How cold is dark matter? Constraints from Milky Way satellites
How cold is dark matter? Constraints from Milky Way satellites
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DOI：
10.1111/j.1745-3933.2010.00825.x
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发表时间：
2009-10
影响因子：
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通讯作者：
A. Macciò;Fabio Fontanot Mpia;Heidelberg;Inaf Trieste
中科院分区：
文献类型：
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作者：
A. Macciò;Fabio Fontanot Mpia;Heidelberg;Inaf Trieste
我们测试了银河系卫星的光度函数作为暗物质粒子性质的约束。我们在标准冷暗物质模型和四种暖暗物质 (WDM) 场景中对星系大小的光晕的演化进行了无耗散高分辨率 N 体模拟，并对 WDM 粒子质量 mw 选择了不同。然后，我们将数值模拟的结果与星系形成的半解析模型相结合，以推断卫星群的属性。令人惊讶的是，我们发现即使是具有相对较低MW值（2-5keV）的WDM模型也能够重现观测到的超微弱（Mv < -9）矮星系的丰度，以及观测到的300 pc内的光度和质量之间的关系。我们的结果表明热波分复用的下限为 1 keV，这与之前其他天体物理观测（例如莱曼 α 森林和引力透镜）的结果大致一致。
We test the luminosity function of Milky Way satellites as a constraint for the nature of dark matter particles. We perform dissipationless high-resolution N-body simulations of the evolution of Galaxy-sized halo in the standard cold dark matter model and in four warm dark matter (WDM) scenarios, with a different choice for the WDM particle mass mw. We then combine the results of the numerical simulations with semi-analytic models for galaxy formation, to infer the properties of the satellite population. Quite surprisingly, we find that even WDM models with relatively low mw values (2–5 keV) are able to reproduce the observed abundance of ultra faint (Mv < −9) dwarf galaxies, as well as the observed relation between luminosity and mass within 300 pc. Our results suggest a lower limit of 1 keV for thermal WDM, in broad agreement with previous results from other astrophysical observations such as Lyman α forest and gravitational lensing.