Dormant black holes and neutron stars in stellar binaries

黑洞(BHS)可能是爱因斯坦广义相对论最离奇的预言：在时空区域，引力如此强大，以至于任何东西，即使是光，都无法逃脱。模型预测银河系中存在超过1亿个BHS，但到目前为止只发现了大约20个。这项提议寻求通过使用地面望远镜、来自Gaia航天器的数据和新的数据分析方法来探测BHS，通过它们对围绕它们运行的恒星的引力效应来探测BHS，从而增加这一数字。加州理工学院的一个研究小组将使用该小组开发的各种观察和理论工具进行调查。在此过程中，研究人员还希望发现一个史无前例的中子星样本--中子星是质量较低的BHS的近亲--由像太阳这样的恒星绕轨道运行。最终目标是对银河系的黑洞和中子星数量进行普查，这将最终提高我们对恒星演化、超新星和致密天体形成的物理学的理解。大部分研究将由一名博士生进行，并将构成该学生论文的中心支柱。该小组还将为以轨道动力学为中心的本科生实验室开发开源材料。PI将继续在加州理工大学进行公开演讲，并与未来点燃计划合作，以支持STEM中代表不足的少数族裔(例如，黑人、非裔美国人、美洲原住民和太平洋岛民)的学生。该团队将使用一系列地面和天基设施来发现和表征双星中休眠黑洞(BHS)和中子星(NSS)的统计样本，这些双星有相隔很远的恒星伴星。候选者将从最近发布的第三次盖亚任务数据中挑选出来，该任务为史无前例的350,000个天体测量和光谱双星提供了轨道解决方案。该数据集的样本大小比所有以前的工作增加了50倍，因此为搜索稀有物体提供了新的机会。该小组将使用地面望远镜对最佳候选者进行光谱跟踪。该计划的主要目标是(1)获得GAIA样本中所有~100颗双星的光谱和多历元径向速度，具有BH或NS分量的高概率；(2)测量从1到15个太阳质量的BHS和NSS的质量分布，检测或排除质量差距；(3)限制BHS和NSS的出生踢的频率和大小，使其不受双星偏心和分离的影响；以及(4)检测或排除包含BHS的双星中存在未见的三星。这个项目推进了NSF宇宙大理想之窗的目标。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Black holes (BHs) are perhaps the most bizarre prediction of Einstein's theory of general relativity: regions of spacetime where gravity is so strong that nothing, not even light, can escape. Models predict that more than 100 million BHs exist in the Milky Way, yet only about 20 have been discovered to date. This proposal seeks to increase that number by using telescopes on the ground, data from the Gaia spacecraft, and novel data analysis methods to detect BHs via their gravitation effects on stars that orbit them. A research group at the California Institute of Technology will carry out the investigation using a variety of observational and theoretical tools developed by that group. Along the way, the researchers also expect to discover an unprecedented sample of neutron stars -- close cousins of BHs with lower masses -- orbited by stars like the Sun. The ultimate goal is a census of our Galaxy's BH and neutron star population, which will ultimately improve our understanding of the physics of stellar evolution, supernovae, and compact object formation. A majority of the research will be carried out by a PhD student and will form the central pillar of that student's thesis. The group will also develop open-source material for undergraduate labs centered around orbital dynamics. The PI will continue to give public talks and work with the Future Ignited program at Caltech to support students who are members of under-represented minorities in STEM (for example, Black, African-American, Native American and Pacific Islanders). The team will use a range of ground- and space-based facilities to discover and characterize the first statistical sample of dormant black holes (BHs) and neutron stars (NSs) in binaries with widely separated stellar companions. Candidates will be selected from the recent 3rd data release of the Gaia mission, which provides orbital solutions for an unprecedented 350,000 astrometric and spectroscopic binaries. The dataset represents a factor of 50 increase in sample size over all previous work and thus provides novel opportunities to search for rare objects. The group will use ground-based telescopes to follow-up the best candidates spectroscopically. The main goals of the program are to (1) obtain spectroscopy and multi-epoch radial velocities for all ~100 binaries in the Gaia sample with high probability of having BH or NS components; (2) measure the mass distribution of BHs and NSs from 1 to 15 solar masses, detecting or ruling out the mass gap; (3) constrain the frequency and magnitude of natal kicks for BHs and NSs from binary eccentricities and separations; and (4) detect or rule out the presence of unseen tertiaries within binaries containing BHs. This project advances the goals of the NSF Windows on the Universe Big Idea.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.