Dust Temperature of Compact Star-forming Galaxies at z ∼ 1–3 in 3D-HST/CANDELS

Abstract

Abstract Recent simulation studies suggest that the compaction of star-forming galaxies (SFGs) at high redshift might be a critical process, during which the central bulge is being rapidly built, followed by quenching of the star formation. To explore dust properties of SFGs with compact morphology, we investigate the dependence of dust temperature, T dust, on their size and star formation activity, using a sample of massive SFGs with at 1 < z < 3, drawn from the 3D-HST/CANDELS database in combination with deep Herschel observations. T dust is derived via fitting the mid-to-far-infrared photometry with a mid-infrared power law and a far-infrared modified blackbody. We find that both extended and compact SFGs generally follow a similar T dust − z evolutionary track as that of the main-sequence galaxies. The compact SFGs seem to share similar dust temperature with extended SFGs. Despite the frequent occurrence of active galactic nuclei (AGNs) in compact SFGs, we do not observe any effect on dust caused by the presence of AGNs in these galaxies during the compaction. Our results disfavor different ISM properties between compact and extended SFGs, suggesting that a rapid and violent compaction process might be not necessary for the formation of compact SFGs.