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Multiwavelength Study of Magnetic Reconnection Associated with Sigmoid Eruption Chang Liu BBSO/NJIT 20080401. Outline. A brief summary of 2005 May 13 M8 event
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Multiwavelength Study of Magnetic Reconnection Associated withSigmoid EruptionChang LiuBBSO/NJIT 20080401
Outline • A brief summary of 2005 May 13 M8 event • Ongoing Study: A successive flaring event (X1.5 + X1.4 + M9) on 2005 September 13 with an emphasis on a high speed plasma flow between flaring regions
Three Trigger Mechanism forLarge, Fast CME Moore & Sterling (2006)
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)
Future Effort Can NLFF extrapolation model the preflare sigmoid and postflare arcade fields, towards a better understanding of tether-cutting reconnection?
II. Successive Flaring on 2005 September 13 βγδ Disk event in AR 10808 • Partial sigmoid eruption: only eastern part of the overall sigmoid is involved • Long-duration event (~100 min) with multiple SXR peaks
X1.5 X1.4 Event temporalevolution M9 X1.5 + X1.4 + M9 Triple Flares broadbandtype IIId burst signifies the beginning of impulsive phase of X1.4 OVSA Positively drifting features I and II, signifying downward propagating plasmoid I II GBSRBS weak type II burst associated with filament eruption
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
The flows are toward a coronal HXR source over the compact X1.4 flare at δ spot Hα+ HXR(blue wing; 25-50 keV) Hα kernels footpoint HXR source Looptop HXR source Flow path The looptop HXR source is present for ~10 minutes from ~19:54 UT, during which the flows are seen.
One possible scenario, but… Shibata et al. 1995
(cont.) Flows in Hα: brighten at the northern end, andpossibly trigger the following M8 flare identified asrunning kernels A & B B B B B B A A A
B A M9 Flare Hα+ HXR (blue wing; 25-50 keV)
Future Effort • 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). • OVSA radio imaging to further help map out the energy release steps of the events