| Title: |
JADES: the chemical enrichment pattern of distant galaxies – α enhancement, silicon depletion, and iron enhancement |
| Authors: |
Isobe, Y; Maiolino, R; Ji, X; D’Eugenio, F; Simmonds, C; Scholtz, J; Juodžbalis, I; Saxena, A; Witstok, J; Kobayashi, C; Vanni, I; Salvadori, S; Watanabe, K; Monty, S; Belokurov, V; Feltre, A; McClymont, W; Tacchella, S; Curti, M; Übler, H; Charlot, S; Bunker, AJ; Chevallard, J; Curtis-Lake, E; Kumari, N |
| Publisher Information: |
Oxford University Press |
| Publication Year: |
2026 |
| Collection: |
Oxford University Research Archive (ORA) |
| Description: |
We present gas-phase abundances of carbon (C), -elements (O, Ne, Si, and Ar), and iron (Fe) obtained from stacked spectra of high-z star-forming galaxies with the deep Near Infrared Spectrograph medium-resolution data from the James Webb Space Telescope Advanced Deep Extragalactic Survey. Our 564 sources at –7 have a median stellar mass of and a median star-formation rate of , placing them close to the star-formation main sequence. We find that the stacked spectrum of all our 564 sources has relatively low , moderate , and low values at a low gas-phase metallicity of (), suggesting dominant yields of core-collapse supernovae evolved from massive stars. The detection of a weak [Si iii] emission line in our stacked spectrum provides a silicon-to-oxygen abundance ratio of , which is lower than that of stars in the Milky Way disc and lower than expected by chemical evolution models, suggesting silicon depletion on to dust grains. Likewise, this Si/O value is lower than that we newly derive for two individual galaxies (GN-z11 and RXCJ2248) with negligible dust attenuation. By performing spectral stacking in bins of , star-formation rate (SFR), specific SFR (sSFR), and ultraviolet continuum slope , we identify [Fe iii] line detections in the high-sSFR bin and the blue- bin, both of which exhibit supersolar Fe/O ratios, while their C/O, Ar/O, and Si/O ratios are comparable to those of the all-sources stack. Our findings support a chemically young gas composition with rapid dust depletion in the general population of high-z star-forming galaxies, while raising the possibility of anomalous, selective Fe/O enhancement at the very early epoch of star formation. |
| Document Type: |
article in journal/newspaper |
| Language: |
English |
| Relation: |
https://doi.org/10.1093/mnras/stag123 |
| DOI: |
10.1093/mnras/stag123 |
| Availability: |
https://doi.org/10.1093/mnras/stag123; https://ora.ox.ac.uk/objects/uuid:0679b6f7-2c88-40b1-be3d-2c1da74a51c2 |
| Rights: |
info:eu-repo/semantics/openAccess ; CC Attribution (CC BY) |
| Accession Number: |
edsbas.6232BA4F |
| Database: |
BASE |