AN ANALYSIS OF THE SOLAR CO-ROTATING PERIODIC STRUCTURE WITH GEOMAGNETIC DISTURBANCES DATA

Data of solar wind speed and geomagnetic disturbances in the 20th solar cycle are statistically compared. There seems to be a similarity of the corotating periodic structure deduced from both sets of data. An autocorrelation analysis of geomagnetic index C₉ of 1900-1979 shows that in a fairly long period there exist 13-day and 27-day periodic components. It can be concluded that on the corona, there might be some inherent distribution structures. The reflection of such structures by C₉ index is affected by the level of solar activety and North-South asymmetry of sunspot area.