Using Observations to Elucidate the Magnetic Structure of Erupting and Non-Erupting Filaments

Artep Incorporated, Ellicott City MD

Investigators

Abstract

This investigation addresses the connection between coronal mass ejections (CMEs) and magnetic structures at the solar surface. Given the motivation that CMEs are recognized as the primary solar driver of non-recurrent geomagnetic storms, the Principal Investigator (PI) will focus on a comprehensive study of the structure, formation, and eruption of solar filaments, which are a basic component of most CME eruptions. Among other tasks, the PI will use high-cadence magnetograms and the application of a Local Correlation Tracking numerical code to determine photospheric flows in the vicinity of the polarity inversion line during the formation of a filament channel. She will then identify the locations of magnetic flux cancellation, coalescence, or fragmentation. She will test the hypothesis that filament barbs are jet-like flows triggered by magnetic flux elements that cross the filament channel and cancel with majority-polarity flux on the other side. The PI also will perform a systematic survey of endpoint brightenings in erupting quiescent and active-region filaments, employing spacecraft observations in order to verify that these features occur at the outer edges of transient holes (and are distinct from the well-known footpoint brightenings associated with post-eruption arcades). Finally, using spacecraft data, she will carry out a systematic study of rotation in erupting filaments, in order to test the hypothesis that a filament/barb system has the opposite helicity sign to the overlying arcade, contrary to the standard flux-rope model for filaments. The PI expects this study to lead to a better understanding of the underlying physical drivers of space weather. To enhance this broader impact, the PI will work closely with colleagues at the U.S. Naval Research Laboratory, who are actively involved in developing new operational techniques and instrumentation for space weather prediction for the U.S. Department of Defense.