||The ROCSAT-1 satellite was launched into a circular orbit at about 600km altitude with an inclination of 35 degrees, with which the globale responses of four magnetic storm events occurred on 2000/07/15, 2001/03/31, 2003/1029, 2003/11/20, respectively, were analyzed in the mid- and low-latitude ionosphere. The data of 50 days before storm onset were taken to construct the background conditions. According to the satellite pathes of the storm events, a division for dayside and nightside can be roughly defined. The daytime penetration electric fields, eastward resulted from southward turning and westward from northward turning of the IMF Bz, enable the mid- and low- latitude ionosphere to change.|
The variation of ion drifts and charge particle densities with the local time and the magnetic latitudes observed by the IPEA on board ROCSAT-1 may be used to build up the distribution of the E×B drifts and plasma densities for the quiet time and storm time conditions. In the observations, we find that the increases of the daytime ionospheric plasma densities may result from the eastward penetration electric field in the storm time; the densities decrease in the nighttime. Moreover, neutral wind blowing from the high latitudes may also cause the charged particle density of ionosphere in mid- and low-latitude to rise.
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