Formation of a Coronal Hole by a quiet-Sun Filament Eruption

Stefan J. Hofmeister; Eleanna Asvestari; Karin Dissauer; Michael Hahn; Stephan G. Heinemann; Veronika Jercic; Alexandros Koukras; Kilian Krikova; Jonas Saqri; Daniel W. Savin; Manuela Temmer; Astrid Veronig

arXiv · 2509.04663

Formation of a Coronal Hole by a quiet-Sun Filament Eruption

Stefan J. Hofmeister·Eleanna Asvestari·Karin Dissauer·Michael Hahn·Stephan G. Heinemann·Veronika Jercic·Alexandros Koukras·Kilian Krikova·Jonas Saqri·Daniel W. Savin·Manuela Temmer·Astrid Veronig

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Abstract

A coronal hole formed as a result of a quiet-Sun filament eruption close to the solar disk center on 2014 June 25. We studied this formation using images from the Atmospheric Imaging Assembly (AIA), magnetograms from the Helioseismic and Magnetic Imager (HMI), and a differential emission measure (DEM) analysis derived from the AIA images. The coronal hole developed in three stages: (1) formation, (2) migration, and (3) stabilization. In the formation phase, the emission measure (EM) and temperature started to decrease six hours before the filament erupted. Then, the filament erupted and a large coronal dimming formed over the following three hours. Subsequently, in a phase lasting $15.5$~hours, the coronal dimming migrated by 150" from its formation site to a location where potential field source surface extrapolations indicate the presence of open magnetic field lines, marking the transition into a coronal hole. During this migration, the coronal hole drifted across quasi-stationary magnetic elements in the photosphere, implying the occurrence of magnetic interchange reconnection at the boundaries of the coronal hole. In the stabilization phase, the magnetic properties and area of the coronal hole became constant. The EM of the coronal hole decreased, which we interpret as a reduction in plasma density due to the onset of plasma outflow into interplanetary space. As the coronal hole rotated towards the solar limb, it merged with a nearby pre-existing coronal hole. At the next solar rotation, the coronal hole was still apparent, indicating a lifetime of >1 solar rotation.

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Stefan J. Hofmeister, Eleanna Asvestari, Karin Dissauer, Michael Hahn, Stephan G. Heinemann, Veronika Jercic, Alexandros Koukras, Kilian Krikova, Jonas Saqri, Daniel W. Savin, Manuela Temmer, Astrid Veronig. 2025-09-04. Formation of a Coronal Hole by a quiet-Sun Filament Eruption. https://arxiv.org/abs/2509.04663

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