发表机构
Tsinghua University; University of California; University of Maryland; New York University Abu Dhabi（清华大学; 加州大学; 马里兰大学; 纽约大学阿布扎比分校）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
利用 IllustrisTNG-300 模拟，研究发现中心恒星质量与卫星富度作为晕质量代理在群级质量上相似但组装历史不同，中心恒星质量-富度平面可有效选择具有特定吸积历史的暗物质晕。
AI 中文摘要
最近的观测表明，大质量暗物质晕的恒星成分与其组装历史之间存在内在联系。利用 IllustrisTNG-300 模拟中 $\log[M_{\rm halo}/M_\odot] \geq 13.0$ 的大质量暗物质晕，我们探讨了按中心星系恒星质量和卫星富度选择的样本之间次级晕属性的差异。对于群级质量，我们发现按中心星系 50 至 100 kpc 外围恒星质量（$M_{\star,[50,100]}$）选择的暗物质晕，其晕质量分布与按内在卫星富度（$\lambda_{10, R_{200}}$）选择的样本相似，但在组装历史上存在显著差异：$M_{\star,[50,100]}$ 选择的晕更集中且形成更早。在更高质量（$\sim10^{14}~M_\odot$）下，内在富度成为更好的晕质量代理，但仅在忽略投影效应时成立。我们发现，当两个代理具有相似的离散度时，差异集检验能最有效地选择可比的晕质量样本。投影效应和重子物理不改变主要趋势，但对观测应用仍是重要的注意事项。我们的发现表明，中心恒星质量-富度平面是选择具有特定吸积历史的晕的强大工具，为深场成像和精密透镜巡天（如 Euclid 和 LSST）时代的星系-晕联系提供了新见解。
英文摘要
Recent observations suggest intrinsic links between the stellar components of massive halos and their assembly histories. Using massive halos with $\log[M_{\rm halo}/M_\odot] \geq 13.0$ from the IllustrisTNG-300 simulation, we explore differences in secondary halo properties between samples selected by central galaxy stellar mass and satellite richness. For group-like masses, we find that halos selected by the outskirts stellar mass of their central galaxies between 50 and 100 kpc ($M_{\star,[50,100]}$) have similar halo mass distributions to those selected by intrinsic satellite richness ($λ_{10, R_{200}}$), but differ significantly in assembly history: $M_{\star,[50,100]}$-selected halos are more concentrated and formed earlier. At higher masses ($\sim10^{14}~M_\odot$), intrinsic richness becomes the better halo-mass proxy, but only when projection effects are ignored. We find that the difference-set test selects comparable halo-mass samples most effectively when the two proxies have similar scatter. Projection effects and baryonic physics do not alter the main trends but remain important caveats for observational applications. Our findings show that the central stellar mass-richness plane is a powerful tool for selecting halos with particular accretion histories, offering new insights into the galaxy-halo connection in the era of deep imaging and precision lensing surveys such as Euclid and LSST.
Comments24 pages, 15 figures, 1 table, submitted to ApJ
