The connection between stellar mass, age, and quenching time-scale in massive quiescent galaxies at z ≃ 1
Abstract
We present a spectrophotometric study of a mass-complete sample of quiescent galaxies at 1.0 < z < 1.3 with $\mathrm{log_{10}}(M_{\star }/\mathrm{{\rm M}_{\odot }}) \ge 10.3$ drawn from the VANDELS survey, exploring the relationship between stellar mass, age, and star-formation history. Within our sample of 114 galaxies, we derive a stellar-mass versus stellar-age relation with a slope of $1.20^{+0.28}_{-0.27}$ Gyr per decade in stellar mass. When combined with recent literature results, we find evidence that the slope of this relation remains consistent over the redshift interval 0 < z < 4. The galaxies within the VANDELS quiescent sample display a wide range of star-formation histories, with a mean quenching time-scale of 1.4 ± 0.1 Gyr. We also find a large scatter in the quenching time-scales of the VANDELS quiescent galaxies, in agreement with previous evidence that galaxies at z ~ 1 cease star formation via multiple mechanisms. We then focus on the oldest galaxies in our sample, finding that the number density of galaxies that quenched before z = 3 with stellar masses $\mathrm{log_{10}}(M_{\star }/\mathrm{{\rm M}_{\odot }}) \ge 10.6$ is $1.12_{-0.72}^{+1.47} \times 10^{-5} \ \mathrm{Mpc}^{-3}$. Although uncertain, this estimate is in good agreement with the latest observational results at 3 < z < 4, tentatively suggesting that neither rejuvenation nor merger events are playing a major role in the evolution of the oldest massive quiescent galaxies within the redshift interval 1 < z < 3.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- June 2023
- DOI:
- 10.1093/mnras/stad773
- arXiv:
- arXiv:2303.06107
- Bibcode:
- 2023MNRAS.521.5400H
- Keywords:
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- galaxies: evolution;
- galaxies: high-redshift;
- galaxies: star formation;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- Accepted for publication in MNRAS, 11 pages, 6 figures