Details

Autor(en) / Beteiligte

• Xia An, Fang
• Simpson, J. M.
• Smail, Ian
• Swinbank, A. M.
• Ma, Cong
• Liu, Daizhong
• Lang, P.
• Schinnerer, E.
• Karim, A.
• Magnelli, B.
• Leslie, S.
• Bertoldi, F.
• Chen, Chian-Chou
• Geach, J. E.
• Matsuda, Y.
• Stach, S. M.
• Wardlow, J. L.
• Gullberg, B.
• Ivison, R. J.
• Ao, Y.
• Coogan, R. T.
• Thomson, A. P.
• Chapman, S. C.
• Wang, R.
• Wang, Wei-Hao
• Yang, Y.
• Asquith, R.
• Bourne, N.
• Coppin, K.
• Hine, N. K.
• Ho, L. C.
• Hwang, H. S.
• Kato, Y.
• Lacaille, K.
• Lewis, A. J. R.
• Oteo, I.
• Scholtz, J.
• Sawicki, M.
• Smith, D.

Titel

Multi-wavelength Properties of Radio- and Machine-learning-identified Counterparts to Submillimeter Sources in S2COSMOS

Ist Teil von

• The Astrophysical journal, 2019-11, Vol.886 (1), p.48

Ort / Verlag

Philadelphia: The American Astronomical Society

Erscheinungsjahr

2019

Quelle

EZB Free E-Journals

Beschreibungen/Notizen

• We identify multi-wavelength counterparts to 1147 submillimeter sources from the S2COSMOS SCUBA-2 survey of the COSMOS field by employing a recently developed radio+machine-learning method trained on a large sample of Atacama Large Millimeter/submillimeter Array (ALMA)-identified submillimeter galaxies (SMGs), including 260 SMGs identified in the AS2COSMOS pilot survey. In total, we identify 1222 optical/near-infrared (NIR)/radio counterparts to the 897 S2COSMOS submillimeter sources with S850 > 1.6 mJy, yielding an overall identification rate of (78 9)%. We find that (22 5)% of S2COSMOS sources have multiple identified counterparts. We estimate that roughly 27% of these multiple counterparts within the same SCUBA-2 error circles very likely arise from physically associated galaxies rather than line-of-sight projections by chance. The photometric redshift of our radio+machine-learning-identified SMGs ranges from z = 0.2 to 5.7 and peaks at z = 2.3 0.1. The AGN fraction of our sample is (19 4)%, which is consistent with that of ALMA SMGs in the literature. Comparing with radio/NIR-detected field galaxy population in the COSMOS field, our radio+machine-learning-identified counterparts of SMGs have the highest star formation rates and stellar masses. These characteristics suggest that our identified counterparts of S2COSMOS sources are a representative sample of SMGs at z 3. We employ our machine-learning technique to the whole COSMOS field and identified 6877 potential SMGs, most of which are expected to have submillimeter emission fainter than the confusion limit of our S2COSMOS surveys ( mJy). We study the clustering properties of SMGs based on this statistically large sample, finding that they reside in high-mass dark matter halos ((1.2 0.3) × 1013 h−1 ), which suggests that SMGs may be the progenitors of massive ellipticals we see in the local universe.