论文标题
裸眼三重系统，内部二进制中有一个无刺激的黑洞
A naked-eye triple system with a nonaccreting black hole in the inner binary
论文作者
论文摘要
几十个光学梯形光谱表明HR 6819是分层三重。经典的恒星位于宽阔的轨道上，其内部40 d二进制围绕不受约束的周期，该二进制由B3 III恒星组成，在圆形轨道中是看不见的伴侣。径向速度的半振幅为61.3 km/s的内星，其最小（可能）5.0 msun（6.3 +-0.7 msun）的质量表示> = 4.2 msun（> = 5.0 +-0.4 msun）的质量，即> = 4.2 msun（> = 5.0 +-0.4 msun），即，是一个。光谱时间序列与LB-1的观察非常相似。 LB-1的类似三星级结构将LB-1中BH的质量从〜70 MSUN降低到更典型的银河恒星残余BHS的水平。 HR 6819中的BH可能是距太阳最接近的BH，与LB-1一起表明了一群安静的BHS。对于合并双BHS或BH + Neutron Star二进制组的模型，其嵌入在分层三重结构中可能是感兴趣的。其他带有外部BE恒星的三星星，但没有BH。通过剥离，这样的系统可能成为单个恒星的来源。
Several dozen optical echelle spectra demonstrate that HR 6819 is a hierarchical triple. A classical Be star is in a wide orbit with an unconstrained period around an inner 40 d binary consisting of a B3 III star and an unseen companion in a circular orbit. The radial-velocity semi-amplitude of 61.3 km/s of the inner star and its minimum (probable) mass of 5.0 Msun (6.3 +- 0.7 Msun) imply a mass of the unseen object of >= 4.2 Msun (>= 5.0 +- 0.4 Msun), that is, a black hole (BH). The spectroscopic time series is stunningly similar to observations of LB-1. A similar triple-star architecture of LB-1 would reduce the mass of the BH in LB-1 from ~70 Msun to a level more typical of Galactic stellar remnant BHs. The BH in HR 6819 probably is the closest known BH to the Sun, and together with LB-1, suggests a population of quiet BHs. Its embedment in a hierarchical triple structure may be of interest for models of merging double BHs or BH + neutron star binaries. Other triple stars with an outer Be star but without BH are identified; through stripping, such systems may become a source of single Be stars.
