LCDM宇宙中孤立宿主星系周围不对称的卫星星系分布
Lopsided Satellite Distributions around Isolated Host Galaxies in a LCDM Universe
AI总结：
利用LCDM模拟红移巡天和与观测一致的选择标准，本文证实孤立宿主的卫星星系存在显著单侧分布，且该效应不能由样本不完备、误认或晚期吸积解释。
摘要：
最近一项观测研究发现，明亮、孤立宿主星系的卫星星系投影空间分布相对于宿主位置往往呈现不对称性。本文考察了大量明亮、孤立宿主星系的卫星星系空间分布，这些星系来自LCDM模拟的模拟红移巡天。宿主星系及其卫星星系采用与该观测研究完全相同的选择标准进行识别，从而可以直接比较模拟系统和观测系统的结果。为表征卫星星系的空间分布，我们采用两个统计量：[1]卫星星系的成对聚集，以及[2]平均合成长度（Mean Resultant Length）。与观测研究一致，我们发现模拟中的卫星星系强烈倾向于位于其宿主的同一侧，并且该信号对于蓝色宿主的卫星星系最为显著。这些不对称的卫星星系分布并不能仅仅归因于观测卫星星系表的不完备性，或被错误识别为卫星星系的天体的存在。此外，在遥远过去（> 8 Gyr）加入宿主晕的卫星星系在其空间分布中表现出明显的不对称性，因此，这种不对称性并不能仅仅归因于晚期的卫星星系吸积。
英文摘要：
A recent observational study found that the projected spatial distributions of the satellites of bright, isolated host galaxies tend to be lopsided with respect to the locations of the hosts. Here, we examine the spatial distributions of the satellites of a large number of bright, isolated host galaxies that were obtained from mock redshift surveys of a LCDM simulation. Host galaxies and their satellites were identified using selection criteria that are identical to those used in the observational study, allowing a direct comparison of the results for the simulated and observed systems. To characterize the spatial distribution of the satellites, we adopt two statistics: [1] the pairwise clustering of the satellites and [2] the Mean Resultant Length. In agreement with the observational study, we find a strong tendency for satellites in the simulation to be located on the same side of their host, and the signal is most pronounced for the satellites of blue hosts. These lopsided satellite distributions are not solely attributable to incompleteness of the observed satellite catalog or the presence of objects that have been falsely identified as satellites. In addition, satellites that joined their hosts' halos in the distant past (> 8 Gyr) show a pronounced lopsidedness in their spatial distributions and, therefore, the lopsidedness is not solely attributable to late-time accretion of satellites.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
