The Recurrent Solar Wind Streams Observed by Interplanetary Scintillation of 3C 48

Abstract

Abstract The interplanetary scintillation of 3C 48 was observed by two spaced receivers (69.3 MHz) during February and March 1971. The recurrent property of the observed velocity increases of the solar wind is clearly seen, and their recurrent period is 24 to 25 days. This value is shorter than the synodic period of 27 days, but this deviation may be explained by the displacement of the closest point to the sun on the line of sight for 3C 48. A comparison with the data of the wind velocity obtained by space probes shows that the observed enhancements are associated with two high velocity streams corotating around the sun. The enhancements of the scintillation index precede by about two days the velocity enhancements, and it may be concluded that such enhancement of the scintillation index has resulted from the compressed region of the interplanetary plasma formed in front of the high velocity corotating stream.