Faint Submillimeter Galaxies Identified through Their Optical/Near-infrared Colors. I. Spatial Clustering and Halo Masses

Chen, C.-C.; Smail, I.; Swinbank, A.M.; Simpson, J.M.; Almaini, O.; Conselice, C.J.; Hartley, W.G.; Mortlock, A.; Simpson, C.; Wilkinson, A.

Abstract

The properties of submillimeter galaxies (SMGs) that are fainter than the confusion limit of blank-field single-dish surveys (S850≲ 2 mJy) are poorly constrained. Using a newly developed color selection technique, Optical-Infrared Triple Color (OIRTC), that has been shown to successfully {select} such faint SMGs, we identify a sample of 2938 OIRTC-selected galaxies, dubbed Triple Color Galaxies (TCGs), in the UKIDSS-UDS field. We show that these galaxies have a median 850 μm flux of S850=0.96±0.04 mJy (equivalent to a star-formation rate SFR ∼60−100 M⊙ yr−1 based on SED fitting), representing the first large sample of faint SMGs that bridges the gap between bright SMGs and normal star-forming galaxies in S850 and LIR. We assess the basic properties of TCGs and their relationship with other galaxy populations at z∼2. We measure the two-point autocorrelation function for this population and derive a typical halo mass of log10(Mhalo) =12.9+0.2−0.3, 12.7+0.1−0.2, and 12.9+0.2−0.3 h−1M⊙ at z=1−2, 2−3, and 3−5, respectively. Together with the bright SMGs (S850≳2 mJy) and a comparison sample of less far-infrared luminous star-forming galaxies, we find a lack of dependence between spatial clustering and S850 (or SFR), suggesting that the difference between these populations may lie in their local galactic environment. Lastly, on the scale of ∼8−17 kpc at 1

Citation

Chen, C., Smail, I., Swinbank, A., Simpson, J., Almaini, O., Conselice, C., …Wilkinson, A. (2016). Faint Submillimeter Galaxies Identified through Their Optical/Near-infrared Colors. I. Spatial Clustering and Halo Masses. Astrophysical Journal, 831(1), Article 91. https://doi.org/10.3847/0004-637x/831/1/91

• Journal Article Type: Article
• Acceptance Date: Aug 13, 2016
• Online Publication Date: Oct 28, 2016
• Publication Date: Nov 1, 2016
• Deposit Date: Feb 22, 2017
• Publicly Available Date: Mar 9, 2017
• Journal: Astrophysical Journal
• Print ISSN: 0004-637X
• Electronic ISSN: 1538-4357
• Publisher: American Astronomical Society
• Peer Reviewed: Peer Reviewed
• Volume: 831
• Issue: 1
• Article Number: 91
• DOI: https://doi.org/10.3847/0004-637x/831/1/91
• Public URL: https://durham-repository.worktribe.com/output/1362795
• Related Public URLs: https://arxiv.org/abs/1609.00388