3:45 PM - 4:00 PM
[PEM07-08] Ballooning instability with the magnetosphere-ionosphere feedback coupling
Keywords:aurora, magnetosphere-ionosphere coupling, instability
In the present study, we have investigated the ballooning and the feedback instabilities in the same theoretical framework. Our linear analysis demonstrates that, as the interchange term increases, the "unstable" shear Alfven waves with the opposite sign of the real eigenvalues in their lowest harmonic branch collide with each other and transit to the ballooning mode. It implies that competitions and/or interactions between the two instabilities may provide a plausible explanation of auroral breakup triggered through the M-I coupling.
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