The patch like model of the hierarchical galaxy formation in the $Λ$CDM cosmological model with small damping scale is considered. In this model galaxies and clusters of galaxies are identified with rare high density peaks, what suppresses the action of random factors in the vicinity of peaks and makes the process of halos formation more rapid and regular. High concentration of irregular subhalos surrounding the central peaks and their subsequent merging just after formation allows to consider this medium as a mixture of collisionless dispersed dark matter (DM) particles and collisional subhalos. Merging of these subhalos with the central dominating halo is accompanied by tidal destruction of the central cusp, what progressively shallows the density profile and promotes formation of super massive central black holes. In the framework of this model we can reproduce the observed correlation of mass and density of virialized galaxies and clusters of galaxies known as the virial paradox [4,5]. These correlations are closely linked with the composition of DM and the shape of the power spectrum what allows to restrict them using already available observations. These correlations put constraints on the HDM and WDM models and allow to test models of cosmological inflation. We confirm that the missing satellite problem is directly linked with the virial paradox and reheating of the Universe which increases temperature and entropy of the baryons, prevents formation of first stars and divides halos into two populations: the first one includes galaxies formed before reheating which are mainly concentrated in the vicinity of the massive ones while the second population -- numerous dark halos formed after reheating -- accumulates majority of DM but does not contain stars. Their spatial distribution is more homogeneous.
Role of prompt cusps in driving the core collapse of SIDM halos
Massachusetts Institute of Technology（麻省理工学院）；University of Chicago（芝加哥大学）；Carnegie Observatories（卡内基观测站）；Center for Astrophysics, Harvard & Smithsonian（哈佛-史密森天体物理中心）；Rice University（莱斯大学）
NIHAO-XXIII: Dark Matter density shaped by Black Hole feedback
我们提出了一个系统的分析反应的暗物质分布到星系形成跨越超过八个数量级的恒星质量。我们扩展了NIHAO-IV论文（Tollet等人）中提出的先前工作。通过增加46个新的高分辨率模拟的大质量星系进行列入黑洞反馈。我们表明，外流产生的活动星系核能够部分抵消暗物质收缩，由于大型中央恒星组成的大规模晕。净效应是放松的中央暗物质分布，移动到一个不太尖的密度分布在晕质量大于$\approx 3 \times 10^{12}$ M $_{\odot}$。密度剖面斜率平均值（$α$）周围的散射是相当恒定的（$Δα\approx 0.3$），除了在$10^{12}$ M $_{\odot}$周围有晕质量的星系，在从恒星到活动星系核反馈主导系统的过渡中，散射几乎增加了三倍。我们提供了有用的拟合公式的斜率的暗物质密度剖面的维里半径的百分之几为整个恒星质量范围：$10^5-10^{12}$ M $_{\odot}$（$2 \times 10^9-5 \times 10^{13}$ M $_{\odot}$晕质量）。
Supermassive Black Hole Formation at High Redshifts via Direct Collapse: Physical Processes in the Early Stage
我们使用数值模拟来探索是否直接崩溃可以导致形成SMBH种子在高Z。我们跟踪了2 x 10^8 Mo和1 kpc的DM晕内气体的演化。我们采用宇宙学密度剖面和j分布。我们的目标是了解塌陷流如何克服离心障碍，以及它是否会受到破碎。我们发现，崩溃导致一个中心的失控或偏离中心的碎片。在离心屏障内部形成盘状构造。对于更尖的DM分布，气体塌陷更多，并经历棒状扰动和中心失控。我们已经跟踪了这一流入量，下降到约10^{-4} pc。流动保持等温，特定的角动量是有效地转移的重力扭矩在级联的嵌套酒吧。这种级联支持自相似的圆盘状坍缩。在坍缩阶段，维里超音速湍流发展和破碎阻尼。对于较大的初始DM核心，时间尺度变得更长。在具有更有组织的初始旋转的模型中，环面形成并似乎由湍流运动支撑。演化取决于两个时间尺度之间的竞争，对应于中心失控和偏离中心的碎片化的开始。对于较少组织的旋转，环面被大大削弱，中央吸积时间尺度缩短，偏离中心的碎片被抑制-触发中央失控，即使在以前的“稳定”模型。由此得到的SMBH质量在2 x 10^4 Mo - 2 x 10^6 Mo之间，远高于第III星族残留物。我们认为，上述上限似乎是更现实的质量。该模型的推论包括SMBH和DM晕质量之间可能的相关性，以及SMBH和晕质量函数之间的相似性，在形成时。
