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Arxiv: EPOCHS Paper V. The dependence of galaxy formation on galaxy structure at z < 7 from JWST observations Published: 5/1/2024 11:06:13 AM Updated: 5/1/2024 11:06:13 AM

Paper abstract: We measure the broad impact of galaxy structure on galaxy formation byexamining the ongoing star formation and integrated star formation history asrevealed through the stellar masses of galaxies at z < 7 based on JWST CEERSdata from the Extended Groth Strip (EGS). Using the morphological catalog of3965 visually classified JWST galaxies from Ferreira et al. (2023), weinvestigate the evolution of stars, and when they form, as a function ofmorphological type as well as galaxies classified as passive and starburstthrough spectral energy distributions. Although disk galaxies dominate thestructures of galaxies at z < 7, we find that these disks are in generaleither `passive', or on the main-sequence of star formation, and do not containa large population of starburst galaxies. We also find no significantcorrelation between morphological type and the star formation rate or coloursof galaxies at z < 7. In fact, we find that the morphologically classified`spheroids' tend to be blue and are not found to be predominately passivesystems at z > 1.5. We also find that the stellar mass function for diskgalaxies does not evolve significantly during this time, whereas other galaxytypes, such as the peculiar population, evolve dramatically, declining at lowerredshifts. This indicates that massive peculiars are more common at higherredshifts. We further find that up to z ~ 7, the specific star formationrate (sSFR) does not vary with visual morphology, but strongly depends onstellar mass and internal galaxy mass density. This demonstrates that at earlyepochs galaxy assembly is a mass-driven, rather than a morphologically-driven,process. Quenching of star formation is therefore a mass-dominated processthroughout the universe's history, likely due to the presence of supermassiveblack holes.