Diversity and evolution of dust-attenuation curves from redshift z ∼ 1 to 9
Year: 2026
Type: article
Abstract: The UV–optical dust-attenuation curve is key to interpreting the intrinsic properties of galaxies and provides insights into the nature of dust grains and their geometry relative to stars. We constrained the UV-optical slope of the stellar attenuation curve using a spectroscopic-redshift sample of ∼3800 galaxies at z ∼ 1 − 9 to characterize the diversity and redshift evolution of stellar attenuation curves and to gain insight into dust production and evolution at high redshifts. The sample was constructed from three JWST/NIRCam grism surveys in GOODS-S, GOODS-N, and Abell-2744 fields, with a wealth of JWST/NIRCam and HST photometry. With constraints from spectroscopic redshifts and emission line fluxes, we use the Bayesian inference framework of Prospector SED fitting code with a flexible dust model to derive the attenuation curve for each galaxy. We find that the attenuation curve slope varies strongly with A V at all redshifts, becoming flatter at higher attenuation, attributed to the effect of scattering, dust-star geometry, and ISM chemical evolution. We find no strong correlation between attenuation curve slope and size or axis ratio, and the trends with stellar mass and star-formation rate are largely driven by their correlation with A V . We find strong evidence that at fixed A V , the curve becomes flatter with increasing redshift. On average, the attenuation curves derived here are shallower than those at z ∼ 0 and than the SMC curve. The highest redshift galaxies at z = 7 − 9 (124 galaxies – a significantly larger sample than in previous studies) show slopes even flatter than the Calzetti curve, implying reduced UV obscuration and lower IR luminosities than expected from an SMC dust curve, by as large as an order of magnitude. Hydrodynamical simulations that couple dust growth to gas chemical enrichment successfully reproduce the different loci of high- and low-redshift galaxies in the slope– A V diagram, suggesting that dust in high-redshift galaxies is increasingly dominated by large grains produced in supernova ejecta with limited ISM processing at early times.
Source: Astronomy and Astrophysics
Authors: Irene Shivaei, Rohan P. Naidu, Francisco Rodríguez Montero, Kosei Matsumoto, Joel Leja, Jorryt Matthee, Benjamin D. Johnson, Pascal A. Oesch, Jacopo Chevallard, Angela Adamo, Sarah Bodansky, Andrew J. Bunker, Alba Covelo Paz, Claudia Di Cesare, Eiichi Egami, Lukas J. Furtak, Kasper E. Heintz, Ivan Kramarenko, Romain A. Meyer, Naveen A. Reddy, Pierluigi Rinaldi, Sandro Tacchella, Alberto Torralba, Joris Witstok, Michael A. Wozniak, Mengyuan Xiao
Institutions: Centro de Astrobiología, Massachusetts Institute of Technology, University of Chicago, Ghent University, Pennsylvania State University, Institute of Science and Technology Austria, Center for Astrophysics Harvard & Smithsonian, University of Geneva, University of Copenhagen, University of Oxford, Stockholm University, University of Arizona, Ben-Gurion University of the Negev, University of California, Riverside, Space Telescope Science Institute, European Space Agency, University of Cambridge
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,865
Funders: National Science Foundation, National Aeronautics and Space Administration, Comunidad de Madrid, Space Telescope Science Institute, European Commission, National Research Foundation, Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung, Danmarks Grundforskningsfond, Fonds Wetenschappelijk Onderzoek, Vetenskapsrådet, Vlaamse regering, Staatssekretariat für Bildung, Forschung und Innovation, HORIZON EUROPE European Research Council
Awards: G103270039, G1338664626, A diagnosis of galaxy evolution with molecular gas, G256731684, Dissecting Dust in the Distant Universe: A Panchromatic Study with JWST and ALMA, G3816317015, Phasenübergänge und Instabilitäten, Cosmic Dawn Center (DAWN), G433322167, G4518818167, G4648019588, Modern man-machine communication methodologies., G5568641063, G58316358, G6273510985, G6662351857, G767601387, Star formation within evolving galaxies: the revolution of the James Webb Space Telescope, G8210229802
OpenAlex ID: W4416696430