In:
The Astrophysical Journal, American Astronomical Society, Vol. 908, No. 2 ( 2021-02-01), p. 120-
Abstract:
Using the near-IR spectroscopy of the MOSFIRE Deep Evolution Field survey, we investigate the role of the local environment in the gas-phase metallicity of galaxies. The local environment measurements are derived from accurate and uniformly calculated photometric redshifts with well-calibrated probability distributions. Based on rest-frame optical emission lines, [N ii ] λ 6584 and H α , we measure gas-phase oxygen abundances of 167 galaxies at 1.37 ≤ z ≤ 1.7 and 303 galaxies at 2.09 ≤ z ≤ 2.61, located in diverse environments. We find that at z ∼ 1.5, the average metallicity of galaxies in overdensities with M * ∼ 10 9.8 M ⊙ , 10 10.2 M ⊙, and 10 10.8 M ⊙ is higher relative to their field counterparts by 0.094 ± 0.051, 0.068 ± 0.028, and 0.052 ± 0.043 dex, respectively. However, this metallicity enhancement does not exist at higher redshift, z ∼ 2.3, where, compared to the field galaxies, we find 0.056 ± 0.043, 0.056 ± 0.028, and 0.096 ± 0.034 dex lower metallicity for galaxies in overdense environments with M * ∼ 10 9.8 M ⊙ , 10 10.2 M ⊙ and 10 10.7 M ⊙ , respectively. Our results suggest that, at 1.37 ≤ z ≤ 2.61, the variation of mass–metallicity relation with local environment is small ( 〈 0.1 dex), and reverses at z ∼ 2. Our results support the hypothesis that, at the early stages of cluster formation, owing to efficient gas cooling, galaxies residing in overdensities host a higher fraction of pristine gas with prominent primordial gas accretion, which lowers their gas-phase metallicity compared to their coeval field galaxies. However, as the universe evolves to lower redshifts ( z ≲ 2), the shock-heated gas in overdensities cannot cool down efficiently, and galaxies become metal-rich rapidly due to the suppression of pristine gas inflow and re-accretion of metal-enriched outflows in overdensities.
Type of Medium:
Online Resource
ISSN:
0004-637X
,
1538-4357
DOI:
10.3847/1538-4357/abd71f
Language:
Unknown
Publisher:
American Astronomical Society
Publication Date:
2021
detail.hit.zdb_id:
2207648-7
detail.hit.zdb_id:
1473835-1
SSG:
16,12
Bookmarklink