Interpreting Power Anisotropy Measurements in Plasma Turbulence

Abstract

A relationship is derived between power anisotropy and wavevector anisotropy in turbulent fluctuations. This can be used to interpret plasma turbulence measurements, for example in the solar wind. If fluctuations are anisotropic in shape then the ion gyroscale break point in spectra in the directions parallel and perpendicular to the magnetic field would not occur at the same frequency, and similarly for the electron gyroscale break point. This is an important consideration when interpreting solar wind observations in terms of anisotropic turbulence theories. Model magnetic field power spectra are presented assuming a cascade of critically balanced Alfven waves in the inertial range and kinetic Alfven waves in the dissipation range. The variation of power anisotropy with scale is compared to existing solar wind measurements and the similarities and differences are discussed.

5 pages, 3 figures, published version

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Cited by in corpus (26)

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• Recent progress in astrophysical plasma turbulence from solar wind observations
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• The Nature of Subproton Scale Turbulence in the Solar Wind
• Power and spectral index anisotropy of the entire inertial range of turbulence in the fast solar wind
• Nature of Kinetic Scale Turbulence in the Earth's Magnetosheath
• Anisotropy of Alfvénic Turbulence in the Solar Wind and Numerical Simulations
• Three-Dimensional Structure of Solar Wind Turbulence
• Ion Scale Electromagnetic Waves in the Inner Heliosphere
• Collisionless Reconnection in Magnetohydrodynamic and Kinetic Turbulence
• The Role of Proton-Cyclotron Resonance as a Dissipation Mechanism in Solar Wind Turbulence: A Statistical Study at Ion-Kinetic Scales
• Evidence of Critical Balance in Kinetic Alfven Wave Turbulence Simulations
• Physical Interpretation of the Angle Dependent Magnetic Helicity Spectrum in the Solar Wind: The Nature of Turbulent Fluctuations near the Proton Gyroradius Scale
• Anisotropy of Solar-Wind Turbulence in the Inner Heliosphere at Kinetic Scales: PSP Observations
• Magnetic Reconnection May Control the Ion-Scale Spectral Break of Solar Wind Turbulence
• Laguerre-Hermite Pseudo-Spectral Velocity Formulation of Gyrokinetics
• Frame Dependence of the Electric Field Spectrum of Solar Wind Turbulence
• Three-dimensional magnetic reconnection in particle-in-cell simulations of anisotropic plasma turbulence
• Spectral breaks of Alfvenic turbulence in a collisionless plasma
• Anisotropies in the HI gas distribution toward 3C196
• Magnetic Field Rotations in the Solar Wind at Kinetic Scales
• Weak Alfvénic turbulence in relativistic plasmas. Part 1. Dynamical equations and basic dynamics of interacting resonant triads
• Optimisation of confinement in a fusion reactor using a nonlinear turbulence model
• Spectrum of kinetic plasma turbulence at 0.3-0.9 astronomical units from the Sun
• The uncertainty of local background magnetic field orientation in anisotropic plasma turbulence
• Magnetic Energy Transfer and Distribution between Protons and Electrons for Alfvénic Waves at Kinetic Scales in Wavenumber Space