The galaxy mass-size relation in CARLA clusters and proto-clusters at 1.4 < z < 2.8: Larger cluster galaxy sizes
The galaxy mass-size relation in CARLA clusters and proto-clusters at 1.4 < z < 2.8: Larger cluster galaxy sizes
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1.4 < z < 2.8 时 CARLA 星团和原星团中的星系质量-大小关系：较大的星团星系大小
DOI：
10.1051/0004-6361/202244634
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发表时间：
2023
影响因子：
6.5
通讯作者：
Afanasiev A
中科院分区：
文献类型：
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作者：
Afanasiev A
我们研究了 CARLA 巡天中 15 个经光谱证实的 1.4 <z< 2.8 星团中的星系质量与大小关系。我们的星团跨越了该范围内的总恒星质量（晕轮质量大约在该范围内）。我们的主要发现是，质量 log(M/M⊙) > 10.5 的无源早期型星系团 (ETG) atz≳ 1.5 系统地比 CANDELS 巡天中具有相似红移和质量的场 ETG 大 ≳0.2 − 0.3dex (≳3σ)。与现场相比，带有红移的被动 ETG 平均尺寸演化速度较慢，为 1 <z< 2。正如模型所预测的那样，这可以通过不同质量晕中的星系形成和早期演化的早期差异来解释。不排除其他物理机制，例如场星系中的强压实和气体耗散，以及随后的一系列合并，也可能在场ETG演化中发挥了重要作用，但不一定在星团星系的演化中发挥了重要作用。我们的被动 ETG 质量-尺寸关系显示出在 9.6 < log(M/M⊙) < 10.5 处趋于平坦的趋势，其中平均尺寸为 log(Re/kpc) = 0.05 ± 0.22，这与现场和本地宇宙中的星系尺寸大致一致。这意味着质量-尺寸关系低端的星系从z∼ 2到现在并没有演化太多，并且它们的尺寸在星团和场中以类似的方式演化。最亮的星团星系与卫星具有相同的质量-大小关系，这表明它们的大小演化与红移z≳ 2处的卫星没有什么不同。一半的活跃早期型星系（占我们ETG样本的30%）遵循场被动星系质量-大小关系，另一半遵循场活跃星系质量-大小关系。这些星系很可能经历了最近的合并或邻近星系的相互作用，并且很可能会在稍后的时期淬灭并增加星团中被动 ETG 的比例。我们没有观察到大量致密星系（只有一个），正如在这些红移的现场观察到的那样，这意味着我们星团中的星系在接近其致密的时期没有被观察到。
We study the galaxy mass-size relation in 15 spectroscopically confirmed clusters at 1.4 <z< 2.8 from the CARLA survey. Our clusters span a total stellar mass in the range (with an approximate halo mass in the range ). Our main finding is that cluster passive early-type galaxies (ETGs) atz≳ 1.5 with a mass log(M/M⊙) > 10.5 are systematically ≳0.2 − 0.3dex larger (≳3σ) than field ETGs at a similar redshift and mass from the CANDELS survey. The passive ETG average size evolution with redshift is slower at 1 <z< 2 when compared to the field. This could be explained by early-epoch differences in the formation and early evolution of galaxies in haloes of a different mass, as predicted by models. It does not exclude that other physical mechanisms, such as strong compaction and gas dissipation in field galaxies, followed by a sequence of mergers may have also played a significant role in the field ETG evolution, but not necessarily in the evolution of cluster galaxies. Our passive ETG mass-size relation shows a tendency to flatten at 9.6 < log(M/M⊙) < 10.5, where the average size is log(Re/kpc) = 0.05 ± 0.22, which is broadly consistent with galaxy sizes in the field and in the local Universe. This implies that galaxies in the low end of the mass-size relation do not evolve much fromz∼ 2 to the present, and that their sizes evolve in a similar way in clusters and in the field. Brightest cluster galaxies lie on the same mass-size relation as satellites, suggesting that their size evolution is not different from satellites at redshiftz≳ 2. Half of the active early-type galaxies, which are 30% of our ETG sample, follow the field passive galaxy mass-size relation, and the other half follow the field active galaxy mass-size relation. These galaxies likely went through a recent merger or neighbor galaxy interaction, and would most probably quench at a later epoch and increase the fraction of passive ETGs in clusters. We do not observe a large population of compact galaxies (only one), as is observed in the field at these redshifts, implying that the galaxies in our clusters are not observed in an epoch close to their compaction.