TY - JOUR
T1 - Kennicutt–Schmidt relation of galaxies over 13 billion years in the COLIBRE hydrodynamical simulations
AU - Lagos, Claudia del P.
AU - Schaye, Joop
AU - Schaller, Matthieu
AU - Obreschkow, Danail
AU - Bahé, Yannick M.
AU - Benítez-Llambay, Alejandro
AU - Chaikin, Evgenii
AU - Correa, Camila
AU - Davis, Timothy A.
AU - Frenk, Carlos S.
AU - Huško, Filip
AU - Kaasinen, Melanie
AU - McGibbon, Robert J.
AU - Oman, Kyle
AU - Ploeckinger, Sylvia
AU - Richings, Alexander J.
AU - Trayford, James W.
AU - Wang, Jing
AU - Wright, Ruby J.
N1 - Publisher Copyright:
© The Author(s) 2026. Published by Oxford University Press on behalf of Royal Astronomical Society. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.
PY - 2026/6/2
Y1 - 2026/6/2
N2 - We investigate the correlation between star formation rate (SFR) surface density and gas surface density [known as the Kennicutt–Schmidt (KS) relation] at kiloparsec (kpc) scales across cosmic time ((Formula presented) ) for galaxies with stellar masses (Formula presented), using the COLIBRE state-of-the-art cosmological hydrodynamical simulations. These simulations feature on-the-fly non-equilibrium chemistry coupled to dust grain evolution and detailed radiative cooling down to (Formula presented) K, enabling direct predictions for the atomic (H i) and molecular (H(Formula presented) ) KS relations. At (Formula presented), COLIBRE reproduces the observed (spatially resolved) KS relations for H i and H(Formula presented), including the associated scatter, which we predict to be significantly correlated with stellar surface density, local specific SFR (sSFR), and gas metallicity. We show that the H i KS relation steepens for lower-mass galaxies, while the H(Formula presented) KS relation shifts to higher normalization in galaxies with higher sSFRs. The H(Formula presented) depletion time decreases by a factor of (Formula presented) from (Formula presented) to (Formula presented), primarily due to the decreasing gas-phase metallicity. This results in less H(Formula presented) and more H i being associated with a given SFR at higher redshift. We also find that galaxies with higher sSFRs have a larger molecular gas content and higher star formation efficiency per unit gas mass on kpc scales. The predicted evolution of the H(Formula presented) depletion time and its correlation with a galaxy’s sSFR agree remarkably well with observations in a wide redshift range, (Formula presented) .
AB - We investigate the correlation between star formation rate (SFR) surface density and gas surface density [known as the Kennicutt–Schmidt (KS) relation] at kiloparsec (kpc) scales across cosmic time ((Formula presented) ) for galaxies with stellar masses (Formula presented), using the COLIBRE state-of-the-art cosmological hydrodynamical simulations. These simulations feature on-the-fly non-equilibrium chemistry coupled to dust grain evolution and detailed radiative cooling down to (Formula presented) K, enabling direct predictions for the atomic (H i) and molecular (H(Formula presented) ) KS relations. At (Formula presented), COLIBRE reproduces the observed (spatially resolved) KS relations for H i and H(Formula presented), including the associated scatter, which we predict to be significantly correlated with stellar surface density, local specific SFR (sSFR), and gas metallicity. We show that the H i KS relation steepens for lower-mass galaxies, while the H(Formula presented) KS relation shifts to higher normalization in galaxies with higher sSFRs. The H(Formula presented) depletion time decreases by a factor of (Formula presented) from (Formula presented) to (Formula presented), primarily due to the decreasing gas-phase metallicity. This results in less H(Formula presented) and more H i being associated with a given SFR at higher redshift. We also find that galaxies with higher sSFRs have a larger molecular gas content and higher star formation efficiency per unit gas mass on kpc scales. The predicted evolution of the H(Formula presented) depletion time and its correlation with a galaxy’s sSFR agree remarkably well with observations in a wide redshift range, (Formula presented) .
KW - galaxies: evolution
KW - galaxies: ISM
KW - galaxies: star formation
KW - galaxy: formation
UR - https://www.scopus.com/pages/publications/105041119217
U2 - 10.1093/mnras/stag947
DO - 10.1093/mnras/stag947
M3 - Article
AN - SCOPUS:105041119217
SN - 0035-8711
VL - 549
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 2
M1 - stag947
ER -