SPECTRUM OF THE INTERPLANETARY PLASMA TURBULENCE AT A DISTANCE FROM THE SUN GREATER THAN 1 AU

Abstract

Purpose: Making analysis of variations of fast and slow solarwind parameters at distances from the Sun of about 1 AU and more. Design/methodology/approach: The method of Feynman pathintegrals is applied to calculate the temporal spectra and dispersion dependences of the drift velocity of interplanetary scintillations. The calculated spectra and dispersion dependences have been compared with the experimental ones to determine the solar wind parameters. Findings:The parameters of fast and slow solar wind are determined and obtained data analyzed by the results of observations with the UTR-2 and URAN-2 radio telescopes made in 2003–2011. Based on these results, the empirical radial dependences of the turbulence spectra for fast and slow solar wind have been built. Conclusions: The slow solar wind turbulence is shown on the average corresponding to the Kolmogorov law of hydrodynamic turbulence. The turbulence of fast quasi-stationary solar wind is well described by the Iroshnikov–Kraichnan magnetohydrodynamic turbulence.

Keywords

• interplanetary scintillation
• fast and slow solar wind
• three-dimensional spatial spectrum of electron density fluctuations