The Astrophysical Journal (Jan 2024)
First Comparison of FLARIX Simulations with MSDP Observation of the C1.6 Solar Flare in the Hα Line of Hydrogen
Abstract
The primary objective of this study is to develop a time-dependent model of the flaring atmosphere based on observational data. Here, we present, for the first time, a comparison between numerical simulations of the flaring emission, specifically focusing on the hydrogen H α line, utilizing the FLARIX code and spectral observations of a compact C1.6 GOES-class flare observed on 2012 September 10, by the MSDP imaging spectrograph installed at the Białków Observatory. The Multichannel Subtractive Double Pass imaging spectrograph spectral data, collected with a temporal resolution as fine as 50 ms, enabled a comprehensive analysis of H α line profiles and light curves measured within an area of the flare’s emission. An initial atmospheric model close to VAL-C, with a modified temperature in the upper chromosphere, was employed in simulations. To enhance temporal resolution, modulations of the nonthermal electron (NTE) beam’s parameters were introduced based on variations in observed hard X-ray (HXR) flux (using RHESSI data). The synthesized H α line profiles were compared with the observed spectra. During the impulsive phase of the flare, the evolution of the observed and synthetic H α line intensity agrees, but discrepancies were found in intensities at specific wavelengths of the H α line profile. Fluctuations in the energy flux of NTEs exhibited a strong correlation with the H α emission during the HXR pulse. After considering various effects (such as the filling factor FF = 0.20) that could influence observed emissions, relatively good agreement between theoretical and observed lines was achieved.
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