Presentation #328.03 in the session “Solar Physics Division (SPD): Simulations, Magnetic Fields, and Coronal Structure and Heating”.
Observing the global coronal magnetic field remains a difficult task; limiting our understanding of the evolution of global phenomena in these external layers of the solar atmosphere. Therefore, we rely on models to get the solar exterior global field. While models can extrapolate the magnetic field from surface flux and vector magnetogram observations, e.g. by assuming a current-free corona, other techniques are used to simulate the current-carrying field via magnetohydrodynamic (MHD) evolution or surface flux transport of large scale field, and inserting current-carrying small scale field structures like twisted flux ropes into the corona. These current-carrying fields are of interest for studying solar energetic eruptions like coronal mass ejections and flares because they provide the energy reservoir needed to drive these events. Previous studies suggest that ground-based infrared polarimetric measurements of Fe XIII (1074.7 nm) line correlate with the energy of the current-carrying field. In this study we generated synthetic polarimetric observations from a fully-resolved magnetohydrodynamics model of the August 21, 2017 eclipse. The synthetic observations were used as input to a diagnostic we developed to identify regions where the modeling team inserted twisted flux ropes. The diagnostic evaluated linearly and circularly polarized synthetic observations of the corona as a means to identify the current-carrying magnetic energy density. We found that the diagnostic does identify the distribution of flux ropes in the corona. Thus, our findings motivate the implementation of polarimetric measurements to identify “hot spots” in which we can insert flux ropes and a degree of the twist/shear in the current-carrying field.