Solar magnetized tornadoes: rotational motion in a tornado-like prominence
Su, Y.1,
Gömöry, P.2,
Veronig, A.M.1,
Temmer, M.1,
Wang, T.3,4,
Vanninathan, K.1,
Gan, W.5,
Li, Y.P.5
1 IGAM-Kanzelhohe Observatory, Institute of Physics, University of Graz, Universitatsplatz 5, A-8010 Graz, Austria
2 Astronomical Institute of the Slovak Academy of Sciences, SK-05960 Tatranska Lomnica, Slovakia
3 Department of Physics, the Catholic University of America, Washington, DC 20064, USA
4 Solar Physics Laboratory (Code 671), Heliophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
5 Key Laboratory of Dark Matter and Space Astronomy, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008, China
Abstract:
Su et al. proposed a new explanation for filament formation and eruption, where filament barbs are rotating
magnetic structures driven by underlying vortices on the surface. Such structures have been noticed as tornado-like
prominences when they appear above the limb. They may play a key role as the source of plasma and twist in
filaments. However, no observations have successfully distinguished rotational motion of the magnetic structures
in tornado-like prominences from other motions such as oscillation and counter-streaming plasma flows. Here we
report evidence of rotational motions in a tornado-like prominence. The spectroscopic observations in two coronal
lines were obtained from a specifically designed Hinode/EIS observing program. The data revealed the existence
of both cold and million-degree-hot plasma in the prominence leg, supporting the so-called prominence-corona
transition region. The opposite velocities at the two sides of the prominence and their persistent time evolution,
together with the periodic motions evident in SDO/AIA dark structures, indicate a rotational motion of both cold
and hot plasma with a speed of ~5 km/s.