Open AccessSimulation of feedback instability in the coupled magnetosphere‐ionosphere system
Author(s) -
Hasegawa Hiroki,
Ohno Nobuaki,
Sato Tetsuya
Publication year - 2010
Publication title -
journal of geophysical research: space physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2009ja015093
Subject(s) - ionosphere , physics , instability , magnetosphere , geophysics , plasma , electric field , field line , equator , dipole , computational physics , substorm , coupling (piping) , mechanics , latitude , quantum mechanics , mechanical engineering , astronomy , engineering
Quiet auroral arcs formation has been investigated theoretically and numerically in a self‐consistent dynamic way. By using a three‐dimensional magneto‐hydro‐dynamics simulation of a dipole magnetosphere‐ionosphere coupling system, it is shown that multiple longitudinally striated structures of the ionospheric plasma density and the field‐aligned current are formed, resulting from nonlinear feedback instability. The areas where these structures appear are consistent with the prediction by the integrated feedback theory that includes the effects of the spatially non‐uniform electric field and non‐uniform plasma density. Effects of the difference of the field line lengths between the ionosphere and the magnetospheric equator over the auroral latitudes are also discussed on the feedback instability.