论文标题
暗物质光环的相空间结构
The Phase Space Structure of Dark Matter Halos
论文作者
论文摘要
暗物质光环的相空间结构可用于测量光环的质量，推断质量吸积率并探测改性重力的影响。先前的研究表明，可以使用密度曲线的斜率在位置空间中测量飞溅半径。使用N体模拟，我们表明暗物质光环的相空间结构不会在此飞溅半径下结束。取而代之的是，存在一个区域，其中插入，飞溅和病毒的光环在空间上混合在一起。我们对三个运动学不同种群的分布进行了建模，并表明存在“边缘半径”，除了暗物质光环没有旋转的子结构。该半径是以前的作品中定义的飞溅半径的固定倍数，可以解释为半径，其中包含暗物质颗粒的伪造物的固定部分。我们的结果为Tomooka等人的伴侣论文中采用的卫星星系模型提供了牢固的理论基础，在那里我们分析了SDSS Redmapper簇的相空间分布。
The phase space structure of dark matter halos can be used to measure the mass of the halo, infer mass accretion rates, and probe the effects of modified gravity. Previous studies showed that the splashback radius can be measured in position space using the slope of the density profile. Using N-body simulations, we show that the phase space structure of the dark matter halo does not end at this splashback radius. Instead, there exists a region where infalling, splashback, and virialized halos are mixed spatially. We model the distribution of the three kinematically distinct populations and show that there exists an "edge radius" beyond which a dark matter halo has no orbiting substructures. This radius is a fixed multiple of the splashback radius as defined in previous works, and can be interpreted as a radius which contains a fixed fraction of the apocenters of dark matter particles. Our results provide a firm theoretical foundation to the satellite galaxy model adopted in the companion paper by Tomooka et al., where we analyzed the phase space distribution of SDSS redMaPPer clusters.
