Simultaneous transverse and longitudinal oscillations in a quiescent prominence triggered by a coronal jet

Abstract

In this paper, we report our multiwavelength observations of the simultaneous transverse and longitudinal oscillations in a quiescent prominence on 2015 June 29. A C2.4 flare took place in active region 12373, which was associated with a pair of short ribbons and a remote ribbon. During the impulsive phase of the flare, a coronal jet spurted out of the primary flare site and propagated in the northwest direction at an apparent speed of $\sim$224 km s$^{-1}$. Part of the jet stopped near the remote ribbon. The remaining part continued moving forward before stopping to the east of prominence. Once the jet encountered the prominence, it pushed the prominence to oscillate periodically. The transverse oscillation of the eastern part (EP) of prominence can be divided into two phases. In phase I, the initial amplitude, velocity, period, and damping timescale are $\sim$4.5 Mm, $\sim$20 km s$^{-1}$, $\sim$25 minutes, and $\sim$7.5 hr, respectively. In phase II, the initial amplitude increases to $\sim$11.3 Mm while the initial velocity halves to $\sim$10 km s$^{-1}$. The period increases by a factor of $\sim$3.5. The western part (WP) of prominence also experienced transverse oscillation. The initial amplitude is only $\sim$2 Mm and the velocity is less than 10 km s$^{-1}$. The period ($\sim$27 minutes) is slightly longer than that of EP in phase I. To the east of prominence, a handful of horizontal threads experienced longitudinal oscillation. The initial amplitude, velocity, period, and damping timescale are $\sim$52 Mm, $\sim$50 km s$^{-1}$, $\sim$99 minutes, and 2.5 hr, respectively. To our knowledge, this is the first report of simultaneous transverse and longitudinal prominence oscillations triggered by a coronal jet.