COSMOS-Web: A history of galaxy migrations over the stellar mass–star formation rate plane

¹ Aix Marseille Univ., CNRS, CNES, LAM, Marseille, France
² Cosmic Dawn Center (DAWN), Denmark
³ Niels Bohr Institute, University of Copenhagen, Jagtvej 128, DK-2200 Copenhagen, Denmark
⁴ Institut d’Astrophysique de Paris, UMR 7095, CNRS, Sorbonne Université, 98 bis Boulevard Arago, F-75014 Paris, France
⁵ The University of Texas at Austin, 2515 Speedway Blvd Stop C1400, Austin, TX 78712, USA
⁶ Université de Strasbourg, CNRS, Observatoire Astronomique de Strasbourg, UMR 7550, 67000 Strasbourg, France
⁷ Instituto de Astrofísica de Canarias (IAC), La Laguna E-38205, Spain
⁸ Observatoire de Paris, LERMA, PSL University, 61 Avenue de l’Observatoire, F-75014 Paris, France
⁹ Université Paris-Cité, 5 Rue Thomas Mann, 75014 Paris, France
¹⁰ Laboratory for Multiwavelength Astrophysics, School of Physics and Astronomy, Rochester Institute of Technology, 84 Lomb Memorial Drive, Rochester, NY 14623, USA
¹¹ Technical University of Munich, TUM School of Natural Sciences, Department of Physics, James-Franck-Str. 1, D-85748 Garching, Germany
¹² Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, D-85748 Garching, Germany
¹³ Instituto de Física y Astronomía, Universidad de Valparaíso, Avda. Gran Bretana 1111, Valparaíso, Chile
¹⁴ Department of Physics and Astronomy, University of Hawaii, Hilo, 200 W Kawili St, Hilo, HI 96720, USA
¹⁵ Caltech/IPAC, 1200 E. California Blvd., Pasadena, CA 91125, USA
¹⁶ Department of Computer Science, Aalto University, PO Box 15400 FI-00076 Espoo, Finland
¹⁷ Department of Physics, Faculty of Science, University of Helsinki, 00014 Helsinki, Finland
¹⁸ SOFIA Science Center, NASA Ames Research Center, Moffett Field, CA 94035, USA
¹⁹ Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA
²⁰ Kapteyn Astronomical Institute, University of Groningen, PO Box 800 9700 AV Groningen, The Netherlands
²¹ Purple Mountain Observatory, Chinese Academy of Sciences, 10 Yuanhua Road, Nanjing 210023, China
²² DTU Space, Technical University of Denmark, Elektrovej, Building 328, 2800 Kgs. Lyngby, Denmark
²³ Department of Physics, University of California Santa Barbara, Santa Barbara, CA 93106, USA
²⁴ European Space Agency (ESA), European Space Astronomy Centre (ESAC), Camino Bajo del Castillo s/n, 28692 Villanueva de la Cañada, Madrid, Spain
²⁵ Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, USA
²⁶ Department of Physics and Astronomy, UCLA, PAB 430 Portola Plaza, Box 951547, Los Angeles, CA 90095-1547, USA
²⁷ Department of Astronomy and Astrophysics, University of California, Santa Cruz, 1156 High Street, Santa Cruz, CA 95064, USA
²⁸ Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822, USA
²⁹ NASA Headquarters, 300 Hidden Figures Way, SE, Mary W. Jackson NASA HQ Building, Washington, DC 20546, USA
³⁰ University of Bologna – Department of Physics and Astronomy “Augusto Righi” (DIFA), Via Gobetti 93/2, I-40129 Bologna, Italy
³¹ INAF – Osservatorio di Astrofisica e Scienza dello Spazio, Via Gobetti 93/3, I-40129 Bologna, Italy
³² European Southern Observatory, Karl-Schwarzschild-Str. 2, D-85748 Garching bei München, Germany
³³ Astronomy Centre, University of Sussex Falmer, Brighton BN1 9QH, UK
³⁴ Department of Astronomy, University of Massachusetts, Amherst, MA 01003, USA

^⋆ Corresponding author; rafael.arango-toro@lam.fr

Received: 7 October 2024
Accepted: 11 March 2025

Abstract

Context. The stellar mass-star formation rate (M_⋆ − SFR) plane is an essential diagnostic to separate galaxy populations. However, we still lack a clear picture of how galaxies move within this plane along cosmic time.

Aims. This study aims to provide an observational description of galaxy migrations in the M_⋆ − SFR plane based on the reconstructed star formation histories (SFH) of a sample of galaxies at redshift z < 4. Ultimately, this study seeks to provide insight into physical processes driving star formation.

Methods. We used data from the COSMOS field, which provides extensive multi-wavelength coverage. We selected a sample of 299131 galaxies at z < 4 with the COSMOS-Web NIRCam data at a magnitude of m_F444W < 27 over a large area of 0.54 deg². We utilized the SED modeling code CIGALE, which incorporates non-parametric SFHs, to derive the physical properties and reconstruct the SFHs of this galaxy sample. To characterize the SFHs and interpret the galaxies’ movements on the M_⋆ − SFR plane, for each galaxy we also defined a migration vector in order to track the direction (Φ_Δt[deg]) and velocity norm (r_Δt[dex/Gyr]) of the evolutionary path over the M_⋆ − SFR plane. We quantified the quality at which these migration vectors can be reconstructed using the HORIZON-AGN cosmological hydrodynamical simulation.

Results. We find that galaxies within the main sequence exhibit the lowest amplitude in their migration and a large dispersion in the direction of their movements. We interpret this result as galaxies oscillating within the galaxy main sequence. By using their migration vectors to find the position of main-sequence progenitors, we obtained that most of the progenitors were already on the main sequence as defined one billion years earlier. We find that galaxies within the starburst or passive region of the M_⋆ − SFR plane have very homogeneous properties in terms of recent SFH (< 1 Gyr). Starburst galaxies assembled half of their stellar mass within the last 350 Myr, and this population originates from the main sequence. Galaxies in the passive region of the plane show a homogeneous declining SFH over the full considered redshift range. We identified massive galaxies already in the passive region at 3.5 < z < 4, and their number density increases continuously with cosmic time. The progenitors of passive galaxies are distributed over a large range of SFRs, with less than 20% of passive galaxies being starburst 1 Gyr earlier, thus shedding light on rapid quenching channels.

Conclusions. Using reconstructed SFHs up to z < 4, we propose a coherent picture of how galaxies migrate over cosmic time in the M_⋆ − SFR plane, highlighting the connection between major phases in the SFH.