James Webb Space Telescope Feed Post

Arxiv: MSA-3D: Metallicity Gradients in Galaxies at z\sim1 with JWST/NIRSpec Slit-stepping Spectroscopy Published: 9/3/2024 8:35:12 AM Updated: 9/3/2024 8:35:12 AM

Paper abstract: The radial gradient of gas-phase metallicity is a powerful probe of thechemical and structural evolution of star-forming galaxies, closely tied todisk formation and gas kinematics in the early universe. We present spatiallyresolved chemical and dynamical properties for a sample of 26 galaxies at 0.5<~ z <~ 1.7 from the MSA-3D survey. These innovative observationsprovide 3D spectroscopy of galaxies at a spatial resolution approaching JWST'sdiffraction limit and a high spectral resolution of R~eq2700. Themetallicity gradients measured in our galaxy sample range from -0.05 to 0.02dex~kpc^{-1}. Most galaxies exhibit negative or flat radial gradients,indicating lower metallicity in the outskirts or uniform metallicity throughoutthe entire galaxy. We confirm a tight relationship between stellar mass andmetallicity gradient at z~1 with small intrinsic scatter of 0.02dex~kpc^{-1}. Our results indicate that metallicity gradients becomeincreasingly negative as stellar mass increases, likely because the moremassive galaxies tend to be more "disky". This relationship is consistent withthe predictions from cosmological hydrodynamic zoom-in simulations with strongstellar feedback. This work presents the effort to harness the multiplexingcapability of JWST NIRSpec/MSA in slit-stepping mode to map the chemical andkinematic profiles of high-redshift galaxies in large samples and at highspatial and spectral resolution.