Electric-Current Neutralization, Magnetic Shear, and Eruptive Activity in Solar Active Regions

Abstract

The physical conditions that determine whether or not solar active regions (ARs) produce strong flares and coronal mass ejections (CMEs) are not yet well understood. Here we investigate the association between electric-current neutralization, magnetic shear along polarity inversion lines (PILs), and eruptive activity in four ARs; two emerging and two well-developed ones. We find that the CME-producing ARs are characterized by a strongly non-neutralized total current, while the total current in the ARs that did not produce CMEs is almost perfectly neutralized. The difference in the PIL-shear between these two groups is much less pronounced, which suggests that the degree of current-neutralization may serve as a better proxy for assessing the ability of ARs to produce CMEs.

ApJL in press

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Cited by in corpus (4)

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• Very fast helicity injection leading to critically stable state and large eruptive activity in solar active region NOAA 12673
• Degree of electric current neutralization and the activity in solar Active Regions
• Formation and eruption of sigmoidal structure from a weak field region of NOAA 11942