标题： 重子物理和中微子自由流效应分开及共同作用对大尺度结构的影响 显示英文标题

标题： The separate and combined effects of baryon physics and neutrino free-streaming on large-scale structure

摘要： 我们使用cosmo-OWLS和BAHAMAS宇宙学流体力学模拟组来探讨重子物理（特别是活动星系核AGN反馈）和大质量中微子自由流对大尺度结构的单独影响及联合影响。我们重点关注五个诊断指标：i）晕质量函数；ii）晕质量密度分布；iii）晕质量-集中关系；iv）晕聚类；以及v）物质聚类，并研究了重子物理效应和中微子自由流效应独立处理的程度。与先前的研究一致，我们发现AGN反馈和中微子自由流都抑制了总物质功率谱，尽管它们的尺度和红移依赖性存在显著差异。AGN反馈可以显著降低星团和星系团的质量，同时增加其标度半径。这些效应导致了质量-集中关系幅度的下降和固定质量下晕自相关函数的上升。中微子同样降低了星团和星系团的质量，但对其密度分布形状没有显著影响（因此也以类似反馈的方式影响质量-集中关系和晕聚类）。我们表明，在所有五个诊断指标上，重子物理和中微子自由流的综合效应可以通过将这些过程独立处理（即，将它们的单独效应相乘）通常估计到百分之几的精度，且仅有少数例外。 显示英文摘要

摘要： We use the cosmo-OWLS and BAHAMAS suites of cosmological hydrodynamical simulations to explore the separate and combined effects of baryon physics (particularly feedback from active galactic nuclei, AGN) and free-streaming of massive neutrinos on large-scale structure. We focus on five diagnostics: i) the halo mass function; ii) halo mass density profiles; iii) the halo mass-concentration relation; iv) the clustering of haloes; and v) the clustering of matter; and we explore the extent to which the effects of baryon physics and neutrino free-streaming can be treated independently. Consistent with previous studies, we find that both AGN feedback and neutrino free-streaming suppress the total matter power spectrum, although their scale and redshift dependencies differ significantly. The inclusion of AGN feedback can significantly reduce the masses of groups and clusters, and increase their scale radii. These effects lead to a decrease in the amplitude of the mass-concentration relation and an increase in the halo autocorrelation function at fixed mass. Neutrinos also lower the masses of groups and clusters while having no significant effect on the shape of their density profiles (thus also affecting the mass-concentration relation and halo clustering in a qualitatively similar way to feedback). We show that, with only a small number of exceptions, the combined effects of baryon physics and neutrino free-streaming on all five diagnostics can be estimated to typically better than a few percent accuracy by treating these processes independently (i.e., by multiplying their separate effects).