Poleward-moving auroral forms and dayside magnetic reconnection

• Main Authors: Robison, Audrey, Fasel, Gerard, Mann, John C
• Format: Text
• Language: unknown
• Published: Pepperdine Digital Commons 2021
• Subjects: Magnetic Reconnection; Poleward-moving Auroral Forms; The Sun and the Solar System; Longyearbyen; Svalbard
• Online Access: https://digitalcommons.pepperdine.edu/scursas/2021/session_d/4; https://digitalcommons.pepperdine.edu/context/scursas/article/1657/type/native/viewcontent

The solar-terrestrial interactions are not completely understood. Magnetic reconnection, which was first proposed by Dungey in 1961, is thought to be the most understood among these interactions. This process begins when the interplanetary magnetic field (IMF) merges with the geomagnetic field at the dayside magnetopause. Energetic particles travel down the magnetic field lines and interact with the neutral particles in the upper atmosphere, creating aurora in the northern and southern hemispheres. Poleward-moving auroral forms (PMAFs) were suggested to be the ionospheric signatures of magnetic reconnection at the dayside magnetopause (Vorobjev et al., 1975). This paper uses a new technique to analyze ground-based optical data from the Kjell Henriksen Observatory in Longyearbyen, Svalbard. Video from the all-sky color camera, Boreal Aurora Camera Constellation (BACC), is analyzed using this technique to demonstrate its ability to identify pre-existing auroral arcs. This imaging shows that there is a pre-existing auroral arc at the most poleward edge of the auroral oval. Before the onset of the PMAF, the pre-existing dayside auroral arc initially brightens before it begins to drift poleward. These results are different from past PMAF studies, in which the PMAFs appeared to move eastward/westward, depending on the IMF By–component, before drifting poleward into the polar cap. A statistical analysis of this study will also be included in this presentation.