Millimeter imaging of submillimeter galaxies in the COSMOS field: redshift distribution

Scientific paper - Original scientific paper

• Author: Vernesa Smolčić
• Author: M. Aravena
• Author: F. Navarrete
• Author: E. Schinnerer
• Author: D. A. Riechers
• Author: F. Bertoldi
• Author: C. Feruglio
• Author: A. Finoguenov
• Author: M. Salvato
• Author: M. Sargent
• Author: H. J. McCracken
• Author: M. Albrecht
• Author: A. Karim
• Author: P. Capak
• Author: C. L. Carilli
• Author: N. Cappelluti
• Author: M. Elvis
• Author: O. Ilbert
• Author: J. Kartaltepe
• Author: S. Lilly
• Author: D. Sanders
• Author: K. Sheth
• Author: N. Z. Scoville
• Author: Y. Taniguchi
• Author's institution: University of Zagreb; Faculty of Science; (Department of Physics)
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Physics

Abstract (english)

We present new IRAM Plateau de Bure interferometer (PdBI) 1.3 mm continuum observations at ~1.5" resolution of 28 submillimeter galaxies (SMGs), previously discovered with the 870 μm bolometer LABOCA at the APEX telescope from the central 0.7 deg^2 of the COSMOS field. Nineteen out of the 28 LABOCA sources were detected with PdBI at a ≳3σ level of ≈1.4 mJy/beam. A combined analysis of this new sample with existing interferometrically identified SMGs in the COSMOS field yields the following results: i) ≳15%, and possibly up to ~40% of single-dish detected SMGs consist of multiple sources; ii) statistical analysis of multi-wavelength counterparts to single-dish SMGs shows that only ~50% have real radio or IR counterparts; iii) ~18% of interferometric SMGs have either no multi-wavelength counterpart or only a radio-counterpart; and iv) ~50–70% of z ≳ 3 SMGs have no radio counterparts (down to an rms of 7–12 μJy at 1.4 GHz). Using the exactinterferometric positions to identify the multi-wavelength counterparts allows us to determine accurate photometric redshifts for these sources. The redshift distributions of the combined and the individual 1.1 mm and 870 μm selected samples shows a higher mean and a broader width than those derived in previous studies. This study finds that on average brighter and/or mm- selected SMGs are located at higher redshifts, consistent with previous studies. The mean redshift for the 1.1 mm selected sample (z = 3.1 ± 0.4) is tentatively higher than that for the 870 μm selected sample ( = 2.6 ± 0.4). Based on our nearly complete sample of AzTEC 1.1 mm SMGs in a 0.15 deg^2 area, we infer a higher surface density of z ≳ 4 SMGs than predicted by current cosmological models. In summary, our findings imply that interferometric identifications at (sub-)millimeter wavelengths are crucial to build statistically complete and unbiased samples of SMGs.

• Keywords (english): surveys, galaxies: starburst, galaxies: fundamental parameters, galaxies: high-redshift, galaxies: statistics, submillimeter: galaxies
• Language: english
• Publication type: Scientific paper - Original scientific paper
• Publication status: Published
• Peer review: Peer review - international
• Publication version: Published version
• Journal title: Astronomy and Astrophysics
• Numbering: vol. 548, A4
• p-ISSN: 0004-6361
• DOI: https://doi.org/10.1051/0004-6361/201219368
• URN:NBN: urn:nbn:hr:217:035951
• Publication: 2012
• Document URL: https://www.aanda.org/articles/aa/abs/2012/12/aa19368-12/aa19368-12.html
• Type of resource: Text
• Access conditions: Open access
• Public note: © 2012 ESO. Received 8 April 2012. Accepted 24 May 2012. Published online 13 November 2012. Based on observations carried out with the IRAM Plateau de Bure Interferometer. IRAM is supported by INSU/CNRS (France), MPG (Germany) and IGN (Spain).
• Created on: 2019-11-15 19:19:12