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10
0
10
1
Day
T = 100 s
|E
x
|
|b
y
|
10
0
10
−1
|E
y
|
|b
x
| ≈ |b
z
|
10
−1
10
−2
200
0
200
200
0
200
Distance, km
Distance, km
Fig. 11.11.
The spatial distribution of the above-ionosphere magnetic (left panel)
nearby a resonance region for an incident likewise FLR-wave beam.
b
y
is a sum
of the incident and reflected Alfven wave magnetic components.
b
x
≈ b
z
is the
magnetic field transformed into the FMS-wave. The right panel shows the same
dependencies for the electric components.
E
x
corresponds to the total horizontal
electric field in the Alfven polarization, and
E
y
is the total electric field in the FMS-
polarization. The curves are computed for two geoelectric cross-sections (see Table
11.2). The curves on the left panel represent both models. Solid lines on the right
panel refer to the 1-st model and the dashed to the 2-nd. The resonance period is
100 s. The geomagnetic dip is
I
=60
◦
. Dayside ionosphere:
Σ
P
=1
.
2
×
10
8
km/s,
Σ
P
=1
.
4
×
10
8
km/s
|
b
x
|≈|
b
z
|
and reflected Alfven wave magnetic components.
is the mag-
netic field of the FMS-wave caused by the initial Alfven wave. Their dis-
tributions coincide virtually at any distances from the base of the reso-
nance shell
x
= 0. The right panel shows the same dependencies for the
electric wave components.
E
x
corresponds to the total horizontal electric
field in the Alfven polarization, and
E
y
is the total electric field in the
FMS-polarization.
Note that the magnetic field is almost insensitive to the geoelectric prop-
erties. So the curves on the left panel represent both models. Solid lines on
the right panel refer to the 1-st model and the dashed to the 2-nd. It can be
seen that
E
x
has the same half-width as the initial wave. The influence of the
geoelectric properties on the intensity of the electric component
E
x
is clearly
visible.
Such dependencies enable us to construct the above ionospheric spatial
curves of apparent resistivity
ρ
ap
(
x
). Similar to the relations (11.22) and
(11.26) on the ground, one can define an apparent resistivity
ρ
ap
(
x
)above
the ionosphere determined as
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