LEGA-C stellar populations scaling relations. I: Chemo-archaeological downsizing trends at z~0.7

Abstract

We analyze stellar population properties of 552 galaxies at redshift 0.6<z<0.77 from the LEGA-C spectroscopic survey. This first paper in a series presents the catalog of revised absorption indices for LEGA-C DR3 and inferred physical parameters, and derives benchmark scaling relations for the general massive galaxy population at intermediate redshift. We estimate light-weighted mean ages and stellar metallicities by interpreting key stellar absorption features and rizYJ photometry in a Bayesian framework with a comprehensive library of model spectra based on stochastic star formation and metallicity histories and dust attenuations. We discuss systematic uncertainties within our method and compared to other spectral fitting approaches. We derive volume-weighted scaling relations of light-weighted mean ages and stellar metallicities with stellar mass for the general galaxy population at <z>=0.7 and masses >10^10Msun. The downsizing trends observed locally were already in place 6 Gyr ago. We observe bimodal age distribution as a function of mass, transitioning around 10^11Msun. No bimodality appears in the stellar metallicity-mass relation, which changes from steep to flat across 10^10.8Msun. Similar trends emerge for age and metallicity with velocity dispersion, but with sharper transition from young to old around log(sigma)=2.3. Differences with respect to trens with stellar mass suggest that age primarily depends on velocity dispersion below and above the transition regime, while both stellar mass and velocity dispersion contribute to stellar metallicity. The catalogs of revised absorption index measurements for LEGA-C DR3 and inferred stellar population physical parameters will be released to public repositories. (Abridged)

20 pages of main text, 10 pages Appendices with discussion on systematics, 10 figures in main text, 8 figures in Appendices; Resubmitted to A&A after revision. This is the first paper of a series, accompanying arXiv:2511.11805

References in corpus (103)

• Stellar population synthesis at the resolution of 2003
• Galactic Stellar and Substellar Initial Mass Function
• Cosmic Star Formation History
• The Origin of the Mass--Metallicity Relation: Insights from 53,000 Star-Forming Galaxies in the SDSS
• Stellar Masses and Star Formation Histories for 10^5 Galaxies from the Sloan Digital Sky Survey
• Galaxy Bimodality due to Cold Flows and Shock Heating
• The epochs of early-type galaxy formation as a function of environment
• Quantifying the bimodal color-magnitude distribution of galaxies
• Physical Models of Galaxy Formation in a Cosmological Framework
• The Dependence of Star Formation History and Internal Structure on Stellar Mass for 10^5 Low-Redshift Galaxies
• A simple model to interpret the ultraviolet, optical and infrared emission from galaxies
• The ages and metallicities of galaxies in the local universe
• The size distribution of galaxies in the Sloan Digital Sky Survey
• The SAURON project - IV. The mass-to-light ratio, the virial mass estimator and the fundamental plane of elliptical and lenticular galaxies
• The Evolution of the Stellar Mass Functions of Star-Forming and Quiescent Galaxies to z = 4 from the COSMOS/UltraVISTA Survey
• AMAZE. I. The evolution of the mass-metallicity relation at z>3
• Galaxy bimodality versus stellar mass and environment
• Gas-regulation of galaxies: the evolution of the cosmic sSFR, the metallicity-mass-SFR relation and the stellar content of haloes
• Stellar population models of Lick indices with variable element abundance ratios
• An updated MILES stellar library and stellar population models
• PARSEC evolutionary tracks of massive stars up to $350M_{\odot }$ at metallicities 0.0001$\le Z\le$0.04
• The Stellar, Gas and Dynamical Masses of Star-Forming Galaxies at z~2
• COLD GASS, an IRAM legacy survey of molecular gas in massive galaxies: I. Relations between H2, HI, stellar content and structural properties
• Structure and star formation in galaxies out to z=3: evidence for surface density dependent evolution and upsizing
• The Atlas3D Project - XXX. Star formation histories and stellar population scaling relations of early-type galaxies
• A Public Ks-selected Catalog in the COSMOS/UltraVISTA Field: Photometry, Photometric Redshifts and Stellar Population Parameters
• xGASS: Total cold gas scaling relations and molecular-to-atomic gas ratios of galaxies in the local Universe
• Stellar Population Diagnostics of Elliptical Galaxy Formation
• The Mass-Metallicity and the Fundamental Metallicity Relation revisited on a fully Te-based abundance scale for galaxies
• Ages and metallicities of early-type galaxies in the SDSS: new insight into the physical origin of the colour-magnitude and the Mg2-sigmaV relations
• The Many Manifestations of Downsizing: Hierarchical Galaxy Formation Models confront Observations
• The SAURON project - XVII. Stellar population analysis of the absorption line strength maps of 48 early-type galaxies
• Modelling the nebular emission from primeval to present-day star-forming galaxies
• Full spectrum fitting with photometry in pPXF: stellar population versus dynamical masses, non-parametric star formation history and metallicity for 3200 LEGA-C galaxies at redshift z~0.8
• The evolving relations between size, mass, surface density, and star formation in 3x10^4 galaxies since z=2
• Higher-order Balmer line indices in alpha/Fe-enhanced stellar population models
• The Metallicity of Galaxy Disks: Infall versus Outflow
• An Older, More Quiescent Universe from Panchromatic SED Fitting of the 3D-HST Survey
• Observational constraints on the origin of the elements. IV: The standard composition of the Sun
• Semi-empirical analysis of Sloan Digital Sky Survey galaxies: II. The bimodality of the galaxy population revisited
• The VANDELS survey: the star-formation histories of massive quiescent galaxies at 1.0 < z < 1.3
• The star formation history of CALIFA galaxies: Radial structures
• The VLT LEGA-C Spectroscopic Survey: The Physics of Galaxies at a Lookback Time of 7 Gyr
• Colors, magnitudes and velocity dispersions in early-type galaxies: Implications for galaxy ages and metallicities
• Charting the evolution of the ages and metallicities of massive galaxies since z=0.7
• The Cosmic Evolution of Metallicity from the SDSS Fossil Record
• Both starvation and outflows drive galaxy quenching
• The Chemical Evolution of Star-Forming Galaxies Over the Last 11 Billion Years
• A Model for Star Formation, Gas Flows and Chemical Evolution in Galaxies at High Redshifts
• Fast, Slow, Early, Late: Quenching Massive Galaxies at z~0.8
• On the Size and Comoving Mass Density Evolution of Early-Type Galaxies
• Stellar populations from spectroscopy of a large sample of quiescent galaxies at z > 1: Measuring the contribution of progenitor bias to early size growth
• The Assembly Histories of Quiescent Galaxies Since z=0.7 from Absorption Line Spectroscopy
• SDSS-IV MaNGA: pyPipe3D analysis release for 10,000 galaxies
• Spectral Modelling of Star-Forming Regions in the Ultraviolet: Stellar Metallicity Diagnostics for High Redshift Galaxies
• Dissecting the Red Sequence--I. Star Formation Histories of Quiescent Galaxies: The Color-Magnitude vs. the Color-Sigma Relation
• Constraints on the production and escape of ionizing radiation from the emission-line spectra of metal-poor star-forming galaxies
• Deep Absorption Line Studies of Quiescent Galaxies at z~2: The Dynamical Mass-Size Relation, and First Constraints on the Fundamental plane
• Revealing velocity dispersion as the best indicator of a galaxy's color, compared to stellar mass, surface mass density or morphology
• Stellar Ages and Metallicities of Central and Satellite Galaxies: Implications for Galaxy Formation and Evolution
• The VANDELS survey: the stellar metallicities of star-forming galaxies at 2.5 < z < 5.0
• Stellar Absorption Line Analysis of Local Star-Forming Galaxies: The Relation Between Stellar Mass, Metallicity, Dust Attenuation and Star Formation Rate
• Quenching as a Contest between Galaxy Halos and their Central Black Holes
• The Large Early Galaxy Astrophysics Census (LEGA-C) Data Release II: dynamical and stellar population properties of z ~< 1 galaxies in the COSMOS field
• Fast and slow paths to quiescence: ages and sizes of 400 quiescent galaxies from the LEGA-C survey
• Stellar metallicity of star-forming galaxies at z ~ 3
• Evolution of Cluster Red-Sequence Galaxies from redshift 0.8 to 0.4: ages, metallicities and morphologies
• Spatially Resolved Stellar Kinematics from LEGA-C: Increased Rotational Support in z~0.8 Quiescent Galaxies
• The Rise and Fall of Galaxy Activity in Dark Matter Haloes
• The DEEP2 Galaxy Redshift Survey: Mean Ages and Metallicities of Red Field Galaxies at z ~ 0.9 from Stacked Keck/DEIMOS Spectra
• Galaxy evolution across environments as probed by the ages, stellar metallicities and [alpha/Fe] of central and satellite galaxies
• CLEAR I: Ages and Metallicities of Quiescent Galaxies at $1.0<\mathbf{z}<1.8$ Derived from Deep Hubble Space Telescope Grism Data
• GMASS Ultradeep Spectroscopy of Galaxies at redshift z~2. I. The stellar metallicity
• RXJ0152.7-1357: Stellar populations in an X-ray luminous galaxy cluster at z=0.83
• Stellar Populations of over one thousand $z\sim 0.8$ Galaxies from LEGA-C: Ages and Star Formation Histories from D${}_n$4000 and H$\delta$
• The SAMI Galaxy Survey: gravitational potential and surface density drive stellar populations -- I. early-type galaxies
• Rejuvenation in $z\sim 0.8$ quiescent galaxies in LEGA-C
• Stellar Metallicities and Elemental Abundance Ratios of z~1.4 Massive Quiescent Galaxies
• Early-type galaxies in the PEARS survey: Probing the stellar populations at moderate redshift
• SFHs OF $Z\sim 1$ Galaxies in LEGA-C
• The Rapid Build-up of Massive Early-type Galaxies. Supersolar Metallicity, High Velocity Dispersion and Young Age for an ETG at z=3.35
• An analytical model for galaxy metallicity: What do metallicity relations tell us about star formation and outflow?
• X-shooter Spectroscopy and HST Imaging of 15 Ultra Massive Quiescent Galaxies at $z\gtrsim 2$
• The Mass Scale of High-Redshift Galaxies: Virial Mass Estimates Calibrated with Stellar Dynamical Models from LEGA-C
• The stellar metallicities of massive quiescent galaxies at 1.0 < z < 1.3 from KMOS+VANDELS
• Old age and super-solar metallicity in a massive z~1.4 early-type galaxy from VLT/X-Shooter spectroscopy
• The Fundamental Plane in the LEGA-C Survey: unraveling the $M/L$ variations of massive star-forming and quiescent galaxies at $z\sim 0.8$
• High-resolution, 3D radiative transfer modelling III. The DustPedia barred galaxies
• A combined VANDELS and LEGA-C study: the evolution of quiescent galaxy size, stellar mass and age from $\text{z}=0.6$ to $\text{z}=1.3$
• Inverse stellar population age gradients of post-starburst galaxies at z=0.8 with LEGA-C
• Evolution of the Stellar Mass-Metallicity Relation. II. Constraints on Galactic Outflows from the Mg Abundances of Quiescent Galaxies
• From Carbon to Cobalt: Chemical compositions and ages of $z\sim 0.7$ quiescent galaxies
• Stellar Dynamical Models for 797 $z\sim 0.8$ Galaxies from LEGA-C
• Molecular Gas Reservoirs in Massive Quiescent Galaxies at $\mathrm{z}\sim 0.7$ Linked to Late Time Star Formation
• The dark side of galaxy stellar populations I: The stellar-to-halo mass relation and the velocity dispersion - halo mass relation
• WEAVE-StePS. A stellar population survey using WEAVE at WHT
• Stellar mass as the "glocal" driver of galaxies' stellar population properties
• Towards precise galaxy evolution: a comparison between spectral indices of $z\sim 1$ galaxies in the IllustrisTNG simulation and the LEGA-C survey
• Baryonic properties of nearby galaxies across the stellar-to-total dynamical mass relation
• More is better: Strong constraints on the stellar properties of LEGA-C z ~ 1 galaxies with Prospector
• A new perspective on the stellar Mass-Metallicity Relation of quiescent galaxies from the LEGA-C survey
• FIGS: Spectral fitting constraints on the star formation history of massive galaxies since Cosmic Noon
• Re-assessing the stellar population scaling relations of the galaxies in the Local Universe

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• LEGA-C stellar populations scaling relations. II: Dissecting mass-complete archaeological trends and their evolution since z~0.7 with LEGA-C and SDSS
• Correcting the fiber-aperture bias affecting galaxy stellar populations in the Sloan Digital Sky Survey. Aperture corrections to absorption indices based on CALIFA integral field observations