标题： 对辐射驱动双黑洞捕获事件速率的观测限制 显示英文标题

标题： Observational limits on the rate of radiation-driven binary black hole capture events

摘要： 密集的天体物理环境，如球状星团和银河核区，可以容纳黑洞的双曲线相遇，这可能导致由引力波驱动的捕获。 有几个天体物理模型预测，二元黑洞合并的一部分来自于这些辐射驱动的捕获情景。 在本文中，我们介绍了对O3（LIGO和Virgo的第三次观测运行）中引力波驱动捕获事件的搜索灵敏度。 我们使用由数值相对论模拟产生的捕获波形，覆盖了四种不同的质量比，并且至少有两种不同的初始角动量值（每个质量比）。 我们采用了O3中最通用的短时暂态搜索方法，以可见时空体积为指标，在总质量的广泛范围内评估该参数空间中的搜索灵敏度。 从可见时空体积中，我们首次确定了此类系统的合并率上限。 在90%置信度下最严格的率上限估计为$0.2~\mathrm{Gpc}^{-3}\,\mathrm{yr}^{-1}$对于一个等质量的$200~M_\odot$二元系统。 此外，在最近的研究中，事件GW190521被认为是一个捕获事件。 根据对GW190521的这种解释，我们发现类似事件的合并率为$0.47~\mathrm{Gpc}^{-3}\,\mathrm{yr}^{-1}$。 显示英文摘要

摘要： Dense astrophysical environments like globular clusters and galactic nuclei can host hyperbolic encounters of black holes which can lead to gravitational-wave driven capture. There are several astrophysical models which predict a fraction of binary black hole mergers to come from these radiation-driven capture scenarios. In this paper we present the sensitivity of a search towards gravitational-wave driven capture events for O3, the third observing run of LIGO and Virgo. We use capture waveforms produced by numerical relativity simulations covering four different mass ratios and at least two different values of initial angular momentum per mass ratio. We employed the most generic search for short-duration transients in O3 to evaluate the search sensitivity in this parameter space for a wide range in total mass in terms of visible spacetime volume. From the visible spacetime volume we determine for the first time the merger rate upper limit of such systems. The most stringent estimate of rate upper limits at 90\% confidence is $0.2~\mathrm{Gpc}^{-3}\,\mathrm{yr}^{-1}$ for an equal mass $200~M_\odot$ binary. Furthermore, in recent studies the event GW190521 has been suggested to be a capture event. With this interpretation of GW190521, we find the merger rate of similar events to be $0.47~\mathrm{Gpc}^{-3}\,\mathrm{yr}^{-1}$.