Confirming the evolution of the dust mass function in galaxies over the past 5 billion years

Abstract

The amount of evolution in the dust content of galaxies over the past 5 billion years of cosmic history is contested in the literature. Here, we present a far-infrared (FIR) census of dust based on a sample of 29 241 galaxies with redshifts ranging from 0 < z < 0.5 using data from the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS). We use the spectral energy distribution fitting tool MAGPHYS and a stacking analysisto investigate the evolution of dust mass and temperature of FIR-selected galaxies as a function of both luminosity and redshift. At low redshifts, we find that the mass-weighted and luminosity-weighted dust temperatures from the stacking analysis both exhibit a trend for brighter galaxies to have warmer dust. In higher redshift bins, we see some evolution in both mass-weighted and luminosity-weighted dust temperatures with redshift, but the effect is strongest for luminosity-weighted temperature. The measure of dust content in galaxies at z < 0.1 (the dust mass function) has a different shape to that derived using optically selected galaxies from the same region of sky. We revise the local dust mass density (z < 0.1) to ρd= (1.37 ± 0.08) × 105 M Mpc−3 h−170 ; corresponding to an overall fraction of baryons (by mass) stored in dust of fmb(dust) = (2.22 ± 0.13) × 10−5. We confirm evolution in both the luminosity density and dust mass density over the past few billion years (ρd ∝ (1 + z)2.6±0.6), with a flatter evolution than observed in previous FIR-selected studies. We attribute the evolution in ρL and ρm to an evolution in the dust mass.