Coronal Observations from the Inouye Solar Telescope: Initial Model Comparisons

As the largest coronagraphic solar polarimeter ever built, the Daniel K. Inouye Solar Telescope (DKIST) advances observations of the off-limb solar corona with a specific focus on infrared diagnostics of the coronal magnetic field. Here we discuss early results from the Cryogenic Near-Infrared Spectropolarimeter (Cryo-NIRSP) and highlight the first commissioning observations of all four of its prime spectral line targets: the Fe XIII 1075 nm, Fe XIII 1079 nm, Si X 1430 nm, and Si IX 3934 nm forbidden lines. The Si IX observations, in particular, significantly improve upon the few previous ground-based detections of this line and open up this diagnostic for more routine study. Using initial calibration strategies, we find favorable correspondence between the observations and available global MHD coronal models, which highlight the unique constraints provided by these radiative- and collisional-excited lines. We further present commissioning data of the Si X 1430 nm that consists of high spatial resolution (1”) polarized raster images of the solar corona, and discuss other early data acquired during commissioning and the ongoing operations commissioning phase.