抄録
There are many Pi pulsations in magnetosphere. We think that the magnetospheric cavity resonance process is affected by the change in the Alfven speed distribution. We carry out the numerical calculation to make sure our ideas in one dimensional model. We calculate the frequency characteristics of the MHD Responses of the magnetosphere to the magnetopause perturbations in the magnetosphere. And we concluded that the eigen-frequency and amplitudes of the cavity modes are influenced by the averaged Alfven speed.
