COSMOS-Web : The emergence of the Hubble sequence

Loading...
Thumbnail Image

Access rights

openAccess
CC BY
publishedVersion

URL

Journal Title

Journal ISSN

Volume Title

A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä

Major/Subject

Mcode

Degree programme

Language

en

Pages

20

Series

Astronomy & Astrophysics, Volume 704, pp. 1-20

Abstract

Context. The first JWST deep surveys have expanded our understanding of the morphological evolution of galaxies across cosmic time. The improved spatial resolution and near-infrared (NIR) coverage have revealed a population of morphologically evolved galaxies at very early epochs. However, all previous works are based on relatively small samples; this has prevented accurate probing of the morphological diversity at cosmic dawn. Aims. Leveraging the wide area coverage of the COSMOS-Web survey, we quantified the abundance of different morphological types from z ∼ 7 with unprecedented statistics and established robust constraints on the epoch of emergence of the Hubble sequence. Methods. We measured the global morphologies (spheroids, disk-dominated, bulge-dominated, peculiar) and resolved morphologies (stellar bars) for about 400 000 galaxies down to F150W = 27 using deep learning; this represents an increase of two orders of magnitude over previous studies. We provide reference stellar mass functions (SMFs) of different morphologies between z ∼ 0.2 and z ∼ 7 as well as best-fit parameters to inform models of galaxy formation. All catalogs and data are made publicly available. Results. At redshift z > 4.5, the massive galaxy population (log M*/M⊙ > 10) is dominated by disturbed morphologies (∼ 70%), even in the optical rest frame, and very compact objects (∼ 30%) with effective radii smaller than ∼ 500 pc. This confirms that a significant fraction of the star formation at cosmic dawn occurs in very dense regions, although the stellar mass for these systems could be overestimated. Galaxies with Hubble-type morphologies, including bulge- and disk-dominated galaxies, arose rapidly around z ∼ 4 and dominate the morphological diversity of massive galaxies as early as z ∼ 3. Using stellar bars as a proxy, we speculate that stellar disks in massive galaxies might have been common (> 50%) among the star-forming population since cosmic noon (z ∼ 2-2.5) and formed as early as z ∼ 7. Massive quenched galaxies are predominantly bulge-dominated from z ∼ 4 onward, suggesting that morphological transformations briefly precede or are simultaneous to quenching mechanisms at the high-mass end. Low-mass (log M*/M⊙ < 10) quenched galaxies are typically disk-dominated, which points to different quenching routes at the two ends of the stellar mass spectrum from cosmic dawn.

Description

Publisher Copyright: © The Authors 2025.

Other note

Citation

Huertas-Company, M, Shuntov, M, Dong, Y, Walmsley, M, Ilbert, O, Mccracken, H J, Akins, H B, Allen, N, Casey, C M, Costantin, L, Daddi, E, Dekel, A, Franco, M, Garland, I L, Géron, T, Gozaliasl, G, Hirschmann, M, Kartaltepe, J S, Koekemoer, A M, Lintott, C, Liu, D, Lucas, R, Masters, K, Pacucci, F, Paquereau, L, Pérez-González, P G, Rhodes, J D, Robertson, B E, Simmons, B, Smethurst, R, Toft, S & Yang, L 2025, 'COSMOS-Web : The emergence of the Hubble sequence', Astronomy & Astrophysics, vol. 704, A94, pp. 1-20. https://doi.org/10.1051/0004-6361/202553782