Based mainly on the high-resolution data obtained by the one-meter New Vacuum Solar Telescope (NVST) at the Fuxian Solar Observatory of Yunnan Observatories, Chinese Academy of Sciences (CAS), Dr. WANG Jincheng et al. investigates the formation process of an active-region filament. The result has been published recently in Monthly Notices of the Royal Astronomical Society.

How the solar filament format is still unclear in the solar physics.The authors mainly focus on the material supply for the formation of the filament. The NVST captured the whole feeding process of a solar filament. They estimate the plasma mass uploaded by the jets and the mass of the filament, which supports the fact that the mass carried by the jets can supply sufficient material for the formation of the filament.

The significant finding is that some cool jets seen in the Hα band but not seen in EUV bands could also eject the cool material for the filament formation. These results suggest that cool plasma in the low atmosphere can be directly injected into the upper atmosphere by cool or hot jets, feeding the filament. Moreover, the newly emerging flux with the non-potential field plays an important role in the appearance of the jets and the magnetic structure of the filament.

This finding may open a new window for understanding the material supply of the filament. Some filament material could come from the accumulation of the cool plasma carried by ubiquitous small explosive events in the low atmosphere. These small explosive events also would carry the cool plasma to filament height, not just some big explosive events.

Contact

WANG Jincheng, YNAO, CAS

wangjincheng@ynao.ac.cn