Parameters of the turbulence of the interplanetary plasma derived from scintillation observations of the quasar 3C 48 at the solar-activity minimum

Temporal spectra of interplanetary scintillations of the strong radio source 3C 48 based on 111 MHz observations on the Large Scanning Antenna of the Lebedev Physical Institute obtained near the solar-activity minimum are analyzed. Measurements of the temporal spectrum of the scintillations are used to estimate the angular size of the source, the velocity of inhomogeneities, and the power-law index for the spatial spectrum of the turbulence in the interplanetary plasma. The mean angular size of the source is θ ₀ = 0.326″ ± 0.016″, and the mean index for the three-dimensional turbulence spectrum is n = 3.7 ± 0.2. There is some evidence that n decreases in the transition from the fast, high-speed to the slow, low-latitude solar wind.