Cold dark matter haloes in the Planck era: evolution of structural parameters for Einasto and NFW profiles
Cold dark matter haloes in the Planck era: evolution of structural parameters for Einasto and NFW profiles
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DOI：
10.1093/mnras/stu742
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发表时间：
2014-07-11
影响因子：
4.8
通讯作者：
Maccio, Andrea V.
中科院分区：
文献类型：
--
作者：
Dutton, Aaron A.;Maccio, Andrea V.
我们介绍了普朗克卫星宇宙学中弛豫冷暗物质(CDM)晕结构的演化。我们的模拟覆盖了50年的晕质量，从矮小星系到星系团。由于物质密度和功率谱归一化程度的提高，在红移z=0时，普朗克宇宙学中的浓度-质量关系比Wilkinson微波各向异性探测器宇宙学中的归一化系数高出20%。我们确认，Einasto轮廓可以更好地描述CDM晕；例如，在星系半光半径附近的尺度上，CDM晕的密度剖面比Navarro-Frenk-White(NFW)拟合所暗示的要陡峭得多。在固定晕质量下，Einasto形状参数有一个类似于0.2Dex的散射，进一步增加了CDM晕廓线的多样性。在我们的模拟中，浓度-质量关系的演变不能被文献中的任何分析模型再现。因此，我们提供了一个简单的拟合公式，它准确地描述了NFW和Einasto拟合的红移z=5和0之间的演化。最后，观测到的低红移螺旋星系、星系团和星系团的浓度和晕质量与我们的模拟很好地一致，这表明在这些尺度上对星系形成只有温和的晕响应。
We present the evolution of the structure of relaxed cold dark matter (CDM) haloes in the cosmology from the Planck satellite. Our simulations cover five decades in halo mass, from dwarf galaxies to galaxy clusters. Because of the increased matter density and power spectrum normalization the concentration-mass relation in the Planck cosmology has a similar to 20 per cent higher normalization at redshift z = 0 compared to Wilkinson Microwave Anisotropy Probe cosmology. We confirm that CDM haloes are better described by the Einasto profile; for example, at scales near galaxy half-light radii CDM haloes have significantly steeper density profiles than implied by Navarro-Frenk-White (NFW) fits. There is a scatter of similar to 0.2 dex in the Einasto shape parameter at fixed halo mass, adding further to the diversity of CDM halo profiles. The evolution of the concentration-mass relation in our simulations is not reproduced by any of the analytic models in the literature. We thus provide a simple fitting formula that accurately describes the evolution between redshifts z = 5 and 0 for both NFW and Einasto fits. Finally, the observed concentrations and halo masses of spiral galaxies, groups and clusters of galaxies at low redshifts are in good agreement with our simulations, suggesting only mild halo response to galaxy formation on these scales.