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arXiv · 0811.4753

2D non-LTE radiative modelling of He I spectral lines formed in solar prominences

L. Leger·F. Paletou
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Abstract

The diagnosis of new high-resolution spectropolarimetric observations of solar prominences made in the visible and near-infrared mainly, requires a radiative modelling taking into account for both multi-dimensional geometry and complex atomic models. Hereafter we contribute to the improvement of the diagnosis based on the observation of He I multiplets, by considering 2D non-LTE unpolarized radiation transfer, and taking also into account the atomic fine structure of helium. It is an improvement and a direct application of the multi-grid Gauss-Seidel/SOR iterative scheme in 2D cartesian geometry developed by us. It allows us to compute realistic emergent intensity profiles for the He I 10830 A and D3 multiplets, which can be directly compared to the simultaneous and high-resolution observations made at THeMIS. A preliminary 2D multi-thread modelling is also discussed.

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L. Leger, F. Paletou. 2008-11-28. 2D non-LTE radiative modelling of He I spectral lines formed in solar prominences. https://doi.org/10.1051/0004-6361%2F200810296

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