Faint submillimeter galaxies identified through their optical/near-infrared colors: 1. Spatial clustering and halo masses

Chen (???), Chian-Chou; Smail, Ian; Swinbank, A.M.; Simpson, James M.; Almaini, Omar; Conselice, Christopher J.; Hartley, Will G.; Mortlock, Alice; Simpson, Chris; Wilkinson, Aaron

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 spectral energy distribution 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-1 M 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 < z < 5 we find a tentative enhancement of the clustering of TCGs over the comparison star-forming galaxies, suggesting that some faint SMGs are physically associated pairs, perhaps reflecting a merging origin in their triggering.

Citation

Chen (陳建州), C., Smail, I., Swinbank, A., Simpson, J. M., Almaini, O., Conselice, C. J., …Wilkinson, A. (2016). Faint submillimeter galaxies identified through their optical/near-infrared colors: 1. Spatial clustering and halo masses. Astrophysical Journal, 831(1), 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: Jan 12, 2017
• Publicly Available Date: Jan 12, 2017
• Journal: Astrophysical Journal
• Print ISSN: 0004-637X
• Electronic ISSN: 1538-4357
• Publisher: American Astronomical Society
• Peer Reviewed: Peer Reviewed
• Volume: 831
• Issue: 1
• DOI: https://doi.org/10.3847/0004-637X/831/1/91
• Keywords: cosmology: observations ; galaxies: evolution ; galaxies: formation ; galaxies: high-redshift ; largescale; structure of universe ; submillimeter: galaxies
• Public URL: https://nottingham-repository.worktribe.com/output/819708
• Publisher URL: http://iopscience.iop.org/article/10.3847/0004-637X/831/1/91/meta