The solar corona contains sheared or twisted magnetic fields overlying polarity inversion lines on the photosphere. The sheared/twisted fields can be observed as filament channels on the disk and as coronal cavities in limb observations; solar prominences are located within these regions. These structures warrant investigation because of their role in prominence eruptions, coronal mass ejections (CMEs), and solar flares. Understanding the topology and evolution of the prominence/cavity magnetic field structure prior to the eruption is key to understanding the onset of solar eruptions. To understand how filaments are supported, we will study the fine structure and dynamics of the observed filament as well as its relation with the corresponding photospheric magnetic fields, and the corresponding structure of the coronal magnetic fields will be reconstructed using photospheric magnetic field observations.
Tornado-like prominences were first described by Pettit (1932) but have not been paid much attention thereafter. Recently, several groups (e.g., Su et al. 2012; Wedemeyer-Boehm et al. 2012) observed Āgmagnetic tornadoesĀh with the AIA instrument onboard SDO, and pointed at possible connections among vortex motion on the surface, filament barbs, and solar tornadoes. However, whether these magnetic structures are indeed rotating, is a key question to be answered. Through cooperative observations between BBSO/NST, Hinode, and IRIS, and SDO we aim to address the following questions: what is the nature of the plasma dynamics in prominence barbs or tornado-like prominence? Do these motions play an important role in the formation and evolution of prominences? What is the relation between prominence barbs and tornado-like prominences? What is the magnetic structure supporting this type of prominence/filament?
Therefore, our primary target is a quiescent filament/prominence with barbs and/or tornado-like features. In the ideal case, we propose to track the filament from disk to west limb.
In case no suitable quiescent filament is available, our target will be changed to an active region with filaments.
In case of active region filaments, we can run observations similar to HOP 260.