Powered by Deep Web Technologies
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.


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

High Energy Density Laboratory Plasmas Program | National Nuclear Security  

National Nuclear Security Administration (NNSA)

Program | National Nuclear Security Program | National Nuclear Security Administration Our Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing Our Infrastructure Continuing Management Reform Countering Nuclear Terrorism About Us Our Programs Our History Who We Are Our Leadership Our Locations Budget Our Operations Media Room Congressional Testimony Fact Sheets Newsletters Press Releases Speeches Events Social Media Video Gallery Photo Gallery NNSA Archive Federal Employment Apply for Our Jobs Our Jobs Working at NNSA Blog High Energy Density Laboratory Plasmas Program Home > High Energy Density Laboratory Plasmas Program High Energy Density Laboratory Plasmas Program Steady advances in increasing the energy, power, and brightness of lasers and particle beams and advances in pulsed power systems have made possible

3

High Energy Density Laboratory Plasmas | National Nuclear Security  

National Nuclear Security Administration (NNSA)

| National Nuclear Security | National Nuclear Security Administration Our Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing Our Infrastructure Continuing Management Reform Countering Nuclear Terrorism About Us Our Programs Our History Who We Are Our Leadership Our Locations Budget Our Operations Media Room Congressional Testimony Fact Sheets Newsletters Press Releases Speeches Events Social Media Video Gallery Photo Gallery NNSA Archive Federal Employment Apply for Our Jobs Our Jobs Working at NNSA Blog HEDLP High Energy Density Laboratory Plasmas Home > About Us > Our Programs > Defense Programs > Office of Research, Development, Test, and Evaluation > University Partnerships / Academic Alliances > High Energy Density Laboratory Plasmas

4

Activities of the High Energy Density Laboratory Plasmas  

E-Print Network [OSTI]

Activities of the High Energy Density Laboratory Plasmas FESAC Panel R. Betti FPA Meeting December #12;F. Beg (UCSD) B. Remington (LLNL) R. Betti (UR) (chair) R. Davidson (Princeton) P. Drake (U. Betti (UR) D. Hammer (Cornell) G. Logan (LBNL) D. Meyerhofer (UR) J. Sethian (NRL) R. Siemon (UNR) IFE

5

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

6

Laboratory Density Functionals  

E-Print Network [OSTI]

We compare several definitions of the density of a self-bound system, such as a nucleus, in relation with its center-of-mass zero-point motion. A trivial deconvolution relates the internal density to the density defined in the laboratory frame. This result is useful for the practical definition of density functionals.

B. G. Giraud

2007-07-26T23:59:59.000Z

7

Inner magnetosphere plasma densities  

E-Print Network [OSTI]

The radio plasma imager (RPI) on the IMAGE satellite performs radio sounding in the magnetosphere, transmitting coded signals stepping through the frequency range of interest and receiving the returned echoes. The measurements provide the echo amplitude as a function of frequency and echo delay time on a so-called plasmagram. A newly developed algorithm inverts THE echo traces on a plasmagram to electron density spatial distributions. Based on these observed density distributions, an empirical model is constructed to describe the two-dimensional density distribution in the inner magnetosphere.

Reinisch, B W

2002-01-01T23:59:59.000Z

8

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

9

High-Energy-Density Plasmas, Fluids  

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

High-Energy-Density Plasmas, Fluids High-Energy-Density Plasmas, Fluids /science-innovation/_assets/images/icon-science.jpg High-Energy-Density Plasmas, Fluids National security depends on science and technology. The United States relies on Los Alamos National Laboratory for the best of both. No place on Earth pursues a broader array of world-class scientific endeavors. TRIDENT target chamber Sasi Palaniyappan, right, and Rahul Shah left inside a target chamber where the TRIDENT short pulse laser is aimed at a very thin diamond- foil target, a fraction of a micrometer thick. The laser delivers a power on target of 150 Terawatts focused into a 7 micrometer spot, yielding laser brilliance over 100 times more intense than needed to make the target electrons fully relativistic. These experiments test novel methods of producing intense

10

H IGHLIGHTS PRINCETON PLASMA PHYSICS LABORATORY  

E-Print Network [OSTI]

H IGHLIGHTS PRINCETON PLASMA PHYSICS LABORATORY Princeton Plasma Physics Laboratory Fiscal Year 1996 #12; This publication highlights activities at the Princeton Plasma Physics Laboratory for fiscal support, see the PPPL fiscal year 1996 Annual Report. About PPPL Established in 1951, the Princeton Plasma

11

PPPL Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

PPPL Princeton Plasma Physics Laboratory PROCEDURE GEN-034 Rev 0 page 1 of 4 Effective Date: Dec. 20, 2012 Initiated by: Head, Technology Transfer, Patents & Publications Subject: Sharing PPPL or modified by PPPL staff for use on PPPL operating experiments, analyzing experimental data, engineering

Princeton Plasma Physics Laboratory

12

Princeton Plasma Physics laboratory weekly  

E-Print Network [OSTI]

At PPPL This Week Princeton Plasma Physics laboratory weekly DECEMBER 9, 2013 continued on page 2 ......... page 6 Cafe@PPPL Menu ... page 7 INsIde... page 1 of 7 MONDAY, DEC. 9MONDAY, DEC. 9 Group Photo for holiday card 9:45 a.m. Meet in LsB Lobby All Employees TUESDAY, DEC. 10TUESDAY, DEC. 10 PPPl colloquium

13

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

14

COLLOQUIUM: "Laboratory Dynamos" | Princeton Plasma Physics Lab  

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

video platform video management video solutionsvideo player Colloquium Committee: The Princeton Plasma Physics Laboratory 2014-2015 Colloquium Committee is comprised of the...

15

Laboratory Director PRINCETON PLASMA PHYSICS LABORATORY  

E-Print Network [OSTI]

.D. Levine Dep: R. Sheneman Human Resources Director: S.E. Murphy­ LaMarche Best Practices and Outreach Head Projects: HTX, MNX,OSOR Beam Dynamics and Non-Neutral Plasmas R.C. Davidson Best Practices J. Graham Environmental Services Division R. Sheneman Accounting A.F. Bleach Procurement R. Templon Mechanical P

Princeton Plasma Physics Laboratory

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

Plasma probe characteristics in low density hydrogen pulsed plasmas  

E-Print Network [OSTI]

Probe theories are only applicable in the regime where the probe's perturbation of the plasma can be neglected. However, it is not always possible to know, a priori, that a particular probe theory can be successfully applied, especially in low density plasmas. This is especially difficult in the case of transient, low density plasmas. Here, we applied probe diagnostics in combination with a 2D particle-in-cell model, to an experiment with a pulsed low density hydrogen plasma. The calculations took into account the full chamber geometry, including the plasma probe as an electrode in the chamber. It was found that the simulations reproduce the time evolution of the probe IV characteristics with good accuracy. The disagreement between the simulated and probe measured plasma density is attributed to the limited applicability of probe theory to measurements of low density pulsed plasmas. Indeed, in the case studied here, probe measurements would lead to a large overestimate of the plasma density. In contrast, the ...

Astakhov, D I; Lee, C J; Ivanov, V V; Krivtsun, V M; Zotovich, A I; Zyryanov, S M; Lopaev, D V; Bijkerk, F

2014-01-01T23:59:59.000Z

18

ASSOCIATED LABORATORY PLASMA PHYSICS AND ENGINEERING  

E-Print Network [OSTI]

Units of excellence in Europe, in the fields of Nuclear Fusion, Plasma Physics and Technologies in the frame of the so-called Broader Approach to Fusion Energy; · Collaboration on Nuclear Fusion the present apparatus and Laboratories: Tokamak ISTTOK, Multi-TeraWatt Laser System, Laboratory of Microwave

Lisboa, Universidade Técnica de

19

Princeton Plasma Physics Laboratory NSTX Experimental Proposal  

E-Print Network [OSTI]

the optimal sequencing of H-mode, heating, and current ramp rate to reliably access qmin >> 1 at the end/ empirical justification Rapid penetration of the current density during the current ramp phase of a tokamak operation. Such rapid current penetration can be caused by either high plasma resistivity or plasma

Princeton Plasma Physics Laboratory

20

Princeton Plasma Physics Laboratory D-SITE Procedure  

E-Print Network [OSTI]

Refrigerator Operator Attachment 12 ­ NSTX NB Ion Source Operator #12;NSTX PRINCETON PLASMA PHYSICS LABORATORY

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.


21

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

22

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

23

Magnetic Reconnection in Plasmas: a Celestial Phenomenon in the Laboratory  

E-Print Network [OSTI]

Magnetic Reconnection in Plasmas: a Celestial Phenomenon in the Laboratory Jan Egedal MIT Physics Lin, T Phan, M �ieroset (Space Science Laboratory, UC Berkeley) #12;Magnetic Reconnection · A change in magnetic topology in the presence of a plasma Plasma carrying a current Magnetic fields j Consider a small

24

PRINCETON PLASMA PHYSICS LABORATORY This publication highlights activities at the Princeton Plasma Physics Laboratory for fiscal year 1996 --1 October  

E-Print Network [OSTI]

HIGHLIGHTS PRINCETON PLASMA PHYSICS LABORATORY #12;This publication highlights activities at the Princeton Plasma Physics Laboratory for fiscal year 1996 -- 1 October 1995 through 30 September 1996 Established in 1951, the Princeton Plasma Physics Laborato- ry (PPPL) is dedicated to developing

25

Labs at-a-Glance: Princeton Plasma Physics Laboratory | U.S. DOE Office of  

Office of Science (SC) Website

Princeton Plasma Princeton Plasma Physics Laboratory Laboratories Ames Laboratory Argonne National Laboratory Brookhaven National Laboratory Fermi National Accelerator Laboratory Lawrence Berkeley National Laboratory Oak Ridge National Laboratory Pacific Northwest National Laboratory Princeton Plasma Physics Laboratory SLAC National Accelerator Laboratory Thomas Jefferson National Accelerator Facility Laboratory Policy and Evaluation Safety, Security and Infrastructure Laboratory Science Highlights Contact Information Office of Science U.S. Department of Energy 1000 Independence Ave., SW Washington, DC 20585 P: (202) 586-5430 Labs at-a-Glance: Princeton Plasma Physics Laboratory Print Text Size: A A A RSS Feeds FeedbackShare Page Princeton Plasma Physics Laboratory Logo Visit the Princeton Plasma Physics

26

Amplifying Magnetic Fields in High Energy Density Plasmas | U...  

Office of Science (SC) Website

Amplifying Magnetic Fields in High Energy Density Plasmas Fusion Energy Sciences (FES) FES Home About Research Facilities Science Highlights Benefits of FES Funding Opportunities...

27

Plasma and Technology Programme National Laboratory for Sustainable Energy  

E-Print Network [OSTI]

to atmospheric pressure glow DBD [3]. In general, stabilization of #12;3 atmospheric pressure plasma can easily1 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

28

Fusion Ignition Research Experiment Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

Fusion Ignition Research Experiment Dale Meade Princeton Plasma Physics Laboratory Abstract Understanding the properties of high gain (alpha­dominated) fusion plasmas in an advanced toroidal configuration­dominated plasmas in advanced toroidal systems. Technical Challenges for Major Next Steps in Magnetic Fusion Energy

29

Management Alert - Extended Assignments at Princeton Plasma Physics Laboratory  

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

Extended Assignments at Princeton Extended Assignments at Princeton Plasma Physics Laboratory DOE/IG-0864 May 2012 U.S. Department of Energy Office of Inspector General Office of Audits and Inspections Department of Energy Washington, DC 20585 May 17, 2012 MEMORANDUM FOR THE SECRETARY FROM: Gregory H. Friedman Inspector General SUBJECT: INFORMATION: Management Alert on "Extended Assignments at Princeton Plasma Physics Laboratory" BACKGROUND Princeton University operates the Princeton Plasma Physics Laboratory (Princeton) under a contract with the Department of Energy's Office of Science. Princeton works with partners around the world to develop fusion as an energy source. The Laboratory's annual operating costs

30

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

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

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

31

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.

32

Spectroscopy of astrophysical plasmas in the laboratory  

Science Journals Connector (OSTI)

......plasma built for the study (and eventual generation) of nuclear fusion. Tokamaks have plasma parameters (e.g. temperature...atomic physics data are also being calculated at QUB, for input to these modelling codes, to improve the reliability......

F P Keenan; S J Rose

2004-12-01T23:59:59.000Z

33

DENSITY LIMITS IN TOROIDAL PLASMAS MARTIN GREENWALD  

E-Print Network [OSTI]

(RFP) ---- Spheromaks and FRCs · Physics basis for density limit ---- Neutrals ---- Radiation models as fast terminations · Spheromak and FRC don't have density limit data operation at "optimized" density

Greenwald, Martin

34

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

35

3D EMHD reconnection in a laboratory plasma  

Science Journals Connector (OSTI)

In a large laboratory plasma, reconnection of three-dimensional (3D) magnetic fields is studied in the parameter regime of electron magnetohydrodynamics (EMHD). The field topologies are spheromak-like with two-di...

R. L. Stenzel; J. M. Urrutia; M. C. Griskey; K. D. Strohmaier

2001-06-01T23:59:59.000Z

36

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

37

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

38

Measurement of Plasma Density in a Gas-Filled Ionizing Laser Focus.  

E-Print Network [OSTI]

??We use an interferometric method for measuring the plasma density in a laser-induced plasma as a function of time. Any changes in the density within… (more)

Heilmann, Nathan Edward

2012-01-01T23:59:59.000Z

39

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

40

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

Office of Science (SC) Website

Princeton Plasma Physics Laboratory Laboratory Policy (LP) LP Home About Laboratory Appraisal Process FY 2013 Report Cards FY 2012 Report Cards FY 2011 Report Cards Report Card...

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

Doing Business with Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

Princeton, NJ 08543 Telephone (609) 243-2428 Fax (609) 243-2021 -mail U.S. Department of Energy's e http://procurement.pppl.gov List your business in PPPL's supplier database by going to http://procurement.pppl.gov and clicking community. #12;Welcome to PPPL Procurement! The U.S. Department of Energy's Princeton Plasma Physics

42

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

43

Princeton Plasma Physics Laboratory NSTX Machine Proposal  

E-Print Network [OSTI]

conditions, promoting reliability in future experimental operations. 3. Plan: Establish standard HHFW plasma-AD-63) Independent Review Master Equip. List Mod (OP-AD-112) ES&H Review (NEPA, IH, etc) MINOR MODIFICATIONS #12;REVIEWERS (designated by RLM) ATI Test Director Independent Reviewer D-Site Shift Supervisor

Princeton Plasma Physics Laboratory

44

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

45

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

46

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

47

Erik P. Gilson Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

-Gradient Systems Purpose: Applications: Accelerator systems for high energy and nuclear physics applications, high energy density physics, heavy ion fusion, spallation neutron sources, and nuclear waste transmutation-Gradient Transport Systems S #12;Transverse Focusing Frequency, Vacuum Phase Advance, and Normalized Intensity

Gilson, Erik

48

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

49

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

50

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

51

Causal Link of Longitudinal Plasma Density Structure to Vertical Plasma Drift and Atmospheric Tides – A Review  

Science Journals Connector (OSTI)

This chapter reviews recent advances in our understanding of the characteristics and driving mechanisms of the longitudinal plasma density structure in the low-latitude F...region. Various ionospheric observation...

Hyosub Kil; Larry J. Paxton

2011-01-01T23:59:59.000Z

52

Human Plasma Very Low Density Lipoprotein Carries Indian Hedgehog  

Science Journals Connector (OSTI)

Human Plasma Very Low Density Lipoprotein Carries Indian Hedgehog ... At each time point, the viability of the cells was evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide), reduction assay,(20) and cell counting with trypan blue. ...

Karla C. S. Queiroz; René A. Tio; Clark J. Zeebregts; Maarten F. Bijlsma; Felix Zijlstra; Bahram Badlou; Marcel de Vries; Carmen V. Ferreira; C. Arnold Spek; Maikel P. Peppelenbosch; Farhad Rezaee

2010-09-14T23:59:59.000Z

53

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

E-Print Network [OSTI]

of these efforts have been focused on the sheath region of the plasma, but here we will focus on the main plasmaDusty plasma diagnostics methods for charge, electron temperature, and ion density Bin Liu,1 J Q and two plasma parameters, electron temperature Te, and ion density ni, in the main plasma region

Goree, John

54

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

55

OH number densities and plasma jet behavior in atmospheric microwave plasma jets operating with different plasma gases (Ar, Ar/N2, and Ar/O2)  

Science Journals Connector (OSTI)

OH radical number density in multiple atmospheric pressure microwave plasma jets is measured using UV cavity ringdown ... 0–0) band at 308 nm. The plasma cavity was excited by a 2.45 GHz microwave plasma source a...

C. Wang; N. Srivastava

2010-12-01T23:59:59.000Z

56

Microwave interferometer for plasma-density measurement on TMX Upgrade  

SciTech Connect (OSTI)

A four-channel microwave interferometer operating at 140 GHz has been designed for installation on the upgrade to the Tandem Mirror Experiment (TMX Upgrade). The instrument can be used to measure plasma density simultaneously at four locations: by reconnecting the waveguide runs, density can be measured at other locations of interest. The design is an outgrowth of a system used on TMX, but includes some newly developed hardware. An over-mode circular waveguide system is used to transport the signals over long distances with only moderate losses. Several precautions have been taken to limit the effect of possible interference from the electron cyclotron resonant heating (ECRH) system used to heat the plasma. A high-resolution linear phase comparator has been designed that will operate over the wide range of signals expected. A CAMAC-based data-acquisition system provides for automatic data sampling and archival after each shot.

Coffield, F.E.; Stever, R.D.; Lund, N.P.

1981-09-25T23:59:59.000Z

57

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

58

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

59

ENVIRONMENTAL EVALUATION NOTIFICATION FORM Grantee/Contractor Laboratory: Princeton University/Princeton Plasma Physics Laboratory (PPPL)  

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

EVALUATION NOTIFICATION FORM EVALUATION NOTIFICATION FORM Grantee/Contractor Laboratory: Princeton University/Princeton Plasma Physics Laboratory (PPPL) Project! Activity Title: STS-100 Test Stand Experiment NEPA Tracking No.: Type of Funding _ _ --=S=C'---_ _ _ _ _ _ _ _ _ _ _ _ B&R Code: Total Estimated Cost _ _ ---"'$=2=-OO"'-',=OO=O"--_ _ _ _ _ _ _ DOE Cognizant Secretarial Officer (CSO):--'W~il=lia=m~F'-'-.-"=B=r=in=km=a=n'__ _ _ _ _ _ _ _ _ _ _ _ Contractor Project Manager: ____ -_-_--_--_-_--_-_-_ _ _ _ _ Signature: ------------- Contractor NEPA Reviewer: Jerry D. Levine Date: ( S--Q--------f-- /:/1 Signature: "~ ~ ~ Date: I ~lJO I * I. Description of Proposed Action: The proposed action would consist of operation of a 100

60

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

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

Formation of a High?Density Deuterium Plasma Focus  

Science Journals Connector (OSTI)

During the early investigation of the high?energy low?pressure mode of a coaxial hydromagnetic gun a second mode of action was established for large gas fillings. This particular mode previously reported was found to lead to a high?density plasma focus situated at a distance ?1–1.5 cm beyond the face of the center electrode. The plasma focus has the following properties; particle density ? ? 2–3 × 1019/cm3 temperature T ? 1–3 keV time duration t ? 0.2–0.3 ?sec and volume ?15 mm3. Neutron yields >1010/burst and soft x rays are observed. These results are remarkably similar to those reported by Petrov et al. and Filippov et al. of the USSR using a metal wall pinch tube apparatus. The average velocity vz of the current sheath in the gun proper is found to depend on the fourth root of the applied voltage squares divided by the mass density according to the simple ``snowplow'' ``M'' theory. The current sheath is found to be nonplanar and mass pickup by the advancing sheath is nonlinear with radius. The sudden collapse of the radial current sheath toward the axis at the center electrode end is most likely caused by the rapid conversion of stored magnetic energy into radial sheath motion (v? r ? 3.5 × 107 cm/sec) forming in essence a super dense pinch effect.

J. W. Mather

1965-01-01T23:59:59.000Z

62

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...

63

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

E-Print Network [OSTI]

Studies of electron heating on a 6.4 GHz ECR ion source 3.114 GHz Advanced Electron Cyclotron Source-Upgraded (AECR-U).spectra in electron cyclotron resonance ion source plasmas

Noland, Jonathan David

2011-01-01T23:59:59.000Z

64

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.

65

SAND2011-6616A Page 1 Session 2: High Energy Density, Plasmas, Magnetic Fields  

National Nuclear Security Administration (NNSA)

616A 616A Page 1 Session 2: High Energy Density, Plasmas, Magnetic Fields Dynamical Materials Experiments on Sandia's Z Machine: Obtaining Data with High Precision at HED Conditions Thomas R. Mattsson and Seth Root Sandia National Laboratories, Albuquerque, NM USA Summary: The Z machine at Sandia National Laboratories has successfully been used to study a wide range of materials under extreme conditions. In this paper, we will discuss the methodology resulting in high-pressure measurements at multi-Mbar pressures as well as present experimental data for shock compression of poly methyl-pentene, a hydrocarbon plastic. Introduction During the last few years, there has been a notable increase in the interest of high-pressure science. The increase in interest has been driven by the remarkable capabilities of new and improved platforms like

66

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

67

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

68

Three-dimensional, Impulsive Magnetic Reconnection in a Laboratory Plasma  

SciTech Connect (OSTI)

Impulsive, local, 3-D reconnection is identified for the first time in a laboratory current sheet. The events observed in the Magnetic Reconnection Experiment (MRX) are characterized by large local gradients in the third direction and cannot be explained by 2-D models. Detailed measurements show that the ejection of flux rope structures from the current sheet plays a key role in these events. By contrast, even though electromagnetic fluctuations in the lower hybrid frequency range are also observed concurrently with the impulsive behavior, they are not the key physics responsible. A qualitative, 3-D, two-fluid model is proposed to explain the observations. The experimental results may be particularly applicable to space and astrophysical plasmas where impulsive reconnection occurs.

S Dorfman, et al

2013-05-03T23:59:59.000Z

69

Electron Acceleration Experiments by Using a Density-tapered Capillary Plasma Source  

Science Journals Connector (OSTI)

We have developed a density-tapered capillary plasma source for high energy electron generation by using the laser wakefield acceleration, where the dephasing problem will be...

Suk, Hyyong; Nam, Inhyuk; Kim, Minseok; Lee, Seungwoo; Lee, Taehee

70

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

E-Print Network [OSTI]

1 Testimony of Dr. Stewart C. Prager Director, Princeton Plasma Physics Laboratory you for this opportunity to discuss fusion energy. I am Director of the Princeton Plasma Physics Laboratory ­ a Department of Energy national lab, managed by Princeton University, dedicated

71

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

E-Print Network [OSTI]

analysis and diagnostics (collisionality, high flux). · IT: Atmospheric DBD plasma (AC, high collisionalityelectric Probe Applications Laboratory, Hanyang University DiPS (Diversified Plasma Simulator on Edge Plasma & Surface Interactions in S-S Magnetic Fusion May 20-22, 2007 National Institute of Fusion

Princeton Plasma Physics Laboratory

72

Basic Research Needs for High Energy Density Laboratory Physics  

National Nuclear Security Administration (NNSA)

On the cover: On the cover: Invisible infrared light from the 200-trillion watt Trident Laser enters from the bottom to interact with a one-micrometer thick foil target in the center of the photo. The laser pulse produces a plasma - an ionized gas - many times hotter than the center of the sun, which lasts for a trillionth of a second. During this time some electrons from the foil are accelerated to virtually the speed of

73

Relaxation of potential, flows, and density in the edge plasma of CASTOR tokamak  

E-Print Network [OSTI]

Relaxation of potential, flows, and density in the edge plasma of CASTOR tokamak M. Hron1 , V on the CASTOR tokamak. A biased electrode has been used to polarize the edge plasma. The edge plasma potential time in the range of 10 - 30 µs when the electrode biasing is turn off in the CASTOR tokamak

Boyer, Edmond

74

RIS-M-2594 ELECTRON CYCLOTRON RESONANCE HEATING OF A HIGH-DENSITY PLASMA  

E-Print Network [OSTI]

RIS�-M-2594 ELECTRON CYCLOTRON RESONANCE HEATING OF A HIGH-DENSITY PLASMA Flemming Ramskov Hansen Abstract. Various schemes for electron cyclotron resonance heat- ing of tokamak plasmas with the ratio of electron plasma frequen- cy to electron cyclotron frequency, "»pe/^ce* larger than 1 on axis

75

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

76

Experimental investigation of ultraviolet laser induced plasma density and temperature evolution in air  

E-Print Network [OSTI]

and collisional cascade processes for pressures ranging from 40 Torr to 5 atm. A laser shadowgraphy diagnosticExperimental investigation of ultraviolet laser induced plasma density and temperature evolution July 2008 We present measurements and analysis of laser induced plasma neutral densities

Scharer, John E.

77

Center at plasma laboratory wins $12 million grant for fusion research |  

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

Center at plasma laboratory wins $12 million grant for fusion research Center at plasma laboratory wins $12 million grant for fusion research By John Greenwald October 10, 2012 Tweet Widget Facebook Like Google Plus One C.S. Chang, who heads the Center for Edge Physics Simulation at the Princeton Plasma Physics Lab, stands by a high-performance computer cluster at the laboratory. With a $12.25 million grant from the U.S. Department of Energy, Chang and other researchers will develop computer codes to simulate a key component of the plasma that fuels fusion energy. (Photo by Elle Starkman, PPPL Office of Communications) C.S. Chang, who heads the Center for Edge Physics Simulation at the Princeton Plasma Physics Lab, stands by a high-performance computer cluster at the laboratory. With a $12.25 million grant from the U.S. Department of

78

Dispersion relation and Landau damping of waves in high-energy density plasmas  

Science Journals Connector (OSTI)

We present a theoretical investigation on the propagation of electromagnetic waves and electron plasma waves in high energy density plasmas using the covariant Wigner function approach. Based on the covariant Wigner function and Dirac equation, a relativistic quantum kinetic model is established to describe the physical processes in high-energy density plasmas. With the zero-temperature Fermi–Dirac distribution, the dispersion relation and Landau damping of waves containing the relativistic quantum corrected terms are derived. The relativistic quantum corrections to the dispersion relation and Landau damping are analyzed by comparing our results with those obtained in classical and non-relativistic quantum plasmas. We provide a detailed discussion on the Landau damping obtained in classical plasmas, non-relativistic Fermi plasmas and relativistic Fermi plasmas. The contributions of the Bohm potential, the Fermi statistics pressure and relativistic effects to the dispersion relation and Landau damping of waves are quantitatively calculated with real plasma parameters.

Jun Zhu; Peiyong Ji

2012-01-01T23:59:59.000Z

79

Energetic particle production, cavition formation, and nonlinear development at a plasma density maximum  

SciTech Connect (OSTI)

We have investigated several phenomena of importance to laser-plasma interactions. In our studies, these are modeled by microwave and rf-plasma interactions. Our focus has been on resonant absorption of intense electromagnetic radiation at the plasma critical layer. Electron plasma wave (EPW) growth and caviton formation have been shown to be most efficient for shallow density gradients at the critical layer, where EPW convection losses are minimized. EPW electric field energies of 5000 times the plasma thermal energy, and energetic electron tails out to 5000T{sub e}, have been observed at the top of an inverse parabolic density profile. Ions receive delta-function-like impulses from localized electron plasma waves and wave-breaking electron ejection; the disruption of the ion fluid can only partially be described by the ponderomotive force. Our attempt is to test and illuminate some of the fundamental concepts of strong turbulence and EM wave-plasma interaction. 7 refs.

Wong, A.Y.; Bauer, B.S. (California Univ., Los Angeles, CA (USA). Dept. of Physics)

1990-09-04T23:59:59.000Z

80

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

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

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...

82

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

83

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

84

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

85

Using Radio Waves to Control Fusion Plasma Density  

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

simulation shows turbulent density fluctuations in the core of the Alcator C-Mod tokamak during strong electron heating. Image: Darin Ernst, MIT Recent fusion experiments on...

86

E-Print Network 3.0 - angular momentum densities Sample Search...  

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

required determine whether torque density will applied plasma determine... minority ion-cyclotron heating, even though ... Source: Princeton Plasma Physics Laboratory, Theory...

87

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

88

OP-XP-834 1 / 9 Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

the present run have demonstrated a scenario where this mode is reliably triggered; the recipe has two-mode reactor tokamak plasma. For instance, the 3/2 NTM will result in a ~20% confinement degradation in ITER the focused on, both in terms of devoted XPs, and from large-scale piggyback analysis. The 3/2 mode, however

Princeton Plasma Physics Laboratory

89

Density-dependent response of an ultracold plasma to few-cycle radio-frequency pulses  

Science Journals Connector (OSTI)

Ultracold neutral plasmas exhibit a density-dependent resonant response to applied radio-frequency (rf) fields in the frequency range of several to hundreds of megahertz for achievable densities. We have conducted measurements where short bursts of an rf fieldwere applied to these plasmas, with pulse durations as short as two cycles. We still observed a density-dependent resonant response to these short pulses, but the time scale of the response is too short to be consistent with local heating of electrons in the plasma from collisions under a range of experimental parameters. Instead, our results are consistent with rapid energy transfer to individual electrons from electric fields resulting from an overall displacement of the electron cloud from the ions during the collective motion of the electrons. This collective motion was also observed by applying two sharp electric field pulses separated in time to the plasma. These measurements demonstrate the importance of collective motion in the energy transport in these systems.

Truman M. Wilson; Wei-Ting Chen; Jacob L. Roberts

2013-01-14T23:59:59.000Z

90

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

91

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

92

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

93

U.S. Department of energy'S Princeton Plasma Physics laboratory  

E-Print Network [OSTI]

Princeton, nJ 08543 Fax (609) 243-2021 e-mail ppplproc@pppl.gov List your business in PPPL's supplier database by going to http://procurement.pppl.gov and clicking on the "Supplier Information Form" link. Your listing will be accessible to the Laboratory's entire requisitioner community. Doing business with PPPL

94

DERIVING PLASMA DENSITIES AND ELEMENTAL ABUNDANCES FROM SERTS DIFFERENTIAL EMISSION MEASURE ANALYSIS  

SciTech Connect (OSTI)

We use high-resolution spectral emission line data obtained by the SERTS instrument during three rocket flights to demonstrate a new approach for constraining electron densities of solar active region plasma. We apply differential emission measure (DEM) forward-fitting techniques to characterize the multithermal solar plasma producing the observed EUV spectra, with constraints on the high-temperature plasma from the Yohkoh Soft X-ray Telescope. In this iterative process, we compare line intensities predicted by an input source distribution to observed line intensities for multiple iron ion species, and search a broad range of densities to optimize {chi}{sup 2} simultaneously for the many available density-sensitive lines. This produces a density weighted by the DEM, which appears to be useful for characterizing the bulk of the emitting plasma over a significant range of temperature. This 'DEM-weighted density' technique is complementary to the use of density-sensitive line ratios and less affected by uncertainties in atomic data and ionization fraction for any specific line. Once the DEM shape and the DEM-weighted density have been established from the iron lines, the relative elemental abundances can be determined for other lines in the spectrum. We have also identified spectral lines in the SERTS wavelength range that may be problematic.

Schmelz, J. T.; Kimble, J. A. [Physics Department, University of Memphis, Memphis, TN 38152 (United States); Saba, J. L. R., E-mail: jschmelz@memphis.edu [Astronomy Department, University of Maryland, College Park, MD 20742 (United States)

2012-09-20T23:59:59.000Z

95

Observation of Ion Acceleration and Heating during Collisionless Magnetic Reconnection in a Laboratory Plasma  

Office of Scientific and Technical Information (OSTI)

Prepared for the U.S. Department of Energy under Contract Prepared for the U.S. Department of Energy under Contract DE-AC02-09CH11466. Princeton Plasma Physics Laboratory PPPL- 4835 PPPL- 4835 Observation of Ion Acceleration and Heating during Collisionless Magnetic Reconnection in a Laboratory Plasma December, 2012 Jongsoo Yoo, Masaaki Yamada, HantaoJi and Clayton E. Myers Princeton Plasma Physics Laboratory Report Disclaimers Full Legal Disclaimer This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, nor any of their contractors, subcontractors or their employees, makes any

96

At Princeton Plasma Physics Laboratory, buying small is a big win |  

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

At Princeton Plasma Physics Laboratory, buying small is a big win At Princeton Plasma Physics Laboratory, buying small is a big win By Gale Scott May 23, 2011 Tweet Widget Facebook Like Google Plus One When scientists at the U.S. Department of Energy's Princeton Plasma Physics Laboratory (PPPL) needed metal flanges for a specialized piece of equipment, Principal Buyer Arlene White could have ordered them from a range of major manufacturers. Instead, the $150,000 order went to Zenex Precision Products, a small, family-owned machine shop in Paterson, N.J. The company's price was competitive and the quality of the product was excellent. For White, equally important was the fact that the company has only a dozen or so employees and is located in an economically depressed community. "We've bypassed major large companies to buy from them," White said.

97

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.

98

Ris National Laboratory Optics and Plasma Research Department  

E-Print Network [OSTI]

region with spatially localized sources of particles and heat outside which losses due to motion along in positively skewed and flattened single-point probability distribution functions of particle density with the turbulence bursts are relaxation oscillations in the particle and heat confinement as well as in the kinetic

99

Application of high?resolution interferometry to plasma density measurements on TEXT?Upgrade  

Science Journals Connector (OSTI)

High?resolution interferometry using far?infrared laser radiation is employed on TEXT?Upgrade to measure the spatial and temporal evolution of the electron density profile as well as small?scale perturbations. Perturbations to the electron density induced by naturally occurring sawtooth oscillations or externally imposed gas modulations can be used to ascertain the local particle flux and transport coefficients in the plasma interior. Density islands associated with Mirnov activity can also be resolved providing detailed information on the density profile at island X and O points. Implementation of a second orthogonal view will allow accurate determination of the density profile in the various asymmetric plasma configurations of TEXT?Upgrade.

D. L. Brower; Y. Jiang; W. A. Peebles; S. Burns; N. C. Luhmann Jr.

1992-01-01T23:59:59.000Z

100

Plasma devices to guide and collimate a high density of MeV electrons  

Science Journals Connector (OSTI)

... energetic beams will revolutionize their applications. Here we report high-conductivity devices consisting of transient plasmas that increase the energy density of MeV electrons generated in laser–matter interactions by more ... MeV electrons generated in laser–matter interactions by more than one order of magnitude. A plasma fibre created on a hollow-cone target guides and collimates electrons in a manner akin ...

R. Kodama; Y. Sentoku; Z. L. Chen; G. R. Kumar; S. P. Hatchett; Y. Toyama; T. E. Cowan; R. R Freeman; J. Fuchs; Y. Izawa; M. H. Key; Y. Kitagawa; K. Kondo; T. Matsuoka; H. Nakamura; M. Nakatsutsumi; P. A. Norreys; T. Norimatsu; R. A. Snavely; R. B. Stephens; M. Tampo; K. A. Tanaka; T. Yabuuchi

2004-12-23T23:59:59.000Z

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.


101

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

102

Control of ion density distribution by magnetic traps for plasma electrons  

SciTech Connect (OSTI)

The effect of a magnetic field of two magnetic coils on the ion current density distribution in the setup for low-temperature plasma deposition is investigated. The substrate of 400 mm diameter is placed at a distance of 325 mm from the plasma duct exit, with the two magnetic coils mounted symmetrically under the substrate at a distance of 140 mm relative to the substrate centre. A planar probe is used to measure the ion current density distribution along the plasma flux cross-sections at distances of 150, 230, and 325 mm from the plasma duct exit. It is shown that the magnetic field strongly affects the ion current density distribution. Transparent plastic films are used to investigate qualitatively the ion density distribution profiles and the effect of the magnetic field. A theoretical model is developed to describe the interaction of the ion fluxes with the negative space charge regions associated with the magnetic trapping of the plasma electrons. Theoretical results are compared with the experimental measurements, and a reasonable agreement is demonstrated.

Baranov, Oleg; Romanov, Maxim [Plasma Laboratory, National Aerospace University 'KhAI,' Kharkov 61070 (Ukraine); Fang Jinghua [Plasma Nanoscience Centre Australia (PNCA), CSIRO Materials Science and Engineering, P.O. Box 218, Lindfield, New South Wales 2070 (Australia); School of Physics, University of Melbourne, Parkville, VIC 3010 (Australia); Cvelbar, Uros [Jozef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana (Slovenia); Ostrikov, Kostya [Plasma Nanoscience Centre Australia (PNCA), CSIRO Materials Science and Engineering, P.O. Box 218, Lindfield, New South Wales 2070 (Australia); University of Sydney, Sydney, NSW 2006 (Australia)

2012-10-01T23:59:59.000Z

103

Energetic-Particle-Induced Geodesic Acoustic Mode Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA  

E-Print Network [OSTI]

Energetic-Particle-Induced Geodesic Acoustic Mode G. Y. Fu* Princeton Plasma Physics Laboratory-induced geodesic acoustic mode (EGAM) is shown to exist. The mode frequency and mode structure are determined comparable to that of geodesic acoustic mode (GAM) [4]. Here it is shown analytically and numerically

104

Magnetic Reconnection, a Key Self-Organization Process in Laboratory and Astrophysical Plasmas: Recent Research Progress  

Science Journals Connector (OSTI)

......reconnection observed in RFP plasma relaxation events,34) in spheromak merging experiments,32),33) or in solar flare evolution...discharges in other laboratory fusion devices such as the spheromak and the RFP (reversed-field-pinch), we observe similar......

Masaaki Yamada

2012-07-01T23:59:59.000Z

105

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

106

Stable relativistic/charge-displacement channels in ultrahigh power density (?1021 W/cm3) plasmas  

Science Journals Connector (OSTI)

...the contemporary production of vigorous thermonuclear environments, the achievable power density...acceleration, and the fast ignition of fusion targets. The key to the...Rhodes C K ( 1995 ) Plasma Phys Control Fusion 37 : 569 – 597 . 2 Borisov A B Borovskiy...

A. B. Borisov; J. W. Longworth; K. Boyer; C. K. Rhodes

1998-01-01T23:59:59.000Z

107

Absolute atomic oxygen density profiles in the discharge core of a microscale atmospheric pressure plasma jet  

Science Journals Connector (OSTI)

The micro atmospheric pressure plasma jet is an rf driven (13.56 MHz ? 20 ? W ) capacitively coupled discharge producing a homogeneous plasma at ambient pressure when fed with a gas flow of helium (1.4 slm) containing small admixtures of oxygen ( ? 0.5 % ) . The design provides excellent optical access to the plasma core. Ground state atomic oxygen densities up to 3 × 10 16 ? cm ? 3 are measured spatially resolved in the discharge core by absolutely calibrated two-photon absorption laser-induced fluorescence spectroscopy. The atomic oxygen density builds up over the first 8 mm of the discharge channel before saturating at a maximum level. The absolute value increases linearly with applied power.

Nikolas Knake; Kari Niemi; Stephan Reuter; Volker Schulz-von der Gathen; Jörg Winter

2008-01-01T23:59:59.000Z

108

Observations of small-scale plasma density depletions in arecibo HF heating experiments  

SciTech Connect (OSTI)

Observations of incoherent scattering of electromagnetic waves at UHF from Langmuir waves by a new scheme involving linear frequency modulation (chirping) of a UHF transmitter and the demodulation (dechirping) of the received signals have been applied during HF heating experiments. These observations show that the high power HF wave used for ionospheric modification creates small-scale plasma depletions instantly on a time scale of 5 ms. For a plasma frequency of 5.1 MHz, plasma frequency gradient of the order of 50 kHz/km, and power density input of the HF heater wave of 8.0 x 10/sup -5/ W/m/sup 2/ the depletion ranged from 3 to 5%. This appears to provide direct evidence that the HF-induced modifications involve Langmuir waves trapped in density cavities. copyrightAmerican Geophysical Union 1987

Isham, B.; Birkmayer, W.; Hagfors, T.; Kofman, W.

1987-05-01T23:59:59.000Z

109

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

110

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

111

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

SciTech Connect (OSTI)

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

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

2013-10-15T23:59:59.000Z

112

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

113

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

114

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

Science Journals Connector (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.

Ariel Márquez; José González; Ariel Tarifeño-Saldivia; Cristian Pavez; Leopoldo Soto; Alejandro Clausse

2012-01-01T23:59:59.000Z

115

Density profile in shock wave fronts of partially ionized xenon plasmas  

Science Journals Connector (OSTI)

Results for the reflection coefficient of shock-compressed dense xenon plasmas at pressures of 1.6–20 GPa and temperatures around 30 000 K are interpreted. In addition to former experiments using laser beams with ? = 1.06 µm, measurements at ? = 0.694 µm have been performed recently. Reflectivities typical for metallic systems are found at high densities. Besides free carriers, the theoretical description also takes into account the influence of the neutral component of the plasma on the reflectivity. A consistent description of the measured reflectivities is achieved only if a finite width of the shock wave front is considered.

H Reinholz; G Röpke; I Morozov; V Mintsev; Yu Zaparoghets; V Fortov; A Wierling

2003-01-01T23:59:59.000Z

116

The National Compact Stellarator Experiment at the Princeton Plasma Physics Laboratory  

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

Finding of No Significant Impact Finding of No Significant Impact Proposed National Compact Stellarator Experiment Princeton Plasma Physics Laboratory, New Jersey AGENCY: U.S. Department of Energy ACTION: Finding of No Significant Impact SUMMARY: The Department of Energy (DOE) has prepared an Environmental Assessment (EA), DOE/EA-1437, evaluating the environmental effects of the proposed fabrication, assembly and operation of a National Compact Stellarator Experiment (NCSX) within the existing C- Stellarator (CS) Building at C-Site of the Princeton Plasma Physics Laboratory (PPPL), Princeton, New Jersey. The purpose of the NCSX is to provide an experimental device to investigate the attractiveness of a compact stellarator as the basis for a fusion power reactor. Fusion energy has the potential to help compensate for dwindling supplies of fossil fuels, the

117

COHERENCE AND INTERMITTENCY OF ELECTRON DENSITY IN SMALL-SCALE  

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

OF ELECTRON DENSITY IN SMALL-SCALE INTERSTELLAR TURBULENCE P. W. Terry and K. W. Smith Center for Magnetic Self-Organization in Laboratory and Astrophysical Plasmas and...

118

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

E-Print Network [OSTI]

PLASMA PHYSICS LABORATORY PPPL PPPL-4114 PPPL-4114 #12;Princeton Plasma Physics Laboratory Report or subcontractors. PPPL Report Availability Princeton Plasma Physics Laboratory This report is posted on the U 2006. The home page for PPPL Reports and Publications is: http://www.pppl.gov/pub_report/ Office

119

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

120

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

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

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

122

Phase diagram for magnetic reconnection in heliophysical, astrophysical, and laboratory plasmas  

Science Journals Connector (OSTI)

Recent progress in understanding the physics of magnetic reconnection is conveniently summarized in terms of a phase diagram which organizes the essential dynamics for a wide variety of applications in heliophysics laboratory and astrophysics. The two key dimensionless parameters are the Lundquist number and the macrosopic system size in units of the ion sound gyroradius. In addition to the conventional single X-line collisional and collisionless phases multiple X-line reconnection phases arise due to the presence of the plasmoid instability either in collisional and collisionless current sheets. In particular there exists a unique phase termed “multiple X-line hybrid phase” where a hierarchy of collisional islands or plasmoids is terminated by a collisionless current sheet resulting in a rapid coupling between the macroscopic and kinetic scales and a mixture of collisional and collisionless dynamics. The new phases involving multiple X-lines and collisionless physics may be important for the emerging applications of magnetic reconnection to accelerate charged particles beyond their thermal speeds. A large number of heliophysical and astrophysical plasmas are surveyed and grouped in the phase diagram: Earth’s magnetosphere solar plasmas (chromosphere corona wind and tachocline) galactic plasmas (molecular clouds interstellar media accretion disks and their coronae Crab nebula Sgr A* gamma ray bursts and magnetars) and extragalactic plasmas (active galactic nuclei disks and their coronae galaxy clusters radio lobes and extragalactic jets). Significance of laboratory experiments including a next generation reconnectionexperiment is also discussed.

Hantao Ji; William Daughton

2011-01-01T23:59:59.000Z

123

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

124

Current initiation in low-density foam z-pinch plasmas  

Science Journals Connector (OSTI)

Low density agar and aerogel foams were tested as z-pinch loads on the Saturn accelerator to study current flow initiation. In these first experiments we studied the initial plasma conditions by measuring the visible emission at early times with a framing camera and a streaked one-dimensional imaging system. Later near the stagnation when the plasma is hotter x-ray imaging and spectraldiagnostics were used to characterize the plasma.Filamentation and arcing at the current contacts were observed. Bright implosion features were also observed. Increasing the early time conductivity by coating the target with a high-z layer and by providing a low-current prepulse is the most important factor in obtaining good coupling to the machine. None of the pinches were uniform along the z axis. The prime causes of these problems are believed to be the electrode contacts and the current return configuration. Solutions are discussed.

M. S. Derzon; T. J. Nash; G. O. Allshouse; A. J. Antolak; M. Hurst; J. S. McGurn; D. J. Muron; J. F. Seaman; J. MacFarlane; T. Demiris; L. Hrubesh; H. Lewis; D. Ryutov; T. Barber; T. Gilliland; D. Jobe; S. Lazier

1997-01-01T23:59:59.000Z

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

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

127

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

SciTech Connect (OSTI)

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

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

1994-07-01T23:59:59.000Z

128

Analysis of pulsed high-density HBr and Cl{sub 2} plasmas: Impact of the pulsing parameters on the radical densities  

SciTech Connect (OSTI)

The dynamic of charged particles in pulsed plasma is relatively well known since the 1990s. In contrast, works reporting on the impact of the plasma modulation frequency and duty cycle on the radicals' densities are scarce. In this work, we analyze the impact of these modulation parameters on the radicals' composition in Cl{sub 2} and HBr plasmas. The radicals' densities are measured by broad-band UV and vacuum-ultraviolet (VUV) absorption spectroscopy and modulated-beam mass spectrometry. We show that pulsing the rf power allows controlling the plasma chemistry and gives access to the plasma conditions that cannot be reached in continuous wave plasmas. In particular, we show that above 500 Hz, the pulsing frequency has no influence on the plasma chemistry, whereas in contrast the duty cycle is an excellent knob to control the fragmentation of the parent gas, thus the chemical reactivity of the discharge. At low duty cycle, a reduced gas fragmentation combined with a large ion flux leads to new etching conditions, compared to cw plasmas and the expected consequences on pulsed-etching processes are discussed.

Bodart, P.; Brihoum, M.; Cunge, G.; Joubert, O.; Sadeghi, N. [Laboratoire des Technologies de la Microelectronique, CNRS-LTM, 17 rue des Martyrs, Grenoble 38054 (France)

2011-12-01T23:59:59.000Z

129

Application of maximum likelihood methods to laser Thomson scattering measurements of low density plasmas  

SciTech Connect (OSTI)

Laser Thomson scattering (LTS) is an established plasma diagnostic technique that has seen recent application to low density plasmas. It is difficult to perform LTS measurements when the scattered signal is weak as a result of low electron number density, poor optical access to the plasma, or both. Photon counting methods are often implemented in order to perform measurements in these low signal conditions. However, photon counting measurements performed with photo-multiplier tubes are time consuming and multi-photon arrivals are incorrectly recorded. In order to overcome these shortcomings a new data analysis method based on maximum likelihood estimation was developed. The key feature of this new data processing method is the inclusion of non-arrival events in determining the scattered Thomson signal. Maximum likelihood estimation and its application to Thomson scattering at low signal levels is presented and application of the new processing method to LTS measurements performed in the plume of a 2-kW Hall-effect thruster is discussed.

Washeleski, Robert L.; Meyer, Edmond J. IV; King, Lyon B. [Michigan Technological University, Houghton, Michigan 49931 (United States)] [Michigan Technological University, Houghton, Michigan 49931 (United States)

2013-10-15T23:59:59.000Z

130

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

131

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

132

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

E-Print Network [OSTI]

.J. Kramer, E. Johnson, W. Solomon, and R. Nazikian October 2005 PRINCETON PLASMA PHYSICS LABORATORY PPPL PPPL-4113 PPPL-4113 #12;Princeton Plasma Physics Laboratory Report Disclaimers Full Legal Disclaimer or any agency thereof or its contractors or subcontractors. PPPL Report Availability Princeton Plasma

133

Spectroscopic study of a long high-electron-density argon plasma column generated at atmospheric pressure  

SciTech Connect (OSTI)

A stable plasma column is generated in a quartz tube using a pair of hollow electrodes driven by a sinusoidal power supply of 45 kHz at atmospheric pressure in argon. Two distinct operating modes (low-current and high-current modes) are identified through observing its discharge phenomena, measuring its electrical characteristics, and determining the gas temperatures by spectroscopic diagnosis of Q branch of UV OH spectrum. The electron density in the high-current mode is diagnosed by Stark broadening and is found to be two orders higher than that in low-current mode.

Li Shouzhe; Huang Wentong; Wang Dezhen [Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology), Ministry of Education, and School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116023 (China)

2010-02-15T23:59:59.000Z

134

Study of magnetic configuration effects on plasma boundary and measurement of edge electron density in the spherical tokamak compact plasma wall interaction experimental device using Li sheet beam  

SciTech Connect (OSTI)

Two-dimensional lithium beam imaging technique has been applied in the spherical tokamak CPD (compact plasma wall interaction experimental device) to study the effects of magnetic field configurations on rf plasma boundary in the absence of any plasma current, and also for the measurement of a two-dimensional edge electron density profile. With the present working condition of the diagnostics, the minimum measured electron density can be {approx}1.0x10{sup 16} m{sup -3}; this is considered to be the definition for the plasma boundary. The performance of the lithium sheet beam is absolutely calibrated using a quartz crystal monitor. Experimental results reveal that magnetic field configuration, either mirror or so-called null, critically affects the rf plasma boundary. A sharp lower boundary is found to exist in magnetic null configuration, which is quite different from that in the weak mirror configuration. Theoretical calculations of particle drift orbit and magnetic connection length (wall-to-wall) suggest that only mirror trapped particles are confined within a region where the magnetic connection length is {approx}4.0 m or more. A two-dimensional edge electron density profile is obtained from the observed Li I intensity profile. Overdense plasma formation is discussed from the viewpoint of mode conversion of rf wave into electron Bernstein wave and its dependence on the electron density profile.

Bhattacharyay, R.; Inada, Y.; Kikukawa, T.; Watanabe, S.; Sasaki, K.; Ryoukai, T. [Interdisciplinary Graduate School of Engineering Science, Kyushu University, Kasuga, Fukuoka 816 8580 (Japan); Zushi, H.; Hasegawa, M.; Hanada, K.; Sato, K. N.; Nakamura, K.; Sakamoto, M.; Idei, H.; Yoshinaga, T.; Kawasaki, S.; Nakashima, H.; Higashijima, A. [Research Institute of Applied Mechanics, Kyushu University, Kasuga, Fukuoka 816 8580 (Japan); Morisaki, T. [National Institute for Fusion Science, Toki 509 5292 (Japan)

2008-02-15T23:59:59.000Z

135

Study of magnetic configuration effects on plasma boundary and measurement of edge electron density in the spherical tokamak compact plasma wall interaction experimental device using Li sheet beam  

Science Journals Connector (OSTI)

Two-dimensional lithium beam imaging technique has been applied in the spherical tokamak CPD (compact plasma wall interaction experimental device) to study the effects of magnetic field configurations on rf plasma boundary in the absence of any plasma current and also for the measurement of a two-dimensional edge electron density profile. With the present working condition of the diagnostics the minimum measured electron density can be ? 1.0 × 10 16 m ? 3 ; this is considered to be the definition for the plasma boundary. The performance of the lithium sheet beam is absolutely calibrated using a quartz crystal monitor. Experimental results reveal that magnetic field configuration either mirror or so-called null critically affects the rf plasma boundary. A sharp lower boundary is found to exist in magnetic null configuration which is quite different from that in the weak mirror configuration. Theoretical calculations of particle drift orbit and magnetic connection length (wall-to-wall) suggest that only mirror trapped particles are confined within a region where the magnetic connection length is ? 4.0 m or more. A two-dimensional edge electron density profile is obtained from the observed Li I intensity profile. Overdense plasma formation is discussed from the viewpoint of mode conversion of rf wave into electron Bernstein wave and its dependence on the electron density profile.

R. Bhattacharyay; H. Zushi; T. Morisaki; Y. Inada; T. Kikukawa; S. Watanabe; K. Sasaki; T. Ryoukai; M. Hasegawa; K. Hanada; K. N. Sato; K. Nakamura; M. Sakamoto; H. Idei; T. Yoshinaga; S. Kawasaki; H. Nakashima; A. Higashijima

2008-01-01T23:59:59.000Z

136

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 Physics Laboratory Calculation of the Vacuum Green's Function Valid even for High Toroidal Mode Number Laboratory This report is posted on the U.S. Department of Energy's Princeton Plasma Physics Laboratory

137

Fast oscillatory behavior of the excited xenon density in the discharge cells of a plasma display panel  

SciTech Connect (OSTI)

Fast oscillation of the excited xenon density occurs universally after an electrical discharge in the cells of a plasma display panel. A theoretical model based on ion plasma oscillation simulates this oscillatory behavior of the excited xenon density reasonably well. The magnitude and lifetime of the excited xenon density in a metastable state depend highly on the electrode configuration. Particularly, T-type electrodes provide better generation and confinement of excited xenon atoms for an abundant emission of 173 nm ultraviolet light at a high level of efficiency.

Uhm, Han S. [Department of Molecular Science and Technology, Ajou University, Suwon 443-749 (Korea, Republic of); Choi, Eun H. [Department of Electrophysics, PDP Research Center, Kwangwoon University, Seoul 139-701 (Korea, Republic of)

2009-03-15T23:59:59.000Z

138

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

139

Sheath model for radio-frequency-biased, high-density plasmas valid for all ?/?i  

Science Journals Connector (OSTI)

A model is proposed for sheaths in high-density discharges, with radio-frequency (rf) bias applied at frequencies ? comparable to ?i, the ion plasma frequency at the edge of the sheath. The model treats ion dynamics using fluid equations, including all time-dependent terms. Model predictions for current, impedance, and power were compared to measurements performed in high-density discharges in argon at 1.33 Pa (10 mTorr) at rf bias frequencies from 0.1 to 10 MHz (?/?i from 0.006 to 1.8) and rf bias voltages from 1 to 200 V. Model predictions were in good agreement with measurements, much better than that obtained by models that neglect time-dependent ion dynamics. In particular, differences of as much as 40–50 % between power measurements and the power predicted by previous models are now explained and eliminated. The model also explains why methods of extracting plasma parameters from electrical measurements using previous sheath models may fail, and it suggests more accurate methods of extracting these parameters.

Mark A. Sobolewski

2000-12-01T23:59:59.000Z

140

Experimental test of models of high-plasma-density, radio-frequency sheaths  

Science Journals Connector (OSTI)

Measurements of the rf-bias current and voltage applied to the substrate electrode of a high-density plasma reactor, combined with dc measurements of the ion current at the electrode and capacitive probe measurements of the plasma potential, enabled a rigorous, quantitative test of models of the electrical properties of the sheath adjacent to the electrode. The measurements were performed for argon discharges at 1.33 Pa (10 mTorr), ion current densities of 1.3–13 mA/cm2, rf-bias frequencies of 0.1–10 MHz, and rf-bias voltages from less than 1 to more than 100 V. From the measurements, the current, voltage, impedance, and power of the sheath adjacent to the electrode were determined and were compared to model predictions. The properties of the opposing sheath, adjacent to grounded surfaces, were also determined. The behavior of the two sheaths ranged from nearly symmetric to very asymmetric. Changes in the symmetry are explained by models of the sheath impedance.

Mark A. Sobolewski

1999-01-01T23:59:59.000Z

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.


141

EVIDENCE FOR GENTLY SLOPING PLASMA DENSITY PROFILES IN THE DEEP CORONA: TYPE III OBSERVATIONS  

SciTech Connect (OSTI)

Type III radio bursts are produced near the local electron plasma frequency f{sub p} and near its harmonic 2f{sub p} by fast electrons ejected from the solar active regions and moving through the corona and solar wind. The coronal bursts have dynamic spectra with frequency rapidly falling with time, the typical duration being about 1-3 s. In the present paper, 37 well-defined coronal type III radio bursts (25-450 MHz) are analyzed. The results obtained substantiate an earlier statement that the dependence of the central frequency of the emission on time can be fitted to a power-law model, f(t) {proportional_to} (t - t{sub 0}){sup -{alpha}}, where {alpha} can be as low as 1. In the case of negligible plasma acceleration and conical flow, it means that the electron number density within about 1 solar radius above the photosphere will decrease as r {sup -2}, like in the solar wind. For the data set chosen, the index {alpha} varies in the range from 0.2 to 7 or bigger, with mean and median values of 1.2 and 0.5, respectively. A surprisingly large fraction of events, 84%, have {alpha} {<=} 1.2. These results provide strong evidence that in the type III source regions the electron number density scales as n(r) {proportional_to} (r - r{sub 0}){sup -{beta}}, with minimum, mean, and median {beta} = 2{alpha} of 0.4, 2.4, and 1.0, respectively. Hence, the typical density profiles are more gently sloping than those given by existing empirical coronal models. Several events are found with a wind-like dependence of burst frequency on time. Smaller power-law indices could result from the effects of non-conical geometry of the plasma flow tubes, deceleration of coronal plasma, and/or the curvature of the magnetic field lines. The last effect is shown to be too weak to explain such low power-law indices. A strong tendency is found for bursts from the same group to have similar power-law indices, thereby favoring the hypothesis that they are usually produced by the same source region.

Lobzin, V. V.; Cairns, I. H.; Robinson, P. A. [School of Physics, University of Sydney, NSW 2006 (Australia); Warmuth, A.; Mann, G. [Astrophysikalisches Institut Potsdam, D 14482 Potsdam (Germany); Gorgutsa, R. V.; Fomichev, V. V. [Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radiowave Propagation, 142190, Troitsk, Moscow Region (Russian Federation)

2010-12-01T23:59:59.000Z

142

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

143

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

144

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

145

Origin of protons accelerated by an intense laser and the dependence of their energy on the plasma density  

Science Journals Connector (OSTI)

We study the high-energy (1–4 MeV) proton production from a slab plasma irradiated by a ultrashort high-power laser. In our 2.5-dimensional particle-in-cell simulations, a p-polarized laser beam of 1.6×1019 W/cm2, 300 fs, ?L=1.053 ?m, illuminates a slab plasma normally; the slab plasma consists of a hydrogen plasma, and the target plasma thickness and the laser spot size are 2.5?L and 5?L, respectively. The simulation results show that an emitted proton energy depends on the slab plasma density, and three kinds of high-energy proton beams are generated at the target plasma surfaces: one kind of the proton beams is produced at the laser-illuminated target surface and accelerated to the same laser-incident side. The second is generated at the target surface opposite to the laser-illuminated target surface and is accelerated outward on the same side. The third is generated at the laser-illuminated target surface and accelerated to the opposite side while passing through the target plasma. The simulations also show a mechanism of proton accelerations. In an overdense plasma, laser energy goes to energies of hot electrons and magnetic fields in part; the electrons oscillate around the slab plasma so that a static electric field is generated and consequently protons are extracted. The magnetic field generated in the slab plasma exists longer and heats up the plasma electrons to sustain the static electric field even after the laser termination.

Takashi Nakamura and Shigeo Kawata

2003-02-06T23:59:59.000Z

146

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

147

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

148

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

149

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

E-Print Network [OSTI]

Prepared for the U.S. Department of Energy under Contract DE-AC02-09CH11466. Princeton Plasma Ernesto Mazzucato #12;Princeton Plasma Physics Laboratory Report Disclaimers Full Legal Disclaimer or any agency thereof or its contractors or subcontractors. PPPL Report Availability Princeton Plasma

Mazzucato, Ernesto

150

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

E-Print Network [OSTI]

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

Tillack, Mark

151

The effect of the driving frequency on the confinement of beam electrons and plasma density in low pressure capacitive discharges  

E-Print Network [OSTI]

The effect of changing the driving frequency on the plasma density and the electron dynamics in a capacitive radio-frequency argon plasma operated at low pressures of a few Pa is investigated by Particle in Cell/Monte Carlo Collisions simulations and analytical modeling. In contrast to previous assumptions the plasma density does not follow a quadratic dependence on the driving frequency in this non-local collisionless regime. Instead, a step-like increase at a distinct driving frequency is observed. Based on the analytical power balance model, in combination with a detailed analysis of the electron kinetics, the density jump is found to be caused by an electron heating mode transition from the classical $\\alpha$-mode into a low density resonant heating mode characterized by the generation of two energetic electron beams at each electrode per sheath expansion phase. These electron beams propagate through the bulk without collisions and interact with the opposing sheath. In the low density mode, the second bea...

Wilczek, S; Schulze, J; Schuengel, E; Brinkmann, R P; Derzsi, A; Korolov, I; Donkó, Z; Mussenbrock, T

2014-01-01T23:59:59.000Z

152

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

153

Viscosity and dilepton production of a chemically equilibrating quark-gluon plasma at finite baryon density  

E-Print Network [OSTI]

By considering the effect of shear viscosity we have investigated the evolution of a chemically equilibrating quark-gluon plasma at finite baryon density. Based on the evolution of the system we have performed a complete calculation for the dilepton production from the following processes: $q\\bar{q}{\\to}l\\bar{l}$, $q\\bar{q}{\\to}gl\\bar{l}$, Compton-like scattering ($qg{\\to}ql\\bar{l}$, $\\bar{q}g{\\to}{\\bar{q}}l\\bar{l}$), gluon fusion $g\\bar{g}{\\to}c\\bar{c}$, annihilation $q\\bar{q}{\\to}c\\bar{c}$ as well as the multiple scattering of quarks. We have found that quark-antiquark annihilation, Compton-like scatterring, gluon fusion, and multiple scattering of quarks give important contributions. Moreover, we have also found that the dilepton yield is an increasing function of the initial quark chemical potential, and the increase of the quark phase lifetime because of the viscosity also obviously raises the dilepton yield.

N. N. Guan; Z. J. He; J. L. Long; X. Z. Cai; Y. G. Ma; J. W. Li; W. Q. Shen

2009-09-02T23:59:59.000Z

154

The Effects of the Scattering by Edge Plasma Density Fluctuations on Lower Hyybrid Wave Propagation  

SciTech Connect (OSTI)

Scattering effects induced by edge density fluctuations on lower hybrid (LH) wave propagation are investigated. The scattering model used here is based on the work of Bonoli and Ott [Phys. Fluids 25 (1982) 361]. It utilizes an electromagnetic wave kinetic equation solved by a Monte Carlo technique. This scattering model has been implemented in GENRAY , a ray tracing code which explicitly simulates wave propagation, as well as collisionless and collisional damping processes, over the entire plasma discharge, including the scrape-off layer (SOL) that extends from the separatrix to the vessel wall. A numerical analysis of the LH wave trajectories and the power deposition profile with and without scattering is presented for Alcator CMod discharges. Comparisons between the measured hard x-ray emission on Alcator C-Mod and simulations of the data obtained from the synthetic diagnostic included in the GENRAY/CQL3D package are shown, with and without the combination of scattering and collisional damping. Implications of these results on LH current drive are discussed.

Bertelli, N; Bonoli, P T; Harvey, R W; Smirnov, A P; Baek, S G; Parker, R R; Phillips, C K; Valeo, E J; Wilson, J R

2012-08-27T23:59:59.000Z

155

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

E-Print Network [OSTI]

HEDP division at MIT performs cutting-edge research using laser-generated plasmas · Recent research

156

Nanometer scale linewidth control during etching of polysilicon gates in high-density plasmas  

Science Journals Connector (OSTI)

We address some of the plasma issues encountered for ultimate silicon gate patterning that should be fixed in order to establish the long term viability of plasma processes in integrated circuits manufacturing. For sub-100-nm gate dimensions, one of ... Keywords: CMOS scaling, critical dimension control, gate patterning, plasma etching

O. Joubert; E. Pargon; J. Foucher; X. Detter; G. Cunge; L. Vallier

2003-09-01T23:59:59.000Z

157

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

158

Helicity, Reconnection, and Dynamo Effects Princeton Plasma Physics Laboratory, Princeton University  

E-Print Network [OSTI]

]. As an elementary process in resistive plasmas, magnetic reconnection [Vasyliunas, 1975; Biskamp, 1993] has long a flux tube in a perfectly conducting plasma. Taylor [1974] conjectured that in a ``slightly''resistive focal point of research in electrically conductive fluids or plasmas attempting to explain the observed

159

Helicity, Reconnection, and Dynamo Eects Princeton Plasma Physics Laboratory, Princeton University  

E-Print Network [OSTI]

]. As an elementary process in resistive plasmas, magnetic reconnection [Vasyliunas, 1975; Biskamp, 1993] has long an invariantwithina ux tube ina perfectly conducting plasma. Taylor [1974] conjectured that in a \\slightly"resistive in electrically conductive uids or plasmas attempting to explain the observed solar and plane- tary magnetic #12

160

Visualizing electromagnetic fields in laser-produced counter-streaming plasma experiments for collisionless shock laboratory astrophysics  

SciTech Connect (OSTI)

Collisionless shocks are often observed in fast-moving astrophysical plasmas, formed by non-classical viscosity that is believed to originate from collective electromagnetic fields driven by kinetic plasma instabilities. However, the development of small-scale plasma processes into large-scale structures, such as a collisionless shock, is not well understood. It is also unknown to what extent collisionless shocks contain macroscopic fields with a long coherence length. For these reasons, it is valuable to explore collisionless shock formation, including the growth and self-organization of fields, in laboratory plasmas. The experimental results presented here show at a glance with proton imaging how macroscopic fields can emerge from a system of supersonic counter-streaming plasmas produced at the OMEGA EP laser. Interpretation of these results, plans for additional measurements, and the difficulty of achieving truly collisionless conditions are discussed. Future experiments at the National Ignition Facility are expected to create fully formed collisionless shocks in plasmas with no pre-imposed magnetic field.

Kugland, N. L.; Ross, J. S.; Glenzer, S. H.; Huntington, C.; Martinez, D.; Plechaty, C.; Remington, B. A.; Ryutov, D. D.; Park, H.-S. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94550 (United States)] [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94550 (United States); Chang, P.-Y.; Fiksel, G.; Froula, D. H. [Laboratory for Laser Energetics, University of Rochester, 250 E. River Road, Rochester, New York 14636 (United States)] [Laboratory for Laser Energetics, University of Rochester, 250 E. River Road, Rochester, New York 14636 (United States); Drake, R. P.; Grosskopf, M.; Kuranz, C. [Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, Ann Arbor, Michigan 48109 (United States)] [Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, Ann Arbor, Michigan 48109 (United States); Gregori, G.; Meinecke, J.; Reville, B. [Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU (United Kingdom)] [Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU (United Kingdom); Koenig, M.; Pelka, A. [Laboratoire pour l'Utilisation des Lasers Intenses (LULI), École Polytechnique-Univ, Paris VI, 91128 Palaiseau (France)] [Laboratoire pour l'Utilisation des Lasers Intenses (LULI), École Polytechnique-Univ, Paris VI, 91128 Palaiseau (France); and others

2013-05-15T23:59:59.000Z

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.


161

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

162

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

163

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

164

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

165

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

166

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

167

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

168

A laboratory plasma experiment for studying magnetic dynamics of accretion discs and jets  

Science Journals Connector (OSTI)

......also plasma detachment associated with spheromak formation, which may have relevance...This setup is commonly used to create spheromak plasmas (Rosenbluth Bussac 1979, Jarboe...the estimated V A. It is likely that a spheromak configuration is formed here; this was......

S. C. Hsu; P. M. Bellan

2002-08-01T23:59:59.000Z

169

Phase diagram for magnetic reconnection in heliophysical, astrophysical, and laboratory plasmas  

E-Print Network [OSTI]

, solar plasmas (chromosphere, corona, wind, and tachocline), galactic plasmas (molecular clouds are the Lundquist number and the macrosopic system size in units of the ion sound gyroradius. In addition, there exists a unique phase termed "multiple X-line hybrid phase" where a hierarchy of collisional islands

Ji, Hantao

170

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.

171

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

172

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

Office of Science (SC) Website

Directed Research and Development (LDRD) Management & Operating (M&O) Contracts Technology Transfer Work for Others Contact Information Laboratory Policy U.S. Department of Energy...

173

Plasma density ramp for relativistic self-focusing of an intense laser  

Science Journals Connector (OSTI)

It is known that a high-power laser propagating through an underdense plasma can acquire a minimum spot size due to relativistic self-focusing. Beyond the focus, the nonlinear...

Gupta, Devki N; Hur, Min S; Hwang, Ilmoon; Suk, Hyyong; Sharma, Ashok K

2007-01-01T23:59:59.000Z

174

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

175

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

176

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.

177

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

E-Print Network [OSTI]

Physics Laboratory PPPL- 4396PPPL-4396 Annual Site Environmental Report for Calendar Year 2004 March, 2009 or any agency thereof or its contractors or subcontractors. PPPL Report Availability Princeton Plasma Physics Laboratory: http://www.pppl.gov/techreports.cfm Office of Scientific and Technical Information

Princeton Plasma Physics Laboratory

178

Characteristics of ion-acoustic solitary wave in a laboratory dusty plasma under the influence of ion-beam  

SciTech Connect (OSTI)

We study the influence of ion beam and charged dust impurity on the propagation of dust ion-acoustic solitary wave in an unmagnetized plasma consisting of Boltzmann distributed electrons, positive ions, positive ion beam, and negatively charged immobile dusts in a double plasma device. On interacting with an ion beam, the solitary wave is bifurcated into a compressive fast and a rarefactive slow beam mode, and appears along with the primary wave. However, there exists a critical velocity of the beam beyond which the amplitude of the fast solitary wave starts diminishing and rarefactive slow beam mode propagates with growing amplitude. Whereas, the presence of charged dust impurity in the plasma reduces this critical beam velocity and a substantial modification in the phase velocity of the slow beam mode is observed with increasing dust density. Furthermore, the nonlinear wave velocity (Mach number) as well as the width of the compressive solitons are measured for different beam velocity and dust density, and are compared with those obtained from the K-dV equation. The experimental results are found in a well agreement with the theoretical predictions.

Deka, M. K.; Adhikary, N. C.; Bailung, H. [Physical Sciences Division, Institute of Advanced Study in Science and Technology, Vigyan Path, Paschim Boragaon, Garchuk, Guwahati 781035, Assam (India); Misra, A. P. [Department of Mathematics, Siksha Bhavana, Visva-Bharati University, Santiniketan 731 235 (India); Nakamura, Y. [Department of Physics, Faculty of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501 (Japan)

2012-10-15T23:59:59.000Z

179

Direct Detection of Resonant Electron Pitch Angle Scattering by Whistler Waves in a Laboratory Plasma  

E-Print Network [OSTI]

Direct Detection of Resonant Electron Pitch Angle Scattering by Whistler Waves in a Laboratory on the first laboratory experiment to directly detect resonant pitch angle scattering of energetic (ke or less, making it difficult to detect changes in electron pitch angle. A review of observations

California at Los Angles, University of

180

Identification of Y-Shaped and O-Shaped Diffusion Regions During Magnetic Reconnection in a Laboratory Plasma  

Science Journals Connector (OSTI)

Two strikingly different shapes of diffusion regions are identified during magnetic reconnection in a magnetohydrodynamic laboratory plasma. The shapes depend on the third vector component of the reconnecting magnetic fields. Without the third component (antiparallel or null-helicity reconnection), a thin double-Y–shaped diffusion region is identified. In this case, the neutral sheet current profile is accurately measured to be as narrow as the order of the ion gyro-radius. In the presence of an appreciable third component (cohelicity reconnection), an O-shaped diffusion region appears and grows into a spheromak configuration.

Masaaki Yamada; Hantao Ji; Scott Hsu; Troy Carter; Russell Kulsrud; Yasushi Ono; Francis Perkins

1997-04-21T23:59:59.000Z

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.


181

Quasi-monoenergetic Electron Beams from Laser-plasma Acceleration by Ionization-induced Injection in Low- density Pure Nitrogen  

E-Print Network [OSTI]

We report a laser wakefield acceleration of electron beams up to 130 MeV from laser-driven 4-mm long nitrogen gas jet. By using a moderate laser intensity (3.5*10^18 W.cm^(-2) ) and relatively low plasma densities (0.8*10^18 cm^(-3) to 2.7*10^18 cm^(-3)) we have achieved a stable regime for laser propagation and consequently a stable generation of electron beams. We experimentally studied the dependence of the drive laser energy on the laser-plasma channel and electron beam parameters. The quality of the generated electron beams is discussed within the framework of the ionization-induced injection mechanism.

Tao, Mengze; Li, Song; Mirzaie, Mohammad; Chen, Liming; He, Fei; Cheng, Ya; Zhang, Jie

2014-01-01T23:59:59.000Z

182

Observation of magnetic fluctuations and rapid density decay of magnetospheric plasma in Ring Trap 1  

SciTech Connect (OSTI)

The Ring Trap 1 device, a magnetospheric configuration generated by a levitated dipole field magnet, has created high-{beta} (local {beta} {approx} 70%) plasma by using electron cyclotron resonance heating (ECH). When a large population of energetic electrons is generated at low neutral gas pressure operation, high frequency magnetic fluctuations are observed. When the fluctuations are strongly excited, rapid loss of plasma was simultaneously observed especially in a quiet decay phase after the ECH microwave power is turned off. Although the plasma is confined in a strongly inhomogeneous dipole field configuration, the frequency spectra of the fluctuations have sharp frequency peaks, implying spatially localized sources of the fluctuations. The fluctuations are stabilized by decreasing the hot electron component below approximately 40%, realizing stable high-{beta} confinement.

Saitoh, H.; Yoshida, Z.; Morikawa, J.; Yano, Y.; Mikami, H.; Kasaoka, N.; Sakamoto, W. [Graduate School of Frontier Sciences, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561 (Japan)

2012-06-15T23:59:59.000Z

183

Secondary instability as cause of minor disruptions in density limit tokamak plasmas  

SciTech Connect (OSTI)

Experimental evidence was found in JET plasmas of a new instability at the onset of minor disruptions. This instability is observed during the growth of the well known m/n = 2/1 magnetic island and is localized close to it, behaving as a secondary instability to the island. The large heat fluxes towards the plasma edge, characteristic of minor disruptions, occur during the low rotation phase of the magnetic island at a time the amplitude of the secondary instability suffers a large increase. No poloidal or toroidal mode numbers could be assigned to the secondary instability.

Salzedas, F. [JET EFDA, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom); Eng. Phys. Department, Faculdade de Engenharia da Universidade do Porto, Rua Roberto Frias s/n, 4200-465 Porto (Portugal); Instituto de Plasmas e Fusao Nuclear, Association Euratom-IST, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); Collaboration: JET EFDA Contributors

2011-10-15T23:59:59.000Z

184

Amyloid protein SAA is an apoprotein of mouse plasma high density lipoprotein  

Science Journals Connector (OSTI)

...less cumbersome and more rapid method of thermal denaturation, which has been used to...6 M urea buffer were subjected to this thermal denaturation. Antigen solutions in the...migration (anode at bot- tom); stain, Sudan black B. plasma is illustrated in Fig...

E P Benditt; N Eriksen; R H Hanson

1979-01-01T23:59:59.000Z

185

A laboratory plasma experiment for studying magnetic dynamics of accretion discs and jets  

Science Journals Connector (OSTI)

......law, implies that an electric field E will be induced...component creates an electric potential drop V between...accretion disc, an electric potential V gun is applied...eight images per plasma discharge. The camera view is...b), the discrete arcs have expanded and begun......

S. C. Hsu; P. M. Bellan

2002-08-01T23:59:59.000Z

186

Scaling laws for collisionless laser-plasma interactions of relevance for laboratory astrophysics  

SciTech Connect (OSTI)

Scaling laws for interaction of ultra-intense laser beams with a collisionless plasmas are discussed. Special attention is paid to the problem of the collective ion acceleration. Symmetry arguments in application to the generation of the poloidal magnetic field are presented. A heuristic model for evaluating the magnetic field strength is proposed.

Ryutov, D D; Rermington, B A

2006-04-04T23:59:59.000Z

187

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

188

Direct photoetching of polymers using radiation of high energy density from a table-top extreme ultraviolet plasma source  

Science Journals Connector (OSTI)

In order to perform material interaction studies with intense extreme ultraviolet(EUV)radiation a Schwarzschild mirror objective coated with Mo/Si multilayers was adapted to a compact laser-driven EUV plasma source utilizing a solid Au target. By 10× demagnified imaging of the plasma a maximum pulse energy density of ? 0.73 ? J / cm 2 at a wavelength of 13.5 nm can be achieved in the image plane of the objective at a pulse duration of 8.8 ns. In this paper we present EUV photoetching rates measured for polymethyl methacrylate polycarbonate and polytetrafluoroethylene at various fluence levels. A linear dependence between etch depth and applied EUV pulse number could be observed without the necessity for any incubation pulses. By evaluating the slope of these data etch rates were determined revealing also a linear behavior for low fluences. A threshold energy density could not be observed. The slope of the linear etch regime as well as deviations from the linear trend at higher energy densities are discussed and compared to data known from deep UV laser ablation. Furthermore the surface roughness of the structuredpolymers was measured by atomic force microscopy and compared to the nonirradiated polymer surface indicating a rather smooth etch process (roughness increase of 20%–30%). The different shapes of the etch craters observed for the three polymers at high energy densities can be explained by the measured fluence dependence of the etch rates having consequences for the proper use of polymerablation for beam profiling of focused EUVradiation.

Frank Barkusky; Armin Bayer; Christian Peth; Klaus Mann

2009-01-01T23:59:59.000Z

189

Direct photoetching of polymers using radiation of high energy density from a table-top extreme ultraviolet plasma source  

SciTech Connect (OSTI)

In order to perform material interaction studies with intense extreme ultraviolet (EUV) radiation, a Schwarzschild mirror objective coated with Mo/Si multilayers was adapted to a compact laser-driven EUV plasma source utilizing a solid Au target. By 10x demagnified imaging of the plasma a maximum pulse energy density of {approx}0.73 J/cm{sup 2} at a wavelength of 13.5 nm can be achieved in the image plane of the objective at a pulse duration of 8.8 ns. In this paper we present EUV photoetching rates measured for polymethyl methacrylate, polycarbonate, and polytetrafluoroethylene at various fluence levels. A linear dependence between etch depth and applied EUV pulse number could be observed without the necessity for any incubation pulses. By evaluating the slope of these data, etch rates were determined, revealing also a linear behavior for low fluences. A threshold energy density could not be observed. The slope of the linear etch regime as well as deviations from the linear trend at higher energy densities are discussed and compared to data known from deep UV laser ablation. Furthermore, the surface roughness of the structured polymers was measured by atomic force microscopy and compared to the nonirradiated polymer surface, indicating a rather smooth etch process (roughness increase of 20%-30%). The different shapes of the etch craters observed for the three polymers at high energy densities can be explained by the measured fluence dependence of the etch rates, having consequences for the proper use of polymer ablation for beam profiling of focused EUV radiation.

Barkusky, Frank; Bayer, Armin; Peth, Christian; Mann, Klaus [Laser-Laboratorium-Goettingen e.V., Hans-Adolf-Krebs-Weg 1, D-37077 Goettingen (Germany)

2009-01-01T23:59:59.000Z

190

Investigating the Dynamics and Density Evolution of Returning Plasma Blobs from the 2011 June 7 Eruption  

E-Print Network [OSTI]

This work examines infalling matter following an enormous Coronal Mass Ejection (CME) on 2011 June 7. The material formed discrete concentrations, or blobs, in the corona and fell back to the surface, appearing as dark clouds against the bright corona. In this work we examined the density and dynamic evolution of these blobs in order to formally assess the intriguing morphology displayed throughout their descent. The blobs were studied in five wavelengths (94, 131, 171, 193 and 211 \\AA) using the Solar Dynamics Observatory Atmospheric Imaging Assembly (SDO/AIA), comparing background emission to attenuated emission as a function of wavelength to calculate column densities across the descent of four separate blobs. We found the material to have a column density of hydrogen of approximately 2 $\\times$ 10$^{19}$ cm$^{-2}$, which is comparable with typical pre-eruption filament column densities. Repeated splitting of the returning material is seen in a manner consistent with the Rayleigh-Taylor instability. Furthe...

Carlyle, Jack; van Driel-Gesztelyi, Lidia; Innes, Davina; Hillier, Andrew; Matthews, Sarah

2014-01-01T23:59:59.000Z

191

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

E-Print Network [OSTI]

CA, 94551, USA Princeton Plasma Physics Laboratory,Laboratory, and Princeton Plasma Physics Laboratory (theEng-48, and by the Princeton Plasma Physics Laboratory under

Logan, B.G.

2007-01-01T23:59:59.000Z

192

Electron density measurements of atmospheric-pressure non-thermal N2 plasma jet by Stark broadening and irradiance intensity methods  

Science Journals Connector (OSTI)

An atmospheric-pressure non-thermal plasma jet excited by high frequency alternating current using nitrogen is developed and the electron density in the active region of this plasma jet is investigated by two different methods using optical emission spectroscopy Stark broadening and irradiance intensity method. The irradiance intensity method shows that the average electron density is about 1020/m3 which is slightly smaller than that by the Stark broadening method. However the trend of the change in the electron density with input power obtained by these two methods is consistent.

2014-01-01T23:59:59.000Z

193

Radial excitation temperatures and electron number densities in a 9, 27 and 50 \\{MHz\\} inductively-coupled argon plasma  

Science Journals Connector (OSTI)

This work is the result of experiments performed on a 9, 27 and 50 \\{MHz\\} atmospheric pressure argon ICP uing the same thermometric species and instrumentation. Radiation originating from plasma volume with 0.25 mm2 projected areas were measured. The lateral observed spatially integrated radiances were transformed to radial functions by using Abel integral equations. Variations of radiances from Ca atom and ion transitions as function of observation height were studied. Two ion transitions of Ca with sufficient excitation energy difference were chosen for two-line temperature determinations, while substitution of atom to ion radiance ratios into the Saha equation were used in calculating values for the electron number density. The cooling effect of the central penetrating nebulizer gas on the plasma centres was clearly observed through a decrease in the excitation temperatures at the lowest observation heights above the r.f. coils. Experimental evidence indicates a general decrease in excitation temperature with increasing generator frequency. The same tendency was observed for the electron number density. These phenomena are probably due to the variation in skin depth at the different frequencies.

W.H. Gunter; K. Visser; P.B. Zeeman

1983-01-01T23:59:59.000Z

194

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

195

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

196

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

197

Hard TiCx/SiC/a-C:H nanocomposite thin films using pulsed high energy density plasma focus device  

Science Journals Connector (OSTI)

Abstract Thin films of TiCx/SiC/a-C:H were synthesized on Si substrates using a complex mix of high energy density plasmas and instability accelerated energetic ions of filling gas species, emanated from hot and dense pinched plasma column, in dense plasma focus device. The conventional hollow copper anode of Mather type plasma focus device was replaced by solid titanium anode for synthesis of TiCx/SiC/a-C:H nanocomposite thin films using CH4:Ar admixture of (1:9, 3:7 and 5:5) for fixed 20 focus shots as well as with different number of focus shots with fixed CH4:Ar admixture ratio 3:7. XRD results showed the formation of crystalline TiCx/SiC phases for thin film synthesized using different number of focus shots with CH4:Ar admixture ratio fixed at 3:7. SEM results showed that the synthesized thin films consist of nanoparticle agglomerates and the size of agglomerates depended on the CH4:Ar admixture ratio as well as on the number of focus shots. Raman analysis showed the formation of polycrystalline/amorphous Si, SiC and a-C for different CH4:Ar ratio as well as for different number of focus shots. The XPS analysis confirmed the formation of TiCx/SiC/a-C:H composite thin film. Nanoindentation results showed that the hardness and elastic modulus values of composite thin films increased with increasing number of focus shots. Maximum values of hardness and elastic modulus at the surface of the composite thin film were found to be about 22 and 305 GPa, respectively for 30 focus shots confirming the successful synthesis of hard composite TiCx/SiC/a-C:H coatings.

Z.A. Umar; R.S. Rawat; K.S. Tan; A.K. Kumar; R. Ahmad; T. Hussain; C. Kloc; Z. Chen; L. Shen; Z. Zhang

2013-01-01T23:59:59.000Z

198

FY 2006 SC Laboratory Performance Report Cards | U.S. DOE Office...  

Office of Science (SC) Website

National Laboratory Oak Ridge National Laboratory Pacific Northwest National Laboratory Princeton Plasma Physics Laboratory SLAC National Accelerator Laboratory Thomas Jefferson...

199

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

200

Stable relativistic/charge-displacement channels in ultrahigh power density (?1021 W/cm3) plasmas  

Science Journals Connector (OSTI)

...mankind with an origin that predates the Stone Age. From the use of a wooden club to the contemporary production of vigorous thermonuclear environments, the achievable power density (W/cm 3 ) has been advanced by approximately a factor of 20 orders of magnitude...

A. B. Borisov; J. W. Longworth; K. Boyer; C. K. Rhodes

1998-01-01T23:59:59.000Z

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.


201

US Heavy Ion Beam Research for Energy Density Physics Applications and Fusion  

E-Print Network [OSTI]

Laboratory, USA Princeton Plasma Physics Laboratory,Eng-48, and by the Princeton Plasma Physics Laboratory under

2005-01-01T23:59:59.000Z

202

Develpoment of a one-meter plasma source for heavy ion beam charge neutralization  

E-Print Network [OSTI]

was constructed at the Princeton Plasma Physics Laboratory (C. Davidson Plasma Physics Laboratory Princeton University,

2005-01-01T23:59:59.000Z

203

Contrib. Plasma Phys. 49, No. 1, 76 89 (2009) / DOI 10.1002/ctpp.200910011 Electric Microfield Distributions in Li+  

E-Print Network [OSTI]

widely applied in plasma diagnostics to evaluate plasma densities in stellar atmosphere or in laboratoryContrib. Plasma Phys. 49, No. 1, 76 ­ 89 (2009) / DOI 10.1002/ctpp.200910011 Electric Microfield Distributions in Li+ Plasma With Account of the Ion Structure S. Sadykova1 , W. Ebeling1 , I. Valuev2 , and I

Ebeling, Werner

204

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

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

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

207

Resonant and Nonresonant Electron Cyclotron Heating at Densities above the Plasma Cutoff by O-X-B Mode Conversion at the W7-As Stellarator  

Science Journals Connector (OSTI)

The extension of the experimentally accessible plasma densities with electron cyclotron heating beyond the plasma cutoff density and the removal of the restriction to a resonant magnetic field, both via mode conversion heating from an O-wave to an X-wave and, finally, to an electron Bernstein (O-X-B) wave, was investigated and successfully demonstrated at the W7-AS stellarator. In addition to the heating effect, clear evidence for both mode conversion steps was detected for the first time.

H. P. Laqua; V. Erckmann; H. J. Hartfuß; H. Laqua; W7-AS Team ECRH Group

1997-05-05T23:59:59.000Z

208

High Core Electron Confinement Regimes in FTU Plasmas with Low- or Reversed-Magnetic Shear and High Power Density Electron-Cyclotron-Resonance Heating  

Science Journals Connector (OSTI)

Electron temperatures in excess of 8 keV have been obtained by electron-cyclotron-resonance heating on FTU plasmas at peak densities up to 8×1019 m -3. The magnetic shear in the plasma core is low or negative, and the electron heat diffusivity remains at, or below, the Ohmic level (0.2 m 2/s), in spite of the very large heating power density (10–20 MW/m 3) which produces extremely high temperature gradients (up to 120 keV/m). The ion heat transport remains at the neoclassical level.

P. Buratti et al.

1999-01-18T23:59:59.000Z

209

Recent U.S. advances in ion-beam-driven high energy density physics and heavy ion fusion  

E-Print Network [OSTI]

Sefkow, E.A. Startsev Princeton Plasma Physics Laboratory,Eng-48, and by the Princeton Plasma Physics Laboratory underLaboratory, and Princeton Plasma Physics Laboratory (the

2006-01-01T23:59:59.000Z

210

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

E-Print Network [OSTI]

2002 and 2003 Prepared by: Virgina L. Finley December 2004 PRINCETON PLASMA PHYSICS LABORATORY PPPL PPPL-4039 PPPL-4039 #12;PPPL Report Disclaimers Full Legal Disclaimer This report was prepared agency thereof or its contractors or subcontractors. PPPL Report Availability This report is posted

Princeton Plasma Physics Laboratory

211

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]

Very 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 a load of 50 g, the coefficient of friction falls to -0.001. This clearly shows the effectiveness

Tzeng, Yonhua

212

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

SciTech Connect (OSTI)

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

Cairns, I. H.; Lobzin, V. V.; Li, B.; Robinson, P. A. [School of Physics, University of Sydney, NSW 2006 (Australia); Warmuth, A.; Mann, G. [Astrophysikalisches Institut Potsdam, D 14482 Potsdam (Germany)

2009-12-01T23:59:59.000Z

213

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

214

Two-dimensional laser-induced fluorescence imaging of metastable density in low-pressure radio frequency argon plasmas with added O2, Cl2,  

E-Print Network [OSTI]

frequency argon plasmas with added O2, Cl2, and CF4 Brian K. McMillina) and M. R. Zachariah Chemical Science, and CF4 on the argon metastable relative density and spatial distribution in low-pressure, radio at the powered electrode. In contrast, the addition of either Cl2 or CF4 was found to significantly modify

Zachariah, Michael R.

215

Two-dimensional imaging of CF2 density by laser-induced fluorescence in CF4 etching plasmas in the gaseous electronics conference  

E-Print Network [OSTI]

frequency argon plasmas with added O2, Cl2, and CF4 Brian K. McMillina) and M. R. Zachariah Chemical Science, and CF4 on the argon metastable relative density and spatial distribution in low-pressure, radio at the powered electrode. In contrast, the addition of either Cl2 or CF4 was found to significantly modify

Zachariah, Michael R.

216

Photoresist Trimming in Oxygen-Based High-Density Plasmas:? Effect of HBr and Cl2 Addition to CF4/O2 Mixtures  

Science Journals Connector (OSTI)

Cl2/CF4/O2c ... using NF3, CF4, SiF4, Cl2, HBr, and He/O2. ... Resist trimming in high-density CF4/O2 plasmas for sub-0.1 ?m device fabrication ...

Chian-Yuh Sin; Bing-Hung Chen; W. L. Loh; J. Yu; P. Yelehanka; A. See; L. Chan

2003-10-23T23:59:59.000Z

217

Behaviour and stability of Trivelpiece-Gould modes in non-neutral plasma containing small density fraction of background gas ions  

SciTech Connect (OSTI)

It is shown that the frequencies of Trivelpiece-Gould (TG) modes in non-neutral plasma can get into the low-frequency range due to the Doppler shift caused by plasma rotation in crossed fields. TG modes interact with the ion modes that leads to plasma instability. In paper the frequency spectrum of 'cold' electron plasma completely filling a waveguide and containing small density fraction of ions of background gas is determined numerically. For ions the kinetic description is used. Oscillations having azimuthal number m= 2 are considered. In this case both low- and upper-hybrid TG modes get into the low-frequency range. The spectrum consists of families of 'modified' ion cyclotron (MIC) modes and electron TG modes with the frequencies equal to hybrid frequencies with the Doppler shift. The growth rates of upper-hybrid modes are much faster than the growth rates of low-hybrid and MIC modes.

Yeliseyev, Y. N. [Institute of Plasma Physics, National Science Center Kharkov Institute of Physics and Technology, Akademicheskaya St., 1, 61108 Kharkov (Ukraine)

2013-03-19T23:59:59.000Z

218

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

219

Density sensitivity of intrinsic rotation profiles in ion cyclotron range of frequency-heated L-mode plasmas  

E-Print Network [OSTI]

The physical mechanisms that cause tokamak plasmas to rotate toroidally without external momentum input are of considerable interest to the plasma physics community. This paper documents a substantial change in both the ...

Reinke, Matthew Logan

220

A Space-Charge-Neutralizing Plasma for Beam Drift Compression  

E-Print Network [OSTI]

76CH-O3073 with the Princeton Plasma Physics Laboratory.CA 94720, USA ^Princeton Plasma Physics Laboratory,

Roy, P.K.

2008-01-01T23:59:59.000Z

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.


221

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

222

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

223

Superradiant pulse compression using freecarrier plasma G. Shvets and N. J. Fisch, Princeton University, Plasma Physics Laboratory, Princeton, NJ 08543, tel. (609)  

E-Print Network [OSTI]

medium for parametric conversion of the energy of a long higher­frequency laser beam into the energy in this paper, utilizes the free­electron plasma as a nonlinear medium for parametric conversion of the energySuperradiant pulse compression using free­carrier plasma G. Shvets and N. J. Fisch, Princeton

224

2034 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 36, NO. 5, OCTOBER 2008 Simulations of a Miniaturized Cylindrical  

E-Print Network [OSTI]

are with the Princeton Plasma Physics Laboratory, Princeton University, Princeton, NJ 08543 USA (e-mail: yraitses2034 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 36, NO. 5, OCTOBER 2008 Simulations, respectively. n, n0, ne, and ni Plasma, reference, electron, and ion densities, respectively. N Neutral gas

225

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

226

Approximate analytical solutions for continuously focused beams and single-species plasmas in thermal equilibrium  

E-Print Network [OSTI]

of Energy at Princeton Plasma Phys- ics Laboratory underand Steven M. Lund 2,b) Princeton Plasma Physics Laboratory,1Princeton Plasma Physics Laboratory, Princeton, New Jersey

Heimbucher, Lynn

2009-01-01T23:59:59.000Z

227

Survey of Collective Instabilities and Beam-Plasma Interactions in Intense Heavy Ion Beams  

E-Print Network [OSTI]

Background Plasma”, Princeton Plasma Physics Laboratoryand Edward A. Startsev Princeton Plasma Physics Laboratory,and Edward A. Startsev Princeton Plasma Physics Laboratory,

Davidson, Ronald C.

2009-01-01T23:59:59.000Z

228

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

229

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

230

3-D particle-in-cell simulations for quasi-phase matched direct laser electron acceleration in density-modulated plasma waveguides  

E-Print Network [OSTI]

Quasi-phase matched direct laser acceleration (DLA) of electrons can be realized with guided, radially polarized laser pulses in density-modulated plasma waveguides. A 3-D particle-in-cell model has been developed to describe the interactions among the laser field, injected electrons, and the background plasma in the DLA process. Simulations have been conducted to study the scheme in which seed electron bunches with moderate energies are injected into a plasma waveguide and the DLA is performed by use of relatively low-power (0.5-2 TW) laser pulses. Selected bunch injection delays with respect to the laser pulse, bunch lengths, and bunch transverse sizes have been studied in a series of simulations of DLA in a plasma waveguide. The results show that the injection delay is important for controlling the final transverse properties of short electron bunches, but it also affects the final energy gain. With a long injected bunch length, the enhanced ion-focusing force helps to collimate the electrons and a relativ...

Lin, M -W; Chen, S -H; Jovanovic, I

2014-01-01T23:59:59.000Z

231

Science Education Lab | Princeton Plasma Physics Lab  

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

Lab Lab Science Education Laboratory Overview Gallery: (Photo by Remote Control Glow Discharge) (Photo by DC Glow Discharges for Undergraduate Laboratories) (Photo by Atmospheric Plasma Laboratory) (Photo by 3D Printing Laboratory) (Photo by Remote Control Glow Discharge) (Photo by Plasma Speaker with 200 Hz input) (Photo by Dusty Plasma Laboratory) The Science Education Laboratory is a fusion (pun intended) of research between education and plasma science. This unique facility includes a teaching laboratory/classroom, two research labs, and student offices/storage/prep room. The research performed in the Science Education Laboratory is currently centered upon dusty plasmas, plasma speakers, remote control of plasmas for educational purposes, atmospheric plasmas and

232

Annual Report Alfvn Laboratory  

E-Print Network [OSTI]

discharge type for atmospheric plasma processing 97 C.2.5 Diagnostics of a pulsed RF-plasma 98 C.2 LABORATORY 3 2.1 Plasma Physics 5 2.2 Fusion Plasma Physics 6 2.3 Applied Electrophysics 7 2.3.1 Accelerator of Plasma Physics Section page A.1 Space physics group research 33 A.1.1 Rocket experiments 34 A.1

Haviland, David

233

COMPUTER SIMULATION OF THE UMER ELECTRON GUN* I. Haber, Plasma Physics Division, Naval Research Laboratory, Washington, DC 20375  

E-Print Network [OSTI]

COMPUTER SIMULATION OF THE UMER ELECTRON GUN* I. Haber, Plasma Physics Division, Naval Research conducted with the aim of understanding the space-charge-dominated physics in the gun and injector transport is on simulating the beam propagation in the gun region between the cathode grid and the anode grid for comparison

Valfells, Ágúst

234

* 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

235

Experimental study of two-fluid effects on magnetic reconnection in a laboratory plasma with variable collisionality  

E-Print Network [OSTI]

magneto- hydrodynamics MHD , magnetic field lines are strongly fro- zen into and move together region and move away. In the MHD formulation, the motion of magnetic field lines in a plasma can =0, Eq. 2 states that magnetic field lines move with the fluid as elaborately discussed by Parker.1

236

Calculation of the Electron Velocity Distribution Function in a Plasma Slab with Large Temperature and Density Gradients  

Science Journals Connector (OSTI)

...velocity. The distribution function for the...calculate the distribution function as a...region of the quiet Sun using several data-sets for temperature and density gradients...high-velocity tail of the distribution function. The...

1990-01-01T23:59:59.000Z

237

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

238

ITER | Princeton Plasma Physics Lab  

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

pioneering plasma physicist whose contributions to the U.S. Department of Energy's (DOE) Princeton Plasma Physics Laboratory (PPPL) ranged from seminal advances in fusion energy...

239

Stellarators | Princeton Plasma Physics Lab  

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

in stellarators By John Greenwald Researchers at the U.S. Department of Energy's Princeton Plasma Physics Laboratory (PPPL) and the Max Planck Institute of Plasma Physics...

240

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

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

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

242

Purpose | Princeton Plasma Physics Lab  

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

Our goal is to support as many projects as possible. As a DOE National Laboratory, the Princeton Plasma Physics Laboratory maintains an experienced staff of scientists,...

243

STEM | Princeton Plasma Physics Lab  

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

glimpse at the cutting edge research taking place at the U.S. Department of Energy's Princeton Plasma Physics Laboratory when the Laboratory, which already offers tours to...

244

Education | Princeton Plasma Physics Lab  

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

glimpse at the cutting edge research taking place at the U.S. Department of Energy's Princeton Plasma Physics Laboratory when the Laboratory, which already offers tours to...

245

Sandia National Laboratories: Z Pulsed Power Facility: Publications  

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

Publications Publications *only first authors listed 2013 Author Title Journal Volume RE Falcon An experimental platform for creating white dwarf photospheres in the laboratory High Energy Density Physics 9 TA Haill Mesoscale simulation of mixed equations of state with application to shocked platinum-doped PMP foams Procedia Engineering 58 SB Hansen Testing the reliability of Non-LTE Spectroscopic Models for Complex Ions High Energy Density Physics 9 B Jones Basis set expansion for inverse problems in plasma diagnostic analysis Review of Scientific Instruments 84 PF Knapp Diagnosing suprathermal ion populations in Z-pinch plasmas using fusion neutron spectra Physics of Plasmas 20 MD Knudson Shock response of low-density silica aerogel in the multi-Mbar regime Journal of Applied Physics

246

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

247

Complex-plasma boundaries  

Science Journals Connector (OSTI)

This study deals with the boundary between a normal plasma of ions and electrons, and an adjacent complex plasma of ions, electrons, and microparticles, as found in innumerable examples in nature. Here we show that the matching between the two plasmas involve electrostatic double layers. These double layers explain the sharp boundaries observed in the laboratory and in astrophysics. A modified theory is derived for the double layers that form at the discontinuity between two different complex plasmas and at the point of contact of three complex plasmas. The theory is applied to the first measurements from the Plasma Kristall Experiment (PKE) Nefedov Laboratory in the International Space Station.

B. M. Annaratone; S. A. Khrapak; P. Bryant; G. E. Morfill; H. Rothermel; H. M. Thomas; M. Zuzic; V. E. Fortov; V. I. Molotkov; A. P. Nefedov; S. Krikalev; Yu. P. Semenov

2002-11-26T23:59:59.000Z

248

Laboratories | U.S. DOE Office of Science (SC)  

Office of Science (SC) Website

Laboratories Laboratories Laboratories Ames Laboratory Argonne National Laboratory Brookhaven National Laboratory Fermi National Accelerator Laboratory Lawrence Berkeley National Laboratory Oak Ridge National Laboratory Pacific Northwest National Laboratory Princeton Plasma Physics Laboratory SLAC National Accelerator Laboratory Thomas Jefferson National Accelerator Facility Laboratory Policy and Evaluation Safety, Security and Infrastructure Laboratory Science Highlights Contact Information Office of Science U.S. Department of Energy 1000 Independence Ave., SW Washington, DC 20585 P: (202) 586-5430 Ames Laboratory Ames Laboratory Argonne Argonne National Laboratory BNL NSLS II Brookhaven National Laboratory Fermilab Wilson Hall Fermi National Accelerator Laboratory Lawrence Berkeley National Laboratory

249

Laboratories to Explore, Explain VLBACHANDRA  

E-Print Network [OSTI]

Institute of Technology Idaho National Engineering Laboratory Lawrence Livermore National Laboratory, at least, be one that allows the scientific exploration of burning plasmas" and if Japan and Europe do

250

Integration of Microsoft Windows applications with \\{MDSplus\\} data acquisition on the National Spherical Torus Experiment at the Princeton Plasma Physics Laboratory  

Science Journals Connector (OSTI)

Data acquisition on the National Spherical Torus Experiment at the Princeton Plasma Physics Laboratory (PPPL) has increasingly involved the use of Personal Computers and specially developed ‘turn-key’ hardware and software systems to control diagnostics. Interaction with these proprietary software packages is accomplished through use of Visual Basic, or Visual C++ and Component Object Model (com) technology. com is a software architecture that allows the components made by different software vendors to be combined into a variety of applications. This technology is particularly well suited to these systems because of its programming language independence, standards for function calling between components, and ability to transparently reference remote processes. com objects make possible the creation of acquisition software that can control the experimental parameters of both the hardware and software. Synchronization of these applications for diagnostics, such as charged couple device cameras and residual gas analyzers, with the rest of the experiment event cycle at PPPL has been made possible by utilization of the \\{MDSplus\\} libraries for Windows. Instead of transferring large data files to remote disk space, Windows \\{MDSplus\\} events and I/O functions allow us to put raw data into \\{MDSplus\\} directly from interactive data language for Windows and Visual Basic. The combination of com technology and the \\{MDSplus\\} libraries for Windows provide the tools for many new possibilities in versatile acquisition applications and future diagnostics.

Dana M. Mastrovito

2002-01-01T23:59:59.000Z

251

Measurement of electron densities by a microwave cavity method in 13.56-MHz RF plasmas of Ar, CF4, C2F6, and CHF3  

Science Journals Connector (OSTI)

Electron densit ies have been determined /or RF plasmas that were generated within a microwave resonant cavity by measuring the difference of the resonance frequencies with and without plasma. Since that metho...

M. Haverlag; G. M. W. Kroesen; T. H. J. Bisschops…

1991-09-01T23:59:59.000Z

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

Microwave plasma conversion of volatile organic compounds  

E-Print Network [OSTI]

MHz; Gerling Laboratory) and a resonant plasma tuner (ASTEX) were used to generate an argon/steam- based plasma at one atmosphere

Ko, Y; Yang, G S; Chang, DPY; Kennedy, Ian M

2003-01-01T23:59:59.000Z

254

IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL.  

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

of phenomena both in laboratory plasmas, like those magnetically confined in thermonuclear fusion exper- iments 1, and in several natural plasma systems, like for example...

255

International collaborations | Princeton Plasma Physics Lab  

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

in stellarators By John Greenwald Researchers at the U.S. Department of Energy's Princeton Plasma Physics Laboratory (PPPL) and the Max Planck Institute of Plasma Physics...

256

Procurement Division Introduction | Princeton Plasma Physics...  

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

Technology Transfer Furth Plasma Physics Library Procurement Division Introduction The Princeton Plasma Physics Laboratory (PPPL) is operated by Princeton University under...

257

Press Releases Archive | Princeton Plasma Physics Lab  

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

Plasma Physics Laboratory (PPPL) and the Max Planck Institute of Plasma Physics in Germany have devised a new method for minimizing turbulence in bumpy donut-shaped...

258

Particle beam dynamics | Princeton Plasma Physics Lab  

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

Particle beam dynamics Particle beam dynamics Subscribe to RSS - Particle beam dynamics The study of the physics of charged particle beams and the accelerators that produce them. This cross-disciplinary area intersects with fields such as plasma physics, high-energy density science, and ultra-fast lasers. Premiere issue of "Quest" magazine details PPPL's strides toward fusion energy and advances in plasma science Quest Magazine Summer 2013 Welcome to the premiere issue of Quest, the annual magazine of the U.S. Department of Energy's Princeton Plasma Physics Laboratory (PPPL). Read more about Premiere issue of "Quest" magazine details PPPL's strides toward fusion energy and advances in plasma science Ronald C Davidson Ronald Davidson heads PPPL research on charged particle beam dynamics and

259

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

260

High-Fidelity Simulation of Tokamak Edge Plasma Transport | Argonne...  

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

Plasma density fluctuation from large amplitude nonlinear turbulence in the tokamak edge region, obtained from the gyrokinetic code XGC1 Plasma density fluctuation from large...

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

Princeton University Plasma Physics Laboratory  

E-Print Network [OSTI]

Issued August 1995 #12;-2- NON-SEQUENTIAL LIST PPPL-2848 Withdrawn PPPL-2864 Anomalous Delayed Loss: Darrow, D.S., Fredrickson, E.D., Mynick, H.E. PPPL-2867 Reduced Optical Transmission of SiO2 Fibers.W. PPPL-2868 Ion Cyclotron Transmisstion Spectroscopy in the Greene, G.J. 53 pgs. Tokamak Fusion Test

262

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

263

Plasma Physics John F. Kennedy  

E-Print Network [OSTI]

v v v v v Princeton Plasma Physics Laboratory N 278 95 1 95 18 NEW YORK John F. Kennedy Int Campus/ Sayre Drive Sign PPPLSayre Dr. Location: Princeton Plasma Physics Laboratory James Forrestal Campus U.S. Route #1 North at Sayre Drive Plainsboro, NJ 08536 Mailing Address: Princeton Plasma Physics

Princeton Plasma Physics Laboratory

264

Harry E Mynick | Princeton Plasma Physics Lab  

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

Laboratory. Dr. Mynick is a Principal Research Physicist in the Theory Department at the Princeton Plasma Physics Laboratory (PPPL). Mynick is the author of more than 120...

265

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

266

Research | Princeton Plasma Physics Lab  

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

Overview Experimental Fusion Research Theoretical Fusion Research Basic Plasma Science Plasma Astrophysics Other Physics and Engineering Research PPPL Technical Reports Education Organization Contact Us Overview Experimental Fusion Research Theoretical Fusion Research Basic Plasma Science Plasma Astrophysics Other Physics and Engineering Research PPPL Technical Reports Research The U.S. Department of Energy's Princeton Plasma Physics Laboratory is dedicated to developing fusion as a clean and abundant source of energy and to advancing the frontiers of plasma science. The Laboratory pursues these goals through experiments and computer simulations of the behavior of plasma, the hot electrically charged gas that fuels fusion reactions and has a wide range of practical applications.

267

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

E-Print Network [OSTI]

in the discharge voltage range of 200-700 V. The arcing between the floating velvet electrodes and the plasma) Electronic mail: yraitses@pppl.gov 1 #12;The Hall thruster1 is a plasma discharge device with axial electric with the discharge voltage at a fixed magnetic field. The observations reported here also extend the regimes wherein

268

Marina Gorelenkova | Princeton Plasma Physics Lab  

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

Marina Gorelenkova Computational Project Engineer, Plasma Physics Laboratory. Contact Information Phone: 609-243-2137 Email: mgorelen...

269

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

270

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

2012-06-07T23:59:59.000Z

271

PPPL Open House | Princeton Plasma Physics Lab  

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

June 1, 2013, 9:00am to 4:00pm Open House at Princeton Plasma Physics Laboratory PPPL Open House Hot Plasma, Cool Science: Princeton Plasma Physics Lab Open House on June 1 Mark...

272

Michigan Institute for Plasma Science  

E-Print Network [OSTI]

of the Program in Plasma Physics and Professor of Astrophysical Sciences at Princeton University. He also serves as Associate Director for Academic Affairs at the Princeton Plasma Physics Laboratory. DrMichigan Institute for Plasma Science and Engineering Seminar Compressing Waves in Plasma

Shyy, Wei

273

Physics of Neutralization of Intense Charged Particle Beam Pulses by a Background Plasma  

E-Print Network [OSTI]

Startsev, A.B Sefkow Princeton Plasma Physics Laboratoryand A. B. Sefkow 1 Princeton Plasma Physics Laboratory,

Kaganovich, I.D.

2010-01-01T23:59:59.000Z

274

Working Principle of the Hollow-Anode Plasma Source Hollow-Anode Plasma  

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

36240 36240 Plasma Sources Science and Technology 4 (1995) 571-575. Working Principle of the Hollow-Anode Plasma Source André Anders and Simone Anders Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720 ABSTRACT The hollow-anode discharge is a special form of glow discharge. It is shown that a drastically reduced anode area is responsible for a positive anode voltage drop of 30-40 V and an increased anode sheath thickness. This leads to an ignition of a relatively dense plasma in front of the anode hole. Langmuir probe measurements inside a specially designed hollow anode plasma source give an electron density and temperature of n e = 10 9 -10 11 cm -3 and T e = 1 - 3 eV, respectively (nitrogen, current 100 mA, flow rate 5-50 scc/min). Driven by a pressure gradient, the "anode" plasma is blown through the anode hole and forms a bright plasma jet streaming with supersonic velocity (Mach number 1.2). The plasma stream can be used, for instance, in plasma-assisted deposition of thin films

275

Plasma jets and plasma bullets  

Science Journals Connector (OSTI)

Plasma plumes, or plasma jets, belong to a large family of gas discharges whereby the discharge plasma is extended beyond the plasma generation region into the surrounding ambience, either by a field (e.g. electromagnetic, convective gas flow, or shock wave) or a gradient of a directionless physical quantity (e.g. particle density, pressure, or temperature). This physical extension of a plasma plume gives rise to a strong interaction with its surrounding environment, and the interaction alters the properties of both the plasma and the environment, often in a nonlinear and dynamic fashion. The plasma is therefore not confined by defined physical walls, thus extending opportunities for material treatment applications as well as bringing in new challenges in science and technology associated with complex open-boundary problems. Some of the most common examples may be found in dense plasmas with very high dissipation of externally supplied energy (e.g. in electrical, optical or thermal forms) and often in or close to thermal equilibrium. For these dense plasmas, their characteristics are determined predominantly by strong physical forces of different fields, such as electrical, magnetic, thermal, shock wave, and their nonlinear interactions [1]. Common to these dense plasma plumes are significant macroscopic plasma movement and considerable decomposition of solid materials (e.g. vaporization). Their applications are numerous and include detection of elemental traces, synthesis of high-temperature materials and welding, laser--plasma interactions, and relativistic jets in particle accelerators and in space [2]–[4]. Scientific challenges in the understanding of plasma jets are exciting and multidisciplinary, involving interweaving transitions of all four states of matter, and their technological applications are wide-ranging and growing rapidly. Using the Web of Science database, a search for journal papers on non-fusion plasma jets reveals that a long initial phase up to 1990 with only 31 papers per year on average, and a total of some 1300 papers, precedes a considerable growth of some 35–50% in research activity every five years, over the last 20 years or so. As shown in the table, the annual dissemination of the field is more than 1600 papers and the total number of papers is in excess of 20000. This upwards trajectory is typical of a strong and growing subject area in physical science, with considerable capacity in both fundamental science and applications. PeriodNumber of papersPapers per annum 1948–1990130031 1991–19952279456 1996–20003447689 2001–20054571914 2006–201066401328 2011 1658 In many of the dense plasma jets discussed above, strong physical forces generated by the plasma are often desired and this favours plasma generation at elevated gas pressure, including atmospheric pressure, which favours a high level of gas ionization. Historically it has been challenging to reduce and control the strong physical forces in high-pressure plasmas for applications where these are unwanted, for example, surface modification of polymeric sheets [5]. Indeed, there is a real need for a vast range of material processing applications at temperatures below 100oC (or below 400 K) and this favours atmospheric-pressure plasma jets sustained far from thermal equilibrium with the dissipated electrical energy largely used not in heat generation but in unleashing non-equilibrium chemical reactions. The long-standing difficulty of effectively controlling the level of gas ionization at atmospheric pressure was overcome by the technological breakthrough of achieving atmospheric-pressure glow discharges in the late 1980s [6]. A related challenge stemming from high collisionality of atmospheric-pressure plasmas (v >> ?0) means that large-area plasmas sustained between parallel-plate electrodes are very susceptible to strong plasma instabilities when molecular gases are introduced for processing applications. This led to an effective technological solution in the early to late 1990s of confining atmospheric plasmas in a small v

M G Kong; B N Ganguly; R F Hicks

2012-01-01T23:59:59.000Z

276

LANL | Physics | Inertial Confinement Fusion and High Energy Density  

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

Inertial confinement and high density Inertial confinement and high density plasma physics Using the world's most powerful lasers, Physics Division scientists are aiming to create thermonuclear burn in the laboratory. The experimental research of the Physics Division's Inertial Confinement Fusion program is conducted at the National Ignition Facility at Lawrence Livermore National Laboratory, the OMEGA Laser Facility at the University of Rochester, and the Trident Laser Facility at Los Alamos. Within inertial confinement fusion and the high energy density area, Los Alamos specializes in hohlraum energetics, symmetry tuning, warm dense matter physics, and hydrodynamics in ultra-extreme conditions. When complete, this research will enable the exploitation of fusion as an energy resource and will enable advanced research in stockpile stewardship

277

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

278

Engineering | Princeton Plasma Physics Lab  

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

developing an advanced power switch Scientists at the U.S. Department of Energy's (DOE) Princeton Plasma Physics Laboratory (PPPL) are assisting General Electric Co. in...

279

Tours | Princeton Plasma Physics Lab  

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

Contract Documents Speakers Bureau Tours Virtual Tour Tours Tour Arrangements at the Princeton Plasma Physics Laboratory Come see first-hand the exciting world of fusion...

280

News | Princeton Plasma Physics Lab  

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

Simulation of microturbulence in a tokamak fusion device. (Credit: Chad Jones and Kwan-Liu Ma, University of California, Davis; Stephane Ethier, 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.


281

Education | Princeton Plasma Physics Lab  

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

Education Science Education Welcome to the Science Education Department at the Princeton Plasma Physics Laboratory (PPPL), where we combine the lab's core research activities with...

282

News | Princeton Plasma Physics Lab  

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

collaborators push for energy solutions By Catherine Shen Stewart Prager, director of the Princeton Plasma Physics Laboratory, gives the opening talk Nov. 14 at the third annual...

283

E-Print Network 3.0 - axisymmetric tokamak plasmas Sample Search...  

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

Princeton Plasma Physics Laboratory, Theory Department Collection: Plasma Physics and Fusion 3 EFFICIENCY AND SCALING OF CURRENT DRIVE AND REFUELLING Summary: of plasma cooling...

284

E-Print Network 3.0 - argon rf plasma Sample Search Results  

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

- Princeton Plasma Physics Laboratory Collection: Plasma Physics and Fusion 6 REVERSE-VORTEX PLASMA STABILIZATION: EXPERIMENTS AND NUMERICAL SIMULATION Summary: -Frequency (RF)...

285

Los Alamos National Laboratory names cleanup subcontractors  

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

as a backdrop to research and innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new materials. Los Alamos National Laboratory...

286

Using rf impedance probe measurements to determine plasma potential and the electron energy distribution  

SciTech Connect (OSTI)

Earlier work has demonstrated the usefulness of a network analyzer in plasma diagnostics using spherical probes in the thin sheath limit. The rf signal applied to the probe by the network analyzer is small in magnitude compared to probe bias voltages, and the instrument returns both real and imaginary parts of the complex plasma impedance as a function of frequency for given bias voltages. This information can be used to determine sheath resistance, sheath density profiles, and a technique for measuring electron temperature. The present work outlines a method for finding plasma potential and the electron energy distribution within a limited energy range. The results are compared to those using conventional Langmuir probe techniques. The rf method has general application to diverse areas of plasma investigations when the plasma is uniform and probe dimensions are much less than the size of the plasma. These applications include laboratory and space environments.

Walker, D. N. [Global Strategies Group, Inc., Crofton, Maryland 21114 (United States); Fernsler, R. F.; Blackwell, D. D.; Amatucci, W. E. [Plasma Physics Division, Naval Research Laboratory, 4555 Overlook Ave., Washington, DC 20375 (United States)

2010-11-15T23:59:59.000Z

287

We report the first production of high beta plasma confined in a fully levitated laboratory dipole using neutral gas fueling and electron  

E-Print Network [OSTI]

4500 A / 50 V Power supply Resistive coil allows for rapid shutdown Realtime digital control computer Interlocks Coil and Bus temperature and resistance monitoring LDX Control Room Laser Position Detectors QNX sufficient neutral gas is supplied to the plasma. As compared to previous studies in which the internal coil

288

5 - Surface Wave Plasma Sources  

Science Journals Connector (OSTI)

Publisher Summary This chapter summarizes the advantages of the surface wave (SW) plasma sources. It includes a summary of the wave and plasma properties of SW sustained plasma columns, review of the essential parts composing a SW plasma source; describes a family of efficient SW launchers for such plasma sources, dwells on three typical experimental arrangements and a brief summary recalling the advantages of SW plasma sources. Surface wave discharges have the advantage of the broadest operating conditions in terms of frequency, tube dimensions and shape, and gas pressure. For example they can be utilized over both the RF (radiofrequency) and microwave domains, which permits one to optimize given processes as a function of frequency (generally through changes in the electron energy distribution function). A further advantage of SW plasmas is that they are the best modeled HF plasmas. This provides insight into HF discharges in general since, to a first approximation, the local plasma properties of SW discharges are the same as in all RF and microwave discharges under given discharge conditions, and for a given HF power density deposited in the plasma. Compared to other RF and microwave plasma sources, SW discharges are undoubtedly the most flexible ones. They also are efficient discharges since very little HF power is lost in the impedance matching circuit. Finally, a major future avenue for these discharges is their operation as magnetized plasmas. As a first approach to presenting surface wave (SW) plasma sources, let us consider their distinctive features with respect to the other plasma sources described in the book:o1. The discharge can be sustained far away from the active zone of the field applicator. This is because the electric field supporting the discharge is provided by a wave that carries away the power from the applicator. It is an electromagnetic surface wave whose sole guiding structure is the plasma column that it sustains and the dielectric tube enclosing it [1]–[3]. This is, thus, a non-cumbersome method for producing long plasma columns; plasma columns up to 6 meters in length have been achieved in our laboratory while launching the wave with a field applicator that surrounded the discharge tube over a few centimeters in length only. [4][5] 2. The range of the applied field frequency f=?/2? is the broadest of all kinds of high frequency (HF) sustained plasma sources. We have succeeded in realizing HF power transfer to the discharge efficiently from approximately 10 \\{MHz\\} to 10 \\{GHz\\} [6] and, with impaired coupling efficiency, down to 200 kHz [7]. This frequency range includes radiofrequencies (RF) and the lower part of the microwave frequency spectrum; we use the term high frequencies to designate RF as well as microwave frequencies. An interesting aspect of this frequency flexibility is the possibility of acting on the electron energy distribution function (EEDF) to optimize a given plasma process [8]. 3. The gas pressure range is extremely large. On the one hand, one can operate SW discharges in the sub-mtorr range under electron cyclotron resonance (ECR) conditions, [9] while, on the other hand, it is possible to sustain a stable plasma of a few millimeters diameter at pressures at least a few times atmospheric pressure [10]. 4. The range of plasma, density, n, is very large. At reduced pressure and with f in the few \\{MHz\\} range, n, can be as low as 108 cm?3, [7] while at atmospheric pressure it can exceed 1015 cm?3[10] A related parameter is the degree of ionization ?i, i.e. the plasma density relative to the initial neutral atom concentration. Under ECR conditions, for example with f=2.45 \\{GHz\\} where n can reach up to a few 1012 cm?3, ?i ranges approximately from 0.1–10%, whereas in the above-mentioned atmospheric pressure case, it is smaller than 10?4. The higher n, the higher the rate of plasma processes depending on ions or on neutral particles (e.g., atoms, radicals) when the latter are obtained through electron collisions [8]. Large ?i values favor the existence of

Michel Moisan; Joëlle Margot; Zenon Zakrzewski

1996-01-01T23:59:59.000Z

289

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

E-Print Network [OSTI]

LABORATORY PPPL PPPL-4010 PPPL-4010 #12;PPPL Report Disclaimers Full Legal Disclaimer This report or any agency thereof or its contractors or subcontractors. PPPL Report Availability This report web site in Fiscal Year 2005. The home page for PPPL Reports and Publications is: http://www.pppl

290

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

E-Print Network [OSTI]

PHYSICS LABORATORY PPPL PPPL-4078 PPPL-4078 #12;PPPL Report Disclaimers Full Legal Disclaimer This report or any agency thereof or its contractors or subcontractors. PPPL Report Availability This report web site in Fiscal Year 2005. The home page for PPPL Reports and Publications is: http://www.pppl

291

Proposal for Submissions of New ITER Plasmas to the Profile Database Robert Budny (PPPL)  

E-Print Network [OSTI]

) 3. Certify each plasma before it is tried PRINCETON PLASMA PHYSICS LABORATORY PPPL 1 #12 or marginally stable PRINCETON PLASMA PHYSICS LABORATORY PPPL 2 #12;Why Time-Dependent Self-linearities and strong coupling of plasma conditions and current drive PRINCETON PLASMA PHYSICS LABORATORY PPPL 3 #12

Budny, Robert

292

Laboratory disputes citizens' lawsuit  

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

Lab disputes ctizens' lawsuit Lab disputes ctizens' lawsuit Laboratory disputes citizens' lawsuit Lab officials expressed surprise to a lawsuit alleging noncompliance with the federal Clean Water Act filed today by citizens groups. February 7, 2008 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 innovation covering multi-disciplines from bioscience, sustainable energy sources, 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 innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new materials. Contact James E. Rickman

293

Labs at-a-Glance: Ames Laboratory | U.S. DOE Office of Science (SC)  

Office of Science (SC) Website

Ames Laboratory Ames Laboratory Laboratories Ames Laboratory Argonne National Laboratory Brookhaven National Laboratory Fermi National Accelerator Laboratory Lawrence Berkeley National Laboratory Oak Ridge National Laboratory Pacific Northwest National Laboratory Princeton Plasma Physics Laboratory SLAC National Accelerator Laboratory Thomas Jefferson National Accelerator Facility Laboratory Policy and Evaluation Safety, Security and Infrastructure Laboratory Science Highlights Contact Information Office of Science U.S. Department of Energy 1000 Independence Ave., SW Washington, DC 20585 P: (202) 586-5430 Labs at-a-Glance: Ames Laboratory Print Text Size: A A A RSS Feeds FeedbackShare Page Ames Laboratory Logo Visit the Ames Laboratory website External link Ames Laboratory Quick Facts

294

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

E-Print Network [OSTI]

1 and J. W. Kwan 2 Princeton Plasma Physics Laboratory, P.California 94720 and Princeton Plasma Physics Laboratory P.Department of Energy by Princeton Plasma Physics Laboratory

Kwan, J.W.

2008-01-01T23:59:59.000Z

295

Nonaxisymmetric magnetorotational instability in ideal and viscous plasmas  

SciTech Connect (OSTI)

The excitation of magnetorotational instability (MRI) in rotating laboratory plasmas is investigated. In contrast to astrophysical plasmas, in which gravitation plays an important role, in laboratory plasmas it can be neglected and the plasma rotation is equilibrated by the pressure gradient. The analysis is restricted to the simple model of a magnetic confinement configuration with cylindrical symmetry, in which nonaxisymmetric perturbations are investigated using the local approximation. Starting from the simplest case of an ideal plasma, the corresponding dispersion relations are derived for more complicated models including the physical effects of parallel and perpendicular viscosities. The Friemann-Rotenberg approach used for ideal plasmas is generalized for the viscous model and an analytical expression for the instability boundary is obtained. It is shown that, in addition to the standard effect of radial derivative of the rotation frequency (the Velikhov effect), which can be destabilizing or stabilizing depending on the sign of this derivative in the ideal plasma, there is a destabilizing effect proportional to the fourth power of the rotation frequency, or, what is the same, to the square of the plasma pressure gradient, and to the square of the azimuthal mode number of the perturbations. It is shown that the instability boundary also depends on the product of the plasma pressure and density gradients, which has a destabilizing effect when it is negative. In the case of parallel viscosity, the MRI looks like an ideal instability independent of viscosity, while, in the case of strong perpendicular viscosity, it is a dissipative instability with the growth rate inversely proportional to the characteristic viscous decay rate. We point out, however, that the modes of the continuous range of the magnetohydrodynamics spectrum are not taken into account in this paper, and they can be more dangerous than those that are considered.

Mikhailovskii, A. B.; Erokhin, N. N. [Institute of Nuclear Fusion, Russian Research Centre Kurchatov Institute, 1, Kurchatov Sq., Moscow 123182 (Russian Federation); Lominadze, J. G. [Kharadze Abastumani National Astrophysical Observatory, 2a, Kazbegi Ave., Tbilisi 0160, Georgia (United States); Galvao, R. M. O. [Physics Institute, University of Sao Paulo, Cidade Universitaria, 05508-900, Sao Paulo (Brazil); Brazilian Center for Physics Research, Rua Xavier Sigaud, 150, 22290-180, Rio de Janeiro (Brazil); Churikov, A. P. [Syzran Branch of Samara Technical University, 45, Sovetskaya Str., Syzran, Samara Region 446001 (Russian Federation); Smolyakov, A. I. [Institute of Nuclear Fusion, Russian Research Centre Kurchatov Institute, 1, Kurchatov Sq., Moscow 123182 (Russian Federation); University of Saskatchewan, 116 Science Place, Saskatoon, Saskatchewan S7N 5E2 (Canada); Tsypin, V. S. [Brazilian Center for Physics Research, Rua Xavier Sigaud, 150, 22290-180, Rio de Janeiro (Brazil)

2008-05-15T23:59:59.000Z

296

Plasma Processing Of Hydrocarbon  

SciTech Connect (OSTI)

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

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

2007-05-01T23:59:59.000Z

297

Working Principle of the Hollow-Anode Plasma Source André Anders and Simone Anders  

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

Working Principle of the Hollow-Anode Plasma Source Working Principle of the Hollow-Anode Plasma Source André Anders and Simone Anders Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720 Abstract The hollow-anode discharge is a special form of glow discharge. It is shown that a drastically reduced anode area is responsible for a positive anode voltage drop of 30-40 V and an increased anode sheath thickness. This leads to an ignition of a relatively dense plasma in front of the anode hole. Langmuir probe measurements inside a specially designed hollow anode plasma source give an electron density and temperature of n e = 10 9 - 10 11 cm -3 and T e = 1 - 3 eV, respectively (nitrogen, current 100 mA, flow rate 5-50 scc/min). Driven by a pressure gradient, the "anode" plasma is blown through

298

Current Drive in Recombining Plasma  

SciTech Connect (OSTI)

The Langevin equations describing the average collisional dynamics of suprathermal particles in nonstationary plasma remarkably admit an exact analytical solution in the case of recombining plasma. The current density produced by arbitrary particle fluxes is derived including the effect of charge recombination. Since recombination has the effect of lowering the charge density of the plasma, thus reducing the charged particle collisional frequencies, the evolution of the current density can be modified substantially compared to plasma with fixed charge density. The current drive efficiency is derived and optimized for discrete and continuous pulses of current, leading to the discovery of a nonzero "residual" current density that persists indefinitely under certain conditions, a feature not present in stationary plasmas.

P.F. Schmit and N.J. Fisch

2012-05-15T23:59:59.000Z

299

Robert J Goldston | Princeton Plasma Physics Lab  

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

Society. From 1997 to 2009, he served as Director of the U.S. Department of Energy's Princeton Plasma Physics Laboratory (PPPL), a collaborative national center for plasma and...

300

Press Releases | Princeton Plasma Physics Lab  

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

the highest strength are shown in yellow. Researchers at the U.S. Department of Energy's Princeton Plasma Physics Laboratory (PPPL) and the Max Planck Institute of Plasma Physics...

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

Press Releases Archive | Princeton Plasma Physics Lab  

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

the highest strength are shown in yellow. Researchers at the U.S. Department of Energy's Princeton Plasma Physics Laboratory (PPPL) and the Max Planck Institute of Plasma Physics...

302

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

303

Characterization of a low-energy constricted-plasma source  

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

40374 (text only) 40374 (text only) Review. Sci. Instruments 69 (1998) 1340-1343. Characterization of a low-energy constricted-plasma source André Anders 1 and Michael Kühn 2 1 Ernest Orlando Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720 2 Institute of Physics, Technical University of Chemnitz, 09107 Chemnitz, Germany ABSTRACT The construction and principle of operation of the Constricted-Plasma Source are described. A supersonic plasma stream is produced by a special form of a dc-glow discharge, the constricted glow discharge. The discharge current and gas flow pass through an orifice of small diameter (constriction) which causes a space charge double layer but also serves as a nozzle to gasdynamically accelerate the plasma flow. Plasma parameters have been measured using Langmuir probes, optical emission spectroscopy, and a plasma monitor for mass-resolved energy measurements. Experiments have been done with nitrogen as the discharge gas. It was found that the energy distribution of both atomic and molecular ions have two peaks at about 5 eV and 15 eV, and the energy of almost all ions is less than 20 eV. The ionization efficiency decreases with increasing gas flow. The downstream plasma density is relatively low but activated species such as excited molecules and radicals contribute to film growth when the source is used for reactive film deposition

304

Plasma Chemistry and Plasma Processing, Vol. 12, No.4, 1992 Infrared Radiation from an Arc Plasma and Its  

E-Print Network [OSTI]

of an atmospheric-pressure arc plasma are described from the viewpoint of continuorts radiation tlieory of the atmospheric arc plasma column is very sensitive to the electron density in the near infrared frequency rangeB ) Plasma Chemistry and Plasma Processing, Vol. 12, No.4, 1992 Infrared Radiation from an Arc

Eagar, Thomas W.

305

Time-dependent Integrated Modeling of Burning Plasmas TTF and US-Japan Workshop on Energetic Particle Physics  

E-Print Network [OSTI]

PRINCETON PLASMA PHYSICS LABORATORY PPPL 1 #12;Why traditional predictions of burning plasmas are inadequate PRINCETON PLASMA PHYSICS LABORATORY PPPL 2 #12;Why Time-Dependent Self-Consistent Integrated Modeling of plasma conditions and current drive PRINCETON PLASMA PHYSICS LABORATORY PPPL 3 #12;Goals of this Talk

Budny, Robert

306

Lewis D Meixler | Princeton Plasma Physics Lab  

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

Lewis D Meixler Head, Technology Transfer and Applications Research Lew Meixler is presently Head of the Princeton Plasma Physics Laboratory (PPPL) Office of Technology Transfer,...

307

Colloquia Archive | Princeton Plasma Physics Lab  

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

Achieving 10MW Fusion Power in TFTR: a Retrospective November 18, 2014 Dr. Michael Bell Princeton Plasma Physics Laboratory COLLOQUIUM: Smaller & Sooner: The ARC Pilot Design for...

308

Theoretical Fusion Research | Princeton Plasma Physics Lab  

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

Theory Department The fusion energy sciences mission of the Theory Department at the Princeton Plasma Physics Laboratory (PPPL) is to help provide the scientific foundations...

309

Press Releases Archive | Princeton Plasma Physics Lab  

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

greenhouse gas emissions by 48 percent between 2008 and 2011. The Department of Energy's Princeton Plasma Physics Laboratory has received a Sustainability Award from the...

310

Power system design | Princeton Plasma Physics Lab  

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

developing an advanced power switch Scientists at the U.S. Department of Energy's (DOE) Princeton Plasma Physics Laboratory (PPPL) are assisting General Electric Co. in...

311

AC power | Princeton Plasma Physics Lab  

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

developing an advanced power switch Scientists at the U.S. Department of Energy's (DOE) Princeton Plasma Physics Laboratory (PPPL) are assisting General Electric Co. in...

312

Star Power | Princeton Plasma Physics Lab  

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

Star Power Star Power The U.S. Department of Energy's Princeton Plasma Physics Laboratory has released "Star Power," a new informational video that uses dramatic and beautiful...

313

PathSci | Princeton Plasma Physics Lab  

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

PathSci The Princeton Plasma Physics Laboratory's Pathways to Science program is now partnering with ARISE (Advanced Research and Innovation in Science Education) and the...

314

Allan H Reiman | Princeton Plasma Physics Lab  

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

Cornell University and a staff position at the University of Maryland before joining the Princeton Plasma Physics Laboratory in 1981. He has been a consultant at Science...

315

Michael D Williams | Princeton Plasma Physics Lab  

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

the Engineer's Engineer, sets standard for excellence As an early career engineer at the Princeton Plasma Physics Laboratory (PPPL), Mike Williams found himself in the midst of a...

316

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

317

Measurement and Modeling of Density-Sensitive Lines of Fe XIII in the Extreme Ultraviolet  

SciTech Connect (OSTI)

We present an analysis of the spectral emission of Fe XIII near 200 {angstrom}. High resolution spectra were recorded at two densities ({approx} x 10{sup 11} and {approx} 10{sup 13} cm{sup -3}) in the laboratory and compared to collisional radiative model calculations based on the CHIANTI data base as well as to models using atomic data from distorted-wave and R-matrix calculations. The Fe XIII lines in this wavelength range are sensitive indicators of plasma density below {approx} 10{sup 11} cm{sup -3}. The laboratory data thus test the calculations in the astrophysically high-density limit. Significant differences between the measurements and models were found for several line ratios. Differences in the wavelengths employed in the different models also changed the agreement with the measurements. Best agreement was found in the comparisons with CHIANTI.

Yamamoto, N; Kato, T; Beiersdorfer, P; Lepson, J K

2008-01-17T23:59:59.000Z

318

Nonlinear Mixing of Electromagnetic Waves in Plasmas  

Science Journals Connector (OSTI)

...nc, where ne is the plasma density and n, is...regions X(3) ofa plasma can be orders of magnitude larger than those for other...Conclusions The beat-wave plasma interaction is an important...rapidly growing research area in plasma physics and...

V. STEFAN; B. I. COHEN; C. JOSHI

1989-01-27T23:59:59.000Z

319

Labs at-a-Glance: Oak Ridge National Laboratory | U.S. DOE Office of  

Office of Science (SC) Website

Oak Ridge Oak Ridge National Laboratory Laboratories Ames Laboratory Argonne National Laboratory Brookhaven National Laboratory Fermi National Accelerator Laboratory Lawrence Berkeley National Laboratory Oak Ridge National Laboratory Pacific Northwest National Laboratory Princeton Plasma Physics Laboratory SLAC National Accelerator Laboratory Thomas Jefferson National Accelerator Facility Laboratory Policy and Evaluation Safety, Security and Infrastructure Laboratory Science Highlights Contact Information Office of Science U.S. Department of Energy 1000 Independence Ave., SW Washington, DC 20585 P: (202) 586-5430 Labs at-a-Glance: Oak Ridge National Laboratory Print Text Size: A A A RSS Feeds FeedbackShare Page Oak Ridge National Laboratory Logo Visit the Oak Ridge National Laboratory

320

Labs at-a-Glance: Brookhaven National Laboratory | U.S. DOE Office of  

Office of Science (SC) Website

Brookhaven Brookhaven National Laboratory Laboratories Ames Laboratory Argonne National Laboratory Brookhaven National Laboratory Fermi National Accelerator Laboratory Lawrence Berkeley National Laboratory Oak Ridge National Laboratory Pacific Northwest National Laboratory Princeton Plasma Physics Laboratory SLAC National Accelerator Laboratory Thomas Jefferson National Accelerator Facility Laboratory Policy and Evaluation Safety, Security and Infrastructure Laboratory Science Highlights Contact Information Office of Science U.S. Department of Energy 1000 Independence Ave., SW Washington, DC 20585 P: (202) 586-5430 Labs at-a-Glance: Brookhaven National Laboratory Print Text Size: A A A RSS Feeds FeedbackShare Page Brookhaven National Laboratory Logo Visit the Brookhaven National 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.


321

Labs at-a-Glance: Argonne National Laboratory | U.S. DOE Office of Science  

Office of Science (SC) Website

Argonne National Argonne National Laboratory Laboratories Ames Laboratory Argonne National Laboratory Brookhaven National Laboratory Fermi National Accelerator Laboratory Lawrence Berkeley National Laboratory Oak Ridge National Laboratory Pacific Northwest National Laboratory Princeton Plasma Physics Laboratory SLAC National Accelerator Laboratory Thomas Jefferson National Accelerator Facility Laboratory Policy and Evaluation Safety, Security and Infrastructure Laboratory Science Highlights Contact Information Office of Science U.S. Department of Energy 1000 Independence Ave., SW Washington, DC 20585 P: (202) 586-5430 Labs at-a-Glance: Argonne National Laboratory Print Text Size: A A A RSS Feeds FeedbackShare Page Argonne National Laboratory Logo Visit the Argonne National Laboratory

322

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

323

Ultraprecision Finishing of Photomask Substrate by Utilizing Atmospheric Pressure Plasma  

Science Journals Connector (OSTI)

In the case of the atmospheric pressure plasma, localized high density plasma is generated around the electrode. Therefore, ... new ultra precision machining method which is named plasma chemical vaporization mac...

Kazuya Yamamura; Akihiro Fujiwara; Koji Ueno…

2007-01-01T23:59:59.000Z

324

Better Fusion Plasma Operating Scenarios are Being Explored and...  

Office of Science (SC) Website

can be accessed at relatively low plasma density, and then maintained as both density and power to the plasma are increased, as is expected to be the approach on ITER. Summary...

325

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

E-Print Network [OSTI]

­Zwicker Princeton Plasma Physics Laboratory, Box 451, Princeton, NJ 08543 azwicker@pppl.gov #12; 'Plasma Camp in laboratory investigations and in pedagogical projects for two weeks at Princeton University's Plasma Physics teachers held at the Princeton Plasma Physics Laboratory (PPPL), a national research facility funded

326

First Plasma Wave Observations at Neptune  

Science Journals Connector (OSTI)

...revealed that Neptune has a large and complex magnetosphere...first observations of plasma waves and low-frequency...from lightning. Such large dispersions would require path lengths and plasma densities that are much larger than anything plausible...

D. A. Gurnett; W. S. Kurth; R. L. Poynter; L. J. Granroth; I. H. Cairns; W. M. Macek; S. L. Moses; F. V. Coroniti; C. F. Kennel; D. D. Barbosa

1989-12-15T23:59:59.000Z

327

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

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

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

328

MIT Plasma Science & Fusion Center: research, alcator, pubs,...  

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

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

329

Gun Injection into a Microwave Plasma J. C. Sprott  

E-Print Network [OSTI]

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

Sprott, Julien Clinton

330

Newsletters | Princeton Plasma Physics Lab  

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

to the second issue of Quest, the annual magazine of the U.S. Department of Energy's Princeton Plasma Physics Laboratory (PPPL). We are pleased to provide this news of our...

331

News | Princeton Plasma Physics Lab  

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

the image and select "Save Image" or "Save Image As..." Stewart Prager, director of the Princeton Plasma Physics Laboratory, gives the opening talk Nov. 14 at the third annual...

332

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

333

Labs at-a-Glance: Pacific Northwest National Laboratory | U.S. DOE Office  

Office of Science (SC) Website

Pacific Pacific Northwest National Laboratory Laboratories Ames Laboratory Argonne National Laboratory Brookhaven National Laboratory Fermi National Accelerator Laboratory Lawrence Berkeley National Laboratory Oak Ridge National Laboratory Pacific Northwest National Laboratory Princeton Plasma Physics Laboratory SLAC National Accelerator Laboratory Thomas Jefferson National Accelerator Facility Laboratory Policy and Evaluation Safety, Security and Infrastructure Laboratory Science Highlights Contact Information Office of Science U.S. Department of Energy 1000 Independence Ave., SW Washington, DC 20585 P: (202) 586-5430 Labs at-a-Glance: Pacific Northwest National Laboratory Print Text Size: A A A RSS Feeds FeedbackShare Page Pacific Northwest National Laboratory Logo Visit the Pacific Northwest National

334

Labs at-a-Glance: Fermi National Accelerator Laboratory | U.S. DOE Office  

Office of Science (SC) Website

Fermi National Fermi National Accelerator Laboratory Laboratories Ames Laboratory Argonne National Laboratory Brookhaven National Laboratory Fermi National Accelerator Laboratory Lawrence Berkeley National Laboratory Oak Ridge National Laboratory Pacific Northwest National Laboratory Princeton Plasma Physics Laboratory SLAC National Accelerator Laboratory Thomas Jefferson National Accelerator Facility Laboratory Policy and Evaluation Safety, Security and Infrastructure Laboratory Science Highlights Contact Information Office of Science U.S. Department of Energy 1000 Independence Ave., SW Washington, DC 20585 P: (202) 586-5430 Labs at-a-Glance: Fermi National Accelerator Laboratory Print Text Size: A A A RSS Feeds FeedbackShare Page Fermi National Accelerator Laboratory Logo Visit the Fermi National Accelerator

335

Labs at-a-Glance: SLAC National Accelerator Laboratory | U.S. DOE Office of  

Office of Science (SC) Website

SLAC National SLAC National Accelerator Laboratory Laboratories Ames Laboratory Argonne National Laboratory Brookhaven National Laboratory Fermi National Accelerator Laboratory Lawrence Berkeley National Laboratory Oak Ridge National Laboratory Pacific Northwest National Laboratory Princeton Plasma Physics Laboratory SLAC National Accelerator Laboratory Thomas Jefferson National Accelerator Facility Laboratory Policy and Evaluation Safety, Security and Infrastructure Laboratory Science Highlights Contact Information Office of Science U.S. Department of Energy 1000 Independence Ave., SW Washington, DC 20585 P: (202) 586-5430 Labs at-a-Glance: SLAC National Accelerator Laboratory Print Text Size: A A A RSS Feeds FeedbackShare Page SLAC National Accelerator Laboratory Logo Visit the SLAC National Accelerator

336

Labs at-a-Glance: Lawrence Berkeley National Laboratory | U.S. DOE Office  

Office of Science (SC) Website

Lawrence Lawrence Berkeley National Laboratory Laboratories Ames Laboratory Argonne National Laboratory Brookhaven National Laboratory Fermi National Accelerator Laboratory Lawrence Berkeley National Laboratory Oak Ridge National Laboratory Pacific Northwest National Laboratory Princeton Plasma Physics Laboratory SLAC National Accelerator Laboratory Thomas Jefferson National Accelerator Facility Laboratory Policy and Evaluation Safety, Security and Infrastructure Laboratory Science Highlights Contact Information Office of Science U.S. Department of Energy 1000 Independence Ave., SW Washington, DC 20585 P: (202) 586-5430 Labs at-a-Glance: Lawrence Berkeley National Laboratory Print Text Size: A A A RSS Feeds FeedbackShare Page Lawrence Berkeley National Laboratory Logo Visit the Lawrence Berkeley National

337

Onset and Saturation of the Kink Instability in a Current-Carrying Line-Tied Plasma W. F. Bergerson, C. B. Forest,* G. Fiksel, D. A. Hannum, R. Kendrick, J. S. Sarff, and S. Stambler  

E-Print Network [OSTI]

-tied cylindrical plasmas [1­4]. Laboratory plasmas, such as the tokamak, reversed field pinch, and spheromak

Wisconsin at Madison, University of

338

Los Alamos National Laboratory, Sandia Labs, other major employers...  

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

as a backdrop to research and innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new materials. Los Alamos National Laboratory...

339

Los Alamos National Laboratory's environmental data now viewable...  

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

as a backdrop to research and innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new materials. Los Alamos National Laboratory...

340

Los Alamos National Laboratory receives Recovery Act funds  

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

as a backdrop to research and innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new materials. Los Alamos National 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.


341

Los Alamos National Laboratory, LANS develop new mentor-protégé...  

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

as a backdrop to research and innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new materials. Los Alamos National Laboratory...

342

Area schools get new computers through Los Alamos National Laboratory...  

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

as a backdrop to research and innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new materials. Los Alamos National Laboratory...

343

Laboratory program helps small businesses  

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

Laboratory program helps small businesses Laboratory program helps small businesses Laboratory program helps small businesses The NMSBA allows for-profit small businesses to request technical assistance that capitalizes on the unique expertise and capabilities of Los Alamos and Sandia national laboratories. June 23, 2010 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 innovation covering multi-disciplines from bioscience, sustainable energy sources, 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 innovation covering multi-disciplines from bioscience, sustainable energy

344

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...

345

National Spherical Torus Experiment (NSTX) | Princeton Plasma...  

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

the physics principles of spherically shaped plasmas -- hot ionized gases in which nuclear fusion will occur under the appropriate conditions of temperature, density, and...

346

Laboratory Fellows  

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

were confirmed by the Laboratory Director. Brenda Dingus has pioneered work in gamma-ray bursts and is a major contributor to the relatively young scientific field of...

347

Laboratory Operations  

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

hydrological controls on carbon cycling in flood plain ecosystems into Earth System Models. - 5814 A neutron detector like this one at Los Alamos National Laboratory is...

348

Transport processes in space plasmas  

SciTech Connect (OSTI)

This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The project represents a comprehensive research effort to study plasma and field transport processes relevant for solar-terrestrial interaction, involving the solar wind and imbedded magnetic field and plasma structures, the bow shock of the Earth`s magnetosphere and associated waves, the Earth`s magnetopause with imbedded flux rope structures and their connection with the Earth, plasma flow in the Earth`s magnetotail, and ionospheric beam/wave interactions. The focus of the work was on the interaction between plasma and magnetic and electric fields in the regions where different plasma populations exist adjacent to or superposed on each other. These are the regions of particularly dynamic plasma behavior, important for plasma and energy transport and rapid energy releases. The research addressed questions about how this interaction takes place, what waves, instabilities, and particle/field interactions are involved, how the penetration of plasma and energy through characteristic boundaries takes place, and how the characteristic properties of the plasmas and fields of the different populations influence each other on different spatial and temporal scales. These topics were investigated through combining efforts in the analysis of plasma and field data obtained through space missions with theory and computer simulations of the plasma behavior.

Birn, J.; Elphic, R.C.; Feldman, W.C. [and others

1997-08-01T23:59:59.000Z

349

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

350

Reflectivity of nonideal plasmas  

Science Journals Connector (OSTI)

New results on optical reflectance measurements of shock-compressed dense xenon plasma at wavelengths ? = 532 nm and ? = 694 nm are reported. The investigations have been performed for nonideal plasma (? = 0.87–2.0) at densities ? = 0.27–3.84 g cm?3 and pressures P = 1.6–17 GPa. The obtained high optical reflectance values are characteristic of a metallic fluid and are evidence for a conducting state in the shocked xenon. Reflectance measurements at different wavelengths provide information about the density profile of the shock wave front.

Yu Zaporoghets; V Mintsev; V Gryaznov; V Fortov; H Reinholz; T Raitza; G Röpke

2006-01-01T23:59:59.000Z

351

Plasma turbulence  

SciTech Connect (OSTI)

The origin of plasma turbulence from currents and spatial gradients in plasmas is described and shown to lead to the dominant transport mechanism in many plasma regimes. A wide variety of turbulent transport mechanism exists in plasmas. In this survey the authors summarize some of the universally observed plasma transport rates.

Horton, W. [Univ. of Texas, Austin, TX (United States). Inst. for Fusion Studies; Hu, G. [Globalstar LP, San Jose, CA (United States)

1998-07-01T23:59:59.000Z

352

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

353

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

354

Large-Volume, Helicon-Plasma Source for Simulation Experiments of Space Plasmas  

E-Print Network [OSTI]

; e.g., plasma processing, nuclear fusion, and basic fields including space plasmas. Recently is discussed, considering the power balance between input and loss. It has been found that the radial density

Boyer, Edmond

355

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

356

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

357

Thermodynamics of a dusty plasma  

Science Journals Connector (OSTI)

In the present work, we develop the thermodynamics of a dusty plasma and give an equation of state for two cases: (a) when the dust forms a stationary background and the charge on the grain does not vary and (b) when the dust charge fluctuates either due to the fluctuations in the electron and ion number densities or due to the dust density variation. Application of the results to the various space plasma situations has been indicated.

B. P. Pandey

2004-02-27T23:59:59.000Z

358

Princeton Plasma Physics Laboratory NSTX Experimental Proposal  

E-Print Network [OSTI]

plan 1. Assume previous XP ends with standard He-GDC 2. 2-3 Gas only shots 2 puff (128266) and 4 puff - Run Coordinator: Date Responsible Division: Experimental Research Operations Chit Review Board AUTHORS: C. H. Skinner, R. Maingi, V. Soukhanovski, W. Blanchard DATE: 4/9/08 1. Overview of planned

Princeton Plasma Physics Laboratory

359

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

360

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

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]

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

362

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

363

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

364

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

365

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

366

Princeton Plasma Physics Laboratory NSTX Experimental Proposal  

E-Print Network [OSTI]

, the experiment will then attempt to determine the error-field penetration threshold scaling with B-field, shape, if some confidence can be gained that error fields have been minimized in NSTX, the penetration threshold ramp-rate to reach flat-top current at t=160ms for higher IP shots or use higher current reference

Princeton Plasma Physics Laboratory

367

Princeton Plasma Physics Laboratory NSTX Experimental Proposal  

E-Print Network [OSTI]

and height are determined by neutral penetration length. We would like to document SGI and CGI fueled pedestal conditions so that analytical models of neutral penetration can be applied. 3. Experimental run-mode discharge (1-2 shots) Repeat with LFS injector (Injector # 2) at identical rate and timing Use MPTS relative

Princeton Plasma Physics Laboratory

368

PROCEDURE COVER SHEET Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

Quality Assurance/Quality Control AC Power Maintenance and Operations Division Energy Conversion Systems Only" training for Administrative, Alarm Response, and Emergency Operations procedures must Engineering Environmental Restoration & Waste Management Division Water Systems Neutral Beam (Heating Systems

Princeton Plasma Physics Laboratory

369

Sandia National Laboratories: fundamental plasma physics  

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

Doppler Velocimeter EC Top Publications A Comparison of Platform Options for Deep-water Floating Offshore Vertical Axis Wind Turbines: An Initial Study Nonlinear Time-Domain...

370

Modeling Nuclear Fusion with an Ultracold Nonneutral Plasma  

SciTech Connect (OSTI)

In the hot dense interiors of stars and giant planets, nuclear fusion reactions are predicted to occur at rates that are greatly enhanced compared to those at low densities. The enhancement is caused by plasma screening of the repulsive Coulomb potential between nuclei, which increases the probability of the rare close collisions that are responsible for fusion. This screening enhancement is a small effect in the Sun, but is predicted to be much larger in dense objects such as white dwarf stars and giant planet interiors where the plasma is strongly correlated (i.e. where the Debye screening length is smaller than a mean interparticle spacing). However, strongly enhanced fusion reaction rates caused by plasma screening have never been definitively observed in the laboratory. This talk discusses a method for observing the enhancement using an analogy between nuclear energy and cyclotron energy in a cold nonneutral plasma in a strong magnetic field. In such a plasma, the cyclotron frequency is higher than other dynamical frequencies, so the kinetic energy of cyclotron motion is an adiabatic invariant. This energy is not shared with other degrees of freedom except through rare close collisions that break this invariant and couple the cyclotron motion to the other degrees of freedom. Thus, the cyclotron energy of an ion, like nuclear energy, can be considered to be an internal degree of freedom that is released only via rare close collisions. Furthermore, it has recently been shown that the rate of release of cyclotron energy is enhanced through plasma screening by precisely the same factor as that for the release of nuclear energy, because both processes rely on close collisions that are enhanced by plasma screening in the same way. Simulations and experiments measuring large plasma screening enhancements for the first time will be discussed, and the possibility of exciting and studying cyclotron burn fronts will also be considered.

Dubin, Daniel H. E. [Physics Dept., UCSD, 9500 Gilman Drive, La Jolla CA 92093-0319 (United States)

2007-08-02T23:59:59.000Z

371

SciTech Connect: plasma  

Office of Scientific and Technical Information (OSTI)

plasma Find plasma Find How should I search Scitech Connect ... Basic or Advanced? Basic Search Advanced × Advanced Search Options Full Text: Bibliographic Data: Creator / Author: Name Name ORCID Title: Subject: Identifier Numbers: Research Org.: Sponsoring Org.: Site: All Alaska Power Administration, Juneau, Alaska (United States) Albany Research Center (ARC), Albany, OR (United States) Albuquerque Complex - NNSA Albuquerque Operations Office, Albuquerque, NM (United States) Amarillo National Resource Center for Plutonium, Amarillo, TX (United States) Ames Laboratory (AMES), Ames, IA (United States) Argonne National Laboratory (ANL), Argonne, IL (United States) Argonne National Laboratory-Advanced Photon Source (United States) Atlanta Regional Office, Atlanta, GA (United States) Atmospheric Radiation Measurement (ARM)

372

Triton burnup in plasma focus plasmas  

Science Journals Connector (OSTI)

Pure deuterium plasma discharge from plasma focus breeds 1.01 MeV tritons via the D(d p)T fusion branch which has the same cross section as the D(d n)3He (E n =2.45 MeV) fusion branch. Tritons are trapped in and collide with the background deuterium plasma producing 14.1 MeV neutrons via the D(t n)4He reaction. The paper presents published in preliminary form as well as unpublished experimental data and theoretical studies of the neutron yield ratio R=Y n (14.1 MeV)/Y n (2.45 MeV). The experimental data were obtained from 1 MJ Frascati plasma focus operated at W=490 kJ with pure deuterium plasma (in the early 1980s). Neutrons were monitored using the nuclear activation method and nuclear emulsions. The present theoretical analysis of the experimental data is based on an exact adaptation of the binary encounter theory developed by Gryzinski. It is found that the experimentally defined value 1?10?3plasma domains of very high density (n?1021 cm?3) high temperature (kT?1 keV) and short trapping time (t 0?20 ns). These domains are known as efficient traps of MeV ions but are not the main source of D(d n)3He fusion.

Jan S. Brzosko; Jan R. Brzosko Jr.; Benjamin V. Robouch; Luigi Ingrosso

1995-01-01T23:59:59.000Z

373

Laboratory Directors  

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

S. Hecker (1985-1997) Donald M. Kerr (1979-1985) Harold M. Agnew (1970-1979) Norris Bradbury (1945-1970) J. Robert Oppenheimer (1943-1945) Laboratory Directors Harold M. Agnew...

374

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.

375

Cathodic Arc Plasma Deposition  

Office of Scientific and Technical Information (OSTI)

Cathodic Arc Plasma Deposition Cathodic Arc Plasma Deposition André Anders Lawrence Berkeley National Laboratory, University of California, 1 Cyclotron Road, Mailstop 53, Berkeley, California 94720 aanders@lbl.gov Abstract Cathodic arc plasma deposition is one of oldest coatings technologies. Over the last two decades it has become the technology of choice for hard, wear resistant coatings on cutting and forming tools, corrosion resistant and decorative coatings on door knobs, shower heads, jewelry, and many other substrates. The history, basic physics of cathodic arc operation, the infamous macroparticle problem and common filter solutions are reviewed. Cathodic arc plasmas stand out due to their high degree of ionization, with important consequences for film nucleation, growth, and efficient utilization of substrate bias. The

376

Long-wavelength density turbulence in the TFTR tokamak  

Science Journals Connector (OSTI)

Long-wavelength (k??itokamak plasma with auxiliary heating. Density fluctuations of n?/n>0.5% exist for k?tokamaks.

R. J. Fonck; G. Cosby; R. D. Durst; S. F. Paul; N. Bretz; S. Scott; E. Synakowski; G. Taylor

1993-06-14T23:59:59.000Z

377

Particle Simulation of Magnetically Confined Plasmas Princeton Plasma Physics Laboratory  

E-Print Network [OSTI]

. Lewandowski Beams: H. Qin, R. C. Davidson 1 #12;OUTLINE PPPL ¯ Progress in Particle Simulation ¯ Gyrokinetic of Relativistic Beams ¯ Summary and Conclusions 2 #12;Abstract PPPL ¯ Particle Simulation + Massively Parallel of the Vlasov-Maxwell System PPPL ¯ The Vlasov equation, � � · � ¡ � · � � ¼ · ½� ¢ ½ ¡ � ´ µ ¯ Particle Pushing

378

Density | OpenEI  

Open Energy Info (EERE)

Density Density Dataset Summary Description This dataset is part of a larger internal dataset at the National Renewable Energy Laboratory (NREL) that explores various characteristics of large solar electric (both PV and CSP) facilities around the United States. This dataset focuses on the land use characteristics for solar facilities that are either under construction or currently in operation. Source Land-Use Requirements for Solar Power Plants in the United States Date Released June 25th, 2013 (5 months ago) Date Updated Unknown Keywords acres area average concentrating solar power csp Density electric hectares km2 land land requirements land use land-use mean photovoltaic photovoltaics PV solar statistics Data application/vnd.openxmlformats-officedocument.spreadsheetml.sheet icon Master Solar Land Use Spreadsheet (xlsx, 1.5 MiB)

379

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.

380

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

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

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

382

First Sustained Burning Plasma. Starts in 2019.  

E-Print Network [OSTI]

-T fusion power density is approximated by: Plasma pressure in atmospheres We need >1MWm-3 for an economic system -- need a few Atmospheres of plasma pressure. Can we hold it with a magnetic field? MagneticITER JET (to scale) JET (to scale) First Sustained Burning Plasma. Starts in 2019. BASIC PARAMETERS

383

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

384

On interrelating laboratory experiments and geoplasma observations  

Science Journals Connector (OSTI)

The history, benefits, suitability and limitations of laboratory simulation of space plasma processes are reviewed. Aspects of waves, instabilities, nonlinearities, particle transport, reconnection and hydrodynamics are addressed in terms of interrelated experiments performed in space and in the laboratory. Over time, the degree to which the interrelated experiments can be compared has increased, thanks to improved diagnostic techniques in space and closer attention to matching dimensionless space parameters in the laboratory.

M E Koepke

2005-01-01T23:59:59.000Z

385

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

386

Federal Laboratory Consortium | The Ames Laboratory  

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

Federal Laboratory Consortium The Federal Laboratory Consortium for Technology Transfer (FLC) is the nationwide network of federal laboratories that provides the forum to develop...

387

CONTENTS I MAY 1992-VOL. 21, NO. 3 BURNING PLASMA EXPERIMENT SPECIAL  

E-Print Network [OSTI]

Princeton University, Princeton Plasma Physics Laboratory P.O. Box 451, Princeton, New Jersey 08543 G. H, Tennessee 37381 G. BATEMAN and M. G. BELL Princeton University, Princeton Plasma Physics Laboratory P.O. Box Princeton Plasma Physics Laboratory, I? 0. Box 451, Princeton, New Jersey 08543 M. PORKOLAB Massachusetts

388

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

E-Print Network [OSTI]

. Fisch are with the Princeton Plasma Physics Laboratory, Princeton, NJ 08540 USA (e-mail: yraitses1998 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 36, NO. 5, OCTOBER 2008 Controlling the Plasma Flow electron emis- sion. The thruster operation in this mode greatly expands the range of the plasma

389

1204 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 36, NO. 4, AUGUST 2008 Plasma Plume of Annular and  

E-Print Network [OSTI]

are with the Princeton Plasma Physics Laboratory, Princeton University, Princeton, NJ 08543-0451 USA (e-mail: fisch1204 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 36, NO. 4, AUGUST 2008 Plasma Plume of Annular potential induced within the plasma. Annular-geometry Hall thrusters tend to have narrower plumes. However

390

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

391

Plasma-beam interaction in a wiggler  

Science Journals Connector (OSTI)

The possibility of obtaining self-bunching of the beam, emission of coherent radiation and strong electrostatic fields in a plasma loaded free electron laser, is studied by means of a set of nonlinear self-consistent equations deduced from the Maxwell equations, the fluid plasma model, and the relativistic equations of motion for the electrons of the beam in the limit of plasma density much larger than the beam density.

V. Petrillo; A. Serbeto; C. Maroli; R. Parrella; R. Bonifacio

1995-06-01T23:59:59.000Z

392

Princeton Plasma Physics Lab - Inertial confinement fusion  

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

inertial-confinement-fusion An inertial-confinement-fusion An experimental process that uses lasers to compress plasma to sufficiently high temperatures and densities for fusion to occur. Such experiments are carried out in places such as the National Ignition Facility at the Lawrence Livermore National Laboratory in Livermore, California. en Fusion through the eyes of a veteran science journalist http://www.pppl.gov/news/2013/07/fusion-through-eyes-veteran-science-journalist-1

Author Daniel Clery recently published "A Piece of the Sun," a 320-page narrative of the history of fusion research and the

393

DUST-PLASMA INTERACTIONS  

SciTech Connect (OSTI)

The objective of our theoretical research under this grant over the past 3 years was to develop new understanding in a range of topics in the physics of dust-plasma interactions, with application to space and the laboratory. We conducted studies related to the physical properties of dust, waves and instabilities in both weakly coupled and strongly coupled dusty plasmas, and innovative possible applications. A major consideration in our choice of topics was to compare theory with experiments or observations, and to motivate new experiments, which we believe is important for developing this relatively new field. Our research is summarized, with reference to our list of journal publications.

Dr. M. Rosenberg

2010-01-05T23:59:59.000Z

394

Trapping of Gun-Injected Plasma by a Tokamak  

Science Journals Connector (OSTI)

It is shown that a plasma produced by a Marshall gun can be injected into and trapped by a tokamak plasma. Gun injection raises the line-averaged density and peaks the density profile. Trapping of the gun-injected plasma is explainable in terms of a depolarization current mechanism.

A. W. Leonard; R. N. Dexter; J. C. Sprott

1986-07-21T23:59:59.000Z

395

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

396

Laboratory Access | Sample Preparation Laboratories  

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

Access Access Planning Ahead Planning Ahead Please complete the Beam Time Request (BTR) and Support Request forms thourgh the User Portal. Thorough chemical and sample information must be included in your BTR. Support Request forms include a list of collaborators that require laboratory access and your group's laboratory equipment requests. Researcher safety is taken seriously at SLAC. Please remember that radioactive materials, nanomaterials, and biohazardous materials have additional safety requirements. Refer to the SSRL or LCLS Safety Offices for further guidance. Upon Arrival Upon Arrival Once you arrive you must complete training and access forms before accessing the Sample Preparation Laboratories (SPL). All Sample Prep Lab doors are locked with access key codes. Once your SPL

397

Sandia National Laboratories: Federal Laboratory Consortium Regional...  

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

& CapabilitiesCapabilitiesFederal Laboratory Consortium Regional Technology-Transfer Awards Salute Innovation, Commercialization at Sandia Federal Laboratory...

398

PPPL's dynamic diagnostic duo | Princeton Plasma Physics Lab  

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

Zarnstorff, deputy director for research at DOE's Princeton Plasma Physics Laboratory(PPPL), where the duo has worked for nearly four decades. "Over the years they have developed...

399

Research Mission - Rotating Wall Machine - UW Plasma Physics  

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

astrophysical jets. Laboratory plasmas, such as the tokamak, reversed field pinch and spheromak, are all susceptible to kink instabilities from the same excessive twisting in field...

400

Power System Design Engineer | Princeton Plasma Physics Lab  

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

System Design Engineer Department: Engineering Supervisor(s): John Lacenere Staff: ENG 04 Requisition Number: 1400304 The Princeton University Plasma Physics Laboratory (PPPL), 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.


401

Sample SULI Program Student Work | Princeton Plasma Physics Lab  

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

Sample SULI Program Student Work 2014 Implementation of remote capabilities for the planeterrella experiment at the Princeton Plasma Physics Laboratory, Adrianna Angulo, Florida...

402

Other Physics and Engineering Research | Princeton Plasma Physics...  

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

into the formation of the early universe. Developing Medical Isotopes Researchers at the Princeton Plasma Physics Laboratory are using their knowledge of fusion to develop a...

403

Microinstabilities in weak density gradient tokamak systems  

SciTech Connect (OSTI)

A prominent characteristic of auxiliary-heated tokamak discharges which exhibit improved (''H-mode type'') confinement properties is that their density profiles tend to be much flatter over most of the plasma radius. Depsite this favorable trend, it is emphasized here that, even in the limit of zero density gradient, low-frequency microinstabilities can persist due to the nonzero temperature gradient.

Tang, W.M.; Rewoldt, G.; Chen, L.

1986-04-01T23:59:59.000Z

404

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

405

Forest fire near Los Alamos National Laboratory  

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

Forest fire near Los Alamos National Laboratory Forest fire near Los Alamos National Laboratory Forest fire near Los Alamos National Laboratory The Las Conchas fire burning in the Jemez Mountains approximately 12 miles southwest of the boundary of LANL has not entered Lab property at this time. June 26, 2011 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 innovation covering multi-disciplines from bioscience, sustainable energy sources, 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 innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new materials.

406

Arbitrary amplitude solitary and shock waves in an unmagnetized quantum dusty electron-positron-ion plasma  

SciTech Connect (OSTI)

The behavior of quantum dust ion acoustic soliton and shocks in a plasma including inertialess quantum electrons and positrons, classical cold ions, and stationary negative dust grains are studied, using arbitrary amplitude approach. The effect of dissipation due to viscosity of ions is taken into account. The numerical analysis of Sagdeev potential for small value of quantum diffraction parameter (H) shows that for chosen plasma, only compressive solitons can exist and the existence domain of this type of solitons is decreased by increasing dust density (d). Additionally, the possibility of propagation of both subsonic and supersonic compressive solitons is investigated. It is shown that there is a critical dust density above which only supersonic solitons are observed. Moreover, increasing d leads to a reduction in the existence domain of compressive solitons and the possibility of propagation of rarefactive soliton is provided. So, rarefactive solitons are observed only due to the presence of dust particles in this model quantum plasma. Furthermore, numerical solution of governed equations for arbitrary amplitude shock waves has been investigated. It is shown that only compressive large amplitude shocks can propagate. Finally, the effects of plasma parameters on these structures are investigated. This research will be helpful in understanding the properties of dense astrophysical (i.e., white dwarfs and neutron stars) and laboratory dusty plasmas.

Rouhani, M. R.; Akbarian, A.; Mohammadi, Z. [Department of Physics, Alzahra University, P. O. Box 1993891176, Tehran (Iran, Islamic Republic of)] [Department of Physics, Alzahra University, P. O. Box 1993891176, Tehran (Iran, Islamic Republic of)

2013-08-15T23:59:59.000Z

407

National Laboratory  

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

Homesteading on the Pajarito Plateau Homesteading on the Pajarito Plateau topic of inaugural lecture at Los Alamos National Laboratory January 4, 2013 Lecture series begins yearlong commemoration of 70th anniversary LOS ALAMOS, NEW MEXICO, Jan. 3, 2013-In commemoration of its 70th anniversary, Los Alamos National Laboratory kicks off a yearlong lecture series on Wednesday, Jan. 9, at 5:30 p.m. with a presentation about homesteading on the Pajarito Plateau at the Bradbury Science Museum, 1350 Central Avenue, Los Alamos. - 2 - The inaugural lecture is based on a book by local writers Dorothy Hoard, Judy Machen and Ellen McGehee about the area's settlement between 1887 and 1942. On hikes across the Pajarito Plateau, Hoard envisioned the Los Alamos area before modern roads and bridges made transportation much easier. The trails she walked

408

Density dependence of reactor performance with thermal confinement scalings  

SciTech Connect (OSTI)

Energy confinement scalings for the thermal component of the plasma published thus far have a different dependence on plasma density and input power than do scalings for the total plasma energy. With such thermal scalings, reactor performance (measured by Q, the ratio of the fusion power to the sum of the ohmic and auxiliary input powers) worsens with increasing density. This dependence is the opposite of that found using scalings based on the total plasma energy, indicating that reactor operation concepts may need to be altered if this density dependence is confirmed in future research.

Stotler, D.P.

1992-03-01T23:59:59.000Z

409

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

410

Attenuation of Electromagnetic Waves by a Plasma Layer at Atmospheric Pressure  

Science Journals Connector (OSTI)

Plasma layers at atmospheric pressure, are good broad band absorbers of ... have to be optimized. These are the plasma number density, and the thickness of the plasma layer. It is found that in order ... an effec...

Mounir Laroussi; William T. Anderson

1998-03-01T23:59:59.000Z

411

3300 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 39, NO. 12, DECEMBER 2011 Direct-Coupled Plasma-Assisted Combustion  

E-Print Network [OSTI]

by coupling an atmospheric plasma dis- charge to a premixed methane/air flame. The absorbed microwave power3300 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 39, NO. 12, DECEMBER 2011 Direct-Coupled Plasma were observed as power increased. In the plasma-coupled pre- mixed flame, OH number densities, which

Lee, Tonghun

412

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

E-Print Network [OSTI]

densities greater than 1015 cm-3 , the penetration rate of the field into the plasma by Hall mechanisms of the magnetic field front and the heavier-ion plasma is penetrated by the field. Species-separation effects may to be characterized by fast magnetic field (current) penetration into the plasma.9­11 In recent experiments

413

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

414

Surface modification with a remote atmospheric pressure plasma  

Science Journals Connector (OSTI)

A remote atmospheric pressure DC glow discharge is used for the treatment of polymer foils. The envisaged plasma effect is an increase in the surface ... the distribution of the current density in the plasma. The...

E. Temmerman; C. Leys

2004-03-01T23:59:59.000Z

415

Properties of Ion Beams Generated by Nitrogen Plasma Focus  

Science Journals Connector (OSTI)

Numerical experiments have been systematically carried out using the modified Lee model code on various plasma focus devices operated with nitrogen gas. The ion ... flow density, and damage factor) of the plasma focus

M. Akel; S. Alsheikh Salo; S. H. Saw; S. Lee

2014-04-01T23:59:59.000Z

416

Time-Dependent Integrated Modeling of Burning Plasmas R. Budny, R. Andre, and C. Kessel (PPPL)  

E-Print Network [OSTI]

. Will need to certify each plasma before it is tried PRINCETON PLASMA PHYSICS LABORATORY PPPL 1 #12;Overview simulations of energy, momentum, and particle flows 4. estimates of alpha ash profile PRINCETON PLASMA PHYSICS, ECH/ECCD Advanced heating/CD codes Advanced predictive codes plasma, current profiles PRINCETON PLASMA

417

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

418

Progress on Plasma Lens Experiment at the Final Focus Test Beam *  

E-Print Network [OSTI]

of the experiment are to study plasma focusing of high energy, high density particle beams; to investigate plasma colliders. INTRODUCTION Plasma focusing devices are compact, simple, and very strong focusing elements­of­principle experiments using low density particle beams have demonstrated plasma focusing (10­ 12). Our goal

419

Elena Belova | Princeton Plasma Physics Lab  

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

Elena Belova Elena Belova Principal Research Physicist, Plasma Physics Laboratory. Elena V. Belova is a Principal Research Physicist at the Princeton University Plasma Physics Laboratory. Her research interests include: kinetic effects on the MHD stability; interaction of energetic particles with MHD waves; global stability of the Field-Reversed Configurations; numerical simulations, and fluid/kinetic(gyro-kinetic) hybrid models of plasmas. She received a M.S. in physics from Moscow Institute of Physics and Technology (Russia), and worked at the Space Research Institute in Moscow, Russia till 1992. She received a Ph. D. in plasma physics from Dartmouth College, Hanover NH in 1997. Following a three year post doctoral position with Princeton Plasma Physics Laboratory, she joined PPPL staff in

420

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

2006-05-21T23:59:59.000Z

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.


421

Princeton Plasma Physics Lab - NSTX-U  

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

certified safe to operate. At the U.S. Department of Energy's (DOE) Princeton Plasma Physics Laboratory (PPPL), the task of evaluating the safety of the 94 million upgrade...

422

Visiting PPPL | Princeton Plasma Physics Lab  

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

Fusion Basics DOE and Fusion Links Contract Documents Speakers Bureau Tours Visiting PPPL Princeton Plasma Physics Laboratory P.O. Box 451 Princeton, NJ 08543-0451 GPS: 100...

423

Contact Information | Princeton Plasma Physics Lab  

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

Contact Information Princeton Plasma Physics Laboratory P.O. Box 451 Princeton, NJ 08543-0451 GPS: 100 Stellarator Road Princeton, NJ 08540 U.S.A. Main Telephone: (609) 243-2000...

424

News Archive | Princeton Plasma Physics Lab  

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

With the click of a computer mouse, a scientist at the U.S. Department of Energy's Princeton Plasma Physics Laboratory (PPPL) sends 10,000 volts of electricity into a...

425

Contract Documents | Princeton Plasma Physics Lab  

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

between Princeton University and the U.S. Department of Energy for operating the Princeton Plasma Physics Laboratory. Associated Files: Contract No. DE-AC02-09CH11466,...

426

Open House | Princeton Plasma Physics Lab  

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

Contact Us Open House PPPL Open House Saturday, June 1 9 a.m. to 4 p.m. Princeton Plasma Physics Laboratory 100 Stellarator Road Princeton, NJ, 08540 OPEN HOUSE PROGRAM BOOKLET...

427

PPPL Technical Reports | Princeton Plasma Physics Lab  

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

Phone: (609) 243-2245 Fax: (609) 243-2751 Mailing Address: Publications and Reports Princeton Plasma Physics Laboratory P.O. Box 451 MS 40 Princeton, NJ 08543 USA...

428

Michael C Zarnstorff | Princeton Plasma Physics Lab  

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

said Zarnstorff, an award-winning physicist who joined the U.S. Department of Energy's Princeton Plasma Physics Laboratory (PPPL) in 1984, and has been deputy director for...

429

Stewart Prager | Princeton Plasma Physics Lab  

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

the 60-mile trip from his childhood home in the Bronx to the U.S. Department of Energy's Princeton Plasma Physics Laboratory (PPPL), which he now directs. Along the way came...

430

News Archive | Princeton Plasma Physics Lab  

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

energy - the process that powers the sun and other stars. The U.S. Department of Energy's Princeton Plasma Physics Laboratory (PPPL) will host an Open House on Saturday, May 1,...

431

Google:[Leonid Zakharov] http://w3.pppl.gov/~zakharov Where is the edge in toroidal plasmas ?1  

E-Print Network [OSTI]

Leonid E. Zakharov Princeton Plasma Physics Laboratory, MS-27 P.O. Box 451, Princeton NJ 08543­AC020­76­CHO­3073. PRINCETON PLASMA PHYSICS LABORATORY PPPL #12;Contents 1 What is the plasma edge 4 2 is the plasma edge 27 6 Summary. 32 Leonid E. Zakharov, Experimental Seminar, PPPL April 15, 2008, Princeton NJ

Zakharov, Leonid E.

432

Sandia National Laboratories: Advanced Materials Laboratory  

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

Advanced Materials Laboratory Sandia Researchers Win CSP:ELEMENTS Funding Award On June 4, 2014, in Advanced Materials Laboratory, Concentrating Solar Power, Energy, Energy...

433

Two-dimensional Vlasov solution for a collisionless plasma jet across transverse magnetic field lines with a sheared bulk velocity  

Science Journals Connector (OSTI)

We consider a two-dimensional (2D) stationary stream of a collisionless plasma injected across an external stationary magnetic field and a background stagnant plasma. The solution is found by solving the Vlasov equation for each species (electrons and protons), the Maxwell-Ampere equation for the magnetic vector potential, and the equation of plasma quasineutrality for the electrostatic potential. The solution of the stationary Vlasov equation is given in terms of two constants of motion and one adiabatic invariant. The partial charge and current densities are given by analytical expressions of the moments of the velocity distribution functions for each particle species. The 2D distribution of the plasma bulk velocity, Vx(y,z), is roughly uniform inside the jet. There is no plasma bulk flow in the direction of the magnetic field. Inside the boundary layer interfacing the jet and the stagnant plasma, the bulk velocity has gradients (i.e., shears) in the direction parallel as well perpendicular to the magnetic field. The parallel component of this gradient, ??V?, produces a nonzero electric field component parallel to the magnetic field lines, E?B?0. The parallel electric field within the transition layer is a basic element allowing plasma elements to be transported across magnetic field lines in astrophysical systems as well as in laboratory experiments where plasmoids are injected across magnetic fields.

Marius M. Echim and Joseph F. Lemaire

2005-09-13T23:59:59.000Z

434

Neutrino oscillations in a turbulent plasma  

SciTech Connect (OSTI)

A new model for the joint neutrino flavor and plasma oscillations is introduced, in terms of the dynamics of the neutrino flavor polarization vector in a plasma background. Fundamental solutions are found for both time-invariant and time-dependent media, considering slow and fast variations of the electron plasma density. The model is shown to be described by a generalized Hamiltonian formalism. In the case of a broad spectrum of electron plasma waves, a statistical approach indicates the shift of both equilibrium value and frequency oscillation of flavor coherence, due to the existence of a turbulent plasma background.

Mendonça, J. T. [Instituto de Física, Universidade de São Paulo, São Paulo, SP, CEP 05508-090 Brazil and IPFN, Instituto Superior Técnico, 1049-001 Lisboa (Portugal)] [Instituto de Física, Universidade de São Paulo, São Paulo, SP, CEP 05508-090 Brazil and IPFN, Instituto Superior Técnico, 1049-001 Lisboa (Portugal); Haas, F. [Departamento de Física, Universidade Federal do Paraná, Curitiba PR, CEP 81531-990 (Brazil)] [Departamento de Física, Universidade Federal do Paraná, Curitiba PR, CEP 81531-990 (Brazil)

2013-07-15T23:59:59.000Z

435

Plasma physics: A promising advance in nuclear fusion  

Science Journals Connector (OSTI)

... Formidable challenges face the decades-long quest to achieve nuclear fusion— the power source of stars — in the laboratory. For a plasma to ... power source of stars — in the laboratory. For a plasma to undergo self-heating nuclear fusion (ignition), it must be both hot and well confined. The facilities that hope ...

Mark Herrmann

2014-02-12T23:59:59.000Z

436

Plasma Physics  

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

of light years can emerge from the frenetic motion of plasmas. A team of Lawrence Livermore researchers has discovered that supersonic counter-streaming (directed at each...

437

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

438

VISUALIZATION OF MAGNETICALLY CONFINED PLASMAS  

E-Print Network [OSTI]

developments in experimental and theoretical fu- sion energy research towards more geometric details such a source of energy is the mission of the fusion energy research community. There is presently a great, Princeton Plasma Physics Laboratory Princeton NJ 08543, USA November 30, 1999 Abstract With the rapid

439

Numerical Study of Radiation Emission from the Argon Plasma Focus  

Science Journals Connector (OSTI)

Ion populations and emitted spectrum of argon plasma have been calculated using the POPULATE and SPECTRA codes of the RATION suite at different conditions (electron temperatures, electron densities, ion densities...

M. Akel; S. Alsheikh Salo; C. S. Wong

2013-04-01T23:59:59.000Z

440

Sensitivity to Error Fields in NSTX High Beta Plasmas  

SciTech Connect (OSTI)

It was found that error field threshold decreases for high ? in NSTX, although the density correlation in conventional threshold scaling implies the threshold would increase since higher ? plasmas in our study have higher plasma density. This greater sensitivity to error field in higher ? plasmas is due to error field amplification by plasmas. When the effect of amplification is included with ideal plasma response calculations, the conventional density correlation can be restored and threshold scaling becomes more consistent with low ? plasmas. However, it was also found that the threshold can be significantly changed depending on plasma rotation. When plasma rotation was reduced by non-resonant magnetic braking, the further increase of sensitivity to error field was observed.

Jong-Kyu Park, Jonathan E. Menard, Stefan P. Gerhardt, Richard J. Buttery, Steve A. Sabbagh, Ronald E. Bell and Benoit P. LeBlanc

2011-11-07T23:59:59.000Z

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

Plasma-parameter measurements using neutral-particle-beam attenuation  

SciTech Connect (OSTI)

Intense and energetic neutral-particle-beam injection used for fueling or heating magnetically confined, controlled-fusion experimental plasmas can also provide diagnostic measurements of the plasmas. The attenuation of an atomic beam (mainly from charge-exchange and ionization interactions) when passing through a plasma gives the plasma line density. Orthogonal arrays of highly collimated detectors of the secondary-electron-emission type have been used in magnetic-mirror experiments to measure neutral-beam attenuation along chords through the plasma volume at different radial and axial positions. The radial array is used to infer the radial plasma-density profile; the axial array, to infer the axial plasma-density profile and the ion angular distribution at the plasma midplane.

Foote, J.H.; Molvik, A.W.; Turner, W.C.

1982-07-07T23:59:59.000Z

442

Emission of Radio-Frequency Waves from Plasmas  

Science Journals Connector (OSTI)

Observations of the radio-frequency emission from extraterrestrial plasmas and plasmas produced in the laboratory are described and various attempts at interpretation of the results are reviewed. Estimates are made of the probable loss of radiant energy from plasmas in proposed thermonuclear reactors.

G. Bekefi; Sanborn C. Brown

1961-01-01T23:59:59.000Z

443

Plasma detachment and momentum transfer in magnetic nozzles  

E-Print Network [OSTI]

Electric Propulsion and Plasma Dynamics Laboratory, Princeton University, Princeton, NJ, 08544 The naturePlasma detachment and momentum transfer in magnetic nozzles Justin M. Little and Edgar Y. Choueiri the interaction of the magnetic field induced by the currents in the plasma with the current in the applied field

Choueiri, Edgar

444

Lawrence Livermore National Laboratory  

Broader source: Energy.gov [DOE]

Lawrence Livermore National Laboratory’s (LLNL) primary mission is research and development in support of national security.

445

Sandia National Laboratories: photovoltaic  

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

PV Facilities On November 10, 2010, in Photovoltaic System Evaluation Laboratory Distributed Energy Technologies Laboratory Microsystems and Engineering Sciences Applications...

446

Facilities | Argonne National Laboratory  

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

Engineering Research Facility Distributed Energy Research Center Engine Research Facility Heat Transfer Laboratory Tribology Laboratory Transportation Beamline at the Advanced...

447

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

448

Plasma Radiation  

Science Journals Connector (OSTI)

... JUST over ten years ago the first book on plasma physics as a subject in its own right appeared; in a gradually swelling stream ... been surprisingly few monographs. One topic which has had scant coverage in any form is plasma radiation (except for spectral-line radiation which has been dealt with very fully in ...

T. J. M. BOYD

1967-07-01T23:59:59.000Z

449

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

450

Plasma Sources Science and Technology Plasma Sources Sci. Technol. 23 (2014) 044005 (6pp) doi:10.1088/0963-0252/23/4/044005  

E-Print Network [OSTI]

and Nathaniel J Fisch Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey, 08543Plasma Sources Science and Technology Plasma Sources Sci. Technol. 23 (2014) 044005 (6pp) doi:10.1088/0963-0252/23/4/044005 Cross-field plasma lens for focusing of the Hall thruster plume Martin E Griswold, Yevgeny Raitses

451

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

452

Alternating fluxes of positive and negative ions from an ionion plasma Sivananda K. Kanakasabapathya)  

E-Print Network [OSTI]

Alternating fluxes of positive and negative ions from an ion­ion plasma Sivananda K. Kanakasabapathya) and Lawrence J. Overzet Plasma Applications Laboratory, Erik Jonsson School of Engineering and Demetre Economou Plasma Processing Laboratory, Department of Chemical Engineering, University of Houston

Economou, Demetre J.

453

Design of a Microwave-Initiated Pulsed Plasma Thruster Jian F. Li, Class of 2006  

E-Print Network [OSTI]

and departments: · Prof. Edgar Choueiri of the Princeton University Electric Propulsion and Plasma Dynamics and Plasma Dynamics Laboratory. · Prof. Miles and Princeton Applied Physics Group for microwave leak detector of the Princeton University Electric Propulsion and Plasma Dynamics Laboratory for his insight into microwave

Choueiri, Edgar

454

Plasma diagnostics for the sustained spheromak physics experiment  

Science Journals Connector (OSTI)

In this article we present an overview of the plasma diagnostics operating or planned for the sustained spheromak physics experiment device now operating at Lawrence Livermore National Laboratory. A set of 46 wall-mounted magnetic probes provide the essential data necessary for magnetic reconstruction of the Taylor relaxed state. Rogowski coils measure currents induced in the flux conserver. A CO 2 laser interferometer is used to measure electron line density. Spectroscopic measurements include an absolutely-calibrated spectrometer recording extended domain spectrometer for obtaining time-integrated visible ultraviolet spectra and two time-resolved vacuum monochrometers for studying the time evolution of two separate emission lines. Another time-integrated spectrometer records spectra in the visible range. Filtered silicon photodiode bolometers provide total power measurements and a 16 channel photodiode spatial array gives radial emission profiles. Two-dimensional imaging of the plasma and helicity injector is provided by gated television cameras and associated image-processing software. An array of fiber-coupled photodetectors with H alpha filters view across the midplane and in the injector region to measure neutral hydrogen concentrations. Several novel diagnostics are being fielded including a transient internal probe (TIP) and an ultrashort-pulse reflectometer (USPR) microwave reflectometer. The TIP probe fires a very high velocity optical bullet through the plasma and will provide fairly nonpertabative internal magnetic field and current measurements to compare with an equilibrium code model fitted to wall-mounted probes. The USPR is being designed to study edge density and turbulent fluctuations. A multipoint Thomson scattering system is currently being installed to give radial temperature and density profiles.

H. S. McLean; A. Ahmed; D. Buchenauer; D. Den Hartog; C. W. Domier; D. N. Hill; C. Holcomb; E. B. Hooper; E. C. Morse; M. Nagata; Y. Roh; B. Stallard; R. D. Wood; S. Woodruff; G. Wurden; Z. Wang; SSPX Team

2001-01-01T23:59:59.000Z

455

Voyager 2 Plasma Wave Observations at Saturn  

Science Journals Connector (OSTI)

...on the basis of plasma probe data) and infer...the weak 3.25-kHz waves represent electro-magnetic...pitch-angle dif-fusion and atmospheric precipitation, but for this low plasma density and high magnetic...f = 0.8 to 1.3 kHz) and a structured...

F. L. SCARF; D. A. GURNETT; W. S. KURTH; R. L. POYNTER

1982-01-29T23:59:59.000Z

456

Electron Plasmas in a Magnetic Mirror  

E-Print Network [OSTI]

scale with the magnetic field strength; the electrostatic potential varies along the field lines to make this density variation possible. Further, the plasma profile does not follow the magnetic field lines proportional to magnetic field. · Potential varies along field lines. · Outer plasma radius necks down more

Wurtele, Jonathan

457

Physics of Laser-driven plasma-based acceleration  

SciTech Connect (OSTI)

The physics of plasma-based accelerators driven by short-pulse lasers is reviewed. This includes the laser wake-field accelerator, the plasma beat wave accelerator, the self-modulated laser wake-field accelerator, and plasma waves driven by multiple laser pulses. The properties of linear and nonlinear plasma waves are discussed, as well as electron acceleration in plasma waves. Methods for injecting and trapping plasma electrons in plasma waves are also discussed. Limits to the electron energy gain are summarized, including laser pulse direction, electron dephasing, laser pulse energy depletion, as well as beam loading limitations. The basic physics of laser pulse evolution in underdense plasmas is also reviewed. This includes the propagation, self-focusing, and guiding of laser pulses in uniform plasmas and plasmas with preformed density channels. Instabilities relevant to intense short-pulse laser-plasma interactions, such as Raman, self-modulation, and hose instabilities, are discussed. Recent experimental results are summarized.

Esarey, Eric; Schroeder, Carl B.

2003-06-30T23:59:59.000Z

458

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

459

ANL/ALCF/ESP-13/15 Global Simulation of Plasma Microturbulence at the  

E-Print Network [OSTI]

Computing Facility #12;About Argonne National Laboratory Argonne is a U.S. Department of Energy laboratory lines, toward the outside of the plasma, where it is lost. Loss of plasma and energy, of course, works managed by UChicago Argonne, LLC under contract DE-AC02-06CH11357. The Laboratory's main facility

Kemner, Ken

460

Plasma catalytic reforming of methane  

Science Journals Connector (OSTI)

Thermal plasma technology can be efficiently used in the production of hydrogen and hydrogen-rich gases from methane and a variety of fuels. This article describes progress in plasma reforming experiments and calculations of high temperature conversion of methane using heterogeneous processes. The thermal plasma is a highly energetic state of matter that is characterized by extremely high temperatures (several thousand degrees Celsius), and a high degree of dissociation and a substantial degree of ionization. The high temperatures accelerate the reactions involved in the reforming process. Hydrogen-rich gas (40% H2, 17% CO2 and 33% N2, for partial oxidation/water shifting) can be efficiently made in compact plasma reformers. Experiments have been carried out in a small device (2–3 kW) and without the use of efficient heat regeneration. For partial oxidation/water shifting, it was determined that the specific energy consumption in the plasma reforming processes is 16 MJ/kg H2 with high conversion efficiencies. Larger plasmatrons, better reactor thermal insulation, efficient heat regeneration and improved plasma catalysis could also play a major role in specific energy consumption reduction and increasing the methane conversion. A system has been demonstrated for hydrogen production with low CO content (?1.5%) with power densities of ?30 kW (H2 HHV)/l of reactor, or ?10 m3/h H2 per liter of reactor. Power density should further increase with increased power and improved design.

L Bromberg; D.R Cohn; A Rabinovich; N Alexeev

1999-01-01T23:59:59.000Z

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.


461

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

462

Origin of Tokamak Density Limit Scalings  

Science Journals Connector (OSTI)

The onset criterion for radiation driven islands [P.?H. Rebut and M. Hugon, Plasma Physics and Controlled Nuclear Fusion Research 1984: Proc. 10th Int. Conf. London, 1984, (IAEA, Vienna, 1985), Vol. 2] in combination with a simple cylindrical model of tokamak current channel behavior is consistent with the empirical scaling of the tokamak density limit [M. Greenwald, Nucl. Fusion 28, 2199 (1988)]. Many other unexplained phenomena at the density limit are consistent with this novel physics mechanism.

D. A. Gates and L. Delgado-Aparicio

2012-04-20T23:59:59.000Z

463

Plasma temperatures in Saturn's ionosphere Luke Moore,1  

E-Print Network [OSTI]

Plasma temperatures in Saturn's ionosphere Luke Moore,1 Marina Galand,2 Ingo Mueller-Wodarg,2 Roger the height of peak electron density, while they can reach 500 K during the day at the topside. Plasma scale of Saturn have been used to estimate plasma temperature as a comparison. Such an estimate agrees well

Mendillo, Michael

464

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

465

Clustered gases as a medium for efficient plasma waveguide generation  

Science Journals Connector (OSTI)

...on-axis density of a plasma waveguide is determined...or Bessel beam) line focus breakdown of a gas using...heater of the cluster plasma despite the fact that...a Bessel-beam line focus breakdown in an elongated...axicon which heat the plasma and are transmitted through...

2006-01-01T23:59:59.000Z

466

Opportunities with Laboratories under the Chicago Office  

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

Opportunities with Opportunities with 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. Engineering Support Services; Charles Neumyer; $1,417,116 4. Conceptual design of New PS&T Building; Shawn Connolly; $500,000 Lawrence Berkeley National Laboratory (LBL) 1. Software Maintenance and support for ALS software; 9/30/2011; $556,000 (Biointuition) 2. Consulting services to conduct a hazard survey; 9/30/11; $549,000 (Alphatrac, Inc.) 3. Analytical Laboratory services; 7/31/11; $465,000 (BC Laboratories, Inc.) LBL Continued.... 4. Blanket Order to provide photo artwork; 9/30/2011; $460,000 (CMP) 5. Pick-up and delivery courier servicces for as- needed services; 5/31/2011; $250,000 (IDS

467

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

468

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

469

Ames Laboratory Logos | The Ames Laboratory  

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

Ames Laboratory Logos The Ames Laboratory Logo comes in several formats. EPS files are vector graphics created in Adobe Illustrator and saved with a tiff preview so they will...

470

Laboratory awards subcontracts to small businesses  

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

Subcontracts awarded to small businesses Subcontracts awarded to small businesses Laboratory awards subcontracts to small businesses A company owned and operated by Ohkay Owingeh Pueblo will soon be providing custodial support services to the Lab. October 15, 2008 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 innovation covering multi-disciplines from bioscience, sustainable energy sources, 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 innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new materials. Contact Steve Sandoval

471

Los Alamos National Laboratory sponsors Hazmat Challenge  

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

Hazmat Challenge Hazmat Challenge Los Alamos National Laboratory sponsors Hazmat Challenge The challenge provides hazardous materials responders the opportunity to network and learn new techniques under realistic conditions in a safe environment. July 27, 2009 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 innovation covering multi-disciplines from bioscience, sustainable energy sources, 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 innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new materials.

472

Los Alamos National Laboratory names cleanup subcontractors  

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

Cleanup subcontractors named Cleanup subcontractors named Los Alamos National Laboratory names cleanup subcontractors The three companies are Los Alamos Technical Associates (LATA), Portage Inc., and ARSEC Environmental, LLC (ARSEC). August 14, 2009 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 innovation covering multi-disciplines from bioscience, sustainable energy sources, 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 innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new materials. Contact Fred deSousa

473

Laboratory awards final Recovery Act demolition contracts  

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

Recovery Act demolition contracts Recovery Act demolition contracts Laboratory awards final Recovery Act demolition contracts The two winning bidders will each demolish a portion of the remaining unused buildings at the Lab's historic Technical Area 21. April 20, 2010 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 innovation covering multi-disciplines from bioscience, sustainable energy sources, 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 innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new materials.

474

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.

475

APPLICATION OF A NEW ALGORITHM TO PLASMA SHAPE CONTROL IN BPX  

E-Print Network [OSTI]

.C. JARDIN (Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey, United StatesLETTERS APPLICATION OF A NEW ALGORITHM TO PLASMA SHAPE CONTROL IN BPX F. HOFMANN", N. POMPHREY, S discharge in the Burning Plasma Experiment (BPX), using the TSC code. The algorithm controls the plasma

476

RF Plasma Cathode-Neutralizer for Space Applications IEPC-2007-266  

E-Print Network [OSTI]

Raitses and Nathaniel J. Fisch Princeton Plasma Physics Laboratory, Princeton, NJ 08543, USA AbstractRF Plasma Cathode-Neutralizer for Space Applications IEPC-2007-266 Presented at the 30th: A new plasma cathode-neutralizer based on electron extraction from inductively coupled plasma (ICP

477

Operation of ferroelectric plasma sources in a gas discharge modea... A. Dunaevskyb)  

E-Print Network [OSTI]

. Fisch Princeton Plasma Physics Laboratory, Princeton University, P.O. Box 451, Princeton, New JerseyOperation of ferroelectric plasma sources in a gas discharge modea... A. Dunaevskyb) and N. J plasma sources in vacuum are known as sources of ablative plasma, formed due to surface discharge

478

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...

479

High Energy Density Science with High Peak Power Light Sources  

Science Journals Connector (OSTI)

High energy density (HED) science is a growing sub-field of plasma and condensed matter physics. I will examine how recent technological developments in high peak power, petawatt-class...

Ditmire, Todd

480

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

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.


481

Dynamical Plasma Response during Driven Magnetic Reconnection J Egedal,* A Fasoli,  

E-Print Network [OSTI]

Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02139 in association with reconnection phenomena [1] both in space and laboratory plasmas, e.g., in solar flares [2

Egedal, Jan

482

Dynamical Plasma Response during Driven Magnetic Reconnection J Egedal, * A Fasoli, + and J Nazemi  

E-Print Network [OSTI]

Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02139 in association with reconnection phenomena [1] both in space and laboratory plasmas, e.g., in solar flares [2

Egedal, Jan

483

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

484

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

485

On the feasibility of electron cyclotron heating of overcritical plasma in a magnetic mirror trap  

SciTech Connect (OSTI)

The feasibility of matching electromagnetic radiation in the electron cyclotron frequency range to a dense plasma in an open magnetic trap by producing an inverted (with a minimum on the axis) plasma density profile is discussed. The use of such a profile shows promise for the implementation of efficient cyclotron heating at plasma densities above the critical density, at which the Langmuir frequency is equal to the heating radiation frequency. Examples of the magnetic field and plasma density distributions in a mirror trap are presented for which analysis of the beam trajectories shows the feasibility of efficient electron cyclotron absorption of microwave beams in overcritical plasma.

Vodopyanov, A. V.; Golubev, S. V.; Gospodchikov, E. D.; Smolyakova, O. B.; Suvorov, E. V. [Russian Academy of Sciences, Institute of Applied Physics (Russian Federation)

2012-06-15T23:59:59.000Z

486

Laboratory Equipment & Supplies | Sample Preparation Laboratories  

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

Equipment & Supplies Equipment & Supplies John Bargar, SSRL Scientist Equipment is available to serve disciplines from biology to material science. All laboratories contain the following standard laboratory equipment: pH meters with standard buffers, analytical balances, microcentrifuges, vortex mixers, ultrasonic cleaning baths, magnetic stirrers, hot plates, and glassware. Most laboratories offer ice machines and cold rooms. Specialty storage areas for samples include a -80 freezer, argon and nitrogen glove boxes, radiation contamination areas, inert atmosphere chambers, and cold rooms. For specific information please see: Equipment Inventory Checkout Equipment & Supplies To view equipment inventory by laboratory, refer to the following pages: Biology Chemistry & Material Science Laboratory 1 Inventory

487

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

488

Dense plasma properties from shock wave experiments  

Science Journals Connector (OSTI)

A review is presented of the novel experimental results of investigation of physical properties of the coupled dense plasmas generated as a result of shock compression up to megabar pressure range. High-energy plasma states were generated by single and multiple shock compression. The highly time-resolved diagnostics permit us to measure thermodynamical, electrophysical and optical properties of high pressure condensed plasmas in the broad phase diagram region—from the compressed condensed solid state up to the low density gas range, including strongly coupled plasma and metal–insulator transition regions.

V B Mintsev; V E Fortov

2006-01-01T23:59:59.000Z

489

History by The Department of Energy's Other Major Laboratories and  

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

BY THE BY THE DEPARTMENT OF ENERGY'S Other Major Laboratories and Facilities Ames Laboratory Ames Laboratory-Shaping Science for 60 Years A History of Innovation Ames Achievements Listing of Major Labs and Facilities Top The New Brunswick Laboratory (NBL) History New Brunswick Lab Marks Its 50th Anniversary NBL Achievements Listing of Major Labs and Facilities Top Oak Ridge Institute for Science and Education (ORISE) About ORISE: Message from the Director Oak Ridge Institute for Science and Education ORISE Achievements Listing of Major Labs and Facilities Top Princeton Plasma Physics Laboratory (PPPL) History of the PPPL History of the Harold P. Furth Plasma Physics Library PPPL Achievements Listing of Major Labs and Facilities Top Savannah River Ecology Laboratory (SREL)

490

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

491

E-Print Network 3.0 - atomic vapor density Sample Search Results  

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

T is temperature, Qris... F, is magnetic force, J is vapor plasma current density, c is speed of light, and B is magnetic flux... density. The induced magnetic force will act as...

492

Characteristics of plasma properties in an ablative pulsed plasma thruster  

SciTech Connect (OSTI)

Pulsed plasma thrusters are electric space propulsion devices which create a highly transient plasma bulk in a short-time arc discharge that is expelled to create thrust. The transitional character and the dependency on the discharge properties are yet to be elucidated. In this study, optical emission spectroscopy and Mach-Zehnder interferometry are applied to investigate the plasma properties in variation of time, space, and discharge energy. Electron temperature, electron density, and Knudsen numbers are derived for the plasma bulk and discussed. Temperatures were found to be in the order of 1.7 to 3.1 eV, whereas electron densities showed maximum values of more than 10{sup 17} cm{sup -3}. Both values showed strong dependency on the discharge voltage and were typically higher closer to the electrodes. Capacitance and time showed less influence. Knudsen numbers were derived to be in the order of 10{sup -3}-10{sup -2}, thus, indicating a continuum flow behavior in the main plasma bulk.

Schoenherr, Tony; Nees, Frank; Arakawa, Yoshihiro [Department of Aeronautics and Astronautics, University of Tokyo, Bunkyo, Tokyo 113-8656 (Japan); Komurasaki, Kimiya [Department of Advanced Energy, University of Tokyo, Kashiwa, Chiba 277-8561 (Japan); Herdrich, Georg [Institute of Space Systems (IRS), University of Stuttgart, 70569 Stuttgart, Baden-Wuerttemberg (Germany)

2013-03-15T23:59:59.000Z

493

News | Argonne National Laboratory  

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

News Argonne Laboratory Director Peter Littlewood (left) talks with a small business owner during the second annual "Doing Business with Argonne and Fermi National Laboratories"...

494

jevans | The Ames Laboratory  

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

jevans Ames Laboratory Profile James Evans Associate 315 Wilhelm Phone Number: 515-294-1638 Email Address: evans@ameslab.gov Ames Laboratory Associate and Professor, Iowa State...

495

Sustainability | The Ames Laboratory  

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

Sustainability Ames Laboratory is committed to environmental sustainability in all of its operations as outlined in the Laboratory's Site Sustainability Plan. Executive orders set...

496

Tokamak Equilibria with Reversed Current Density  

Science Journals Connector (OSTI)

Observations of nearly zero toroidal current in the central region of tokamaks (the “current hole”) raises the question of the existence of toroidal equilibria with very low or reversed current in the core. The solutions of the Grad-Shafranov equilibrium equation with hollow toroidal current density profile including negative current density in the plasma center are investigated. Solutions of the corresponding eigenvalue problem provide simple examples of such equilibrium configurations. More realistic equilibria with toroidal current density reversal are computed using a new equilibrium problem formulation and computational algorithm which do not assume nested magnetic surfaces.

A. A. Martynov; S. Yu. Medvedev; L. Villard

2003-08-21T23:59:59.000Z

497

Mini-conference on angular momentum transport in laboratory and naturea... Hantao Ji,1  

E-Print Network [OSTI]

and Astrophysical Plasmas 1 Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543-Madison, Madison, Wisconsin 53706, USA 4 Department of Astrophysical Sciences, Princeton University, Princeton, New by the Topical Group on Plasma Astrophysics, was held as part of the American Physical Society's Division

Ji, Hantao

498

ARGONNE NATIONAL LABORATORY 9700 South Cass Avenue  

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

LABORATORY LABORATORY 9700 South Cass Avenue Argonne, Illinois 60439 ______________ ANL/APS/TB-43 ______________ A New Approach to High-Current Operation of the Advanced Photon Source by G. K. Shenoy Experimental Facilities Division Advanced Photon Source April 2002 work sponsored by U.S. DEPARTMENT OF ENERGY Office of Science i Contents Abstract .............................................................................................................................1 1. Introduction...................................................................................................................2 2. Alternative Operational Parameters..............................................................................3 3. Undulator Tunability, Brilliance, Power, and Power Densities....................................5

499

The dynamics of variable-density turbulence  

SciTech Connect (OSTI)

The dynamics of variable-density turbulent fluids are studied by direct numerical simulation. The flow is incompressible so that acoustic waves are decoupled from the problem, and implying that density is not a thermodynamic variable. Changes in density occur due to molecular mixing. The velocity field, is in general, divergent. A pseudo-spectral numerical technique is used to solve the equations of motion. Three-dimensional simulations are performed using a grid size of 128{sup 3} grid points. Two types of problems are studied: (1) the decay of isotropic, variable-density turbulence, and (2) buoyancy-generated turbulence in a fluid with large density fluctuations. In the case of isotropic, variable-density turbulence, the overall statistical decay behavior, for the cases studied, is relatively unaffected by the presence of density variations when the initial density and velocity fields are statistically independent. The results for this case are in quantitative agreement with previous numerical and laboratory results. In this case, the initial density field has a bimodal probability density function (pdf) which evolves in time towards a Gaussian distribution. The pdf of the density field is symmetric about its mean value throughout its evolution. If the initial velocity and density fields are statistically dependent, however, the decay process is significantly affected by the density fluctuations. For the case of buoyancy-generated turbulence, variable-density departures from the Boussinesq approximation are studied. The results of the buoyancy-generated turbulence are compared with variable-density model predictions. Both a one-point (engineering) model and a two-point (spectral) model are tested against the numerical data. Some deficiencies in these variable-density models are discussed and modifications are suggested.

Sandoval, D.L.

1995-11-01T23:59:59.000Z

500

Magnetic fluctuations of a large nonuniform plasma column J. E. Maggsa)  

E-Print Network [OSTI]

Magnetic fluctuations of a large nonuniform plasma column J. E. Maggsa) and G. J. Morales Physics of spontaneously generated magnetic fluctuations in a large linear device in which the plasma density has different as at an interior plasma­plasma interface, thus phenomena of interest to magnetic fusion research as well

California at Los Angles, University of