NSWP: Can the Kink Instability Trigger Solar Energetic Events?

Northwest Research Associates, Incorporated, Seattle WA

Investigators

Abstract

The proposed work will consider one candidate mechanism, the magnetic kink instability, as a trigger for solar eruptive events. This instability describes the rapid conversion of the "twist" component of magnetic helicity (the winding of the field lines about an axis) into "writhe" (winding of the axis itself). The PI asserted that recent observational studies concluding that active regions have insufficient magnetic twist to enable the kink instability have suffered from systematically underestimating the twist. The proposers offered here a new observational method with different assumptions, and stated that initial blind tests indicated that this method could successfully recover the twist known to be present in numerical simulations. The proposed new method will give a clearer indication of the role of the kink instability by improving upon the recent studies that have ruled out the kink instability based on what the proposers considered to be inappropriate assumptions. The results of this study will aid in determining which mechanism(s) gives rise to solar energetic events. The proposed work will identify flux ropes and evaluate their twist for a significant number of active regions, using vector magnetic field data in both the photosphere and chromosphere. The project goal will be to examine whether the kink instability can play a role in solar energetic events; the focus will be on establishing the necessary rather than the sufficient conditions for the occurrence of this mechanism in the Sun. For broader impacts, the vector magnetic field data used in this study, both photospheric and chromospheric, will be made available to the solar research community. The proposers will advise a graduate student from the Air Force Institute of Technology, as well as continue their ongoing public outreach programs and the mentoring of young women.