ИСТИНА

It is believed that magnetosheath plasma jets allow plasma penetration inside the magneto- sphere. Plasma jets are dened as localized structures of dense and fast plasma whose energy density is higher than that of the upstream solar wind. The distinctive feature of large-scale jets is characteristic duration of several minutes that corresponds to space scales extending up to more than 10 Re. The large-scale jets might be induced by interplanetary discontinuities in interaction with the bow shock or foreshock region.THEMIS multipoint observation of plasma and magnetic field were used to collect about 1000 large-scale plasma jets in the dayside mag- netosheath. The jets can either flow along the streamlines around the magnetosphere or move across the streamlines and interact with the magnetopause. The interaction produces specific geomagnetic variations, which can be observed by GOES satellites or by round-based magnetometers. We found that more than 70% of large-scale jets did interact with the magnetopause. The interaction might result in penetration of the magnetosheath plasma across the magnetopause. This process can be described by a mechanism of impulsive penetration. Based on predictions of this mechanism for the collected statistics, we estimated the average transport of the magnetosheath plasma across the dayside magnetopause into the magnetosphere.