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0.8
20
a
0
b
0.6
1
−20
4
0.4
3
2
−40
2
1
−60
3
0.2
4
−80
0.0
−100
1E-005
1E-004
1E-003
1E-002
1E-005
1E-004
1E-003
1E-002
k 1/km
k 1/km
Fig. 7.7.
The ground vertical magnetic field. The curves 1
,
2
,
3
,
4 correspond to
T
=30
,
100
,
300
,
1000 s
,k
y
=0
Non-Meridional Propagation
Inclined Geomagnetic Field
The change in amplitude and phase of
R
AA
depending on
k
y
for series of fixed
values
k
x
is depicted in Fig. 7.8. Curves 1
,
2
,
3
,
4 refer to
k
x
=10
−
5
,
10
−
4
,
10
−
3
,
10
−
2
km
−
1
, respectively. The calculations were carried out for
Σ
P
=0
.
116
×
10
9
km/s,
Σ
H
=0
.
139
10
9
km/s,
c
A
=10
3
km/s,
h
= 100 km, and
I
=
π/
4.
The ground is a half-space with
σ
g
=9
×
10
8
s
−
1
. Note a deep minimum in
the value of
R
AA
and a sharp change in phase at
k
y
=10
−
4
km
−
1
. Since
perturbations of horizontal scale greater than 10
4
km are not interesting to
ionospheric physics, then
R
AA
may be considered as a constant.
Figure 7.9 demonstrates the dependence of the reflection coecient
R
AA
of
the Alfven wave and the coecient of its transformation
R
SA
into the FMS-
wave on the integral Pedersen conductivity of the ionosphere. The Alfven
velocity
c
A
= 1100 km/s and the high-conductive ground half-space with con-
ductivity
σ
g
=9
×
10
8
s
−
1
(0
.
1 Ohm
−
1
). The inclination
I
=20
◦
(dashed lines)
and
I
=60
◦
(solid lines).
T
= 100 s and meridional and azimuthal wavenum-
bers
k
x
=10
−
2
km
−
1
and
k
y
=10
−
3
km
−
1
, respectively.
×
1.0
3
0
3, 4
b
4
a
0.8
-40
2
1
0.6
-80
0.4
-120
2
1
0.2
-160
0.0
-200
1E-006
1E-005
1E-004
1E-003
1E-002
1E-001
1E-006
1E-005
1E-004
1E-003
1E-002
1E-001
k
y
1/km
k
y
1/km
Fig. 7.8.
Absolute value (a) and phase (b) of the reflection coecient
R
AA
as a
function of
k
y
for fixed values
k
x
=10
−
5
(1), 10
−
4
(2), 10
−
3
(3), and 10
−
2
km
−
1
(4). Dip angle
I
=
π/
4
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