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Title: MEASURING COLLISIONLESS DAMPING IN HELIOSPHERIC PLASMAS USING FIELD–PARTICLE CORRELATIONS

Abstract

An innovative field–particle correlation technique is proposed that uses single-point measurements of the electromagnetic fields and particle velocity distribution functions to investigate the net transfer of energy from fields to particles associated with the collisionless damping of turbulent fluctuations in weakly collisional plasmas, such as the solar wind. In addition to providing a direct estimate of the local rate of energy transfer between fields and particles, it provides vital new information about the distribution of that energy transfer in velocity space. This velocity-space signature can potentially be used to identify the dominant collisionless mechanism responsible for the damping of turbulent fluctuations in the solar wind. The application of this novel field–particle correlation technique is illustrated using the simplified case of the Landau damping of Langmuir waves in an electrostatic 1D-1V Vlasov–Poisson plasma, showing that the procedure both estimates the local rate of energy transfer from the electrostatic field to the electrons and indicates the resonant nature of this interaction. Modifications of the technique to enable single-point spacecraft measurements of fields and particles to diagnose the collisionless damping of turbulent fluctuations in the solar wind are discussed, yielding a method with the potential to transform our ability to maximize the scientificmore » return from current and upcoming spacecraft missions, such as the Magnetospheric Multiscale ( MMS ) and Solar Probe Plus missions.« less

Authors:
 [1];  [2]
  1. Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, MI 48109 (United States)
  2. Department of Physics and Astronomy, University of Iowa, Iowa City, IA 52242 (United States)
Publication Date:
OSTI Identifier:
22654261
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 826; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; COLLISIONAL PLASMA; CORRELATIONS; DISTRIBUTION; DISTRIBUTION FUNCTIONS; ELECTROMAGNETIC FIELDS; ELECTROSTATICS; ENERGY TRANSFER; FLUCTUATIONS; INTERACTIONS; LANDAU DAMPING; LANGMUIR FREQUENCY; MODIFICATIONS; PARTICLES; SOLAR WIND; SPACE; SPACE VEHICLES; TURBULENCE

Citation Formats

Klein, K. G., and Howes, G. G.. MEASURING COLLISIONLESS DAMPING IN HELIOSPHERIC PLASMAS USING FIELD–PARTICLE CORRELATIONS. United States: N. p., 2016. Web. doi:10.3847/2041-8205/826/2/L30.
Klein, K. G., & Howes, G. G.. MEASURING COLLISIONLESS DAMPING IN HELIOSPHERIC PLASMAS USING FIELD–PARTICLE CORRELATIONS. United States. doi:10.3847/2041-8205/826/2/L30.
Klein, K. G., and Howes, G. G.. Mon . "MEASURING COLLISIONLESS DAMPING IN HELIOSPHERIC PLASMAS USING FIELD–PARTICLE CORRELATIONS". United States. doi:10.3847/2041-8205/826/2/L30.
@article{osti_22654261,
title = {MEASURING COLLISIONLESS DAMPING IN HELIOSPHERIC PLASMAS USING FIELD–PARTICLE CORRELATIONS},
author = {Klein, K. G. and Howes, G. G.},
abstractNote = {An innovative field–particle correlation technique is proposed that uses single-point measurements of the electromagnetic fields and particle velocity distribution functions to investigate the net transfer of energy from fields to particles associated with the collisionless damping of turbulent fluctuations in weakly collisional plasmas, such as the solar wind. In addition to providing a direct estimate of the local rate of energy transfer between fields and particles, it provides vital new information about the distribution of that energy transfer in velocity space. This velocity-space signature can potentially be used to identify the dominant collisionless mechanism responsible for the damping of turbulent fluctuations in the solar wind. The application of this novel field–particle correlation technique is illustrated using the simplified case of the Landau damping of Langmuir waves in an electrostatic 1D-1V Vlasov–Poisson plasma, showing that the procedure both estimates the local rate of energy transfer from the electrostatic field to the electrons and indicates the resonant nature of this interaction. Modifications of the technique to enable single-point spacecraft measurements of fields and particles to diagnose the collisionless damping of turbulent fluctuations in the solar wind are discussed, yielding a method with the potential to transform our ability to maximize the scientific return from current and upcoming spacecraft missions, such as the Magnetospheric Multiscale ( MMS ) and Solar Probe Plus missions.},
doi = {10.3847/2041-8205/826/2/L30},
journal = {Astrophysical Journal Letters},
number = 2,
volume = 826,
place = {United States},
year = {Mon Aug 01 00:00:00 EDT 2016},
month = {Mon Aug 01 00:00:00 EDT 2016}
}
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