Sarah Gibson

Name Sarah Gibson
AffiliationNCAR/HAO, USA
TitleCoronal Magnetic Field Measurements and Models
AuthorsSarah Gibson
AbstractThe coronal magnetic field is fundamental to our understanding of solar and heliospheric structure and dynamics, but remains a difficult quantity to observe spectropolarimetrically. In the infrared (IR), proof-of-concept measurements of circular polarization have diagnosed line-of-sight magnetic field strength, and multiple years of synoptic linear-polarization observations have demonstrated capability for diagnosing topology of coronal structures. From these it is clear that the advent of larger-aperture telescopes, including the Daniel K. Inouye Solar Telescope (DKIST) and the Coronal Solar Magnetism Observatory (COSMO), will open a new window on our understanding of coronal magnetic fields. The upcoming VELC instrument on board the Aditya satellite will also obtain linear polarization measurements in the IR from space for the first time. An intriguing possibility would be to complement these existing and planned ground- and space-based IR measurements with space-based spectropolarimetric measurements in the ultraviolet (UV). Here the magnetic Hanle effect is unsaturated, resulting in different sensitivities to magnetic field direction and strength than in the infrared. By combining forward models of IR and UV spectropolarimetry with a variety of idealized coronal physical state models, including magnetic flux ropes, pseudostreamers, and streamer-solar wind interfaces, we consider the relative sensitivities of these diagnostics to coronal magnetic structure and strength, and, in particular, non-potentiality.