Some Statistical Aspects of Solar-Activity Indices

Abstract

This study aims to obtain characteristics of some indices of solar activity and relations among them. First the following relation between sunspot number S and international magnetic character-figure C was obtained : C=α+S/(βS+γ) This equation holds good in both cases of annual and monthly means.
Next the sunspot number was analyzed from the standpoint of view that the tide-generating forces of the planets affect the sunspot activity. In both cases of the earth and Jupiter, the revolution-period and its half period were detected in the variation of spot number. These variations differ at the increasing stage of sunspot from at the decreasing stage.
Instead of individual analysis concerning with Mercury or Vienus, the combined effects of 4 planets were examined. As the result, 88.9-, 142.3-, 178-year period and other periods were brought to light.