2025A&A...693A.190J

Context. Understanding the dust content of galaxies, its evolution with redshift and its relation to stars and star formation is fundamental for our understanding of galaxy evolution. Dust acts as a catalyst of star formation and as a shield for star light. Advanced millimeter facilities like ALMA have made dust observation ever more accessible, even at high redshift. However, dust emission is typically very faint, making the use of stacking techniques is instrumental in the study of dust in statistically sound samples.
Aims. Using the ALMA Lensing Cluster Survey (ALCS) wide-area band-6 continuum dataset (∼ 110 arcmin² across 33 lensing clusters), we constrain the dust-mass evolution with redshift, stellar mass, and star formation rate (SFR).
Methods. After binning sources according to redshift, SFR, and stellar mass as extracted from an HST-IRAC catalog, we performed a set of continuum-stacking analyses in the image domain using LINESTACKER on sources between z = 1 and z = 5, which further improved the depth of our data. The large field of view provided by the ALCS allowed us to reach a final sample of ∼4000 galaxies with known coordinates and SED-derived physical parameters. We stacked sources with an SFR between 10^–3 and 10³ M_⊙ per year and a stellar mass between 10⁸ and 10¹² M_⊙, and we split them into different stellar mass and SFR bins. Through stacking, we retrieved the continuum 1.2 mm flux, which is a known dust-mass tracer. This allowed us to derive the dust-mass evolution with redshift and its relation to the SFR and stellar mass.
Results. We clearly detect the continuum in most of the subsamples. From the nondetections, we derive 3σ upper limits. We observe a steady decline in the average dust mass with redshift. Moreover, sources with a higher stellar mass or SFR have a higher dust mass on average. This allows us to derive scaling relations. Our results mostly agree well with models at z ∼ 1-3, but they indicate a typically lower dust mass than predicted at higher redshift.