Ein mehrdimensionales implizites numerisches Verfahren zur Modellierung relativistischer und radiativer MHD Strömungen in der Astrophysik

当今各波段观测技术的快速发展需要比以往任何时候都更复杂的数值工具来理解现有的数据。在年轻的恒星物体周围、致密物体周围以及包含黑洞的系统（如微类星体、类星体和伽马射线爆发）中，射流的形成和加速只是尚未解决的问题的一小部分。处理这些天体物理现象需要复杂而强大的求解器，这超出了通常应用于天体物理流体动力学的显式方法的范围。因此，该项目的主要目标是首次开发一个无条件稳定、多维、多阶段的数值求解器，能够为相对论、多组分和辐射MHD流的一组方程提供准平稳解。我们打算应用和修改我们在设计算法IRMHD+时使用的数值方法：一种可用且经过良好测试的隐式，辐射和MHD求解器，它依赖于方程的牛顿公式。它还包括几种重要的辐射、磁和自重力效应，并能够再现磁化流的频谱能量分布。在开发新的狭义相对论求解器（因此命名为SIRMHD+）时，我们打算并行化新的求解器并使其公开可用。

The rapid development of observational technology in all spectral bands nowadays requires more than ever sophisticated numerical tools for understanding the available data. Formation and acceleration of jets around young stellar objects, around compact objects and in systems containing black holes such as in micro-quasars, quasars and in GRBs are only a small sub-set of still unsolved problems. Tackling these astrophysical phenomena requires sophisticated and robust solvers that are beyond the reach of the explicit methods usually applied in astrophysical fluid dynamics. Therefore, the primary goal of this project is to develop for the first time an unconditionally stable, multi-dimensional and multi-stage numerical solver capable of providing quasi-stationary solutions to the set of equations corresponding to relativistic, multi-component, and radiative MHD flows. We intend to apply and modify the numerical approach that we have used in designing the algorithm IRMHD+: an available and well tested implicit, radiative and MHD solver, and which relies on the Newtonian formulation of the equations. It includes also several important radiative, magnetic and self-gravity effects, and is capable of reproducing the spectral energy distributions of magnetized flows. In developing the new special relativistic solver, hence the name SIRMHD+, we intend to parallelize the new solver and make it public-available.