An environment-dependent halo mass function as a driver for the early quenching of z = 1.5 cluster galaxies
An environment-dependent halo mass function as a driver for the early quenching of z = 1.5 cluster galaxies
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依赖于环境的晕质量函数作为 z = 1.5 星团星系早期猝灭的驱动因素
DOI：
10.1093/mnras/stae341
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发表时间：
2024
影响因子：
4.8
通讯作者：
Ahad S
中科院分区：
文献类型：
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作者：
Ahad S
许多具有恒星质量 (M⋆) 的 1.5 个星系已经在星系团 (>50%) 和场 (>20%) 中淬灭，与场相比，星系团在所有恒星质量下都具有更高的淬灭分数。一个令人费解的问题是，这些巨大的猝灭星系在星团和场中都有相似年龄的恒星群。这表明，尽管星团中的淬灭分数较高，但大质量星系的主要淬灭机制在两种环境中是相似的。在这项工作中，我们使用来自宇宙流体动力学模拟 Hydrangea 和 EAGLE 的数据来测试 z=1.5 星团中大质量星系的过量淬火部分是否是由于其晕特性与场相比的根本差异造成的。我们发现，(i) 对于具有较高暗物质晕峰值最大圆周速度（vmax, 峰值）的星系，1.5<z<3.5 处的淬火分数始终较高，并且 (ii) 与场中心相比，vmax, 峰值的分布强烈偏向于星团卫星的更高值。由于星团和场星系的光晕特性存在这种差异，长期过程本身就可以解释高红移（原）星团中大质量猝灭星系的（大部分）环境过剩。从表面上看，我们的结果挑战了流行的猝灭模型的基本假设，即星团是由坠落场星系的无偏子集组装而成的。如果得到证实，这将意味着此类模型必然会在高红移情况下失败，正如最近的观察所表明的那样。
Manyz≈1.5 galaxies with a stellar mass (M⋆)are already quenched in both galaxy clusters (>50 per cent) and the field (>20 per cent), with clusters having a higher quenched fraction at all stellar masses compared to the field. A puzzling issue is that these massive quenched galaxies have stellar populations of similar age in both clusters and the field. This suggests that, despite the higher quenched fraction in clusters, the dominant quenching mechanism for massive galaxies is similar in both environments. In this work, we use data from the cosmological hydrodynamic simulations Hydrangea and EAGLE to test whether the excess quenched fraction of massive galaxies inz=1.5 clusters results from fundamental differences in their halo properties compared to the field. We find that (i) at, quenched fractions at 1.5<z<3.5 are consistently higher for galaxies with higher peak maximum circular velocity of the dark matter halo (vmax, peak), and (ii) the distribution ofvmax, peakis strongly biased towards higher values for cluster satellites compared to the field centrals. Due to this difference in the halo properties of cluster and field galaxies, secular processes alone may account for (most of) the environmental excess of massive quenched galaxies in high-redshift (proto-)clusters. Taken at face value, our results challenge a fundamental assumption of popular quenching models that clusters are assembled from an unbiased subset of infalling field galaxies. If confirmed, this would imply that such models must necessarily fail at high redshift, as indicated by recent observations.