Unfolding the Dynamic and Colorful Lives of Compact Object Mergers

展现紧凑对象合并的动态和多彩生活

• 批准号: 1814782
• 负责人: Wen-fai Fong
• 金额: $ 44.91万
• 依托单位: Northwestern University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2022-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1814782&HistoricalAwards=false
• 关键词: Unfolding; Dynamic; Colorful; Lives; Compact

The mergers of two astronomical compact objects (neutron stars and/or black holes) in a binary system serve as sources of gravitational wave emission, potential sites of heavy element nucleosynthesis, and laboratories for high-energy astrophysical processes not seen elsewhere in the universe. With the onset of advanced gravitational wave detectors, only recently have astronomers begun to place direct constraints on these processes. Short gamma-ray bursts (SGRBs), which are detected at cosmological distances, also offer a unique and independent window into the dynamic and colorful lives of compact object mergers. A research group at Northwestern University, under the direction of the principal investigator (PI), will capitalize on complementary streams of data from gravitational wave observatories, ground-based telescopes and space-based gamma-ray and X-ray missions to: (i) develop informed follow-up strategies for electromagnetic (EM) observations following gravitational wave events, (ii) confront theoretical models of heavy element production in mergers with optical and near-infrared observations, (iii) place constraints on the fraction of mergers that produce SGRBs with radio through X-ray observations, and (iv) decipher the histories of the pre-merger binary systems with a complete census of their host galaxies. To make this research publicly accessible in a novel way, the PI will partner with Evanston (Illinois) Township High School (ETHS) which has an on-campus planetarium. The PI will use the planetarium as a venue for engaging students with research material and exposing students to Astronomy researchers from diverse backgrounds.The research group will utilize the inferred properties of previous SGRBs to build light curve prediction tools that will optimize an observatory's chance of an EM counterpart detection following a gravitational wave event. These adaptable tools will serve as an important community resource, not only for determining current observing strategies but also for planning future EM surveys. The research group will also place direct, observational constraints on the role of mergers in populating the Universe with heavy elements, by determining independently-measured ejecta masses and event rates. The researchers will build a complete census of SGRB host galaxies and the spatial offsets of bursts from the galaxy centers. From these observations, the researchers will determine the distributions of merger kick velocities and delay times. These distributions are vital inputs for binary evolution models, yet they are highly uncertain. The project is well-designed to exploit both methods of merger discovery: gravitational wave emission from Advanced LIGO/Virgo and gamma-ray burst detection from space-based missions. For all objectives in this proposal, the research group will make crucial connections between the local population of compact object mergers discovered by Advanced LIGO/Virgo and their cosmological analogues.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

双星系统中两个致密天体（中子星和/或黑洞）的合并是引力波发射源，重元素核合成的潜在场所，以及宇宙中其他地方看不到的高能天体物理过程的实验室。随着先进的引力波探测器的出现，直到最近天文学家才开始对这些过程进行直接限制。在宇宙学距离上探测到的短伽马射线暴（SGRB）也为紧凑物体合并的动态和丰富多彩的生活提供了一个独特而独立的窗口。西北大学的一个研究小组在首席研究员（PI）的指导下，将利用来自引力波观测站，地面望远镜和天基伽马射线和X射线任务的补充数据流：（i）在引力波事件发生后，为电磁观测制定知情的后续战略，（ii）用光学和近红外观测来对抗合并中重元素产生的理论模型，（iii）通过X射线观测来限制产生SGRB的合并比例，和（iv）破译合并前的双星系统的历史与其宿主星系的完整普查。 为了使这项研究以一种新颖的方式公开，PI将与埃文斯顿（伊利诺伊州）乡镇高中（ETHS）合作，该高中拥有校园天文馆。PI将利用天文馆作为一个场地，让学生参与研究材料，并让学生接触来自不同背景的天文学研究人员。研究小组将利用先前SGRB的推断性质来构建光变曲线预测工具，以优化天文台在引力波事件后发现EM对应物的机会。这些适应性强的工具将成为重要的社区资源，不仅用于确定当前的观测策略，还用于规划未来的EM调查。研究小组还将通过确定独立测量的喷出物质量和事件率，对合并在重元素填充宇宙中的作用进行直接的观测限制。 研究人员将建立一个完整的SGRB宿主星系的普查和星系中心爆发的空间偏移。 根据这些观测结果，研究人员将确定合并反冲速度和延迟时间的分布。这些分布是二元演化模型的重要输入，但它们具有高度的不确定性。该项目旨在利用两种合并发现方法：Advanced LIGO/Virgo的引力波发射和天基任务的伽马射线爆发探测。 对于该提案中的所有目标，研究小组将在Advanced LIGO/Virgo发现的紧凑天体合并的当地人口与其宇宙学类似物之间建立关键联系。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Probing Kilonova Ejecta Properties Using a Catalog of Short Gamma-Ray Burst Observations

• DOI: 10.3847/1538-4357/ac04b4
• 发表时间: 2021-01
• 期刊: The Astrophysical Journal
• 作者: J. Rastinejad;W. Fong;C. Kilpatrick;K. Paterson;N. Tanvir;A. Levan;B. Metzger;E. Berger;R. Chornock;B. Cobb;T. Laskar;P. Milne;A. Nugent;N. Smith

Short GRB Host Galaxies. II. A Legacy Sample of Redshifts, Stellar Population Properties, and Implications for Their Neutron Star Merger Origins

• DOI: 10.3847/1538-4357/ac91d1
• 发表时间: 2022-06
• 期刊: The Astrophysical Journal
• 作者: A. Nugent;W. Fong;Y. Dong 董;J. Leja;E. Berger;M. Zevin;R. Chornock;B. Cobb;L. Kelley;C. Kilpatrick;A. Levan;R. Margutti;K. Paterson;D. Perley;A. R. Escorial;N. Smith;N. Tanvir

A kilonova following a long-duration gamma-ray burst at 350 Mpc

• DOI: 10.1038/s41586-022-05390-w
• 发表时间: 2022-04
• 期刊: Nature
• 影响因子: 64.8
• 作者: J. Rastinejad;B. Gompertz;A. Levan;W. Fong;M. Nicholl;G. Lamb;D. Malesani;A. Nugent;S. Oates;N. Tanvir;A. de Ugarte Postigo;C. Kilpatrick;C. Moore;B. Metzger;M. Ravasio;A. Rossi;G. Schroeder;J. Jencson;D. Sand;N. Smith;José Feliciano Agüí Fernández;E. Berger;P. Blanchard;R. Chornock;B. Cobb;M. De Pasquale;J. Fynbo;L. Izzo;D. A. Kann;T. Laskar;E. Marini;K. Paterson;A. R. Escorial;H. Sears;C. Thöne

On the Rate of Neutron Star Binary Mergers from Globular Clusters

• DOI: 10.3847/2041-8213/ab5dc5
• 发表时间: 2019-10
• 期刊: The Astrophysical Journal Letters
• 作者: Claire S. Ye;W. Fong;K. Kremer;C. Rodriguez;S. Chatterjee;G. Fragione;F. Rasio

Forward Modeling of Double Neutron Stars: Insights from Highly Offset Short Gamma-Ray Bursts

• DOI: 10.3847/1538-4357/abc266
• 发表时间: 2019-10
• 期刊: The Astrophysical Journal
• 作者: M. Zevin;L. Kelley;A. Nugent;W. Fong;C. Berry;V. Kalogera