Numerical Simulations of Compact Neutron Star Binary Mergers

该奖项资助对双中子星合并以及由一颗中子星和一个黑洞组成的双星的研究。这些现象是地面探测器（如激光干涉仪引力波天文台（LIGO））重力辐射的主要来源之一，它们可能解释了观测到的短时间伽马射线暴（GRBs）。计算机模型既需要计算这些合并的预期重力波形，也需要测试它们作为grb来源的可行性。该项目将对黑洞-中子星和中子星-中子星合并进行大规模、详细的计算机模拟，重点关注三个主要问题。首先，它将研究合并后黑洞周围遗留的核物质碎片的演变，特别是磁场和中微子辐射的影响，这些影响预计将对向GRB提供能量至关重要。其次，它将通过模拟目前尚未研究的黑洞质量和自旋的极端情况来探索黑洞-中子星双星的多样性。第三，描述中子星物理对引力波的影响。准确的重力波形预测对于探测LIGO数据中的双并合信号以及提取中子星结构信息至关重要。这样的信息可能会限制核物质的未知性质。为此项目开发的数值技术将适用于天体物理流体动力学中的其他问题。该奖项的大部分资金用于学生支持。PI指导研究生和本科生。这些学生在计算机编程、数值问题解决和流体力学方面接受了宝贵的培训，获得了适用于广泛技术领域的重要技能。这个项目的结果将用于向更广泛的公众传播天体物理学的兴奋。

This award funds research into mergers of binary neutron stars and of binaries consisting of a neutron star and a black hole. These phenomena are among the primary sources of gravitational radiation for ground-based detectors such as the Laser Interferometer Gravitational Wave Observatory (LIGO), and they may explain the observed short-duration gamma ray bursts (GRBs). Computer models are needed both to calculate the expected gravitational waveforms for these mergers and also to test their viability as sources of GRBs. This project will carry out large-scale, detailed computer simulations of black hole-neutron star and neutron star-neutron star mergers, focusing on three main issues. First, it will study the evolution of the nuclear matter debris left around the post-merger black hole, especially the effects of magnetic fields and neutrino radiation that are expected to be critical in delivering energy to a GRB. Second, it will explore the variety of black hole-neutron star binaries by modeling currently unstudied extremes of black hole mass and spin. Third, it will characterize the effects of neutron star physics on the gravitational waveforms.Accurate gravitational waveform predictions will be crucial for detecting binary merger signals in LIGO data and for extracting information about the neutron star structure. Such information might be able to constrain unknown properties of nuclear matter. Numerical techniques developed for this project will be applicable to other problems in astrophysical fluid dynamics. Most of the funding from this award is used for student support. The PI directs both graduate and undergraduate students. These students receive valuable training in computer programming, numerical problem solving, and hydrodynamics, gaining important skills applicable to a broad range of technical fields. Results from this project will be used in communicating the excitement of astrophysics to the wider public.