Generalized dimensions for fluctuations in the solar wind

Area of Science:

• Space Physics
• Plasma Physics
• Nonlinear Dynamics

Background:

• Solar wind plasma exhibits complex behaviors in the inner heliosphere.
• Alfvénic turbulence is a key component of solar wind dynamics.

Purpose of the Study:

• To analyze solar wind plasma velocity time series.
• To investigate the multifractal structure of the solar wind attractor.
• To reduce noise in observational data for clearer analysis.

Main Methods:

• Utilized Helios 2 spacecraft data from the inner heliosphere.
• Applied singular-value decomposition filtering to reduce data noise.
• Calculated generalized dimensions to characterize the attractor's structure.

Main Results:

• Singular-value decomposition effectively filtered noise from solar wind velocity data.
• The solar wind attractor in the inner heliosphere displays a multifractal structure.
• The multifractal spectrum aligns with a weighted baker's map model.

Conclusions:

• The solar wind exhibits complex, multifractal dynamics in the inner heliosphere.
• Data filtering techniques are crucial for revealing underlying physical structures.
• The findings support models of self-similar processes in turbulent plasmas.