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JWST/CEERS Sheds Light on Dusty Star-Forming Galaxies: Forming Bulges, Lopsidedness and Outside-In Quenching at Cosmic Noon Published: 7/14/2023 10:45:28 PM Updated: 7/14/2023 10:45:28 PM

Paper abstract: We investigate the morphology and physical properties of a sample of 22IR-selected dusty star-forming galaxies at Cosmic Noon (z ~ 2), using JamesWebb Space Telescope NIRCam images obtained in the EGS field for the CosmicEvolution Early Release Science survey. The exceptional resolution of theNIRCam images allows us to spatially resolve these galaxies up to 4.4um andidentify their bulge/core even when very extinguished by dust. Based onred-green-blue images using the F115W, F200W and F444W filters, we divide eachgalaxy in several uniformly colored regions, fit their respective SpectralEnergy Distribution and measure dust attenuations, stellar masses, starformation rates and ages. After classifying each region as star-forming orquiescent, we assign galaxies to three classes, depending on whether activestar-formation is located in the core, in the disk or in both. (i) ~70% of ourDSFGs have a compact highly dust attenuated star-forming core that can containup to 80% of the star-formation of the galaxy but only 20-30% of its stellarmass, and is always surrounded by a larger, less attenuated massive disk (noblue nuggets); (ii) 64% (27%) of disks are significantly (strongly) lopsided,likely due to asymmetric cold gas accretion, major mergers and/or large scaleinstabilities; (iii) 23% of galaxies have a star-forming core embedded in aquiescent disk, they are undergoing outside-in quenching, often facilitated bytheir strong lopsidedness inducing small and large scale instabilities; (iv)some galaxies host highly heterogeneous disks in term of RGB colors: these aredriven by in-homogeneous dust attenuation; and (v) we find surprising evidencefor clump-like substructures being quiescent and/or residing in quiescentregions. This work demonstrates the major impact JWST/NIRCam has onunderstanding the complexity of the evolution of distant massive galaxies.