The Galactic Center Orbits Initiative: Probing the Physics & Astrophysics of the Closest Supermassive Black Hole

银河中心轨道计划：探索物理学

• 批准号: 1909554
• 负责人: Andrea Ghez
• 金额: $ 82.02万
• 依托单位: University of California-Los Angeles
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2023-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1909554&HistoricalAwards=false
• 关键词: Galactic; Center; Orbits; Initiative; Probing

Our Milky Way galaxy has a supermassive black hole (SMBH) at its center. The investigators have observed individual stars orbiting the SMBH for many years. The investigators use these observations study the effects of strong gravity and the dense environment on these stars. Their observations show the stars moving very fast around the SMBH, as expected. The investigators find the environment near the SMBH is the most extreme of the natural world that can be studied by observations from Earth. These observations, combined with models, are used as a laboratory for understanding the physical principles that govern our universe. The investigators plan further observations using the world's largest telescopes to search for new properties of gravity that can only be detected in extreme environments. Using precise measurements of the stars' motions, the investigators have determined the size and the distance of the SMBH. So far, their observations are exactly consistent with predictions of Einstein's general theory of relativity. The aim of their new project is to refine their tests of relativity by continued monitoring of the motions of stars around the SMBH. They carefully measure how much the stars' positions will stray from the classical description of their orbits. They will more precisely measure the distance to the Galactic center, which sets the size scale of the Galaxy. Furthermore, they expect the densely packed stars at the Galactic center to become joined as binary stars that could ultimately merge with each other to produce new kinds of stars. Some can ultimately become star-sized black holes. The investigators convey to the public the exciting results of their research and attract young people, particularly women, into careers in science and technology. The objectives of this project are based on precise determinations of the orbits of numerous stars located as close to the black hole as possible. Because the density of stars at the Galactic center is exceptionally high, observations with the highest possible spatial resolution are essential. This project will employ adaptive optics with 10m telescopes at the W.M. Keck Observatory. Although the investigators have already obtained many years of data, this is a long-term project because the periods of the orbits range from tens to hundreds of years. Each additional year of data increases the accuracy of the orbits disproportionately because of the constantly improving observational technologies. The orbits will also be used to set strong limits on, or possibly measure, the abundance and distribution of dark matter around the black hole.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.

我们的银河系中心有一个超大质量黑洞（SMBH）。 研究人员多年来一直在观察围绕SMBH运行的单个恒星。研究人员利用这些观测结果研究了强引力和密集环境对这些恒星的影响。 他们的观测结果显示，正如预期的那样，恒星在SMBH周围移动得非常快。研究人员发现，SMBH附近的环境是可以通过地球观测研究的自然世界中最极端的环境。 这些观测与模型相结合，被用作理解支配我们宇宙的物理原理的实验室。 研究人员计划使用世界上最大的望远镜进行进一步的观测，以寻找只有在极端环境中才能检测到的引力新特性。 通过对恒星运动的精确测量，研究人员确定了SMBH的大小和距离。 到目前为止，他们的观测结果与爱因斯坦广义相对论的预测完全一致。 他们的新项目的目的是通过持续监测恒星在SMBH周围的运动来完善他们的相对论测试。 他们仔细测量恒星的位置会偏离经典的轨道描述多少。 他们将更精确地测量到银河系中心的距离，这决定了银河系的大小比例。 此外，他们预计银河系中心密集的恒星将成为双星，最终可能相互合并产生新的恒星。 有些最终会变成恒星大小的黑洞。 研究人员向公众宣传他们令人兴奋的研究成果，吸引年轻人，特别是妇女，从事科学和技术职业。该项目的目标是精确确定尽可能靠近黑洞的许多恒星的轨道。由于银河系中心的恒星密度非常高，因此必须进行尽可能高的空间分辨率的观测。该项目将采用自适应光学与10米望远镜在W. M。凯克天文台。虽然研究人员已经获得了多年的数据，但这是一个长期的项目，因为轨道的周期从几十年到几百年不等。由于观测技术的不断改进，每增加一年的数据都会不成比例地提高轨道的准确性。 这些轨道也将被用来设定严格的限制，或可能测量，黑洞周围暗物质的丰度和分布。这个奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

项目成果

The Orbital Eccentricities of Directly Imaged Companions Using Observable-based Priors: Implications for Population-level Distributions

使用基于可观察的先验的直接成像同伴的轨道偏心率：对群体水平分布的影响

• DOI: 10.3847/1538-3881/acdc9a
• 发表时间: 2023
• 期刊: The Astronomical Journal
• 作者: Do Ó, Clarissa R.;O’Neil, Kelly K.;Konopacky, Quinn M.;Do, Tuan;Martinez, Gregory D.;Ruffio, Jean-Baptiste;Ghez, Andrea M.
• 通讯作者: Ghez, Andrea M.

A Hidden Friend for the Galactic Center Black Hole, Sgr A*

• DOI: 10.3847/2041-8213/ab5e3b
• 发表时间: 2019-12
• 期刊: The Astrophysical Journal Letters
• 作者: S. Naoz;C. Will;E. Ramirez-Ruiz;A. Hees;A. Ghez;T. Do

The Star Formation History of the Milky Way’s Nuclear Star Cluster

银河系核星团的恒星形成历史

• DOI: 10.3847/1538-4357/aca8ad
• 发表时间: 2023
• 期刊: The Astrophysical Journal
• 作者: Chen, Zhuo;Do, Tuan;Ghez, Andrea M.;Hosek, Jr., Matthew W.;Feldmeier-Krause, Anja;Chu, Devin S.;Bentley, Rory O.;Lu, Jessica R.;Morris, Mark R.
• 通讯作者: Morris, Mark R.

Analyzing the Intrinsic Magnetic Field in the Galactic Center Radio Arc

• DOI: 10.3847/1538-4357/ac2cc4
• 发表时间: 2021-10
• 期刊: The Astrophysical Journal
• 作者: Dylan M. Par'e;C. Purcell;C. Lang;M. Morris;J. Green

An Optical Distortion Solution for the Keck I OSIRIS Imager

Keck I OSIRIS 成像仪的光学畸变解决方案

• DOI: 10.3847/1538-3881/aceaf7
• 发表时间: 2023
• 期刊: The Astronomical Journal
• 作者: Freeman, Matthew S. R.;Lu, Jessica R.;Lyke, Jim;Gautam, Abhimat;Kupke, Renate;Ghez, Andrea;Sakai, Shoko;Anderson, Jay;Bellini, Andrea
• 通讯作者: Bellini, Andrea