抄録
The interplanetary scintillation observations with a large antenna system have been carried out at 2, 8 and 22GHz to investigate the solar wind near the sun. The solar wind velocities estimated by fitting the theoretical model for IPS spectra indicate that the solar wind is markedly driven at distances between 10 and 30 solar radii. The derived scintillation indices show a good agreement with a radial dependence of R-1.6 for >5 solar radii, and also display a slight enhancement around the region where the solar wind acceleration occurs. The latter fact implies that plasma fluctuations are enhanced in the acceleration region.
