Fast 2D non-LTE radiative modelling of prominences I. Numerical methods and benchmark results

Abstract

New high-resolution spectropolarimetric observations of solar prominences require improved radiative modelling capabilities in order to take into account both multi-dimensional - at least 2D - geometry and complex atomic models. This makes necessary the use of very fast numerical schemes for the resolution of 2D non-LTE radiative transfer problems considering freestanding and illuminated slabs. The implementation of Gauss-Seidel and successive over-relaxation iterative schemes in 2D, together with a multi-grid algorithm, is thoroughly described in the frame of the short characteristics method for the computation of the formal solution of the radiative transfer equation in cartesian geometry. We propose a new test for multidimensional radiative transfer codes and we also provide original benchmark results for simple 2D multilevel atom cases which should be helpful for the further development of such radiative transfer codes, in general.

arXiv comment10 pages, 8 figures, accepted to A&A

References in corpus (4)

• On the accuracy of the ALI method for solving the radiative transfer equation
• Fast multilevel radiative transfer
• Exact solution of the standard transfer problem in a stellar atmosphere
• Multi-Resolution Radiative Transfer for Line Emission

Cited by in corpus (6)

• Solving radiative transfer with line overlaps using Gauss Seidel algorithms
• 1.5D NLTE spectral synthesis of a 3D filament/prominence simulation
• Numerical non-LTE 3D radiative transfer using a multigrid method
• 2D non-LTE radiative modelling of He I spectral lines formed in solar prominences
• A conjugate gradient method for the solution of the non-LTE line radiation transfer problem
• Accelerating NLTE radiative transfer by means of the Forth-and-Back Implicit Lambda Iteration: A two-level atom line formation in 2D Cartesian coordinates