Energetics of the magnetospheric superstorm on November 20, 2003 |
| |
| Authors: | Karavaev Yu A Sapronova L A Bazarzhapov A D Saifudinova T I Kuz’minykh Yu V |
| |
| Institution: | 1.Institute of Solar and Terrestrial Physics, Siberian Branch, Russian Academy of Sciences, Irkutsk, Russia
; |
| |
| Abstract: | The magnetospheric storm on November 20, 2003 was one of two greatest events in 1957–2003. The D
st* index reached −472 nT, the polar cap potential drop exceeded 200 kV, the polar cap boundary expanded up to Φ = 60°, the plasma
layer density in the synchronous orbit reached 5 cm−3, and the inner edge of the plasma sheet penetrated up to L ∼ 1.5R
E. The sequence of disturbance modes including some previously unknown is described. The distribution of the total power input
into the magnetosphere between the ionosphere (power Q
i) and the ring current (Q
DR), as well as the relative roles of the spontaneous substorms and the driven disturbances in the creation of the DR current, is analyzed. The values of the parameter α = Q
DR/Q
i are calculated with a step of 5 min. It is shown that intervals with α ≪ 1 and with maximums α ≫ 1 were observed in the events
under consideration. These results contradict the dominant opinion that the energy input into the magnetosphere during disturbances
is primarily dissipated in the ionosphere. The two types of α maximums are observed: one in the mode of a prevailing spontaneous
substorm and the other in the mixed mode of the substorm and driven disturbance. It is concluded that both types of the maximums
and corresponding enhancements of the DR current appeared due to the plasma turbulization processes in the substorm current
wedge. The parameter α appears to slowly increase from α ≪ 1 to α > 1 with increasing activity level; this trend supports
the driven model of creating the DR current due to an increase in the electric field of the solar wind. |
| |
| Keywords: | |
| 本文献已被 SpringerLink 等数据库收录！ |
|
