论文标题
人口的重力波III二进制黑洞由动力捕获形成
Gravitational waves from Population III binary black holes formed by dynamical capture
论文作者
论文摘要
我们使用宇宙学流体动力模拟研究由动态捕获（Ex-Situ地层通道）形成的高红移二进制黑洞（BBHS）的重力波（GW）信号。我们特别关注的是BHS，源自第一代，金属贫困，所谓的人口〜III（POP〜III）星。在流行二元星星中出现了一种替代（原位）地层途径，其GW签名已被深入研究。在我们的乐观模型中，我们预测〜0.04 /（yr gpc^3）的Ex-Situ BBHS（Z> 4形成）的局部GW事件速率密度。这与原位bbhs的速率密度的保守预测相当，甚至是〜0.01-0.1 /（yr gpc^3）的速率密度，这表明EX-SITU地层通道可能与生产GW事件的现场渠道一样重要。我们还评估了对选定计划的GW仪器（例如爱因斯坦望远镜（ET））的模拟GW事件的可检测性。例如，我们发现ET的木琴构型的全天际检测率以高于10的信噪比为<100。但是，我们的结果对BBH识别和进化的子网格模型高度敏感，因此在悲观情况下，GW事件效率（速率）降低了4（20）倍。 POP III BBHS的前Situ通道值得进一步研究，以更好地建模POP III种子BHS周围的环境。
We use cosmological hydrodynamic simulations to study the gravitational wave (GW) signals from high-redshift binary black holes (BBHs) formed by dynamical capture (ex-situ formation channel). We in particular focus on BHs originating from the first generation of massive, metal-poor, so-called Population~III (Pop~III) stars. An alternative (in-situ) formation pathway arises in Pop~III binary stars, whose GW signature has been intensively studied. In our optimistic model, we predict a local GW event rate density for ex-situ BBHs (formed at z>4) of ~0.04 /(yr Gpc^3). This is comparable to or even higher than the conservative predictions of the rate density for in-situ BBHs ~0.01-0.1 /(yr Gpc^3), indicating that the ex-situ formation channel may be as important as the in-situ one for producing GW events. We also evaluate the detectability of our simulated GW events for selected planned GW instruments, such as the Einstein Telescope (ET). For instance, we find the all-sky detection rate with signal-to-noise ratios above 10 to be <100 per year for the xylophone configuration of ET. However, our results are highly sensitive to the sub-grid models for BBH identification and evolution, such that the GW event efficiency (rate) is reduced by a factor of 4 (20) in the pessimistic case. The ex-situ channel of Pop III BBHs deserves further investigation with better modeling of the environments around Pop III-seeded BHs.
