Spectrum of kinetic plasma turbulence at 0.3-0.9 astronomical units from the Sun

Abstract

We investigate spectral properties of turbulence in the solar wind that is a weakly collisional astrophysical plasma, accessible to in-situ observations. Using the Helios search coil magnetometer measurements in the fast solar wind, in the inner heliosphere, we focus on properties of the turbulent magnetic fluctuations at scales smaller than the ion characteristic scales, the so-called kinetic plasma turbulence. At such small scales, we show that the magnetic power spectra between 0.3 and 0.9 AU from the Sun have a generic shape $\sim f^{-8/3}\exp (-f/f_d)$ where the dissipation frequency $f_d$ is correlated with the Doppler shifted frequency $f_{\rho e}$ of the electron Larmor radius. This behavior is statistically significant: all the observed kinetic spectra are well described by this model, with $f_d=f_{\rho e}/1.8$. Our results indicate that the electron gyroradius plays the role of the dissipation scale and marks the end of the electromagnetic cascade in the solar wind.

Published in PhysRevE in June 2021 https://ui.adsabs.harvard.edu/abs/2021PhRvE.103f3202A/abstract. arXiv admin note: substantial text overlap with arXiv:2004.01102

References in corpus (10)

• The Evolution and Role of Solar Wind Turbulence in the Inner Heliosphere
• Recent progress in astrophysical plasma turbulence from solar wind observations
• Solar wind turbulent spectrum at plasma kinetic scales
• Whistler mode waves and the electron heat flux in the solar wind: Cluster observations
• Critical Balance and the Physics of MHD Turbulence
• Anisotropy of third-order structure functions in MHD turbulence
• Whistler Waves and Electron Properties in the Inner Heliosphere: Helios Observations
• Variability Of The Magnetic Field Power Spectrum In The Solar Wind At Electron Scales
• Anisotropies of the magnetic field fluctuations at kinetic scales in the solar wind : Cluster observations
• A Model for Dissipation of Solar Wind Magnetic Turbulence by Kinetic Alfvén Waves at Electron Scales: Comparison with Observations

Cited by in corpus (1)

• Diffuse Josephson Radiation in Turbulence