ИСТИНА

Recent observations of plasma and magnetic field, conducted by THEMIS missions in the magnetosheath, provided a lot of new experimental data about plasma jets, fast and dense plasma streams in the magnetosheath. A number of mechanisms have been proposed for the jet generation and are used for interpretation of various observations. Statistically, it has been shown that the duration of jets peaks at ~30 second and they are predominantly observed during intervals of quasi-radial IMF. It is believed that most of jets are formed at rippled quasi-parallel bow shock. However, this mechanism is difficult to apply for generation of large-scale jets of minute duration. We studied large-scale plasma jets, whose duration varies from 30 sec to 3 minutes. From THEMIS observations, it was collected 642 large-scale jets in the years 2007 – 2009. These data were used for verification of the existing generation mechanisms.