Flare Expansion to a Magnetic Rope Accompanied by Rare Radio Bursts

0537303 - ASÚ 2021 RIV US eng J - Článek v odborném periodiku
Zemanová, Alena - Karlický, Marian - Kašparová, Jana - Dudík, Jaroslav
Flare Expansion to a Magnetic Rope Accompanied by Rare Radio Bursts.
Astrophysical Journal. Roč. 905, č. 2 (2020), č. článku 111. ISSN 0004-637X. E-ISSN 1538-4357
Grant CEP: GA ČR(CZ) GA18-09072S; GA ČR(CZ) GA19-09489S; GA ČR GA20-07908S; GA ČR(CZ) GC20-09922J
Institucionální podpora: RVO:67985815
Klíčová slova: solar-flares * model * reconnection
Obor OECD: Astronomy (including astrophysics,space science)
Impakt faktor: 5.877, rok: 2020
Způsob publikování: Omezený přístup
https://doi.org/10.3847/1538-4357/abc424

We present multispectral analysis (radio, H alpha, ultraviolet (UV)/extreme ultraviolet (EUV), and hard X-ray) of a confined flare from 2015 March 12. This flare started within the active region NOAA 12 297 and then it expanded into a large preexisting magnetic rope embedded with a cold filament. The expansion started with several brightenings located along the rope. This process was accompanied by a group of slowly positively drifting bursts in the 0.8-2 GHz range. The frequency drift of these bursts was 45-100 MHz s(-1). One of the bursts had an S-like form. During the brightening of the rope we observed a unique bright EUV structure transverse to the rope axis. The structure was observed in a broad range of temperatures and it moved along the rope with the velocity of about 240 km s(-1). When the structure dissipated, we saw a plasma further following twisted threads in the rope. The observed slowly positively drifting bursts were interpreted considering particle beams and we show that one with the S-like form could be explained by the beam propagating through the helical structure of the magnetic rope. The bright structure transverse to the rope axis was interpreted considering line-of-sight effects and the dissipation-spreading process, which we found to be more likely.
Trvalý link: http://hdl.handle.net/11104/0315031