スライド 1

Jet Phenomena in the Solar Atmosphere with Rotational
Eruption or Spinning Motion;
Observation associated with Our MHD numerical Simulations
2004年4月12日
宮腰剛広
Jets associated with Rotating Eruption or Spinning Motion
Observations
•Kurokawa et al. 1987, Solar Phys., 108, 251
•Canfield et al. 1996, Apj, 464, 1016
•Pike and MASON, 1998, Solar Phys., 182, 333
•Alexander and Fletcher, 1999, Solar Phys., 190, 167
Theory
•Shibata and Uchida, 1986, Solar Phys.
magnetic twist packet propagates open coronal fields
The mass in the high density twisted loop is driven put into the open flux tube
due to both pinch effect and JXB force at the front of the packet.
Hot core (by pinch effect) and Cool sheath (unwinding front of the magnetic
twist) is formed.
Ha -5.0A
NOAA 4474, 23 April 1984
A, B: delta type sunspots
p: preceding
f: following
activity:
A>>B
Ha +-0A
22:35 / 23, Apr
Ap: westward motion
Bf : eastward motion
(motion with emergence)
C, Af: not clear motion
22:05 / 24, Apr
neutral
line
filament
(fig2,a)
AFS : Ap and Bf (opposite
polarities)
B: filament normal to neutral line
weak shear
A: filament parallel to neutral line
strong shear
Two X class flares on A:
04 UT on 24 Apr
00 UT on 25 Apr
B: no strong flare
Ha center
X13:
00 UT on 25 Apr
(a) pre flare
(b) great two ribbon flare
occurred
(b)(c) helically twisted
structure
(c)(d) helical twists are
gradually untwisted
(e) started to spout up of
untwisting rotation
(f) filament is hardly visible
in Ha line center
... but erupting process is clearly seen
in Ha wing
The curling fine structures of the
filament indicate unwinding
rotational motion of the spouting
material along the axis of the
filament.
velocitygrams
Ha +-1.0 or +- 0.8
with the photographic subtraction method
(Leighton et al. 1962)
white: the velocity toward the observer
black: the velocity away from us
EF : erupting filament
PFL : downward motions in the
post-flare loops
EF: left part, black
right part, white
clear separation indicates the rotating
motion around the spouting axis of the
filament
The direction of the rotation coincides
with that of the detwisting of the helical
twist found in Figure 4.
EF
SE : secondary eruption
my left the chromosphere around
00:43 UT
microwave absorption was observed
00:50 – 00:58 at TRO (Enome 1985);
good temporal coincidence
the second ejection extended along
the line S in Figure 7 and absorbed
the microwave radiation emitted by the
sunspots and post-flare loops
the velocity of the erupting filament
projected to the sky plane:
120 km/s
rotational : 50km/s (Figure 6)
50 km/s (rotation) must be larger than
the line-of-sight component of the ascending
velocity. Otherwise, the clear separation
of black and white along the filament axis
cannot be seen so clearly in the velocitygrams
120:
projection to the sky
rising
120/tan(shita)<50,
shita>68
120
rising filament almost normal
to the line-of-sight
shita
50
shita
line of sight
50
from side
R : NRO (Figure 7) moving type IV bursts, 200-830 km/s (Figure 8)
angle between R and P is small (<15 deg), so directly compared in Figure 8
It is obvious that the moving type IV burst is closely connected to the erupting
filament cloud.
21:38, 25/Apr
neutral
line
22:07, 24/Apr
two hours before the flare
filament normal neutral
weak shear
filament // neutral
strong shear
twisted
F: nearly parallel
T: large angle
Observed characteristics
agree well with those derived
from the simulation of Shibata
and Uchida (1986)
Yohkoh and Mees
NOAA 7260, 1992 Aug 19-20
The 23:11 UT Event
footpoint:
saturated
P0a
Contour: SXT, image: Mees, Ha
Yohkoh SXT
Expanded image of the
footpoint
it consists of two loops
upper and lower parts often
have different brightness
only this time is saturated
F: footpoints
L: interfootpoint regions
The light curves of these regions are
significantly different.
These images and light curves show
that the flaring X-ray structure consists
of two loops that are contiguous, end
to end.
surge
bright point (Ha)
SXT loop
SXT contour
grayscale: IVM magnetogram
-, weaker field
no spot
+, near satellite
-, near the moving satellite
spots
polarity
inversion
line
Ha blue
Ha red
23:11:30
Ha center
Ha velocity
contours reveal the
location of the 23:11
surge due to its
rotational motion
angular rate:
10^-3 rad/s,
lasting 1000 s
SXT
the spin is
right handed
(all the surges
in table 1)
six of nine surge/jet
events show highly
localized Ha downflow
at a bright point at the
base of the surge, and
eight of nine events show
that the surge is located
over the outer loop
downflow region is located at the base of the surge
It is at the north footpoint of the north loop, i.e., the footpoint farthest from p0a
fig6 area
stage 1: blueshifts gradually
develop. Ha gradually brightens
although no-Xray brightening
supports that this is Doppler
brightening.
Ha center
SXT
(maximum value)
stage 2: Ha brightens dramatically
and X-ray emission begins to increase.
stage 3: X-rays peak and a strong
redshift appears and peaks with
a delay of about 1 minute with respect
to the time of peak blueshift.
(surge base downflow motion)
The 18:34 UT event
in contrast to the previous event, it appears to occur in a plane that is considerably
inclined to the line of sight.
figure 9 area
Ha surge
X-ray
not cospatial
X-ray Jet
Ha
(fig8 box)
period A: two small penumbral
filaments
one is more curved than the other
The end of the one rears up in a
whiplike manner, while the other
remains in place.
Period B: two brightenings
approach one another (20 km/s)
This converging footpoints phenomenon
has not reported before.
period C: A blueshifted (dark) linear structure
appears in all images, moving from right to
left along a path parallel to the penumbral
filament that showed whiplike motion in strip
A. The measured transverse speed of
propagation of the blueshift region averages
25 km/s, peaks 120 km/s
Ha line center
black: blue shift
white: red shift
The bipole associated
with the moving satellite
spots and Ha penubbral
filaments
strong heating begins
Ha surges above X-ray
jet
downward
cool plasma moves,
caused Doppler
beightenings in Ha
weak reconnection,
(bit strongly heated)
reconnection
between
open fields
and strongly
twisted bipole
loops
(Shibata &
Uchida 1986)
The observed a: 0.4/Mm (Leka et al. 1994)
length of filaments: l~20Mm,
stored twist is several radians.
strong of twist is enough
10^-3 radian times 10^3 s equal 1 radian.
moving blueshift with whiplike motions
conversing footpoints
•Alexander and Fletcher, 1999, Solar Phys., 190, 167
TRACE observation
Vy component
z
z
y
x
x
Vy （紙面垂直速度成分）
赤：＋
青：－
Vy
+
(コロナアルフベン速度の
約10%ぐらい)
emerging flux region

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