The Fifth Candidate for an Intermediate-mass Black Hole in the Galactic Center
The Fifth Candidate for an Intermediate-mass Black Hole in the Galactic Center
复制标题
DOI：
10.3847/1538-4357/ab6f6f
复制
发表时间：
2020-02
期刊：
影响因子：
--
通讯作者：
S. Takekawa;T. Oka;Y. Iwata;Shiho Tsujimoto;Mariko Nomura
中科院分区：
文献类型：
--
作者：
S. Takekawa;T. Oka;Y. Iwata;Shiho Tsujimoto;Mariko Nomura
本文报道了利用阿塔卡马大型毫米/亚毫米阵列对高速致密云HCN-0.085-0.094进行高分辨率分子线观测的结果。HCN J = 4-3、HCO+ J = 4-3和CS J = 7-6线图像显示，HCN - 0.085 - 0.094主要由3个速度宽度极宽的小团块组成。这三个团块中的每一个都在朝向Sgr a *的外围有一个5.5 GHz的无线电连续体。位置关系表明，它们的表面已经被中心星团中年轻恒星发出的紫外线光子电离，这表明这些星团离银河核很近。三个团块中的一个团块具有非常陡峭的速度梯度的环状结构。这一运动学结构表明它的轨道围绕着一个质量为~ 104 M⊙的点状天体。没有对应的恒星表明这个点状物体可能是一个静止的黑洞。这一发现在我们银河系的中心区域增加了另一个中等质量黑洞的候选者。
We report the results of high-resolution molecular line observations of the high-velocity compact cloud HCN–0.085–0.094 with the Atacama Large Millimeter/submillimeter Array. The HCN J = 4–3, HCO+ J = 4–3, and CS J = 7–6 line images reveal that HCN–0.085–0.094 consists mainly of three small clumps with extremely broad velocity widths. Each of the three clumps has a 5.5 GHz radio continuum counterpart in its periphery toward Sgr A*. The positional relationship indicates that their surfaces have been ionized by ultraviolet photons from young stars in the central cluster, suggesting the clumps are in close proximity to the Galactic nucleus. One of the three clumps has a ring-like structure with a very steep velocity gradient. This kinematical structure suggests an orbit around a point-like object with a mass of ∼104 M⊙. The absence of stellar counterparts indicates that the point-like object may be a quiescent black hole. This discovery adds another intermediate-mass black hole candidate in the central region of our Galaxy.