论文标题
Sloan数字天空调查数据版本7和Elucid模拟的Galaxy-Halo尺寸关系
Galaxy-halo size relation from Sloan Digital Sky Survey Data Release 7 and the ELUCID simulation
论文作者
论文摘要
基于Sloan数字天空调查数据中的星系，仅在暗物质中，仅在暗物质中，宇宙学和限制性的耗尽模拟中的暗物质光环，我们研究了与恒星质量$ \ gtrsim 10^{8} h^{8} h^{-2} h^{-2} h {-2} {-2} {\ rmmmmmmm and的中央星系半径之间的关系带有病毒质量$ \ gtrsim的物质光环10^{10.5} h^{ - 1} {\ rm m} _ \ odot $，以及星系 - halo尺寸关系对光环旋转和浓度的依赖性。观察中的星系使用新型的邻里次音丰度匹配方法与Elucid模拟中的暗物质（子）光环匹配。对于银河系2d半光$ r_ {50} $，我们发现早期和晚期星系具有与$ r_ {50} \ propto r _ {\ rm vir}^0.55} $相同的幂律指数0.55，尽管早期的2d radii halo halo halo halo halo halo halo halo halo halo halo halo halo shalo in {\ rm vir}^{0.55} $半径。当将2d半光r_r_ {50} $转换为3D半质量半径$ r_ {1/2} $时，早期和晚期星系都显示出与$ \ log r_ {1/2} = 0.55 \ log（r _} = 0.55 \ r_ {rm rm vir} {\ rm rm vir} {\ rm rm vir} {\ rm rm vir} {\ rm rm vir} KPC}） + 0.39 $。我们发现Galaxy-Halo尺寸比$ r_ {1/2}/ r _ {\ rm vir} $随着晕圈质量的增加而减小。在固定的光晕质量下，银河系升高比对光环自旋或浓度没有显着依赖性。
Based on galaxies in the Sloan Digital Sky Survey Data Release 7 (SDSS DR7) and dark matter haloes in the dark matter only, cosmological and constrained ELUCID simulation, we investigate the relation between the observed radii of central galaxies with stellar mass $\gtrsim 10^{8} h^{-2}{\rm M}_\odot$ and the virial radii of their host dark matter haloes with virial mass $\gtrsim 10^{10.5} h^{-1}{\rm M}_\odot$, and the dependence of galaxy-halo size relation on the halo spin and concentration. Galaxies in observation are matched to dark matter (sub-)haloes in the ELUCID simulation using a novel neighborhood subhalo abundance matching method. For galaxy 2D half-light radii $R_{50}$, we find that early- and late-type galaxies have the same power-law index 0.55 with $R_{50} \propto R_{\rm vir}^{0.55}$, although early-type galaxies have smaller 2D half-light radii than late-type galaxies at fixed halo virial radii. When converting the 2D half-light radii $R_{50}$ to 3D half-mass radii $r_{1/2}$, both early- and late-type galaxies display similar galaxy-halo size relations with $\log r_{1/2} = 0.55 \log (R_{\rm vir}/210 h^{-1}{\rm kpc}) + 0.39$. We find that the galaxy-halo size ratio $r_{1/2}/ R_{\rm vir}$ decreases with increasing halo mass. At fixed halo mass, there is no significant dependence of galaxy-halo size ratio on the halo spin or concentration.
