COSMOS-Web: Stellar mass assembly in relation to dark matter halos across 0.2 < z < 12 of cosmic history

¹ Cosmic Dawn Center (DAWN), Denmark
² Niels Bohr Institute, University of Copenhagen, Jagtvej 128, 2200 Copenhagen, Denmark
³ Aix Marseille Univ, CNRS, CNES, LAM, Marseille, France
⁴ The University of Texas at Austin, 2515 Speedway Blvd Stop C1400, Austin, TX 78712, USA
⁵ Laboratory for Multiwavelength Astrophysics, School of Physics and Astronomy, Rochester Institute of Technology, 84 Lomb Memorial Drive, Rochester, NY 14623, USA
⁶ Institut d’Astrophysique de Paris, UMR 7095, CNRS, Sorbonne Université, 98 bis boulevard Arago, F-75014 Paris, France
⁷ Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA
⁸ Université de Strasbourg, CNRS, Observatoire astronomique de Strasbourg, UMR 7550, 67000 Strasbourg, France
⁹ Department of Physics and Astronomy, University of Hawaii, Hilo, 200 W Kawili St, Hilo, HI 96720, USA
¹⁰ Caltech/IPAC, 1200 E. California Blvd., Pasadena, CA 91125, USA
¹¹ Department of Computer Science, Aalto University, P.O. Box 15400 FI-00076 Espoo, Finland
¹² DTU Space, Technical University of Denmark, Elektrovej, Building 328, 2800 Kgs. Lyngby, Denmark
¹³ Center for Computational Astrophysics, Flatiron Institute, 162 Fifth Avenue, New York, NY 10010, USA
¹⁴ Institute of Physics, GalSpec, Ecole Polytechnique Federale de Lausanne, Observatoire de Sauverny, Chemin Pegasi 51, 1290 Versoix, Switzerland
¹⁵ NAF, Astronomical Observatory of Trieste, Via Tiepolo 11, 34131 Trieste, Italy
¹⁶ Instituto de Astrofísica de Canarias (IAC), La Laguna E-38205, Spain
¹⁷ Observatoire de Paris, LERMA, PSL University, 61 avenue de l’Observatoire, F-75014 Paris, France
¹⁸ Université Paris-Cité, 5 Rue Thomas Mann, 75014 Paris, France
¹⁹ Universidad de La Laguna, Avda. Astrofísico Fco. Sanchez, La Laguna, Tenerife, Spain
²⁰ Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544, USA
²¹ NASA-Goddard Space Flight Center, Code 662, Greenbelt, MD 20771, USA
²² Purple Mountain Observatory, Chinese Academy of Sciences, 10 Yuanhua Road, Nanjing 210023, China
²³ Centre for Extragalactic Astronomy, Durham University, South Road, Durham DH1 3LE, UK
²⁴ Department of Physics, Northeastern University, 360 Huntington Avenue, Boston, MA 02115, USA
²⁵ Department of Astronomy, University of Geneva, Chemin Pegasi 51, 1290 Versoix, Switzerland
²⁶ Istituto Nazionale di Astrofisica (INAF), Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5, 35122 Padova, Italy
²⁷ Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, USA
²⁸ Department of Physics and Astronomy, UCLA, PAB 430 Portola Plaza, Box 951547 Los Angeles, CA 90095-1547, USA
²⁹ Department of Astronomy and Astrophysics, University of California, Santa Cruz, 1156 High Street, Santa Cruz, CA 95064, USA
³⁰ Institute for Astronomy, University of Hawai’i at Manoa, 2680 Woodlawn Drive, Honolulu, HI 96822, USA
³¹ Sorbonne Université, Observatoire de Paris, PSL research university, CNRS, LERMA, 75014 Paris, France
³² European Southern Observatory, Karl-Schwarzschild-Str. 2, 85748 Garching, Germany
³³ Department of Astronomy, University of Massachusetts, Amherst, MA 01003, USA
³⁴ Astronomy Centre, University of Sussex, Falmer, Brighton BN1 9QH, UK
³⁵ Institute of Space Sciences and Astronomy, University of Malta, Msida MSD 2080, Malta

^⋆ Corresponding author; marko.shuntov@nbi.ku.dk

Received: 10 October 2024
Accepted: 17 January 2025

Abstract

We study the stellar mass assembly of galaxies via the stellar mass function (SMF) and the coevolution with dark matter halos via abundance matching in the largest redshift range to date, 0.2 < z < 12. We used the 0.53 deg² imaged by JWST from the COSMOS-Web survey, in combination with ancillary imaging in over 30 photometric bands, to select highly complete samples (down to log M_⋆/M_⊙ = 7.5 − 8.8) in 15 redshift bins. Our results show that the normalization of the SMF monotonically decreases from z = 0.2 to z = 12 with strong mass-dependent evolution. At z > 5, we find increased abundances of massive (log M_⋆/M_⊙ > 10.5) systems compared to predictions from semi-analytical models and hydrodynamical simulations. These findings challenge traditional galaxy formation models by implying integrated star formation efficiencies (SFEs) of ϵ ⋆ ≡M_⋆ f_b − 1 M_halo⁻¹ ≳ 0.5. We find a flattening of the SMF at the high-mass end that is better described by a double power law at z > 5.5, after correcting for the Eddington bias. At z ≲ 5.5, it transitions to a Schechter law, which coincides with the emergence of the first massive quiescent galaxies in the Universe, indicating that physical mechanisms that suppress galaxy growth start to take place at z ∼ 5.5 on a global scale. By integrating the SMF, we trace the cosmic stellar mass density and infer the star formation rate density, which at z > 7.5 agrees remarkably with recent JWST UV luminosity function-derived estimates. This agreement solidifies the emerging picture of rapid galaxy formation leading to increased abundances of bright and massive galaxies in the first ∼0.7 Gyr. However, at z ≲ 3.5, we find significant tension (∼0.3 dex) with the cosmic star formation (SF) history from instantaneous SF measures, the causes of which remain poorly understood. We infer the stellar-to-halo mass relation (SHMR) and the SFE from abundance matching out to z = 12, finding a non-monotonic evolution. The SFE has the characteristic strong dependence with mass in the range of 0.02 − 0.2, and mildly decreases at the low-mass end out to z ∼ 3.5. At z ∼ 3.5, there is an upturn and the SFE increases sharply from ∼0.1 to approach a high SFE of 0.8 − 1 by z ∼ 10 for log(M_h/M_⊙)≈11.5, albeit with large uncertainties. Finally, we use the SHMR to track the SFE and stellar mass growth throughout the halo history and find that they do not grow at the same rate – from the earliest times up until z ∼ 3.5 the halo growth rate outpaces galaxy assembly, but at z > 3.5 halo growth stagnates and accumulated gas reservoirs keep the SF going and galaxies outpace halos.