Multiwavelength Study of Magnetic

Reconnection Associated with

Sigmoid Eruption

Chang Liu

BBSO/NJIT 20080401

BBSO/NJIT 2/14

I.I. A brief summary of 2005 May 13 M8 eventA brief summary of 2005 May 13 M8 event

II.II. Ongoing Study: A successive flaring event Ongoing Study: A successive flaring event (X1.5 + X1.4 + M9) on 2005 September 13 (X1.5 + X1.4 + M9) on 2005 September 13 with an emphasis on a high speed plasma with an emphasis on a high speed plasma flow between flaring regionsflow between flaring regions

OutlineOutline

BBSO/NJIT 3/14

Three Trigger Mechanism forLarge, Fast CME

Moore & Sterling (2006)

BBSO/NJIT 4/14

I. 2005 May 13 M8 Flare: A Comprehensive View

1st evidences of internal tether-cutting as trigger; Ribbon-like HXRs; Spatial SHS

behavior of HXR; Anticorrelation of vB field and HXR spectral index

(ApJ 658-L127; 664-L127; 669-1372; 672-L69)

BBSO/NJIT 5/14

Future EffortCan NLFF extrapolation model the preflare sigmoid

and postflare arcade fields, towards a better understanding of tether-cutting reconnection?

BBSO/NJIT 6/14

II. Successive Flaring on 2005 September 13

βγδ

• Partial sigmoid eruption: only eastern part of the overall sigmoid is involved• Long-duration event (~100 min) with multiple SXR peaks

Disk event in AR 10808

BBSO/NJIT 7/14

X1.5X1.4

M9

weak type II burst associated with filament eruption

Event tempora

levolutio

n

I II

Positively drifting features I and II, signifying downward propagating plasmoid

broadbandtype IIId burst signifies the beginning of impulsive phase of X1.4

OVSAOVSA

GBSRBSGBSRBS

X1.5 + X1.4 + M9Triple Flares

BBSO/NJIT 8/14

High Speed Plasma Flows:

from SE towards NW X1.4 flare at the main δ spot

speed as high as ~350 km/s, co-temporal

with starting of nonthermal

peaks

BBSO/NJIT 9/14

The flows are toward a coronal HXR source over the compact X1.4 flare at

δ spotHα kernels

Looptop HXR source

footpoint HXR source

Hα + HXR (blue wing; 25-50 keV)

Flow path

The looptop HXR source is present for ~10 minutes from ~19:54 UT, during which the flows are seen.

BBSO/NJIT 10/14

One possible scenario, but…

Shibata et al. 1995

BBSO/NJIT 11/14

(cont.) Flows in Hα: brighten at the northern end, and

possibly trigger the following M8 flare identified as

running kernels A & B

ABBB AB AB

BBSO/NJIT 12/14

M9 Flare

Hα + HXR (blue wing; 25-50 keV)

B A

BBSO/NJIT 13/14

Another speculation of

Flaring Scenario

M9X1.4

BBSO/NJIT 14/14

Future Effort

1. NLFF extrapolation to aid identifying flux systems that lead to these three successive flares. Hope it will help to pin down the nature of the flows (e.g, along field line or not).

2. OVSA radio imaging to further help map out the energy release steps of the events