hatayama, A; Lettry, J; Grudiev, A

    2014-01-01

    The RF heating of the plasma in the Linac4 H- ion source has been simulated using an Particle-in-Cell Monte Carlo Collision method (PIC-MCC). This model is applied to investigate the plasma formation starting from an initial low electron density of 1012 m-3 and its stabilization at 1018 m-3. The plasma discharge at low electron density is driven by the capacitive coupling with the electric field generated by the antenna, and as the electron density increases the capacitive electric field is shielded by the plasma and induction drives the plasma heating process. Plasma properties such as e-/ion densities and energies, sheath formation and shielding effect are presented and provide insight to the plasma properties of the hydrogen plasma.

  1. Development of a 1-m plasma source for heavy ion beam charge neutralization

    Science.gov (United States)

    Efthimion, Philip C.; Gilson, Erik P.; Grisham, Larry; Davidson, Ronald C.; Yu, Simon; Waldron, William; Grant Logan, B.

    2005-05-01

    Highly ionized plasmas are being employed as a medium for charge neutralizing heavy ion beams in order to focus to a small spot size. Calculations suggest that plasma at a density of 1-100 times the ion beam density and at a length ˜0.1-1 m would be suitable for achieving a high level of charge neutralization. A radio frequency (RF) source was constructed at the Princeton Plasma Physics Laboratory (PPPL) in support of the joint Neutralized Transport Experiment (NTX) at the Lawrence Berkeley National Laboratory (LBNL) to study ion beam neutralization. Pulsing the source enabled operation at pressures ˜10 -6 Torr with plasma densities of 10 11 cm -3. Near 100% ionization was achieved. The plasma was 10 cm in length, but future experiments require a source 1 m long. The RF source does not easily scale to the length. Consequently, large-volume plasma sources based upon ferroelectric ceramics are being considered. These sources have the advantage of being able to increase the length of the plasma and operate at low neutral pressures. The source will utilize the ferroelectric ceramic BaTiO 3 to form metal plasma. A 1 m long section of the drift tube inner surface of NTX will be covered with ceramic. A high voltage (˜1-5 kV) is applied between the drift tube and the front surface of the ceramic by placing a wire grid on the front surface. Plasma densities of 10 12 cm -3 and neutral pressures ˜10 -6 Torr are expected. A test stand to produce 20 cm long plasma is being constructed and will be tested before a 1 m long source is developed.

  2. Development of a 1-m plasma source for heavy ion beam charge neutralization

    International Nuclear Information System (INIS)

    Efthimion, Philip C.; Gilson, Erik P.; Grisham, Larry; Davidson, Ronald C.; Yu, Simon; Waldron, William; Grant Logan, B.

    2005-01-01

    Highly ionized plasmas are being employed as a medium for charge neutralizing heavy ion beams in order to focus to a small spot size. Calculations suggest that plasma at a density of 1-100 times the ion beam density and at a length ∼0.1-1 m would be suitable for achieving a high level of charge neutralization. A radio frequency (RF) source was constructed at the Princeton Plasma Physics Laboratory (PPPL) in support of the joint Neutralized Transport Experiment (NTX) at the Lawrence Berkeley National Laboratory (LBNL) to study ion beam neutralization. Pulsing the source enabled operation at pressures ∼10 -6 Torr with plasma densities of 10 11 cm -3 . Near 100% ionization was achieved. The plasma was 10 cm in length, but future experiments require a source 1 m long. The RF source does not easily scale to the length. Consequently, large-volume plasma sources based upon ferroelectric ceramics are being considered. These sources have the advantage of being able to increase the length of the plasma and operate at low neutral pressures. The source will utilize the ferroelectric ceramic BaTiO 3 to form metal plasma. A 1 m long section of the drift tube inner surface of NTX will be covered with ceramic. A high voltage (∼1-5 kV) is applied between the drift tube and the front surface of the ceramic by placing a wire grid on the front surface. Plasma densities of 10 12 cm -3 and neutral pressures ∼10 -6 Torr are expected. A test stand to produce 20 cm long plasma is being constructed and will be tested before a 1 m long source is developed

  3. Plasma Instability Based Compact Coherent Terahertz Radiation Sources

    National Research Council Canada - National Science Library

    Bakshi, P

    2004-01-01

    .... These are in good agreement with experiments carried out at TU Vienna. A sharp emission line was obtained in the most recent structure, suggesting that we are close to the onset of plasma instability...

  4. QSARs for Plasma Protein Binding: Source Data and Predictions

    Data.gov (United States)

    U.S. Environmental Protection Agency — The dataset has all of the information used to create and evaluate 3 independent QSAR models for the fraction of a chemical unbound by plasma protein (Fub) for...

  5. Plasma X-ray sources powered by megajoule magnetocumulative generators

    Energy Technology Data Exchange (ETDEWEB)

    Popkov, N F; Averchenkov, V Ya; Pikar` , A S; Ryaslov, E A; Kargin, V I; Lazarev, S A; Borodkov, V V; Nazarenko, S T; Makartsev, G F [All-Russian Research Inst. of Experimental Physics, Sarov (Russian Federation). Russian Federal Nuclear Center

    1997-12-31

    Experiments using magnetocumulative generators (MCGs) were performed to power three different types of high-energy-density plasma discharges suitable for intense x-ray generation. These included the H-pressed discharge, the capillary z-pinch, and the {theta}-pinch. The MCGs were operated both with and without plasma opening switches. The characteristic currents were approximately 10 MA and characteristic time scales approximately 1 {mu}s. (author). 7 figs., 3 refs.

  6. A 14-MeV beam-plasma neutron source for materials testing

    International Nuclear Information System (INIS)

    Futch, A.H.; Coensgen, F.H.; Damm, C.C.; Molvik, A.W.

    1989-01-01

    The design and performance of 14-MeV beam-plasma neutron sources for accelerated testing of fusion reactor materials are described. Continuous production of 14-MeV neutron fluxes in the range of 5 to 10 MW/m 2 at the plasma surface are produced by D-T reactions in a two-component plasma. In the present designs, 14-MeV neutrons result from collisions of energetic deuterium ions created by transverse injection of 150-keV deuterium atoms on a fully ionized tritium target plasma. The beam energy, which deposited at the center of the tritium column, is transferred to the warm plasma by electron drag, which flows axially to the end regions. Neutral gas at high pressure absorbs the energy in the tritium plasma and transfers the heat to the walls of the vacuum vessel. The plasma parameters of the neutron source, in dimensionless units, have been achieved in the 2XIIB high-β plasma. The larger magnetic field of the present design permits scaling to the higher energy and density of the neutron source design. In the extrapolation, care has been taken to preserve the scaling and plasma attributes that contributed to equilibrium, magnetohydrodynamic (MHD) stability, and microstability in 2XIIB. The performance and scaling characteristics are described for several designs chosen to enhance the thermal isolation of the two-component plasmas. 11 refs., 3 figs., 3 tabs

  7. Radiation from a pulsed dipole source in a moving magnetized plasma

    International Nuclear Information System (INIS)

    Gavrilenko, V. G.; Petrov, E. Yu.; Pikulin, V. D.; Sutyagina, D. A.

    2006-01-01

    The problem of radiation from a pulsed dipole source in a moving magnetized plasma described by a diagonal permittivity tensor is considered. An exact solution describing the spatiotemporal behavior of the excited electromagnetic field is obtained. The shape of an electromagnetic pulse that is generated by the source and propagates at different angles to both the direction of the external magnetic field and the direction of plasma motion is investigated. It is found that even nonrelativistic motion of the plasma medium can substantially influence the parameters of radiation from prescribed unsteady sources

  8. Determination of plasma spot current and arc discharge plasma current on the system of plasma cathode electron sources using Rogowski coil technique

    International Nuclear Information System (INIS)

    Wirjoadi; Bambang Siswanto; Lely Susita RM; Agus Purwadi; Sudjatmoko

    2015-01-01

    It has been done the function test experiments of ignitor electrode system and the plasma generator electrode system to determine the current spot plasma and arc discharge plasma current with Rogowski coil technique. Ignitor electrode system that gets power supply from IDPS system can generate the plasma spot current of 11.68 ampere to the pulse width of about 33 μs, this value is greater than the design probably because of electronic components used in the IDPS system was not as planned. For the plasma generator electrode system that gets power from ADPS system capable of producing an arc discharge plasma current around 103.15 amperes with a pulse width of about 96 μs, and this value as planned. Based on the value of the arc discharge plasma current can be determined plasma electron density, which is about 10.12 10"1"9 electrons/m"3, and with this electron density value, an ignitor electrode system and a plasma generator system is quite good if used as a plasma cathode electron source system. (author)

  9. Development of zeolite ion source for beam probe measurements of high temperature plasma

    International Nuclear Information System (INIS)

    Ohshima, Shinsuke; Fujisawa, Akihide; Shimizu, Akihiro; Nakano, Haruhisa

    2005-10-01

    A zeolite ion source has been developed for plasma diagnostics. Extracted beam current is increased by a factor of ∼10 after redesigning the ion source structure and improving the method to make emitter material (zeolite). The paper introduces an experiment on making desirable ion emitter, together with properties of the newly developed ion source. (author)

  10. Permanent magnet electron cyclotron resonance plasma source with remote window

    International Nuclear Information System (INIS)

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

    1995-01-01

    An electron cyclotron resonance (ECR) plasma has been used in conjunction with a solid metal sputter target for Cu deposition over 200 mm diameters. The goal is to develop a deposition system and process suitable for filling submicron, high-aspect ratio ULSI features. The system uses a permanent magnet for creation of the magnetic field necessary for ECR, and is significantly more compact than systems equipped with electromagnets. A custom launcher design allows remote microwave injection with the microwave entrance window shielded from the copper flux. When microwaves are introduced at an angle with respect to the plasma, high electron densities can be produced with a plasma frequency significantly greater than the electron cyclotron frequency. Copper deposition rates of 1000 A/min have been achieved

  11. Shaping the electron beams with submicrosecond pulse duration in sources and electron accelerators with plasma emitters

    CERN Document Server

    Gushenets, V I

    2001-01-01

    One studies the techniques in use to shape submicrosecond electron beams and the physical processes associated with extraction of electrons from plasma in plasma emitters. Plasma emitter base sources and accelerators enable to generate pulse beams with currents varying from tens of amperes up to 10 sup 3 A, with current densities up to several amperes per a square centimeter, with pulse duration constituting hundreds of nanoseconds and with high frequencies of repetition

  12. Abnormally large energy spread of electron beams extracted from plasma sources

    Energy Technology Data Exchange (ETDEWEB)

    Winter, H [Technische Univ., Vienna (Austria). Inst. fuer Allgemeine Physik

    1976-07-01

    Intense electron beams extracted from DUOPLASMATRON-plasma cathodes show a high degree of modulation in intensity and an abnormally large energy spread; these facts cannot be explained simply by the temperature of the plasma electrons and the discharge structure. However, an analysis of the discharge stability behaviour and the interaction of source- and extracted beam-plasma leads to an explanation for the observed effects.

  13. Formation of Nitrogen Oxides in an Apokamp-Type Plasma Source

    Science.gov (United States)

    Sosnin, É. A.; Goltsova, P. A.; Panarin, V. A.; Skakun, V. S.; Tarasenko, V. F.; Didenko, M. V.

    2017-08-01

    Using optical and chemical processes, the composition of the products of decay of the atmospheric-pressure non-equilibrium plasma is determined in a pulsed, high-voltage discharge in the modes of apokampic and corona discharges. It is shown that the products of decay primarily contain nitrogen oxides NO x, and in the mode of the corona discharge - ozone. Potential applications of this source of plasma are discussed with respect to plasma processing of the seeds of agricultural crops.

  14. Characterization of an atmospheric pressure air plasma source for polymer surface modification

    Science.gov (United States)

    Yang, Shujun; Tang, Jiansheng

    2013-10-01

    An atmospheric pressure air plasma source was generated through dielectric barrier discharge (DBD). It was used to modify polyethyleneterephthalate (PET) surfaces with very high throughput. An equivalent circuit model was used to calculate the peak average electron density. The emission spectrum from the plasma was taken and the main peaks in the spectrum were identified. The ozone density in the down plasma region was estimated by Absorption Spectroscopy. NSF and ARC-ODU

  15. An Open Source Computational Framework for Uncertainty Quantification of Plasma Chemistry Models

    OpenAIRE

    Zaheri Sarabi, Shadi

    2017-01-01

    The current thesis deals with the development of a computational framework for performing plasma chemistry simulations and their uncertainty quantification analysis by suitably combining and extending existing open source computational tools. A plasma chemistry solver is implemented in the OpenFOAM C++ solver suite. The OpenFOAM plasma chemistry application solves the species conservation equations and the electron energy equation by accounting suitably for various production and loss terms b...

  16. Ion acoustic double layers in the presence of plasma source

    International Nuclear Information System (INIS)

    Okuda, H.; Ashour-Abdalla, M.

    1982-01-01

    Steady-state plasma turbulence and the formation of negative potential spikes and double layers in the presence of ion acoustic instabilities have been studied by means of one-dimensional particle simulations in which the velocities of a small fraction of electrons are replaced by the initial drifting Maxwellian at a constant rate. A steady state is found where negative potential spikes appear randomly in space and time giving rise to an anomalous resistivity much greater than previously found. Comparisons of the simulation results with laboratory and space plasmas are discussed

  17. Injection of auxiliary electrons for increasing the plasma density in highly charged and high intensity ion sources

    Energy Technology Data Exchange (ETDEWEB)

    Odorici, F., E-mail: fabrizio.odorici@bo.infn.it; Malferrari, L.; Montanari, A. [INFN—Bologna, Viale B. Pichat, 6/2, 40127 Bologna (Italy); Rizzoli, R. [INFN—Bologna, Viale B. Pichat, 6/2, 40127 Bologna (Italy); CNR–Istituto per la Microelettronica ed i Microsistemi, Via Gobetti 101, 40129 Bologna (Italy); Mascali, D.; Castro, G.; Celona, L.; Gammino, S.; Neri, L. [INFN–Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy)

    2016-02-15

    Different electron guns based on cold- or hot-cathode technologies have been developed since 2009 at INFN for operating within ECR plasma chambers as sources of auxiliary electrons, with the aim of boosting the source performances by means of a higher plasma lifetime and density. Their application to microwave discharge ion sources, where plasma is not confined, has required an improvement of the gun design, in order to “screen” the cathode from the plasma particles. Experimental tests carried out on a plasma reactor show a boost of the plasma density, ranging from 10% to 90% when the electron guns are used, as explained by plasma diffusion models.

  18. Injection of auxiliary electrons for increasing the plasma density in highly charged and high intensity ion sources.

    Science.gov (United States)

    Odorici, F; Malferrari, L; Montanari, A; Rizzoli, R; Mascali, D; Castro, G; Celona, L; Gammino, S; Neri, L

    2016-02-01

    Different electron guns based on cold- or hot-cathode technologies have been developed since 2009 at INFN for operating within ECR plasma chambers as sources of auxiliary electrons, with the aim of boosting the source performances by means of a higher plasma lifetime and density. Their application to microwave discharge ion sources, where plasma is not confined, has required an improvement of the gun design, in order to "screen" the cathode from the plasma particles. Experimental tests carried out on a plasma reactor show a boost of the plasma density, ranging from 10% to 90% when the electron guns are used, as explained by plasma diffusion models.

  19. Electron cyclotron resonance plasmas and electron cyclotron resonance ion sources: Physics and technology (invited)

    International Nuclear Information System (INIS)

    Girard, A.; Hitz, D.; Melin, G.; Serebrennikov, K.

    2004-01-01

    Electron cyclotron resonance (ECR) ion sources are scientific instruments particularly useful for physics: they are extensively used in atomic, nuclear, and high energy physics, for the production of multicharged beams. Moreover, these sources are also of fundamental interest for plasma physics, because of the very particular properties of the ECR plasma. This article describes the state of the art on the physics of the ECR plasma related to multiply charged ion sources. In Sec. I, we describe the general aspects of ECR ion sources. Physics related to the electrons is presented in Sec. II: we discuss there the problems of heating and confinement. In Sec. III, the problem of ion production and confinement is presented. A numerical code is presented, and some particular and important effects, specific to ECR ion sources, are shown in Sec. IV. Eventually, in Sec. V, technological aspects of ECR are presented and different types of sources are shown

  20. An open-source framework for analyzing N-electron dynamics. II. Hybrid density functional theory/configuration interaction methodology.

    Science.gov (United States)

    Hermann, Gunter; Pohl, Vincent; Tremblay, Jean Christophe

    2017-10-30

    In this contribution, we extend our framework for analyzing and visualizing correlated many-electron dynamics to non-variational, highly scalable electronic structure method. Specifically, an explicitly time-dependent electronic wave packet is written as a linear combination of N-electron wave functions at the configuration interaction singles (CIS) level, which are obtained from a reference time-dependent density functional theory (TDDFT) calculation. The procedure is implemented in the open-source Python program detCI@ORBKIT, which extends the capabilities of our recently published post-processing toolbox (Hermann et al., J. Comput. Chem. 2016, 37, 1511). From the output of standard quantum chemistry packages using atom-centered Gaussian-type basis functions, the framework exploits the multideterminental structure of the hybrid TDDFT/CIS wave packet to compute fundamental one-electron quantities such as difference electronic densities, transient electronic flux densities, and transition dipole moments. The hybrid scheme is benchmarked against wave function data for the laser-driven state selective excitation in LiH. It is shown that all features of the electron dynamics are in good quantitative agreement with the higher-level method provided a judicious choice of functional is made. Broadband excitation of a medium-sized organic chromophore further demonstrates the scalability of the method. In addition, the time-dependent flux densities unravel the mechanistic details of the simulated charge migration process at a glance. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  1. Stationary plasma source of heavy ions for imitating research at the separator

    International Nuclear Information System (INIS)

    Yuferov, V.B.; Sharyj, S.V.; Seroshtanov, V.A.

    2008-01-01

    The imitation gas mix choice for experimenting on the demonstration imitation separator have been grounded. The construction of plasma source is changed. The research of operating conditions and contrastive analysis of received characteristics have been carry out

  2. Facility Effects on a Helicon Plasma Source with a Magnetic Nozzle

    Data.gov (United States)

    National Aeronautics and Space Administration — Proposed here is an analysis of facility effects on a small helicon plasma source with a magnetic nozzle. Backpressure effects will first be recorded and analyzed....

  3. ECR plasma source in a flaring magnetic field

    International Nuclear Information System (INIS)

    Meis, C.; Compant La Fontaine, A.; Louvet, P.

    1992-01-01

    The propagation and absorption of an electromagnetic wave, near the electron cyclotron zone, of a cold plasma (T e ∼ 1-5 eV) confined in a flaring magnetic field is studied. The case of both extraordinary and ordinary modes has been considered. Temperature effects and electron-neutral collisions have been taken account in the dielectric tensor

  4. Air spark-like plasma source for antimicrobial NOx generation

    International Nuclear Information System (INIS)

    Pavlovich, M J; Galleher, C; Curtis, B; Clark, D S; Graves, D B; Ono, T; Machala, Z

    2014-01-01

    We demonstrate and analyse the generation of nitrogen oxides and their antimicrobial efficacy using atmospheric air spark-like plasmas. Spark-like discharges in air in a 1 L confined volume are shown to generate NO x at an initial rate of about 1.5  ×  10 16 NO x molecules/J dissipated in the plasma. Such a discharge operating in this confined volume generates on the order of 6000 ppm NO x in 10 min. Around 90% of the NO x is in the form of NO 2 after several minutes of operation in the confined volume, suggesting that NO 2 is the dominant antimicrobial component. The strong antimicrobial action of the NO x mixture after several minutes of plasma operation is demonstrated by measuring rates of E. coli disinfection on surfaces and in water exposed to the NO x mixture. Some possible applications of plasma generation of NO x (perhaps followed by dissolution in water) include disinfection of surfaces, skin or wound antisepsis, and sterilization of medical instruments at or near room temperature. (paper)

  5. Nuclear Malaysia Plasma Focus Device as a X-ray Source For Radiography Applications

    International Nuclear Information System (INIS)

    Rokiah Mohd Sabri; Abdul Halim Baijan; Siti Aiasah Hashim; Mohd Rizal Mohd Chulan; Wah, L.K.; Mukhlis Mokhtar; Azaman Ahmad; Rosli Che Ros

    2013-01-01

    A 3.375 kJ plasma focus is designed to operate at 13.5 kV for the purpose of studying x-ray source for radiography in Argon discharge. X-rays is detected by using x-ray film from the mammography radiographic plate. The feasibility of the plasma focus as a high intensity flash x-ray source for good contrast in radiography image is presented. (author)

  6. Characterisation of edge turbulence in relation to edge magnetic field configuration in L-mode plasmas in the Mega Amp Spherical Tokamak.

    Science.gov (United States)

    Dewhurst, J.; Hnat, B.; Dudson, B.; Dendy, R. O.; Counsell, G. F.; Kirk, A.

    2007-12-01

    Almost all astrophysical and magnetically confined fusion plasmas are turbulent. Here, we examine ion saturation current (Isat) measurements of edge plasma turbulence for three MAST L-mode plasmas that differ primarily in their edge magnetic field configurations. First, absolute moments of the coarse grained data are examined to obtain accurate values of scaling exponents. The dual scaling behaviour is identified in all samples, with the temporal scale τ ≍ 40-60 μs separating the two regimes. Strong universality is then identified in the functional form of the probability density function (PDF) for Isat fluctuations, which is well approximated by the Fréchet distribution on temporal scales τ ≤ 40μs. For temporal scales τ > 40μs, the PDFs appear to converge to the Gumbel distribution, which has been previously identified as a universal feature of many other complex phenomena. The optimal fitting parameters k=1.15 for Fréchet and a=1.35 for Gumbel provide a simple quantitative characterisation of the full spectrum of fluctuations. We conclude that, to good approximation, the properties of the edge turbulence are independent of the edge magnetic field configuration.

  7. Two new planar coil designs for a high pressure radio frequency plasma source

    Science.gov (United States)

    Munsat, T.; Hooke, W. M.; Bozeman, S. P.; Washburn, S.

    1995-04-01

    Two planar coil designs for a high pressure rf plasma source are investigated using spectroscopic techniques and circuit analysis. In an Ar plasma a truncated version of the commonly used ``spiral'' coil is found to produce improvements in peak electron density of 20% over the full version. A coil with figure-8 geometry is found to move plasma inhomogeneities off of center and produce electron densities comparable to the spiral coils. Both of these characteristics are advantageous in industrial applications. Coil design characteristics for favorable power coupling are also determined, including the necessity of closed hydrodynamic plasma loops and the drawback of closely situated antiparallel coil currents.

  8. Performance of the CERN plasma lens in laboratory and beam tests at the Antiproton Source

    International Nuclear Information System (INIS)

    Kowalewicz, R.; Lubrano di Scampamorte, M.; Milner, S.; Pedersen, F.; Riege, H.; Christiansen, J.; Frank, K.; Stetter, M.; Tkotz, R.; Boggasch, E.

    1991-01-01

    The CERN plasma lens is based on a dynamic z-pinch which creates during 500 ns a cylindrical plasma current conductor of 290 mm length and 38 to 45 mm diameter. The lens is designed for pulsed pinched currents of 400 kA and magnetic field gradients of 200 T/m produced with stored energies of 56 kJ. Life tests of different lens components were carried through at a repetition rate of 4.8 s/pulse. The results of the first beam tests of the plasma lens at the CERN antiproton source are very encouraging in view of other potential plasma lens applications

  9. Ion source plasma parameters measurement based on Langmuir probe with commercial frequency sweep

    International Nuclear Information System (INIS)

    Xie, Y.H.; Hu, C.D.; Liu, S.; Shong, S.H.; Jiang, C.C.; Liu, Z.M.

    2010-01-01

    Langmuir probe is one of the main diagnostic tools to measure the plasma parameters in the ion source. In this article, the commercial frequency power, which is sine wave of 50 Hz, was supplied on the Langmuir probe to measure the plasma parameters. The best feature of this probe sweep voltage is that it does not need extra design. The probe I-V characteristic curve can be got in less than 5 ms and the plasma parameters, the electron temperature and the electron density, varying with the time can be got in one plasma discharge of 400 ms.

  10. X-ray radiation source based on a plasma filled diode

    Energy Technology Data Exchange (ETDEWEB)

    Popkov, N F; Kargin, V I; Ryaslov, E A; Pikar, A S [All-Russian Research Inst. of Experimental Physics, Sarov (Russian Federation). Russian Federal Nuclear Center

    1997-12-31

    The results are given of studies on a plasma X-ray source providing 2.5 krad of radiation dose per pulse over an area of 100 cm{sup 2} in the quantum energy range between 20 and 500 keV. The pulse duration was 100 ns. The spectral radiation distribution was obtained under various operating conditions of plasma and diode. A Marx generator served as the starting power source of 120 kJ with a discharge time of T/4=10{sup -6} s. A short electromagnetic pulse (10{sup -7} s) was shaped using plasma erosion opening switches. (author). 5 figs., 4 refs.

  11. Microwave plasma source for neutral-beam injection systems. Quarterly technical progress report

    International Nuclear Information System (INIS)

    1981-01-01

    The overall program is described and the technical and programmatic reasons for the decision to pursue both the RFI and ECH sources into the current hydrogen test stage is discussed. We consider the general characteristics of plasma sources in the parameter regime of interest for neutral beam applications. The operatonal characteristics, advantages and potential problems of RFI and ECH sources are discussed. In these latter two sections we rely heavily on experience derived from developing RFI and ECH ion engine sources for NASA

  12. Impurities, temperature, and density in a miniature electrostatic plasma and current source

    International Nuclear Information System (INIS)

    Den Hartog, D.J.; Craig, D.J.; Fiksel, G.; Sarff, J.S.

    1996-10-01

    We have spectroscopically investigated the Sterling Scientific miniature electrostatic plasma source-a plasma gun. This gun is a clean source of high density (10 19 - 10 20 m -3 ), low temperature (5 - 15 eV) plasma. A key result of our investigation is that molybdenum from the gun electrodes is largely trapped in the internal gun discharge; only a small amount escapes in the plasma flowing out of the gun. In addition, the gun plasma parameters actually improve (even lower impurity contamination and higher ion temperature) when up to 1 kA of electron current is extracted from the gun via the application of an external bias. This improvement occurs because the internal gun anode no longer acts as the current return for the internal gun discharge. The gun plasma is a virtual plasma electrode capable of sourcing an electron emission current density of 1 kA/cm 2 . The high emission current, small size (3 - 4 cm diameter), and low impurity generation make this gun attractive for a variety of fusion and plasma technology applications

  13. Uses of dense magnetized plasmas as neutron sources

    International Nuclear Information System (INIS)

    Gonzalez, Jose Hector

    2004-01-01

    In this work, a lumped parameter model for Plasma Focus is presented.A fast running computer code was developed, specially focused to the calculation of the neutron production in Deuterium-filled devices.This code is suitable to parameters optimization at the conceptual engineering stage.The kinematics of the current sheet is represented by a plane, 2D snowplow model.It is complemented with sensible estimations for the current sheet characteristics (density n and temperature T).After the radial collapse, a one fluid MHD model with velocity profiles for the particles trapped inside the pinch is proposed.Then, assuming thermal equilibrium in the plasma, the neutron production by termofusion can be estimated.The dynamics equations are coupled with the electrical circuit. A computer code in FORTRAN language was programmed to solve this set of equations.A powerful numerical integrator for first order differential equations is used, and the code can perform an estimation of the neutron production very quickly.The resulting neutron yield and dynamics predictions have been compared against experimental results of Plasma Focus devices from all around the world, for different geometric and energetic conditions.The effective parameters of the model were validated using those experimental measurements. The presented model ultimately calculates the neutron production given the geometric and energetic parameters, and the filling pressure

  14. Ion beam extraction from a matrix ECR plasma source by discrete ion-focusing effect

    DEFF Research Database (Denmark)

    Stamate, Eugen; Draghici, Mihai

    2010-01-01

    -ECR plasma source [3] with transversal magnetic filter for electron temperature control. 12 ECR plasma cells are placed 7.5 cm apart on the top of a cubic chamber 40x40x40 cm3. Each cell can be controlled independently by tuning the injected microwave power. The discharge is operated at pressures below 1 m......Positive or negative ion beams extracted from plasma are used in a large variety of surface functionalization techniques such as implantation, etching, surface activation, passivation or oxidation. Of particular importance is the surface treatment of materials sensitive to direct plasma exposure...... due to high heath fluxes, the controllability of the ion incidence angle, and charge accumulation when treating insulating materials. Despite of a large variety of plasma sources available for ion beam extraction, there is a clear need for new extraction mechanisms that can make available ion beams...

  15. Characteristics of the Plasma Source for Ground Ionosphere Simulation Surveyed by Disk-Type Langmuir Probe

    Science.gov (United States)

    Ryu, Kwangsun; Lee, Junchan; Kim, Songoo; Chung, Taejin; Shin, Goo-Hwan; Cha, Wonho; Min, Kyoungwook; Kim, Vitaly P.

    2017-12-01

    A space plasma facility has been operated with a back-diffusion-type plasma source installed in a mid-sized vacuum chamber with a diameter of 1.5 m located in Satellite Technology Research Center (SaTReC), Korea Advanced Institute of Science and Technology (KAIST). To generate plasma with a temperature and density similar to the ionospheric plasma, nickel wires coated with carbonate solution were used as filaments that emit thermal electrons, and the accelerated thermal electrons emitted from the heated wires collide with the neutral gas to form plasma inside the chamber. By using a disk-type Langmuir probe installed inside the vacuum chamber, the generation of plasma similar to the space environment was validated. The characteristics of the plasma according to the grid and plate anode voltages were investigated. The grid voltage of the plasma source is realized as a suitable parameter for manipulating the electron density, while the plate voltage is suitable for adjusting the electron temperature. A simple physical model based on the collision cross-section of electron impact on nitrogen molecule was established to explain the plasma generation mechanism.

  16. Plasma particle sources due to interactions with neutrals in a turbulent scrape-off layer of a toroidally confined plasma

    Science.gov (United States)

    Thrysøe, A. S.; Løiten, M.; Madsen, J.; Naulin, V.; Nielsen, A. H.; Rasmussen, J. Juul

    2018-03-01

    The conditions in the edge and scrape-off layer (SOL) of magnetically confined plasmas determine the overall performance of the device, and it is of great importance to study and understand the mechanics that drive transport in those regions. If a significant amount of neutral molecules and atoms is present in the edge and SOL regions, those will influence the plasma parameters and thus the plasma confinement. In this paper, it is displayed how neutrals, described by a fluid model, introduce source terms in a plasma drift-fluid model due to inelastic collisions. The resulting source terms are included in a four-field drift-fluid model, and it is shown how an increasing neutral particle density in the edge and SOL regions influences the plasma particle transport across the last-closed-flux-surface. It is found that an appropriate gas puffing rate allows for the edge density in the simulation to be self-consistently maintained due to ionization of neutrals in the confined region.

  17. Magnetic configuration effects on plasma transport under Neutral Beam Injection at TJ-II (Simulation); Efectos de Configuracion Magnetica en el Transporte de Plasma durante la Inyeccion de Haces Neutros en el TJ-II (Simulacion)

    Energy Technology Data Exchange (ETDEWEB)

    Guasp, J.; Fuentes, C.; Liniers, M.

    2001-07-01

    A systematic analysis of magnetic configurations (27 in total), using a Transport model including impurity dynamics and sputtering effects has been done. For small size configurations or those close to rational t values there is radioactive collapse, independently of the external gas puffing (GP) strategy chosen. The reason is the insufficiency of observed power, either by the high shine through losses due to their low radii, or by the increase of fast ion orbit losses near the resonances. For the majority of configurations without collapse, fast ion orbit losses for CO injection (going in the same direction than the toroidal magnetic field) are higher, and in consequence the power absorption and the plasma {beta} achieved are laser, than for the opposite direction. Nevertheless in the region placed just above the main resonances (1/3 and 1/2 per period) this situation reverses. The reasons have been analysed and explained at previous studies. A consequence of this fact is that the optima of confinement for the Counter case are shifted towards higher t values than the CO one, with higher plasma {beta}, except near the resonances. As usual the balanced case is in between. The optima achieving stationary state are very close (and often are coincident) with those lacking that restriction. The best configuration (highest average {beta}) for balanced injection, with <{beta}>=1.1% and central value 3.2%, although in this region the results are rather insensitive to configuration and GP strategy. The configurations placed around the 100{sub 4}4 would need also the lowest power entering the torus in order to avoid collapse and to achieve an acceptable NBI absorption level. (Author) 12 refs.

  18. Spectral lines and characteristic of temporal variations in photoionized plasmas induced with laser-produced plasma extreme ultraviolet source

    Science.gov (United States)

    Saber, I.; Bartnik, A.; Wachulak, P.; Skrzeczanowski, W.; Jarocki, R.; Fiedorowicz, H.

    2017-11-01

    Spectral lines for Kr/Ne/H2 photoionized plasma in the ultraviolet and visible (UV/Vis) wavelength ranges have been created using a laser-produced plasma (LPP) EUV source. The source is based on a double-stream gas puff target irradiated with a commercial Nd:YAG laser. The laser pulses were focused onto a gas stream, injected into a vacuum chamber synchronously with the EUV pulses. Spectral lines from photoionization in neutral Kr/Ne/H2 and up to few charged states were observed. The intense emission lines were associated with the Kr transition lines. Experimental and theoretical investigations on intensity variations for some ionic lines are presented. A decrease in the intensity with the delay time between the laser pulse and the spectrum acquisition was revealed. Electron temperature and electron density in the photoionized plasma have been estimated from the characteristic emission lines. Temperature was obtained using Boltzmann plot method, assuming that the population density of atoms and ions are considered in a local thermodynamic equilibrium (LTE). Electron density was calculated from the Stark broadening profile. The temporal evaluation of the plasma and the way of optimizing the radiation intensity of LPP EUV sources is discussed.

  19. The study of 3s3p4 configuration in the P-Sequence, Co X III - Ni X IV, by laser-produced plasmas

    International Nuclear Information System (INIS)

    Borges, F.O.; Cavalcanti, G.H.; Farias, E.E.; Trigueiros, A.G.

    2007-01-01

    Wavelengths from radiation of plasmas produced by a Nd:YAG/glass laser focused on target of Co and Ni have been recorded photographically in the region 240-600 A with a 3m normal incidence spectrograph. For this sequence (Co X III and Ni X IV) we have identified 13 new lines belonging to the array 3s 2 3p 3 -3s3p 4 and derived 7 new levels for the 3s3p 4 configuration. The classification was established by comparison of the relative intensities for the lines along the isoelectronic sequence, extrapolation, and Hartree-Fock calculation. (author)

  20. The plasma focus as a large fluence neutron source

    International Nuclear Information System (INIS)

    Zucker, O.; Bostick, W.; Long, J.; Luce, J.; Sahlin, H.

    1977-01-01

    A continuously operated, 1 pps, dense-plasma-focus device capable of delivering a minimum of 10 15 neutrons per pulse for material testing purposes is described. With I 5 scaling, predicted from analysis of existing machines, yields of 10 16 -10 17 neutrons per pulse are postulated. The average power consumption, which has become a major issue as a result of the energy crisis is shown to be highly favorable. A novel approach to the capacitor bank and switch design allowing repetitive operation is discussed. (Auth.)

  1. Characterization of the plasma-switch interaction in the LBL HIF ion source

    International Nuclear Information System (INIS)

    Hewett, D.W.; Rutkowski, H.L.

    1990-01-01

    A new way to characterize the performance of the LBL HIF ion source has been found. In the LBL source, ions are drawn from an arc-generated plasma reservoir in which the electrons are confined by a negative-biased ''switch'' mesh. Stagnation of the plasma is prevented by absorption of the excess ion flow on this mesh. The ion beam is generated by an external negative voltage that provides Child-Langmuir extraction of the ions through the switch mesh. We elucidate the physics requirements of the source and deduce switch mesh parameters needed for successful operation. 2 refs., 2 figs

  2. Observation of inward and outward particle convection in the core of electron cyclotron heated and current driven plasmas in the Tokamak a Configuration Variable

    International Nuclear Information System (INIS)

    Furno, I.; Weisen, H.

    2003-01-01

    In the Tokamak a Configuration Variable [F. Hofmann, J.B. Lister, M. Anton et al., Plasma Phys. Controlled Fusion 36, B277 (1994)], inward or outward convection in the core of electron cyclotron heated and current driven plasmas is observed, depending on discharge conditions. In sawtoothing discharges with central electron cyclotron heating, outward convection is observed when a quasicontinuous m=1 kink mode is present, resulting in inverted sawteeth on the central electron density, while in the absence thereof, inward convection between successive sawtooth crashes leads to 'normal' sawteeth. The occurrence of a kink mode depends sensitively on plasma triangularity. When sawteeth are stabilized with central co- or counterelectron cyclotron current drive, stationary hollow electron density profiles are observed in the presence of m=1 modes, while peaked or flat profiles are observed in magnetohydrodynamic quiescent discharges. The observation of peaked density profiles in fully electron cyclotron driven plasmas demonstrates that pinch processes other than the Ware pinch must be responsible for these phenomena

  3. High power light gas helicon plasma source for VASIMR

    International Nuclear Information System (INIS)

    Squire, Jared P.; Chang-Diaz, Franklin R.; Glover, Timothy W.; Jacobson, Verlin T.; McCaskill, Greg E.; Winter, D. Scott; Baity, F. Wally; Carter, Mark D.; Goulding, Richard H.

    2006-01-01

    In the Advanced Space Propulsion Laboratory (ASPL) helicon experiment (VX-10) we have measured a plasma flux to input gas rate ratio near 100% for both helium and deuterium at power levels up to 10 kW. Recent results at Oak Ridge National Laboratory (ORNL) show enhanced efficiency operation with a high power density, over 5 kW in a 5 cm diameter tube. Our helicon is presently 9 cm in diameter and operates up to 10 kW of input power. The data here uses a Boswell double-saddle antenna design with a magnetic cusp just upstream of the antenna. Similar to ORNL, for deuterium at near 10 kW, we find an enhanced performance of operation at magnetic fields above the lower hybrid matching condition

  4. Environmental friendly high efficient light source plasma lamp - Final report

    Energy Technology Data Exchange (ETDEWEB)

    Courret, G.; Calame, L. [Haute Ecole d' ingenierie et de gestion du canton de Vaud, Institut de micro et nano techniques, Yverdon-les-Bains (Switzerland); Meyer, A. [Solaronix SA, Aubonne (Switzerland)

    2007-07-01

    This illustrated final report for the Swiss Federal Office of Energy (SFOE) takes a look at work done on the development of a sulphur-based plasma lamp. In 2007, the capability of a new modulator has been explored. The most important results are discussed. With the production of a 1.2 cm{sup 3} bulb, the way towards the production of a 100 W lamp has been opened. The authors comment that modulation by impulses increases the luminous efficiency in comparison to modulation using a continuous sinusoidal wave. The report deals with the history of the project, the development of the new modulator, the use of rotational effects and the optimisation of the amount of active substances - tellurium and selenium - in the bulb. The electromagnetic coupling system used is described and discussed.

  5. Confined discharge plasma sources for Z-pinch experiments

    International Nuclear Information System (INIS)

    Hinshelwood, D.D.; Goodrich, P.J.; Mehlman, G.; Scherrer, V.E.; Stephanakis, S.J.; Young, F.C.

    1989-01-01

    The authors report their investigation Z-pinch implosions on the NRL Gamble II generator using metallic sources of sodium and aluminum, and non-metallic source of sodium (NaF), magnesium (MgF 2 ), and aluminum (Al 2 0 3 ). For 1 MA driving currents, peak Κ-shell radiated powers of about 100 GW and energies of about 1.5 kj have been obtained with both pure aluminum and NaF implosions. The aluminum results are comparable to those in previous Gamble II experiments with aluminum wire arrays. Confined discharge sources have been used to generate tens of GW in the Na Heα pump line and flourescence of the neon has been observed. The effects of nozzle shape and size, chamber diameter, amount of fuse material, and confined discharge current have been investigated in Gamble II implosion experiments. These studies indicate that confined discharge sources are capable of supplying significantly more material than required for implosions at the 1 MA level, so that this technique could be extended to higher current generators

  6. The Sandia laser plasma extreme ultraviolet and soft x-ray (XUV) light source

    International Nuclear Information System (INIS)

    Tooman, T.P.

    1986-01-01

    Laser produced plasmas have been shown to be extremely bright sources of extreme ultraviolet and soft x-ray (XUV) radiation; however, certain practical difficulties have hindered the development of this source as a routinely usable laboratory device. To explore solutions to these difficulties, Sandia has constructed an XUV laser plasma source (LASPS) with the intention of developing an instrument that can be used for experiments requiring intense XUV radiation from 50-300 eV. The driving laser for this source is a KrF excimer with a wavelength of 248 nm, divergence of 200 μrad, pulse width of 23 ns at 20 Hz and typical pulse energy of 500 mJ which allows for good energy coupling to the plasma at moderate (10/sup 12/ W cm/sup 2/) power densities. This source has been pulsed approximately 2 x 10/sup 5/ times, demonstrating good tolerance to plasma debris. The source radiates from the visible to well above 1000 eV, however, to date attention has been concentrated on the 50-300 eV region. In this paper, spectral data and plasma images for both stainless steel and gold targets are presented with the gold target yielding a 200 μm plasma and reradiating 3.9% of the pump energy into 15-73 eV band, a flux of 1.22 x 10/sup 13/ photons/pulse/eV into 2π sr. Further efforts will expand these measurements to rare earth targets and to higher spectral energies. A special high throughput wide angle XUV (50-300 eV) monochromator and associated optics is being concurrently developed to collect the plasma radiation, perform energy dispersion and focus the radiation onto the experimental area

  7. Planned upgrade to the coaxial plasma source facility for high heat flux plasma flows relevant to tokamak disruption simulations

    International Nuclear Information System (INIS)

    Caress, R.W.; Mayo, R.M.; Carter, T.A.

    1995-01-01

    Plasma disruptions in tokamaks remain serious obstacles to the demonstration of economical fusion power. In disruption simulation experiments, some important effects have not been taken into account. Present disruption simulation experimental data do not include effects of the high magnetic fields expected near the PFCs in a tokamak major disruption. In addition, temporal and spatial scales are much too short in present simulation devices to be of direct relevance to tokamak disruptions. To address some of these inadequacies, an experimental program is planned at North Carolina State University employing an upgrade to the Coaxial Plasma Source (CPS-1) magnetized coaxial plasma gun facility. The advantages of the CPS-1 plasma source over present disruption simulation devices include the ability to irradiate large material samples at extremely high areal energy densities, and the ability to perform these material studies in the presence of a high magnetic field. Other tokamak disruption relevant features of CPS-1U include a high ion temperature, high electron temperature, and long pulse length

  8. Model of a source-driven plasma interacting with a wall in an oblique magnetic field

    International Nuclear Information System (INIS)

    Ahedo, E.; Carralero, D.

    2009-01-01

    A fluid model of a magnetized source-driven plasma is discussed for regimes with (Debye length)<<(ion Larmor radius)<<(plasma size and collisional mean-free path). Plasma collection by the wall is determined in terms of angle of incidence, magnetic strength, and plasma collisionality. For nonparallel incidence, a three-scale asymptotic analysis reveals a three-region matched structure consisting of a magnetically aligned bulk region, the Chodura layer, and the Debye sheath. Sonic Chodura and Bohm conditions define the singular region transitions. For near-parallel incidence, a separate analysis demonstrates the presence of a diffusive-collisional bulk region followed by a thin collisionless layer, which differs partially from the Chodura layer. A parametric analysis unveils the presence of four regimes depending on plasma collisionality: (1) a collisionless regime, with the magnetically channeled bulk region governed by plasma production; (2) a resistive semicollisional regime, where collisions retard the plasma transport in the bulk region; (3) a diffusive semicollisional regime, where the ExB drift dominates the ion flux in the bulk region; and (4) a collisional regime, where collisions cancel out magnetic effects. At grazing incidence, plasma collection is found to vary nonmonotonically with plasma collisionality. Nonzero Debye-length effects are discussed briefly.

  9. Characterization of edge turbulence in relation to edge magnetic field configuration in Ohmic L-mode plasmas in the Mega Amp Spherical Tokamak

    Science.gov (United States)

    Hnat, B.; Dudson, B. D.; Dendy, R. O.; Counsell, G. F.; Kirk, A.; MAST Team

    2008-08-01

    Ion saturation current (Isat) measurements of edge plasma turbulence are analysed for six MAST L-mode plasmas that differ primarily in their edge magnetic field configurations. The analysis techniques are designed to capture the strong nonlinearities of the datasets. First, absolute moments of the data are examined to obtain accurate values of scaling exponents. This confirms dual scaling behaviour in all samples, with the temporal scale τ ≈ 40-60 µs separating the two regimes. Strong universality is then identified in the functional form of the probability density function (PDF) for Isat fluctuations, which is well approximated by the Fréchet distribution on temporal scales τ 40 µs, the PDFs appear to converge to the Gumbel distribution, which has been previously identified as a universal feature of many other complex phenomena. The optimal fitting parameters k = 1.15 for Fréchet and a = 1.35 for Gumbel provide a simple quantitative characterization of the full spectrum of fluctuations. It is concluded that, to good approximation, the properties of the edge turbulence are independent of the edge magnetic field configuration.

  10. Experimental behaviour of a argon plasma, which is passed by a high current intensity, with different magnetic field configurations

    International Nuclear Information System (INIS)

    Lozano, J.

    1964-01-01

    In a lineal discharge, the longitudinal and azimuthal magnetic fields produced by the current through the tube and the returning conductors, which have 4 different forms, are determined with a magnetic probe, which has a radial and longitudinal displacement. The plasma is produced discharging a 135μF and 9 KV capacitor bank through Argon at 10 - 1 Torr. (Author) 5 refs

  11. Impact of plasma tube wall thickness on power coupling in ICP sources

    International Nuclear Information System (INIS)

    Nawaz, Anuscheh; Herdrich, Georg

    2009-01-01

    The inductively heated plasma source at the Institute of Space Systems was investigated with respect to the wall thickness of the plasma tube using an air plasma. For this, the wall thickness of the quartz tube was reduced in steps from 2.5 to 1.25 mm. The significance of reducing the wall thickness was analyzed with respect to both the maximum allowable tube cooling power and the coupling efficiency. While the former results from thermal stresses in the tube's wall, the latter results from a minimization of magnetic field losses near the coil turns of the inductively coupled plasma (ICP) source. Analysis of the thermal stress could be validated by experimental data, i.e. the measurement of the tube cooling power when the respective tube structure failed. The coupling efficiency could be assessed qualitatively by simplified models, and the experimental data recorded show that coupling was improved far more than predicted.

  12. Diagnostics of microwave assisted electron cyclotron resonance plasma source for surface modification of nylon 6

    Science.gov (United States)

    More, Supriya E.; Das, Partha Sarathi; Bansode, Avinash; Dhamale, Gayatri; Ghorui, S.; Bhoraskar, S. V.; Sahasrabudhe, S. N.; Mathe, Vikas L.

    2018-01-01

    Looking at the increasing scope of plasma processing of materials surface, here we present the development and diagnostics of a microwave assisted Electron Cyclotron Resonance (ECR) plasma system suitable for surface modification of polymers. Prior to the surface-treatment, a detailed diagnostic mapping of the plasma parameters throughout the reactor chamber was carried out by using single and double Langmuir probe measurements in Ar plasma. Conventional analysis of I-V curves as well as the elucidation form of the Electron Energy Distribution Function (EEDF) has become the source of calibration of plasma parameters in the reaction chamber. The high energy tail in the EEDF of electron temperature is seen to extend beyond 60 eV, at much larger distances from the ECR zone. This proves the suitability of the rector for plasma processing, since the electron energy is much beyond the threshold energy of bond breaking in most of the polymers. Nylon 6 is used as a representative candidate for surface processing in the presence of Ar, H2 + N2, and O2 plasma, treated at different locations inside the plasma chamber. In a typical case, the work of adhesion is seen to almost get doubled when treated with oxygen plasma. Morphology of the plasma treated surface and its hydrophilicity are discussed in view of the variation in electron density and electron temperature at these locations. Nano-protrusions arising from plasma treatment are set to be responsible for the hydrophobicity. Chemical sputtering and physical sputtering are seen to influence the surface morphology on account of sufficient electron energies and increased plasma potential.

  13. Study of electron current extraction from a radio frequency plasma cathode designed as a neutralizer for ion source applications

    Energy Technology Data Exchange (ETDEWEB)

    Jahanbakhsh, Sina, E-mail: sinajahanbakhsh@gmail.com; Satir, Mert; Celik, Murat [Department of Mechanical Engineering, Bogazici University, Istanbul 34342 (Turkey)

    2016-02-15

    Plasma cathodes are insert free devices that are developed to be employed as electron sources in electric propulsion and ion source applications as practical alternatives to more commonly used hollow cathodes. Inductively coupled plasma cathodes, or Radio Frequency (RF) plasma cathodes, are introduced in recent years. Because of its compact geometry, and simple and efficient plasma generation, RF plasma source is considered to be suitable for plasma cathode applications. In this study, numerous RF plasma cathodes have been designed and manufactured. Experimental measurements have been conducted to study the effects of geometric and operational parameters. Experimental results of this study show that the plasma generation and electron extraction characteristics of the RF plasma cathode device strongly depend on the geometric parameters such as chamber diameter, chamber length, orifice diameter, orifice length, as well as the operational parameters such as RF power and gas mass flow rate.

  14. Behavior of moving plasma in solenoidal magnetic field in a laser ion source

    International Nuclear Information System (INIS)

    Ikeda, S.; Takahashi, K.; Okamura, M.; Horioka, K.

    2016-01-01

    In a laser ion source, a solenoidal magnetic field is useful to guide the plasma and to control the extracted beam current. However, the behavior of the plasma drifting in the magnetic field has not been well understood. Therefore, to investigate the behavior, we measured the plasma ion current and the total charge within a single pulse in the solenoid by changing the distance from the entrance of the solenoid to a detector. We observed that the decrease of the total charge along the distance became smaller as the magnetic field became larger and then the charge became almost constant with a certain magnetic flux density. The results indicate that the transverse spreading speed of the plasma decreased with increasing the field and the plasma was confined transversely with the magnetic flux density. We found that the reason of the confinement was not magnetization of ions but an influence induced by electrons

  15. Behavior of moving plasma in solenoidal magnetic field in a laser ion source

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, S., E-mail: ikeda.s.ae@m.titech.ac.jp [Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, Yokohama, Kanagawa 226-8502 (Japan); Nishina Center for Accelerator-Based Science, RIKEN, Wako, Saitama 351-0108 (Japan); Takahashi, K. [Department of Electrical Engineering, Nagaoka University of Technology, Nagaoka, Niigata 940-2137 (Japan); Okamura, M. [Collider-Accelerator Department, Brookhaven National Laboratory, Upton, New York 11973-5000 (United States); Horioka, K. [Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, Yokohama, Kanagawa 226-8502 (Japan)

    2016-02-15

    In a laser ion source, a solenoidal magnetic field is useful to guide the plasma and to control the extracted beam current. However, the behavior of the plasma drifting in the magnetic field has not been well understood. Therefore, to investigate the behavior, we measured the plasma ion current and the total charge within a single pulse in the solenoid by changing the distance from the entrance of the solenoid to a detector. We observed that the decrease of the total charge along the distance became smaller as the magnetic field became larger and then the charge became almost constant with a certain magnetic flux density. The results indicate that the transverse spreading speed of the plasma decreased with increasing the field and the plasma was confined transversely with the magnetic flux density. We found that the reason of the confinement was not magnetization of ions but an influence induced by electrons.

  16. Behavior of moving plasma in solenoidal magnetic field in a laser ion source

    Science.gov (United States)

    Ikeda, S.; Takahashi, K.; Okamura, M.; Horioka, K.

    2016-02-01

    In a laser ion source, a solenoidal magnetic field is useful to guide the plasma and to control the extracted beam current. However, the behavior of the plasma drifting in the magnetic field has not been well understood. Therefore, to investigate the behavior, we measured the plasma ion current and the total charge within a single pulse in the solenoid by changing the distance from the entrance of the solenoid to a detector. We observed that the decrease of the total charge along the distance became smaller as the magnetic field became larger and then the charge became almost constant with a certain magnetic flux density. The results indicate that the transverse spreading speed of the plasma decreased with increasing the field and the plasma was confined transversely with the magnetic flux density. We found that the reason of the confinement was not magnetization of ions but an influence induced by electrons.

  17. Confinement of laser plasma by solenoidal field for laser ion source

    International Nuclear Information System (INIS)

    Okamura, M.; Kanesue, T.; Kondo, K.; Dabrowski, R.

    2010-01-01

    A laser ion source can provide high current, highly charged ions with a simple structure. However, it was not easy to control the ion pulse width. To provide a longer ion beam pulse, the plasma drift length, which is the distance between laser target and extraction point, has to be extended and as a result the plasma is diluted severely. Previously, we applied a solenoid field to prevent reduction of ion density at the extraction point. Although a current enhancement by a solenoid field was observed, plasma behavior after a solenoid magnet was unclear because plasma behavior can be different from usual ion beam dynamics. We measured a transverse ion distribution along the beam axis to understand plasma motion in the presence of a solenoid field.

  18. A new high-temperature plasma ion source for the TRISTAN ISOL facility

    International Nuclear Information System (INIS)

    Piotrowski, A.; Gill, R.L.; McDonald, D.C.

    1987-01-01

    A vigorous program of ion-source development at TRISTAN has led to several types of ion sources that are especially suited to extended operation at a reactor-based ISOL facility. The latest of these is a high-temperature plasma ion source in which a 5-g /sup 235/U target is located in the cathode and can be heated to 2500 0 C. The ion source has a lifetime of > 1000 h and produces a wide array of elements, including palladium. Off-line investigations indicate that the source functions primarily in an electron impact mode of ionization and exhibits typical ionization efficiencies of > 30% for xenon

  19. A new high-temperature plasma ion source for the TRISTAN ISOL facility

    International Nuclear Information System (INIS)

    Piotrowski, A.; Gill, R.L.; McDonald, D.C.

    1987-01-01

    A vigorous program of ion-source development at TRISTAN has led to several types of ion sources that are especially suited to extended operation at a reactor-based ISOL facility. The latest of these is a high-temperature plasma ion source in which a 5-g 235 U target is located in the cathode and can be heated to 2500 0 C. The ion source has a lifetime of >1000 h and produces a wide array of elements, including palladium. Off-line investigations indicate that the source functions primarily in an electron impact mode of ionization and exhibits typical ionization efficiencies of >30% for xenon. (orig.)

  20. New high temperature plasma ion source for the TRISTAN ISOL facility

    International Nuclear Information System (INIS)

    Piotrowski, A.; Gill, R.L.; McDonald, D.C.

    1986-08-01

    A vigorous program of ion source development at TRISTAN has led to several types of ion sources that are especially suited to extended operation at a reactor-based ISOL facility. The latest of these is a high temperature plasma ion source in which a 5 gm 235 U target is located in the cathode and can be heated to 2500 0 C. The ion source has a lifetime of >1000 hours and produces a wide array of elements, including Pd. Off-line investigations indicate that the source functions primarily in an electron impact mode of ionization and exhibits typical ionzation efficiencies of >30% for Xe

  1. Inductively coupled plasma and ion sources: History and state-of-the-art

    International Nuclear Information System (INIS)

    Hopwood, J.

    1994-01-01

    Over 100 years ago Hittorf first generated an electrodeless ''ring'' discharge by electromagnetic induction and began a 40 year controversy as to the true physical origin of such a discharge. Even Tesla advocated that these plasmas were merely the result of large electrostatic potential differences rather than electric fields induced by high frequency currents. Through clever experiments using crude spark gaps and leyden jars, the inductive nature of the discharge was confirmed in the late 1920's by MacKinnon, thus supporting the theories and experiments of Sir J.J. Thomson, perhaps the most staunch advocate of the induction mechanism. Today the authors routinely exploit the intense plasmas which are generated by induction. In this talk, the characteristics of inductively coupled plasma (ICP) and ion sources will be reviewed and future applications of intense plasma sources will be discussed. The inductively coupled plasma is Joule heated at moderate gas pressures, but the electromagnetic field penetration of these dense plasmas is limited by the plasma skin depth, typically a few millimeters to a few centimeters. The induction plasma is thus edge heated, a fact that constrains uniformity over large areas if helical induction coils are used. Flat, spiral coils may be used to improve uniformity by driving the plasma using a planar geometry. Issues of dimensional and frequency scaling will be discussed as they apply to large diameter sources. Ion beams extracted from ICPs are used for many applications including space propulsion, high power neutral beams, and materials processing. Broad ion beam (∼10 cm) current densities in excess of 100 mA-cm 2 at 100 keV are obtained in pulsed mode operation. Recently, however, more consumer-oriented applications of less intense ICPs are emerging

  2. Sources plasma RF magnétisées : applications à la propulsion spatiale

    OpenAIRE

    Gerst , Jan Dennis

    2013-01-01

    The PEGASES thruster (Plasma Propulsion with Electronegative Gases) is a novel type of electric thruster for space propulsion. It uses negative and positive ions produced by an inductively coupled radio frequency discharge to create the thrust by electrostatically accelerating the ions through a set of grids. A magnetic filter is used to increase the amount of negative ions in the cavity of the thruster. The PEGASES thruster is not only a source to create a strongly negative ion plasma or eve...

  3. Glovebox enclosed dc plasma source for the determination of metals in plutonium

    International Nuclear Information System (INIS)

    Morris, W.F.

    1986-01-01

    The direct current plasma source of a Beckman Spectraspan IIIB emission spectrometer was enclosed in a glovebox at Lawrence Livermore National Laboratory in December 1982. Since that time, the system has been used for the routine determination of alloy and impurity metals in plutonium. This paper presents the systematic steps involved in developing the glovebox and gives information regarding performance of the plasma in the glovebox and the effectiveness of containment of plutonium. 8 refs., 9 figs., 3 tabs

  4. Sheath physics and materials science results from recent plasma source ion implantation experiments

    International Nuclear Information System (INIS)

    Conrad, J.R.; Radtke, J.L.; Dodd, R.A.; Worzala, F.J.

    1987-01-01

    Plasma Source Ion Implantation (PSII) is a surface modification technique which has been optimized for ion-beam processing of materials. PSII departs radically from conventional implantation by circumventing the line of sight restriction inherent in conventional ion implantation. The authors used PSII to implant cutting tools and dies and have demonstrated substantial improvements in lifetime. Recent results on plasma physics scaling laws, microstructural, mechanical, and tribological properties of PSII-implanted materials are presented

  5. Neutral Beam Source and Target Plasma for Development of a Local Electric Field Fluctuation Diagnostic

    Science.gov (United States)

    Bakken, M. R.; Burke, M. G.; Fonck, R. J.; Lewicki, B. T.; Rhodes, A. T.; Winz, G. R.

    2016-10-01

    A new diagnostic measuring local E-> (r , t) fluctuations is being developed for plasma turbulence studies in tokamaks. This is accomplished by measuring fluctuations in the separation of the π components in the Hα motional Stark spectrum. Fluctuations in this separation are expected to be Ẽ / ẼEMSE 10-3EMSE 10-3 . In addition to a high throughput, high speed spectrometer, the project requires a low divergence (Ω 0 .5°) , 80 keV, 2.5 A H0 beam and a target plasma test stand. The beam employs a washer-stack arc ion source to achieve a high species fraction at full energy. Laboratory tests of the ion source demonstrate repeatable plasmas with Te 10 eV and ne 1.6 ×1017 m-3, sufficient for the beam ion optics requirements. Te and ne scalings of the ion source plasma are presented with respect to operational parameters. A novel three-phase resonant converter power supply will provide 6 mA/cm2 of 80 keV H0 at the focal plane for pulse lengths up to 15 ms, with low ripple δV / 80 keV 0.05 % at 280 kHz. Diagnostic development and validation tests will be performed on a magnetized plasma test stand with 0.5 T field. The test chamber will utilize a washer-stack arc source to produce a target plasma comparable to edge tokamak plasmas. A bias-plate with programmable power supply will be used to impose Ẽ within the target plasma. Work supported by US DOE Grant DE-FG02-89ER53296.

  6. Silicon micromachining using a high-density plasma source

    International Nuclear Information System (INIS)

    McAuley, S.A.; Ashraf, H.; Atabo, L.; Chambers, A.; Hall, S.; Hopkins, J.; Nicholls, G.

    2001-01-01

    Dry etching of Si is critical in satisfying the demands of the micromachining industry. The micro-electro-mechanical systems (MEMS) community requires etches capable of high aspect ratios, vertical profiles, good feature size control and etch uniformity along with high throughput to satisfy production requirements. Surface technology systems' (STS's) high-density inductively coupled plasma (ICP) etch tool enables a wide range of applications to be realized whilst optimizing the above parameters. Components manufactured from Si using an STS ICP include accelerometers and gyroscopes for military, automotive and domestic applications. STS's advanced silicon etch (ASE TM ) has also allowed the first generation of MEMS-based optical switches and attenuators to reach the marketplace. In addition, a specialized application for fabricating the next generation photolithography exposure masks has been optimized for 200 mm diameter wafers, to depths of ∼750 μm. Where the profile is not critical, etch rates of greater than 8 μm min -1 have been realized to replace previous methods such as wet etching. This is also the case for printer applications. Specialized applications that require etching down to pyrex or oxide often result in the loss of feature size control at the interface; this is an industry wide problem. STS have developed a technique to address this. The rapid progression of the industry has led to development of the STS ICP etch tool, as well as the process. (author)

  7. Optical emission spectroscopy of carbon laser plasma ion source

    Science.gov (United States)

    Balki, Oguzhan; Rahman, Md. Mahmudur; Elsayed-Ali, Hani E.

    2018-04-01

    Carbon laser plasma generated by an Nd:YAG laser (wavelength 1064 nm, pulse width 7 ns, fluence 4-52 J cm-2) is studied by optical emission spectroscopy and ion time-of-flight. Up to C4+ ions are detected with the ion flux strongly dependent on the laser fluence. The increase in ion charge with the laser fluence is accompanied by observation of multicharged ion lines in the optical spectra. The time-integrated electron temperature Te is calculated from the Boltzmann plot using the C II lines at 392.0, 426.7, and 588.9 nm. Te is found to increase from ∼0.83 eV for a laser fluence of 22 J cm-2 to ∼0.90 eV for 40 J cm-2. The electron density ne is obtained from the Stark broadened profiles of the C II line at 392 nm and is found to increase from ∼ 2 . 1 × 1017cm-3 for 4 J cm-2 to ∼ 3 . 5 × 1017cm-3 for 40 J cm-2. Applying an external electric field parallel to the expanding plume shows no effect on the line emission intensities. Deconvolution of ion time-of-flight signal with a shifted Maxwell-Boltzmann distribution for each charge state results in an ion temperature Ti ∼4.7 and ∼6.0 eV for 20 and 36 J cm-2, respectively.

  8. Hard X-ray sources from miniature plasma focus devices

    International Nuclear Information System (INIS)

    Raspa, V.; Silva, P.; Moreno, J.; Zambra, M.; Soto, L.

    2004-01-01

    As first stage of a program to design a repetitive pulsed radiation generator for industrial applications, two miniature plasma foci have been designed and constructed at the Chilean commission of nuclear energy. The devices operate at an energy level of the order of tens of joules (PF-50 J, 160 nF capacitor bank, 20-35 kV, 32-100 J, ∼ 150 ns time to peak current) and hundred of joules (PF-400 J, 880 nF, 20-35 kV, 176-539 J, ∼ 300 ns time to peak current). Hard X-rays are being studied in these devices operating with hydrogen. Images of metallic plates with different thickness were obtained on commercial radiographic film, Agfa Curix ST-G2, in order to characterize the energy of the hard X-ray outside of the discharge chamber of PF-400 J. An effective energy of the order of 90 keV was measured under those conditions. X ray images of different metallic objects also have been obtained. (authors)

  9. Hard X-ray sources from miniature plasma focus devices

    Energy Technology Data Exchange (ETDEWEB)

    Raspa, V. [Buenos Aires Univ., PLADEMA, CONICET and INFIP (Argentina); Silva, P.; Moreno, J.; Zambra, M.; Soto, L. [Comision Chilena de Energia Nuclear, Santiago (Chile)

    2004-07-01

    As first stage of a program to design a repetitive pulsed radiation generator for industrial applications, two miniature plasma foci have been designed and constructed at the Chilean commission of nuclear energy. The devices operate at an energy level of the order of tens of joules (PF-50 J, 160 nF capacitor bank, 20-35 kV, 32-100 J, {approx} 150 ns time to peak current) and hundred of joules (PF-400 J, 880 nF, 20-35 kV, 176-539 J, {approx} 300 ns time to peak current). Hard X-rays are being studied in these devices operating with hydrogen. Images of metallic plates with different thickness were obtained on commercial radiographic film, Agfa Curix ST-G2, in order to characterize the energy of the hard X-ray outside of the discharge chamber of PF-400 J. An effective energy of the order of 90 keV was measured under those conditions. X ray images of different metallic objects also have been obtained. (authors)

  10. Fullerene-rare gas mixed plasmas in an electron cyclotron resonance ion source

    Energy Technology Data Exchange (ETDEWEB)

    Asaji, T., E-mail: asaji@oshima-k.ac.jp; Ohba, T. [Oshima National College of Maritime Technology, 1091-1 Komatsu, Suo-oshima, Oshima, Yamaguchi 742-2193 (Japan); Uchida, T.; Yoshida, Y. [Bio-Nano Electronics Research Centre, Toyo University, 2100 Kujirai, Kawagoe, Saitama 350-8585 (Japan); Minezaki, H.; Ishihara, S. [Graduate School of Engineering, Toyo University, 2100 Kujirai, Kawagoe, Saitama 350-8585 (Japan); Racz, R.; Biri, S. [Institute of Nuclear Research (ATOMKI), H-4026 Debrecen, Bem Tér 18/c (Hungary); Muramatsu, M.; Kitagawa, A. [National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan); Kato, Y. [Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871 (Japan)

    2014-02-15

    A synthesis technology of endohedral fullerenes such as Fe@C{sub 60} has developed with an electron cyclotron resonance (ECR) ion source. The production of N@C{sub 60} was reported. However, the yield was quite low, since most fullerene molecules were broken in the ECR plasma. We have adopted gas-mixing techniques in order to cool the plasma and then reduce fullerene dissociation. Mass spectra of ion beams extracted from fullerene-He, Ar or Xe mixed plasmas were observed with a Faraday cup. From the results, the He gas mixing technique is effective against fullerene destruction.

  11. Deposition of dielectric films on silicon using a fore-vacuum plasma electron source

    Energy Technology Data Exchange (ETDEWEB)

    Zolotukhin, D. B.; Tyunkov, A. V.; Yushkov, Yu. G., E-mail: yuyushkov@gmail.com [Tomsk State University of Control Systems and Radioelectronics, 40 Lenin Ave., Tomsk 634050 (Russian Federation); Oks, E. M. [Tomsk State University of Control Systems and Radioelectronics, 40 Lenin Ave., Tomsk 634050 (Russian Federation); Institute of High Current Electronics SB RAS, 2/3, Akademichesky Ave., Tomsk 634055 (Russian Federation)

    2016-06-15

    We describe an experiment on the use of a fore-vacuum-pressure, plasma-cathode, electron beam source with current up to 100 mA and beam energy up to 15 keV for deposition of Mg and Al oxide films on Si substrates in an oxygen atmosphere at a pressure of 10 Pa. The metals (Al and Mg) were evaporated and ionized using the electron beam with the formation of a gas-metal beam-plasma. The plasma was deposited on the surface of Si substrates. The elemental composition of the deposited films was analyzed.

  12. Development of long lifetime-high current plasma cathode ion source

    International Nuclear Information System (INIS)

    Yabe, Eiji; Takayama, Kazuo; Fukui, Ryota.

    1987-01-01

    A long lifetime ion source with plasma cathode has been developed for use in ion implantation. In this ion source, a plasma of a nonreactive working gas serves as a cathode in place of a thermionic tungsten filament used in the Freeman ion source. In an applied magnetic field, the plasma cathode is convergent, i.e. filament-like; in zero magnetic field, it turns divergent and spray-like. In the latter case, the plasma exhibits a remarkable ability when the working gas has an ionization potential larger than the feed gas. By any combination of a working gas of either argon or neon and a feed gas of AsF 5 or PF 5 , the lifetime of this ion source was found to be more than 90 hours with an extraction voltage of 40 kV and the corresponding ion current density 20 mA/cm 2 . Mass spectrometry results show that this ion source has an ability of generating a considerable amount of As + and P + ions from AsF 5 and PF 5 , and hence will be useful for realizing a fully cryopumped ion implanter system. This ion source is eminently suitable for use in oxygen ion production. (author)

  13. Tungsten transport and sources control in JET ITER-like wall H-mode plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Fedorczak, N., E-mail: nicolas.fedorczak@cea.fr [CEA, IRFM, F-13108 Saint-Paul-Lez-Durance (France); Monier-Garbet, P. [CEA, IRFM, F-13108 Saint-Paul-Lez-Durance (France); Pütterich, T. [MPI für Plasmaphysik, EURATOM Association, Boltzmannstrasse 2, 85748 Garching (Germany); Brezinsek, S. [Institute of Energy and Climate Research, Forschungszentrum Jlich, Assoc EURATOM-FZJ, Jlich (Germany); Devynck, P.; Dumont, R.; Goniche, M.; Joffrin, E. [CEA, IRFM, F-13108 Saint-Paul-Lez-Durance (France); Lerche, E. [Association EURATOM-Belgian State, LPP-ERM-KMS, TEC partner, Brussels (Belgium); Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Lipschultz, B. [York Plasma Institute, University of York, Heslington, York YO10 5DD (United Kingdom); Luna, E. de la [Laboratorio Nacional de Fusin, Asociacin EURATOM/CIEMAT, 28040 Madrid (Spain); Maddison, G. [Culham Centre for Fusion Energy, EURATOM-CCFE Association, Abingdon (United Kingdom); Maggi, C. [MPI für Plasmaphysik, EURATOM Association, Boltzmannstrasse 2, 85748 Garching (Germany); Matthews, G. [Culham Centre for Fusion Energy, EURATOM-CCFE Association, Abingdon (United Kingdom); Nunes, I. [Istituto de plasmas e fusao nuclear, Lisboa (Portugal); Rimini, F. [Culham Centre for Fusion Energy, EURATOM-CCFE Association, Abingdon (United Kingdom); Solano, E.R. [Laboratorio Nacional de Fusin, Asociacin EURATOM/CIEMAT, 28040 Madrid (Spain); Tamain, P. [CEA, IRFM, F-13108 Saint-Paul-Lez-Durance (France); Tsalas, M. [Association EURATOM-Hellenic Republic, NCSR Demokritos 153 10, Attica (Greece); Vries, P. de [ITER Organization, Route de Vinon sur Verdon, 13115 Saint Paul Lez Durance (France)

    2015-08-15

    A set of discharges performed with the JET ITER-like wall is investigated with respect to control capabilities on tungsten sources and transport. In attached divertor regimes, increasing fueling by gas puff results in higher divertor recycling ion flux, lower divertor tungsten source, higher ELM frequency and lower core plasma radiation, dominated by tungsten ions. Both pedestal flushing by ELMs and divertor screening (including redeposition) are possibly responsible. For specific scenarios, kicks in plasma vertical position can be employed to increase the ELM frequency, which results in slightly lower core radiation. The application of ion cyclotron radio frequency heating at the very center of the plasma is efficient to increase the core electron temperature gradient and flatten electron density profile, resulting in a significantly lower central tungsten peaking. Beryllium evaporation in the main chamber did not reduce the local divertor tungsten source whereas core radiation was reduced by approximately 50%.

  14. Characteristics of cold atmospheric plasma source based on low-current pulsed discharge with coaxial electrodes

    Science.gov (United States)

    Bureyev, O. A.; Surkov, Yu S.; Spirina, A. V.

    2017-05-01

    This work investigates the characteristics of the gas discharge system used to create an atmospheric pressure plasma flow. The plasma jet design with a cylindrical graphite cathode and an anode rod located on the axis of the system allows to realize regularly reproducible spark breakdowns mode with a frequency ∼ 5 kHz and a duration ∼ 40 μs. The device generates a cold atmospheric plasma flame with 1 cm in diameter in the flow of various plasma forming gases including nitrogen and air at about 100 mA average discharge current. In the described construction the cathode spots of individual spark channels randomly move along the inner surface of the graphite electrode creating the secondary plasma stream time-average distributed throughout the whole exit aperture area after the decay of numerous filamentary discharge channels. The results of the spectral diagnostics of plasma in the discharge gap and in the stream coming out of the source are presented. Despite the low temperature of atoms and molecules in plasma stream the cathode spots operation with temperature of ∼ 4000 °C at a graphite electrode inside a discharge system enables to saturate the plasma by CN-radicals and atomic carbon in the case of using nitrogen as the working gas.

  15. Non-thermal atmospheric pressure HF plasma source: generation of nitric oxide and ozone for bio-medical applications

    Science.gov (United States)

    Kühn, S.; Bibinov, N.; Gesche, R.; Awakowicz, P.

    2010-01-01

    A new miniature high-frequency (HF) plasma source intended for bio-medical applications is studied using nitrogen/oxygen mixture at atmospheric pressure. This plasma source can be used as an element of a plasma source array for applications in dermatology and surgery. Nitric oxide and ozone which are produced in this plasma source are well-known agents for proliferation of the cells, inhalation therapy for newborn infants, disinfection of wounds and blood ozonation. Using optical emission spectroscopy, microphotography and numerical simulation, the gas temperature in the active plasma region and plasma parameters (electron density and electron distribution function) are determined for varied nitrogen/oxygen flows. The influence of the gas flows on the plasma conditions is studied. Ozone and nitric oxide concentrations in the effluent of the plasma source are measured using absorption spectroscopy and electro-chemical NO-detector at variable gas flows. Correlations between plasma parameters and concentrations of the particles in the effluent of the plasma source are discussed. By varying the gas flows, the HF plasma source can be optimized for nitric oxide or ozone production. Maximum concentrations of 2750 ppm and 400 ppm of NO and O3, correspondingly, are generated.

  16. Efficient 'water window' soft x-ray high-Z plasma source

    International Nuclear Information System (INIS)

    Higashiguchi, T; Otsuka, T; Jiang, W; Endo, A; Li, B; Dunne, P; O'Sullivan, G

    2013-01-01

    Unresolved transition array (UTA) is scalable to shorter wavelengths, and we demonstrate a table-top broadband emission 'water window' soft x-ray source based on laser-produced plasmas. Resonance emission from multiply charged ions merges to produce intense UTAs in the 2 to 4 nm region, extending below the carbon K edge (4.37 nm). An outline of a microscope design for single-shot live cell imaging is proposed based on a bismuth (Bi) plasma UTA source, coupled to multilayer mirror optics

  17. Characterization of noise sources in a rod-airfoil configuration by means of Time-Resolved Tomographic PIV

    NARCIS (Netherlands)

    Lorenzoni, V.; Violato, D.; Scarano, F.

    2010-01-01

    Time-resolved Tomographic PIV was used to characterize the flow around the leading edge of a NACA 0012 airfoil in rod-airfoil configuration at ReD = 3500. The volumetric approach at relatively high temporal resolution allows the measurement of the evolution of the 3D vortical structures constituting

  18. Compact radio sources as a plasma turbulent reactor

    International Nuclear Information System (INIS)

    Atoyan, A.M.; Nagapetyan, A.

    1987-01-01

    The electromagnetic raiation spectra of a homogeneous cosmic radio source (CRS) wherein the relativistic electron acceleration on the langmuir waves leads to the formation of Maxwell-like spectra with characteristic value of the Lorentz-factor γ 0 ∼ 10 3 are considered. It has been shown that due to synchrotron radiation of relativistic electrons, usually observed from CRSs flat radiosepctra, gradually steepening at submillimeter wavelengths are naturally formed in the optically thin range of frequencies. The electromagnetic radiation at the scattering of the electron on the turbulence produces significant nonthermal infrared radiation. Inverse compton scattering of the relativistic electrons on the radio-infrared photons leads the production of X-rays. The characteristic of the electromagnetic radiation spectra obtained in the model are compared with the observational ones

  19. Enhancement of Ar sup 8 sup + ion beam intensity from RIKEN 18 GHz electron cyclotron resonance ion source by optimizing the magnetic field configuration

    CERN Document Server

    Higurashi, Y; Kidera, M; Kase, M; Yano, Y; Aihara, T

    2003-01-01

    We successfully produced a 1.55 emA Ar sup 8 sup + ion beam using the RIKEN 18 GHz electron cyclotron resonance ion source at a microwave power of 700 W. To produce such an intense beam, we optimized the minimum magnetic field of mirror magnetic field and plasma electrode position. (author)

  20. Compact quasi-monoenergetic photon sources from laser-plasma accelerators for nuclear detection and characterization

    Energy Technology Data Exchange (ETDEWEB)

    Geddes, Cameron G.R., E-mail: cgrgeddes@lbl.gov; Rykovanov, Sergey; Matlis, Nicholas H.; Steinke, Sven; Vay, Jean-Luc; Esarey, Eric H.; Ludewigt, Bernhard; Nakamura, Kei; Quiter, Brian J.; Schroeder, Carl B.; Toth, Csaba; Leemans, Wim P.

    2015-05-01

    Near-monoenergetic photon sources at MeV energies offer improved sensitivity at greatly reduced dose for active interrogation, and new capabilities in treaty verification, nondestructive assay of spent nuclear fuel and emergency response. Thomson (also referred to as Compton) scattering sources are an established method to produce appropriate photon beams. Applications are however restricted by the size of the required high-energy electron linac, scattering (photon production) system, and shielding for disposal of the high energy electron beam. Laser-plasma accelerators (LPAs) produce GeV electron beams in centimeters, using the plasma wave driven by the radiation pressure of an intense laser. Recent LPA experiments are presented which have greatly improved beam quality and efficiency, rendering them appropriate for compact high-quality photon sources based on Thomson scattering. Designs for MeV photon sources utilizing the unique properties of LPAs are presented. It is shown that control of the scattering laser, including plasma guiding, can increase photon production efficiency. This reduces scattering laser size and/or electron beam current requirements to scale compatible with the LPA. Lastly, the plasma structure can decelerate the electron beam after photon production, reducing the size of shielding required for beam disposal. Together, these techniques provide a path to a compact photon source system.

  1. Design and development of a highly sensitive, field portable plasma source instrument for on-line liquid stream monitoring and real-time sample analysis

    International Nuclear Information System (INIS)

    Duan, Yixiang; Su, Yongxuan; Jin, Zhe; Abeln, Stephen P.

    2000-01-01

    The development of a highly sensitive, field portable, low-powered instrument for on-site, real-time liquid waste stream monitoring is described in this article. A series of factors such as system sensitivity and portability, plasma source, sample introduction, desolvation system, power supply, and the instrument configuration, were carefully considered in the design of the portable instrument. A newly designed, miniature, modified microwave plasma source was selected as the emission source for spectroscopy measurement, and an integrated small spectrometer with a charge-coupled device detector was installed for signal processing and detection. An innovative beam collection system with optical fibers was designed and used for emission signal collection. Microwave plasma can be sustained with various gases at relatively low power, and it possesses high detection capabilities for both metal and nonmetal pollutants, making it desirable to use for on-site, real-time, liquid waste stream monitoring. An effective in situ sampling system was coupled with a high efficiency desolvation device for direct-sampling liquid samples into the plasma. A portable computer control system is used for data processing. The new, integrated instrument can be easily used for on-site, real-time monitoring in the field. The system possesses a series of advantages, including high sensitivity for metal and nonmetal elements; in situ sampling; compact structure; low cost; and ease of operation and handling. These advantages will significantly overcome the limitations of previous monitoring techniques and make great contributions to environmental restoration and monitoring. (c)

  2. An XML-based configuration system for MAST PCS

    International Nuclear Information System (INIS)

    Storrs, J.; McArdle, G.

    2008-01-01

    MAST PCS, a port of General Atomics' generic Plasma Control System, is a large software system comprising many source files in C and IDL. Application parameters can affect multiple source files in complex ways, making code development and maintenance difficult. The MAST PCS configuration system aims to make the task of the application developer easier, through the use of XML-based configuration files and a configuration tool which processes them. It is presented here as an example of a useful technique with wide application

  3. Atomic processes and equation of state of high Z plasmas for EUV sources and their effects on the spatial and temporal evolution of the plasmas

    Science.gov (United States)

    Sasaki, Akira; Sunahara, Atushi; Furukawa, Hiroyuki; Nishihara, Katsunobu; Nishikawa, Takeshi; Koike, Fumihiro

    2016-03-01

    Laser-produced plasma (LPP) extreme ultraviolet (EUV) light sources have been intensively investigated due to potential application to next-generation semiconductor technology. Current studies focus on the atomic processes and hydrodynamics of plasmas to develop shorter wavelength sources at λ = 6.x nm as well as to improve the conversion efficiency (CE) of λ = 13.5 nm sources. This paper examines the atomic processes of mid-z elements, which are potential candidates for λ = 6.x nm source using n=3-3 transitions. Furthermore, a method to calculate the hydrodynamics of the plasmas in terms of the initial interaction between a relatively weak prepulse laser is presented.

  4. Characterization of a Distributed Plasma Ionization Source (DPIS) for Ion Mobility Spectrometry and Mass Spectrometry

    International Nuclear Information System (INIS)

    Waltman, Melanie J.; Dwivedi, Prabha; Hill, Herbert; Blanchard, William C.; Ewing, Robert G.

    2008-01-01

    A recently developed atmospheric pressure ionization source, a distributed plasma ionization source (DPIS), was characterized and compared to commonly used atmospheric pressure ionization sources with both mass spectrometry and ion mobility spectrometry. The source consisted of two electrodes of different sizes separated by a thin dielectric. Application of a high RF voltage across the electrodes generated plasma in air yielding both positive and negative ions depending on the polarity of the applied potential. These reactant ions subsequently ionized the analyte vapors. The reactant ions generated were similar to those created in a conventional point-to-plane corona discharge ion source. The positive reactant ions generated by the source were mass identified as being solvated protons of general formula (H2O)nH+ with (H2O)2H+ as the most abundant reactant ion. The negative reactant ions produced were mass identified primarily as CO3-, NO3-, NO2-, O3- and O2- of various relative intensities. The predominant ion and relative ion ratios varied depending upon source construction and supporting gas flow rates. A few compounds including drugs, explosives and environmental pollutants were selected to evaluate the new ionization source. The source was operated continuously for several months and although deterioration was observed visually, the source continued to produce ions at a rate similar that of the initial conditions. The results indicated that the DPIS may have a longer operating life than a conventional corona discharge.

  5. Enhancement of H{sup -}/D{sup -} volume production in a double plasma type negative ion source

    Energy Technology Data Exchange (ETDEWEB)

    Fukumasa, Osamu; Nishimura, Hideki; Sakiyama, Satoshi [Yamaguchi Univ., Ube (Japan). Faculty of Engineering

    1997-02-01

    H{sup -}/D{sup -} production in a pure volume source has been studied. In our double plasma type negative ion source, both energy and density of fast electrons are well controlled. With the use of this source, the enhancement of H{sup -}/D{sup -} production has been observed. Namely, under the same discharge power, the extracted H{sup -}/D{sup -} current in the double plasma operation is higher than that in the single plasma operation. At the same time, measurements of plasma parameters have been made in the source and the extractor regions for these two cases. (author)

  6. Application of atmospheric plasma sources in growth and differentiation of plant and mammalian stem cells

    Science.gov (United States)

    Puac, Nevena

    2014-10-01

    The expansion of the plasma medicine and its demand for in-vivo treatments resulted in fast development of various plasma devices that operate at atmospheric pressure. These sources have to fulfill all demands for application on biological samples. One of the sources that meet all the requirements needed for treatment of biological material is plasma needle. Previously, we have used this device for sterilization of planctonic samples of bacteria, MRSA biofilm, for improved differentiation of human periodontal stem cells into osteogenic line and for treatment of plant meristematic cells. It is well known that plasma generates reactive oxygen species (ROS) and reactive nitrogen species (RNS) that strongly affect metabolism of living cells. One of the open issues is to correlate external plasma products (electrons, ions, RNS, ROS, photons, strong fields etc.) with the immediate internal response which triggers or induces effects in the living cell. For that purpose we have studied the kinetics of enzymes which are typical indicators of the identity of reactive species from the plasma created environment that can trigger signal transduction in the cell and ensue cell activity. In collaboration with Suzana Zivkovicm, Institute for Biological Research ``Sinisa Stankovic,'' University of Belgrade; Nenad Selakovic, Institute of Physics, University of Belgrade; Milica Milutinovic, Jelena Boljevic, Institute for Biological Research ``Sinisa Stankovic,'' University of Belgrade; and Gordana Malovic, Zoran Lj. Petrovic, Institute of Physics, University of Belgrade. Grants III41011, ON171037 and ON173024, MESTD, Serbia.

  7. Production and transport chemistry of atomic fluorine in remote plasma source and cylindrical reaction chamber

    International Nuclear Information System (INIS)

    Gangoli, S P; Johnson, A D; Fridman, A A; Pearce, R V; Gutsol, A F; Dolgopolsky, A

    2007-01-01

    Increasingly, NF 3 -based plasmas are being used in semiconductor manufacturing to clean chemical vapour deposition (CVD) chambers. With advantages such as faster clean times, substantially lower emissions of gases having high global warming potentials, and reduced chamber damage, NF 3 plasmas are now favoured over fluorocarbon-based processes. Typically, a remote plasma source (RPS) is used to dissociate the NF 3 gas and produce atomic fluorine that etches the CVD residues from the chamber surfaces. However, it is important to efficiently transport F atoms from the plasma source into the process chamber. The current work is aimed at understanding and improving the key processes involved in the production and transport of atomic fluorine atoms. A zero-dimensional model of NF 3 dissociation and F production chemistry in the RPS is developed based on various known and derived plasma parameters. Additionally, a model describing the transport of atomic fluorine is proposed that includes both physical (diffusion, adsorption and desorption) and chemical processes (surface and three-body volume recombination). The kinetic model provides an understanding of the impact of chamber geometry, gas flow rates, pressure and temperature on fluorine recombination. The plasma-kinetic model is validated by comparing model predictions (percentage F atom density) with experimental results (etch rates)

  8. Simulation Study of an Extended Density DC Glow Toroidal Plasma Source

    International Nuclear Information System (INIS)

    Granda-Gutierrez, E. E.; Piedad-Beneitez, A. de la; Lopez-Callejas, R.; Godoy-Cabrera, O. G.; Benitez-Read, J. S.; Pacheco-Sotelo, J. O.; Pena-Eguiluz, R.; Mercado-Cabrera, A.; Valencia A, R.; Barocio, S. R.

    2006-01-01

    Conventional wisdom assigns the DC glow discharge regime to plasma currents below ∼500 mA values, beyond which the discharge falls into the anomalous glow and the turbulent arc regimes. However, we have found evidence that, during toroidal discharges, this barrier can be ostensibly extended up to 800 mA. Thus, a computer simulation has been applied to the evolution of the main electrical characteristics of such a glow discharge plasma in a toroidal vessel in order to design and construct a respective voltage/current controlled source. This should be able to generate a DC plasma in the glow regime with which currents in the range 10-3-100 A can be experimented and 109-1010 cm-3 plasma densities can be achieved to PIII optimization purposes. The plasma is modelled as a voltage-controlled current source able to be turned on whenever the breakdown voltage is reached across the gap between the anode and the vessel wall. The simulation outcome fits well our experimental measurements showing that the plasma current obeys power laws that are dependent on the power current and other control variables such as the gas pressure

  9. Beam plasma 14 MeV neutron source for fusion materials development

    International Nuclear Information System (INIS)

    Ravenscroft, D.; Bulmer, D.; Coensgen, F.; Doggett, J.; Molvik, A.; Souza, P.; Summers, L.; Williamson, V.

    1991-09-01

    The conceptual engineering design and expected performance for a 14 MeV DT neutron source is detailed. The source would provide an intense neutron flux for accelerated testing of fusion reactor materials. The 150-keV neutral beams inject energetic deuterium atoms, that ionize, are trapped, then react with a warm (200 eV), dense tritium target plasma. This produces a neutron source strength of 3.6 x 10 17 n/sec for a neutron power density at the plasma edge of 5--10 MW/m 2 . This is several times the ∼2 MW/m 2 anticipated at the first wall of fusion reactors. This high flux provides accelerated end-of-life tests of 1- to 2-year duration, thus making materials development possible. The modular design of the source and the facilities are described

  10. Experimental benchmark of the NINJA code for application to the Linac4 H- ion source plasma

    Science.gov (United States)

    Briefi, S.; Mattei, S.; Rauner, D.; Lettry, J.; Tran, M. Q.; Fantz, U.

    2017-10-01

    For a dedicated performance optimization of negative hydrogen ion sources applied at particle accelerators, a detailed assessment of the plasma processes is required. Due to the compact design of these sources, diagnostic access is typically limited to optical emission spectroscopy yielding only line-of-sight integrated results. In order to allow for a spatially resolved investigation, the electromagnetic particle-in-cell Monte Carlo collision code NINJA has been developed for the Linac4 ion source at CERN. This code considers the RF field generated by the ICP coil as well as the external static magnetic fields and calculates self-consistently the resulting discharge properties. NINJA is benchmarked at the diagnostically well accessible lab experiment CHARLIE (Concept studies for Helicon Assisted RF Low pressure Ion sourcEs) at varying RF power and gas pressure. A good general agreement is observed between experiment and simulation although the simulated electron density trends for varying pressure and power as well as the absolute electron temperature values deviate slightly from the measured ones. This can be explained by the assumption of strong inductive coupling in NINJA, whereas the CHARLIE discharges show the characteristics of loosely coupled plasmas. For the Linac4 plasma, this assumption is valid. Accordingly, both the absolute values of the accessible plasma parameters and their trends for varying RF power agree well in measurement and simulation. At varying RF power, the H- current extracted from the Linac4 source peaks at 40 kW. For volume operation, this is perfectly reflected by assessing the processes in front of the extraction aperture based on the simulation results where the highest H- density is obtained for the same power level. In surface operation, the production of negative hydrogen ions at the converter surface can only be considered by specialized beam formation codes, which require plasma parameters as input. It has been demonstrated that

  11. Railguns and plasma accelerators: arc armatures, pulse power sources and US patents

    Energy Technology Data Exchange (ETDEWEB)

    Friedrich, O.M. Jr.

    1980-11-01

    Railguns and plasma accelerators have the potential for use in many basic and applied research projects, such as in creating high-pressures for equation-of-state studies and in impact fusion. A brief review of railguns and plasma accelerators with references is presented. Railgun performance is critically dependent on armature operation. Plasma arc railgun armatures are addressed. Pulsed power supplies for multi-stage railguns are considered. This includes brief comments on the compensated pulsed alternator, or compulsator, rotating machinery, and distributed energy sources for railguns. References are given at the end of each section. Appendix A contains a brief review of the US Patents on multi-staging techniques for electromagnetic accelerators, plasma propulsion devices, and electric guns.

  12. Railguns and plasma accelerators: arc armatures, pulse power sources and US patents

    International Nuclear Information System (INIS)

    Friedrich, O.M. Jr.

    1980-11-01

    Railguns and plasma accelerators have the potential for use in many basic and applied research projects, such as in creating high-pressures for equation-of-state studies and in impact fusion. A brief review of railguns and plasma accelerators with references is presented. Railgun performance is critically dependent on armature operation. Plasma arc railgun armatures are addressed. Pulsed power supplies for multi-stage railguns are considered. This includes brief comments on the compensated pulsed alternator, or compulsator, rotating machinery, and distributed energy sources for railguns. References are given at the end of each section. Appendix A contains a brief review of the US Patents on multi-staging techniques for electromagnetic accelerators, plasma propulsion devices, and electric guns

  13. First results from the Los Alamos plasma source ion implantation experiment

    International Nuclear Information System (INIS)

    Rej, D.J.; Faehl, R.J.; Gribble, R.J.; Henins, I.; Kodali, P.; Nastasi, M.; Reass, W.A.; Tesmer, J.; Walter, K.C.; Wood, B.P.; Conrad, J.R.; Horswill, N.; Shamim, M.; Sridharan, K.

    1993-01-01

    A new facility is operational at Los Alamos to examine plasma source ion implantation on a large scale. Large workpieces can be treated in a 1.5-m-diameter, 4.6-m-long plasma vacuum chamber. Primary emphasis is directed towards improving tribological properties of metal surfaces. First experiments have been performed at 40 kV with nitrogen plasmas. Both coupons and manufactured components, with surface areas up to 4 m 2 , have been processed. Composition and surface hardness of implanted materials are evaluated. Implant conformality and dose uniformity into practical geometries are estimated with multidimensional particle-in-cell computations of plasma electron and ion dynamics, and Monte Carlo simulations of ion transport in solids

  14. On electromagnetic wave propagation through a plasma sheath produced by a moving ionization source

    International Nuclear Information System (INIS)

    Semenova, V.I.

    1977-01-01

    Features of the interaction of electromagnetic waves are considered with a nonstationary plasma layer of a finite thickness, produced in an immovable gas by a movable ionization source. It is shown that a static magnetic field excited on the ionization front in build-up of electrons produced in the incident wave field reemits the energy to the electromagnetic wave during the plasma relaxation caused by recombination processes. As a result the electromagnetic wave of a finite amplitude may propagate behind the nonstationary layer of an ''opaque'' (ωsub(p)sup(2)>>ωsub(urc)sup((0))sup(2)) plasma as distinct from the layer of a movable stationary plasma with the same parameters

  15. Microwave frequency sweep interferometer for plasma density measurements in ECR ion sources: Design and preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Torrisi, Giuseppe [INFN - Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); University Mediterranea of Reggio Calabria, Reggio Calabria (Italy); Mascali, David; Neri, Lorenzo; Leonardi, Ornella; Celona, Luigi; Castro, Giuseppe; Agnello, Riccardo; Caruso, Antonio; Passarello, Santi; Longhitano, Alberto; Gammino, Santo [INFN - Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); Sorbello, Gino [INFN - Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); University of Catania, Catania, Italy and INFN-LNS, Catania (Italy); Isernia, Tommaso [University Mediterranea of Reggio Calabria, Reggio Calabria (Italy)

    2016-02-15

    The Electron Cyclotron Resonance Ion Sources (ECRISs) development is strictly related to the availability of new diagnostic tools, as the existing ones are not adequate to such compact machines and to their plasma characteristics. Microwave interferometry is a non-invasive method for plasma diagnostics and represents the best candidate for plasma density measurement in hostile environment. Interferometry in ECRISs is a challenging task mainly due to their compact size. The typical density of ECR plasmas is in the range 10{sup 11}–10{sup 13} cm{sup −3} and it needs a probing beam wavelength of the order of few centimetres, comparable to the chamber radius. The paper describes the design of a microwave interferometer developed at the LNS-INFN laboratories based on the so-called “frequency sweep” method to filter out the multipath contribution in the detected signals. The measurement technique and the preliminary results (calibration) obtained during the experimental tests will be presented.

  16. Projected configuration of a coal-fired district heating source on the basis of comparative technical-economical optimization analysis

    Directory of Open Access Journals (Sweden)

    Tańczuk Mariusz

    2017-01-01

    Full Text Available District heating technologies should be efficient, effective and environmentally friendly. The majority of the communal heating systems in Poland produce district hot water in coal-fired boilers. A large number of them are considerably worn out, low-efficient in the summer time and will not comply with forthcoming regulations. One of the possible solution for such plants is repowering with new CHP systems or new boilers fuelled with fuels alternative to coal. Optimisation analysis of the target configuration of municipal heat generating plant is analysed in the paper. The work concerns repowering the existing conventional heat generating plant according to eight different scenarios of the plant configuration meeting technical and environmental requirements forecasted for the year of 2035. The maximum demand for heat of the system supplied by the plant is 185 MW. Taking into account different technical configurations on one side, and different energy and fuel prices on the other side, the comparative cost-benefits analysis of the assumed scenarios has been made. The basic economical index NPV (net present value has been derived for each analysed scenario and the results have been compared and discussed. It was also claimed that the scenario with CHP based on ICE engines is optimal.

  17. Projected configuration of a coal-fired district heating source on the basis of comparative technical-economical optimization analysis

    Science.gov (United States)

    Tańczuk, Mariusz; Radziewicz, Wojciech; Olszewski, Eligiusz; Skorek, Janusz

    2017-10-01

    District heating technologies should be efficient, effective and environmentally friendly. The majority of the communal heating systems in Poland produce district hot water in coal-fired boilers. A large number of them are considerably worn out, low-efficient in the summer time and will not comply with forthcoming regulations. One of the possible solution for such plants is repowering with new CHP systems or new boilers fuelled with fuels alternative to coal. Optimisation analysis of the target configuration of municipal heat generating plant is analysed in the paper. The work concerns repowering the existing conventional heat generating plant according to eight different scenarios of the plant configuration meeting technical and environmental requirements forecasted for the year of 2035. The maximum demand for heat of the system supplied by the plant is 185 MW. Taking into account different technical configurations on one side, and different energy and fuel prices on the other side, the comparative cost-benefits analysis of the assumed scenarios has been made. The basic economical index NPV (net present value) has been derived for each analysed scenario and the results have been compared and discussed. It was also claimed that the scenario with CHP based on ICE engines is optimal.

  18. Boundary layer plasmas as a source for high-latitude, early afternoon, auroral arcs

    International Nuclear Information System (INIS)

    Lundin, R.; Evans, D.S.

    1985-02-01

    Simultaneous measurements of hot boundary layer plasma from PROGNOZ-7 and particle precipitation from the TIROS/NOAA satellite in nearly magnetically conjugate regions have been used to study the dynamo process responsible for the formation of high latitude, early afternoon, auroral arcs. Characteristic for the PROGNOZ-7 observations in the dayside boundary layer at high latitudes is the frequent occurrence of regions with injected magnetosheath plasma embedded in a 'halo' of antisunward flowing magnetosphere plasma. The injected magnetosheath plasma have several features which indicate that it also acts as a local source of EMF in the boundary layer. The process resembles that of a local MHD dynamo driven by the excess drift velocity of the injected magnetosheath plasma relative to the background magnetospheric plasma. The dynamo region is capable of driving fielc-aligned currents that couple to the ionosphere, where the upward current is associated with the high latitude auroral arcs. We demonstrate that the large-scale morphology as well as the detailed data intercomparison between PROGNOZ-7 and TIROS-N both agree well with a local injection of magnetosheath plasma into the dayside boundary layer as the main dynamo process powering the high-latitude, early afternoon auroral arcs. (Author)

  19. The inductively coupled plasma as a source for the measurement of fundamental spectroscopic constants

    International Nuclear Information System (INIS)

    Farnsworth, P.B.

    1993-01-01

    Inductively coupled plasmas (ICPs) are stable, robust sources for the generation of spectra from neutral and singly ionized atoms. They are used extensively for analytical spectrometry, but have seen limited use for the measurement of fundamental spectroscopic constants. Several properties of the ICP affect its suitability for such fundamental measurements. They include: spatial structure, spectral background, noise characteristics, electron densities and temperatures, and the state of equilibrium in the plasma. These properties are particularly sensitive to the means by which foreign atoms are introduced into the plasma. With some departures from the operating procedures normally used in analytical measurements, the ICP promise to be a useful source for the measurement of fundamental atomic constants. (orig.)

  20. First plasma of the A-PHOENIX electron cyclotron resonance ion source

    International Nuclear Information System (INIS)

    Thuillier, T.; Lamy, T.; Latrasse, L.; Angot, J.

    2008-01-01

    A-PHOENIX is a new compact hybrid electron cyclotron resonance ion source using a large permanent magnet hexapole (1.92 T at the magnet surface) and high temperature superconducting Solenoids (3 T) to make min-vertical bar B vertical bar structure suitable for 28 GHz cw operation. The final assembly of the source was achieved at the end of June 2007. The first plasma of A-PHOENIX at 18 GHz was done on the 16th of August, 2007. The technological specificities of A-PHOENIX are presented. The large hexapole built is presented and experimental magnetic measurements show that it is nominal with respect to simulation. A fake plasma chamber prototype including thin iron inserts showed that the predicted radial magnetic confinement can be fulfilled up to 2.15 T at the plasma chamber wall. Scheduled planning of experiments until the end of 2008 is presented

  1. Quasi-steady state, low current behaviour of a magnetized coaxial plasma source

    International Nuclear Information System (INIS)

    Gray, Travis K; Mayo, Robert M; Bourham, Mohamed A

    2005-01-01

    The Coaxial Plasma Source-1 facility (Mayo R M et al 1995 Plasma Sources Sci. Technol. 4 47) was modified from a short pulse, high current (SPHC) pulse forming network (PFN) with very low inductance (∼200 nH) to a large inductance ladder circuit. This modification allows for a longer, flat top gun current pulse that eliminates the under-damped, sinusoidal behaviour of the gun current with consequent interruptions in plasma parameters. The new PFN was designed to produce a current waveform for a much longer period (∼1 ms). As a consequence of increasing the pulse length, the magnitude of the gun current was reduced as no additional energy storage was added to the PFN. The characterization of the electrical and plasma behaviour of the experiment operated with the long pulse, low current (LPLC) PFN is presented. The gun currents produced by the LPLC PFN are approximately one-fifth in magnitude of the gun currents produced by the SPHC PFN. Axial plasma parameters were measured near the muzzle of the plasma source, and electron densities were found to range from 1 x 10 19 m -3 to 7 x 10 19 m -3 depending upon the axial location. These values are approximately 1-2 orders of magnitude less than the electron densities produced by the SPHC PFN at the same locations. Electron temperatures range from 30 to 60 eV at these locations and are very similar to those produced by the SPHC PFN. A resistive MHD model was applied as an order estimate of the plasma resistivity and demonstrates reasonable agreement with measured values of the magnetized coaxial gun resistance

  2. Quasi-steady state, low current behaviour of a magnetized coaxial plasma source

    Energy Technology Data Exchange (ETDEWEB)

    Gray, Travis K; Mayo, Robert M; Bourham, Mohamed A [Department of Nuclear Engineering, North Carolina State University, Raleigh, NC 27695-7909 (United States)

    2005-11-15

    The Coaxial Plasma Source-1 facility (Mayo R M et al 1995 Plasma Sources Sci. Technol. 4 47) was modified from a short pulse, high current (SPHC) pulse forming network (PFN) with very low inductance ({approx}200 nH) to a large inductance ladder circuit. This modification allows for a longer, flat top gun current pulse that eliminates the under-damped, sinusoidal behaviour of the gun current with consequent interruptions in plasma parameters. The new PFN was designed to produce a current waveform for a much longer period ({approx}1 ms). As a consequence of increasing the pulse length, the magnitude of the gun current was reduced as no additional energy storage was added to the PFN. The characterization of the electrical and plasma behaviour of the experiment operated with the long pulse, low current (LPLC) PFN is presented. The gun currents produced by the LPLC PFN are approximately one-fifth in magnitude of the gun currents produced by the SPHC PFN. Axial plasma parameters were measured near the muzzle of the plasma source, and electron densities were found to range from 1 x 10{sup 19} m{sup -3} to 7 x 10{sup 19} m{sup -3} depending upon the axial location. These values are approximately 1-2 orders of magnitude less than the electron densities produced by the SPHC PFN at the same locations. Electron temperatures range from 30 to 60 eV at these locations and are very similar to those produced by the SPHC PFN. A resistive MHD model was applied as an order estimate of the plasma resistivity and demonstrates reasonable agreement with measured values of the magnetized coaxial gun resistance.

  3. Use of a new ion-detector in the study of the jet plasma injected into a pulsed magnetic mirror configuration (deca I)

    International Nuclear Information System (INIS)

    Renaud, C.

    1963-01-01

    The study of a high sensitivity ion detector coupled to an electrostatic analyser has permitted a large investigation of the plasma jet injected into a pulsed magnetic mirror configuration. In this detector the positive ions are accelerated through a potential of 30 kV; they strike a metallic target, on which they produce secondary electrons; these, in turn, are accelerated onto a plastic scintillator. The light pulses are detected with a photomultiplier. The gain of this device is about 10 7 . If we make an admission of air into the vacuum system and again we make vacuum, the gain is not modified, since no special activated surfaces are situated in the detector. (author) [fr

  4. [Experimental investigation of laser plasma soft X-ray source with gas target].

    Science.gov (United States)

    Ni, Qi-liang; Gong, Yan; Lin, Jing-quan; Chen, Bo; Cao, Jian-lin

    2003-02-01

    This paper describes a debris-free laser plasma soft X-ray source with a gas target, which has high operating frequency and can produce strong soft X-ray radiation. The valve of this light source is drived by a piezoelectrical ceramic whose operating frequency is up to 400 Hz. In comparison with laser plasma soft X-ray sources using metal target, the light source is debris-free. And it has higher operating frequency than gas target soft X-ray sources whose nozzle is controlled by a solenoid valve. A channel electron multiplier (CEM) operating in analog mode is used to detect the soft X-ray generated by the laser plasma source, and the CEM's output is fed to to a charge-sensitive preamplifier for further amplification purpose. Output charges from the CEM are proportional to the amplitude of the preamplifier's output voltage. Spectra of CO2, Xe and Kr at 8-14 nm wavelength which can be used for soft X-ray projection lithography are measured. The spectrum for CO2 consists of separate spectral lines originate mainly from the transitions in Li-like and Be-like ions. The Xe spectrum originating mainly from 4d-5f, 4d-4f, 4d-6p and 4d-5p transitions in multiply charged xenon ions. The spectrum for Kr consists of separate spectral lines and continuous broad spectra originating mainly from the transitions in Cu-, Ni-, Co- and Fe-like ions.

  5. Energization of the Ring Current through Convection of Substorm Enhancements of the Plasma Sheet Source.

    Science.gov (United States)

    Menz, A.; Kistler, L. M.; Mouikis, C.; Spence, H. E.; Henderson, M. G.; Matsui, H.

    2017-12-01

    It has been shown that electric field strength and night-side plasma sheet density are the two best predictors of the adiabatic energy gain of the ring current during geomagnetic storms (Liemohn and Khazanov, 2005). While H+ dominates the ring current during quiet times, O+ can contribute substantially during geomagnetic storms. Substorm activity provides a mechanism to enhance the energy density of O+ in the plasma sheet during geomagnetic storms, which is then convected adiabatically into the inner-magnetosphere. Using the Van Allen Probes data in the the plasma sheet source region (defined as L>5.5 during storms) and the inner magnetosphere, along with LANL-GEO data to identify substorm injection times, we show that adiabatic convection of O+ enhancements in the source region can explain the observed enhancements in the inner magnetosphere. We use the UNH-IMEF electric field model to calculate drift times from the source region to the inner magnetosphere to test whether enhancements in the inner-magnetosphere can be explained by dipolarization driven enhancements in the plasma sheet source hours before.

  6. Study of the general plasma characteristics of a high power multifilament ion source

    International Nuclear Information System (INIS)

    Schoenberg, K.F.

    1979-09-01

    A general assessment of the steady state and time dependent plasma properties which characterize a high power multifilament ion source is presented. Steady state measurements, obtained via a pulsed electrostatic probe data acquisition system, are described. Fluctuation measurements, obtained via a broadband digital spectral analysis system, are also given

  7. Increase of plasma ion source efficiency utilizing collisions of the second kind

    International Nuclear Information System (INIS)

    Winkler, H.

    1979-01-01

    It is experimentally found that the efficiency of a plasma ion source for use in an electromagnetic separator can be increased under appropriate operating conditions utilizing collisions of the second kind, of a proper gas is additionally introduced into the arc chamber containing atoms with metastable excited levels. (author)

  8. An accelerated beam-plasma neutron/proton source and early application of a fusion plasma

    International Nuclear Information System (INIS)

    Ohnishi, M.; Yoshikawa, K.; Yamamoto, Y.; Hoshino, C.; Masuda, K.; Miley, G.; Jurczyk, B.; Stubbers, R.; Gu, Y.

    1999-01-01

    We measured the number of the neutrons and protons produced by D-D reactions in an accelerated beam-plasma fusion and curried out the numerical simulations. The linear dependence of the neutron yield on a discharge current indicates that the fusion reactions occur between the background gas and the fast particles. i.e. charge exchanged neutrals and accelerated ions. The neutron yield divided by (fusion cross section x ion current x neutral gas pressure) still possesses the dependence of the 1.2 power of discharge voltage. which shows the fusion reactions are affected by the electrostatic potential built-up in the center. The measured proton birth profiles suggest the existence of a double potential well, which is supported by the numerical simulations. (author)

  9. Plasma source by microwaves: design description; Fuente de plasma por microondas: descripcion de diseno

    Energy Technology Data Exchange (ETDEWEB)

    Camps, E; Olea, O; Andrade, R; Anguiano, G

    1992-03-15

    The design of a device for the formation of a plasma with densities of the order of 10{sup 12} cm{sup -} {sup 3} and low temperatures (T{sub e} {approx} 40 eV) is described. For such purpose it was carried out in the device a microwave discharge (f{sub o} = 2.45 GHz) in a resonator of high Q factor, immersed in a static external magnetic field. The device worked in the regime {omega}{sub ce} {<=} {omega}{sub o}/2 ({omega}{sub ce}- cyclotron frequency of the electrons, ({omega}{sub o} = 2 {pi} f{sub o}) where is possible the excitement of non lineal phenomena of waves transformation. (Author)

  10. Dependence of proton beam polarization on ion source transition configurations; Determination de la polarisation du faisceau de protons pour les quatre configurations des transitions de la source d`ions

    Energy Technology Data Exchange (ETDEWEB)

    Arvieux, J.; Ausset, P.; Ball, J.; Beauvais, P.Y.; Bedfer, Y.; Chamouard, P.A.; Fontaine, J.M.; Kunne, R.; Lagniel, J.M.; Sans, J.L. [Laboratoire National Saturne - Centre d`Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France); Allgower, Ch.; Kasprzyk, T.E.; Spinka, H.M. [ANL-HEP, Argonne (United States); Bystricky, J.; Lehar, F.; Lesquen, A. de [CEA Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France). Dept. d`Astrophysique, de la Physique des Particules, de la Physique Nucleaire et de l`Instrumentation Associee; Demiere, Ph.; Rapin, D.; Teglia, A. [Geneva Univ. (Switzerland). Dept. de Physique Nucleaire et Corpusculaire; Janout, Z. [Czech Technical Univ., Prague (Czech Republic). Faculty of Civil Engineering; Kalinnikov, V.A.; Khachaturov, B.A.; Popov, A.A. [Laboratory of Nuclear Problems, JINR, Moscow (Russian Federation); Prokofiev, A.N.; Vikhrov, V.V.; Zhdanov, A.A. [Nuclear Physics Inst., St. Petersburg (Russian Federation)

    1997-12-31

    Considerable anomalies were observed in recorded pp elastic scattering spin dependent data at several proton beam energies at SATURNE II. These results suggested that the discrepancies are related to the polarized ion source. In order to understand the observed effects, the proton beam polarizations for each ion source state were determined separately. Convenient procedures, allowing to determine the beam polarization from a beam-line polarimeter are presented. Two distinct experiments are necessary for this purpose. In the first one the LEFT-RIGHT instrumental asymmetry of the beam polarimeter arms is determined. In the second one this correction factor is applied to asymmetries measured with the beam from the polarized ion source in different polarization states. Both experiments determined the scattering asymmetries for all four polarized source states as functions of different source parameters. The measurements were carried out at the proton beam kinetic energy 0.80 GeV, where the pp elastic scattering analyzing power is at its maximum. Results show that the so called `unpolarized states` of the source are polarized, whereas the absolute values of the beam polarizations in `polarized states` are equal. It was observed that the hexapole lens of the ion source provides some beam polarization in the absence of any transition. The beam polarization as function of the hexapole current, of the transition efficiencies and of the rotation solenoid current has been studied. It is also shown, how one way obtain a strictly unpolarized beam using the polarized source only. The results obtained with the SATURNE II ion source HYPERION may be also valid for other accelerators and sources. (authors) 10 refs.

  11. Improved density profile measurements in the C-2U advanced beam-driven Field-Reversed Configuration (FRC) plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Beall, M., E-mail: mbeall@trialphaenergy.com; Deng, B. H.; Gota, H. [Tri Alpha Energy, Inc., P.O. Box 7010, Rancho Santa Margarita, California 92688 (United States)

    2016-11-15

    In the prior C-2 experiment, electron density was measured using a two-color 6-chord CO{sub 2}/HeNe interferometer. Analysis shows that high-frequency common mode phase noise can be reduced by a factor of 3 by constructing a reference chord. In the system upgrade from C-2 to C-2U a 4-chord far-infrared laser interferometer was developed, which demonstrated superior sensitivity (1 × 10{sup 16} m{sup −2} at >1 MHz bandwidth) and solved the under spatial sampling issue of the C-2 interferometer system. Improved density-profile measurement results are presented in this paper, including evidence of fast-ion modified density profile and stabilization of the n = 1 plasma wobble mode.

  12. Investigation of PCDD/F emissions from mobile source diesel engines: impact of copper zeolite SCR catalysts and exhaust aftertreatment configurations.

    Science.gov (United States)

    Liu, Z Gerald; Wall, John C; Barge, Patrick; Dettmann, Melissa E; Ottinger, Nathan A

    2011-04-01

    This study investigated the impact of copper zeolite selective catalytic reduction (SCR) catalysts and exhaust aftertreatment configurations on the emissions of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) from mobile source diesel engines. Emissions of PCDD/Fs, reported as the weighted sum of 17 congeners called the toxic equivalency quotient (TEQ), were measured using a modified EPA Method 0023A in the absence and presence of exhaust aftertreatment. Engine-out emissions were measured as a reference, while aftertreatment configurations included various combinations of diesel oxidation catalyst (DOC), diesel particulate filter (DPF), Cu-zeolite SCR, Fe-zeolite SCR, ammonia oxidation catalyst (AMOX), and aqueous urea dosing. In addition, different chlorine concentrations were evaluated. Results showed that all aftertreatment configurations reduced PCDD/F emissions in comparison to the engine-out reference, consistent with reduction mechanisms such as thermal decomposition or combined trapping and hydrogenolysis reported in the literature. Similarly low PCDD/F emissions from the DOC-DPF and the DOC-DPF-SCR configurations indicated that PCDD/F reduction primarily occurred in the DOC-DPF with no noticeable contribution from either the Cu- or Fe-zeolite SCR systems. Furthermore, experiments performed with high chlorine concentration provided no evidence that chlorine content has an impact on the catalytic synthesis of PCDD/Fs for the chlorine levels investigated in this study.

  13. Design and fabrication of a large rectangular magnetic cusp plasma source for high intensity neutral beam injectors

    International Nuclear Information System (INIS)

    Biagi, L.A.; Berkner, K.H.; Ehlers, K.W.; Paterson, J.A.; Porter, J.R.

    1979-11-01

    The design and fabrication techniques for a large, rectangular magnetic bucket plasma source are described. This source is compatible with the accelerator structures for the TFTR and DIII neutral-beam systems

  14. Suppression of the e- coextracted from a Penning surface-plasma H-source

    International Nuclear Information System (INIS)

    Smith, V.H.; Allison, P.

    1992-01-01

    The ratio of electrons to negative ions extracted from Penning surface-plasma sources (SPS) such as the 8X source is low even before any steps are taken to suppress the electrons. For the 8X source the e - /H - ratio is typically four or five to one for H - operation and nine to one for D - operation. Because the coextracted e - present a power-loading problem to the 8X-source extraction system, methods to dissipate and/or reduce the power in the e - beam must be developed before extracting a dc H - or D - beam. Thus, we conducted this study to determine whether a collar installed in the near-extraction region of the 8X source suppresses the electrons extracted from that source. (Author) 8 refs., 6 figs

  15. High average power, highly brilliant laser-produced plasma source for soft X-ray spectroscopy.

    Science.gov (United States)

    Mantouvalou, Ioanna; Witte, Katharina; Grötzsch, Daniel; Neitzel, Michael; Günther, Sabrina; Baumann, Jonas; Jung, Robert; Stiel, Holger; Kanngiesser, Birgit; Sandner, Wolfgang

    2015-03-01

    In this work, a novel laser-produced plasma source is presented which delivers pulsed broadband soft X-radiation in the range between 100 and 1200 eV. The source was designed in view of long operating hours, high stability, and cost effectiveness. It relies on a rotating and translating metal target and achieves high stability through an on-line monitoring device using a four quadrant extreme ultraviolet diode in a pinhole camera arrangement. The source can be operated with three different laser pulse durations and various target materials and is equipped with two beamlines for simultaneous experiments. Characterization measurements are presented with special emphasis on the source position and emission stability of the source. As a first application, a near edge X-ray absorption fine structure measurement on a thin polyimide foil shows the potential of the source for soft X-ray spectroscopy.

  16. A Novel Process Configuration for Anaerobic Digestion of Source-Sorted Household Waste Using Hyper-Thermophilic Post-Treatment

    DEFF Research Database (Denmark)

    Hartmann, H.; Ahring, Birgitte Kiær

    2005-01-01

    A novel reactor configuration was investigated for anaerobic digestion (AD) of the organic fraction of municipal solid waste (OFMSW). An anaerobic hyper-thermophilic (68°C) reactor R68 was implemented as a post–treatment step for the effluent of a thermophilic reactor R1 (55°C) in order to enhance...... hydrolysis of recalcitrant organic matter, improve sanitation and ease the stripping of ammonia from the reactor. The efficiency of the combined system was studied in terms of methane yield, volatile solids (VS) reduction and volatile fatty acid (VFA) production at different hydraulic retention times (HRT...

  17. Biological stimulation of the Human skin applying health promoting light and plasma sources

    Energy Technology Data Exchange (ETDEWEB)

    Awakowicz, P.; Bibinov, N. [Center for Plasma Science and Technology, Ruhr-University, Bochum (Germany); Born, M.; Niemann, U. [Philips Research, Aachen (Germany); Busse, B. [Zell-Kontakt GmbH, Noerten-Hardenberg (Germany); Gesche, R.; Kuehn, S.; Porteanu, H.E. [Ferdinand-Braun-Institut fuer Hoechstfrequenztechnik, Berlin (Germany); Helmke, A. [University of Applied Sciences and Arts, Goettingen (Germany); Kaemling, A.; Wandke, D. [CINOGY GmbH, Duderstadt (Germany); Kolb-Bachofen, V.; Liebmann, J. [Institute for Immunobiology, Heinrich-Heine University, Duesseldorf (Germany); Kovacs, R.; Mertens, N.; Scherer, J. [Aurion Anlagentechnik GmbH, Seligenstadt (Germany); Oplaender, C.; Suschek, C. [Clinic for Plastic Surgery, University Clinic, Aachen (Germany); Vioel, W. [Laser-Laboratorium, Goettingen (Germany); University of Applied Sciences and Arts, Goettingen (Germany)

    2009-10-15

    In the frame of BMBF project ''BioLiP'', new physical treatment techniques aiming at medical treatment of the human skin have been developed. The acronym BioLiP stands for ''Desinfektion, Entkeimung und biologische Stimulation der Haut durch gesundheitsfoerdernde Licht- und Plasmaquellen'' (Disinfection, germ reduction and biological stimulation of the human skin by health promoting light and plasma sources). A source applying a low-temperature dielectric barrier discharge plasma (DBD) has been investigated on its effectiveness for skin disinfection and stimulation of biological material. Alternatively an atmospheric plasma source consisting of a microwave resonator combined with a solid state power oscillator has been examined. This concept which allows for a compact and efficient design avoiding external microwave power supply and matching units has been optimized with respect to nitrogen monoxide (NO) production in high yields. In both cases various application possibilities in the medical and biological domain are opened up. Light sources in the visible spectral range have been investigated with respect to the proliferation of human cell types. Intensive highly selective blue light sources based on LED technology can slow down proliferation rates without inducing toxic effects which offers new opportunities for treatments of so-called hyperproliferative skin conditions (e.g. with psoriasis or in wound healing) using UV-free light. (copyright 2009 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  18. Broadband frequency ECR ion source concepts with large resonant plasma volumes

    International Nuclear Information System (INIS)

    Alton, G.D.

    1995-01-01

    New techniques are proposed for enhancing the performances of ECR ion sources. The techniques are based on the use of high-power, variable-frequency, multiple-discrete-frequency, or broadband microwave radiation, derived from standard TWT technology, to effect large resonant ''volume'' ECR sources. The creation of a large ECR plasma ''volume'' permits coupling of more power into the plasma, resulting in the heating of a much larger electron population to higher energies, the effect of which is to produce higher charge state distributions and much higher intensities within a particular charge state than possible in present forms of the ECR ion source. If successful, these developments could significantly impact future accelerator designs and accelerator-based, heavy-ion-research programs by providing multiply-charged ion beams with the energies and intensities required for nuclear physics research from existing ECR ion sources. The methods described in this article can be used to retrofit any ECR ion source predicated on B-minimum plasma confinement techniques

  19. Plasma studies of the permanent magnet electron cyclotron resonance ion source at Peking University.

    Science.gov (United States)

    Ren, H T; Peng, S X; Xu, Y; Zhao, J; Lu, P N; Chen, J; Zhang, A L; Zhang, T; Guo, Z Y; Chen, J E

    2014-02-01

    At Peking University (PKU) we have developed several 2.45 GHz Permanent Magnet Electron Cyclotron Resonance ion sources for PKUNIFTY, SFRFQ, Coupled RFQ&SFRFQ, and Dielectric-Wall Accelerator (DWA) projects (respectively, 50 mA of D(+), 10 mA of O(+), 10 mA of He(+), and 50 mA of H(+)). In order to improve performance of these ion sources, it is necessary to better understand the principal factors that influence the plasma density and the atomic ion fraction. Theoretical analysis about microwave transmission and cut-off inside the discharge chamber were carried out to study the influence of the discharge chamber diameters. As a consequence, experimental studies on plasma density and ion fraction with different discharge chamber sizes have been carried out. Due to the difficulties in measuring plasma density inside the discharge chamber, the output beam current was measured to reflect the plasma density. Experimental results show that the plasma density increases to the maximum and then decreases significantly as the diameter changed from 64 mm to 30 mm, and the atomic ion fraction has the same tendency. The maximum beam intensity was obtained with the diameter of 35 mm, but the maximum atomic ion fraction with a diameter of 40 mm. The experimental results are basically accordant with the theoretical calculation. Details are presented in this paper.

  20. Plasma studies of the permanent magnet electron cyclotron resonance ion source at Peking University

    Energy Technology Data Exchange (ETDEWEB)

    Ren, H. T.; Peng, S. X., E-mail: sxpeng@pku.edu.cn; Xu, Y.; Zhao, J.; Lu, P. N.; Chen, J.; Zhang, A. L.; Zhang, T.; Guo, Z. Y.; Chen, J. E. [State Key Laboratory of Nuclear Physics and Technology, Institute of Heavy Ion Physics, Peking University, Beijing 100871 (China)

    2014-02-15

    At Peking University (PKU) we have developed several 2.45 GHz Permanent Magnet Electron Cyclotron Resonance ion sources for PKUNIFTY, SFRFQ, Coupled RFQ and SFRFQ, and Dielectric-Wall Accelerator (DWA) projects (respectively, 50 mA of D{sup +}, 10 mA of O{sup +}, 10 mA of He{sup +}, and 50 mA of H{sup +}). In order to improve performance of these ion sources, it is necessary to better understand the principal factors that influence the plasma density and the atomic ion fraction. Theoretical analysis about microwave transmission and cut-off inside the discharge chamber were carried out to study the influence of the discharge chamber diameters. As a consequence, experimental studies on plasma density and ion fraction with different discharge chamber sizes have been carried out. Due to the difficulties in measuring plasma density inside the discharge chamber, the output beam current was measured to reflect the plasma density. Experimental results show that the plasma density increases to the maximum and then decreases significantly as the diameter changed from 64 mm to 30 mm, and the atomic ion fraction has the same tendency. The maximum beam intensity was obtained with the diameter of 35 mm, but the maximum atomic ion fraction with a diameter of 40 mm. The experimental results are basically accordant with the theoretical calculation. Details are presented in this paper.

  1. The diagnostic neutral beam injector with arc-discharge plasma source on the TCV Tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Karpushov, Alexander N. [Ecole Polytechnique Federale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas, Association Euratom-Confederation Suisse, CH-1015 Lausanne (Switzerland)], E-mail: alexander.karpushov@epfl.ch; Andrebe, Yanis; Duval, Basil P.; Bortolon, Alessandro [Ecole Polytechnique Federale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas, Association Euratom-Confederation Suisse, CH-1015 Lausanne (Switzerland)

    2009-06-15

    The diagnostic neutral beam injector (DNBI) together with a charge exchange recombination spectroscopy (CXRS) system has been used on the TCV Tokamak as a diagnostic tool for local measurements of plasma ion temperature, velocity and carbon impurity density based on analysis of the beam induced impurity radiation emission since 2000. To improve the performance of the CXRS diagnostic, several upgrades of both the optical system and the neutral beam were performed. An increase of the plasma source size together with beam optimization in 2003 resulted in a twofold increase the beam current. The RF plasma generator was replaced by an arc-discharge plasma source together with a new ion optical system (IOS) in 2006 and subsequent beam optimization is presented herein. This was designed to increase the line brightness of the beam in the CXRS observation region without increasing of the injected power (to avoid plasma perturbation by the beam). The beam characteristics are measured by a multi-chord scanning of Doppler-shifted H{sub {alpha}} emission, thermal measurements on a movable calorimeter and visible optical measurements inside the Tokamak vessel.

  2. Yosemite conference on ionospheric plasma in the magnetosphere: sources, mechanisms and consequences, meeting report

    International Nuclear Information System (INIS)

    Gallagher, D.L.; Burch, J.L.; Klumpar, D.M.; Moore, T.E.; Waite, J.H. Jr.

    1987-02-01

    The sixth biennial Yosemite topical conference and the first as a Chapman Conference was held on February 3 to 6, 1986. Although the solar wind was once thought to dominate the supply of plasma in the Earth's magnetosphere, it is now thought that the Earth's ionosphere is a significant contributor. Polar wind and other large volume outflows of plasma have been seen at relatively high altitudes over the polar cap and are now being correlated with outflows found in the magnetotail. The auroral ion fountain and cleft ion fountain are examples of ionospheric sources of plasma in the magnetosphere, observed by the Dynamics Explorer 1 (DE 1) spacecraft. The conference was organized into six sessions: four consisting of prepared oral presentations, one poster session, and one session for open forum discussion. The first three oral sessions dealt separately with the three major topics of the conference, i.e., the sources, mechanisms, and consequences of ionospheric plasma in the magnetosphere. A special session of invited oral presentations was held to discuss extraterrestrial ionospheric/magnetospheric plasma processes. The poster session was extended over two evenings during which presenters discussed their papers on a one-on-one basis. The last session of the conferences was reserved for open discussions of those topics or ideas considered most interesting or controversial

  3. Modeling of Perpendicularly Driven Dual-Frequency Capacitively Coupled Plasma

    International Nuclear Information System (INIS)

    Wang Hongyu; Sun Peng; Zhao Shuangyun; Li Yang; Jiang Wei

    2016-01-01

    We analyzed perpendicularly configured dual-frequency (DF) capacitively coupled plasmas (CCP). In this configuration, two pairs of electrodes are arranged oppositely, and the discharging is perpendicularly driven by two radio frequency (RF) sources. Particle-in-cell/Monte Carlo (PIC/MC) simulation showed that the configuration had some advantages as this configuration eliminated some dual frequency coupling effects. Some variation and potential application of the discharging configuration is discussed briefly. (paper)

  4. Laser-produced plasma-extreme ultraviolet light source for next generation lithography

    International Nuclear Information System (INIS)

    Nishihara, Katsunobu; Nishimura, Hiroaki; Gamada, Kouhei; Murakami, Masakatsu; Mochizuki, Takayasu; Sasaki, Akira; Sunahara, Atsushi

    2005-01-01

    Extreme ultraviolet (EUV) lithography is the most promising candidate for the next generation lithography for the 45 nm technology node and below. EUV light sources under consideration use 13.5 nm radiations from multicharged xenon, tin and lithium ions, because Mo/Si multiplayer mirrors have high reflectivity at this wavelength. A review of laser-produced plasma (LPP) EUV light sources is presented with a focus on theoretical and experimental studies under the auspices of the Leading Project promoted by MEXT. We discuss three theoretical topics: atomic processes in the LPP-EUV light source, conversion efficiency from laser light to EUV light at 13.5 nm wave-length with 2% bound width, and fast ion spectra. The properties of EUV emission from tin and xenon plasmas are also shown based on experimental results. (author)

  5. Plasma focus sources: Supplement to the neutron resonance radiography workshop proceedings

    International Nuclear Information System (INIS)

    Nardi, V.; Brzosko, J.

    1989-01-01

    Since their discovery, plasma focus discharges have been recognized as very intense pulsed sources of deuterium-deuterium (D-D) or deuterium-tritium (D-T) fusion-reaction neutrons, with outstanding capabilities. Specifically, the total neutron emission/shot, YN, and the rate of neutron emission, Y/sub n/, of an optimized plasma focus (PF) are higher than the corresponding quantities observed in any other type of pinched discharge at the same level of powering energy W 0 . Recent developments have led to the concept and experimental demonstration of an Advanced Plasma Focus System (APF) that consists of a Mather-geometry plasma focus in which field distortion elements (FDEs) are inserted in the inter-electrode gap for increasing the neutron yield/shot, Y/sub n/. The FDE-induced redistribution of the plasma current increases Y/sub n/ by a factor ≅5-10 above the value obtained without FDEs under otherwise identical conditions of operation of the plasma focus. For example, an APF that is fed by a fast capacitor bank with an energy, W 0 = 6kJ, and voltage, V 0 = 16.5 kV provides Y/sub n/ /congruent/ 4 /times/ 10 9 D-D neutrons/shot (pure D 2 filling) and Y/sub n/ = 4 /times/ 10 11 D-T neutrons/shot (filling is 50% deuterium and 50% tritium). The FDE-induced increase of Y/sub n/ for fixed values of (W 0 , V 0 ), the observed scaling law Y/sub n/ /proportional to/ W 0 2 for optimized plasma focus systems, and our experience with neutron scattering in bulk objects lead us to the conclusion that we can use an APF as a source of high-intensity neutron pulses (10 14 n/pulse) in the field off neutron radiography (surface and bulk) with a nanosecond or millisecond time resolution

  6. Development and studies on a compact electron cyclotron resonance plasma source

    Science.gov (United States)

    Ganguli, A.; Tarey, R. D.; Arora, N.; Narayanan, R.

    2016-04-01

    It is well known that electron cyclotron resonance (ECR) produced plasmas are efficient, high-density plasma sources and have many industrial applications. The concept of a portable compact ECR plasma source (CEPS) would thus become important from an application point of view. This paper gives details of such a CEPS that is both portable and easily mountable on a chamber of any size. It uses a fully integrated microwave line operating at 2.45 GHz, up to 800 W, cw. The required magnetic field is produced by a set of suitably designed NdFeB ring magnets; the device has an overall length of  ≈60 cm and weighs  ≈14 kg including the permanent magnets. The CEPS was attached to a small experimental chamber to judge its efficacy for plasma production. In the pressure range of 0.5-10 mTorr and microwave power of  ≈400-500 W the experiments indicate that the CEPS is capable of producing high-density plasma (≈9  ×  1011-1012 cm-3) with bulk electron temperature in the range  ≈2-3 eV. In addition, a warm electron population with density and temperature in the range ≈7  ×  108-109 cm-3 and  ≈45-80 eV, respectively has been detected. This warm population plays an important role at high pressures in maintaining the high-density plasma, when plasma flow from the CEPS into the test chamber is strongly affected.

  7. Generation of plasma X-ray sources via high repetition rate femtosecond laser pulses

    Science.gov (United States)

    Baguckis, Artūras; Plukis, Artūras; Reklaitis, Jonas; Remeikis, Vidmantas; Giniūnas, Linas; Vengris, Mikas

    2017-12-01

    In this study, we present the development and characterization of Cu plasma X-ray source driven by 20 W average power high repetition rate femtosecond laser in ambient atmosphere environment. The peak Cu- Kα photon flux of 2.3 × 109 photons/s into full solid angle is demonstrated (with a process conversion efficiency of 10-7), using pulses with peak intensity of 4.65 × 1014 W/cm2. Such Cu- Kα flux is significantly larger than others found in comparable experiments, performed in air environment. The effects of resonance plasma absorption process, when optimized, are shown to increase measured flux by the factor of 2-3. The relationship between X-ray photon flux and plasma-driving pulse repetition rate is quasi-linear, suggesting that fluxes could further be increased to 1010 photons/s using even higher average powers of driving radiation. These results suggest that to fully utilize the potential of high repetition rate laser sources, novel target material delivery systems (for example, jet-based ones) are required. On the other hand, this study demonstrates that high energy lasers currently used for plasma X-ray sources can be conveniently and efficiently replaced by high average power and repetition rate laser radiation, as a way to increase the brightness of the generated X-rays.

  8. Color Developing Capacity of Plasma-treated Water as a Source of Nitrite for Meat Curing.

    Science.gov (United States)

    Jung, Samooel; Kim, Hyun Joo; Park, Sanghoo; Yong, Hae In; Choe, Jun Ho; Jeon, Hee-Joon; Choe, Wonho; Jo, Cheorun

    2015-01-01

    The interaction of plasma with liquid generates nitrogen species including nitrite (NO(-) 2). Therefore, the color developing capacity of plasma-treated water (PTW) as a nitrite source for meat curing was investigated in this study. PTW, which is generated by surface dielectric barrier discharge in air, and the increase of plasma treatment time resulted in increase of nitrite concentration in PTW. The PTW used in this study contains 46 ppm nitrite after plasma treatment for 30 min. To evaluate the effect of PTW on the cured meat color, meat batters were prepared under three different conditions (control, non-cured meat batter; PTW, meat batter cured with PTW; Sodium nitrite, meat batter cured with sodium nitrite). The meat batters were vacuum-packaged and cooked in a water-bath at 80℃ for 30 min. The typical color of cured meat developed in cooked meat batter treated with sodium nitrite or PTW. The lightness (L*) and yellowness (b*) values were similar in all conditions, whereas, the redness (a*) values of cooked meat batter with PTW and sodium nitrite (pnitrite source in the curing process of meat without addition of other nitrite sources.

  9. L-shell spectroscopic diagnostics of radiation from krypton HED plasma sources

    Energy Technology Data Exchange (ETDEWEB)

    Petkov, E. E., E-mail: emilp@unr.edu; Safronova, A. S.; Kantsyrev, V. L.; Shlyaptseva, V. V. [University of Nevada, Reno, Nevada 89557 (United States); Rawat, R. S.; Tan, K. S. [National Institute of Education, Nanyang Technological University, Singapore 637616 (Singapore); Beiersdorfer, P.; Brown, G. V. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Hell, N. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Dr. Remeis-Sternwarte and ECAP, Universität Erlangen-Nürnberg, 96049 Bamberg (Germany)

    2016-11-15

    X-ray spectroscopy is a useful tool for diagnosing plasma sources due to its non-invasive nature. One such source is the dense plasma focus (DPF). Recent interest has developed to demonstrate its potential application as a soft x-ray source. We present the first spectroscopic studies of krypton high energy density plasmas produced on a 3 kJ DPF device in Singapore. In order to diagnose spectral features, and to obtain a more comprehensive understanding of plasma parameters, a new non-local thermodynamic equilibrium L-shell kinetic model for krypton was developed. It has the capability of incorporating hot electrons, with different electron distribution functions, in order to examine the effects that they have on emission spectra. To further substantiate the validity of this model, it is also benchmarked with data gathered from experiments on the electron beam ion trap (EBIT) at Lawrence Livermore National Laboratory, where data were collected using the high resolution EBIT calorimeter spectrometer.

  10. L-shell spectroscopic diagnostics of radiation from krypton HED plasma sources.

    Science.gov (United States)

    Petkov, E E; Safronova, A S; Kantsyrev, V L; Shlyaptseva, V V; Rawat, R S; Tan, K S; Beiersdorfer, P; Hell, N; Brown, G V

    2016-11-01

    X-ray spectroscopy is a useful tool for diagnosing plasma sources due to its non-invasive nature. One such source is the dense plasma focus (DPF). Recent interest has developed to demonstrate its potential application as a soft x-ray source. We present the first spectroscopic studies of krypton high energy density plasmas produced on a 3 kJ DPF device in Singapore. In order to diagnose spectral features, and to obtain a more comprehensive understanding of plasma parameters, a new non-local thermodynamic equilibrium L-shell kinetic model for krypton was developed. It has the capability of incorporating hot electrons, with different electron distribution functions, in order to examine the effects that they have on emission spectra. To further substantiate the validity of this model, it is also benchmarked with data gathered from experiments on the electron beam ion trap (EBIT) at Lawrence Livermore National Laboratory, where data were collected using the high resolution EBIT calorimeter spectrometer.

  11. Liquid sampling-atmospheric pressure glow discharge as a secondary excitation source: Assessment of plasma characteristics

    Science.gov (United States)

    Manard, Benjamin T.; Gonzalez, Jhanis J.; Sarkar, Arnab; Dong, Meirong; Chirinos, Jose; Mao, Xianglei; Russo, Richard E.; Marcus, R. Kenneth

    The liquid sampling-atmospheric pressure glow discharge (LS-APGD) has been assessed as a secondary excitation source with a parametric evaluation regarding carrier gas flow rate, applied current, and electrode distance. With this parametric evaluation, plasma optical emission was monitored in order to obtain a fundamental understanding with regards to rotational temperature (Trot), excitation temperature (Texc), electron number density (ne), and plasma robustness. Incentive for these studies is not only for a greater overall fundamental knowledge of the APGD, but also in instrumenting a secondary excitation/ionization source following laser ablation (LA). Rotational temperatures were determined through experimentally fitting of the N2 and OH molecular emission bands while atomic excitation temperatures were calculated using a Boltzmann distribution of He and Mg atomic lines. The rotational and excitation temperatures were determined to be ~ 1000 K and ~ 2700 K respectively. Electron number density was calculated to be on the order of ~ 3 × 1015 cm- 3 utilizing Stark broadening effects of the Hα line of the Balmer series and a He I transition. In addition, those diagnostics were performed introducing magnesium (by solution feed and laser ablation) into the plasma in order to determine any perturbation under heavy matrix sampling. The so-called plasma robustness factor, derived by monitoring Mg II/Mg I emission ratios, is also employed as a reflection of potential perturbations in microplasma energetics across the various operation conditions and sample loadings. While truly a miniaturized source (laser ablation sample introduction.

  12. Positron Source from Betatron X-rays Emitted in a Plasma Wiggler

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, D.K.; Clayton, C.E.; Huang, C.; Joshi, C.; Lu, W.; Marsh, K.A.; Mori, W.B.; Zhou, M.; /UCLA; Barnes, C.D.; Decker, F.J.; Hogan, M.J.; Iverson, R.H.; Krejcik, P.; O' Connell, C.L.; Siemann, R.; Walz, D.R.; /SLAC; Deng, S.; Katsouleas, T.C.; Muggli, P.; Oz, E.; /Southern California U.

    2006-04-21

    In the E-167 plasma wakefield accelerator (PWFA) experiments in the Final Focus Test Beam (FFTB) at the Stanford Linear Accelerator Center (SLAC), an ultra-short, 28.5 GeV electron beam field ionizes a neutral column of Lithium vapor. In the underdense regime, all plasma electrons are expelled creating an ion column. The beam electrons undergo multiple betatron oscillations leading to a large flux of broadband synchrotron radiation. With a plasma density of 3 x 10{sup 17}cm{sup -3}, the effective focusing gradient is near 9 MT/m with critical photon energies exceeding 50 MeV for on-axis radiation. A positron source is the initial application being explored for these X-rays, as photo-production of positrons eliminates many of the thermal stress and shock wave issues associated with traditional Bremsstrahlung sources. Photo-production of positrons has been well-studied; however, the brightness of plasma X-ray sources provides certain advantages. In this paper, we present results of the simulated radiation spectra for the E-167 experiments, and compute the expected positron yield.

  13. Impedance of an intense plasma-cathode electron source for tokamak startup

    Science.gov (United States)

    Hinson, E. T.; Barr, J. L.; Bongard, M. W.; Burke, M. G.; Fonck, R. J.; Perry, J. M.

    2016-05-01

    An impedance model is formulated and tested for the ˜1 kV , 1 kA/cm2 , arc-plasma cathode electron source used for local helicity injection tokamak startup. A double layer sheath is established between the high-density arc plasma ( narc≈1021 m-3 ) within the electron source, and the less dense external tokamak edge plasma ( nedge≈1018 m-3 ) into which current is injected at the applied injector voltage, Vinj . Experiments on the Pegasus spherical tokamak show that the injected current, Iinj , increases with Vinj according to the standard double layer scaling Iinj˜Vinj3 /2 at low current and transitions to Iinj˜Vinj1 /2 at high currents. In this high current regime, sheath expansion and/or space charge neutralization impose limits on the beam density nb˜Iinj/Vinj1 /2 . For low tokamak edge density nedge and high Iinj , the inferred beam density nb is consistent with the requirement nb≤nedge imposed by space-charge neutralization of the beam in the tokamak edge plasma. At sufficient edge density, nb˜narc is observed, consistent with a limit to nb imposed by expansion of the double layer sheath. These results suggest that narc is a viable control actuator for the source impedance.

  14. Inductive plasma source for the ion treatment of AISI-304 SS

    International Nuclear Information System (INIS)

    Piedad-Beneitez, A de la; Lopez-Callejas, R; Granda-Gutierrez, E E; Rodriguez-Mendez, B G; Perez-Martinez, J A; Flores-Fuentes, A A; Valencia-Alvarado, R; Barocio, S R; Mercado-Cabrera, A; Pena-Eguiluz, R; Munoz-Castro, A E

    2008-01-01

    The design and construction of a simple inductive plasma source is described as constituted by an evacuated Pyrex glass cylinder reactor with 190 mm inner diameter and 500 mm length. This discharge vessel is coaxially surrounded by a cylindrically wound antenna, 240 mm in diameter, made of 3.2 mm wide copper wire. The antenna is supplied by a 13.56 MHz RF generator whose resulting electric field is able to create the plasma. When nitrogen is admitted to the vessel, the plasma generation takes place within the 0.1-50 Pa work pressure and 300-600 W RF power. The plasma density has been established by double Langmuir probes between 3.2 x 10 15 and 2.4 x 10 18 m -3 . This inductive plasma set up is meant to modify the surface of AISI-304 stainless steel by means of ion deposition, thanks to the sample bias provided by an external - 400 V dc supply, in order to improve the steel hardness without compromising its corrosion resistance. Once accelerated by the negative bias, the plasma ions impinge on the sample nitriding it by diffusion. The treated samples were characterized by x-ray diffraction (XRD) indicating the formation of the expanded gamma phase, by scanning electron microscopy (SEM) providing the atomic percentages of nitrogen, and by microhardness (HV) measurement.

  15. Modeling of the negative ions extraction from a hydrogen plasma source. Application to ITER Neutral Beam Injector

    International Nuclear Information System (INIS)

    Mochalskyy, S.

    2011-12-01

    The development of a high performance negative ion (NI) source constitutes a crucial step in the construction of a Neutral Beam Injector of the future fusion reactor ITER. NI source should deliver 40 A of H - or of D - . To address this problem in a realistic way, a 3D particles-in-cell electrostatic collisional code was developed. Binary collisions between the particles are introduced using Monte-Carlo collision scheme. This code called ONIX was used to investigate the plasma properties and the transport of the charged particles close to a typical extraction aperture. Results obtained from this code are presented in this thesis. They include negative ions and electrons 3D trajectories. The ion and electron current density profiles are shown for different local magnetic field configurations. Results of production, destruction, and transport of H - in the extraction region are also presented. The production of H - is investigated via 3 atomic processes: 1) electron dissociative attachment to the vibrationally excited molecules H 2 (v) in the volume, 2) interaction of the positive ions H + and H 2 + with the aperture wall and 3) collisions of the neutral gas H, H 2 with aperture wall. The influence of each process on the total extracted NI current is discussed. The extraction efficiency of H - from the volume is compared to the one of H - coming from the wall. Moreover, a parametric study of the H - surface production is presented. Results show the role of sheath behavior in the vicinity of the aperture developing a double layer structure responsible of the NI extraction limitations. The 2 following issues are also analysed. First the influence of the external extracted potential value on the formation of negative sheath and secondly the strength of the magnetic filter on the total extracted NI and co-extracted electron current. The suppression of the electron beam by the negative ion produced at the plasma grid wall is also discussed. Results are in good agreement

  16. High-resolution spectral analysis of light from neutral beams and ion source plasmas

    International Nuclear Information System (INIS)

    McNeill, D.H.; Kim, J.

    1980-05-01

    The spectral distributions of Balmer alpha emission from 7- and 22-cm-diam neutral hydrogen beams have been measured with a Fabry-Perot interferometer to obtain information on the beam energy, divergence, and species composition. Results of these measurements are compared with other data on the beam properties to evaluate high-resolution spectroscopy as a beam diagnostic technique. Measurements on ion source plasmas and on beam-produced background plasmas yield average neutral atom energies of approximately 0.3 and 2.5 eV, respectively

  17. Acceleration of relativistic electrons in plasma reactors and non-linear spectra of cosmic radio sources

    International Nuclear Information System (INIS)

    Kaplan, S.A.; Lomadze, R.D.

    1978-01-01

    A second approximation to the theory of turbulent plasma reactors in connection with the problem of interpretation of the non-linear spectra of cosmic radio sources has been investigated by the authors (Kaplan and Lomadze, 1977; Lomadze, 1977). The present paper discusses the basic results received for a Compton reactor with plasma waves of phase velocities smaller than the velocity of light, as well as for the synchrotron reactor. The distortion of the distribution function of relativistic electrons caused by their diffusion from the reactor is also presented as an example. (Auth.)

  18. Measurement of electron emission due to energetic ion bombardment in plasma source ion implantation

    Science.gov (United States)

    Shamim, M. M.; Scheuer, J. T.; Fetherston, R. P.; Conrad, J. R.

    1991-11-01

    An experimental procedure has been developed to measure electron emission due to energetic ion bombardment during plasma source ion implantation. Spherical targets of copper, stainless steel, graphite, titanium alloy, and aluminum alloy were biased negatively to 20, 30, and 40 kV in argon and nitrogen plasmas. A Langmuir probe was used to detect the propagating sheath edge and a Rogowski transformer was used to measure the current to the target. The measurements of electron emission coefficients compare well with those measured under similar conditions.

  19. From laser-plasma accelerators to femtosecond X-ray sources: study, development and applications

    International Nuclear Information System (INIS)

    Corde, S.

    2012-01-01

    During the relativistic interaction between a short and intense laser pulse and an underdense plasma, electrons can be injected and accelerated up to hundreds of MeV in an accelerating structure formed in the wake of the pulse: this is the so-called laser-plasma accelerator. One of the major perspectives for laser-plasma accelerators resides in the realization of compact sources of femtosecond x-ray beams. In this thesis, two x-ray sources was studied and developed. The betatron radiation, intrinsic to laser-plasma accelerators, comes from the transverse oscillations of electrons during their acceleration. Its characterization by photon counting revealed an x-ray beam containing 10"9 photons, with energies extending above 10 keV. We also developed an all-optical Compton source producing photons with energies up to hundreds of keV, based on the collision between a photon beam and an electron beam. The potential of these x-ray sources was highlighted by the realization of single shot phase contrast imaging of a biological sample. Then, we showed that the betatron x-ray radiation can be a powerful tool to study the physics of laser-plasma acceleration. We demonstrated the possibility to map the x-ray emission region, which gives a unique insight into the interaction, permitting us for example to locate the region where electrons are injected. The x-ray angular and spectral properties allow us to gain information on the transverse dynamics of electrons during their acceleration. (author)

  20. Study of Au- production in a plasma-sputter type negative ion source

    International Nuclear Information System (INIS)

    Okabe, Yushirou.

    1991-10-01

    A negative ion source of plasma-sputter type has been constructed for the purpose of studying physical processes which take place in the ion source. Negative ions of gold are produced on the gold target which is immersed in an argon discharge plasma and biased negatively with respect to the plasma. The work function of the target surface was lowered by the deposition of Cs on the target. An in-situ method has been developed to determine the work function of the target surface in the ion source under discharge conditions. The observed minimum work function of a cesiated gold surface in an argon plasma was 1.3 eV, when the negative ion production rate took the maximum value. The production rate increased monotonically and saturated when the surface work function was reduced from 1.9 eV to 1.3 eV. The dependence of Au - production rate on the incident ion energy and on the number of the incident ion was studied. From the experimental results, it is shown that the sputtering process is an important physical process for the negative ion production in the plasma-sputter type negative ion source. The energy distribution function was also measured. When the bias voltage was smaller than 280 V, the high energy component in the distribution decreased as the target voltage was decreased. Therefore, the energy spread ΔE, of the observed negative ion energy distribution also decreased. This tendency is also seen in the energy spectrum of Cu atoms sputtered in normal direction by Ar + ions. (J.P.N.)