Two Solar Tornadoes Observed with the Interface Region Imaging Spectrograph
Two Solar Tornadoes Observed with the Interface Region Imaging Spectrograph
复制标题
用界面区域成像摄谱仪观测到的两次太阳龙卷风
DOI：
10.3847/1538-4357/aa9e04
复制
发表时间：
2018
影响因子：
4.9
通讯作者：
Chen Yajie
中科院分区：
文献类型：
--
作者：
Yang Zihao;Tian Hui;Peter Hardi;Su Yang;Samanta Tanmoy;Zhang Jingwen;Chen Yajie
The barbs or legs of some prominences show an apparent motion of rotation, which are often termed solar tornadoes. It is under debate whether the apparent motion is a real rotating motion, or caused by oscillations or counter-streaming flows. We present analysis results from spectroscopic observations of two tornadoes by the Interface Region Imaging Spectrograph. Each tornado was observed for more than 2.5 hr. Doppler velocities are derived through a single Gaussian fit to the Mg ii k 2796 Å and Si iv 1393 Å line profiles. We find coherent and stable redshifts and blueshifts adjacent to each other across the tornado axes, which appears to favor the interpretation of these tornadoes as rotating cool plasmas with temperatures of 104 K–105 K. This interpretation is further supported by simultaneous observations of the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory, which reveal periodic motions of dark structures in the tornadoes. Our results demonstrate that spectroscopic observations can provide key information to disentangle different physical processes in solar prominences.
