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the final expression for
Φ
4
A
:
i
A
0
k
0
2
Φ
4
A
≈−
[
C
+ln(
−
Z
0
)]
.
(8.25)
Substituting (8.24) and (8.25) into (8.12) and (8.13) for components of the
magnetic mode at the ground, we find
b
(
g
)
SA
b
(
g
)
zA
=
i
1
,
A
0
√
2
π
Y
sin
I
X
1
x
+
i
(
δ
i
+
h
)
−
A
0
√
2
π
Y
sin
I
X
E
(
g
)
SA
(
x
)=
E
(
g
)
(
x
)=
−
ik
0
[
C
+ln(
−
Z
0
)]
.
(8.26)
y
1 the vertical magnetic component
b
(
g
z
carries the same infor-
mation about above ionosphere wave structure as the horizontal component
b
(
g
x
. Ratio
b
(
g
z
/E
(
g
y
is completely determined by the structure of the field
inside the FLR-region:
For
|
kd
g
|
ik
0
b
(
g
)
1
[
x
+
i
(
δ
i
+
h
)] [
C
+ln(
b
x
b
z
z
E
(
g
)
=
Z
0
)]
,
=
i.
−
y
Numerical Examples
Let the ground be a half-space with conductivity
σ
g
,
and the ionospheric
model corresponds to the middle latitude dayside ionosphere in the maximum
of solar activity. The half-width
δ
i
and the resonance periods for
L
=2
,
3
,
4
are found from Fig. 6.6. Chosen parameters are shown in Table 8.1.
Let the total magnetic wave-field above the ionosphere be given by (8.15),
in which instead of
b
(
i
)
0
is substituted by the total amplitude of the incident
Table 8.1.
A ground-ionosphere model used in the numerical calculations.
σ
g
is a
specific conductivity of the ground half-space.
Σ
P
and
Σ
P
are the Pedersen and Hall
integral conductivities. The ionospheric model corresponds to the middle latitude
dayside ionosphere in the maximum of solar activity. The half-width
δ
i
of a resonance
shell corresponds to the resonance period for
L
=2
,
3
,
4.
h
is the height of the
conductive thin ionospheric layer
Parameter
Value
1
.
6
×
10
8
km/s
Σ
P
1
.
75
×
10
8
km/s
Σ
H
3
×
10
6
s
−
1
σ
g
h
130 km
δ
i
8km (
T
=20s,
L
=2)
δ
i
13
.
5km (
T
=80s,
L
=3)
δ
i
25 km, (
T
= 210 s,
L
=4)
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