National Library of Energy BETA

Sample records for density plasma science

  1. High Energy Density Laboratory Plasmas

    E-Print Network [OSTI]

    High Energy Density Laboratory Plasmas General Plasma Science Developing founda/ons and advancing fundamental understanding #12;The High Energy Density developing innovative techniques to study the properties of instabilities in magnetized-high-energy-density

  2. 844 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 34, NO. 3, JUNE 2006 Energy Balance and Plasma Potential in Low-Density

    E-Print Network [OSTI]

    Kaganovich, Igor

    ARECENT model for particle balance and energy balance in low-density, hot-filament discharges [1] gives844 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 34, NO. 3, JUNE 2006 Energy Balance and Plasma Potential in Low-Density Hot-Filament Discharges Scott Robertson, Senior Member, IEEE, Scott Knappmiller

  3. 2810 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 39, NO. 11, NOVEMBER 2011 The Effect of Critical Plasma Densities of

    E-Print Network [OSTI]

    Harilal, S. S.

    in hydro- dynamic evolution of the produced plasma sources. Index Terms--CO2 laser, critical density and optimization of radiation sources for the next generation of nanolithography, i.e., the extreme ultravi- olet

  4. Measurements of plasma bremsstrahlung and plasma energy density produced by electron cyclotron resonance ion source plasmas

    E-Print Network [OSTI]

    Noland, Jonathan David

    2011-01-01

    of x-ray power and plasma energy density with microwaveof diamagnetic loop used for plasma energy density mea-the average electron energy and density. During the slowly

  5. SciTech Connect: "plasma science"

    Office of Scientific and Technical Information (OSTI)

    plasma science" Find + Advanced Search Term Search Semantic Search Advanced Search All Fields: "plasma science" Semantic Semantic Term Title: Full Text: Bibliographic Data:...

  6. High Energy Density Laboratory Plasmas Program | National Nuclear...

    National Nuclear Security Administration (NNSA)

    Photo Gallery Jobs Apply for Our Jobs Our Jobs Working at NNSA Blog Home High Energy Density Laboratory Plasmas Program High Energy Density Laboratory Plasmas Program...

  7. Using Radio Waves to Control Fusion Plasma Density

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

    Using Radio Waves to Control Fusion Plasma Density Using Radio Waves to Control Fusion Plasma Density Simulations Run at NERSC Support Fusion Experiments at MIT, General Atomics...

  8. Boundary Plasma Issues in Burning Plasma Science

    E-Print Network [OSTI]

    Pitcher, C. S.

    impurity production 4. screening of impurities · why a burning plasma experiment? · BP contribution impurity production, high Zeff (not desirable mode of operation ) #12;···· we know a lot more now than helium ash - induce SOL flow towards divertor - control density · helium exhaust time, i.e. He , limited

  9. High energy density Z-pinch plasmas using flow stabilization

    SciTech Connect (OSTI)

    Shumlak, U. Golingo, R. P. Nelson, B. A. Bowers, C. A. Doty, S. A. Forbes, E. G. Hughes, M. C. Kim, B. Knecht, S. D. Lambert, K. K. Lowrie, W. Ross, M. P. Weed, J. R.

    2014-12-15

    The ZaP Flow Z-Pinch research project[1] at the University of Washington investigates the effect of sheared flows on MHD instabilities. Axially flowing Z-pinch plasmas are produced that are 100 cm long with a 1 cm radius. The plasma remains quiescent for many radial Alfvén times and axial flow times. The quiescent periods are characterized by low magnetic mode activity measured at several locations along the plasma column and by stationary visible plasma emission. Plasma evolution is modeled with high-resolution simulation codes – Mach2, WARPX, NIMROD, and HiFi. Plasma flow profiles are experimentally measured with a multi-chord ion Doppler spectrometer. A sheared flow profile is observed to be coincident with the quiescent period, and is consistent with classical plasma viscosity. Equilibrium is determined by diagnostic measurements: interferometry for density; spectroscopy for ion temperature, plasma flow, and density[2]; Thomson scattering for electron temperature; Zeeman splitting for internal magnetic field measurements[3]; and fast framing photography for global structure. Wall stabilization has been investigated computationally and experimentally by removing 70% of the surrounding conducting wall to demonstrate no change in stability behavior.[4] Experimental evidence suggests that the plasma lifetime is only limited by plasma supply and current waveform. The flow Z-pinch concept provides an approach to achieve high energy density plasmas,[5] which are large, easy to diagnose, and persist for extended durations. A new experiment, ZaP-HD, has been built to investigate this approach by separating the flow Z-pinch formation from the radial compression using a triaxial-electrode configuration. This innovation allows more detailed investigations of the sheared flow stabilizing effect, and it allows compression to much higher densities than previously achieved on ZaP by reducing the linear density and increasing the pinch current. Experimental results and scaling analyses will be presented. In addition to studying fundamental plasma science and high energy density physics, the ZaP and ZaP-HD experiments can be applied to laboratory astrophysics.

  10. Extreme hydrogen plasma densities achieved in a linear plasma generator

    SciTech Connect (OSTI)

    Rooij, G. J. van; Veremiyenko, V. P.; Goedheer, W. J.; de Groot, B.; Kleyn, A. W.; Smeets, P. H. M.; Versloot, T. W.; Whyte, D. G.; Engeln, R.; Schram, D. C.; Cardozo, N. J. Lopes

    2007-03-19

    A magnetized hydrogen plasma beam was generated with a cascaded arc, expanding in a vacuum vessel at an axial magnetic field of up to 1.6 T. Its characteristics were measured at a distance of 4 cm from the nozzle: up to a 2 cm beam diameter, 7.5x10{sup 20} m{sup -3} electron density, {approx}2 eV electron and ion temperatures, and 3.5 km/s axial plasma velocity. This gives a 2.6x10{sup 24} H{sup +} m{sup -2} s{sup -1} peak ion flux density, which is unprecedented in linear plasma generators. The high efficiency of the source is obtained by the combined action of the magnetic field and an optimized nozzle geometry. This is interpreted as a cross-field return current that leads to power dissipation in the beam just outside the source.

  11. NSTX Diagnostics for Fusion Plasma Science Studies

    SciTech Connect (OSTI)

    R. Kaita; D. Johnson; L. Roquemore; M. Bitter; F. Levinton; F. Paoletti; D. Stutman; and the NSTX Team

    2001-07-05

    This paper will discuss how plasma science issues are addressed by the diagnostics for the National Spherical Torus Experiment (NSTX), the newest large-scale machine in the magnetic confinement fusion (MCF) program. The development of new schemes for plasma confinement involves the interplay of experimental results and theoretical interpretations. A fundamental requirement, for example, is a determination of the equilibria for these configurations. For MCF, this is well established in the solutions of the Grad-Shafranov equation. While it is simple to state its basis in the balance between the kinetic and magnetic pressures, what they are as functions of space and time are often not easy to obtain. Quantities like the plasma pressure and current density are not directly measurable. They are derived from data that are themselves complex products of more basic parameters. The same difficulties apply to the understanding of plasma instabilities. Not only are the needs for spatial and temporal resolution more stringent, but the wave parameters which characterize the instabilities are difficult to resolve. We will show how solutions to the problems of diagnostic design on NSTX, and the physics insight the data analysis provides, benefits both NSTX and the broader scientific community.

  12. Magnetic confinement of a high-density cylindrical plasma

    SciTech Connect (OSTI)

    Ahedo, Eduardo [E. T. S. Ingenieros Aeronauticos, Universidad Politecnica de Madrid, Madrid 28040 (Spain)

    2011-10-15

    The stationary structure of a weakly collisional plasma column, confined by an axial magnetic field and a cylindrical vessel, is studied for the high-density case, when the diamagnetic azimuthal current is large enough to demagnetize partially the plasma. The plasma response is characterized mainly by two dimensionless parameters: the ratios of the electron gyroradius and the electron skin-depth to the plasma radius, and each of them measures the independent influence of the applied magnetic field and the plasma density on the plasma response. The strong magnetic confinement regime, characterized by very small wall losses, is limited to the small gyroradius and large skin-depth ranges. In the high-density case, when the electron skin-depth is smaller than the electron gyroradius, the skin-depth turns out to be the magnetic screening length, so that the bulk of the plasma behaves as unmagnetized.

  13. Operational plasma density and laser parameters for future colliders based on laser-plasma accelerators

    SciTech Connect (OSTI)

    Schroeder, C. B.; Esarey, E.; Leemans, W. P.

    2012-12-21

    The operational plasma density and laser parameters for future colliders based on laser-plasma accelerators are discussed. Beamstrahlung limits the charge per bunch at low plasma densities. Reduced laser intensity is examined to improve accelerator efficiency in the beamstrahlung-limited regime.

  14. CENTER FOR PULSED POWER DRIVEN HIGH ENERGY DENSITY PLASMA STUDIES

    SciTech Connect (OSTI)

    Professor Bruce R. Kusse; Professor David A. Hammer

    2007-04-18

    This annual report summarizes the activities of the Cornell Center for Pulsed-Power-Driven High-Energy-Density Plasma Studies, for the 12-month period October 1, 2005-September 30, 2006. This period corresponds to the first year of the two-year extension (awarded in October, 2005) to the original 3-year NNSA/DOE Cooperative Agreement with Cornell, DE-FC03-02NA00057. As such, the period covered in this report also corresponds to the fourth year of the (now) 5-year term of the Cooperative Agreement. The participants, in addition to Cornell University, include Imperial College, London (IC), the University of Nevada, Reno (UNR), the University of Rochester (UR), the Weizmann Institute of Science (WSI), and the P.N. Lebedev Physical Institute (LPI), Moscow. A listing of all faculty, technical staff and students, both graduate and undergraduate, who participated in Center research activities during the year in question is given in Appendix A.

  15. Boundary Plasma Issues in Burning Plasma Science

    E-Print Network [OSTI]

    impurity production 4. screening of impurities 5. burning plasma experiment? #12;(1) Wide Dispersal points are swept (BPX), but Tt will be high impurity production, high Zeff (not desirable mode- modes (tight baffling??) · allows efficient pumping to: - remove helium ash - induce SOL flow towards

  16. Boundary Plasma Issues in Burning Plasma Science

    E-Print Network [OSTI]

    Pitcher, C. S.

    impurity production 4. screening of impurities 5. burning plasma experiment? #12;(1) Wide Dispersal if strike points are swept (BPX), but Tt will be high impurity production, high Zeff (not desirable mode pressure for H- modes (tight baffling??) · allows efficient pumping to: - remove helium ash - induce SOL

  17. Relativistic plasma nanophotonics for ultrahigh energy density physics

    E-Print Network [OSTI]

    Rocca, Jorge J.

    Relativistic plasma nanophotonics for ultrahigh energy density physics Michael A. Purvis1 of the laser energy into a thin surface layer at typically only 0.1% of solid density. Here, we demonstrate density Nec using multi-kilojoule laser pulses1­4 . Such high- energy laser pulses have ionized mid

  18. Basic Plasma Science | Princeton Plasma Physics Lab

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory of raregovAboutRecovery ActTools toBadging, Badge Office Badging,Basic Plasma

  19. Plasma actuator electron density measurement using microwave perturbation method

    SciTech Connect (OSTI)

    Mirhosseini, Farid; Colpitts, Bruce [Electrical and Computer Engineering, University of New Brunswick, Fredericton, New Brunswick E3B 5A3 (Canada)

    2014-07-21

    A cylindrical dielectric barrier discharge plasma under five different pressures is generated in an evacuated glass tube. This plasma volume is located at the center of a rectangular copper waveguide cavity, where the electric field is maximum for the first mode and the magnetic field is very close to zero. The microwave perturbation method is used to measure electron density and plasma frequency for these five pressures. Simulations by a commercial microwave simulator are comparable to the experimental results.

  20. Relation between plasma plume density and gas flow velocity in atmospheric pressure plasma

    SciTech Connect (OSTI)

    Yambe, Kiyoyuki; Taka, Shogo; Ogura, Kazuo [Graduate School of Science and Technology, Niigata University, Niigata 950-2181 (Japan)] [Graduate School of Science and Technology, Niigata University, Niigata 950-2181 (Japan)

    2014-04-15

    We have studied atmospheric pressure plasma generated using a quartz tube, helium gas, and copper foil electrode by applying RF high voltage. The atmospheric pressure plasma in the form of a bullet is released as a plume into the atmosphere. To study the properties of the plasma plume, the plasma plume current is estimated from the difference in currents on the circuit, and the drift velocity is measured using a photodetector. The relation of the plasma plume density n{sub plu}, which is estimated from the current and the drift velocity, and the gas flow velocity v{sub gas} is examined. It is found that the dependence of the density on the gas flow velocity has relations of n{sub plu} ? log(v{sub gas}). However, the plasma plume density in the laminar flow is higher than that in the turbulent flow. Consequently, in the laminar flow, the density increases with increasing the gas flow velocity.

  1. EnergyandPower Plasma Science

    E-Print Network [OSTI]

    Cafarella, Michael J.

    and Computer Vision 9 Energy and Power Systems 10 Quantum Science and Devices 11 Signal and Image Processing 12 Science andDevices ControlSystems SignalandImage Processing Communications Opticsand Photonics RoboticsVLSI Quantum Science andDevices ControlSystems Security Inform ation TechnologyTransportation S pace Energy

  2. Stable laser–plasma accelerators at low densities

    SciTech Connect (OSTI)

    Li, Song; Hafz, Nasr A. M. Mirzaie, Mohammad; Ge, Xulei; Sokollik, Thomas; Chen, Min; Sheng, Zhengming; Zhang, Jie

    2014-07-28

    We report stable laser wakefield acceleration using 17–50 TW laser pulses interacting with 4?mm-long helium gas jet. The initial laser spot size was relatively large (28??m) and the plasma densities were 0.48–2.0?×?10{sup 19?}cm{sup ?3}. High-quality 100–MeV electron beams were generated at the plasma density of 7.5?×?10{sup 18?}cm{sup ?3}, at which the beam parameters (pointing angle, energy spectrum, charge, and divergence angle) were measured and stabilized. At higher densities, filamentation instability of the laser-plasma interaction was observed and it has led to multiple wakefield accelerated electron beams. The experimental results are supported by 2D particle-in-cell simulations. The achievement presented here is an important step toward the use of laser-driven accelerators in real applications.

  3. Observation of low magnetic field density peaks in helicon plasma

    SciTech Connect (OSTI)

    Barada, Kshitish K.; Chattopadhyay, P. K.; Ghosh, J.; Kumar, Sunil; Saxena, Y. C. [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)

    2013-04-15

    Single density peak has been commonly observed in low magnetic field (<100 G) helicon discharges. In this paper, we report the observations of multiple density peaks in low magnetic field (<100 G) helicon discharges produced in the linear helicon plasma device [Barada et al., Rev. Sci. Instrum. 83, 063501 (2012)]. Experiments are carried out using argon gas with m = +1 right helical antenna operating at 13.56 MHz by varying the magnetic field from 0 G to 100 G. The plasma density varies with varying the magnetic field at constant input power and gas pressure and reaches to its peak value at a magnetic field value of {approx}25 G. Another peak of smaller magnitude in density has been observed near 50 G. Measurement of amplitude and phase of the axial component of the wave using magnetic probes for two magnetic field values corresponding to the observed density peaks indicated the existence of radial modes. Measured parallel wave number together with the estimated perpendicular wave number suggests oblique mode propagation of helicon waves along the resonance cone boundary for these magnetic field values. Further, the observations of larger floating potential fluctuations measured with Langmuir probes at those magnetic field values indicate that near resonance cone boundary; these electrostatic fluctuations take energy from helicon wave and dump power to the plasma causing density peaks.

  4. MIT Plasma Science & Fusion Center: research>alcator>introduction

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

    Technology & Engineering Plasma Technology Waves & Beams Useful Links Diagnostic Needs (Updated as of June 2010) Profiles Electron density profiles: We desire a density profile...

  5. Plasma ionization frequency, edge-to-axis density ratio, and density on axis of a cylindrical gas discharge

    SciTech Connect (OSTI)

    Palacio Mizrahi, J. H.

    2014-06-15

    A rigorous derivation of expressions, starting from the governing equations, for the ionization frequency, edge-to-axis ratio of plasma density, plasma density at the axis, and radially averaged plasma density in a cylindrical gas discharge has been obtained. The derived expressions are simple and involve the relevant parameters of the discharge: Cylinder radius, axial current, and neutral gas pressure. The found expressions account for ion inertia, ion temperature, and changes in plasma ion collisionality.

  6. On the density limit in the helicon plasma sources

    SciTech Connect (OSTI)

    Kotelnikov, Igor A.

    2014-12-15

    Existence of the density limit in the helicon plasma sources is revisited. The low- and high-frequency regimes of a helicon plasma source operation are distinguished. In the low-frequency regime with ?density limit is deduced from the Golant-Stix criterion of the accessibility of the lower hybrid resonance. In the high-frequency case, ?>?(?{sub ci}?{sub ce}), an appropriate limit is given by the Shamrai-Taranov criterion. Both these criteria are closely related to the phenomenon of the coalescence of the helicon wave with the Trivelpiece-Gould mode. We draw a conclusion that the derived density limits are not currently achieved in existing devices, perhaps, because of high energy cost of gas ionization.

  7. Helicon Plasma Source Configuration Analysis by Means of Density Measurements

    SciTech Connect (OSTI)

    Angrilli, F.; Barber, G.C.; Carter, M.D.; Goulding, R.H.; Maggiora, R.; Pavarin, D.; Sparks, D.O.

    1999-11-13

    Initial results have been obtained from operation of a helicon plasma source built to conduct optimization studies for space propulsion applications. The source features an easily reconfigurable antenna to test different geometries. Operating with He as the source gas, peak densities >= 1.6X10{sup 19} m{sup -3} have been achieved. Radial and axial plasma profiles have been obtained using a microwave interferometer that can be scanned axially and a Langmuir probe. The source will be used to investigate operation at high magnetic field, frequency, and input power.

  8. Magnetohydrodynamically stable plasma with supercritical current density at the axis

    SciTech Connect (OSTI)

    Burdakov, A. V. [Budker Institute of Nuclear Physics, 11 Lavrentjev Avenue, 630090 Novosibirsk (Russian Federation); Novosibirsk State Technical University, 20 Karl Marks Avenue, 630092 Novosibirsk (Russian Federation); Postupaev, V. V., E-mail: V.V.Postupaev@inp.nsk.su; Sudnikov, A. V. [Budker Institute of Nuclear Physics, 11 Lavrentjev Avenue, 630090 Novosibirsk (Russian Federation); Novosibirsk State University, 2 Pirogova st., 630090 Novosibirsk (Russian Federation)

    2014-05-15

    In this work, an analysis of magnetic perturbations in the GOL-3 experiment is given. In GOL-3, plasma is collectively heated in a multiple-mirror trap by a high-power electron beam. During the beam injection, the beam-plasma interaction maintains a high-level microturbulence. This provides an unusual radial profile of the net current (that consists of the beam current, current of the preliminary discharge, and the return current). The plasma core carries supercritical current density with the safety factor well below unity, but as a whole, the plasma is stable with q(a)???4. The net plasma current is counter-directed to the beam current; helicities of the magnetic field in the core and at the edge are of different signs. This forms a system with a strong magnetic shear that stabilizes the plasma core in good confinement regimes. We have found that the most pronounced magnetic perturbation is the well-known n?=?1, m?=?1 mode for both stable and disruptive regimes.

  9. Research Opportunities in High Energy Density Laboratory Plasmas on the NDCX-II Facility

    E-Print Network [OSTI]

    Barnard, John

    2009-01-01

    of Science, Office of Fusion Energy Sciences, of the U.S.density physics and inertial fusion energy science. Thesedrivers for inertial fusion energy applications. Experiments

  10. Magnetic confinement of a high-density cylindrical plasma Eduardo Ahedoa)

    E-Print Network [OSTI]

    Carlos III de Madrid, Universidad

    collisional plasma column, confined by an axial magnetic field and a cylindrical vessel, is studiedMagnetic confinement of a high-density cylindrical plasma Eduardo Ahedoa) E. T. S. Ingenieros the independent influence of the applied magnetic field and the plasma density on the plasma response. The strong

  11. The expansion of a collisionless plasma into a plasma of lower density

    SciTech Connect (OSTI)

    Perego, M.; Gunzburger, M. D.; Howell, P. D.; Ockendon, J. R.; Allen, J. E.

    2013-05-15

    This paper considers the asymptotic and numerical solution of a simple model for the expansion of a collisionless plasma into a plasma of lower density. The dependence on the density ratio of qualitative and quantitative features of solutions of the well-known cold-ion model is explored. In the cold-ion limit, we find that a singularity develops in the ion density in finite time unless the density ratio is zero or close to unity. The classical cold-ion model may cease to be valid when such a singularity occurs and we then regularize the model by the finite ion-temperature Vlasov-Poisson system. Numerical evidence suggests the emergence of a multi-modal velocity distribution.

  12. Radio Scintillation due to Discontinuities in the Interstellar Plasma Density

    E-Print Network [OSTI]

    Hendrik Lambert; Barney Rickett

    1999-11-18

    We develop the theory of interstellar scintillation as caused by an irregular plasma having a power-law spatial density spectrum with a spectral exponent of 4 corresponding to a medium with abrupt changes in its density. An ``outer scale'' is included in the model representing the typical scale over which the density of the medium remains uniform. Such a spectrum could be used to model plasma shock fronts in supernova remnants or other plasma discontinuities. We investigate and develop equations for the decorrelation bandwidth of diffractive scintillations and the refractive scintillation index and compare our results with pulsar measurements. We consider both a medium concentrated in a thin layer and an extended irregular medium. We conclude that the discontinuity model gives satisfactory agreement for many diffractive measurements, in particular the VLBI meaurements of the structure function exponent between 5/3 and 2. However, it gives less satisfactory agreement for the refractive scintillation index than does the Kolmogorov turbulence spectrum. The comparison suggests that the medium consists of a pervasive background distribution of turbulence embedded with randomly placed discrete plasma structures such as shocks or HII regions. This can be modeled by a composite spectrum following the Kolmogorov form at high wavenumbers and steepening at lower wavenumbers corresponding to the typical (inverse) size of the discrete structures. Such a model can also explain the extreme scattering events. However, lines of sight through the enhanced scattering prevalent at low galactic latitudes are accurately described by the Kolmogorov spectrum in an extended medium and do not appear to have a similar low-wavenumber steepening.

  13. MIT Plasma Science & Fusion Center: research>alcator>information

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

    Administration Computers & Networks Calendar Safety Search PSFC Go Plasma Science and Fusion Center Massachusetts Institute of Technology About PSFC Research People Education News...

  14. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL.

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverse (JournalvivoHighHussein KhalilResearch8 IEEE TRANSACTIONS ON PLASMA SCIENCE,

  15. MIT Plasma Science & Fusion Center: research>alcator>research...

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

    Contact Information Physics Research High-Energy- Density Physics Waves & Beams Fusion Technology & Engineering Plasma Technology Useful Links Collaborations at Alcator...

  16. Measurements of plasma bremsstrahlung and plasma energy density produced by electron cyclotron resonance ion source plasmas

    E-Print Network [OSTI]

    Noland, Jonathan David

    2011-01-01

    confinement was achieved with a magnetic mirror field. Twoplasma confinement[16]. The strength of the magnetic fieldfield A simple plasma confinement scheme, used in early fusion devices, is the “magnetic

  17. MIT Plasma Science and Fusion Center Fusion Technology & Engineering Division

    E-Print Network [OSTI]

    Fusion Technology & Engineering Division 1. Costing of 4 "Reference" Options 2. Equalization of TF;MIT Plasma Science and Fusion Center Fusion Technology & Engineering Division Total Cost (M$) vs. A; MMIT Plasma Science and Fusion Center Fusion Technology & Engineering Division J.H. Schultz M

  18. Modeling of free electronic state density in hydrogenic plasmas based on nearest neighbor approximation

    SciTech Connect (OSTI)

    Nishikawa, Takeshi

    2014-07-15

    Most conventional atomic models in a plasma do not treat the effect of the plasma on the free-electron state density. Using a nearest neighbor approximation, the state densities in hydrogenic plasmas for both bound and free electrons were evaluated and the effect of the plasma on the atomic model (especially for the state density of the free electron) was studied. The model evaluates the electron-state densities using the potential distribution formed by the superposition of the Coulomb potentials of two ions. The potential from one ion perturbs the electronic state density on the other. Using this new model, one can evaluate the free-state density without making any ad-hoc assumptions. The resulting contours of the average ionization degree, given as a function of the plasma temperature and density, are shifted slightly to lower temperatures because of the effect of the increasing free-state density.

  19. PLASMA FOCUSING OF HIGH ENERGY DENSITY ELECTRON AND POSITRON BEAMS \\Lambda

    E-Print Network [OSTI]

    PLASMA FOCUSING OF HIGH ENERGY DENSITY ELECTRON AND POSITRON BEAMS \\Lambda J.S.T. Ng, P. Chen, W present results from the SLAC E­150 experiment on plasma focusing of high energy density electron and experiments to test this con­ cept were carried out with low energy density electron beams [2]. The goals

  20. Pressure-driven, resistive magnetohydrodynamic interchange instabilities in laser-produced high-energy-density plasmas

    E-Print Network [OSTI]

    Li, Chikang

    Recent experiments using proton backlighting of laser-foil interactions provide unique opportunities for studying magnetized plasma instabilities in laser-produced high-energy-density plasmas. Time-gated proton radiograph ...

  1. Exploration of Plasma Jets Approach to High Energy Density Physics. Final report

    SciTech Connect (OSTI)

    Chen, Chiping

    2013-08-26

    High-energy-density laboratory plasma (HEDLP) physics is an emerging, important area of research in plasma physics, nuclear physics, astrophysics, and particle acceleration. While the HEDLP regime occurs at extreme conditions which are often found naturally in space but not on the earth, it may be accessible by colliding high intensity plasmas such as high-energy-density plasma jets, plasmoids or compact toroids from plasma guns. The physics of plasma jets is investigated in the context of high energy density laboratory plasma research. This report summarizes results of theoretical and computational investigation of a plasma jet undergoing adiabatic compression and adiabatic expansion. A root-mean-squared (rms) envelope theory of plasma jets is developed. Comparison between theory and experiment is made. Good agreement between theory and experiment is found.

  2. Effect of density changes on tokamak plasma confinement

    E-Print Network [OSTI]

    Spineanu, F

    2015-01-01

    A change of the particle density (by gas puff, pellets or impurity seeding) during the plasma discharge in tokamak produces a radial current and implicitly a torque and rotation that can modify the state of confinement. After ionization the newly born ions will evolve toward the periodic neoclassical orbits (trapped or circulating) but the first part of their excursion, which precedes the periodicity, is an effective radial current. It is short, spatially finite and unique for each new ion, but multiplied by the rate of ionization and it can produce a substantial total radial current. The associated torque induces rotation which modify the transport processes. We derive the magnitude of the radial current induced by ionization by three methods: the analysis of a simple physical picture, a numerical model and the neoclassical drift-kinetic treatment. The results of the three approaches are in agreement and show that the current can indeed be substantial. Many well known experimental observations can be reconsi...

  3. Fine density/design variable Computational Science and Engineering

    E-Print Network [OSTI]

    Paulino, Glaucio H.

    1400 1600 FE Analysis Optimization Initialization Buildings designed to minimize seismic or wind·Fine density/design variable mesh Computational Science and Engineering 2013 Annual Meeting.01 Fine design variable mesh Fine density variable mesh Comparison of forced vibration results 1

  4. HIGHLY COMPRESSED ION BEAMS FOR HIGH ENERGY DENSITY SCIENCE

    E-Print Network [OSTI]

    Wurtele, Jonathan

    HIGHLY COMPRESSED ION BEAMS FOR HIGH ENERGY DENSITY SCIENCE A. Friedman1,2 , J.J.Barnard1,2 , R Energy Density regimes required for Inertial Fu- sion Energy and other applications. An interim goal we are pursuing, low to medium mass ions with energies just above the Bragg peak are directed onto

  5. 2012 APS-DPP Plasma Science Expo, Providence, RI | Princeton...

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

    APS-DPP Plasma Science Expo, Providence, RI View larger image IMG 1847 View larger image IMG 1598 View larger image IMG 1608 View larger image IMG 1609 View larger image IMG 1614...

  6. Assessment of plasma impedance probe for measuring electron density and collision frequency in a plasma with spatial and temporal gradients

    SciTech Connect (OSTI)

    Hopkins, Mark A. King, Lyon B.

    2014-05-15

    Numerical simulations and experimental measurements were combined to determine the ability of a plasma impedance probe (PIP) to measure plasma density and electron collision frequency in a plasma containing spatial gradients as well as time-varying oscillations in the plasma density. A PIP is sensitive to collision frequency through the width of the parallel resonance in the Re[Z]-vs.-frequency characteristic, while also being sensitive to electron density through the zero-crossing of the Im[Z]-vs.-frequency characteristic at parallel resonance. Simulations of the probe characteristic in a linear plasma gradient indicated that the broadening of Re[Z] due to the spatial gradient obscured the broadening due to electron collision frequency, preventing a quantitative measurement of the absolute collision frequency for gradients considered in this study. Simulation results also showed that the PIP is sensitive to relative changes in electron collision frequency in a spatial density gradient, but a second broadening effect due to time-varying oscillations made collision frequency measurements impossible. The time-varying oscillations had the effect of causing multiple zero-crossings in Im[Z] at parallel resonance. Results of experiments and simulations indicated that the lowest-frequency zero-crossing represented the lowest plasma density in the oscillations and the highest-frequency zero-crossing represented the highest plasma density in the oscillations, thus the PIP probe was found to be an effective tool to measure both the average plasma density as well as the maximum and minimum densities due to temporal oscillations.

  7. Presented at UFA Burning Plasma Science Workshop II

    E-Print Network [OSTI]

    for a Next Step Experiment in Magnetic Fusion · Compact High Field Approach - General Parameters · Burning for Resolving the Critical Fusion Plasma Science Issues for an Attractive MFE Reactor Burning Plasma Experiment 1, 2001 FIRE Lighting the Way to Fusion A Next Step Option for Magnetic Fusion for the FIRE Team

  8. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 31, NO. 4, AUGUST 2003 691 Plasma Molding Over Surface Topography

    E-Print Network [OSTI]

    Economou, Demetre J.

    IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 31, NO. 4, AUGUST 2003 691 Plasma Molding Over Surface) simulation model was developed to study plasma "molding" over a trench. The radio frequency sheath potential (MC) simulation, plasma molding, two-dimensional (2-D) plasma sheath. I. INTRODUCTION ASHEATH forms

  9. Internal field, density & temperature measurements in MTF plasmas...

    Office of Scientific and Technical Information (OSTI)

    temperature measurements in MTF plasmas using Pulsed Polarimetry final report Authors: Smith, Roger J. Publication Date: 2014-08-11 OSTI Identifier: 1149491 Report Number(s): 001...

  10. Density modification by two superposing TE{sub 10} modes in a plasma filled rectangular waveguide

    SciTech Connect (OSTI)

    Tomar, Sanjay K.; Malik, Hitendra K. [Plasma Waves and Particle Acceleration Laboratory, Department of Physics, Indian Institute of Technology Delhi, New Delhi 110 016 (India)] [Plasma Waves and Particle Acceleration Laboratory, Department of Physics, Indian Institute of Technology Delhi, New Delhi 110 016 (India)

    2013-07-15

    Microwave and plasma interaction is examined via two fundamental TE{sub 10} modes propagating in a plasma filled rectangular waveguide after superposing at a smaller angle. The propagation of the resultant mode realized from these two modes is governed by a wave equation obtained using the Maxwell's equations. This equation is solved numerically using fourth order Runge-Kutta method for the field amplitude of the microwave in the waveguide considering the waveguide to be made up of a perfect conductor and filled with different types of initial plasma density distributions, viz. homogeneous density, linear density with gradient in the propagation direction, and the density with Gaussian profile along the waveguide width. A phenomenon similar to the duct formation by high power microwaves is found to take place, where the plasma density attains interesting profiles. These profiles can be controlled by the angle of superposition, phase difference between the fields of the two modes, microwave frequency and microwave field amplitude.

  11. Stark broadening of high principal quantum number hydrogen Balmer lines in low-density laboratory plasmas

    E-Print Network [OSTI]

    Stark broadening of high principal quantum number hydrogen Balmer lines in low-density laboratory an electron density di- agnostic, e.g., for tokamak edge plasmas 1­3 and other magnetic fusion energy MFE show a very good agreement. Density and temperature dependences of the linewidths, as well as relative

  12. MIT Research using High-Energy Density Plasmas at OMEGA and the NIF

    E-Print Network [OSTI]

    MIT Research using High-Energy Density Plasmas at OMEGA and the NIF Hans Rinderknecht Wednesday He D-D T 2.3 m SiO2 D3He gas 860 m #12;The High Energy Density Physics Division at MIT of Inertial Confinement Fusion (ICF) implosions VII. Proton Radiography #12;High Energy Density Physics

  13. Inertial Confinement Fusion, High Energy Density Plasmas and an Energy Source on Earth

    E-Print Network [OSTI]

    Inertial Confinement Fusion, High Energy Density Plasmas and an Energy Source on Earth Max Tabak ignition robust burn Supernova core MFE ICF ignition requires large energy and power densities Log10 Achieving the necessary multiplication of power,energy and mass densities requires a well controlled

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

    SciTech Connect (OSTI)

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

    2014-03-15

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

  15. Plasma Facing Component Science and Technology for Burning Plasma Experiments

    E-Print Network [OSTI]

    operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under HeatFlux(MW/m2 ) Disruptions Reentry Vehicles Fusion Divertor Fusion First Wall Fast Breeder Fission Reactor Radiant Flux at Sun Surface Rocket Nozzles Comparison Relative Heat Fluxes Fusion Plasma #12;MAU

  16. Poloidal Density Variation of Impurities in a Rotating Tokamak Plasma ­ Flux Surface Coordinates and Effect on Transport Coefficients

    E-Print Network [OSTI]

    Poloidal Density Variation of Impurities in a Rotating Tokamak Plasma ­ Flux Surface Coordinates and Effect on Transport Coefficients

  17. Tunable Laser Plasma Accelerator based on Longitudinal Density Tailoring

    E-Print Network [OSTI]

    Gonsalves, Anthony

    2012-01-01

    38 fs. Laser and electron beam diagnostics Laser radiationdiagnostic provided charge density images of the electron beam

  18. Plasma density from Cerenkov radiation, betatron oscillations, and beam steering in a plasma wakefield experiment at 30 GeV

    SciTech Connect (OSTI)

    Catravas, P.; Chattopadhyay, S.; Esarey, E.; Leemans, W.P.; Assmann, R.; Decker, F.-J.; Hogan, M.J.; Iverson, R.; Siemann, R.H.; Walz, D.; Whittum, D.; Blue, B.; Clayton, C.; Joshi, C.; Marsh, K.; Mori, W.B.; Wang, S.; Katsouleas, T.; Lee, S.; Muggli, P.

    2001-01-01

    A method for using Cerenkov radiation near atomic spectral lines to measure plasma source properties for plasma wakefield applications has been discussed and experimentally verified. Because the radiation co-propagates with the electron beam, the radiation samples the source properties exactly along the path of interest with perfect temporal synchronization. Observation wavelengths were chosen with respect to the atomic resonances of the plasma source, where the relative change in the index of refraction strongly affects the Cerenkov cone angle, and permits flexible diagnostic design. The Cerenkov spatial profiles were systematically studied for a Lithium heat pipe oven as a function of oven temperature and observation wavelength. Neutral densities and plasma densities were extracted from the measurements.

  19. Density profiles of plasmas confined by the field of a Levitating Dipole Magnet

    E-Print Network [OSTI]

    Boxer, Alexander C

    2009-01-01

    A 4-channel microwave interferometer (center frequency: 60 GHz) has been constructed to measure the density profiles of plasmas confined within the Levitated Dipole Experiment (LDX). LDX is the first and only experiment ...

  20. Characterization of low-frequency density fluctuations in dipole-confined laboratory plasmas

    E-Print Network [OSTI]

    Ellsworth, Jennifer L

    2010-01-01

    Low-frequency fluctuations of plasma density, floating potential, ion saturation current, visible light intensity, and edge magnetic field are routinely observed in the Levitated Dipole Experiment (LDX). For the purposes ...

  1. Stationary self-focusing of intense laser beam in cold quantum plasma using ramp density profile

    SciTech Connect (OSTI)

    Habibi, M.; Ghamari, F.

    2012-10-15

    By using a transient density profile, we have demonstrated stationary self-focusing of an electromagnetic Gaussian beam in cold quantum plasma. The paper is devoted to the prospects of using upward increasing ramp density profile of an inhomogeneous nonlinear medium with quantum effects in self-focusing mechanism of high intense laser beam. We have found that the upward ramp density profile in addition to quantum effects causes much higher oscillation and better focusing of laser beam in cold quantum plasma in comparison to that in the classical relativistic case. Our computational results reveal the importance and influence of formation of electron density profiles in enhancing laser self-focusing.

  2. Tuning the electron energy by controlling the density perturbation position in laser plasma accelerators

    SciTech Connect (OSTI)

    Brijesh, P.; Thaury, C.; Phuoc, K. T.; Corde, S.; Lambert, G.; Malka, V. [Laboratoire d'Optique Appliquee, ENSTA ParisTech, CNRS UMR7639, Ecole Polytechnique, 91761 Palaiseau (France); Mangles, S. P. D.; Bloom, M.; Kneip, S. [Blackett Laboratory, Imperial College, London SW7 2AZ (United Kingdom)

    2012-06-15

    A density perturbation in an underdense plasma was used to improve the quality of electron bunches produced in the laser-plasma wakefield acceleration scheme. Quasi-monoenergetic electrons were generated by controlled injection in the longitudinal density gradients of the density perturbation. By tuning the position of the density perturbation along the laser propagation axis, a fine control of the electron energy from a mean value of 60 MeV to 120 MeV has been demonstrated with a relative energy-spread of 15 {+-} 3.6%, divergence of 4 {+-} 0.8 mrad, and charge of 6 {+-} 1.8 pC.

  3. COALITION FOR PLASMA SCIENCE Fusion Power Associates

    E-Print Network [OSTI]

    · Materials: brochure, two-pagers, posters. · Web page (plasmacoalition.org): links to plasma sites, evaluated of the CPS web site ­ Ask for input on how to improve web page · Solicit for individual(s) to conduct

  4. Advances and Challenges in Computational Plasma Science

    SciTech Connect (OSTI)

    W.M. Tang; V.S. Chan

    2005-01-03

    Scientific simulation, which provides a natural bridge between theory and experiment, is an essential tool for understanding complex plasma behavior. Recent advances in simulations of magnetically-confined plasmas are reviewed in this paper with illustrative examples chosen from associated research areas such as microturbulence, magnetohydrodynamics, and other topics. Progress has been stimulated in particular by the exponential growth of computer speed along with significant improvements in computer technology.

  5. Plasma density inside a femtosecond laser filament in air: Strong dependence on external focusing

    E-Print Network [OSTI]

    Becker, Andreas

    Plasma density inside a femtosecond laser filament in air: Strong dependence on external focusing generated in air. The control of plasma filament parameters is suitable for many applications such as remote and intense laser pulses in air has stimulated many research interests because of prom- ising applications

  6. 518 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 33, NO. 2, APRIL 2005 Plasma Dynamics During Breakdown in

    E-Print Network [OSTI]

    Kushner, Mark

    , lamp, modeling, plasma. METAL halide arc lamps are widely used sources of in- door and large area518 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 33, NO. 2, APRIL 2005 Plasma Dynamics During plasma hydrodynamics model was used to investigate breakdown in metal halide lamp. Images depicting

  7. 784 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 18. NO. 5, OCTOBER 1990 Temporal Evolution of Plasma From a Highly Ionized

    E-Print Network [OSTI]

    Rocca, Jorge J.

    -3 transitions of HeII has been observed following plasma recombination in a flowing arc jet [9]. However the low784 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 18. NO. 5, OCTOBER 1990 Temporal Evolution of Plasma the temporal ev- olution of a highly ionized helium plasma generated in a l-mm-diameter capillary by a fast (90

  8. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 34, NO. 3, JUNE 2006 855 Kinetics of Plasma Particles and Electron Transport

    E-Print Network [OSTI]

    Kaganovich, Igor

    IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 34, NO. 3, JUNE 2006 855 Kinetics of Plasma Particles and Electron Transport in the Current-Carrying Plasma Adjacent to an Evaporating and Electron Emitting Wall phenomena at a target heated by heat flux from an adjacent plasma in vacuum and in low-pressure discharges

  9. Density profile of strongly correlated spherical Yukawa plasmas

    E-Print Network [OSTI]

    Bonitz, Michael

    by means of local density approximation (LDA) similar to 2D system [6] Usage of the energy density und Astrophysik,Christian-Albrechts-Universit¨at Kiel, D-24118 Kiel, Germany 2 Institut f¨ur Physik, Universit¨at Rostock, D-18051 Rostock, Germany 3 Institut f¨ur Experimentelle und Angewandte Physik

  10. Energy enhancement of proton acceleration in combinational radiation pressure and bubble by optimizing plasma density

    SciTech Connect (OSTI)

    Bake, Muhammad Ali; Xie Baisong [Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Shan Zhang [Department of Mathematics and Physics, Shijiazhuang Tiedao University, Shijiazhuang 050043 (China); Hong Xueren [College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070 (China); Wang Hongyu [Department of Physics, Anshan Normal University, Anshan 114005 (China); Shanghai Bright-Tech Information Technology Co. Ltd, Shanghai 200136 (China)

    2012-08-15

    The combinational laser radiation pressure and plasma bubble fields to accelerate protons are researched through theoretical analysis and numerical simulations. The dephasing length of the accelerated protons bunch in the front of the bubble and the density gradient effect of background plasma on the accelerating phase are analyzed in detail theoretically. The radiation damping effect on the accelerated protons energy is also considered. And it is demonstrated by two-dimensional particle-in-cell simulations that the protons bunch energy can be increased by using the background plasma with negative density gradient. However, radiation damping makes the maximal energy of the accelerated protons a little reduction.

  11. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 34, NO. 3, JUNE 2006 755 Nonequilibrium EEDF in Gas Discharge Plasmas

    E-Print Network [OSTI]

    Kaganovich, Igor

    IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 34, NO. 3, JUNE 2006 755 Nonequilibrium EEDF in Gas Discharge Plasmas Valery A. Godyak, Fellow, IEEE Abstract--Nonequilibrium effects associated with spatial

  12. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 39, NO. 11, NOVEMBER 2011 3103 Helicon Plasma Discharge in a Toroidal

    E-Print Network [OSTI]

    Ji, Hantao

    IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 39, NO. 11, NOVEMBER 2011 3103 Helicon Plasma Discharge of the figures in this paper are available online at http://ieeexplore.ieee.org. Digital Object Identifier 10

  13. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. PS-15, NO. 2, APRIL 1987 Acceleration of Electron-Positron Plasmas to High

    E-Print Network [OSTI]

    Friedland, Lazar

    IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. PS-15, NO. 2, APRIL 1987 Acceleration of Electron is with the Plasma Department, Soreq Nuclear Research Cen- ter, 70600 Yavne, Israel. IEEE Log Number 8613323. 'The

  14. IEEE TRANS. PLASMA SCIENCE, VOL. XX, NO. X, DECEMBER 201X 1 Dust dynamics in magnetic fusion plasmas

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    IEEE TRANS. PLASMA SCIENCE, VOL. XX, NO. X, DECEMBER 201X 1 Dust dynamics in magnetic fusion plasmas: generation, transport, destruction and applications Zhehui Wang, Member, IEEE, Robert Lunsford

  15. FAST observations of VLF waves in the auroral zone: Evidence of very low plasma densities

    E-Print Network [OSTI]

    Strangeway, Robert J.

    FAST observations of VLF waves in the auroral zone: Evidence of very low plasma densities R. J. Peterson,6 E. G. Shelley,6 and R. F. Pfaff,7 Abstract. The Fast Auroral SnapshoT (FAST) explorer frequently-form data acquired by FAST within the auroral density cavity show clear signatures of whistler-mode waves

  16. The National Ignition Facility: Ushering in a new age for high energy density science

    SciTech Connect (OSTI)

    Moses, E. I.; Boyd, R. N.; Remington, B. A.; Keane, C. J.; Al-Ayat, R.

    2009-04-15

    The National Ignition Facility (NIF) [E. I. Moses, J. Phys.: Conf. Ser. 112, 012003 (2008); https://lasers.llnl.gov/], completed in March 2009, is the highest energy laser ever constructed. The high temperatures and densities achievable at NIF will enable a number of experiments in inertial confinement fusion and stockpile stewardship, as well as access to new regimes in a variety of experiments relevant to x-ray astronomy, laser-plasma interactions, hydrodynamic instabilities, nuclear astrophysics, and planetary science. The experiments will impact research on black holes and other accreting objects, the understanding of stellar evolution and explosions, nuclear reactions in dense plasmas relevant to stellar nucleosynthesis, properties of warm dense matter in planetary interiors, molecular cloud dynamics and star formation, and fusion energy generation.

  17. 786 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 34, NO. 3, JUNE 2006 Comparison of Two Microwave and Two Probe

    E-Print Network [OSTI]

    Kaganovich, Igor

    786 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 34, NO. 3, JUNE 2006 Comparison of Two Microwave: cylindrical probe, disk probe, microwave cavity, and microwave hairpin. The measurements are made in hot and cylindrical) and two microwave methods of measuring electron density are compared. In the cases where

  18. Plasma Science & Technology, vo1.7, No.1, Feb. 2005 Recent Results on Field Reversed Configurations from the

    E-Print Network [OSTI]

    Washington at Seattle, University of

    Plasma Science & Technology, vo1.7, No.1, Feb. 2005 Recent Results on Field Reversed ConfigurationsV and high density FRCs have been produced using the standard Field Reversed Theta Pinch (RFTP) method formed in the normal theta pinch manner into the confinement chamber containing the RMF an- tennas

  19. Device and method for electron beam heating of a high density plasma

    DOE Patents [OSTI]

    Thode, Lester E. (Los Alamos, NM)

    1981-01-01

    A device and method for relativistic electron beam heating of a high density plasma in a small localized region. A relativistic electron beam generator produces a high voltage electron beam which propagates along a vacuum drift tube and is modulated to initiate electron bunching within the beam. The beam is then directed through a low density gas chamber which provides isolation between the vacuum modulator and the relativistic electron beam target. The relativistic beam is then applied to a high density target plasma which typically comprises DT, DD, hydrogen boron or similar thermonuclear gas at a density of 10.sup.17 to 10.sup.20 electrons per cubic centimeter. The target plasma is ionized prior to application of the electron beam by means of a laser or other preionization source. Utilizing a relativistic electron beam with an individual particle energy exceeding 3 MeV, classical scattering by relativistic electrons passing through isolation foils is negligible. As a result, relativistic streaming instabilities are initiated within the high density target plasma causing the relativistic electron beam to efficiently deposit its energy into a small localized region within the high density plasma target.

  20. On the breaking of a plasma wave in a thermal plasma. I. The structure of the density singularity

    SciTech Connect (OSTI)

    Bulanov, Sergei V.; Esirkepov, Timur Zh.; Kando, Masaki; Koga, James K.; Pirozhkov, Alexander S.; Nakamura, Tatsufumi; Bulanov, Stepan S.; Schroeder, Carl B.; Esarey, Eric; Califano, Francesco; Pegoraro, Francesco

    2012-11-15

    The structure of the singularity that is formed in a relativistically large amplitude plasma wave close to the wave breaking limit is found by using a simple waterbag electron distribution function. The electron density distribution in the breaking wave has a typical 'peakon' form. The maximum value of the electric field in a thermal breaking plasma is obtained and compared to the cold plasma limit. The results of computer simulations for different initial electron distribution functions are in agreement with the theoretical conclusions. The after-wavebreak regime is then examined, and a semi-analytical model of the density evolution is constructed. Finally the results of two dimensional particle in cell simulations for different initial electron distribution functions are compared, and the role of thermal effects in enhancing particle injection is noted.

  1. PLASMA DYNAMICS AND PLASMA WALL INTERACTION 130 Problems of Atomic Science and Technology. 2006, 6. Series: Plasma Physics (12), p. 130-134

    E-Print Network [OSTI]

    Harilal, S. S.

    PLASMA DYNAMICS AND PLASMA WALL INTERACTION 130 Problems of Atomic Science and Technology. 2006, 6 for the Tokamak reactor concept. The deposited plasma energy causes significant surface erosion, possible structural failure, and frequent plasma contamination. The chamber walls in inertial fusion energy (IFE

  2. Whyte, IAP 2015, MIT MIT Plasma Science & Fusion Center

    E-Print Network [OSTI]

    1 Whyte, IAP 2015, MIT MIT Plasma Science & Fusion Center Fusion Energy: How it works, Why we of light nuclei is the energy source of stars, and basically, the universe #12;4 Whyte, IAP 2015, MIT Fusion is a re-arrangement of nuclei that releases net energy. #12;5 Whyte, IAP 2015, MIT Nuclear

  3. MIT Plasma Science and Fusion Center Design Report

    E-Print Network [OSTI]

    McDonald, Kirk

    P.H. Titus MIT Plasma Science and Fusion Center Design Report MERIT (MERcury Intense Target) BNL be purchased and installed in the cryostat later. The conductor is half inch square, cold worked OFHC copper impregnated. Wound coils of this small radius, using cold worked conductor, retain internal elastic stresses

  4. A new method for determining the plasma electron density using optical frequency comb interferometer

    SciTech Connect (OSTI)

    Arakawa, Hiroyuki Tojo, Hiroshi; Sasao, Hajime; Kawano, Yasunori; Itami, Kiyoshi

    2014-04-15

    A new method of plasma electron density measurement using interferometric phases (fractional fringes) of an optical frequency comb interferometer is proposed. Using the characteristics of the optical frequency comb laser, high density measurement can be achieved without fringe counting errors. Simulations show that the short wavelength and wide wavelength range of the laser source and low noise in interferometric phases measurements are effective to reduce ambiguity of measured density.

  5. The impact of Hall physics on magnetized high energy density plasma jets

    SciTech Connect (OSTI)

    Gourdain, P.-A.; Seyler, C. E.; Atoyan, L.; Greenly, J. B.; Hammer, D. A.; Kusse, B. R.; Pikuz, S. A.; Potter, W. M.; Schrafel, P. C.; Shelkovenko, T. A.

    2014-05-15

    Hall physics is often neglected in high energy density plasma jets due to the relatively high electron density of such jets (n{sub e}???10{sup 19}?cm{sup ?3}). However, the vacuum region surrounding the jet has much lower densities and is dominated by Hall electric field. This electric field redirects plasma flows towards or away from the axis, depending on the radial current direction. A resulting change in the jet density has been observed experimentally. Furthermore, if an axial field is applied on the jet, the Hall effect is enhanced and ignoring it leads to serious discrepancies between experimental results and numerical simulations. By combining high currents (?1 MA) and magnetic field helicity (15° angle) in a pulsed power generator such as COBRA, plasma jets can be magnetized with a 10?T axial field. The resulting field enhances the impact of the Hall effect by altering the density profile of current-free plasma jets and the stability of current-carrying plasma jets (e.g., Z-pinches)

  6. Science Education Group | Princeton Plasma Physics Lab

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust, High-ThroughputUpcoming ReleaseSecurityPediatricNOAA Science Engagement MoveScience

  7. Science literacy | Princeton Plasma Physics Lab

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation ofAlbuquerque| StanfordOffice of Science (SC) SULI Home Science Belowin

  8. 2013 Science Bowl | Princeton Plasma Physics Lab

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-InspiredAtmosphericdevicesPPONeApril 30, 2013 9:30 am -NationalPlasma Camp3Bowl

  9. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL.

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverse (JournalvivoHighHussein KhalilResearch8 IEEE TRANSACTIONS ON PLASMA

  10. Strong self-focusing of a cosh-Gaussian laser beam in collisionless magneto-plasma under plasma density ramp

    SciTech Connect (OSTI)

    Nanda, Vikas; Kant, Niti

    2014-07-15

    The effect of plasma density ramp on self-focusing of cosh-Gaussian laser beam considering ponderomotive nonlinearity is analyzed using WKB and paraxial approximation. It is noticed that cosh-Gaussian laser beam focused earlier than Gaussian beam. The focusing and de-focusing nature of the cosh-Gaussian laser beam with decentered parameter, intensity parameter, magnetic field, and relative density parameter has been studied and strong self-focusing is reported. It is investigated that decentered parameter “b” plays a significant role for the self-focusing of the laser beam as for b=2.12, strong self-focusing is seen. Further, it is observed that extraordinary mode is more prominent toward self-focusing rather than ordinary mode of propagation. For b=2.12, with the increase in the value of magnetic field self-focusing effect, in case of extraordinary mode, becomes very strong under plasma density ramp. Present study may be very useful in the applications like the generation of inertial fusion energy driven by lasers, laser driven accelerators, and x-ray lasers. Moreover, plasma density ramp plays a vital role to enhance the self-focusing effect.

  11. Investigation of physical processes limiting plasma density in H-mode on DIII-D

    SciTech Connect (OSTI)

    Maingi, R.; Mahdavi, M.A.; Jernigan, T.C.

    1996-12-01

    A series of experiments was conducted on the DIII-D tokamak to investigate the physical processes which limit density in high confinement mode (H-mode) discharges. The typical H-mode to low confinement mode (L-mode) transition limit at high density near the empirical Greenwald density limit was avoided by divertor pumping, which reduced divertor neutral pressure and prevented formation of a high density, intense radiation zone (MARFE) near the X-point. It was determined that the density decay time after pellet injection was independent of density relative to the Greenwald limit and increased non-linearly with the plasma current. Magnetohydrodynamic (MHD) activity in pellet-fueled plasmas was observed at all power levels, and often caused unacceptable confinement degradation, except when the neutral beam injected (NBI) power was {le} 3 MW. Formation of MARFEs on closed field lines was avoided with low safety factor (q) operation but was observed at high q, qualitatively consistent with theory. By using pellet fueling and optimizing discharge parameters to avoid each of these limits, an operational space was accessed in which density {approximately} 1.5 {times} Greenwald limit was achieved for 600 ms, and good H-mode confinement was maintained for 300 ms of the density flattop. More significantly, the density was successfully increased to the limit where a central radiative collapse was observed, the most fundamental density limit in tokamaks.

  12. Nonlocal theory of electromagnetic wave decay into two electromagnetic waves in a rippled density plasma channel

    SciTech Connect (OSTI)

    Sati, Priti; Tripathi, V. K.

    2012-12-15

    Parametric decay of a large amplitude electromagnetic wave into two electromagnetic modes in a rippled density plasma channel is investigated. The channel is taken to possess step density profile besides a density ripple of axial wave vector. The density ripple accounts for the momentum mismatch between the interacting waves and facilitates nonlinear coupling. For a given pump wave frequency, the requisite ripple wave number varies only a little w.r.t. the frequency of the low frequency decay wave. The radial localization of electromagnetic wave reduces the growth rate of the parametric instability. The growth rate decreases with the frequency of low frequency electromagnetic wave.

  13. 570 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 16, NO. 5, OCTOBER 1988 A Reflex Electron Beam Discharge as a Plasma

    E-Print Network [OSTI]

    Rocca, Jorge J.

    570 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 16, NO. 5, OCTOBER 1988 A Reflex Electron Beam Discharge as a Plasma Source for Electron Beam Generation Abstract-A reflex electron beam glow discharge has been used as a plasma source for the generation of broad-area electron beams. An electron current

  14. 2250 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 37, NO. 11, NOVEMBER 2009 A Numerical Model of Plasma-Actuator Effects

    E-Print Network [OSTI]

    Huang, Xun

    therein. Most recent ap- plications include high-speed flow control using localized arc filament plasma2250 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 37, NO. 11, NOVEMBER 2009 A Numerical Model of Plasma-Actuator Effects in Flow-Induced Noise Control Ed Peers, Xun Huang, and Xinfu Luo Abstract

  15. 10 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 30, NO. 1, FEBRUARY 2002 Study of Magnetic Helicity Injection via Plasma

    E-Print Network [OSTI]

    Hsu, Scott

    10 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 30, NO. 1, FEBRUARY 2002 Study of Magnetic Helicity Injection via Plasma Imaging Using a High-Speed Digital Camera S. C. Hsu and P. M. Bellan Abstract--The evolution of a plasma generated by a novel planar coaxial gun is photographed using a state

  16. LOCALIZED PLASMA DENSITY ENHANCEMENTS OBSERVED IN STEREO COR1

    SciTech Connect (OSTI)

    Jones, Shaela I.; Davila, Joseph M.

    2009-08-20

    Measurements of solar wind speed in the solar corona, where it is primarily accelerated, have proven elusive. One of the more successful attempts has been the tracking of outward-moving density inhomogeneities in white-light coronagraph images. These inhomogeneities, or 'blobs', have been treated as passive tracers of the ambient solar wind. Here we report on the extension of these observations to lower altitudes using the STEREO COR1 coronagraph, and discuss the implications of these measurements for theories about the origin of these features.

  17. Computational Science and Engineering Certification for Nuclear, Plasma, and Radiological Engineering

    E-Print Network [OSTI]

    Gilbert, Matthew

    Computational Science and Engineering Certification for Nuclear, Plasma, and Radiological Engineering The Computational Science and Engineering certificate program is designed to provide NPRE a certificate in "Computational Science and Engineering", students must complete the required courses listed

  18. Science Undergraduate Laboratory Internship (SULI) | Princeton Plasma

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation ofAlbuquerque| Stanford SynchrotronVideo-ContestHighlightsScienceHasan6,

  19. INSTITUTE OF PHYSICS PUBLISHING PLASMA SOURCES SCIENCE AND TECHNOLOGY Plasma Sources Sci. Technol. 12 (2003) 170181 PII: S0963-0252(03)59585-8

    E-Print Network [OSTI]

    Economou, Demetre J.

    2003-01-01

    discharge are heated by collisional dissipation of wave energy. However, both experimental and theoreticalINSTITUTE OF PHYSICS PUBLISHING PLASMA SOURCES SCIENCE AND TECHNOLOGY Plasma Sources Sci. Technol

  20. COLLOQUIUM: Frontiers in Plasma Science: A High Energy Density Perspective

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory of raregovAboutRecovery ActToolsForNorthfor Gas SeparationsRelevant| Princeton

  1. Effect of electron density profile on power absorption of high frequency electromagnetic waves in plasma

    SciTech Connect (OSTI)

    Xi Yanbin; Liu Yue [MOE Key Laboratory of Materials Modification by Laser, Electron, and Ion Beams, School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)

    2012-07-15

    Considering different typical electron density profiles, a multi slab approximation model is built up to study the power absorption of broadband (0.75-30 GHz) electromagnetic waves in a partially ionized nonuniform magnetized plasma layer. Based on the model, the power absorption spectra for six cases are numerically calculated and analyzed. It is shown that the absorption strongly depends on the electron density fluctuant profile, the background electron number density, and the collision frequency. A potential optimum profile is also analyzed and studied with some particular parameters.

  2. Scattering of electromagnetic waves by vortex density structures associated with interchange instability: Analytical and large scale plasma simulation results

    SciTech Connect (OSTI)

    Sotnikov, V.; Kim, T.; Lundberg, J.; Paraschiv, I.; Mehlhorn, T. A.

    2014-05-15

    The presence of plasma turbulence can strongly influence propagation properties of electromagnetic signals used for surveillance and communication. In particular, we are interested in the generation of low frequency plasma density irregularities in the form of coherent vortex structures. Interchange or flute type density irregularities in magnetized plasma are associated with Rayleigh-Taylor type instability. These types of density irregularities play an important role in refraction and scattering of high frequency electromagnetic signals propagating in the earth ionosphere, in high energy density physics, and in many other applications. We will discuss scattering of high frequency electromagnetic waves on low frequency density irregularities due to the presence of vortex density structures associated with interchange instability. We will also present particle-in-cell simulation results of electromagnetic scattering on vortex type density structures using the large scale plasma code LSP and compare them with analytical results.

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

    SciTech Connect (OSTI)

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

    2014-07-15

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

  4. IEEE TRANSACTIONSON PLASMA SCIENCE,VOL. 21, NO. 1, FEBRUARY 1993 Phase-Matched Third Harmonic

    E-Print Network [OSTI]

    IEEE TRANSACTIONSON PLASMA SCIENCE,VOL. 21, NO. 1, FEBRUARY 1993 ~ 105 Phase-Matched Third Harmonic-AC02- The authors are with the Plasma Physics Laboratory, Princeton University, IEEE Log Number 9206344

  5. Magnetic topology and current channels in plasmas with toroidal current density inversions

    SciTech Connect (OSTI)

    Ciro, D.; Caldas, I. L. [Departamento de Física Aplicada, Universidade de São Paulo, 05508-090 São Paulo (Brazil)] [Departamento de Física Aplicada, Universidade de São Paulo, 05508-090 São Paulo (Brazil)

    2013-10-15

    The equilibrium magnetic field inside axisymmetric plasmas with inversions on the toroidal current density is considered. Previous works have shown that internal regions with negative current density lead to non-nested magnetic surfaces inside the plasma. Following these results, we derive a general expression relating the positive and negative currents inside the non-nested surfaces. This is done in terms of an anisotropy parameter that is model-independent and is based in very general properties of the magnetic field. We demonstrate that the positive currents in axisymmetric islands screen the negative one in the plasma center by reaching about twice its magnitude. Further, we illustrate these results by developing a family of analytical local solutions for the poloidal magnetic field in a region of interest that contains the inverted current. These local solutions exhibit non-nested magnetic surfaces with a combined current of at least twice the magnitude of the negative one, as prescribed from the topological arguments, and allow to study topological transitions driven by geometrical changes in the current profile. To conclude, we discuss the signatures of internal current density inversions in a confinement device and show that magnetic pitch measurements may be inappropriate to differentiate current reversals and small current holes in plasmas.

  6. Effects of a random spatial variation of the plasma density on the mode conversion in cold, unmagnetized, and stratified plasmas

    SciTech Connect (OSTI)

    Jung Yu, Dae; Kim, Kihong

    2013-12-15

    We study the effects of a random spatial variation of the plasma density on the mode conversion of electromagnetic waves into electrostatic oscillations in cold, unmagnetized, and stratified plasmas. Using the invariant imbedding method, we calculate precisely the electromagnetic field distribution and the mode conversion coefficient, which is defined to be the fraction of the incident wave power converted into electrostatic oscillations, for the configuration where a numerically generated random density variation is added to the background linear density profile. We repeat similar calculations for a large number of random configurations and take an average of the results. We obtain a peculiar nonmonotonic dependence of the mode conversion coefficient on the strength of randomness. As the disorder increases from zero, the maximum value of the mode conversion coefficient decreases initially, then increases to a maximum, and finally decreases towards zero. The range of the incident angle in which mode conversion occurs increases monotonically as the disorder increases. We present numerical results suggesting that the decrease of mode conversion mainly results from the increased reflection due to the Anderson localization effect originating from disorder, whereas the increase of mode conversion of the intermediate disorder regime comes from the appearance of many resonance points and the enhanced tunneling between the resonance points and the cutoff point. We also find a very large local enhancement of the magnetic field intensity for particular random configurations. In order to obtain high mode conversion efficiency, it is desirable to restrict the randomness close to the resonance region.

  7. Modelling of the internal dynamics and density in a tens of joules plasma focus device

    SciTech Connect (OSTI)

    Marquez, Ariel; Gonzalez, Jose; Tarifeno-Saldivia, Ariel; Pavez, Cristian; Soto, Leopoldo; Clausse, Alejandro

    2012-01-15

    Using MHD theory, coupled differential equations were generated using a lumped parameter model to describe the internal behaviour of the pinch compression phase in plasma focus discharges. In order to provide these equations with appropriate initial conditions, the modelling of previous phases was included by describing the plasma sheath as planar shockwaves. The equations were solved numerically, and the results were contrasted against experimental measurements performed on the device PF-50J. The model is able to predict satisfactorily the timing and the radial electron density profile at the maximum compression.

  8. Generation of terahertz radiation from a low-density plasma slab irradiated by a laser pulse

    SciTech Connect (OSTI)

    Frolov, A. A. [Russian Academy of Sciences, Joint Institute for High Temperatures (Russian Federation)

    2010-04-15

    The generation of terahertz electromagnetic radiation when a laser pulse propagates through a low-density plasma slab is considered. It is shown that terahertz waves are excited because of the growth of a weakly damped, antisymmetric leaking mode of the plasma slab. The spectral, angular, and energy parameters of the terahertz radiation are investigated, as well as the spatiotemporal structure of the emitted waves. It is demonstrated that terahertz electromagnetic wave fields are generated most efficiently when the pulse length is comparable to the slab thickness.

  9. Simulation Study of an Extended Density DC Glow Toroidal Plasma Source

    SciTech Connect (OSTI)

    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.

    2006-12-04

    Conventional wisdom assigns the DC glow discharge regime to plasma currents below {approx}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.

  10. Experimental and Computational Studies of High Energy Density Plasma Streams Ablated from Fine Wires

    SciTech Connect (OSTI)

    Greenly, John B. [Cornell University; Seyler, Charles [Cornell University

    2014-03-30

    Experimental and computational studies of high energy density plasma streams ablated from fine wires. Laboratory of Plasma Studies, School of Electrical and Computer Engineering, Cornell University. Principal Investigators: Dr. John B. Greenly and Dr. Charles E. Seyler. This report summarizes progress during the final year of this project to study the physics of high energy density (HED) plasma streams of 10^17-10^20/cm3 density and high velocity (~100-500 km/s). Such streams are produced from 5-250 micrometer diameter wires heated and ionized by a 1 MA, 250 ns current pulse on the COBRA pulsed power facility at Cornell University. Plasma is ablated from the wires and is driven away to high velocity by unbalanced JxB force. A wire, or an array of wires, can persist as an essentially stationary, continuous source of this streaming plasma for >200 ns, even with driving magnetic fields of many Tesla and peak current densities in the plasma of many MA/cm2. At the heart of the ablation stream generation is the continuous transport of mass from the relatively cold, near-solid-density wire "core" into current-carrying plasma within 1 mm of the wire, followed by the magnetic acceleration of that plasma and its trapped flux to form a directed stream. In the first two years of this program, an advancing understanding of ablation physics led to the discovery of several novel wire ablation experimental regimes. In the final year, one of these new HED plasma regimes has been studied in quantitative detail. This regime studies highly reproducible magnetic reconnection in strongly radiating plasma with supersonic and superalfvenic flow, and shock structures in the outflow. The key discovery is that very heavy wires, e.g. 250 micrometer diameter Al or 150 micrometer Cu, behave in a qualitatively different way than the lighter wires typically used in wire-array Z-pinches. Such wires can be configured to produce a static magnetic X-point null geometry that stores magnetic and thermal energy; reconnection and outflow are triggered when the current begins to decrease and the electric field reverses. The reconnecting flow is driven by both magnetic and thermal pressure forces, and it has been found to be possible to vary the configuration so that one or the other dominates. The magnetic null extends into a current sheet that is heated and radiates strongly, with supersonic outflows. This is the first study of reconnection in this HED plasma regime. This compressible, radiative regime, and the triggering mechanism, may be relevant to solar and astrophysical processes. The PERSEUS extended MHD code has been developed for simulation of these phenomena, and will continue to be used and further developed to help interpret and understand experimental results, as well as to guide experimental design. The code is well-suited to simulations of shocks, and includes Hall and electron inertia physics that appear to be of importance in a number of ablation flow regimes, and definitely in the reconnection regime when gradient scales are comparable to the ion inertial scale. During the final year, our graduate student supported by this grant completed a new version of PERSEUS with the finite volume computational scheme replaced by a discontinuous Galerkin method that gives much less diffusive behavior and allows faster run time and higher spatial resolution. Thecode is now being used to study shock structures produced in the outflow region of the reconnection regime.

  11. Current initiation in low-density foam z-pinch plasmas

    SciTech Connect (OSTI)

    Derzon, M.; Nash, T.; Allshouse, G. [and others

    1996-07-01

    Low density agar and aerogel foams were tested as z-pinch loads on the SATURN accelerator. In these first experiments, we studied the initial plasma conditions by measuring the visible emission at early times with a framing camera and 1-D imaging. At later time, near the stagnation when the plasma is hotter, x-ray imaging and spectral diagnostics were used to characterize the plasma. Filamentation and arcing at the current contacts was observed. None of the implosions were uniform along the z-axis. The prime causes of these problems are believed to be the electrode contacts and the current return configuration and these are solvable. Periodic phenomena consistent with the formation of instabilities were observed on one shot, not on others, implying that there may be a way of controlling instabilities in the pinch. Many of the issues involving current initiation may be solvable. Solutions are discussed.

  12. The response of plasma density to breaking inertial gravity wave in the lower regions of ionosphere

    SciTech Connect (OSTI)

    Tang, Wenbo Mahalov, Alex

    2014-04-15

    We present a three-dimensional numerical study for the E and lower F region ionosphere coupled with the neutral atmosphere dynamics. This model is developed based on a previous ionospheric model that examines the transport patterns of plasma density given a prescribed neutral atmospheric flow. Inclusion of neutral dynamics in the model allows us to examine the charge-neutral interactions over the full evolution cycle of an inertial gravity wave when the background flow spins up from rest, saturates and eventually breaks. Using Lagrangian analyses, we show the mixing patterns of the ionospheric responses and the formation of ionospheric layers. The corresponding plasma density in this flow develops complex wave structures and small-scale patches during the gravity wave breaking event.

  13. Electron density and temperature measurement by continuum radiation emitted from weakly ionized atmospheric pressure plasmas

    SciTech Connect (OSTI)

    Park, Sanghoo; Choe, Wonho, E-mail: wchoe@kaist.ac.kr [Department of Physics, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Youn Moon, Se [High-enthalpy Plasma Research Center, Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju 561-756 (Korea, Republic of); Park, Jaeyoung [5771 La Jolla Corona Drive, La Jolla, CA 92037 (United States)

    2014-02-24

    The electron-atom neutral bremsstrahlung continuum radiation emitted from weakly ionized plasmas is investigated for electron density and temperature diagnostics. The continuum spectrum in 450–1000?nm emitted from the argon atmospheric pressure plasma is found to be in excellent agreement with the neutral bremsstrahlung formula with the electron-atom momentum transfer cross-section given by Popovi?. In 280–450?nm, however, a large discrepancy between the measured and the neutral bremsstrahlung emissivities is observed. We find that without accounting for the radiative H{sub 2} dissociation continuum, the temperature, and density measurements would be largely wrong, so that it should be taken into account for accurate measurement.

  14. High-Density Plasma Arc Heating Studies of FePt Thin Films

    SciTech Connect (OSTI)

    Cole, Amanda C; Thompson, Gregory; Harrell, J. W.; Weston, James; Ott, Ronald D

    2006-01-01

    The effect of pulsed-thermal-processing with high-density plasma arc heating is discussed for 20 nm thick nanocrystalline FePt thin films. The dependence of the A1 {yields} L1{sub 0} phase transformation on pulsed time and radiant energy of the pulse is quantified through x-ray diffraction and alternating gradient magnetometry. For 100 ms and 250 ms pulse widths, the phase transformation was observed. Higher radiant energy densities resulted in a larger measured coercivity associated with the L1{sub 0} phase.

  15. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 38, NO. 12, DECEMBER 2010 3265 Combustion Dynamics of Plasma-Enhanced

    E-Print Network [OSTI]

    Lee, Tonghun

    -induced fluorescence images of hydroxyl (OH) and carbon monoxide (CO) radicals are obtained over a range of equivalence are significantly influenced by in situ fuel reforming at higher plasma powers. Index Terms--Carbon monoxide, fuelIEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 38, NO. 12, DECEMBER 2010 3265 Combustion Dynamics

  16. Stable Electron Beams With Low Absolute Energy Spread From a Laser Wakefield Accelerator With Plasma Density Ramp Controlled Injection

    E-Print Network [OSTI]

    Geddes, Cameron Guy Robinson

    -keV level energy spread and central energy sta- bility by using the plasma density profile to control self is reached. Because dephasing limits electron energy gain [2], low densities ( to order of 100 keV at GeV energies and beyond. RESULTS In the present experiments, the density profile

  17. Metrology Challenges for High Energy Density Science Target Manufacture

    SciTech Connect (OSTI)

    Seugling, R M; Bono, M J; Davis, P

    2009-02-19

    Currently, High Energy Density Science (HEDS) experiments are used to support and qualify predictive physics models. These models assume ideal conditions such as energy (input) and device (target) geometry. The experiments rely on precision targets constructed from components with dimensions in the millimeter range, while having micrometer-scale, functional features, including planar steps, sine waves, and step-joint geometry on hemispherical targets. Future target designs will likely have features and forms that rival or surpass current manufacturing and characterization capability. The dimensional metrology of these features is important for a number of reasons, including qualification of sub-components prior to assembly, quantification of critical features on the as-built assemblies and as a feedback mechanism for fabrication process development. Variations in geometry from part to part can lead to functional limitations, such as unpredictable instabilities during an experiment and the inability to assemble a target from poorly matched sub-components. Adding to the complexity are the large number and variety of materials, components, and shapes that render any single metrology technique difficult to use with low uncertainty. Common materials include metal and glass foams, doped transparent and opaque plastics and a variety of deposited and wrought metals. A suite of metrology tools and techniques developed to address the many critical issues relevant to the manufacture of HEDS targets including interferometry, x-ray radiography and contact metrology are presented including two sided interferometry for absolute thickness metrology and low force probe technology for micrometer feature coordinate metrology.

  18. J. A. Snipes, 2nd Workshop on Burning Plasma Science, 1 3 May 2001 San Diego

    E-Print Network [OSTI]

    J. A. Snipes, 2nd Workshop on Burning Plasma Science, 1 ­ 3 May 2001 San Diego H-mode Threshold San Diego Global H-mode Threshold Analysis The global regressions to the H-mode threshold power based in JET. #12;J. A. Snipes, 2nd Workshop on Burning Plasma Science, 1 ­ 3 May 2001 San Diego #12;J. A

  19. Age distribution of scientists at the MIT Plasma Science and Fusion Center.

    E-Print Network [OSTI]

    Age distribution of scientists at the MIT Plasma Science and Fusion Center. University Programs. Based on a survey of the age distribution of scientists at MIT's Plasma Science and Fusion Center, the figure shows a two-humped distribution; the first peak, around age 30, is mainly post-docs and junior

  20. COLD BUBBLE FORMATION DURING TOKAMAK DENSITY LIMIT DISRUPTIONS

    E-Print Network [OSTI]

    Howard, John

    COLD BUBBLE FORMATION DURING TOKAMAK DENSITY LIMIT DISRUPTIONS J. HOWARD, M. PERSSON* Plasma Research Laboratory, Research School of Physical Sciences, Australian National University, Canberra

  1. Effect of low density H-mode operation on edge and divertor plasma parameters

    SciTech Connect (OSTI)

    Maingi, R. [Oak Ridge Associated Universities, Inc., TN (United States); Mioduszewski, P.K. [Oak Ridge National Lab., TN (United States); Cuthbertson, J.W. [Sandia National Labs., Albuquerque, NM (United States)] [and others

    1994-07-01

    We present a study of the impact of H-mode operation at low density on divertor plasma parameters on the DIII-D tokamak. The line-average density in H-mode was scanned by variation of the particle exhaust rate, using the recently installed divertor cryo-condensation pump. The maximum decrease (50%) in line-average electron density was accompanied by a factor of 2 increase in the edge electron temperature, and 10% and 20% reductions in the measured core and divertor radiated power, respectively. The measured total power to the inboard divertor target increased by a factor of 3, with the major contribution coming from a factor of 5 increase in the peak heat flux very close to the inner strike point. The measured increase in power at the inboard divertor target was approximately equal to the measured decrease in core and divertor radiation.

  2. Fast magnetic reconnection in low-density electron-positron plasmas

    SciTech Connect (OSTI)

    Bessho, Naoki; Bhattacharjee, A.

    2010-10-15

    Two-dimensional particle-in-cell simulations have been performed to study magnetic reconnection in low-density electron-positron plasmas without a guide magnetic field. Impulsive reconnection rates become of the order of unity when the background density is much smaller than 10% of the density in the initial current layer. It is demonstrated that the outflow speed is less than the upstream Alfven speed, and that the time derivative of the density must be taken into account in the definition of the reconnection rate. The reconnection electric fields in the low-density regime become much larger than the ones in the high-density regime, and it is possible to accelerate the particles to high energies more efficiently. The inertial term in the generalized Ohm's law is the most dominant term that supports a large reconnection electric field. An effective collisionless resistivity is produced and tracks the extension of the diffusion region in the late stage of the reconnection dynamics, and significant broadening of the diffusion region is observed. Because of the broadening of the diffusion region, no secondary islands, which have been considered to play a role to limit the diffusion region, are generated during the extension of the diffusion region in the outflow direction.

  3. Organization by Gordon Research Conferences of the 2012 Plasma Processing Science Conference 22-27 July 2012

    SciTech Connect (OSTI)

    Jane Chang

    2012-07-27

    The 2012 Gordon Research Conference on Plasma Processing Science will feature a comprehensive program that will highlight the most cutting edge scientific advances in plasma science and technology as well as explore the applications of this nonequilibrium medium in possible approaches relative to many grand societal challenges. Fundamental science sessions will focus on plasma kinetics and chemistry, plasma surface interactions, and recent trends in plasma generation and multi-phase plasmas. Application sessions will explore the impact of plasma technology in renewable energy, the production of fuels from renewable feedstocks and carbon dioxide neutral solar fuels (from carbon dioxide and water), and plasma-enabled medicine and sterilization.

  4. Plasma-Density Determination from X-Ray Radiography of Laser-Driven Spherical Implosions F. J. Marshall, P. W. McKenty, J. A. Delettrez, R. Epstein, J. P. Knauer, and V. A. Smalyuk

    E-Print Network [OSTI]

    to sampling the areal density at the time of fusion particle production. In non-igniting capsules, the cold, R. D. Petrasso, and F. H. Se´guin Plasma Science and Fusion Center, Massachusetts Institute confinement fusion (ICF) relies on the com- pression of spherical targets by means of a high power driver

  5. A comparison of parametric decay of oblique Langmuir wave in high and low density magneto-plasmas

    SciTech Connect (OSTI)

    Shahid, M.; Hussain, A.; Department of Physics, Government College University, Lahore-54000 ; Murtaza, G.

    2013-09-15

    The parametric decay instability of an obliquely propagating Langmuir wave into the low-frequency electromagnetic shear Alfven wave and the Left-Handed Circularly Polarized wave has been investigated in an electron-ion plasma, immersed in a uniform external magnetic field. Quantum magneto-hydrodynamic model has been used to find the linear and non-linear response of a high density quantum magneto-plasma. Going to the classical limit (??0) retrieves the results for low density classical plasma. Nonlinear dispersion relations and growth rates are derived with analytically and numerically. It is observed that growth rate in the high density degenerate magneto-plasma increases exponentially, while in the low density classical case it increases logarithmically.

  6. Device and method for relativistic electron beam heating of a high-density plasma to drive fast liners

    DOE Patents [OSTI]

    Thode, Lester E. (Los Alamos, NM)

    1981-01-01

    A device and method for relativistic electron beam heating of a high-density plasma in a small localized region. A relativistic electron beam generator or accelerator produces a high-voltage electron beam which propagates along a vacuum drift tube and is modulated to initiate electron bunching within the beam. The beam is then directed through a low-density gas chamber which provides isolation between the vacuum modulator and the relativistic electron beam target. The relativistic beam is then applied to a high-density target plasma which typically comprises DT, DD, hydrogen boron or similar thermonuclear gas at a density of 10.sup.17 to 10.sup.20 electrons per cubic centimeter. The target gas is ionized prior to application of the electron beam by means of a laser or other preionization source to form a plasma. Utilizing a relativistic electron beam with an individual particle energy exceeding 3 MeV, classical scattering by relativistic electrons passing through isolation foils is negligible. As a result, relativistic streaming instabilities are initiated within the high-density target plasma causing the relativistic electron beam to efficiently deposit its energy and momentum into a small localized region of the high-density plasma target. Fast liners disposed in the high-density target plasma are explosively or ablatively driven to implosion by a heated annular plasma surrounding the fast liner which is generated by an annular relativistic electron beam. An azimuthal magnetic field produced by axial current flow in the annular plasma, causes the energy in the heated annular plasma to converge on the fast liner.

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

    E-Print Network [OSTI]

    Kushner, Mark

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

  8. Test particle simulation of direct laser acceleration in a density-modulated plasma waveguide

    SciTech Connect (OSTI)

    Lin, M.-W.; Jovanovic, I.

    2012-11-15

    Direct laser acceleration (DLA) of electrons by the use of the intense axial electric field of an ultrafast radially polarized laser pulse is a promising technique for future compact accelerators. Density-modulated plasma waveguides can be implemented for guiding the propagation of the laser pulse to extend the acceleration distance and for the quasi-phase-matching between the accelerated electrons and the laser pulse. A test particle model is developed to study the optimal axial density modulation structure of plasma waveguides for laser pulses to efficiently accelerate co-propagating electrons. A simple analytical approach is also presented, which can be used to estimate the energy gain in DLA. The analytical model is validated by the test particle simulation. The effect of injection phase and acceleration of electrons injected at various radial positions are studied. The results indicate that a positively chirped density modulation of the waveguide structure is required to accelerate electron with low initial energies, and can be effectively optimized. A wider tolerance on the injection phase and radial distance from the waveguide axis exists for electrons injected with a higher initial energy.

  9. MIT Plasma Science & Fusion Center: research, alcator, publications...

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

    Plasma Technology Useful Links Presentations from the 45th Annual Meeting of the APS Division of Plasma Physics, Albuquerque, 2003 Invited Orals D. Ernst Role of Trapped...

  10. MIT Plasma Science & Fusion Center: research, alcator, publications...

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

    & Engineering Plasma Technology Waves & Beams Useful Links 49th Annual Meeting of the APS Division of Plasma Physics, Orlando, 2007 Invited Orals P. Bonoli Lower Hybrid Current...

  11. Numerical Studies of Electron Acceleration Behind Self-Modulating Proton Beam in Plasma with a Density Gradient

    E-Print Network [OSTI]

    Petrenko, Alexey; Sosedkin, Alexander

    2015-01-01

    Presently available high-energy proton beams in circular accelerators carry enough momentum to accelerate high-intensity electron and positron beams to the TeV energy scale over several hundred meters of the plasma with a density of about 1e15 1/cm^3. However, the plasma wavelength at this density is 100-1000 times shorter than the typical longitudinal size of the high-energy proton beam. Therefore the self-modulation instability (SMI) of a long (~10 cm) proton beam in the plasma should be used to create the train of micro-bunches which would then drive the plasma wake resonantly. Changing the plasma density profile offers a simple way to control the development of the SMI and the acceleration of particles during this process. We present simulations of the possible use of a plasma density gradient as a way to control the acceleration of the electron beam during the development of the SMI of a 400 GeV proton beam in a 10 m long plasma. This work is done in the context of the AWAKE project --- the proof-of-prin...

  12. IOP PUBLISHING PLASMA SOURCES SCIENCE AND TECHNOLOGY Plasma Sources Sci. Technol. 16 (2007) 832838 doi:10.1088/0963-0252/16/4/019

    E-Print Network [OSTI]

    2007-01-01

    IOP PUBLISHING PLASMA SOURCES SCIENCE AND TECHNOLOGY Plasma Sources Sci. Technol. 16 (2007) 832 of droplets which are ejected from the molten metal at the wire tip by an electric pinch propelling them

  13. Electron density diagnostic for hot plasmas in coronal regime by using B-like ions

    E-Print Network [OSTI]

    Guiyun Liang; Gang Zhao

    2008-03-14

    Line ratio of $3d-2p$ transition lines in boron-like spectra of Si X, S XII, Ar XIV and Fe XXII has been investigated. Collisional-radiative model calculations reveal that the line ratio is sensitive to the electron density in ranges of $n_{\\rm e}=4.0\\times10^7-3.0\\times10^{10}$ cm$^{-3}$, $4.0\\times10^8-3.0\\times10^{11}$ cm$^{-3}$, $3.0\\times10^9-4.0\\times10^{12}$ cm$^{-3}$ and $2.0\\times10^{12}-3.0\\times10^{15}$ cm$^{-3}$, respectively. This complements the K-shell diagnostics of helium-like ions. By comparison between the prediction and the measured values, effective electron densities in the electron beam ion trap (EBIT) plasmas performed by Lepson and collaborators at Lawrence Livermore EBIT, are estimated to be $n_{\\rm e}=3.4^{+0.8}_{-0.6}\\times10^{10}$ cm$^{-3}$ and $5.6^{+1.0}_{-1.1}\\times10^{10}$ cm$^{-3}$ for sulphur and argon plasmas. In case of argon, a good agreement is shown with the actual electron density derived from N VI K-shell spectrum. We further explore the $3d-2p$ transition lines of Si X and S XII in the stellar coronal spectra measured with the Low Energy Transmission Grating Spectrometer combined with High Resolution Camera on board the {\\it Chandra X-ray Observatory}. The constrained electron densities show a good agreement with the those determined from C V and O VII K-shell spectra.

  14. Results from the Levitated Dipole Experiment MIT Plasma Science and Fusion Center

    E-Print Network [OSTI]

    1 Results from the Levitated Dipole Experiment J. Kesner MIT Plasma Science and Fusion Center D December 15, 2011 Columbia University #12;FES: Advance the fundamental science of magnetically confined lead naturally to breadth in science and technology · Example: Confinement in the field of a levitated

  15. Understanding the dramatic role of anomalous dispersion on the measurement of electron densities in plasmas using interferometers

    SciTech Connect (OSTI)

    Nilsen, J; Johnson, W R; Iglesias, C A; Scofield, J H

    2005-07-20

    For decades the electron density of plasmas has been measured using optical interferometers. With the availability of good X-ray laser sources in the last decade interferometers have been extended into the wavelength range 14-47 nm, which has enabled researchers to probe even higher density plasmas. The data analysis assumes the index of refraction is due only to the free electrons, which makes the index less than one. Recent interferometer experiments in Al plasmas observed plasmas with index of refraction greater than one at 14 nm and brought into question the validity of the usual formula for calculating the index. In this paper we show how the anomalous dispersion from bound electrons can dominate the free electron contribution to the index of refraction in many plasmas and make the index greater than one or enhance the contribution to the index such that one would greatly overestimate the density of the plasma using interferometers. Using a new average-atom code we calculate the index of refraction in many plasmas at different temperatures for photon energies from 0 to 100 eV and compare against calculations done with OPAL. We also present examples of other plasmas that may have index of refraction greater than one at X-ray laser energies. During the next decade X-ray free electron lasers and other X-ray sources will be available to probe a wider variety of plasmas at higher densities and shorter wavelengths so understanding the index of refraction in plasmas will be even more essential.

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

    SciTech Connect (OSTI)

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

    2014-03-15

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

  17. Transition from order to chaos, and density limit, in magnetized plasmas

    SciTech Connect (OSTI)

    Carati, A.; Maiocchi, A.; Marino, M.; Galgani, L.; Zuin, M.; Martines, E.

    2012-09-15

    It is known that a plasma in a magnetic field, conceived microscopically as a system of point charges, can exist in a magnetized state, and thus remain confined, inasmuch as it is in an ordered state of motion, with the charged particles performing gyrational motions transverse to the field. Here, we give an estimate of a threshold, beyond which transverse motions become chaotic, the electrons being unable to perform even one gyration, so that a breakdown should occur, with complete loss of confinement. The estimate is obtained by the methods of perturbation theory, taking as perturbing force acting on each electron that due to the so-called microfield, i.e., the electric field produced by all the other charges. We first obtain a general relation for the threshold, which involves the fluctuations of the microfield. Then, taking for such fluctuations, the formula given by Iglesias, Lebowitz, and MacGowan for the model of a one component plasma with neutralizing background, we obtain a definite formula for the threshold, which corresponds to a density limit increasing as the square of the imposed magnetic field. Such a theoretical density limit is found to fit pretty well the empirical data for collapses of fusion machines.

  18. WAVE-ENERGY DENSITY AND WAVE-MOMENTUM DENSITY OF EACH SPECIES OF A COLLISION-LESS PLASMA

    E-Print Network [OSTI]

    Cary, John R.

    2012-01-01

    A LiBRARY ANL WAVE-ENERGY DENSITY AND WAVE-MOMENTUM DENSITYof Califomia. To be in WAVE-ENERGY DENSITY AND WAVE~HOMENTUMExpress1ons for the wave-energy density and wave-momentum

  19. Ed Synakowski Associate Director, Office of Science

    E-Print Network [OSTI]

    Ed Synakowski Associate Director, Office of Science Fusion Energy Sciences The charge for advice on strategic planning Presented to FESAC April 9, 2014 http://science.energy.gov/fes #12;The Office of Science, and pulse lengths; · Discovery Plasma Science ­ the study of laboratory plasmas and the high energy density

  20. The National Ignition Facility: A New Era in High Energy Density Science

    SciTech Connect (OSTI)

    Moses, E

    2009-06-10

    The National Ignition Facility, the world's most energetic laser system, is now operational. This talk will describe NIF, the ignition campaign, and new opportunities in fusion energy and high energy density science enabled by NIF.

  1. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 39, NO. 4, APRIL 2011 1007 Inertial Confinement Fusion Using

    E-Print Network [OSTI]

    IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 39, NO. 4, APRIL 2011 1007 Inertial Confinement Fusion in this paper are available online at http://ieeexplore.ieee.org. Digital Object Identifier 10.1109/TPS.2011

  2. IEEE TRANSACTIONS PLASMA SCIENCE, VOL. JUNE SpaceCharge Effects on Multipactor on Dielectric

    E-Print Network [OSTI]

    Wurtele, Jonathan

    IEEE TRANSACTIONS PLASMA SCIENCE, VOL. JUNE Space­Charge Effects on Multipactor on Dielectric Agust Valfells, John Verboncoeur, Lau, Member, IEEE Abstract---This paper analyzes effects space charge shielding

  3. MIT Plasma Science & Fusion Center: research, alcator, publications...

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

    of Lower Hybrid Wave Propagation in the Edge Plasma of a Tokamak D. Brunner Plasma Sheath Heat Flux Transmission in the Alcator C-Mod Divertor M. Garrett ICRF Antenna Design...

  4. Low Temperature Plasma Science: Not Only the Fourth State of Matter but All of Them. Report of the Department of Energy Office of Fusion Energy Sciences Workshop on Low Temperature Plasmas, March 25-57, 2008

    SciTech Connect (OSTI)

    2008-09-01

    Low temperature plasma science (LTPS) is a field on the verge of an intellectual revolution. Partially ionized plasmas (often referred to as gas discharges) are used for an enormous range of practical applications, from light sources and lasers to surgery and making computer chips, among many others. The commercial and technical value of low temperature plasmas (LTPs) is well established. Modern society would simply be less advanced in the absence of LTPs. Much of this benefit has resulted from empirical development. As the technology becomes more complex and addresses new fields, such as energy and biotechnology, empiricism rapidly becomes inadequate to advance the state of the art. The focus of this report is that which is less well understood about LTPs - namely, that LTPS is a field rich in intellectually exciting scientific challenges and that addressing these challenges will result in even greater societal benefit by placing the development of plasma technologies on a solid science foundation. LTPs are unique environments in many ways. Their nonequilibrium and chemically active behavior deviate strongly from fully ionized plasmas, such as those found in magnetically confined fusion or high energy density plasmas. LTPs are strongly affected by the presence of neutral species-chemistry adds enormous complexity to the plasma environment. A weakly to partially ionized gas is often characterized by strong nonequilibrium in the velocity and energy distributions of its neutral and charged constituents. In nonequilibrium LTP, electrons are generally hot (many to tens of electron volts), whereas ions and neutrals are cool to warm (room temperature to a few tenths of an electron volt). Ions and neutrals in thermal LTP can approach or exceed an electron volt in temperature. At the same time, ions may be accelerated across thin sheath boundary layers to impact surfaces, with impact energies ranging up to thousands of electron volts. These moderately energetic electrons can efficiently create reactive radical fragments and vibrationally and electronically excited species from collisions with neutral molecules. These chemically active species can produce unique structures in the gas phase and on surfaces, structures that cannot be produced in other ways, at least not in an economically meaningful way. Photons generated by electron impact excited species in the plasma can interact more or less strongly with other species in the plasma or with the plasma boundaries, or they can escape from the plasma. The presence of boundaries around the plasma creates strong gradients where plasma properties change dramatically. It is in these boundary regions where externally generated electromagnetic radiation interacts most strongly with the plasma, often producing unique responses. And it is at bounding surfaces where complex plasma-surface interactions occur. The intellectual challenges associated with LTPS center on several themes, and these are discussed in the chapters that follow this overview. These themes are plasma-surface interactions; kinetic, nonlinear properties of LTP; plasmas in multiphase media; scaling laws for LTP; and crosscutting themes: diagnostics, modeling, and fundamental data.

  5. MIT Plasma Science & Fusion Center: research

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

    Research Program Information Publications & News Meetings & Seminars Contact Information Physics Research Fusion Technology & Engineering Plasma Technology Waves & Beams Useful...

  6. LLNL-MI-519991 International Collaboration on Plasma Science and Control

    E-Print Network [OSTI]

    -state plasma confinement and control science; and in plasma-wall interactions. The following are a set, such as in long-pulse, steady-state research in superconducting advanced tokamaks and stellarators; in steady.g., the international superconducting tokamaks. The US national teams could be formed into projects with participation

  7. 167Connection Science, Vol. 7, No. 2, 1995 Density Plots of Hidden Value Unit Activations

    E-Print Network [OSTI]

    Dawson, Michael

    167Connection Science, Vol. 7, No. 2, 1995 Density Plots of Hidden Value Unit Activations Reveal backpropagation network, called a network of value units, was trained to detect problem type and validity of a set. After training was success- fully completed, jittered density plots were computed for each hidden unit

  8. 2392 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 39, NO. 1, NOVEMBER 2011 Evolution of MHD Instabilities in Plasma

    E-Print Network [OSTI]

    Kroupp, Eyal

    the azimuthal magnetic field resulting from axially driven high currents. In this process, acceleration-driven fusion and the study of matter under high energy density [1]. In such systems, a cylindrical plasma) and the cylindrical anode was 9.5 mm. Planar laser-induced fluores- cence measurements on a similar system

  9. Sean Finnegan & Ann Satsangi Fusion Energy Sciences

    E-Print Network [OSTI]

    meter (e.g., the energy density of a hydrogen molecule). This corresponds to a pressure of approximately Associates15 December 2011 Comments on the DOE-SC Program in High Energy Density Laboratory Plasma Science research community in High Energy Density Laboratory Plasma (HEDLP) science including Inertial Fusion

  10. Magnetic reconnection in high-energy-density laser-produced plasmas

    SciTech Connect (OSTI)

    Fox, W.; Bhattacharjee, A.; Germaschewski, K.

    2012-05-15

    Recently, novel experiments on magnetic reconnection have been conducted in laser-produced plasmas in a high-energy-density regime. Individual plasma bubbles self-generate toroidal, mega-gauss-scale magnetic fields through the Biermann battery effect. When multiple bubbles are created at small separation, they expand into one another, driving reconnection of this field. Reconnection in the experiments was reported to be much faster than allowed by both Sweet-Parker, and even Hall-MHD theories, when normalized to the nominal magnetic fields self-generated by single bubbles. Through particle-in-cell simulations (both with and without a binary collision operator), we model the bubble interaction at parameters and geometry relevant to the experiments. This paper discusses in detail the reconnection regime of the laser-driven experiments and reports the qualitative features of simulations. We find substantial flux-pileup effects, which boost the relevant magnetic field for reconnection in the current sheet. When this is accounted for, the normalized reconnection rates are much more in line with standard two-fluid theory of reconnection. At the largest system sizes, we additionally find that the current sheet is prone to breakup into plasmoids.

  11. Macroscale modeling and mesoscale observations of plasma density structures in the polar cap

    SciTech Connect (OSTI)

    Basu, S.; Basu, S.; Sojka, J.J.; Schunk, R.W.; MacKenzie, E.

    1995-04-15

    The seasonal and UT variation of mesoscale structures (10 km - 100 m) in the central polar cap has been obtained from an analysis of 250-MHz intensity scintillation observations made at Thule, Greenland. It has been established earlier that mesoscale structures causing scintillations of satellite signals may develop at the edges of macroscale structures (several hundred km) such as discrete polar cap plasma density enhancements or patches through the gradient drift instability process. As such, the authrs examined the seasonal and UT variation of polar cap patches simulated by using the USU Time Dependent Ionospheric Model (TDIM) under conditions of southward B(sub z). A fairly remarkable similarity is found between the scintillation observations and the model predictions of patch occurrence. For instance, both the patch and scintillation occurrences are minimized during the winter solstice (northern hemisphere) between 0800-1200 UT while also having their largest seasonal intensity between 2000-2400 UT. Little UT dependence of patches and scintillations is seen at equinox with high intensity being observed throughout the day, while during local summer the intensity of macroscale patches and mesoscale irregularities are found to be a minimum at all UT. These results indicate that macroscale features in the polar cap are routinely associated with plasma instabilities giving rise to smaller scale structures and that the specific patch formation mechanism assumed in the simulation is consistent with the observations.

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

    E-Print Network [OSTI]

    Raja, Laxminarayan L.

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

  13. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 42, NO. 10, OCTOBER 2014 3245 Development of a Gas-Fed Plasma Source for

    E-Print Network [OSTI]

    Tas, A. Cuneyt

    . Silicon and sapphire samples were exposed to the arc plasma and revealed deposition of electrode and wall plasmas are thermal arcs characterized by very high in-bore pressures (1­10 MPa) with very high inputIEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 42, NO. 10, OCTOBER 2014 3245 Development of a Gas

  14. INSTITUTE OF PHYSICS PUBLISHING PLASMA SOURCES SCIENCE AND TECHNOLOGY Plasma Sources Sci. Technol. 12 (2003) 295301 PII: S0963-0252(03)62133-X

    E-Print Network [OSTI]

    2003-01-01

    INSTITUTE OF PHYSICS PUBLISHING PLASMA SOURCES SCIENCE AND TECHNOLOGY Plasma Sources Sci. Technol. 12 (2003) 295­301 PII: S0963-0252(03)62133-X Plasma structure in a pulsed discharge environment J-6, Moffett Field, CA 94035-1000, USA E-mail: fsalama@mail.arc.nasa.gov Received 4 April 2003 Published 6 May

  15. Interchange modes in a collisional plasma Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge,

    E-Print Network [OSTI]

    , such as a levitated dipole, pro- vide a promising new approach for the magnetic confinement of plasmas for controlled- dimensional systems . This comes about as a result of an assumed simple form for the plasma equation of state

  16. Interaction of a shear Alfven wave with a filamentary density perturbation in a low-plasma

    E-Print Network [OSTI]

    Carter, Troy

    of contemporary plasma research including magnetic reconnection studies,1 formation of au- roral beams,2 solar

  17. Potential Materials Science Benefits from a Burning Plasma

    E-Print Network [OSTI]

    ­This also helps to build support for fusion energy within the broad materials science community Topic and Compatibility Phenomena Fabrication and Joining Science Materials for Attractive Fusion Energy · Structural energy sciences (build knowledge base on key feasibility issues) ·Provide excellence in materials science

  18. MIT Plasma Science & Fusion Center: research, alcator, publications...

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

    5th Annual Meeting of the APS Division of Plasma Physics, Denver, CO - 2013 Alcator Introduction Facility Information Tokamak Data & Real-Time Information Computer & Data Systems...

  19. MIT Plasma Science & Fusion Center: research, alcator, publications...

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

    6th Annual Meeting of the APS Division of Plasma Physics, new orleans, la - 2014 Alcator Introduction Facility Information Tokamak Data & Real-Time Information Computer & Data...

  20. MIT Plasma Science & Fusion Center: research, alcator, publications...

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

    4th Annual Meeting of the APS Division of Plasma Physics, Providence, RI - 2012 Alcator Introduction Facility Information Tokamak Data & Real-Time Information Computer & Data...

  1. MIT Plasma Science & Fusion Center: research>alcator>publications...

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

    Technology & Engineering Useful Links Presentations from the 46th Annual Meeting of the APS Division of Plasma Physics, Savannah, 2004 Invited Orals P. Bonoli Full-wave...

  2. Effect of shockwave-induced density jump on laser plasma interactions in low-pressure ambient air

    E-Print Network [OSTI]

    Tillack, Mark

    and Aerospace Engineering and the Center for Energy Research, University of California San Diego, 9500 Gilman significantly reduce laser energy absorbed in the solid plasma. The ionization of the density jump was confirmed , extreme ultraviolet lithography (EUVL) source 3 , and inertial fusion energy (IFE) 4 . During

  3. Macroscale modeling and mesoscale observations of plasma density structures in the polar cap

    SciTech Connect (OSTI)

    Basu, S. [Phillips Lab., Hanscom Air Force Base, MA (United States)] [Phillips Lab., Hanscom Air Force Base, MA (United States); Basu, S. [National Science Foundation, Arlington, VA (United States)] [National Science Foundation, Arlington, VA (United States); Sojka, J.J. [Utah State Univ., Logan, UT (United States)] [and others] [Utah State Univ., Logan, UT (United States); and others

    1995-04-15

    The seasonal and UT variation of mesoscale structures (10 km - 100 m) in the central polar cap has been obtained from an analysis of 250-MHz intensity scintillation observations made at Thule, Greenland. It has been established earlier that mesoscale structures causing scintillations of satellite signals may develop at the edges of macroscale structures (several hundred km) such as discrete polar cap plasma density enhancements or patches through the gradient drift instability process. As such, the authors examined the seasonal and UT variation of polar cap patches simulated by using the USU Time Dependent Ionospheric Model (TDIM) under conditions of southward B{sub z}. A fairly remarkable similarity is found between the scintillation observations and the model predictions of patch occurrence. For instance, both the patch and scintillation occurrences are minimized during the winter solstice (northern hemisphere) between 0800-1200 UT while also having their largest seasonal intensity between 2000-2400 UT. Little UT dependence of patches and scintillations is seen at equinox with high intensity being observed throughout the day, while during local summer the intensity of macroscale patches and mesoscale irregularities are found to be a minimum at all UT. These results indicate that macroscale features in the polar cap are routinely associated with plasma instabilities giving rise to smaller scale structures and that the specific patch formation mechanism assumed in the simulation is consistent with the observations. This ability to bridge between macroscale modeling and mesoscale observations provides a natural framework for the modeling of mesoscale structures themselves. This mesoscale modeling, in turn, can be utilized in a variety of radar and communication systems applications in the polar region. 25 refs., 3 figs.

  4. Whistler wave radiation from a pulsed loop antenna located in a cylindrical duct with enhanced plasma density

    SciTech Connect (OSTI)

    Kudrin, Alexander V.; Shkokova, Natalya M.; Ferencz, Orsolya E.; Zaboronkova, Tatyana M.

    2014-11-15

    Pulsed radiation from a loop antenna located in a cylindrical duct with enhanced plasma density is studied. The radiated energy and its distribution over the spatial and frequency spectra of the excited waves are derived and analyzed as functions of the antenna and duct parameters. Numerical results referring to the case where the frequency spectrum of the antenna current is concentrated in the whistler range are reported. It is shown that under ionospheric conditions, the presence of an artificial duct with enhanced density can lead to a significant increase in the energy radiated from a pulsed loop antenna compared with the case where the same source is immersed in the surrounding uniform magnetoplasma. The results obtained can be useful in planning active ionospheric experiments with pulsed electromagnetic sources operated in the presence of artificial field-aligned plasma density irregularities that are capable of guiding whistler waves.

  5. MIT Plasma Science & Fusion Center: research, alcator, publications...

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

    Research Program Information Publications & News Meetings & Seminars Contact Information Physics Research High-Energy- Density Physics Waves & Beams Technology & Engineering...

  6. Optical Probing of CO2 Laser-Plasma Interactions at Near Critical Density

    E-Print Network [OSTI]

    Gong, Chao

    2015-01-01

    applications of compact laser-plasma accelerators. Naturep. 537-545. Boyd, T.J.M. , Laser Plasma Interaction Physicsinteraction of an intense short laser pulse with a He jet.

  7. 2110 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 37, NO. 11, NOVEMBER 2009 Low-Pressure Helicon-Plasma Discharge Initiation

    E-Print Network [OSTI]

    Scharer, John E.

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

  8. MIT Plasma Science & Fusion left: research>alctor>meetings scheduled

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

    Garching, Germany 19-21 Oct. 19 June 17 July 18 Dec registration ends: 18 Sept 57th APS Div of Plasma Physics Meeting Savannah, GA 16-20 Nov. May 2015 July May June 30 Nov...

  9. MIT Plasma Science & Fusion Center: research, alcator, publications...

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

    3rd Annual Meeting of the APS Division of Plasma Physics, Salt Lake City, 2011 Invited Orals C. Fiore Production of Internal Transport Barriers via Self-Generated Mean Flows in...

  10. MIT Plasma Science & Fusion Center: research, alcator, publications...

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

    2nd Annual Meeting of the APS Division of Plasma Physics, Chicago, 2010 Invited Orals A. Hubbard I-mode regime with an edge energy transport barrier but no particle barrier in...

  11. MIT Plasma Science & Fusion Center: research, alcator, publications...

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

    8th Annual Meeting of the APS Division of Plasma Physics, Philadelphia, 2006 Invited Orals A. Hubbard H-mode pedestal and threshold studies over an expanded operating space on...

  12. MIT Plasma Science & Fusion Center: research, alcator, publications...

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

    7th Annual Meeting of the APS Division of Plasma Physics, Denver, 2005 Invited Orals R. Granetz Gas Jet Disruption Mitigation Studies on AlcatorC-MOD J. Hughes Advances in...

  13. MIT Plasma Science & Fusion Center: research, alcator, publications...

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

    0th Annual Meeting of the APS Division of Plasma Physics, Dallas, 2008 Invited Orals E. Edlund Observation of Reversed Shear Alfvn Eigenmodes During the Sawtooth Cycle in Alcator...

  14. Enhanced relativistic self-focusing of Hermite-cosh-Gaussian laser beam in plasma under density transition

    SciTech Connect (OSTI)

    Nanda, Vikas; Kant, Niti, E-mail: nitikant@yahoo.com [Department of Physics, Lovely Professional University, Phagwara 144411, Punjab (India)] [Department of Physics, Lovely Professional University, Phagwara 144411, Punjab (India)

    2014-04-15

    Enhanced and early relativistic self-focusing of Hermite-cosh-Gaussian (HChG) beam in the plasmas under density transition has been investigated theoretically using Wentzel-Kramers-Brillouin and paraxial ray approximation for mode indices m=0,?1,?and?2. The variation of beam width parameter with normalized propagation distance for m=0,?1,?and?2 is reported, and it is observed that strong self-focusing occurs as the HChG beam propagates deeper inside the nonlinear medium as spot size shrinks due to highly dense plasmas and the results are presented graphically. A comparative study between self-focusing of HChG beam in the presence and absence of plasmas density transition is reported. The dependency of beam width parameter on the normalized propagation distance for different values of decentered parameter “b” has also been presented graphically. For m=0?and?1, strong self-focusing is reported for b=1.8, and for m=2?and?b=1.8, beam gets diffracted. The results obtained indicate the dependency of the self-focusing of the HChG beam on the selected values of decentered parameter. Moreover, proper selection of decentered parameter results strong self-focusing of HChG beam. Stronger self-focusing of laser beam is observed due to the presence of plasma density transition which might be very useful in the applications like the generation of inertial fusion energy driven by lasers, laser driven accelerators, etc.

  15. Increase in the energy density of the pinch plasma in 3D implosion of quasi-spherical wire arrays

    SciTech Connect (OSTI)

    Aleksandrov, V. V., E-mail: alexvv@triniti.ru [Troitsk Institute for Innovation and Fusion Research (Russian Federation); Gasilov, V. A. [Russian Academy of Sciences, Keldysh Institute of Applied Mathematics (Russian Federation); Grabovski, E. V.; Gritsuk, A. N., E-mail: griar@triniti.ru; Laukhin, Ya. N.; Mitrofanov, K. N.; Oleinik, G. M. [Troitsk Institute for Innovation and Fusion Research (Russian Federation); Ol’khovskaya, O. G. [Russian Academy of Sciences, Keldysh Institute of Applied Mathematics (Russian Federation); Sasorov, P. V.; Smirnov, V. P.; Frolov, I. N. [Troitsk Institute for Innovation and Fusion Research (Russian Federation); Shevel’ko, A. P. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)

    2014-12-15

    Results are presented from experimental studies of the characteristics of the soft X-ray (SXR) source formed in the implosion of quasi-spherical arrays made of tungsten wires and metalized kapron fibers. The experiments were carried out at the Angara-5-1 facility at currents of up to 3 MA. Analysis of the spatial distribution of hard X-ray emission with photon energies above 20 keV in the pinch images taken during the implosion of quasi-spherical tungsten wire arrays (QTWAs) showed that a compact quasi-spherical plasma object symmetric with respect to the array axis formed in the central region of the array. Using a diffraction grazing incidence spectrograph, spectra of SXR emission with wavelengths of 20–400 Å from the central, axial, and peripheral regions of the emission source were measured with spatial resolutions along the array radius and height in the implosion of QTWAs. It is shown that the emission spectra of the SXR sources formed under the implosion of quasi-spherical and cylindrical tungsten wire arrays at currents of up to 3 MA have a maximum in the wavelength range of 50–150 Å. It is found that, during the implosion of a QTWA with a profiled linear mass, a redistribution of energy in the emission spectrum takes place, which indicates that, during 3D implosion, the energy of longitudinal motion of the array material additionally contributes to the radiation energy. It is also found that, at close masses of the arrays and close values of the current in the range of 2.4{sup ?3} MA, the average energy density in the emission source formed during the implosion of a quasi-spherical wire array is larger by a factor of 7 than in the source formed during the implosion of a cylindrical wire array. The experimental data were compared with results of 3D simulations of plasma dynamics and radiation generation during the implosion of quasi-spherical wire arrays with a profiled mass by using the MARPLE-3D radiative magnetohydrodynamic code, developed at the Keldysh Institute of Applied Mathematics, Russian Academy of Sciences.

  16. Wall current probe: A non-invasive in situ plasma diagnostic for space and time resolved current density distribution measurement

    SciTech Connect (OSTI)

    Baude, R.; Gaboriau, F.; Hagelaar, G. J. M. [Université de Toulouse, UPS, INPT, LAPLACE (Laboratoire Plasma et Conversion d’énergie), 118 route de Narbonne, F-31062 Toulouse Cedex 9, France and CNRS, LAPLACE, F-31062, Toulouse (France)] [Université de Toulouse, UPS, INPT, LAPLACE (Laboratoire Plasma et Conversion d’énergie), 118 route de Narbonne, F-31062 Toulouse Cedex 9, France and CNRS, LAPLACE, F-31062, Toulouse (France)

    2013-08-15

    In the context of low temperature plasma research, we propose a wall current probe to determine the local charged particle fluxes flowing to the chamber walls. This non-intrusive planar probe consists of an array of electrode elements which can be individually biased and for which the current can be measured separately. We detail the probe properties and present the ability of the diagnostic to be used as a space and time resolved measurement of the ion and electron current density at the chamber walls. This diagnostic will be relevant to study the electron transport in magnetized low-pressure plasmas.

  17. Materials Science and Engineering A 445446 (2007) 186192 Plastic instabilities and dislocation densities during plastic

    E-Print Network [OSTI]

    Gubicza, Jenõ

    2007-01-01

    Materials Science and Engineering A 445­446 (2007) 186­192 Plastic instabilities and dislocation densities during plastic deformation in Al­Mg alloys Gyozo Horv´ath, Nguyen Q. Chinh, Jeno Gubicza, J 2006 Abstract Plastic deformation of Al­Mg alloys were investigated by analyzing the stress

  18. MIT Plasma Science & Fusion Center: research>alcator>introduction

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

    Contact Information Physics Research High-Energy- Density Physics Waves & Beams Fusion Technology & Engineering Francis Bitter Magnet Laboratoroy Useful Links The links...

  19. MIT Plasma Science & Fusion Center: research>alcator>publications...

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

    & News Meetings & Seminars Contact Information Physics Research High-Energy- Density Physics Waves & Beams Technology & Engineering Useful Links APS Presentations New Orleans...

  20. 2852 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 39, NO. 11, NOVEMBER 2011 Focused Shadowgraphy in the Heating Volume of a

    E-Print Network [OSTI]

    Basse, Nils Plesner

    2852 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 39, NO. 11, NOVEMBER 2011 Focused Shadowgraphy Abstract--The gas or plasma flow in the heating volume is central for the interruption performance and distribution of the hot gas in the heating volume. The results can be used for further analysis of the gas/plasma

  1. Increasing the upper-limit intensity and temperature range for thermal self-focusing of a laser beam by using plasma density ramp-up

    SciTech Connect (OSTI)

    Bokaei, B.; Niknam, A. R.

    2014-03-15

    This work is devoted to improving relativistic and ponderomotive thermal self-focusing of the intense laser beam in an underdense plasma. It is shown that the ponderomotive nonlinearity induces a saturation mechanism for thermal self-focusing. Therefore, in addition to the well-known lower-limit critical intensity, there is an upper-limit intensity for thermal self-focusing above which the laser beam starts to experience ponderomotive defocusing. It is indicated that the upper-limit intensity value is dependent on plasma and laser parameters such as the plasma electron temperature, plasma density, and laser spot size. Furthermore, the effect of the upward plasma density ramp profile on the thermal self-focusing is studied. Results show that by using the plasma density ramp-up, the upper-limit intensity increases and the self-focusing temperature range expands.

  2. NNSA's holds Stewardship Science Academic Programs Annual Review...

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

    with grants or cooperative agreements as part of the Stewardship Science Academic Alliances (SSAA) Program, the High Energy Density Laboratory Plasmas (HEDLP) Program, the...

  3. Observation of a new high-? and high-density state of a magnetospheric plasma in RT-1

    SciTech Connect (OSTI)

    Saitoh, H.; Yano, Y.; Yoshida, Z.; Nishiura, M.; Morikawa, J.; Kawazura, Y.; Nogami, T.; Yamasaki, M. [Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561 (Japan)

    2014-08-15

    A new high-? and high-density state is reported for a plasma confined in a laboratory magnetosphere. In order to expand the parameter regime of an electron cyclotron resonance heating experiment, the 8.2?GHz microwave power of the Ring Trap 1 device has been upgraded with the installation of a new waveguide system. The rated input power launched from a klystron was increased from 25 to 50?kW, which enabled the more stable formation of a hot-electron high-? plasma. The diamagnetic signal (the averaged value of four magnetic loops signals) of a plasma reached 5.2 mWb. According to a two-dimensional Grad-Shafranov analysis, the corresponding local ? value is close to 100%.

  4. Nanoscale femtosecond imaging of transient hot solid density plasmas with elemental and charge state sensitivity using resonant coherent diffraction

    E-Print Network [OSTI]

    Kluge, Thomas; Chung, H -K; Gutt, C; Huang, L G; Zacharias, M; Schramm, U; Cowan, T E

    2015-01-01

    Here we propose to exploit the low energy bandwidth, small wavelength and penetration power of ultrashort pulses from XFELs for resonant Small Angle Scattering (SAXS) on plasma structures in laser excited plasmas. Small angle scattering allows to detect nanoscale density fluctuations in forward scattering direction. Typically, the SAXS signal from laser excited plasmas is expected to be dominated by the free electron distribution. We propose that the ionic scattering signal becomes visible when the X-ray energy is in resonance with an electron transition between two bound states (Resonant coherent X-ray diffraction, RCXD). In this case the scattering cross-section dramatically increases so that the signal of X-ray scattering from ions silhouettes against the free electron scattering background which allows to measure the opacity and derived quantities with high spatial and temporal resolution, being fundamentally limited only by the X-ray wavelength and timing. Deriving quantities such as ion spatial distribu...

  5. Multichannel microwave interferometer with an antenna switching system for electron density measurement in a laboratory plasma experiment

    SciTech Connect (OSTI)

    Kawamori, Eiichirou; Lin, Yu-Hsiang [Institute of Space and Plasma Sciences, National Cheng Kung University, Tainan 70101, Taiwan (China)] [Institute of Space and Plasma Sciences, National Cheng Kung University, Tainan 70101, Taiwan (China); Mase, Atsushi [Art, Science and Technology Center for Cooperative Research, Kyushu University, Kasuga 816-8580 (Japan)] [Art, Science and Technology Center for Cooperative Research, Kyushu University, Kasuga 816-8580 (Japan); Nishida, Yasushi; Cheng, C. Z. [Institute of Space and Plasma Sciences, National Cheng Kung University, Tainan 70101, Taiwan (China) [Institute of Space and Plasma Sciences, National Cheng Kung University, Tainan 70101, Taiwan (China); Plasma and Space Science Center, National Cheng Kung University, Tainan 70101, Taiwan (China)

    2014-02-15

    This study presents a simple and powerful technique for multichannel measurements of the density profile in laboratory plasmas by microwave interferometry. This technique uses electromechanical microwave switches to temporally switch the connection between multiple receiver antennas and one phase-detection circuit. Using this method, the phase information detected at different positions is rearranged into a time series that can be acquired from a minimum number of data acquisition channels (e.g., two channels in the case of quadrature detection). Our successfully developed multichannel microwave interferometer that uses the antenna switching method was applied to measure the radial electron density profiles in a magnetized plasma experiment. The advantage of the proposed method is its compactness and scalability to multidimensional measurement systems at low cost.

  6. Determination of the respective density distributions of low-and high-density lipoprotein particles in bovine plasma

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    .006-1.210 g/ml were separated by density gradient ultracentrifugation into 25 fractions. Their respective apo-I and apo B. Gradient distributions of apo A-I (d 1.046-1.180 g/ml; max at d 1.080 g/ml) and apo B (d 1: Intestinal Lipid and Lipoprotein Metabolism (Windler E, Greten H, eds), W Zuckschwerdt Verlag, Munchen, 50

  7. INSTITUTE OF PHYSICS PUBLISHING PLASMA SOURCES SCIENCE AND TECHNOLOGY Plasma Sources Sci. Technol. 12 (2003) 302312 PII: S0963-0252(03)62087-6

    E-Print Network [OSTI]

    Economou, Demetre J.

    2003-01-01

    INSTITUTE OF PHYSICS PUBLISHING PLASMA SOURCES SCIENCE AND TECHNOLOGY Plasma Sources Sci. Technol pressures (above 20 mTorr), electrons in an ICP discharge are heated by collisional dissipation of wave energy. Power deposition in lower pressure discharges, however, involves a collisionless electron heating

  8. Simulating x-ray Thomson scattering signals from high-density, millimetre-scale plasmas at the National Ignition Facility

    SciTech Connect (OSTI)

    Chapman, D. A., E-mail: david.chapman@awe.co.uk [Plasma Physics Group, Radiation Physics Department, AWE plc, Reading RG7 4PR (United Kingdom); Centre for Fusion, Space and Astrophysics, University of Warwick, Coventry CV4 7AL (United Kingdom); Kraus, D.; Falcone, R. W. [Department of Physics, University of California, Berkeley, California 94720 (United States); Kritcher, A. L.; Bachmann, B.; Collins, G. W.; Gaffney, J. A.; Hawreliak, J. A.; Landen, O. L.; Le Pape, S.; Ma, T.; Nilsen, J.; Pak, A.; Swift, D. C.; Döppner, T. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Gericke, D. O. [Centre for Fusion, Space and Astrophysics, University of Warwick, Coventry CV4 7AL (United Kingdom); Glenzer, S. H. [SLAC National Accelerator Laboratory, Menlo Park, California 94309 (United States); Guymer, T. M. [Plasma Physics Group, Radiation Physics Department, AWE plc, Reading RG7 4PR (United Kingdom); Neumayer, P. [Gesellschaft für Schwerionenforschung, 64291 Darmstadt (Germany); Redmer, R. [Institut für Physik, Universität Rostock, 18051 Rostock (Germany); and others

    2014-08-15

    We have developed a model for analysing x-ray Thomson scattering data from high-density, millimetre-scale inhomogeneous plasmas created during ultra-high pressure implosions at the National Ignition Facility in a spherically convergent geometry. The density weighting of the scattered signal and attenuation of the incident and scattered x-rays throughout the target are included using radial profiles of the density, opacity, ionization state, and temperature provided by radiation-hydrodynamics simulations. These simulations show that the scattered signal is strongly weighted toward the bulk of the shocked plasma and the Fermi degenerate material near the ablation front. We show that the scattered signal provides a good representation of the temperature of this highly nonuniform bulk plasma and can be determined to an accuracy of ca. 15% using typical data analysis techniques with simple 0D calculations. On the other hand, the mean ionization of the carbon in the bulk is underestimated. We suggest that this discrepancy is due to the convolution of scattering profiles from different regions of the target. Subsequently, we discuss modifications to the current platform to minimise the impact of inhomogeneities, as well as opacity, and also to enable probing of conditions more strongly weighted toward the compressed core.

  9. Local density for two-dimensional one-component plasma Roland Bauerschmidt

    E-Print Network [OSTI]

    Van Den Eijnden, Eric

    , Department of Mathematics. E-mail: brt@math.harvard.edu. New York University, Courant Institute-component plasma. Given a potential V : C R {+}, the energy of a configura- tion of N changes z = (z1, . . . , z. The OCP describes a plasma of positive charges confined by the potential V . In an alternative

  10. MIT Plasma Science & Fusion Center: research, alcator, publications...

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

    Oral PDF M. Greenwald - Edge Turbulence & Transport as a Possible Cause for the Tokamak Density Limit Oral PDF A. Hubbard: ASDEX-U - C-Mod Similarity Studies Oral PDF Y....

  11. MIT Plasma Fusion Sciences Center IAP Seminar! Jan 10th, 2012!

    E-Print Network [OSTI]

    MIT Plasma Fusion Sciences Center IAP Seminar! Jan 10th, 2012! ! ! ! ! ! Otto Landen! Associate-07NA27344 Inertial Confinement Fusion Physics and Challenges*! #12;The NIF ignition experiments-degenerate fuel Spherical collapse of the shell produces a central hot spot surrounded by cold, dense main fuel

  12. A US Strategy to Explore the Science and Technology of Energy-Producing Plasmas

    E-Print Network [OSTI]

    of the JET device, the world fusion community might be able to conduct significant but limited investigations1 A US Strategy to Explore the Science and Technology of Energy-Producing Plasmas Discussion Draft September 16, 1997 Introduction Last year, the Department of Energy redirected the fusion program from

  13. Convective Cell Formation in a Z-Pinch Plasma Science and Fusion Center

    E-Print Network [OSTI]

    Convective Cell Formation in a Z-Pinch J. Kesner Plasma Science and Fusion Center Massachusetts Institute of Technology Cambridge, MA 02139 PSFC Report PSFC/JA-02-27 Abstract Closed field line confinement given by Eq. (1). These equations were then applied to a hard core z pinch which can be considered

  14. Generating end plug potentials in tandem mirror plasma confinement by heating thermal particles so as to escape low density end stoppering plasmas

    DOE Patents [OSTI]

    Baldwin, David E. (Danville, CA); Logan, B. Grant (Danville, CA)

    1981-01-01

    The invention provides a method and apparatus for raising the potential of a magnetic mirror cell by pumping charged particles of the opposite sign of the potential desired out of the mirror cell through excitation, with the pumping being done by an externally imposed field at the bounce frequency of the above charged particles. These pumped simple mirror cells then provide end stoppering for a center mirror cell for the tandem mirror plasma confinement apparatus. For the substantially complete pumping case, the end plugs of a tandem mirror can be up to two orders of magnitude lower in density for confining a given center mirror cell plasma than in the case of end plugs without pumping. As a result the decrease in recirculating power required to keep the system going, the technological state of the art required, and the capital cost are all greatly lowered.

  15. The National Ignition Facility and the Golden Age of High Energy Density Science

    SciTech Connect (OSTI)

    Moses, E

    2007-08-14

    The National Ignition Facility (NIF) is a 192-beam Nd:glass laser facility being constructed at the Lawrence Livermore National Laboratory (LLNL) to conduct research in inertial confinement fusion (ICF) and high energy density (HED) science. When completed, NIF will produce 1.8 MJ, 500 TW of ultraviolet light, making it the world's largest and highest-energy laser system. The NIF is poised to become the world's preeminent facility for conducting ICF and fusion energy research and for studying matter at extreme densities and temperatures.

  16. The National Ignition Facility and the Golden Age of High Energy Density Science

    SciTech Connect (OSTI)

    Meier, W; Moses, E I; Newton, M

    2007-09-27

    The National Ignition Facility (NIF) is a 192-beam Nd:glass laser facility being constructed at the Lawrence Livermore National Laboratory (LLNL) to conduct research in inertial confinement fusion (ICF) and high energy density (HED) science. When completed, NIF will produce 1.8 MJ, 500 TW of ultraviolet light, making it the world's largest and highest-energy laser system. The NIF is poised to become the world's preeminent facility for conducting ICF and fusion energy research and for studying matter at extreme densities and temperatures.

  17. On the toroidal current density flowing across a poloidal-magnetic-field null in an axisymmetric plasma

    SciTech Connect (OSTI)

    Rodrigues, Paulo; Bizarro, Joao P. S. [Associacao Euratom-IST, Instituto de Plasmas e Fusao Nuclear, Instituto Superior Tecnico, Universidade Tecnica de Lisboa, 1049-001 Lisboa (Portugal)

    2013-04-15

    The axisymmetry condition and two of Maxwell's equations are used to show that, in general, there are no nested magnetic surfaces around a poloidal-magnetic-field null for a sufficiently small value of the toroidal current density flowing there. Hence, the toroidal current density at the axis of a magnetic configuration with extreme shear reversal cannot continuously approach zero unless nested surfaces are first broken or particular values are assigned to boundary conditions and other plasma parameters. The threshold of the toroidal current-density at which the topology changes is shown to be set by such parameters, and some examples of the predicted topology transition are presented using analytical solutions of the Grad-Shafranov equation.

  18. Study of density fluctuations and particle transport at the edge of I-mode plasmas

    E-Print Network [OSTI]

    Dominguez, Arturo, Ph. D. Massachusetts Institute of Technology

    2012-01-01

    The wide range of plasma parameters available on Alcator C-Mod has led to the accessibility of many regimes of operation. Since its commissioning, C-Mod has accessed the Linear ohmic confinement, Saturated ohmic confinement, ...

  19. 2013 Science on Saturday Lecture Series | Princeton Plasma Physics Lab

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-InspiredAtmosphericdevicesPPONeApril 30, 2013 9:30 am -NationalPlasma

  20. COLLOQUIUM: The Promise of Urban Science | Princeton Plasma Physics Lab

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room News PublicationsAudits &BradburyMay 1, 2013, 4:15pmEnergy |Princeton PlasmaPrincetonApril

  1. Worldwide conference on plasma science coming to Princeton area | Princeton

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorkingLos Alamos verifies largest single gold crystal World's largestPlasma

  2. Heavy ion fusion science research for high energy density physics and fusion applications

    E-Print Network [OSTI]

    Logan, B.G.

    2007-01-01

    Two Filtered Cathodic Arc Plasma Sources (FCAPS) streamedand two filtered cathodic arc plasma sources (FCAPS). Theorycathodic-arc and ferroelectric plasma source performance for

  3. MH4D Development Plasma Science and Innovation Center

    E-Print Network [OSTI]

    physics development ­ Variable resistivity, ohmic heating · Benchmarking ­ Screw pinch instability ­ Za magnetic field b.c. ­ Allow non-zero Etang.; Enormal=0 ­ Allow vnormal (density floor required) · Periodic than ,i i floor - , ( ),n n i i floor = + - ; ,i i floor = Atomic Physics Development Phase I #12

  4. Multi-dimensional collective effects in high-current relativistic beams relevant to High Density Laboratory Plasmas

    SciTech Connect (OSTI)

    Shvets, Gennady

    2014-05-09

    In summary, an analytical model describing the self-pinching of a relativistic charge-neutralized electron beam undergoing the collisionless Weibel instability in an overdense plasma has been developed. The model accurately predicts the final temperature and size of the self-focused filament. It is found that the final temperature is primarily defined by the total beam’s current, while the filament’s radius is shown to be smaller than the collisionless skin depth in the plasma and primarily determined by the beam’s initial size. The model also accurately predicts the repartitioning ratio of the initial energy of the beam’s forward motion into the magnetic field energy and the kinetic energy of the surrounding plasma. The density profile of the final filament is shown to be a superposition of the standard Bennett pinch profile and a wide halo surrounding the pinch, which contains a significant fraction of the beam’s electrons. PIC simulations confirm the key assumption of the analytic theory: the collisionless merger of multiple current filaments in the course of the Weibel Instability provides the mechanism for Maxwellization of the beam’s distribution function. Deviations from the Maxwell-Boltzmann distribution are explained by incomplete thermalization of the deeply trapped and halo electrons. It is conjectured that the simple expression derived here can be used for understanding collsionless shock acceleration and magnetic field amplification in astrophysical plasmas.

  5. Impact of the pedestal plasma density on dynamics of edge localized mode crashes and energy loss scaling

    SciTech Connect (OSTI)

    Xu, X. Q.; Ma, J. F.; Li, G. Q.

    2014-12-15

    The latest BOUT++ studies show an emerging understanding of dynamics of edge localized mode (ELM) crashes and the consistent collisionality scaling of ELM energy losses with the world multi-tokamak database. A series of BOUT++ simulations are conducted to investigate the scaling characteristics of the ELM energy losses vs collisionality via a density scan. Linear results demonstrate that as the pedestal collisionality decreases, the growth rate of the peeling-ballooning modes decreases for high n but increases for low n (1?plasma and yields an increasing ELM size with decreasing collisionality after a series of micro-bursts. The pedestal plasma density plays a major role in determining the ELM energy loss through its effect on the edge bootstrap current and ion diamagnetic stabilization. The critical trend emerges as a transition (1) linearly from ballooning-dominated states at high collisionality to peeling-dominated states at low collisionality with decreasing density and (2) nonlinearly from turbulence spreading dynamics at high collisionality into avalanche-like dynamics at low collisionality.

  6. The National Ignition Facility - Applications for Inertial Fusion Energy and High Energy Density Science

    SciTech Connect (OSTI)

    Campbell, E.M.; Hogan, W.J.

    1999-08-12

    Over the past several decades, significant and steady progress has been made in the development of fusion energy and its associated technology and in the understanding of the physics of high-temperature plasmas. While the demonstration of net fusion energy (fusion energy production exceeding that required to heat and confine the plasma) remains a task for the next millennia and while challenges remain, this progress has significantly increased confidence that the ultimate goal of societally acceptable (e.g. cost, safety, environmental considerations including waste disposal) central power production can be achieved. This progress has been shared by the two principal approaches to controlled thermonuclear fusion--magnetic confinement (MFE) and inertial confinement (ICF). ICF, the focus of this article, is complementary and symbiotic to MFE. As shown, ICF invokes spherical implosion of the fuel to achieve high density, pressures, and temperatures, inertially confining the plasma for times sufficient long (t {approx} 10{sup -10} sec) that {approx} 30% of the fuel undergoes thermonuclear fusion.

  7. Science On Saturday Archive | Princeton Plasma Physics Lab

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory ofDidDevelopment Top LDRDUniversitySchedulesScience Highlights Upcoming

  8. Science on Saturday: Dealing With Iran's Nuclear Program | Princeton Plasma

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation ofAlbuquerque| StanfordOffice of Science (SC) SULI HomeInfluence C.Physics

  9. Science on Saturday: Plastic Electronics | Princeton Plasma Physics Lab

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation ofAlbuquerque| StanfordOffice of Science (SC) SULI HomeInfluence6, 2016 -

  10. Science on Saturday: Plastic Electronics | Princeton Plasma Physics Lab

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation ofAlbuquerque| StanfordOffice of Science (SC) SULI HomeInfluence6, 2016

  11. Science on Saturday: Taking the Universe's Baby Picture | Princeton Plasma

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation ofAlbuquerque| StanfordOffice of Science (SC) SULI

  12. Science on Saturday: Taking the Universe's Baby Picture | Princeton Plasma

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation ofAlbuquerque| StanfordOffice of Science (SC) SULIPhysics Lab March 12,

  13. Particle radiography of high energy density plasmas Supervisors: M. Borghesi (QUB), M. Hill (AWE plc)

    E-Print Network [OSTI]

    Paxton, Anthony T.

    of relevance to fundamental plasma physics, to schemes for energy production via thermonuclear fusion (Inertial Fusion Energy, IFE), and to laboratory-based studies of astrophysical phenomena. The extreme acceleration, and filamentation, which are of relevance to areas such as Inertial Confinement Fusion

  14. Access to a New Plasma Edge State with High Density and Pressures using Quiescent H-mode

    SciTech Connect (OSTI)

    Solomon, Wayne M.; Snyder, P. B.; Burrell, K. H.; Fenstermacher, M. E.; Garofalo, A. M.; Grierson, B. A.; Loarte, A.; McKee, G. R.; Nazikian, R; Osborne, T. H.

    2014-07-01

    A path to a new high performance regime has been discovered in tokamaks that could improve the attractiveness of a fusion reactor. Experiments on DIII-D using a quiescent H-mode edge have navigated a valley of improved edge peeling-ballooning stability that opens up with strong plasma shaping at high density, leading to a doubling of the edge pressure over standard edge localized mode (ELM)ing H-mode at these parameters. The thermal energy confinement time increases both as a result of the increased pedestal height and improvements in the core transport and reduced low-k turbulence. Calculations of the pedestal height and width as a function of density using constraints imposed by peeling-ballooning and kinetic-ballooning theory are in quantitative agreement with the measurements.

  15. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 34, NO. 3, JUNE 2006 895 Simulation of Electron Kinetics in Gas Discharges

    E-Print Network [OSTI]

    Kaganovich, Igor

    IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 34, NO. 3, JUNE 2006 895 Simulation of Electron Kinetics in Gas Discharges Vladimir I. Kolobov, Senior Member, IEEE, and Robert R. Arslanbekov Abstract--We review

  16. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 39, NO. 4, APRIL 2011 995 Effect of Secondary Electron Emission on Electron

    E-Print Network [OSTI]

    IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 39, NO. 4, APRIL 2011 995 Effect of Secondary Electron, Canada. Color versions of one or more of the figures in this paper are available online at http://ieeexplore.ieee

  17. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 35, NO. 5, OCTOBER 2007 1397 Analytical Model of Heterogeneous Atomic

    E-Print Network [OSTI]

    Guerra, Vasco

    IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 35, NO. 5, OCTOBER 2007 1397 Analytical Model or more of the figures in this paper are available online at http://ieeexplore.ieee.org. Digital Object

  18. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 29, NO. 6, DECEMBER 2001 911 A Time-Domain Circuit Simulator for

    E-Print Network [OSTI]

    Lee, Hae June

    IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 29, NO. 6, DECEMBER 2001 911 A Time-Domain Circuit, and Charles K. Birdsall, Fellow, IEEE Abstract--The Curnow equivalent circuit was used to predict

  19. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 32, NO. 5, OCTOBER 2004 1843 Investigation of Plasma Evolution in a Coaxial

    E-Print Network [OSTI]

    Wirtz, Richard A.

    with a current pulse rise time of 70 ns. Two kinds of plasma objects were observed in experiments: plasma of arc of electrodes. Arc discharge typically arises near the cathode. Anode plasma arises in the later stage, after which, the plasma fills the gap. A scenario of plasma evolution of the arc discharge is discussed. Low

  20. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 40, NO. 5, MAY 2012 1265 Guest Editorial: Special Issue on Plenary and

    E-Print Network [OSTI]

    Harilal, S. S.

    IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 40, NO. 5, MAY 2012 1265 Guest Editorial: Special Issue on Plenary and Invited Papers from ICOPS 2011 THE 38th IEEE International Conference on Plasma Sci- ence. Gitomer and Assistant Publication Peer Review Support Specialist S. Gillespie of the IEEE TRANSACTIONS

  1. 190 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 30, NO. 1, FEBRUARY 2002 Gap Closure in a Cold Metal Halide Lamp

    E-Print Network [OSTI]

    Kushner, Mark

    190 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 30, NO. 1, FEBRUARY 2002 Gap Closure in a Cold Metal lamp has been investigated using a two-dimensional, plasma transport model. Im- ages are presented are found to be important during gap closure. Index Terms--Arc discharges, avalanche breakdown, glow dis

  2. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 37, NO. 12, DECEMBER 2009 2303 Nitric Oxide Formation in a Premixed Flame With

    E-Print Network [OSTI]

    Lee, Tonghun

    IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 37, NO. 12, DECEMBER 2009 2303 Nitric Oxide Formation in a Premixed Flame With High-Level Plasma Energy Coupling Xing Rao, Igor B. Matveev, and Tonghun Lee Abstract) in a transient-arc direct-current plasmatron igniter using premixed air/fuel mixtures. Quantitative measurements

  3. Electron density measurements of atmospheric-pressure non-thermal N{sub 2} plasma jet by Stark broadening and irradiance intensity methods

    SciTech Connect (OSTI)

    Xiao, Dezhi; Shen, Jie; Lan, Yan; Xie, Hongbing; Shu, Xingsheng; Meng, Yuedong; Li, Jiangang; Cheng, Cheng E-mail: paul.chu@cityu.edu.hk; Chu, Paul K. E-mail: paul.chu@cityu.edu.hk

    2014-05-15

    An atmospheric-pressure non-thermal plasma jet excited by high frequency alternating current using nitrogen is developed and the electron density in the active region of this plasma jet is investigated by two different methods using optical emission spectroscopy, Stark broadening, and irradiance intensity method. The irradiance intensity method shows that the average electron density is about 10{sup 20}/m{sup 3} which is slightly smaller than that by the Stark broadening method. However, the trend of the change in the electron density with input power obtained by these two methods is consistent.

  4. Topical Area MFE Title: Burning Plasma Science_____________________________________________ Description Fusion energy is released by burning light elements using nuclear reactions which consume mass and

    E-Print Network [OSTI]

    Page 1 Topical Area MFE Title: Burning Plasma Science but higher temperatures and better confinement is required. In magnetic fusion, plasmas are heated-sustained purely by its alpha particle heating. The science of burning plasmas consists of: (1) the physics

  5. Radiation from Ag high energy density Z-pinch plasmas and applications to lasing

    SciTech Connect (OSTI)

    Weller, M. E. Safronova, A. S.; Kantsyrev, V. L.; Esaulov, A. A.; Shrestha, I.; Stafford, A.; Keim, S. F.; Shlyaptseva, V. V.; Osborne, G. C.; Petkov, E. E.; Apruzese, J. P.; Giuliani, J. L.; Chuvatin, A. S.

    2014-03-15

    Silver (Ag) wire arrays were recently introduced as efficient x-ray radiators and have been shown to create L-shell plasmas that have the highest electron temperature (>1.8?keV) observed on the Zebra generator so far and upwards of 30?kJ of energy output. In this paper, results of single planar wire arrays and double planar wire arrays of Ag and mixed Ag and Al that were tested on the UNR Zebra generator are presented and compared. To further understand how L-shell Ag plasma evolves in time, a time-gated x-ray spectrometer was designed and fielded, which has a spectral range of approximately 3.5–5.0?Å. With this, L-shell Ag as well as cold L{sub ?} and L{sub ?} Ag lines was captured and analyzed along with photoconducting diode (PCD) signals (>0.8?keV). Along with PCD signals, other signals, such as filtered XRD (>0.2?keV) and Si-diodes (SiD) (>9?keV), are analyzed covering a broad range of energies from a few eV to greater than 53?keV. The observation and analysis of cold L{sub ?} and L{sub ?} lines show possible correlations with electron beams and SiD signals. Recently, an interesting issue regarding these Ag plasmas is whether lasing occurs in the Ne-like soft x-ray range, and if so, at what gains? To help answer this question, a non-local thermodynamic equilibrium (LTE) kinetic model was utilized to calculate theoretical lasing gains. It is shown that the Ag L-shell plasma conditions produced on the Zebra generator at 1.7 maximum current may be adequate to produce gains as high as 6?cm{sup ?1} for various 3p???3s transitions. Other potential lasing transitions, including higher Rydberg states, are also included in detail. The overall importance of Ag wire arrays and plasmas is discussed.

  6. List of Refereed Journal Publications 1. On the Existence of Moderate-Density-Burst Codes, Journal of Mathematical Sciences, Vol.

    E-Print Network [OSTI]

    Saidak, Filip

    List of Refereed Journal Publications 1. On the Existence of Moderate-Density-Burst Codes, Journal of Mathematical Sciences, Vol. 10, 8-12, 1975. 2. On UEP Burst Codes, Journal of Mathematical Sciences, Vol. 10, 21-27, 1975. 3. Linear Codes having a Sub-block Structure, Journal of Cybernetics, Vol. 6, 263

  7. A high-resolution imaging x-ray crystal spectrometer for high energy density plasmas

    SciTech Connect (OSTI)

    Chen, Hui E-mail: bitter@pppl.gov; Magee, E.; Nagel, S. R.; Park, J.; Schneider, M. B.; Stone, G.; Williams, G. J.; Beiersdorfer, P.; Bitter, M. E-mail: bitter@pppl.gov; Hill, K. W.; Kerr, S.

    2014-11-15

    Adapting a concept developed for magnetic confinement fusion experiments, an imaging crystal spectrometer has been designed and tested for HED plasmas. The instrument uses a spherically bent quartz [211] crystal with radius of curvature of 490.8 mm. The instrument was tested at the Titan laser at Lawrence Livermore National Laboratory by irradiating titanium slabs with laser intensities of 10{sup 19}–10{sup 20} W/cm{sup 2}. He-like and Li-like Ti lines were recorded, from which the spectrometer performance was evaluated. This spectrometer provides very high spectral resolving power (E/dE > 7000) while acquiring a one-dimensional image of the source.

  8. 2938 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 39, NO. 11, NOVEMBER 2011 Simulation of Plasma Flows in

    E-Print Network [OSTI]

    Carlos III de Madrid, Universidad

    in a magnetic nozzle and the generation of thrust. Index Terms--Magnetic nozzles, multi-fluid plasmas, plasma proposed as plasma acceleration devices in advanced propulsion systems. There is a clear anal- ogy between currents, different acceleration mechanisms, and downstream detachment. These plasma features can

  9. THERMAL ANNEALING OF ZNO FILMS USING HIGH-DENSITY PLASMA ARC LAMPS

    SciTech Connect (OSTI)

    Sabau, Adrian S; Dinwiddie, Ralph Barton; Xu, Jun; Angelini, Joseph Attilio; Harper, David C

    2011-01-01

    Nanostructured materials are rarely synthesized with appropriate phase and/or morphology. In this study, critical additional of as-synthesized nanostructured materials, such as annealing and/or activation of dopants, are addressed using infrared plasma arc lamps (PAL) over areas as large as 1,000 cm2. The broad spectral range of the PAL and the spectral variation of light absorption in nanostructured materials make the selection of processing parameters extremely difficult, posing a major technological barrier. In this study, the measurement of the surface temperature using various techniques for ZnO films on crystalline silicon wafers is discussed. An energy transport model for the simulation of rapid thermal processing using PAL is presented. The experimental and computational results show that the surface temperature cannot be measured directly and that computer simulation results are an effective tool for obtaining accurate data on processing temperatures.

  10. A Radiative Transport Model for Heating Paints using High Density Plasma Arc Lamps

    SciTech Connect (OSTI)

    Sabau, Adrian S; Duty, Chad E; Dinwiddie, Ralph Barton; Nichols, Mark; Blue, Craig A; Ott, Ronald D

    2009-01-01

    The energy distribution and ensuing temperature evolution within paint-like systems under the influence of infrared radiation was studied. Thermal radiation effects as well as those due to heat conduction were considered. A complete set of material properties was derived and discussed. Infrared measurements were conducted to obtain experimental data for the temperature in the paint film. The heat flux of the incident radiation from the plasma arc lamp was measured using a heat flux sensor with a very short response time. The comparison between the computed and experimental results for temperature show that the models that are based on spectral four-flux RTE and accurate optical properties yield accurate results for the black paint systems.

  11. Heavy ion fusion science research for high energy density physics and fusion applications*

    E-Print Network [OSTI]

    Wurtele, Jonathan

    . Two Filtered Cathodic Arc Plasma Sources (FCAPS) streamed aluminum metal plasma upstream toward, CA, 94551, USA 3 Princeton Plasma Physics Laboratory, Princeton, NJ 08543, USA 4 Gesellschaft fur and longitudinal compression of intense ion beams propagating through background plasma resulted in on-axis beam

  12. INSTITUTE OF PHYSICS PUBLISHING PLASMA SOURCES SCIENCE AND TECHNOLOGY Plasma Sources Sci. Technol. 11 (2002) 273278 PII: S0963-0252(02)35617-2

    E-Print Network [OSTI]

    Chen, Francis F.

    2002-01-01

    of semiconductors, ionospheric plasma research, ion lasers, general plasma physics experiments, and plasma thruster

  13. DEGAS 2 Neutral Transport Modeling of High Density, Low Temperature Plasmas

    E-Print Network [OSTI]

    , the resulting fluid neutral momentum balance in a slab geometry is d dx ³ mnv 2 + nT ´ = # T n dT dx - m# cx nv.24, and the charge exchange frequency, # cx = 2.93# cx n(T/m) 1/2 . With a neutral source on one end of the slab (x density # # n(x)/n(L), d# dx = - 2 4 (1-# T ) T (L) dT (x) dx # + ##cx [T (L)/m] 1/2 T (x) T (L) - # 2 # 2

  14. PLASMA PHYSICS:Turbulence and Sheared Flow --Burrell 281 (5384): 1816 --Science q My Science

    E-Print Network [OSTI]

    Lin, Zhihong

    About the Journal Home > Science Magazine > 18 September 1998 > Burrell , pp. 1816 - 1817 Article Views with reduced turbulence and transport when an additional source of free energy is applied to it. Usually heating or fueling. Although there are a few cases where neutral fluids exhibit velocity shear

  15. INSTITUTE OF PHYSICS PUBLISHING PLASMA SOURCES SCIENCE AND TECHNOLOGY Plasma Sources Sci. Technol. 10 (2001) 236249 www.iop.org/Journals/ps PII: S0963-0252(01)17082-9

    E-Print Network [OSTI]

    Chen, Francis F.

    2001-01-01

    helicon waves; the wave energy is subsequently converted to electron energy, thus raising the electronINSTITUTE OF PHYSICS PUBLISHING PLASMA SOURCES SCIENCE AND TECHNOLOGY Plasma Sources Sci. Technol-1594, USA 2 Plasma & Materials Technologies, Inc (now Trikon Technologies, Inc), 9255 Deering Avenue

  16. DIRECT RADIO PROBING AND INTERPRETATION OF THE SUN'S PLASMA DENSITY PROFILE

    SciTech Connect (OSTI)

    Cairns, I. H.; Lobzin, V. V.; Li, B.; Robinson, P. A.; Warmuth, A.; Mann, G.

    2009-12-01

    The Sun's electron number density profile n{sub e} (r) is vital for solar physics but not well measured or understood within a few solar radii R{sub S} . Here, a new technique extracts n{sub e} (r) directly from coronal type III radio bursts for 40 <= f <= 180 MHz. Unexpectedly, wind-like regions with n{sub e} propor to (r - R{sub S} ){sup -2} are quite common below 2R{sub S} , and coronal type IIIs often have closely linear 1/f - t spectra. The profile n{sub e} propor to (r - R{sub S} ){sup -2} is consistent with the radio data and simulations and is interpreted in terms of conical flow from localized sources (e.g., UV funnels) close to the photosphere. It is consistent with solar wind acceleration occurring for 2 <= r/R{sub S} <= 10.

  17. Demonstration of x-ray fluorescence imaging of a high-energy-density plasma

    SciTech Connect (OSTI)

    MacDonald, M. J., E-mail: macdonm@umich.edu; Gamboa, E. J. [Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, Ann Arbor, Michigan 48109 (United States); SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Keiter, P. A.; Fein, J. R.; Klein, S. R.; Kuranz, C. C.; LeFevre, H. J.; Manuel, M. J.-E.; Wan, W. C.; Drake, R. P. [Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, Ann Arbor, Michigan 48109 (United States); Montgomery, D. S. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Biener, M. M.; Fournier, K. B. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Streit, J. [Schafer Corporation, Livermore, California 94551 (United States)

    2014-11-15

    Experiments at the Trident Laser Facility have successfully demonstrated the use of x-ray fluorescence imaging (XRFI) to diagnose shocked carbonized resorcinol formaldehyde (CRF) foams doped with Ti. One laser beam created a shock wave in the doped foam. A second laser beam produced a flux of vanadium He-? x-rays, which in turn induced Ti K-shell fluorescence within the foam. Spectrally resolved 1D imaging of the x-ray fluorescence provided shock location and compression measurements. Additionally, experiments using a collimator demonstrated that one can probe specific regions within a target. These results show that XRFI is a capable alternative to path-integrated measurements for diagnosing hydrodynamic experiments at high energy density.

  18. Measurement of Electron Density near Plasma Grid of Large-scaled Negative Ion Source by Means of Millimeter-Wave Interferometer

    SciTech Connect (OSTI)

    Nagaoka, K.; Tokuzawa, T.; Tsumori, K.; Nakano, H.; Ito, Y.; Osakabe, M.; Ikeda, K.; Kisaki, M.; Shibuya, M.; Sato, M.; Komada, S.; Kondo, T.; Hayashi, H.; Asano, E.; Takeiri, Y.; Kaneko, O.

    2011-09-26

    A millimeter-wave interferometer with the frequency of 39 GHz ({lambda} 7.7 mm) was newly installed to a large-scaled negative ion source. The measurable line-integrated electron density (n{sub e}l) is from 2x10{sup 16} to 7x10{sup 18} m{sup -2}, where n{sub e} and l represent an electron density and the plasma length along the millimeter-wave path, respectively. Our interest in this study is behavior of negative ions and reduction of electron density in the beam extraction region near the plasma grid. The first results show the possibility of the electron density measurement by the millimeter-wave interferometer in this region. The line-averaged electron density increases proportional to the arc power under the condition without cesium seeding. The significant decrease of the electron density and significant increase of the negative ion density were observed just after the cesium seeding. The electron density measured with the interferometer agrees well with that observed with a Langmuir probe. The very high negative ion ratio of n{sub H-}/(n{sub e}+n{sub H-}) = 0.85 was achieved within 400 min. after the cesium seeding.

  19. Absolute atomic oxygen and nitrogen densities in radio-frequency driven atmospheric pressure cold plasmas: Synchrotron vacuum ultra-violet high-resolution Fourier-transform absorption measurements

    SciTech Connect (OSTI)

    Niemi, K.; O'Connell, D.; Gans, T.; Oliveira, N. de; Joyeux, D.; Nahon, L.; Booth, J. P.

    2013-07-15

    Reactive atomic species play a key role in emerging cold atmospheric pressure plasma applications, in particular, in plasma medicine. Absolute densities of atomic oxygen and atomic nitrogen were measured in a radio-frequency driven non-equilibrium plasma operated at atmospheric pressure using vacuum ultra-violet (VUV) absorption spectroscopy. The experiment was conducted on the DESIRS synchrotron beamline using a unique VUV Fourier-transform spectrometer. Measurements were carried out in plasmas operated in helium with air-like N{sub 2}/O{sub 2} (4:1) admixtures. A maximum in the O-atom concentration of (9.1 {+-} 0.7) Multiplication-Sign 10{sup 20} m{sup -3} was found at admixtures of 0.35 vol. %, while the N-atom concentration exhibits a maximum of (5.7 {+-} 0.4) Multiplication-Sign 10{sup 19} m{sup -3} at 0.1 vol. %.

  20. In-flight calibration of the Cassini-Radio and Plasma Wave Science (RPWS) antenna system for direction-finding and

    E-Print Network [OSTI]

    Gurnett, Donald A.

    In-flight calibration of the Cassini-Radio and Plasma Wave Science (RPWS) antenna system) as well as atmospheric (lightning) origin. The Radio and Plasma Wave Science (RPWS) experiment is designed to measure the full polarization and the wave vector of the incoming radio waves, allowing us to retrieve

  1. Assessment of an ORION-based experimental platform for measuring the opacity of high-temperature and high-density plasma

    SciTech Connect (OSTI)

    Beiersdorfer, P; Schneider, M; Shepherd, R

    2012-06-11

    The following provides an assessment of an experimental platform based on the ORION laser at AWE Aldermasten, England, for measuring the opacity of high-temperature and high-density LTE plasmas. The specific points addressed are (1) the range of electron density and temperature that can be achieved with short-pulse beams alone, as well as (2) by means of compression with a long-pulse beam; (3) the accuracy with which electron density, electron temperature, and absolute emissivity can be measured; (4) the use of pulse shaping to increase the sample density to above solid density; (5) the effect that target materials and target design have on maintaining spatial uniformity of the sample, and (6) the need for additional diagnostics to produce and characterize samples for decisive measurements.

  2. Galaxy bias from the DES Science Verification Data: combining galaxy density maps and weak lensing maps

    E-Print Network [OSTI]

    Chang, C; Gaztanaga, E; Amara, A; Refregier, A; Bacon, D; Becker, M R; Bonnett, C; Carretero, J; Castander, F J; Crocce, M; Fosalba, P; Giannantonio, T; Hartley, W; Jain, B; Jarvis, M; Kacprzak, T; Ross, A J; Sheldon, E; Troxel, M A; Vikram, V; Zuntz, J; Abbott, T M C; Abdalla, F B; Allam, S; Annis, J; Benoit-Levy, A; Bertin, E; Brooks, D; Buckley-Geer, E; Burke, D L; Capozzi, D; Rosell, A Carnero; Kind, M Carrasco; Cunha, C E; D'Andrea, C B; da Costa, L N; Desai, S; Diehl, H T; Dietrich, J P; Doel, P; Eifler, T F; Estrada, J; Evrard, A E; Flaugher, B; Frieman, J; Goldstein, D A; Gruen, D; Gruendl, R A; Gutierrez, G; Honscheid, K; James, D J; Kuehn, K; Kuropatkin, N; Lahav, O; Li, T S; Lima, M; Marshall, J L; Martini, P; Melchior, P; Miller, C J; Miquel, R; Mohr, J J; Nichol, R C; Nord, B; Ogando, R; Plazas, A A; Reil, K; Romer, A K; Roodman, A; Rykoff, E S; Sanchez, E; Scarpine, V; Schubnell, M; Sevilla-Noarbe, I; Smith, R C; Soares-Santos, M; Sobreira, F; Suchyta, E; Swanson, M E C; Tarle, G; Thomas, D; Walker, A R

    2016-01-01

    We measure the redshift evolution of galaxy bias from a magnitude-limited galaxy sample by combining the galaxy density maps and weak lensing shear maps for a $\\sim$116 deg$^{2}$ area of the Dark Energy Survey (DES) Science Verification data. This method was first developed in Amara et al. (2012) and later re-examined in a companion paper (Pujol et al., in prep) with rigorous simulation tests and analytical treatment of tomographic measurements. In this work we apply this method to the DES SV data and measure the galaxy bias for a magnitude-limited galaxy sample. We find the galaxy bias and 1$\\sigma$ error bars in 4 photometric redshift bins to be 1.33$\\pm$0.18 (z=0.2-0.4), 1.19$\\pm$0.23 (z=0.4-0.6), 0.99$\\pm$0.36 ( z=0.6-0.8), and 1.66$\\pm$0.56 (z=0.8-1.0). These measurements are consistent at the 1-2$\\sigma$ level with mea- surements on the same dataset using galaxy clustering and cross-correlation of galaxies with CMB lensing. In addition, our method provides the only $\\sigma_8$-independent constraint amon...

  3. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 43, NO. 1, JANUARY 2015 149 Global Stability Analysis of Azimuthal

    E-Print Network [OSTI]

    Carlos III de Madrid, Universidad

    IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 43, NO. 1, JANUARY 2015 149 Global Stability Analysis.ahedo@uc3m.es). Color versions of one or more of the figures in this paper are available online at http://ieeexplore.ieee

  4. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. PS-8, NO. 4, DECEMBER 1980 Behavior of a High Current Vacuum Arc Between

    E-Print Network [OSTI]

    Jerby, Eli

    IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. PS-8, NO. 4, DECEMBER 1980 Behavior of a High Current Vacuum Arc Between Hollow Cylindrical Electrodes in a Radial Magnetic Field RAYMOND L. BOXMAN, SENIOR on the behavior 0 54mm of a high current vacuum arc on cylindrical electrodes in a radial mag- 15mm netic field

  5. 2566 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 36, NO. 5, OCTOBER 2008 Quantitative Analysis of Gas Circuit Breaker

    E-Print Network [OSTI]

    Basse, Nils Plesner

    2566 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 36, NO. 5, OCTOBER 2008 Quantitative Analysis of Gas-circuit current interruption performance. In this paper, we study a single arc discharge both using measurements in the heating volume created by radiative ablation of the Polytetrafluoroethylene nozzles surrounding the arc

  6. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 36, NO. 5, OCTOBER 2008 2095 Permanent Magnet Helicon Source for Ion Propulsion

    E-Print Network [OSTI]

    Chen, Francis F.

    IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 36, NO. 5, OCTOBER 2008 2095 Permanent Magnet Helicon Source for Ion Propulsion Francis F. Chen, Life Fellow, IEEE Abstract--Helicon sources have been proposed by at least two groups for generating ions for space propulsion: the Helicon Dou- ble Layer Thruster (HDLT

  7. Al{sub 2}O{sub 3} multi-density layer structure as a moisture permeation barrier deposited by radio frequency remote plasma atomic layer deposition

    SciTech Connect (OSTI)

    Jung, Hyunsoo [Division of Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Samsung Display Co. Ltd., Tangjeong, Chungcheongnam-Do 336-741 (Korea, Republic of); Jeon, Heeyoung [Department of Nano-scale Semiconductor Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Choi, Hagyoung; Ham, Giyul; Shin, Seokyoon [Division of Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Jeon, Hyeongtag, E-mail: hjeon@hanyang.ac.kr [Division of Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Department of Nano-scale Semiconductor Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of)

    2014-02-21

    Al{sub 2}O{sub 3} films deposited by remote plasma atomic layer deposition have been used for thin film encapsulation of organic light emitting diode. In this study, a multi-density layer structure consisting of two Al{sub 2}O{sub 3} layers with different densities are deposited with different deposition conditions of O{sub 2} plasma reactant time. This structure improves moisture permeation barrier characteristics, as confirmed by a water vapor transmission rate (WVTR) test. The lowest WVTR of the multi-density layer structure was 4.7 × 10{sup ?5} gm{sup ?2} day{sup ?1}, which is one order of magnitude less than WVTR for the reference single-density Al{sub 2}O{sub 3} layer. This improvement is attributed to the location mismatch of paths for atmospheric gases, such as O{sub 2} and H{sub 2}O, in the film due to different densities in the layers. This mechanism is analyzed by high resolution transmission electron microscopy, elastic recoil detection, and angle resolved X-ray photoelectron spectroscopy. These results confirmed that the multi-density layer structure exhibits very good characteristics as an encapsulation layer via location mismatch of paths for H{sub 2}O and O{sub 2} between the two layers.

  8. Departures from local thermodynamic equilibrium in cutting arc plasmas derived from electron and gas density measurements using a two-wavelength quantitative Schlieren technique

    SciTech Connect (OSTI)

    Prevosto, L.; Mancinelli, B.; Artana, G.; Kelly, H.

    2011-03-15

    A two-wavelength quantitative Schlieren technique that allows inferring the electron and gas densities of axisymmetric arc plasmas without imposing any assumption regarding statistical equilibrium models is reported. This technique was applied to the study of local thermodynamic equilibrium (LTE) departures within the core of a 30 A high-energy density cutting arc. In order to derive the electron and heavy particle temperatures from the inferred density profiles, a generalized two-temperature Saha equation together with the plasma equation of state and the quasineutrality condition were employed. Factors such as arc fluctuations that influence the accuracy of the measurements and the validity of the assumptions used to derive the plasma species temperature were considered. Significant deviations from chemical equilibrium as well as kinetic equilibrium were found at elevated electron temperatures and gas densities toward the arc core edge. An electron temperature profile nearly constant through the arc core with a value of about 14000-15000 K, well decoupled from the heavy particle temperature of about 1500 K at the arc core edge, was inferred.

  9. The National Ignition Facility: The Path to Ignition, High Energy Density Science and Inertial Fusion Energy

    SciTech Connect (OSTI)

    Moses, E

    2011-03-25

    The National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory (LLNL) in Livermore, CA, is a Nd:Glass laser facility capable of producing 1.8 MJ and 500 TW of ultraviolet light. This world's most energetic laser system is now operational with the goals of achieving thermonuclear burn in the laboratory and exploring the behavior of matter at extreme temperatures and energy densities. By concentrating the energy from its 192 extremely energetic laser beams into a mm{sup 3}-sized target, NIF can produce temperatures above 100 million K, densities of 1,000 g/cm{sup 3}, and pressures 100 billion times atmospheric pressure - conditions that have never been created in a laboratory and emulate those in the interiors of planetary and stellar environments. On September 29, 2010, NIF performed the first integrated ignition experiment which demonstrated the successful coordination of the laser, the cryogenic target system, the array of diagnostics and the infrastructure required for ignition. Many more experiments have been completed since. In light of this strong progress, the U.S. and the international communities are examining the implication of achieving ignition on NIF for inertial fusion energy (IFE). A laser-based IFE power plant will require a repetition rate of 10-20 Hz and a 10% electrical-optical efficiency laser, as well as further advances in large-scale target fabrication, target injection and tracking, and other supporting technologies. These capabilities could lead to a prototype IFE demonstration plant in 10- to 15-years. LLNL, in partnership with other institutions, is developing a Laser Inertial Fusion Energy (LIFE) baseline design and examining various technology choices for LIFE power plant This paper will describe the unprecedented experimental capabilities of the NIF, the results achieved so far on the path toward ignition, the start of fundamental science experiments and plans to transition NIF to an international user facility providing access to researchers around the world. The paper will conclude with a discussion of LIFE, its development path and potential to enable a carbon-free clean energy future.

  10. Chiral magnetic wave at finite baryon density and the electric quadrupole moment of quark-gluon plasma in heavy ion collisions

    E-Print Network [OSTI]

    Yannis Burnier; Dmitri E. Kharzeev; Jinfeng Liao; Ho-Ung Yee

    2011-03-07

    Chiral Magnetic Wave (CMW) is a gapless collective excitation of quark-gluon plasma in the presence of external magnetic field that stems from the interplay of Chiral Magnetic (CME) and Chiral Separation Effects (CSE); it is composed by the waves of the electric and chiral charge densities coupled by the axial anomaly. We consider CMW at finite baryon density and find that it induces the electric quadrupole moment of the quark-gluon plasma produced in heavy ion collisions: the "poles" of the produced fireball (pointing outside of the reaction plane) acquire additional positive electric charge, and the "equator" acquires additional negative charge. We point out that this electric quadrupole deformation lifts the degeneracy between the elliptic flows of positive and negative pions leading to $v_2(\\pi^+) < v_2(\\pi^-)$, and estimate the magnitude of the effect.

  11. Relativistic self-focusing of ultra-high intensity X-ray laser beams in warm quantum plasma with upward density profile

    SciTech Connect (OSTI)

    Habibi, M.; Ghamari, F.

    2014-05-15

    The results of a numerical study of high-intensity X-ray laser beam interaction with warm quantum plasma (WQP) are presented. By means of an upward ramp density profile combined with quantum factors specially the Fermi velocity, we have demonstrated significant relativistic self-focusing (RSF) of a Gaussian electromagnetic beam in the WQP where the Fermi temperature term in the dielectric function is important. For this purpose, we have considered the quantum hydrodynamics model that modifies refractive index of inhomogeneous WQPs with the inclusion of quantum correction through the quantum statistical and diffraction effects in the relativistic regime. Also, to better illustration of the physical difference between warm and cold quantum plasmas and their effect on the RSF, we have derived the envelope equation governing the spot size of X-ray laser beam in Q-plasmas. In addition to the upward ramp density profile, we have found that the quantum effects would be caused much higher oscillation and better focusing of X-ray laser beam in the WQP compared to that of cold quantum case. Our computational results reveal the importance of the use of electrons density profile and Fermi speed in enhancing self-focusing of laser beam.

  12. Space and time resolved spectroscopy of laser-produced plasmas: A study of density-sensitive x-ray transitions in helium-like and neon-like ions

    SciTech Connect (OSTI)

    Young, Bruce Kai Fong

    1988-09-01

    The determination of level populations and detailed population mechanisms in dense plasmas has become an increasingly important problem in atomic physics. In this work, the density variation of line intensities and level populations in aluminum K-shell and molybdenum and silver L-shell emission spectra have been measured from high-powered, laser-produced plasmas. For each case, the density dependence of the observed line emission is due to the effect of high frequency electron-ion collisions on metastable levels. The density dependent line intensities vary greatly in laser-produced plasmas and can be used to extract detailed information concerning the population kinetics and level populations of the ions. The laser-plasmas had to be fully characterized in order to clearly compare the observed density dependence with atomic theory predictions. This has been achieved through the combined use of new diagnostic instruments and microdot targets which provided simultaneously space, time, and spectrally resolved data. The plasma temperatures were determined from the slope of the hydrogen-like recombination continuum. The time resolved electron density profiles were measured using multiple frame holographic interferometry. Thus, the density dependence of K-shell spectral lines could be clearly examined, independent of assumptions concerning the dynamics of the plasma. In aluminum, the electron density dependence of various helium-like line intensity ratios were measured. Standard collisional radiative equilibrium models fail to account for the observed density dependence measured for the ''He/sub ..cap alpha..//IC'' ratio. Instead, a quasi-steady state atomic model based on a purely recombining plasma is shown to accurately predict the measured density dependence. This same recombining plasma calculation successfully models the density dependence of the high-n ''He/sub ..gamma..//He/sub ..beta../'' and ''He/sub delta//He/sub ..beta../'' helium-like resonance line intensity ratios.

  13. Axisymmetric, High-, Steady-State Plasma Torus: A "Wind Tunnel" to Develop Whole Device Models

    E-Print Network [OSTI]

    Mauel, Michael E.

    on Integrated Simulations for Magnetic Fusion Energy Sciences: Community Teleconference Presentation CD modes; no density limits; ...) · Axisymmetry (simplicity; omnigenous drifts;...) · Simple kinetics Fusion-Relevant Plasma Torus: Axisymmetric, Levitated Current Ring Fusion Relevant Physics: Particle

  14. 2048 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 30, NO. 5, OCTOBER 2002 Plasma Molding Over Surface Topography

    E-Print Network [OSTI]

    Economou, Demetre J.

    Topography: Simulation of Ion Flow, and Energy and Angular Distributions Over Steps in RF High model was developed to study plasma "molding" over surface topography. The radio frequency (RF) sheath topography. The intermediate case is shown as L H [case (ii)]. the ion flux, IED, and ion angular

  15. 474 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 33, NO. 2, APRIL 2005 Fast Photography of a Laser Generated Plasma

    E-Print Network [OSTI]

    Najmabadi, Farrokh

    of the plasma thermal energy into kinetic energy, plume confinement, ion acceleration, emission enhancement for Energy Research, the University of California at San Diego, La Jolla, CA 92093-0438 USA (e-mail: shar of the intensifier was set at 20 ns. Ablation of carbon into a vacuum creates an intensely luminous plume

  16. 1202 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 36, NO. 4, AUGUST 2008 Controlling the Plasma Potential Distribution in

    E-Print Network [OSTI]

    --Hall discharge, plasma propulsion. I. INTRODUCTION THE HALL thruster (HT) [1] is an electromagnetic- propulsion along the magnetic-field lines (E = -ve × B) accelerates ions and gen- erates thrust. Ions HTs, the electric-field distribution is con- trolled mainly by the magnetic-field distribution

  17. 1998 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 36, NO. 5, OCTOBER 2008 Controlling the Plasma Flow in the

    E-Print Network [OSTI]

    Terms--Cross-field discharge, Langmuir probe, magnetic mirror, plasma thruster. NOMENCLATURE B Magnetic efficiency. c Electron gyrofrequency. I. INTRODUCTION THE HALL thruster [1] is a mature electric propulsion://ieeexplore.ieee.org. Digital Object Identifier 10.1109/TPS.2008.2002148 Fig. 1. Schematic of a CHT. Superimposed magnetic

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

    E-Print Network [OSTI]

    Lee, Tonghun

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

  19. Scaling of Microcavity Plasmas Toward 1 µm: Science and Engineering of Spatially-Confined, Low Temperature Plasmas

    SciTech Connect (OSTI)

    Eden, J G

    2012-03-07

    The DOE has provided, by means of the American Recovery and Reinvestment Act (ARRA), $146,400 in funding for the purchase of scientific equipment. Specifically, these funds have enabled the purchase of two scientific cameras that have already been applied to the research in microcavity plasmas at the University of Illinois (Urbana). The first camera system that was purchased with these funds is a gated ICCD system that allows events as short as 5 ns in time to be captured. It is difficult to express the impact that this equipment has already had on our research. Despite having arrived just 6 - 7 months ago, this camera system has already been used by five graduate students and several undergraduates to capture phenomena that we simply could not see in the past. As an example, the low temperature plasma confined to a spiral structure we fabricate in the Al/Al?O? materials system appears, on long time scales such as those we see with our eyes, to be spatially uniform. However, when captured with the new camera system, the plasma actually is formed initially at the center of the spiral and then moves radially (literally, "jumping" over channels as it goes) at a velocity of a few km/sec. This is an exciting result and I should add that the camera shows that plasma standing waves are produced in some of the structures as well. We do not currently understand all of the phenomena we are witnessing but it is obvious that this new system has quite literally opened new areas of plasma research and application. The second system purchased under this ARRA grant is an infrared system that is far more sensitive than anything our laboratory (or the University of Illinois, for that matter) has had previously. Although fewer experiments have been completed to date with this second camera, it is already clear that it is, indeed, extremely sensitive and it is slated for several experiments in the near future in which we will be measuring the infrared spectra of several arrays of microcavity plasmas. In summary, let me express my thanks to the DOE for granting these funds. We are most grateful for the extraordinary scientific capability that thee funds provide our students. We expect that the scientific data already acquired by this equipment will result in several publications in the next 2 - 3 months (two are being written now). Furthermore, the ability we now have to watch plasmas evolve on the nanosecond time scale has given us several ideas that are likely to result in patent applications. On behalf of our students and myself, I thank the DOE for this exceptional equipment.

  20. Generation of very low energy-spread electron beams using low-intensity laser pulses in a low-density plasma

    SciTech Connect (OSTI)

    Upadhyay, Ajay K.; Samant, Sushil Arun; Sarkar, Deepangkar; Krishnagopal, Srinivas; Jha, Pallavi

    2011-03-15

    The possibility of obtaining high-energy electron beams of high quality by using a low-density homogeneous plasma and a low-intensity laser (just above the self-injection threshold in the bubble regime) has been explored. Three-dimensional simulations are used to demonstrate, for the first time, an energy-spread of less than 1%, from self-trapping. More specifically, for a plasma density of 2x10{sup 18} cm{sup -3} and a laser intensity of a{sub 0}=2, a high-energy (0.55 GeV), ultrashort (1.4 fs) electron beam with very low energy-spread (0.55%) and high current (3 kA) is obtained. These parameters satisfy the requirements for drivers of short-wavelength free-electron lasers. It is also found that the quality of the electron beam depends strongly on the plasma length, which therefore needs to be optimized carefully to get the best performance in the experiments.

  1. Time and space resolved measurement of the electron temperature, mass density and ionization state in the ablation plasma between two exploding Al wires

    SciTech Connect (OSTI)

    Knapp, P. F.; Pikuz, S. A.; Shelkovenko, T. A.; Hammer, D. A.; Hansen, S. B.

    2012-05-15

    We have determined the properties of plasma around and between two exploding wires using high-resolution x-ray absorption spectroscopy. Plasma densities and temperatures ranging from Greater-Than-Or-Equivalent-To 0.1g/cm{sup 3} and a few eV to less than 0.01 g/cm{sup 3} and 30 eV have been measured in experiments at Cornell University with two 40 {mu}m aluminum (Al) wires spaced 1 mm apart driven by {approx}150 kA peak current pulses with 100 ns rise time. The wire plasma was backlit by the 1.4-1.6 keV continuum radiation produced by a Mo wire X-pinch. The spectrometer employed two spherically bent quartz crystals to record the absorption and backlighter spectra simultaneously. The transition between the dense Al wire core and the coronal plasma is seen as a transition from cold K-edge absorption to Mg-, Na-, and finally Ne-like absorption at the boundary. In the plasma that accumulates between the wires, ionization states up to C-Like Al are observed. The spectrometer geometry and {approx}2{mu}m X-pinch source size provide 0.3 eV spectral resolution and 20 {mu}m spatial resolution enabling us to see 1s{yields} 2p satellite transitions as separate lines as well as O-, F-, and Ne-like 1s{yields} 3p transitions that have not been seen before. A step wedge was used to calibrate the transmission, enabling density to be measured within a factor of two and temperature to be measured within {+-}25%. A genetic algorithm was developed to fit synthetic spectra calculated using the collisional-radiative code SCRAM to the experimental spectra. In order to obtain agreement it was necessary to assume multiple plasma regions with variable thicknesses, thereby allowing the inferred plasma conditions to vary along the absorption path.

  2. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 34, NO. 4, AUGUST 2006 1105 A Study of ZrN/Zr Coatings Deposited on

    E-Print Network [OSTI]

    Zheng, Yufeng

    IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 34, NO. 4, AUGUST 2006 1105 A Study of ZrN/Zr Coatings/metal coatings were deposited onto NiTi shape-memory alloy using plasma immersion ion im- plantation, such as unbalanced magnetron sputtering, ion plat- ing, ion-beam-assisted deposition, cathodic-vacuum-arc evapo

  3. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 42, NO. 6, JUNE 2014 1531 Effects of a Conducting Wall on Z-Pinch Stability

    E-Print Network [OSTI]

    IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 42, NO. 6, JUNE 2014 1531 Effects of a Conducting Wall for these investigations. Plasma conditions with various pinch sizes were studied numerically to better understand confinement configurations. Early experimental work with arc sources in high-temperature gases found a close

  4. 714 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 38, NO. 4, APRIL 2010 Interaction of a CO2 Laser Pulse With Tin-Based

    E-Print Network [OSTI]

    Najmabadi, Farrokh

    714 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 38, NO. 4, APRIL 2010 Interaction of a CO2 Laser--The interaction of a CO2 laser pulse with Sn-based plasma for a 13.5-nm extreme ultraviolet (EUV) lithography source was investigated. It was noted that a CO2 laser with wavelength of 10.6 m is more sensitive

  5. Diagnosing collisions of magnetized, high energy density plasma flows using a combination of collective Thomson scattering, Faraday rotation, and interferometry (invited)

    SciTech Connect (OSTI)

    Swadling, G. F., E-mail: swadling@imperial.ac.uk; Lebedev, S. V.; Hall, G. N.; Patankar, S.; Stewart, N. H.; Smith, R. A.; Burdiak, G. C.; Grouchy, P. de; Skidmore, J.; Suttle, L.; Suzuki-Vidal, F.; Bland, S. N.; Kwek, K. H.; Pickworth, L.; Bennett, M.; Hare, J. D. [Plasma Physics Group, Imperial College, London SW6 7LZ (United Kingdom); Harvey-Thompson, A. J. [Sandia National Laboratory, Albuquerque, New Mexico 87185-1193 (United States); Rozmus, W. [Department of Physics, University of Alberta, Edmonton, Alberta T6G 2J1 (Canada); Yuan, J. [Key Laboratory of Pulsed Power, Institute of Fluid Physics, CAE, Mianyang 621900 (China)

    2014-11-15

    A suite of laser based diagnostics is used to study interactions of magnetised, supersonic, radiatively cooled plasma flows produced using the Magpie pulse power generator (1.4 MA, 240 ns rise time). Collective optical Thomson scattering measures the time-resolved local flow velocity and temperature across 7–14 spatial positions. The scattering spectrum is recorded from multiple directions, allowing more accurate reconstruction of the flow velocity vectors. The areal electron density is measured using 2D interferometry; optimisation and analysis are discussed. The Faraday rotation diagnostic, operating at 1053 nm, measures the magnetic field distribution in the plasma. Measurements obtained simultaneously by these diagnostics are used to constrain analysis, increasing the accuracy of interpretation.

  6. Large Scale Computing and Storage Requirements for Fusion Energy Sciences Research

    E-Print Network [OSTI]

    Gerber, Richard

    2012-01-01

    basic plasma science, including both burning plasma and low temperature plasma science and engineering, to enhance economic

  7. Moiré deflectometry using the Talbot-Lau interferometer as refraction diagnostic for High Energy Density plasmas at energies below 10 keV

    SciTech Connect (OSTI)

    Valdivia, M. P.; Stutman, D.; Finkenthal, M.

    2014-07-15

    The highly localized density gradients expected in High Energy Density (HED) plasma experiments can be characterized by x-ray phase-contrast imaging in addition to conventional attenuation radiography. Moiré deflectometry using the Talbot-Lau grating interferometer setup is an attractive HED diagnostic due to its high sensitivity to refraction induced phase shifts. We report on the adaptation of such a system for operation in the sub-10 keV range by using a combination of free standing and ultrathin Talbot gratings. This new x-ray energy explored matches well the current x-ray backlighters used for HED experiments, while also enhancing phase effects at lower electron densities. We studied the performance of the high magnification, low energy Talbot-Lau interferometer, for single image phase retrieval using Moiré fringe deflectometry. Our laboratory and simulation studies indicate that such a device is able to retrieve object electron densities from phase shift measurements. Using laboratory x-ray sources from 7 to 15 ?m size we obtained accurate simultaneous measurements of refraction and attenuation for both sharp and mild electron density gradients.

  8. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. PS-14, NO. 2, APRIL 1986 Effect of Silane Pressure on Silane-Hydrogen RF

    E-Print Network [OSTI]

    Kushner, Mark

    . J. Kampas was supported by the Office of Basic Energy Sciences, Division of Materials Science of the U.S. Department of Energy. The work of M. J. Kushner was supported by Spectra Technology, Inc. F. J in a manner consistent with a similar decrease in average electron energy. Results from a Monte Carlo plasma

  9. Plasma Wakefield Acceleration and FACET - Facilities for Accelerator Science and Experimental Test Beams at SLAC

    ScienceCinema (OSTI)

    Andrei Seryi

    2010-01-08

    Plasma wakefield acceleration is one of the most promising approaches to advancing accelerator technology. This approach offers a potential 1,000-fold or more increase in acceleration over a given distance, compared to existing accelerators.  FACET, enabled by the Recovery Act funds, will study plasma acceleration, using short, intense pulses of electrons and positrons. In this lecture, the physics of plasma acceleration and features of FACET will be presented.  

  10. U.S. Department of Energy's Plasma Science Center holds third...

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

    on nanoparticles in dusty plasmas. Meeting participants viewed components of the National Compact Stellarator Experiment during a tour of PPPL. (Photo by Elle Starkman, PPPL Office...

  11. Estimation of the electron density and radiative energy losses in a calcium plasma source based on an electron cyclotron resonance discharge

    SciTech Connect (OSTI)

    Potanin, E. P. Ustinov, A. L.

    2013-06-15

    The parameters of a calcium plasma source based on an electron cyclotron resonance (ECR) discharge were calculated. The analysis was performed as applied to an ion cyclotron resonance system designed for separation of calcium isotopes. The plasma electrons in the source were heated by gyrotron microwave radiation in the zone of the inhomogeneous magnetic field. It was assumed that, in such a combined trap, the energy of the extraordinary microwave propagating from the high-field side was initially transferred to a small group of resonance electrons. As a result, two electron components with different transverse temperatures-the hot resonance component and the cold nonresonance component-were created in the plasma. The longitudinal temperatures of both components were assumed to be equal. The entire discharge space was divided into a narrow ECR zone, where resonance electrons acquired transverse energy, and the region of the discharge itself, where the gas was ionized. The transverse energy of resonance electrons was calculated by solving the equations for electron motion in an inhomogeneous magnetic field. Using the law of energy conservation and the balance condition for the number of hot electrons entering the discharge zone and cooled due to ionization and elastic collisions, the density of hot electrons was estimated and the dependence of the longitudinal temperature T{sub e Parallel-To} of the main (cold) electron component on the energy fraction {beta} lost for radiation was obtained.

  12. Direct asymmetry measurement of temperature and density spatial distributions in inertial confinement fusion plasmas from pinhole space-resolved spectra

    E-Print Network [OSTI]

    Nagayama, T; Florido, R; Mayes, D; Tommasini, R; Koch, J A; Delettrez, J A; Regan, S P; Smalyuk, V A

    2014-01-01

    Two-dimensional space-resolved temperature and density images of an inertial confinement fusion (ICF) implosion core have been diagnosed for the first time. Argon-doped, direct-drive ICF experiments were performed at the Omega Laser Facility and a collection of two-dimensional space-resolved spectra were obtained from an array of gated, spectrally resolved pinhole images recorded by a multi-monochromatic x-ray imager. Detailed spectral analysis revealed asymmetries of the core not just in shape and size but in the temperature and density spatial distributions, thus characterizing the core with an unprecedented level of detail.

  13. Direct asymmetry measurement of temperature and density spatial distributions in inertial confinement fusion plasmas from pinhole space-resolved spectra

    SciTech Connect (OSTI)

    Nagayama, T.; Mancini, R. C.; Florido, R.; Mayes, D. [Physics Department, University of Nevada, Reno, Nevada 89557 (United States)] [Physics Department, University of Nevada, Reno, Nevada 89557 (United States); Tommasini, R.; Koch, J. A. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)] [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Delettrez, J. A.; Regan, S. P.; Smalyuk, V. A. [Laboratory for Laser Energetics, University of Rochester, New York 14623 (United States)] [Laboratory for Laser Energetics, University of Rochester, New York 14623 (United States)

    2014-05-15

    Two-dimensional space-resolved temperature and density images of an inertial confinement fusion (ICF) implosion core have been diagnosed for the first time. Argon-doped, direct-drive ICF experiments were performed at the Omega Laser Facility and a collection of two-dimensional space-resolved spectra were obtained from an array of gated, spectrally resolved pinhole images recorded by a multi-monochromatic x-ray imager. Detailed spectral analysis revealed asymmetries of the core not just in shape and size but in the temperature and density spatial distributions, thus characterizing the core with an unprecedented level of detail.

  14. Experimental and numerical investigations on the density profile of CO2 laser-produced Sn plasma for an EUVL source

    E-Print Network [OSTI]

    Najmabadi, Farrokh

    fusion and laser fabrication, mysteries are still remaining in the fundamentals of the generation of in Research and Development Center, Kanagawa, Japan. c Electric and Computer Engineering Dept., University the critical density. This research suggests that more efforts to understand the fundamental dominating

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

    E-Print Network [OSTI]

    Gain (Qp) · Fusion Energy Density · Duty Cycle/Repetition Rate The Grand Challenge, Science compression drive (laser-D/I, beam) radial profile time profile electrostatic #12;Plasma Requirements drive Nova indirect drive Nova direct drive Laser D-T #12;Comparison of Typical Plasma Parameters

  16. Research | Princeton Plasma Physics Lab

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

    Overview Experimental Fusion Research Theoretical Fusion Research Basic Plasma Science Plasma Astrophysics Other Physics and Engineering Research PPPL Technical Reports NSTX-U...

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

    SciTech Connect (OSTI)

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

    2014-10-15

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

  18. INSTITUTE OF PHYSICS PUBLISHING PLASMA SOURCES SCIENCE AND TECHNOLOGY Plasma Sources Sci. Technol. 12 (2003) 561575 PII: S0963-0252(03)66965-3

    E-Print Network [OSTI]

    Kushner, Mark

    2003-01-01

    , Department of Nuclear Engineering, 1406 W. Green St., Urbana, IL 61801, USA 2 Plasma Research Laboratory

  19. Princeton Plasma Physics Laboratory | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorkingLosThe23-24, 2011 HighMayOctoberPrinceton PlasmaPrinceton Plasma

  20. On the program, vision, and budget for the fusion and plasma sciences

    E-Print Network [OSTI]

    relevant to clean energy with near-term payoff. With this as backdrop, the Administration affirms a strong commitment to ITER, recognizing its importance to fusion and potentially to the energy economy in the second foundations needed to develop a fusion energy source. This is accomplished by the study of the plasma state

  1. Porkolab_FPA_12.4.2008 Plasma Science and Fusion Center

    E-Print Network [OSTI]

    : Alcator C-Mod Levitated Dipole Experiment :LDX ICF/HEDP Activities Miklos Porkolab With input from Earl Marmar (C-Mod), Jay Kesner (LDX), Mike Mauel (LDX), Rich Petrasso (ICF/HEDP) Fusion Power Associates and engineering necessary for a burning plasma tokamak experiment and for attractive fusion reactors. Developing

  2. IOP PUBLISHING PLASMA SOURCES SCIENCE AND TECHNOLOGY Plasma Sources Sci. Technol. 16 (2007) 832838 doi:10.1088/0963-0252/16/4/019

    E-Print Network [OSTI]

    2007-01-01

    .iop.org/PSST/16/832 Abstract We report on investigations of gas metal arc welding plasma operated in pure argon increases while approaching the core of the plasma in the spray-arc mode, a drop in the electron temperature, a liquid, a gas and a plasma interact as an electrode, an arc, molten metal and a base metal. The welding

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

    E-Print Network [OSTI]

    Chen, Francis F.

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

  4. , 2003, 123, . 3, . 1 16 c INTERNAL ENERGY OF HIGH-DENSITY HYDROGEN

    E-Print Network [OSTI]

    Bonitz, Michael

    �Ý��, 2003, òîì 123, âûï. 3, ñòð. 1#21;16 c 2003 INTERNAL ENERGY OF HIGH-DENSITY HYDROGEN 2002 The internal energy of high-density hydrogen plasmas in the temperature range T = 10000-Universität Berlin D-10115, Berlin, Germany b Institute for High Energy Density, Russian Academy of Sciences 127412

  5. Abstract submitted for the 1979 IEEE INTERNATIONAL CONFERENCE ON PLASMA SCIENCE

    E-Print Network [OSTI]

    Sprott, Julien Clinton

    experiment is run at the 250 kW level in hydrogen with a 5% doping of helium to enable ion temperature Varennes, Quebec, Canada A.P. Biddle and J.C. Sprott COO-2387-100 #12;High Power Heating and Propagation turn loop located out side the vacuum tank which views the plasma through a 9 cm diameter 1.3 cm thick

  6. Stark broadening for diagnostics of the electron density in non-equilibrium plasma utilizing isotope hydrogen alpha lines

    SciTech Connect (OSTI)

    Yang, Lin; Tan, Xiaohua; Wan, Xiang; Chen, Lei; Jin, Dazhi; Qian, Muyang; Li, Gongping

    2014-04-28

    Two Stark broadening parameters including FWHM (full width at half maximum) and FWHA (full width at half area) of isotope hydrogen alpha lines are simultaneously introduced to determine the electron density of a pulsed vacuum arc jet. To estimate the gas temperature, the rotational temperature of the C{sub 2} Swan system is fit to 2500?±?100?K. A modified Boltzmann-plot method with b{sub i}-factor is introduced to determine the modified electron temperature. The comparison between results of atomic and ionic lines indicates the jet is in partial local thermodynamic equilibrium and the electron temperature is close to 13?000?±?400?K. Based on the computational results of Gig-Card calculation, a simple and precise interpolation algorithm for the discrete-points tables can be constructed to obtain the traditional n{sub e}-T{sub e} diagnostic maps of two Stark broadening parameters. The results from FWHA formula by the direct use of FWHM?=?FWHA and these from the diagnostic map are different. It can be attributed to the imprecise FWHA formula form and the deviation between FWHM and FWHA. The variation of the reduced mass pair due to the non-equilibrium effect contributes to the difference of the results derived from two hydrogen isotope alpha lines. Based on the Stark broadening analysis in this work, a corrected method is set up to determine n{sub e} of (1.10?±?0.08)?×?10{sup 21}?m{sup ?3}, the reference reduced mass ?{sub 0} pair of (3.30?±?0.82 and 1.65?±?0.41), and the ion kinetic temperature of 7900?±?1800?K.

  7. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 39, NO. 6, JUNE 2011 1507 Microfabricated Flexible Electrodes for Multiaxis

    E-Print Network [OSTI]

    Carter, Troy

    harder to construct reliably by hand. Devices fabricated utilizing microelectromechanical systems (MEMS, microelectromechanical systems (MEMS) devices, plasma diagnostics. I. INTRODUCTION THE ABILITY TO take plasma of laboratory plasmas (i.e., Debye length, ion gyroradius, etc.). MEMS, or microelectromechanical systems

  8. Physical Sciences 2007 Science & Technology Highlights

    SciTech Connect (OSTI)

    Hazi, A U

    2008-04-07

    The Physical Sciences Directorate applies frontier physics and technology to grand challenges in national security. Our highly integrated and multidisciplinary research program involves collaborations throughout Lawrence Livermore National Laboratory, the National Nuclear Security Administration, the Department of Energy, and with academic and industrial partners. The Directorate has a budget of approximately $150 million, and a staff of approximately 350 employees. Our scientists provide expertise in condensed matter and high-pressure physics, plasma physics, high-energy-density science, fusion energy science and technology, nuclear and particle physics, accelerator physics, radiation detection, optical science, biotechnology, and astrophysics. This document highlights the outstanding research and development activities in the Physical Sciences Directorate that made news in 2007. It also summarizes the awards and recognition received by members of the Directorate in 2007.

  9. ScienceLive chat page: on the future of fusion research | Princeton Plasma

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation ofAlbuquerque| StanfordOffice of Science (SC)Science-DrivenPhysics Lab

  10. Princeton Plasma Physics Laboratory | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorkingLosThe23-24, 2011 HighMayOctoberPrinceton Plasma Physics Laboratory

  11. Princeton Plasma Physics Laboratory | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorkingLosThe23-24, 2011 HighMayOctoberPrinceton Plasma Physics

  12. Princeton Plasma Physics Laboratory | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorkingLosThe23-24, 2011 HighMayOctoberPrinceton Plasma PhysicsPrinceton

  13. Princeton Plasma Physics Laboratory | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorkingLosThe23-24, 2011 HighMayOctoberPrinceton Plasma

  14. Princeton Plasma Physics Laboratory | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorkingLosThe23-24, 2011 HighMayOctoberPrinceton PlasmaPrinceton

  15. Princeton Plasma Physics Laboratory | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorkingLosThe 26thIWalter H.4 » InsidePacificPresidentPrinceton Plasma

  16. IOP PUBLISHING PLASMA SOURCES SCIENCE AND TECHNOLOGY Plasma Sources Sci. Technol. 21 (2012) 055003 (7pp) doi:10.1088/0963-0252/21/5/055003

    E-Print Network [OSTI]

    Harilal, S. S.

    2012-01-01

    2 1 Center for Materials Under Extreme Environment, School of Nuclear Engineering, Purdue University emission, expansion, and kinetic properties of the ejected particles from the plasma is essential

  17. Study of electron acceleration and x-ray radiation as a function of plasma density in capillary-guided laser wakefield accelerators

    SciTech Connect (OSTI)

    Ju, J.; Döpp, A.; Cros, B.; Svensson, K.; Genoud, G.; Wojda, F.; Burza, M.; Persson, A.; Lundh, O.; Wahlström, C.-G.; Ferrari, H.

    2013-08-15

    Laser wakefield electron acceleration in the blow-out regime and the associated betatron X-ray radiation were investigated experimentally as a function of the plasma density in a configuration where the laser is guided. Dielectric capillary tubes were employed to assist the laser keeping self-focused over a long distance by collecting the laser energy around its central focal spot. With a 40 fs, 16 TW pulsed laser, electron bunches with tens of pC charge were measured to be accelerated to an energy up to 300 MeV, accompanied by X-ray emission with a peak brightness of the order of 10{sup 21} ph/s/mm{sup 2}/mrad{sup 2}/0.1%BW. Electron trapping and acceleration were studied using the emitted X-ray beam distribution to map the acceleration process; the number of betatron oscillations performed by the electrons was inferred from the correlation between measured X-ray fluence and beam charge. A study of the stability of electron and X-ray generation suggests that the fluctuation of X-ray emission can be reduced by stabilizing the beam charge. The experimental results are in good agreement with 3D particle-in-cell (PIC) simulation.

  18. Laser Plasma Particle Accelerators: Large Fields for Smaller Facility Sources

    E-Print Network [OSTI]

    Geddes, Cameron G.R.

    2010-01-01

    of high- gradient, laser plasma particle accelerators.accelerators that use laser-driven plasma waves. Theseleft) showing the laser (red), plasma wake density (purple-

  19. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 21, NO. 3. JUNE 1993 27 1 Electron Cyclotron Wave Propagation,

    E-Print Network [OSTI]

    Scharer, John E.

    propagation and absorption Ehave been and continue to be an intriguing plasma physics research area. Mc

  20. Advances in compact proton spectrometers for inertial-confinement fusion and plasma nuclear science

    SciTech Connect (OSTI)

    Seguin, F. H.; Sinenian, N.; Rosenberg, M.; Zylstra, A.; Manuel, M. J.-E.; Sio, H.; Waugh, C.; Rinderknecht, H. G.; Johnson, M. Gatu; Frenje, J.; Li, C. K.; Petrasso, R. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Sangster, T. C.; Roberts, S. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623 (United States)

    2012-10-15

    Compact wedge-range-filter proton spectrometers cover proton energies {approx}3-20 MeV. They have been used at the OMEGA laser facility for more than a decade for measuring spectra of primary D{sup 3}He protons in D{sup 3}He implosions, secondary D{sup 3}He protons in DD implosions, and ablator protons in DT implosions; they are now being used also at the National Ignition Facility. The spectra are used to determine proton yields, shell areal density at shock-bang time and compression-bang time, fuel areal density, and implosion symmetry. There have been changes in fabrication and in analysis algorithms, resulting in a wider energy range, better accuracy and precision, and better robustness for survivability with indirect-drive inertial-confinement-fusion experiments.

  1. High Energy Density Microwaves

    SciTech Connect (OSTI)

    Phillips, R.M. [Stanford Linear Accelerator Center, Stanford, CA 94309 (United States)

    1999-04-01

    These proceedings represent papers presented at the RF98 Workshop entitled `High Energy Density Microwaves` held in California in October, 1998. The topics discussed were predominantly accelerator{minus}related. The Workshop dealt, for the most part, with the generation and control of electron beams, the amplification of RF signals, the design of mode converters, and the effect of very high RF field gradients. This Workshop was designed to address the concerns of the microwave tube industry worldwide, the plasma physicists who deal with very high beam currents and gigawatts of RF power, and researchers in accelerator centers around the world. Papers were presented on multibeam klystrons, gyrotron development, plasmas in microwave tubes, RF breakdown, and alternatives to conventional linear coliders at 1 TeV and above. The Workshop was partially sponsored by the US Department of Energy. There were 46 papers presented at the conference,out of which 19 have been abstracted for the Energy,Science and Technology database.(AIP)

  2. Science on Saturday: Title To Be Announced | Princeton Plasma Physics Lab

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation ofAlbuquerque| StanfordOffice of Science (SC) SULIPhysics Lab

  3. Science on Saturday: Title To Be Announced | Princeton Plasma Physics Lab

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation ofAlbuquerque| StanfordOffice of Science (SC) SULIPhysics LabFebruary

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

    SciTech Connect (OSTI)

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

    2014-01-07

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

  5. Frontiers for Discovery in High Energy Density Physics

    SciTech Connect (OSTI)

    Davidson, R. C.; Katsouleas, T.; Arons, J.; Baring, M.; Deeney, C.; Di Mauro, L.; Ditmire, T.; Falcone, R.; Hammer, D.; Hill, W.; Jacak, B.; Joshi, C.; Lamb, F.; Lee, R.; Logan, B. G.; Melissinos, A.; Meyerhofer, D.; Mori, W.; Murnane, M.; Remington, B.; Rosner, R.; Schneider, D.; Silvera, I.; Stone, J.; Wilde, B.; Zajc. W.

    2004-07-20

    The report is intended to identify the compelling research opportunities of high intellectual value in high energy density physics. The opportunities for discovery include the broad scope of this highly interdisciplinary field that spans a wide range of physics areas including plasma physics, laser and particle beam physics, nuclear physics, astrophysics, atomic and molecular physics, materials science and condensed matter physics, intense radiation-matter interaction physics, fluid dynamics, and magnetohydrodynamics

  6. Final report for the NSF/DOE partnership in basic plasma science grant DE-FG02-06ER54906 '?Laser-driven collisionless shocks in the Large Plasma Device'?

    SciTech Connect (OSTI)

    Niemann, Christoph; Gekelman, W.; Winske, D.; Larsen, D.

    2012-12-14

    We have performed several thousand high-energy laser shots in the LAPD to investigate the dynamics of an exploding laser-produced plasma in a large ambient magneto-plasma. Debris-ions expanding at super-Alfvenic velocity (up to MA=1.5) expel the ambient magnetic field, creating a large (> 20 cm) diamagnetic cavity. We observed field compressions of up to B/B{sub 0} = 1.5 at the edge of the bubble, consistent with the MHD jump conditions, as well as localized electron heating at the edge of the bubble. Two-dimensional hybrid simulations reproduce these measurements well and show that the majority of the ambient ions are energized by the magnetic piston to super-Alfvenic speeds and swept outside the bubble volume. Nonlinear shear-Alfven waves ({delta}B/B{sub 0} > 25%) are radiated from the cavity with a coupling efficiency of 70% from magnetic energy in the bubble to the wave. While the data is consistent with a weak magneto-sonic shock, the experiments were severely limited by the low ambient plasma densities (10{sup 12} cm{sup -3}). 2D hybrid simulations indicate that future experiments with the new LAPD plasma source and densities in excess of 10{sup 13} cm{sup -3} will drive full-blown collisionless shocks with MA>10 over several c/wpi and shocked Larmor radii. In a separate experiment at the LANL Trident laser facility we have performed a proof-of-principle experiment at higher densities to demonstrate key elements of collisionless shocks in laser-produced magnetized plasmas with important implications to NIF. Simultaneously we have upgraded the UCLA glass-laser system by adding two large amplitude disk amplifiers from the NOVA laser and boost the on-target energy from 30 J to up to 1 kJ, making this one of the world’s largest university-scale laser systems. We now have the infrastructure in place to perform novel and unique high-impact experiments on collision-less shocks at the LAPD.

  7. IOP PUBLISHING PLASMA SOURCES SCIENCE AND TECHNOLOGY Plasma Sources Sci. Technol. 18 (2009) 045003 (6pp) doi:10.1088/0963-0252/18/4/045003

    E-Print Network [OSTI]

    2009-01-01

    uranium is produced by the gas centrifuge method [7], a significant number of isotopes are still produced (6pp) doi:10.1088/0963-0252/18/4/045003 Wave-driven countercurrent plasma centrifuge Abraham J centrifuge is described. The rotation is produced by radiofrequency waves near the cyclotron resonance

  8. A conventional one-channel Thomson scattering (TS) system was implemented to measure the electron temperature and density profiles on the ETE tokamak plasma with a resolution of 15 mm along 50 cm inside the plasma. The TS is based on a 10 J Q-switched rub

    E-Print Network [OSTI]

    temperature and density profiles on the ETE tokamak plasma with a resolution of 15 mm along 50 cm inside.5mmx1.5mm that is spectral analyzed by a 5-channel filter polychromator. Temperatures from 20 eV to 160 uses large core monofibers (d = 0.8 mm, NA = 0.39, average attenuation: 7 dB/Km) with micro-lenses (d

  9. 1738 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 36, NO. 4, AUGUST 2008 Propagation of a Short Intense Laser Pulse

    E-Print Network [OSTI]

    Strathclyde, University of

    Intense Laser Pulse in a Curved Plasma Channel Albert Reitsma and Dino Jaroszynski Abstract--In this paper laser light. If there is a perfect balance between the inward bending of light rays through the light along a curved path by bending the waveguide. Light bending in a plasma waveguide has been

  10. Princeton Plasma Physics Laboratory

    SciTech Connect (OSTI)

    Not Available

    1990-01-01

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

  11. Intense Magnetized Plasma-Wall Interaction

    SciTech Connect (OSTI)

    Bauer, Bruno S.; Fuelling, Stephan

    2013-11-30

    This research project studied wall-plasma interactions relevant to fusion science. Such interactions are a critical aspect of Magneto-Inertial Fusion (MIF) because flux compression by a pusher material, in particular the metal for the liner approach to MIF, involves strong eddy current heating on the surface of the pusher, and probably interactions and mixing of the pusher with the interior fuel during the time when fusion fuel is being burned. When the pusher material is a metal liner, high-energy-density conditions result in fascinating behavior. For example, "warm dense matter" is produced, for which material properties such as resistivity and opacity are not well known. In this project, the transformation into plasma of metal walls subjected to pulsed megagauss magnetic fields was studied with an experiment driven by the UNR 1 MA Zebra generator. The experiment was numerically simulated with using the MHRDR code. This simple, fundamental high-energy-density physics experiment, in a regime appropriate to MIF, has stimulated an important and fascinating comparison of numerical modeling codes and tables with experiment. In addition, we participated in developing the FRCHX experiment to compress a field-reversed-configuration (FRC) plasma with a liner, in collaboration with researchers from Air Force Research Laboratory and Los Alamos National Lab, and we helped develop diagnostics for the Plasma Liner Experiment (PLX) at LANL. Last, but not least, this project served to train students in high-energy-density physics.

  12. Measurement of Charged-Particle Stopping in Warm Dense Plasma A. B. Zylstra,1,*

    E-Print Network [OSTI]

    Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA 2 to cold matter, consistent with a reduced mean ionization potential. The data agree with stopping models fusion. Dense plasmas in the warm-dense matter (WDM) regime, approx- imately solid density and tens of e

  13. 1506 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 32, NO. 4, AUGUST 2004 Predictability of Large Geomagnetic Disturbances

    E-Print Network [OSTI]

    is based upon work supported by CISM, which is funded by the STC Program of the National Science Foundation

  14. An in-situ accelerator-based diagnostic for plasma-material interactions science in magnetic fusion devices

    E-Print Network [OSTI]

    Hartwig, Zachary Seth

    2014-01-01

    Plasma-material interactions (PMI) in magnetic fusion devices such as fuel retention, material erosion and redeposition, and material mixing present significant scientific and engineering challenges, particularly for the ...

  15. The evolution of ion charge states in cathodic vacuum arc plasmas: a review

    SciTech Connect (OSTI)

    Anders, Andre

    2011-12-18

    Cathodic vacuum arc plasmas are known to contain multiply charged ions. 20 years after “Pressure Ionization: its role in metal vapour vacuum arc plasmas and ion sources” appeared in vol. 1 of Plasma Sources Science and Technology, it is a great opportunity to re-visit the issue of pressure ionization, a non-ideal plasma effect, and put it in perspective to the many other factors that influence observable charge state distributions, such as the role of the cathode material, the path in the density-temperature phase diagram, the “noise” in vacuum arc plasma as described by a fractal model approach, the effects of external magnetic fields and charge exchange collisions with neutrals. A much more complex image of the vacuum arc plasma emerges putting decades of experimentation and modeling in perspective.

  16. Gyrokinetic simulations of electron density fluctuations and comparisons with measurements

    E-Print Network [OSTI]

    Budny, Robert

    density fluctuations, APS, Orlando, FL, Nov, 2007PRINCETON PLASMA PHYSICS LABORATORY PPPL 1 #12, Gyrokinetic simulations of electron density fluctuations, APS, Orlando, FL, Nov, 2007PRINCETON PLASMA PHYSICS simulations of electron density fluctuations, APS, Orlando, FL, Nov, 2007PRINCETON PLASMA PHYSICS LABORATORY

  17. Science

    E-Print Network [OSTI]

    Department of Mathematics, Statistics, and Computer Science, University of Illinois. at Chicago, Chicago, IL, 60607, USA. 2 Department of Mathematics, Purdue ...

  18. Turbulence & Transport in Burning Plasmas

    E-Print Network [OSTI]

    , General Atomics, U. Maryland, PPPL, U. Colorado, UCLA, U. Texas) DOE Scientific Discovery Through Advanced Sciences, SciDAC (Scientific Discovery Through Advanced Computing) Project · devoted to studying plasma of toroidal plasma: plasma = heavy fluid B = "light fluid" geff = centrifugal force R v 2 R Growth rate: RLRLL

  19. 728 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 34, NO. 3, JUNE 2006 The Electron Diffusion Coefficient in Energy

    E-Print Network [OSTI]

    Kaganovich, Igor

    Coefficient in Energy in Bounded Collisional Plasmas Lev D. Tsendin Abstract--The electron energies in typical, the momentum relaxation in collisions with neutrals is sig- nificantly faster than the energy relaxation due be de- scribed by a diffusion coefficient in energy . Both collisional and stochastic heating mechanisms

  20. 146 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 27, NO. 1, FEBRUARY 1999 Video Imaging of Dust Acoustic Waves

    E-Print Network [OSTI]

    Merlino, Robert L.

    Acoustic Waves C. Thompson, A. Barkan, R. L. Merlino, and N. D'Angelo Fig. 1. Single video frame image of a dust acoustic wave. The bright vertical bands correspond to the wave crests (dust compressions "dust waves." A sample image of a dust acoustic wave is presented. Index Terms--Image analysis, plasma

  1. ADVANCES IN APPLIED PLASMA SCIENCE, Vol.9, 2013 ISAPS '13, Istanbul Dynamic Simulation of Materials Modification and Deuterium

    E-Print Network [OSTI]

    Harilal, S. S.

    depends on many factors where consequences of plasma/wall interactions can be considered as the most of Materials Modification and Deuterium Retention in Tokamak Fusion Environment Tatyana Sizyuk and Ahmed various materials for coating of reactor walls, e.g., Be for the first wall and W and C for the divertor

  2. Planetary and Space Science 55 (2007) 17721792 The Analyser of Space Plasmas and Energetic Atoms (ASPERA-4)

    E-Print Network [OSTI]

    California at Berkeley, University of

    2007-01-01

    wind­atmosphere interaction and characterise the plasma and neutral gas environment in the near fields affect the Venusian atmosphere? The ASPERA-4 instrument comprises four sensors; two ENA sensors flux (0.1­60 keV) with no mass and energy resolution but relatively high angular resolution

  3. 516 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 33, NO. 2, APRIL 2005 Simulation of Self-Erase Discharge Waveforms

    E-Print Network [OSTI]

    Veronis, Georgios

    . THE plasma display panel (PDP) is one of the leading candi- dates in the competition for large-size high-definition research is the improvement of the luminous efficiency. A number of different approaches have been pursued of the elec- tron mean energy, which is determined by solving the electron energy equation. We use a finite

  4. An in situ accelerator-based diagnostic for plasma-material interactions science on magnetic fusion devices

    SciTech Connect (OSTI)

    Hartwig, Zachary S.; Barnard, Harold S.; Lanza, Richard C.; Sorbom, Brandon N.; Stahle, Peter W.; Whyte, Dennis G. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge Massachusetts 02139 (United States)] [Plasma Science and Fusion Center, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge Massachusetts 02139 (United States)

    2013-12-15

    This paper presents a novel particle accelerator-based diagnostic that nondestructively measures the evolution of material surface compositions inside magnetic fusion devices. The diagnostic's purpose is to contribute to an integrated understanding of plasma-material interactions in magnetic fusion, which is severely hindered by a dearth of in situ material surface diagnosis. The diagnostic aims to remotely generate isotopic concentration maps on a plasma shot-to-shot timescale that cover a large fraction of the plasma-facing surface inside of a magnetic fusion device without the need for vacuum breaks or physical access to the material surfaces. Our instrument uses a compact (?1 m), high-current (?1 milliamp) radio-frequency quadrupole accelerator to inject 0.9 MeV deuterons into the Alcator C-Mod tokamak at MIT. We control the tokamak magnetic fields – in between plasma shots – to steer the deuterons to material surfaces where the deuterons cause high-Q nuclear reactions with low-Z isotopes ?5 ?m into the material. The induced neutrons and gamma rays are measured with scintillation detectors; energy spectra analysis provides quantitative reconstruction of surface compositions. An overview of the diagnostic technique, known as accelerator-based in situ materials surveillance (AIMS), and the first AIMS diagnostic on the Alcator C-Mod tokamak is given. Experimental validation is shown to demonstrate that an optimized deuteron beam is injected into the tokamak, that low-Z isotopes such as deuterium and boron can be quantified on the material surfaces, and that magnetic steering provides access to different measurement locations. The first AIMS analysis, which measures the relative change in deuterium at a single surface location at the end of the Alcator C-Mod FY2012 plasma campaign, is also presented.

  5. Perspective on the Role of Negative Ions and Ion-Ion Plasmas in Heavy Ion Fusion Science, Magnetic Fusion Energy, and Related Fields

    E-Print Network [OSTI]

    Kwan, J.W.

    2008-01-01

    Fusion Science, Magnetic Fusion Energy, and Related Fieldsof Science, Office of Fusion Energy Sciences, of the U.S.Fusion Science, Magnetic Fusion Energy, and Related Fields

  6. Plasma heating power dissipation in low temperature hydrogen plasmas

    E-Print Network [OSTI]

    Komppula, J

    2015-01-01

    Theoretical framework for power dissipation in low temperature plasmas in corona equilibrium is developed. The framework is based on fundamental conservation laws and reaction cross sections and is only weakly sensitive to plasma parameters, e.g. electron temperature and density. The theory is applied to low temperature atomic and molecular hydrogen laboratory plasmas for which the plasma heating power dissipation to photon emission, ionization and chemical potential is calculated. The calculated photon emission is compared to recent experimental results.

  7. Fusion Energy Sciences

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

    Fusion Energy Sciences Fusion Energy Sciences Expanding the fundamental understanding of matter at very high temperatures and densities and to build the scientific foundation...

  8. Development and Benchmarking of a Hybrid PIC Code For Dense Plasmas and Fast Ignition

    SciTech Connect (OSTI)

    Witherspoon, F. Douglas; Welch, Dale R.; Thompson, John R.; MacFarlane, Joeseph J.; Phillips, Michael W.; Bruner, Nicki; Mostrom, Chris; Thoma, Carsten; Clark, R. E.; Bogatu, Nick; Kim, Jin-Soo; Galkin, Sergei; Golovkin, Igor E.; Woodruff, P. R.; Wu, Linchun; Messer, Sarah J.

    2014-05-20

    Radiation processes play an important role in the study of both fast ignition and other inertial confinement schemes, such as plasma jet driven magneto-inertial fusion, both in their effect on energy balance, and in generating diagnostic signals. In the latter case, warm and hot dense matter may be produced by the convergence of a plasma shell formed by the merging of an assembly of high Mach number plasma jets. This innovative approach has the potential advantage of creating matter of high energy densities in voluminous amount compared with high power lasers or particle beams. An important application of this technology is as a plasma liner for the flux compression of magnetized plasma to create ultra-high magnetic fields and burning plasmas. HyperV Technologies Corp. has been developing plasma jet accelerator technology in both coaxial and linear railgun geometries to produce plasma jets of sufficient mass, density, and velocity to create such imploding plasma liners. An enabling tool for the development of this technology is the ability to model the plasma dynamics, not only in the accelerators themselves, but also in the resulting magnetized target plasma and within the merging/interacting plasma jets during transport to the target. Welch pioneered numerical modeling of such plasmas (including for fast ignition) using the LSP simulation code. Lsp is an electromagnetic, parallelized, plasma simulation code under development since 1995. It has a number of innovative features making it uniquely suitable for modeling high energy density plasmas including a hybrid fluid model for electrons that allows electrons in dense plasmas to be modeled with a kinetic or fluid treatment as appropriate. In addition to in-house use at Voss Scientific, several groups carrying out research in Fast Ignition (LLNL, SNL, UCSD, AWE (UK), and Imperial College (UK)) also use LSP. A collaborative team consisting of HyperV Technologies Corp., Voss Scientific LLC, FAR-TECH, Inc., Prism Computational Sciences, Inc. and Advanced Energy Systems Inc. joined efforts to develop new physics and numerical models for LSP in several key areas to enhance the ability of LSP to model high energy density plasmas (HEDP). This final report details those efforts. Areas addressed in this research effort include: adding radiation transport to LSP, first in 2D and then fully 3D, extending the EMHD model to 3D, implementing more advanced radiation and electrode plasma boundary conditions, and installing more efficient implicit numerical algorithms to speed complex 2-D and 3-D computations. The new capabilities allow modeling of the dominant processes in high energy density plasmas, and further assist the development and optimization of plasma jet accelerators, with particular attention to MHD instabilities and plasma/wall interaction (based on physical models for ion drag friction and ablation/erosion of the electrodes). In the first funding cycle we implemented a solver for the radiation diffusion equation. To solve this equation in 2-D, we used finite-differencing and applied the parallelized sparse-matrix solvers in the PETSc library (Argonne National Laboratory) to the resulting system of equations. A database of the necessary coefficients for materials of interest was assembled using the PROPACEOS and ATBASE codes from Prism. The model was benchmarked against Prism's 1-D radiation hydrodynamics code HELIOS, and against experimental data obtained from HyperV's separately funded plasma jet accelerator development program. Work in the second funding cycle focused on extending the radiation diffusion model to full 3-D, continued development of the EMHD model, optimizing the direct-implicit model to speed up calculations, add in multiply ionized atoms, and improved the way boundary conditions are handled in LSP. These new LSP capabilities were then used, along with analytic calculations and Mach2 runs, to investigate plasma jet merging, plasma detachment and transport, restrike and advanced jet accelerator design. In addition, a strong linkage to diagnostic measureme

  9. Gun Injection into a Microwave Plasma J. C. Sprott

    E-Print Network [OSTI]

    Sprott, Julien Clinton

    Gun Injection into a Microwave Plasma by J. C. Sprott May, 1970 Plasma Studies University high densities by rapid pulsed gun injection. TIlis no te describes measurements made -Cwo years ago in which a gun plasma was injected into a background microwave plasma of variable density in the toroidal

  10. Review: engineering particles using the aerosol-through-plasma method

    SciTech Connect (OSTI)

    Phillips, Jonathan; Luhrs, Claudia C; Richard, Monique

    2009-01-01

    For decades, plasma processing of materials on the nanoscale has been an underlying enabling technology for many 'planar' technologies, particularly virtually every aspect of modern electronics from integrated-circuit fabrication with nanoscale elements to the newest generation of photovoltaics. However, it is only recent developments that suggest that plasma processing can be used to make 'particulate' structures of value in fields, including catalysis, drug delivery, imaging, higher energy density batteries, and other forms of energy storage. In this paper, the development of the science and technology of one class of plasma production of particulates, namely, aerosol-through-plasma (A-T-P), is reviewed. Various plasma systems, particularly RF and microwave, have been used to create nanoparticles of metals and ceramics, as well as supported metal catalysts. Gradually, the complexity of the nanoparticles, and concomitantly their potential value, has increased. First, unique two-layer particles were generated. These were postprocessed to create unique three-layer nanoscale particles. Also, the technique has been successfully employed to make other high-value materials, including carbon nanotubes, unsupported graphene, and spherical boron nitride. Some interesting plasma science has also emerged from efforts to characterize and map aerosol-containing plasmas. For example, it is clear that even a very low concentration of particles dramatically changes plasma characteristics. Some have also argued that the local-thermodynamic-equilibrium approach is inappropriate to these systems. Instead, it has been suggested that charged- and neutral-species models must be independently developed and allowed to 'interact' only in generation terms.

  11. Tapered plasma channels to phase-lock accelerating and focusing forces in laser-plasma accelerators

    SciTech Connect (OSTI)

    Rittershofer, W.; Schroeder, C.B.; Esarey, E.; Gruner, F.J.; Leemans, W.P.

    2010-05-17

    Tapered plasma channels are considered for controlling dephasing of a beam with respect to a plasma wave driven by a weakly-relativistic, short-pulse laser. Tapering allows for enhanced energy gain in a single laser plasma accelerator stage. Expressions are derived for the taper, or longitudinal plasma density variation, required to maintain a beam at a constant phase in the longitudinal and/or transverse fields of the plasma wave. In a plasma channel, the phase velocities of the longitudinal and transverse fields differ, and, hence, the required tapering differs. The length over which the tapered plasma density becomes singular is calculated. Linear plasma tapering as well as discontinuous plasma tapering, which moves beams to adjacent plasma wave buckets, are also considered. The energy gain of an accelerated electron in a tapered laser-plasma accelerator is calculated and the laser pulse length to optimize the energy gain is determined.

  12. Closed inductively coupled plasma cell

    DOE Patents [OSTI]

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

    1990-11-06

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

  13. Science

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory ofDidDevelopment Top LDRDUniversitySchedules Print Current Science

  14. Science

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation ofAlbuquerque| Stanford SynchrotronVideo-Contest Sign In AboutBiologicalScience

  15. An innovative high-power constant-current pulsed-arc power-supply for a high-density pulsed-arc-plasma ion-source using a LaB{sub 6}-filament

    SciTech Connect (OSTI)

    Ueno, A.; Oguri, H.; Ikegami, K.; Namekawa, Y.; Ohkoshi, K.; Tokuchi, A.

    2010-02-15

    An innovative high-power constant-current (CC) pulsed-arc (PA) power-supply (PS) indispensable for a high-density PA plasma ion-source using a lanthanum hexaboride (LaB{sub 6}) filament was devised by combining a constant-voltage (CV) PA-PS, which is composed of an insulated gate bipolar transistor (IGBT) switch, a CV direct-current (dc) PS and a 270 mF capacitor with a CC-PA-PS, which is composed of an IGBT-switch, a CC-dc-PS and a 400 {mu}H inductor, through the inductor. The hybrid-CC-PA-PS succeeded in producing a flat arc-pulse with a peak power of 56 kW (400 Ax140 V) and a duty factor of more than 1.5%(600 {mu}sx25 Hz) for Japan Proton Accelerator Research Complex (J-PARC) H{sup -} ion-source stably. It also succeeded in shortening the 99% rising-time of the arc-pulse-current to about 20 {mu}s and tilting up or down the arc-pulse-current arbitrarily and almost linearly by changing the setting voltage of its CV-dc-PS.

  16. Plasma Physics

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

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

  17. High-Energy-Density Plasmas, Fluids

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory ofDid you notHeat Pumps Heat Pumps An error occurred. Try|

  18. FUSION NUCLEAR SCIENCE PROGRAM & SUPPORTING FUSION NUCLEAR SCIENCE FACILITY (FNSF)

    E-Print Network [OSTI]

    FUSION NUCLEAR SCIENCE PROGRAM & SUPPORTING FUSION NUCLEAR SCIENCE FACILITY (FNSF): UPDATE in order to apply the knowledge we gained about burning plasma state #12;FUSION NUCLEAR SCIENCE PROGRAM #12;FUSION NUCLEAR SCIENCE PROGRAM DEVELOPMENT OF ELEMENTS OF THE FUSION NUCLEAR SCIENCE PROGRAM

  19. Plasma density diagnostic for capillary-discharge based plasma channels

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTech ConnectSpeeding accessusers' guide.representation (Conference) |(Journal(Journal

  20. Cosmological Perturbations of Ultrarelativistic Plasmas

    E-Print Network [OSTI]

    Dominik J. Schwarz

    1996-07-31

    Scalar cosmological perturbations of a weakly self-interacting plasma mixed with a perfect radiation fluid are investigated. Effects of this plasma are considered through order $\\lambda^{3/2}$ of perturbative thermal-field-theory in the radiation dominated universe. The breakdown of thermal perturbation theory at vastly subhorizon scales is circumvented by a Pad\\'e approximant solution. Compared to collisionless plasmas the phase speed and subhorizon damping of the plasma density perturbations are changed. An example for a self-interacting thermal field is provided by the neutrinos with effective 4-fermion interactions.

  1. Merging of high speed argon plasma jets

    SciTech Connect (OSTI)

    Case, A.; Messer, S.; Brockington, S.; Wu, L.; Witherspoon, F. D.; Elton, R.

    2013-01-15

    Formation of an imploding plasma liner for the plasma liner experiment (PLX) requires individual plasma jets to merge into a quasi-spherical shell of plasma converging on the origin. Understanding dynamics of the merging process requires knowledge of the plasma phenomena involved. We present results from the study of the merging of three plasma jets in three dimensional geometry. The experiments were performed using HyperV Technologies Corp. 1 cm Minirailguns with a preionized argon plasma armature. The vacuum chamber partially reproduces the port geometry of the PLX chamber. Diagnostics include fast imaging, spectroscopy, interferometry, fast pressure probes, B-dot probes, and high speed spatially resolved photodiodes, permitting measurements of plasma density, temperature, velocity, stagnation pressure, magnetic field, and density gradients. These experimental results are compared with simulation results from the LSP 3D hybrid PIC code.

  2. Integrating Experiment and Theory in Electrochemical Surface Science: Studies on the Molecular Adsorption on Noble-Metal Electrode Surfaces by Density Functional Theory, Electron Spectroscopy, and Electrochemistry 

    E-Print Network [OSTI]

    Javier, Alnald Caintic

    2013-08-05

    Computational techniques based on density functional theory (DFT) and experimental methods based on electrochemistry (EC), electrochemical scanning tunneling microscopy (EC-STM), and high-resolution electron energy loss spectroscopy (HREELS) were...

  3. Control of focusing forces and emittances in plasma-based accelerators using near-hollow plasma channels

    SciTech Connect (OSTI)

    Schroeder, C. B.; Esarey, E.; Benedetti, C.; Leemans, W. P.

    2013-08-15

    A near-hollow plasma channel, where the plasma density in the channel is much less than the plasma density in the walls, is proposed to provide independent control over the focusing and accelerating forces in a plasma accelerator. In this geometry the low density in the channel contributes to the focusing forces, while the accelerating fields are determined by the high density in the channel walls. The channel also provides guiding for intense laser pulses used for wakefield excitation. Both electron and positron beams can be accelerated in a nearly symmetric fashion. Near-hollow plasma channels can effectively mitigate emittance growth due to Coulomb scattering for high-energy physics applications.

  4. National Ignition Facility & Photon Science

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

    nuclear astrophysics, material properties, plasma physics, nonlinear optical physics, radiation sources, radiative properties, and other areas of science. NIF will generate...

  5. Plasma generating apparatus for large area plasma processing

    DOE Patents [OSTI]

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

    1991-07-16

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

  6. Plasma generating apparatus for large area plasma processing

    DOE Patents [OSTI]

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

    1991-01-01

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

  7. Neutral depletion and the helicon density limit

    SciTech Connect (OSTI)

    Magee, R. M.; Galante, M. E.; Carr, J. Jr.; Lusk, G.; McCarren, D. W.; Scime, E. E.

    2013-12-15

    It is straightforward to create fully ionized plasmas with modest rf power in a helicon. It is difficult, however, to create plasmas with density >10{sup 20} m{sup ?3}, because neutral depletion leads to a lack of fuel. In order to address this density limit, we present fast (1 MHz), time-resolved measurements of the neutral density at and downstream from the rf antenna in krypton helicon plasmas. At the start of the discharge, the neutral density underneath the antenna is reduced to 1% of its initial value in 15 ?s. The ionization rate inferred from these data implies that the electron temperature near the antenna is much higher than the electron temperature measured downstream. Neutral density measurements made downstream from the antenna show much slower depletion, requiring 14 ms to decrease by a factor of 1/e. Furthermore, the downstream depletion appears to be due to neutral pumping rather than ionization.

  8. Plasma Simulation Program

    SciTech Connect (OSTI)

    Greenwald, Martin

    2011-10-04

    Many others in the fusion energy and advanced scientific computing communities participated in the development of this plan. The core planning team is grateful for their important contributions. This summary is meant as a quick overview the Fusion Simulation Program's (FSP's) purpose and intentions. There are several additional documents referenced within this one and all are supplemental or flow down from this Program Plan. The overall science goal of the DOE Office of Fusion Energy Sciences (FES) Fusion Simulation Program (FSP) is to develop predictive simulation capability for magnetically confined fusion plasmas at an unprecedented level of integration and fidelity. This will directly support and enable effective U.S. participation in International Thermonuclear Experimental Reactor (ITER) research and the overall mission of delivering practical fusion energy. The FSP will address a rich set of scientific issues together with experimental programs, producing validated integrated physics results. This is very well aligned with the mission of the ITER Organization to coordinate with its members the integrated modeling and control of fusion plasmas, including benchmarking and validation activities. [1]. Initial FSP research will focus on two critical Integrated Science Application (ISA) areas: ISA1, the plasma edge; and ISA2, whole device modeling (WDM) including disruption avoidance. The first of these problems involves the narrow plasma boundary layer and its complex interactions with the plasma core and the surrounding material wall. The second requires development of a computationally tractable, but comprehensive model that describes all equilibrium and dynamic processes at a sufficient level of detail to provide useful prediction of the temporal evolution of fusion plasma experiments. The initial driver for the whole device model will be prediction and avoidance of discharge-terminating disruptions, especially at high performance, which are a critical impediment to successful operation of machines like ITER. If disruptions prove unable to be avoided, their associated dynamics and effects will be addressed in the next phase of the FSP.

  9. Ac#vi#es of the US Burning Plasma Organiza#on

    E-Print Network [OSTI]

    ;Goals of the USBPO · Coordinate and advocate US burning plasma (BP) research=ons · USBPO ­ Coordinates US burning plasma research, to advance scien=fic understanding USBPO organizes the US Fusion Energy Science community to support burning plasma

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

    E-Print Network [OSTI]

    Ji, Hantao

    2007-01-01

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

  11. Plasma diagnostic reflectometry

    SciTech Connect (OSTI)

    Cohen, B.I.; Afeyan, B.B.; Garrison, J.C.; Kaiser, T.B.; Luhmann, N.C. Jr.; Domier, C.W.; Chou, A.E.; Baang, S.

    1996-02-26

    Theoretical and experimental studies of plasma diagnostic reflectometry have been undertaken as a collaborative research project between the Lawrence Livermore National Laboratory (LLNL) and the University of California Department of Applied Science Plasma Diagnostics Group under the auspices of the Laboratory Directed Research and Development Program at LLNL. Theoretical analyses have explored the basic principles of reflectometry to understand its limitations, to address specific gaps in the understanding of reflectometry measurements in laboratory experiments, and to explore extensions of reflectometry such as ultra-short-pulse reflectometry. The theory has supported basic laboratory reflectometry experiments where reflectometry measurements can be corroborated by independent diagnostic measurements.

  12. Development and Optimization of Modular Hybrid Plasma Reactor...

    Office of Scientific and Technical Information (OSTI)

    Optimization of Modular Hybrid Plasma Reactor N A 36 MATERIALS SCIENCE INL developed a bench-scale, modular hybrid plasma system for gas-phase nanomaterials synthesis. The system...

  13. MIT Plasma Science & Fusion Center

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

    Facility Information Tokamak Data & Real-Time Information Computer & Data Systems Research Program Information Publications & News Meetings & Seminars Contact Information Physics...

  14. Alfven wave tomography for cold magnetohydrodynamic plasmas I. Y. Dodin and N. J. Fisch

    E-Print Network [OSTI]

    ARTICLES Alfve´n wave tomography for cold magnetohydrodynamic plasmas I. Y. Dodin and N. J. Fisch; accepted 12 December 2001 Alfve´n wave propagation in slightly nonuniform cold plasmas is studied by means of quasistatic plasma density perturbations. The Alfve´n waves are shown not to affect the plasma density

  15. Confinement of Plasma along Shaped Open Magnetic Fields from the Centrifugal Force of Supersonic Plasma Rotation

    SciTech Connect (OSTI)

    Teodorescu, C.; Young, W. C.; Swan, G. W. S.; Ellis, R. F.; Hassam, A. B.; Romero-Talamas, C. A. [University of Maryland, College Park, Maryland 20742 (United States)

    2010-08-20

    Interferometric density measurements in plasmas rotating in shaped, open magnetic fields demonstrate strong confinement of plasma parallel to the magnetic field, with density drops of more than a factor of 10. Taken together with spectroscopic measurements of supersonic ExB rotation of sonic Mach 2, these measurements are in agreement with ideal MHD theory which predicts large parallel pressure drops balanced by centrifugal forces in supersonically rotating plasmas.

  16. INTERACTION OF MUON BEAM WITH PLASMA DEVELOPED DURING IONIZATION COOLING

    SciTech Connect (OSTI)

    S. Ahmed, D. Kaplan, T. Roberts, L. Spentzouris, K. Beard

    2012-07-01

    Particle-in-cell simulations involving the interaction of muon beam (peak density 10{sup 18} m{sup 3}) with Li plasma (ionized medium) of density 10{sup 16}-10{sup 22} m{sup -3} have been performed. This study aimed to understand the effects of plasma on an incoming beam in order to explore scenario developed during the process of ionization cooling. The computer code takes into account the self-consistent electromagnetic effects of beam interacting with plasma. This study shows that the beam can pass through the plasma of densities four order of magnitude higher than its peak density. The low density plasmas are wiped out by the beam, however, the resonance is observed for densities of similar order. Study reveals the signature of plasma wakefield acceleration.

  17. Science & Technology - 2015

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

    example is the use of betatron x-ray radiation for research in the growing field of high energy density (HED) science on extremely short time and length scales (energy density is...

  18. June 21, 2014 1 Fusion Energy Sciences: Workforce Development Needs

    E-Print Network [OSTI]

    represent a vibrant component of plasma science research and likely will remain so in the foreseeable future

  19. PLASMA PHYSICS AND FUSION TECHNOLOGY; GRAPHITE; CREEP; PHYSICAL...

    Office of Scientific and Technical Information (OSTI)

    creep of graphite) Kennedy, C.R. 36 MATERIALS SCIENCE; 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; GRAPHITE; CREEP; PHYSICAL RADIATION EFFECTS; JAPAN; MEETINGS; TRAVEL; ASIA; CARBON;...

  20. Aerodynamic Focusing Of High-Density Aerosols

    SciTech Connect (OSTI)

    Ruiz, D. E.; Fisch, Nathaniel

    2014-02-24

    High-density micron-sized particle aerosols might form the basis for a number of applications in which a material target with a particular shape might be quickly ionized to form a cylindrical or sheet shaped plasma. A simple experimental device was built in order to study the properties of high-density aerosol focusing for 1#22; m silica spheres. Preliminary results recover previous findings on aerodynamic focusing at low densities. At higher densities, it is demonstrated that the focusing properties change in a way which is consistent with a density dependent Stokes number.

  1. Chaos in a complex plasma

    SciTech Connect (OSTI)

    Sheridan, T.E. [Department of Physics and Astronomy, Ohio Northern University, Ada, Ohio 45810 (United States)

    2005-08-15

    Chaotic dynamics is observed experimentally in a complex (dusty) plasma of three particles. A low-frequency sinusoidal modulation of the plasma density excites both the center-of-mass and breathing modes. Low-dimensional chaos is seen for a 1:2 resonance between these modes. A strange attractor with a dimension of 2.48{+-}0.05 is observed. The largest Lyapunov exponent is positive.

  2. Neutrino oscillations in a turbulent plasma

    SciTech Connect (OSTI)

    Mendonça, J. T.; Haas, F.

    2013-07-15

    A new model for the joint neutrino flavor and plasma oscillations is introduced, in terms of the dynamics of the neutrino flavor polarization vector in a plasma background. Fundamental solutions are found for both time-invariant and time-dependent media, considering slow and fast variations of the electron plasma density. The model is shown to be described by a generalized Hamiltonian formalism. In the case of a broad spectrum of electron plasma waves, a statistical approach indicates the shift of both equilibrium value and frequency oscillation of flavor coherence, due to the existence of a turbulent plasma background.

  3. Plasma Physics

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

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

  4. Cathodic Vacuum Arc Plasma of Thallium

    E-Print Network [OSTI]

    Yushkov, Georgy Yu.; Anders, Andre

    2006-01-01

    P. J. Martin, Handbook of Vacuum Arc Science and Technology.charge state distributions of vacuum arc plasmas: The originand the broadening of vacuum-arc ion charge state

  5. Hutch Neilson Princeton Plasma Physics Laboratory

    E-Print Network [OSTI]

    fusion science. Status · Physics basis for compact stellarator experiments. · Design. · ConstructionNCSX Hutch Neilson Princeton Plasma Physics Laboratory Fusion Power Associates Symposium Gaithersburg, MD December 13, 2004 The Promise and Status of Compact Stellarators #12;2 NCSX Compact

  6. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 31, NO. 4, AUGUST 2003 745 Study of the Effects of ECH Power and Pulse Length

    E-Print Network [OSTI]

    -GHz 500-kW gyrotron tube being made by Communications and Power Industries. The ECH preionization to start the plasma current; and (c) somewhat reduce the Volt-s expenditure from the transformer needed]. The Modeling efforts of Fidone and Granata [5] showed that for a large tokamak, energy deposition would

  7. 212 IEEE TRANSACTIONSON NUCLEAR SCIENCE,VOL. 43, NO. 1,FEBRUARY 1996 Management of Real Time Processes for Plasma Parameter Qpti

    E-Print Network [OSTI]

    Zachmann, Gabriel

    , Germany Abstract Beyond optimization of position and shape control, producing high performance plasmas value control processes must be given a means to interact with each other. This adds to the complexity a new conceptual layer for management of real time processes. I n Active real time control

  8. Boundary Plasma Turbulence Simulations for Tokamaks

    SciTech Connect (OSTI)

    Xu, X; Umansky, M; Dudson, B; Snyder, P

    2008-05-15

    The boundary plasma turbulence code BOUT models tokamak boundary-plasma turbulence in a realistic divertor geometry using modified Braginskii equations for plasma vorticity, density (ni), electron and ion temperature (T{sub e}; T{sub i}) and parallel momenta. The BOUT code solves for the plasma fluid equations in a three dimensional (3D) toroidal segment (or a toroidal wedge), including the region somewhat inside the separatrix and extending into the scrape-off layer; the private flux region is also included. In this paper, a description is given of the sophisticated physical models, innovative numerical algorithms, and modern software design used to simulate edge-plasmas in magnetic fusion energy devices. The BOUT code's unique capabilities and functionality are exemplified via simulations of the impact of plasma density on tokamak edge turbulence and blob dynamics.

  9. Plasma valve

    DOE Patents [OSTI]

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

    2003-01-01

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

  10. Plasma response to electron energy filter in large volume plasma device

    SciTech Connect (OSTI)

    Sanyasi, A. K.; Awasthi, L. M.; Mattoo, S. K.; Srivastava, P. K.; Singh, S. K.; Singh, R.; Kaw, P. K. [Institute for Plasma Research, Gandhinagar, 382 428 Gujarat (India)] [Institute for Plasma Research, Gandhinagar, 382 428 Gujarat (India)

    2013-12-15

    An electron energy filter (EEF) is embedded in the Large Volume Plasma Device plasma for carrying out studies on excitation of plasma turbulence by a gradient in electron temperature (ETG) described in the paper of Mattoo et al. [S. K. Mattoo et al., Phys. Rev. Lett. 108, 255007 (2012)]. In this paper, we report results on the response of the plasma to the EEF. It is shown that inhomogeneity in the magnetic field of the EEF switches on several physical phenomena resulting in plasma regions with different characteristics, including a plasma region free from energetic electrons, suitable for the study of ETG turbulence. Specifically, we report that localized structures of plasma density, potential, electron temperature, and plasma turbulence are excited in the EEF plasma. It is shown that structures of electron temperature and potential are created due to energy dependence of the electron transport in the filter region. On the other hand, although structure of plasma density has origin in the particle transport but two distinct steps of the density structure emerge from dominance of collisionality in the source-EEF region and of the Bohm diffusion in the EEF-target region. It is argued and experimental evidence is provided for existence of drift like flute Rayleigh-Taylor in the EEF plasma.

  11. Ion optical effects in a low pressure rf plasma

    SciTech Connect (OSTI)

    Oechsner, Hans; Paulus, Hubert [Institute for Surface and Thin Film Analysis IFOS and Department of Physics, Technical University of Kaiserslautern, D-67663 Kaiserslautern (Germany)] [Institute for Surface and Thin Film Analysis IFOS and Department of Physics, Technical University of Kaiserslautern, D-67663 Kaiserslautern (Germany)

    2013-11-15

    Ion optical effects in low pressure gas discharges are introduced as a novel input into low pressure plasma technology. They are based on appropriate geometrical plasma confinements which enable a control of the shape of internal density and potential distributions and, hence, the ion motion in the plasma bulk. Such effects are exemplified for an electron cyclotron wave resonance plasma in Ar at 1–5 × 10{sup ?3} millibars. The geometry of the plasma chamber is modified by a conical and a cylindrical insert. Computer simulations display spherical plasma density contours to be formed around the conical confinement. This effects an increase of the ratio of the ion currents into the conical and the cylindrical inserts which depends on the fourth power of the plasma electron temperature. A quantitative understanding of this behavior is presented. As another essential result, the shape of the internal plasma contours is found to be independent of the pressure controlled plasma parameters.

  12. Microwave Interferometer Density Diagnostic for the Levitated Dipole Experiment

    E-Print Network [OSTI]

    Microwave Interferometer Density Diagnostic for the Levitated Dipole Experiment A. Boxer, J. Kesner the density profile of the plasma in LDX, we are constructing a multi-channel microwave interferometer be inverted to reconstruct a radially symmetric density profile. The microwave interferometer of LDX

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

    SciTech Connect (OSTI)

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

    2014-11-01

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

  14. Vortex stabilized electron beam compressed fusion grade plasma

    SciTech Connect (OSTI)

    Hershcovitch, Ady

    2014-03-19

    Most inertial confinement fusion schemes are comprised of highly compressed dense plasmas. Those schemes involve short, extremely high power, short pulses of beams (lasers, particles) applied to lower density plasmas or solid pellets. An alternative approach could be to shoot an intense electron beam through very dense, atmospheric pressure, vortex stabilized plasma.

  15. Laser beat wave excitation of terahertz radiation in a plasma slab

    SciTech Connect (OSTI)

    Chauhan, Santosh; Parashar, Jetendra

    2014-10-15

    Terahertz (THz) radiation generation by nonlinear mixing of lasers, obliquely incident on a plasma slab is investigated. Two cases are considered: (i) electron density profile is parabolic but density peak is below the critical density corresponding to the beat frequency, (ii) plasma boundaries are sharp and density is uniform. In both cases, nonlinearity arises through the ponderomotive force that gives rise to electron drift at the beat frequency. In the case of inhomogeneous plasma, non zero curl of the nonlinear current density gives rise to electromagnetic THz generation. In case of uniform plasma, the sharp density variation at the plasma boundaries leads to radiation generation. In a slab width of less than a terahertz wavelength, plasma density one fourth of terahertz critical density, laser intensities ?10{sup 17?}W/cm{sup 2} at 1??m, one obtains the THz intensity ?1?GW/cm{sup 2} at 3 THz radiation frequency.

  16. Application of Plasma Waveguides to High Energy Accelerators

    SciTech Connect (OSTI)

    Milchberg, Howard M

    2013-03-30

    The eventual success of laser-plasma based acceleration schemes for high-energy particle physics will require the focusing and stable guiding of short intense laser pulses in reproducible plasma channels. For this goal to be realized, many scientific issues need to be addressed. These issues include an understanding of the basic physics of, and an exploration of various schemes for, plasma channel formation. In addition, the coupling of intense laser pulses to these channels and the stable propagation of pulses in the channels require study. Finally, new theoretical and computational tools need to be developed to aid in the design and analysis of experiments and future accelerators. Here we propose a 3-year renewal of our combined theoretical and experimental program on the applications of plasma waveguides to high-energy accelerators. During the past grant period we have made a number of significant advances in the science of laser-plasma based acceleration. We pioneered the development of clustered gases as a new highly efficient medium for plasma channel formation. Our contributions here include theoretical and experimental studies of the physics of cluster ionization, heating, explosion, and channel formation. We have demonstrated for the first time the generation of and guiding in a corrugated plasma waveguide. The fine structure demonstrated in these guides is only possible with cluster jet heating by lasers. The corrugated guide is a slow wave structure operable at arbitrarily high laser intensities, allowing direct laser acceleration, a process we have explored in detail with simulations. The development of these guides opens the possibility of direct laser acceleration, a true miniature analogue of the SLAC RF-based accelerator. Our theoretical studies during this period have also contributed to the further development of the simulation codes, Wake and QuickPIC, which can be used for both laser driven and beam driven plasma based acceleration schemes. We will continue our development of advanced simulation tools by modifying the QuickPIC algorithm to allow for the simulation of plasma particle pick-up by the wake fields. We have also performed extensive simulations of plasma slow wave structures for efficient THz generation by guided laser beams or accelerated electron beams. We will pursue experimental studies of direct laser acceleration, and THz generation by two methods, ponderomotive-induced THz polarization, and THz radiation by laser accelerated electron beams. We also plan to study both conventional and corrugated plasma channels using our new 30 TW in our new lab facilities. We will investigate production of very long hydrogen plasma waveguides (5 cm). We will study guiding at increasing power levels through the onset of laser-induced cavitation (bubble regime) to assess the role played by the preformed channel. Experiments in direct acceleration will be performed, using laser plasma wakefields as the electron injector. Finally, we will use 2-colour ionization of gases as a high frequency THz source (<60 THz) in order for femtosecond measurements of low plasma densities in waveguides and beams.

  17. A novel zirconium K{alpha} imager for high energy density physics...

    Office of Scientific and Technical Information (OSTI)

    of Publication: United States Language: English Subject: 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; COMPUTERIZED...

  18. Characteristic of a triple-cathode vacuum arc plasma source

    SciTech Connect (OSTI)

    Xiang, W.; Li, M.; Chen, L.

    2012-02-15

    In order to generate a better ion beam, a triple-cathode vacuum arc plasma source has been developed. Three plasma generators in the vacuum arc plasma source are equally located on a circle. Each generator initiated by means of a high-voltage breakdown between the cathode and the anode could be operated separately or simultaneously. The arc plasma expands from the cathode spot region in vacuum. In order to study the behaviors of expanding plasma plume generated in the vacuum arc plasma source, a Langmuir probe array is employed to measure the saturated ion current of the vacuum arc plasma source. The time-dependence profiles of the saturated current density of the triple vacuum arc plasma source operated separately and simultaneously are given. Furthermore, the plasma characteristic of this vacuum arc plasma source is also presented in the paper.

  19. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 24, NO. 3, JUNE 1996 879 A Neural-Network Model of th.e Input/Output

    E-Print Network [OSTI]

    discusses an approach to model the inputloutput characteristics of the Sinus-6 electron beam accelerator to accurately describe the inputloutput behavior of the Sinus-6-driven backward wave oscillator (BWO of New Mexico Pulsed Power and TPlasma Science Laboratory, in collaboration with the systems group

  20. Method of accelerating photons by a relativistic plasma wave

    DOE Patents [OSTI]

    Dawson, John M. (Pacific Palisades, CA); Wilks, Scott C. (Santa Monica, CA)

    1990-01-01

    Photons of a laser pulse have their group velocity accelerated in a plasma as they are placed on a downward density gradient of a plasma wave of which the phase velocity nearly matches the group velocity of the photons. This acceleration results in a frequency upshift. If the unperturbed plasma has a slight density gradient in the direction of propagation, the photon frequencies can be continuously upshifted to significantly greater values.

  1. Solitary and shock waves in magnetized electron-positron plasma

    SciTech Connect (OSTI)

    Lu, Ding; Li, Zi-Liang; Abdukerim, Nuriman; Xie, Bai-Song

    2014-02-15

    An Ohm's law for electron-positron (EP) plasma is obtained. In the framework of EP magnetohydrodynamics, we investigate nonrelativistic nonlinear waves' solutions in a magnetized EP plasma. In the collisionless limit, quasistationary propagating solitary wave structures for the magnetic field and the plasma density are obtained. It is found that the wave amplitude increases with the Mach number and the Alfvén speed. However, the dependence on the plasma temperature is just the opposite. Moreover, for a cold EP plasma, the existence range of the solitary waves depends only on the Alfvén speed. For a hot EP plasma, the existence range depends on the Alfvén speed as well as the plasma temperature. In the presence of collision, the electromagnetic fields and the plasma density can appear as oscillatory shock structures because of the dissipation caused by the collisions. As the collision frequency increases, the oscillatory shock structure becomes more and more monotonic.

  2. NSTX Plasma Response to Lithium Coated Divertor

    SciTech Connect (OSTI)

    H.W. Kugel, M.G. Bell, J.P. Allain, R.E. Bell, S. Ding, S.P. Gerhardt, M.A. Jaworski, R. Kaita, J. Kallman, S.M. Kaye, B.P. LeBlanc, R. Maingi, R. Majeski, R. Maqueda, D.K. Mansfield, D. Mueller, R. Nygren, S.F. Paul, R. Raman, A.L. Roquemore, S.A. Sabbagh, H. Schneider, C.H. Skinner, V.A. Soukhanovskii, C.N. Taylor, J.R. Timberlak, W.R. Wampler, L.E. Zakharov, S.J. Zweben, and the NSTX Research Team

    2011-01-21

    NSTX experiments have explored lithium evaporated on a graphite divertor and other plasma facing components in both L- and H- mode confinement regimes heated by high-power neutral beams. Improvements in plasma performance have followed these lithium depositions, including a reduction and eventual elimination of the HeGDC time between discharges, reduced edge neutral density, reduced plasma density, particularly in the edge and the SOL, increased pedestal electron and ion temperature, improved energy confinement and the suppression of ELMs in the H-mode. However, with improvements in confinement and suppression of ELMs, there was a significant secular increase in the effective ion charge Zeff and the radiated power in H-mode plasmas as a result of increases in the carbon and medium-Z metallic impurities. Lithium itself remained at a very low level in the plasma core, <0.1%. Initial results are reported from operation with a Liquid Lithium Divertor (LLD) recently installed.

  3. Principles of Rotating Plasma in Plasma Propulsion Systems N. J. Fisch

    E-Print Network [OSTI]

    Principles of Rotating Plasma in Plasma Propulsion Systems N. J. Fisch Department of Astrophysical Sciences Princeton University 33rd International Electric Propulsion Conference (IEPC2013 in crossed electric and magnetic fields. This talk reviews at a tutorial level some of the interesting

  4. Science Park Science Park

    E-Print Network [OSTI]

    Koolen, Marijn

    Science Park Science Park Science Park Science Park Science Park Kruislaan Kruislaan Science Park SURFsara NLeSC Polder Anna Hoeve Telecity Matrix Innovation Center AUC AMOLF ARCNL UvA Faculty of Science Equinix Universum CWI UvA Oerknal Meet & Eat Maslow Spar ACE Venture Lab IXA ILCA NS Amsterdam Science

  5. Small, high frequency probe for internal magnetic field measurements in high temperature plasmas

    E-Print Network [OSTI]

    Washington at Seattle, University of

    temperature 50 eV , high density ( 1020 m 3 ) plasmas such as the field-reversed configuration FRC , it has eV , high density ( 1020 m 3 ) plasmas such as the field-reversed configuration FRC , it has be exposed to the plasma. An estimate of the limiting probe size for the FRC can be obtained from

  6. Characteristics of plasma properties in an ablative pulsed plasma thruster

    SciTech Connect (OSTI)

    Schoenherr, Tony; Nees, Frank; Arakawa, Yoshihiro; Komurasaki, Kimiya; Herdrich, Georg

    2013-03-15

    Pulsed plasma thrusters are electric space propulsion devices which create a highly transient plasma bulk in a short-time arc discharge that is expelled to create thrust. The transitional character and the dependency on the discharge properties are yet to be elucidated. In this study, optical emission spectroscopy and Mach-Zehnder interferometry are applied to investigate the plasma properties in variation of time, space, and discharge energy. Electron temperature, electron density, and Knudsen numbers are derived for the plasma bulk and discussed. Temperatures were found to be in the order of 1.7 to 3.1 eV, whereas electron densities showed maximum values of more than 10{sup 17} cm{sup -3}. Both values showed strong dependency on the discharge voltage and were typically higher closer to the electrodes. Capacitance and time showed less influence. Knudsen numbers were derived to be in the order of 10{sup -3}-10{sup -2}, thus, indicating a continuum flow behavior in the main plasma bulk.

  7. Electromagnetic Solitons in Degenerate Relativistic Electron-Positron Plasma

    E-Print Network [OSTI]

    Berezhiani, V I; Tsintsadze, N L

    2014-01-01

    The existence of soliton-like electromagnetic (EM) distributions in a fully degenerate electron-positron plasma is studied applying relativistic hydrodynamic and Maxwell equations. For circularly polarized wave it is found that the soliton solutions exist both in relativistic as well as nonrelativistic degenerate plasmas. Plasma density in the region of soliton pulse localization is reduced considerably. The possibility of plasma cavitation is also shown.

  8. COLLOQUIUM: Handling Plasma Wall Interactions on ITER | Princeton Plasma

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room News PublicationsAudits &Bradbury ScienceComplexPlasmaPhysicsPlasma

  9. Linear accelerator design study with direct plasma injection scheme for warm dense matter

    SciTech Connect (OSTI)

    Kondo, K.; Kanesue, T; Okamura, M.

    2011-03-28

    Warm Dense Matter (WDM) is a challenging science field, which is related to heavy ion inertial fusion and planetary science. It is difficult to expect the behavior because the state with high density and low temperature is completely different from ideal condition. The well-defined WDM generation is required to understand it. Moderate energy ion beams ({approx} MeV/u) slightly above Bragg peak is an advantageous method for WDM because of the uniform energy deposition. Direct Plasma Injection Scheme (DPIS) with a Interdigital H-mode (IH) accelerator has a potential for the beam parameter. We show feasible parameters of the IH accelerator for WDM. WDM physics is a challenging science and is strongly related to Heavy Ion Fusion science. WDM formation by Direct Plasma Injection Scheme (DPIS) with IH accelerator, which is a compact system, is proposed. Feasible parameters for IH accelerator are shown for WDM state. These represents that DPIS with IH accelerator can access a different parameter region of WDM.

  10. HEAVY ION FUSION SCIENCE VIRTUAL NATIONAL LABORATORY 4th QUARTER 2008 MILESTONE REPORT

    E-Print Network [OSTI]

    Bieniosek, F.M.

    2008-01-01

    density of two cathodic arc plasma sources (two-FCAPS) by anby fabricating four cathodic arc plasma sources (four-FCAPS)four filtered cathodic arc plasma sources; (b) photograph of

  11. The Heavy Ion Fusion Science Virtual National Laboratory

    E-Print Network [OSTI]

    Gilson, Erik

    Final Focus Solenoid and Target Chamber ­ Cathodic Arc Plasma Source (CAPS) Developed by André AndersThe Heavy Ion Fusion Science Virtual National Laboratory Plasma Sources for Drivers and NDCX-II 19 P. Gilson Princeton Plasma Physics Laboratory #12;The Heavy Ion Fusion Science Virtual National

  12. Measurements of plasma bremsstrahlung and plasma energy density produced by electron cyclotron resonance ion source plasmas

    E-Print Network [OSTI]

    Noland, Jonathan David

    2011-01-01

    30] Glenn F. Knoll. Radiation Detection and Measurement.in many textbooks on radiation detection[30], and a brief

  13. Measurements of plasma bremsstrahlung and plasma energy density produced by electron cyclotron resonance ion source plasmas

    E-Print Network [OSTI]

    Noland, Jonathan David

    2011-01-01

    vi 3.2.6 Diagram of Klystron pulsingFigure 3.2.6: Diagram of Klystron pulsing circuit. linkare several ways to pulse a Klystron, Fig. 3.2.6 shows a

  14. Measurements of plasma bremsstrahlung and plasma energy density produced by electron cyclotron resonance ion source plasmas

    E-Print Network [OSTI]

    Noland, Jonathan David

    2011-01-01

    as function of time. Right: electron energy as function ofas function of time. Right: electron energy as function ofas function of time. Right: electron energy as function of

  15. Effect of argon addition on plasma parameters and dust charging in hydrogen plasma

    SciTech Connect (OSTI)

    Kakati, B. Kausik, S. S.; Saikia, B. K.; Bandyopadhyay, M.; Saxena, Y. C.

    2014-10-28

    Experimental results on effect of adding argon gas to hydrogen plasma in a multi-cusp dusty plasma device are reported. Addition of argon modifies plasma density, electron temperature, degree of hydrogen dissociation, dust current as well as dust charge. From the dust charging profile, it is observed that the dust current and dust charge decrease significantly up to 40% addition of argon flow rate in hydrogen plasma. But beyond 40% of argon flow rate, the changes in dust current and dust charge are insignificant. Results show that the addition of argon to hydrogen plasma in a dusty plasma device can be used as a tool to control the dust charging in a low pressure dusty plasma.

  16. PU AST558, 4/25/05 ST Science & Fusion Energy Martin Peng

    E-Print Network [OSTI]

    plasma particles and waves interact? · How do hot plasmas interact with walls? · How to supply magnetic PPPL Spherical Tokamak Plasma Science & Fusion Energy Development Supported by Columbia U Comp Tokamak (ST) Offers Rich Plasma Science Opportunities and High Fusion Energy Potential · What is ST

  17. L-Mode Plasmas in Alcator C-Mod I. Cziegler, J. L. Terry, B....

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

    C-Mod I. Cziegler, J. L. Terry, B. LaBombard MIT - Plasma Science and Fusion Center APS Division of Plasma Physics Orlando FL, November 2007 Background and Motivation Both L-...

  18. A large volume uniform plasma generator for the experiments of electromagnetic wave propagation in plasma

    SciTech Connect (OSTI)

    Yang Min; Li Xiaoping; Xie Kai; Liu Donglin; Liu Yanming

    2013-01-15

    A large volume uniform plasma generator is proposed for the experiments of electromagnetic (EM) wave propagation in plasma, to reproduce a 'black out' phenomenon with long duration in an environment of the ordinary laboratory. The plasma generator achieves a controllable approximate uniform plasma in volume of 260 mm Multiplication-Sign 260 mm Multiplication-Sign 180 mm without the magnetic confinement. The plasma is produced by the glow discharge, and the special discharge structure is built to bring a steady approximate uniform plasma environment in the electromagnetic wave propagation path without any other barriers. In addition, the electron density and luminosity distributions of plasma under different discharge conditions were diagnosed and experimentally investigated. Both the electron density and the plasma uniformity are directly proportional to the input power and in roughly reverse proportion to the gas pressure in the chamber. Furthermore, the experiments of electromagnetic wave propagation in plasma are conducted in this plasma generator. Blackout phenomena at GPS signal are observed under this system and the measured attenuation curve is of reasonable agreement with the theoretical one, which suggests the effectiveness of the proposed method.

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

    SciTech Connect (OSTI)

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

    2014-04-28

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

  20. Science Outreach Science Outreach

    E-Print Network [OSTI]

    Kavanagh, Karen L.

    Science Outreach Science Outreach AT SFU'S FACULTY OF SCIENCE OUR PASSION IS SCIENCE EDUCATION At SFU's Faculty of Science our passion is science education #12;coming sooncoming soon The Trottier 2015. The Trottier Observatory will be an anchor for a science plaza located in front of Strand Hall

  1. Flush-mounted probe diagnostics for argon glow discharge plasma

    SciTech Connect (OSTI)

    Xu, Liang Cao, Jinxiang; Liu, Yu; Wang, Jian; Du, Yinchang; Zheng, Zhe; Zhang, Xiao; Wang, Pi; Zhang, Jin; Li, Xiao; Qin, Yongqiang; Zhao, Liang

    2014-09-15

    A comparison is made between plasma parameters measured by a flush-mounted probe (FP) and a cylindrical probe (CP) in argon glow discharge plasma. Parameters compared include the space potential, the plasma density, and the effective electron temperature. It is found that the ion density determined by the FP agrees well with the electron density determined by the CP in the quasi-neutral plasma to better than 10%. Moreover, the space potential and effective electron temperature calculated from electron energy distribution function measured by the FP is consistent with that measured by the CP over the operated discharge current and pressure ranges. These results present the FP can be used as a reliable diagnostic tool in the stable laboratory plasma and also be anticipated to be applied in other complicated plasmas, such as tokamaks, the region of boundary-layer, and so on.

  2. AT ROCHESTER Arts, sciences & engineering

    E-Print Network [OSTI]

    Portman, Douglas

    & Tissue - Medical Imaging - Medical Technology Innovation - Neuroengineering · Brain and Cognitive - Biomechanics - Fusion, Plasma & HEDP - Materials Sciences - Precision Machining & Optics Manufacturing · Optics (PhD, MS) · Philosophy (PhD) · Photographic Preservation and Collections Management (MA) · Physics

  3. Electronically swept millimetre-wave interferometer for spatially resolved measurement of plasma electron

    E-Print Network [OSTI]

    Howard, John

    electron density John Howard and David Oliver Plasma Research Laboratory, Research School of Physical, located in the Plasma Research Laboratory at the Australian National University, is a flexible, medium

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

    E-Print Network [OSTI]

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

    2006-01-01

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

  5. Kando, M.; Esirkepov, T.Zh.; and others 70 PLASMA PHYSICS AND...

    Office of Scientific and Technical Information (OSTI)

    targets Pirozhkov, A.S.; Kando, M.; Esirkepov, T.Zh.; and others 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; BEAM-PLASMA SYSTEMS; ELECTRON DENSITY; EV RANGE; HARMONIC GENERATION;...

  6. A restoration model of distorted electron density in wave-cutoff probe measurement

    SciTech Connect (OSTI)

    Jun, Hyun-Su Lee, Yun-Seong

    2014-02-15

    This study investigates the problem of electron density distortion and how the density can be restored in a wave-cutoff probe. Despite recent plasma diagnostics research using a wave-cutoff probe, the problem of electron density distortion caused by plasma conditions has not been resolved. Experimental results indicate that electron density measured using the wave-cutoff method is highly susceptible to variations in the probe tip gap. This electron density distortion is caused by the bulk plasma disturbance between probe tips, and it must be removed for calculating the absolute electron density. To do this, a detailed analytic model was developed using the power balance equation near probe tips. This model demonstrates the characteristics of plasma distortion in wave-cutoff probe measurement and successfully restored the absolute value of electron density with varying probe tip gaps.

  7. Feibush and his three students in the Science Education summer internship program had some fun with a giant 3-D image of a plasma with the help of PPPL

    E-Print Network [OSTI]

    Budny, Robert

    A Collaborative National Center for Fusion & Plasma Research Together at last: PPPL binds the heart of the NSTX

  8. Nanotube array controlled carbon plasma deposition

    SciTech Connect (OSTI)

    Qian, Shi; Cao, Huiliang; Liu, Xuanyong; Ding, Chuanxian

    2013-06-17

    Finding approaches to control the elementary processes of plasma-solid interactions and direct the fluxes of matter at nano-scales becomes an important aspect in science. This letter reports that, by taking advantages of the spacing characteristics of discrete TiO{sub 2} nanotube arrays, the flying trajectories and the subsequent implantation and deposition manner of energetic carbon ions can be directed and controlled to fabricate hollow conical arrays. The study provides an alternative method for plasma nano-manufacturing.

  9. RECENT PROGRESS IN THE DEVELOPMENT OF DUCTILE-PHASE TOUGHENED TUNGSTEN FOR PLASMA-FACING MATERIALS

    SciTech Connect (OSTI)

    Henager, Charles H.; Kurtz, Richard J.; Roosendaal, Timothy J.; Borlaug, Brennan A.; Odette, George R.; Cunningham, Kevin; Fields, Kirk A.; Gragg, David; Zok, Frank W.

    2014-03-03

    The objective of this study is to develop the materials science of fiber-reinforced tungsten composites as candidates for plasma-facing components in future fusion reactors.

  10. Volumetric plasma source development and characterization.

    SciTech Connect (OSTI)

    Crain, Marlon D. (National Security Technologies, LLC, Las Vegas, NV); Maron, Yitzhak (Weizmann Institute of Science, Rehovot, Israel); Oliver, Bryan Velten; Starbird, Robert L. (National Security Technologies, LLC, Las Vegas, NV); Johnston, Mark D.; Hahn, Kelly Denise; Mehlhorn, Thomas Alan; Droemer, Darryl W. (National Security Technologies, LLC, Las Vegas, NV); National Security Technologies, LLC, Las Vegas, NV

    2008-09-01

    The development of plasma sources with densities and temperatures in the 10{sup 15}-10{sup 17} cm{sup -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{sup 15} to mid-10{sup 16} cm{sup -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.

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

    SciTech Connect (OSTI)

    Edward, Jr., Thomas

    2014-09-19

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

  12. Spectroscopic Determination of the Magnetic Fields in Exploding Wire and X-pinch Plasmas

    SciTech Connect (OSTI)

    Hammer, David A.

    2013-12-19

    In this report, we summarize the progress that was made toward developing a new magnetic field diagnostic known as Zeeman Broadening for current carrying high energy density plasmas.

  13. Fusion programs in applied plasma physics

    SciTech Connect (OSTI)

    Not Available

    1992-02-01

    The objectives of the theoretical science program are: To support the interpretation of present experiments and predict the outcome of future planned experiments; to improve on existing models and codes and validate against experimental results; and to conduct theoretical physics development of advanced concepts with applications for DIII-D and future devices. Major accomplishments in FY91 include the corroboration between theory and experiment on MHD behavior in the second stable regime of operation on DIII-D, and the frequency and mode structure of toroidal Alfven eigenmodes in high beta, shaped plasmas. We have made significant advances in the development of the gyro-Landau fluid approach to turbulence simulation which more accurately models kinetic drive and damping mechanisms. Several theoretical models to explain the bifurcation phenomenon in L- to H-mode transition were proposed providing the theoretical basis for future experimental verification. The capabilities of new rf codes have been upgraded in response to the expanding needs of the rf experiments. Codes are being employed to plan for a fully non-inductive current drive experiment in a high beta, enhanced confinement regime. GA's experimental effort in Applied Physics encompasses two advanced diagnostics essential for the operation of future fusion experiments: Alpha particle diagnostic, and current and density profile diagnostics. This paper discusses research in all these topics.

  14. 2-D studies of Relativistic electron beam plasma instabilities in an inhomogeneous plasma

    E-Print Network [OSTI]

    Shukla, Chandrashekhar; Patel, Kartik

    2015-01-01

    Relativistic electron beam propagation in plasma is fraught with several micro instabilities like two stream, filamentation etc., in plasma. This results in severe limitation of the electron transport through a plasma medium. Recently, however, there has been an experimental demonstration of improved transport of Mega Ampere of electron currents (generated by the interaction of intense laser with solid target) in a carbon nanotube structured solid target [Phys. Rev Letts. 108, 235005 (2012)]. This then suggests that the inhomogeneous plasma (created by the ionization of carbon nano tube structured target) helps in containing the growth of the beam plasma instabilities. This manuscript addresses this issue with the help of a detailed analytical study and simulations with the help of 2-D Particle - In - Cell code. The study conclusively demonstrates that the growth rate of the dominant instability in the 2-D geometry decreases when the plasma density is chosen to be inhomogeneous, provided the scale length 1/ks...

  15. ECR apparatus with magnetic coil for plasma refractive index control

    DOE Patents [OSTI]

    Berry, Lee A. (Oak Ridge, TN)

    1994-01-01

    The present invention describes a technique to control the radial profile of microwave power in an ECR plasma discharge. In order to provide for a uniform plasma density to a specimen, uniform energy absorption by the plasma is desired. By controlling the radial profile of the microwave power transmitted through the microwave window of a reactor, the profile of the transmitted energy to the plasma can be controlled in order to have uniform energy absorption by the plasma. An advantage of controlling the profile using the window transmission characteristics is that variations to the radial profile of microwave power can be made without changing the microwave coupler or reactor design.

  16. Optimized ECR plasma apparatus with varied microwave window thickness

    DOE Patents [OSTI]

    Berry, Lee A. (Oak Ridge, TN)

    1995-01-01

    The present invention describes a technique to control the radial profile of microwave power in an ECR plasma discharge. In order to provide for a uniform plasma density to a specimen, uniform energy absorption by the plasma is desired. By controlling the radial profile of the microwave power transmitted through the microwave window of a reactor, the profile of the transmitted energy to the plasma can be controlled in order to have uniform energy absorption by the plasma. An advantage of controlling the profile using the window transmission characteristics is that variations to the radial profile of microwave power can be made without changing the microwave coupler or reactor design.

  17. Reproducing continuous radio blackout using glow discharge plasma

    SciTech Connect (OSTI)

    Xie, Kai; Li, Xiaoping; Liu, Donglin; Shao, Mingxu [School of Aerospace Science and Technology, Xidian University, Xi'an 710071 (China)] [School of Aerospace Science and Technology, Xidian University, Xi'an 710071 (China); Zhang, Hanlu [School of Communication and Information Engineering, Xi'an University of Posts and Telecommunications, Xi'an 710121 (China)] [School of Communication and Information Engineering, Xi'an University of Posts and Telecommunications, Xi'an 710121 (China)

    2013-10-15

    A novel plasma generator is described that offers large-scale, continuous, non-magnetized plasma with a 30-cm-diameter hollow structure, which provides a path for an electromagnetic wave. The plasma is excited by a low-pressure glow discharge, with varying electron densities ranging from 10{sup 9} to 2.5 × 10{sup 11} cm{sup ?3}. An electromagnetic wave propagation experiment reproduced a continuous radio blackout in UHF-, L-, and S-bands. The results are consistent with theoretical expectations. The proposed method is suitable in simulating a plasma sheath, and in researching communications, navigation, electromagnetic mitigations, and antenna compensation in plasma sheaths.

  18. Optimized ECR plasma apparatus with varied microwave window thickness

    DOE Patents [OSTI]

    Berry, L.A.

    1995-11-14

    The present invention describes a technique to control the radial profile of microwave power in an ECR plasma discharge. In order to provide for a uniform plasma density to a specimen, uniform energy absorption by the plasma is desired. By controlling the radial profile of the microwave power transmitted through the microwave window of a reactor, the profile of the transmitted energy to the plasma can be controlled in order to have uniform energy absorption by the plasma. An advantage of controlling the profile using the window transmission characteristics is that variations to the radial profile of microwave power can be made without changing the microwave coupler or reactor design. 9 figs.

  19. ECR apparatus with magnetic coil for plasma refractive index control

    DOE Patents [OSTI]

    Berry, L.A.

    1994-04-26

    The present invention describes a technique to control the radial profile of microwave power in an ECR plasma discharge. In order to provide for a uniform plasma density to a specimen, uniform energy absorption by the plasma is desired. By controlling the radial profile of the microwave power transmitted through the microwave window of a reactor, the profile of the transmitted energy to the plasma can be controlled in order to have uniform energy absorption by the plasma. An advantage of controlling the profile using the window transmission characteristics is that variations to the radial profile of microwave power can be made without changing the microwave coupler or reactor design. 9 figures.

  20. Plasma wake field XUV radiation source

    DOE Patents [OSTI]

    Prono, Daniel S. (Los Alamos, NM); Jones, Michael E. (Los Alamos, NM)

    1997-01-01

    A XUV radiation source uses an interaction of electron beam pulses with a gas to create a plasma radiator. A flowing gas system (10) defines a circulation loop (12) with a device (14), such as a high pressure pump or the like, for circulating the gas. A nozzle or jet (16) produces a sonic atmospheric pressure flow and increases the density of the gas for interacting with an electron beam. An electron beam is formed by a conventional radio frequency (rf) accelerator (26) and electron pulses are conventionally formed by a beam buncher (28). The rf energy is thus converted to electron beam energy, the beam energy is used to create and then thermalize an atmospheric density flowing gas to a fully ionized plasma by interaction of beam pulses with the plasma wake field, and the energetic plasma then loses energy by line radiation at XUV wavelengths Collection and focusing optics (18) are used to collect XUV radiation emitted as line radiation when the high energy density plasma loses energy that was transferred from the electron beam pulses to the plasma.

  1. 356 OPTICS LETTERS / Vol. 25, No. 5 / March 1, 2000 Dense plasma diagnostics with an amplitude-division

    E-Print Network [OSTI]

    Rocca, Jorge J.

    beam limit the maximum electron density, plasma size, and plasma density gradient that can be probed356 OPTICS LETTERS / Vol. 25, No. 5 / March 1, 2000 Dense plasma diagnostics with an amplitude. The interferometer, which utilizes grazing-incidence diffraction gratings as beam splitters in a modified Mach

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

    SciTech Connect (OSTI)

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

    2008-08-01

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

  3. Nanodiamonds in dusty low-pressure plasmas

    SciTech Connect (OSTI)

    Vandenbulcke, L.; Gries, T.; Rouzaud, J. N.

    2009-01-26

    Dusty plasmas composed of carbon, hydrogen, and oxygen have been evidenced by optical emission spectroscopy and microwave interferometry, due to the increase in electron energy and the decrease in electron density. These plasmas allow homogeneous synthesis of nanodiamond grains composed of either pure diamond nanocrystals only (2-10 nm in size) or of diamond nanocrystals and some sp{sup 2}-hybridized carbon entities. The control of their size and their microstructure could open ways for a wide range of fields. Their formation from a plasma-activated gaseous phase is also attractive because the formation of nanodiamonds in the universe is still a matter of controversy.

  4. Stability of relativistic plasma-vacuum interfaces

    E-Print Network [OSTI]

    Yuri Trakhinin

    2011-11-18

    We study the plasma-vacuum interface problem in relativistic magnetohydrodynamics for the case when the plasma density does not go to zero continuously, but jumps. In the vacuum region we consider the Maxwell equations for electric and magnetic fields. We show that a sufficiently large vacuum electric field can make the planar interface violently unstable. By using a suitable secondary symmetrization of the vacuum Maxwell equations, we find a sufficient condition that precludes violent instabilities. Under this condition we derive an energy a priori estimate in the anisotropic weighted Sobolev space $H^1_*$ for the variable coefficients linearized problem for nonplanar plasma-vacuum interfaces.

  5. Plasma Physics

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

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

  6. IOP PUBLISHING PLASMA PHYSICS AND CONTROLLED FUSION Plasma Phys. Control. Fusion 51 (2009) 055018 (22pp) doi:10.1088/0741-3335/51/5/055018

    E-Print Network [OSTI]

    Carlos III de Madrid, Universidad

    2009-01-01

    IOP PUBLISHING PLASMA PHYSICS AND CONTROLLED FUSION Plasma Phys. Control. Fusion 51 (2009) 055018 Eduardo Ahedo1 and Jes´us J Ramos Plasma Science and Fusion Center, Massachusetts Institute of Technology the extremely cold limit where the mode growth rate would become sonic or supersonic. Conversely, the effects

  7. Langmuir Probe Measurements in Plasma Shadows

    SciTech Connect (OSTI)

    Waldmann, O.; Koch, B.; Fussmann, G.

    2006-01-15

    When immersing a target into a plasma streaming along magnetic field lines, a distinct shadow region extending over large distances is observed by the naked eye downstream of the target.In this work we present an experimental study of the effect applying Langmuir probes. In contrast to expectations, there are only marginal changes in the profiles of temperature and density behind masks that cut away about 50% of the plasma cross-section. On the other hand, the mean density is drastically reduced by an order of magnitude. First attempts to simulate the observations by solving the classical 2D diffusion equation were not successful.

  8. Laboratory Density Functionals

    E-Print Network [OSTI]

    B. G. Giraud

    2007-07-26

    We compare several definitions of the density of a self-bound system, such as a nucleus, in relation with its center-of-mass zero-point motion. A trivial deconvolution relates the internal density to the density defined in the laboratory frame. This result is useful for the practical definition of density functionals.

  9. Secretary Steven Chu Visits Princeton Plasma Physics Laboratory...

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

    said has been at the center of the intellectual birth and coming of age of plasma and fusion science. Discussing our need for scientists to address our country's energy issues,...

  10. Shock compression of low-density foams

    SciTech Connect (OSTI)

    Holmes, N.C.

    1993-07-01

    Shock compression of very low density micro-cellular materials allows entirely new regimes of hot fluid states to be investigated experimentally. Using a two-stage light-gas gun to generate strong shocks, temperatures of several eV are readily achieved at densities of roughly 0.5--1 g/cm{sup 3} in large, uniform volumes. The conditions in these hot, expanded fluids are readily found using the Hugoniot jump conditions. We will briefly describe the basic methodology for sample preparation and experimental measurement of shock velocities. We present data for several materials over a range of initial densities. This paper will explore the applications of these methods for investigations of equations of state and phase diagrams, spectroscopy, and plasma physics. Finally, we discus the need for future work on these and related low-density materials.

  11. Magneto-inertial Fusion: An Emerging Concept for Inertial Fusion and Dense Plasmas in Ultrahigh Magnetic Fields

    SciTech Connect (OSTI)

    Thio, Francis Y.C.

    2008-01-01

    An overview of the U.S. program in magneto-inertial fusion (MIF) is given in terms of its technical rationale, scientific goals, vision, research plans, needs, and the research facilities currently available in support of the program. Magneto-inertial fusion is an emerging concept for inertial fusion and a pathway to the study of dense plasmas in ultrahigh magnetic fields (magnetic fields in excess of 500 T). The presence of magnetic field in an inertial fusion target suppresses cross-field thermal transport and potentially could enable more attractive inertial fusion energy systems. A vigorous program in magnetized high energy density laboratory plasmas (HED-LP) addressing the scientific basis of magneto-inertial fusion has been initiated by the Office of Fusion Energy Sciences of the U.S. Department of Energy involving a number of universities, government laboratories and private institutions.

  12. Impact of anomalous dispersion on the interferometer measurements of plasmas

    SciTech Connect (OSTI)

    Nilsen, J; Johnson, W R; Iglesias, C A; Scofield, J H

    2004-12-16

    For many decades optical interferometers have been used to measure the electron density of plasmas. During the last ten years X-ray lasers in the wavelength range 14 to 47 nm have enabled researchers to use interferometers to probe even higher density plasmas. The data analysis assumes that the index of refraction is due only to the free electrons, which makes the index of refraction less than one and the electron density proportional to the number of fringe shifts. Recent experiments in Al plasmas observed plasmas with an index of refraction greater than one and made us question the validity of the usual formula for calculating the index of refraction. Recent calculations showed how the anomalous dispersion from the bound electrons can dominate the index of refraction in many types of plasma and make the index greater than one or enhance the index such that one would greatly overestimate the electron density of the plasma using interferometers. In this work we calculate the index of refraction of C, Al, Ti, and Pd plasmas for photon energies from 0 to 100 eV (12.4 nm) using a new average-atom code. The results show large variations from the free electron approximation under many different plasma conditions. We validate the average-atom code against the more detailed OPAL code for carbon and aluminum plasmas. During the next decade X-ray free electron lasers and other sources will be available to probe a wider variety of plasmas at higher densities and shorter wavelengths so understanding the index of refraction in plasmas will be even more essential.

  13. PPPL researchers present cutting edge results at APS Plasma Physics...

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

    to advanced warning of the disturbances and an improved ability to cope with them. Using radio waves to control density in fusion plasma Experiments show how heating electrons in...

  14. Greg Hammett Imperial College, London & Princeton Plasma Physics Lab

    E-Print Network [OSTI]

    Hammett, Greg

    Corona & Wind Gyrokinetic Simulations Needed & In Progress #12;MHD Turbulence in Astrophysical Plasmas Medium Power Spectrum Of Electron Density Fluctuations Wavenumber (m-1) Power law over ~ 12 orders more & more nonlinear Hypothesize "critical balance": linear time ~ nonlinear time Anisotropic

  15. Ultra-High Intensity Magnetic Field Generation in Dense Plasma

    SciTech Connect (OSTI)

    Fisch, Nathaniel J

    2014-01-08

    I. Grant Objective The main objective of this grant proposal was to explore the efficient generation of intense currents. Whereasthefficient generation of electric current in low-­?energy-­? density plasma has occupied the attention of the magnetic fusion community for several decades, scant attention has been paid to carrying over to high-­?energy-­? density plasma the ideas for steady-­?state current drive developed for low-­?energy-­? density plasma, or, for that matter, to inventing new methodologies for generating electric current in high-­?energy-­?density plasma. What we proposed to do was to identify new mechanisms to accomplish current generation, and to assess the operation, physics, and engineering basis of new forms of current drive in regimes appropriate for new fusion concepts.

  16. Computer tomography of large dust clouds in complex plasmas

    SciTech Connect (OSTI)

    Killer, Carsten; Himpel, Michael; Melzer, André

    2014-10-15

    The dust density is a central parameter of a dusty plasma. Here, a tomography setup for the determination of the three-dimensionally resolved density distribution of spatially extended dust clouds is presented. The dust clouds consist of micron-sized particles confined in a radio frequency argon plasma, where they fill almost the entire discharge volume. First, a line-of-sight integrated dust density is obtained from extinction measurements, where the incident light from an LED panel is scattered and absorbed by the dust. Performing these extinction measurements from many different angles allows the reconstruction of the 3D dust density distribution, analogous to a computer tomography in medical applications.

  17. SCIENCE CHINA Technological Sciences

    E-Print Network [OSTI]

    Liu, Yijun

    turbines, jet engines, nuclear power plants and space crafts, have placed severe demands on highSCIENCE CHINA Technological Sciences © Science China Press and Springer-Verlag Berlin Heidelberg

  18. Course: FUSION SCIENCE AND ENGINEERING Universit degli Studi di Padova

    E-Print Network [OSTI]

    Cesare, Bernardo

    the subject of controlled thermonuclear fusion in magnetically confined plasmas. Both fusion science of Controlled Thermonuclear Fusion, b) Engineering of a Magnetically Confined Fusion Reactor, c) ExperimentalCourse: FUSION SCIENCE AND ENGINEERING Università degli Studi di Padova in agreement

  19. Measurements of an expanding surface flashover plasma

    SciTech Connect (OSTI)

    Harris, J. R., E-mail: john.harris@colostate.edu [Department of Electrical and Computer Engineering, Colorado State University, Fort Collins, Colorado 80523 (United States)

    2014-05-21

    A better understanding of vacuum surface flashover and the plasma produced by it is of importance for electron and ion sources, as well as advanced accelerators and other vacuum electronic devices. This article describes time-of-flight and biased-probe measurements made on the expanding plasma generated from a vacuum surface flashover discharge. The plasma expanded at velocities of 1.2–6.5?cm/?s, and had typical densities of 10{sup 10}–10{sup 12}?cm{sup ?3}. The expansion velocity of the plasma leading edge often exhibited a sharp increase at distances of about 50?mm from the discharge site. Comparison with biased-probe data suggests that, under most conditions, the plasma leading edge was dominated by negative ions, with the apparent increase in velocity being due to fast H{sup ?} overtaking slower, heavier ions. In some cases, biased-probe data also showed abrupt discontinuities in the plasma energy distribution co-located with large changes in the intercepted plasma current, suggesting the presence of a shock in the leading edge of the expanding plasma.

  20. Computational Methods for Collisional Plasma Physics

    SciTech Connect (OSTI)

    Lasinski, B F; Larson, D J; Hewett, D W; Langdon, A B; Still, C H

    2004-02-18

    Modeling the high density, high temperature plasmas produced by intense laser or particle beams requires accurate simulation of a large range of plasma collisionality. Current simulation algorithms accurately and efficiently model collisionless and collision-dominated plasmas. The important parameter regime between these extremes, semi-collisional plasmas, has been inadequately addressed to date. LLNL efforts to understand and harness high energy-density physics phenomena for stockpile stewardship require accurate simulation of such plasmas. We have made significant progress towards our goal: building a new modeling capability to accurately simulate the full range of collisional plasma physics phenomena. Our project has developed a computer model using a two-pronged approach that involves a new adaptive-resolution, ''smart'' particle-in-cell algorithm: complex particle kinetics (CPK); and developing a robust 3D massively parallel plasma production code Z3 with collisional extensions. Our new CPK algorithms expand the function of point particles in traditional plasma PIC models by including finite size and internal dynamics. This project has enhanced LLNL's competency in computational plasma physics and contributed to LLNL's expertise and forefront position in plasma modeling. The computational models developed will be applied to plasma problems of interest to LLNL's stockpile stewardship mission. Such problems include semi-collisional behavior in hohlraums, high-energy-density physics experiments, and the physics of high altitude nuclear explosions (HANE). Over the course of this LDRD project, the world's largest fully electromagnetic PIC calculation was run, enabled by the adaptation of Z3 to the Advanced Simulation and Computing (ASCI) White system. This milestone calculation simulated an entire laser illumination speckle, brought new realism to laser-plasma interaction simulations, and was directly applicable to laser target physics. For the first time, magnetic fields driven by Raman scatter have been observed. Also, Raman rescatter was observed in 2D. This code and its increased suite of dedicated diagnostics are now playing a key role in studies of short-pulse, high-intensity laser matter interactions. In addition, a momentum-conserving electron collision algorithm was incorporated into Z3. Finally, Z3's portability across diverse MPP platforms enabled it to serve the LLNL computing community as a tool for effectively utilizing new machines.

  1. Findiing Science with Science Page 1 Finding Science with Science

    E-Print Network [OSTI]

    Stock, Kristin

    Findiing Science with Science Page 1 Finding Science with Science: Evaluating the Use Stojanovicd , Femke Reitsmae , Lukasz Korczynskif and Boyan Brodaricg a Centre for Geospatial Science of Earth and Ocean Sciences, Cardiff University, Cardiff, UK; e Department of Geography, University

  2. Anatomy of plasma turbulence TAKUMA YAMADA1

    E-Print Network [OSTI]

    Loss, Daniel

    . The plasma is generated by a helicon wave (the radiofrequency (7 MHz) power is 3 kW, excited by a double Mechanics, Kyushu University, 6-1 Kasuga-koen, Kasuga, Fukuoka 816-8580, Japan 2 Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, 6-1 Kasuga-koen, Kasuga, Fukuoka 816-8580, Japan 3

  3. Plasma parameters and electron energy distribution functions in a magnetically focused plasma

    SciTech Connect (OSTI)

    Samuell, C. M.; Blackwell, B. D.; Howard, J.; Corr, C. S. [Plasma Research Laboratory, Research School of Physics and Engineering, Australian National University, Canberra (Australia)

    2013-03-15

    Spatially resolved measurements of ion density, electron temperature, floating potential, and the electron energy distribution function (EEDF) are presented for a magnetically focused plasma. The measurements identify a central plasma column displaying Maxwellian EEDFs at an electron temperature of about 5 eV indicating the presence of a significant fraction of electrons in the inelastic energy range (energies above 15 eV). It is observed that the EEDF remains Maxwellian along the axis of the discharge with an increase in density, at constant electron temperature, observed in the region of highest magnetic field strength. Both electron density and temperature decrease at the plasma radial edge. Electron temperature isotherms measured in the downstream region are found to coincide with the magnetic field lines.

  4. Simulation of ultrashort electron pulse generation from optical injection into wake-field plasma waves

    E-Print Network [OSTI]

    Umstadter, Donald

    Simulation of ultrashort electron pulse generation from optical injection into wake-field plasma waves E. S. Dodd,* J. K. Kim, and D. Umstadter Center for Ultrafast Optical Science, University are focused in a plasma, one exciting a wake-field electron plasma wave while another locally alters some

  5. Passive Spectroscopic Diagnostics for Magnetically-confined Fusion Plasmas

    SciTech Connect (OSTI)

    Stratton, B. C.; Biter, M.; Hill, K. W.; Hillis, D. L.; Hogan, J. T.

    2007-07-18

    Spectroscopy of radiation emitted by impurities and hydrogen isotopes plays an important role in the study of magnetically-confined fusion plasmas, both in determining the effects of impurities on plasma behavior and in measurements of plasma parameters such as electron and ion temperatures and densities, particle transport, and particle influx rates. This paper reviews spectroscopic diagnostics of plasma radiation that are excited by collisional processes in the plasma, which are termed 'passive' spectroscopic diagnostics to distinguish them from 'active' spectroscopic diagnostics involving injected particle and laser beams. A brief overview of the ionization balance in hot plasmas and the relevant line and continuum radiation excitation mechanisms is given. Instrumentation in the soft X-ray, vacuum ultraviolet, ultraviolet, visible, and near-infrared regions of the spectrum is described and examples of measurements are given. Paths for further development of these measurements and issues for their implementation in a burning plasma environment are discussed.

  6. Princeton University Plasma Physics Laboratory, Princeton, New Jersey. Annual report, October 1, 1990--September 30, 1991

    SciTech Connect (OSTI)

    Not Available

    1991-12-31

    This report discusses the following topics: Principal parameters of experimental devices; Tokamak Fusion Test Reactor; Burning Plasma Experiment; Princeton Beta Experiment-Modification; Current Drive Experiment-Upgrade; International Thermonuclear Experimental Reactor; International Collaboration; X-Ray Laser Studies; Hyperthermal Atomic Beam Source; Pure Electron Plasma Experiments; Plasma Processing: Deposition and Etching of Thin Films; Theoretical Studies; Tokamak Modeling; Engineering Department; Environment, Safety, and Health and Quality Assurance; Technology Transfer; Office of Human Resources and Administration; PPPL Patent Invention Disclosures; Office of Resource Management; Graduate Education: Plasma Physics; Graduate Education: Program in Plasma Science and Technology; and Science Education Program.

  7. High-beta plasma effects in a low-pressure helicon plasma

    SciTech Connect (OSTI)

    Corr, C. S.; Boswell, R. W. [Space Plasma, Power and Propulsion Group (SP3), Research School of Physical Science and Engineering, Australian National University, Canberra ACT 0200 (Australia)

    2007-12-15

    In this work, high-beta plasma effects are investigated in a low-pressure helicon plasma source attached to a large volume diffusion chamber. When operating above an input power of 900 W and a magnetic field of 30 G a narrow column of bright blue light (due to Ar II radiation) is observed along the axis of the diffusion chamber. With this blue mode, the plasma density is axially very uniform in the diffusion chamber; however, the radial profiles are not, suggesting that a large diamagnetic current might be induced. The diamagnetic behavior of the plasma has been investigated by measuring the temporal evolution of the magnetic field (B{sub z}) and the plasma kinetic pressure when operating in a pulsed discharge mode. It is found that although the electron pressure can exceed the magnetic field pressure by a factor of 2, a complete expulsion of the magnetic field from the plasma interior is not observed. In fact, under our operating conditions with magnetized ions, the maximum diamagnetism observed is {approx}2%. It is observed that the magnetic field displays the strongest change at the plasma centre, which corresponds to the maximum in the plasma kinetic pressure. These results suggest that the magnetic field diffuses into the plasma sufficiently quickly that on a long time scale only a slight perturbation of the magnetic field is ever observed.

  8. Plasma Control on Existing Devices Experience Gained

    E-Print Network [OSTI]

    · Control of the steady state plasma density profile using a gas valve #12;Jo Lister, CRPP-EPFL, ITPA St state in a finite time"....and less formally..... "Changing the parameters from their natural values · Preprogrammed vertical field and transformer current, gas pre-fill Problem, hitting the wall when parameters

  9. Characterization of BCl3/N-2 plasmas

    E-Print Network [OSTI]

    Sia, S. F.

    2003-08-15

    Optical emission spectroscopy, quadrupole mass spectrometry, and electron density measurements were used to study the effect of the percentage of N-2 on the characteristics of BCl3/N-2 plasmas and their resulting etch processes. The etch rate of Ga...

  10. Non-Local Effects in a Bounded Afterglow Plasma with Fast Electrons

    E-Print Network [OSTI]

    Kaganovich, Igor

    Non-Local Effects in a Bounded Afterglow Plasma with Fast Electrons V. I. Demidov UES, inc. and WVU Electron Temperature and Density in the Afterglow (Post-Discharge) #12;UES Plasma Models · Fluid (continuum-local kinetic models At low pressure, when the plasma scale L is less than electron energy relaxation length

  11. Characterization of a spheromak plasma gun: The effect of refractory electrode coatings

    E-Print Network [OSTI]

    Brown, Michael R.

    Characterization of a spheromak plasma gun: The effect of refractory electrode coatings M. FL Brown, the center electrode of the spheromak plasma gun has been coated with a variety of metals (bare steel, copper in the gun breech was monitored for each of the coated electrodes. Plasma density and temperature

  12. THE JOURNAL OF CHEMICAL PHYSICS 141, 074706 (2014) Rare event molecular dynamics simulations of plasma induced

    E-Print Network [OSTI]

    Henkelman, Graeme

    2014-01-01

    produced from a capillary arc discharge. Plasma from these devices have a density on the or- der of 1026 /m of plasma induced surface ablation Onise Sharia, Jeffrey Holzgrafe, Nayoung Park, and Graeme Henkelman August 2014) The interaction of thermal Ar plasma particles with Si and W surfaces is modeled using

  13. DYNAMICS OF TARGET PLASMA HEATED BY NEUTRAL BEAMS IN A MIRROR Andrey A. Kabantsev

    E-Print Network [OSTI]

    Taskaev, Sergey Yur'evich

    DYNAMICS OF TARGET PLASMA HEATED BY NEUTRAL BEAMS IN A MIRROR Andrey A. Kabantsev Budker Institute(3832)359121 taskaev@inp.nsk.su ABSTRACT Target plasma behavior in a mirror when heated by neutral beams was studied. Considerable changes of target plasma density depending on target quality were found. Neutral beam injection

  14. Extraction of coherent bursts from turbulent edge plasma in magnetic fusion devices using orthogonal wavelets

    E-Print Network [OSTI]

    École Normale Supérieure

    Extraction of coherent bursts from turbulent edge plasma in magnetic fusion devices using, as they determine the confinement properties of the overall plasma in the bulk region and the energy density to be handled by the limiter or divertor components in the shadowed region of the plasma, where the magnetic

  15. Note: On the measurement of plasma potential fluctuations using emissive probes

    SciTech Connect (OSTI)

    Bousselin, G., E-mail: guillaume.bousselin@ens-lyon.fr; Lemoine, N.; Cavalier, J.; Heuraux, S.; Bonhomme, G. [IJL, Université de Lorraine, CNRS (UMR 7198), 54506 Vandoeuvre (France)] [IJL, Université de Lorraine, CNRS (UMR 7198), 54506 Vandoeuvre (France)

    2014-05-15

    In this Note, it is pointed out that emissive probes cannot be used to directly and reliably measure plasma potential fluctuations. An experimentally validated model demonstrates indeed that the floating potential fluctuations of an emissive probe which floats at the mean plasma potential depend not only on the plasma potential fluctuations but also on electron density and temperature fluctuations.

  16. ARDB Technical Note 120 E157 A CONTINUOUS PLASMA FINAL FOCUS

    E-Print Network [OSTI]

    ", in Nonlinear and Relativistic Effects in Plasmas, V. Stefan, ed., (AIP, New York, 1992) pp. 387-401. I am-focussing mechanism, for use in a TeV linear electron-positron collider. They propose to increase the plasma densityARDB Technical Note 120 E157 A CONTINUOUS PLASMA FINAL FOCUS David H. Whittum Preface This report

  17. Anomalous radial transport in tokamak edge plasma

    E-Print Network [OSTI]

    Bodi, Vasudeva Raghavendra Kowsik

    2010-01-01

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

  18. Three regimes of relativistic beam - plasma interaction

    SciTech Connect (OSTI)

    Muggli, P.; Allen, B.; Fang, Y.; Yakimenko, V.; Babzien, M.; Kusche, K.; Fedurin, M.; Vieira, J.; Martins, J.; Silva, L.

    2012-12-21

    Three regimes of relativistic beam - plasma interaction can in principle be reached at the ATF depending on the relative transverse and longitudinal size of the electron bunch when compared to the cold plasma collisionless skin depth c?{omega}{sub pe}: the plasma wakefield accelerator (PWFA), the self-modulation instability (SMI), and the current filamentation instability (CFI) regime. In addition, by choosing the bunch density, the linear, quasi-nonlinear and non linear regime of the PWFA can be reached. In the case of the two instabilities, the bunch density determines the growth rate and therefore the occurrence or not of the instability. We briefly describe these three regimes and outline results demonstrating that all these regime have or will be reached experimentally. We also outline planned and possible follow-on experiments.

  19. Ignition threshold for non-Maxwellian plasmas

    E-Print Network [OSTI]

    Hay, Michael J

    2015-01-01

    An optically thin $p$-$^{11}$B plasma loses more energy to bremsstrahlung than it gains from fusion reactions, unless the ion temperature can be elevated above the electron temperature. In thermal plasmas, the temperature differences required are possible in small Coulomb logarithm regimes, characterized by high density and low temperature. The minimum Lawson criterion for thermal $p$-$^{11}$B plasmas and the minimum $\\rho R$ required for ICF volume ignition are calculated. Ignition could be reached more easily if the fusion reactivity can be improved with nonthermal ion distributions. To establish an upper bound for this utility, we consider a monoenergetic beam with particle energy selected to maximize the beam- thermal reactivity. Channeling fusion alpha energy to maintain such a beam facilitates ignition at lower densities and $\\rho R$, improves reactivity at constant pressure, and could be used to remove helium ash. The gains realized with a beam thus establish an upper bound for the reductions in igniti...

  20. Negative plasma potential in a multidipole chamber with a dielectric coated plasma boundary

    SciTech Connect (OSTI)

    Sheehan, J. P.; Hershkowitz, Noah

    2012-05-15

    Negative plasma potentials with respect to a grounded wall that was coated with a dielectric have been achieved in an electropositive plasma confined by a multidipole device. A Langmuir probe was used to measure the density and temperatures of the bi-Maxwellian distribution electrons and an emissive probe was used to measure the plasma potential profile near the plasma boundary. For many discharge parameters, the potential profile was that of a typical electropositive sheath, but it was shifted negative due to negative charge accumulated on the plasma-surface boundary. A virtual cathode was observed near the boundary when the neutral pressure, primary electron energy, and/or discharge current were low ({approx}2 x 10{sup -4} Torr, {approx}60 eV, and 80 mA, respectively). The behavior of the sheath potential was shown to be consistent with that predicted by particle balance and a qualitative mechanism for wall charging is presented.

  1. Plasma sweeper. [Patents

    DOE Patents [OSTI]

    Motley, R.W.; Glanz, J.

    1982-10-25

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

  2. Shapes of Spectral Lines of Nonuniform Plasma of Electric Arc Discharge Between Copper Electrodes

    SciTech Connect (OSTI)

    Babich, Ida L.; Boretskij, Viacheslav F.; Veklich, Anatoly N.

    2007-09-28

    The radial profiles of the temperature and electron density in the plasma of the free burning electric arc between copper electrodes are studied by optical spectroscopy techniques. The electron density and the temperature in plasma as initial parameters were used in the calculation of the plasma composition in local thermodynamic equilibrium (LTE) assumption. We used the Saha's equation for copper, nitrogen and oxygen, dissociation equation for nitrogen and oxygen, the equation of plasma electrical neutrality and Dalton's law as well. So, it would be possible to determine the amounts of metal vapours in plasma.

  3. Cylindrical model of a helicon-generated plasma IEPC-2009-193

    E-Print Network [OSTI]

    Carlos III de Madrid, Universidad

    if the plasma density profile, n(r, z), and the absorbed power density Pa(r, z), are taken as input for the wave Electric Propulsion Conference, University of Michigan, Ann Arbor, Michigan, USA September 20­24, 2009. The energy absorbed from an helicon-wave ionizes the injected gas and heats the plasma. The magnetic field

  4. DEPOSITION OF FUEL PELLETS INJECTED INTO TOKAMAK PLASMAS Larry R. Baylor, T. C. Jernigan C. Hsieh

    E-Print Network [OSTI]

    DEPOSITION OF FUEL PELLETS INJECTED INTO TOKAMAK PLASMAS Larry R. Baylor, T. C. Jernigan C. Hsieh devices in a number of experiments to provide plasma fueling and density profile control. The mass deposition of these fuel pellets, defined as the change in density profile caused by the pellet, has been

  5. Response of the plasma to the size of an anode electrode biased near the plasma potential

    SciTech Connect (OSTI)

    Barnat, E. V.; Laity, G. R. [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States); Baalrud, S. D. [Department of Physics and Astronomy, University of Iowa, Iowa City, Iowa 52242 (United States)

    2014-10-15

    As the size of a positively biased electrode increases, the nature of the interface formed between the electrode and the host plasma undergoes a transition from an electron-rich structure (electron sheath) to an intermediate structure containing both ion and electron rich regions (double layer) and ultimately forms an electron-depleted structure (ion sheath). In this study, measurements are performed to further test how the size of an electron-collecting electrode impacts the plasma discharge the electrode is immersed in. This is accomplished using a segmented disk electrode in which individual segments are individually biased to change the effective surface area of the anode. Measurements of bulk plasma parameters such as the collected current density, plasma potential, electron density, electron temperature and optical emission are made as both the size and the bias placed on the electrode are varied. Abrupt transitions in the plasma parameters resulting from changing the electrode surface area are identified in both argon and helium discharges and are compared to the interface transitions predicted by global current balance [S. D. Baalrud, N. Hershkowitz, and B. Longmier, Phys. Plasmas 14, 042109 (2007)]. While the size-dependent transitions in argon agree, the size-dependent transitions observed in helium systematically occur at lower electrode sizes than those nominally derived from prediction. The discrepancy in helium is anticipated to be caused by the finite size of the interface that increases the effective area offered to the plasma for electron loss to the electrode.

  6. Time-Resonant Tokamak Plasma Edge Instabilities?

    E-Print Network [OSTI]

    Webster, A J; Calderon, F A; Chapman, S C; Delabie, E; Dodt, D; Felton, R; Todd, T N; Maviglia, F; Morris, J; Riccardo, V; Alper, B; Brezinsek, S; Coad, P; Likonen, J; Rubel, M; Contributors, JET EFDA

    2013-01-01

    For a two week period during the Joint European Torus (JET) 2012 experimental campaign, the same high confinement plasma was repeated 151 times. The dataset was analysed to produce a probability density function (pdf) for the waiting times between edge-localised plasma instabilities ("ELMS"). The result was entirely unexpected. Instead of a smooth single peaked pdf, a succession of 4-5 sharp maxima and minima uniformly separated by 7-8 millisecond intervals was found. Here we explore the causes of this newly observed phenomenon, and conclude that it is either due to a self-organised plasma phenomenon or an interaction between the plasma and a real-time control system. If the maxima are a result of "resonant" frequencies at which ELMs can be triggered more easily, then future ELM control techniques can, and probably will, use them. Either way, these results demand a deeper understanding of the ELMing process.

  7. Fast wave evanescence in filamentary boundary plasmas

    SciTech Connect (OSTI)

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

    2014-02-15

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

  8. Magnetohydrodynamics in Tokamak Reactors and its Effect on Plasma Density 

    E-Print Network [OSTI]

    Morelli, Franco

    2011-12-01

    that the process by which the sun produces its energy is via nuclear fusion. The heavy element, Uranium- 235, found in most nuclear reactors around the world was produced during a stars supernova. To date, nuclear fission is the only wide scale use of nuclear... be clean as well as safe if it is to be widely accepted. Clearly, the problems associated with nuclear fission go without saying. What is needed is a source of nuclear energy that is clean and relatively safe. There are only two possibilities when...

  9. Using Radio Waves to Control Fusion Plasma Density

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-Inspired SolarAbout /Two0 - 19PortalStatusUserUserHomeUsing RunningUsing

  10. Internal field, density & temperature measurements in MTF plasmas using

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing(Journalspectroscopy of aerosols in high-temperature applications.cells: The

  11. Internal field, density & temperature measurements in MTF plasmas using

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing(Journalspectroscopy of aerosols in high-temperature applications.cells: ThePulsed

  12. High Energy Density Laboratory Plasmas Program | National Nuclear Security

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformation CurrentHenry Bellamy, Ph.D. Title: Professor - Research

  13. High Energy Density Laboratory Plasmas | National Nuclear Security

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformation CurrentHenry Bellamy, Ph.D. Title: Professor - ResearchAdministration |

  14. Study on the effect of target on plasma parameters of magnetron sputtering discharge plasma

    SciTech Connect (OSTI)

    Saikia, P.; Kakati, B.; Saikia, B. K. [Centre of Plasma Physics, Institute for Plasma Research, Nazirakhat, Sonapur-782 402, Kamrup, Assam (India)] [Centre of Plasma Physics, Institute for Plasma Research, Nazirakhat, Sonapur-782 402, Kamrup, Assam (India)

    2013-10-15

    In this study, the effect of magnetron target on different plasma parameters of Argon/Hydrogen (Ar - H{sub 2}) direct current (DC) magnetron discharge is examined. Here, Copper (Cu) and Chromium (Cr) are used as magnetron targets. The value of plasma parameters such as electron temperature (kT{sub e}), electron density (N{sub e}), ion density (N{sub i}), degree of ionization of Ar, and degree of dissociation of H{sub 2} for both the target are studied as a function of input power and hydrogen content in the discharge. The plasma parameters are determined by using Langmuir probe and Optical emission spectroscopy. On the basis of the different reactions in the gas phase, the variation of plasma parameters and sputtering rate are explained. The obtained results show that electron and ion density decline with gradual addition of Hydrogen in the discharge and increase with rising input power. It brings significant changes on the degree of ionization of Ar and dissociation of H{sub 2}. The enhanced value of electron density (N{sub e}), ion density (N{sub i}), degree of Ionization of Ar, and degree of dissociation of H{sub 2} for Cr compared to Cu target is explained on the basis of it's higher Ion Induced Secondary Electron Emission Coefficient (ISEE) value.

  15. Strongly Interacting Matter at High Energy Density

    E-Print Network [OSTI]

    Larry McLerran

    2008-12-08

    This lecture concerns the properties of strongly interacting matter (which is described by Quantum Chromodynamics) at very high energy density. I review the properties of matter at high temperature, discussing the deconfinement phase transition . At high baryon density and low temperature, large $N_c$ arguments are developed which suggest that high baryonic density matter is a third form of matter, Quarkyonic Matter, that is distinct from confined hadronic matter and deconfined matter. I finally discuss the Color Glass Condensate which controls the high energy limit of QCD, and forms the low x part of a hadron wavefunction. The Glasma is introduced as matter formed by the Color Glass Condensate which eventually thermalizes into a Quark Gluon Plasma.

  16. Effect of plasma parameters on growth and field emission properties of spherical carbon nanotube tip

    SciTech Connect (OSTI)

    Sharma, Suresh C.; Tewari, Aarti

    2011-06-15

    The effect of plasma parameters (e.g., electron density and temperature, ion density and temperature, neutral atom density and temperature) on the growth (without a catalyst), structure, and field emission properties of a spherical carbon nanotube (CNT) tip has been theoretically investigated. A theoretical model of charge neutrality, including the kinetics of electrons, positively charged ions, and neutral atoms and the energy balance of the various species in plasma, has been developed. Numerical calculations of the radius of the spherical CNT tip for different CNT number densities and plasma parameters have been carried out for the typical glow discharge plasma parameters. It is found that upon an increase in the CNT number density and plasma parameters, the radius of the spherical CNT tip decreases, and consequently the field emission factor for the spherical CNT tip increases.

  17. Cold atmospheric plasma in cancer therapy

    SciTech Connect (OSTI)

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

    2013-05-15

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

  18. Large area atmospheric-pressure plasma jet

    DOE Patents [OSTI]

    Selwyn, Gary S. (Los Alamos, NM); Henins, Ivars (Los Alamos, NM); Babayan, Steve E. (Huntington Beach, CA); Hicks, Robert F. (Los Angeles, CA)

    2001-01-01

    Large area atmospheric-pressure plasma jet. A plasma discharge that can be operated at atmospheric pressure and near room temperature using 13.56 MHz rf power is described. Unlike plasma torches, the discharge produces a gas-phase effluent no hotter than 250.degree. C. at an applied power of about 300 W, and shows distinct non-thermal characteristics. In the simplest design, two planar, parallel electrodes are employed to generate a plasma in the volume therebetween. A "jet" of long-lived metastable and reactive species that are capable of rapidly cleaning or etching metals and other materials is generated which extends up to 8 in. beyond the open end of the electrodes. Films and coatings may also be removed by these species. Arcing is prevented in the apparatus by using gas mixtures containing He, which limits ionization, by using high flow velocities, and by properly spacing the rf-powered electrode. Because of the atmospheric pressure operation, there is a negligible density of ions surviving for a sufficiently long distance beyond the active plasma discharge to bombard a workpiece, unlike the situation for low-pressure plasma sources and conventional plasma processing methods.

  19. I. H. Tan1, M. Ueda1, R. S. Dallaqua1, J. O. Rossi1, A. F. Beloto2 Instituto Nacional de Pesquisas Espaciais 1Laboratrio Associado de Plasma

    E-Print Network [OSTI]

    in 60µs In metal plasmas generated by vacuum arcs: Magnetic field increases plasma density by two orders plasmas) · Thermal cycling · Adhesion test Objectives #12;Vacuum Arc Plasmas: HV trigger: arc initiation minimized by orienting samples parallel to plasma stream #12;Vacuum arc: Al cathode Tungsten grid anode HV

  20. Submitted IEEE Trans. Plasma Science Shvets Fisch

    E-Print Network [OSTI]

    accelerator (CBA). CBA impor- tant features: the required intensities of colliding laser pulses much smaller excitation of the enhanced wake analogous latter. addition, demon- strate CBA can as a compressor

  1. Burning Plasma Science: The Challenge and Opportunity

    E-Print Network [OSTI]

    Dominated) Q ~ 1 Q ~ 0.01 Q ~ 0.00001 Q ~ 0.001 Q ~ 0.01 NIF LMJ NIF LMJ T-3 1965 T-3 1968 Laser 1996 Direct

  2. Robotics Science & Technology for Burning Plasma Experiments

    E-Print Network [OSTI]

    components for refurbishment. · Remote tools for specialized applications such as lip-seal cutting vessel sectors, and hot-cell refurbishment of first-wall components. Items in italics are first order

  3. 2012 Science Bowls | Princeton Plasma Physics Lab

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-InspiredAtmosphericdevicesPPONe β+-DecayUpgradeDepartment of2

  4. Surface science | Princeton Plasma Physics Lab

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-Inspired Solar Fuel Production 1: TotalofSupplySurface Soil Surface Soil

  5. About Science Education | Princeton Plasma Physics Lab

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room News Publications Traditional Knowledge KiosksAbout Us Contact3/2014 SEARCH SRNL GOAbout

  6. Science Education | Princeton Plasma Physics Lab

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory ofDidDevelopment Top LDRDUniversitySchedules PrintNIF About Blog Programs

  7. Princeton Plasma Physics Lab - Science literacy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass mapSpeedingProgram GuidelinesThousandnstx-u The Nationalsystem-design

  8. Princeton Plasma Physics Lab - Surface science

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass mapSpeedingProgram GuidelinesThousandnstx-u The

  9. Science Education Blog | Princeton Plasma Physics Lab

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation ofAlbuquerque| Stanford SynchrotronVideo-Contest December 17, 2015 Join us on

  10. Science Education Lab | Princeton Plasma Physics Lab

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation ofAlbuquerque| Stanford SynchrotronVideo-Contest December 17, 2015 Join us

  11. Science Education Programs | Princeton Plasma Physics Lab

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation ofAlbuquerque| Stanford SynchrotronVideo-Contest December 17, 2015 Join

  12. Science Education | Princeton Plasma Physics Lab

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation ofAlbuquerque| Stanford SynchrotronVideo-Contest December 17, 2015 JoinUpcoming

  13. Positron plasma control techniques for the production of cold antihydrogen

    SciTech Connect (OSTI)

    Funakoshi, R.; Hayano, R. S. [Department of Physics, University of Tokyo, Tokyo 113-0033 (Japan); Amoretti, M.; Macri, M.; Testera, G.; Variola, A. [Istituto Nazionale di Fisica Nucleare, Sezione di Genova, 16146 Genova (Italy); Bonomi, G. [Dipartimento di Ingegneria Meccanica, Universita di Brescia, 25123 Brescia (Italy); Dipartimento di Fisica Nucleare e Teorica, Universita di Pavia, 27100 Pavia (Italy); Bowe, P. D.; Hangst, J. S.; Madsen, N. [Department of Physics and Astronomy, University of Aarhus, 8000 Aarhus C (Denmark); Canali, C.; Carraro, C.; Lagomarsino, V.; Manuzio, G. [Istituto Nazionale di Fisica Nucleare, Sezione di Genova, 16146 Genova (Italy); Dipartimento di Fisica, Universita di Genova, 16146 Genova (Italy); Cesar, C. L. [Instituto de Fisica, Universidade do Brasil, Cx Postal 68528, Rio de Janeiro 21941-972 (Brazil); Charlton, M.; Joergensen, L. V.; Mitchard, D.; Werf, D. P. van der [Department of Physics, University of Wales Swansea, Swansea SA2 8PP (United Kingdom); Doser, M. [PH Department, CERN, 1211 Geneva 23 (Switzerland)] (and others)

    2007-07-15

    An observation of a clear dependence of antihydrogen production on positron plasma shapes is reported. For this purpose a plasma control method has been developed combining the plasma rotating-wall technique with a mode diagnostic system. With the help of real-time and nondestructive observations, the rotating-wall parameters have been optimized. The positron plasma can be manipulated into a wide range of shapes (aspect ratio 6.5{<=}{alpha} < or approx. 80) and densities (1.5x10{sup 8}{<=}n < or approx. 7x10{sup 9} cm{sup -3}) within a short duration (25 s) compatible with the ATHENA antihydrogen production cycle.

  14. Linear and nonlinear wave propagation in weakly relativistic quantum plasmas

    SciTech Connect (OSTI)

    Stefan, Martin; Brodin, Gert [Department of Physics, Umea University, SE-901 87 Umea (Sweden)

    2013-01-15

    We consider a recently derived kinetic model for weakly relativistic quantum plasmas. We find that that the effects of spin-orbit interaction and Thomas precession may alter the linear dispersion relation for a magnetized plasma in case of high plasma densities and/or strong magnetic fields. Furthermore, the ponderomotive force induced by an electromagnetic pulse is studied for an unmagnetized plasma. It turns out that for this case the spin-orbit interaction always gives a significant contribution to the quantum part of the ponderomotive force.

  15. Dense Metal Plasma in a Solenoid for Ion Beam Neutralization

    SciTech Connect (OSTI)

    Anders, Andre; Kauffeldt, Marina; Oks, Efim M.; Roy, Prabir K.

    2010-10-30

    Space-charge neutralization is required to compress and focus a pulsed, high-current ion beam on a target for warm dense matter physics or heavy ion fusion experiments. We described approaches to produce dense plasma in and near the final focusing solenoid through which the ion beam travels, thereby providing an opportunity for the beam to acquire the necessary space-charge compensating electrons. Among the options are plasma injection from pulsed vacuum arc sources located outside the solenoid, and using a high current (> 4 kA) pulsed vacuum arc plasma from a ring cathode near the edge of the solenoid. The plasma distribution is characterized by photographic means, by an array of movable Langmuir probes, by a small single probe, and by evaluating Stark broadening of the Balmer H beta spectral line. In the main approach described here, the plasma is produced at several cathode spots distributed azimuthally on the ring cathode. It is shown that the plasma is essentially hollow, as determined by the structure of the magnetic field, though the plasma density exceeds 1014 cm-3 in practically all zones of the solenoid volume if the ring electrode is placed a few centimeters off the center of the solenoid. The plasma is non-uniform and fluctuating, however, since its density exceeds the ion beam density it is believed that this approach could provide a practical solution to the space charge neutralization challenge.

  16. Bright X-ray source from a laser-driven micro-plasma-waveguide

    E-Print Network [OSTI]

    Yi, Longqing; Thanh, Phuc Luu; Shen, Baifei

    2015-01-01

    Bright tunable x-ray sources have a number of applications in basic science, medicine and industry. The most powerful sources are synchrotrons, where relativistic electrons are circling in giant storage rings. In parallel, compact laser-plasma x-ray sources are being developed. Owing to the rapid progress in laser technology, very high-contrast femtosecond laser pulses of relativistic intensities become available. These pulses allow for interaction with micro-structured solid-density plasma without destroying the structure by parasitic pre-pulses. The high-contrast laser pulses as well as the manufacturing of materials at micro- and nano-scales open a new realm of possibilities for laser interaction with photonic materials at the relativistic intensities. Here we demonstrate, via numerical simulations, that when coupling with a readily available 1.8 Joule laser, a micro-plasma-waveguide (MPW) may serve as a novel compact x-ray source. Electrons are extracted from the walls by the laser field and form a dense ...

  17. UFA Technical Policy on Burning Plasma A burning plasma (BP) experiment would greatly strengthen the US fusion energy

    E-Print Network [OSTI]

    the US fusion energy sciences program. The TFTR and JET experiments have produced reactor like plasmas advances towards practical fusion energy. The UFA supports the exploration of potential BP experiments and advocates that this important next step be pursued by the U S fusion energy sciences program. The main focus

  18. JKS2004-Aug25-27/04 ST Science & Fusion Martin Peng

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    plasma particles and waves interact? · How do hot plasmas interact with walls? · How to supply magnetic constant ( = pe 2/ce 2 ~ 50) How do plasmas interact with walls? · Large mirror ratio in edge B field (f Spherical Tokamak Plasma Science & Fusion Energy Supported by Columbia U Comp-X General Atomics INEL Johns

  19. Nonlinear plasma wave in magnetized plasmas

    SciTech Connect (OSTI)

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

    2013-08-15

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

  20. Determination of the transient electron temperature in a femtosecond-laser-induced air plasma filament

    SciTech Connect (OSTI)

    Sun Zhanliang; Chen Jinhai; Rudolph, Wolfgang

    2011-04-15

    The transient electron temperature in a weakly ionized femtosecond-laser-produced air plasma filament was determined from optical absorption and diffraction experiments. The electron temperature and plasma density decay on similar time scales of a few hundred picoseconds. Comparison with plasma theory reveals the importance of inelastic collisions that lead to energy transfer to vibrational degrees of freedom of air molecules during the plasma cooling.