AzTEC∕ASTE 1.1 mm Deep Surveys: Number Counts and Clustering of Millimeter-bright Galaxies

Abstract

We present number counts and clustering properties of millimeter‐bright galaxies uncovered by the AzTEC camera mounted on the Atacama Submillimeter Telescope Experiment (ASTE). We surveyed the AKARI Deep Field South (ADF‐S), the Subaru/XMM Newton Deep Field (SXDF), and the SSA22 fields with an area of ∼0.25 deg2 each with an rms noise level of ∼0.4–1.0 mJy. We constructed differential and cumulative number counts, which provide currently the tightest constraints on the faint end. The integration of the best‐fit number counts in the ADF‐S find that the contribution of 1.1 mm sources with fluxes ≥1 mJy to the cosmic infrared background (CIB) at 1.1 mm is 12–16%, suggesting that the large fraction of the CIB originates from faint sources of which the number counts are not yet constrained. We estimate the cosmic star‐formation rate density contributed by 1.1 mm sources with ≥1 mJy using the best‐fit number counts in the ADF‐S and find that it is lower by about a factor of 5–10 compared to those derived from UV/optically‐selected galaxies at z∼2–3. The average mass of dark halos hosting bright 1.1 mm sources was calculated to be 1013–1014 M⊙. Comparison of correlation lengths of 1.1 mm sources with other populations and with a bias evolution model suggests that dark halos hosting bright 1.1 mm sources evolve into systems of clusters at present universe and the 1.1 mm sources residing the dark halos evolve into massive elliptical galaxies located in the center of clusters.