The South Pole Telescope (SPT) is a large (10m diameter) millimeter-wave telescope at the South Pole. A large-format millimeter-wave "camera" is currently being used to detect new clusters of galaxies via the Sunyaev-Zeldovich (SZ) effect. The SZ effect is a great tool for finding new clusters because the signal is nearly independent of distance to the cluster, so we can detect them all the way back to the beginnings of cluster formation.
Once we have a catalog of many (hopefully 1000's) of clusters and have worked with collaborators using optical telescopes to measure redshifts, we expect to use these clusters as probes of the expansion history of the universe, a(t). By charting a(t), we can learn more about the properties of the Dark Energy that is currently accelerating the expansion.
Observing started in early 2007, and will continue for at least a few years. We are also funded to build a polarization-sensitive receiver for the SPT, which we will use to measure the lensing of CMB photon paths by structure along the line of sight (and thereby understand much better the distribution of Dark Matter in the universe) as well as search for the effects of primordial gravity waves that may have been created during the Inflationary epoch, when the universe was only 10^-34 seconds old.So far there is only one publication from the SPT, which describes the telescope and receiver before they were actually built:
- "The South Pole Telescope", J. Ruhl etal, astro-ph/0411122 SPIE Millimeter and Submillimeter Detectors for Astronomy II, Eds J. Zmuidzinaas, W. S. Holland, and S. Withington, Vol 5498, p11-29, (2004).
The SPT collaboration includes groups at U. Chicago, UC Berkeley, LBNL, Cardiff, U. Illinois, McGill, and U. Colorado. The main SPT website is maintained at U. Chicago, at http://spt.uchicago.edu/.