Statistical nature of geomagnetic storms

摘要: On the basis of geomagnetic activity indices and solar wind parameters, a superposed epoch analysis has been conducted for more than 300 storms. The intensity magnetic storms is found to depend on duration main phase; larger have longer timescales. For intense storms, however, not only energy injection into ring current but also strength important in determining their size. It confirmed that southward component interplanetary field plays crucial role both triggering storm phase magnitude time profile rate during tends two peaks. This particularly case where second peak first. Implications our findings are discussed terms existing concept recent observations particles disturbances.