Collaborative Research: Accretion Dynamics of Black Hole Mergers

合作研究：黑洞合并的吸积动力学

• 批准号: 1516150
• 负责人: Manuela Campanelli
• 金额: $ 33.73万
• 依托单位: Rochester Institute of Tech
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-01 至 2019-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1516150&HistoricalAwards=false
• 关键词: Collaborative; Research; Accretion; Dynamics; Black

It is estimated that somewhere in the universe a few pairs of supermassive black holes merge every single year, leaving behind a still more massive single black hole at the centers of the galaxies where this occurs. The energy released is enormous, and the effect on galactic evolution profound, but no such event has ever been identified because the overwhelming majority of the energy is released in gravitational waves, which are as yet undetectable. This project will characterize the visible light signals that should be given off by nearby gas under the influence of the event, using complex numerical simulations. Training in these techniques will be of great value for the future activities of the junior researchers on the team.Although there should be sufficient gas close enough to the merger events to give off visible radiation, the character of any emitted signals is unknown. Particular questions include in which band most of the light will emerge, what is its spectrum, and how does the radiated power vary in time? This work will start to answer these questions. The extremely complex interaction between the surrounding gas and a pair of black holes bound to one another involves strongly nonlinear physics, including magnetohydrodynamic (MHD) turbulence, shocks, and dynamical spacetimes, which can only be tackled numerically. This requires carefully structured simulations using radiation transfer post-processing to predict key observable features, using the team's new infrastructure that supports consistent MHD calculations on separate grids and across qualitatively different spacetimes. Calculations with astrophysically plausible parameters should identify unique photon signals for observers to locate black holes on their way to merger.This computational system should also be useful to many other astrophysical simulations. The work will train a number of graduate students and post-doctoral fellows in the techniques of large-scale numerical simulation, skills that are valuable far beyond the confines of astrophysical research. The team is active in outreach both to non-science students and to the general public, including work to engage deaf and hard-of-hearing students in the sciences.

据估计，宇宙中的某个地方每年都会合并几双超大型黑洞，在发生这种情况的星系中心留下一个更大的单个黑洞。 释放的能量是巨大的，对银河进化的影响深远，但是从未发现过这种事件，因为绝大多数能量在重力波中释放，尚未发现。 该项目将使用复杂的数值模拟在事件影响下应在事件影响下应在附近气体散发出的可见光信号。 这些技术的培训对于团队中的初级研究人员的未来活动将具有很大的价值。尽管应该有足够的气体与合并事件足够接近以散发可见的辐射，但任何发射信号的特征都是未知的。 特定的问题包括大部分光线将出现在哪个频段中，其频谱是什么？辐射功率在时间上有何不同？这项工作将开始回答这些问题。 周围气体和一对黑洞之间的极其复杂的相互作用彼此绑定，涉及强烈的非线性物理，包括磁性水力学（MHD）湍流，冲击和动态空位，只能在数值上处理。 这需要使用辐射转移后处理进行仔细的结构化模拟，以预测团队的新基础架构，该新基础架构支持在单独的网格上以及在定性不同的空间上支持一致的MHD计算。 用天体物理上合理的参数计算应确定独特的光子信号，以便观察者在合并的途中定位黑洞。该计算系统也应对许多其他天体物理模拟有用。 这项工作将培训许多研究生和博士后研究员的大规模数值模拟技术，这些技能远远超出了天体物理研究的范围。 该团队活跃于非科学专业的学生和公众，包括吸引聋哑学生和听力障碍学生的努力。

项目成果

Circumbinary Disk Accretion into Spinning Black Hole Binaries

• DOI: 10.3847/1538-4357/abf0af
• 发表时间: 2021-01
• 期刊: The Astrophysical Journal
• 作者: F. L. Lopez Armengol;L. Combi;M. Campanelli;S. Noble;J. Krolik;Dennis B. Bowen;M. Avara;V. Mewes;H. Nakano