论文标题
银河系卫星的大型自我互动的暗物质横截面的动机
Motivations for a Large Self-Interacting Dark Matter Cross Section from Milky Way Satellites
论文作者
论文摘要
我们使用高分辨率缩放N-Body模拟探索了自相互作用的暗物质模型中的银河系Subhalos的性质。我们包括与银河系相匹配的重型磁盘和凸起的重力潜力，这对于获得准确的预测至关重要。在1和5 cm $^2 $ g $^{ - 1} $型号中，Subhalos在主机光环中的预测数量和分布相似，并且他们同意对银河系卫星星系的观察，仅当Subhalos在所有时间> 4.5 km/s的峰值圆形速度峰值时才能够形成银河系。我们在Subhalos的候选物分布中找不到独特的特征，可以帮助区分模型。使用分析模型扩展仿真结果，我们能够证明，在1到5 cm $^2 $^2 $ g $^{ - 1} $之间的subhalos不足以匹配以乳白色方式匹配的浓密和古典矮人球形星系。这激发了速度依赖性的横截面，其值大于5 cm $^2 $ g $^{ - 1} $在与卫星相关的速度下，因此核心崩溃会发生在某些超级和古典矮人的矮小球体中。
We explore the properties of Milky Way subhalos in self-interacting dark matter models for moderate cross sections of 1 to 5 cm$^2$g$^{-1}$ using high-resolution zoom-in N-body simulations. We include the gravitational potential of a baryonic disk and bulge matched to the Milky Way, which is critical for getting accurate predictions. The predicted number and distribution of subhalos within the host halo are similar for 1 and 5 cm$^2$g$^{-1}$ models, and they agree with observations of Milky Way satellite galaxies only if subhalos with peak circular velocity over all time > 4.5 km/s are able to form galaxies. We do not find distinctive signatures in the pericenter distribution of the subhalos that could help distinguish the models. Using an analytic model to extend the simulation results, we are able to show that subhalos in models with cross sections between 1 and 5 cm$^2$g$^{-1}$ are not dense enough to match the densest ultra-faint and classical dwarf spheroidal galaxies in the Milky Way. This motivates velocity-dependent cross sections with values larger than 5 cm$^2$g$^{-1}$ at the velocities relevant for the satellites such that core collapse would occur in some of the ultra-faint and classical dwarf spheroidals.
