Dynamic properties of small-scale solar wind plasma fluctuations

Area of Science:

• Space Physics
• Plasma Physics
• Astrophysics

Background:

• Turbulent flows in the solar wind are complex phenomena.
• Understanding small-scale fluctuations is crucial for space weather prediction.
• Previous studies have provided insights but high-resolution data is key.

Purpose of the Study:

• To analyze small-scale fluctuations in solar wind ion flux.
• To investigate the statistical properties and characteristics of these fluctuations.
• To compare observations with theoretical models like Tsallis statistics and log-Poisson models.

Main Methods:

• Utilizing high temporal resolution (0.03s) measurements from the Bright Monitor of SW (BMSW) plasma spectrometer on the SPECTR-R spacecraft.
• Systematic analysis of solar wind ion flux fluctuation spectra across various scales (0.03s to 100s).
• Applying Tsallis statistics and log-Poisson models to analyze probability distribution functions and structure function scaling.

Main Results:

• Demonstrated a high level of intermittency in solar wind ion flux fluctuations.
• Observed extended self-similarity in the turbulent solar wind flow.
• Identified non-Gaussian probability distributions, indicating non-extensive behavior.
• Log-Poisson parametrization confirmed the presence of filament-like plasma structures.

Conclusions:

• Solar wind turbulence exhibits significant intermittency and non-Gaussian characteristics.
• Extended self-similarity and Tsallis statistics are applicable to solar wind fluctuations.
• Filament-like plasma structures are a common feature in turbulent solar wind flows.