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在S星团中的一个二进制星系,靠近超大质量黑洞射手座A星座

Florian Peißker¹, Michal Zajaček^2,3, Lucas Labadie²

¹1.Physikalisches Institut, Universität zu Köln, Zülpicher Str. 77, Cologne, 50937, Germany. peissker@ph1.uni-koeln.de.

Nature communications

|December 17, 2024

概括

天文学家在射手座A*附近发现了一颗稳定的双星系统D9,挑战了以前的理论. 这一发现表明G物体可能是合并前或合并后的二进制星体,影响我们对超大质量黑洞周围恒星动态的理解.

科学领域:

天体物理学天体物理学
恒星动力学恒星动力学
银河研究中心的研究中心.

背景情况:

高速度的恒星和特殊的G物体围绕S星团内的超大质量黑洞 (SMBH) 射手座A* (Sgr A*) 运行.
理论预测表明,Sgr A* 附近没有二进制星系.
在S星团中以前没有发现任何光谱二进制星系.

研究的目的:

报告在S星团内检测到一个光谱二进制星系.
描述这个二进制星系的特性及其在Sgr A*附近的稳定性.
调查这一发现对G物体的性质和SMBHs附近的恒星演变的影响.

主要方法:

通过分析辐射速度变化来检测光谱二进制系统.
确定组件质量和轨道周期 (372±3天).
基于其半主要轴 (1.59±0.01 AU) 和Sgr A*的潮破坏半径 (~42.4 AU) 的Sgr A*对抗潮破坏的系统稳定性的评估.

主要成果:

在S星团中检测到一个稳定的光谱二进制系统,被指定为D9.
组件质量被确定为2.80 ± 0.50 M和0.73 ± 0.14 M_0.
D9与已知的G物体有相似之处,并且在Sgr A*附近稳定,估计年龄与SMBH诱导的·泽佩尔-利多夫-科扎伊周期 (~10~6年) 相似.

结论:

发现D9挑战了关于Sgr A*附近没有二进制星系的先前假设.
G对象群可能包括合并前的二进制数据库和合并后的遗迹.
双星系统可以在Sgr A*附近长时间保持稳定 (大约10年).

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