Investigation of Prominence Oscillations with High-Resolution Observations from the New Vacuum Solar Telescope

In this paper, we investigate the thread oscillations in a quiescent prominence observed by New Vacuum Solar Telescope at the Hα line center on 17 April 2024. Each individual thread is traced by the local maximum intensity on the time–distance maps. Although there are numerous threads in this prominence, 24 oscillating threads are identified at eight slits parallel to the solar surface. A sinusoidal function is used to fit them, and about 1.5 cycles of oscillations and a mean period of 27.7 min are detected. We find that all these 24 threads display the oscillation with almost a constant amplitude with an average value of about 0.92 Mm, with no damping or expansion during their lifetimes. Furthermore, we find the oscillations at different positions on a same thread almost have a similar period of 88.7 min in phase, which indicates that the thread oscillations could be triggered by a standing-type wave. Using the typical parameters in the prominence, the magnetic field strength (B) is estimated in the range of 4 G ≤ B ≤ 21 G, which is consistent with the previous results. Our findings would provide the clues for the thread oscillation mechanism in the prominence.