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arXiv · 2312.00673

The Automatic Identification and Tracking of Coronal Flux Ropes -- Part II: New Mathematical Morphology-based Flux Rope Extraction Method and Deflection Analysis

Andreas Wagner·Slava Bourgeois·Emilia K. J. Kilpua·Ranadeep Sarkar·Daniel J. Price·Anshu Kumari·Jens Pomoell·Stefaan Poedts·Teresa Barata·Robertus Erdélyi·Orlando Oliveira·Ricardo Gafeira
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Abstract

We present a magnetic flux rope (FR) extraction tool for solar coronal magnetic field modelling data, which builds upon the methodology from Wagner et al. (2023). We apply the scheme to magnetic field simulations of active regions AR12473 and AR11176. We compare the method to its predecessor and study the 3D movement of the newly extracted FRs up to heights of 200 and 300 Mm, respectively. The extraction method is based on the twist parameter and a variety of mathematical morphology algorithms, including the opening transform and the morphological gradient. We highlight the differences between the methods by investigating the circularity of the FRs in the plane we extract from. The simulations for the active regions are carried out with a time-dependent data-driven magnetofrictional model (TMFM; Pomoell et al. (2019)). We investigate the FR trajectories by tracking their apex throughout the full simulation time span. We demonstrate that this upgraded methodology provides the user with more tools and less a-priori assumptions about the FR shape that, in turn, leads to a more accurate set of field lines. The propagation analysis yields that the erupting FR from AR12473 showcases stronger dynamics than the AR11176 FR and a significant deflection during its ascent through the domain. The AR11176 FR appears more stable, though there still is a notable deflection. This confirms that at these low coronal heights, FRs do undergo significant changes in the direction of their propagation even for less dynamic cases. The modelling results are also verified with observations, with AR12473 being indeed dynamic and eruptive, while AR11176 only features an eruption outside of our simulation time window.

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Andreas Wagner, Slava Bourgeois, Emilia K. J. Kilpua, Ranadeep Sarkar, Daniel J. Price, Anshu Kumari, Jens Pomoell, Stefaan Poedts, Teresa Barata, Robertus Erdélyi, Orlando Oliveira, Ricardo Gafeira. 2023-12-01. The Automatic Identification and Tracking of Coronal Flux Ropes -- Part II: New Mathematical Morphology-based Flux Rope Extraction Method and Deflection Analysis. https://arxiv.org/abs/2312.00673

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