Hyper-velocity and tidal stars from binaries disrupted by a massive Galactic black hole
Hyper-velocity and tidal stars from binaries disrupted by a massive Galactic black hole
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作者：
J. Hills
一个紧密结合的双星与一个106 M⊙黑洞的紧密相遇会导致双星的一个组成部分与黑洞结合，而另一个组成部分会以高达4000 km−1的速度被抛出。即使只发现一颗来自银河系中心的超高速恒星，也几乎是巨大黑洞存在的确凿证据。黑洞的新伴星具有很高的轨道速度，随着其轨道因潮汐耗散而缩小，轨道速度进一步增加。这种潮汐恒星的轨道收缩所释放的引力能可以与它释放的总核能相媲美。
A close but newtonian encounter between a tightly bound binary and a 106 M⊙ black hole causes one binary component to become bound to the black hole and the other to be ejected at up to 4,000 km−1. The discovery of even one such hyper-velocity star coming from the Galactic centre would be nearly definitive evidence for a massive black hole. The new companion of the black hole has a high orbital velocity which increases further as its orbit shrinks by tidal dissipation. The gravitational energy released by the orbit shrinkage of a such a tidal star can be comparable to its total nuclear energy release.