Collaborative Research: Predicting the Transient Signals from Galactic Centers: Circumbinary Disks and Tidal Disruptions around Black Holes

合作研究：预测来自银河系中心的瞬态信号：环形盘和黑洞周围的潮汐扰动

• 批准号: 1516125
• 负责人: Manuela Campanelli
• 金额: $ 1.22万
• 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: 2015-08-01 至 2018-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1516125&HistoricalAwards=false
• 关键词: Collaborative; Research; Predicting; Transient; Signals

With masses millions to billions times that of our Sun, the strong gravitational influence of supermassive black holes can heat nearby gas so that it outshines an entire galaxy of stars, and slingshot material outward at relativistic speeds. They exist at the centers of almost every massive galaxy, and they may play a significant role in regulating rates of star formation. Our project aims to produce the most realistic simulations to-date of two of the most dramatic events they can make: the inspiral and merger of two orbiting supermassive black holes and the tidal disruption of stars. Both were once thought to be unobservable, but the advent of very large astronomical surveys sensitive to transients have led to the discovery of numerous tidal disruptions and promise the discovery of many mergers. The prospect of extensive observational data make both very hot topics. The great advantage of this program is the opportunity it provides to integrate many existing research programs into a larger community of scientists, students, and the general public. It will foster crossdisciplinary collaborations among undergraduate students, graduate students, postdoctoral researchers and faculty at the Univ. of Tulsa, Johns Hopkins Univ., NASA/GSFC, and Rochester Institute of Technology. Through such a network, our previous highly successful outreach programs will be able to reach an even larger and more diverse audience. For instance, S. Noble (PI) will continue to speak about hot physics topics with the 100-200 high school students that attend the monthly ?Journal Club? event sponsored by his department, and will work with his collaborators on building similar activities at their institutions.The major goal of this project is to make specific predictions of electromagnetic signatures of circumbinary accretion and tidal disruption events that will allow astronomers to identify, based solely on EM observations, these spectacular events using HST (optical), JWST (IR), Chandra (X-ray), and ISS-Lobster (X-ray), as well as ground based instrumentation such as the Panoramic Survey Telescope and Rapid Response System, which is already in operation, or the planned Large Synoptic Survey Telescope. Such identifications will be a tremendous aid in refining our estimates of the population of merging supermassive black holes, both for estimating the numbers of potential gravitational wave targets and for evaluating the impact of black hole mergers on galaxy evolution. Our simulations on Blue Waters will employ a number of new computational developments needed to achieve the most realistic simulations of these systems to date. They include an adaptive load balancer to evenly distribute runs with nonuniform costs, and a multi-patch system for evolving the magnetohydrodynamics equations on different coordinate domains. It is our intent to make the latter tool publicly available for use in other magnetohydrodynamics codes. Our scientific results will also have a wide-reaching impact on the astrophysical community, both theoretically and observationally. We will release detailed spectra and simulation data for use by observers and future mission development teams. This work comes at a particularly opportune time, as the fields of time-domain and multi-messenger astronomy are growing rapidly.

超大质量黑洞的质量是太阳的数百万至数十亿倍，其强大的引力影响可以加热附近的气体，使其比整个恒星星系更加明亮，并以相对论速度向外弹射物质。它们存在于几乎每个大质量星系的中心，并且可能在调节恒星形成速率方面发挥重要作用。我们的项目旨在对两个最引人注目的事件进行迄今为止最真实的模拟：两个绕轨道运行的超大质量黑洞的吸入和合并以及恒星的潮汐分裂。两者曾经被认为是无法观测到的，但对瞬变敏感的大型天文调查的出现导致了许多潮汐扰动的发现，并有望发现许多合并现象。大量观测数据的前景使这两个话题成为非常热门的话题。该项目的巨大优势是它提供了将许多现有研究项目整合到更大的科学家、学生和公众社区中的机会。它将促进大学本科生、研究生、博士后研究人员和教师之间的跨学科合作。塔尔萨大学、约翰霍普金斯大学、NASA/GSFC 和罗彻斯特理工学院。通过这样的网络，我们之前非常成功的外展计划将能够接触到更多、更多样化的受众。例如，S. Noble (PI) 将继续与参加每月“期刊俱乐部”的 100-200 名高中生谈论热门物理话题。该活动由他的部门赞助，并将与他的合作者合作在他们的机构开展类似的活动。该项目的主要目标是对环双星吸积和潮汐破坏事件的电磁特征做出具体预测，使天文学家能够仅根据在电磁观测中，这些壮观的事件使用 HST（光学）、JWST（IR）、Chandra（X 射线）和 ISS-Lobster（X 射线）以及地面仪器，例如已经投入运行的全景巡天望远镜和快速响应系统，或计划中的大型综合巡天望远镜。这样的识别将极大地帮助我们完善对合并超大质量黑洞数量的估计，既可以估计潜在引力波目标的数量，也可以评估黑洞合并对星系演化的影响。我们对 Blue Waters 的模拟将采用许多新的计算开发技术，以实现迄今为止对这些系统最真实的模拟。它们包括一个自适应负载平衡器，用于以不均匀的成本均匀分配运行，以及一个用于在不同坐标域上演化磁流体动力学方程的多补丁系统。我们的目的是使后一个工具公开可用于其他磁流体动力学代码。我们的科学成果也将对天体物理学界产生广泛的影响，无论是在理论上还是在观测上。我们将发布详细的光谱和模拟数据，供观察员和未来任务开发团队使用。这项工作来得正是时候，因为时域和多信使天文学领域正在迅速发展。