Simultaneous Existence of Oscillations, Counterstreaming Flows, and Mass Injections in Solar Quiescent Prominences

Abstract

Solar prominences are very spectacular structures embedded in the tenuous and hot solar corona. Counterstreaming flows, a common feature in solar quiescent prominences, have been discovered for more than 20 yr. However, the mechanism driving the counterstreaming flows is still elusive. To unveil the nature of this phenomenon, we analyzed data of a quiescent prominence observed by the New Vacuum Solar Telescope, the Interface Region Imaging Spectrograph, and the Solar Dynamical Observatory. It is found that there is a distinct longitudinal oscillation of prominence plasma along the higher part of the prominence spine in Hα observations. The oscillation period is approximately 83 minutes and the amplitude is about 32 Mm. The counterstreaming flows are dominant in the middle part of the prominence spine. The velocities of the counterstreaming flows range from about 4 to 11 km s^‑1. Moreover, intermittent mass flows with upward plumes from the top of the bubbles and tornado-like barbs are observed to be injected into the lower part of the prominence spine from the lower atmosphere. The velocities of these injected mass flows range from about 3 to 30 km s^‑1. Some injected mass flows exhibit redshifted Doppler signals, while others exhibit blueshifted signals. Based on these high-resolution observations, it is found that different parts of the prominence spine exhibit different dynamic characteristics. These results further advance the understanding of the ubiquitous counterstreaming flows in solar quiescent prominences.