自相互作用暗物质（SIDM）是冷暗物质（CDM）的一种碰撞形式，最初被提出来解决当结构形成的无碰撞CDM理论与小尺度星系的观测进行比较时出现的问题。所提出的弹性碰撞对结构形成的定量影响已经估计以前的Monte Carlo N-体模拟和导电流体模型，明显分歧的结果。为了改善这种情况，我们直接比较新的Monte Carlo N-体模拟和解决方案的导电流体模型，孤立的SIDM晕的固定质量。这使我们能够清楚地将重力热弛豫的影响与膨胀背景宇宙中连续质量吸积的影响分开。当这两种方法以前被应用于晕形成与宇宙学边界条件，他们不同意的数量级的散射截面的大小需要解决所谓的“尖核问题。“然而，我们在这里表明，对于孤立的晕，这些方法在20%以内相互一致。这表明这两种方法是一致的，它们对宇宙学晕的分歧并不是由于它们的有效性被打破。这里研究的孤立晕经历重力热塌缩。我们比较了这两种方法计算的解决方案重力热坍塌从几个初始条件。这使我们能够校准热传导，其中考虑到流体模型中弹性硬球散射的影响。然而，要使这两种方法在孤立晕上接近一致，所需的热导率参数的调整量太小，无法解释以前在宇宙学背景下发现的差异。
英文摘要：
Self-Interacting Dark Matter (SIDM) is a collisional form of cold dark matter (CDM), originally proposed to solve problems that arose when the collisionless CDM theory of structure formation was compared with observations of galaxies on small scales. The quantitative impact of the proposed elastic collisions on structure formation has been estimated previously by Monte Carlo N-body simulations and by a conducting fluid model, with apparently diverging results. To improve this situation, we make direct comparisons between new Monte Carlo N-body simulations and solutions of the conducting fluid model, for isolated SIDM haloes of fixed mass. This allows us to separate cleanly the effects of gravothermal relaxation from those of continuous mass accretion in an expanding background universe. When these two methods were previously applied to halo formation with cosmological boundary conditions, they disagreed by an order of magnitude about the size of the scattering cross section required to solve the so-called 'cusp-core problem.' We show here, however, that the methods agree with each other within 20 per cent for isolated haloes. This suggests that the two methods are consistent, and that their disagreement for cosmological haloes is not caused by a breakdown of their validity.
The isolated haloes studied here undergo gravothermal collapse. We compare the solutions calculated by these two methods for gravothermal collapse starting from several initial conditions. This allows us to calibrate the heat conduction which accounts for the effect of elastic hard-sphere scattering in the fluid model. The amount of tuning of the thermal conductivity parameters required to bring the two methods into close agreement for isolated haloes, however, is too small to explain the discrepancy found previously in the cosmological context.
Gravitational-Wave Image Multiplicity as a Topological Probe of Dark-Matter Core Collapse
School of Physics and Optoelectronic Engineering, Yangtze University（长江大学物理与光电工程学院）；School of Physics and Technology, Wuhan University（武汉大学物理科学与技术学院）；National Centre for Nuclear Research（国家核研究中心）；Department of Basic Courses, Beijing University of Agriculture（北京农学院基础课部）
The diverse dark matter density at sub-kiloparsec scales in Milky Way satellites:implications for the nature of dark matter
银河系（MW）卫星居住在暗物质（DM）的subhalos与广泛的分布的圆形速度剖面。这种多样性随着超微弱卫星的加入而增强，这些卫星似乎具有非常高的DM密度，尽管具有很大的系统不确定性。我们认为，如果得到证实，这种大的MW卫星人口的多样性构成了一个严重的考验，DM性质的结构形成理论与可能的影响。对于冷暗物质模型，多样性可能是由MW盘和强超新星反馈引起的晕下潮汐破坏的综合效应的特征。对于功率谱中具有矮尺度截止的模型，多样性是矮尺度晕丰度较低的结果。这种多样性是最具挑战性的自相互作用暗物质（SIDM）模型的横截面$σ/m_χ\gtrsim1~$ cm $^2$ g $^{-1}$的subhalos有太低的密度来解释超微弱的星系。我们提出了一个新的解决方案来解释MW卫星的多样性的基础上重力热塌陷的SIDM晕。这种解决方案需要一个速度依赖的截面，预测双峰分布的尖形密集（崩溃）subhaloes符合超微弱的卫星，和核心的低密度subhaloes符合较亮的卫星。
The host halo masses of AGNs and quasars at $z \sim 3-7$ with TNG-Cluster, FLAMINGO and other cosmological galaxy simulations
Max-Planck-Institut für Astronomie（马克斯·普朗克天文学研究所）；Universität Heidelberg, Zentrum für Astronomie, ITA（海德堡大学天文中心）；Universität Heidelberg, Interdisziplinäres Zentrum für Wissenschaftliches Rechnen（海德堡大学跨学科科学计算中心）；Leiden Observatory, Leiden University（莱顿天文台，莱顿大学）；INAF — Osservatorio di Astrofisica e Scienza dello Spazio（意大利国家天体物理研究所空间天体物理与科学观测站）
