发表机构
Case Western Reserve University; Universidad de Sevilla; Institut de Física d’Altes Energies; Alma Mater Studiorum Università di Bologna; INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna; INFN-Sezione di Bologna（凯斯西储大学; 塞维利亚大学; 高能物理研究所; 博洛尼亚大学; 博洛尼亚天文空间科学研究所; 博洛尼亚意大利国家核物理研究所）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
该研究利用AIDA-TNG模拟，发现组装偏置在四种暗物质模型中差异很小，为替代暗物质模型下的星系-晕连接研究提供了稳健基线。
AI 中文摘要
暗物质晕的成团性不仅取决于晕质量，还取决于晕的次级属性，这一现象被称为晕组装偏置。结合晕占据数的变化，这种依赖性会影响星系的成团性，这一效应被称为星系组装偏置。尽管先前的研究发现，在ΛCDM框架内组装偏置对宇宙学的依赖性较弱，但其对底层暗物质物理的敏感性在很大程度上仍未得到探索。我们使用AIDA-TNG套件中匹配的纯暗物质和流体动力学模拟，测量了四种暗物质模型中的组装偏置：冷暗物质、温暗物质，以及具有恒定截面和速度依赖截面的自相互作用暗物质。我们发现，在z = 0时，对于浓度选择的晕，四种模型的晕组装偏置几乎相同，晕占据分布的浓度依赖性也是如此。由此产生的星系组装偏置信号同样仅表现出微弱的模型依赖性。对于z = 0处恒星质量选择的星系样本，其数密度为n = 0.0586 h^3 Mpc^{-3}，速度依赖的自相互作用暗物质情景与基准冷暗物质模型的偏差最大：其对星系成团性的组装偏置贡献增强高达约6%，对应于组装偏置振幅约3%的差异。尽管在统计上可区分，但这种差异很小，不太可能在当前的分析中被探测到。这种微弱的模型依赖性在不同星系数密度和红移下持续存在。总体而言，在TNG星系形成框架内，这些结果表明组装偏置在很大程度上对所探索的暗物质模型不敏感，为未来在替代暗物质情景中研究星系-晕连接提供了稳健的基线。
英文摘要
The clustering of dark matter halos depends not only on halo mass but also on secondary halo properties, a phenomenon known as halo assembly bias. Coupled with variations in halo occupation, this dependence impacts galaxy clustering, an effect termed galaxy assembly bias. While previous studies have found only weak cosmological dependence of assembly bias within the $Λ$CDM framework, its sensitivity to the underlying dark matter physics remains largely unexplored. We use the matched dark-matter-only and hydrodynamical simulations from the AIDA-TNG suite to measure assembly bias across four dark matter models: cold dark matter, warm dark matter, and self-interacting dark matter with constant cross-sections and velocity-dependent cross-sections. We find that at z = 0, halo assembly bias is nearly identical across the four models for concentration-selected halos, as is the concentration dependence of the halo occupation distribution. The resulting galaxy assembly bias signals likewise show only weak model dependence. For stellar-mass-selected galaxy samples with $n = 0.0586 h^{3} Mpc^{-3}$ at z = 0, the velocity-dependent self-interacting dark matter scenario exhibits the largest deviation from the fiducial cold dark matter model: its assembly bias contribution to galaxy clustering is enhanced by up to $\sim 6\%$, corresponding to a $\sim 3\%$ difference in the assembly bias amplitude. Although statistically distinguishable, this difference is small and unlikely to be detected in current analyses. The weak model dependence persists across different galaxy number densities and redshifts. Overall, within the TNG galaxy-formation framework, these results indicate that assembly bias is largely insensitive to the dark matter models explored here, providing a robust baseline for future studies of the galaxy-halo connection in alternative dark matter scenarios.
Comments12 pages, 9 figures, submitted to A&A
