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The strong enhancement of the ultraviolet emission during solar flares is usually taken as an indication of plasma heating in the lower solar atmosphere caused by the deposition of the energy released during these events. Images taken with broadband ultraviolet filters by the {em Transition Region and Coronal Explorer} (TRACE) and {em Atmospheric Imaging Assembly} (AIA 1600 and 1700~AA) have revealed the morphology and evolution of flare ribbons in great detail. However, the spectral content of these images is still largely unknown. Without the knowledge of the spectral contribution to these UV filters, the use of these rich imaging datasets is severely limited. Aiming to solve this issue, we estimate the spectral contributions of the AIA UV flare and plage images using high-resolution spectra in the range 1300 to 1900~AA from the Skylab NRL SO82B spectrograph. We find that the flare excess emission in AIA 1600~AA is { dominated by} the ion{C}{4} 1550~AA doublet (26%), ion{Si}{1} continua (20%), with smaller contributions from many other chromospheric lines such as ion{C}{1} 1561 and 1656~AA multiplets, ion{He}{2} 1640~AA, ion{Si}{2} 1526 and 1533~AA. For the AIA 1700~AA band, ion{C}{1} 1656~AA multiplet is the main contributor (38%), followed by ion{He}{2} 1640 (17%), and accompanied by a multitude of other, { weaker} chromospheric lines, with minimal contribution from the continuum. Our results can be generalized to state that the AIA UV flare excess emission is of chromospheric origin, while plage emission is dominated by photospheric continuum emission in both channels.
Context. Theoretical calculations have shown that when solar prominences move away from the surface of the Sun, their radiative output is affected via the Doppler dimming or brightening effects. Aims. In this paper we ask whether observational signat
Waves have long been thought to contribute to the heating of the solar corona and the generation of the solar wind. Recent observations have demonstrated evidence of quasi-periodic longitudinal disturbances and ubiquitous transverse wave propagation
We report an observation of a partially erupting prominence and associated dynamical plasma processes based on observations recorded by the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory (SDO). The prominence first goes th
We present an analysis of off-limb cool flare loops observed by SDO/AIA during the gradual phase of SOL2017-09-10T16:06 X8.2-class flare. In the EUV channels starting from the 335 {AA} one, cool loops appear as dark structures against the bright loop
We found systematic microwave source motions along a flare-arcade using Nobeyama Radioheliograph (NoRH) 17 GHz images. The motions were associated with a X-class disk flare which occurred on 15th February 2011. For this study, we also used EUV images