Understanding the Role of Mass-Unloading in a Filament Eruption
Abstract
Solar filaments are persistent features on the solar surface, lasting from days to months before either successfully erupting into the heliosphere as part of a CME, or collapsing and returning the suspended plasma to the chromosphere. To date, the consensus has been that the plasma comprising the filament plays no significant role in the global evolution of the host flux rope. As a result, little effort has been made to quantify the impact that mass has on the evolution of magnetic structures in the solar atmosphere. Here we present observations and analysis that suggest that the inclusion of mass is an important next step to fully understand solar eruptions. A partial filament eruption that occurred on 11 December 2011 was observed by both the Solar Terrestrial Relations Observatory-Behind (STEREO-B) and the Solar Dynamics Observatory (SDO) spacecraft. The combination of multiple perspectives from different locations within the heliosphere allowed the removal of line-of-sight projection effects, and the correlation of plasma dynamics to the evolution in filament height. Our results show that 70\% of the measurable filament mass drained shortly \textit{prior} to a change in the height--time expansion profile of the remaining filament material from a shallow to steeper exponential. A proxy was then formulated to test whether the observed mass-unloading was responsible for this observed change in behaviour. This proxy is defined as the ratio between the upward force supplied to the host flux rope due to this mass-unloading and the restraining force caused by the tension of the overlying magnetic field. A ratio range of between 1.8 and 4.1 was found, indicating that the upward force as a result of the the mass-unloading dominated the evolution. We conclude that the unloading of filament mass from the host flux rope was likely responsible for the accelerated expansion.
- Publication:
-
2018 Triennial Earth-Sun Summit (TESS)
- Pub Date:
- May 2018
- Bibcode:
- 2018tess.conf10907J