The First Billion Years project: dark matter haloes going from contraction to expansion and back again
The First Billion Years project: dark matter haloes going from contraction to expansion and back again
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第一个十亿年项目：暗物质晕从收缩到扩张再回来
DOI：
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发表时间：
2013
期刊：
影响因子：
--
通讯作者：
C. D. Vecchia
中科院分区：
文献类型：
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作者：
Andrew J. Davis;S. Khochfar;C. D. Vecchia
我们研究了重子对第一个星系内部暗物质轮廓的影响，使用第一个十亿年的模拟z=16-6之间的长期演化集。使用一个大的统计样本从两个模拟相同的体积和宇宙学的初始条件，一个有和一个没有重子，我们能够直接比较晕与他们的重子免费同行，允许修改的详细研究暗物质密度分布由于重子的存在在星系形成的第一个十亿年。对于我们样本中约5000个晕中的每一个，我们使用eta量化重子的影响，eta定义为重子运行中100 pc中封闭的暗物质质量与没有重子的对应物的比值。在这个时代的星系的快速增长，我们发现，这些第一个星系的许多晕显示出增强的暗物质在晕中心相比，重子自由模拟，而许多其他显示赤字。我们发现η的平均值接近于1，但存在较大的分散性，标准差为0.677。这种增强在时间上是周期性的，并跟踪星系的星星形成周期;当气体福尔斯落到中心并形成恒星时，暗物质也会移动进来。超新星的反馈会带走气体，暗物质会再次对变化的电势做出反应。我们研究了三种与重子运动和暗物质运动相关的物理模型：绝热收缩、动力学摩擦和快速外流。摘要，完整摘要见正文
We study the effect of baryons on the inner dark matter profile of the first galaxies using the First Billion Years simulation between z=16-6 before secular evolution sets in. Using a large statistical sample from two simulations of the same volume and cosmological initial conditions, one with and one without baryons, we are able to directly compare haloes with their baryon-free counterparts, allowing a detailed study of the modifications to the dark matter density profile due to the presence of baryons during the first billion years of galaxy formation. For each of the ~ 5000 haloes in our sample we quantify the impact of the baryons using eta, defined as the ratio of dark matter mass enclosed in 100 pc in the baryonic run to its counterpart without baryons. During this epoch of rapid growth of galaxies, we find that many haloes of these first galaxies show an enhancement of dark matter in the halo centre compared to the baryon-free simulation, while many others show a deficit. We find that the mean value of eta is close to unity, but there is a large dispersion, with a standard deviation of 0.677. The enhancement is cyclical in time and tracks the star formation cycle of the galaxy; as gas falls to the centre and forms stars, the dark matter moves in as well. Supernova feedback then removes the gas, and the dark matter again responds to the changing potential. We study three physical models relating the motion of baryons to that of the dark matter: adiabatic contraction, dynamical friction, and rapid outflows. Abridged, see text for full abstract
DOI：
10.1111/j.1365-2966.2009.15034.x
发表时间：
2008-08
影响因子：
4.8
作者：
K. Dolag;S. Borgani;S. Borgani;S. Borgani;G. Murante;V. Springel
通讯作者：
K. Dolag;S. Borgani;S. Borgani;S. Borgani;G. Murante;V. Springel
影响因子：
8.7
作者：
Komatsu, E.;Smith, K. M.;Wright, E. L.
通讯作者：
Wright, E. L.