Abstract
The present Letter is aimed at the study of properties of the current and magnetic shear in solar active regions. The distribution of the magnetic shear and current provides information on the nonpotentiality of solar flare-producing regions. We propose a rate factor R = shear magnitude/helicity magnitude, which is an index of the deviation from the chiralical magnetic field. As an example, NOAA Active Region 6659 has been analyzed, which was a large δ magnetic configuration in 1991 June. It is found that the shear and gradient of the magnetic field are important and reflect a part of the electric current in solar active regions, which is notable in the vicinity of the magnetic neutral line, while the total current in the active region is mainly contributed by the helicity; i.e., it relates mainly with force-free equilibrium.
Published Version (Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have