Kozai-Lidov Oscillations in Triple and Quadruple Systems of Stars and Their Compact Objects

恒星及其致密天体三重和四重系统中的科扎伊-利多夫振荡

• 批准号: 1313252
• 负责人: Todd Thompson
• 金额: $ 27.2万
• 依托单位: Ohio State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-01 至 2019-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1313252&HistoricalAwards=false
• 关键词: Kozai; Lidov; Oscillations; Triple; Quadruple

Close stellar and compact object binaries are important to an extremely broad variety of astrophysical phenomena. Yet, most close binaries are not binaries. They are triple systems. Moreover, triple and quadruple systems are common on aggregate, representing roughly 10% and 3% of stellar systems on the sky, respectively. Most importantly, the long-term dynamics of multiple systems is not understood and fully characterized. Very recent advances in our understanding of the Kozai-Lidov resonance (and its extensions) have the chance to dramatically reconfigure our understanding of the production of close compact object and stellar binaries of all types. The investigators are at the forefront of these developments. They suggested that triple systems could produce "prompt" mergers of WD-WD binaries, perhaps leading to the Type Ia supernovae that are observed to immediately follow episodes of star formation. They also showed that mass loss in binaries could instigate the "Eccentric Kozai Mechanism," (EKM) producing close WD and NS-stellar binaries. Finally, and speculatively, they also suggested a triple or quadruple origin for Tycho B, an exceedingly rare low-metallicity A-star at the center of Tycho's supernova remnant that may be a blue straggler.The investigators propose a broad suite of projects aimed at understanding the demographics, evolution, dynamics, and implications of triple and quadruple systems composed of stars and their compact objects. They will do both broad sweeps through parameter space, and focused studies of individual systems. Among the projects they will pursue, they will (1) map the space of the EKM and the Mass-Loss Induced EKM for the first time, (2) calculate the gravitational wave background and foregrounds from eccentric compact object binaries in triple systems, (3) explore the origin of the enigmatic ms-pulsar PSR J1903+0327, (4) attempt to understand the period commensurability observed in the recently discovered doubly-eclipsing quadruple A-star systemCzeV343, (5) develop evolutionary scenarios for Tycho B and explore the implications for otherIa remnants, (6) expand the secular dynamics of 3-body systems to higher order, (7) compute the delay-time distribution of Ia supernovae formed from white dwarf-white dwarf mergers in coeval and dynamically formed triple systems, (8) attempt to understand the evolution of massive star triple systems with explosive mass loss and neutron star kicks, and (9) understand if direct compact object collisions can be driven by Kozai-Lidov oscillations.A significant part of the work will be carried out by graduate and undergraduate students, providing extensive training in cutting-edge scientific research. Results from this research will be broadly disseminated by publication in peer-reviewed journals, conference proceedings, and by the press. In addition, the investigators propose an interesting education and outreach component that targets the public broadly, called "Ask An Astrophysicist!"

紧密的恒星和紧密的天体双星对各种各样的天体物理现象都很重要。然而，大多数接近的二进制文件并不是二进制文件。它们是三重系统。此外，三重和四重星系总体上很常见，分别约占天空中恒星系统的10%和3%。最重要的是，多个系统的长期动力学还没有被理解和充分表征。最近我们对Kozai-Lidov共振（及其扩展）的理解取得了进展，这有机会极大地重新配置我们对所有类型的紧密天体和双星产生的理解。调查人员处于这些发展的前沿。他们认为，三重系统可能会产生WD-WD双星的“迅速”合并，也许会导致Ia型超新星，这种超新星会在恒星形成后立即被观察到。他们还表明，双星的质量损失可能会引发“偏心的Kozai机制”（EKM），产生紧密的WD和ns双星。最后，他们还推测，第谷B有三颗或四颗起源。第谷B是一颗极其罕见的低金属丰度a星，位于第谷超新星遗迹的中心，可能是一颗蓝离散星。研究人员提出了一套广泛的项目，旨在了解由恒星及其致密天体组成的三重和四重系统的人口统计、演化、动力学和含义。他们将对参数空间进行广泛的扫描，并对单个系统进行集中研究。在他们将要进行的项目中，他们将(1)首次绘制EKM和质量损失诱导的EKM的空间图，(2)计算三重系统中偏心致密天体双星的引力波背景和前景，(3)探索神秘的ms-脉冲星PSR J1903+0327的起源，(4)尝试理解在最近发现的双蚀四a星系统czev343中观测到的周期可通约性。(5)发展第谷B的演化场景并探索其他Ia残余物的影响；(6)将三体系统的长期动力学扩展到更高阶；(7)计算由白矮星-白矮星合并形成的Ia超新星在同时期和动态形成的三重系统中的延迟时间分布；(8)试图理解具有爆炸质量损失和中子星弹射的大质量恒星三重系统的演化。(9)了解Kozai-Lidov振荡是否可以驱动直接致密物体碰撞。大部分工作将由研究生和本科生进行，为前沿科学研究提供广泛的培训。这项研究的结果将通过同行评议的期刊、会议记录和新闻界的出版物广泛传播。此外，研究人员还提出了一个针对公众的有趣的教育和推广组成部分，名为“问天体物理学家！”