Alma redshifts of millimeter-selected galaxies from the SPT survey: The redshift distribution of dusty star-forming galaxies

Abstract

Using the Atacama Large Millimeter/submillimeter Array, we have conducted a blind redshift survey in the 3 mm atmospheric transmission window for 26 strongly lensed dusty star-forming galaxies (DSFGs) selected with the South Pole Telescope. The sources were selected to have S1.4 mm > 20 mJy and a dust-like spectrum and, to remove low-z sources, not have bright radio (S843 MHz < 6 mJy) or far-infrared counterparts (S 100 μm < 1 Jy, S60 μm < 200 mJy). We robustly detect 44 line features in our survey, which we identify as redshifted emission lines of 12CO, 13CO, C I, H2O, and H2O +. We find one or more spectral features in 23 sources yielding a ∼90% detection rate for this survey; in 12 of the..