This collaborative observational and theoretical research proposal focuses on the formation, activation, and the long-term slow ascent of solar filaments prior to their eruption as Coronal Mass Ejections (CMEs). This team of six scientists from five institutions will use high- and medium-resolution data from ground-based telescopes (NSO's ISOON, DST, SOLIS, as well as Helio Research and the Swedish Solar telescopes) and space-borne instruments (SOHO's EIT, MDI, LASCO) in combination with theoretical analysis. The PI and her team will: (1) model the role of magnetic reconnection in the formation of filaments and their substructures known as "barbs;" (2) study the relationships of filament fine-structure to chromospheric structure and photospheric magnetic fields, in order to identify mass flows into and out of the main body of filaments at the highest available spatial resolution (0.5-0.15 arc sec); (3) model the ways that filaments and their barbs can experience local or full body accelerated mass motions (called "activations") and how the barbs detach from the chromosphere when destabilized under various conditions; (4) analyze existing sets of multi-wavelength Ha Doppler data to reveal the types of motions that occur during filament activations and the early stages of filament eruption; and (5) study the long-term slow rise of filaments as an early indicator of their destabilization and eruption.
A central theme for both of these theoretical and observational investigations is the long overlooked roles of barbs in the formation, evolution, activation, and eruption of filaments. The PI will also extend earlier preliminary studies indicating that filaments exhibit both systematic and sporadic increases in their overall height and in the velocities of their mass motions during several days preceding filament eruption. As part of the broader impacts, the modeling, analyses, and acquisition of new observations will involve at least one postdoc and at least six undergraduate students.
