Collaborative Research: Simulation Neutron Star-Black Hole Inspirals. From Binaries to Accretion and Jets

吸积黑洞双星系统（ABHB）是由一颗围绕一个小黑洞运行的星星组成。一个特别有趣的例子是中子星-黑洞（NS-BH）双星，它可能是引力波观测站（如Advanced LIGO）的引力波源。来自NS-BH双星的引力和电磁波信号包含了关于双星特定演化的信息，包括磁效应和中子星星被黑洞潮汐力破坏的信息。该奖项支持发展研究ABHB和相关系统的计算基础设施和技术。这包括进一步开发HAD，这是一个免费提供的模块化计算工具包，用于在分布式并行环境中求解微分方程。HAD提供复杂的自适应网格细化功能，允许用户联合收割机组合不同类型的微分方程和/或数值方法。为了满足模拟ABHB系统和提取有价值的物理信息的需要，将进一步发展和实现求解爱因斯坦方程和磁流体动力学（MHD）方程的技术，这项工作有助于推进重要科学问题的数值技术，以及创建和传播先进的分布式计算工具。基础设施的模块化设计允许其他研究人员共享和扩展这些工具。最后，本研究涉及博士后研究人员，研究生和本科生的培训。

An accreting black hole binary system (ABHB) consists of a star orbiting a small black hole. One particularly interesting example is a neutron star-black hole (NS-BH) binary, which may be interesting sources of gravitational waves for gravitational wave observatories such as Advanced LIGO. The gravitational and electromagnetic wave signals from NS-BH binaries contains information about the particular evolution of the binary, including magnetic effects and the disruption of the neutron star by the tidal forces of the black hole.This award supports the development of computational infrastructure and techniques to study ABHBs and related systems. This includes the further development of HAD, a freely available, modular computational toolkit for solving differential equations in a distributed parallel environment. HAD provides sophisticated adaptive mesh refinement capabilities, which allow the user to combine different types of differential equations and/or numerical methods. Techniques for solving the Einstein equations and magnetohydrodynamics (MHD) equations will be further developed and implemented in the code to meet the demands of simulating ABHB systems and extracting valuable physical information.This work serves to advance numerical techniques for an important scientific problem, as well as the creation and dissemination of advanced tools for distributed computing. The modular design of the infrastructure allows other researchers to share and extend these tools. Finally, this study involves the training of postdoctoral researchers, graduate students, and undergraduates.