ASTRODEBATA / Pavol Schwartz: Modelling of solar filaments and prominences with non-LTE radiative transfer in 1D and 2D
Modelling of solar filaments and prominences with non-LTE radiative transfer in 1D and 2D
(Astronomical Institute of Slovak Academy of Sciences Tatranska, Lomnica, Slovak Republic)
I present a review of modelling of solar prominences and filaments observed spectroscopically in the Lyman line series of hydrogen and in Hα using detailed non-LTE radiative transfer from the year 2006 up. The so-called ’forward modelling’ was used, it means that extended catalogues of synthetic profiles were calculated and the best model was searched by chi-square minimization between synthetic and observed spectral line profiles.
The modelling was made for diagnostics of hydrogen plasma of both quiescent and active prominences/filaments to understand better their nature and also physical processes leading to their possible activation. Prominence/filament was approximated by a geometrically simple slab. A possibility of increase of temperature towards the slab edges – so called prominence-corona transition regions – were also introduced into the modelling, because their occurrence in peripheral parts of filaments/prominences is evident from observations.
We started with the modelling in 1D geometry, but in 2010 we realized a necessity of 2D geometry, because profiles from peripheral parts of filaments/prominences could not be fitted reliably when the slab in the 1D geometry is irradiated from the solar surface only at its bottom. On the other hand, 2D slab is irradiated both from its bottom and sides. Later, magnetohydrostatic equilibrium and fine structure (multi-slabs) was applied.
Now, we are addopting the 2D-slab codes also for modelling of eruptive prominences and we are calculating grids of models containing synthetic Lyman α intensities which will be later compared with observations in the Lyman α channel made by the METIS coronograph on board of the Solar Orbiter satellite.