Dust removal timescale in galaxies across cosmic time

¹ DARK, Niels Bohr Institute, University of Copenhagen, Jagtvej 155A, DK-2200 Copenhagen, Denmark
² Astronomical Observatory Institute, Faculty of Physics and Astronomy, Adam Mickiewicz University, ul. Słoneczna 36, 60-286 Poznań, Poland

^⋆ Corresponding author: aleksandra.lesniewska@nbi.ku.dk

Received: 2 April 2025
Accepted: 24 June 2025

Abstract

Understanding the evolution of dust in galaxies is crucial because it affects the dynamics and cooling of gas, star formation, and chemical evolution. Recent work on dust removal in galaxies indicates timescales of gigayears, with old stellar populations and active galactic nuclei the primary drivers of this process. However, most statistically significant studies have focused on low redshifts, z<0.4. Here we determine the dust removal timescale in galaxies over a wide range of redshifts, up to z∼5. We used publicly available catalogue data of infrared-selected galaxies observed by Herschel. Using the inferred dust masses, stellar masses, and stellar ages, we calculated the dust removal timescale in a sample of more than 120 000 galaxies. We find that, with increasing redshift, the dust removal timescale decreases from 1.8 Gyr at redshift z∼0.05 to less than 450 Myr at z>3. Galaxies at higher redshifts undergo more efficient dust removal than galaxies at lower redshifts, likely driven by active galactic nucleus activity, supernova shocks, and astration. These findings indicate that dust removal evolves over cosmic time, reflecting the changing mechanisms regulating the dust content of galaxies as the Universe evolves.