论文标题
核星簇中中间质量黑洞二进制的合并速率
Merger rates of intermediate-mass black hole binaries in nuclear star clusters
论文作者
论文摘要
恒星质量黑洞（BHS）的重复合并在致密星团中可以产生中间质量黑洞（IMBHS）。特别是，尽管由于引力辐射的各向异性发射，但星系中心的核恒星簇具有足够深的潜在井来保留大多数BH合并产品。这些事件可以在引力波（GWS）中检测到，这代表了揭示IMBH的前所未有的机会。在本文中，我们分析了广泛的数值模拟的统计结果，这些模拟包括不同的簇金属，初始BH种子质量和初始BH旋转，并计算IMBH二进制文件的合并速率。我们发现合并费率在$ 0.01 $ - $ 10 $ \，gpc $^{ - 3} $ \，yr $^{ - 1} $的情况下，取决于IMBH群众。我们还计算了基于地面和空间观测值中的多波段检测数量。我们的模型预测，每年应与Lisa，Decigo，ET和Ligo一起发现一些合并事件，其中包括Masses $ \ Lessim 1000 \ msun $，以及每年与Decigo，ET和Ligo的合并事件。
Repeated mergers of stellar-mass black holes (BHs) in dense star clusters can produce intermediate-mass black holes (IMBHs). In particular, nuclear star clusters at the centers of galaxies have deep enough potential wells to retain most of the BH merger products, in spite of the significant recoil kicks due to anisotropic emission of gravitational radiation. These events can be detected in gravitational waves (GWs), which represent an unprecedented opportunity to reveal IMBHs. In this paper, we analyze the statistical results of a wide range of numerical simulations, which encompass different cluster metallicities, initial BH seed masses, and initial BH spins, and we compute the merger rate of IMBH binaries. We find that merger rates are in the range $0.01$-$10$\,Gpc$^{-3}$\,yr$^{-1}$ depending on IMBH masses. We also compute the number of multi-band detections in ground-based and space-based observatories. Our model predicts that a few merger events per year should be detectable with LISA, DECIGO, ET, and LIGO for IMBHs with masses $\lesssim 1000\msun$, and a few tens of merger events per year with DECIGO, ET, and LIGO only.
