The stellar mass function of quiescent galaxies in 2 < z < 2.5 protoclusters
The stellar mass function of quiescent galaxies in 2 < z < 2.5 protoclusters
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2 < z < 2.5 原星系团中静止星系的恒星质量函数
DOI：
10.1093/mnras/stad3751
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发表时间：
2023
影响因子：
4.8
通讯作者：
Vulcani, Benedetta
中科院分区：
文献类型：
--
作者：
Edward, Adit H.;Balogh, Michael L.;Bahé, Yannick M.;Cooper, M. C.;Hatch, Nina A.;Marchioni, Justin;Muzzin, Adam;Noble, Allison;Rudnick, Gregory H.;Vulcani, Benedetta
本文分析了COSMOS场中14个已知的2.0 <z< 2.5的原星系团的星系恒星质量函数（SMF），其质量下限为109.5M Ω。我们使用现有的光度红移与统计背景扣除，并考虑恒星形成和静止星系分别从（NUV−r）和（r−J）的颜色。我们的基准样本包括星系团中心1百万秒差距内的星系。恒星形成星系的原星系团SMF的形状在这个红移处与一般场的形状是无法区分的。然而，静止星系的SMF比在磁场中更平坦，在低质量时向上翻转，尽管这只在σ 2σ处有意义。没有强有力的证据表明，在任何质量下，静止星系都占主导地位，对于logM*/M *< 10.5的星系，在1σ置信度下，其比例<15%。我们将我们的结果与1 <z< 1.5的星系群样本进行了比较，并证明了在这些时期之间必须发生大量的环境淬灭，使高质量（）静止星系的相对丰度增加了1.2倍。然而，我们发现，在较低的质量（），不需要额外的环境淬火。
We present an analysis of the galaxy stellar mass function (SMF) of 14 known protoclusters between 2.0 <z< 2.5 in the COSMOS field, down to a mass limit of 109.5M⊙. We use existing photometric redshifts with a statistical background subtraction, and consider star-forming and quiescent galaxies identified from (NUV−r) and (r−J) colours separately. Our fiducial sample includes galaxies within 1 Mpc of the cluster centres. The shape of the protocluster SMF of star-forming galaxies is indistinguishable from that of the general field at this redshift. Quiescent galaxies, however, show a flatter SMF than in the field, with an upturn at low mass, though this is only significant at ∼2σ. There is no strong evidence for a dominant population of quiescent galaxies at any mass, with a fraction <15 per cent at 1σ confidence for galaxies with logM*/M⊙< 10.5. We compare our results with a sample of galaxy groups at 1 <z< 1.5, and demonstrate that a significant amount of environmental quenching must take place between these epochs, increasing the relative abundance of high-mass () quiescent galaxies by a factor ≳ 2. However, we find that at lower masses (), no additional environmental quenching is required.