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Title: Suppression of phase mixing in drift-kinetic plasma turbulence

Abstract

Transfer of free energy from large to small velocity-space scales by phase mixing leads to Landau damping in a linear plasma. In a turbulent drift-kinetic plasma, this transfer is statistically nearly canceled by an inverse transfer from small to large velocity-space scales due to “anti-phase-mixing” modes excited by a stochastic form of plasma echo. Fluid moments (density, velocity, and temperature) are thus approximately energetically isolated from the higher moments of the distribution function, so phase mixing is ineffective as a dissipation mechanism when the plasma collisionality is small.

Authors:
 [1];  [2];  [2];  [3];  [2];  [4];  [2];  [5]
  1. Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Campus, Didcot OX11 0QX (United Kingdom)
  2. (United Kingdom)
  3. Brasenose College, Radcliffe Square, Oxford OX1 4AJ (United Kingdom)
  4. Rudolf Peierls Centre for Theoretical Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP (United Kingdom)
  5. OCIAM, Mathematical Institute, University of Oxford, Andrew Wiles Building, Radcliffe Observatory Quarter, Woodstock Road, Oxford OX2 6GG (United Kingdom)
Publication Date:
OSTI Identifier:
22600012
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 23; Journal Issue: 7; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; DISTRIBUTION; DISTRIBUTION FUNCTIONS; FREE ENERGY; INHIBITION; LANDAU DAMPING; MIXING; PLASMA; PLASMA DENSITY; SPACE; STOCHASTIC PROCESSES; TURBULENCE; VELOCITY

Citation Formats

Parker, J. T., E-mail: joseph.parker@stfc.ac.uk, OCIAM, Mathematical Institute, University of Oxford, Andrew Wiles Building, Radcliffe Observatory Quarter, Woodstock Road, Oxford OX2 6GG, Brasenose College, Radcliffe Square, Oxford OX1 4AJ, Highcock, E. G., Rudolf Peierls Centre for Theoretical Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP, Schekochihin, A. A., Merton College, Merton Street, Oxford OX1 4JD, and Dellar, P. J. Suppression of phase mixing in drift-kinetic plasma turbulence. United States: N. p., 2016. Web. doi:10.1063/1.4958954.
Parker, J. T., E-mail: joseph.parker@stfc.ac.uk, OCIAM, Mathematical Institute, University of Oxford, Andrew Wiles Building, Radcliffe Observatory Quarter, Woodstock Road, Oxford OX2 6GG, Brasenose College, Radcliffe Square, Oxford OX1 4AJ, Highcock, E. G., Rudolf Peierls Centre for Theoretical Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP, Schekochihin, A. A., Merton College, Merton Street, Oxford OX1 4JD, & Dellar, P. J. Suppression of phase mixing in drift-kinetic plasma turbulence. United States. doi:10.1063/1.4958954.
Parker, J. T., E-mail: joseph.parker@stfc.ac.uk, OCIAM, Mathematical Institute, University of Oxford, Andrew Wiles Building, Radcliffe Observatory Quarter, Woodstock Road, Oxford OX2 6GG, Brasenose College, Radcliffe Square, Oxford OX1 4AJ, Highcock, E. G., Rudolf Peierls Centre for Theoretical Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP, Schekochihin, A. A., Merton College, Merton Street, Oxford OX1 4JD, and Dellar, P. J. 2016. "Suppression of phase mixing in drift-kinetic plasma turbulence". United States. doi:10.1063/1.4958954.
@article{osti_22600012,
title = {Suppression of phase mixing in drift-kinetic plasma turbulence},
author = {Parker, J. T., E-mail: joseph.parker@stfc.ac.uk and OCIAM, Mathematical Institute, University of Oxford, Andrew Wiles Building, Radcliffe Observatory Quarter, Woodstock Road, Oxford OX2 6GG and Brasenose College, Radcliffe Square, Oxford OX1 4AJ and Highcock, E. G. and Rudolf Peierls Centre for Theoretical Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP and Schekochihin, A. A. and Merton College, Merton Street, Oxford OX1 4JD and Dellar, P. J.},
abstractNote = {Transfer of free energy from large to small velocity-space scales by phase mixing leads to Landau damping in a linear plasma. In a turbulent drift-kinetic plasma, this transfer is statistically nearly canceled by an inverse transfer from small to large velocity-space scales due to “anti-phase-mixing” modes excited by a stochastic form of plasma echo. Fluid moments (density, velocity, and temperature) are thus approximately energetically isolated from the higher moments of the distribution function, so phase mixing is ineffective as a dissipation mechanism when the plasma collisionality is small.},
doi = {10.1063/1.4958954},
journal = {Physics of Plasmas},
number = 7,
volume = 23,
place = {United States},
year = 2016,
month = 7
}
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