论文标题
合并期间暗物质尖的扁平：M31的模型
Flattening of dark matter cusps during mergers: model of M31
论文作者
论文摘要
我们运行高分辨率完全GPU N体模拟，以证明M31中的暗物质分布构成了核心样轮廓。丰富的观察数据，尤其是在巨大的恒星流上，对我们的模拟的初始条件提供了严格的约束。我们证明，高度偏心轨道上的卫星积聚会加热M31的中央部分，导致暗物质颗粒的外向迁移，使中央尖质在超过十年的规模上使中央尖锐变平，并产生了一个新的独立于模型的暗物质曲线，该暗物质与核心良好。我们的结果表明，类似核心的中央剖面可能是最初是cuspy但在几乎径向轨道上积聚卫星的大型星系的常见特征。
We run high resolution fully GPU N-body simulations to demonstrate that the dark matter distribution in M31 is well-fitted by a core-like profile. Rich observational data especially on the giant stellar stream provides stringent constraints on the initial conditions of our simulations. We demonstrate that accretion of a satellite on a highly eccentric orbit heats up the central parts of M31, causes an outward migration of dark matter particles, flattens the central cusp over more than a decade in scale and generates a new model-independent dark matter profile that is well-fitted by a core. Our results imply that core-like central profiles could be a common feature of massive galaxies that have been initially cuspy but have accreted satellites on nearly radial orbits.
