One of the crucial windows for distinguishing astrophysical black holes from primordial black holes is through the redshift evolution of their respective merger rates. The low redshift population of black holes of astrophysical origin is expected to follow the star formation rate. The corresponding peak in their merger rate peaks at a redshift smaller than that of the star formation rate peak (zp ≈ 2), depending on the time delay between the formation and mergers of black holes. Black holes of primordial origin are going to be present before the formation of the stars, and the merger rate of these sources at high redshift is going to be large. We propose a joint estimation of a hybrid merger rate from the stochastic gravitational wave background, which can use the cosmic history of merger rates to distinguish between the two populations of black holes. Using the latest bounds on the amplitude of the stochastic gravitational wave background amplitude from the third observation run of LIGO/Virgo, we obtain weak constraints at $68{{\ \rm per\ cent}}$ C.L. on the primordial black hole merger rate index $2.56_{-1.76}^{+1.64}$ and astrophysical black hole time delay $6.7_{-4.74}^{+4.22}$ Gyr. We should be able to distinguish between the different populations of black holes with the forthcoming O5 and A+ detector sensitivities.

中文翻译：

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我们可以通过随机引力波背景区分天体物理学和原始黑洞吗？

区分天体物理黑洞和原始黑洞的关键窗口之一是通过它们各自合并率的红移演化。天体物理起源的黑洞的低红移种群预计将跟随恒星形成率。其合并率的相应峰值在小于恒星形成率峰值（zp≈2）的红移处达到峰值，这取决于黑洞形成和合并之间的时间延迟。原始起源的黑洞将在恒星形成之前出现，这些来源在高红移处的合并率将会很大。我们建议从随机引力波背景中联合估计混合合并率，它可以利用合并率的宇宙历史来区分两个黑洞种群。使用来自 LIGO/Virgo 第三次观测运行的随机引力波背景振幅的最新界限，我们在原始黑洞合并率指数上获得了 $68{{\ \rm per\ cent}}$CL 的弱约束$2.56_{-1.76}^{+1.64}$ 和天体黑洞时间延迟 $6.7_{-4.74}^{+4.22}$ Gyr. 我们应该能够用即将推出的 O5 和 A+ 探测器灵敏度区分不同的黑洞群。64}$ 和天体黑洞时间延迟 $6.7_{-4.74}^{+4.22}$ Gyr. 我们应该能够用即将推出的 O5 和 A+ 探测器灵敏度区分不同的黑洞群。64}$ 和天体黑洞时间延迟 $6.7_{-4.74}^{+4.22}$ Gyr. 我们应该能够用即将推出的 O5 和 A+ 探测器灵敏度区分不同的黑洞群。