A statistical semi-empirical model: satellite galaxies in groups and clusters
A statistical semi-empirical model: satellite galaxies in groups and clusters
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DOI：
10.1093/mnras/sty3281
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发表时间：
2018-11
影响因子：
4.8
通讯作者：
P. Grylls;F. Shankar;L. Zanisi;M. B. U. O. Southampton;U. Pennsylvania
中科院分区：
文献类型：
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作者：
P. Grylls;F. Shankar;L. Zanisi;M. B. U. O. Southampton;U. Pennsylvania
我们提出了一个统计的卫星经验模型STEEL，用来探测卫星星系在星系团和星系团中的分布。我们的快速统计方法依赖于追踪中央和卫星晕的丰度，通过它们的质量函数在所有宇宙时代，几乎没有限制的宇宙体积和质量分辨率。从平均晕吸积的历史和subhalo质量函数，卫星的质量函数逐步建立在时间上通过丰度匹配技术的中心在本地宇宙的数量密度的约束。通过执行动态合并的时间尺度预测的高分辨率N体模拟，我们得到的卫星分布的恒星质量和晕质量的函数与当前的数据一致。我们表明，恒星剥离、星星形成和猝灭在将大质量卫星的数密度设置为M * 3× 1010 M ⊙以上方面都发挥着次要作用。我们进一步表明，在我们的经验模型中使用的观测到的星星形成率超过了预测低于M 3× 1010 M的低质量卫星，而来自连续性方程方法的星星形成率产生了正确的丰度类似于以前的结果的中心。
We present STEEL, a STatistical sEmi-Empirical modeL, designed to probe the distribution of satellite galaxies in groups and clusters. Our fast statistical methodology relies on tracing the abundances of central and satellite haloes via their mass functions at all cosmic epochs with virtually no limitation on cosmic volume and mass resolution. From mean halo accretion histories and subhalo mass functions, the satellite mass function is progressively built in time via abundance matching techniques constrained by number densities of centrals in the local Universe. By enforcing dynamical merging time-scales as predicted by high-resolution N-body simulations, we obtain satellite distributions as a function of stellar mass and halo mass consistent with current data. We show that stellar stripping, star formation, and quenching play all a secondary role in setting the number densities of massive satellites above M∗≳3×1010M⊙. We further show that observed star formation rates used in our empirical model over predict low-mass satellites below M∗≲3×1010M⊙, whereas star formation rates derived from a continuity equation approach yield the correct abundances similar to previous results for centrals.