From Carbon to Cobalt: Chemical Compositions and Ages of z ∼ 0.7 Quiescent Galaxies
We present elemental abundance patterns (C, N, Mg, Si, Ca, Ti, V, Cr, Fe, Co, and Ni) for a population of 135 massive quiescent galaxies at z ∼ 0.7 with ultra-deep rest-frame optical spectroscopy drawn from the LEGA-C survey. We derive average ages and elemental abundances in four bins of stellar ve...
| Main Authors: | , , , , , , , |
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| Format: | Article |
| Language: | English |
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IOP Publishing
2023-01-01
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| Series: | The Astrophysical Journal |
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| Online Access: | https://doi.org/10.3847/1538-4357/acc176 |
| _version_ | 1797695041215397888 |
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| author | Aliza G. Beverage Mariska Kriek Charlie Conroy Nathan R. Sandford Rachel Bezanson Marijn Franx Arjen van der Wel Daniel R. Weisz |
| author_facet | Aliza G. Beverage Mariska Kriek Charlie Conroy Nathan R. Sandford Rachel Bezanson Marijn Franx Arjen van der Wel Daniel R. Weisz |
| author_sort | Aliza G. Beverage |
| collection | DOAJ |
| description | We present elemental abundance patterns (C, N, Mg, Si, Ca, Ti, V, Cr, Fe, Co, and Ni) for a population of 135 massive quiescent galaxies at z ∼ 0.7 with ultra-deep rest-frame optical spectroscopy drawn from the LEGA-C survey. We derive average ages and elemental abundances in four bins of stellar velocity dispersion ( σ _v ) ranging from 150–250 km s ^−1 using a full-spectrum hierarchical Bayesian model. The resulting elemental abundance measurements are precise to 0.05 dex. The majority of elements, as well as the total metallicity and stellar age, show a positive correlation with σ _v . Thus, the highest dispersion galaxies formed the earliest and are the most metal-rich. We find only mild or nonsignificant trends between [X/Fe] and σ _v , suggesting that the average star formation timescale does not strongly depend on velocity dispersion. To first order, the abundance patterns of the z ∼ 0.7 quiescent galaxies are strikingly similar to those at z ∼ 0. However, at the lowest-velocity dispersions, the z ∼ 0.7 galaxies have slightly enhanced N, Mg, Ti, and Ni abundance ratios and earlier formation redshifts than their z ∼ 0 counterparts. Thus, while the higher-mass quiescent galaxy population shows little evolution, the low-mass quiescent galaxies population has grown significantly over the past 6 Gyr. Finally, the abundance patterns of both z ∼ 0 and z ∼ 0.7 quiescent galaxies differ considerably from theoretical prediction based on a chemical evolution model, indicating that our understanding of the enrichment histories of these galaxies is still very limited. |
| first_indexed | 2024-03-12T03:06:32Z |
| format | Article |
| id | doaj.art-d76e52355dac4205bbc6e42ef5945c83 |
| institution | Directory Open Access Journal |
| issn | 1538-4357 |
| language | English |
| last_indexed | 2024-03-12T03:06:32Z |
| publishDate | 2023-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | The Astrophysical Journal |
| spelling | doaj.art-d76e52355dac4205bbc6e42ef5945c832023-09-03T14:32:51ZengIOP PublishingThe Astrophysical Journal1538-43572023-01-01948214010.3847/1538-4357/acc176From Carbon to Cobalt: Chemical Compositions and Ages of z ∼ 0.7 Quiescent GalaxiesAliza G. Beverage0https://orcid.org/0000-0002-9861-4515Mariska Kriek1https://orcid.org/0000-0002-7613-9872Charlie Conroy2https://orcid.org/0000-0002-1590-8551Nathan R. Sandford3https://orcid.org/0000-0002-7393-3595Rachel Bezanson4https://orcid.org/0000-0001-5063-8254Marijn Franx5https://orcid.org/0000-0002-8871-3026Arjen van der Wel6https://orcid.org/0000-0002-5027-0135Daniel R. Weisz7https://orcid.org/0000-0002-6442-6030Department of Astronomy, University of California , Berkeley, CA 94720, USA ; abeverage@berkeley.eduLeiden Observatory, Leiden University , P.O. Box 9513, 2300 RA Leiden, The NetherlandsCenter for Astrophysics ∣ Harvard & Smithsonian , Cambridge, MA, 02138, USADepartment of Astronomy, University of California , Berkeley, CA 94720, USA ; abeverage@berkeley.eduDepartment of Physics and Astronomy, University of Pittsburgh , Pittsburgh, PA 15260, USALeiden Observatory, Leiden University , P.O. Box 9513, 2300 RA Leiden, The NetherlandsSterrenkundig Observatorium, Universiteit Gent , Krijgslaan 281 S9, B-9000 Gent, BelgiumDepartment of Astronomy, University of California , Berkeley, CA 94720, USA ; abeverage@berkeley.eduWe present elemental abundance patterns (C, N, Mg, Si, Ca, Ti, V, Cr, Fe, Co, and Ni) for a population of 135 massive quiescent galaxies at z ∼ 0.7 with ultra-deep rest-frame optical spectroscopy drawn from the LEGA-C survey. We derive average ages and elemental abundances in four bins of stellar velocity dispersion ( σ _v ) ranging from 150–250 km s ^−1 using a full-spectrum hierarchical Bayesian model. The resulting elemental abundance measurements are precise to 0.05 dex. The majority of elements, as well as the total metallicity and stellar age, show a positive correlation with σ _v . Thus, the highest dispersion galaxies formed the earliest and are the most metal-rich. We find only mild or nonsignificant trends between [X/Fe] and σ _v , suggesting that the average star formation timescale does not strongly depend on velocity dispersion. To first order, the abundance patterns of the z ∼ 0.7 quiescent galaxies are strikingly similar to those at z ∼ 0. However, at the lowest-velocity dispersions, the z ∼ 0.7 galaxies have slightly enhanced N, Mg, Ti, and Ni abundance ratios and earlier formation redshifts than their z ∼ 0 counterparts. Thus, while the higher-mass quiescent galaxy population shows little evolution, the low-mass quiescent galaxies population has grown significantly over the past 6 Gyr. Finally, the abundance patterns of both z ∼ 0 and z ∼ 0.7 quiescent galaxies differ considerably from theoretical prediction based on a chemical evolution model, indicating that our understanding of the enrichment histories of these galaxies is still very limited.https://doi.org/10.3847/1538-4357/acc176Galaxy abundancesEarly-type galaxiesGalaxy evolutionGalaxy stellar content |
| spellingShingle | Aliza G. Beverage Mariska Kriek Charlie Conroy Nathan R. Sandford Rachel Bezanson Marijn Franx Arjen van der Wel Daniel R. Weisz From Carbon to Cobalt: Chemical Compositions and Ages of z ∼ 0.7 Quiescent Galaxies The Astrophysical Journal Galaxy abundances Early-type galaxies Galaxy evolution Galaxy stellar content |
| title | From Carbon to Cobalt: Chemical Compositions and Ages of z ∼ 0.7 Quiescent Galaxies |
| title_full | From Carbon to Cobalt: Chemical Compositions and Ages of z ∼ 0.7 Quiescent Galaxies |
| title_fullStr | From Carbon to Cobalt: Chemical Compositions and Ages of z ∼ 0.7 Quiescent Galaxies |
| title_full_unstemmed | From Carbon to Cobalt: Chemical Compositions and Ages of z ∼ 0.7 Quiescent Galaxies |
| title_short | From Carbon to Cobalt: Chemical Compositions and Ages of z ∼ 0.7 Quiescent Galaxies |
| title_sort | from carbon to cobalt chemical compositions and ages of z ∼ 0 7 quiescent galaxies |
| topic | Galaxy abundances Early-type galaxies Galaxy evolution Galaxy stellar content |
| url | https://doi.org/10.3847/1538-4357/acc176 |
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