Measurements of Coronal and Chromospheric Magnetic Fields using Polarization Observations by the Nobeyama Radioheliograph

摘要: Coronal and chromospheric magnetic fields are derived from polarization spectral observations of the thermal free-free emission using Nobeyama Radioheliograph (NoRH). In magnetized plasma, ordinary extraordinary modes have different optical depths. This creates a circularly polarized component in an atmosphere with temperature gradient. We observed active region on April 13, 2012 to derive its coronal fields. The degree circular was between 0.5 % 1.7 %. radio images were compared ultraviolet by Atmospheric Imaging Assembly photospheric field Helioseismic Magnetic Imager, both board Solar Dynamic Observatory. At edge region, emitted mainly loops, be about 70 G. center components cannot separated. is 20 50 corresponding field, which emission-measure-weighted average