Redefining the Missing Satellites Problem
Redefining the Missing Satellites Problem
复制标题
重新定义卫星失踪问题
DOI：
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发表时间：
2007
期刊：
影响因子：
--
通讯作者：
P. Madau
中科院分区：
文献类型：
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作者：
L. Strigari;J. Bullock;M. Kaplinghat;J. Diemand;M. Kuhlen;P. Madau
银河系大小的冷暗物质（CDM）晕的数值模拟预测了小暗物质亚晕的质量函数急剧上升和亚结构数量大大超过观测到的银河系卫星。目前已有几种解释，但由于卫星晕的最大圆速度（Vmax）没有得到很好的约束，这就妨碍了理论与观测之间的详细比较。我们提出了著名的银河系矮卫星的综合质量模型，并推导出似然函数，表明它们的质量在0.6 kpc （M0.6）以内受到现有数据的强烈约束。我们显示明亮的卫星晕的M0.6质量函数在~107和108 M☉之间是平坦的。我们使用“Via Lactea”n体模拟表明，CDM亚晕的M0.6质量函数在此范围内急剧上升。我们排除了这样一种假设，即银河系的11颗众所周知的卫星是由11个最大的亚晕所承载的。我们表明，最亮的卫星对应最早形成的亚晕或最大质量的吸积物体的模型都再现了观测到的质量函数。对新发现的矮卫星进行类似的分析将进一步测试这些情景，并为CDM小尺度功率谱和暖暗物质模型提供强有力的约束。
Numerical simulations of Milky Way-size cold dark matter (CDM) halos predict a steeply rising mass function of small dark matter subhalos and a substructure count that greatly outnumbers the observed satellites of the Milky Way. Several proposed explanations exist, but detailed comparison between theory and observation in terms of the maximum circular velocity (Vmax) of the subhalos is hampered by the fact that Vmax for satellite halos is poorly constrained. We present comprehensive mass models for the well-known Milky Way dwarf satellites and derive likelihood functions to show that their masses within 0.6 kpc (M0.6) are strongly constrained by the present data. We show that the M0.6 mass function of luminous satellite halos is flat between ~107 and 108 M☉. We use the "Via Lactea" N-body simulation to show that the M0.6 mass function of CDM subhalos is steeply rising over this range. We rule out the hypothesis that the 11 well-known satellites of the Milky Way are hosted by the 11 most massive subhalos. We show that models where the brightest satellites correspond to the earliest forming subhalos or the most massive accreted objects both reproduce the observed mass function. A similar analysis with the newly discovered dwarf satellites will further test these scenarios and provide powerful constraints on the CDM small-scale power spectrum and warm dark matter models.
影响因子：
7.8
作者：
Lukewich MK;Rogers RC;Lomax AE
通讯作者：
Lomax AE