Dynamics of the Transition Corona
Abstract
Magnetic reconnection between open and closed magnetic field in the corona is believed to play a crucial role in the corona / heliosphere coupling. At large scale, the exchange of open /closed connectivity is expected to occur in pseudo-streamer structures. However, there is neither clear observational evidence of how such coupling occurs in pseudo-streamers, nor evidence for how the magnetic reconnection evolves. Using a newly-developed technique, we enhance the off-limb magnetic fine structures observed with AIA and identify a pseudo-streamer-like feature located close to the northern coronal hole. We first identify that the magnetic topology associated with the observation is a pseudo-streamer, null-point-related topology bounded by open field. We then compare the evolution of the observed pseudo- streamer fine structure in the location of strong currents, i.e. in the region of energy dissipation, with the dynamics of the magnetic field resulting from the interchange reconnection obtained in a fully 3D MHD simulation. The morphological and dynamical similarities between the pseudo-streamer observations and the results from the simulation strongly suggest that the evolution of the pseudo-streamer is caused by interchange reconnection in a null-point topology that is embedded in Quasi-Separatrix layers. Besides identifying the mechanism at work in the large-scale coupling between open and closed field, our results highlight that interchange reconnection in pseudo-streamers is a gradual physical process that differs from the impulsive reconnection of the solar-jet model.
- Publication:
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AAS/Solar Physics Division Abstracts #44
- Pub Date:
- July 2013
- Bibcode:
- 2013SPD....44...27M