ИСТИНА

We have studied the global magnetospheric structure and its dynamics during 2009-2012 using satellite measurements. We determine the mean position of the outer radiation belt (ORB) boundaries at the Earth surface using regular measurements of E > 200 keV electron uxes onboard Coronas-Photon since March till November 2009 and E > 100 keV electron uxes onboard Meteor-M #1 since November 2009 till May 2012. These low altitude polar satellites crossed the external boundaries of ORB approximately every 1.5 hrs. It was obtained that the high-latitude ORB boundary is controlled by both geomagnetic (internal) and magnetospheric magnetic elds. The extremely quiet conditions allowed us to separate the eects induced by internal and external factors. It has been found that at the ionospheric level the high-latitude boundary of ORB rotates with the Earth but slightly shifts to the night side due to large-scale magnetospheric currents. Variation of ORB boundaries have been determined to depend on UT (universal time). By adding disturbed periods we can catch the dependence between dst-index and the boundary sizes. It was found that the boundary enlarges while dst decreases