AI 中文总结
研究詹姆斯·韦布空间望远镜/近红外相机选择的高红移大质量星系，通过模拟评估观测光度学选择可靠性，构建改进选择，研究星系后代演化，发现当前选择未能识别最庞大高红移星系，警示不宜将其视为红移为0时最庞大星系的直接前身。
AI 中文摘要
早期詹姆斯·韦布空间望远镜/近红外相机的观测揭示了一批令人困惑的高红移大质量星系候选体，此前的静止帧紫外观测中基本没有。光谱后续观测对这些候选体既有确认也有质疑，其潜在的数量过多可能挑战传统星系形成模型。本研究通过将用于识别观测数据中这些候选体的光度学选择应用于TNG300模拟中的星系，并采用合成尘埃消光光度学来评估其可靠性。在所考虑的五个观测选择标准中，发现佩雷斯 - 冈萨雷斯等人提出的选择最可靠且包容性最强。然而，模拟中18个红移约为5、恒星质量≥10¹¹太阳质量的星系中只有1个满足该选择；其余17个星系平均比采用尘埃模型下的颜色选择蓝约0.5星等。构建了一个改进的詹姆斯·韦布空间望远镜/近红外相机颜色 - 星等选择，能更完整地普查TNG300中红移约为5的大质量星系，同时排除观测文献标准识别出的尘埃多、低质量星系。研究了TNG300中红移为7、4和2时最庞大的近红外相机选择星系的后代，发现它们很少在红移为0时演变成最庞大的星系。总体而言，只有经历大量后期（红移约≤0.2）合并驱动增长的高红移大质量星系才会成为如今宇宙中最庞大的星系。这些结果共同表明，当前詹姆斯·韦布空间望远镜/近红外相机的观测选择未能识别出最庞大的高红移星系，并警示不要将高红移大质量星系解释为红移为0时最庞大星系的直接前身。
英文摘要
Early JWST/NIRCam surveys revealed a puzzling population of high-redshift massive galaxy candidates largely absent from previous rest-frame UV surveys. Spectroscopic follow-up has both confirmed and contested these candidates, whose potential overabundance may challenge traditional models of galaxy formation. In this study we evaluate the reliability of the photometric selections used to identify these candidates in observational data by applying them to galaxies in the TNG300 simulation with synthetic dust-attenuated photometry. Among the five observational selection criteria considered, we find that the selection presented by Pérez-González et al. is the most reliable and inclusive. Nevertheless, only 1 of the 18 galaxies at $z\sim5$ with $M_{\star} \geq 10^{11}~\mathrm{M_{\odot}}$ in the simulation satisfies this selection; the remaining 17 galaxies are on average $\sim0.5$ mag bluer than the color selection under the adopted dust model. We construct an improved JWST/NIRCam color-magnitude selection that provides a more complete census of massive galaxies at $z\sim5$ in TNG300 while excluding dusty, low-mass galaxies identified by criteria from the observational literature. We investigate the descendants of the most massive NIRCam-selected galaxies at $z=7,~4,$ and $2$ in TNG300, finding that they rarely evolve into the most massive galaxies by $z=0$. In general only the high-redshift massive galaxies that undergo substantial late-time ($z\lesssim0.2$) merger-driven growth become the most massive galaxies in the Universe today. Together these results suggest that current observational JWST/NIRCam selections are not identifying the most massive high-redshift galaxies, and caution against interpreting high-redshift massive galaxies as direct progenitors of the most massive galaxies at $z=0$.
CommentsManuscript contains 18 pages and 9 figures. Submitted to ApJ. Comments are welcome
