solrat 1.1.0

Solar Radiative Transfer non-LTE forward-modeling code.

SolRaT

SolRaT (Solar Radiative Transfer) is a flexible forward modeling code for non-LTE transfer of radiation in stellar atmospheres.

The code provides a three-level framework for modeling radiative transfer:

1. Public API allows to run built-in RT models. Currently, SolRaT ships the non-LTE multi-term atom model (LL04) with multiple constant-slab atmosphere stratification.
2. Modeling API allows to extend existing models or create completely new ones.
3. SolRaT Engine introduces a meta-language that allows the user to write a human-readable code that directly resembles the underlying mathematical equations. The user does not need to focus on code optimization, as it is handled under the hood.

Key Features:

• Physics: Solves non-LTE radiative transfer for multi-term atoms.
• Magnetic Fields: Handles arbitrary magnetic field strengths (Zeeman, Hanle, Paschen-Back effects).
• Atmosphere: Supports multi-slab atmospheres for height stratification under anisotropic illumination (ATL08, HAZEL2).
• Flexibility: Provides a high-level meta-language allowing for writing code that directly resembles the underlying mathematical equations.
• Accessibility: SolRaT is free, open-source, and platform-independent.
• Performance: SolRaT uses high-performance libraries that leverage SIMD instruction sets.
• Extensibility: A clear Modeling API allows for quick prototyping and model adjustments for specific contexts.

How to run:

1. Install SolRaT from PyPi: pip install solrat
2. Explore the demos and tests for usage examples.
3. Explore the documentation.

Citing:

Journal article is pending. In the meantime, if SolRaT has found use in your research, please cite it as

Yakovkin I. I. SolRaT (2023) [computer software]. Retrieved from https://www.yakovkinii.com/solrat/

References:

[LL04] Landi Degl’Innocenti, E., & Landolfi, M. 2004, Polarization in Spectral Lines (Dordrecht: Kluwer)

[ATL08] Asensio Ramos, A., Trujillo Bueno, J., & Landi Degl’Innocenti, E. (2008). Advanced Forward Modeling and Inversion of Stokes Profiles Resulting from the Joint Action of the Hanle and Zeeman Effects. The Astrophysical Journal, 683(1), 542–565.

[HAZEL2] Link

Keywords:

Non-LTE, Stokes Profiles, Inversion, Synthesis, Paschen-Back, Hanle, Zeeman, Magnetic Fields, Sun, Solar Atmosphere, Radiative Transfer, Polarization, Spectral Lines, Two-Term Atom Model

Copyright (2023) Ivan I. Yakovkin