理論面からの検討：	
  エネルギー蓄積からフレアトリガまで	
 鳥海	
 森（国立天文台）	
  	
  フレア検討チーム	
  清水敏文、渡辺恭子、浅井歩、伴場由美、草野完也、塩田大幸	
 	
 
	
  

シンポジウム「スペース太陽物理学の将来展望」	
  (2014	
  Oct.	
  21)	
 
	
  

836

MOORE ET AL.

Vol. 552

1.	
  フレア理論	  ìフレア・CME理論モデル	
  ì

数多く存在	
  l

L98
Tether-­‐cu5ng	
  model:	
  Moore	  et	
  al.	  (2001)	
  Filament	
  formaAon:	
  van	  Ballegooijen	
  &	  Martens	  (1989)	
  Filament	
  erupAon:	
  Chen	  &	
  Shibata	
  (2000)	
  

l

Flux	
  cancellaAon	
  model:	
  Linker	
  et	
  al.	  (2003)	
  l

Reversed	
  shear	
  model:	
  Kusano	
  et	
  al.	  (2004)	
  Kink	
  instability:	
  Török	  &	
  Kliem	
  (2005)	
  Torus	
  instability:	
  Fan	  &	
  Gibson	  (2007)	
  
etc.	
  

l
l

l
l
l

ì

1974

Phys. Plasmas, Vol. 10, No. 5, May 2003

TÖRÖK & K

Tether-­‐cu5ng	
  model:	  Moore	  et	
  al.	  (2001)	
  FIG. 1.ÈOur version of the standard model for the magnetic Ðeld explosion in single-bipole eruptive solar events (from Moore 2000). This version is
tailored to bipoles having sigmoidally sheared and twisted core Ðelds and accommodates conÐned explosions as well as ejective explosions. The rudiments ofthe Ðeld conÐguration are shown before, during, and after the onset of an explosion that is unleashed by internal tether-cutting reconnection. The dashedcurve is the photospheric neutral line, the dividing line between the two opposite-polarity domains of the bipoleÏs magnetic roots. The ragged arc in the
background is the chromospheric limb. The gray areas are bright patches or ribbons of Ñare emission in the chromosphere at the feet of reconnected Ðeldlines, Ðeld lines that we would expect to see illuminated in SXT images. The diagonally lined feature above the neutral line in the top left panel is the Ðlamentof chromospheric temperature plasma that is often present in sheared core Ðelds.

Ñow in to reconnect at the rising reconnection site. (Forother depictions of this three-dimensional implosion/
explosion process, in basically the same closed sheared conÐguration but from other perspectives, see Figs. 1, 2, and 3of Moore, LaRosa, & Orwig 1995.) In this picture, thereconnection is expected to produce most of the particle
acceleration and plasma heating that result in the Ñareburst of electromagnetic radiation across the spectrum fromradio waves to hard X-rays or c-rays (as Moore et al. 1995
have shown to be feasible in terms of the sheared core Ðeld,Ñare ribbon development, and number of energetic electrons required for the hard X-ray burst observed in a large
ejective Ñare). The eruption onset panel in Figure 1 depicts
this explosive release early on when the heating ÐrstLinker et al.

becomes strong enough to initiate the brightening of theÑare ribbons in the chromosphere and the rise of the soft
X-ray burst. In this early stage of the explosion, if we arelucky enough to have SXT coverage, as the sigmoid brightens in the X-ray images we might also see the two productsof the reconnection : the upward released Ñux rope andcompact brightening under the middle of the sigmoid.
Once the runaway reconnection begins, there are two
possibilities for how the explosion plays out. Either the
explosion ejects the erupting Ñux rope out of the initiallyclosed bipole, opening the envelope Ðeld (Fig. 1, lower rightpanel), or the explosion is arrested and conÐned within theclosed bipole (Fig. 1, lower left panel). What determines
which path the explosion takes is an unanswered question.

Flux	
  cancellaAon	
  model:	  Linker	  et	
  al.	  (2003)	
  関連する観測も多数	
  instability:	
  Fig. 1.—Left: TRACE 195Kink	
  Å imagesof the confined filament eruption on
2002 May 27. Right: Magnetic
field
lines
outlining
the core of the kink-unstable
Török	
  
&
	
  
K
liem	
  
(2005)	
  flux rope (with start points in the bottom plane at circles of radius b/3) att p 0, 24, and 37. The central part of the box (a volume of size 43) is shown,and the magnetogram, Bz(x, y, 0, t), is included.

i
s
a
w
T
t

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s

i

1.	
  フレア理論	  ìフレア・CME理論モデル	
  ì

共通理解：基礎過程として	  フラックスロープ形成	
 

不安定化	
 

フラックスロープ放出	
  
↑↓	
  
磁気リコネクション	
  1.	
  フレア理論	  ìフレア・CME理論モデル	
  ì

共通理解：基礎過程として	  フラックスロープ形成	
 

不安定化	
 

フラックスロープ放出	
  
↑↓	
  
磁気リコネクション	
  1.	
  フレア理論	  ìフレア・CME理論モデル	
  ì

共通理解：基礎過程として	  フラックスロープ形成	
 

不安定化	
 

フラックスロープ放出	
  
↑↓	
  
磁気リコネクション	
  1.	
  フレア理論	  ìフレア・CME理論モデル	
  ì

共通理解：基礎過程として	  フラックスロープ形成	
 

不安定化	
 

フラックスロープ放出	
  
↑↓	
  
磁気リコネクション	  •問題は「いつ・何が系を不安定化させるのか？」	
  •不安定化させる要因（＝フレアトリガ）に関する研究は不十分	  •研究はあまり多くないら
しい：see,	  e.g,	
  Forbes	  (2000)	
  and	
  Schrijver	
  (2009)	
 1.	
  フレア理論	  ìフレアトリガ研究	  ìì

コロナアーケード中に局所磁場構造が出現→フレア発生	
  低層大気における磁気リコネ
クションによってフラックス
ロープが形成	  大局的な磁場構造	
  （コロナアーケード）	
 局所的な磁場構造	  （フレアトリガ磁場）	
 Kusano	  et	
  al.	  (2012)	
  1.	
  フレア理論	  フレアトリガ研究	
  
ì
ì

ì

コロナアーケード中に局所磁
The Astrophysical Journal, 760:31 (9pp), 2012 November 20
場構造が出現→フレア発生	
  低層大気における磁気リコネ
クションによってフラックス
ロープが形成	  トリガ磁場の方位角に依存	
  大局的な磁場構造	
  （コロナアーケード）	
 アーケード磁場のシア角	  ìFigure 2. Summary of simulations for Be = 2, re = 0.13, τe = 20, ve = 6.7 × 10−3 , ye = 0 on parameter space of ϕe and θ0 . Different marks (represent the types of dynamics, and contours show the maximum total kinetic energy produced by eruption (Ek ). Squares indicate that no er
the corresponding parameter; diamonds indicate the appearance of eruptions at each parameter. Pink and blue diamonds indicate eruption-ind
reconnection-induced eruption processes, respectively. The yellow diamond corresponds to a special case in which the potential field collapses b
with the small-scale injected field, which exhibits a completely antiparallel polarity compared with the initial potential field. The right-hand an
the initial sheared field and orientation of injected small bipole field, respectively, in which white and black areas indicate positive and negati
represent the horizontal component of the magnetic field.

トリガ磁場の方位角	
  局所的な磁場構造	  （フレアトリガ磁場）	
 Kusano	  et	
  al.	  (2012)	
  We detected a clear difference in the morphologies of magnetic fields between cases triggered by OP- and RS-type con-Figures 4(a)–(c)) and forms a current sheet (reby c in Figure 4(b)) on the border between

1.	
  フレア理論	  ìフレアトリガ研究	  The Astrophysical Journal, 773:128 (10pp), 2013 August 20(a)
13:10 UT

P2

Kusano	  et	
  al.	  (2012)	
  

13:22 UT

13:34 UT

13:46 UT

N1

13:58 UT

14:10 UT

14:22 UT

14:34 UT

14:46 UT

14:58 UT

15:10 UT

15:22 UT

Toriumi	  et	
  al.	  (2013)	
  (b)gure 7. Onset processes for solar flares in AR NOAA 11158 observed by Hinode/SOT. The gray scale (black, negative; white, positive) represents the Stokes-V/I
nal in the Na i 5896 Å line. Red contours indicate the emission of the Ca ii H line, and green lines represent the polarity inversion line (PIL). Observation times areown for each subset. The subset at the lower right corner of (b) illustrates the typical RS structure with counterclockwise rotating sheared field.

UTì 15:00
AR	
  11158の詳細な観測	
  topology of the magnetic field. In both scenarios, flare
5. DISCUSSION AND CONCLUSIONl AR	
  11158	
  Mthe
フレアにおけるl コロナアーケード：数日・数万km	
  reconnection
on a vertical current sheet is caused by thediverging flows that remove magnetic flux and plasma from the
The results shown in the previous section indicate thatのスケール	
  reconnection site. This mechanism corresponds to the “pull”
ents indeed occurred that are described by トリガ磁場を「特定」	
  the following two

ì

観測との比較	  mode in reconnection experiments performed in laboratories(Yamada 1999). As shown in Figure 8, two different types ofdivergent flows are able to form a thin current sheet v between
two sheared magnetic loops B1 and B2 . One divergent flow is avertical (upward) flow above the PIL (u in Figure 8) and the otherenarios: scenario 1 involves an eruption-induced reconnection
ocess triggered by an OP-type magnetic field, and scenario 2
a reconnection-induced eruption process triggered by an
S-type magnetic field. Here, we examine the reason fore existence of both scenarios. It is explicable in terms ofl

トリガ磁場：5000	
  km程度	
  
7

N1

l
トリガ磁場：数10分・1000	
  km以下P2の要素が合体して形成	
  Figure 6. (a) HMI vector magnetogram during 13:10–15:22 UT. The gray scaleshows the longitudinal field, while sky-blue bars indicate the transverse field.
Here, the direction of the transverse fields is not indicated. Red and blue linesc.f.	
  Bamba	
  et	
  al.	  (2013)	
  

w
a

h
b
a
a
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fi
i
v
t
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l

r
c
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I
1
(

1.	
  フレア理論	
  
ì

まとめ	
  

フラックスロープ形成	
 •フラックスロープ	
  
数日、数万	  km	  スケール	  •フレア条件	  (Hagyard	
  1990)	
  
PIL	
  ≧	
  10	
  Mm,	
  shear	  ≧	
  80°	
 不安定化	
 フラックスロープ放出	
  
↑↓	
  
磁気リコネクション	  •トリガ磁場	  •5000	
  km程度、数時間	
  
ただし	
  
1000	
  km以下、数10分	
  	
 の構造が集合・合体	 すべてのスケールがフレア発生に重要	
 2.1.	
  取得データとその解釈	
  ì

RMHD計算・インバージョン	  ì

RMHD計算は「必須」	
  Bifrostコードの導入	
  or	
  国産モデル開発	
  

ì

ì

•

輸入が楽ではある	  彩層スペクトルの複雑さ：IRISデータから	
  静穏領域はBifrostモデルと比較できそう	  ì 活動領域・リコネクション・フレアは再現困難か	
  
ì

•

通常のEBスペクトル	
  (Mg	
  II	
  k)	
 

•

Bifrostでどの程度再現可能か？	
  •Bifrostを用いて、そもそもSolar-­‐Cで
彩層磁場等が観測可能か事前に調べる必要あり	  • “異常”	  なEBスペクトル	  →	
  シングルピークなら	
  VD	
  =	
  -­‐100	
  km	
  s-­‐1	 The Astrophysical Journal Letters, 788:L2 (6pp), 2014 June 10

The Astrophysical Journal Letters, 788:L2 (6pp), 2014 June 10

2.1.	
  取得データとその解釈	
  ì

Archontis & Hansteen

(a)

(a)

(b)

(b)

RMHD計算・インバージョン	  ìBifrost計算の例：ダイナミックな現象の計算は少ない（難しい）	
  
The Astrophysical Journal, 736:9 (12pp), 2011 July 20

Martı́nez-Sykora, Hansteen, & Moreno-Insertis

(c)

(d)

(d)

(e)

Figure 4. (a) Intermittent heating (isosurfaces
with
T ! 5.5of×vertical
105 K;
red) uat asthefunction
interface
and the log(Terupting
plasmoids (isosurfaces of ρ ≈ 10−12 g cm−3 ; blue) at
Figure3. Distribution
velocityoftemperature)z(g)t = 8800 s. The (black) arrows show the directionof thealong
thet =fieldhorizontal
slice is the Bz distribution at z =(h)3.14 Mm, demonstrating thatin the vicinityof thefieldspiculeat time1930lines.
s.√
AlsoTheshownwith gray markers
is thedistributionof the speed
soundcs =aroundγ P /ρ theat theplasmoid,same time. whichThe
the heating occurs between opposite polarity
fields.
(b) Close-up
ofoftheregionis outlined by frame A in panel (a). The B-field vector
spiculeis supersonichas(yellow;
temperaturesin therange from15,000K(arrows) shows the highly sheared field acrosstheplasmainterface.
Field and
lines
blue
belongto theinteracting
loops) reconnect and a fast jet is emitted underneathto some few 105 K at this time in the evolution of the spicule.
the erupting plasmoid (twisted field lines, white)
and above the flare loops (lower white field lines). (c) Two-dimensional vertical cut at the interface (y = 5.6 Mm)showing J 2 /B 2 . Time is t = 8850 s. (d) Close-up of the temperature isosurfaces (framed at inset (B), panel (a)). The cusp-shaped reconnected field lines (in yellow)
show the topology of the post-flare loops. Thelinestheindicate
length ofsmall two-ribbon
flare.
anddashedincludingjet as athefunctionof thetemperature,along with√ofjournal.)
sound (cs = γ P /ρ). The velocities comprising(A color version of this figure is available inthe
thespeed
onlinethe jet are largely supersonic, with Mach numbers of order two
for the lowest
gas.Thisthe close vicinity of (at least) two plasmoids
intemperature
succession.
shows that there is a good spatial relationship between the sites
Close to the base of the jet we find a region where the Joule
implies that the eruption of one plasmoid
affect isorlarge,evenasinitiprofoundheating and the places with strong current. This
heating can
per particle
shown with of
the green
isosurface
ate the eruption of the others. Accordingly,flare
can occurs
changethatofthe
in Figure each
2. Joule
heatingalong theimplies
entire length
theintermittent heating is due to the fragmentation
but isstartstrongestin the first few
megametersbase. As acurrent layer.
the field line topology so that otherjet,sites
to reconnect
andofnearthetheinterfaceresultJoule heating,the nearby corona is heated,and hot4(d)loopsdisplays the lower part of the hot filaments
another flare is set off nearby. This
canofleadto “sympathetic”
Figurewith temperatures up to 1.6 MK are produced with temperature
flaring
activity
and,ultimately,toprofoundheatingandplasma(inverse
Y-shaped
temperature isosurfaces, T ! 5 × 105 K).
Figure 2. Structure of the type ii spicule and the related hot loop at t = 1850 s,much greater than that found in the ambient corona. These hotthetransition regionatin terms of the temperature at 1.3expulsion
106 K (red isosurface),aswe
discussed
earlier.
Reconnected
field
lines
form an arcade of loops. The overallloops are apparent through the red temperature isosurface. Note
105 K (orange isosurface), upflowing velocity along the field lines at 45 km s−1
that
the
hot
loops
have
one
footpoint
near
the
base
of
the
jet.
The
eruptionofplasmoids
evolvesintohelical
jets.
This
is
arcadeisnottheresultofa single eruptive flare, as has been
3
(blue isosurface), and Joule heating at 1 W/m (green isosurface). The field lines
Figure2. Evolution
acrossthe andinterfaceat x = 10.35 Mm. Times are t = 8530 s, t = 8750 s, and t =The hot
loops consistof low-density
material,
are associatedare drawn on opposite sides of themagnetic discontinuity
in redpurple. B4(b).
ypartially
illustrated
inand
FigureThe
upwardfast reconnection
previously
thought, but it consists of distinct, cusp-like, small−1(red/blue). Two plasmoids are outlined in panel (b). Arrows (panels (e) and (h))
with, but[−100,
separate100]
from,kmthe sjet proper.
at the photosphere is shown with a grey-scale map with a range of [−210, 210]
jettransition(red) consistsof thesome
twistedoftothenote
plasmoid
eruptive
G. Except in the spicule itself theregion is on average
2 Mm field lines
It is (white)
interestingthat (g)).
the magnetic
field is flares,
unipolarwhich show up as “miniature” version of bigger(z ≈ 4.7 Mm,
panel
above the photosphere.
on its upper part (at z ≈ 12 Mm).
Duringemission,
the jet; thisflares(e.g.,
Masuda et al. 1994; Tsuneta 1996, 1997). Twoin theregionthearoundthe modeledis alsothe case(An animation and a color versioneruptedof this figureplasmoids
is available in thecome
online journal.)(Ana colorversionthis
figureareon
available
online.)for manyobserved
type ambient
iiand
spicules(McIntosh&ofDe
Pontieu
into contact
withtheanimation“open”
brightribbonsform
either sideof the neutral line, joining2009). Even so,
we leads
find several
large gradients(non-twisted) magnetic field and reconnect.
This
to theregions withthe successive
footpoints of the post-flare loops. Thus, a cluster

MarAnez-­‐Sykora	
  et	
  al.	  (2011)	
  スピキュールの形成	
  ArchonAs	
  &	
  Hansteen	
  (2014)	
  「ナノ-­‐マイクロフレア」の再現	
  2.2.	
  フレア研究における観測との連携	
  ì

観測・運用との連携	
  ì

Solar-­‐Cの制約：テレメトリとの勝負	  1.

Solar-­‐Cの現行計画値	
  
•
FoV	
  :	
  180”	
  ×	
  180”	
  =	
  130	  Mm	  ×	
  130	  Mm	  •ResoluAon	
  :	
  0.1”	
  =	
  70	
  km	
  

2.

なるべく活動領域全体の発展を追いたい	
  3.

トリガ観測としては分解能	
  0.1”	
  は悪くない？	
  ケーデンスも考慮する必要あり	
  

4.
	
  

→

詳細な議論は伴場さん講演を参照	
  

	
  
ì

「1日前予報」の精度は現在とさほど変わらないのでは？	
  →	
  「数時間前予報」なら精度は向上するかも	
  

	
  

ì

トリガ的磁場はPIL周辺に多数存在	
  →	
  トリガの事前特定を可能にしておく必要性あり（次ページ）	
  

(a)

PIL

Y [pixels]

500
400
300

2.2.	
  フレア研究における観測との連携	
  100

Shear angle0(b) Reversed shear type

課題：詳細なトリガ研究	
  複数の「容疑者」？	
  500

実際の活動領域には多数のフレアトリ
ガ的な磁場構造が存在	
   PILì 観測視野が狭いため、事前にある程度
Azimuthal angle「容疑者の絞り込み」が必要	
  

400

ì

Figure 1. Schematic illustration of the two different types of flare onset
suggested by Kusano et al. (2012): (a) opposite polarity (OP) type and (b)reversed shear (RS) type. In both cases, coronal arcade fields lying over the PIL
and the local triggering field (emerging flux) are shown by thin curved arrows,
while photospheric magnetic fields are indicated by lighter (positive) and darker(negative) hatches. The shear angle of the overlying arcade and the azimuthal
angle of the triggering field are the parameters that characterize the magnetic
configuration. Both angles are measured counterclockwise from the axis normal
to the PIL (thick arrows).

ììY [pixels]ìIn this paper, we present a detailed event analysis of theM6.6ì
class複数トリガの導入	
  flare that occurred on 2011 February 13 in NOAAAR 11158, which was briefly reported in Kusano et al. (2012).
フルMHD下でのシミュレーション	  Here,ì
we useobservational data of this AR taken by multiple
spacecraft, along with the nonlinear force-free field (NLFFF)ì “リアリスティック”モデル	
  extrapolation and numerical results of a flare simulation. The
goals of this paper are to understand: (1) the overall development
magnetic fields in AR 11158 before the M6.6 flare, (2) theìof theひので観測の向上も必須	
  formation process of the flare-triggering region that initiates the
M flare, and (3) the evolution of the M flare in the main phase.
The rest of the paper proceeds as follows. In Section 2, we
introduce the observations of AR 11158 and the data reduction

200

400

600

800

1000

1200

Hinode/SOT Na Stokes-V/I 13-Feb-2011 17:30 UT
(b)

300
200
100
0
0

トリガリコネクションの発生高度？	
  シミュレーションの改良	
  

0

600

GOES SXR flux [W m-2 ]

ì

200

10-4

200

(c)

400

600
X [pixels]

800

1000

1200

M6.6

10-5
10-6
10-7
12:00

15:00
18:00
21:00
Start time: 13-Feb-2011 12:00 UT

00:00

Figure 2. M6.6 class flare in NOAA AR 11158. (a) Ca intensity map at 17:35 UT
and (b) Na Stokes-V/I image at 17:30 UT on 2011 February 13, observed byHinode/SOT. (c) GOES-15 soft X-ray flux in the 1.0–8.0 Å channel (1 minutecadence).
(A color version of this figure is available in the online journal.)

2.3.	
  成功基準とフレア予測の実践	  ì

Solar-­‐Cでのフレア研究に向けて	  ì

成功基準：何を目標とするか？	
  フレア領域の光球・彩層磁場測定	  ì エネルギー蓄積〜トリガ機構の物理解明	
  ì フレア発生時刻・場所の	
 事後	
 特定	
  
ì

ì

フレア発生時刻・場所の	
 直前〜同時	 特定	
  （＝準リアルタイム予報）	
  ì フレア発生時刻・場所の	
 事前	
 特定	
  
（＝フレア予報）	
  ì 地球近傍への影響の	
 事前	
 予測	
  
（＝宇宙天気予報）	
  （ミニマムサクセス）	
 フルサクセス	 フルサクセス	 エクストラサクセス	  • フレア数時間前の地上観測へのフィードバックを想定	
 エクストラサクセス	  • 1-­‐2日前予報によるSolar-­‐C運用
へのフィードバックを想定	  Solar-­‐Cでは厳しいか	
  • CME地球到達以前の「正確な」影響評価を想定	 2.3.	
  成功基準とフレア予測の実践	  ì

Solar-­‐Cでのフレア予測	  ì

やるべきか？	
  目指すべきではある	  ì 「フレア（直前・事前）予測」をエクストラサクセスとする場合、計画段階からそこに全軍投入して良いのか	
  
ì

l
ì

ì

観測→予測→運用フィードバック	
 は相応のコストがかかる	  理論・観測研究の進展やSolar-­‐C打ち上げ後の運用状況を見てから	  フレア補足率は向上するか？	
  現在の理論研究・観測研究や運用体制の改善でまだまだ出来るはず（希望）	
  ì 「今できる研究」を進めるべき	
  
ì

ì

フレア予測の実現可能性？	
  ì

正直、分からない	  ìフレア過程を完全に理解すれば予測・予報は実現するはず	
  3.	
  まとめ	  ì

現在までの理解：フレア理論	
  ì

エネルギー蓄積：コロナアーケード・フラックスロープ形成	
  
ì

ì

ì

数日、数万km	
  スケールの現象	
  トリガ過程：トリガ磁場発生	  ì

数1000	
  km、数時間程度の構造	
  

ì

1000	
  km以下、数10分スケールの微小磁場が関与している可能性あり	
  Solar-­‐Cのフレア研究	
  ミニマムサクセス：フレア磁場の測定（彩層含む）	
  ì フルサクセス：物理機構の解明	
  ì エクストラサクセス：事前予報（数時間前）	
  →	
  「予報」は物理を解明してから。物理を完全に解明すれば出来る	
  
ì

3.	
  まとめ	
  
ì

課題	
  
ì

RMHDコードとインバージョン	
  
ì

ì

RMHDはBifrost輸入が現実的か	  フレアトリガの事前特定	  草野シミュレーションの改良	  ì ひのでによるフレア補足率の向上	
  
ì

ì

Solar-­‐Cによるフレア観測の可能性	
  ì

Bifrostなどを活用し、	
  
l

浮上磁場	
  

l

リコネクション	
  

l

フレア	
  

	
 の彩層磁場等、観測可能性を検証	  Thank	  you	
  for	
  your	  attention!	
 	
  Appendix	  (a) Jet 1

ì

データ駆動型シミュレーション	  ì

シミュレーションの境界条件	
  ì 現状：光球の3次元磁場データを利用して上空の磁場を推定	  ì Cheung	
  et	
  al.	  (in	  prep)：ジェットを生じた周囲の磁場環境を再現、
IRIS観測と比較	
  ì

彩層観測のメリット	  ì 光球磁場・彩層磁場観測から磁場勾配を計算	  →	
  電流場を推定可能	  ì 密度・エネルギーフラックスなども観測できればシミュレーションの精度を向上できる	
  Homologous Helical(a) Bz at z = 0 Mm(c) Jet 3

Figure 5. Total intensity and mean Doppler velocity of the four jets as computefour jets, there is a tendency for northern edge to be blueshifted while the southe
four jets are helical with the same (negative) sign of kinetic helicity.

started to investigate how multiple jets can be emitted
from the same source region. From a 3D MHD simulation of flux emergence, Archontis et al. (2010) reported
that a series of reconnection events between the emerging flux system and ambient coronal field led to recurrent
jets. Moreno-Insertis & Galsgaard (2013) performed asimilar numerical experiment and found a succession of
eruptions, some of which have physical properties that
resembled the ‘standard’ type of jet while others wereminiature flux rope ejections that that may be associatedwith so-called blowout jets (Moore et al. 2010). WhileBz at z =(2013)
4 Mm paper mentions
the Moreno-Insertis &(b)Galsgaardthat the erupting flux ropes in the simulation seem to

Cheung	
  et	
  al.	  (2014,	
  in	
  prep)	
  rotate as
possible hstudied.
Recentl
performin
emergingfield. The
duction imechanisheated to
They repof plasma
Figur
spheric(withtoa statiflux ro