Dynamically formed black hole (BH) binaries (BBHs) are important sources of gravitational waves (GWs). Globular clusters (GCs) provide a major environment to produce such BBHs, but the total mass of the known GCs is small compared to that in the Galaxy; thus, the fraction of BBHs formed in GCs is also small. However, this assumes that GCs contain a canonical initial mass function (IMF) similar to that of field stars. This might not be true because several studies suggest that extreme dense and metal-poor environment can result in top-heavy IMFs, where GCs may originate. Although GCs with top-heavy IMFs were easily disrupted or have become dark clusters, the contribution to the GW sources can be significant. Using a high-performance and accurate $N$-body code, \textsc{petar}, we investigate the effect of varying IMFs by carrying out four star-by-star simulations of dense GCs with the initial mass of $5\times10^5 M_\odot$ and the half-mass radius of $2$~pc. We find that the BBH merger rate does not monotonically correlate with the slope of IMFs. Due to a rapid expansion, top-heavy IMFs lead to less efficient formation of merging BBHs. The formation rate continuously decreases as the cluster expands because of the dynamical heating caused by BHs. However, in star clusters with a top-heavier IMF, the total number of BHs is larger, and therefore, the final contribution to merging BBHs can still be more than from clusters with the standard IMF, if the initial cluster mass and density is higher than those used in our model.
Eccentricity Distribution for Dynamical Gravitational-Wave Merger Channels in The Pinhole Regime
Institute for Advanced Study（高等研究院）；University of Cambridge（剑桥大学）；Gonville & Caius College（贡维尔与凯斯学院）；Princeton University（普林斯顿大学）；Cardiff University（卡迪夫大学）；Niels Bohr International Academy, The Niels Bohr Institute（尼尔斯·玻尔国际学院，尼尔斯·玻尔研究所）
Superradiant and dynamical spin-down of neutron stars with gravitational wave implications
Institute of Mathematical Sciences, HBNI（马哈拉施特拉数学科学研究所）；Homi Bhabha National Institute（霍米·巴巴国立研究所）；Indian Institute of Science Education and Research Berhampur（布赫纳普尔印度科学教育与研究学院）
Dynamical tides in coalescing superfluid neutron star binaries with hyperon cores and their detectability with third generation gravitational-wave detectors
Environmental effects in stellar mass gravitational wave sources I: Expected fraction of signals with significant dephasing in the dynamical and AGN channels
Dynamical tidal response of neutron stars: From effective field theory to gravitational waveforms
Université Paris Cité（巴黎西岱大学）；CNRS（法国国家科学研究中心）；Johns Hopkins University（约翰斯·霍普金斯大学）；Università di Pisa（比萨大学）；INFN, Sezione di Pisa（意大利国家核物理研究所比萨分部）；Sapienza Università di Roma（罗马第一大学）；INFN, Sezione di Roma（意大利国家核物理研究所罗马分部）
Merger rates in primordial black hole clusters without initial binaries
原始的黑洞通过宇宙密度波动的崩溃而形成，被假设为宇宙中暗物质含量的贡献者。与此同时，它们的合并可能有助于最近观察到的引力波源的数量。我们调查的情况下，原始黑洞形成双星在宇宙的后期。具体来说，我们重新审视合并的原始黑洞在小集群的~30个对象的初始双星的情况下。双星通过牛顿引力相互作用动态地形成。这些双星作为星系团的热源，增加了星系团的速度色散，这抑制了通过引力波两体捕获的直接合并。与此同时，紧密双星的三体相遇太罕见了，以至于无法使双星足够紧密，从而使它们通过引力波辐射合并。我们的结论是，在没有初始双星的情况下，Bird et al.（2016）初始星团配置中的原始黑洞的合并率至少比以前提出的低一个数量级，这使得引力波检测到这样的源是不可能的。
