J/A+A/690/A150 Mass-Metallicity Relation of quiescent galaxies (Bevacqua+, 2024)
A new perspective on the mass-metallicity relation of quiescent galaxies from
the LEGA-C survey.
Bevacqua D., Saracco P., Boecker A., D'Ago G., De Lucia G., De Propris R.,
La Barbera F., Pasquali A., Spiniello C., Tortora C.
<Astron. Astrophys. 690, A150 (2024)>
=2024A&A...690A.150B 2024A&A...690A.150B (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies ; Stars, masers ; Stars, ages
Keywords: galaxies: abundances - galaxies: elliptical and lenticular, cD -
galaxies: evolution - galaxies: formation - galaxies: high-redshift -
galaxies: stellar content
Abstract:
We investigate the stellar Mass-Metallicity Relation (MZR) using a
sample of 637 quiescent galaxies with 10.4≤log(M*/M☉)<11.7
selected from the LEGA-C survey at 0.6≤z≤1. We derive mass-weighted
stellar metallicities using full-spectral fitting. We find that while
lower-mass galaxies are both metal-rich and -poor, there are no
metal-poor galaxies at high masses, and that metallicity is bounded at
low values by a mass-dependent lower limit. This lower limit increases
with mass, empirically defining a MEtallicity-Mass Exclusion (MEME)
zone. We find that the spectral index MgFe=SQRT(Mgb*Fe4383), a proxy
for the stellar metallicity, also shows a mass-dependent lower limit
resembling the MEME relation. Crucially MgFe is independent of stellar
population models and fitting methods. By constructing the Metallicity
Enrichment Histories, we find that, after the first Gyr, the Star
Formation History of galaxies has a mild impact on the observed
metallicity distribution. Finally, from the average formation times,
we find that galaxies populate differently the metallicity-mass plane
at different cosmic times, and that the MEME limit is recovered by
galaxies that formed at z≥3. Our work suggests that the stellar
metallicity of quiescent galaxies is bounded by a lower limit which
increases with the stellar mass. On the other hand, low-mass galaxies
can have metallicities as high as galaxies ∼1dex more massive. This
suggests that, at log(M*/M☉)≥10.4, rather than lower-mass
galaxies being systematically less metallic, the observed MZR might be
a consequence of the lack of massive, metal-poor galaxies.
Description:
We study a large sample of quiescent galaxies selected from
LEGA-C. LEGA-C is a spectroscopic survey of galaxies observed at
intermediate redshifts (z∼0.6-1.0) in the Cosmological Evolution
Survey (COSMOS) field (Scoville et al. 2007ApJS..172....1S 2007ApJS..172....1S), using the
VIsible Multi-Object Spectrograph on the Very Large Telescope (VLT).
The final sample consists of 637 quiescent galaxies.
We estimate the mass-weighted ages and metallicities by fitting the
LEGA-C spectra using the penalized pixel fitting (pPXF) method and
code described in Cappellari & Emsellem (2004PASP..116..138C 2004PASP..116..138C);
Cappellari (2017MNRAS.466..798C 2017MNRAS.466..798C, 2023, updated to version v8.2.2).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 32 636 Estimated stellar population parameters
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See also:
J/ApJS/206/8 : COSMOS/UltraVISTA Ks-selected catalogs v4.1 (Muzzin+, 2013)
J/ApJS/256/44 : LEGA-C DR3: high-quality galaxies spectra (van der Wel+, 2021)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- LEGA-C Mask number and LEGA-C ID of the
file associated with the spectrum
13- 16 F4.2 Gyr Age Mass-weighted age estimated from fits
using equation 1
18- 22 F5.2 --- [M/H] Mass-weighted metallicity estimated from fits
using equation 2
24- 27 F4.2 Gyr tform Average formation time estimated
using equation 3
29- 32 F4.2 Gyr Dtau Dtau = tau_95 - tau_5 (1)
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Note (1): Delta tau = tau_95 - tau_5,
where tau_x is the time at which a galaxy formed x-percent of its mass, as
measured from its SFH (see section 5.1).
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Acknowledgements:
Davide Bevacqua, davide.bevacqua(at)inaf.it
References:
Bevacqua et al., 2023MNRAS.525.4219B 2023MNRAS.525.4219B,
The elemental abundance of quiescent galaxies in the LEGA-C survey:
the (non-)evolution of [alpha/Fe] from z = 0.75 to z = 0.
(End) Patricia Vannier CDS 18-Jul-2024