Структура и динамика полярных токовых систем : материалы международного симпозиума «Полярные геомагнитные явления», 25-31 мая, Суздаль, СССР / Акад. наук СССР, Кол. фил. им. С. М. Кирова, Поляр. геофиз. ин-т. – Апатиты : [б. и.], 1988.

STATISTICAL RELATIONSHIPS BETWEEN THE HIGH-LATITUDE MAGNETIC ACTIVITY AND THE SOLAR WIND PARAMETERS V gw AND B g . Until now the most representative characteristics of the auroral zone magnetic activity are AU and AL-indices showing the intensity of the eastward and westward electrojets and also their sum AE=AU+AL.. To indicate the polar cap magnetic activity Troshichev et al.(1979) have proposed to use the value of nearpole geomagnetic disturbances due to trans polar midnight-noon electric currents. The appropriate index named MAGPC is in a good relation to all solar wind parameters including the IMP southern component B 0 and velocity V ^ (Troshichev and Andrezen,1985). The correlation is maximum with the coupling electric field Em Em = vBT 8in2e/2 provided the relationship between MAGPC and Em is presented by the linear law. Pig. 1 shows, however, that MAGPC index approaches some asymptote value when electric field becomes sufficiently large. The similar tendency to saturation is also observed in potential drop across the polar cap (Reiff et al.,1981; Wygant et al.,1983; Doyle and Burke,1983). The IMP southern component control of the auroral zone magnetic activity is well established long ago (Arnoldy,1971s Foster et al.,1971i Kokubun, 1972; Meng et al.,1973, etc.). The influence of the solar wind velocity on the AU MAGPC, nT irBj-Sin 28 / 2 ,пТ-кт/s Fig. 1. MAGPC indices vs. electric field E ^ B ^ a v t B y + B 2 )1/2 (top) and merging electric field Em =vBTsin2e/2 (bottom) (Troshichev and Andrezen,1985). II6