论文标题
ARTEMIS模拟中积聚的恒星运动学与暗物质旋转之间的相关性
A correlation between accreted stellar kinematics and dark matter halo spin in the ARTEMIS simulations
论文作者
论文摘要
我们报告了gaia-sausage-cenceladus（GSE）类似物的存在与暗物质旋转中的gaia-sausausage-enceladus（GSE）类似物之间的相关性。在高度径向轨道上包含大量积聚的恒星（如GSE）的光环平均比具有更多各向同性恒星速度分布的对应物较低。中值修改的旋转参数$λ^\ prime $在当今的$ \ sim1.7 $中不同，当远离病毒平衡的光环时，其值相似。我们还表明，积聚的恒星占包含GSE类似物的光环中的恒星种群的较小比例，并从具有恒星质量的卫星中剥离，通常小于$ \ sim4 $ $倍。我们的发现表明，具有类似GSE的功能的DM光环的较高自旋归因于具有恒星质量$ \ sim10^{10} m_ \ odot $的合并，这不会导致像GSE这样的径向径向径向的各向异性特征。
We report a correlation between the presence of a Gaia-Sausage-Enceladus (GSE) analogue and dark matter halo spin in the ARTEMIS simulations of Milky Way-like galaxies. The haloes which contain a large population of accreted stars on highly radial orbits (like the GSE) have lower spin on average than their counterparts with more isotropic stellar velocity distributions. The median modified spin parameters $λ^\prime$ differ by a factor of $\sim1.7$ at the present-day, with a similar value when the haloes far from virial equilibrium are removed. We also show that accreted stars make up a smaller proportion of the stellar populations in haloes containing a GSE analogue, and are stripped from satellites with stellar masses typically $\sim4$ times smaller. Our findings suggest that the higher spin of DM haloes without a GSE-like feature is due to mergers with large satellites of stellar mass $\sim10^{10}M_\odot$, which do not result in prominent radially anisotropic features like the GSE.
