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Updated: Jun 8, 2026
10:53
Simultaneous Measurement of Turbulence and Particle Kinematics Using Flow Imaging Techniques
Published on: March 12, 2019
Two-dimensional kinetic turbulence in the solar wind.
F Valentini1, F Califano, P Veltri
1Dipartimento di Fisica and CNISM, Universitá di Pisa, 56127 Pisa, Italy.
Physical Review Letters
|September 28, 2010
Summary
We show that solar wind turbulence can develop along the parallel direction towards short scales. This challenges previous findings and highlights the role of kinetic effects in plasma dynamics.
Area of Science:
- Plasma Physics
- Astrophysics
- Space Science
Background:
- Solar wind turbulence exhibits anisotropy, with energy spectra predominantly perpendicular to the magnetic field in large-scale simulations.
- Previous studies using magnetohydrodynamics and particle-in-cell models focused on fluid wavelengths.
Purpose of the Study:
- To investigate the evolution of energy spectra in solar wind turbulence across two decades of wavelengths around the ion inertial scale.
- To explore turbulence development at shorter scales where kinetic effects dominate.
Main Methods:
- Utilizing the first 2D hybrid-Vlasov simulations for solar wind turbulence.
- Analyzing energy spectra evolution across a range of wavelengths.
Main Results:
- Evidence suggests the parallel direction is a privileged pathway for turbulence development towards shorter scales.
- This contrasts with previous findings emphasizing perpendicular anisotropy.
Conclusions:
- Kinetic effects play a crucial role in governing plasma dynamics at short scales.
- The parallel direction is significant for turbulence evolution in the solar wind.
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