Dynamics evolution of a solar active-region filament from quasi-static state to eruption: rolling motion, untwisting motion, material transfer, and chirality

TL;DR

This study analyzes the dynamic evolution of a solar active-region filament from a quasi-static state to eruption, revealing rolling and untwisting motions, material transfer, and magnetic structure changes using high-resolution solar observations.

Contribution

It provides detailed observational insights into the filament's motion, magnetic reconnection, and structural evolution during eruption, highlighting the formation of twisted magnetic structures.

Findings

Filament F2 exhibited rolling motion before eruption.

Untwisting motion was observed during eruption.

Material transfer occurred via magnetic reconnection.

Abstract

To better understand magnetic structure and eruptive process of solar filaments, a solar active-region filament (labeled F2) eruption associated with a B-class flare was investigated by using high-resolution H$\alpha$ data from the 1 m New Vacuum Solar Telescope (NVST), combined with EUV observations of the Solar Dynamical Observatory (SDO). The filament F2 was disturbed by another filament (labeled F1) eruption that experienced a whip-like motion. Before the filament F2 eruption, the Dopplergrams show that the southern and the northern parts of the filament F2 body exhibit blueshift and redshift along the filament spine, simultaneously. It implies that the filament F2 was rolling from one side to the other. During the filament F2 eruption, the Doppler velocity shifts of the filament body are opposite to that before its eruption. It demonstrates that the filament body exhibits an untwisting motion, which can be also identified by tracing the movement of the eruptive filament threads. Moreover, it is found that the material of the filament F2 was transferred to the surrounding magnetic field loops, which is caused by magnetic reconnection between the filament F2 and the surrounding magnetic loops. According to the right-bearing threads of the filament F2 before its eruption, it can be deduced that the filament F2 is initially supported by a sheared arcade. The following observations reveal that the twisted magnetic structure of the filament F2 formed in the eruption phase.