E-Print Archive

There are 3950 abstracts currently viewable.


Search:

Advanced Search
Options
Main Page Add New E-Print Submitter
Information
Feedback
News Help/FAQ About Preferences
Manage Key Phrase
Notification
Block-induced complex structures building the flare-productive solar active region 12673 View all abstracts by submitter

Shuhong Yang   Submitted: 2017-10-18 18:26

Solar active region (AR) 12673 produced 4 X-class, 27 M-class, and numerous lower class flares during its passage across the visible solar disk in September 2017. Our study is to answer the questions why this AR was so flare-productive and how the X9.3 flare, the largest one of the last decade, took place. We find that there was a sunspot in the initial several days, and then two bipolar regions emerged nearby it successively. Due to the standing of the pre-existing sunspot, the movement of the bipoles was blocked, while the pre-existing sunspot maintained its quasi-circular shaped umbra only with the disappearance of a part of penumbra. Thus, the bipolar patches were significantly distorted, and the opposite polarities formed two semi-circular shaped structures. After that, two sequences of new bipolar regions emerged within the narrow semi-circular zone, and the bipolar patches separated along the curved channel. The new bipoles sheared and interacted with the previous ones, forming a complex topological system, during which numerous flares occurred. At the highly sheared region, a great deal of free energy was accumulated. On September 6, one negative patch near the polarity inversion line began to rapidly rotate and shear with the surrounding positive fields, and consequently the X9.3 flare erupted. Our results reveal that the block-induced complex structures built the flare-productive AR and the X9.3 flare was triggered by an erupting filament due to the kink instability. To better illustrate this process, a block-induced eruption model is proposed for the first time.

Authors: Shuhong Yang, Jun Zhang, Xiaoshuai Zhu, Qiao Song
Projects: GOES X-rays,SDO-AIA,SDO-HMI

Publication Status: Accepted for publication in ApJL
Last Modified: 2017-10-18 20:42
Go to main E-Print page  High-wavenumber solar f-mode strengthening prior to active region formation  Reconstruction of a Large-scale Pre-flare Coronal Current Sheet Associated with an Homologous X-shaped Flare  Edit Entry  Download Preprint  Delete Entry 

Key
Go to main E-Print pageGo to main E-Print page.
Previous AbstractPrevious Abstract.
Next AbstractNext Abstract.
Download PreprintDownload Preprint.
Submitter's HomepageSubmitters Homepage.
Edit EntryEdit Entry.
View All Abstracts By SubmitterView all abstracts by submitter.
Delete AbstractDelete abstract.

Latest Entries
Frequency rising sub-THz emission from solar flare ribbons
Particle acceleration in coalescent and squashed magnetic islands I. Test particle approach
Statistical Analysis of Torus and Kink Instabilities in Solar Eruptions
Solar Eruptions, Forbush Decreases and Geomagnetic Disturbances from Outstanding Active Region 12673
Coronal hard X-ray sources revisited
Manifestations of bright points observed in G-band and Ca II H by Hinode/SOT
Propagation of Leaky MHD Waves at Discontinuities with Tilted Magnetic Field
Time variations of the non-potential and volume-threading magnetic helicities
Advances in mean-field dynamo theory and applications to astrophysical turbulence
Reverse Current Model for Coronal Mass Ejection Cavity Formation
Predictions of DKIST/DL-NIRSP Observations for an Off-limb Kink-unstable Coronal Loop
Exploring the biases of a new method based on minimum variance for interplanetary magnetic clouds
The non-modal onset of the tearing instability
SpatioTemporal Evolution and North-South Asymmetry of Quasi-Biennial Oscillations in the Coronal Fe XIV Emission
Corotating Shock Waves and the Solar-Wind Source of Energetic Ion Abundances: Power Laws in A/Q
Coronal condensations caused by magnetic reconnection between solar coronal loops
Measurement of Vector Magnetic Field in a Flare kernel with a Spectropolarimetric Observation in He I 10830 A
The Relation Between Escape and Scattering Times of Energetic Particles in a Turbulent Magnetized Plasma: Application to Solar Flares
Implications of loop-top origin for microwave, hard X-ray, and low-energy gamma-ray emissions from behind the limb flares
Solar radio emission as a disturbance of aeronautical radionavigation

Related Pages
MSU Solar Physics.
Max Millennium Science Mail Archive.
Max Millennium Message of the Day Mail Archive.
Max Millennium Flare Catalog

Archive Maintainer
Alisdair Davey



© 2003 Solar Physics Group - Montana State University