We explore the possibility that the recently detected black hole binary (BHB) merger event GW190521 originates from the first generation of massive, metal-free, so-called PopulationIII (Pop III) stars. Based on improved binary statistics derived from N-body simulations of PopIII star clusters, we calculate the merger rate densities of PopIII BHBs similar to GW190521, in two evolution channels: classical binary stellar evolution and dynamical hardening in high-redshift nuclear star clusters. Both channels can explain the observed rate density. However, the latter is favored by better agreement with observation and less restrictions on uncertain parameters. Our analysis also indicates that given the distinct features of the two channels, future observation of BHB mergers similar to GW190521 with third-generation gravitational wave detectors will greatly improve our knowledge of the evolution of PopIII BHBs, especially for their dynamics during cosmic structure formation.

我们探索了最近检测到的黑洞双星（BHB）合并事件GW190521来自第一代无金属的大质量所谓“人口III”（Pop III）星的可能性。基于源自N的改进的二进制统计量-PopIII恒星团的模拟，我们在两个演化通道中计算了与GW190521类似的PopIII BHBs的合并率密度：经典双星演化和高红移核星团中的动态硬化。两个通道都可以解释观察到的速率密度。但是，后者更好地与观察一致，并且对不确定参数的限制更少，因而受到青睐。我们的分析还表明，鉴于这两个通道的显着特征，与GW190521类似的BHB与第三代重力波探测器合并的未来观察将大大提高我们对PopIII BHBs演化的了解，尤其是它们在宇宙结构形成过程中的动力学。