Observations of Thomson Scattering from a Loop-prominence System

Abstract We describe observations of the white-light structures in low corona following X8.2 flare SOL 2017-09-10, as observed full Stokes parameters by Helioseismic and Magnetic Imager (HMI) Solar Dynamics Observatory. These data show both bright loops a diffuse emission region above them. interpret counterpart classical loop-prominence system, intermediate between hot X-ray coronal rain. The external to is linearly polarized has natural interpretation terms Thomson scattering from plasma seen prior its cooling recombination. polarimetric HMI enable us distinguish this contribution pseudocontinuum measurement, make direct estimation mass source. For snapshot at 16:19 UT, we estimate 8 × 10 14 g. further conclude that volumetric filling factor source near unity.