ACP Seminar (Astronomy - Cosmology - Particle Physics)

Speaker: Nils Halverson (U Colorado)
Title: Cosmology with the South Pole Telescope
Date (JST): Wed, Dec 11, 2013, 14:00 - 15:00
Place: Seminar Room A
Abstract: The South Pole Telescope is a 10-m millimeter-wave telescope designed to conduct sensitive measurements of the Cosmic Microwave Background (CMB) with arcminute resolution. It has been operating from the South Pole since 2007. The first-generation receiver, SPT-SZ, mapped 2500 square degrees of sky at 90, 150 and 220 GHz from 2007 to 2011. Science from SPT-SZ includes cosmology from the discovery of hundreds of galaxy clusters detected with SPT via the Sunyaev-Zeldovich (SZ) effect, precision measurement of the CMB angular power spectrum damping tail, discovery of a new population of bright, lensed, high redshift dusty star-forming galaxies, and constraints on cosmological parameters such as the effective number of neutrino species. Since 2012, a second-generation polarization-sensitive receiver, SPTpol, has been taking deep measurements on small (100 and 500 square degrees) sky patches. So-called "B-mode" polarization anisotropy produced by gravitational lensing of the CMB by intervening matter was recently detected by SPTpol with 7.7-sigma significance. Future measurements of Cosmic Microwave Background (CMB) polarization have the potential to test the cosmological theory of inflation, probe physics at Grand Unified Theory (GUT) energy scales, constrain the sum of neutrino masses, and even provide precision tests of General Relativity. In this talk I will discuss recent results with SPT-SZ and SPTpol, instrument status, and plans a next generation CMB polarization receiver called SPT-3G, to be deployed in late 2015. Through a major upgrade to the SPT optics and a multi-chroic polarization-sensitive camera employing 15,234 detectors, SPT-3G will provide over an order of magnitude increase in mapping speed over the currently deployed SPTpol instrument.