论文标题
在边缘：银河系质量星系的恒星和暗物质光环之间的关系
On the Edge: the relation between stellar and dark matter haloes of Milky Way-mass galaxies
论文作者
论文摘要
我们研究了宇宙流体动力学模拟使徒套件中银河系状星系的积聚和暗物质光环的积累。我们表明，恒星光环主要由少数大型矮人剥离的恒星组成，其中大多数被当天破坏了。另一方面，暗物质光环主要由小的未解决的亚乳子（$ \ lyssim 10^6 $ m $ _ {\ odot} $）和一个由从未绑定到Subhalo的粒子组成的``平滑''组件组成。尽管存在这些差异，但构成大多数恒星光环的大型矮人也贡献了很大一部分暗物质。从这些矮人中剥离的恒星和暗物质是通过它们的运动学相关的，这在光环的相空间结构中留下了烙印。我们检查了特征位置（例如苛性剂）在恒星的相空间与深色光环特性之间的关系。我们表明，恒星光环的``边缘''是暗物质光环质量和组装历史的探测。银河系质量星系的边缘应在31-36 mag arcsec $^{ - 2} $的表面亮度下可见。
We investigate the build-up of the accreted stellar and dark matter haloes of Milky Way-like galaxies in APOSTLE suite of cosmological hydrodynamics simulations. We show that the stellar halo is made up primarily of stars stripped from a small number of massive dwarfs, most of which are disrupted by the present day. The dark matter halo, on the other hand, is made up primarily of small unresolved subhaloes ($\lesssim 10^6$ M$_{\odot}$) and a ``smooth'' component consisting of particles which were never bound to a subhalo. Despite these differences, the massive dwarfs that make up the majority of the stellar halo also contribute a significant fraction of the dark matter. The stars and dark matter stripped from these dwarfs are related through their kinematics and this leaves imprints in the phase-space structure of the haloes. We examine the relation between the location of features, such as caustics, in the phase space of the stars and dark halo properties. We show that the ``edge'' of the stellar halo is a probe of dark matter halo mass and assembly history. The edges of Milky Way-mass galaxies should be visible at a surface brightness of 31-36 mag arcsec$^{-2}$.
