During the formation of the Milky Way, > 100 central black holes (BHs) may have been ejected from their small host galaxies as a result of asymmetric gravitational wave emission. We previously showed that many of these BHs are surrounded by a compact cluster of stars that remained bound to the BH during the ejection process. In this paper, we perform long term N-body simulations of these star clusters to determine the distribution of stars in these clusters today. These numerical simulations, reconciled with our Fokker-Planck simulations, show that stellar density profile follows a power-law with slope ~ -2.15, and show that large angle scattering and tidal disruptions remove 20 - 90% of the stars by ~10^10 yr. We then analyze the photometric and spectroscopic properties of recoiled clusters accounting for the small number of stars in the clusters. We use our results to perform a systematic search for candidates in the Sloan Digital Sky Survey. We find no spectroscopic candidates, in agreement with our expectations from the completeness of the survey. Using generic photometric models of present day clusters we identify ~100 recoiling cluster candidates. Follow-up spectroscopy would be able to determine the nature of these candidates.
Statistics of Satellite Galaxies Around Milky Way-Like Hosts
计算了标准宇宙学模型中类银河晕具有观测到的麦哲伦云数的概率。在LCDM模型中的MC的数量的统计是在一个大样本的SDSS星系的观测符合得很好。在星系r-波段光度和晕内速度v_max之间存在小散射关系的子晕丰度匹配假设下，我们与Liu等人（2010）使用SDSS DR 7数据进行的类似测量进行了详细比较。模型和观测数据给出了非常相似的概率，有零个，一个和两个MC样卫星。在这两种情况下，银河系光度宿主只有\sim 10%的机会拥有两颗类似于麦哲伦云的卫星。此外，我们提出了一个预测的概率为一个主机星系Nsats卫星星系作为一个函数的大小的主机和卫星。这种概率及其与宿主属性的比例与质量选择物体的概率有很大不同，因为质量-光度关系中的散射以及恒星形成效率随晕质量的变化。
Too Many, Too Few, or Just Right? The Predicted Number and Distribution of Milky Way Dwarf Galaxies
通过对观测到的SDSS矮星系群的完全性修正，我们预测了DES和LSST巡天中发现的银河系矮星系的空间分布和数量。我们应用最大规模的在过去，最早的形成，最早的坠落玩具模型，一组暗物质模拟银河系/M31晕对探索本地体积模拟（ELVIS）。观测到的银河系矮星系在LSST时代的空间分布将区分最早的陷落和矮星系如何填充暗物质subhalos的其他简化模型。包括所有的玩具模型和模拟，在90%的置信度下，我们预测在300 kpc内总共有37-114 L $\gtrsim 10^3$ L $_{\odot}$侏儒和131-782 L $\lesssim 10^3$ L $_{\odot}$侏儒。这些L $\gtrsim 10^3$ L $_{\odot}$矮星的数量比以前的预测要低得多，这主要是因为我们使用了更新的探测极限，并且每个天空区域发现的SDSS矮星的数量越来越少。对于25.8 mag的有效$r_{\rm limit}$，我们预测：DES的3-13 L $\gtrsim 10^3$ L $_{\odot}$和9-99 L $\lesssim 10^3$ L $_{\odot}$侏儒，LSST的18-53 L $\gtrsim 10^3$ L $_{\odot}$和53-307 L $\lesssim 10^3$ L $_{\odot}$侏儒。这些巨大的预测范围确保了未来十年的近场兴奋与这些…
