JWST's TEMPLATES for Star Formation: The First Resolved Gas-phase Metallicity Maps of Dust-obscured Star-forming Galaxies at z ∼ 4
Abstract
We present the first spatially resolved maps of gas-phase metallicity for two dust-obscured star-forming galaxies at z ~ 4, from the JWST TEMPLATES Early Release Science program, derived from NIRSpec integral field unit spectroscopy of the Hα and [N II] emission lines. Empirical optical line calibrations are used to determine that the sources are globally enriched to near-solar levels. While one source shows elevated [N II]/Hα ratios and broad Hα emission consistent with the presence of an active galactic nucleus in a ≳1 kpc region, we argue that both systems have already undergone significant metal enrichment as a result of their extremely high star formation rates. Utilizing Atacama Large Millimeter/submillimeter Array rest-frame 380 μm continuum and [CI](3P2-3P1) line maps we compare the spatial variation of the metallicity and gas-to-dust ratio in the two galaxies, finding the two properties to be anticorrelated on highly resolved spatial scales, consistent with various literature studies of z ~ 0 galaxies. The data are indicative of the enormous potential of JWST to probe the enrichment of the interstellar medium on ~kpc scales in extremely dust-obscured systems at z ~ 4 and beyond.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- November 2023
- DOI:
- 10.3847/1538-4357/acf712
- arXiv:
- arXiv:2307.10412
- Bibcode:
- 2023ApJ...958...64B
- Keywords:
-
- Galaxy evolution;
- High-redshift galaxies;
- Galaxy formation;
- Starburst galaxies;
- Strong gravitational lensing;
- 594;
- 734;
- 595;
- 1570;
- 1643;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- 14 pages, 6 figures, accepted for publication in ApJ