Impact of solar wind parameters on geomagnetic activity during the main phase of strong magnetic storms

The relationship between the mean values of auroral activity indices and SW parameters during the periods of strong magnetic storms (|Dstmin| = 100 +/- 10 nT) induced by SW different types is studied. 24 magnetic storms induced by (6) Sheath, (9) CIR, and (9) ICME events are selected for the period 1990-2020. It is shown that the against the background of the dependence of the auroral activity indices (AE, Kp and SME) on the SW electric field, the value of AE, Kp and SME indices is impacted by the IMF sigma & Vcy;. The geomagnetic indices increase with growth of the IMF sigma B magnitude. It is found that Sheath events have high geomagnetic index values in contrast to CIR and ICME. The SW type determines the relationship between geomagnetic indices and IMF sigma & Vcy;. The coefficient of correlation between IMF sigma B and Pd for Sheath (r = 0.65) has a close value with the correlation coefficients for the CIR and ICME events.