Recently, Research in Astronomy and Astrophysics published the latest research work conducted by Dr. KANG Kaifeng and Prof. LIN Jun from Yunnan Observatories of the Chinese Academy of Sciences (CAS) and other collaborators. They investigated in detail the splitting process and eruption mechanism of a large-scale horse-shoe-like filament by using the high temporal and spatial resolution multi-wavelength observational data from the Optical and Near-infrared Solar Eruption Tracer (ONSET) and the Solar Dynamic Observatory (SDO).

Coronal mass ejections (CMEs) and solar flares are the most energetic eruptive phenomena in the solar system, and the main drivers of catastrophic space weather. Existing researches have shown that filament (also known as prominence) eruptions are closely associated with the occurrence of CMEs and flares. Therefore, careful and in-depth research on filament eruptions helps to understand and reveal the mechanism of solar eruptions, and construct the physical models for prediction of catastrophic space weather. It is often considered that a filament usually erupts as a whole. However, in recent years, an increasing number of observations have shown that filament can also undergo partial eruption, meaning that only a portion of the filament is expelled from the sun, while the other is left.

Through in-depth observational analysis on a large-scale horse-shoe-like filament, researchers found that the filament split before the eruption, and the pre-eruption splitting was caused by the reconnection between the filament’s magnetic field and newly emerging magnetic field. Following the split, the filament underwent a partial eruption. The filament partial eruption here presented new observational features that cannot be explained by the classic “double-decker filament” model nor the “partially-expelled flux-rope” model. Thus, this event provides new observational constraints on the construction of the new models for partial eruptions. Meanwhile, by analyzing the kinematics of the eruption process and calculating the decay index of the background magnetic fields, researchers suggest that catastrophe (or torus instability) is the eruption mechanism of the filament.

Contact:
LIN Jun
Yunnan Observatories, CAS
Email: linj@ynao.ac.cn