Early JWST imaging reveals strong optical and NIR color gradients in galaxies at $z\sim 2$ driven mostly by dust

Abstract

Recent studies have shown that galaxies at cosmic noon are redder in the center and bluer in the outskirts, mirroring results in the local universe. These color gradients could be caused by either gradients in the stellar age or dust opacity; however, distinguishing between these two causes is impossible with rest-frame optical photometry alone. Here we investigate the underlying causes of the gradients from spatially-resolved rest-frame $U-V$ vs. $V-J$ color-color diagrams, measured from early observations with the James Webb Space Telescope. We use $1\mu m-4\mu m$ NIRCam photometry from the CEERS survey of a sample of 54 galaxies with $M_{\ast }/M_{\odot }>10$ at redshifts $1.7<z<2.3$ selected from the 3D-HST catalog. We model the light profiles in the F115W, F200W and F356W NIRCam bands using \texttt{imcascade}, a Bayesian implementation of the Multi-Gaussian expansion (MGE) technique which flexibly represents galaxy profiles using a series of Gaussians. We construct resolved rest-frame $U-V$ and $V-J$ color profiles. The majority of star-forming galaxies have negative gradients (i.e. redder in the center, bluer in the outskirts) in both $U-V$ and $V-J$ colors consistent with radially decreasing dust attenuation. A smaller population (roughly 15\%) of star-forming galaxies have positive $U-V$ but negative $V-J$ gradients implying centrally concentrated star-formation. For quiescent galaxies we find a diversity of UVJ color profiles, with roughly one-third showing star-formation in their center. This study showcases the potential of JWST to study the resolved stellar populations of galaxies at cosmic noon.

Updated to match published version, new Figure 5 and some text changes

References in corpus (16)

• EAZY: A Fast, Public Photometric Redshift Code
• 3D-HST WFC3-selected Photometric Catalogs in the Five CANDELS/3D-HST Fields: Photometry, Photometric Redshifts and Stellar Masses
• Detection of quiescent galaxies in a bicolor sequence from z=0-2
• What do we learn from IRAC observations of galaxies at 2 < z < 3.5?
• A Long Time Ago in a Galaxy Far, Far Away: A Candidate z ~ 12 Galaxy in Early JWST CEERS Imaging
• Half-mass radii for ~7,000 galaxies at 1.0 < z < 2.5: most of the evolution in the mass-size relation is due to color gradients
• Beyond UVJ: More Efficient Selection of Quiescent Galaxies With UV / Mid-IR Fluxes
• Structural evolution in massive galaxies at z~2
• UVI colour gradients of 0.4<z<1.4 star-forming main sequence galaxies in CANDELS: dust extinction and star formation profiles
• Galaxy Sizes Since $z=2$ from the Perspective of Stellar Mass Distribution within Galaxies
• The Impact of Dust on the Sizes of Galaxies in the Epoch of Reionization
• Quenching and the UVJ diagram in the SIMBA cosmological simulation
• The Origins of UV-optical Color Gradients in Star-forming Galaxies at z ~ 2: Predominant Dust Gradients But Negligible sSFR Gradients
• Recent Star-formation in a Massive Slowly-Quenched Lensed Quiescent Galaxy at z=1.88
• Reproducing the UVJ Color Distribution of Star-forming Galaxies at 0.5 < z < 2.5 with a Geometric Model of Dust Attenuation
• Bayesian fitting of multi-Gaussian expansion models to galaxy images

Cited by in corpus (20)

• CEERS Key Paper V: A triality on the nature of HST-dark galaxies
• JWST reveals a population of ultra-red, flattened disk galaxies at 2<z<6 previously missed by HST
• JWST/CEERS sheds light on dusty star-forming galaxies: forming bulges, lopsidedness and outside-in quenching at cosmic noon
• The Size-Mass relation at Rest-Frame $1.5\mu$m from JWST/NIRCam in the COSMOS-WEB and PRIMER-COSMOS fields
• Rest-Frame Near-Infrared Radial Light Profiles up to z=3 from JWST/NIRCam: Wavelength Dependence of the Sérsic Index
• JWST's PEARLS: resolved study of the stellar and dust components in starburst galaxies at cosmic noon
• More is better: Strong constraints on the stellar properties of LEGA-C z ~ 1 galaxies with Prospector
• Solution to the conflict between the resolved and unresolved galaxy stellar mass estimation from the perspective of JWST
• JADES: Rest-frame UV-to-NIR Size Evolution of Massive Quiescent Galaxies from Redshift z=5 to z=0.5
• Ages and metallicities of quiescent galaxies: confronting broadband ($UVJ$) colours with stellar absorption lines
• Age and metal gradients in massive quiescent galaxies at $0.6\lesssim z\lesssim 1.0$: implications for quenching and assembly histories
• Evolution of the Sérsic Index up to z=2.5 from JWST and HST
• Exploring the Gas-Phase Metallicity Gradients of Star-forming Galaxies at Cosmic Noon
• The mass-dependent UVJ diagram at cosmic noon: A challenge for galaxy evolution models and dust radiative transfer
• PRIMER: JWST/MIRI reveals the evolution of star-forming structures in galaxies at z<2.5
• JWST Reveals Bulge-dominated Star-forming Galaxies at Cosmic Noon
• The ALMA-CRISTAL Survey: Complex kinematics of the galaxies at the end of the Reionization Era
• Transforming galaxies with EASE: widespread structural changes enabled by short-lived spirals
• Everything Every Band All at Once I: A Global Morphology Catalog in Abell 2744 based on UNCOVER/MegaScience
• SE3D: Building a radiative transfer emulator to fit panchromatic resolved galaxy observations with 3D models of dust and stars