During the first three observing runs of the Advanced gravitational-wave detector network, the LIGO/Virgo collaboration detected several black hole binary (BHBH) mergers. As the population of detected BHBH mergers grows, it will become possible to constrain different channels for their formation. Here we consider the chemically homogeneous evolution (CHE) channel in close binaries, by performing population synthesis simulations that combine realistic binary models with detailed cosmological calculations of the chemical and star-formation history of the Universe. This allows us to constrain population properties, as well as cosmological and aLIGO detection rates of BHBH mergers formed through this pathway. We predict a BHBH merger rate at redshift zero of $5.8 \hspace{1mm} \textrm{Gpc}^{-3} \textrm{yr}^{-1}$ through the CHE channel, to be compared with aLIGO's measured rate of ${53.2}_{-28.2}^{+55.8} \hspace{1mm} \text{Gpc}^{-3}\text{yr}^{-1}$, and find that eventual merger systems have BH masses in the range $17 - 43 \hspace{1mm} \textrm{M}_{\odot}$ below the pair-instability supernova (PISN) gap, and $>124 \hspace{1mm} \textrm{M}_{\odot}$ above the PISN gap. We further investigate the effects of momentum kicks during black hole formation, calculate cosmological and magnitude limited PISN rates and investigate the effects of high-redshift deviations in the star formation rate. We find that momentum kicks tend to increase delay times of BHBH systems, and our magnitude limited PISN rate estimates indicate that current deep surveys should be able to detect such events. Lastly, we find that our cosmological merger rate estimates change by at most $\sim 8\%$ for mild deviations of the star formation rate in the early Universe, and by up to $\sim 40\%$ for extreme deviations.

中文翻译：

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来自化学同质二元演化的黑洞合并和对不稳定性超新星的宇宙速率

在高级引力波探测器网络的前三轮观测中，LIGO/Virgo 合作探测到了几次黑洞双星 (BHBH) 合并。随着检测到的 BHBH 合并数量的增长，限制其形成的不同渠道将成为可能。在这里，我们通过执行人口合成模拟，将现实的双星模型与宇宙化学和恒星形成历史的详细宇宙学计算相结合，来考虑紧密双星中的化学均质演化 (CHE) 通道。这使我们能够限制种群特性，以及通过该途径形成的 BHBH 合并的宇宙学和 aLIGO 检测率。我们通过 CHE 通道预测 BHBH 合并率在 5.8 美元的红移零值 \hspace{1mm} \textrm{Gpc}^{-3} \textrm{yr}^{-1}$，与 aLIGO 的测量速率 ${53.2}_{-28.2}^{+55.8} \hspace{1mm} \text{Gpc}^{-3}\text{yr}^{-1}$ 进行比较，以及发现最终的合并系统的 BH 质量在 $17 - 43 \hspace{1mm} \textrm{M}_{\odot}$ 低于对不稳定性超新星 (PISN) 间隙，并且 $>124 \hspace{1mm} \textrm{M}_{\odot}$ 高于 PISN 差距。我们进一步研究了黑洞形成过程中动量踢的影响，计算了宇宙学和幅度限制的 PISN 率，并研究了高红移偏差对恒星形成率的影响。我们发现动量踢往往会增加 BHBH 系统的延迟时间，我们对 PISN 率的幅度限制估计表明，当前的深度调查应该能够检测到此类事件。最后，