论文标题
Illustristng快照，用于10 Gyr的最明亮集群星系的动态演变及其宿主群集
IllustrisTNG Snapshots for 10 Gyr of Dynamical Evolution of Brightest Cluster Galaxies and Their Host Clusters
论文作者
论文摘要
我们根据Illainistng-300仿真探索了$ z <2 $的大量簇及其最亮集星系（BCG）的动力学特性的红移演变。我们选择270个大型簇，用$ m_ {200} <10^{14}〜{\ rm m} _ {\ odot} $ at $ z = 0 $，并根据合并树追踪其祖细胞。从覆盖$ z <2 $的67个红移快照中，我们将3D subhalo速度分散量计算为群集速度分散（$σ_{\ rm cl} $）。我们还计算BCGS的3D恒星速度分散（$σ_{\ rm *，〜bcg} $）。 $σ_ {\ rm cl} $和$σ_ {\ rm *，〜bcg} $随着宇宙年龄的增长而增加。 BCG速度分散剂的增长速度比簇速度分散率更慢。此外，BCG速度色散的红移演化显示出与相邻星系的动态相互作用（主要合并）导致的一些红移变化。我们表明，$σ_{\ rm *，〜bcg} $与$σ_ {\ rm cl} $ at $ z> 1 $相媲美，提供了一个有趣的观察测试。 $σ_ {\ rm cl} $和$σ_ {\ rm *，〜bcg} $的模拟红移演变普遍与观察到的群集样本符合$ z <0.3 $，但散布较大。未来的大型光谱调查达到高红移将测试模拟对簇及其BCG的质量演化的含义。
We explore the redshift evolution of the dynamical properties of massive clusters and their brightest cluster galaxies (BCGs) at $z < 2$ based on the IllustrisTNG-300 simulation. We select 270 massive clusters with $M_{200} < 10^{14}~{\rm M}_{\odot}$ at $z = 0$ and trace their progenitors based on merger trees. From 67 redshift snapshots covering $z < 2$, we compute the 3D subhalo velocity dispersion as a cluster velocity dispersion ($σ_{\rm cl}$). We also calculate the 3D stellar velocity dispersion of the BCGs ($σ_{\rm *,~BCG}$). Both $σ_{\rm cl}$ and $σ_{\rm *,~BCG}$ increase as universe ages. The BCG velocity dispersion grows more slowly than the cluster velocity dispersion. Furthermore, the redshift evolution of the BCG velocity dispersion shows dramatic changes at some redshifts resulting from dynamical interaction with neighboring galaxies (major mergers). We show that $σ_{\rm *,~BCG}$ is comparable with $σ_{\rm cl}$ at $z > 1$, offering an interesting observational test. The simulated redshift evolution of $σ_{\rm cl}$ and $σ_{\rm *,~BCG}$ generally agrees with an observed cluster sample for $z < 0.3$, but with large scatter. Future large spectroscopic surveys reaching to high redshift will test the implications of the simulations for the mass evolution of both clusters and their BCGs.
