General-relativistic radiation transport scheme in $\texttt{Gmunu}$ I: Implementation of two-moment based multi-frequency radiative transfer and code tests
Abstract
We present the implementation of two-moment based general-relativistic multi-group radiation transport module in the eneral-relativistic ltigrid merical () code. On top of solving the general-relativistic magnetohydrodynamics and the Einstein equations with conformally flat approximations, the code solves the evolution equations of the zeroth- and first-order moments of the radiations. Analytic closure relation is used to obtain the higher order moments and close the system. The finite-volume discretisation has been adopted for the radiation moments. The advection in spatial and frequency spaces are handled explicitly. In addition, the radiation-matter interaction terms, which are very stiff in the optically thick region, are solved implicitly. Implicit-explicit Runge-Kutta schemes are adopted for time integration. We test the implementation with a number of numerical benchmarks from frequency-integrated to frequency dependent cases. Furthermore, we also illustrate the astrophysical applications in hot neutron star and core-collapse supernovae modellings, and compare with other neutrino transport codes.
Keywords
Cite
@article{arxiv.2303.03261,
title = {General-relativistic radiation transport scheme in $\texttt{Gmunu}$ I: Implementation of two-moment based multi-frequency radiative transfer and code tests},
author = {Patrick Chi-Kit Cheong and Harry Ho-Yin Ng and Alan Tsz-Lok Lam and Tjonnie Guang Feng Li},
journal= {arXiv preprint arXiv:2303.03261},
year = {2023}
}