| FORMATION AND ERUPTION OF AN ACTIVE REGION SIGMOID. I. A STUDY BY NONLINEAR FORCE-FREE FIELD MODELING | |
| Jiang, Chaowei; Wu, S. T.; Feng, Xueshang; Hu, Qiang; Jiang, CW (reprint author), Chinese Acad Sci, SIGMA Weather Grp, State Key Lab Space Weather, Ctr Space Sci & Appl Res, Beijing 100190, Peoples R China. | |
| Department | 空间科学部 |
| Source Publication | ASTROPHYSICAL JOURNAL
 |
| 2014 | |
| Volume | 780Issue:1Pages:55 |
| ISSN | 0004-637X |
| Language | 英语 |
| Keyword | Magnetohydrodynamics (Mhd) Methods: Numerical Sun: Corona Sun: Coronal Mass Ejections (Cmes) Sun: Flares Sun: Magnetic Fields |
| Abstract | We present a comprehensive study of the formation and eruption of an active region (AR) sigmoid in AR 11283. To follow the quasi-static evolution of the coronal magnetic field, we reconstruct a time sequence of static fields using a recently developed nonlinear force-free field model constrained by vector magnetograms. A detailed analysis of the fields compared with observations suggests the following scenario for the evolution of the region. Initially, a new bipole emerges into the negative polarity of a preexisting bipolar AR, forming a null-point topology between the two flux systems. A weakly twisted flux rope (FR) is then built up slowly in the embedded core region, largely through flux cancellation, forming a bald patch separatrix surface (BPSS). The FR grows gradually until its axis runs into a torus instability (TI) domain, and the BPSS also develops a full S-shape. The combined effects of the TI-driven expansion of the FR and the line tying at the BP tear the FR into two parts with the upper portion freely expelled and the lower portion remaining behind the postflare arcades. This process dynamically perturbs the BPSS and results in the enhanced heating of the sigmoid and the rope. The accelerated expansion of the upper-portion rope strongly pushes its envelope flux near the null point and triggers breakout reconnection at the null, which further drives the eruption. We discuss the important implications of these results for the formation and disruption of the sigmoid region with an FR. |
| Indexed By | SCI |
| Funding Project | 中国科学院空间科学与应用研究中心 |
| Document Type | 期刊论文 |
| Identifier | http://ir.nssc.ac.cn/handle/122/1502 |
| Collection | 空间科学部 |
| Corresponding Author | Jiang, CW (reprint author), Chinese Acad Sci, SIGMA Weather Grp, State Key Lab Space Weather, Ctr Space Sci & Appl Res, Beijing 100190, Peoples R China. |
| Recommended Citation GB/T 7714 | Jiang, Chaowei,Wu, S. T.,Feng, Xueshang,et al. FORMATION AND ERUPTION OF AN ACTIVE REGION SIGMOID. I. A STUDY BY NONLINEAR FORCE-FREE FIELD MODELING[J]. ASTROPHYSICAL JOURNAL,2014,780(1):55. |
| APA | Jiang, Chaowei,Wu, S. T.,Feng, Xueshang,Hu, Qiang,&Jiang, CW .(2014).FORMATION AND ERUPTION OF AN ACTIVE REGION SIGMOID. I. A STUDY BY NONLINEAR FORCE-FREE FIELD MODELING.ASTROPHYSICAL JOURNAL,780(1),55. |
| MLA | Jiang, Chaowei,et al."FORMATION AND ERUPTION OF AN ACTIVE REGION SIGMOID. I. A STUDY BY NONLINEAR FORCE-FREE FIELD MODELING".ASTROPHYSICAL JOURNAL 780.1(2014):55. |
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| 2014780155.pdf（7128KB） | 开放获取 | CC BY-NC-SA | View Download | |||
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