2025/06/30 by van der Wel, A., Martorano, M., Marchesini, D. +14
#Astrophysics of Galaxies (astro-ph.GA) #FOS: Physical sciences
paper · doi:10.48550/arxiv.2506.23669
JWST/NIRCam provides rest-frame near-IR photometry of galaxies up to z=2.5 with exquisite depth and accuracy. This affords an unprecedented view of the evolution of the UV-optical-near-IR color distribution and its interpretation in terms of the evolving dust attenuation, AV. We use the value-added data products (photometric redshift, stellar mass, rest-frame U-V and V-J colors, and A\rm V) provided by the public DAWN JWST Archive. This data product derives from fitting the spectral energy distributions obtained from multiple NIRCam imaging surveys, augmented with pre-existing HST imaging data. Our sample consists of a stellar mass complete sample of ≈ 28,000 M_⋆> 109~M_\odot galaxies in the redshift range 0.53× 1010~M_\odot), which have a pronounced tail of very red galaxies reaching V-J> 2.5 at z>1.5 that does not exist at z<1. Such red V-J can only be explained by dust attenuation, with typical values for M_⋆ ≈ 1011~M_\odot galaxies in the range AV≈ 1.5-3.5 at z≈ 2. This redshift evolution went largely unnoticed before because the photometric redshift estimates for the reddest (V-J>2.5), most attenuated galaxies has markedly improved thanks to the new, precise photometry. Despite the increased attenuation, U-V colors across the entire mass range are slightly bluer at higher z. In conclusion, whereas the rest-frame UV-optical color distribution evolves remarkably little from z=0.5 to z=2.5, the rest-frame optical-near-IR color distribution evolves strongly, primarily due to a very substantial increase with redshift in dust attenuation for massive galaxies. (Abbr.)