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Title: MSA-3D: Metallicity Gradients in Galaxies at z ∼ 1 with JWST/NIRSpec Slit-stepping Spectroscopy
Abstract The radial gradient of gas-phase metallicity is a powerful probe of the chemical and structural evolution of star-forming galaxies, closely tied to disk formation and gas kinematics in the early Universe. We present spatially resolved chemical and dynamical properties for a sample of 25 galaxies at 0.5 ≲ z ≲ 1.7 from theMSA-3Dsurvey. These innovative observations provide 3D spectroscopy of galaxies at a spatial resolution approaching JWST’s diffraction limit and a high spectral resolution ofR ≃ 2700. The metallicity gradients measured in our galaxy sample range from −0.03 to 0.02 dex kpc−1. Most galaxies exhibit negative or flat radial gradients, indicating lower metallicity in the outskirts or uniform metallicity throughout the entire galaxy. We confirm a tight relationship between stellar mass and metallicity gradient atz ∼ 1 with small intrinsic scatter of 0.02 dex kpc−1. Our results indicate that metallicity gradients become increasingly negative as stellar mass increases, likely because the more massive galaxies tend to be more “disky.” This relationship is consistent with the predictions from cosmological hydrodynamic zoom-in simulations with strong stellar feedback. This work presents the effort to harness the multiplexing capability of the JWST NIRSpec microshutter assembly in slit-stepping mode to map the chemical and kinematic profiles of high-redshift galaxies in large samples and at high spatial and spectral resolution.  more » « less
Award ID(s):
2307327 2108230
PAR ID:
10625004
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
ApJL
Date Published:
Journal Name:
The Astrophysical Journal Letters
Volume:
978
Issue:
2
ISSN:
2041-8205
Page Range / eLocation ID:
L39
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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