2020/06/26 by Rui Zhu, Baolin Tan, Zhu, Rui +13
Biochemistry, Genetics and Molecular Biology · Physics and Astronomy · #FOS: Physical sciences #Geomagnetism and Paleomagnetism Studies #Magnetic confinement fusion research #Solar and Space Plasma Dynamics #Solar and Stellar Astrophysics (astro-ph.SR) #astro-ph.SR
paper · pdf · doi:10.48550/arxiv.2006.15014
openalex publication_date 2020/06/26 · arxiv created 2020/06/29 · arxiv updated 2020/06/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We have performed microwave diagnostics of the magnetic field strengths in solar flare loops based on the theory of gyrosynchrotron emission. From Nobeyama Radioheliograph observations of three flare events at 17 and 34 GHz, we obtained the degree of circular polarization and the spectral index of microwave flux density, which were then used to map the magnetic field strengths in post-flare loops. Our results show that the magnetic field strength typically decreases from ~800 G near the loop footpoints to ~100 G at a height of 10--25 Mm. Comparison of our results with magnetic field modeling using a flux rope insertion method is also discussed. Our study demonstrates the potential of microwave imaging observations, even at only two frequencies, in diagnosing the coronal magnetic field of flaring regions.