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

TL;DR

This paper advances solar prominence diagnostics by developing a 2D non-LTE radiative transfer model for He I spectral lines, incorporating atomic fine structure and multi-dimensional effects for realistic intensity profile simulations.

Contribution

It introduces a 2D non-LTE radiative transfer model with atomic fine structure for He I lines, improving the realism of prominence spectral diagnostics.

Findings

Realistic emergent intensity profiles for He I 10830 A and D3 multiplets.

Enhanced modeling accuracy for high-resolution prominence observations.

Initial multi-thread modeling discussions.

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.