Details

Autor(en) / Beteiligte

• Aravena, M.
• Decarli, R.
• Walter, F.
• Cunha, E. Da
• Bauer, F. E.
• Carilli, C. L.
• Daddi, E.
• Elbaz, D.
• Ivison, R. J.
• Riechers, D. A.
• Smail, I.
• Swinbank, A. M.
• Weiss, A.
• Anguita, T.
• Assef, R. J.
• Bell, E.
• Bertoldi, F.
• Bacon, R.
• Bouwens, R.
• Cortes, P.
• Cox, P.
• Gónzalez-López, J.
• Hodge, J.
• Ibar, E.
• Inami, H.
• Infante, L.
• Karim, A.
• Fèvre, O. Le Le
• Magnelli, B.
• Ota, K.
• Popping, G.
• Sheth, K.
• van der Werf, P.
• Wagg, J.

Titel

THE ALMA SPECTROSCOPIC SURVEY IN THE HUBBLE ULTRA DEEP FIELD: CONTINUUM NUMBER COUNTS, RESOLVED 1.2 mm EXTRAGALACTIC BACKGROUND, AND PROPERTIES OF THE FAINTEST DUSTY STAR-FORMING GALAXIES

Ist Teil von

• The Astrophysical journal, 2016-12, Vol.833 (1), p.68

Ort / Verlag

Philadelphia: The American Astronomical Society

Erscheinungsjahr

2016

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• ABSTRACT We present an analysis of a deep (1 = 13 Jy) cosmological 1.2 mm continuum map based on ASPECS, the ALMA Spectroscopic Survey in the Hubble Ultra Deep Field. In the 1 arcmin2 covered by ASPECS we detect nine sources at significance at 1.2 mm. Our ALMA-selected sample has a median redshift of , with only one galaxy detected at z > 2 within the survey area. This value is significantly lower than that found in millimeter samples selected at a higher flux density cutoff and similar frequencies. Most galaxies have specific star formation rates (SFRs) similar to that of main-sequence galaxies at the same epoch, and we find median values of stellar mass and SFRs of and yr−1, respectively. Using the dust emission as a tracer for the interstellar medium (ISM) mass, we derive depletion times that are typically longer than 300 Myr, and we find molecular gas fractions ranging from ∼0.1 to 1.0. As noted by previous studies, these values are lower than those using CO-based ISM estimates by a factor of ∼2. The 1 mm number counts (corrected for fidelity and completeness) are in agreement with previous studies that were typically restricted to brighter sources. With our individual detections only, we recover 55% 4% of the extragalactic background light (EBL) at 1.2 mm measured by the Planck satellite, and we recover 80% 7% of this EBL if we include the bright end of the number counts and additional detections from stacking. The stacked contribution is dominated by galaxies at , with stellar masses of (1-3) × 1010 M . For the first time, we are able to characterize the population of galaxies that dominate the EBL at 1.2 mm.