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1

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...

2

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

E-Print Network [OSTI]

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 ...

Ellsworth, Jennifer L

2010-01-01T23:59:59.000Z

3

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

SciTech Connect (OSTI)

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.

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)

2014-02-15T23:59:59.000Z

4

Princeton Plasma Physics Laboratory  

SciTech Connect (OSTI)

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.

Not Available

1990-01-01T23:59:59.000Z

5

Measuring the plasma density of a ferroelectric plasma source in an expanding plasma  

E-Print Network [OSTI]

Measuring the plasma density of a ferroelectric plasma source in an expanding plasma A. Dunaevsky and N. J. Fisch Princeton Plasma Physics Laboratory, Princeton University, P.O. Box 451, Princeton, New temperature at the surface of a ferroelectric plasma source were deduced from floating probe measurements

6

Princeton Plasma Physics Laboratory:  

SciTech Connect (OSTI)

This paper discusses progress on experiments at the Princeton Plasma Physics Laboratory. The projects and areas discussed are: Principal Parameters Achieved in Experimental Devices, Tokamak Fusion Test Reactor, Princeton Large Torus, Princeton Beta Experiment, S-1 Spheromak, Current-Drive Experiment, X-ray Laser Studies, Theoretical Division, Tokamak Modeling, Spacecraft Glow Experiment, Compact Ignition Tokamak, Engineering Department, Project Planning and Safety Office, Quality Assurance and Reliability, and Administrative Operations.

Phillips, C.A. (ed.)

1986-01-01T23:59:59.000Z

7

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

SciTech Connect (OSTI)

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.

Shvets, Gennady

2014-05-09T23:59:59.000Z

8

Exploration of Plasma Jets Approach to High Energy Density Physics  

SciTech Connect (OSTI)

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.

Chen, Chiping [Massachusetts Institute of Technology

2013-08-26T23:59:59.000Z

9

High Energy Density Laboratory Plasmas  

E-Print Network [OSTI]

faciliBes 1st users of MECI in FY13 Recognize common interests NNSA/FES Compliment NNSA investments Stability ­ investments in HEDLP: people, departments

10

MIT Lincoln Laboratory Plasma and Ions-1  

E-Print Network [OSTI]

them anions · Fire, lightning, fluorescent lamps, and the Sun and stars all contain plasma ­ In fact include fluorescent lamps, neon signs, plasma globes, plasma TVs ­ They easily form at room temperature lightning carbon arc nuclear blast #12;MIT Lincoln LaboratoryPlasma and Ions-4 A. Siegel 5/12/07 How Does

Wurtman, Richard

11

Betatron radiation from density tailored plasmas  

E-Print Network [OSTI]

Betatron radiation from density tailored plasmas K. Tathe resulting betatron radiation spectrum can therefore bepro?le, the betatron radiation emitted by theses electrons

Ta Phuoc, Kim

2010-01-01T23:59:59.000Z

12

Princeton Plasma Physics Laboratory Honors Three Researchers...  

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

Princeton Plasma Physics Laboratory Honors Three Researchers March 12, 2012 Tweet Widget Google Plus One Share on Facebook Gallery: Kenneth Hill received the Kaul Prize for...

13

The temperature dependence of equilibrium plasma density  

E-Print Network [OSTI]

Temperature dependence of an electron-nuclear plasma equilibrium density is considered basing on known approaches, which are given in (1)(2). It is shown that at a very high temperature, which is characteristic for a star interior, the equilibrium plasma density is almost constant and equals approximately to $10^{25}$ particles per $cm^3$. At a relatively low temperature, which is characteristic for star surface, the equilibrium plasma density is in several orders lower and depends on temperature as $T^{3/2}$.

B. V. Vasiliev

2002-03-17T23:59:59.000Z

14

Laboratory Director PRINCETON PLASMA PHYSICS LABORATORY  

E-Print Network [OSTI]

.C. Zarnstorff Deputy Director for Operations A.B. Cohen Laboratory Management Council Research Council Associate Diagnostics D.W. Johnson Electrical Systems C. Neumeyer Lab Astrophysics M. Yamada, H. Ji Projects: MRX, MRI Science Education A. Post-Zwicker Quality Assurance J.A. Malsbury Tech. Transfer Patents & Publications L

Princeton Plasma Physics Laboratory

15

Exploiting Laboratory and Heliophysics Plasma Synergies  

E-Print Network [OSTI]

Recent advances in space-based heliospheric observations, laboratory experimentation, and plasma simulation codes are creating an exciting new cross-disciplinary opportunity for understanding fast energy release and transport ...

Dahlburg, Jill

16

Princeton Plasma Physics Laboratory NSTX Experimental Proposal  

E-Print Network [OSTI]

and that this may effect the energy confinement time as well as provide current drive. Of course, other effects mayPrinceton Plasma Physics Laboratory NSTX Experimental Proposal Title: CHI into an ohmic discharge

Princeton Plasma Physics Laboratory

17

Princeton Plasma Physics Laboratory NSTX Experimental Proposal  

E-Print Network [OSTI]

Princeton Plasma Physics Laboratory NSTX Experimental Proposal Title: Dependence of ELM size Thermonuclear Experimental Reactor (ITER) have yielded a pedestal energy loss fraction between 5% and 20 with resonant magnetic perturbations2 or by access to small ELM regimes. Fig. 1 from reference1 , where

Princeton Plasma Physics Laboratory

18

Princeton Plasma Physics Laboratory NSTX Experimental Proposal  

E-Print Network [OSTI]

Princeton Plasma Physics Laboratory NSTX Experimental Proposal Title: Dependence of ELM size Projections1 of the energy loss from Type I ELMs for the International Thermonuclear Experimental Reactor perturbations2 or by access to small ELM regimes. Fig. 1 from reference1 , where extrapolation to ITER is done

Princeton Plasma Physics Laboratory

19

ASSOCIATED LABORATORY PLASMA PHYSICS AND ENGINEERING  

E-Print Network [OSTI]

and approved by the "Consultative Committee for the Specific Research and Training Programme on Nuclear Energy in the frame of the so-called Broader Approach to Fusion Energy; · Collaboration on Nuclear FusionASSOCIATED LABORATORY ON PLASMA PHYSICS AND ENGINEERING Centro de Fusão Nuclear Centro de Física

Lisboa, Universidade Técnica de

20

Ris National Laboratory Optics and Plasma Reserch Department  

E-Print Network [OSTI]

; Frédéric J. G. Cuisinier Optics and Plasma Research Department, Risø National Laboratory, DK-4000 Roskilde and Henrik C. Pedersen Optics and Plasma Research Department, Risø National Laboratory, DK-4000 Roskilde

Note: This page contains sample records for the topic "density laboratory plasmas" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Ris National Laboratory Optics and Plasma Reserch Department  

E-Print Network [OSTI]

, Anders Bjarklev, Peter E. Andersen Risø National Laboratory, Optics and Plasma Research Department, DK amplifier Frederik D. Nielsen and Lars Thrane Risø National Laboratory, Optics and Plasma Research. Lyngby, Denmark Peter E. Andersen (corresponding author) Risø National Laboratory, Optics and Plasma

22

Ris National Laboratory Optics and Plasma Reserch Department  

E-Print Network [OSTI]

and Plasma Research Department, Risø National Laboratory, Frederiksborgvej 399, 4000 Roskilde, Denmark S. Sørensena Optics and Plasma Research Department, Risø National Laboratory, Frederiksborgvej 399 and Plasma Research Department, Risø National Laboratory, Frederiksborgvej 399, 4000 Roskilde, Denmark

23

Ris National Laboratory Optics and Plasma Reserch Department  

E-Print Network [OSTI]

and Plasma Research, Risø National Laboratory, DK-4000 Roskilde,Denmark;2Coherentia CNR-INFM and Dipartimento statement Copyright 2007 Springer Doi 1Department of Optics and Plasma Research, Risø National Laboratory , Salvatore Amoruso2 and James G. Lunney3 1 Department of Optics and Plasma Research, Risø National Laboratory

24

Ris National Laboratory Optics and Plasma Research Department  

E-Print Network [OSTI]

Risø National Laboratory Postprint Optics and Plasma Research Department Year: 2006 Paper: www and Plasma Research, OPL-128 Risø DK-4000 Roskilde, Denmark Required publisher statement Copyright (2005 Association EURATOM-Risø National Laboratory Optics and Plasma Research, OPL-128 Risø DK-4000 Roskilde

25

Ris National Laboratory Optics and Plasma Reserch Department  

E-Print Network [OSTI]

Optics and Plasma Research Department, Risø National Laboratory Required publisher statement Copyright: Optics and Plasma Research Department Division: Risoe National National Laboratory Address: P.O. Box 49Name: R. Suffix: Organization: Optics and Plasma Research Department Division: Risoe National National

26

Ris National Laboratory DTU Optics and Plasma Research Department  

E-Print Network [OSTI]

Risø National Laboratory DTU Postprint Optics and Plasma Research Department 2007 Paper: www (MAPLE) K Rodrigo1,2, J Schou1#, B Toftmann1 and R Pedrys2 1 Department of Optics and Plasma Research Department of Optics and Plasma Research, Risø National Laboratory, DK-4000 Roskilde, Denmark 2 Institute

27

Statement of Harold P. Furth Director, Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

: .. _I Statement of Harold P. Furth Director, Princeton Plasma Physics Laboratory before base.) The new plasma-physics phenomena expected in burning plasmas are mainly due to the presence dense, very-hot-ion plasma regimes that have been achieved in TFTR are particularly well suited

28

Plasma and Technology Programme National Laboratory for Sustainable Energy  

E-Print Network [OSTI]

1 Plasma and Technology Programme National Laboratory for Sustainable Energy Technical University METHODS OF OZONE GENERATION BY MICRO-PLASMA CONCEPT Authors A. Fateev, A. Chiper, W. Chen and E. Stamate-1-6365 project devoted to plasma-assisted DeNOx. Ozone is as a key agent in plasma NOx reduction because

29

Wavefront-sensor-based electron density measurements for laser-plasma accelerators  

E-Print Network [OSTI]

Principles of Plasma Diagnostics, 2nd ed. (CambridgeSchematic of the plasma density diagnostics. When using theshot-to-shot plasma-density diagnostics. PACS numbers:

Plateau, Guillaume

2010-01-01T23:59:59.000Z

30

Relativistic plasma nanophotonics for ultrahigh energy density physics  

E-Print Network [OSTI]

Relativistic plasma nanophotonics for ultrahigh energy density physics Michael A. Purvis1 volumetrically heat dense matter into a new ultrahot plasma regime. Electron densities nearly 100 times greater) and gigabar press- ures only exceeded in the central hot spot of highly compressed thermonuclear fusion

Rocca, Jorge J.

31

Proposed method for high-speed plasma density measurement in proton-driven plasma wakefield acceleration  

SciTech Connect (OSTI)

Recently a proton-bunch-driven plasma wakefield acceleration experiment using the CERN-SPS beam was proposed. Different types of plasma cells are under study, especially laser ionization, plasma discharge, and helicon sources. One of the key parameters is the spatial uniformity of the plasma density profile along the cell that has to be within < 1% of the nominal density (6 Multiplication-Sign 10{sup 14} cm{sup -3}). Here a setup based on a photomixing concept is proposed to measure the plasma cut-off frequency and determine the plasma density.

Tarkeshian, R.; Reimann, O.; Muggli, P. [Max-Planck-Institut fuer Physik, 80805 Munich (Germany)

2012-12-21T23:59:59.000Z

32

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

SciTech Connect (OSTI)

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.

Schroeder, C. B.; Esarey, E.; Leemans, W. P. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)

2012-12-21T23:59:59.000Z

33

Local thermodynamic equilibrium in rapidly heated high energy density plasmas  

SciTech Connect (OSTI)

Emission spectra and the dynamics of high energy density plasmas created by optical and Free Electron Lasers (FELs) depend on the populations of atomic levels. Calculations of plasma emission and ionization may be simplified by assuming Local Thermodynamic Equilibrium (LTE), where populations are given by the Saha-Boltzmann equation. LTE can be achieved at high densities when collisional processes are much more significant than radiative processes, but may not be valid if plasma conditions change rapidly. A collisional-radiative model has been used to calculate the times taken by carbon and iron plasmas to reach LTE at varying densities and heating rates. The effect of different energy deposition methods, as well as Ionization Potential Depression are explored. This work shows regimes in rapidly changing plasmas, such as those created by optical lasers and FELs, where the use of LTE is justified, because timescales for plasma changes are significantly longer than the times needed to achieve an LTE ionization balance.

Aslanyan, V.; Tallents, G. J. [York Plasma Institute, Department of Physics, University of York, Heslington, York YO10 5DD (United Kingdom)

2014-06-15T23:59:59.000Z

34

Ducted kinetic Alfven waves in plasma with steep density gradients  

SciTech Connect (OSTI)

Given their high plasma density (n {approx} 10{sup 13} cm{sup -3}), it is theoretically possible to excite Alfven waves in a conventional, moderate length (L {approx} 2 m) helicon plasma source. However, helicon plasmas are decidedly inhomogeneous, having a steep radial density gradient, and typically have a significant background neutral pressure. The inhomogeneity introduces regions of kinetic and inertial Alfven wave propagation. Ion-neutral and electron-neutral collisions alter the Alfven wave dispersion characteristics. Here, we present the measurements of propagating kinetic Alfven waves in helium helicon plasma. The measured wave dispersion is well fit with a kinetic model that includes the effects of ion-neutral damping and that assumes the high density plasma core defines the radial extent of the wave propagation region. The measured wave amplitude versus plasma radius is consistent with the pile up of wave magnetic energy at the boundary between the kinetic and inertial regime regions.

Houshmandyar, Saeid [Solar Observatory Department, Prairie View A and M University, Prairie View, Texas 77446 (United States); Department of Physics, West Virginia University, Morgantown, West Virginia 26506-6315 (United States); Scime, Earl E. [Department of Physics, West Virginia University, Morgantown, West Virginia 26506-6315 (United States)

2011-11-15T23:59:59.000Z

35

Atomic processes in high-density plasmas  

SciTech Connect (OSTI)

This review covers dense atomic plasmas such as that produced in inertial confinement fusion. The target implosion physics along with the associated atomic physics, i.e., free electron collision phenomena, electron states I, electron states II, and nonequilibrium plasma states are described. (MOW)

More, R.M.

1982-12-21T23:59:59.000Z

36

Ames Laboratory Plasma Spray (ALPS) Facility | The Ames Laboratory  

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

that are very reactive and have high melting temperatures. HVOF and Plasma spray guns and an atmospheric chamber are available. Following the early development of numerous...

37

Laboratory Study Of Magnetic Reconnection With A Density Asymmetry Across The Current Sheet  

SciTech Connect (OSTI)

The effects of an upstream density asymmetry on magnetic reconnection are studied systematically in a laboratory plasma. Despite a significant upstream density asymmetry of up to 10, the reconnecting magnetic field pro file is not signifi cantly changed. On the other hand, the out-of-plane magnetic field profile is considerably modified; it is almost bipolar in structure with the density asymmetry, as compared to the quadrupolar structure in the symmetric configuration. The in-plane ion flow pattern and the electrostatic potential pro file are also affected by the density asymmetry. Strong bulk electron heating is observed near the low-density-side separatrix together with electromagnetic fluctuations in the lower hybrid frequency range. The dependence of the ion outflow and reconnection electric field on the density asymmetry is measured and compared with theoretical expectations.

Yoo, Joseph; Yamada, Massaaki; Ji, Hantao; Meyers,, Clayton E.; Jara-Almonte,; Chen, Li-Jen

2014-04-18T23:59:59.000Z

38

Measurements of neutral helium density in helicon plasmas  

SciTech Connect (OSTI)

Laser-induced-fluorescence (LIF) is used to measure the density of helium atoms in a helicon plasma source. For a pump wavelength of 587.725 nm (vacuum) and laser injection along the magnetic field, the LIF signal exhibits a signal decrease at the Doppler shifted central wavelength. The drop in signal results from the finite optical depth of the plasma and the magnitude of the decrease is proportional to the density of excited state neutral atoms. Using Langmuir probe measurements of plasma density and electron temperature and a collisional-radiative model, the absolute ground state neutral density is calculated from the optical depth measurements. Optimal plasma performance, i.e., the largest neutral depletion on the axis of the system, is observed for antenna frequencies of 13.0 and 13.5 MHz and magnetic field strengths of 550-600 G.

Houshmandyar, Saeid; Sears, Stephanie H.; Thakur, Saikat Chakraborty; Carr, Jerry Jr.; Galante, Matthew E.; Scime, Earl E. [Department of Physics, West Virginia University, Morgantown, West Virginia 26506-6315 (United States)

2010-10-15T23:59:59.000Z

39

PRINCETON PLASMA PHYSICS LABORATORY (PPPL) ANNUAL SITE ENVIRONMENTAL REPORT  

E-Print Network [OSTI]

;.............................................................................................................. Page 4.4 Environmental Impact Statements and Environmental Assessments ........................ 26 4#12;#12;PRINCETON PLASMA PHYSICS LABORATORY (PPPL) ANNUAL SITE ENVIRONMENTAL REPORT FOR CALENDAR.1 Environmental Compliance....................................................................... 8 3

40

PRINCETON PLASMA PHYSICS LABORATORY (PPPL) ANNUAL SITE ENVIRONMENTAL REPORT  

E-Print Network [OSTI]

3.1.3 National Environmental Policy Act (NEPA#12;#12;PRINCETON PLASMA PHYSICS LABORATORY (PPPL) ANNUAL SITE ENVIRONMENTAL REPORT FOR CALENDAR 1996 Site Environmental Report Table of Contents Page 1.0 EXECUTIVE SUMMARY

Note: This page contains sample records for the topic "density laboratory plasmas" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Absorption spectroscopy of a laboratory photoionized plasma experiment at Z  

SciTech Connect (OSTI)

The Z facility at the Sandia National Laboratories is the most energetic terrestrial source of X-rays and provides an opportunity to produce photoionized plasmas in a relatively well characterised radiation environment. We use detailed atomic-kinetic and spectral simulations to analyze the absorption spectra of a photoionized neon plasma driven by the x-ray flux from a z-pinch. The broadband x-ray flux both photoionizes and backlights the plasma. In particular, we focus on extracting the charge state distribution of the plasma and the characteristics of the radiation field driving the plasma in order to estimate the ionisation parameter.

Hall, I. M.; Durmaz, T.; Mancini, R. C. [Physics Department, University of Nevada, Reno, Nevada 89557 (United States)] [Physics Department, University of Nevada, Reno, Nevada 89557 (United States); Bailey, J. E.; Rochau, G. A. [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)] [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States); Golovkin, I. E.; MacFarlane, J. J. [Prism Computational Sciences, Madison, Wisconsin 53711 (United States)] [Prism Computational Sciences, Madison, Wisconsin 53711 (United States)

2014-03-15T23:59:59.000Z

42

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

SciTech Connect (OSTI)

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.

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)

2014-04-15T23:59:59.000Z

43

Princeton Plasma Physics Laboratory NSTX Experimental Proposal  

E-Print Network [OSTI]

is to apply small oscillations in the plasma vertical position, in order to trigger ELMs. The vertical oscillations will be generated in one of two ways i) by requesting rapid variations in the plasma vertical position, or ii) explicitly adding a "kick" voltage to the PF-3 coil, and then allowing the vertical

Princeton Plasma Physics Laboratory

44

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

E-Print Network [OSTI]

high temperature plasma diagnostics used to study high en-high temperature plasma diagnostic. Plasma bremsstrahlungand J Ärje. Plasma breakdown diagnostics with the biased

Noland, Jonathan David

2011-01-01T23:59:59.000Z

45

Princeton Plasma Physics Laboratory NSTX Experimental Proposal  

E-Print Network [OSTI]

in a "fixed wall" device is key for management of plasma-wall (i.e., divertor) interactions. In particular-H transition. The early times after this transition being generally blob-less. The proposed experiment intends

Princeton Plasma Physics Laboratory

46

Simulating Magnetized Laboratory Plasmas with Smoothed Particle Hydrodynamics  

SciTech Connect (OSTI)

The creation of plasmas in the laboratory continues to generate excitement in the physics community. Despite the best efforts of the intrepid plasma diagnostics community, the dynamics of these plasmas remains a difficult challenge to both the theorist and the experimentalist. This dissertation describes the simulation of strongly magnetized laboratory plasmas with Smoothed Particle Hydrodynamics (SPH), a method born of astrophysics but gaining broad support in the engineering community. We describe the mathematical formulation that best characterizes a strongly magnetized plasma under our circumstances of interest, and we review the SPH method and its application to astrophysical plasmas based on research by Phillips [1], Buerve [2], and Price and Monaghan [3]. Some modifications and extensions to this method are necessary to simulate terrestrial plasmas, such as a treatment of magnetic diffusion based on work by Brookshaw [4] and by Atluri [5]; we describe these changes as we turn our attention toward laboratory experiments. Test problems that verify the method are provided throughout the discussion. Finally, we apply our method to the compression of a magnetized plasma performed by the Compact Toroid Injection eXperiment (CTIX) [6] and show that the experimental results support our computed predictions.

Johnson, J N

2009-07-02T23:59:59.000Z

47

PLASMA PROCESSING LABORATORY, DEPT. OF CHEMICAL AND BIOMOLECULAR ENGINEERING DIAGNOSTICS OF HIGHDIAGNOSTICS OF HIGH  

E-Print Network [OSTI]

PLASMA PROCESSING LABORATORY, DEPT. OF CHEMICAL AND BIOMOLECULAR ENGINEERING DIAGNOSTICS for advanced diagnostics techniques Some conventional techniques for measuring basic plasma parameters. Vincent Donnellyand Prof. Vincent Donnelly #12;PLASMA PROCESSING LABORATORY, DEPT. OF CHEMICAL

Economou, Demetre J.

48

Tunable Laser Plasma Accelerator based on Longitudinal Density Tailoring  

SciTech Connect (OSTI)

Laser plasma accelerators have produced high-quality electron beams with GeV energies from cm-scale devices and are being investigated as hyperspectral fs light sources producing THz to {gamma}-ray radiation and as drivers for future high-energy colliders. These applications require a high degree of stability, beam quality and tunability. Here we report on a technique to inject electrons into the accelerating field of a laser-driven plasma wave and coupling of this injector to a lower-density, separately tunable plasma for further acceleration. The technique relies on a single laser pulse powering a plasma structure with a tailored longitudinal density profile, to produce beams that can be tuned in the range of 100-400 MeV with percent-level stability, using laser pulses of less than 40 TW. The resulting device is a simple stand-alone accelerator or the front end for a multistage higher-energy accelerator.

Gonsalves, Anthony; Nakamura, Kei; Lin, Chen; Panasenko, Dmitriy; Shiraishi, Satomi; Sokollik, Thomas; Benedetti, Carlo; Schroeder, Carl; Geddes, Cameron; Tilborg, Jeroen van; Osterhoff, Jens; Esarey, Eric; Toth, Csaba; Leemans, Wim

2011-07-15T23:59:59.000Z

49

Stable laser–plasma accelerators at low densities  

SciTech Connect (OSTI)

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.

Li, Song; Hafz, Nasr A. M., E-mail: nasr@sjtu.edu.cn; Mirzaie, Mohammad; Ge, Xulei; Sokollik, Thomas; Chen, Min; Sheng, Zhengming; Zhang, Jie, E-mail: jzhang1@sjtu.edu.cn [Key Laboratory for Laser Plasmas (Ministry of Education) and Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China)

2014-07-28T23:59:59.000Z

50

Princeton Plasma Physics Laboratory NSTX Experimental Proposal  

E-Print Network [OSTI]

Operations Chit Review Board (designated by Run Coordinator) MINOR MODIFICATIONS (Approved by Experimental and detailed nature of the inertial effects and dissipation mechanisms have yet to be determined. The strength, and neoclassical effects. Active braking of the plasma rotation by externally applied fields will be used to alter

Princeton Plasma Physics Laboratory

51

Princeton Plasma Physics Laboratory NSTX Experimental Proposal  

E-Print Network [OSTI]

Review Board (designated by Run Coordinator) MINOR MODIFICATIONS (Approved by Experimental Research in NSTX and DIII-D. Because the physics of ELM mitigation by non- axisymmetric fields is not established, this experiment is somewhat exploratory in nature. For instance, plasma targets with various edge q

Princeton Plasma Physics Laboratory

52

Erik P. Gilson Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

. #12;·Beam mismatch and envelope instabilities ·Collective wave excitations ·Chaotic particle dynamics ­ Consistent with Thermal Equilibrium · n(0) = 1.4×105 cm-3 · R = 1.4 cm · s = 0.2 WARP 3D Distances of 7.5 km #12;Temporarily Changing the Amplitude Causes the Plasma Envelope to Oscillate 5 Cycles

Gilson, Erik

53

Princeton Plasma Physics Laboratory NSTX Experimental Proposal  

E-Print Network [OSTI]

-mode plasmas, using Neon injection and the (diode based) USXR poloidal arrays. While thermal ion transport in H H- modes by using deuterated-methane and neon gas puffs as well as vitreous carbon pellet injection. We will first attempt injection into ELM-free H-modes by applying brief (50-200 ms) gas puffs

Princeton Plasma Physics Laboratory

54

Laboratory Dipole Plasma Physics Columbia University  

E-Print Network [OSTI]

years of magnetospheric research: earth, Jupiter... · Dipole is simplest confinement field · Naturally occurring high- plasma ( ~ 2 in Jupiter) · p and ne strongly peaked · Relevant to space science & fusion strong inward particle pinch (radiation belts) #12;Magnetic topology determines equilibrium and stability

55

Observation of low magnetic field density peaks in helicon plasma  

SciTech Connect (OSTI)

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.

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

2013-04-15T23:59:59.000Z

56

Laboratory testing of high energy density capacitors for electric vehicles  

SciTech Connect (OSTI)

Laboratory tests of advanced, high energy density capacitors in the Battery Test Laboratory of the Idaho National Engineering Laboratory have been performed to investigate their suitability for load-leveling the battery in an electric vehicle. Two types of devices were tested -- 3 V, 70 Farad, spiral wound, carbon-based, single cell devices and 20 V, 3. 5 Farad, mixed-oxide, multi-cell bipolar devices. The energy density of the devices, based on energy stored during charge to the rated voltage, was found to be 1--2 Wh/kg, which agreed well with that claimed by the manufacturers. Constant power discharge tests were performed at power densities up to 1500 W/kg. Discharges at higher power densities could have been performed had equipment been available to maintain constant power during discharges of less than one second. It was found that the capacitance of the devices were rate dependent with the rate dependency of the carbon-based devices being higher than that of the mixed-oxide devices. The resistance of both types of devices were relatively low being 20--30 milliohms. Testing done in the study showed that the advanced high energy density capacitors can be charged and discharged over cycles (PSFUDS) which approximate the duty cycle that would be encountered if the devices are used to load-level the battery in an electric vehicle. Thermal tests of the advanced capacitors in an insulated environment using the PSFUDS cycle showed the devices do not overheat with their temperatures increasing only 4--5{degrees}C for tests that lasted 5--7 hours. 7 refs., 33 figs., 11 tabs.

Burke, A.F.

1991-10-01T23:59:59.000Z

57

Final Progress Report for Ionospheric Dusty Plasma In the Laboratory [Smokey Plasma  

SciTech Connect (OSTI)

“Ionospheric Dusty Plasma in the Laboratory” is a research project with the purpose of finding and reproducing the characteristics of plasma in the polar mesosphere that is unusually cold (down to 140 K) and contains nanometer-sized dust particles. This final progress report summarizes results from four years of effort that include a final year with a no-cost extension.

Robertson, Scott [Professor

2010-09-28T23:59:59.000Z

58

Debye size microprobes for electric field measurements in laboratory plasmas  

SciTech Connect (OSTI)

Microelectromechanical systems (MEMS) have led to the development of a host of tiny machines and sensors over the past decade. Plasma physics is in great need of small detectors for several reasons. First of all, very small detectors do not disturb a plasma, and secondly some detectors can only work because they are very small. We report on the first of a series of small (sub-Debye length) probes for laboratory plasmas undertaken at the basic Plasma Science Facility at UCLA. The goal of the work is to develop robust and sensitive diagnostic probes that can survive in a plasma. The probes must have electronics packages in close proximity. We report on the construction and testing of probes that measure the electric field.

Pribyl, P.; Gekelman, W.; Nakamoto, M.; Lawrence, E.; Chiang, F.; Stillman, J.; Judy, J.; Katz, N.; Kintner, P.; Niknejadi, P. [Department of Physics Astronomy, University of California, Los Angeles, California 90095 (United States); Department of Electrical Engineering, University of California, Los Angeles, California 90095 (United States); Department of Physics, MIT, Cambridge, Massachussetts (United States); Department of Electrical Engineering, Cornell University, Ithaca, New York 14850 (United States); Cal Poly, Pomona, California 91768 (United States)

2006-07-15T23:59:59.000Z

59

Two-dimensional-spatial distribution measurement of electron temperature and plasma density in low temperature plasmas  

SciTech Connect (OSTI)

A real-time measurement method for two-dimensional (2D) spatial distribution of the electron temperature and plasma density was developed. The method is based on the floating harmonic method and the real time measurement is achieved with little plasma perturbation. 2D arrays of the sensors on a 300 mm diameter wafer-shaped printed circuit board with a high speed multiplexer circuit were used. Experiments were performed in an inductive discharge under various external conditions, such as powers, gas pressures, and different gas mixing ratios. The results are consistent with theoretical prediction. Our method can measure the 2D spatial distribution of plasma parameters on a wafer-level in real-time. This method can be applied to plasma diagnostics to improve the plasma uniformity of plasma reactors for plasma processing.

Kim, Young-Cheol [Department of Nanoscale Semiconductor Engineering, Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791 (Korea, Republic of); Jang, Sung-Ho; Oh, Se-Jin; Lee, Hyo-Chang; Chung, Chin-Wook [Department of Electrical Engineering, Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791 (Korea, Republic of)

2013-05-15T23:59:59.000Z

60

Princeton Plasma Physics Laboratory NSTX Experimental Proposal  

E-Print Network [OSTI]

-mode reflectometry. The electron density scale length (Ln) at the B-X mode conversion layer is an important parameter at the B-X conversion layer. The antenna includes a port for a gas injection valve. #12;NSTX Experimental the Conversion of EBWs to X-Mode on NSTX OP-XP-404 Revision: 0 Effective Date: December 10, 2003 (Ref. OP-AD-97

Princeton Plasma Physics Laboratory

Note: This page contains sample records for the topic "density laboratory plasmas" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Princeton Plasma Physics Laboratory NSTX Experimental Proposal  

E-Print Network [OSTI]

-mode reflectometry. The electron density scale length (Ln) at the B-X mode conversion layer is an important parameter at the B-X conversion layer. The antenna includes a port for a gas injection valve. #12;NSTX Experimental the Conversion of EBWs to X-Mode on NSTX OP-XP- 308 Revision: 3 Effective Date: February 10, 2003 (Ref. OP-AD-97

Princeton Plasma Physics Laboratory

62

US Burning Plasma Workshop Oak Ridge National Laboratory US Contributions to ITER Project (US ITER)  

E-Print Network [OSTI]

US Burning Plasma Workshop Oak Ridge National Laboratory US Contributions to ITER Project (US ITER Plasma Workshop Oak Ridge, TN December 7, 2005 #12;US Burning Plasma Workshop Oak Ridge National '06 Expectations · Summary #12;US Burning Plasma Workshop Oak Ridge National Laboratory Highlights

63

Plasma density gradient injection of low absolute momentum spread electron bunches  

E-Print Network [OSTI]

t to the plasma density indicates the laser focus positionplasma exit. Scanning the jet position relative to the laser focus (

Geddes, C.G.R.

2008-01-01T23:59:59.000Z

64

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

SciTech Connect (OSTI)

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.

Perego, M.; Gunzburger, M. D. [Department of Scientific Computing, Florida State University, Tallahassee, Florida 32306 (United States)] [Department of Scientific Computing, Florida State University, Tallahassee, Florida 32306 (United States); Howell, P. D.; Ockendon, J. R.; Allen, J. E. [OCIAM, Mathematical Institute, Oxford University, 24-29 St Giles, OX1 3LB Oxford (United Kingdom)] [OCIAM, Mathematical Institute, Oxford University, 24-29 St Giles, OX1 3LB Oxford (United Kingdom)

2013-05-15T23:59:59.000Z

65

P24 Plasma Physics Summer School 2012 Los Alamos National Laboratory Summer lecture series for students  

SciTech Connect (OSTI)

This report covers the 2012 LANL summer lecture series for students. The lectures were: (1) Tom Intrator, P24 LANL: Kick off, Introduction - What is a plasma; (2) Bruno Bauer, Univ. Nevada-Reno: Derivation of plasma fluid equations; (3) Juan Fernandez, P24 LANL Overview of research being done in p-24; (4) Tom Intrator, P24 LANL: Intro to dynamo, reconnection, shocks; (5) Bill Daughton X-CP6 LANL: Intro to computational particle in cell methods; (6) Kirk Flippo, P24 LANL: High energy density plasmas; (7) Thom Weber, P24 LANL: Energy crisis, fission, fusion, non carbon fuel cycles; (8) Tom Awe, Sandia National Laboratory: Magneto Inertial Fusion; and (9) Yongho Kim, P24 LANL: Industrial technologies.

Intrator, Thomas P. [Los Alamos National Laboratory; Bauer, Bruno [Univ Nevada, Reno; Fernandez, Juan C. [Los Alamos National Laboratory; Daughton, William S. [Los Alamos National Laboratory; Flippo, Kirk A. [Los Alamos National Laboratory; Weber, Thomas [Los Alamos National Laboratory; Awe, Thomas J. [Los Alamos National Laboratory; Kim, Yong Ho [Los Alamos National Laboratory

2012-09-07T23:59:59.000Z

66

Princeton Plasma Physics Laboratory FY2003 Annual Highlights  

SciTech Connect (OSTI)

The Princeton Plasma Physics Laboratory FY2003 Annual Highlights report provides a summary of the activities at the Laboratory for the fiscal year--1 October 2002 through 30 September 2003. The report includes the Laboratory's Mission and Vision Statements, a message ''From the Director,'' summaries of the research and engineering activities by project, and sections on Technology Transfer, the Graduate and Science Education Programs, Awards and Honors garnered by the Laboratory and the employees, and the Year in Pictures. There is also a listing of the Laboratory's publications for the year and a section of the abbreviations, acronyms, and symbols used throughout the report. In the PDF document, links have been created from the Table of Contents to each section. You can also return to the Table of Contents from the beginning page of each section. The PPPL Highlights for fiscal year 2003 is also available in hardcopy format. To obtain a copy e-mail Publications and Reports at: pub-reports@pppl.gov. Be sure to include your complete mailing address

Editors: Carol A. Phillips; Anthony R. DeMeo

2004-08-23T23:59:59.000Z

67

Dusty plasma diagnostics methods for charge, electron temperature, and ion density  

E-Print Network [OSTI]

Dusty plasma diagnostics methods for charge, electron temperature, and ion density Bin Liu,1 J 2010; published online 7 May 2010 Diagnostic methods are developed to measure the microparticle charge Q and two plasma parameters, electron temperature Te, and ion density ni, in the main plasma region

Goree, John

68

Approach for control of high-density plasma reactors through optimal pulse shaping*  

E-Print Network [OSTI]

Approach for control of high-density plasma reactors through optimal pulse shaping* Tyrone L and it relies on a physical model of the plasma reactor used in conjunction with an optimal control algorithm high-density plasma reactor. Optimal power input pulse shapes and pulsing frequencies are determined

Raja, Laxminarayan L.

69

Counter-facing plasma focus system as a repetitive and/or long-pulse high energy density plasma source  

SciTech Connect (OSTI)

A plasma focus system composed of a pair of counter-facing coaxial plasma guns is proposed as a long-pulse and/or repetitive high energy density plasma source. A proof-of-concept experiment demonstrated that with an assist of breakdown and outer electrode connections, current sheets evolved into a configuration for stable plasma confinement at the center of the electrodes. The current sheets could successively compress and confine the high energy density plasma every half period of the discharge current, enabling highly repetitive light emissions in extreme ultraviolet region with time durations in at least ten microseconds.

Aoyama, Yutaka; Nakajima, Mitsuo; Horioka, Kazuhiko [Department of Energy Sciences, Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8502 (Japan)

2009-11-15T23:59:59.000Z

70

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, for the first time, positron beams. We also discuss measure­ ments on plasma lens­induced synchrotron radiation and laser­ and beam­plasma interactions. 1 INTRODUCTION The plasma lens was proposed as a final focusing

71

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

SciTech Connect (OSTI)

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.

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

2014-03-30T23:59:59.000Z

72

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

SciTech Connect (OSTI)

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.

Nishikawa, Takeshi, E-mail: nishikawa.takeshi@okayama-u.ac.jp [Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530 (Japan)

2014-07-15T23:59:59.000Z

73

Basic Research Needs for High Energy Density Laboratory Physics  

National Nuclear Security Administration (NNSA)

limits? Why is it important? Many plasma structures in the universe, such as gamma-ray bursts, accretion disks around massive black holes and the magnetospheres of radio...

74

Analysis of line integrated electron density using plasma position data on Korea Superconducting Tokamak Advanced Research  

SciTech Connect (OSTI)

A 280 GHz single-channel horizontal millimeter-wave interferometer system has been installed for plasma electron density measurements on the Korea Superconducting Tokamak Advanced Research (KSTAR) device. This system has a triangular beam path that does not pass through the plasma axis due to geometrical constraints in the superconducting tokamak. The term line density on KSTAR has a different meaning from the line density of other tokamaks. To estimate the peak density and the mean density from the measured line density, information on the position of the plasma is needed. The information has been calculated from tangentially viewed visible images using the toroidal symmetry of the plasma. Interface definition language routines have been developed for this purpose. The calculated plasma position data correspond well to calculation results from magnetic analysis. With the position data and an estimated plasma profile, the peak density and the mean density have been obtained from the line density. From these results, changes of plasma density themselves can be separated from effects of the plasma movements, so they can give valuable information on the plasma status.

Nam, Y. U.; Chung, J. [National Fusion Research Institute, Gwahangno 113, Daejeon 305-333 (Korea, Republic of)

2010-10-15T23:59:59.000Z

75

CENTER FOR PULSED POWER DRIVEN HIGH ENERGY DENSITY PLASMA STUDIES  

SciTech Connect (OSTI)

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.

Professor Bruce R. Kusse; Professor David A. Hammer

2007-04-18T23:59:59.000Z

76

Effect of density changes on tokamak plasma confinement  

E-Print Network [OSTI]

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...

Spineanu, F

2015-01-01T23:59:59.000Z

77

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-SeriesFlickr FlickrGuidedCH2M HILL

78

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-SeriesFlickr FlickrGuidedCH2M HILLAdministration | National Nuclear Security

79

Efficient plasma production by intense laser irradiation of low density foam targets  

SciTech Connect (OSTI)

Experimental investigations conducted on low density structured materials, such as foams have been presented in this paper. These low density foam targets having a density greater than the critical density of the laser produced plasma ({rho}{sub cr{approx_equal}}3 mg{center_dot}cm{sup -3} at laser wavelength 1.06 {mu}m) have been envisaged to have enhanced laser absorption. Experiments were done with an indigenously developed, focused 15 Joule/500 ps Nd: Glass laser at {lambda} = 1064 nm. The focused laser intensity on the target was in the range of I{approx_equal}10{sup 13}-2x10{sup 14} W/cm{sup 2}. Laser absorption was determined by energy balance experiments. Laser energy absorption was observed to be higher than 85%. In another set of experiments, low density carbon foam targets of density 150 mg/cc were compared with the solid carbon targets. The x-ray emission in the soft x-ray region was observed to increase in foam target by about 1.8 times and 2.3 times in carbon foam and Pt doped foam as compared to solid carbon. Further, investigations were also carried out to measure the energy transmitted through the sub-critical density TAC foam targets having a density less than 3 mg/cc. Such targets have been proposed to be used for smoothening of intensity ripples in a high power laser beam profile. Transmission exceeding 1.87% has been observed and consistent with results from other laboratories.

Tripathi, S.; Chaurasia, S.; Munda, D. S.; Gupta, N. K.; Dhareshwar, L. J. [Laser and Neutron Physics Division, Bhabha Atomic Research Centre, Mumbai 85 (India); Nataliya, B. [Lebedev Physical Institute, Moscow (Russian Federation)

2010-12-01T23:59:59.000Z

80

High energy density micro plasma bunch from multiple laser interaction with thin target  

SciTech Connect (OSTI)

Three-dimensional particle-in-cell simulation is used to investigate radiation-pressure driven acceleration and compression of small solid-density plasma by intense laser pulses. It is found that multiple impacts by presently available short-pulse lasers on a small hemispheric shell target can create a long-living tiny quasineutral monoenergetic plasma bunch of very high energy density.

Xu, Han [National Laboratory for Parallel and Distributed Processing, College of Computer Science, National University of Defense Technology, Changsha 410073 (China); Shanghai Institute of Optics and Fine Mechanics, Shanghai 201800 (China); Yu, Wei; Luan, S. X.; Xu, Z. Z. [Shanghai Institute of Optics and Fine Mechanics, Shanghai 201800 (China); Yu, M. Y., E-mail: myyu@zju.edu.cn [Physics Department, Institute for Fusion Theory and Simulation, Zhejiang University, Hangzhou 310027 (China); Institute for Theoretical Physics I, Ruhr University, Bochum D-44780 (Germany); Cai, H. B.; Zhou, C. T. [Institute of Applied Physics and Computational Mathematics, Beijing 100088 (China); Yang, X. H.; Yin, Y.; Zhuo, H. B. [College of Science, National University of Defense Technology, Changsha (China); Wang, J. W. [Shanghai Institute of Optics and Fine Mechanics, Shanghai 201800 (China); Institute of Laser Engineering, Osaka University, Osaka 565-0871 (Japan); Murakami, M. [Institute of Laser Engineering, Osaka University, Osaka 565-0871 (Japan)

2014-01-13T23:59:59.000Z

Note: This page contains sample records for the topic "density laboratory plasmas" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

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

E-Print Network [OSTI]

-produced plasma (LPP) for various applications should consider details of spatial and temporal input power de 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

Harilal, S. S.

82

High Density Sensor Network Development | The Ames Laboratory  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation ProposedUsingFun withconfinement plasmas in the Madison SymmetricHigh Carbon Fly Ashand

83

Spatially extended void-free dusty plasmas in a laboratory radio-frequency discharge  

SciTech Connect (OSTI)

Laboratory experiments with thermophoretic levitation of dust are described that aim at the closure of a central dust-free void region. A careful study of the void structure as a function of the discharge and levitation parameters leads to the discovery of an extended parameter region where stable void-free equilibria are found. The void closure is effected by a novel mechanism that involves a self-organized change in the discharge topology, in which the dust cloud becomes surrounded by a toroidal region of plasma production. In this geometry ions are found to stream radially inwards instead of outwards as in clouds with a central void. This change in ion flow is proved by a reversal of the propagation direction of dust-density waves.

Schmidt, C.; Arp, O.; Piel, A. [IEAP, Christian-Albrechts-Universitaet Kiel, D-24098 Kiel (Germany)

2011-01-15T23:59:59.000Z

84

Experimental observation of 3-D, impulsive reconnection events in a laboratory plasma  

SciTech Connect (OSTI)

Fast, impulsive reconnection is commonly observed in laboratory, space, and astrophysical plasmas. In this work, impulsive, local, 3-D reconnection is identified for the first time in a laboratory current sheet. The two-fluid, impulsive reconnection events observed on the Magnetic Reconnection Experiment (MRX) [Yamada et al., Phys Plasmas 4, 1936 (1997)] cannot be explained by 2-D models and are therefore fundamentally three-dimensional. Several signatures of flux ropes are identified with these events; 3-D high current density regions with O-point structure form during a slow buildup period that precedes a fast disruption of the reconnecting current layer. The observed drop in the reconnection current and spike in the reconnection rate during the disruption are due to ejection of these flux ropes from the layer. Underscoring the 3-D nature of the events, strong out-of-plane gradients in both the density and reconnecting magnetic field are found to play a key role in this process. Electromagnetic fluctuations in the lower hybrid frequency range are observed to peak at the disruption time; however, they are not the key physics responsible for the impulsive phenomena observed. Important features of the disruption dynamics cannot be explained by an anomalous resistivity model. An important discrepancy in the layer width and force balance between the collisionless regime of MRX and kinetic simulations is also revisited. The wider layers observed in MRX may be due to the formation of flux ropes with a wide range of sizes; consistent with this hypothesis, flux rope signatures are observed down to the smallest scales resolved by the diagnostics. Finally, a 3-D two-fluid model is proposed to explain how the observed out-of-plane variation may lead to a localized region of enhanced reconnection that spreads in the direction of the out-of-plane electron flow, ejecting flux ropes from the layer in a 3-D manner.

Dorfman, S.; Ji, H.; Yamada, M.; Yoo, J.; Lawrence, E.; Myers, C.; Tharp, T. D. [Center for Magnetic Self-Organization, Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)] [Center for Magnetic Self-Organization, Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)

2014-01-15T23:59:59.000Z

85

Radiation transport and density effects in non-equilibrium plasmas Vladimir I. Fisher*, Dimitri V. Fisher, Yitzhak Maron  

E-Print Network [OSTI]

Radiation transport and density effects in non-equilibrium plasmas Vladimir I. Fisher*, Dimitri V populations and the radiation field in transient non-equilibrium plasmas. In this model, the plasma density to a self-consistent treatment of the radiative transfer. For non-Maxwellian plasmas, the atomic

86

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)

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.

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)

2014-03-15T23:59:59.000Z

87

Using Radio Waves to Control Fusion Plasma Density  

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

heat goes to electrons instead of plasma ions, as would happen in the center of a self-sustaining fusion reaction. Supercomputer simulations run at the Department of Energy's...

88

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

SciTech Connect (OSTI)

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.

Habibi, M. [Department of Physics, Shirvan Branch, Islamic Azad University, Shirvan (Iran, Islamic Republic of); Ghamari, F. [Department of Physics, Khorramabad Branch, Islamic Azad University, Khorramabad (Iran, Islamic Republic of)

2012-10-15T23:59:59.000Z

89

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

E-Print Network [OSTI]

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 ...

Boxer, Alexander C

2009-01-01T23:59:59.000Z

90

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

SciTech Connect (OSTI)

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

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

2012-10-15T23:59:59.000Z

91

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

E-Print Network [OSTI]

Plasma density inside a femtosecond laser filament in air: Strong dependence on external focusing­16 . The plasma generation balances the self-focusing effect and leads to a limited peak intensity 17­19 along, Germany Received 10 March 2006; published 27 September 2006 Our experiment shows that external focusing

Becker, Andreas

92

Magnetic reconnection with Sweet-Parker characteristics in two-dimensional laboratory plasmas*  

E-Print Network [OSTI]

changes in macroscopic configurations, such as in solar flares,4 magnetospheric substorms,4 and re mechanism for re- leasing the energy stored in the magnetic field to plasma kinetic and thermal energies as observed in solar flares, au- roral phenomena, and laboratory plasmas. Magnetic reconnection was first

Ji, Hantao

93

electric Probe Applications Laboratory, Hanyang University DiPS (Diversified Plasma Simulator)  

E-Print Network [OSTI]

electric Probe Applications Laboratory, Hanyang University DiPS (Diversified Plasma Simulator Science, Toki, Gifu, Japan Kyu-Sun Chung and ePALers* Hanyang University, Seoul, Korea #12;electric Probe and processing plasmas with various electric probes: fast-scanning single probe, triple probe, Mach probe, slow

Princeton Plasma Physics Laboratory

94

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

SciTech Connect (OSTI)

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.

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)

2012-08-15T23:59:59.000Z

95

Path Integral Monte Carlo Simulation of the Low-Density Hydrogen Plasma B. Militzer y  

E-Print Network [OSTI]

Path Integral Monte Carlo Simulation of the Low-Density Hydrogen Plasma B. Militzer y Lawrence to calculate the equilibrium properties of hydrogen in the density and temperature range of 9:83 #2; 10 4 #20 surface. We calculate the equation of state and compare with other models for hydrogen valid

Militzer, Burkhard

96

Transient evolution of solitary electron holes in low pressure laboratory plasma  

E-Print Network [OSTI]

Solitary electrons holes (SEHs) are localized electrostatic positive potential structures in collisionless plasmas. These are vortex-like structures in the electron phase space. Its existence is cause of distortion of the electron distribution in the resonant region. These are explained theoretically first time by Schamel et.al [Phys. Scr. 20, 336 (1979) and Phys. Plasmas 19, 020501 (2012)]. Propagating solitary electron holes can also be formed in a laboratory plasma when a fast rising high positive voltage pulse is applied to a metallic electrode [Kar et. al., Phys. Plasmas 17, 102113 (2010)] immersed in a low pressure plasma. The temporal evolution of these structures can be studied by measuring the transient electron distribution function (EDF). In the present work, transient EDF is measured after formation of a solitary electron hole in nearly uniform, unmagnetized, and collisionless plasma for applied pulse width and, where and are applied pulse width and inverse of ion plasma frequency respectively. Fo...

Choudhary, Mangilal; Mukherjee, Subroto

2015-01-01T23:59:59.000Z

97

Plasma-materials interaction results at Sandia National Laboratories.  

SciTech Connect (OSTI)

Overview of Plasma Materials Interaction (PMI) activities are: (1) Hydrogen diffusion and trapping in metals - (a) Growth of hydrogen precipitates in tungsten PFCs, (b) Temperature dependence of deuterium retention at displacement damage, (c) D retention in W at elevated temperatures; (2) Permeation - (a) Gas driven permeation results for W/Mo/SiC, (b) Plasma-driven permeation test stand for TPE; and (3) Surface studies - (a) H-sensor development, (b) Adsorption of oxygen and hydrogen on beryllium surfaces.

Causey, Rion A.; Wampler, William R. (Sandia National Laboratories, Albuquerque, NM); Buchenauer, Dean A.; Karnesky, Richard A.; Whaley, Josh A.; Cowgill, Donald F.; Kolasinski, Robert D.

2010-08-01T23:59:59.000Z

98

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

DOE Patents [OSTI]

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.

Thode, Lester E. (Los Alamos, NM)

1981-01-01T23:59:59.000Z

99

Extreme ultraviolet source at 6.7 nm based on a low-density plasma  

SciTech Connect (OSTI)

We demonstrate an efficient extreme ultraviolet (EUV) source for operation at {lambda} = 6.7 nm by optimizing the optical thickness of gadolinium (Gd) plasmas. Using low initial density Gd targets and dual laser pulse irradiation, we observed a maximum EUV conversion efficiency (CE) of 0.54% for 0.6% bandwidth (BW) (1.8% for 2% BW), which is 1.6 times larger than the 0.33% (0.6% BW) CE produced from a solid density target. Enhancement of the EUV CE by use of a low-density plasma is attributed to the reduction of self-absorption effects.

Higashiguchi, Takeshi; Yugami, Noboru [Department of Advanced Interdisciplinary Sciences, Center for Optical Research and Education (CORE), and Optical Technology Innovation Center (OpTIC), Utsunomiya University, Yoto 7-1-2, Utsunomiya, Tochigi 321-8585 (Japan); Japan Science and Technology Agency, CREST, 4-1-8 Honcho, Kanagawa, Saitama 332-0012 (Japan); Otsuka, Takamitsu [Department of Advanced Interdisciplinary Sciences, Center for Optical Research and Education (CORE), and Optical Technology Innovation Center (OpTIC), Utsunomiya University, Yoto 7-1-2, Utsunomiya, Tochigi 321-8585 (Japan); Jiang, Weihua [Department of Electrical Engineering, Nagaoka University of Technology, Kami-tomiokamachi 1603-1, Nagaoka, Niigata 940-2188 (Japan); Endo, Akira [Research Institute for Science and Engineering, Waseda University, Okubo 3-4-1, Shinjuku, Tokyo 169-8555 (Japan); Li Bowen; Kilbane, Deirdre; Dunne, Padraig; O'Sullivan, Gerry [School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland)

2011-11-07T23:59:59.000Z

100

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

SciTech Connect (OSTI)

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.

Bulanov, Sergei V.; Esirkepov, Timur Zh.; Kando, Masaki; Koga, James K.; Pirozhkov, Alexander S.; Nakamura, Tatsufumi [QuBS, Japan Atomic Energy Agency, 1-8-7 Umemidai, Kizugawa, Kyoto 619-0215 (Japan); Bulanov, Stepan S. [University of California, Berkeley, California 94720 (United States); Schroeder, Carl B.; Esarey, Eric [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Califano, Francesco; Pegoraro, Francesco [Physics Department, University of Pisa, Pisa 56127 (Italy)

2012-11-15T23:59:59.000Z

Note: This page contains sample records for the topic "density laboratory plasmas" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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101

Princeton Plasma Physics Laboratory. Annual report, October 1, 1989--September 30, 1990  

SciTech Connect (OSTI)

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.

Not Available

1990-12-31T23:59:59.000Z

102

Princeton University, Plasma Physics Laboratory annual report, October 1, 1988--September 30, 1989  

SciTech Connect (OSTI)

This report contains discussions on the following topics: principal parameters achieved in experimental devices (FY89); tokamak fusion test reactor; compact ignition tokamak; princeton beta experiment- modification; current drive experiment; international collaboration; x-ray laser studies; spacecraft glow experiment; plasma 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 (FY89); graduate education: plasma physics; graduate education: plasma science and technology; and Princeton Plasmas Physics Laboratory Reports (FY89).

Not Available

1989-12-31T23:59:59.000Z

103

Princeton University, Plasma Physics Laboratory annual report, October 1, 1988--September 30, 1989  

SciTech Connect (OSTI)

This report contains discussions on the following topics: principal parameters achieved in experimental devices (FY89); tokamak fusion test reactor; compact ignition tokamak; princeton beta experiment- modification; current drive experiment; international collaboration; x-ray laser studies; spacecraft glow experiment; plasma 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 (FY89); graduate education: plasma physics; graduate education: plasma science and technology; and Princeton Plasmas Physics Laboratory Reports (FY89).

Not Available

1989-01-01T23:59:59.000Z

104

White Paper: Fusion Simulation Program (FSP) (July 26, 2012) W. M. Tang (Princeton University, Plasma Physics Laboratory)  

E-Print Network [OSTI]

the core plasma to the associated engineering systems. The FSP will initially focus on producing: (i, Plasma Physics Laboratory) In view of the current ITER fiscal issues, it is particularly important, projections for plasma performance in the international burning plasma ITER experiment have been based

105

Plasma behaviour at high beta and high density in the Madison Symmetric Torus RFP  

SciTech Connect (OSTI)

Pellet fuelling of improved confinement Madison Symmetric Torus (MST) plasmas has resulted in high density and high plasma beta. The density in improved confinement discharges has been increased fourfold, and a record plasma beta (beta(tot) = 26%) for the improved confinement reversed-field pinch (RFP) has been achieved. At higher beta, a new regime for instabilities is accessed in which local interchange and global tearing instabilities are calculated to be linearly unstable, but experimentally, no severe effect, e. g., a disruption, is observed. The tearing instability, normally driven by the current gradient, is driven by the pressure gradient in this case, and there are indications of increased energy transport ( as compared with low-density improved confinement). Pellet fuelling is also compared with enhanced edge fuelling of standard confinement RFP discharges for the purpose of searching for a density limit in MST. In standard-confinement discharges, pellet fuelling peaks the density profile where edge fuelling cannot, but transport appears unchanged. For a limited range of plasma current, MST discharges with edge fuelling are constrained to a maximum density corresponding to the Greenwald limit. This limit is surpassed in pellet-fuelled improved confinement discharges.

Wyman, M. [University of Wisconsin, Madison; Chapman, B. E. [University of Wisconsin, Madison; Ahn, J. W. [University of Wisconsin, Madison; Almagri, A. F. [University of Wisconsin, Madison; Anderson, J. [University of Wisconsin, Madison; Bonomo, F. [Consorzio RFX, Italy; Bower, D L [University of California, Los Angeles; Combs, Stephen Kirk [ORNL; Craig, D. [University of Wisconsin, Madison; Foust, Charles R [ORNL

2009-01-01T23:59:59.000Z

106

E-Print Network 3.0 - av accelerates plasma Sample Search Results  

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

for Plasma in the Laboratory and Astrophysics Collection: Physics ; Plasma Physics and Fusion 5 Lower hybrid current drive at densities required for thermonuclear reactors R....

107

Princeton Plasma Physics Laboratory - 1995 Highlights. Fiscal Year 1995, 1 October 1994--30 September 1995  

SciTech Connect (OSTI)

The purpose of this Highlights Report is to present a brief overview of the Laboratory`s significant research accomplishments during the fiscal year 1995. The activities covered in this report include advances on the large projects, such as the discovery of the Enhanced Reversed Shear mode on the TFTR and the engineering design developments in the International Thermonuclear Experimental Reactor project, as well as the significant progress made in plasma theory, small-scale experiments, technology transfer, graduate education, and the Laboratory`s outreach program in science education.

NONE

1996-12-01T23:59:59.000Z

108

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

SciTech Connect (OSTI)

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.

Sati, Priti; Tripathi, V. K. [Indian Institute of Technology, Hauz Khas, Delhi 110054 (India)

2012-12-15T23:59:59.000Z

109

Rapid multiplexed data acquisition: Application to three-dimensional magnetic field measurements in a turbulent laboratory plasma  

E-Print Network [OSTI]

acquisition at the Swarthmore Spheromak Experiment SSX and Redmond Plasma Physics Laboratory. An application. The Swarthmore Spheromak Experiment SSX 3 has re- cently completed construction, calibration, and testing

Brown, Michael R.

110

Photoemission rate of strongly interacting quark-gluon plasma at finite density  

SciTech Connect (OSTI)

We calculate the thermal spectral function of strongly interacting Yang-Mills plasma with finite density using the holographic technique. The gravity dual of the finite temperature and density is taken as the Reissner-Nordstroem-anti-de Sitter black hole. In the presence of charge, linearized vector modes of gravitational and electromagnetic perturbation are coupled with each other. By introducing master variables for these modes, we solve the coupled system and calculate spectral function. The spectral function gets a new peak due to the density effect, which is most dramatic in the momentum plot with fixed frequency. We also calculate the photoemission rate of our gauge theory plasma from the spectral function for lightlike momentum. AC, dc conductivity, and their density dependence is also computed.

Jo, Kwanghyun; Sin, Sang-Jin [Department of Physics, Hanyang University, Seoul 133-791 (Korea, Republic of)

2011-01-15T23:59:59.000Z

111

The formation of reverse shocks in magnetized high energy density supersonic plasma flows  

SciTech Connect (OSTI)

A new experimental platform was developed, based on the use of supersonic plasma flow from the ablation stage of an inverse wire array z-pinch, for studies of shocks in magnetized high energy density physics plasmas in a well-defined and diagnosable 1-D interaction geometry. The mechanism of flow generation ensures that the plasma flow (Re{sub M}???50, M{sub S}???5, M{sub A}???8, V{sub flow}???100?km/s) has a frozen-in magnetic field at a level sufficient to affect shocks formed by its interaction with obstacles. It is found that in addition to the expected accumulation of stagnated plasma in a thin layer at the surface of a planar obstacle, the presence of the magnetic field leads to the formation of an additional detached density jump in the upstream plasma, at a distance of ?c/?{sub pi} from the obstacle. Analysis of the data obtained with Thomson scattering, interferometry, and local magnetic probes suggests that the sub-shock develops due to the pile-up of the magnetic flux advected by the plasma flow.

Lebedev, S. V., E-mail: s.lebedev@imperial.ac.uk, E-mail: l.suttle10@imperial.ac.uk; Suttle, L.; Swadling, G. F.; Bennett, M.; Bland, S. N.; Burdiak, G. C.; Chittenden, J. P.; Grouchy, P. de; Hall, G. N.; Hare, J. D.; Kalmoni, N.; Niasse, N.; Patankar, S.; Smith, R. A.; Suzuki-Vidal, F. [Blackett Laboratory, Imperial College, London SW7 2BW (United Kingdom)] [Blackett Laboratory, Imperial College, London SW7 2BW (United Kingdom); Burgess, D.; Clemens, A. [Astronomy Unit, School of Physics and Astronomy, Queen Mary University of London, London E1 4NS (United Kingdom)] [Astronomy Unit, School of Physics and Astronomy, Queen Mary University of London, London E1 4NS (United Kingdom); Ciardi, A. [LERMA, Observatoire de Paris and École Normale Supérieure Université Pierre et Marie Curie, UMR 8112 CNRS, 75231 Paris (France)] [LERMA, Observatoire de Paris and École Normale Supérieure Université Pierre et Marie Curie, UMR 8112 CNRS, 75231 Paris (France); Sheng, L. [Blackett Laboratory, Imperial College, London SW7 2BW (United Kingdom) [Blackett Laboratory, Imperial College, London SW7 2BW (United Kingdom); Northwest Institute of Nuclear Technology, Xi'an 710024 (China); Yuan, J. [Blackett Laboratory, Imperial College, London SW7 2BW (United Kingdom) [Blackett Laboratory, Imperial College, London SW7 2BW (United Kingdom); Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900 (China); and others

2014-05-15T23:59:59.000Z

112

Final Technical Report - Development of a tunable diode laser induced fluorescence diagnostic for the Princeton magnetic nozzle experiment: West Virginia University and Princeton Plasma Physics Laboratory  

SciTech Connect (OSTI)

This project involves the construction of a compact, portable, laser induced fluorescence (LIF) diagnostic for measurements of neutral helium, neutral argon, and argon ion velocity space distributions in a high density, steady state, helicon source. The project is collaborative effort between the Princeton Plasma Physics Laboratory (PPPL) and the West Virginia University (WVU) helicon source group. A key feature of the diagnostic system will be the use of tunable diode lasers instead of the tunable dye lasers typically used in LIF experiments.

Earl Scime

2006-11-07T23:59:59.000Z

113

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

SciTech Connect (OSTI)

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.

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)

2012-07-15T23:59:59.000Z

114

Earth Planets Space, 53, 539545, 2001 Study of local reconnection physics in a laboratory plasma  

E-Print Network [OSTI]

Earth Planets Space, 53, 539­545, 2001 Study of local reconnection physics in a laboratory plasma reconnection rates are found to be quantitatively consistent with a generalized Sweet-Parker model which of the increased ion energy must be due to nonclassical processes, consistent with the resistivity enhancement

Ji, Hantao

115

Permutation Entropy and Statistical Complexity Analysis of Turbulence in Laboratory Plasmas and the Solar Wind  

E-Print Network [OSTI]

The Bandt-Pompe permutation entropy and the Jensen-Shannon statistical complexity are used to analyze fluctuating time series of three different plasmas: the magnetohydrodynamic (MHD) turbulence in the plasma wind tunnel of the Swarthmore Spheromak Experiment (SSX), drift-wave turbulence of ion saturation current fluctuations in the edge of the Large Plasma Device (LAPD) and fully-developed turbulent magnetic fluctuations of the solar wind taken from the WIND spacecraft. The entropy and complexity values are presented as coordinates on the CH plane for comparison among the different plasma environments and other fluctuation models. The solar wind is found to have the highest permutation entropy and lowest statistical complexity of the three data sets analyzed. Both laboratory data sets have larger values of statistical complexity, suggesting these systems have fewer degrees of freedom in their fluctuations, with SSX magnetic fluctuations having slightly less complexity than the LAPD edge fluctuations. The CH ...

Weck, Peter J; Brown, Michael R; Wicks, Robert T

2014-01-01T23:59:59.000Z

116

COLD BUBBLE FORMATION DURING TOKAMAK DENSITY LIMIT DISRUPTIONS  

E-Print Network [OSTI]

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

Howard, John

117

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

SciTech Connect (OSTI)

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.

Jung Yu, Dae [School of Space Research, Kyung Hee University, Yongin 446-701 (Korea, Republic of)] [School of Space Research, Kyung Hee University, Yongin 446-701 (Korea, Republic of); Kim, Kihong [Department of Energy Systems Research, Ajou University, Suwon 443-749 (Korea, Republic of)] [Department of Energy Systems Research, Ajou University, Suwon 443-749 (Korea, Republic of)

2013-12-15T23:59:59.000Z

118

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

SciTech Connect (OSTI)

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.

Marquez, Ariel [CNEA and Instituto Balseiro, 8402 Bariloche (Argentina); Gonzalez, Jose [INVAP-CONICET and Instituto Balseiro, 8402 Bariloche, Argentina. (Argentina); Tarifeno-Saldivia, Ariel; Pavez, Cristian; Soto, Leopoldo [CCHEN, Comision Chilena de Energia Nuclear, Casilla 188-D, Santiago (Chile); Center for Research and Applications in Plasma Physics and Pulsed Power, P4 (Chile); Clausse, Alejandro [CNEA-CONICET and Universidad Nacional del Centro, 7000 Tandil (Argentina)

2012-01-15T23:59:59.000Z

119

A Laboratory Study of Asymmetric Magnetic Reconnection in Strongly-Driven Plasmas  

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

Magnetic reconnection, the annihilation and rearrangement of magnetic fields in a plasma, is a universal phenomenon that frequently occurs when plasmas carrying oppositely-directed field lines collide. In most natural circumstances the collision is asymmetric (the two plasmas having different properties), but laboratory research to date has been limited to symmetric configurations. Additionally, the regime of strongly-driven magnetic reconnection, where the ram pressure of the plasma dominates the magnetic pressure, as in several astrophysical environments, has also received little experimental attention. Thus, we have designed experiments to probe reconnection in asymmetric, strongly-driven, laser-generated plasmas. Here we show that, in this strongly-driven system, the rate of magnetic flux annihilation is dictated by the relative flow velocities of the opposing plasmas and is insensitive to initial asymmetries. Additionally, out-of-plane magnetic fields that arise from asymmetries in the three-dimensional plasma geometry have minimal impact on the reconnection rate, due to the strong flows.

Rosenberg, M. J.; Li, C. K.; Fox, W.; Igumenshchev, I.; Seguin, F. H.; Town, R. P.J.; Frenje, J. A.; Stoeckl, C.; Glebov, V.; Petrasso, R. D.

2015-02-04T23:59:59.000Z

120

The Madison plasma dynamo experiment: a facility for studying laboratory plasma astrophysics  

E-Print Network [OSTI]

The Madison plasma dynamo experiment (MPDX) is a novel, versatile, basic plasma research device designed to investigate flow driven magnetohydrodynamic (MHD) instabilities and other high-$\\beta$ phenomena with astrophysically relevant parameters. A 3 m diameter vacuum vessel is lined with 36 rings of alternately oriented 4000 G samarium cobalt magnets which create an axisymmetric multicusp that contains $\\sim$14 m$^{3}$ of nearly magnetic field free plasma that is well confined and highly ionized $(>50\\%)$. At present, up to 8 lanthanum hexaboride (LaB$_6$) cathodes and 10 molybdenum anodes are inserted into the vessel and biased up to 500 V, drawing 40 A each cathode, ionizing a low pressure Ar or He fill gas and heating it. Up to 100 kW of electron cyclotron heating (ECH) power is planned for additional electron heating. The LaB$_6$ cathodes are positioned in the magnetized edge to drive toroidal rotation through ${\\bf J}\\times{\\bf B}$ torques that propagate into the unmagnetized core plasma. Dynamo studies...

Cooper, C M; Brookhart, M; Clark, M; Collins, C; Ding, W X; Flanagan, K; Khalzov, I; Li, Y; Milhone, J; Nornberg, M; Nonn, P; Weisberg, D; Whyte, D G; Zweibel, E; Forest, C B

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "density laboratory plasmas" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

The Madison plasma dynamo experiment: A facility for studying laboratory plasma astrophysics  

SciTech Connect (OSTI)

The Madison plasma dynamo experiment (MPDX) is a novel, versatile, basic plasma research device designed to investigate flow driven magnetohydrodynamic instabilities and other high-? phenomena with astrophysically relevant parameters. A 3?m diameter vacuum vessel is lined with 36 rings of alternately oriented 4000?G samarium cobalt magnets, which create an axisymmetric multicusp that contains ?14 m{sup 3} of nearly magnetic field free plasma that is well confined and highly ionized (>50%). At present, 8 lanthanum hexaboride (LaB{sub 6}) cathodes and 10 molybdenum anodes are inserted into the vessel and biased up to 500?V, drawing 40?A each cathode, ionizing a low pressure Ar or He fill gas and heating it. Up to 100?kW of electron cyclotron heating power is planned for additional electron heating. The LaB{sub 6} cathodes are positioned in the magnetized edge to drive toroidal rotation through J?×?B torques that propagate into the unmagnetized core plasma. Dynamo studies on MPDX require a high magnetic Reynolds number Rm?>?1000, and an adjustable fluid Reynolds number 10?1). Initial results from MPDX are presented along with a 0-dimensional power and particle balance model to predict the viscosity and resistivity to achieve dynamo action.

Cooper, C. M.; Brookhart, M.; Collins, C.; Khalzov, I.; Milhone, J.; Nornberg, M.; Weisberg, D.; Forest, C. B. [Department of Physics, University of Wisconsin, Madison, Wisconsin 53706 (United States) [Department of Physics, University of Wisconsin, Madison, Wisconsin 53706 (United States); Center for Magnetic Self Organization, University of Wisconsin, Madison, Wisconsin 53706 (United States); Wallace, J.; Clark, M.; Flanagan, K.; Li, Y.; Nonn, P. [Department of Physics, University of Wisconsin, Madison, Wisconsin 53706 (United States)] [Department of Physics, University of Wisconsin, Madison, Wisconsin 53706 (United States); Ding, W. X. [Department of Physics and Astronomy, University of California, Los Angeles, Los Angeles, California 90024 (United States)] [Department of Physics and Astronomy, University of California, Los Angeles, Los Angeles, California 90024 (United States); Whyte, D. G. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)] [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Zweibel, E. [Department of Physics, University of Wisconsin, Madison, Wisconsin 53706 (United States) [Department of Physics, University of Wisconsin, Madison, Wisconsin 53706 (United States); Center for Magnetic Self Organization, University of Wisconsin, Madison, Wisconsin 53706 (United States); Department of Astronomy, University of Wisconsin, Madison, Wisconsin 53706 (United States)

2014-01-15T23:59:59.000Z

122

Current initiation in low-density foam z-pinch plasmas  

SciTech Connect (OSTI)

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.

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

1996-07-01T23:59:59.000Z

123

Density Diagnostics of the Hot Plasma in AE Aquarii with XMM-Newton  

E-Print Network [OSTI]

High resolution spectroscopy of AE Aquarii with the XMM-Newton RGS has enabled us to measure the electron number density of the X-ray-emitting hot plasma to be ~1E11/cm**-3 by means of intensity ratios of the He-like triplet of Nitrogen and Oxygen. Incorporating with the emission measure evaluated by the EPIC cameras, we have also found a linear scale of the plasma to be ~5E10 cm. Both these values, obtained model-independently, are incompatible with a standard post-shock accretion column of a magnetized white dwarf, but are naturally interpreted as the plasma being formed through interaction between an accretion flow and the magnetosphere of the white dwarf. Our results provide another piece of evidence of the magnetic propeller effect being at work in AE Aqr.

Kei Itoh; Manabu Ishida; Hideyo Kunieda

2004-12-21T23:59:59.000Z

124

Laser-driven hole boring and gamma-ray emission in high-density plasmas  

E-Print Network [OSTI]

Ion acceleration in laser-produced dense plasmas is a key topic of many recent investigations thanks to its potential applications. Besides, at forthcoming laser intensities ($I \\gtrsim 10^{23} \\text{W}\\,\\text{cm}^{-2}$) interaction of laser pulses with plasmas can be accompanied by copious gamma-ray emission. Here we demonstrate the mutual influence of gamma-ray emission and ion acceleration during relativistic hole boring in high-density plasmas with ultra-intense laser pulses. If gamma-ray emission is abundant, laser pulse reflection and hole-boring velocity are lower and gamma-ray radiation pattern is narrower than in the case of low emission. Conservation of energy and momentum allows one to elucidate the effects of gamma-ray emission which are more pronounced at higher hole-boring velocities.

Nerush, Evgeny

2014-01-01T23:59:59.000Z

125

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

SciTech Connect (OSTI)

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.

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)

2014-02-24T23:59:59.000Z

126

Prepared for the U.S. Department of Energy under Contract DE-AC02-76CH03073. Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

05/16/05 Plasma Research Laboratory, Australian National University, Australia Professor I.R. Jones, Institute for Plasma Research, India Ms. P.J. Pathak, Librarian, Institute for Plasma Research, India Dr

127

Prepared for the U.S. Department of Energy under Contract DE-AC02-76CH03073. Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

/16/05 Plasma Research Laboratory, Australian National University, Australia Professor I.R. Jones, Flinders for Plasma Research, India Ms. P.J. Pathak, Librarian, Institute for Plasma Research, India Dr. Pandji

128

Quasilinear dynamics of a cloud of hot electrons propagating through a plasma with decreasing density and temperature  

SciTech Connect (OSTI)

The effects of plasma inhomogeneities on the propagation of a cloud of hot electrons through a cold background plasma and generation of Langmuir waves are investigated using numerical simulations of the quasilinear equations. It is found that in a plasma with decreasing density the quasilinear relaxation of the electron distribution in velocity space is accelerated and the levels of the generated Langmuir waves are enhanced. The magnitude of the induced emission rate is increased and its maximum value moves to lower velocities. Due to density gradient the height of plateau shows an increase at small distances and a corresponding decrease at large distances. It is also found that in a plasma with decreasing temperature, the relaxation of the beam is retarded, the spectral density of Langmuir waves is broadened, and the height of the plateau decreases below its value in a uniform plasma. In the presence of both density and temperature gradients, at given position, the height and upper boundary of the plateau and the level of Langmuir waves are all increased at small velocities. The spatial expansion of the beam is increased by the plasma inhomogeneities, but its average velocity of propagation decreases. Initially, at a given position, the velocity at the upper boundary of the plateau is smaller in the presence of the density gradient than in the uniform plasma but the reverse is true at longer times. Due to temperature gradient, at large times and small distances, the upper boundary of the plateau is increased above its value in the uniform plasma. Because of fast relaxation, the value of the lower boundary of the plateau in the plasma with decreasing density is always less than its value in the uniform plasma. It is found that the local velocity of the beam decreases when the density gradient is present. The local velocity spread of the beam remains unchanged during the propagation of the beam in the uniform plasma, but increases in the presence of inhomogeneities.

Foroutan, G. [Department of Physics, Faculty of Science, Sahand University of Technology, Tabriz 51335-1996 (Iran, Islamic Republic of); School of Physics, The University of Sydney, Sydney NSW 2006 (Australia); Khalilpour, H.; Moslehi-Fard, M. [Faculty of Physics, Tabriz University, Tabriz 51664 (Iran, Islamic Republic of); Li, B.; Robinson, P. A. [School of Physics, University of Sydney, Sydney NSW 2006 (Australia)

2008-12-15T23:59:59.000Z

129

Prepared for the U.S. Department of Energy under Contract DE-AC02-76CH03073. Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

Physics Laboratory Controlled Fusion with Hot-ion Mode in a Degenerate Plasma S. Son and N.J. Fisch December 2005 PPPL-4133 PPPL-4133 #12;Princeton Plasma Physics Laboratory Report Disclaimers Full Legal Availability Princeton Plasma Physics Laboratory This report is posted on the U.S. Department of Energy

130

Prepared for the U.S. Department of Energy under Contract DE-AC02-76CH03073. Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

Physics Laboratory Ignition Regime for Fusion in a Degenerate Plasma S. Son and N.J. Fisch December 2005 PPPL-4138 PPPL-4138 #12;Princeton Plasma Physics Laboratory Report Disclaimers Full Legal Disclaimer Physics Laboratory This report is posted on the U.S. Department of Energy's Princeton Plasma Physics

131

Prepared for the U.S. Department of Energy under Contract DE-AC02-09CH11466. Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

Physics Laboratory PPPL- 4535PPPL-4535 A Midsize Tokamak As Fast Track To Burning Plasmas July, 2010 Ernesto Mazzucato #12;Princeton Plasma Physics Laboratory Report Disclaimers Full Legal Disclaimer Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA ABSTRACT This paper describes

Mazzucato, Ernesto

132

Prepared for the U.S. Department of Energy under Contract DE-AC02-76CH03073. Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

Physics Laboratory Solenoid-free Plasma Startup in NSTX using Coaxial Helicity Injection Roger Raman, Masayoshi Nagata, and Ted Biewer January 2005 PRINCETON PLASMA PHYSICS LABORATORY PPPL PPPL-4042 PPPL-4042 on the U.S. Department of Energy's Princeton Plasma Physics Laboratory Publications and Reports web site

133

Nonlinear plasma waves excitation by intense ion beams in background plasma  

E-Print Network [OSTI]

describe the plasma perturbations well.5 Here, we focus on the general case where the plasma density hasNonlinear plasma waves excitation by intense ion beams in background plasma Igor D. Kaganovich, Edward A. Startsev, and Ronald C. Davidson Plasma Physics Laboratory, Princeton University, Princeton

Kaganovich, Igor

134

Princeton Plasma Physics Laboratory Annual Site Environmental Report for Calendar Year 1999  

SciTech Connect (OSTI)

The results of the 1999 environmental surveillance and monitoring program for the Princeton Plasma Physics Laboratory (PPPL) are presented and discussed. The purpose of this report is to provide the U.S. Department of Energy and the public with information on the level of radioactive and non-radioactive pollutants (if any) that are added to the environment as a result of PPPL's operations. The report also summarizes environmental initiatives, assessments, and programs that were undertaken in 1999. The Princeton Plasma Physics Laboratory has engaged in fusion energy research since 1951. The long-range goal of the U.S. Magnetic Fusion Energy Research Program is to create innovations to make fusion power a practical reality--an alternative energy source. 1999 marked the first year of National Spherical Torus Experiment (NSTX) operations and Tokamak Fusion Test Reactor (TFTR) dismantlement and deconstruction activities. A collaboration among fourteen national laboratories, universities, and research institutions, the NSTX is a major element in the U.S. Fusion Energy Sciences Program. It has been designed to test the physics principles of spherical torus (ST) plasmas. The ST concept could play an important role in the development of smaller, more economical fusion reactors. With its completion within budget and ahead of its target schedule, NSTX first plasma occurred on February 12, 1999. The 1999 performance of the Princeton Plasma Physics Laboratory was rated ''outstanding'' by the U.S. Department of Energy in the Laboratory Appraisal report issued early in 2000. The report cited the Laboratory's consistently excellent scientific and technological achievements, its successful management practices, and included high marks in a host of other areas including environmental management, employee health and safety, human resources administration, science education, and communications. Groundwater investigations continued under a voluntary agreement with the New Jersey Department of Environmental Protection. PPPL monitored for the presence of non-radiological contaminants, mainly volatile organic compounds (components of degreasing solvents). Monitoring revealed the presence of low levels of volatile organic compounds in an area adjacent to PPPL. Also, PPPL's radiological monitoring program characterized the ambient, background levels of tritium in the environment and from the TFTR stack; the data are presented in this report.

Virginia Finley

2001-04-20T23:59:59.000Z

135

Princeton Plasma Physics Laboratory Annual Site Environmental Report for Calendar Year 1996  

SciTech Connect (OSTI)

The results of the 1996 environmental surveillance and monitoring program for the Princeton Plasma Physics Laboratory (PPPL) are presented and discussed. The purpose of this report is to provide the US Department of Energy and the public with information on the level of radioactive and nonradioactive pollutants, if any, that are added to the environment as a result of PPPL's operations. During Calendar Year 1996, PPPL's Tokamak Fusion Test Reactor (TFTR) continued to conduct fusion experiments. Having set a world record on November 2, 1994, by achieving approximately 10.7 million watts of controlled fusion power during the deuterium-tritium (D-T) plasma experiments, researchers turned their attention to studying plasma science experiments, which included ''enhanced reverse shear techniques.'' Since November 1993, more than 700 tritium-fueled experiments were conducted, which generated more than 4 x 10(superscript 20) neutrons and 1.4 gigajoules of fusion energy. In 1996, the overall performance of Princeton Plasma Physics Laboratory was rated ''excellent'' by the US Department of Energy in the Laboratory Appraisal report issued in early 1997. The report cited the Laboratory's consistently excellent scientific and technological achievements and its successful management practices, which included high marks for environmental management, employee health and safety, human resources administration, science education, and communications. Groundwater investigations continued under a voluntary agreement with the New Jersey Department of Environmental Protection. PPPL monitored for the presence of nonradiological contaminants, mainly volatile organic compounds (components of degreasing solvents) and petroleum hydrocarbons (past leaks of releases of diesel fuel from underground storage tanks). Also, PPPL's radiological monitoring program characterized the ambient, background levels of tritium in the environment and from the TFTR stack; the data are presented in this report. During 1996, PPPL completed the removal of contaminated soil from two locations that were identified through the monitoring program: petroleum hydrocarbons along a drainage swale and chromium adjacent to the cooling tower.

J.D. Levine; V.L. Finley

1998-03-01T23:59:59.000Z

136

Electronically swept millimetre-wave interferometer for spatially resolved measurement of plasma electron  

E-Print Network [OSTI]

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

Howard, John

137

Heavy Ion Fusion Science Virtual National Laboratory 1st Quarter FY08 Milestone Report: Report Initial Work on Developing Plasma Modeling Capability in WARP for NDCX Experiments Report Initial work on developing Plasma Modeling Capability in WARP for NDCX Experiments  

E-Print Network [OSTI]

plasma and (b) just past the time of peak compression and focus.plasma simulation models in Warp is to enable simulations of neutralized longitudinal compression and focuscm -3 at focus. The base case examined has a plasma density

Friedman, A.

2008-01-01T23:59:59.000Z

138

Application of soft X-ray lasers for probing high density plasmas  

SciTech Connect (OSTI)

The reliability and characteristics of collisionally pumped soft x-ray lasers make them ideal for a wide variety of plasma diagnostics. These systems now operate over a wavelength range extending from 35 to 400 {Angstrom} and have output energies as high as 10 mJ in 150 ps pulses. The beam divergence of these lasers is less than 15 mrad and they have a typical linewidth of {Delta}{lambda}/{lambda} {approximately} 10{sup -4} making them the brightest xuv sources available. In this paper we will describe the use of x-ray lasers to probe high density plasmas using a variety of diagnostic techniques. Using an x-ray laser and a multilayer mirror imaging system we have studied hydrodynamic imprinting of laser speckle pattern on directly driven thin foils with 1-2 {mu}m spatial resolution. Taking advantage of recently developed multilayer beamsplitters we have constructed and used a Mach-Zehnder interferometer operating at 155 {Angstrom} to probe 1-3 mm size laser produced plasmas with peak electron densities of 4 x 10{sup 21} cm{sup -3}. A comparison of our results with computer simulations will be presented.

Da Silva, L.B.; Barbee, T.W. Jr.; Cauble, R. [and others

1996-08-01T23:59:59.000Z

139

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

DOE Patents [OSTI]

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.

Thode, Lester E. (Los Alamos, NM)

1981-01-01T23:59:59.000Z

140

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

SciTech Connect (OSTI)

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.

Chen, Hui, E-mail: chen33@llnl.gov, E-mail: bitter@pppl.gov; Magee, E.; Nagel, S. R.; Park, J.; Schneider, M. B.; Stone, G.; Williams, G. J.; Beiersdorfer, P. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550-9234 (United States); Bitter, M., E-mail: chen33@llnl.gov, E-mail: bitter@pppl.gov; Hill, K. W. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Kerr, S. [Department of Applied Science, University of Alberta, Edmonton, Alberta T6G 2R3 (Canada)

2014-11-15T23:59:59.000Z

Note: This page contains sample records for the topic "density laboratory plasmas" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

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

SciTech Connect (OSTI)

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.

Lin, M.-W.; Jovanovic, I. [Department of Mechanical and Nuclear Engineering, Pennsylvania State University, University Park, Pennsylvania 16802 (United States)

2012-11-15T23:59:59.000Z

142

Two photon absorption laser induced fluorescence measurements of neutral density in a helicon plasma  

SciTech Connect (OSTI)

We have developed a new diagnostic based on two-photon absorption laser induced fluorescence (TALIF). We use a high intensity (5?MW/cm{sup 2}), narrow bandwidth (0.1?cm{sup ?1}) laser to probe the ground state of neutral hydrogen, deuterium and krypton with spatial resolution better than 0.2?cm, a time resolution of 10?ns, and a measurement cadence of 20?Hz. Here, we describe proof-of-principle measurements in a helicon plasma source that demonstrate the TALIF diagnostic is capable of measuring neutral densities spanning four orders of magnitude; comparable to the edge neutral gradients predicted in the DIII-D tokamak pedestal. The measurements are performed in hydrogen and deuterium plasmas and absolute calibration is accomplished through TALIF measurements in neutral krypton. The optical configuration employed is confocal, i.e., both light injection and collection are accomplished with a single lens through a single optical port in the vacuum vessel. The wavelength resolution of the diagnostic is sufficient to separate hydrogen and deuterium spectra and we present measurements from mixed hydrogen and deuterium plasmas that demonstrate isotopic abundance measurements are feasible. Time resolved measurements also allow us to explore the evolution of the neutral hydrogen density and temperature and effects of wall recycling. We find that the atomic neutral density grows rapidly at the initiation of the discharge, reaching the steady-state value within 1?ms. Additionally, we find that neutral hydrogen atoms are born with 0.08?eV temperatures, not 2?eV as is typically assumed.

Galante, M. E.; Magee, R. M.; Scime, E. E. [Department of Physics, West Virginia University, Morgantown, West Virginia 26506 (United States)] [Department of Physics, West Virginia University, Morgantown, West Virginia 26506 (United States)

2014-05-15T23:59:59.000Z

143

Nonlinear Modulated Envelope Electrostatic Wavepacket Propagation in Space and Laboratory Plasmas  

SciTech Connect (OSTI)

A brief review of the occurrence of amplitude modulated structures in space and laboratory plasmas is provided, followed by a theoretical analysis of the mechanism of carrier wave (self-) interaction, with respect to electrostatic plasma modes. A generic collisionless unmagnetized fluid model is employed. Both cold-(zero-temperature) and warm-(finite temperature) fluid descriptions are considered and compared. The weakly nonlinear oscillation regime is investigated by applying a multiple scale (reductive perturbation) technique and a Nonlinear Schroedinger Equation (NLSE) is obtained, describing the evolution of the slowly varying wave amplitude in time and space. The amplitude's stability profile reveals the possibility of modulational instability to occur under the influence of external perturbations. The NLSE admits exact localized envelope (solitary wave) solutions of bright (pulses) or dark (holes, voids) type, whose characteristics depend on intrinsic plasma parameters. The role of perturbation obliqueness (with respect to the propagation direction), finite temperature and -- possibly -- defect (dust) concentration is explicitly considered. The relevance of this description with respect to known electron-ion (e-i) as well as dusty (complex) plasma modes is briefly discussed.

Kourakis, Ioannis; Shukla, Padma Kant [Institut fuer Theoretische Physik IV, Fakultaet fuer Physik und Astronomie, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany)

2004-12-01T23:59:59.000Z

144

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

E-Print Network [OSTI]

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.

Guiyun Liang; Gang Zhao

2008-03-14T23:59:59.000Z

145

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

E-Print Network [OSTI]

1 Effect of shockwave-induced density jump on laser plasma interactions in low-pressure ambient air jump were investigated in low- pressure ambient air during the laser pulse using an optical interferometer. A tiny shockwave-induced density jump could be observed clearly in ambient air with pressure

Tillack, Mark

146

Princeton Plasma Physics Laboratory (PPPL) annual site environmental report for Calendar Year 1992  

SciTech Connect (OSTI)

This report gives the results of the environmental activities and monitoring programs at the Princeton Plasma Physics Laboratory (PPPL) for CY92. The report is prepared to provide the US Department of Energy (DOE) and the public with information on the level of radioactive and nonradioactive pollutants, if any, added to the environment as a result of PPPL operations, as well as environmental initiatives, assessments, and programs. The objective of the Annual Site Environmental Report is to document evidence that DOE facility environmental protection programs adequately protect the environment and the public health.

Finley, V.L.; Wieczorek, M.A.

1994-03-01T23:59:59.000Z

147

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched5 IndustrialIsadore Perlman,Bios HighRadiobiology:Princeton Plasma Physics Laboratory

148

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

SciTech Connect (OSTI)

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.

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)

2014-03-15T23:59:59.000Z

149

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

E-Print Network [OSTI]

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 motion 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 fomula 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.

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

2012-02-17T23:59:59.000Z

150

Laboratory studies of spectroscopic markers for the characterization of surface erosion by plasmas  

SciTech Connect (OSTI)

The erosion rates in portions of fusion plasma devices like the ITER tokamak are sufficiently high that nearly real-time information on cumulative removal is needed for control and machine safety. We are developing a digitally--encoded scheme to indicate the depth of erosion at numerous poloidal and toroidal locations around ITER. The scheme uses materials embedded in the walls and divertors, which, when uncovered, present remotely detectable signals. This paper reports laboratory experiments on prototype markers consisting of combinations of up to 5 elements (Au,Pd,Ag,In,Ga) along with Au,Pt, and Ta pure metals. The markers were bonded to 4-D carbon-carbon composite of the type proposed for use in the ITER first wall, and placed in the lower-hybrid-driven plasma of the atomic beam facility at PPL. The paper describes this device Light emission was characterized using a 1 meter Czerny-Turner vacuum ultraviolet monochromator. The samples were characterized both before and after plasma exposure by Auger spectroscopy. We report the time-dependent behavior of the spectra of the visible and ultraviolet light emitted by the plasma when the markers are uncovered by the erosion showing emission lines of the marker elements which are easily distinguished from the background plasma lines. The dependence of the light intensity on bias voltage is compared to the known sputtering yields of the elements. The optical detection method allows exploration of the threshold dependence of these multi-element targets. An exponential dependence of yield above threshold was observed for all of the elements studied.

Manos, D.M.; Bennett, T.; Herzer, M.; Schwarzmann, J.

1992-06-01T23:59:59.000Z

151

Laboratory studies of spectroscopic markers for the characterization of surface erosion by plasmas  

SciTech Connect (OSTI)

The erosion rates in portions of fusion plasma devices like the ITER tokamak are sufficiently high that nearly real-time information on cumulative removal is needed for control and machine safety. We are developing a digitally--encoded scheme to indicate the depth of erosion at numerous poloidal and toroidal locations around ITER. The scheme uses materials embedded in the walls and divertors, which, when uncovered, present remotely detectable signals. This paper reports laboratory experiments on prototype markers consisting of combinations of up to 5 elements (Au,Pd,Ag,In,Ga) along with Au,Pt, and Ta pure metals. The markers were bonded to 4-D carbon-carbon composite of the type proposed for use in the ITER first wall, and placed in the lower-hybrid-driven plasma of the atomic beam facility at PPL. The paper describes this device Light emission was characterized using a 1 meter Czerny-Turner vacuum ultraviolet monochromator. The samples were characterized both before and after plasma exposure by Auger spectroscopy. We report the time-dependent behavior of the spectra of the visible and ultraviolet light emitted by the plasma when the markers are uncovered by the erosion showing emission lines of the marker elements which are easily distinguished from the background plasma lines. The dependence of the light intensity on bias voltage is compared to the known sputtering yields of the elements. The optical detection method allows exploration of the threshold dependence of these multi-element targets. An exponential dependence of yield above threshold was observed for all of the elements studied.

Manos, D.M.; Bennett, T.; Herzer, M.; Schwarzmann, J.

1992-01-01T23:59:59.000Z

152

Princeton Plasma Physics Laboratory Annual Site Environmental Report for Calendar Year 2000  

SciTech Connect (OSTI)

The results of the 2000 environmental surveillance and monitoring program for the Princeton Plasma Physics Laboratory (PPPL) are presented and discussed. The purpose of this report is to provide the U.S. Department of Energy and the public with information on the level of radioactive and nonradioactive pollutants (if any) that are added to the environment as a result of PPPL's operations. The report also summarizes environmental initiatives, assessments, and programs that were undertaken in 2000. The Princeton Plasma Physics Laboratory has engaged in fusion energy research since 1951. The long-range goal of the U.S. Magnetic Fusion Energy Research Program is to create innovations to make fusion power a practical reality -- an alternative energy source. The year 2000 marked the second year of National Spherical Torus Experiment (NSTX) operations and Tokamak Fusion Test Reactor (TFTR) dismantlement and deconstruction activities. A collaboration among fourteen national laboratories, universities, and research institutions, the NSTX is a major element in the U.S. Fusion Energy Sciences Program. It has been designed to test the physics principles of spherical torus (ST) plasmas. The ST concept could play an important role in the development of smaller, more economical fusion power plants. With its completion within budget and ahead of its target schedule, NSTX first plasma occurred on February 12, 1999. In 2000, PPPL's radiological environmental monitoring program measured tritium in the air at on-site and off-site sampling stations. PPPL is capable of detecting small changes in the ambient levels of tritium by using highly sensitive monitors. The operation of an in-stack monitor located on D-site is a requirement of the National Emission Standard for Hazardous Air Pollutants (NESHAPs) regulations with limits set by the Environmental Protection Agency (EPA). Also included in PPPL's radiological environmental monitoring program, are precipitation, surface, ground, a nd waste water monitoring. Groundwater investigations continued under a voluntary agreement with the New Jersey Department of Environmental Protection. PPPL monitored for the presence of nonradiological contaminants, mainly volatile organic compounds (components of degreasing solvents). Monitoring revealed the presence of low levels of volatile organic compounds in an area adjacent to PPPL. Also, PPPL's radiological monitoring program characterized the ambient, background levels of tritium in the environment and from the D-site stack; the data are presented in this report.

Virginia L. Finley

2002-04-22T23:59:59.000Z

153

Diagnosing ions and neutrals via n=2 excited hydrogen atoms in plasmas with high electron density and low electron temperature  

SciTech Connect (OSTI)

Ion and neutral parameters are determined in the high electron density, magnetized, hydrogen plasma beam of an ITER divertor relevant plasma via measurements of the n=2 excited neutrals. Ion rotation velocity (up to 7 km/s) and temperature (2-3 eV{approx}T{sub e}) are obtained from analysis of H{alpha} spectra measured close to the plasma source. The methodology for neutral density determination is explained whereby measurements in the linear plasma beam of Pilot-PSI are compared to modeling. Ground-state atomic densities are obtained via the production rate of n=2 and the optical thickness of the Lyman-{alpha} transition (escape factor {approx}0.6) and yield an ionization degree >85% and dissociation degree in the residual gas of {approx}4%. A 30% proportion of molecules with a rovibrational excitation of more than 2 eV is deduced from the production rate of n=2 atoms. This proportion increases by more than a factor of 4 for a doubling of the electron density in the transition to ITER divertor relevant electron densities, probably because of a large increase in the production and confinement of ground-state neutrals. Measurements are made using laser-induced fluorescence (LIF) and absorption, the suitability of which are evaluated as diagnostics for this plasma regime. Absorption is found to have a much better sensitivity than LIF, mainly owing to competition with background emission.

Shumack, A. E.; Schram, D. C.; Biesheuvel, J.; Goedheer, W. J.; Rooij, G. J. van [FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, Trilateral Euregio Cluster, Nieuwegein (Netherlands)

2011-03-15T23:59:59.000Z

154

Present Status and Future Prospects of Laser Fusion and Related High Energy Density Plasma Research  

SciTech Connect (OSTI)

The present status and future prospects of the laser fusion research and related laser plasma physics are reviewed. In laser fusion research, giant lasers for ignition and burn by imploding DT fuel pellets are under construction at LLNL (Lawrence Livermore National Laboratory) and CEA, France. In Japan , the Gekko XII and the Peta Watt laser system have been operated to investigate the implosion hydrodynamics, fast ignition, and the relativistic laser plasma interactions and a new project; FIREX( Fast Ignition Realization Experiment) had started toward the ignition and burn at the Institute of laser Engineering of Osaka University. Recently, heating experiments with cone shell target have been carried out. The thermal neutron yield is found to increase by three orders of magnitude by the peta watt laser injection to the cone shell target. The FIREX-I is planned according to this experimental results, where multi 10kJ peta watt laser is used to heat compressed DT fuel to the ignition temperature. The FIREX-II will follow for demonstrating ignition and burn, in which the implosion laser and heating laser are up-graded.

Mima, Kunioki [Institute of Laser Engineering, Osaka University, 2-6 Yamada-oka, Suita , Osaka, 565-0871 (Japan)

2004-12-01T23:59:59.000Z

155

Measurements of electron density and temperature in the H-1 heliac plasma by helium line intensity ratios  

SciTech Connect (OSTI)

Electron density and temperature distributions in the H-1 heliac plasma are measured using the helium line intensity ratio technique based on a collisional-radiative model. An inversion approach with minimum Fisher regularization is developed to reconstruct the ratios of the local emission radiances from detected line-integrated intensities. The electron density and temperature inferred from the He I 667.8/728.1 and He I 728.1/706.5 nm line ratios are in good agreement with those from other diagnostic techniques in the inner region of the plasma. The electron density and temperature values appear to be a little high in the outer region of the plasma. Some possible causes of the discrepancy in the outer region are discussed.

Ma Shuiliang; Howard, John; Blackwell, Boyd D.; Thapar, Nandika [Plasma Research Laboratory, Australian National University, Canberra ACT 0200 (Australia)

2012-03-15T23:59:59.000Z

156

DENSITY AND MAGNETIC FIELD MEASUREMENTS IN THE TORMAC IV-c PLASMA  

E-Print Network [OSTI]

1974). R.B. Lovberg, in Plasma Diagnostic Techniques, R.H.the plasma using "non-ambiguous" diagnostics. There has beenand the plasma in contact with the wall. Diagnostics Tonnac

Coonrod Jr., John Walter

2011-01-01T23:59:59.000Z

157

Wavefront-sensor-based electron density measurements for laser-plasma accelerators  

E-Print Network [OSTI]

for laser-plasma accelerators G. R. Plateau, ? N. H. Matlis,driven plasma-wake?eld accelerator depends on the plasmaof the laser-plasma accelerator. It is shown that direct

Plateau, Guillaume

2010-01-01T23:59:59.000Z

158

Measurements of neutral density profiles using a deuterium Balmer-alpha diagnostic in the C-2 FRC plasma  

SciTech Connect (OSTI)

In C-2 field-reversed configuration (FRC) device, low neutral density outside the FRC separatrix is required to minimize the charge exchange loss of fast particles. Titanium gettering is used in C-2 to reduce the wall recycling and keep the neutral density low in plasma edge. The measurements of neutral density radial profile are desirable to understand the plasma recycling and the effects of titanium gettering. These measurements are also needed to study the interaction of neutral beams with FRC plasma and confinement of fast ions. Diagnostic based on absolute deuterium Balmer-alpha (D-alpha) radiation measurements is developed and deployed on C-2 device to measure the radial profile of neutral density. Simultaneous measurements of electron density and temperature are done using CO{sub 2} interferometer, Thomson scattering, and triple probes diagnostics along with absolute D-alpha radiation. Abel inversion was performed to get the time dependent radial profile of the local D-alpha emission density. Neutral density profiles are obtained under different machine conditions of titanium deposition.

Gupta, Deepak K.; Deng, B. H.; Knapp, K.; Sun, X.; Thompson, M. C. [Tri Alpha Energy, Rancho Santa Margarita, California 92688 (United States)

2012-10-15T23:59:59.000Z

159

Wavefront-sensor-based electron density measurements for laser-plasma accelerators  

E-Print Network [OSTI]

After imaging the plasma to a primary focus shortly afterfocus was 1 mm above the nozzle. The laser pulse excited a plasma

Plateau, Guillaume

2010-01-01T23:59:59.000Z

160

Ecological environment of the proposed site for the Compact Ignition Tokamak at Princeton Plasma Physics Laboratory  

SciTech Connect (OSTI)

This report gives a description of the exological environment of D-site and the surrounding area at Princeton Plasma Physics Laboratory (PPPL) near Princeton, New Jersey. D-site at PPL is the proposed location for construction of a new fusion test facility, the Compact Ignition Tokamak (CIT). This report was prepared as supplemental information for an Environmental Assessment for the proposed CIT at PPL. The report characterizes the vegetation and wildlife occuring at and near the site and describes the water quality and aquatic ecology of Bee Brook. No threatened or endangered plant or animal species are known to occur in the area, although suitable habitat exists for some species. The occurrence of a forested wetland north of the site is discussed. 9 refs., 2 figs.

Not Available

1987-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "density laboratory plasmas" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
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161

FY93 Princeton Plasma Physics Laboratory. Annual report, October 1, 1992--September 30, 1993  

SciTech Connect (OSTI)

This is the annual report from the Princeton Plasma Physics Laboratory for the period October 1, 1992 to September 30, 1993. The report describes work done on TFTR during the year, as well as preparatory to beginning of D-T operations. Design work is ongoing on the Tokamak Physics Experiment (TPX) which is to test very long pulse operations of tokamak type devices. PBX has come back on line with additional ion-Bernstein power and lower-hybrid current drive. The theoretical program is also described, as well as other small scale programs, and the growing effort in collaboration on international design projects on ITER and future collaborations at a larger scale.

Not Available

1995-02-01T23:59:59.000Z

162

Environmental Survey preliminary report, Princeton Plasma Physics Laboratory, Princeton, New Jersey  

SciTech Connect (OSTI)

This report presents the preliminary findings of the first phase of the Environmental Survey of the United States Department of Energy's (DOE) Princeton Plasma Physics Laboratory (PPPL), conducted June 13 through 17, 1988. The Survey is being conducted by an interdisciplinary team of environmental specialists, led and managed by the Office of Environment, Safety and Health's Office of Environmental Audit. Team members are being provided by private contractors. The objective of the Survey is to identify environmental problems and areas of environmental risk associated with PPPL. The Survey covers all environmental media and all areas of environmental regulation. It is being performed in accordance with the DOE Environmental Survey Manual. This phase of the Survey involves the review of existing site environmental data, observations of the operations carried on at PPPL, and interviews with site personnel. The Survey team developed a Sampling and Analysis (S A) Plan to assist in further assessing certain of the environment problems identified during its on-site activities. The S A plan is being developed by the Idaho National Engineering Laboratory. When completed, the S A results will be incorporated into the PPPL Survey findings for inclusion in the Environmental Survey Summary Report. 70 refs., 17 figs., 21 tabs.

Not Available

1989-05-01T23:59:59.000Z

163

Prepared for the U.S. Department of Energy under Contract DE-AC02-76CH03073. Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

, and K. Indireshkumar September 2005 PRINCETON PLASMA PHYSICS LABORATORY PPPL PPPL-4101 PPPL-4101 #12.S. Department of Energy's Princeton Plasma Physics Laboratory Publications and Reports web site in Fiscal Year the potential to provide very long pulses and significant neutron fluence if the physics regime can be produced

164

A passive measurement of dissociated atom densities in atmospheric pressure air discharge plasmas using vacuum ultraviolet self-absorption spectroscopy  

SciTech Connect (OSTI)

We demonstrate a method for determining the dissociation degree of atmospheric pressure air discharges by measuring the self-absorption characteristics of vacuum ultraviolet radiation from O and N atoms in the plasma. The atom densities are determined by modeling the amount of radiation trapping present in the discharge, without the use of typical optical absorption diagnostic techniques which require external sources of probing radiation into the experiment. For an 8.0?mm spark discharge between needle electrodes at atmospheric pressure, typical peak O atom densities of 8.5?×?10{sup 17}?cm{sup ?3} and peak N atom densities of 9.9?×?10{sup 17}?cm{sup ?3} are observed within the first ?1.0?mm of plasma near the anode tip by analyzing the OI and NI transitions in the 130.0–132.0?nm band of the vacuum ultraviolet spectrum.

Laity, George [Center for Pulsed Power and Power Electronics, Department of Electrical and Computer Engineering and Department of Physics, Texas Tech University, Lubbock, Texas 79409 (United States); Applied Science and Technology Maturation Department, Sandia National Laboratories, Albuquerque, New Mexico 87123 (United States); Fierro, Andrew; Dickens, James; Neuber, Andreas [Center for Pulsed Power and Power Electronics, Department of Electrical and Computer Engineering and Department of Physics, Texas Tech University, Lubbock, Texas 79409 (United States); Frank, Klaus [Erlangen Centre for Astroparticle Physics, Department of Physics, Friedrich–Alexander University at Erlangen-Nürnberg, 91058 Erlangen (Germany)

2014-03-28T23:59:59.000Z

165

Bulk ion acceleration and particle heating during magnetic reconnection in a laboratory plasma  

SciTech Connect (OSTI)

Bulk ion acceleration and particle heating during magnetic reconnection are studied in the collisionless plasma of the Magnetic Reconnection Experiment (MRX). The plasma is in the two-fluid regime, where the motion of the ions is decoupled from that of the electrons within the ion diffusion region. The reconnection process studied here is quasi-symmetric since plasma parameters such as the magnitude of the reconnecting magnetic field, the plasma density, and temperature are compatible on each side of the current sheet. Our experimental data show that the in-plane (Hall) electric field plays a key role in ion heating and acceleration. The electrostatic potential that produces the in-plane electric field is established by electrons that are accelerated near the electron diffusion region. The in-plane profile of this electrostatic potential shows a “well” structure along the direction normal to the reconnection current sheet. This well becomes deeper and wider downstream as its boundary expands along the separatrices where the in-plane electric field is strongest. Since the in-plane electric field is 3–4 times larger than the out-of-plane reconnection electric field, it is the primary source of energy for the unmagnetized ions. With regard to ion acceleration, the Hall electric field causes ions near separatrices to be ballistically accelerated toward the outflow direction. Ion heating occurs as the accelerated ions travel into the high pressure downstream region. This downstream ion heating cannot be explained by classical, unmagnetized transport theory; instead, we conclude that ions are heated by re-magnetization of ions in the reconnection exhaust and collisions. Two-dimensional (2-D) simulations with the global geometry similar to MRX demonstrate downstream ion thermalization by the above mechanisms. Electrons are also significantly heated during reconnection. The electron temperature sharply increases across the separatrices and peaks just outside of the electron diffusion region. Unlike ions, electrons acquire energy mostly from the reconnection electric field, and the energy gain is localized near the X-point. However, the increase in the electron bulk flow energy remains negligible. These observations support the assertion that efficient electron heating mechanisms exist around the electron diffusion region and that the heat generated there is quickly transported along the magnetic field due to the high parallel thermal conductivity of electrons. Classical Ohmic dissipation based on the perpendicular Spitzer resistivity is too small to balance the measured heat flux, indicating the presence of anomalous electron heating.

Yoo, Jongsoo; Yamada, Masaaki; Ji, Hantao; Jara-Almonte, Jonathan; Myers, Clayton E. [Center for Magnetic Self-Organization, Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)] [Center for Magnetic Self-Organization, Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)

2014-05-15T23:59:59.000Z

166

Prepared for the U.S. Department of Energy under Contract DE-AC02-76CH03073. Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

, California 92186 3 Columbia University, New York, New York 10027 Abstract Plasma shape control using realPrepared for the U.S. Department of Energy under Contract DE-AC02-76CH03073. Princeton Plasma is posted on the U.S. Department of Energy's Princeton Plasma Physics Laboratory Publications and Reports

167

Prepared for the U.S. Department of Energy under Contract DE-AC02-76CH03073. Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

;#12;#12;#12;#12;#12;#12;#12;#12;#12;External Distribution 05/16/05 Plasma Research Laboratory, Australian National University, Australia, Hungary Dr. P. Kaw, Institute for Plasma Research, India Ms. P.J. Pathak, Librarian, Institute for Plasma Research, India Dr. Pandji Triadyaksa, Fakultas MIPA Universitas Diponegoro, Indonesia Professor Sami

168

Prepared for the U.S. Department of Energy under Contract DE-AC02-76CH03073. Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

@adonis.osti.gov #12;#12;#12;#12;#12;#12;#12;External Distribution 05/16/05 Plasma Research Laboratory, Australian Research Institute for Physics, Hungary Dr. P. Kaw, Institute for Plasma Research, India Ms. P.J. Pathak, Librarian, Institute for Plasma Research, India Dr. Pandji Triadyaksa, Fakultas MIPA Universitas Diponegoro

169

ANALYSIS OF DATA FROM Z-PINCH MTF TARGET PLASMA EXPERIMENTS  

SciTech Connect (OSTI)

The Los Alamos National Laboratory Colt facility has been used to create target plasma for Magnetized Target Fusion (MTF). The primary results regarding magnetic field, plasma density, plasma temperature, and hot plasma lifetime are summarized and the suitability of these plasma targets for MTF is assessed.

F. WYSOCKI; J. TACCETTI; ET AL

1999-04-01T23:59:59.000Z

170

CO{sub 2} laser-based dispersion interferometer utilizing orientation-patterned gallium arsenide for plasma density measurements  

SciTech Connect (OSTI)

A dispersion interferometer based on the second-harmonic generation of a carbon dioxide laser in orientation-patterned gallium arsenide has been developed for measuring electron density in plasmas. The interferometer includes two nonlinear optical crystals placed on opposite sides of the plasma. This instrument has been used to measure electron line densities in a pulsed radio-frequency generated argon plasma. A simple phase-extraction technique based on combining measurements from two successive pulses of the plasma has been used. The noise-equivalent line density was measured to be 1.7 × 10{sup 17} m{sup ?2} in a detection bandwidth of 950 kHz. One of the orientation-patterned crystals produced 13 mW of peak power at the second-harmonic wavelength from a carbon dioxide laser with 13 W of peak power. Two crystals arranged sequentially produced 58 mW of peak power at the second-harmonic wavelength from a carbon dioxide laser with 37 W of peak power.

Bamford, D. J.; Cummings, E. A.; Panasenko, D. [Physical Sciences Inc., 6652 Owens Drive, Pleasanton, California 94588 (United States)] [Physical Sciences Inc., 6652 Owens Drive, Pleasanton, California 94588 (United States); Fenner, D. B.; Hensley, J. M. [Physical Sciences Inc., 20 New England Business Center, Andover, Massachusetts 01810 (United States)] [Physical Sciences Inc., 20 New England Business Center, Andover, Massachusetts 01810 (United States); Boivin, R. L.; Carlstrom, T. N.; Van Zeeland, M. A. [General Atomics, P.O. Box 85608, San Diego, California 92186 (United States)] [General Atomics, P.O. Box 85608, San Diego, California 92186 (United States)

2013-09-15T23:59:59.000Z

171

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

SciTech Connect (OSTI)

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.

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)

2013-08-15T23:59:59.000Z

172

Princeton Plasma Physics Laboratory Report PPPL-3319 1 of 18 Core Transport Reduction in Tokamak Plasmas with  

E-Print Network [OSTI]

energy production. PACS numbers: 52.55.Fa, 52.55.Dy, 52.55.-s, 52.35.Ra * email contact: MBell, however, probably first seen in plasmas fueled by the injection of frozen deuterium pellets. The Pellet

173

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)

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.

Bokaei, B.; Niknam, A. R., E-mail: a-niknam@sbu.ac.ir [Laser and Plasma Research Institute, Shahid Beheshti University, G.C., Tehran (Iran, Islamic Republic of)

2014-03-15T23:59:59.000Z

174

Numerical solutions of sheath structures in front of an electron-emitting electrode immersed in a low-density plasma  

SciTech Connect (OSTI)

The exact theoretical expressions involved in the formation of sheath in front of an electron emitting electrode immersed in a low-density plasma have been derived. The potential profile in the sheath region has been calculated for subcritical, critical, and supercritical emissions. The potential profiles of critical and supercritical emissions reveals that we must take into account a small, instead of zero, electric field at the sheath edge to satisfy the boundary conditions used to integrate the Poisson's equation. The I-V curves for critical emission shows that only high values of plasma-electron to emitted-electron temperature ratio can meet the floating potential of the emissive electrode. A one-dimensional fluid like model is assumed for ions, while the electron species are treated as kinetic. The distribution of emitted-electron from the electrode is assumed to be half Maxwellian. The plasma-electron enters the sheath region at sheath edge with half Maxwellian velocity distribution, while the reflected ones have cut-off velocity distribution due to the absorption of super thermal electrons by the electrode. The effect of varying emitted-electron current on the sheath structure has been studied with the help of a parameter G (the ratio of emitted-electron to plasma-electron densities)

Din, Alif [Theoretical Plasma Physics Division, PINSTECH, P. O. Nilore, 44000 Islamabad (Pakistan)] [Theoretical Plasma Physics Division, PINSTECH, P. O. Nilore, 44000 Islamabad (Pakistan)

2013-09-15T23:59:59.000Z

175

Temperature and density evolution during decay in a 2.45 GHz hydrogen electron cyclotron resonance plasma: Off-resonant and resonant cases  

SciTech Connect (OSTI)

Time resolved electron temperature and density measurements during the decay stage in a hydrogen electron cyclotron resonance (ECR) plasma are presented for a resonance and off-resonance magnetic field configurations. The measurements are conducted on a ECR plasma generator excited at 2.45 GHz denominated test-bench for ion-sources plasma studies at ESS Bilbao. The plasma parameters evolution is studied by Langmuir probe diagnostic with synchronized sample technique developed for repetitive pulsed plasmas with a temporal resolution of 200 ns in typical decay processes of about 40 ?s. An afterglow transient is clearly observed in the reflected microwave power signal from the plasma. Simultaneously, the electron temperature evolution shows rebounding peaks that may be related to the interplay between density drop and microwave coupling with deep impact on the Electron Energy Distribution Function. The correlation of such structures with the plasma absorbed power and the coupling quality is also reported.

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

2013-09-15T23:59:59.000Z

176

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

SciTech Connect (OSTI)

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.

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

2014-08-15T23:59:59.000Z

177

Excitation of electrostatic waves in the electron cyclotron frequency range during magnetic reconnection in laboratory overdense plasmas  

SciTech Connect (OSTI)

We report the observation of electromagnetic radiation at high harmonics of the electron cyclotron frequency that was considered to be converted from electrostatic waves called electron Bernstein waves (EBWs) during magnetic reconnection in laboratory overdense plasmas. The excitation of EBWs was attributed to the thermalization of electrons accelerated by the reconnection electric field around the X-point. The radiative process discussed here is an acceptable explanation for observed radio waves pulsation associated with major flares.

Kuwahata, A., E-mail: kuwahata@ts.t.u-tokyo.ac.jp [Graduate School of Engineering, The University of Tokyo, Tokyo 113-8656 (Japan); Igami, H. [National Institute for Fusion Science, Toki 509-5292 (Japan); Kawamori, E. [Institute of Space and Plasma Sciences, National Cheng Kung University, Tainan 70101, Taiwan (China); Kogi, Y. [Fukuoka Institute of Technology, Fukuoka 811-0295 (Japan); Inomoto, M.; Ono, Y. [Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa 277-8561 (Japan)

2014-10-15T23:59:59.000Z

178

Princeton University Plasma Physics Laboratory, Princeton, New Jersey. Annual report, October 1, 1990--September 30, 1991  

SciTech Connect (OSTI)

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.

Not Available

1991-12-31T23:59:59.000Z

179

Innovation Hubs Kendall Square as Laboratory for High-Density Urban Living  

E-Print Network [OSTI]

% of total energy consumption. It is a global imperative to develop systems that improve the livability of cities while dramatically reducing resource consumption. This workshop will explore new urban systems for high-density cities including systems for mobility, energy, food production, and live

180

Plasma-Density Determination from X-Ray Radiography of Laser-Driven Spherical Implosions  

E-Print Network [OSTI]

The fuel layer density of an imploding laser-driven spherical shell is inferred from framed x-ray radiographs. The density distribution is determined by using Abel inversion to compute the radial distribution of the opacity ...

Frenje, Johan A.

Note: This page contains sample records for the topic "density laboratory plasmas" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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We encourage you to perform a real-time search of NLEBeta
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181

Princeton Plasma Physics Laboratory Report PPPL3319 1 of 18 Core Transport Reduction in Tokamak Plasmas with  

E-Print Network [OSTI]

energy production. PACS numbers: 52.55.Fa, 52.55.Dy, 52.55.­s, 52.35.Ra * email contact: MBell, however, probably first seen in plasmas fueled by the injection of frozen deuterium pellets. The Pellet

182

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

E-Print Network [OSTI]

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, ...

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

2012-01-01T23:59:59.000Z

183

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

E-Print Network [OSTI]

Lawrence Livermore National Laboratory American Association for the Advancement of Science February 13 Lawrence Livermore National Laboratory under contract No. W-7405-Eng-48. #12;Tabak Snowmass We are making be tested at the National Ignition Facility(NIF) · NIF is scheduled for completion by 2009 ­ Physics

184

5. Kodama, R. et al. Fast heating of ultrahigh-density plasma as a step towards laser fusion ignition. Nature 412, 798802 (2001).  

E-Print Network [OSTI]

5. Kodama, R. et al. Fast heating of ultrahigh-density plasma as a step towards laser fusion. J. Geophys. Res. 100, 23567­23581 (1995). 13. Hirahara, M. et al. Acceleration and heating of cold

Davis, James C.

185

Nanoparticle manipulation in the near-substrate areas of low-temperature, high-density rf plasmas  

SciTech Connect (OSTI)

Manipulation of a single nanoparticle in the near-substrate areas of high-density plasmas of low-temperature glow discharges is studied. It is shown that the nanoparticles can be efficiently manipulated by the thermophoretic force controlled by external heating of the substrate stage. Particle deposition onto or repulsion from nanostructured carbon surfaces critically depends on the values of the neutral gas temperature gradient in the near-substrate areas, which is directly measured in situ in different heating regimes by originally developed temperature gradient probe. The measured values of the near-surface temperature gradient are used in the numerical model of nanoparticle dynamics in a variable-length presheath. Specific conditions enabling the nanoparticle to overcome the repulsive potential and deposit on the substrate during the discharge operation are investigated. The results are relevant to fabrication of various nanostructured films employing structural incorporation of the plasma-grown nanoparticles, in particular, to nanoparticle deposition in the plasma-enhanced chemical-vapor deposition of carbon nanostructures in hydrocarbon-based plasmas.

Rutkevych, P.P.; Ostrikov, K.; Xu, S. [Plasma Sources and Applications Center, National Institute of Education (NIE), Nanyang Technological University, 1 Nanyang Walk, Singapore 637616 (Singapore); School of Physics, The University of Sydney, Sydney, New South Wales 2006 (Australia); Plasma Sources and Applications Center, National Institute of Education (NIE), Nanyang Technological University, 1 Nanyang Walk, Singapore 637616 (Singapore)

2005-10-01T23:59:59.000Z

186

Prepared for the U.S. Department of Energy under Contract DE-AC02-76CH03073. Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

Prepared for the U.S. Department of Energy under Contract DE-AC02-76CH03073. Princeton Plasma Availability Princeton Plasma Physics Laboratory This report is posted on the U.S. Department of Energy to U.S. Department of Energy and its contractors, in paper from: U.S. Department of Energy Office

187

Prepared for the U.S. Department of Energy under Contract DE-AC02-76CH03073. Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

Physics Laboratory Global Hybrid Simulations of Energetic Particle-driven Modes in Toroidal Plasmas G://www.ntis.gov/ordering.htm #12;Global Hybrid Simulations of Energetic Particle-driven Modes in Toroidal Plasmas G. Y. Fu 1), J, Princeton, NJ 08543, U.S.A. 2) New York University, New York, NY e-mail: fu@pppl.gov Abstract Global hybrid

188

meeting of the NSTX Program Advisory Committee Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

of Fusion Energy Sciences (OFES) held a series of Research Needs Workshops (ReNeW) to identify research-performance, steady-state plasmas", "Taming the plasma material interface (PMI)", "Harnessing fusion power) for particle pumping, higher-power fast-wave heating for current ramp-up studies and electron heating

Princeton Plasma Physics Laboratory

189

Testimony of Dr. Stewart C. Prager Director, Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

by the justcompleted study by the U.S. fusion community, commissioned by DOE and known as the Re international ITER experiment. A fusion system consists of the hot plasma core ­ the "sun on earth" in which to control the 100 million degree plasma core is quite amazing. Yet, we have more work to do

190

Prepared for the U.S. Department of Energy under Contract DE-AC02-76CH03073. Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

Physics Laboratory Global Hybrid Simulations of Energetic Particle Effects on the n=1 Mode in Tokamaks://www.ntis.gov/ordering.htm #12;Global hybrid simulations of energetic particle effects on the n=1 mode in tokamaks: internal kink.E. Sugiyamac aPrinceton Plasma Physics Laboratory, Princeton, New Jersey 08543 b New York University, New York

191

Propagation of a cloud of hot electrons through a plasma in the presence of Langmuir scattering by ambient density fluctuations  

SciTech Connect (OSTI)

Gas-dynamic theory is generalized to incorporate the effects of beam-driven Langmuir waves scattering off ambient density fluctuations, and the consequent effects on the propagation of a cloud of hot electrons in an inhomogeneous plasma. Assuming Langmuir scattering as the limit of nonlinear three-wave interactions with fluctuations that are weak, low-frequency, long-wavelength ion-sound waves, the net effect of scattering is equivalent to effective damping of the Langmuir waves. Under the assumption of self-similarity in the evolution of the beam and Langmuir wave distribution functions, gas-dynamic theory shows that the effects of Langmuir scattering on the beam distribution are equivalent to a perturbation in the injection profile of the beam. Analytical expressions are obtained for the height of the plateau of the beam distribution function, wave spectral number density, total wave and particle energy density, and the beam number density. The main results of gas-dynamic theory are then compared with simulation results from numerical solutions of quasilinear equations. The relaxation of the beam in velocity space is retarded in the presence of density fluctuations and the magnitude of the upper velocity boundary is less than that in the absence of fluctuations. There are four different regimes for the height of the plateau, corresponding to different stages of relaxation of the beam in velocity space. Moreover, Langmuir scattering results in transfer of electrons from moderate velocity to low velocity; this effect produces an enhancement in the beam number density at small distances near the injection site and a corresponding decrease at large distances. There are sharp decreases in the profiles of the beam and total wave energy densities, which are related to dissipation of energy at large phase velocities. Due to a slower velocity space diffusion of the beam distribution in the presence of scattering effects, the spatial width of the beam is reduced while its mean velocity of propagation increases slightly.

Foroutan, G. R.; Robinson, P. A.; Sobhanian, S.; Moslehi-Fard, M.; Li, B.; Cairns, I. H. [School of Physics, University of Sydney, NSW 2006, Sydney (Australia); Research Institute for Astronomy and Astrophysics of Maragha, P.O. Box 55134-441 Maragha (Iran, Islamic Republic of) and Physics Department, Faculty of Science, Sahand University of Technology, 51335-1996 Tabriz (Iran); School of Physics, University of Sydney, NSW 2006, Sydney (Australia); Research Institute for Astronomy and Astrophysics of Maragha, P.O. Box 55134-441 Maragha (Iran, Islamic Republic of) and Faculty of Physics, Tabriz University, Tabriz 51664 (Iran); Faculty of Physics, Tabriz University, Tabriz 51664 (Iran, Islamic Republic of); School of Physics, University of Sydney, NSW 2006, Sydney (Australia)

2007-01-15T23:59:59.000Z

192

Laboratory  

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193

Laboratory  

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

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194

Laboratory  

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

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195

Influence of ambient gas on the temperature and density of laser produced carbon plasma  

E-Print Network [OSTI]

; accepted for publication 11 November 1997 The effect of ambient gas on the dynamics of the plasma generated In moderate or high pressures, a blast wave model is found to describe accurately the plume propagation the maximum plume length with considerable accuracy.7,13 In this letter we report the effect of ambient

Harilal, S. S.

196

Princeton Plasma Physics Laboratory annual report, October 1, 1991--September 30, 1992  

SciTech Connect (OSTI)

This report discusses the following topics: Principal parameters achieved in experimental devices for fiscal year 1992; tokamak fusion test reactor; princeton beta experiment-modification; current drive experiment-upgrade; tokamak physics experiment/steady-state advanced tokamak; international thermonuclear experimental reactor; international collaboration; x-ray laser studies; plasma processing: Deposition and etching of thin films; pure electron plasma experiments; theoretical studies; tokamak modeling; high-field magnet project; engineering department; environment, safety, and health and quality assurance; technology transfer; office of human resources and administration; PPPL invention disclosures for fiscal year 1992; office of resource management; graduate education: plasma physics; graduate education: program in plasma science and technology; and science education program.

Not Available

1992-12-31T23:59:59.000Z

197

Alfvén wave collisions, the fundamental building block of plasma turbulence. IV. Laboratory experiment  

SciTech Connect (OSTI)

Turbulence is a phenomenon found throughout space and astrophysical plasmas. It plays an important role in solar coronal heating, acceleration of the solar wind, and heating of the interstellar medium. Turbulence in these regimes is dominated by Alfvén waves. Most turbulence theories have been established using ideal plasma models, such as incompressible MHD. However, there has been no experimental evidence to support the use of such models for weakly to moderately collisional plasmas which are relevant to various space and astrophysical plasma environments. We present the first experiment to measure the nonlinear interaction between two counterpropagating Alfvén waves, which is the building block for astrophysical turbulence theories. We present here four distinct tests that demonstrate conclusively that we have indeed measured the daughter Alfvén wave generated nonlinearly by a collision between counterpropagating Alfvén waves.

Drake, D. J. [Department of Physics, Astronomy, and Geosciences, Valdosta State University, Valdosta, Georgia 31698 (United States)] [Department of Physics, Astronomy, and Geosciences, Valdosta State University, Valdosta, Georgia 31698 (United States); Schroeder, J. W. R.; Howes, G. G.; Kletzing, C. A.; Skiff, F. [Department of Physics and Astronomy, University of Iowa, Iowa City, Iowa 52242 (United States)] [Department of Physics and Astronomy, University of Iowa, Iowa City, Iowa 52242 (United States); Carter, T. A.; Auerbach, D. W. [Department of Physics and Astronomy, University of California, Los Angeles, California 90095 (United States)] [Department of Physics and Astronomy, University of California, Los Angeles, California 90095 (United States)

2013-07-15T23:59:59.000Z

198

Princeton Plasma Physics Laboratory annual report, October 1, 1982-September 30, 1983  

SciTech Connect (OSTI)

The Tokamak Fusion Test Reactor (TFTR) achieved first plasma at 3:05 a.m. on December 24, 1982. During the course of the year, the plasma current was raised to a maximum of 1 MA, and extensive confinement studies were carried out with ohmic-heated plasmas. The most important finding was that tokamak energy confinement time increases as the cube of the plasma size. The Princeton Large Torus (PLT) carried out a number of high-powered plasma-heating experiments in the ion cyclotron frequency range, and also demonstrated for the first time that a 100-kA tokamak discharge can be built up by means of rf-waves in the lower hybrid range, without any need for inductive current drive by the conventional tokamak transformer system. The Poloidal Divertor Experiment (PDX) demonstrated that substantial improvements in plasma confinement during intense neutral-beam heating can be obtained by means of either a magnetic divertor or a mechanical scoop limiter. The S-1 spheromak experiment has come into operation, with first plasma in January 1983, and machine completion in August. The soft X-ray laser development experiment continues to make strong progress towards the demonstration of laser amplification. Thus far, a single-pass gain of 3.5 has been achieved, using the 182 A line of CVI. Theoretical MHD-stability studies have shed new light on the nature of the energetic-ion-driven ''fishbone instability,'' and the utilization of the bean-shaping technique to reach higher beta values in the tokamak.

Phillips, C.A. (ed.)

1983-01-01T23:59:59.000Z

199

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

SciTech Connect (OSTI)

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.

Weller, M. E., E-mail: mweller@unr.edu; 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. [Physics Department, University of Nevada, Reno, Nevada 89557 (United States)] [Physics Department, University of Nevada, Reno, Nevada 89557 (United States); Apruzese, J. P.; Giuliani, J. L. [Naval Research Laboratory, Washington, District of Columbia 20375 (United States)] [Naval Research Laboratory, Washington, District of Columbia 20375 (United States); Chuvatin, A. S. [Ecole Polytechnique, 91128 Palaiseau (France)] [Ecole Polytechnique, 91128 Palaiseau (France)

2014-03-15T23:59:59.000Z

200

Electron density inside Enceladus plume inferred from plasma oscillations excited by dust impacts  

E-Print Network [OSTI]

1 Department of Physics and Astronomy, University of Iowa, Iowa City, Iowa, USA, 2 LASP, University and electron spectrometers [Jones et al., 2009; Hill et al., 2012]. The nanoparticles appear as high-energy a sweeping voltage, and the ion and electron density can be inferred from the current balance. It is found

Gurnett, Donald A.

Note: This page contains sample records for the topic "density laboratory plasmas" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Electron density estimations derived from spacecraft potential measurements on Cluster in tenuous plasma regions  

E-Print Network [OSTI]

in the solar wind, the magnetosheath, and the plasmashere by the use of CIS ion density and WHISPER electron, in operation from early 2001 in a high inclination orbit, have provided data over nearly half of the 11-year are in the magnetotail from approximately beginning of July to end of October, and the high inclination orbit makes

California at Berkeley, University of

202

PPPL PRINCETON PLASMA PHYSICS LABORATORY TERMS & CONDITIONS FOR COMMERCIAL ITEMS OR SERVICES  

E-Print Network [OSTI]

) "Agreement" means Purchase Order, Subcontract, Price Agreement, Basic Ordering Agreement, or any mod by Princeton for DOE under Prime Contract No. DE-AC02-09CH11466. (f) "Princeton" means the Trustees orders and agreements for commer- cial items or services awarded by Princeton University Plasma Physics

203

Analytical and Numerical Studies of the Complex Interaction of a Fast Ion Beam Pulse with a Background Plasma  

E-Print Network [OSTI]

]. In this paper, we focus on the nonlinear case where the plasma density has an arbitrary value compared with a Background Plasma Igor D. Kaganovich1 , Edward A. Startsev1 and Ronald C. Davidson1 1 Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543, USA Received September 8, 2003 Abstract Plasma

Kaganovich, Igor

204

Imaging spectroscopy diagnosis of internal electron temperature and density distributions of plasma cloud surrounding hydrogen pellet in the Large Helical Device  

SciTech Connect (OSTI)

To investigate the behavior of hydrogen pellet ablation, a novel method of high-speed imaging spectroscopy has been used in the Large Helical Device (LHD) for identifying the internal distribution of the electron density and temperature of the plasma cloud surrounding the pellet. This spectroscopic system consists of a five-branch fiberscope and a fast camera, with each objective lens having a different narrow-band optical filter for the hydrogen Balmer lines and the background continuum radiation. The electron density and temperature in the plasma cloud are obtained, with a spatial resolution of about 6 mm and a temporal resolution of 5 Multiplication-Sign 10{sup -5} s, from the intensity ratio measured through these filters. To verify the imaging, the average electron density and temperature also have been measured from the total emission by using a photodiode, showing that both density and temperature increase with time during the pellet ablation. The electron density distribution ranging from 10{sup 22} to 10{sup 24} m{sup -3} and the temperature distribution around 1 eV have been observed via imaging. The electron density and temperature of a 0.1 m plasma cloud are distributed along the magnetic field lines and a significant electron pressure forms in the plasma cloud for typical experimental conditions of the LHD.

Motojima, G.; Sakamoto, R.; Goto, M.; Matsuyama, A.; Yamada, H. [National Institute for Fusion Science, 322-6, Oroshi-cho, Toki-City, Gifu 509-5292 (Japan); Mishra, J. S. [Graduate University for Advanced Studies, 322-6, Oroshi-cho, Toki-City, Gifu 509-5292 (Japan)

2012-09-15T23:59:59.000Z

205

Scattering of Radio Frequency Waves by Edge Density Blobs in Tokamak Plasmas  

SciTech Connect (OSTI)

The density blobs and fluctuations present in the edge region of magnetic fusion devices can scatter radio frequency (RF) waves through refraction and diffraction. The scattering can diffuse the rays in space and in wave-vector space. The diffusion in space can make the rays miss their intended target region, while the diffusion in wave-vector space can broaden the wave spectrum and modify the wave damping and current profile.

Ram, A. K. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Hizanidis, K.; Kominis, Y. [National Technical University of Athens, Association EURATOM-Hellenic Republic, Zografou, Athens 15773 (Greece)

2011-12-23T23:59:59.000Z

206

Effect of Screening on Thermonuclear Fusion in Stellar and Laboratory Plasmas  

E-Print Network [OSTI]

The fusion enhancement factor due to screening in the solar plasma is calculated. We use the finite temperature Green's function method and a self consistent mean field approximation. We reduce this to one center problems, because in the collision of two fusing ions, the turning point where tunneling may occur lies far inside the screening radius. The numerical results given by this method indicate that screening may be slightly weaker than that obtained in the most recent previous calculations.

L. Wilets; B. G. Giraud; M. J. Watrous; J. J. Rehr

1999-06-21T23:59:59.000Z

207

Laboratory studies of the dynamic of resonance cones formation in magnetized plasmas  

SciTech Connect (OSTI)

The paper is devoted to experimental studies of formation of resonance cones in magnetized plasmas by pulsed RF source in the lower-hybrid (whistler) and the upper-hybrid frequency ranges. It is shown that in both frequency ranges, resonance cones exhibit similar dynamics after switching-on the RF source: at first, wide maxima of radiation are formed in non-resonance directions, which then become narrower, with their direction approaching the resonance one. While the resonance cones are being formed, one observes a fine structure in the form of secondary radiation maxima. It is shown that the characteristic formation time of stationary resonance cones is determined by the minimal value of the group velocity of the quasi-electrostatic waves excited by the antenna. In the low-temperature plasma, this value is limited in the lower-hybrid frequency range by the spatial spectrum of the emitting antenna and in the upper-hybrid range, by the effects of spatial plasma dispersion.

Nazarov, V. V.; Starodubtsev, M. V.; Kostrov, A. V. [Russian Academy of Sciences, Institute of Applied Physics, Nizhny Novgorod (Russian Federation)

2013-03-15T23:59:59.000Z

208

CPLA non conference publications Center for Plasma in the Laboratory and  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-Series to someone6Energy, science,PrinciplesPlasma&CONTIUATIN NO.Astrophysics

209

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

Office of Science (SC) Website

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210

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched5 IndustrialIsadore Perlman,Bios HighRadiobiology:Princeton Plasma PhysicsPrinceton

211

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched5 IndustrialIsadoreConnecticutPhotos of AEC Site Under ConstructionPrinceton Plasma

212

Proceedings of the eighth international colloquium on ultraviolet and x-ray spectroscopy of astrophysical and laboratory plasmas (IAU colloquium 86)  

SciTech Connect (OSTI)

This volume represents the Proceedings of the Eighth International Colloquium on Ultraviolet and X-Ray Spectroscopy of Astrophysical and Laboratory Plasmas. The aim of this series of colloquia has been to bring together workers in the fields of astrophysical spectroscopy, laboratory spectroscopy and atomic physics in order to exchange ideas and results on problems which are common to these different disciplines. In addition to the presented papers there was a poster paper session. (WRF)

Not Available

1984-01-01T23:59:59.000Z

213

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

SciTech Connect (OSTI)

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.

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)

2014-11-15T23:59:59.000Z

214

Quark spectral density and a strongly-coupled quark-gluon plasma.  

SciTech Connect (OSTI)

The maximum entropy method is used to compute the dressed-quark spectral density from the self-consistent numerical solution of a rainbow truncation of QCD's gap equation at temperatures above that for which chiral symmetry is restored. In addition to the normal and plasmino modes, the spectral function also exhibits an essentially nonperturbative zero mode for temperatures extending to 1.4-1.8 times the critical temperature, T{sub c}. In the neighborhood of T{sub c}, this long-wavelength mode contains the bulk of the spectral strength and as long as this mode persists, the system may fairly be described as a strongly-coupled state of matter.

Qin, S.; Chang, L.; Liu, Y.; Roberts, C. D. (Physics); (Peking Univ.); (Inst. of Applied Physics and Computational Mathematics); (National Lab. of Heavy Ion Accelerator)

2011-07-13T23:59:59.000Z

215

Experimental Study of the Hall Effect and Electron Diffusion Region During Magnetic Reconnection in a Laboratory Plasma  

SciTech Connect (OSTI)

The Hall effect during magnetic reconnection without an external guide field has been extensively studied in the laboratory plasma of the Magnetic Reconnection Experiment (MRX) [Yamada et al., Phys. Plasmas 4, 1936 (1997)] by measuring its key signature, an out-of-plane quadrupole magnetic field, with magnetic probe arrays whose spatial resolution is on the order of the electron skin depth. The in-plane electron flow is deduced from out-of-plane magnetic field measurements. The measured in-plane electron flow and numerical results are in good agreement. The electron diffusion region is identified by measuring the electron outflow channel. The width of the electron diffusion region scales with the electron skin depth (~ 8c/?pe) and the peak electron outflow velocity scales with the electron Alfven velocity (~ 0:11VeA), independent of ion mass. The measured width of the electron diffusion region is much wider and the observed electron outflow is much slower than those obtained in 2D numerical simulations. It is found that the classical and anomalous dissipation present in the experiment can broaden the electron diffusion region and slow the electron outflow. As a consequence, the electron outflow flux remain consistent with numerical simulations. The ions, as measured by a Mach probe, have a much wider outflow channel than the electrons, and their outflow is much slower than the electron outflow everywhere in the electron diffusion region.

Ren, Yang; Yamada, Masaaki; Ji, Hantao; Dorfman, Seth; Gerhardt, Stefan; Kulsrud, Russel

2008-07-02T23:59:59.000Z

216

Beta-dependent upper bound on ion temperature anisotropy in a laboratory plasma  

SciTech Connect (OSTI)

Laser induced fluorescence measurements of ion temperatures, parallel and perpendicular to the local magnetic field, in the Large Experiment on Instabilities and Anisotropies space simulation chamber (a steady-state, high beta, argon plasma) display an inverse correlation between the upper bound on the ion temperature anisotropy and the parallel ion beta ({beta}=8{pi}nkT/B{sup 2}). These observations are consistent with in situ spacecraft measurements in the Earth's magnetosheath and with a theoretical/computational model that predicts that such an upper bound is imposed by scattering from enhanced fluctuations due to growth of the ion cyclotron anisotropy instability (the Alfven ion cyclotron instability). (c) 2000 American Institute of Physics.

Keiter, Paul A. [West Virginia University, Morgantown, West Virginia 26506 (United States)] [West Virginia University, Morgantown, West Virginia 26506 (United States); Scime, Earl E. [West Virginia University, Morgantown, West Virginia 26506 (United States)] [West Virginia University, Morgantown, West Virginia 26506 (United States); Balkey, Matthew M. [West Virginia University, Morgantown, West Virginia 26506 (United States)] [West Virginia University, Morgantown, West Virginia 26506 (United States); Boivin, Robert [West Virginia University, Morgantown, West Virginia 26506 (United States)] [West Virginia University, Morgantown, West Virginia 26506 (United States); Kline, John L. [West Virginia University, Morgantown, West Virginia 26506 (United States)] [West Virginia University, Morgantown, West Virginia 26506 (United States); Gary, S. Peter [Los Alamos National Laboratory, Los Alamos, New Mexico 87544 (United States)] [Los Alamos National Laboratory, Los Alamos, New Mexico 87544 (United States)

2000-03-01T23:59:59.000Z

217

Princeton Plasma Physics Laboratory annual report, October 1, 1993-- September 30, 1994  

SciTech Connect (OSTI)

The Tokamak Fusion Test Reactor (TFTR) project is well into the experimental phase of its deuterium-tritium (D-T) program, with the objective to derive the maximum amount of experimental data on the behavior of tokamak plasmas containing a significant population of energetic alpha particles. Since the initial D-T experiments in December 1993, the operational performance of the TFTR, as well as the required tritium-handling and machine maintenance procedures in an activated environment, have improved markedly, so that D-T operation has now become essentially routine, while fully conforming with all of the safety and environmental requirements. During the D-T phase, the machine and auxiliary-systems parameters have also been increased, most notably the toroidal field (to 5.6 T) and the neutral-beam power (to 40 MW). The radio-frequency power in the ion-cyclotron-range of frequencies (ICRF) has been increased to 11 MW.

NONE

1994-12-31T23:59:59.000Z

218

Final Report: Laboratory Studies of Spontaneous Reconnection and Intermittent Plasma Objects  

SciTech Connect (OSTI)

The study of the collisionless magnetic reconnection constituted the primary work carried out under this grant. The investigations utilized two magnetic configurations with distinct boundary conditions. Both configurations were based upon the Versatile Toroidal Facility (VTF) at the MIT Plasma Science and Fusion Center and the MIT Physics Department. The NSF/DOE award No. 0613734, supported two graduate students (now Drs. W. Fox and N. Katz) and material expenses. The grant enabled these students to operate the VTF basic plasma physics experiment on magnetic reconnection. The first configuration was characterized by open boundary conditions where the magnetic field lines interface directly with the vacuum vessel walls. The reconnection dynamics for this configuration has been methodically characterized and it has been shown that kinetic effects related to trapped electron trajectories are responsible for the high rates of reconnection observed. This type of reconnection has not been investigated before. Nevertheless, the results are directly relevant to observations by the Wind spacecraft of fast reconnection deep in the Earth magnetotail. The second configuration was developed to be relevant to specifically to numerical simulations of magnetic reconnection, allowing the magnetic field-lines to be contained inside the device. The configuration is compatible with the presence of large current sheets in the reconnection region and reconnection is observed in fast powerful bursts. These reconnection events facilitate the first experimental investigations of the physics governing the spontaneous onset of fast reconnection. In the Report we review the general motivation of this work and provide an overview of our experimental and theoretical results enabled by the support through the awards.

Egedal-Pedersen, Jan [Massachusetts Institute of Technology; Porkolab, Miklos [Massachusetts Institute of Technology

2011-05-31T23:59:59.000Z

219

Prepared for the U.S. Department of Energy under Contract DE-AC02-76CH03073. Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

for plasma boundary control [D. A. Gates, etal., submitted to Nuclear Fusion (2005)]. More recently Physics Laboratory Status of the Control System on the National Spherical Torus Experiment (NSTX) D://www.ntis.gov/ordering.htm #12;Status of the Control System on the National Spherical Torus Experiment (NSTX) D. A. Gatesa , J. R

220

Very low friction for diamond sliding on diamond in water Plasma Processing Laboratory, Auburn University, 200 Broun Hall, Auburn, Alabama 36849  

E-Print Network [OSTI]

on a polished polycrystalline chemically vapor deposited diamond film in water at a speed of 0.05 mm/s underVery low friction for diamond sliding on diamond in water Y. Tzeng Plasma Processing Laboratory for publication 17 September 1993) This letter reports the lowest coefficient of friction measured for diamond

Tzeng, Yonhua

Note: This page contains sample records for the topic "density laboratory plasmas" from the National Library of EnergyBeta (NLEBeta).
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221

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

SciTech Connect (OSTI)

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

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

2014-02-15T23:59:59.000Z

222

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)

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. %.

Niemi, K.; O'Connell, D.; Gans, T. [York Plasma Institute, Department of Physics, University of York, York YO10 5DD (United Kingdom); Oliveira, N. de; Joyeux, D.; Nahon, L. [Synchrotron Soleil, l'Orme des Merisiers, St. Aubin BP 48, 91192 Gif sur Yvette Cedex (France); Booth, J. P. [Laboratoire de Physique des Plasmas-CNRS, Ecole Polytechnique, 91128 Palaiseau (France)

2013-07-15T23:59:59.000Z

223

Reduction of plasma density in the Helicity Injected Torus with Steady Inductance experiment by using a helicon pre-ionization source  

SciTech Connect (OSTI)

A helicon based pre-ionization source has been developed and installed on the Helicity Injected Torus with Steady Inductance (HIT-SI) spheromak. The source initiates plasma breakdown by injecting impurity-free, unmagnetized plasma into the HIT-SI confinement volume. Typical helium spheromaks have electron density reduced from (2–3) × 10{sup 19} m{sup ?3} to 1 × 10{sup 19} m{sup ?3}. Deuterium spheromak formation is possible with density as low as 2 × 10{sup 18} m{sup ?3}. The source also enables HIT-SI to be operated with only one helicity injector at injector frequencies above 14.5 kHz. A theory explaining the physical mechanism driving the reduction of breakdown density is presented.

Hossack, Aaron C.; Jarboe, Thomas R.; Victor, Brian S. [Department of Aeronautics and Astronautics, University of Washington, Seattle, Washington 98195 (United States)] [Department of Aeronautics and Astronautics, University of Washington, Seattle, Washington 98195 (United States); Firman, Taylor; Prager, James R.; Ziemba, Timothy [Eagle Harbor Technologies, Inc., 119 W. Denny Way, Suite 210, Seattle, Washington 98119 (United States)] [Eagle Harbor Technologies, Inc., 119 W. Denny Way, Suite 210, Seattle, Washington 98119 (United States); Wrobel, Jonathan S. [979B West Moorhead Circle, Boulder, Colorado 80305 (United States)] [979B West Moorhead Circle, Boulder, Colorado 80305 (United States)

2013-10-15T23:59:59.000Z

224

australian radiation laboratory: Topics by E-print Network  

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

Plasma Physics Laboratory Plasma Physics and Fusion Websites Summary: 1605 Plasma Research Laboratory, Australian National University, Australia Professor I.R. Jones,...

225

Ultrafast dynamics of a near-solid-density layer in an intense femtosecond laser-excited plasma  

SciTech Connect (OSTI)

We report on the picosecond dynamics of a near-solid-density plasma generated by an intense, infrared (??=?800?nm) femtosecond laser using time-resolved pump-probe Doppler spectrometry. An initial red-shift is observed in the reflected third harmonic (??=?266?nm) probe pulse, which gets blue-shifted at longer probe-delays. A combination of particle-in-cell and radiation-hydrodynamics modelling is performed to model the pump laser interaction with the solid target. The results are post-processed to predict the Doppler shift. An excellent agreement is found between the results of such modelling and the experiment. The modelling suggests that the initial inward motion of the critical surface observed in the experiment is due to the passage of a shock-wave-like disturbance, launched by the pump interaction, propagating into the target. Furthermore, in order to achieve the best possible fit to the experimental data, it was necessary to incorporate the effects of bulk ion-acceleration resulting from the electrostatic field set up by the expulsion of electrons from the laser envelope. We also present results of time-resolved pump-probe reflectometry, which are corroborated with the spectrometry results using a 1-D reflectivity model.

Adak, Amitava; Chatterjee, Gourab; Kumar Singh, Prashant; Lad, Amit D.; Brijesh, P.; Kumar, G. Ravindra, E-mail: grk@tifr.res.in [Tata Institute of Fundamental Research, Dr. Homi Bhabha Road, Colaba, Mumbai 400005 (India); Blackman, David R. [York Plasma Institute, University of York, Heslington, York YO10 5DQ (United Kingdom); Robinson, A. P. L. [Central Laser Facility, Rutherford-Appleton Laboratory, Chilton, Didcot OX10 0QX (United Kingdom); Pasley, John [York Plasma Institute, University of York, Heslington, York YO10 5DQ (United Kingdom); Central Laser Facility, Rutherford-Appleton Laboratory, Chilton, Didcot OX10 0QX (United Kingdom)

2014-06-15T23:59:59.000Z

226

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)

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.

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)

2014-02-21T23:59:59.000Z

227

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

E-Print Network [OSTI]

844 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 34, NO. 3, JUNE 2006 Energy Balance and Plasma, and Zoltan Sternovsky Abstract--Electron energy balance is shown to play an impor- tant role in determining that satisfy the energy balance equation. The ion loss rate af- fects the electron loss rate through the quasi

Kaganovich, Igor

228

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)

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.

Prevosto, L.; Mancinelli, B. [Grupo de Descargas Electricas, Departamento Ing. Electromecanica, Facultad Regional Venado Tuerto (UTN), Laprida 651, Venado Tuerto 2600, Santa Fe (Argentina); Artana, G. [Laboratorio de Fluidodinamica, Departamento Ing. Mecanica, Facultad de Ingenieria (UBA), Paseo Colon 850, C1063ACV, Buenos Aires (Argentina); Kelly, H. [Grupo de Descargas Electricas, Departamento Ing. Electromecanica, Facultad Regional Venado Tuerto (UTN), Laprida 651, Venado Tuerto 2600, Santa Fe (Argentina); Departamento de Fisica, Facultad de Ciencias Exactas y Naturales (UBA), Instituto de Fisica del Plasma (CONICET), Ciudad Universitaria, Pab. I, 1428 Buenos Aires (Argentina)

2011-03-15T23:59:59.000Z

229

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

SciTech Connect (OSTI)

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.

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)

2014-12-15T23:59:59.000Z

230

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

SciTech Connect (OSTI)

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.

Habibi, M., E-mail: habibi.physics@gmail.com [Young Researchers and Elite Club, Shirvan Branch, Islamic Azad University, Shirvan (Iran, Islamic Republic of); Ghamari, F. [Young Researchers and Elite Club, Khorramabad Branch, Islamic Azad University, Khorramabad (Iran, Islamic Republic of)

2014-05-15T23:59:59.000Z

231

Numerical and laboratory simulations of auroral acceleration  

SciTech Connect (OSTI)

The existence of parallel electric fields is an essential ingredient of auroral physics, leading to the acceleration of particles that give rise to the auroral displays. An auroral flux tube is modelled using electrostatic Vlasov simulations, and the results are compared to simulations of a proposed laboratory device that is meant for studies of the plasma physical processes that occur on auroral field lines. The hot magnetospheric plasma is represented by a gas discharge plasma source in the laboratory device, and the cold plasma mimicking the ionospheric plasma is generated by a Q-machine source. In both systems, double layers form with plasma density gradients concentrated on their high potential sides. The systems differ regarding the properties of ion acoustic waves that are heavily damped in the magnetosphere, where the ion population is hot, but weakly damped in the laboratory, where the discharge ions are cold. Ion waves are excited by the ion beam that is created by acceleration in the double layer in both systems. The efficiency of this beam-plasma interaction depends on the acceleration voltage. For voltages where the interaction is less efficient, the laboratory experiment is more space-like.

Gunell, H.; De Keyser, J. [1Belgian Institute for Space Aeronomy, Avenue Circulaire 3, B-1180 Brussels (Belgium)] [1Belgian Institute for Space Aeronomy, Avenue Circulaire 3, B-1180 Brussels (Belgium); Mann, I. [EISCAT Scientific Association, P.O. Box 812, SE-981 28 Kiruna, Sweden and Department of Physics, Umeå University, SE-901 87 Umeå (Sweden)] [EISCAT Scientific Association, P.O. Box 812, SE-981 28 Kiruna, Sweden and Department of Physics, Umeå University, SE-901 87 Umeå (Sweden)

2013-10-15T23:59:59.000Z

232

Dust density effect on complex plasma decay L. Couedel a,b, A.A. Samarian a  

E-Print Network [OSTI]

and supported by comparison to existing experimental data. Key words: Complex plasma, dust, afterglow, decay (PECVD, etching, fusion reactor,etc). The dust particles are charged due to their interactions, the dust particles can be either grown directly in the plasma chamber (by sputtering [6,7] or using

Paris-Sud XI, Université de

233

Influence of the reactor wall composition on radicals' densities and total pressure in Cl{sub 2} inductively coupled plasmas: II. During silicon etching  

SciTech Connect (OSTI)

In an industrial inductively coupled plasma reactor dedicated to silicon etching in chlorine-based chemistry, the density of Cl{sub 2} molecules and the gas temperature are measured by means of laser absorption techniques, the density of SiCl{sub x} (x{<=}2) radicals by broadband absorption spectroscopy, the density of SiCl{sub 4} and ions by mass spectrometry, and the total gas pressure with a capacitance gauge. These measurements permit us to estimate the mole fractions of Cl, SiCl{sub 4}, and etch product radicals when etching a 200 mm diameter silicon wafer. The pure Cl{sub 2} plasma is operated in well prepared chamber wall coating with a thin film of SiOCl, AlF, CCl, or TiOCl. The impact of the chemical nature of the reactor wall's coatings on these mole fractions is studied systematically. We show that the reactor wall coatings have a huge influence on the radicals densities, but this is not only from the difference on Cl-Cl recombination coefficient on different surfaces. During silicon etching, SiCl{sub x} radicals sticking on the reactor walls are etched by Cl atoms and recycled into the plasma by forming volatile SiCl{sub 4}. Hence, the loss of Cl atoms in etching the wall deposited silicon is at least as important as their wall recombination in controlling the Cl atoms density. Furthermore, because SiCl{sub 4} is produced at high rate by both the wafer and reactor walls, it is the predominant etching product in the gas phase. However, the percentage of redeposited silicon that can be recycled into the plasma depends on the amount of oxygen present in the plasma: O atoms produced by etching the quartz roof window fix Si on the reactor walls by forming a SiOCl deposit. Hence, the higher the O density is, the lower the SiCl{sub 4} density will be, because silicon is pumped by the reactor walls and the SiOCl layer formed is not isotropically etched by chlorine. As a result, in the same pure Cl{sub 2} plasma at 20 mTorr, the SiCl{sub x} mole fraction can vary from 18% in a SiOCl-coated reactor, where the O density is the highest, to 62% in a carbon-coated reactor, where there is no O. In the latter case, most of the Cl mass injected in the reactor is stored in SiCl{sub 4} molecules, which results in a low silicon etch rate. In this condition, the Cl mass balance is verified within 10%, and from the silicon mass balance we concluded that SiCl{sub x} radicals have a high surface loss probability. The impact of the reactor wall coating on the etching process is thus important, but the mechanisms by which the walls control the plasma chemistry is much more complicated than a simple control through recombination reaction of halogen atoms on these surfaces.

Cunge, G.; Sadeghi, N.; Ramos, R. [Laboratoire des Technologies de la Microelectronique, CNRS, 17 rue des Martyrs (c/o CEA-LETI), 38054 Grenoble Cedex 9 (France); Laboratoire de Spectrometrie Physique (UMR 5588), Universite Joseph Fourier-Grenoble, and CNRS, BP 87, 38402 St. Martin d'Heres (France); Laboratoire des Technologies de la Microelectronique, CNRS, 17 rue des Martyrs (c/o CEA-LETI), 38054 Grenoble Cedex 9 (France)

2007-11-01T23:59:59.000Z

234

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)

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.

Young, Bruce Kai Fong

1988-09-01T23:59:59.000Z

235

Influence of the reactor wall composition on radicals' densities and total pressure in Cl{sub 2} inductively coupled plasmas: I. Without silicon etching  

SciTech Connect (OSTI)

Laser absorption at 355 nm is used to monitor the time variations of the Cl{sub 2} density in high-density industrial inductively coupled plasma. This technique is combined with the measurement of the gas temperature from the Doppler width of the 811.5 nm line of argon, added as a trace gas and with the measurement of the total gas pressure with a Baratron gauge. These measurements permit to estimate the mole fractions of Cl{sub 2} and Cl species in Cl{sub 2} inductively coupled plasmas in a waferless reactor. The impact of the chemical nature of the reactor wall coatings on the Cl and Cl{sub 2} mole fractions is studied systematically. We show that under otherwise identical plasma conditions, the Cl mole fraction is completely different when the plasma is operated in SiOCl, AlF, CCl, or TiOCl coated reactors, because the homogeneous recombination probability of Cl atoms is strongly surface dependant. The Cl atom mole fraction reached at 100 W radiofrequency power in SiOCl coated reactor (80%) is much higher than that obtained at 900 W in a ''clean'' AlF reactor (40%). A simple zero-dimensional model permits to provide the recombination coefficient of Cl atoms, {gamma}{sub rec}: 0.005 on SiOCl film and about 0.3 on the other three coatings. It is proposed to get benefit of this very high sensitivity of Cl{sub 2} dissociation rate to the wall coating for the control of the chamber wall status from the Cl{sub 2} density measurements in standard conditions.

Cunge, G.; Sadeghi, N.; Ramos, R. [Laboratoire des Technologies de la Microelectronique, CNRS, 17 rue des Martyrs (c/o CEA-LETI), 38054 Grenoble Cedex 9 (France); Laboratoire de Spectrometrie Physique (UMR 5588), Universite Joseph Fourier-Grenoble, and CNRS, BP 87, 38402 St. Martin d'Heres (France); Laboratoire des Technologies de la Microelectronique, CNRS, 17 rue des Martyrs (c/o CEA-LETI), 38054 Grenoble Cedex 9 (France)

2007-11-01T23:59:59.000Z

236

Quantitative studies of transfer in vivo of low density, Sf 12-60, and Sf 60-400 lipoproteins between plasma and arterial intima in humans  

SciTech Connect (OSTI)

To assess the potential of various plasma lipoprotein classes to contribute to the lipid content of the arterial intima, influx and efflux of these plasma lipoprotein fractions into and from the intima of human carotid arteries were measured in vivo. While low density lipoprotein (LDL) is known to transfer from plasma into the arterial wall, there is less information on the atherogenic potential of lipoproteins of intermediate density (Sf 12-60) or of very low density (Sf 60-400). Aliquots of the same lipoprotein (LDL, Sf 12-60 lipoprotein particles, or Sf 60-400 lipoprotein particles) iodinated with iodine-125 and iodine-131 were injected intravenously 18-29 hours and 3-6 hours, respectively, before elective surgical removal of atheromatous arterial tissue, and the intimal clearance of lipoproteins, lipoprotein influx, and fractional loss of newly entered lipoproteins were calculated. Intimal clearance of Sf 60-400 particles was not detectable (less than 0.3 microliter x hr-1 x cm-2), whereas the average value for both LDL and Sf 12-60 lipoprotein particles was 0.9 microliter x hr-1 x cm-2. Since the fractional loss of newly entered LDL and Sf 12-60 lipoprotein particles was also similar, the results suggest similar modes of entry and exit for these two particles. However, due to lower plasma concentrations of Sf 12-60 lipoproteins as compared with LDL, the mass influx of cholesterol in the Sf 12-60 particles was on the order of one 10th of that in LDL, and that of apolipoprotein B was about one 20th.

Shaikh, M.; Wootton, R.; Nordestgaard, B.G.; Baskerville, P.; Lumley, J.S.; La Ville, A.E.; Quiney, J.; Lewis, B. (Guys Hospital, London, (United Kingdom))

1991-05-01T23:59:59.000Z

237

Instabilities and pattern formation in lowtemperature plasmas  

E-Print Network [OSTI]

of the plasma region is approximately 20cm. (Produced by the Plasma Research Laboratory, Dublin City University

238

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

SciTech Connect (OSTI)

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.

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)

2014-11-15T23:59:59.000Z

239

PLASMA PHYSICS PPPL UC Davis  

E-Print Network [OSTI]

PRINCETON PLASMA PHYSICS LABORATORY PPPL UC Davis PRINCETON PLASMA PHYSICS LABORATORY PPPL UC Davis Scattering System for ETG physics on NSTX H. Park, E. Mazzucato, and D. Smith PPPL, Princeton University C, 2006 Hyatt Regency, Dallas, TX #12;PRINCETON PLASMA PHYSICS LABORATORY PPPL UC Davis PRINCETON PLASMA

240

Far-from-equilibrium dynamics of a strongly coupled non-Abelian plasma with non-zero charge density or external magnetic field  

E-Print Network [OSTI]

Using holography, we study the evolution of a spatially homogeneous, far from equilibrium, strongly coupled N=4 supersymmetric Yang-Mills plasma with a non-zero charge density or a background magnetic field. This gauge theory problem corresponds, in the dual gravity description, to an initial value problem in Einstein-Maxwell theory with homogeneous but anisotropic initial conditions. We explore the dependence of the equilibration process on different aspects of the initial departure from equilibrium and, while controlling for these dependencies, examine how the equilibration dynamics are affected by the presence of a non-vanishing charge density or an external magnetic field. The equilibration dynamics are remarkably insensitive to the addition of even large chemical potentials or magnetic fields; the equilibration time is set primarily by the form of the initial departure from equilibrium. For initial deviations from equilibrium which are well localized in scale, we formulate a simple model for equilibratio...

Fuini, John F

2015-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "density laboratory plasmas" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Far-from-equilibrium dynamics of a strongly coupled non-Abelian plasma with non-zero charge density or external magnetic field  

E-Print Network [OSTI]

Using holography, we study the evolution of a spatially homogeneous, far from equilibrium, strongly coupled N=4 supersymmetric Yang-Mills plasma with a non-zero charge density or a background magnetic field. This gauge theory problem corresponds, in the dual gravity description, to an initial value problem in Einstein-Maxwell theory with homogeneous but anisotropic initial conditions. We explore the dependence of the equilibration process on different aspects of the initial departure from equilibrium and, while controlling for these dependencies, examine how the equilibration dynamics are affected by the presence of a non-vanishing charge density or an external magnetic field. The equilibration dynamics are remarkably insensitive to the addition of even large chemical potentials or magnetic fields; the equilibration time is set primarily by the form of the initial departure from equilibrium. For initial deviations from equilibrium which are well localized in scale, we formulate a simple model for equilibration times which agrees quite well with our results.

John F. Fuini III; Laurence G. Yaffe

2015-03-24T23:59:59.000Z

242

The impact of low-Z impurities on x-ray conversion efficiency from laser-produced plasmas of low-density gold foam targets  

SciTech Connect (OSTI)

It is an important approach to improve the x-ray conversion efficiency of laser-ablated high-Z plasmas by using low initial density materials for various applications. However, unavoidable low-Z impurities in the manufacture process of low-density high-Z foam targets will depress this effect. A general easy-to-use analytical model based on simulations was developed to evaluate the quantitative impact of impurities within the gold foam target on laser to x-ray conversion efficiency. In addition, the x-ray conversion efficiencies of 1 g/cm{sup 3} gold foams with two different initial contents of impurities were experimentally investigated. Good agreements have been achieved between the model results and experiments.

Dong, Yunsong [Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621900 (China) [Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621900 (China); Department of Engineering Physics, Tsinghua University, Beijing 100084 (China); Shang, Wanli; Yang, Jiamin; Zhang, Lu; Zhang, Wenhai; Li, Zhichao; Guo, Liang; Zhan, Xiayu; Du, Huabing; Deng, Bo [Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621900 (China)] [Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621900 (China); Pu, Yikang [Department of Engineering Physics, Tsinghua University, Beijing 100084 (China)] [Department of Engineering Physics, Tsinghua University, Beijing 100084 (China)

2013-12-15T23:59:59.000Z

243

Basic concept in plasma diagnostics  

E-Print Network [OSTI]

This paper presents the basic concept of various plasma diagnostics used for the study of plasma characteristics in different plasma experiments ranging from low temperature to high energy density plasma.

Rai, V N

2014-01-01T23:59:59.000Z

244

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

SciTech Connect (OSTI)

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.

Potanin, E. P., E-mail: potanin@imp.kiae.ru; Ustinov, A. L. [National Research Centre Kurchatov Institute (Russian Federation)

2013-06-15T23:59:59.000Z

245

* Work performed under the auspices of the USDOE by Princeton Plasma Physics Laboratory under Contract No. DEAC0276CH03073.  

E-Print Network [OSTI]

which were integrated for first plasma were Vacuum, Gas Injection, Field Coil Power Conversion operating areas, . acquire, display, and archive digitized waveforms, . import/export process­control values and commands. Conversely, other systems rely on the CPCS to provide the logic, sequencing, and device

246

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)

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.

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)

2014-10-15T23:59:59.000Z

247

TWO DIMENSIONAL COMPUTER SIMULATION OF PLASMA IMMERSION  

E-Print Network [OSTI]

. Barroso and M. Ueda Associated Laboratory of Plasma - LAP National Institute for Space Research - INPE #12

248

A large volume uniform plasma generator for the experiments of electromagnetic wave propagation in plasma  

SciTech Connect (OSTI)

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.

Yang Min; Li Xiaoping; Xie Kai; Liu Donglin [School of Electronical and Mechanical Engineering, Xidian University, Xi'an Shaanxi 710071 (China); Liu Yanming [School of Telecommunications Engineering, Xidian University, Xi'an Shaanxi 710071 (China)

2013-01-15T23:59:59.000Z

249

Modeling the propagation of whistler-mode waves in the presence of field-aligned density irregularities  

E-Print Network [OSTI]

Modeling the propagation of whistler-mode waves in the presence of field-aligned density of VLF whistler-mode waves in a laboratory plasma. Our goal is to understand whistler propagation) whistler in a density enhancement. Results from a numerical simulation of whistler wave propagation

California at Los Angles, University of

250

Opportunities with Laboratories under the Chicago Office  

Broader source: Energy.gov (indexed) [DOE]

Laboratories under the Chicago Office 1 Princeton Plasma Physics Laboratory 1. Mechanical Engineering Services; Larry Dudek; 188,000 2. Phone system; William Bryan; 300,000 3....

251

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

252

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

SciTech Connect (OSTI)

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.

Ju, J.; Döpp, A.; Cros, B. [Laboratoire de Physique des Gaz et des Plasmas, CNRS-Université Paris-Sud, 91405 Orsay (France)] [Laboratoire de Physique des Gaz et des Plasmas, CNRS-Université Paris-Sud, 91405 Orsay (France); Svensson, K.; Genoud, G.; Wojda, F.; Burza, M.; Persson, A.; Lundh, O.; Wahlström, C.-G. [Department of Physics, Lund University, P.O. Box 118, S-22100 Lund (Sweden)] [Department of Physics, Lund University, P.O. Box 118, S-22100 Lund (Sweden); Ferrari, H. [Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) and CNEA-CAB (Argentina)] [Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) and CNEA-CAB (Argentina)

2013-08-15T23:59:59.000Z

253

Boundary Plasma Issues in Burning Plasma Science  

E-Print Network [OSTI]

of operation ) ···· we know a lot more now than during the BPX design! #12;(1) Wide Dispersal of Power plasma/neutral densities · criterion for high recycling and cold divertor, Tt ~ 5 eV (a prerequisite high energy threshold) · interaction at walls of tenuous plasma: 1. how does plasma reach wall? (rapid

Pitcher, C. S.

254

Boundary Plasma Issues in Burning Plasma Science  

E-Print Network [OSTI]

of operation ) · we know a lot more now than during the BPX design! #12;(1) Wide Dispersal of Power plasma/neutral densities · criterion for high recycling and cold divertor, Tt ~ 5 eV (a prerequisite) · interaction at walls of tenuous plasma: 1.how does plasma reach wall? (rapid transport?) 2.can dominate core

255

Laboratories to Explore, Explain VLBACHANDRA  

E-Print Network [OSTI]

Princeton Plasma Physics Laboratory Sandia National Laboratory Stone and Webster The Boeing Company on FIRE and fusion science accessible and up to date. A steady stream of about 150 visitors per week log

256

Plasma Channel Diagnostic Based on Laser Centroid Oscillations  

E-Print Network [OSTI]

plasma density, plasma diagnostics PACS: 52.70.Kz, 52.38.Kd,Plasma Channel Diagnostic Based on Laser Centroid

Gonsalves, Anthony

2012-01-01T23:59:59.000Z

257

Laser Plasma Particle Accelerators: Large Fields for Smaller Facility Sources  

E-Print Network [OSTI]

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

Geddes, Cameron G.R.

2010-01-01T23:59:59.000Z

258

Report of the Interagency Task Force on High Energy Density Physics  

SciTech Connect (OSTI)

Identifies the needs for improving Federal stewardship of specific aspects of high energy density physics, particularly the study of high energy density plasmas in the laboratory, and strengthening university activities in this latter discipline. The report articulates how HEDP fits into the portfolio of federally funded missions and includes agency actions to be taken that are necessary to further this area of study consistent with Federal priorities and plans, while being responsive to the needs of the scientific community.

None

2007-08-01T23:59:59.000Z

259

Autumn College on Plasma Physics, ICTP 2005 Generation and dynamics of large scale flows in magnetized plasmas  

E-Print Network [OSTI]

EURATOM -- Risø National Laboratory Optics and Plasma Research Department, OPL-128 DK-4000 Roskilde

260

Prepared for the U.S. Department of Energy under Contract DE-AC02-76CH03073. Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

;#12;#12;#12;#12;#12;#12;#12;#12;#12;#12;#12;#12;#12;#12;External Distribution 05/16/05 Plasma Research of Sciences, Central Research Institute for Physics, Hungary Dr. P. Kaw, Institute for Plasma Research, India Ms. P.J. Pathak, Librarian, Institute for Plasma Research, India Dr. Pandji Triadyaksa, Fakultas MIPA

Note: This page contains sample records for the topic "density laboratory plasmas" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Impact of the energy loss spatial profile and shear viscosity to entropy density ratio for the Mach cone vs. head shock signals produced by a fast moving parton in a quark-gluon plasma  

E-Print Network [OSTI]

We compute the energy and momentum deposited by a fast moving parton in a quark-gluon plasma using linear viscous hydrodynamics with an energy loss per unit length profile proportional to the path length and with different values of the shear viscosity to entropy density ratio. We show that when varying these parameters, the transverse modes still dominate over the longitudinal ones and thus energy and momentum is preferentially deposited along the head-shock, as in the case of a constant energy loss per unit length profile and the lowest value for the shear viscosity to entropy density ratio.

Alejandro Ayala; Jorge David Castano-Yepes; Isabel Dominguez; Maria Elena Tejeda-Yeomans

2014-12-18T23:59:59.000Z

262

Electromagnetic solitary pulses in a magnetized electron-positron plasma  

SciTech Connect (OSTI)

A theory for large amplitude compressional electromagnetic solitary pulses in a magnetized electron-positron (e-p) plasma is presented. The pulses, which propagate perpendicular to the external magnetic field, are associated with the compression of the plasma density and the wave magnetic field. Here the solitary wave magnetic field pressure provides the restoring force, while the inertia comes from the equal mass electrons and positrons. The solitary pulses are formed due to a balance between the compressional wave dispersion arising from the curl of the inertial forces in Faraday's law and the nonlinearities associated with the divergence of the electron and positron fluxes, the nonlinear Lorentz forces, the advection of the e-p fluids, and the nonlinear plasma current densities. The compressional solitary pulses can exist in a well-defined speed range above the Alfven speed. They can be associated with localized electromagnetic field excitations in magnetized laboratory and space plasmas composed of electrons and positrons.

Shukla, P. K. [RUB International Chair, International Centre for Advanced Studies in Physical Sciences, Fakultaet fuer Physik und Astronomie, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany); Eliasson, B. [Institut fuer Theoretische Physik, Fakultaet fuer Physik und Astronomie, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany); Stenflo, L. [Department of Physics, Linkoeping University, SE-58183 Linkoeping (Sweden)

2011-03-15T23:59:59.000Z

263

Measurements and simulations of shock wave generated plasma-vacuum interface  

SciTech Connect (OSTI)

A controlled gradient gas jet was designed, constructed, and tested at the Naval Research Laboratory for the generation of high density and sharp gradient plasma regions. The gas jet uses a laser-generated shock wave to control the density gradient at the vacuum and neutral gas interface. The length scale of the laser produced plasma density gradient is fully controlled by the strength of the shock wave and can be varied continuously from100 {mu}m for a weak shock to under 20 {mu}m in case of strong shock wave as verified by the experimental results and simulations.

Kaganovich, D.; Helle, M. H.; Gordon, D. F.; Ting, A. [Plasma Physics Division, Naval Research Laboratory, Washington, D.C. 20375 (United States)

2011-12-15T23:59:59.000Z

264

Methane Conversion by Plasma Assisted Methods  

E-Print Network [OSTI]

and Helge Egsgaard2 1Optics and Plasma Research Department 2Biosystems Department Risø National Laboratory

265

Princeton Plasma Physics Laboratory News  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas ConchasPassive Solar Home DesignPresentations Presentations926 2.804lab-leadershipiterarchive

266

Princeton Plasma Physics Laboratory News  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas ConchasPassive Solar Home DesignPresentations Presentations926

267

Princeton Plasma Physics Laboratory News  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 - SeptemberMicroneedles for4-16 FOR Primary Authorstem The

268

Princeton Plasma Physics Laboratory News  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 - SeptemberMicroneedles for4-16 FOR Primary Authorstem The

269

Princeton Plasma Physics Laboratory News  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 - SeptemberMicroneedles for4-16 FOR Primary Authorstem The

270

Princeton Plasma Physics Laboratory News  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 - SeptemberMicroneedles for4-16 FOR Primary Authorstem The

271

Princeton Plasma Physics Laboratory News  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 - SeptemberMicroneedles for4-16 FOR Primary Authorstem The

272

Princeton Plasma Physics Laboratory News  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 - SeptemberMicroneedles for4-16 FOR Primary Authorstem The

273

Princeton Plasma Physics Laboratory News  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 - SeptemberMicroneedles for4-16 FOR Primary Authorstem The

274

E-Print Network 3.0 - atmospheric plasma torch Sample Search...  

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

Collection: Chemistry 63 ASSOCIATED LABORATORY PLASMA PHYSICS AND ENGINEERING Summary: interaction problems. 3.8 Ecological Plasma Engineering Laboratory The emission to the...

275

Laboratory tests to evaluate and study formation damage with low-density drill-in fluids (LDDIF) for horizontal well completions in low pressure and depleted reservoirs  

E-Print Network [OSTI]

The increasing number of open hole horizontal well completions in low-pressure and depleted reservoirs requires the use of non-damaging low-density drill-in fluids (LDDIF) to avoid formation damage and realize optimum well productivity. To address...

Chen, Guoqiang

2002-01-01T23:59:59.000Z

276

Laboratory and Field Performance of Buried Steel-Reinforced High Density Polyethylene (SRHDPE) Pipes in a Ditch Condition under a Shallow Cover  

E-Print Network [OSTI]

the disadvantages of metal and plastic pipes, a new product, steel-reinforced high-density polyethylene (SRHDPE) pipe, has been developed and introduced to the market, which has high-strength steel reinforcing ribs wound helically and covered by corrosion...

Khatri, Deep Kumar

2014-05-31T23:59:59.000Z

277

A Langmuir Probe Diagnostic for Use in Inhomogeneous, Time-Varying Plasmas Produced by High-Energy Laser Ablation  

SciTech Connect (OSTI)

Langmuir probes (LP) are used extensively to characterize plasma environments produced by radio frequency, pulsed plasma thrusters, and laser ablation. We discuss here the development of a LP diagnostic to examine high-density, high-temperature inhomogeneous plasmas such as those that can be created at the University of Rochester's Laboratory for Laser Energetics OMEGA facility. We have configured our diagnostic to examine the velocity of the plasma expanding from the target. We observe velocities of approximately 16-17 cm/{micro}s, with individual LP currents displaying complex structures, perhaps due to the multiple atomic species and ionization states that exist.

Patterson, J R; Emig, J A; Fournier, K B; Jenkins, P P; Trautz, K M; Seiler, S W; Davis, J F

2012-05-01T23:59:59.000Z

278

Design of a free-electron laser driven by the LBNL laser-plasma-accelerator  

E-Print Network [OSTI]

plasma accelerator at the LBNL LOASIS facility”, in: Proc.electron laser driven by the LBNL laser-plasma-accelerator ?National Laboratory (LBNL) laser-plasma accelerator, whose

2008-01-01T23:59:59.000Z

279

E-Print Network 3.0 - atmospheric thermal plasmas Sample Search...  

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

particles in a plasma... D | 1 the laser senses plasma ... Source: Howard, John - Plasma Research Laboratory, Research School of Physical Sciences and Engineering, Australian...

280

Intense Magnetized Plasma-Wall Interaction  

SciTech Connect (OSTI)

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.

Bauer, Bruno S. [UNR] [UNR; Fuelling, Stephan [UNR] [UNR

2013-11-30T23:59:59.000Z

Note: This page contains sample records for the topic "density laboratory plasmas" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

E-Print Network 3.0 - alter plasma lipid Sample Search Results  

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

National Laboratory Technical University of Denmark... , Department for Optics and Plasma Research, Frederiksborgvej 399, 4000 Roskilde, ... Source: Ris National Laboratory...

282

Prepared for the U.S. Department of Energy under Contract DE-AC02-76CH03073. Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

is available for sale to the general public from: U.S. Department of Commerce National Technical Information plasma flow had ion energies of ~100 eV and electron energies of ~20 eV. The discharge was powered

283

Analysis of plasma waves observed within local plasma injections seen in Saturn's magnetosphere  

E-Print Network [OSTI]

Analysis of plasma waves observed within local plasma injections seen in Saturn's magnetosphere J; published 17 May 2008. [1] Plasma injections or density depletion regions have been reported plasma in a cooler, locally produced plasma background. The injected plasma undergoes dispersion

Gurnett, Donald A.

284

alamos national laboratory analysis: Topics by E-print Network  

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

Department Multidisciplinary Databases and Resources Websites Summary: Optics and Plasma Research Department, Ris National Laboratory Required publisher statement Copyright:...

285

argonne national laboratories: Topics by E-print Network  

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

Department Multidisciplinary Databases and Resources Websites Summary: Optics and Plasma Research Department, Ris National Laboratory Required publisher statement Copyright:...

286

alamos national laboratory: Topics by E-print Network  

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

Department Multidisciplinary Databases and Resources Websites Summary: Optics and Plasma Research Department, Ris National Laboratory Required publisher statement Copyright:...

287

argonne national laboratory: Topics by E-print Network  

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

Department Multidisciplinary Databases and Resources Websites Summary: Optics and Plasma Research Department, Ris National Laboratory Required publisher statement Copyright:...

288

INSTITUTE OF PHYSICS PUBLISHING PLASMA PHYSICS AND CONTROLLED FUSION Plasma Phys. Control. Fusion 48 (2006) 777787 doi:10.1088/0741-3335/48/6/005  

E-Print Network [OSTI]

for Thomson scattering J Howard Plasma Research Laboratory, Australian National University, Canberra, ACT 0200

Howard, John

289

ambient plasma technique: Topics by E-print Network  

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

for motional Stark effect Plasma Physics and Fusion Websites Summary: John Howard Plasma Research Laboratory, Australian National University, Canberra ACT 0200, Australia the...

290

Diagnostics of Plasma Properties in Broad Line Region of AGNs  

E-Print Network [OSTI]

The Boltzmann-plot (BPT) method for laboratory plasma diagnostic was used for a quick estimate of physical conditions in the Broad Line Region (BLR) of 14 Active Galactic Nuclei (AGNs). For the BLR of nine AGNs, where PLTE exist, the estimated electron temperature are in the range T $\\sim$ 130000K - 37000K are in good agreement with previous estimates. The estimated electron densities depend on the opacity of the emitting plasma in the BLR, and they are in range from $10^9\\rm cm^{-3}$ (for optically thick plasma) to $10^{14}\\rm cm^{-3}$ (for optically thin plasma). Although an alternative of PLTE in some AGNs may be very high intrinsic reddening effect, this method may be used for fast insight into physical processes in the BLR prior to applying more sophisticated physical models.

Luka C. Popovic

2003-09-23T23:59:59.000Z

291

Plasma technology directory  

SciTech Connect (OSTI)

The Plasma Technology Directory has two main goals: (1) promote, coordinate, and share plasma technology experience and equipment within the Department of Energy; and (2) facilitate technology transfer to the commercial sector where appropriate. Personnel are averaged first by Laboratory and next by technology area. The technology areas are accelerators, cleaning and etching deposition, diagnostics, and modeling.

Ward, P.P.; Dybwad, G.L.

1995-03-01T23:59:59.000Z

292

Laboratories are Needed to Explore, Explain VLBACHANDRA  

E-Print Network [OSTI]

Princeton Plasma Physics Laboratory Sandia National Laboratory Stone and Webster The Boeing Company stream of about 150 visitors per week log on to the FIRE web site since the site was initiated in early

293

E-Print Network 3.0 - argon plasmas measured Sample Search Results  

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

; Plasma Physics and Fusion 82 Approach for control of high-density plasma reactors through optimal pulse shaping* Summary: the accessible plasma parameter space over...

294

HEAVY ION FUSION SCIENCE VIRTUALNATIONAL LABORATORY 2nd QUARTER 2009 MILESTONE REPORT: Perform beam and target experiments with a new induction bunching module, extended FEPS plasma, and improved target diagnostic and positioning equipment on NDCX  

E-Print Network [OSTI]

FEPS plasma, and improved target diagnostic and positioningFEPS plasma, and improved target diagnostic and positioningoptical target diagnostic system, and FCAPS plasma injection

Bieniosek, F.M.

2010-01-01T23:59:59.000Z

295

Electro-optically modulated polarizing Fourier-transform spectrometer for plasma  

E-Print Network [OSTI]

-integrated emis- The author is with the Plasma Research Laboratory, Australian National University, Canberra

Howard, John

296

Prepared for the U.S. Department of Energy under Contract DE-AC02-76CH03073. Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

successfully achieved a significant reduction in recycling with large-area liquid lithium plasma to the study of the effects of a liquid lithium toroidal limiter and evaporative lithium coatings on overall as resistance to erosion, neutron activation, and radiation damage due to their constantly renewed natures

297

Prepared for the U.S. Department of Energy under Contract DE-AC02-76CH03073. Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

Physics Laboratory Investigation of HHFW and NBI Combined Heating in NSTX B.P. LeBlanc, R.E. Bell, S in Fiscal Year 2005. The home page for PPPL Reports and Publications is: http://www.ntis.gov/ordering.htm #12;Investigation of HHFW and NBI Combined Heating in NSTX* B.P. LeBlanca , R.E. Bella , S. Bernabeia

298

Prepared for the U.S. Department of Energy under Contract DE-AC02-76CH03073. Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

and a fiber optic bundle. Neutron radiation damage was a major factor in the choice of competing lens Physics Laboratory Conceptual Design Studies of the KSTAR Bay-Nm Cassette and Thomson Scattering Optics R://www.ntis.gov/ordering.htm #12;Conceptual Design Studies of the KSTAR Bay-Nm Cassette and Thomson Scattering Optics R. Feder, R

299

E-Print Network 3.0 - adiabatic time-dependent density Sample...  

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

that allows Source: Dewar, Robert L. - Department of Theoretical Physics & Plasma Research Laboratory, Australian National University Collection: Plasma Physics and Fusion...

300

Equilibria and Stability in Partially Relaxed Plasma-Vacuum Systems  

E-Print Network [OSTI]

, Canberra, ACT 0200, Australia. b Princeton Plasma Physics Laboratory P.O. Box 451, Princeton, New Jersey

Hudson, Stuart

Note: This page contains sample records for the topic "density laboratory plasmas" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Effects of Large Area Liquid Lithium Limiters on Spherical Torus Plasmas  

SciTech Connect (OSTI)

Use of a large-area liquid lithium surface as a first wall has significantly improved the plasma performance in the Current Drive Experiment-Upgrade (CDX-U) at the Princeton Plasma Physics Laboratory. Previous CDX-U experiments with a partially-covered toroidal lithium limiter tray have shown a decrease in impurities and the recycling of hydrogenic species. Improvements in loading techniques have permitted nearly full coverage of the tray surface with liquid lithium. Under these conditions, there was a large drop in the loop voltage needed to sustain the plasma current. The data are consistent with simulations that indicate more stable plasmas having broader current profiles, higher temperatures, and lowered impurities with liquid lithium walls. As further evidence for reduced recycling with a liquid lithium limiter, the gas puffing had to be increased by up to a factor of eight for the same plasma density achieved with an empty toroidal tray limiter.

R. Kaita; R. Majeski; M. Boaz; P. Efthimion; G. Gettelfinger; T. Gray; D. Hoffman; S. Jardin; H. Kugel; P. Marfuta; T. Munsat; C. Neumeyer; S. Raftopoulos; V. Soukhanovskii; J. Spaleta; G. Taylor; J. Timberlake; R. Woolley; L. Zakharov; M. Finkenthal; D. Stutman; L. Delgado-Aparicio; R.P. Seraydarian; G. Antar; R. Doerner; S. Luckhardt; M. Baldwin; R.W. Conn; R. Maingi; M. Menon; R. Causey; D. Buchenauer; M. Ulrickson; B. Jones; D. Rodgers

2004-06-07T23:59:59.000Z

302

Experimental Characterization of Plasma Heating with Beating Electrostatic Waves  

E-Print Network [OSTI]

Experimental Characterization of Plasma Heating with Beating Electrostatic Waves Benjamin Jorns and Edgar Y. Choueiri Electric Propulsion and Plasma Dynamics Laboratory, Princeton University, Princeton, NJ, 08540 The heating of ions in a magnetized plasma by two electrostatic waves whose frequencies

Choueiri, Edgar

303
304

Plasma Phys. Control. Fusion 38 (1996) 18051816. Printed in the UK A new scheme for heterodyne polarimetry with high  

E-Print Network [OSTI]

, Association Euratom-FOM, PO Box 1207, 3430 BE Nieuwegein, The Netherlands Plasma Research Laboratory

Howard, John

305

ASSESSMENTOF BURNING-PLASMA PHENOMENA COMPACTIGNITION TOKAMAK  

E-Print Network [OSTI]

#12;MFACPANEL XIV MEMBERS Dale M. Meade, Princeton Plasma Physics Laboratory (Chairman) David E. Callen, University of Wisconsin Bruno Coppi, Massachusetts Institute of Technology Harry Dreicer, Los

306

Results from Plasma Wakefield Experiments at FACET  

SciTech Connect (OSTI)

We report initial results of the Plasma Wakefield Acceleration (PWFA) Experiments performed at FACET - Facility for Advanced aCcelertor Experimental Tests at SLAC National Accelerator Laboratory. At FACET a 23 GeV electron beam with 1.8 x 10{sup 10} electrons is compressed to 20 {mu}m longitudinally and focused down to 10 {mu}m x 10 {mu}m transverse spot size for user driven experiments. Construction of the FACET facility completed in May 2011 with a first run of user assisted commissioning throughout the summer. The first PWFA experiments will use single electron bunches combined with a high density lithium plasma to produce accelerating gradients > 10 GeV/m benchmarking the FACET beam and the newly installed experimental hardware. Future plans for further study of plasma wakefield acceleration will be reviewed. The experimental hardware and operation of the plasma heat-pipe oven have been successfully commissioned. Plasma wakefield acceleration was not observed because the electron bunch density was insufficient to ionize the lithium vapor. The remaining commissioning time in summer 2011 will be dedicated to delivering the FACET design parameters for the experimental programs which will begin in early 2012. PWFA experiments require the shorter bunches and smaller transverse sizes to create the plasma and drive large amplitude wakefields. Low emittance and high energy will minimize head erosion which was found to be a limiting factor in acceleration distance and energy gain. We will run the PWFA experiments with the design single bunch conditions in early 2012. Future PWFA experiments at FACET are discussed in [5][6] and include drive and witness bunch production for high energy beam manipulation, ramped bunch to optimize tranformer ratio, field-ionized cesium plasma, preionized plasmas, positron acceleration, etc.. We will install a notch collimator for two-bunch operation as well as new beam diagnostics such as the X-band TCAV [7] to resolve the two bunches. With these new instruments and desired beam parameters in place next year, we will be able to complete the studies of plasma wakefield acceleration in the next few years.

Li, S.Z.; Clarke, C.I.; England, R.J.; Frederico, J.; Gessner, S.J.; Hogan, M.J.; Jobe, R.K.; Litos, M.D.; Walz, D.R.; /SLAC; Muggli, P.; /Munich, Max Planck Inst.; An, W.; Clayton, C.E.; Joshi, C.; Lu, W.; Marsh, K.A.; Mori, W.; Tochitsky, S.; /UCLA; Adli, E.; /U. Oslo

2011-12-13T23:59:59.000Z

307

The Heavy Ion Fusion Science Virtual National Laboratory  

E-Print Network [OSTI]

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

Gilson, Erik

308

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

E-Print Network [OSTI]

FEPS plasma and the plasma in the final focus solenoid. TheI Final Focus Solenoid (FFS) in order to generate plasma onplasma sources (CAPS) streams from left to right into the final focus

Lidia, S.

2010-01-01T23:59:59.000Z

309

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

SciTech Connect (OSTI)

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

Witherspoon, F. Douglas [HyperV Technologies Corp.; Welch, Dale R. [Voss Scientific, LLC; Thompson, John R. [FAR-TECH, Inc.; MacFarlane, Joeseph J. [Prism Computational Sciences Inc.; Phillips, Michael W. [Advanced Energy Systems, Inc.; Bruner, Nicki [Voss Scientific, LLC; Mostrom, Chris [Voss Scientific, LLC; Thoma, Carsten [Voss Scientific, LLC; Clark, R. E. [Voss Scientific, LLC; Bogatu, Nick [FAR-TECH, Inc.; Kim, Jin-Soo [FAR-TECH, Inc.; Galkin, Sergei [FAR-TECH, Inc.; Golovkin, Igor E. [Prism Computational Sciences, Inc.; Woodruff, P. R. [Prism Computational Sciences, Inc.; Wu, Linchun [HyperV Technologies Corp.; Messer, Sarah J. [HyperV Technologies Corp.

2014-05-20T23:59:59.000Z

310

Comparing the performance of plasma impedance probes and Langmuir probes for RF plasma diagnostics  

E-Print Network [OSTI]

Comparing the performance of plasma impedance probes and Langmuir probes for RF plasma diagnostics probing, a less developed technique, can possibly overcome these problems. Better plasma diagnostic tools Ethan Dale, Dr. Mitchell Walker High-Power Electric Propulsion Laboratory Objective Plasma is the most

Walker, Mitchell

311

Characterization of the conduction phase of a plasma opening switch using a hydrogen plasma  

E-Print Network [OSTI]

Characterization of the conduction phase of a plasma opening switch using a hydrogen plasma J. J Pulsed Power Physics Branch, Plasma Physics Division, Naval Research Laboratory, Washington, D.C. 20375 Y 2004; published online 7 January 2005) Plasma opening switch (POS) experiments were conducted

312

Propagation and oblique collision of ion-acoustic solitary waves in a magnetized dusty electronegative plasma  

SciTech Connect (OSTI)

The propagation and oblique collision of ion-acoustic (IA) solitary waves in a magnetized dusty electronegative plasma consisting of cold mobile positive ions, Boltzmann negative ions, Boltzmann electrons, and stationary positive/negative dust particles are studied. The extended Poincaré-Lighthill-Kuo perturbation method is employed to derive the Korteweg-de Vries equations and the corresponding expressions for the phase shifts after collision between two IA solitary waves. It turns out that the angle of collision, the temperature and density of negative ions, and the dust density of opposite polarity have reasonable effects on the phase shift. Clearly, the numerical results demonstrated that the IA solitary waves are delayed after the oblique collision. The current finding of this work is applicable in many plasma environments having negative ion species, such as D- and F-regions of the Earth's ionosphere and some laboratory plasma experiments.

El-Labany, S. K.; Behery, E. E. [Department of Physics, Faculty of Science, Damietta University, P.O. Box 34517 New Damietta (Egypt)] [Department of Physics, Faculty of Science, Damietta University, P.O. Box 34517 New Damietta (Egypt); El-Shamy, E. F. [Department of Physics, Faculty of Science, Damietta University, P.O. Box 34517 New Damietta (Egypt) [Department of Physics, Faculty of Science, Damietta University, P.O. Box 34517 New Damietta (Egypt); Department of Physics, Faculty of Science, King Khalid University, P.O. Box 9004 Abha (Saudi Arabia)

2013-12-15T23:59:59.000Z

313

Phase-mixing of Langmuir oscillations in cold electron-positron-ion plasmas  

SciTech Connect (OSTI)

Space-time evolution of Langmuir oscillations in a cold homogeneous electron-positron-ion plasma has been analyzed by employing a straightforward perturbation expansion method, showing phase-mixing and, thus, wave-breaking of excited oscillations at arbitrary amplitudes. Within an assumption of infinitely massive ions, an approximate phase-mixing time is found to scale as ?{sub pe}t{sub mix}?[(6/?{sup 2})((2??){sup 5/2}/(1??))]{sup 1/3}, where “?” and “?” (= n{sub 0i}/n{sub 0e}) are the amplitude of perturbation and the ratio of equilibrium ion density to equilibrium electron density, respectively, and ?{sub pe}??(4?n{sub 0e}e{sup 2}/m) is the electron plasma frequency. The results presented on phase-mixing of Langmuir modes in multispecies plasmas are expected to be relevant to laboratory and astrophysical environments.

Maity, Chandan [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700 064 (India)

2014-07-15T23:59:59.000Z

314

Review of controlled laboratory experiments on physics of magnetic reconnection  

E-Print Network [OSTI]

Lundquist number of S 1 10 as well as in MHD plasmas with S 100 1000. This article puts a special focus Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey Abstract. We review results-correlated plasma parameters at multiple plasma locations simultaneously, while satellites can only provide

315

Characterization of spatially resolved high resolution x-ray spectrometers for high energy density physics and light source experiments  

SciTech Connect (OSTI)

A high resolution 1D imaging x-ray spectrometer concept comprising a spherically bent crystal and a 2D pixelated detector is being optimized for diagnostics of small sources such as high energy density physics (HEDP) and synchrotron radiation or x-ray free electron laser experiments. This instrument is used on tokamak experiments for Doppler measurements of ion temperature and plasma flow velocity profiles. Laboratory measurements demonstrate a resolving power, E/?E of order 10?000 and spatial resolution better than 10 ?m. Initial tests of the high resolution instrument on HEDP plasmas are being performed.

Hill, K. W., E-mail: khill@pppl.gov; Bitter, M.; Delgado-Aparacio, L.; Efthimion, P.; Pablant, N. A. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Lu, J. [Key Laboratory of Optoelectronic Technology and System of Ministry of Education, Chongqing University, Chongqing 400030 (China); Beiersdorfer, P.; Chen, H.; Magee, E. [Physics Division, Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

2014-11-15T23:59:59.000Z

316

E-Print Network 3.0 - astrophysical plasma physics Sample Search...  

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

Science 64 Michigan Institute for Plasma Science Summary: Methods for Plasma Physics Dr. Phillip Colella Lawrence Berkeley National Laboratory Tuesday, 8... Michigan Institute for...

317

E-Print Network 3.0 - advanced vacuum plasma Sample Search Results  

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Model In ... Source: Dewar, Robert L. - Department of Theoretical Physics & Plasma Research Laboratory, Australian National University Collection: Plasma Physics and Fusion...

318

E-Print Network 3.0 - arc plasma furnace Sample Search Results  

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

PLASMA PHYSICS AND ENGINEERING Summary: replace costly traditional technologies as incineration and conventional plasma arc furnaces, and provide... ASSOCIATED LABORATORY ON...

319

Michigan Institute for Plasma Science and Engineering Fall 2011 Seminar Series  

E-Print Network [OSTI]

Michigan Institute for Plasma Science and Engineering Fall 2011 Seminar Series Date, Time EECS Dr. Joe Borovsky AOSS and Los Alamos National Laboratory The Solar Wind Plasma Wednesday

Shyy, Wei

320

Energy in density gradient  

E-Print Network [OSTI]

Inhomogeneous plasmas and fluids contain energy stored in inhomogeneity and they naturally tend to relax into lower energy states by developing instabilities or by diffusion. But the actual amount of energy in such inhomogeneities has remained unknown. In the present work the amount of energy stored in a density gradient is calculated for several specific density profiles in a cylindric configuration. This is of practical importance for drift wave instability in various plasmas, and in particular in its application in models dealing with the heating of solar corona because the instability is accompanied with stochastic heating, so the energy contained in inhomogeneity is effectively transformed into heat. It is shown that even for a rather moderate increase of the density at the axis in magnetic structures in the corona by a factor 1.5 or 3, the amount of excess energy per unit volume stored in such a density gradient becomes several orders of magnitude greater than the amount of total energy losses per unit ...

Vranjes, J

2015-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "density laboratory plasmas" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

The MaPLE device of Saha Institute of Nuclear Physics: Construction and its plasma aspects  

SciTech Connect (OSTI)

The Magnetized Plasma Linear Experimental (MaPLE) device is a low cost laboratory plasma device at Saha Institute of Nuclear Physics fabricated in-house with the primary aim of studying basic plasma physics phenomena such as plasma instabilities, wave propagation, and their nonlinear behavior in magnetized plasma regime in a controlled manner. The machine is specially designed to be a versatile laboratory device that can provide a number of magnetic and electric scenario to facilitate such studies. A total of 36 number of 20-turn magnet coils, designed such as to allow easy handling, is capable of producing a uniform, dc magnetic field of about 0.35 T inside the plasma chamber of diameter 0.30 m. Support structure of the coils is planned in an innovative way facilitating straightforward fabrication and easy positioning of the coils. Further special feature lies in the arrangement of the spacers between the coils that can be maneuvered rather easily to create different magnetic configurations. Various methods of plasma production can be suitably utilized according to the experimental needs at either end of the vacuum vessel. In the present paper, characteristics of a steady state plasma generated by electron cyclotron resonance method using 2.45 GHz microwave power are presented. Scans using simple probe drives revealed that a uniform and long plasma column having electron density {approx}3-5x10{sup 10} cm{sup -3} and temperature {approx}7-10 eV, is formed in the center of the plasma chamber which is suitable for wave launching experiments.

Pal, Rabindranath; Biswas, Subir; Basu, Subhasis; Chattopadhyay, Monobir; Basu, Debjyoti; Chaudhuri, Manis [Saha Institute of Nuclear Physics, I/AF Bidhannagar, Kolkata 700 064 (India)

2010-07-15T23:59:59.000Z

322

Dynamics and manipulation of the dominant 13.5 nm in-band extreme ultraviolet emitting region of laser-produced Sn plasmas  

E-Print Network [OSTI]

Plasma Diagnostics ..Principles of plasma diagnostics Cambridge University Press,the laser pulse. Plasma Diagnostics 2.6.1. Electron Density

Yuspeh, Samuel Edward

2011-01-01T23:59:59.000Z

323

Dust-acoustic waves in nonuniform dusty plasma in presence of polarization force  

SciTech Connect (OSTI)

The effects of the dust density nonuniformity and the polarization force on linear propagation of the dust-acoustic waves in a nonuniform dusty plasma (consisting of electrons, ions, and arbitrarily charged dust particles) have been theoretically investigated. It has been shown that the linear dispersion properties of the dust-acoustic (DA) waves have been significantly modified by the dust density nonuniformity, dust polarity, and the polarization force. It is also found here that the phase speed of the DA waves is decreased by the effects of polarization force, and that their amplitude increases with the decrease of equilibrium dust number density. The different situations, which are relevant to different space and laboratory dusty plasmas, have been briefly discussed.

Asaduzzaman, M.; Mamun, A. A.; Ashrafi, K. S. [Department of Physics, Jahangirnagar University, Savar, Dhaka-1342 (Bangladesh)

2011-11-15T23:59:59.000Z

324

applications laboratory colorado: Topics by E-print Network  

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

Plasma Physics Laboratory 13 O:CSUEHorticultureNative Plant Masters20132013 NPM Application.doc432013 Colorado State University Extension 2009 Geosciences Websites...

325

army research laboratory: Topics by E-print Network  

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

of the authors Perona, Pietro 51 Ris National Laboratory DTU Optics and Plasma Research Department Multidisciplinary Databases and Resources Websites Summary: Ris...

326

ames laboratory research: Topics by E-print Network  

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

of the authors Perona, Pietro 60 Ris National Laboratory DTU Optics and Plasma Research Department Multidisciplinary Databases and Resources Websites Summary: Ris...

327

ames laboratory research reactor: Topics by E-print Network  

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

of the authors Perona, Pietro 75 Ris National Laboratory DTU Optics and Plasma Research Department Multidisciplinary Databases and Resources Websites Summary: Ris...

328

ames laboratory researchers: Topics by E-print Network  

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

of the authors Perona, Pietro 60 Ris National Laboratory DTU Optics and Plasma Research Department Multidisciplinary Databases and Resources Websites Summary: Ris...

329

advanced research laboratory: Topics by E-print Network  

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

of the authors Perona, Pietro 89 Ris National Laboratory DTU Optics and Plasma Research Department Multidisciplinary Databases and Resources Websites Summary: Ris...

330

aging research laboratory: Topics by E-print Network  

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

of the authors Perona, Pietro 36 Ris National Laboratory DTU Optics and Plasma Research Department Multidisciplinary Databases and Resources Websites Summary: Ris...

331

atlantic research laboratory: Topics by E-print Network  

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

of the authors Perona, Pietro 62 Ris National Laboratory DTU Optics and Plasma Research Department Multidisciplinary Databases and Resources Websites Summary: Ris...

332

Formation of Imploding Plasma Liners for HEDP and MIF Application  

SciTech Connect (OSTI)

Plasma jets with high density and velocity have a number of important applications in fusion energy and elsewhere, including plasma refueling, disruption mitigation in tokamaks, magnetized target fusion, injection of momentum into centrifugally confined mirrors, plasma thrusters, and high energy density plasmas (HEDP). In Magneto-Inertial Fusion (MIF), for example, an imploding material liner is used to compress a magnetized plasma to fusion conditions and to confine the resulting burning plasma inertially to obtain the necessary energy gain. The imploding shell may be solid, liquid, gaseous, or a combination of these states. The presence of the magnetic field in the target plasma suppresses thermal transport to the plasma shell, thus lowering the imploding power needed to compress the target to fusion conditions. This allows the required imploding momentum flux to be generated electromagnetically using off-the-shelf pulsed power technology. Practical schemes for standoff delivery of the imploding momentum flux are required and are open topics for research. One approach for accomplishing this, called plasma jet driven magneto-inertial fusion (PJMIF), uses a spherical array of pulsed plasma guns to create a spherically imploding shell of very high velocity, high momentum flux plasma. This approach requires development of plasma jet accelerators capable of achieving velocities of 50-200 km/s with very precise timing and density profiles, and with high total mass and density. Low-Z plasma jets would require the higher velocities, whereas very dense high-Z plasma shells could achieve the goal at velocities of only 50-100 km/s. In this report, we describe our work to develop the pulsed plasma gun technology needed for an experimental scientific exploration of the PJMIF concept, and also for the other applications mentioned earlier. The initial goal of a few hundred of hydrogen at 200 km/s was eventually replaced with accelerating 8000 ?g of argon or xenon to 50 km/s for the Plasma Liner Experiment (PLX) at Los Alamos National Laboratory (LANL). Initial work used existing computational and analytical tools to develop and refine a specific plasma gun concept having a novel tapered coaxial electromagnetic accelerator contour with an array of symmetric ablative plasma injectors. The profile is designed to suppress the main barrier to success in coaxial guns, namely the blow-by instability in which the arc slips past and outruns the bulk of the plasma mass. Efforts to begin developing a set of annular non-ablative plasma injectors for the coaxial gun, in order to accelerate pure gases, resulted in development of linear parallel-plate MiniRailguns that turned out to work well as plasma guns in their own right and we subsequently chose them for an initial plasma liner experiment on the PLX facility at LANL. This choice was mainly driven by cost and schedule for that particular experiment, while longer term goals still projected use of coaxial guns for reactor-relevant applications for reasons of better symmetry, lower impurities, more compact plasma jet formation, and higher gun efficiency. Our efforts have focused mainly on 1) developing various plasma injection systems for both coax and linear railguns and ensuring they work reliably with the accelerator section, 2) developing a suite of plasma and gun diagnostics, 3) performing computational modeling to design and refine the plasma guns, 4) establishing a research facility dedicated to plasma gun development, and finally, 5) developing plasma guns and associated pulse power systems capable of achieving these goals and installing and testing the first two gun sets on the PLX facility at LANL. During the second funding cycle for this program, HyperV joined in a collaborative effort with LANL, the University of Alabama at Huntsville, and the University of New Mexico to perform a plasma liner experiment (PLX) to investigate the physics and technology of forming spherically imploding plasma liners. HyperV’s tasks focused on developing the plasma guns and associated pulse power syst

Witherspoon, F. Douglas [HyperV Technologies Corp.; Case, Andrew [HyperV Technologies Corp.; Brockington, Samuel [HyperV Technologies Corp.y; Messer, Sarah [HyperV Technologies Corp.; Bomgardner, Richard [HyperV Technologies Corp.; Phillips, Mike [HyperV Technologies Corp.; Wu, Linchun [HyperV Technologies Corp.; Elton, Ray [University of Maryland

2014-11-11T23:59:59.000Z

333

Plasma Phys. Control. Fusion 41 (1999) 271284. Printed in the UK PII: S0741-3335(99)88859-9 Optical coherence-based techniques for motional Stark effect  

E-Print Network [OSTI]

John Howard Plasma Research Laboratory, Australian National University, Canberra ACT 0200, Australia

Howard, John

334

Reprint from "PLASMA PHYSICS  

E-Print Network [OSTI]

ATOMIC ENERGY AGENCY VIENNA, 1983 Link: http://charles.karney.info/biblio/white83.html #12;CONFINEMENTIN. ALBERT, C.F.F. KARNEY Plasma Physics Laboratory, Princeton University, Princeton, New Jersey, United motion. Of course a stochastic field has no such coordinates, but the systems of interest for confinement

Karney, Charles

335

INSTITUTE OF PHYSICS PUBLISHING PLASMA PHYSICS AND CONTROLLED FUSION Plasma Phys. Control. Fusion 47 (2005) 919940 doi:10.1088/0741-3335/47/6/012  

E-Print Network [OSTI]

-Planck-Institut f¨ur Plasmaphysik, Greifswald, 17491, Germany 2 Plasma Research Laboratory, Australian National

Howard, John

336

Plasmas are Hot and Fusion is Cool  

SciTech Connect (OSTI)

Plasmas are Hot and Fusion is Cold. The DOE Princeton Plasma Physics Laboratory (PPPL) collaborates to develop fusion as a safe, clean and abundant energy source for the future. This video discusses PPPL's research and development on plasma, the fourth state of matter.

None

2011-01-01T23:59:59.000Z

337

THE SOLAR WIND PLASMA Dr. Joe Borovsky  

E-Print Network [OSTI]

involved multidipole plasma devices. Current research interests focus on structure in the solar wind THE SOLAR WIND PLASMA Dr. Joe Borovsky Los Alamos National Laboratory and University, magnetized, collisionless plasma, important for the geomagnetic activity that it drives at Earth and for its

Shyy, Wei

338

Fully nonlinear solitary waves in a dusty electronegative multispecies plasmas  

SciTech Connect (OSTI)

The formation and dynamics of fully nonlinear ion-acoustic solitary waves, which accompany electronegative plasmas composed of positive ions, two-negative ions, isothermal electrons, as well as a fraction of stationary charged (positive or negative) dust impurities are investigated. By using the hydrodynamic and Poisson equations, an energy-integral equation involving a Sagdeev pseudo-potential is derived. Using the latter, we have defined precisely the existence regions of the electrostatic localized pulses. The critical total negative ions concentration {alpha}{sub c} and critical second-negative ion density ratio {nu}{sub c} thresholds, which indicate where the solitary pulses set in, have been determined for various regimes. Numerical calculations reveal that only supersonic pulses can exist. The total negative ions concentration, the second-to-total negative ions density ratio, electrons-to-positive ions temperature ratio, dust impurities concentration, positive-to-negative mass ratio, and Mach number have been investigated on the nonlinear wave profile. It is found that the total negative ion concentration as well as the dust particles concentration play the significant role in deciding the polarity of the propagating pulses. The results could be applied to investigate and predict the behavior of the nonlinear solitary structure in future laboratory plasma experiment having dusty electronegative multispecies plasmas as referred by Ichiki et al.[Phys. Plasmas 8, 4275 (2001)].

El-Labany, S. K. [Department of Physics, Faculty of Science-Damietta, Mansoura University, New Damietta City 34517 (Egypt); Moslem, W. M. [Department of Physics, Faculty of Science, Port Said University, Port Said (Egypt); International Centre for Advanced Studies in Physical Sciences, Faculty of Physics and Astronomy, Ruhr University Bochum, D-44780 Bochum (Germany); Shnishin, Kh. A.; El-Tantawy, S. A. [Department of Physics, Faculty of Science, Port Said University, Port Said (Egypt); Shukla, P. K. [RUB International Chair, International Centre for Advanced Studies in Physical Sciences, Faculty of Physics and Astronomy, Ruhr University Bochum, D-44780 Bochum (Germany); Institut fuer Theoretische Physik, Fakultaet fuer Physik und Astronomie, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany)

2011-04-15T23:59:59.000Z

339

E-Print Network 3.0 - atmospheric plasma enhanced Sample Search...  

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

A.H. Nielsen, Association... EURATOM -- Ris National Laboratory Optics and Plasma Research Department, OPL-128 DK-4000 Roskilde Source: Ris National Laboratory...

340

Plasma Materials Interaction Issues For Burning Plasma Experiments  

E-Print Network [OSTI]

­ Resistance to neutron damage #12;MAU 5 11/15/2001 The FIRE Burning Plasma Device · A compact high field surface sees high density and temperature plasma · Key issues are hydrogen trapping, erosion, and thermal trapping and release, surface segregation · Materials science for nuclear radiation damage, thermal fatigue

Note: This page contains sample records for the topic "density laboratory plasmas" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

DENSITY LIMITS IN TOROIDAL PLASMAS MARTIN GREENWALD  

E-Print Network [OSTI]

;ACKNOWLEDGEMENTS · All people who have worked in this area over the years · Note particularly people who power scaling) (Axon 1980) #12;SCALING REFINED BY INCLUSION OF DATA FROM SHAPED TOKAMAKS · Greenwald

Greenwald, Martin

342

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinanInformation Desert Southwest Region service area.

343

Exploring Astrophysical Phenomena in the Laboratory with Lasers  

E-Print Network [OSTI]

for frontier science Matter at high pressure, density Crab Nebula SNR 1987A NGC 4261 HH-47 jet Jupiter) plasmas Pressure 1 Mbar or energy density > 1011 J/m3 #12;Generating an HED plasma with scale sizes, densities, and velocities #12;Extreme conditions generated by ICF implosions are comparable to conditions

344

A Schamel equation for ion acoustic waves in superthermal plasmas  

SciTech Connect (OSTI)

An investigation of the propagation of ion acoustic waves in nonthermal plasmas in the presence of trapped electrons has been undertaken. This has been motivated by space and laboratory plasma observations of plasmas containing energetic particles, resulting in long-tailed distributions, in combination with trapped particles, whereby some of the plasma particles are confined to a finite region of phase space. An unmagnetized collisionless electron-ion plasma is considered, featuring a non-Maxwellian-trapped electron distribution, which is modelled by a kappa distribution function combined with a Schamel distribution. The effect of particle trapping has been considered, resulting in an expression for the electron density. Reductive perturbation theory has been used to construct a KdV-like Schamel equation, and examine its behaviour. The relevant configurational parameters in our study include the superthermality index ? and the characteristic trapping parameter ?. A pulse-shaped family of solutions is proposed, also depending on the weak soliton speed increment u{sub 0}. The main modification due to an increase in particle trapping is an increase in the amplitude of solitary waves, yet leaving their spatial width practically unaffected. With enhanced superthermality, there is a decrease in both amplitude and width of solitary waves, for any given values of the trapping parameter and of the incremental soliton speed. Only positive polarity excitations were observed in our parametric investigation.

Williams, G., E-mail: gwilliams06@qub.ac.uk; Kourakis, I. [Centre for Plasma Physics, Department of Physics and Astronomy, Queen's University Belfast, BT7 1NN, Northern Ireland (United Kingdom); Verheest, F. [Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan 281, B-9000 Gent (Belgium); School of Chemistry and Physics, University of KwaZulu-Natal, Durban 4000 (South Africa); Hellberg, M. A. [School of Chemistry and Physics, University of KwaZulu-Natal, Durban 4000 (South Africa); Anowar, M. G. M. [Department of Physics, Begum Rokeya University, Rangpur, Rangpur-5400 (Bangladesh)

2014-09-15T23:59:59.000Z

345

Three-dimensional stability of dust-ion acoustic solitary waves in a magnetized multicomponent dusty plasma with negative ions  

SciTech Connect (OSTI)

Using the small-k expansion perturbation method, the three-dimensional stability of dust-ion acoustic solitary waves (DIASWs) in a magnetized multicomponent dusty plasma containing negative heavy ions and stationary variable-charge dust particles is analyzed. A nonlinear Zakharov-Kuznetsov equation adequate for describing these solitary structures is derived. Moreover, the basic features of the DIASWs are studied. The determination of the stability region leads to two different cases depending on the oblique propagation angle. In addition, the growth rate of the produced waves is estimated. The increase of either the negative ion number density or their temperatures or even the number density of the dust grains results in reducing the wave growth rate. Finally, the present results should elucidate the properties of DIASWs in a multicomponent plasma with negative ions, particularly in laboratory experiment and plasma process.

El-Taibany, W. F.; El-Shamy, E. F. [Department of Physics, Faculty of Science, Mansoura University, Damietta Branch, P.O. 34517, Damietta El-Gedida (Egypt); El-Bedwehy, N. A. [Department of Mathematics, Faculty of Science, Mansoura University, Damietta Branch, P.O. 34517, Damietta El-Gedida (Egypt)

2011-03-15T23:59:59.000Z

346

Laboratory experiments on arc deflection and instability  

SciTech Connect (OSTI)

This article describes experiments on arc deflection instability carried out during the past few years at the Princeton University Plasma Physics Laboratory (PPPL). The approach has been that of plasma physicists interested in arcs, but they believe these results may be useful to engineers who are responsible for controlling arc behavior in large electric steel furnaces.

Zweben, S.; Karasik, M.

2000-03-21T23:59:59.000Z

347

Design of a high particle flux hydrogen helicon plasma source for used in plasma materials interaction studies  

SciTech Connect (OSTI)

Existing linear plasma materials interaction (PMI) facilities all use plasma sources with internal electrodes. An rf-based helicon source is of interest because high plasma densities can be generated with no internal electrodes, allowing true steady state operation with minimal impurity generation. Work has begun at Oak Ridge National Laboratory (ORNL) to develop a large (15 cm) diameter helicon source producing hydrogen plasmas with parameters suitable for use in a linear PMI device: n(e) >= 10(19)m(-3), T(e) = 4-10 eV, particle flux Gamma(p) > 10(23) m(-3) s(-1), and magnetic field strength |B| up to I T in the source region. The device, whose design is based on a previous hydrogen helicon source operated at ORNL[1], will operate at rf frequencies in the range 10 - 26 MHz, and power levels up to similar to 100 kW. Limitations in cooling will prevent operation for pulses longer than several seconds, but a major goal will be the measurement of power deposition on device structures so that a later steady state version can be designed. The device design, the diagnostics to be used, and results of rf modeling of the device will be discussed. These include calculations of plasma loading, resulting currents and voltages in antenna structures and the matching network, power deposition profiles, and the effect of high |B| operation on power absorption.

Goulding, Richard Howell [ORNL; Chen, Guangye [ORNL; Meitner, Steven J [ORNL; Baity Jr, F Wallace [ORNL; Caughman, John B [ORNL; Owen, Larry W [ORNL

2009-01-01T23:59:59.000Z

348

Design of a high particle flux hydrogen helicon plasma source for used in plasma materials interaction studies  

SciTech Connect (OSTI)

Existing linear plasma materials interaction (PMI) facilities all use plasma sources with internal electrodes. An rf-based helicon source is of interest because high plasma densities can be generated with no internal electrodes, allowing true steady state operation with minimal impurity generation. Work has begun at Oak Ridge National Laboratory (ORNL) to develop a large (15 cm) diameter helicon source producing hydrogen plasmas with parameters suitable for use in a linear PMI device: n{sub e}{>=}10{sup 19} m{sup -3}, T{sub e} = 4-10 eV, particle flux {gamma}{sub p}>10{sup 23}m{sup -3} s{sup -1}, and magnetic field strength |B| up to 1 T in the source region. The device, whose design is based on a previous hydrogen helicon source operated at ORNL[1], will operate at rf frequencies in the range 10-26 MHz, and power levels up to {approx}100 kW. Limitations in cooling will prevent operation for pulses longer than several seconds, but a major goal will be the measurement of power deposition on device structures so that a later steady state version can be designed. The device design, the diagnostics to be used, and results of rf modeling of the device will be discussed. These include calculations of plasma loading, resulting currents and voltages in antenna structures and the matching network, power deposition profiles, and the effect of high |B| operation on power absorption.

Goulding, R. H.; Chen, G.; Meitner, S.; Baity, F. W.; Caughman, J. B. O.; Owen, L. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831-6169 (United States)

2009-11-26T23:59:59.000Z

349

E-Print Network 3.0 - arc plasma deposition Sample Search Results  

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

Notes Summary: Introduction to Plasma Physics C17 Lecture Notes John Howard Plasma Research Laboratory Research... 12;2 12;Contents 1 BASIC PLASMA PHENOMENA 7 1.1 What is...

350

Three-dimensional structure of magnetic reconnection in a laboratory C. D. Cothran, M. Landreman, and M. R. Brown  

E-Print Network [OSTI]

) laboratory plasma at the Swarthmore Spheromak Experiment. An array of 600 magnetic probes which resolve ion of partial spheromak merging events. Counter-helicityspheromaksmergerapidly,andreconnection activity clearly Electromagnetics: Optics; KEYWORDS: magneticreconnection,magnetohydrodynamics,plasma,laboratory, spheromak, ssx

Brown, Michael R.

351

Meter scale plasma source for plasma wakefield experiments  

SciTech Connect (OSTI)

High accelerating gradients generated by a high density electron beam moving through plasma has been used to double the energy of the SLAC electron beam [1]. During that experiment, the electron current density was high enough to generate its own plasma without significant head erosion. In the newly commissioned FACET facility at SLAC, the peak current will be lower and without pre-ionization, head erosion will be a significant challenge for the planned experiments. In this work we report on our design of a meter scale plasma source for these experiments to effectively avoid the problem of head erosion. The plasma source is based on a homogeneous metal vapor gas column that is generated in a heat pipe oven [2]. A lithium oven over 30 cm long at densities over 10{sup 17} cm{sup -3} has been constructed and tested at UCLA. The plasma is then generated by coupling a 10 TW short pulse Ti:Sapphire laser into the gas column using an axicon lens setup. The Bessel profile of the axicon setup creates a region of high intensity that can stretch over the full length of the gas column with approximately constant diameter. In this region of high intensity, the alkali metal vapor is ionized through multi-photon ionization process. In this manner, a fully ionized meter scale plasma of uniform density can be formed. Methods for controlling the plasma diameter and length will also be discussed.

Vafaei-Najafabadi, N.; Shaw, J. L.; Marsh, K. A.; Joshi, C.; Hogan, M. J. [Department of Electrical Engineering, University of California Los Angeles, Los Angeles, CA 90095 (United States); SLAC National Accelerator Laboratory, Menlo Park, CA 94025 (United States)

2012-12-21T23:59:59.000Z

352

Sandia National Laboratories: Geomechanics Laboratory  

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

Science: Latest News and Events Earth Science: Facilities and Equipment Bureau of Land Management Fossil Energy Liquid Natural Gas (LNG) Clean Coal Geomechanics Laboratory User...

353

Effects of neutral interactions on velocity-shear-driven plasma waves  

SciTech Connect (OSTI)

In a laboratory experiment, we demonstrate the substantial effects that collisions between charged and neutral particles have on low-frequency (?{sub i}????????{sub e}) shear-driven electrostatic lower hybrid waves in a plasma. We establish a strong (up to 2.5?kV/m) highly localized electric field with a length scale shorter than the ion gyroradius, so that the ions in the plasma, unlike the electrons, do not develop the full E?×?B drift velocity. The resulting shear in the particle velocities initiates the electron-ion hybrid (EIH) instability, and we observe the formation of strong waves in the vicinity of the shear with variations in plasma densities of 10% or greater. Our experimental configuration allows us to vary the neutral background density by more than a factor of two while holding the charged particle density effectively constant. Not surprisingly, increasing the neutral density decreases the growth rate/saturation amplitude of the waves and increases the threshold electric field necessary for wave formation, but the presence of neutrals affects the dominant wave frequency as well. We show that a 50% increase in the neutral density decreases the wave frequency by 20% while also suppressing the electric field dependence of the frequency that is observed when fewer neutrals are present. The majority of these effects, as well as the values of the frequencies we observe, closely match the predictions of previously developed linear EIH instability theory, for which we present the results of a numerical solution.

Enloe, C. L. [Physics Department, US Air Force Academy, Colorado Springs, Colorado 80840 (United States); Tejero, E. M.; Amatucci, W. E.; Crabtree, C.; Ganguli, G. [Plasma Physics Division, Naval Research Laboratory, Washington, DC 20375 (United States); Sotnikov, V. [Sensors Directorate, Air Force Research Laboratory, Dayton, Ohio 45433 (United States)

2014-06-15T23:59:59.000Z

354

Neutral depletion and the helicon density limit  

SciTech Connect (OSTI)

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.

Magee, R. M.; Galante, M. E.; Carr, J. Jr.; Lusk, G.; McCarren, D. W.; Scime, E. E. [West Virginia University, Morgantown, West Virginia 26506 (United States)] [West Virginia University, Morgantown, West Virginia 26506 (United States)

2013-12-15T23:59:59.000Z

355

Princeton Plasma Physics Laboratory NSTX Experimental Proposal  

E-Print Network [OSTI]

Chit Review Board (designated by Run Coordinator) MINOR MODIFICATIONS (Approved by Experimental helical field, resonant electromagnetic coupling of rational surfaces to error fields or the conducting global nature of toroidal rotation damping at N / Nno-wall > 1 2) The observed dependence of rotation

Princeton Plasma Physics Laboratory

356

Princeton Plasma Physics Laboratory NSTX Experimental Proposal  

E-Print Network [OSTI]

Responsible Division: Experimental Research Operations Chit Review Board (designated by Run Coordinator) MINOR redistribution and loss of fast ions resulting from the bursts. In addition, eternal braking fields eigenfunctions. Comparison with calculated BAAE eigenfunctions will improve understanding of the exact nature

Princeton Plasma Physics Laboratory

357

Princeton Plasma Physics Laboratory NSTX Machine Proposal  

E-Print Network [OSTI]

-XMP-62 2 / 5 REVIEWERS (designated by RLM) Organization/Position Name Signature ATI Test Director designated by RLM NSTX Work Permit T-MOD (OP-AD-03) Independent Review ES&H Review MINOR MODIFICATIONS #12;OP Independent Reviewer NB RF Diagnostics TRAINING (designated by RLM) Training required: No Yes Instructor

Princeton Plasma Physics Laboratory

358

Princeton Plasma Physics Laboratory NSTX Machine Proposal  

E-Print Network [OSTI]

-XMP-58 2 / 5 REVIEWERS (designated by RLM) Organization/Position Name Signature ATI Test Director designated by RLM NSTX Work Permit T-MOD (OP-AD-03) Independent Review ES&H Review MINOR MODIFICATIONS #12;OP Independent Reviewer NB RF Diagnostics TRAINING (designated by RLM) Training required: No Yes Instructor

Princeton Plasma Physics Laboratory

359

Princeton Plasma Physics Laboratory NSTX Machine Proposal  

E-Print Network [OSTI]

MINOR MODIFICATIONS #12;OP-XMP-60 2 / 6 REVIEWERS (designated by RLM) Organization/Position Name Procedure Requirements designated by RLM NSTX Work Permit T-MOD (OP-AD-03) Independent Review ES&H Review Signature ATI D. Mueller Test Director D. Gates Independent Reviewer NB M. Cropper RF Diagnostics TRAINING

Princeton Plasma Physics Laboratory

360

Princeton Plasma Physics Laboratory NSTX Machine Proposal  

E-Print Network [OSTI]

designated by RLM MINOR MODIFICATIONS #12;OP-XMP-59 2 / 6 REVIEWERS (designated by RLM) Organization/Position Name Signature ATI D. Mueller Test Director M. Podestà Independent Reviewer NB M. Cropper RF Diagnostics TRAINING (designated by RLM) Training required: No Yes Instructor

Princeton Plasma Physics Laboratory

Note: This page contains sample records for the topic "density laboratory plasmas" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Princeton Plasma Physics Laboratory NSTX Experimental Proposal  

E-Print Network [OSTI]

at Constant q OP-XP-617 1. Overview of planned experiment Goal: Measure RF power loss properties as a function of magnetic field constant q to elucidate: · RF power loss scaling with B under similar stability conditions of shots around 112699) [J. Hosea et al., 2005 RF Conference]. Thus the RF power loss is significantly

Princeton Plasma Physics Laboratory

362

Princeton Univer sity Plasma Physics Laboratory  

E-Print Network [OSTI]

tion, use, and disposal in whole or in part by or for the United States government is permitted-half of the earth's present popula tion, we should require about one Q per year. Our past history of consumption has an annual growth rate of electrical power production of greater than 6% has been experienced in recent years

363

Princeton Plasma Physics Laboratory NSTX Experimental Proposal  

E-Print Network [OSTI]

Division: Experimental Research Operations Chit Review Board (designated by Run Coordinator) MINOR others, that affects the divertor detachment threshold. Deuterium will be injected from the outer wall divertor is cold (Te

Princeton Plasma Physics Laboratory

364

H IGHLIGHTS PRINCETON PLASMA PHYSICS LABORATORY  

E-Print Network [OSTI]

low­cost fuel. . No chemical combustion products and therefore no contribution to acid rain or global

365

PROCEDURE COVER SHEET Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

Quality Assurance/Quality Control AC Power Maintenance and Operations Division Energy Conversion Systems Engineering Environmental Restoration & Waste Management Division Water Systems Neutral Beam (Heating Systems Branch of Electrical Engineering) Radiofrequency (Heating Systems Branch of Electrical Engineering

Princeton Plasma Physics Laboratory

366

Turbulence in Astrophysical and Laboratory Plasmas  

E-Print Network [OSTI]

MIPSE, Univ of Michigan September 15, 2010 #12;Contributing Colleagues Steve Cowley (UKAEA & Imperial-principles modeling · Identification of Alfvenic solar wind turbulence · Conclusion #12;Kinetic theory when (or ) f

Shyy, Wei

367

Sandia National Laboratories: fundamental 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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1development Sandia,evaluatingfull module characterization HelioVoltphysics of

368

Sandia National Laboratories: light-emitting 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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1developmentturbine blade manufacturinglife-cycle analysis

369

Sandia National Laboratories: plasma materials interactions studies  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1developmentturbine bladelifetime ismobileparallelplantplasma materials interactions

370

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas ConchasPassiveSubmitted forHighlights Nuclear Physics (NP) NP HomeHasan ResearchPhysics

371

PROCEDURE COVER SHEET Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

Restoration & Waste Management Division Water Systems R. Herskowitz Neutral Beam T. Stevenson, M. Cropper Computer Tritium Quality Assurance/Quality Control AC Power/MG M. Awad Maintenance and Operations Division Energy Conversion Systems G. Baker, S. Ramakrishnan, J. Corl Engineering S. Raftopoulos Environmental

Princeton Plasma Physics Laboratory

372

PROCEDURE COVER SHEET Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

Assurance/Quality Control AC Power Maintenance and Operations Division Energy Conversion Systems E. Baker, M. Awad Engineering E. Perry Environmental Restoration & Waste Management Division Water Systems M. Kalish-Site Shift Supervisor W. Blanchard, R. Camp NSTX D-Site Caretaking Vacuum J. Winston Computer Tritium Quality

Princeton Plasma Physics Laboratory

373

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

SciTech Connect (OSTI)

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.

Schroeder, Carl; Esarey, Eric; Benedetti, Carlo; Leemans, Wim

2013-08-06T23:59:59.000Z

374

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

SciTech Connect (OSTI)

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.

Schroeder, C. B.; Esarey, E.; Benedetti, C.; Leemans, W. P. [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)] [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

2013-08-15T23:59:59.000Z

375

Plasma Turbulence Simulations Reveal Promising Insight for Fusion...  

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

Physics Laboratory (PPPL), a DOE collaborative national center for fusion and plasma research in New Jersey, are running large-scale simulations at the Argonne Leadership...

376

area plasma source: Topics by E-print Network  

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

Department of Nuclear Engineering, 1406 W. Green St., Urbana, IL 61801, USA 2 Plasma Research Laboratory-mode) to helicon (W-mode) transitions in research reactors having...

377

MICROSYSTEMS LABORATORIES  

E-Print Network [OSTI]

15 nm MICROSYSTEMS TECHNOLOGY LABORATORIES ANNUAL RESEARCH REPORT 2014 MASSACHUSETTS INSTITUTE OF TECHNOLOGY CAMBRIDGE, MA AUGUST 2014 #12;MTL Annual Research Report 2014 Director Jesús A. del Alamo Project........................................................................ 47 Energy: Photovoltaics, Energy Harvesting, Batteries, Fuel Cells

Culpepper, Martin L.

378

Plasma generating apparatus for large area plasma processing  

DOE Patents [OSTI]

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.

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

1991-07-16T23:59:59.000Z

379

Plasma generating apparatus for large area plasma processing  

DOE Patents [OSTI]

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.

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

1991-01-01T23:59:59.000Z

380

Head-on collision of ion-acoustic solitary waves in multicomponent plasmas with positrons  

SciTech Connect (OSTI)

The head-on collision between two ion-acoustic solitary waves in an unmagnetized multicomponent plasma consisting of hot ions, hot positrons, and two-electron temperature distributions is investigated using the extended Poincare-Lighthill-Kuo method. The Kortwege-de Vries equations and the analytical phase shifts after the head-on collision of two solitary waves in this multicomponent plasma are obtained. The effects of two different types of isothermal electrons, the ratio of the hot ion temperature to the effective temperature, the ratio of the effective temperature to the positron temperature, the ratio of the number density of positrons to that of electrons species, and the physical processes (either isothermal or adiabatic) on the phase shifts are studied. It is found that these parameters can significantly influence the phase shifts of the solitons. The relevance of this investigation to space and laboratory plasmas is pointed out.

El-Shamy, E. F.; Sabry, R. [Department of Physics, Theoretical Physics Group, Faculty of Science, Mansoura University, Damietta-Branch, New Damietta 34517, Damietta (Egypt); Moslem, W. M. [Department of Physics, Faculty of Science, Port Said University, Port Said (Egypt); Shukla, P. K. [Institut fuer Theoretische Physik IV, Fakultaet fuer Physik und Astronomie, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany)

2010-08-15T23:59:59.000Z

Note: This page contains sample records for the topic "density laboratory plasmas" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Presented at UFA Burning Plasma Science Workshop II  

E-Print Network [OSTI]

Idaho National Engineering Laboratory Lawrence Livermore National Laboratory Massachusetts Institute, Madison, WI · Charge for First and Second meetings Scientific value of a Burning Plasma experiment Scientific readiness to proceed with such an experiment Is the FIRE mission scientifically appropriate

382

Non-linear Plasma Wake Growth of Electron Holes  

E-Print Network [OSTI]

An object's wake in a plasma with small Debye length that drifts \\emph{across} the magnetic field is subject to electrostatic electron instabilities. Such situations include, for example, the moon in the solar wind wake and probes in magnetized laboratory plasmas. The instability drive mechanism can equivalently be considered drift down the potential-energy gradient or drift up the density-gradient. The gradients arise because the plasma wake has a region of depressed density and electrostatic potential into which ions are attracted along the field. The non-linear consequences of the instability are analysed in this paper. At physical ratios of electron to ion mass, neither linear nor quasilinear treatment can explain the observation of large-amplitude perturbations that disrupt the ion streams well before they become ion-ion unstable. We show here, however, that electron holes, once formed, continue to grow, driven by the drift mechanism, and if they remain in the wake may reach a maximum non-linearly stable...

Hutchinson, I H; Zhou, C

2015-01-01T23:59:59.000Z

383

Diagnostic technique for measuring plasma parameters near surfaces in radio frequency discharges  

E-Print Network [OSTI]

Diagnostic technique for measuring plasma parameters near surfaces in radio frequency discharges September 1998 A plasma diagnostic technique for measuring the electron density, electron temperature the plasma parameters. The technique is demonstrated by implementing the diagnostic in a computer model

Kushner, Mark

384

Fluorination mechanisms of Al{sub 2}O{sub 3} and Y{sub 2}O{sub 3} surfaces irradiated by high-density CF{sub 4}/O{sub 2} and SF{sub 6}/O{sub 2} plasmas  

SciTech Connect (OSTI)

Fluorination of Al{sub 2}O{sub 3} and Y{sub 2}O{sub 3} surfaces was investigated by irradiating high-density, helicon-wave CF{sub 4}/O{sub 2} and SF{sub 6}/O{sub 2} plasmas. The Al{sub 2}O{sub 3} surface bombarded by high-flux positive ions of the CF{sub 4}/O{sub 2} plasma was fluorinated significantly. On contrast, Y{sub 2}O{sub 3} was less fluorinated than Al{sub 2}O{sub 3} when they were irradiated by the same CF{sub 4}/O{sub 2} plasma. The analysis of the Al{sub 2}O{sub 3} surface irradiated by the CF{sub 4}/O{sub 2} plasma suggests that the fluorination is triggered by reactions between fluorocarbon deposit and Al-O bonding with the assistance of ion bombardment. On the other hand, irradiation of the SF{sub 6}/O{sub 2} plasma induced less significant fluorination on the Al{sub 2}O{sub 3} surface. This suggests a lower reaction probability between sulfur fluoride deposit and Al-O bonding. The difference in the fluorination of the Al{sub 2}O{sub 3} and Y{sub 2}O{sub 3} surfaces induced by the irradiations of the CF{sub 4}/O{sub 2} and SF{sub 6}/O{sub 2} plasmas is understood by comparing the bonding energies of C-O, S-O, Al-O, and Y-O.

Miwa, Kazuhiro; Takada, Noriharu; Sasaki, Koichi [Department of Electrical Engineering and Computer Science, Nagoya University, Nagoya, 464-8603 (Japan); Plasma Nanotechnology Research Center, Nagoya University, Nagoya 464-8603 (Japan)

2009-07-15T23:59:59.000Z

385

Aerodynamic Focusing Of High-Density Aerosols  

SciTech Connect (OSTI)

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.

Ruiz, D. E.; Fisch, Nathaniel

2014-02-24T23:59:59.000Z

386

Absolute x-ray yields from laser-irradiated germanium-doped low-density aerogels  

SciTech Connect (OSTI)

The x-ray yields from laser-irradiated germanium-doped ultra-low-density aerogel plasmas have been measured in the energy range from sub-keV to {approx_equal}15 keV at the OMEGA laser facility at the Laboratory for Laser Energetics, University of Rochester. The targets' x-ray yields have been studied for variation in target size, aerogel density, laser pulse length, and laser intensity. For targets that result in plasmas with electron densities in the range of {approx_equal}10% of the critical density for 3{omega} light, one can expect 10-11 J/sr of x rays with energies above 9 keV, and 600-800 J/sr for energies below 3.5 keV. In addition to the x-ray spectral yields, the x-ray temporal waveforms have been measured and it is observed that the emitted x rays generally follow the delivered laser power, with late-time enhancements of emitted x-ray power correlated with hydrodynamic compression of the hot plasma. Further, the laser energy reflected from the target by plasma instabilities is found to be 2%-7% of the incident energy for individual beam intensities {approx_equal}10{sup 14}-10{sup 15} W/cm{sup 2}. The propagation of the laser heating in the target volume has been characterized with two-dimensional imaging. Source-region heating is seen to be correlated with the temporal profile of the emitted x-ray power.

Fournier, K. B.; Satcher, J. H.; May, M. J.; Poco, J. F.; Sorce, C. M.; Colvin, J. D.; Hansen, S. B.; MacLaren, S. A.; Moon, S. J.; Davis, J. F. [Lawrence Livermore National Laboratory, Livermore, California 94551 (United States); Girard, F.; Villette, B.; Primout, M.; Babonneau, D. [Commissariat a l'Energie Atomique-Direction des Application Militaires (CEA/DAM), Ile-de-France, F91297 Arpajon (France); Coverdale, C. A.; Beutler, D. E. [Sandia National Laboratory, Albuquerque, New Mexico 87185 (United States)

2009-05-15T23:59:59.000Z

387

Absolute X-Ray Yields From Laser-Irradiated Ge-Doped Low-Density Aerogels  

SciTech Connect (OSTI)

We have used the OMEGA laser (Laboratory for Laser Energetics, University of Rochester) to measure the X-ray yields from laser-irradiated germanium-doped ultra-low-density aerogel plasmas in the energy range from sub-keV to {approx} 15 keV. They have studied the targets X-ray yields with variation in target size, aerogel density, laser pulse length and laser intensity. For targets that result in plasmas with electron densities in the range of {approx} 10% of the critical density for 3{omega} light, one can expect 10-11 J/sr of X-rays with energies above 9 keV, and 600-800 J/sr for energies below 3.5 keV. In addition to the X-ray spectral yields, they have measured the X-ray temporal waveforms and found that the emitted X rays generally follow the delivered laser power, with late-time enhancements of emitted X-ray power correlated with hydrodynamic compression of the hot plasma. Also, they find the laser energy reflected from the target by plasma instabilities to be 2-7% of the incident energy for individual beam intensities {approx} 10{sup 14}-10{sup 15} W/cm{sup 2}. They also have characterized the propagation of the laser heating in the target volume with two-dimensional imaging. They find the source-region heating to be correlated with the temporal profile of the emitted X-ray power.

Fournier, K B; Satcher, J H; May, M J; Poco, J F; Sorce, C M; Colvin, J D; Hansen, S B; MacLaren, S A; Moon, S J; Davis, J F; Girard, F; Villette, B; Primout, M; Babonneau, D; Coverdale, C A; Beutler, D E

2009-02-10T23:59:59.000Z

388

Roles of polarization force and nonthermal electron on dust-acoustic waves in an inhomogeneous dusty plasma with positively charged dust  

SciTech Connect (OSTI)

The influence of polarization force (PF) (arises due to dust density inhomogeneity), nonthermal electrons, and dust density inhomogeneity associated with positively charged dust on linear dust-acoustic (DA) waves in an inhomogeneous unmagnetized dusty plasma are investigated. By taking the normal mode analysis, the dispersion relation in such a non-Maxwellian inhomogeneous plasma is obtained, and that the dispersion properties of the DA waves are significantly modified by the presence of PF and nonthermal electrons. The PF is increased with the increase of nonthermal electrons. It is found that the phase speed of the DA waves is significantly decreased with the presence of PF and nonthermal electrons. The potential associated with the DA waves is de-enhanced with the increase of equilibrium dust number density. The role of positive dust number density on dispersion properties is also shown. The present findings relevant to different scenarios in laboratory and space dusty plasma, such as Martian ionosphere, solar flares, TEXTOR-94 tokamak plasmas, rf excited argon magnetoplasma, etc., can be useful to understand the properties of localized electrostatic disturbances in those dusty plasma system, are also briefly addressed.

Asaduzzaman, M.; Mamun, A. A. [Department of Physics, Jahangirnagar University, Savar, Dhaka 1342 (Bangladesh)

2012-09-15T23:59:59.000Z

389

ALPS - advanced limiter-divertor plasma-facing systems.  

SciTech Connect (OSTI)

The Advanced Limiter-divertor Plasma-facing Systems (ALPS) program was initiated in order to evaluate the potential for improved performance and lifetime for plasma-facing systems. The main goal of the program is to demonstrate the advantages of advanced limiter/divertor systems over conventional systems in terms of power density capability, component lifetime, and power conversion efficiency, while providing for safe operation and minimizing impurity concerns for the plasma. Most of the work to date has been applied to free surface liquids. A multi-disciplinary team from several institutions has been organized to address the key issues associated with these systems. The main performance goals for advanced limiters and diverters are a peak heat flux of >50 MW/m{sup 2},elimination of a lifetime limit for erosion, and the ability to extract useful heat at high power conversion efficiency ({approximately}40%). The evaluation of various options is being conducted through a combination of laboratory experiments, modeling of key processes, and conceptual design studies. The current emphasis for the work is on the effects of free surface liquids on plasma edge performance.

Allain, J. P.; Bastasz, R.; Brooks, J. N.; Evans, T.; Hassanein, A.; Luckhardt, S.; Maingi, R.; Mattas, R. F.; McCarthy, K.; Mioduszewski, P.; Mogahed, E.; Moir, R.; Molokov, S.; Morely, N.; Nygren, R.; Reed, C.; Rognlien, T.; Ruzic, D.; Sviatoslavsky, I.; Sze, D.; Tillack, M.; Ulrickson, M.; Wade, P. M.; Wong, C.; Wooley, R.

1999-09-15T23:59:59.000Z

390

Characterization of jovian plasma embedded dust particles  

E-Print Network [OSTI]

As the data from space missions and laboratories improve, a research domain combining plasmas and charged dust is gaining in prominence. Our solar system provides many natural laboratories such as planetary rings, comet comae and tails, ejecta clouds around moons and asteroids, and Earth's noctilucent clouds for which to closely study plasma-embedded cosmic dust. One natural laboratory to study electromagnetically-controlled cosmic dust has been provided by the Jovian dust streams and the data from the instruments which were on board the Galileo spacecraft. Given the prodigious quantity of dust poured into the Jovian magnetosphere by Io and its volcanoes resulting in the dust streams, the possibility of dusty plasma conditions exist. This paper characterizes the main parameters for those interested in studying dust embedded in a plasma with a focus on the Jupiter environment. I show how to distinguish between dust-in-plasma and dusty-plasma and how the Havnes parameter P can be used to support or negate the possibility of collective behavior of the dusty plasma. The result of applying these tools to the Jovian dust streams reveals mostly dust-in-plasma behavior. In the orbits displaying the highest dust stream fluxes, portions of orbits E4, G7, G8, C21 satisfy the minimum requirements for a dusty plasma. However, the P parameter demonstrates that these mild dusty plasma conditions do not lead to collective behavior of the dust stream particles.

Amara L. Graps

2006-09-12T23:59:59.000Z

391

Positron plasma diagnostics and temperature control for antihydrogen production  

E-Print Network [OSTI]

Production of antihydrogen atoms by mixing antiprotons with a cold, confined, positron plasma depends critically on parameters such as the plasma density and temperature. We discuss non-destructive measurements, based on a novel, real-time analysis of excited, low-order plasma modes, that provide comprehensive characterization of the positron plasma in the ATHENA antihydrogen apparatus. The plasma length, radius, density, and total particle number are obtained. Measurement and control of plasma temperature variations, and the application to antihydrogen production experiments are discussed.

ATHENA Collaboration; M. Amoretti; C. Amsler; G. Bonomi; A. Bouchta; P. D. Bowe; C. Carraro; C. L. Cesar; M. Charlton; M. Doser; V. Filippini; A. Fontana; M. C. Fujiwara; R. Funakoshi; P. Genova; J. S. Hangst; R. S. Hayano; L. V. Jorgensen; V. Lagomarsino; R. Landua; D. Lindelof; E. Lodi Rizzini; M. Macri'; N. Madsen; G. Manuzio; P. Montagna; H. Pruys; C. Regenfus; A. Rotondi; G. Testera; A. Variola; D. P. van der Werf

2003-07-30T23:59:59.000Z

392

SULI at Ames Laboratory  

SciTech Connect (OSTI)

A video snapshot of the Science Undergraduate Laboratory Internship (SULI) program at Ames Laboratory.

None

2011-01-01T23:59:59.000Z

393

Publisher's Note: ''The MaPLE device of Saha Institute of Nuclear Physics: Construction and its plasma aspects'' [Rev. Sci. Instrum. 81, 073507 (2010)  

SciTech Connect (OSTI)

The Magnetized Plasma Linear Experimental (MaPLE) device is a low cost laboratory plasma device at Saha Institute of Nuclear Physics fabricated in-house with the primary aim of studying basic plasma physics phenomena such as plasma instabilities, wave propagation, and their nonlinear behavior in magnetized plasma regime in a controlled manner. The machine is specially designed to be a versatile laboratory device that can provide a number of magnetic and electric scenario to facilitate such studies. A total of 36 number of 20-turn magnet coils, designed such as to allow easy handling, is capable of producing a uniform, dc magnetic field of about 0.35 T inside the plasma chamber of diameter 0.30 m. Support structure of the coils is planned in an innovative way facilitating straightforward fabrication and easy positioning of the coils. Further special feature lies in the arrangement of the spacers between the coils that can be maneuvered rather easily to create different magnetic configurations. Various methods of plasma production can be suitably utilized according to the experimental needs at either end of the vacuum vessel. In the present paper, characteristics of a steady state plasma generated by electron cyclotron resonance method using 2.45 GHz microwave power are presented. Scans using simple probe drives revealed that a uniform and long plasma column having electron density {approx} 3-5 Multiplication-Sign 1010 cm-3 and temperature {approx} 7-10 eV, is formed in the center of the plasma chamber which is suitable for wave launching experiments.

Pal, Rabindranath; Biswas, Subir; Basu, Subhasis; Chattopadhyay, Monobir; Basu, Debjyoti; Chaudhuri, Manis [Saha Institute of Nuclear Physics, I/AF Bidhannagar, Kolkata 700 064 (India)

2010-07-15T23:59:59.000Z

394

Laboratory Directed  

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

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395

Laboratory Directors  

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

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396

Magneto-inertial Fusion: An Emerging Concept for Inertial Fusion and Dense Plasmas in Ultrahigh Magnetic Fields  

SciTech Connect (OSTI)

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.

Thio, Francis Y.C.

2008-01-01T23:59:59.000Z

397

Experiment for Plasma Energization with Beating Electrostatic Waves  

E-Print Network [OSTI]

Experiment for Plasma Energization with Beating Electrostatic Waves IEPC-2009-199 Presented September 20­24, 2009 Benjamin Jorns and Edgar Y. Choueiri Electric Propulsion and Plasma Dynamics Laboratory, Princeton University, Princeton, NJ, 08540 An experimental study of plasma heating by means

Choueiri, Edgar

398

An Optical Streak Diagnostic for Observing Anode-Cathode Plasmas for Radiographic Source Development  

SciTech Connect (OSTI)

National Security Technologies, LLC, and Sandia National Laboratories are collaborating in the development of pulsed power–driven flash x-ray radiographic sources that utilize high-intensity electron beam diodes. The RITS 6 (Radiographic Integrated Test Stand) accelerator at Sandia is used to drive a self magnetic pinch diode to produce a Bremsstrahlung x-ray source. The high electric fields and current densities associated with these short A-K gap pinch beam diodes present many challenges in diode development. Plasmas generated at both the anode and cathode affect the diode performance, which is manifested in varying spot (source) sizes, total dose output, and impedance profiles. Understanding the nature of these plasmas including closure rates and densities is important in modeling their behavior and providing insight into their mitigation. In this paper we describe a streak camera–based optical diagnostic that is capable of observing and measuring plasma evolution within the A-K gap. By imaging a region of interest onto the input slit of a streak camera, we are able to produce a time-resolved one-dimensional image of the evolving plasma. Typical data are presented.

Droemer, Darryl W. [National Security Technologies, LLC; Crain, Marlon D.; Lare, Gregory A. [National Security Technologies, LLC; Bennett, Nichelle L. [National Security Technologies, LLC; Johnston, Mark D. [Sandia National Laboratories

2013-06-13T23:59:59.000Z

399

Experimental evidence for collisional shock formation via two obliquely merging supersonic plasma jets  

SciTech Connect (OSTI)

We report spatially resolved measurements of the oblique merging of two supersonic laboratory plasma jets. The jets are formed and launched by pulsed-power-driven railguns using injected argon, and have electron density ?10{sup 14}?cm{sup ?3}, electron temperature ?1.4?eV, ionization fraction near unity, and velocity ?40?km/s just prior to merging. The jet merging produces a few-cm-thick stagnation layer, as observed in both fast-framing camera images and multi-chord interferometer data, consistent with collisional shock formation [E. C. Merritt et al., Phys. Rev. Lett. 111, 085003 (2013)].

Merritt, Elizabeth C., E-mail: emerritt@lanl.gov; Adams, Colin S. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States) [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); University of New Mexico, Albuquerque, New Mexico 87131 (United States); Moser, Auna L.; Hsu, Scott C., E-mail: scotthsu@lanl.gov; Dunn, John P.; Miguel Holgado, A. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)] [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Gilmore, Mark A. [University of New Mexico, Albuquerque, New Mexico 87131 (United States)] [University of New Mexico, Albuquerque, New Mexico 87131 (United States)

2014-05-15T23:59:59.000Z

400

Boundary Plasma Turbulence Simulations for Tokamaks  

SciTech Connect (OSTI)

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.

Xu, X; Umansky, M; Dudson, B; Snyder, P

2008-05-15T23:59:59.000Z

Note: This page contains sample records for the topic "density laboratory plasmas" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

E-Print Network 3.0 - abacc laboratories quality Sample Search...  

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

Birgitte Thestrup and Peter E. Andersen Ris National Laboratory Optics and Plasma Research... power and high efficiency. Their use is however limited by the poor beam...

402

E-Print Network 3.0 - automated laboratory laser Sample Search...  

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

Birgitte Thestrup and Peter E. Andersen Ris National Laboratory Optics and Plasma Research... .andersen@risoe.dk Broad area laser diodes and diode laser bars are attractive...

403

Characterization of BCl3/N-2 plasmas  

E-Print Network [OSTI]

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 ...

Sia, S. F.

2003-08-15T23:59:59.000Z

404

Laboratory Operations  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces and Interfaces Sample6, 2011 CERN 73-11 Laboratory I | Nuclear

405

Plasma response to electron energy filter in large volume plasma device  

SciTech Connect (OSTI)

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.

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)

2013-12-15T23:59:59.000Z

406

Atmospheric Pressure Plasma Process And Applications  

SciTech Connect (OSTI)

This paper provides a general discussion of atmospheric-pressure plasma generation, processes, and applications. There are two distinct categories of atmospheric-pressure plasmas: thermal and nonthermal. Thermal atmospheric-pressure plasmas include those produced in high intensity arcs, plasma torches, or in high intensity, high frequency discharges. Although nonthermal plasmas are at room temperatures, they are extremely effective in producing activated species, e.g., free radicals and excited state atoms. Thus, both thermal and nonthermal atmosphericpressure plasmas are finding applications in a wide variety of industrial processes, e.g. waste destruction, material recovery, extractive metallurgy, powder synthesis, and energy conversion. A brief discussion of recent plasma technology research and development activities at the Idaho National Laboratory is included.

Peter C. Kong; Myrtle

2006-09-01T23:59:59.000Z

407

Plasma Diagnostics and Plasma-Surface Interactions in Inductively Coupled Plasmas  

E-Print Network [OSTI]

Plasma Diagnostics and Plasma-Surface Interactions inLieberman Spring 2010 Plasma Diagnostics and Plasma-SurfaceJoy Titus Abstract Plasma Diagnostics and Plasma-Surface

Titus, Monica Joy

2010-01-01T23:59:59.000Z

408

Formation of imploding plasma liners for fundamental HEDP studies and MIF Standoff Driver Concept  

SciTech Connect (OSTI)

The disciplines of High Energy Density Physics (HEDP) and Inertial Confinement Fusion (ICF) are characterized by hypervelocity implosions and strong shocks. The Plasma Liner Experiment (PLX) is focused on reaching HEDP and/or ICF relevant regimes in excess of 1 Mbar peak pressure by the merging and implosion of discrete plasma jets, as a potentially efficient path towards these extreme conditions in a laboratory. In this work we have presented the first 3D simulations of plasma liner, formation, and implosion by the merging of discrete plasma jets in which ionization, thermal conduction, and radiation are all included in the physics model. The study was conducted by utilizing a smoothed particle hydrodynamics code (SPHC) and was a part of the plasma liner experiment (PLX). The salient physics processes of liner formation and implosion are studied, namely vacuum propagation of plasma jets, merging of the jets (liner forming), implosion (liner collapsing), stagnation (peak pressure), and expansion (rarefaction wave disassembling the target). Radiative transport was found to significantly reduce the temperature of the liner during implosion, thus reducing the thermal leaving more pronounced gradients in the plasma liner during the implosion compared with ideal hydrodynamic simulations. These pronounced gradients lead to a greater sensitivity of initial jet geometry and symmetry on peak pressures obtained. Accounting for ionization and transport, many cases gave higher peak pressures than the ideal hydrodynamic simulations. Scaling laws were developed accordingly, creating a non-dimensional parameter space in which performance of an imploding plasma jet liner can be estimated. It is shown that HEDP regimes could be reached with ~ 5 MJ of liner energy, which would translate to roughly 10 to 20 MJ of stored (capacitor) energy. This is a potentially significant improvement over the currently available means via ICF of achieving HEDP and nuclear fusion relevant parameters.

Cassibry, Jason [Univ. of AL in Huntsville; Hatcher, Richard [Univ. of AL in Huntsville; Stanic, Milos [Univ. of AL in Huntsville

2013-08-17T23:59:59.000Z

409

National Laboratory Impact Initiative  

Broader source: Energy.gov [DOE]

The National Laboratory Impact Initiative supports the relationship between the Office of Energy Efficiency & Renewable Energy and the national laboratory enterprise.  The national laboratories...

410

Tribology Laboratory | Argonne National Laboratory  

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

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411

Laboratory Events | Brookhaven National Laboratory  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-SeriesFlickrinformationPostdocs space controlAppraisalLaboratoryGet the tools you

412

Geoscience Laboratory | Sample Preparation Laboratories  

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413

Los Alamos National Laboratory employees, Lab contractor pledge...  

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

to plasma physics and new materials. Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and...

414

Waves generated in the plasma plume of helicon magnetic nozzle  

SciTech Connect (OSTI)

Experimental measurements have shown that the plasma plume created in a helicon plasma device contains a conical structure in the plasma density and a U-shaped double layer (US-DL) tightly confined near the throat where plasma begins to expand from the source. Recently reported two-dimensional particle-in-cell simulations verified these density and US-DL features of the plasma plume. Simulations also showed that the plasma in the plume develops non-thermal feature consisting of radial ion beams with large densities near the conical surface of the density structure. The plasma waves that are generated by the radial ion beams affecting the structure of the plasma plume are studied here. We find that most intense waves persist in the high-density regions of the conical density structure, where the transversely accelerated ions in the radial electric fields in the plume are reflected setting up counter-streaming. The waves generated are primarily ion Bernstein modes. The nonlinear evolution of the waves leads to magnetic field-aligned striations in the fields and the plasma near the conical surface of the density structure.

Singh, Nagendra; Rao, Sathyanarayan; Ranganath, Praveen [Department of Electrical and Computer Engineering, University of Alabama, Huntsville, Alabama 35899 (United States)

2013-03-15T23:59:59.000Z

415

Laser beat wave excitation of terahertz radiation in a plasma slab  

SciTech Connect (OSTI)

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.

Chauhan, Santosh; Parashar, Jetendra, E-mail: j.p.parashar@gmail.com [Department of Applied Physics, Samrat Ashok Technological Institute, Vidisha 464001, Madhya Pradesh (India)

2014-10-15T23:59:59.000Z

416

Measurement of MTF Target Plasma Temperature Using Filtered Silicon Photodiodes  

E-Print Network [OSTI]

Measurement of MTF Target Plasma Temperature Using Filtered Silicon Photodiodes Presented at the 40 Plasma Temperature Using Filtered Silicon Photodiodes Magnetized Target Fusion (MTF) is an approach photodiodes, and a plasma-density interferometer. The data obtained from the array of seven filtered silicon

417

E-Print Network 3.0 - absorbing column densities Sample Search...  

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

John - National Radio Astronomy Observatory Collection: Physics 3 Characteristics and energy balance of a plasma column sustained by a surface wave Summary: density distribution...

418

Environmental | The Ames Laboratory  

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

Environmental Management Program at the Ames Laboratory includes Waste Management, Pollution Prevention, Recycling, Cultural Resources, and the Laboratory's Environmental...

419

Dielectric covered hairpin probe for its application in reactive plasmas  

SciTech Connect (OSTI)

The hairpin probe is a well known technique for measuring local electron density in low temperature plasmas. In reactive plasmas, the probe characteristics are affected by surface sputtering, contamination, and secondary electron emission. At higher densities, the plasma absorbs the entire electromagnetic energy of hairpin and hence limits the density measurements. These issues can be resolved by covering the hairpin surface with a thin layer of dielectric. In this letter, the dielectric contribution to the probe characteristics is incorporated in a theory which is experimentally verified. The dielectric covering improves the performance of probe and also allows the hairpin tip to survive in reactive plasma where classical electrical probes are easily damaged.

Gogna, G. S.; Gaman, C.; Turner, M. M. [NCPST, School of Physical Sciences, Dublin City University, Dublin 9 (Ireland); Karkari, S. K. [Institute for Plasma Research Center, Bhat Gandhinagar, Gujarat 382428 (India)

2012-07-23T23:59:59.000Z

420

'Plasma Camp': A Different Approach to Professional Development for Physics Teachers Nicholas R. Guilbert  

E-Print Network [OSTI]

'Plasma Camp': A Different Approach to Professional Development for Physics Teachers Nicholas R-Zwicker Princeton Plasma Physics Laboratory, Box 451, Princeton, NJ 08543 azwicker@pppl.gov #12;'Plasma Camp': A Different Approach to Professional Development for Physics Teachers ABSTRACT The Plasma Physics and Fusion

Note: This page contains sample records for the topic "density laboratory plasmas" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

'Plasma Camp': A Different Approach to Professional Development for Physics Teachers Nicholas R. Guilbert  

E-Print Network [OSTI]

'Plasma Camp': A Different Approach to Professional Development for Physics Teachers Nicholas R­Zwicker Princeton Plasma Physics Laboratory, Box 451, Princeton, NJ 08543 azwicker@pppl.gov #12; 'Plasma Camp': A Different Approach to Professional Development for Physics Teachers ABSTRACT The Plasma Physics and Fusion

422

PISCES Program: Plasma-materials interactions and edge-plasma physics research  

SciTech Connect (OSTI)

This program investigates and characterizes the behavior of materials under plasma bombordment, in divertor regions. The PISCES facility is used to study divertor and plasma edge management concepts (in particular gas target divertors), as well as edge plasma turbulence and transport. The plasma source consists of a hot LaB[sub 6] cathode with an annular, water-cooled anode and attached drift tube. This cross sectional area of the plasma can be adjusted between 3 and 10 cm. A fast scanning diagnostic probe system was used for mapping plasma density profiles during biased limiter and divertor simulation experiments. Some experimental data are given on: (1) materials and surface physics, (2) edge plasma physics, and (3) a theoretical analysis of edge plasma modelling.

Conn, R.W.; Hirooka, Y.

1992-07-01T23:59:59.000Z

423

Annual Report Alfvn Laboratory  

E-Print Network [OSTI]

heating and anomalous diffusion of electrons 54 A.2.4 Complex plasmas 55 A.2.4.1 Dusty plasma research

Haviland, David

424

Plasma properties downstream of a low-power Hall thruster  

SciTech Connect (OSTI)

Triple Langmuir probes and emissive probes were used to measure the electron number density, electron temperature, and plasma potential downstream of a low-power Hall thruster. The results show a polytropic relation between electron temperature and electron number density throughout the sampled region. Over a large fraction of the plume, the plasma potential obeys the predictions of ambipolar expansion. Near the thruster centerline, however, observations show larger gradients of plasma potential than can be accounted for by this means. Radial profiles of plasma potential in the very-near-field plume are shown to contain large gradients that correspond in location to the boundaries of a visually intense plasma region.

Beal, Brian E.; Gallimore, Alec D.; Hargus, William A. Jr. [Plasmadynamics and Electric Propulsion Laboratory, Department of Aerospace Engineering, University of Michigan, College of Engineering, Ann Arbor, Michigan 48109 (United States); Air Force Research Laboratories, Edwards Air Force Base, Edwards, California 93524 (United States)

2005-12-15T23:59:59.000Z

425

INSTITUTE OF PHYSICS PUBLISHING PLASMA PHYSICS AND CONTROLLED FUSION Plasma Phys. Control. Fusion 46 (2004) 471487 PII: S0741-3335(04)69034-8  

E-Print Network [OSTI]

INSTITUTE OF PHYSICS PUBLISHING PLASMA PHYSICS AND CONTROLLED FUSION Plasma Phys. Control. Fusion the cold plasma dispersion relation, the ion­ion hybrid cutoff frequency is uniquely determined and tritium density equilibrium (nD nT), maximizing fusion reactions in a burning plasma experiment. A number

Heidbrink, William W.

426

Multi-scale investigation of sheared flows in magnetized plasmas  

SciTech Connect (OSTI)

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.

Thomas, Jr., Dr. Edward

2014-09-19T23:59:59.000Z

427

Temporal and Spatial Turbulent Spectra of MHD Plasma and an Observation of Variance Anisotropy  

E-Print Network [OSTI]

The nature of MHD turbulence is analyzed through both temporal and spatial magnetic fluctuation spectra. A magnetically turbulent plasma is produced in the MHD wind-tunnel configuration of the Swarthmore Spheromak Experiment (SSX). The power of magnetic fluctuations is projected into directions perpendicular and parallel to a local mean field; the ratio of these quantities shows the presence of variance anisotropy which varies as a function of frequency. Comparison amongst magnetic, velocity, and density spectra are also made, demonstrating that the energy of the turbulence observed is primarily seeded by magnetic fields created during plasma production. Direct spatial spectra are constructed using multi-channel diagnostics and are used to compare to frequency spectra converted to spatial scales using the Taylor Hypothesis. Evidence for the observation of dissipation due to ion inertial length scale physics is also discussed as well as the role laboratory experiment can play in understanding turbulence typica...

Schaffner, D A; Lukin, V S

2014-01-01T23:59:59.000Z

428

Empirical aspects of a Mini-Helicon Plasma Thruster Experiment (mHTX@MIT)  

E-Print Network [OSTI]

A helicon plasma source experiment has been developed and then constructed in the MIT Space Propulsion Laboratory (SPL) vacuum chamber. This experiment allows study of the intrinsic advantages of efficient helicon plasma ...

Palaia, Joseph Eugene, 1979-

2006-01-01T23:59:59.000Z

429

The Fluid Nature of Quark-Gluon Plasma  

E-Print Network [OSTI]

Collisions of heavy nuclei at very high energies offer the exciting possibility of experimentally exploring the phase transformation from hadronic to partonic degrees of freedom which is predicted to occur at several times normal nuclear density and/or for temperatures in excess of $\\sim 170$ MeV. Such a state, often referred to as a quark-gluon plasma, is thought to have been the dominant form of matter in the universe in the first few microseconds after the Big Bang. Data from the first five years of heavy ion collisions of Brookhaven National Laboratory's Relativistic Heavy Ion Collider (RHIC) clearly demonstrate that these very high temperatures and densities have been achieved. While there are strong suggestions of the role of quark degrees of freedom in determining the final-state distributions of the produced matter, there is also compelling evidence that the matter does {\\em not} behave as a quasi-ideal state of free quarks and gluons. Rather, its behavior is that of a dense fluid with very low kinematic viscosity exhibiting strong hydrodynamic flow and nearly complete absorption of high momentum probes. The current status of the RHIC experimental studies is presented, with a special emphasis on the fluid properties of the created matter, which may in fact be the most perfect fluid ever studied in the laboratory.

W. A. Zajc

2008-02-25T23:59:59.000Z

430

Method of accelerating photons by a relativistic plasma wave  

DOE Patents [OSTI]

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.

Dawson, John M. (Pacific Palisades, CA); Wilks, Scott C. (Santa Monica, CA)

1990-01-01T23:59:59.000Z

431

Effect of plasma inhomogeneity on plasma wakefield acceleration driven by long bunches  

SciTech Connect (OSTI)

Effects of plasma inhomogeneity on self-modulating proton bunches and accelerated electrons were studied numerically. The main effect is the change of the wakefield wavelength which results in phase shifts and loss of accelerated particles. This effect imposes severe constraints on density uniformity in plasma wakefield accelerators driven by long particle bunches. The transverse two stream instability that transforms the long bunch into a train of micro-bunches is less sensitive to density inhomogeneity than are the accelerated particles. The bunch freely passes through increased density regions and interacts with reduced density regions.

Lotov, K. V. [Budker Institute of Nuclear Physics SB RAS, 630090 Novosibirsk, Russia and Novosibirsk State University, 630090 Novosibirsk (Russian Federation); Pukhov, A. [Institut fuer Theoretische Physik I, Heinrich-Heine-Universitaet Duesseldorf, 40225 Duesseldorf (Germany); Caldwell, A. [Max-Planck-Institut fuer Physik, 80805 Muenchen (Germany)

2013-01-15T23:59:59.000Z

432

Nonlocal fluxes at a plasma sheath  

SciTech Connect (OSTI)

The particle and energy fluxes of electrons at the boundary of a plasma in contact with a perfectly absorbing plate are considered. In general, the fluxes are shown not to be determined by the plasma temperature and density at the plate but rather by a convolution of the plasma profiles in the vicinity of the plate. A simple empirical expression is proposed for the nonlocal fluxes, which approximately reproduces the results of a full kinetic calculation. The implications of this, to divertor plasmas near the neutralizer plate, are discussed.

Marchand, R.; Abou-Assaleh, Z.; Matte, J.P. (INRS-Energie, C. P. 1020, Varennes, Quebec, J3X 1S2, Canada (CA))

1990-06-01T23:59:59.000Z

433

NSTX Plasma Response to Lithium Coated Divertor  

SciTech Connect (OSTI)

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.

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

2011-01-21T23:59:59.000Z

434

Solitary and shock waves in magnetized electron-positron plasma  

SciTech Connect (OSTI)

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.

Lu, Ding; Li, Zi-Liang; Abdukerim, Nuriman; Xie, Bai-Song, E-mail: bsxie@bnu.edu.cn [Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, and College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China)] [Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, and College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China)

2014-02-15T23:59:59.000Z

435

E-Print Network 3.0 - ambipolar plasma flow Sample Search Results  

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

will await consideration of individual charged particle Source: Howard, John - Plasma Research Laboratory, Research School of Physical Sciences and Engineering, Australian...

436

E-Print Network 3.0 - approximation plasma polarization Sample...  

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

detectors... ) are superimposed and launched into the ... Source: Howard, John - Plasma Research Laboratory, Research School of Physical Sciences and Engineering, Australian...

437

E-Print Network 3.0 - altered plasma fatty Sample Search Results  

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

National Laboratory Technical University of Denmark... , Department for Optics and Plasma Research, Frederiksborgvej 399, 4000 Roskilde, Denmark Inactivation methods... and low...

438

E-Print Network 3.0 - ae2 plasma membrane Sample Search Results  

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

National Laboratory Technical University of Denmark... , Department for Optics and Plasma Research, Frederiksborgvej 399, 4000 Roskilde, Denmark Inactivation methods... and low...

439

arc-discharge plasma source: Topics by E-print Network  

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

Department of Nuclear Engineering, 1406 W. Green St., Urbana, IL 61801, USA 2 Plasma Research Laboratory-mode) to helicon (W-mode) transitions in research reactors having...

440

Runaway electrons in a fully and partially ionized nonideal plasma  

SciTech Connect (OSTI)

This paper reports on a study of electron runaway for a nonideal plasma in an external electric field. Based on pseudopotential models of nonideal fully and partially ionized plasmas, the friction force was derived as a function of electron velocities. Dependences of the electron free path on plasma density and nonideality parameters were obtained. The impact of the relative number of runaway electrons on their velocity and temperature was considered for classical and semiclassical models of a nonideal plasma. It has been shown that for the defined intervals of the coupled plasma parameter, the difference between the relative numbers of runaway electron values is essential for various plasma models.

Ramazanov, T.S.; Turekhanova, K.M. [Al Farabi Kazakh National University, IETP, Tole bi 96a, Almaty 050012 (Kazakhstan)

2005-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "density laboratory plasmas" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Multi-GeV Energy Gain in a Plasma-Wakefield Accelerator M. J. Hogan,1  

E-Print Network [OSTI]

m at the entrance of a 10 cm long column of lithium vapor with density 2:8 1017 atoms=cm3. The electron bunch fully ionizes the lithium vapor to create a plasma and then expels the plasma electrons-plasma interactions have demonstrated focusing gradients of MT=m [1] while laser plasma interactions have demonstrated

Jalali. Bahram

442

Progress on Plasma Lens Experiment at the Final Focus Test Beam *  

E-Print Network [OSTI]

Progress on Plasma Lens Experiment at the Final Focus Test Beam * S. Chattopadhyay 1 , P. Chen 2 Collaboration proposed and has been approved to perform the Plasma Lens Experiment at the Final Focus Test Beam of the experiment are to study plasma focusing of high energy, high density particle beams; to investigate plasma

443

Effect of argon addition on plasma parameters and dust charging in hydrogen plasma  

SciTech Connect (OSTI)

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.

Kakati, B., E-mail: bharatkakati15@gmail.com; Kausik, S. S.; Saikia, B. K. [Centre of Plasma Physics-Institute for Plasma Research, Nazirakhat, Sonapur, Kamrup 782402, Assam (India); Bandyopadhyay, M.; Saxena, Y. C. [Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India)

2014-10-28T23:59:59.000Z

444

Particle transport in plasma reactors  

SciTech Connect (OSTI)

SEMATECH and the Department of Energy have established a Contamination Free Manufacturing Research Center (CFMRC) located at Sandia National Laboratories. One of the programs underway at the CFMRC is directed towards defect reduction in semiconductor process reactors by the application of computational modeling. The goal is to use fluid, thermal, plasma, and particle transport models to identify process conditions and tool designs that reduce the deposition rate of particles on wafers. The program is directed toward defect reduction in specific manufacturing tools, although some model development is undertaken when needed. The need to produce quantifiable improvements in tool defect performance requires the close cooperation among Sandia, universities, SEMATECH, SEMATECH member companies, and equipment manufacturers. Currently, both plasma (e.g., etch, PECVD) and nonplasma tools (e.g., LPCVD, rinse tanks) are being worked on under this program. In this paper the authors summarize their recent efforts to reduce particle deposition on wafers during plasma-based semiconductor manufacturing.

Rader, D.J.; Geller, A.S.; Choi, Seung J. [Sandia National Labs., Albuquerque, NM (United States); Kushner, M.J. [Illinois Univ., Urbana, IL (United States)

1995-01-01T23:59:59.000Z

445

A restoration model of distorted electron density in wave-cutoff probe measurement  

SciTech Connect (OSTI)

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.

Jun, Hyun-Su, E-mail: mtsconst@kaist.ac.kr; Lee, Yun-Seong [Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 305-701 (Korea, Republic of)] [Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 305-701 (Korea, Republic of)

2014-02-15T23:59:59.000Z

446

Fusion Plasma Theory project summaries  

SciTech Connect (OSTI)

This Project Summary book is a published compilation consisting of short descriptions of each project supported by the Fusion Plasma Theory and Computing Group of the Advanced Physics and Technology Division of the Department of Energy, Office of Fusion Energy. The summaries contained in this volume were written by the individual contractors with minimal editing by the Office of Fusion Energy. Previous summaries were published in February of 1982 and December of 1987. The Plasma Theory program is responsible for the development of concepts and models that describe and predict the behavior of a magnetically confined plasma. Emphasis is given to the modelling and understanding of the processes controlling transport of energy and particles in a toroidal plasma and supporting the design of the International Thermonuclear Experimental Reactor (ITER). A tokamak transport initiative was begun in 1989 to improve understanding of how energy and particles are lost from the plasma by mechanisms that transport them across field lines. The Plasma Theory program has actively-participated in this initiative. Recently, increased attention has been given to issues of importance to the proposed Tokamak Physics Experiment (TPX). Particular attention has been paid to containment and thermalization of fast alpha particles produced in a burning fusion plasma as well as control of sawteeth, current drive, impurity control, and design of improved auxiliary heating. In addition, general models of plasma behavior are developed from physics features common to different confinement geometries. This work uses both analytical and numerical techniques. The Fusion Theory program supports research projects at US government laboratories, universities and industrial contractors. Its support of theoretical work at universities contributes to the office of Fusion Energy mission of training scientific manpower for the US Fusion Energy Program.

Not Available

1993-10-01T23:59:59.000Z

447

Plasma ignition and steady state simulations of the Linac4 H$^{-}$ ion source  

E-Print Network [OSTI]

The RF heating of the plasma in the Linac4 H- ion source has been simulated using an Particle-in-Cell Monte Carlo Collision method (PIC-MCC). This model is applied to investigate the plasma formation starting from an initial low electron density of 1012 m-3 and its stabilization at 1018 m-3. The plasma discharge at low electron density is driven by the capacitive coupling with the electric field generated by the antenna, and as the electron density increases the capacitive electric field is shielded by the plasma and induction drives the plasma heating process. Plasma properties such as e-/ion densities and energies, sheath formation and shielding effect are presented and provide insight to the plasma properties of the hydrogen plasma.

Mattei, S; Yasumoto, M; Hatayama, A; Lettry, J; Grudiev, A

2013-01-01T23:59:59.000Z

448

Electron velocity distribution instability in magnetized plasma wakes and artificial electron mass  

E-Print Network [OSTI]

The wake behind a large object (such as the moon) moving rapidly through a plasma (such as the solar wind) contains a region of depleted density, into which the plasma expands along the magnetic field, transverse to the ...

Hutchinson, Ian H.

449

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

E-Print Network [OSTI]

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 ...

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

2006-01-01T23:59:59.000Z

450

Mechanism behind self-sustained oscillations in direct current glow discharges and dusty plasmas  

SciTech Connect (OSTI)

An alternative explanation to the mechanism behind self-sustained oscillations of ions in direct current (DC) glow discharges is provided. Such description is distinguished from the one provided by the fluid models, where oscillations are attributed to the positive feedback mechanism associated with photoionization of particles and photoemission of electrons from the cathode. Here, oscillations arise as consequence of interaction between an ion and the surface charges induced by it at the bounding electrodes. Such mechanism provides an elegant explanation to why self-sustained oscillations occur only in the negative resistance region of the voltage-current characteristic curve in the DC glow discharges. Furthermore, this alternative description provides an elegant explanation to the formation of plasma fireballs in the laboratory plasma. It has been found that oscillation frequencies increase with ion's surface charge density, but at the rate which is significantly slower than it does with the electric field. The presented mechanism also describes self-sustained oscillations of ions in dusty plasmas, which demonstrates that self-sustained oscillations in dusty plasmas and DC glow discharges involve common physical processes.

Cho, Sung Nae [Devices R and D Center, Samsung Advanced Institute of Technology, Samsung Electronics Co., Ltd., Mt. 14-1 Nongseo-dong, Giheung-gu, Yongin-si, Gyeonggi-do 446-712 (Korea, Republic of)

2013-04-15T23:59:59.000Z

451

Basic Research Needs for High Energy Density Laboratory 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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAboutScience ProgramBackground High the cover: Invisible infrared light

452

Sandia National Laboratories: temporal variation of power 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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1developmentturbineredox-activeNational SolartSSL George Wang'sspeed Tidal Energypower

453

Resonant plasma heating below the cyclotron frequencya... Roscoe Whiteb)  

E-Print Network [OSTI]

, University of California, Irvine, California 92697 Zhihong Lin Plasma Physics Laboratory, Princeton consisting of a number of modes. This phenomenon may have relevance for the heating of ions in the solar

Lin, Zhihong

454

New Solicitations | National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

High Energy Density Laboratory Plasmas New Solicitations New Solicitations High Energy Density Laboratory Plasmas (HEDLP) Program New Solicitation The Department of Energy's...

455

Research Areas | National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

High Energy Density Laboratory Plasmas Research Areas Research Areas High Energy Density Laboratory Plasmas (HEDLP) Research Areas During open solicitations proposals are sought...

456

Program Objectives | National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

High Energy Density Laboratory Plasmas Program Objectives Program Objectives High Energy Density Laboratory Plasmas (HEDLP) Program Objectives Support the U.S. scientific...

457

Effect of Lithium PFC Coatings on NSTX Density Control  

SciTech Connect (OSTI)

Lithium coatings on the graphite plasma facing components (PFCs) in NSTX are being investigated as a tool for density profile control and reducing the recycling of hydrogen isotopes. Repeated lithium pellet injection into Center Stack Limited and Lower Single Null Ohmic Helium Discharges were used to coat graphite surfaces that had been pre-conditioned with Ohmic Helium Discharges of the same shape to reduce their contribution to hydrogen isotope recycling. The following deuterium NBI reference discharges exhibited a reduction in density by a factor of about 3 for limited and 2 for diverted plasmas respectively, and peaked density profiles. Recently, a lithium evaporator has been used to apply thin coatings on conditioned and unconditioned PFCs. Effects on the plasma density and the impurities were obtained by pre-conditioning the PFCs with ohmic helium discharges, and performing the first deuterium NBI discharge as soon as possible after applying the lithium coating.

Kugel, H W; Bell, M G; Bush, C; Gates, D; Gray, T; Kaita, R; Leblanc, B; Maingi, R; Majeski, R; Mansfield, D; Mueller, D; Raman, R; Roquemore, A L; Sabbagh, S; Skinner, C H; Soukhanovskii, V; Stevenson, T; Zakharov, L

2006-08-21T23:59:59.000Z

458

A plasma process monitor/control system  

SciTech Connect (OSTI)

Sandia National Laboratories has developed a system to monitor plasma processes for control of industrial applications. The system is designed to act as a fully automated, sand-alone process monitor during printed wiring board and semiconductor production runs. The monitor routinely performs data collection, analysis, process identification, and error detection/correction without the need for human intervention. The monitor can also be used in research mode to allow process engineers to gather additional information about plasma processes. The plasma monitor can perform real-time control of support systems known to influence plasma behavior. The monitor can also signal personnel to modify plasma parameters when the system is operating outside of desired specifications and requires human assistance. A notification protocol can be selected for conditions detected in the plasma process. The Plasma Process Monitor/Control System consists of a computer running software developed by Sandia National Laboratories, a commercially available spectrophotometer equipped with a charge-coupled device camera, an input/output device, and a fiber optic cable.

Stevenson, J.O.; Ward, P.P.; Smith, M.L. [Sandia National Labs., Albuquerque, NM (United States); Markle, R.J. [Advanced Micro Devices, Inc., Austin, TX (United States)

1997-08-01T23:59:59.000Z

459

Direct measurements of the ionization profile in krypton helicon plasmas  

SciTech Connect (OSTI)

Helicons are efficient plasma sources, capable of producing plasma densities of 10{sup 19} m{sup -3} with only 100 s W of input rf power. There are often steep density gradients in both the neutral density and plasma density, resulting in a fully ionized core a few cm wide surrounded by a weakly ionized plasma. The ionization profile is usually not well known because the neutral density is typically inferred from indirect spectroscopic measurements or from edge pressure gauge measurements. We have developed a two photon absorption laser induced fluorescence (TALIF) diagnostic capable of directly measuring the neutral density profile. We use TALIF in conjunction with a Langmuir probe to measure the ionization fraction profile as a function of driving frequency, magnetic field, and input power. It is found that when the frequency of the driving wave is greater than a critical frequency, f{sub c} Almost-Equal-To 3f{sub lh}, where f{sub lh} is the lower hybrid frequency at the antenna, the ionization fraction is small (0.1%) and the plasma density low (10{sup 17} m{sup -3}). As the axial magnetic field is increased, or, equivalently, the driving frequency decreased, a transition is observed. The plasma density increases by a factor of 10 or more, the plasma density profile becomes strongly peaked, the neutral density profile becomes strongly hollow, and the ionization fraction in the core approaches 100%. Neutral depletion in the core can be caused by a number of mechanisms. We find that in these experiments the depletion is due primarily to plasma pressure and neutral pumping.

Magee, R. M.; Galante, M. E.; McCarren, D. W.; Scime, E. E. [Department of Physics, West Virginia University, Morgantown, West Virginia 26506 (United States); Gulbrandsen, N. [Department of Physics and Technology, Faculty of Science, University of Tromso, N-9037 Tromso (Norway)

2012-12-15T23:59:59.000Z

460

The role of higher-order modes on the electromagnetic whistler-cyclotron wave fluctuations of thermal and non-thermal plasmas  

SciTech Connect (OSTI)

Two fundamental challenging problems of laboratory and astrophysical plasmas are the understanding of the relaxation of a collisionless plasmas with nearly isotropic velocity distribution functions and the resultant state of nearly equipartition energy density with electromagnetic plasma turbulence. Here, we present the results of a study which shows the role that higher-order-modes play in limiting the electromagnetic whistler-like fluctuations in a thermal and non-thermal plasma. Our main results show that for a thermal plasma the magnetic fluctuations are confined by regions that are bounded by the least-damped higher order modes. We further show that the zone where the whistler-cyclotron normal modes merges the electromagnetic fluctuations shifts to longer wavelengths as the ?{sub e} increases. This merging zone has been interpreted as the beginning of the region where the whistler-cyclotron waves losses their identity and become heavily damped while merging with the fluctuations. Our results further indicate that in the case of nonthermal plasmas, the higher-order modes do not confine the fluctuations due to the effective higher-temperature effects and the excess of suprathermal plasma particles. The analysis presented here considers the second-order theory of fluctuations and the dispersion relation of weakly transverse fluctuations, with wave vectors parallel to the uniform background magnetic field, in a finite temperature isotropic bi-Maxwellian and Tsallis-kappa-like magnetized electron–proton plasma. Our results indicate that the spontaneously emitted electromagnetic fluctuations are in fact enhanced over these quasi modes suggesting that such modes play an important role in the emission and absorption of electromagnetic fluctuations in thermal or quasi-thermal plasmas.

Viñas, Adolfo F. [NASA Goddard Space Flight Center, Heliophysics Science Division, Geospace Physics Laboratory, Mail Code 673, Greenbelt, Maryland 20771 (United States)] [NASA Goddard Space Flight Center, Heliophysics Science Division, Geospace Physics Laboratory, Mail Code 673, Greenbelt, Maryland 20771 (United States); Moya, Pablo S. [NASA Goddard Space Flight Center, Heliophysics Science Division, Geospace Physics Laboratory, Mail Code 673, Greenbelt, Maryland 20771 (United States) [NASA Goddard Space Flight Center, Heliophysics Science Division, Geospace Physics Laboratory, Mail Code 673, Greenbelt, Maryland 20771 (United States); Department of Physics, Catholic University of America, Washington DC, District of Columbia 20064 (United States); Navarro, Roberto [Departamento de Física, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago (Chile)] [Departamento de Física, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago (Chile); Araneda, Jaime A. [Departamento de Física, Universidad de Concepción Facultad de Ciencias Físicas y Matemáticas, Casilla 160-C, Concepción (Chile)] [Departamento de Física, Universidad de Concepción Facultad de Ciencias Físicas y Matemáticas, Casilla 160-C, Concepción (Chile)

2014-01-15T23:59:59.000Z

Note: This page contains sample records for the topic "density laboratory plasmas" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

National Renewable Energy Laboratory  

E-Print Network [OSTI]

National Renewable Energy Laboratory Innovation for Our Energy Future ponsorship Format Reversed Color:White rtical Format Reversed-A ertical Format Reversed-B National Renewable Energy Laboratory National Renewable Energy Laboratory Innovation for Our Energy Future National Renewable Energy Laboratory

462

Shock compression of low-density foams  

SciTech Connect (OSTI)

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.

Holmes, N.C.

1993-07-01T23:59:59.000Z

463

Controlling Plasma Instabilities: A Multidisciplinary Approach Bedros Afeyan  

E-Print Network [OSTI]

at the University of Maryland, at Lawrence Livermore National Laboratory and at UC Davis, Livermore. His work has e2 me e2 c 1 137 A NIF Hohlraum is a Laser-Plasma Instability (LPI) Candy Store Non of the plasma conditions or interaction modalities that are dominant on the NIF were ever accessed on Nova or Omega. Its

Levi, Anthony F. J.

464

Spectroscopic Determination of the Magnetic Fields in Exploding Wire and X-pinch Plasmas  

SciTech Connect (OSTI)

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.

Hammer, David A.

2013-12-19T23:59:59.000Z

465

Materials Design Laboratory | Argonne National Laboratory  

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

Design Laboratory, scheduled for completion in FY 2020, is designed to meet U.S. Green Building Council Leadership in Energy and Environmental Design (LEED) Gold...

466

Pair densities in density functional theory  

E-Print Network [OSTI]

The exact interaction energy of a many-electron system is determined by the electron pair density, which is not well-approximated in standard Kohn-Sham density functional models. Here we study the (complicated but well-defined) exact universal map from density to pair density. We show that many common functionals, including the most basic version of the LDA (Dirac exchange with no correlation contribution), arise from particular approximations of this map. We develop an algorithm to compute the map numerically, and apply it to one-parameter families {a*rho(a*x)} of one-dimensional homogeneous and inhomogeneous single-particle densities. We observe that the pair density develops remarkable multiscale patterns which strongly depend on both the particle number and the "width" 1/a of the single-particle density. The simulation results are confirmed by rigorous asymptotic results in the limiting regimes a>>1 and a<<1. For one-dimensional homogeneous systems, we show that the whole spectrum of patterns is rep...

Chen, Huajie

2015-01-01T23:59:59.000Z

467

Oblique interactions of dust density waves  

SciTech Connect (OSTI)

Self-excited dust density waves (DDWs) are studied in a striped electrode device. In addition to the usual perpendicularly (with respect to the electrode) propagating DDWs, which have been frequently observed in dusty plasma experiments on the ground, a low-frequency oblique mode is also observed. This low-frequency oblique DDW has a frequency much lower than the dust plasma frequency and its spontaneous excitation is observed even with a very low dust density. It is found that the low-frequency oblique mode can exist either separately or together with the usual perpendicular mode. In the latter case, a new mode arises as a result of the interactions between the perpendicular and the oblique modes. The experiments show that these three modes satisfy the wave coupling conditions in both the frequencies and the wave-vectors.

Wang, Zhelchui [Los Alamos National Laboratory; Li, Yang - Fang [MAX-PLANCK INSTITUTE; Hou, Lujing [MAX-PLANCK INSTITUTE; Jiang, Ke [MAX-PLANCK INSTITUTE; Wu, De - Jin [CHINA; Thomas, Hubertus M [MAX-PLANCK INSTITUTE; Morfill, Gregor E [MAX-PLANCK INSTITUTE

2010-01-01T23:59:59.000Z

468

Plasma wake field XUV radiation source  

DOE Patents [OSTI]

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.

Prono, Daniel S. (Los Alamos, NM); Jones, Michael E. (Los Alamos, NM)

1997-01-01T23:59:59.000Z

469

Optimized ECR plasma apparatus with varied microwave window thickness  

DOE Patents [OSTI]

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.

Berry, L.A.

1995-11-14T23:59:59.000Z

470

ECR apparatus with magnetic coil for plasma refractive index control  

DOE Patents [OSTI]

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.

Berry, L.A.

1994-04-26T23:59:59.000Z

471

Self-consistent quasiparticle model for quark-gluon plasma  

E-Print Network [OSTI]

Here we present a self-consistent quasi-particle model for quark-gluon plasma and apply it to explain the non-ideal behaviour seen in lattice simulations. The basic idea, borrowed from electrodynamic plasma, is that the gluons acquire mass as it propagates through plasma due to collective effects and is approximately equal to the plasma frequency. The statistical mechanics and thermodynamics of such a system is studied by treating it as an ideal gas of massive gluons. Since mass or plasma frequency depends on density, which itself is a thermodynamic quantity, the whole problem need to be solved self-consistently.

Vishnu M. Bannur

2006-09-19T23:59:59.000Z

472

Quantum plasma effects in the classical regime  

E-Print Network [OSTI]

For quantum effects to be significant in plasmas it is often assumed that the temperature over density ratio must be small. In this paper we challenge this assumption by considering the contribution to the dynamics from the electron spin properties. As a starting point we consider a multicomponent plasma model, where electrons with spin up and spin down are regarded as different fluids. By studying the propagation of Alfv\\'{e}n wave solitons we demonstrate that quantum effects can survive in a relatively high-temperature plasma. The consequences of our results are discussed.

G. Brodin; M. Marklund; G. Manfredi

2008-02-01T23:59:59.000Z

473

Langmuir Probe Measurements in Plasma Shadows  

SciTech Connect (OSTI)

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.

Waldmann, O. [Max-Planck-Institut fuer Plasmaphysik, TI Greifswald, Wendelsteinstr. 1, 17491 Greifswald, EURATOM Association (Germany); Koch, B.; Fussmann, G. [Max-Planck-Institut fuer Plasmaphysik, TI Greifswald, Wendelsteinstr. 1, 17491 Greifswald, EURATOM Association (Germany); Humboldt-Universitaet zu Berlin, Institut fuer Physik, PLA, Newtonstr. 15, 12489 Berlin (Germany)

2006-01-15T23:59:59.000Z

474

Dissipative phenomena in quark-gluon plasmas  

SciTech Connect (OSTI)

Transport coefficients of small-chemical-potential quark-gluon plasmas are estimated and dissipative corrections to the scaling hydrodynamic equations for ultrarelativistic nuclear collisions are studied. The absence of heat-conduction phenomena is clarified. Lower and upper bounds on the shear-viscosity coefficient are derived. QCD phenomenology is used to estimate effects of color-electric and -magnetic shielding, and nonperturbative antiscreening. Bulk viscosity associated with the plasma-to-hadron transition is estimated within the relaxation-time approximation. Finally, effects of dissipative phenomena on the relation between initial energy density and final rapidity density are estimated.

Danielewicz, P.; Gyulassy, M.

1985-01-01T23:59:59.000Z

475

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinanInformation Desert Southwest RegionatSearch Welcome to theNews & Blog »Physics PhysicsWeekPlasma

476

Grid adaptation for multiscale plasma simulations  

E-Print Network [OSTI]

Grid adaptation for multiscale plasma simulations Gian Luca Delzanno Los Alamos National Laboratory In collaboration with L. Chacon and J.M. Finn #12;delzanno@lanl.gov Outline · Introduction and motivation · Grid tests · New directions · Conclusions #12;delzanno@lanl.gov Outline · Introduction and motivation · Grid

Ito, Atsushi

477

Tritium plasma experiment: Parameters and potentials for fusion plasma-wall interaction studies  

SciTech Connect (OSTI)

The tritium plasma experiment (TPE) is a unique facility devoted to experiments on the behavior of deuterium/tritium in toxic (e.g., beryllium) and radioactive materials for fusion plasma-wall interaction studies. A Langmuir probe was added to the system to characterize the plasma conditions in TPE. With this new diagnostic, we found the achievable electron temperature ranged from 5.0 to 10.0 eV, the electron density varied from 5.0 x 10{sup 16} to 2.5 x 10{sup 18} m{sup -3}, and the ion flux density varied between 5.0 x 10{sup 20} to 2.5 x 10{sup 22} m{sup -2} s{sup -1} along the centerline of the plasma. A comparison of these plasma parameters with the conditions expected for the plasma facing components (PFCs) in ITER shows that TPE is capable of achieving most ({approx}800 m{sup 2} of 850 m{sup 2} total PFCs area) of the expected ion flux density and electron density conditions.

Shimada, Masashi; Sharpe, J. Phillip [Fusion Safety Program, Idaho National Laboratory, Idaho Falls, Idaho 83415 (United States); Kolasinski, Robert D.; Causey, Rion A. [Hydrogen and Metallurgical Science Department, Sandia National Laboratories, Livermore, California 94551 (United States)

2011-08-15T23:59:59.000Z

478

Ris National Laboratory Wind Energy Department  

E-Print Network [OSTI]

and the wind power density 36 (Troen & Petersen, 1989). In screening for potential offshore wind 37farm sitesRisø National Laboratory Postprint Wind Energy Department Year 2006 Paper: www.risoe.dk/rispubl/art/2006_96.pdf Wind resource assessment from C-band SAR Merete Bruun Christiansen a, Wolfgang Koch b

479

High resolution soft x-ray spectroscopy of low Z K-shell emission from laser-produced plasmas  

SciTech Connect (OSTI)

A large radius, R = 44.3 m, High Resolution Grating Spectrometer (HRGS) with 2400 line/mm variable line spacing has been designed for laser-produced plasma experiments conducted at the Lawrence Livermore National Laboratory Jupiter Laser Facility. The instrument has been run with a low-noise, charge-coupled device detector to record high signal-to-noise spectra in the 10-50 {angstrom} wavelength range. The instrument can be run with a 10-20 {micro}m wide slit to achieve the best spectral resolving power, approaching 1000 and similar to crystal spectrometers at 12-20 {angstrom}, or in slitless operation with a small symmetrical emission source. We describe preliminary spectra emitted from various H-like and He-like low Z ion plasmas heated by 100-500 ps (FWHM), 527 nm wavelength laser pulses. This instrument can be developed as a useful spectroscopy platform relevant to laboratory-based astrophysics as well as high energy density plasma studies.

Dunn, J; Magee, E W; Shepherd, R; Chen, H; Hansen, S B; Moon, S J; Brown, G V; Gu, M; Beiersdorfer, P; Purvis, M A

2008-05-21T23:59:59.000Z

480

PISCES Program: Plasma-materials interactions and edge-plasma physics research. Progress report, 1991--1992  

SciTech Connect (OSTI)

This program investigates and characterizes the behavior of materials under plasma bombordment, in divertor regions. The PISCES facility is used to study divertor and plasma edge management concepts (in particular gas target divertors), as well as edge plasma turbulence and transport. The plasma source consists of a hot LaB{sub 6} cathode with an annular, water-cooled anode and attached drift tube. This cross sectional area of the plasma can be adjusted between 3 and 10 cm. A fast scanning diagnostic probe system was used for mapping plasma density profiles during biased limiter and divertor simulation experiments. Some experimental data are given on: (1) materials and surface physics, (2) edge plasma physics, and (3) a theoretical analysis of edge plasma modelling.

Conn, R.W.; Hirooka, Y.

1992-07-01T23:59:59.000Z