We present a framework for high-redshift ($z \geq 7$) galaxy formation that traces their dark matter (DM) and baryonic assembly in four cosmologies: Cold Dark Matter (CDM) and Warm Dark Matter (WDM) with particle masses of $m_x =$ 1.5, 3 and 5 ${\rm keV}$. We use the same astrophysical parameters regulating star formation and feedback, chosen to match current observations of the evolving ultra violet luminosity function (UV LF). We find that the assembly of observable (with current and upcoming instruments) galaxies in CDM and $m_x \geq 3 {\rm keV}$ WDM results in similar halo mass to light ratios (M/L), stellar mass densities (SMDs) and UV LFs. However the suppression of small-scale structure leads to a notably delayed and subsequently more rapid stellar assembly in the $1.5 {\rm keV}$ WDM model. Thus galaxy assembly in $m_x \leq 2 {\rm keV}$ WDM cosmologies is characterized by: (i) a dearth of small-mass halos hosting faint galaxies; and (ii) a younger, more UV bright stellar population, for a given stellar mass. The higher M/L ratio (effect ii) partially compensates for the dearth of small-mass halos (effect i), making the resulting UV LFs closer to CDM than expected from simple estimates of halo abundances. We find that the redshift evolution of the SMD is a powerful probe of the nature of DM. Integrating down to a limit of $M_{UV} =-16.5$ for the James Webb Space Telescope (JWST), the SMD evolves as $\log$(SMD)$\propto -0.63 (1+z)$ in $m_x = 1.5 {\rm keV}$ WDM, as compared to $\log$(SMD)$\propto -0.44 (1+z)$ in CDM. Thus high-redshift stellar assembly provides a powerful testbed for WDM models, accessible with the upcoming JWST.
CASCO: Cosmological and AStrophysical parameters from Cosmological simulations and Observations IV. Testing warm dark matter cosmologies with galaxy scaling relations: A joint simulation-observation study using DREAMS simulations
INAF – Osservatorio Astronomico di Capodimonte（意大利国家天体物理研究所卡波迪蒙特天文台）；Dipartimento di Fisica “E. Pancini”, Università degli studi di Napoli Federico II（那不勒斯费德里科二世大学E. Pancini物理系）；INFN, Sez. di Napoli（意大利国家核物理研究院那不勒斯分部）；The NSF-Simons AI Institute for Cosmic Origins, University of Texas at Austin（德克萨斯大学奥斯汀分校NSF-Simons宇宙起源AI研究所）；Departments of Statistics and Data Sciences, University of Texas at Austin（德克萨斯大学奥斯汀分校统计与数据科学系）；Department of Astronomy, University of Virginia（弗吉尼亚大学天文系）；Center for Computational Astrophysics, Flatiron Institute（平顿研究所计算天体物理学中心）；Virginia Institute for Theoretical Astronomy, University of Virginia（弗吉尼亚理论天文研究所）；Department of Astrophysical Sciences, Princeton University（普林斯顿大学天体物理学科学系）
