"A new population of millimeter galaxies discovered by the South Pole Telescope"

Joaquin Vieira, Caltech

The South Pole Telescope (SPT) has surveyed hundreds of square degrees to milli-Jansky levels at 1.4 mm and 2.0 mm. 
Based on the ratio of flux in these two bands, we are able to separate the detected sources into two populations, one consistent with
synchrotron emission from active galactic nuclei (AGN) and one consistent with thermal emission from dust. All of the most significantly
detected members of the synchrotron-dominated population are associated with sources in previously published radio catalogs. 
Some of the dust-dominated sources are associated with nearby (z<<1) galaxies whose dust emission is also detected by the Infrared
Astronomy Satellite (IRAS).  However, most of the bright, dust-dominated sources have no counterparts in any existing catalog.
We argue that these sources represent the rarest, brightest, and possibly strongly-lensed members of the population commonly referred
to as sub-millimeter galaxies (SMGs). Because these sources are selected at longer wavelengths than in typical SMG surveys, they are
expected to have a higher mean redshift distribution  than objects currently in the literature, and may provide a new window on galaxy
formation in the early universe. I will present the status of our followup observations of these remarkable sources and discuss them
within the context of present and upcoming sub-mm observatories. I will give a general overview of the SPT project and recent results,
including the recently released SZ cluster catalog and the CMB powerspectrum.