Magnetic Flux Rope Identification and Characterization from Observationally Driven Solar Coronal Models

Abstract

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The Minimal Helicity of Solar Coronal Magnetic Fields

“…Our mean H is roughly ten times the helicity of a typical interplanetary magnetic cloud (Démoulin et al 2016), although the Halloween 2003 event was estimated to remove as much as 2 × 10 44 Mx 2 from the Sun (Lynch et al 2005). In a magneto-frictional model, Lowder & Yeates (2017) found that erupting flux ropes removed, on average, 2.6×10 43 Mx 2 , a more substantial fraction of H in the model.…”

Hemispheric injection of magnetic helicity by surface flux transport

“…From the viewpoint of the heliosphere, Bieber & Rust (1995) estimated a helicity ejection rate of 2 × 10 45 Mx 2 through coronal mass ejections by considering toroidal magnetic flux, while DeVore (2000) gave a higher estimate of 10 46 Mx 2 by modelling the magnetic structure of interplanetary magnetic clouds. More recently, Démoulin et al (2016) extrapolated data from 107 observed magnetic clouds to estimate a total ejection rate of 2.5×10 46 Mx 2 over solar cycle 23, and a similar value was obtained independently by Lowder & Yeates (2017) through non-potential modelling of flux rope formation and ejection in the low corona.…”

Forward Modeling of Coronal Mass Ejection Flux Ropes in the Inner Heliosphere with 3DCORE

“…The current three open parameters in the model should be based on CME statistics and other more sophisticated physical modeling regarding the origin, expansion, and propagation of CMEs. The initial flux and helicity content of the flux rope may be set by examining the preeruptive state of the flux rope with coronal magnetic field modeling (e.g., Lowder & Yeates, ; Yeates, ) The circular cross section and global shape also limit the current model applicability, which will be changed to different shapes such as ellipses or other deformed shapes (e.g., Hidalgo et al, ; Janvier et al, ; Möstl et al, ; Owens, ) in future updates.…”