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 - INSU - Institut national des sciences de l'Univers Accéder directement au contenu
Article Dans Une Revue The Astrophysical Journal Année : 2016

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

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

Résumé

We present an analysis of a deep (1σ = 13 μJy) 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 3.5σ significance at 1.2 mm. Our ALMA-selected sample has a median redshift of z=1.6+/- 0.4, 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 4.0× {10}10 {M} and ∼ 40 {M} 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 z∼ 1{--}2, 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.

Dates et versions

insu-03667690 , version 1 (13-05-2022)

Identifiants

Citer

M. Aravena, R. Decarli, F. Walter, E. da Cunha, F. E. Bauer, et al.. 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. The Astrophysical Journal, 2016, 833, ⟨10.3847/1538-4357/833/1/68⟩. ⟨insu-03667690⟩
4 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More