New Vacuum Solar Telescope observations of a flux rope tracked by a filament activation

摘要

One main goal of the New Vacuum Solar Telescope (NVST) which is located atthe \emph{Fuxian Solar Observatory} is to image the Sun at high resolution.Based on the high spatial and temporal resolution NVST H$\alpha$ data andcombined with the simultaneous observations from the \emph{Solar DynamicsObservatory} for the first time, we investigate a flux rope tracked by afilament activation. The filament material is initially located at one end ofthe flux rope and fills in a section of the rope, and then the filament isactivated due to magnetic field cancellation. The activated filament rises andflows along helical threads, tracking out the twisted flux rope structure. Thelength of the flux rope is about 75 Mm, the average width of its individualthreads is 1.11 Mm, and the estimated twist is 1$\pi$. The flux rope appears asa dark structure in H$\alpha$ images, a partial dark and partial brightstructure in 304 {\AA}, while as bright structures in 171 {\AA} and 131 {\AA}images. During this process, the overlying coronal loops are quite steady sincethe filament is confined within the flux rope and does not erupt successfully.It seems that, for the event in this study, the filament is located andconfined within the flux rope threads, instead of being suspended in the dipsof twisted magnetic flux.