论文标题
避免剧集灾难：保留效率和二进制黑洞质谱
Avoiding a Cluster Catastrophe: Retention Efficiency and the Binary Black Hole Mass Spectrum
论文作者
论文摘要
通过重力波鉴定的二元黑洞合并的种群发现了宇宙黑洞内在特性的意外特征。一个尤其令人惊讶和令人兴奋的结果是在配对质量间隙中可能存在黑洞，$ \ sim50-120〜m_ \ odot $。密集的恒星环境可以通过分层合并填充质量空间区域，黑洞合并产品的保留效率很大程度上取决于宿主环境的逃逸速度。我们使用简单的玩具模型来表示各种动态环境中的层次合并方案。我们发现，在具有高逃逸速度的环境中的层次合并$（\ gtrsim300〜 \ mathrm {km \，s}^{ - 1}）$有效地保留。如果这样的环境主导了二进制黑洞的合并率，这将导致大量的高质量合并，这些合并可能与当前二进制黑洞合并目前目录的经验质谱不相容。因此，必须调整有效产生层次合并并对观察到的人群产生重大贡献的模型，以避免在配对稳定质量间隙内外造成过度产生二进制黑洞合并过量的“群集灾难”。
The population of binary black hole mergers identified through gravitational waves has uncovered unexpected features in the intrinsic properties of black holes in the universe. One particularly surprising and exciting result is the possible existence of black holes in the pair-instability mass gap, $\sim50-120~M_\odot$. Dense stellar environments can populate this region of mass space through hierarchical mergers, with the retention efficiency of black hole merger products strongly dependent on the escape velocity of the host environment. We use simple toy models to represent hierarchical merger scenarios in various dynamical environments. We find that hierarchical mergers in environments with high escape velocities $(\gtrsim300~\mathrm{km\,s}^{-1})$ are efficiently retained. If such environments dominate the binary black hole merger rate, this would lead to an abundance of high-mass mergers that is potentially incompatible with the empirical mass spectrum from the current catalog of binary black hole mergers. Models that efficiently generate hierarchical mergers, and contribute significantly to the observed population, must therefore be tuned to avoid a "cluster catastrophe" of overproducing binary black hole mergers within and above the pair-instability mass gap.
