Signatures of Helium Continuum in Cool Flare Loops Observed by SDO/AIA

0535752 - ASÚ 2021 RIV US eng J - Článek v odborném periodiku
Heinzel, Petr - Schwartz, P. - Lörinčík, Juraj - Koza, J. - Jejčič, S. - Kuridze, D.
Signatures of Helium Continuum in Cool Flare Loops Observed by SDO/AIA.
Astrophysical Journal Letters. Roč. 896, č. 2 (2020), č. článku L35. ISSN 2041-8205. E-ISSN 2041-8213
Grant CEP: GA ČR(CZ) GA19-17102S
Institucionální podpora: RVO:67985815
Klíčová slova: solar flares * solar coronal loops * solar extreme ultraviolet emission
Obor OECD: Astronomy (including astrophysics,space science)
Impakt faktor: 7.413, rok: 2020
Způsob publikování: Omezený přístup
https://doi.org/10.3847/2041-8213/ab9839

We present an analysis of off-limb cool flare loops observed by the Solar Dynamics Observatory (SDO)/Atmospheric Imaging Assembly (AIA) during the gradual phase of SOL2017-09-10T16:06 X8.2-class flare. In the extreme-ultraviolet (EUV) channels starting from the 335 A one, cool loops appear as dark structures against the bright loop arcade. These dark structures were precisely coaligned (spatially and temporally) with loops observed by Swedish Solar Telescope (SST) in emission lines of hydrogen and ionized calcium. A recently published semi-empirical model of cool loops based on SST observations serves to predict the level of hydrogen and helium recombination continua. The continua were synthesized using an approximate non-LTE (i.e., departures from local thermodynamic equilibrium) approach and theoretical spectra were then transformed to AIA signals.
Trvalý link: http://hdl.handle.net/11104/0313693