Numerical studies of compact object binaries

紧凑对象二进制的数值研究

• 批准号: RGPIN-2014-03899
• 负责人: Pfeiffer, Harald
• 金额: $ 3.06万
• 依托单位: University of Toronto
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=662060
• 关键词: Numerical; studies; compact; object; binaries

Gravitational waves are ripples in space and time which carry information to us about the most violent events in the universe: Collisions of black holes or neutron stars, supernovae and the big bang itself. During the last decade gravitational wave detectors have been built, most notably the U.S. Advanced Laser Interferometer Gravitational Wave Observatory (LIGO). As early as 2015 these detectors plan to begin searches for gravitational waves. The first GW discovery will be a watershed event, similar to the recent discovery of the Higgs boson. Less dramatic, but arguably even more important will be the subsequent stream of further GW observations, which will yield far-reaching insights into our Universe: Are the observed compact object mergers consistent with general relativity? How do massive stars die, and what compact objects do they leave behind? How does matter behave at supernuclear densities? How do black holes and Neutron stars interact near the centres of galaxies and in globular clusters?**This revolution requires precise knowledge of the expected gravitational waves, which can only be obtained from supercomputer calculations. Knowing the shape of the expected waves allows to find weaker waves, increasing the number of gravitational waves that will be observed. Knowledge of the waveform is also required to determine the precise information about the origin of the wave: for instance, the masses and rotation rates of black holes and neutron stars, their location in the universe.**Prof. Pfeiffer and his research group at CITA are world-leaders in computer simulations of colliding black holes and neutron stars, and in applying their results to gravitational wave astrophysics. With collaborators in the U.S. they have developed an outstanding computer code to simulate colliding compact objects, and have performed the most exhaustive study of colliding black holes. Prof. Pfeiffer's group also participates in the LIGO Scientific Collaboration where it leads the development of low-latency search pipelines that can decide within minutes whether gravitational waves have passed through the telescopes.**This proposal seeks funding to continue this research group to ensure LIGO will discover gravitational waves as quickly as possible, will be as sensitive as possible, and will be able to determine, with minimal bias, the properties of the objects emitting the gravitational waves. This research program spans a gamut of interwoven themes. We propose to continue what we do well: Perform binary black hole calculations and construct waveform templates based on these simulations. Given the accomplishments of Pfeiffer's present Discovery Grant, the complete solution for quasi-circular black hole binaries appears feasible, and is our objective. We propose to expand into a survey of eccentric binary black holes. Such systems -if they exist- must form in profoundly different ways than quasi-circular binaries, and exhibit properties that are absent in quasi-circular binaries. Unfortunately, eccentric binaries are much more difficult to detect. Our simulations will aid in detecting them and -at the least- allow to quantify how sensitive LIGO actually is to such sources. We propose to intensify direct participation in LIGO's search efforts. Finally, we propose to develop a novel, next generation relativistic astrophysics code which removes limiting restrictions of the current code. It will be the foundation for future world-class science from this research group.**The variety of objectives balances immediate needs of LIGO for the first breakthrough discovery with strategic development of long-term scientific leadership. We request funding for about 60% of this research program, with the remainder anticipated from other sources.

引力波是空间和时间中的涟漪，它向我们传递有关宇宙中最剧烈事件的信息：黑洞或中子星的碰撞、超新星和大爆炸本身。在过去的十年中，引力波探测器已经建成，最著名的是美国先进激光干涉仪引力波天文台（LIGO）。早在 2015 年，这些探测器就计划开始搜寻引力波。第一个引力波的发现将是一个分水岭事件，类似于最近发现的希格斯玻色子。不那么引人注目，但可以说更重要的是随后的进一步引力波观测，这将对我们的宇宙产生深远的见解：观察到的致密天体合并是否与广义相对论一致？大质量恒星是如何死亡的，它们会留下什么致密天体？物质在超核密度下如何表现？黑洞和中子星在星系中心附近和球状星团中如何相互作用？**这场革命需要对预期引力波的精确了解，而这只能通过超级计算机计算来获得。了解预期波的形状可以找到较弱的波，从而增加观测到的引力波的数量。还需要了解波形知识才能确定有关波起源的精确信息：例如，黑洞和中子星的质量和旋转速度，以及它们在宇宙中的位置。 **教授。 Pfeiffer 和他在 CITA 的研究小组在黑洞和中子星碰撞的计算机模拟以及将其结果应用于引力波天体物理学方面处于世界领先地位。他们与美国的合作者开发了一种出色的计算机代码来模拟碰撞致密物体，并对碰撞黑洞进行了最详尽的研究。 Pfeiffer 教授的团队还参与了 LIGO 科学合作组织，领导低延迟搜索管道的开发，可以在几分钟内确定引力波是否通过了望远镜。**该提案寻求资金来继续该研究小组，以确保 LIGO将尽快发现引力波，将尽可能敏感，并且能够以最小的偏差确定发射引力波的物体的属性。该研究项目涵盖了一系列相互交织的主题。我们建议继续我们擅长的事情：执行二元黑洞计算并根据这些模拟构建波形模板。鉴于普法伊弗目前的发现补助金所取得的成就，准圆形黑洞双星的完整解决方案似乎是可行的，这也是我们的目标。我们建议扩大对偏心双黑洞的调查。这样的系统——如果存在的话——必须以与准圆形双星截然不同的方式形成，并且表现出准圆形双星所不具备的特性。不幸的是，偏心双星更难被发现。我们的模拟将有助于检测它们，并且至少可以量化 LIGO 对此类源的实际敏感度。我们建议加强对 LIGO 搜索工作的直接参与。最后，我们建议开发一种新颖的下一代相对论天体物理代码，消除当前代码的限制。它将成为该研究小组未来世界级科学的基础。**各种目标平衡了 LIGO 对首次突破性发现的迫切需求与长期科学领导力的战略发展。我们为该研究项目的约 60% 请求资金，其余部分预计从其他来源获得。