Tearing mode in thin current sheets of the Earth’s magnetosphere: A scenario of transition to unstable state |
| |
| Authors: | L M Zelenyi A P Kropotkin V I Domrin A V Artemyev H V Malova V Y Popov |
| |
| Institution: | 1.Space Research Institute,Russian Academy of Sciences,Moscow,Russia;2.Skobeltsyn Institute of Nuclear Physics,Moscow State University,Moscow,Russia;3.Physics Department,Moscow State University,Moscow,Russia |
| |
| Abstract: | The results of numerical modeling of thinning process in the Earth’s magnetotail current sheet are compared with the model
of an anisotropic current sheet in collisionless space plasma. Stability of the current sheet during its evolution is investigated.
In the evolution one can distinguish three basic stages: 1) transformation of the initial two-dimensional “isotropic” equilibrium
that is well described within the MHD-approximation into a relatively thin current structure; 2) further kinetic evolution,
as a result of which the virtually one-dimensional, extremely thin current sheet is formed; 3) relaxation of the system into
a new equilibrium that can be stable or unstable. A substorm scenario of transformation of the magnetospheric tail and its
transition into the unstable state is suggested. The spontaneously appearing tearing disturbance favors a current sheet disruption.
It is shown that the estimate of a tearing mode wavelength, obtained from the model, is in accordance with experimental observations
during the explosive phase of substorms. |
| |
| Keywords: | |
| 本文献已被 SpringerLink 等数据库收录！ |
|
