Признаки стационарного магнитного пересоединения в...
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Признаки стационарного магнитного пересоединения в солнечном ветре Ю. Л. Сасунов, В. С. Семенов СС. Петербургский университет Thanks to N. Erkaev, M. Heyn, H. Biernat and I. Kubyshkin
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Признаки стационарного магнитного пересоединения в солнечном ветре. Ю. Л. Сасунов, В. С. Семенов С С. Петербургский университет. Thanks to N. Erkaev, M. Heyn, H. Biernat and I. Kubyshkin. Sites for reconnection in magnetosphere. “ Standard Model ” of Flares. - PowerPoint PPT Presentation
Transcript of Признаки стационарного магнитного пересоединения в...
Признаки стационарного магнитного пересоединения в
солнечном ветреЮ. Л. Сасунов, В. С. Семенов
СС. Петербургский университет
Thanks to N. Erkaev, M. Heyn,H. Biernat and I. Kubyshkin
Sites for reconnection in magnetosphere
“Standard Model” of Flares
Reconnection at the Leading Edge of an ICME
After J. Gosling
Results from Study of Initial 49 Exhausts Identified in the ACE 64-s Data (~1.3 events/month)
Most of the exhausts were associated with relatively large field shear angles.
Typical exhaust crossing times were 10 minutes - exhaust widths ~ 2.4 x 105 km.
After J. Gosling
This is the largest exhaust yet identified in the solar wind and demonstrates prolonged reconnection at an extended and continuous X-line.
Gosling et al., GRL 2007
Reconnection event 31.08 – 1.09.2001
Normal coordinates LMN
Riemann problem for reconnection
B a
C
S
S
A
B b
B n
A
A
(R)
(R )
S-
S-
C
Heyn, Biernat, Rijnbeek, and Semenov, The Structure of Reconnection Layers,J. Plasma Phys., 1988.
Decay of discontinuity
BV
S-
B a
C
S
S
A
B b
A
S
C
S AExhaust
B a
B b
A
S
C
S
A
Exhaust
B a
B b
Structure of reconnection layer
3-D view 2-D projection
Alfven discontinuityAlfven discontinuity
Shock waveShock wave
)1(
,8
0}{
0}{
0))}((41
)21
({
0}41
{
0)}(81
{
0}{
2
22
222
p
BpP
ãäå
VBVB
B
VBBBVVV
BBVV
BBVP
V
nttn
n
nnn
tntn
ntn
n
01
01
00101
011
)||)(sgn(
||
pp
VVbmBVV
BbB
AAnA
)1)(1(1)(
4
)1)(1(21
1
))(||)(sgn(
||
2
1
2
2
0
2
01002
012
G
BP
ãäå
GVbVmBVV
BbB
a
a
AAn
)(||)(||||
))(sgn(
||1
))(||)(sgn(
))(||)(sgn(
||||
~
0
~
0
00
~
00
~
~
0
~
10
~~
0
0100
0
~~
0
GVGVh
VVVVmBnh
hh
b
GVbVmBV
GVbVmBV
BB
AA
AA
AAn
AAn
0
)(
nB
tVnVnR nSW
Sat1
Sat2
Sat3
WindACEGeotail
0 1 2 3 4 5 6-100
0
100
Vx
0 1 2 3 4 5 6-100
0
100
Vy
0 1 2 3 4 5 6-50
0
50
Vz
0 1 2 3 4 5 6-10
0
10
Bx
0 1 2 3 4 5 6-5
0
5
By
0 1 2 3 4 5 6-5
0
5
Bz
0 1 2 3 4 5 60
2
4
AS C S A
Reconnection event on 31 Aug – 1 Sep 2001 (WIND)
Reconnection event on 31 Aug – 1 Sep 2001 (GEOTAIL)
0 1 2 3 4 5 6-200
0
200Vx
0 1 2 3 4 5 6-100
0
100
Vy
0 1 2 3 4 5 6-50
0
50
Vz
0 1 2 3 4 5 6-5
0
5
Bx
0 1 2 3 4 5 6-5
0
5
By
0 1 2 3 4 5 6-5
0
5
Bz
0 1 2 3 4 5 60
1
2
AS C AS
Reconnection event on 31 Aug – 1 Sep 2001 (ACE)
0 1 2 3 4 5 6-50
0
50Vx
0 1 2 3 4 5 6-100
0
100
Vy
0 1 2 3 4 5 6-50
0
50
Vz
0 1 2 3 4 5 6-5
0
5
Bx
0 1 2 3 4 5 6-5
0
5
By
0 1 2 3 4 5 6-5
0
5
Bz
0 1 2 3 4 52
4
6
AS C AS
Interaction of solar wind with ICME
With reconnectionafter Erkaev N. V.
No reconnection after Erkaev N. V.
Pudovkin and Bogdanova, Geomag. Aeronomy, 2002
Interaction of solar wind with ICME
Reconnection in the solar wind:
Occurs at thin current sheets that separate distinctly different plasma states (tangential discontinuities).
Commonly is quasi-stationary and typically occurs at extended X-lines (~390 Re Phan et al. 2006, ~600 Re Gosling et al. 2007)
Produces Petschek-type exhausts of roughly Alfvenic jetting plasma bounded by rotational discontinuity-slow shock structure that bifurcate the original thin current sheet.
Slows down ICMEs with low magnetic shear and accelerates ICMEs with high shear.
