Peißker Florian, Zajaček Michal, Labadie Lucas, Bordier Emma, Eckart Andreas, Melamed Maria, Karas Vladimír
1.Physikalisches Institut, Universität zu Köln, Zülpicher Str. 77, Cologne, 50937, Germany.
Department of Theoretical Physics and Astrophysics, Masaryk University, Kotlářpská 2, Brno, 61137, Czech Republic.
Nat Commun. 2024 Dec 17;15(1):10608. doi: 10.1038/s41467-024-54748-3.
High-velocity stars and peculiar G objects orbit the central supermassive black hole (SMBH) Sagittarius A* (Sgr A*). Together, the G objects and high-velocity stars constitute the S cluster. In contrast with theoretical predictions, no binary system near Sgr A* has been identified. Here, we report the detection of a spectroscopic binary system in the S cluster with the masses of the components of 2.80 ± 0.50 M and 0.73 ± 0.14 M, assuming an edge-on configuration. Based on periodic changes in the radial velocity, we find an orbital period of 372±3 days for the two components. The binary system is stable against the disruption by Sgr A* due to the semi-major axis of the secondary being 1.59±0.01 AU, which is well below its tidal disruption radius of approximately 42.4 AU. The system, known as D9, shows similarities to the G objects. We estimate an age for D9 of yr that is comparable to the timescale of the SMBH-induced von Zeipel-Lidov-Kozai cycle period of about 10 yr, causing the system to merge in the near future. Consequently, the population of G objects may consist of pre-merger binaries and post-merger products. The detection of D9 implies that binary systems in the S cluster have the potential to reside in the vicinity of the supermassive black hole Sgr A* for approximately 10 years.
高速恒星和特殊的G天体围绕着中心超大质量黑洞人马座A*（Sgr A*）运行。G天体和高速恒星共同构成了S星团。与理论预测相反，尚未在Sgr A附近发现双星系统。在此，我们报告在S星团中检测到一个光谱双星系统，假设其为侧向配置，其组成部分的质量分别为2.80±0.50M和0.73±0.14M。基于径向速度的周期性变化，我们发现这两个组成部分的轨道周期为372±3天。由于次级天体的半长轴为1.59±0.01天文单位，远低于其约42.4天文单位的潮汐瓦解半径，该双星系统对被Sgr A瓦解具有稳定性。这个被称为D9的系统与G天体有相似之处。我们估计D9的年龄为 年，这与超大质量黑洞引发的冯·齐佩尔 - 利多夫 - 科扎伊循环周期的时间尺度约10年相当，这将导致该系统在不久的将来合并。因此，G天体群体可能由合并前的双星和合并后的产物组成。D9的发现意味着S星团中的双星系统有可能在超大质量黑洞Sgr A*附近存在约10年。
