Program: GS-2009B-Q-16

Title:Spectroscopic Confirmation and Dynamical Mass Estimates of South Pole Telescope SZE Selected Galaxy Clusters
PI:Joseph Mohr
Co-I(s): Adam Stanford, Anthony Gonzalez, Ryan Foley, Alfredo Zenteno, Jeeseon Song, Christopher Stubbs, Armin Rest, Will High, John Carlstrom, Tom Crawford

Abstract

We propose to carry out GMOS spectroscopy in eleven Sunyaev-Zel'dovich Effect (SZE) selected clusters from the South Pole Telescope (SPT) survey. These systems are the high z part (0.5<z<1) of a complete sample of 16 clusters extracted from 200 deg^2 of sky with masses above M~5x10^{14}Mo. The SPT cluster survey is designed to deliver large and uniformly selected cluster samples to enable a study of the cosmic acceleration. Achieving this scientific goal requires understanding SPT cluster selection and developing a precise understanding of the relationship between the amplitude of the cluster SZE signature and the cluster mass. Our Gemini program is designed to address both these needs. With the proposed spectroscopy we will confirm the existence of dynamically bound collections of galaxies, providing a crucial test of the SPT cluster selection. We will observe two masks in each system, providing enough member redshifts to measure the cluster velocity dispersion and to measure the redshifts of giant arcs where they are present. This information, together with X-ray data from scheduled Chandra and XMM observations of these clusters and a proposed deep lensing study will provide crucial constraints on the masses of these SZE selected systems.

Publications using this program's data