Dynamic evolution of the vortices in a filament and a prominence

¹ School of Physics and Optoelectronic Engineering, Anhui University, Hefei 230601, China
² Beijing Planetarium, Beijing Academy of Science and Technology, Beijing 100044, China

^⋆ Corresponding author: zjun@ahu.edu.cn, dtaoahu@qq.com

Received: 12 December 2024
Accepted: 29 April 2025

Abstract

Context. Although vortices have been observed in the solar atmosphere over the past few decades, vortices within the fine structures of solar filaments (prominences) have rarely been reported.

Aims. This report is to study the vortices inside the fine structures of a filament (case 1) and a prominence (case 2), and to reveal the dynamic evolution of these vortices.

Methods. Based on multi-wavelength observations from the New Vacuum Solar Telescope (NVST) and the Solar Dynamics Observatory, we tracked the evolution of the vortices inside the fine structures of the filament and the prominence by using the technique of the differential affine velocity estimator.

Results. In case 1, we detected a clockwise vortex within the spine of a filament in the southwest of the solar disc on 3 June 2023. The average projection speeds of the vortex in the NVST Hα line and the Atmospheric Imaging Assembly (AIA) 171 Å wavelength were 1.16 ± 0.09 km s⁻¹ and 4.30 ± 0.91 km s⁻¹, respectively. In case 2, a counterclockwise single vortex first appeared within a prominence on 6 September 2023 at the northwestern limb of the Sun, with average projection speeds of 2.56 ± 0.03 km s⁻¹ and 2.86 ± 0.76 km s⁻¹ in the NVST Hα and AIA 193 Å observations, separately. Then, several plumes were observed and intruded into the early single vortex. Subsequently, this single vortex split into three vortices.

Conclusions. We suggest that the internal kink instability may contribute to the formation of the single vortex in both cases. The intrusions of the plumes in case 2 possibly perturb the magnetic field of the single vortex and thus lead to its split. These results imply that the upward disturbance from the lower atmosphere can significantly change the structure and kinematic characteristics of the upper atmosphere.