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× 10
2
b
200
0.1
T
3
a
T
2
150
T
1
0.05
100
50
0
0
2
3
4
5
6
2
3
4
5
6
L
−
shell
L
−
shell
1.5
× 10
2
x 10
4
1
c
d
1
0.5
0.5
0
0
2
3
4
5
6
2
3
4
5
6
L
−
shell
L
−
shell
Fig. 6.10.
Plotsof(a)FLR-period
T
1
of the 1-st harmonics and (b) the half-width
δ
L
of the FLR-shells versus
L
. Panels (c) and (d) demonstrate, correspondingly,
dependencies of coecients
C
0
of (6.73), and coecient
Λ
0
of (6.116) on
L
different situations. In the first one,
T
is out of the FLR-band and in the
other one,
T
is within the FLR-band. It is obvious, that in this case the driver
excites FLR-oscillations of at least one FLR-shell.
Figure 6.11a (
) and Figure 6.11b ( arg
b
ϕ
) show azimuthal component
b
ϕ
in the equatorial magnetosphere plane as a function of the
L
-shell. The
solid lines correspond to the period of the driver
T
1
= 120 s, the dashed line -
T
2
= 160 s, and the dotted line -
T
3
= 180
.
2 s. Three horizontal dot-lines in
Fig. 6.10a show the L-shell dependencies of these periods. It is clear from Fig.
6.10a that each of periods
T
1
and
T
2
correspond two magnetic shells. The
shells
L
=3
.
35 and 3
.
90 most closely correspond to
T
1
and
L
=3
.
72 and 3
.
88
correspond to
T
2
.Theperiod
T
3
exceeds slightly the maximal FLR-period
180 s, at
L
=3
.
83.
In
|
b
ϕ
|
, there are two maxima between
L
=3and
L
=4foreachof
T
1
and
T
2
(solid and dashed lines in Fig. 6.10a). There is a minimum between
the FLR-shells. The ratio of minimal amplitude to maximal amplitude is sig-
nificantly lower for
T
1
compared to the same ratio for
T
2
. The amplitude
minima are located near the southern edge of the plasmapause for both peri-
ods. From the conservation of the energy flux, it follows that the amplitude
∝
|
b
ϕ
(
L
)
|
c
1
/
2
A
T
1
(
L
)
−
1
/
2
. Hence, the minimal amplitude should be located near
the maximal FLR-period, i.e. at the southern edge of the plasmapause (see
Fig. 6.10a).
Let the driver period be a little less than the maximal FLR-period. Then
two FLR-shells approach and only one peak of
∝
remains in the merid-
ional distribution instead of two resonance maxima. In the opposite case, if
|
b
ϕ
(
L
)
|
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