2018/01/10 by Jürgen Hinterreiter, J. Hinterreiter, Astrid M. Veronig +7 · 27 citations
Engineering · Physics and Astronomy · #Electric field #Electrohydrodynamics and Fluid Dynamics #Field (mathematics) #Lightning and Electromagnetic Phenomena #Magnetic reconnection #Power Transformer Diagnostics and Insulation #Ribbon #Solar flare #Solar physics #Solar prominence #astro-ph.SR
paper · pdf · doi:10.1007/s11207-018-1253-1
published in Solar Physics 293(3), 38 (Springer Science+Business Media) · 26 pages, 14 figures, 2 tables, accepted for publication in Solar Physics
arxiv created 2018/01/10 · openalex created_date 2018/01/26 · openalex publication_date 2018/02/15 · arxiv updated 2018/03/14 · openalex updated_date 2026/08/05
A statistical study of the chromospheric ribbon evolution in H α two-ribbon flares was performed. The data set consists of 50 confined (62%) and eruptive (38%) flares that occurred from June 2000 to June 2015. The flares were selected homogeneously over the H α and Geostationary Operational Environmental Satellite (GOES) classes, with an emphasis on including powerful confined flares and weak eruptive flares. H α filtergrams from the Kanzelhöhe Observatory in combination with Michelson Doppler Imager (MDI) and Helioseismic and Magnetic Imager (HMI) magnetograms were used to derive the ribbon separation, the ribbon-separation velocity, the magnetic-field strength, and the reconnection electric field. We find that eruptive flares reveal statistically larger ribbon separation and higher ribbon-separation velocities than confined flares. In addition, the ribbon separation of eruptive flares correlates with the GOES SXR flux, whereas no clear dependence was found for confined flares. The maximum ribbon-separation velocity is not correlated with the GOES flux, but eruptive flares reveal on average a higher ribbon-separation velocity (by ≈ 10 km s−1). The local reconnection electric field of confined ( cc=0.50 ±0.02 ) and eruptive ( cc=0.77 ±0.03 ) flares correlates with the GOES flux, indicating that more powerful flares involve stronger reconnection electric fields. In addition, eruptive flares with higher electric-field strengths tend to be accompanied by faster coronal mass ejections.