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 H? 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]/H? ratios and broad H? 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 ?m 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. © 2023. The Author(s). Published by the American Astronomical Society.