skip to main content

SciTech ConnectSciTech Connect

Title: Kink instability evidenced by analyzing the leg rotation of a filament

Kink instability is a possible mechanism for solar filament eruption. However, it is very difficult to directly measure the twist of the solar filament from observation. In this paper, we measured the twist of a solar filament by analyzing its leg rotation. An inverse S-shaped filament in the active region NOAA 11485 was observed by the Atmospheric Imaging Assembly of the Solar Dynamics Observatory on 2012 May 22. During its eruption, the leg of the filament exhibited a significant rotation motion. The 304 Å images were used to uncurl the circles, the centers of which are the axis of the filament's leg. The result shows that the leg of the filament rotated up to about 510° (about 2.83π) around the axis of the filament within 23 minutes. The maximal rotation speed reached 100 degrees/minute (about 379.9 km s{sup –1} at radius 18''), which is the fastest rotation speed reported. We also calculated the decay index along the polarity inversion line in this active region and found that the decline of the overlying field with height is not fast enough to trigger the torus instability. According to the kink instability condition, this indicates that the kink instability is the trigger mechanismmore » for the solar filament eruption.« less
Authors:
; ; ; ;  [1] ;  [2] ;  [3]
  1. Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011 (China)
  2. Department of Physics, Shijiazhuang University, Shijiazhuang 050035 (China)
  3. Key Laboratory of Modern Astronomy and Astrophysics (Nanjing University), Ministry of Education, Nanjing 210093 (China)
Publication Date:
OSTI Identifier:
22351451
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 782; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; DECAY; ERUPTION; FILAMENTS; IMAGES; KINK INSTABILITY; ROTATION; SUN; VELOCITY