论文标题
三轴形状与暗物质光环的形成历史之间的相关性
Correlations between Triaxial Shapes and Formation History of Dark Matter Haloes
论文作者
论文摘要
暗物质光环的形状在通过即将进行的大规模结构调查来限制宇宙学方面起着至关重要的作用。在本文中，我们研究了Multidark Planck 2 N体宇宙学模拟中暗物质光环中三轴形状与地层历史之间的相关性。我们发现，光环椭圆度与光晕性能密切相关，后者是光环形成史的代理，例如晕晕浓度和峰含量偏移。特别是，光环椭圆度和光晕浓度之间的相关性几乎与光晕密度峰高度无关。我们提出了一个简单的模型，用于使用条件丰度匹配的光环椭圆度和浓度之间的相关性，并为三轴光环形状的多维分布提供拟合公式，这是光晕峰高度的函数。我们应用晕圈形状模型来衡量光环椭圆度和方向偏置对聚类大小晕圈中过量表面质量密度曲线的影响。我们的模型对于探索三轴光环形状对宇宙学限制的影响应该很有用。
The shape of dark matter haloes plays a critical role in constraining cosmology with upcoming large-scale structure surveys. In this paper, we study the correlations between the triaxial shapes and formation histories in dark matter haloes in the MultiDark Planck 2 N-body cosmological simulation. We find that halo ellipticity is strongly correlated with halo properties that serve as proxies of halo formation history, such as halo concentration and the peak-centroid offset. In particular, the correlation between halo ellipticity and halo concentration is nearly independent of the halo density peak height. We present a simple model for the correlation between halo ellipticity and concentration using conditional abundance matching, and provide fitting formulae for the multi-dimensional distributions of triaxial halo shape as a function of halo peak height. We apply our halo shape model to gauge the effects of halo ellipticity and orientation bias on the excess surface mass density profiles in cluster-size halos. Our model should be useful for exploring the impact of triaxial halo shape on cosmological constraints in upcoming weak lensing surveys of galaxy clusters.
