AN ALMA SURVEY OF SUBMILLIMETER GALAXIES IN THE EXTENDED CHANDRA DEEP FIELD SOUTH: THE REDSHIFT DISTRIBUTION AND EVOLUTION OF SUBMILLIMETER GALAXIES
Journal article, 2014
We present the first photometric redshift distribution for a large sample of 870 mu m submillimeter galaxies (SMGs) with robust identifications based on observations with ALMA. In our analysis we consider 96 SMGs in the Extended Chandra Deep Field South, 77 of which have 4-19 band photometry. We model the SEDs for these 77 SMGs, deriving a median photometric redshift of z(phot) = 2.3 +/- 0.1. The remaining 19 SMGs have insufficient photometry to derive photometric redshifts, but a stacking analysis of Herschel observations confirms they are not spurious. Assuming that these SMGs have an absolute H-band magnitude distribution comparable to that of a complete sample of z similar to 1-2 SMGs, we demonstrate that they lie at slightly higher redshifts, raising the median redshift for SMGs to zphot = 2.5 +/- 0.2. Critically we show that the proportion of galaxies undergoing an SMG-like phase at z >= 3 is at most 35% +/- 5% of the total population. We derive a median stellar mass of M star = (8 +/- 1) x 10(10) M circle dot, although there are systematic uncertainties of up to 5 x for individual sources. Assuming that the star formation activity in SMGs has a timescale of similar to 100 Myr, we show that their descendants at z similar to 0 would have a space density and MH distribution that are in good agreement with those of local ellipticals. In addition, the inferred mass-weighted ages of the local ellipticals broadly agree with the look-back times of the SMG events. Taken together, these results are consistent with a simple model that identifies SMGs as events that form most of the stars seen in the majority of luminous elliptical galaxies at the present day.
DEGREE EXTRAGALACTIC SURVEY
YALE-CHILE MUSYC
galaxies: starburst
1.4 GHZ SURVEY
galaxies: evolution
OLD STELLAR POPULATIONS
STAR-FORMING GALAXIES
PHOTOMETRIC REDSHIFT
BLACK-HOLES
galaxies: high-redshift
X-RAY SOURCES
SIMILAR-TO 2
FAR-INFRARED PROPERTIES
Author
J. M. Simpson
Durham University
A. M. Swinbank
Durham University
I. Smail
Durham University
D. M. Alexander
Durham University
W. N. Brandt
Pennsylvania State University
F. Bertoldi
University of Bonn
C. De Breuck
European Southern Observatory (ESO)
S. C. Chapman
Dalhousie University
K. E. K. Coppin
University of Hertfordshire
E. da Cunha
Max Planck Society
A. L. R. Danielson
Durham University
H. Dannerbauer
University of Vienna
T. R. Greve
University College London (UCL)
J. A. Hodge
Max Planck Society
R. J. Ivison
University of Edinburgh
A. Karim
University of Bonn
Kirsten Kraiberg Knudsen
Chalmers, Earth and Space Sciences, Radio Astronomy and Astrophysics
B. M. Poggianti
Istituto nazionale di astrofisica (INAF)
E. Schinnerer
Max Planck Society
A. P. Thomson
Durham University
F. Walter
Max Planck Society
J. L. Wardlow
Niels Bohr Institute
University of California at Irvine (UCI)
A. Weiss
Max Planck Society
P.P. van der Werf
Leiden University
Astrophysical Journal
0004-637X (ISSN) 1538-4357 (eISSN)
Vol. 788 2 125Subject Categories
Astronomy, Astrophysics and Cosmology
Roots
Basic sciences
DOI
10.1088/0004-637x/788/2/125