Three-dimensional Velocity Fields of the Solar Filament Eruptions Detected by CHASE

Abstract

The eruption of solar filaments, also known as prominences appearing off limb, is a common phenomenon in the solar atmosphere. It ejects massive plasma and high-energy particles into interplanetary space, disturbing the solar-terrestrial environment. It is vital to obtain the three-dimensional velocity fields of erupting filaments for space-weather predictions. We derive the three-dimensional kinematics of an off-limb prominence and an on-disk filament, respectively, using the full-disk spectral and imaging data detected by the Chinese Hα Solar Explorer (CHASE). It is found that both the prominence and the filament experience a fast semicircle-shaped expansion at first. The prominence keeps propagating outward with an increasing velocity until escaping successfully, with the south leg of the prominence finally moving back to the Sun in a swirling manner. For the filament, the internal plasma falls back to the Sun in a counterclockwise rotation in the late ejection, matching the failed eruption without a coronal mass ejection. During the eruptions, both the prominence and the filament show material splitting along the line-of-sight direction, revealed by the bimodal Hα spectral profiles. For the prominence, the splitting begins at the top and gradually spreads to almost the whole prominence with a fast blueshift component and a slow redshift component. The material splitting in the filament is more fragmental. As shown by the present results, the CHASE full-disk spectroscopic observations make it possible to systematically study the three-dimensional kinematics of solar filament eruptions.

Comprehensive Analysis of a Filament-embedding Solar Active Region at Different Stages of Evolution

“…The reference line center was calculated in a quiet square region near the disk center. There are several other ways (see Qiu et al 2024 and references therein) to obtain the Doppler shift of Hα lines, and two general methods, i.e., the moment analysis and the bisector method, are adopted and confirm the Doppler velocity obtained here. The first one is to calculate the line core weighted-averaged by intensity as l = l å -S -…”

Broad and Bidirectional Narrow Quasiperiodic Fast-propagating Wave Trains Associated with a Filament-driven Halo Coronal Mass Ejection on 2023 April 21

“…The eruption coincided with a GOES M1.7 flare, a halo CME with a two-front morphology (see Figure 1(g); Liu et al 2019;Shen et al 2022a) and a series of QFP wave trains. The eruption process will be discussed in the following paper, using CHASE data, as its full-disk spectroscopic imaging has the advantage of investigating the 3D kinematics of solar filament eruptions (Qiu et al 2024).…”