Precise Identifications of Submillimeter Galaxies: Measuring the History of Massive Star-Forming Galaxies to z>5. (arXiv:1209.1626v1 [astro-ph.CO])

Precise Identifications of Submillimeter Galaxies: Measuring the History of Massive Star-Forming Galaxies to z>5. (arXiv:1209.1626v1 [astro-ph.CO]):
We carried out extremely sensitive Submillimeter Array (SMA) 340 GHz (860
micron) continuum imaging of a complete sample of SCUBA 850 micron sources (>4
sigma) with fluxes >3 mJy in the GOODS-N. Using these data and new SCUBA-2
data, we find that 4 of the 16 SCUBA sources are spurious. A further 3 resolve
into multiple fainter SMA galaxies, suggesting that our understanding of the
most luminous high-redshift dusty galaxies may not be as reliable as we
thought. Ten of the 16 independent SMA sources have spectroscopic redshifts
(optical/infrared or CO) to z=5.18. Using a new, ultradeep 20 cm image obtained
with the Karl G. Jansky Very Large Array (rms of 2.5 microJy), we find that all
16 of the SMA sources are detected at >5 sigma. Using Herschel far-infrared
(FIR) data, we show that the 5 isolated SMA sources with Herschel detections
are well described by an Arp 220 spectral energy distribution template in the
FIR. They also closely obey the local FIR-radio correlation, a result that does
not suffer from a radio bias. We compute the contribution from the 16 SMA
sources to the universal star formation rate per comoving volume. With
individual star formation rates in the range 700-5000 solar masses per year,
they contribute ~30% of the extinction-corrected ultraviolet selected star
formation rate density from z=1 to at least z=5. Star formation histories
determined from extinction-corrected ultraviolet populations and from
submillimeter galaxy populations only partially overlap, due to the extreme
ultraviolet faintness of some submillimeter galaxies.