Flows and Instabilities Associated with an Extremely Narrow Current Sheet Presented by Stephen Vincena April 20, 2004 University of Maryland Second Workshop.

Slides:

Advertisements

Similar presentations

Progress and Plans on Magnetic Reconnection for CMSO For NSF Site-Visit for CMSO May1-2, Experimental progress [M. Yamada] -Findings on two-fluid.

Advertisements

Anomalous Ion Heating Status and Research Plan

Particle acceleration in a turbulent electric field produced by 3D reconnection Marco Onofri University of Thessaloniki.

1 CENTER for EDGE PLASMA SCIENCES C E PS Status of Divertor Plasma Simulator – II (DiPS-II) 2 nd PMIF Workshop Sep. 19, 2011 Julich, Germany H.-J. Woo.

Electric Currents and Resistance II Physics 2415 Lecture 11 Michael Fowler, UVa.

William Daughton Plasma Physics Group, X-1 Los Alamos National Laboratory Presented at: Second Workshop on Thin Current Sheets University of Maryland April.

Electrical Techniques MSN506 notes. Electrical characterization Electronic properties of materials are closely related to the structure of the material.

Nonlinear Evolution of Whistler Turbulence W.A. Scales, J.J. Wang, and O. Chang Center of Space Science and Engineering Research Virginia Tech L. Rudakov,

Boundaries in the auroral region --- Small scale density cavities and associated processes --- Vincent Génot (CESR/CNRS) C. Chaston (SSL) P. Louarn (CESR/CNRS)

Observation and Theory of Substorm Onset C. Z. (Frank) Cheng (1,2), T. F. Chang (2), Sorin Zaharia (3), N. N. Gorelenkov (4) (1)Plasma and Space Science.

Nonresonant pitch angle scattering of electrons and breakdown of adiabatic invariance: Modeling Surja Sharma, Alexey Karavaev, Erin Lynch, Nail Gumerov,

Non-collisional ion heating and Magnetic Turbulence in MST Abdulgader Almagri On behalf of MST Team RFP Workshop Padova, Italy April 2010.

Parallel and Poloidal Sheared Flows close to Instability Threshold in the TJ-II Stellarator M. A. Pedrosa, C. Hidalgo, B. Gonçalves*, E. Ascasibar, T.

Electron interactions with CO 2 Bob Merlino Department of Physics and Astronomy The University of Iowa Iowa City, IA U. S. Department of Energy National.

Initial wave-field measurements in the Material Diagnostic Facility (MDF) Introduction : The Plasma Research Laboratory at the Australian National University.

Overview the CASTOR “Fast Particles” experiments A: F. Zacek 1, V. Petrzilka 1, M. Goniche 2, P. Devynck 2, J. Adamek 1 1 Association Euratom/IPP.CR, Za.

Edge Localized Modes propagation and fluctuations in the JET SOL region presented by Bruno Gonçalves EURATOM/IST, Portugal.

Review of Collaboration Activities J.Q. Dong* H.D. He, Y. Shen, and A.P. Sun Southwestern Institute of Physics, China *Institute for Fusion Theory and.

Dynamics of the breakdown of the discharge gap at high overvoltage A. Shvydky (University of Toledo, OH), V.N. Khudik (Plasma Dynamics Corp., OH), V.P.

Correlation Analysis of Electrostatic Fluctuation between Central and End Cells in GAMMA 10 Y. Miyata, M. Yoshikawa, F. Yaguchi, M. Ichimura, T. Murakami.

ECE & TCOM 590 Microwave Transmission for Telecommunications Introduction to Microwaves January 29, 2004.

Copyright © 2009 Pearson Education, Inc. Applications: Motors, Loudspeakers, Galvanometers.

N. Yugami, Utsunomiya University, Japan Generation of Short Electromagnetic Wave via Laser Plasma Interaction Experiments US-Japan Workshop on Heavy Ion.

Spatially Resolved Study of Inter-Cusp Transport and Containment of Primary Electrons Aimee A. Hubble a, John E. Foster b a) University of Michigan, Department.

Large-Amplitude Electric Fields Associated with Bursty Bulk Flow Braking in the Earth’s Plasma Sheet R. E. Ergun et al., JGR (2014) Speaker: Zhao Duo.

Recent experiments in the STOR-M Tokamak* Akira Hirose In collaboration with: C. Boucher (INRS-EMT), G. St. Germaine D. Liu, S. Livingstone, A. Singh,

Reconnection rates in Hall MHD and Collisionless plasmas

Laser-Induced Fluorescence for Plasma Diagnostics Designing and Testing an Optical Probe for Advanced Plasma Studies Stephanie Sears Advisor: Dr. Walter.

Two problems with gas discharges 1.Anomalous skin depth in ICPs 2.Electron diffusion across magnetic fields Problem 1: Density does not peak near the.

Nonlinear Optics in Plasmas. What is relativistic self-guiding? Ponderomotive self-channeling resulting from expulsion of electrons on axis Relativistic.

Probe measurements on the GOLEM tokamak Vojtech Svoboda 1, Miglena Dimitrova 2, Jan Stockel 1,2 1 Faculty of Nuclear Physics and Physical Engineering,

HT-7 ASIPP The Influence of Neutral Particles on Edge Turbulence and Confinement in the HT-7 Tokamak Mei Song, B. N. Wan, G. S. Xu, B. L. Ling, C. F. Li.

Laboratory Experiments on the interaction of electromagnetic waves at plasma gradients Walter Gekelman Pat Pribyl Yuhou Wang* * Left for position at LAM.

STUDIES OF NONLINEAR RESISTIVE AND EXTENDED MHD IN ADVANCED TOKAMAKS USING THE NIMROD CODE D. D. Schnack*, T. A. Gianakon**, S. E. Kruger*, and A. Tarditi*

A. Vaivads, M. André, S. Buchert, N. Cornilleau-Wehrlin, A. Eriksson, A. Fazakerley, Y. Khotyaintsev, B. Lavraud, C. Mouikis, T. Phan, B. N. Rogers, J.-E.

RFX-mod Program Workshop, Padova, January Current filaments in turbulent magnetized plasmas E. Martines.

Laboratory Study of Spiky Potential Structures Associated with Multi- Harmonic EIC Waves Robert L. Merlino and Su-Hyun Kim University of Iowa Guru Ganguli.

DEVELOPMENT OF ION ENERGY ANGULAR DISTRIBUTION THROUGH THE PRE-SHEATH AND SHEATH IN DUAL-FREQUENCY CAPACITIVELY COUPLED PLASMAS* Yiting Zhanga, Nathaniel.

FEC 2006 Reduction of Neoclassical Transport and Observation of a Fast Electron Driven Instability with Quasisymmetry in HSX J.M. Canik 1, D.L. Brower.

The CLIC accelerating structure development program Walter Wuensch CARE05 23 November 2005.

Multiscale Turbulence excited by a pulsed current sheet Walter Gekelman,Stephen Vincena, Patrick Pribyl, Brett Jacobs, Eric Lawrence (UCLA Department of.

Thursday, April 26, 2011 PHYS 1444 – Section 02 Lecture #21 Thursday April 28, 2011 Dr. Mark Sosebee for Dr. Andrew Brandt Maxwell Equations HW9 is due.

Monday, April 16, PHYS , Spring 2007 Dr. Andrew Brandt PHYS 1444 – Section 004 Lecture #21 Monday, April 30, 2007 Dr. Andrew Brandt Maxwell’s.

1 Observations of Linear and Nonlinear Dust Acoustic Waves* Bob Merlino, Jon Heinrich Su Hyun Kim and John Meyer Department of Physics and Astronomy The.

Large Area Plasma Processing System (LAPPS) R. F. Fernsler, W. M. Manheimer, R. A. Meger, D. P. Murphy, D. Leonhardt, R. E. Pechacek, S. G. Walton and.

1) For equivalent ECRH power, off-axis heating results in lower stored energy and lower core temperature 2) Plasma flow is significantly reduced with off-axis.

Measurements of Magnetic Fluctuations in HSX S. Oh, A.F. Almagri, D.T. Anderson, C. Deng, C. Lechte, K.M. Likin, J.N. Talmadge, J. Schmitt HSX Plasma Laboratory,

Helically Symmetry Configuration Evidence for Alfvénic Fluctuations in Quasi-Helically Symmetric HSX Plasmas C. Deng and D.L. Brower, University of California,

52nd Annual Meeting of the Division of Plasma Physics, November , 2010, Chicago, Illinois 5-pin Langmuir probe configured to measure floating potential.

53rd Annual Meeting of the Division of Plasma Physics, November , 2010, Salt Lake City, Utah 5-pin Langmuir probe configured to measure the Reynolds.

= Boozer g= 2*1e -7 *48*14*5361 =.7205 =0 in net current free stellarator, but not a tokamak. QHS Mirror Predicted Separatrix Position Measurements and.

Plasma Turbulence in the HSX Stellarator Experiment and Probes C. Lechte, W. Guttenfelder, K. Likin, J.N. Talmadge, D.T. Anderson HSX Plasma Laboratory,

Measurement of Electron Density Profile and Fluctuations on HSX C. Deng, D.L. Brower, W.X. Ding Electrical Engineering Department University of California,

Generation of anomalously energetic suprathermal electrons by an electron beam interacting with a nonuniform plasma Dmytro Sydorenko University of Alberta,

Electromagnetic Blood Flow Meters Measures instantaneous pulsatile flow of blood Works based on the principle of electromagnetic induction The voltage.

CHARACTERIZATION OF MICROWAVE DISCHARGE ION SOURCE FOR HIGH PROTON BEAM PRODUCTION IN CW AND PULSED MODE Rosalba Miracoli Consegna del premio “Francesco.

FEASIBILITY ANALYS OF AN MHD INDUCTIVE GENERATOR COUPLED WITH A THERMO - ACOUSTIC ENERGY CONVERSION SYSTEM S. Carcangiu 1, R. Forcinetti 1, A. Montisci.

Profiles of density fluctuations in frequency range of (20-110)kHz Core density fluctuations Parallel flow measured by CHERS Core Density Fluctuations.

48th Annual Meeting of the Division of Plasma Physics, October 30 – November 3, 2006, Philadelphia, Pennsylvania Energetic-Electron-Driven Alfvénic Modes.

Catalin Teodorescu, William Young, Richard Ellis, Adil Hassam

Applications: Motors Loudspeakers Galvanometers

Reduction of Neoclassical Transport and Observation of a Fast Electron Driven Instability with Quasisymmetry in HSX J.M. Canik1, D.L. Brower2, C. Deng2,

Magnetic fluctuation measurements in HSX and its impact on transport

Characteristics of Biased Electrode Discharges in HSX

Characteristics of Edge Turbulence in HSX

Studies of Bias Induced Plasma Flows in HSX

Two-Plate Waveguide

NATIONAL RESEARCH CENTER “KURCHATOV INSTITUTE”

Physics 122B Electricity and Magnetism

Lab: AC Circuits Integrated Science II.

Presentation transcript:

Flows and Instabilities Associated with an Extremely Narrow Current Sheet Presented by Stephen Vincena April 20, 2004 University of Maryland Second Workshop on Thin Current Sheets Collaborators: Walter Gekelman and Patrick Pribyl University of California, Los Angeles Large Plasma Device Laboratory DOE/NSF Basic Plasma Science Facility

Cathode discharge plasma Highly Ionized plasmas n ≈ 3 x /cm 3 Reproducible, 1Hz operation > 4-month cathode lifetime Up to 3.5kG DC Magnetic Field on axis Plasma column up to 2000R ci across diameter Over 450 Access ports, with 50 ball joints Computer Controlled Data Acquisition Microwave Interferometers Laser-Induced Fluorescence Large variety of probes Now a national user facility Overview of the experimental device

Electron current sheet generation with ‘Slot’ Cu plate: Length: 18cm=0.6  i, 45  e or  i Width: 1.9cm, 5  e or  i Thickness: 0.15, 0.4  e or  i, 13  e Glass-covered Copper rod 3/8” stainless Steel shaft epoxy

Probes: 3-axis, differentially wound magnetic induction probes for fluctuating magnetic fields. Langmuir probes biased to collection ion saturation current yields (assuming Te fixed) density fluctuations when calibrated with a microwave interferometer. Multi-sided Langmuir probes (Mach probes) for ion flow. Example: 1.2mm 4-sided mach probe Tungsten faces

Fixed magnetic probe Current sheet antenna  x =2mm Movable flow probe Fixed flow probe Transistor switch capacitors Current = 70A Voltage = 75 V He, B=500G…1.5 kG Photograph T shutter = 1  s View down axis of machine Geometry and Philosophy of data collection

Electron current drawn by slot Amperes/10 t/ (L/vA), L=20m

y (cm) x (cm) Mach number Movie of Parallel Ion Flow in a Perpendicular Plane R ci = 4.1 mm  = 3.8 mm y x z, B This movie is available at sf/vincena/umd04/movie1.avi sf/vincena/umd04/movie1.avi

Time of peak flow y (cm) x (cm) Mach number T=690  sec Parallel Ion Flow in a Perpendicular Plane R ci = 4.1 mm  = 3.8 mm

Parallel Ion Flow in a Perpendicular Plane y (cm) x (cm) Mach number T=1000  sec Time during spontaneous fluctuations

Peak parallel ion flow at times of maximum density gradient Fluctuations (Drift-Alfven waves) and peak current associated with relatively filled-in density profiles->cross-field transport x/  i Density (/cc)

Parallel Ion Flow in a Perpendicular Plane y (cm) x (cm) Mach number T=1000  sec Time during spontaneous fluctuations Correlation Measurements are Made in this Region

Density Fluctuations Due to Drift Waves Frequency: 0.2Fci y (cm) x (cm) This movie is available at ena/umd04/movie2.avi ena/umd04/movie2.avi

x/  i Density Parallel ion flow (V z /C s ) Perpendicular ion flow (V y /C s ) M-par M-perp #/cc

Time Series (Bx) FFT frequency (Hz) arb units x=0, y=0 (center) He, B = 500 G 3 axis magnetic probe inside current sheet Spontaneous fluctuations

Coherency Spectrum x (cm) m : movable probe f = fixed probe  z =2.24 m

First glimpse of electron solitary structures ? 1 Ghz amplifier Probe tip 12  X 27  To 4 GHz digitizer

Summary & Future work Observed strong parallel ion flows associated with a thin electron current sheet This flow is periodically disrupted by the formation of steep density gradients and the onset of drift wave turbulence. Building 3D mm-scale mach probe. Independently measure perpendicular ion flow using laser-induced fluorescence. Developing micro-scale electric field probes to study fine-scale (Debeye-length) electron structures (electron phase space holes) within the current sheet. Quantitative, scaled comparisons with drift wave theory and numerical predictions.