MHD-Waves in Layered Media - Hydromagnetic Waves in the Magnetosphere and the Ionosphere - page 230

inverse X ε 1 / m . Then R AA = 1 , the total wave magnetic field above

the ionosphere is nil, as it takes place at the boundary of the perfect dielectric.
When passing from day to night, the R AA changes from positive to negative
values, so there is a transition region where R AA →

−

0 . The Q-factor of the
magnetospheric resonator at this local time steeply goes down.
There is another important point that follows from the calculations. The
Alfven wave incident onto the ionosphere is transformed not only into the same
mode but into the FMS as well that follows from the above reasoning. There
are two peculiar properties of this mode. The first one is that the mode damps
exponentially as moving away from the ionosphere to the magnetosphere with
the scales of order of the transversal scale of the initial wave. Other words, it is
possible to reveal this wave only on low altitude satellites. An intensity of this
reflected mode is controlled not so much by the magnetospheric properties as
by the conductivity of the ground.

References

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