Formal Solutions for Polarized Radiative Transfer. III. Stiffness and Instability
Additional information
Authors
Janett G.,
Paganini A.
Type
Journal Article
Year
2018
Language
English
Abstract
Efficient numerical approximation of the polarized radiative transfer equation is challenging because this system of ordinary differential equations exhibits stiff behavior, which potentially results in numerical instability. This negatively impacts the accuracy of formal solvers, and small step-sizes are often necessary to retrieve physical solutions. This work presents stability analyses of formal solvers for the radiative transfer equation of polarized light, identifies instability issues, and suggests practical remedies. In particular, the assumptions and the limitations of the stability analysis of Runge–Kutta methods play a crucial role. On this basis, a suitable and pragmatic formal solver is outlined and tested. An insightful comparison to the scalar radiative transfer equation is also presented.
Journal
Astrophysical Journal
Volume
857
Start page number
91
Keywords
irsol-refereed-scientific-papers
